WorldWideScience

Sample records for controlled field experiment

  1. User experiences with editorial control in online newspaper comment fields

    DEFF Research Database (Denmark)

    Løvlie, Anders Sundnes; Ihlebæk, Karoline Andrea; Larsson, Anders Olof

    2017-01-01

    This article investigates user experiences with editorial control in online newspaper comment fields following the public backlash against online comments after the 2011 terror attacks in Norway. We analyze data from a survey of online news consumers focusing on experiences and attitudes towards...... editorial control set against a spectrum between “interventionist” and “noninterventionist” positions. Results indicate that interventionist respondents rate the quality of online comments as poor, whereas noninterventionist respondents have most often experienced being the target of editorial control...... measures and feel that editorial control has intensified after the terror attacks. We conclude that newspapers should pay attention to the different needs of participants when devising strategies for editorial control. Media professionals should also consider changes to increase the transparency...

  2. Microrelief-Controlled Overland Flow Generation: Laboratory and Field Experiments

    Directory of Open Access Journals (Sweden)

    Xuefeng Chu

    2015-01-01

    Full Text Available Surface microrelief affects overland flow generation and the related hydrologic processes. However, such influences vary depending on other factors such as rainfall characteristics, soil properties, and initial soil moisture conditions. Thus, in-depth research is needed to better understand and evaluate the combined effects of these factors on overland flow dynamics. The objective of this experimental study was to examine how surface microrelief, in conjunction with the factors of rainfall, soil, and initial moisture conditions, impacts overland flow generation and runoff processes in both laboratory and field settings. A series of overland flow experiments were conducted for rough and smooth surfaces that represented distinct microtopographic characteristics and the experimental data were analyzed and compared. Across different soil types and initial moisture conditions, both laboratory and field experiments demonstrated that a rough soil surface experienced a delayed initiation of runoff and featured a stepwise threshold flow pattern due to the microrelief-controlled puddle filling-spilling-merging dynamics. It was found from the field experiments that a smooth plot surface was more responsive to rainfall variations especially during an initial rainfall event. However, enhanced capability of overland flow generation and faster puddle connectivity of a rough field plot occurred during the subsequent rain events.

  3. NMR magnetic field controller for pulsed nuclear magnetic resonance experiments

    International Nuclear Information System (INIS)

    Scheler, G.; Anacker, M.

    1975-01-01

    A nuclear magnetic resonance controller for magnetic fields, which can also be used for pulsed NMR investigations, is described. A longtime stability of 10 -7 is achieved. The control signal is generated by a modified time sharing circuit with resonance at the first side band of the 2 H signal. An exact calibration of the magnetic field is achieved by the variation of the H 1 - or of the time-sharing frequency. (author)

  4. Jet Grouting. Control of execution and result parameters. Test fields - Experience in Chile

    International Nuclear Information System (INIS)

    Ayarza, P. M.; Vukotic, G.

    2014-01-01

    This article emphasizes the importance of Test Fields in project that includes the Jet Grouting technique. In particular, the Chilean experience is analyzed, where the Jet Grouting was first introduced by Pilots Terratest S. A. in the year 2010, only, only in 2011 the first project using jet columns was constructed. The versatilely of this technique allows its use in a wide variety of projects, for example, soil capacity improvement, settlement control, reduction of soil permeability and other environmental applications. Currently, the most common applications are underpinning existing foundations, ground improvement, lateral support of excavations, hydraulic barriers, slope stabilization, liquefaction control, among others. The Jet Grouting is one of the most demanding soil improvement technique and requires excellence in designing and execution engineers and other involved specialist. It is therefore essential to ensure exhaustive control to the execution and final parameters, in order to check that the product- Jet Grouting element-have the design properties, and implement modifications if necessary. Many authors strongly advises that if there is no comparable experience and even if there is, a Test Field of Jet Grouting elements has to be executed in site. This field consists in a nearby area with similar geotechnical conditions of the project, where Jet Grouting test columns will be constructed. This Test Field will allow selecting the most effective execution parameters and verifying that the final product has he correct design properties. (Author)

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  7. Insights into organic carbon oxidation potential during fluvial transport from controlled laboratory and natural field experiments

    Science.gov (United States)

    Scheingross, Joel S.; Dellinger, Mathieu; Golombek, Nina; Hilton, Robert G.; Hovius, Niels; Sachse, Dirk; Turowski, Jens M.; Vieth-Hillebrand, Andrea; Wittmann, Hella

    2017-04-01

    Over geologic timescales, the exchange of organic carbon (OC) between the atmosphere, biosphere and geosphere is thought to be a major control on atmospheric carbon dioxide (CO2) concentrations, and hence global climate. The carbon fluxes from the oxidation of rock-derived OC (a CO2 source) and erosion and transport of biospheric OC (a potential CO2 sink) during fluvial transit are approximately the same order of magnitude or larger than those from silicate weathering (France-Lanord and Derry, 1997; Bouchez et al., 2010). Despite field data showing oxidation of OC moving downstream in lowland rivers, it is unclear if losses occur primarily during active fluvial transport within the river, where OC is in continual motion within an aerated environment, or during longer periods when OC is temporarily stored in river floodplains which may be anoxic. This represents a major knowledge gap, as the unknown location of OC oxidation (i.e., river vs. floodplain) limits our ability to develop process-based models that can be employed to predict OC losses, constrain carbon budgets, and unravel links between climate, tectonics, and erosion. To fill this gap, we investigated the potential for OC oxidation in both controlled laboratory experiments and a simplified field setting. We consider both rock-derived and biospheric OC. Our experiments simulated fluvial transport without floodplain storage, allowing mixtures of OC-rich and siliciclastic sediment to be transported for distances of 1000 km in annular flumes while making time-series measurements of OC concentration in both the solid (POC) and dissolved (DOC) loads, as well as measurements of rhenium concentration, which serves as a proxy for the oxidation of rock-derived OC. These transport experiments were compared to static, control experiments where water and sediment in the same proportion were placed in still water. Initial results for transport of OC-rich soil show similar behavior between the transport and static

  8. Paper 58714 - Exploring activated faults hydromechanical processes from semi-controled field injection experiments

    Science.gov (United States)

    Guglielmi, Y.; Cappa, F.; Nussbaum, C.

    2015-12-01

    The appreciation of the sensitivity of fractures and fault zones to fluid-induced-deformations in the subsurface is a key question in predicting the reservoir/caprock system integrity around fluid manipulations with applications to reservoir leakage and induced seismicity. It is also a question of interest in understanding earthquakes source, and recently the hydraulic behavior of clay faults under a potential reactivation around nuclear underground depository sites. Fault and fractures dynamics studies face two key problems (1) the up-scaling of laboratory determined properties and constitutive laws to the reservoir scale which is not straightforward when considering faults and fractures heterogeneities, (2) the difficulties to control both the induced seismicity and the stimulated zone geometry when a fault is reactivated. Using instruments dedicated to measuring coupled pore pressures and deformations downhole, we conducted field academic experiments to characterize fractures and fault zones hydromechanical properties as a function of their multi-scale architecture, and to monitor their dynamic behavior during the earthquake nucleation process. We show experiments on reservoir or cover rocks analogues in underground research laboratories where experimental conditions can be optimized. Key result of these experiments is to highlight how important the aseismic fault activation is compared to the induced seismicity. We show that about 80% of the fault kinematic moment is aseismic and discuss the complex associated fault friction coefficient variations. We identify that the slip stability and the slip velocity are mainly controlled by the rate of the permeability/porosity increase, and discuss the conditions for slip nucleation leading to seismic instability.

  9. Controlling stray electric fields on an atom chip for experiments on Rydberg atoms

    Science.gov (United States)

    Davtyan, D.; Machluf, S.; Soudijn, M. L.; Naber, J. B.; van Druten, N. J.; van Linden van den Heuvell, H. B.; Spreeuw, R. J. C.

    2018-02-01

    Experiments handling Rydberg atoms near surfaces must necessarily deal with the high sensitivity of Rydberg atoms to (stray) electric fields that typically emanate from adsorbates on the surface. We demonstrate a method to modify and reduce the stray electric field by changing the adsorbate distribution. We use one of the Rydberg excitation lasers to locally affect the adsorbed dipole distribution. By adjusting the averaged exposure time we change the strength (with the minimal value less than 0.2 V /cm at 78 μ m from the chip) and even the sign of the perpendicular field component. This technique is a useful tool for experiments handling Rydberg atoms near surfaces, including atom chips.

  10. Visual perception and appraisal of persons with impairments: a randomised controlled field experiment using photo elicitation.

    Science.gov (United States)

    Reinhardt, Jan Dietrich; Ballert, Carolina Saskia; Fellinghauer, Bernd; Lötscher, Alexander; Gradinger, Felix; Hilfiker, Roger; Graf, Sibylle; Stucki, Gerold

    2011-01-01

    Visual cues from persons with impairments may trigger stereotypical generalisations that lead to prejudice and discrimination. The main objective of this pilot study is to examine whether visual stimuli of impairment activate latent prejudice against disability and whether this connection can be counteracted with priming strategies. In a field experiment, participants were asked to rate photographs showing models with mental impairments, wheelchair users with paraplegia, and persons without any visible impairment. Participants should appraise the models with regard to several features (e.g. communicativeness, intelligence). One hundred participants rated 12 photo models yielding a total of 1183 observations. One group of participants was primed with a cover story introducing visual perception of impairment as the study's gist, while controls received neutral information. Photo models with mental impairments were rated lowest and models without visible impairment highest. In participants who did not have prior contacts with persons with impairments, priming led to a levelling of scores of models with and without impairment. Prior contacts with persons with impairments created similar effects as the priming. Unexpectedly, a pattern of converse double discrimination to the disadvantage of men with mental impairments was revealed. Signs of stereotypical processing of visual cues of impairment have been found in participants of the Swiss general population. Personal contact with persons with impairments as well as priming participants seems to reduce stereotyping.

  11. Effects of a PID Control System on Electromagnetic Fields in an nEDM Experiment

    Science.gov (United States)

    Molina, Daniel

    2017-09-01

    The Kellogg Radiation Laboratory is currently testing a prototype for an experiment that hopes to identify the electric dipole moment of the neutron. As part of this testing, we have developed a PID (proportional, integral, derivative) feedback system that uses large coils to fix the value of local external magnetic fields, up to linear gradients. PID algorithms compare the current value to a set-point and use the integral and derivative of the field with respect to the set-point to maintain constant fields. We have also developed a method for zeroing linear gradients within the experimental apparatus. In order to determine the performance of the PID algorithm, measurements of both the internal and external fields were obtained with and without the algorithm running, and these results were compared for noise and time stability. We have seen that the PID algorithm can reduce the effect of disturbance to the field by a factor of 10.

  12. A field experiment on the controls of sediment transport on bedrock erosion

    Science.gov (United States)

    Beer, A. R.; Turowski, J. M.; Fritschi, B.; Rieke-Zapp, D.; Campana, L.; Lavé, J.

    2012-12-01

    The earth`s surface is naturally shaped by interactions of physical and chemical processes. In mountainous regions with steep topography river incision fundamentally controls the geomorphic evolution of the whole landscape. There, erosion of exposed bedrock sections by fluvial sediment transport is an important mechanism forming mountain river channels. The links between bedload transport and bedrock erosion has been firmly established using laboratory experiments. However, there are only few field datasets linking discharge, sediment transport, impact energy and erosion that can be used for process understanding and model evaluation. To fill this gap, a new measuring setup has been commissioned to raise an appropriate simultaneous dataset of hydraulics, sediment transport and bedrock erosion at high temporal and spatial resolution. Two natural stone slabs were installed flush with the streambed of the Erlenbach, a gauged stream in the Swiss Pre-Alps. They are mounted upon force sensors recording vertical pressure und downstream shear caused by passing sediment particles. The sediment transport rates can be assessed using geophone plates and an automated moving basket system taking short-term sediment samples. These devices are located directly downstream of the stone slabs. Bedrock erosion rates are measured continuously with erosion sensors at sub-millimeter accuracy at three points on each slab. In addition, the whole slab topography is surveyed with photogrammetry and a structured-light 3D scanner after individual flood events. Since the installation in 2011, slab bedrock erosion has been observed during several transport events. We discuss the relation between hydraulics, bedload transport, resulting pressure forces on the stone slabs and erosion rates. The aim of the study is the derivation of an empirical process law for fluvial bedrock erosion driven by moving sediment particles.

  13. Coordinated voltage control for multiple wind plants in Eastern Wyoming. Analysis, field experience and validation

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Nicholas; MacDowell, Jason; Chmiel, Gary; Konopinski, Ryan; Gautam, Durga [GE Energy, Schenectady, NY (United States); Laughter, Grant; Hagen, Dave [PacifiCorp., Salt Lake City, UT (United States)

    2012-07-01

    At high levels of wind power penetration, multiple wind plants may be the predominant generation resource over large geographic areas. Thus, not only do wind plants need to provide a high level of functionality, they must coordinate properly with each other. This paper describes the analysis and field testing of wind plant voltage controllers designed to improve system voltage performance through passive coordination. The described wind power plant controls can coordinate the real and reactive power response of multiple wind turbines and thereby make the plant function as a single ''grid friendly'' power generation source. For this application, involving seven large wind plants with predominantly GE wind turbines in Eastern Wyoming, the voltage portion of the controllers were configured and tuned to allow the collective reactive power response of multiple wind plants in the region to work well together. This paper presents the results of the initial configuration and tuning study, and the results of the subsequent field tuning and testing of the modified controls. The paper also presents some comparisons of the measured field performance with the stability simulation models, which show that the available wind plant models provide accurate, high fidelity results for actual operating conditions of commercial wind power plants. (orig.)

  14. Field controlled experiments of mercury accumulation in crops from air and soil

    Energy Technology Data Exchange (ETDEWEB)

    Niu Zhenchuan [Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085 (China); Zhang Xiaoshan, E-mail: zhangxsh@rcees.ac.cn [Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085 (China); Wang Zhangwei, E-mail: wangzhw@rcees.ac.cn [Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085 (China); Ci Zhijia [Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085 (China)

    2011-10-15

    Field open top chambers (OTCs) and soil mercury (Hg) enriched experiments were employed to study the influence of Hg concentrations in air and soil on the Hg accumulation in the organs of maize (Zea mays L.) and wheat (Triticum aestivum L.). Results showed that Hg concentrations in foliages were correlated significantly (p < 0.05) with air Hg concentrations but insignificantly correlated with soil Hg concentrations, indicating that Hg in crop foliages was mainly from air. Hg concentrations in roots were generally correlated with soil Hg concentrations (p < 0.05) but insignificantly correlated with air Hg concentrations, indicating that Hg in crop roots was mainly from soil. No significant correlations were found between Hg concentrations in stems and those in air and soil. However, Hg concentrations in upper stems were usually higher than those in bottom stems, implying air Hg might have stronger influence than soil Hg on stem Hg accumulation. - Highlights: > Hg accumulation in crop organs was studied by OTCs and soil Hg enriched experiments. > Hg accumulation in foliages and roots was mainly from air and soil, respectively. > Air Hg had stronger influence than soil Hg on stem Hg accumulation. > Foliar Hg concentrations showed the trend of increase over growth stages. - Capsule Mercury accumulated in the aboveground organs of crop was mainly from the air.

  15. Field controlled experiments of mercury accumulation in crops from air and soil

    International Nuclear Information System (INIS)

    Niu Zhenchuan; Zhang Xiaoshan; Wang Zhangwei; Ci Zhijia

    2011-01-01

    Field open top chambers (OTCs) and soil mercury (Hg) enriched experiments were employed to study the influence of Hg concentrations in air and soil on the Hg accumulation in the organs of maize (Zea mays L.) and wheat (Triticum aestivum L.). Results showed that Hg concentrations in foliages were correlated significantly (p < 0.05) with air Hg concentrations but insignificantly correlated with soil Hg concentrations, indicating that Hg in crop foliages was mainly from air. Hg concentrations in roots were generally correlated with soil Hg concentrations (p < 0.05) but insignificantly correlated with air Hg concentrations, indicating that Hg in crop roots was mainly from soil. No significant correlations were found between Hg concentrations in stems and those in air and soil. However, Hg concentrations in upper stems were usually higher than those in bottom stems, implying air Hg might have stronger influence than soil Hg on stem Hg accumulation. - Highlights: → Hg accumulation in crop organs was studied by OTCs and soil Hg enriched experiments. → Hg accumulation in foliages and roots was mainly from air and soil, respectively. → Air Hg had stronger influence than soil Hg on stem Hg accumulation. → Foliar Hg concentrations showed the trend of increase over growth stages. - Capsule Mercury accumulated in the aboveground organs of crop was mainly from the air.

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

    Science.gov (United States)

    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.

  17. Impact of thermostatically controlled loads' demand response activation on aggregated power: A field experiment

    DEFF Research Database (Denmark)

    Lakshmanan, Venkatachalam; Marinelli, Mattia; Kosek, Anna Magdalena

    2015-01-01

    activation. The outcome of this experimental study quantifies the actual flexibility of household TCLs and the consequence for the different parties with respect to power behaviour. Each DR activation method adopts different scenarios to meet the power reduction, and has different impacts on the parameters......This paper describes the impacts of different types of DR (demand response) activation on TCLs' (thermostatically controlled loads) aggregated power. The different parties: power system operators, DR service providers (or aggregators) and consumers, have different objectives in relation to DR....... The experiments are conducted with real domestic refrigerators representing TCL. Activating refrigerators for DR with a delay reduces the ISE (integral square error) in power limitation by 28.46%, overshoot by 7.69%. The delay in refrigerator activation causes reduction in power ramp down rate by 39.90%, ramp up...

  18. 4D ERT Monitoring of Subsurface Water Pipe Leakage During a Controlled Field Experiment

    Science.gov (United States)

    Inauen, C.; Chambers, J. E.; Wilkinson, P. B.; Meldrum, P.; Swift, R. T.; Uhlemann, S.; Gunn, D.; Dashwood, B.; Taxil, J.; Curioni, G.

    2016-12-01

    Locating and delineating leakage from subsurface pipelines is an important task for civil engineers. 4D Electrical Resistivity Tomography (ERT) allows changes in subsurface resistivity to be imaged at a high spatial and temporal resolution in a minimally invasive manner. It is therefore a promising tool to supplement conventional point-sensing techniques to monitor subsurface flow processes. To assess the efficacy of ERT for pipe leakage monitoring several controlled leak experiments were carried out at a test site in Blagdon, Bristol, UK. To simulate the leak, a plastic pipe with a hole was buried below a flat, grassed area at a depth of 0.7 m, representing a standard UK mains water pipe installation. The water table at the site lies well below the surface meaning that the experiment took entirely place in the vadose zone, where changes in resistivity are primarily sensitive to water content variations. The ERT array covered an area of 6.5m x 6.5m around the leak location. Data acquisition was carried out with the BGS PRIME (Proactive Infrastructure Monitoring and Evaluation) system, which facilitates remote scheduling and autonomous ERT data collection and transmission. To obtain the resistivity changes of the subsurface a 4D inversion was carried out using a Gauss-Newton approach with spatial and temporal smoothness constraints. We were able to reliably observe the onset, spread and cessation of the leakage. Measurements from in-situ soil sensors at several depths above and below the leak complemented the ERT data and allowed us to assess their reliability and directly relate them to hydrogeological processes. Moreover, through experimental tests with soil samples from the test area, a Waxman-Smits relation was obtained to directly convert the changes in electrical resistivity to gravimetric soil moisture content. With future experiments on the test site more work is planned towards survey optimization, automated processing and tracking of leakage plumes.

  19. Field services experiences

    International Nuclear Information System (INIS)

    Colflesh, J.A.; Kruse, P.W.; Merluzzi, R.A.

    1985-01-01

    Combustion Engineering (C-E) is a large diversified manufacturer of products and services for the energy field. At this time, C-E has supplied the nuclear steam supply systems for eleven operating nuclear power plants with two additional units currently undergoing start-up testing. The focus of C-E's commitment in the nuclear power plant services area is the Nuclear Services organization within the Nuclear Power Systems Division. The Nuclear Services organization provides services on a timely cost efficient basis; and dedicates resources to developing new products and services which are truly responsive to the needs of operating power plants world wide. In the paper, C-E's capabilities and experience in the field of nuclear services are described. Highlighted are our capabilities in the areas of transition management services, operating services and engineering services

  20. Wake field acceleration experiments

    International Nuclear Information System (INIS)

    Simpson, J.D.

    1988-01-01

    Where and how will wake field acceleration devices find use for other than, possibly, accelerators for high energy physics? I don't know that this can be responsibly answered at this time. What I can do is describe some recent results from an ongoing experimental program at Argonne which support the idea that wake field techniques and devices are potentially important for future accelerators. Perhaps this will spawn expanded interest and even new ideas for the use of this new technology. The Argonne program, and in particular the Advanced Accelerator Test Facility (AATF), has been reported in several fairly recent papers and reports. But because this is a substantially new audience for the subject, I will include a brief review of the program and the facility before describing experiments. 10 refs., 7 figs

  1. Radiation field control at the latest BWR plants -- design principle, operational experience and future subjects

    Energy Technology Data Exchange (ETDEWEB)

    Uchida, Shunsuke [Energy Research Lab., Ibaraki (Japan); Ohsumi, Katsumi; Takashima, Yoshie [Hitachi Works, Ibaraki (Japan)

    1995-03-01

    Improvements of operational procedures to control water chemistry, e.g., nickel/iron control, as well as application of hardware improvements for reducing radioactive corrosion products resulted in an extremely low occupational exposure of less than 0.5 man.Sv/yr without any serious impact on the radwaste system, for BWR plants involved in the Japanese Improvement and Standardization Program. Recently, {sup 60}C radioactively in the reactor water has been increasing due to less crud fixation on the two smooth surfaces of new type high performance fuels and to the pH drop caused by chromium oxide anions released from stainless steel structures and pipings. This increase must be limited by changes in water chemistry, e.g., applications of modified nickel/iron ratio control and weak alkali control. Controlled water chemistry to optimize three points, the plant radiation level and integrities of fuel and structural materials, is the primary future subject for BWR water chemistry.

  2. [Performance of Grass Swales for Controlling Pollution of Roadway Runoff in Field Experiments].

    Science.gov (United States)

    Huang, Jun-jie; Shen, Qing-ran; Li, Tian

    2015-06-01

    Two different styles of grass swales were built in new Binhu region of Hefei city to monitor the flux and quality of the influent and effluent water under actual precipitation conditions, in order to evaluate the performance of water quality purification and pollution load control for roadway runoff. The results showed that both of the grass swales could effectively remove the pollutants such as TSS, COD, Pb, Cu, Cd, Zn in roadway runoff; the median EMC removal efficiencies of TSS and COD were 67.1%, 46.7% respectively,for facility I, and the median EMC removal efficiencies of TSS and COD were 78.6%, 58.6% respectively, for facility II; the concentrations of Pb, Cu, Zn in the effluent of facility II could meet the requirements of the surface water quality class V; release of nitrogen and phosphorus occurred in both facilities I and I[ in several rainfall events, mainly in heavy storms; the removal efficiencies of TP in the two grass swales were improved with the increase of influent concentration; the mean removal efficiencies of TP in facilities I and II were 14.7% and 45.4%, respectively; the load control performance of facility II for pollutants such as TSS, COD, TP, TN, NH4+ -N and NO3- -N was better than that of facility I; in the district with poor soil permeability and low ground slope, application of dry swale could achieve better performance in water quality control and pollution load reduction of roadway runoff.

  3. Nuclide-migration field experiments

    International Nuclear Information System (INIS)

    Erdal, B.R.; Wolfsberg, K.; Johnstone, J.K.; Erickson, K.L.; Friedman, A.M.; Fried, S.; Hines, J.J.

    1981-03-01

    When considering groundwater flow and radionuclide retention in the complex flow systems that can occur in geologic formations, one has a serious problem in determining if laboratory studies are being performed under conditions appropriate to natural systems. This document is the project plan for a program designed to begin to address these problems. The project is being carried out jointly by the Los Alamos National Laboratory, Sandia National Laboratories, and Argonne National Laboratory. The work has three principal objectives: (1) to develop the experimental, instrumental, and safety techniques necessary to conduct controlled, small-scale radionuclide migration field experiments, including those involving actinides; (2) to use these techniques to define radionuclide migration through rock by performing generic, at-depth experiments under closely monitored conditions; and (3) to determine whether available lithologic, geochemical, and hydrologic properties together with existing or developing transport models are sufficient and appropriate to describe real field conditions

  4. Nuclide-migration field experiments

    Energy Technology Data Exchange (ETDEWEB)

    Erdal, B.R.; Wolfsberg, K.; Johnstone, J.K.; Erickson, K.L.; Friedman, A.M.; Fried, S.; Hines, J.J.

    1981-03-01

    When considering groundwater flow and radionuclide retention in the complex flow systems that can occur in geologic formations, one has a serious problem in determining if laboratory studies are being performed under conditions appropriate to natural systems. This document is the project plan for a program designed to begin to address these problems. The project is being carried out jointly by the Los Alamos National Laboratory, Sandia National Laboratories, and Argonne National Laboratory. The work has three principal objectives: (1) to develop the experimental, instrumental, and safety techniques necessary to conduct controlled, small-scale radionuclide migration field experiments, including those involving actinides; (2) to use these techniques to define radionuclide migration through rock by performing generic, at-depth experiments under closely monitored conditions; and (3) to determine whether available lithologic, geochemical, and hydrologic properties together with existing or developing transport models are sufficient and appropriate to describe real field conditions.

  5. Field reversal experiments (FRX)

    International Nuclear Information System (INIS)

    Linford, R.K.; Armstrong, W.T.; Platts, D.A.; Sherwood, E.G.

    1978-01-01

    The equilibrium, confinement, and stability properties of the reversed-field configuration (RFC) are being studied in two theta-pinch facilities. The RFC is an elongated toroidal plasma confined in a purely poloidal field geometry. The open field lines of the linear theta pinch support the closed-field RFC much like the vertical field centers the toroidal plasma in a tokamak. Depending on stability and confinement properties, the RFC might be used to greatly reduce the axial losses in linear fusion devices such as mirrors, theta pinches, and liners. The FRX systems produce RFC's with a major radius R = 2-6 cm, minor radius a approximately 2 cm, and a total length l approximately 35 cm. The observed temperatures are T/sub e/ approximately 100 eV and T/sub i/ = 150-350 eV with a peak density n approximately 2 x 10 15 cm -3 . After the plasma reaches equilibrium, the RFC remains stable for up to 30 μs followed by the rapid growth of the rotational m = 2 instability, which terminates the confinement. During the stable equilibrium, the particle and energy confinement times are more than 10 times longer than in an open-field system. The behavior of the m = 2 mode qualitatively agrees with the theoretically predicted instability for rotational velocities exceeding some critical value

  6. Field reversal experiments (FRX)

    International Nuclear Information System (INIS)

    Linford, R.K.; Armstrong, W.T.; Platts, D.A.; Sherwood, E.G.

    1979-01-01

    The equilibrium, confinement, and stability properties of the reversed-field configuration (RFC) are being studied in two theta-pinch facilities. The RFC is an elongated toroidal plasma confined in a purely poloidal field geometry. The open field lines of the linear theta pinch support the closed-field RFC much like the vertical field centres the toroidal plasma in a tokamak. Depending on stability and confinement properties, the RFC might be used to greatly reduce the axial losses in linear fusion devices such as mirrors, theta pinches, and liners. The FRX systems produce RFCs with a major radius R=2-6cm, a minor radius a approximately 2cm, and a total length l approximately 35cm. The observed temperatures are Tsub(e) approximately 100eV and Tsub(i)=150-350eV with a peak density n approximately 2x10 15 cm -3 . After the plasma has reached equilibrium, the RFC remains stable for up to 30μs, followed by the rapid growth of the rotational m=2 instability, which terminates the confinement. During the stable equilibrium, the particle and energy confinement times are more than 10 times longer than in an open-field system. The behaviour of the m=2 mode agrees qualitatively with the theoretically predicted instability for rotational velocities exceeding some critical value. (author)

  7. Reversed field pinch experiments

    International Nuclear Information System (INIS)

    Roberston, S.

    1991-05-01

    The Reversatron RFP is usually operated with toroidal field windings which are a continuous helix of 144 turns. These windings produce a poloidal current which is uniform around the torus. The distribution of current is fixed by the geometry so that the applied field has only an m = 0, n = 0 component. The windings cannot act to stabilize an m = 0 mode with |n| > 0 or any m = 1 mode because these modes will excite no current in the windings. It has recently been suggested that parallel connected field coils might act as a shell by forcing the flux within each winding to be the same. Coils connected in parallel must have the same voltage at their terminals and thus must enclose the same volt-seconds or flux. Data from ZT-40 show that the discharges are more quiescent when parallel or series-parallel connected windings are used

  8. Undergraduate reactor control experiment

    International Nuclear Information System (INIS)

    Edwards, R.M.; Power, M.A.; Bryan, M.

    1992-01-01

    A sequence of reactor and related experiments has been a central element of a senior-level laboratory course at Pennsylvania State University (Penn State) for more than 20 yr. A new experiment has been developed where the students program and operate a computer controller that manipulates the speed of a secondary control rod to regulate TRIGA reactor power. Elementary feedback control theory is introduced to explain the experiment, which emphasizes the nonlinear aspect of reactor control where power level changes are equivalent to a change in control loop gain. Digital control of nuclear reactors has become more visible at Penn State with the replacement of the original analog-based TRIGA reactor control console with a modern computer-based digital control console. Several TRIGA reactor dynamics experiments, which comprise half of the three-credit laboratory course, lead to the control experiment finale: (a) digital simulation, (b) control rod calibration, (c) reactor pulsing, (d) reactivity oscillator, and (e) reactor noise

  9. Controlling magnetic field profiles

    International Nuclear Information System (INIS)

    Freeman, J.R.

    1979-04-01

    A method for designing solenoid magnets with controlled field profiles is discussed. The method, originated by D.B. Montgomery, minimizes both the field errors and the power consumption. An NOS time-sharing computer program for the CDC-6600, entitled MAGCOR, was constructed to provide an interactive magnet design capability. Results obtained during the design of magnets for a radial line electron accelerator are presented. 9 figures

  10. Selective psychological effects of nudging, gamification and rational information in converting commuters from cars to buses: A controlled field experiment

    DEFF Research Database (Denmark)

    Lieberoth, Andreas; Jensen, Niels Holm; Bredahl, Thomas Viskum Gjelstrup

    2018-01-01

    Persuasive strategies like nudging, gamification, and goal-oriented health feedback are now used across a variety of behavior domains including transportation, exercise and sustainable consumption. However, documentation is lacking for their precise effects on entrenched behavioral habits...... such as day-to-day commuting, or how well such persuasive strategies fare compared to each other in terms of behaviour change rates. In this study of bus commuting, we pitted nudging, gamification, and goal-oriented health information against each other in a field quasi-experiment. The experiment lasted one...

  11. Faulting of rocks in three-dimensional strain fields I. Failure of rocks in polyaxial, servo-control experiments

    Science.gov (United States)

    Reches, Ze'ev; Dieterich, James H.

    1983-05-01

    The dependence of the number of sets of faults and their orientation on the intermediate strain axis is investigated through polyaxial tests, reported here, and theoretical analysis, reported in an accompanying paper. In the experiments, cubic samples of Berea sandstone, Sierra-White and Westerly granites, and Candoro and Solnhofen limestones were loaded on their three pairs of faces by three independent, mutually perpendicular presses at room temperature. Two of the presses were servo-controlled and applied constant displacement rates throughout the experiment. Most samples display three or four sets of faults in orthorhombic symmetry. These faults form in several yielding events that follow a stage of elastic deformation. In many experiments, the maximum and the intermediate compressive stresses interchange orientations during the yielding events, where the corresponding strains are constant. The final stage of most experiments is characterized by slip along the faults.

  12. Faulting of rocks in three-dimensional strain fields I. Failure of rocks in polyaxial, servo-control experiments

    Science.gov (United States)

    Reches, Z.; Dieterich, J.H.

    1983-01-01

    The dependence of the number of sets of faults and their orientation on the intermediate strain axis is investigated through polyaxial tests, reported here, and theoretical analysis, reported in an accompanying paper. In the experiments, cubic samples of Berea sandstone, Sierra-White and Westerly granites, and Candoro and Solnhofen limestones were loaded on their three pairs of faces by three independent, mutually perpendicular presses at room temperature. Two of the presses were servo-controlled and applied constant displacement rates throughout the experiment. Most samples display three or four sets of faults in orthorhombic symmetry. These faults form in several yielding events that follow a stage of elastic deformation. In many experiments, the maximum and the intermediate compressive stresses interchange orientations during the yielding events, where the corresponding strains are constant. The final stage of most experiments is characterized by slip along the faults. ?? 1983.

  13. The effects of financial education on financial literacy and savings behavior : Evidence from a controlled field experiment in Dutch primary schools

    NARCIS (Netherlands)

    Kalwij, A.S.; Alessie, Rob; Dinkova, M.; Schonewille, Gea; van der Schors, Anna; van der Werf, Minou

    In this paper, we report the results of a controlled field experiment designed to estimate the short-term effects of a 45-minute financial education program on financial literacy and savings behavior in Dutch primary schools. Among fifth and sixth graders, the program led to a pre- to posttest

  14. Using E-Portfolios in a Field Experience Placement: Examining Student-Teachers' Attitudes towards Learning in Relationship to Personal Value, Control and Responsibility

    Science.gov (United States)

    Shroff, Ronnie H.; Trent, John; Ng, Eugenia M. W.

    2013-01-01

    This study extends the ownership of learning model by using e-portfolios in a field experience placement to examine student-teachers' attitudes towards learning in relationship to personal value, feeling in control and taking responsibility. A research model is presented based on research into ownership of learning. The student e-portfolio…

  15. A Field Experiment in Motivating Employee Ideas

    OpenAIRE

    Susanne Neckermann; Michael Gibbs; Christoph Siemroth

    2014-01-01

    markdownabstract__Abstract__ We study the effects of a field experiment designed to motivate employee ideas, at a large technology company. Employees were encouraged to submit ideas on process and product improvements via an online system. In the experiment, the company randomized 19 account teams into treatment and control groups. Employees in treatment teams received rewards if their ideas were approved. Nothing changed for employees in control teams. Our main finding is that rewards substa...

  16. Field experiments in salt formations

    International Nuclear Information System (INIS)

    Kuehn, K.

    1986-01-01

    Field experiments in salt formations started as early as 1965 with Project Salt Vault in the Lyons Mine, Kansas, U.S.A., and with the purchase of the Asse salt mine by the German Federal Government. Underground tests concentrated on the heat dissipation around buried high-level radioactive wastes and the geomechanical consequences of their disposal. Near-field investigations cover the properties of water and gas release, radiolysis and corrosion. Further objectives of field experiments are the development and underground testing of a handling system for high-level wastes. The performance of an underground test disposal for such wastes is not only considered to be necessary for technical and scientific reasons but also for improving public acceptance of the concept of radioactive waste disposal. (author)

  17. Employee Recognition and Performance: A Field Experiment

    NARCIS (Netherlands)

    C. Bradler (Christiane); A.J. Dur (Robert); S. Neckermann (Susanne); J.A. Non (Arjan)

    2013-01-01

    textabstractThis paper reports the results from a controlled field experiment designed to investigate the causal effect of public recognition on employee performance. We hired more than 300 employees to work on a three-hour data-entry task. In a random sample of work groups, workers unexpectedly

  18. Employee recognition and performance: A field experiment

    NARCIS (Netherlands)

    Bradler, C.; Dur, R.; Neckermann, S.; Non, J.A.

    2013-01-01

    This paper reports the results from a controlled field experiment designed to investigate the causal effect of public recognition on employee performance. We hired more than 300 employees to work on a three-hour data-entry task. In a random sample of work groups, workers unexpectedly received

  19. Response of rice to inoculation with plant growth promoting rhizobacteria in control lab environment and field experiment

    International Nuclear Information System (INIS)

    Ahmed, B.

    2014-01-01

    The present study was conducted to evaluate the effects of bacterial inoculation on different growth parameters of rice variety JP-5. Three bacterial strains (Azospirillum brasilense R1, Azospirillum lipoferum RSWT1 and Pseudomonas Ky1) were used to inoculate rice varietyJP-5 at control lab environment and field. Plant growth promotion was observed in all inoculated treatments over non-inoculated, which was evident from increase in root area, root length, number of tillers, straw and grain yields and total weight of plant. Azospirillum brasilense R1 was more effective in plant growth promotion than other strains and showed 19% increase in the straw weight and 39.5% increase in grain weight. Inoculation with Azospirillum lipoferum RSWT1 and Pseudomonas Ky1 increased grain weight by 18.5% and 13.8% respectively. The study revealed that beneficial strains of PGPR can be used as biofertilizer for rice. (author)

  20. Tango for experiment control

    International Nuclear Information System (INIS)

    Meyer, J.; Claustre, L.; Petitdemange, S.; Svensson, O.; Götz, A.; Coutinho, T.; Klora, J.; Picca, F.; Ounsy, M.; Buteau, A.

    2012-01-01

    The Tango control system framework allows you to control an accelerator complex as well as single equipment. The framework contains the communication bus with the standard communication modes (synchronous, asynchronous, event driven) as well as the basic hardware access modules, GUI tools and development kits, bindings to commercial products (LabView, Matlab, IgorPro) and services (administration, archiving, access control) to set up a control system. Tango was mainly developed by several synchrotron light sources that have to support not only the accelerator complex but also a lot of experimental end stations. For synchrotron experiments we have to control the whole process from basic hardware access over data taking to data analysis. This paper describes in the first part the special features of Tango allowing flexible experiment control. The dynamic configuration, the rapid hardware interface development and the sequencing and scanning framework are some examples. The second part gives an overview of some packages developed in the Tango community for experiment control: A HKL library for diffraction computation and diffractometer control, a library to control 2D detectors and a data analysis workbench with workflow engine for on-line and off-line data analysis. These packages are not part of Tango and can be used with other control systems. (author)

  1. On the control of magnetic perturbing field onboard landers: the Magnetometer Protection program for the ESA ExoMars/Humboldt MSMO magnetometer experiment

    DEFF Research Database (Denmark)

    Menvielle, M.; Primdahl, Fritz; Brauer, Peter

    to planetary research. The major difficulty in implementing a magnetometer experiment onboard a lander is to achieve at acceptable costs a good Magnetometer Protection, namely to control the perturbing magnetic field generated by the lander during operations at the planetary surfa ce, so as to achieve...... scientific payload in the frame of the ESA ExoMars mission. Experience from previous missions constitutes the background for the MSMO Magnetometer Protection strategy. DC and AC lander generated magnetic perturbations are discussed, with particular attention to those related to solar generators. Emphasis...... and very resource consuming....

  2. Water movement through a shallow unsaturated zone in an inland arid region: Field drip irrigation experiment under matrix potential control

    Science.gov (United States)

    Zhou, T.; Han, D.; Song, X.

    2017-12-01

    It is vital to study soil water movement in unsaturated zone for evaluating and improving current irrigation mode for prevention and control of soil secondary salinization, especially in inland arid area, where is characterized by strong evaporation, poor drainage system and shallow water table depth. In this study, we investigated the applicability of drip irrigation under matrix potential control during cotton growth seasons in an inland arid region of northwest China. Combined physical observation with stable isotopes tracing method, we studied soil water flow system and recharge sources of shallow groundwater in heavy (Pilot 1) and light (Pilot 2) saline-alkali cotton fields. Evaporation depths (about 50-60 cm) are about the same for both pilots, but infiltration depths (about 60 cm for Pilot 1 and 150 cm for Pilot 2) are very different due to different soil texture, soil structure and soil salt content. Middle layer (about 100 cm thick) is a critical barrier for water exchange between surface and deep layer. Irrigation water is the major source (about 79.6% for Pilot 1 and 81.6% for Pilot 2), while evapotranspiration is the major sink (about 80.7% for Pilot 1 and 83.1% for Pilot 2) of unsaturated zone. The increase of soil water storage is not enough to make up the water shortage of middle layer and thus drip irrigation water doesn't recharge into groundwater for both pilots. Water table rise (about 60 cm for Pilot 1 and 50 cm for Pilot 2) could be caused by lateral groundwater flow instead of vertical infiltration. This irrigation mode could retard the water table rise in this region. However, improving horizontal drainage system may be indispensable for sustainable agriculture development. The study can provide important basis for soil secondary salinization prevention and agricultural water management in inland arid areas.

  3. Magnetic field line reconnection experiments

    International Nuclear Information System (INIS)

    Gekelman, W.; Stenzel, R.L.; Wild, N.

    1982-01-01

    A laboratory experiment concerned with the basic physics of magnetic field line reconnection is discussed. Stimulated by important processes in space plasmas and anomalous transport in fusion plasmas the work addresses the following topics: Dynamic magnetic fields in a high beta plasma, magnetic turbulence, plasma dynamics and energy transport. First, the formation of magnetic neutral sheets, tearing and island coalescence are shown. Nonstationary magnetic fluctuations are statistically evaluated displaying the correlation tensor in the #betta#-k domain for mode identification. Then, the plasma properties are analyzed with particular emphasis on transport processes. Although the classical fluid flow across the separatrix can be observed, the fluctuation processes strongly modify the plasma dynamics. Direct measurements of the fluid force density and ion acceleration indicate the presence of an anomalous scattering process characterized by an effective scattering tensor. Turbulence also enhances the plasma resistivity by one to two orders of magnitude. Measurements of the three-dimensional electron distribution function using a novel energy analyzer exhibit the formation of runaway electrons in the current sheet. Associated micro-instabilities are observed. Finally, a macroscopic disruptive instability of the current sheet is observed. Excess magnetic field energy is converted at a double layer into particle kinetic energy and randomized through beam-plasma instabilities. These laboratory results are compared with related observations in space and fusion plasmas. (Auth.)

  4. The Kolar Gold Field experiment

    International Nuclear Information System (INIS)

    Sreekantan, B.V.

    1982-01-01

    Meson theory was propounded to explain the nuclear force which holds neutrons and protons inside the nucleus. Subsequently, quark theory was put forward to bring some order into an enormously large number of fundamental particles discovered in the hadron family. These two theories are briefly explained. The gravitational force, the electromagnetic force, the weak nuclear force and the strong nuclear force are the basic forces which determine the behaviour of fundamental particles when they are in close proximity. If the last three of the above-mentioned four forces are one or just different aspects of a single force, quarks and leptons can be mingled in the same theoretical framework indicating the non-conservation of baryon number and the spontaneous decay of the proton into leptons. In order to test the last possibility i.e. proton decay, an experiment has been set up in the Kolar Gold Field at a depth of 2300 metres in India. 1650 gas proportional counters are sandwiched between iron plates. The total amount of iron in the form of iron plates and walls of the counters is 140 tons. In this experiment, nuclei of iron are serving as the source of protons and neutrons and the depth eliminates the background events which mimic proton decay. The amount of iron used in the experiment i.e. 140 tons is more than enough to obtain evidence of 10 proton decay events in a year, assuming that the lifetime of proton is 10 30 years or below. (M.G.B.)

  5. Fladis field experiments. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, M.; Ott, S.

    1996-06-01

    The objective of the Fladis field experiments was to investigate dispersion of liquefied ammonia with equal attention to the near-source aerosol jet, the intermediate heavy gas dispersion phase, and the downstream transition to passive dispersion. The present report presents the sensor layout and gives an overview of the available experimental data. This is done for observations in a fixed frame of reference and relative to the instantaneous plume centre line. The moving frame statistics are expected to compare better with wind tunnel simulations and numerical models which do not include plume meandering. The plume mass flux is estimated from the observed plume profiles and compared to the release rate. Average surface concentrations are found with a special interpolation method, and this is used to study how the averaging period affects the plume footprint. The instantaneous plume is non-Gaussian, and this is demonstrated by Lidar measurements in the far field and thermocouple measurements in the near-source jet. Probability functions and a spatial correlation for the concentration are found. The heat budget of the plume shows signs of heat flux from the ground. The composition of the liquid aerosols was observed to change from almost pure ammonia to almost pure water. A new two-dimensional `shallow layer` type model SLAM is developed, and an existing `box` type model for heavy-gas dispersion on a uniform terrain is generalized. (au) 3 tabs., 19 ills., 29 refs.

  6. Employee Recognition and Performance: A Field Experiment

    OpenAIRE

    Bradler, Christiane; Dur, Robert; Neckermann, Susanne; Non, Arjan

    2014-01-01

    This discussion paper led to a publication in 'Management Science' . This paper reports the results from a controlled field experiment designed to investigate the causal effect of unannounced, public recognition on employee performance. We hired more than 300 employees to work on a three-hour data-entry task. In a random sample of work groups, workers unexpectedly received recognition after two hours of work. We find that recognition increases subsequent performance substantially, and particu...

  7. Control of slug damage to oilseed rape and wheat with imidacloprid seed dressings in laboratory and field experiments

    NARCIS (Netherlands)

    Simms, L.C.; Ester, A.; Wilson, M.J.

    2006-01-01

    Slugs are common pests of oilseed and cereal crops in Europe and are currently controlled using bait pellets that often fail to give adequate protection: Here we investigate the potential of the broad-spectrum insecticide imidacloprid, previously suggested to have activity against slugs, to control

  8. Field experiments using the rhabditid nematode Phasmarhabditis hermaphrodita or salt as control measures against slugs in green asparagus

    NARCIS (Netherlands)

    Ester, A.; Rozen, van K.; Molendijk, L.P.G.

    2003-01-01

    Green asparagus (Asparagus officinalis L.) crops are frequently damaged by the grey field slug (Deroceras reticulatum). Most damage occurs in the soil, although some asparagus spears are attacked above ground. In the Netherlands damage occurs especially during the first 5 weeks of harvesting, from

  9. Automating quantum experiment control

    Science.gov (United States)

    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.

  10. Review of WAG Field Experience

    DEFF Research Database (Denmark)

    Christensen, Jes Reimer; Stenby, Erling Halfdan; Skauge, A.

    2001-01-01

    well spacing is in the order of 1000 m. For the fields reviewed, a common trend for the successful injections is an increased oil recovery in the range of 5 to 10% of the oil initially in place (OIIP). Very few field trials have been reported as unsuccessful, but operational problems are often noted...

  11. The National Airborne Field Experiment Data Sets

    DEFF Research Database (Denmark)

    Walker, J. P.; Balling, Jan E.; Bell, M.

    2007-01-01

    The National Airborne Field Experiment's (NAFE) were a series of intensive experiments recently conducted in different parts of Australia. These hydrologic-focused experiments have been designed to answer a range of questions which can only be resolved through carefully planned and executed field...

  12. Field experience with two different vaccination strategies aiming to control infections with Actinobacillus pleuropneumoniae in a fattening pig herd

    Directory of Open Access Journals (Sweden)

    Sjölund Marie

    2010-03-01

    Full Text Available Abstract Background The prevalence of pleurisies recorded at slaughter is increasing in Sweden, and acute outbreaks of actinobacillosis that require antimicrobial treatments have become more frequent. As an increased use of antimicrobials may result in the development of antimicrobial resistance it is essential to develop alternative measures to control the disease. Vaccinations present an appealing alternative to antimicrobial treatments. The aim of this work was to evaluate the potential of two different vaccination strategies in a specialized fattening herd affected by actinobacillosis. Methods The study was conducted in a specialized fattening herd employing age segregated rearing in eight units. The herd suffered from infections caused by Actinobacillus pleuropneumoniae serotype 2, confirmed by necropsy and serology. The study included 54 batches of pigs grouped into five periods. Batches of pigs of the second period were vaccinated against actinobacillosis twice, and pigs in the fourth period were vaccinated three times. Batches of pigs of the first, third and fifth period were not vaccinated. Concentrations of serum antibodies to A. pleuropneumoniae and serum amyloid A (SAA were analysed and production data were recorded. Results Despite vaccinating, medical treatments were required to reduce the impact of the disease. The mean incidence of individual treatments for respiratory diseases during the rearing period ranged from 0 to 4.7 ± 1.8%, and was greatest during the triple vaccination period (period IV; p A. pleuropneumoniae serotype 2 in the absence of a SAA-response. The prevalence of pleuritis decreased from 25.4 ± 6.5% in the first period to 5.0 ± 3.7% in the fifth period (p Conclusions The vaccine did not effectively prevent clinical expression of A. pleuropneumoniae infections, but seroconversion to A. pleuropneumoniae in the absence of a SAA-response in a large number pigs indicated that the vaccine had activated the immune

  13. Jet Grouting. Control of execution and result parameters. Test fields - Experience in Chile; Jet Grouting. Control de parametros de ejecucion y de resultados. Campos de prueba-Experiencia en Chile

    Energy Technology Data Exchange (ETDEWEB)

    Ayarza, P. M.; Vukotic, G.

    2014-07-01

    This article emphasizes the importance of Test Fields in project that includes the Jet Grouting technique. In particular, the Chilean experience is analyzed, where the Jet Grouting was first introduced by Pilots Terratest S. A. in the year 2010, only, only in 2011 the first project using jet columns was constructed. The versatilely of this technique allows its use in a wide variety of projects, for example, soil capacity improvement, settlement control, reduction of soil permeability and other environmental applications. Currently, the most common applications are underpinning existing foundations, ground improvement, lateral support of excavations, hydraulic barriers, slope stabilization, liquefaction control, among others. The Jet Grouting is one of the most demanding soil improvement technique and requires excellence in designing and execution engineers and other involved specialist. It is therefore essential to ensure exhaustive control to the execution and final parameters, in order to check that the product- Jet Grouting element-have the design properties, and implement modifications if necessary. Many authors strongly advises that if there is no comparable experience and even if there is, a Test Field of Jet Grouting elements has to be executed in site. This field consists in a nearby area with similar geotechnical conditions of the project, where Jet Grouting test columns will be constructed. This Test Field will allow selecting the most effective execution parameters and verifying that the final product has he correct design properties. (Author)

  14. Experiments for obtaining field influence mass particles.

    CERN Document Server

    Yahalomi, E

    2010-01-01

    Analyzing time dilation experiments the existence of a universal field interacting with moving mass particles is obtained. It is found that mass particle changes its properties depend on its velocity relative to this universal scalar field and not on its velocity relative to the laboratory. High energy proton momentum, energy and mass were calculated obtaining new results. Experiments in high energy accelerators are suggested as additional proofs for the existence of this universal field. This universal field may explain some results of other high energy experiments.

  15. FFTF control system experience

    International Nuclear Information System (INIS)

    Warrick, R.P.

    1981-01-01

    The FFTF control systems provide control equipment for safe and efficient operation of the plant. For convenience, these systems will be divided into three parts for discussions: (1) Plant Protection System (PPS); (2) Plant Control System (PCS); and (3) General Observations. Performance of each of these systems is discussed

  16. Indirect Reciprocity; A Field Experiment.

    Science.gov (United States)

    van Apeldoorn, Jacobien; Schram, Arthur

    2016-01-01

    Indirect reciprocity involves cooperative acts towards strangers, either in response to their kindness to third parties (downstream) or after receiving kindness from others oneself (upstream). It is considered to be important for the evolution of cooperative behavior amongst humans. Though it has been widely studied theoretically, the empirical evidence of indirect reciprocity has thus far been limited and based solely on behavior in laboratory experiments. We provide evidence from an online environment where members can repeatedly ask and offer services to each other, free of charge. For the purpose of this study we created several new member profiles, which differ only in terms of their serving history. We then sent out a large number of service requests to different members from all over the world. We observe that a service request is more likely to be rewarded for those with a profile history of offering the service (to third parties) in the past. This provides clear evidence of (downstream) indirect reciprocity. We find no support for upstream indirect reciprocity (in this case, rewarding the service request after having previously received the service from third parties), however. Our evidence of downstream indirect reciprocity cannot be attributed to reputational effects concerning one's trustworthiness as a service user.

  17. Field Experience Study in a Traditional Setting.

    Science.gov (United States)

    Perenich, Theresa A.

    1978-01-01

    A field experience in fashion marketing for Kansas State University students is described. The functions and responsibilities of the coordinator, the student, and the departmental supervisor are outlined, along with the evaluation processes used. (Author/LBH)

  18. Experience in landslide control

    Energy Technology Data Exchange (ETDEWEB)

    Koz' min, L S

    1983-06-01

    The problems of slope stability in the Krasnoyarskugol' surface mines are discussed. Methods used for slide prevention and slide control from 1977 to 1982 are analyzed. Landslides were caused by weathering of the argillite layer in the coal seam roof. Sliding plane was parallel to the coal seam roof. At a later stage of landslide prevention sliding planes were in the coal seam floor (which consisted of weak rock layers). Range of landslides was evaluated. Losses caused by landslides were discussed: working time losses, losses of coal, damaged equipment. Landslide hazards were controlled by reducing slope angle and by changing cut geometry. Cross section of the cut with a spoil bank prone to landslides is shown in a scheme. Reducing angle of slope inclination, using strong rock layers as the spoil bank base and changing cut geometry eliminated landslides in 1982. Recommendations on landslide control in coal surface mines with layers of weak rocks influenced by weathering are made.

  19. Global field experiments for potato simulations

    DEFF Research Database (Denmark)

    Raymundo, Rubí; Asseng, Senthold; Prasad, Rishi

    2018-01-01

    A large field potato experimental dataset has been assembled for simulation modeling. The data are from temperate, subtropical, and tropical regions across the world and include 87 experiments with 204 treatments. Treatments include nitrogen fertilizer, irrigation, atmospheric CO2 levels, tempera......A large field potato experimental dataset has been assembled for simulation modeling. The data are from temperate, subtropical, and tropical regions across the world and include 87 experiments with 204 treatments. Treatments include nitrogen fertilizer, irrigation, atmospheric CO2 levels...

  20. Field Experiments in Behavioral and Public Economics

    OpenAIRE

    Bhanot, Syon Pandya

    2015-01-01

    The three essays in this dissertation present field experiments exploring phenomena in behavioral and public economics in real-world settings. The first essay outlines a field experiment that uses mailers with peer rank information to motivate water conservation. The essay contributes some of the first pieces of evidence on how comparisons with specific peers might influence behavior. The main finding is that while competitive framing of peer information has positive impacts on efficient h...

  1. Using Case Studies to Enrich Field Experience.

    Science.gov (United States)

    Florio-Ruane, Susan; Clark, Christopher M.

    1990-01-01

    This paper discusses the use of field experience in teacher education and how it can be augmented by phenomenological case studies. It summarizes a particular case study involving three teacher education classes, noting that reflective analysis of cases can prepare students to observe in the field. (SM)

  2. Control rod experiments in Racine

    International Nuclear Information System (INIS)

    Stanculescu, A.; Humbert, G.

    1981-09-01

    A survey of the control-rod experiments planned within the joint CEA/CNEN-DeBeNe critical experiment RACINE is given. The applicability to both heterogeneous and homogeneous large power LMFBR-cores is discussed. Finally, the most significant results of the provisional design calculations performed on behalf of the RACINE control-rod programme are presented

  3. Field experiments on airborne moisture transport

    NARCIS (Netherlands)

    Oldengarm, J.; Gids, W.F. de

    1990-01-01

    Within the framework of the Dutch participation in the IEA Annex XIV “Condensation” field experiments have been carried out to study airbome moisture transport in realistic circumstances. The experiments were done in an unoccupied 3-story dwelling in Leidschendam in the Netherlands. Some of the

  4. A Field Experiment in Motivating Employee Ideas

    NARCIS (Netherlands)

    M. Gibbs (Michael); S. Neckermann (Susanne); C. Siemroth (Christoph)

    2014-01-01

    markdownabstract__Abstract__ We study the effects of a field experiment designed to motivate employee ideas, at a large technology company. Employees were encouraged to submit ideas on process and product improvements via an online system. In the experiment, the company randomized 19 account

  5. Magnetic field experiment on the SUNSAT satellite

    Science.gov (United States)

    Kotzé, P. B.; Langenhoven, B.; Risbo, T.

    2002-03-01

    On Tuesday 23 February 1999, at 10:29 UTC, SUNSAT was launched into an 857×655 km, 96.47° polar orbit on a Boeing-Delta II rocket from Vandenberg Air Force Base in California, USA. Both SUNSAT and Ørsted were NASA-sponsored secondary payloads accompanying the USA Air Force Argos satellite. In the process it became South Africa's (and Africa's) first satellite in space. Although sponsored by several private industrial organisations, it is essentially a student project with more than 96 graduate students in the Department of Electronic and Electrical Engineering at the University of Stellenbosch providing the majority of SUNSAT's engineering development and operation since 1992. This paper reports on the magnetic field experiment on board the Sunsat satellite, consisting of two fluxgate magnetometers, called Orimag and Scimag, both built and calibrated by the Hermanus Magnetic Observatory. Orimag is mainly used for orientation control purposes on SUNSAT, while Scimag, mounted on a boom of 2.2 m is designed to perform geomagnetic field observations, employing standard navigation fluxgate technology.

  6. Field bus technology in accelerator control systems

    International Nuclear Information System (INIS)

    Tang Shuming

    1999-01-01

    Since eighties to now, the computer technology, network communication and ULSI technology have been developing rapidly. The level of control for industries and scientific experiments has been upgraded accordingly, so as to meet the increasing requirements for automation. The control systems become more complicated; the devices in control systems become more and more intelligent. However the cost of DCS (Distributed Control System) is quite expensive and the period of system integration is very long. More than ten measurement results for two methods defined in the world, in order to get inter operability of intelligent devices and reduce the costs. The author presents the development trend of fieldbuses briefly and describes the main performances of CAN, LONWORKS, WOLDFIP and PROFIBUS which are mainly used in the world today. The author proposes that the field bus technology will be introduced into the accelerator control systems in the country

  7. Global field experiments for potato simulations

    NARCIS (Netherlands)

    Raymundo, Rubi; Asseng, Senthold; Prasad, Rishi; Kleinwechter, Ulrich; Condori, Bruno; Bowen, Walter; Wolf, Joost; Olesen, Jørgen E.; Dong, Qiaoxue; Zotarelli, Lincoln; Gastelo, Manuel; Alva, Ashok; Travasso, Maria; Arora, Vijay

    2018-01-01

    A large field potato experimental data set has been assembled for simulation modeling. The data are from temperate, subtropical, and tropical regions across the world and include 87 experiments with 204 treatments. Treatments include nitrogen fertilizer, irrigation, atmospheric CO2 levels,

  8. Random Assignment: Practical Considerations from Field Experiments.

    Science.gov (United States)

    Dunford, Franklyn W.

    1990-01-01

    Seven qualitative issues associated with randomization that have the potential to weaken or destroy otherwise sound experimental designs are reviewed and illustrated via actual field experiments. Issue areas include ethics and legality, liability risks, manipulation of randomized outcomes, hidden bias, design intrusiveness, case flow, and…

  9. Soil treatment technologies: Comparison of field experiences

    International Nuclear Information System (INIS)

    Hodges, H.I.; Jackson, D.W.; Kline, K.

    1992-01-01

    A number of on-site soil treatment technologies are available for closure of oil-field waste pits, leaking underground storage tank (LUST) sites, and general hydrocarbon contamination. This paper will contrast Separation Systems Consultants, Inc.'s (SSCI's) field experiences with the following soil restoration techniques: (1) Land Treatment using indigenous microbes; (2) Land Farming using commercial microbes; (3) Low Temperature Thermal Treatment; (4) Solidification. The technologies will be contrasted in terms of regulatory constraints and requirements, key set-up and maintenance consideration, selection factors. Included in the regulatory contrast is the authors' perception of regulatory attitudes toward the techniques. Because this paper is based on actual field experience and projects, the practical aspects of making the technologies work is emphasized

  10. Reproducibility, controllability, and optimization of LENR experiments

    Energy Technology Data Exchange (ETDEWEB)

    Nagel, David J. [The George Washington University, Washington DC 20052 (United States)

    2006-07-01

    Low-energy nuclear reaction (LENR) measurements are significantly, and increasingly reproducible. Practical control of the production of energy or materials by LENR has yet to be demonstrated. Minimization of costly inputs and maximization of desired outputs of LENR remain for future developments. The paper concludes by underlying that it is now clearly that demands for reproducible experiments in the early years of LENR experiments were premature. In fact, one can argue that irreproducibility should be expected for early experiments in a complex new field. As emphasized in the paper and as often happened in the history of science, experimental and theoretical progress can take even decades. It is likely to be many years before investments in LENR experiments will yield significant returns, even for successful research programs. However, it is clearly that a fundamental understanding of the anomalous effects observed in numerous experiments will significantly increase reproducibility, improve controllability, enable optimization of processes, and accelerate the economic viability of LENR.

  11. Reproducibility, controllability, and optimization of LENR experiments

    International Nuclear Information System (INIS)

    Nagel, David J.

    2006-01-01

    Low-energy nuclear reaction (LENR) measurements are significantly, and increasingly reproducible. Practical control of the production of energy or materials by LENR has yet to be demonstrated. Minimization of costly inputs and maximization of desired outputs of LENR remain for future developments. The paper concludes by underlying that it is now clearly that demands for reproducible experiments in the early years of LENR experiments were premature. In fact, one can argue that irreproducibility should be expected for early experiments in a complex new field. As emphasized in the paper and as often happened in the history of science, experimental and theoretical progress can take even decades. It is likely to be many years before investments in LENR experiments will yield significant returns, even for successful research programs. However, it is clearly that a fundamental understanding of the anomalous effects observed in numerous experiments will significantly increase reproducibility, improve controllability, enable optimization of processes, and accelerate the economic viability of LENR

  12. [Damage control in field surgery].

    Science.gov (United States)

    Samokhvalov, I M; Manukovskiĭ, V A; Badalov, V I; Severin, V V; Golovko, K P; Denisenko, V V

    2011-09-01

    Damage control surgery (DCS) is an important option in the store of war surgery and surgery of trauma. The main purpose of our investigation was to specify the percentage of the injured who need DCS. We performed retrospective study of the patients in the combat operations in Chechnya (1994-2002) and in peacetime (2005-2010). Total lethality in group with the standard surgical approach was 62.3%. It was significantly higher than the lethality in group of patients who underwent DCS - 50.0% (p < 0.05). Thus, the experience of DCS in War Surgery Department confirms that DCS is perspective tendency in treatment of patients with severe and extremely severe trauma, and allows decreasing lethality in 12.3%.

  13. Utilizing Urban Environments for Effective Field Experiences

    Science.gov (United States)

    MacAvoy, S. E.; Knee, K.

    2014-12-01

    Research surveys suggest that students are demanding more applied field experiences from their undergraduate environmental science programs. For geoscience educators at liberal arts colleges without field camps, university vehicles, or even geology departments, getting students into the field is especially rewarding - and especially challenging. Here, we present strategies that we have used in courses ranging from introductory environmental science for non-majors, to upper level environmental methods and geology classes. Urban locations provide an opportunity for a different type of local "field-work" than would otherwise be available. In the upper-level undergraduate Environmental Methods class, we relied on a National Park area located a 10-minute walk from campus for most field exercises. Activities included soil analysis, measuring stream flow and water quality parameters, dendrochronology, and aquatic microbe metabolism. In the non-majors class, we make use of our urban location to contrast water quality in parks and highly channelized urban streams. Here we share detailed lesson plans and budgets for field activities that can be completed during a class period of 2.5 hours with a $75 course fee, show how these activities help students gain quantitative competency, and provide student feedback about the classes and activities.

  14. The FIELDS experiment for Solar Probe Plus

    Science.gov (United States)

    Bale, S.; Spp/Fields Team

    2010-12-01

    Many of our basic ideas on the plasma physics of acceleration, energy flow, and dissipation, and structure of the solar wind have never been rigorously confronted by direct experimental measurements in the region where these processes are actually occurring. Although Alfven waves, shocks, and magnetic reconnection are often invoked as heating mechanisms, there have never been any direct measurements of Alfvenic waves nor the associated Poynting flux nor any measurements of ion or electron kinetic energy flux in the region from 10 R_s to 30 R_s where the final stages of wind acceleration are believed to occur. The radial profiles of both slow and fast solar wind acceleration are based on remote-sensing measurements and have been obtained for only a few selected events. Thus, the spatial radial and perpendicular scales of the acceleration process have been averaged by line-of-sight effects and the possibility of intense localized acceleration cannot be ruled out. The Solar Probe Plus (SPP) mission calls for the high quality fields and particles measurements required to solve the coronal heating and wind acceleration problem. The SPP 'FIELDS' experiment measures the electric and magnetic fields fundamental to the plasma physics of the structured and turbulent solar wind, flux ropes, collisionless shocks, and magnetic reconnection. FIELDS will make the first-ever measurements of the DC/Low-Frequency electric field inside of 1 AU allowing for in situ, high cadence measurements of the Poynting vector, the Elsasser variables, and E/B diagnostics of the wave spectrum to fce in the solar wind. SPP/FIELDS measures the radio wave (type III and II) signatures of microflares, energized electrons, and CME propagation. SPP/ FIELDS measures the plasma electron density to ~2% accuracy and the core electron temperature to ~5-10% accuracy more than 90% of the time at perihelion. FIELDS will also measure the in situ density fluctuation spectrum and structures at a very high cadence (

  15. Physical modeling and monitoring of the process of thermal-erosion of an ice-wedge during a partially-controlled field experiment (Bylot Island, NU, Canada)

    Science.gov (United States)

    Godin, E.; Fortier, D.

    2013-12-01

    Syngenetic ice-wedges polygons are widespread periglacial features of the Arctic. On Bylot Island, Nunavut, Canada, numerous thermo-erosion gullies up to several 100's m in length developed in polygonal wetlands during the last decades. These gullies contributed to drainage of these wetlands and changed dramatically local ecological conditions. Concentrated and repeated snowmelt surface runoff infiltrated frost cracks, where convective heat transfer between flowing water and ice initiated piping in ice wedges leading to the rapid development of tunnels and gullies in the permafrost (Fortier D. et al., 2007). We conducted field experiments to quantify the convection process and speed of ice wedges ablation. The experiments were accomplished between the 23/06/2013 and the 05/07/2013 over A; an exposed sub-horizontal ice-wedge surface and B; a tunnel in an ice-wedge crack. The ice was instrumented with graduated sticks to calculate the ice ablation following the flow of a defined amount of water. A fixed quantity of water obtained from a nearby waterfall was diverted over the ice through a PVC pipe. Water temperature Wt (K), quantity Wq (L s-1 or m3 s-1), ice ablation rate Iar (m s-1) and convective heat transfer coefficient α (W m-2 K) were obtained during the 5 experiments. The objective of this paper is to quantify the heat transfer process from field measurements from an ice wedge under ablation and to compare with coefficients from previous researches and in the literature. For each experiment with the ice-surface scenario, water temperature varied between 280 K and 284 K. Discharge varied between 0.0001 and 0.0003 m3 s-1. Ablation rate varied between 1.8 * 10-5 and 0.0004 m s-1. Heat transfer coefficient varied between 706 and 11 655 W m-2 K and between 54 and 4802 W of heat was transferred to ice. For each experiment with the tunnel scenario, water temperature was 284 K × 1 K. Discharge was 0.0002 m3 s-1. Ablation rate varied between 0.0001 and 0.0003 m s-1

  16. ["Me? I'm just here, part of the world". A field experience on endemic disease control in Cansanção, Minas Gerais, Brazil].

    Science.gov (United States)

    Dias, R B

    1998-01-01

    This free-style article reports an experience with Chagas' disease control involving community participation in the Jequitinhonha Valley (Minas Gerais, Brazil) implemented during the 1980s and recently reevaluated. As an action-based participant research project, it was supported by the Socioeconomic TDR Committee (WHO/WB/UNDP) in the area of Popular Education. The main objective was to investigate the meaning of Chagas' disease from the community's perspective, seeking alternative control measures with their participation. Despite the extremely high prevalence of the disease, it was no perceived as a priority by the population, who were living in destitution and simply fighting for their very survival. Given this situation, Chagas' disease control was performed in an integrated manner, taking other community needs into account. The article suggests some forms of participation in the control of endemic diseases, taking into account the people's knowledge, focused on the "here and now" in an integrated vision of both their problems and their ability to mobilize behind concrete interests. Changes are also needed in the relationship between outside agents and the community, reciprocity in the involvement with community, a permanent attitude of listening and solidarity, a "self-diagnosis", and organization of population.

  17. Dynamic Incentive Effects of Relative Performance Pay: A Field Experiment

    NARCIS (Netherlands)

    J. Delfgaauw (Josse); A.J. Dur (Robert); J.A. Non (Arjan); W.J.M.I. Verbeke (Willem)

    2010-01-01

    textabstractWe conduct a field experiment among 189 stores of a retail chain to study dynamic incentive effects of relative performance pay. Employees in the randomly selected treatment stores could win a bonus by outperforming three comparable stores from the control group over the course of four

  18. 160 Gb/s all-optical packet switching field experiment

    DEFF Research Database (Denmark)

    Dorren, H.J.S.; Herrera, J.; Raz, O.

    2007-01-01

    We discus an all-optical packet switching experiment over 110 km of field installed optical fiber. The switching node is controlled by solely photonic control circuits.......We discus an all-optical packet switching experiment over 110 km of field installed optical fiber. The switching node is controlled by solely photonic control circuits....

  19. Across the Arctic Teachers Experience Field Research

    Science.gov (United States)

    Warnick, W. K.; Warburton, J.; Wiggins, H. V.; Marshall, S. A.; Darby, D. A.

    2005-12-01

    From studying snow geese on the North Slope of Alaska to sediment coring aboard the U.S. Coast Guard Cutter Healy in the Arctic Ocean, K-12 teachers embark on scientific expeditions as part of a program that strives to make science in the Arctic a "virtual" reality. In the past two years, seventeen K-12 teachers have participated in Teachers and Researchers Exploring and Collaborating (TREC), a program that pairs teachers with researchers to improve science education through arctic field experiences. TREC builds on the scientific and cultural opportunities of the Arctic, linking research and education through topics that naturally engage students and the wider public. TREC includes expeditions as diverse as studying plants at Toolik Field Station, a research facility located 150 miles above the Arctic Circle; climate change studies in Norway's Svalbard archipelago; studying rivers in Siberia; or a trans-arctic expedition aboard the USCGC Healy collecting an integrated geophysical data set. Funded by the National Science Foundation Office of Polar Programs, TREC offers educators experiences in scientific inquiry while encouraging the public and students to become active participants in the scientific inquiry by engaging them virtually in arctic research. TREC uses online outreach elements to convey the research experience to a broad audience. While in remote field locations, teachers and researchers interact with students and the public through online seminars and live calls from the field, online journals with accompanying photos, and online bulletin boards. Since the program's inception in 2004, numerous visitors have posted questions or interacted with teachers, researchers, and students through the TREC website (http://www.arcus.org/trec). TREC teachers are required to transfer their experience of research and current science into their classroom through the development of relevant activities and resources. Teachers and researchers are encouraged to participate

  20. Improvement of RFX performances by field and impurity control

    International Nuclear Information System (INIS)

    Buffa, A.; Gnesotto, F.

    1995-01-01

    The Reverse Field Pinch experiment RFX has been operated since 1992 with the principal objective of extending the knowledge of RFP confinement to larger dimensions and higher plasma currents. Experiments have been run between 500 and 900 kA; confinement parameters are mainly determined by magnetic field quality and plasma density behavior. Significant improvements were obtained by feedback controlling the poloidal field configuration and by reducing the impurities produced by plasma-wall interactions

  1. Airborne ground penetrating radar: practical field experiments

    CSIR Research Space (South Africa)

    Van Schoor, Michael

    2013-10-01

    Full Text Available 1. All the radargrams were processed by applying basic GPR processing steps, which included a time zero correction, a dewow filter and the application of an automatic gain control (AGC) function. No migration was applied so as to preserve.... Suitable automatic detection algorithm could potentially be employed if target responses with specific characteristics are being sought. The results from this experiment are likely to be frequency independent. If so, a low frequency GPR system – say...

  2. Field experiences using acrolein (2-propenal) for control of SRB and MIC in an offshore production flowline and onshore production facility in Western Australia

    Energy Technology Data Exchange (ETDEWEB)

    Shield, M.; Charlesworth, M.; Paakkonen, S.

    2006-03-15

    Acrolein, 2-propenal, was evaluated as a microbiocide for control of sulphate-reducing bacteria (SRB) in a sub-sea pipeline and an onshore process plant operated by ChevronTexaco Australia Pty Ltd (CVX) in the North West Shelf (NWS) of Australia. An initial trial compared the efficacy of acrolein with that of a glutaraldehyde, quaternary amine blend (GQB) for control of SRB implicated in microbiologically induced corrosion (MIC) of the sub-sea pipeline. Based on improved performance, acrolein subsequently replaced the GQB for routine microbiocide treatment of the pipeline. In addition, a plant trial assessed the impact of acrolein supplementation of the existing tetrakishydroxy-methyl phosphonium sulphate (THPS) microbiocide programme for control of SRB in process plant operations. This paper overviews both the pipeline and plant trials as well as the programme implementation of acrolein microbiocide for routine pipeline treatment. In addition to an improved performance and safety profile, complete conversion of the microbiocide programme to acrolein is projected to result in direct savings of 40%, with further potential for secondary operational cost savings. on behalf of Ampol and Caltex; and, in 1964, the company discovered oil in commercial quantities on Barrow Island (BWI) off the North West Shelf of Australia. Today, CVX continues hydrocarbon production operations on BWI with over 300 million barrels produced since inception. BWI volumes have been augmented since 1989 through hydrocarbon recovery operations near Thevenard Island (TVI), a small island located 25 km north-north west of Onslow. To date, more than 146 million barrels have been processed through facilities on TVI. With the process plant covering only a small corner of the island, the majority of land mass on TVI is classified as a nature reserve for the protection of plants and animals. Important wildlife found on the island include green and flatback turtles that nest on the islands beaches. In

  3. A ``Cyber Wind Facility'' for HPC Wind Turbine Field Experiments

    Science.gov (United States)

    Brasseur, James; Paterson, Eric; Schmitz, Sven; Campbell, Robert; Vijayakumar, Ganesh; Lavely, Adam; Jayaraman, Balaji; Nandi, Tarak; Jha, Pankaj; Dunbar, Alex; Motta-Mena, Javier; Craven, Brent; Haupt, Sue

    2013-03-01

    The Penn State ``Cyber Wind Facility'' (CWF) is a high-fidelity multi-scale high performance computing (HPC) environment in which ``cyber field experiments'' are designed and ``cyber data'' collected from wind turbines operating within the atmospheric boundary layer (ABL) environment. Conceptually the ``facility'' is akin to a high-tech wind tunnel with controlled physical environment, but unlike a wind tunnel it replicates commercial-scale wind turbines operating in the field and forced by true atmospheric turbulence with controlled stability state. The CWF is created from state-of-the-art high-accuracy technology geometry and grid design and numerical methods, and with high-resolution simulation strategies that blend unsteady RANS near the surface with high fidelity large-eddy simulation (LES) in separated boundary layer, blade and rotor wake regions, embedded within high-resolution LES of the ABL. CWF experiments complement physical field facility experiments that can capture wider ranges of meteorological events, but with minimal control over the environment and with very small numbers of sensors at low spatial resolution. I shall report on the first CWF experiments aimed at dynamical interactions between ABL turbulence and space-time wind turbine loadings. Supported by DOE and NSF.

  4. Cultural adaptation in translational research: field experiences.

    Science.gov (United States)

    Dévieux, Jessy G; Malow, Robert M; Rosenberg, Rhonda; Jean-Gilles, Michèle; Samuels, Deanne; Ergon-Pérez, Emma; Jacobs, Robin

    2005-06-01

    The increase in the incidence of HIV/AIDS among minorities in the United States and in certain developing nations has prompted new intervention priorities, stressing the adaptation of efficacious interventions for diverse and marginalized groups. The experiences of Florida International University's AIDS Prevention Program in translating HIV primary and secondary prevention interventions among these multicultural populations provide insight into the process of cultural adaptations and address the new scientific emphasis on ecological validity. An iterative process involving forward and backward translation, a cultural linguistic committee, focus group discussions, documentation of project procedures, and consultations with other researchers in the field was used to modify interventions. This article presents strategies used to ensure fidelity in implementing the efficacious core components of evidence-based interventions for reducing HIV transmission and drug use behaviors and the challenges posed by making cultural adaptation for participants with low literacy. This experience demonstrates the importance of integrating culturally relevant material in the translation process with intense focus on language and nuance. The process must ensure that the level of intervention is appropriate for the educational level of participants. Furthermore, the rights of participants must be protected during consenting procedures by instituting policies that recognize the socioeconomic, educational, and systemic pressures to participate in research.

  5. 1. Introduction. 2. Laboratory experiments. 3. Field experiments. 4. Integrated field-laboratory experiments. 5. Panel recommendations

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    Some recommendations for the design of laboratory and field studies in marine radioecology are formulated. The difficulties concerning the comparability of various experimental methods used to measure the fluxes of radionuclides through marine organisms and ecosystems, and also the use of laboratory results to make predictions for the natural environment are discussed. Three working groups were established during the panel meeting, to consider laboratory experiments, field studies, and the design and execution of integrated laboratory and field studies respectively. A number of supporting papers dealing with marine radioecological experiments were presented

  6. Field dodder – How to control it?

    Directory of Open Access Journals (Sweden)

    Marija Sarić-Krsmanović

    2015-04-01

    Full Text Available Broad geographic distribution and spectrum of hosts make field dodder, Cuscuta campestris, one of the most widespread and most harmful pests among flowering parasitic plants. Field dodder may become a problem in vegetable nurseries (e.g. tomato, sweet pepper and cabbage or in potato or some other crop grown in plastic greenhouses. However, the most devastating damage comes from field dodder outbreaks in newly-established perennial legume crops (alfalfa, clover, etc., which are generally the preferred hosts of this parasitic flowering species. Apart from alfalfa and clover, an expansion of field dodder has been observed in recent years in sugar beet, too. Different measures are available for controlling field dodder, from preventive (pure seeding material, tolerant cultivars, etc., to mechanical removal (mowing and hand weeding to herbicide treatments. The most successful control of field dodder requires a systematic approach ensured through integrated protection, which contributes to a more effective control of parasitic flowering plants.

  7. Recent developments in radiation field control technology

    International Nuclear Information System (INIS)

    Wood, C.J.

    1995-01-01

    The U.S. nuclear power industry has been remarkably successful in reducing worker radiation exposures over the past ten years. There has been over a fourfold reduction in the person-rem incurred for each MW.year of electric power generated: from 1.8 in 1980, to only 0.39 person-rems in 1991 and 1992. Preliminary data for 1993 are even lower: approximately 0.37 person-rem.MW.year. Despite this substantial improvement, challenges for the industry remain. Individual exposure limits have been tightened in ICRP 60 and there will be increased requirements for special maintenance work as plants age, suggesting that vigorous efforts with be increased requirements for special maintenance work as plants age, suggesting that vigorous efforts will be required to meet the industry goals for 1995. Reducing out-of-core radiation fields offer the best chance of continuing the downward trend in exposures. To assist utilities select the most economic technology for their specific plants, EPRI has published a manual capturing worldwide operating experience with radiation-field control techniques (TR-100265). No one method will suffice, but implementing suitable combinations from this collection will enable utilities to achieve their exposure goals. Radiation reduction is generally cost-effective: outages are shorter, manpower requirements are reduced and work quality is improved. Despite the up front costs, the benefits over the following 1-3 years typically outweigh the expenses

  8. Recent developments in radiation field control technology

    Energy Technology Data Exchange (ETDEWEB)

    Wood, C.J. [Electric Power Research Institute, Palo Alto, CA (United States)

    1995-03-01

    The U.S. nuclear power industry has been remarkably successful in reducing worker radiation exposures over the past ten years. There has been over a fourfold reduction in the person-rem incurred for each MW.year of electric power generated: from 1.8 in 1980, to only 0.39 person-rems in 1991 and 1992. Preliminary data for 1993 are even lower: approximately 0.37 person-rem.MW.year. Despite this substantial improvement, challenges for the industry remain. Individual exposure limits have been tightened in ICRP 60 and there will be increased requirements for special maintenance work as plants age, suggesting that vigorous efforts with be increased requirements for special maintenance work as plants age, suggesting that vigorous efforts will be required to meet the industry goals for 1995. Reducing out-of-core radiation fields offer the best chance of continuing the downward trend in exposures. To assist utilities select the most economic technology for their specific plants, EPRI has published a manual capturing worldwide operating experience with radiation-field control techniques (TR-100265). No one method will suffice, but implementing suitable combinations from this collection will enable utilities to achieve their exposure goals. Radiation reduction is generally cost-effective: outages are shorter, manpower requirements are reduced and work quality is improved. Despite the up front costs, the benefits over the following 1-3 years typically outweigh the expenses.

  9. Load reduced control procedure for wind power plants. A holistic survey and experiences from field tests; Lastreduzierende Regelungsverfahren fuer Windenergieanlagen. Ein ganzheitlicher Ueberblick und Erfahrungen aus Feldversuchen

    Energy Technology Data Exchange (ETDEWEB)

    Shan, M.; Fischer, B.; Duckwitz, D. [Fraunhofer Institut fuer Windenergie und Energiesystemtechnik (IWES), Kassel (Germany)

    2013-06-01

    The control system of a wind turbine has a large impact on the structural dynamic loads of wind power plants. The contribution under consideration reports on the opportunities for an active reduction of fatigue loads and extreme loads for various mechanical components using the variables pitch angle and generator torque.

  10. Biocide leaching during field experiments on treated articles.

    Science.gov (United States)

    Schoknecht, Ute; Mathies, Helena; Wegner, Robby

    2016-01-01

    Biocidal products can be sources of active substances in surface waters caused by weathering of treated articles. Marketing and use of biocidal products can be limited according to the European Biocidal Products Regulation if unacceptable risks to the environment are expected. Leaching of active substances from treated articles was observed in field experiments to obtain information on leaching processes and investigate the suitability of a proposed test method. Leaching under weathering conditions proceeds discontinuously and tends to decrease with duration of exposure. It does not only mainly depend on the availability of water but is also controlled by transport processes within the materials and stability of the observed substances. Runoff amount proved to be a suitable basis to compare results from different experiments. Concentrations of substances are higher in runoff collected from vertical surfaces compared to horizontal ones, whereas the leached amounts per surface area are higher from horizontal surfaces. Gaps in mass balances indicate that additional processes such as degradation and evaporation may be relevant to the fate of active substances in treated articles. Leached amounts of substances were considerably higher when the materials were exposed to intermittent water contact under laboratory conditions as compared to weathering of vertically exposed surfaces. Experiences from the field experiments were used to define parameters of a procedure that is now provided to fulfil the requirements of the Biocidal Products Regulation. The experiments confirmed that the amount of water which is in contact with exposed surfaces is the crucial parameter determining leaching of substances.

  11. Hydrogeochemical and mineralogical effects of sustained CO2 contamination in a shallow sandy aquifer: A field-scale controlled release experiment

    DEFF Research Database (Denmark)

    Cahill, Aaron Graham; Marker, Pernille Aabye; Jakobsen, Rasmus

    2014-01-01

    A shallow aquifer CO2 contamination experiment was performed to investigate evolution of water chemistry and sediment alteration following leakage from geological storage by physically simulating a leak from a hypothetical storage site. In a carbonate-free aquifer, in western Denmark, a total...... of 1600 kg of gas phase CO2 was injected at 5 and 10 m depth over 72 days through four inclined injection wells into aeolian and glacial sands. Water chemistry was monitored for pH, EC, and dissolved element evolution through an extensive network of multilevel sampling points over 305 days. Sediment cores...... were taken pre and postinjection and analyzed to search for effects on mineralogy and sediment properties. Results showed the simulated leak to evolve in two distinct phases; an advective elevated ion pulse followed by increasing persistent acidification. Spatial and temporal differences in evolution...

  12. Programming the control of magnetic field measurements

    International Nuclear Information System (INIS)

    David, L.

    1998-01-01

    This paper gives a short review concerning the new NMR probe measurement control system. Then it presents the new program 'CYCLOCHAMP' attached to the magnetic field measurement which also allows to cycle the magnetic field inside the cyclotrons and to equilibrate it among the SSC sectors. (authors)

  13. Radio frequency wave experiments on the MST reversed field pinch

    International Nuclear Information System (INIS)

    Forest, C.B.; Chattopadhyay, P.K.; Nornberg, M.D.; Prager, S.C.; Thomas, M.A.; Harvey, R.W.; Ram, A.K.

    1999-04-01

    Experiments, simulations, and theory all indicate that the magnetic fluctuations responsible for the poor confinement in the reversed field pinch (RFP) can be controlled by altering the radial profile of the current density. The magnetic fluctuations in the RFP are due to resistive MHD instabilities caused by current profile peaking; thus confinement in the RFP is ultimately the result of a misalignment between inductively driven current profiles and the stable current profiles characteristic of the Taylor state. If a technique such as rf current drive can be developed to non-inductively sustain a Taylor state (a current profile linearly stable to all tearing modes), the confinement of the RFP and its potential as a reactor concept are likely to increase. Whether there is a self-consistent path from poor confinement to greatly improved confinement through current profile modification is an issue for future experiments to address if and only if near term experiments can demonstrate: (1) coupling to and the propagation of rf waves in RFP plasmas, (2) efficient current drive, and (3) control of the power deposition which will make it possible to control the current profile. In this paper, modeling results and experimental plans are presented for two rf experiments which have the potential of satisfying these three goals: high-n parallel lower hybrid (LH) waves and electron Bernstein waves (EBWs)

  14. Control of water infiltration into near surface low-level waste disposal units. Final report on field experiments at a humid region site, Beltsville, Maryland

    International Nuclear Information System (INIS)

    Schulz, R.K.; Ridky, R.W.; O'Donnell, E.

    1997-09-01

    This study''s objective was to assess means for controlling water infiltration through waste disposal unit covers in humid regions. Experimental work was carried out in large-scale lysimeters 21.34 m x 13.72 m x 3.05 m (70 ft x 45 ft x 10 ft) at Beltsville, Maryland. Results of the assessment are applicable to disposal of low-level radioactive waste (LLW), uranium mill tailings, hazardous waste, and sanitary landfills. Three kinds of waste disposal unit covers or barriers to water infiltration were investigated: (1) resistive layer barrier, (2) conductive layer barrier, and (3) bioengineering management

  15. COMPUTER CONTROL OF BEHAVIORAL EXPERIMENTS.

    Science.gov (United States)

    SIEGEL, LOUIS

    THE LINC COMPUTER PROVIDES A PARTICULAR SCHEDULE OF REINFORCEMENT FOR BEHAVIORAL EXPERIMENTS BY EXECUTING A SEQUENCE OF COMPUTER OPERATIONS IN CONJUNCTION WITH A SPECIALLY DESIGNED INTERFACE. THE INTERFACE IS THE MEANS OF COMMUNICATION BETWEEN THE EXPERIMENTAL CHAMBER AND THE COMPUTER. THE PROGRAM AND INTERFACE OF AN EXPERIMENT INVOLVING A PIGEON…

  16. Control of water infiltration into near surface LLW disposal units. Progress report on field experiments at a humid region site, Beltsville, Maryland: Volume 7

    International Nuclear Information System (INIS)

    Schulz, R.K.; Ridky, R.W.; O'Donnell, E.

    1994-12-01

    The project objective is to assess means for controlling waste infiltration through waste disposal unit covers in humid regions. Experimental work is being performed in large scale lysimeters (70 ft x 45 ft x 10 ft) at Beltsville, MD and results of the assessment are applicable to disposal of LLW, uranium mill tailings, hazardous waste, and sanitary landfills. Three concepts are under investigation: (1) resistive layer barrier, (2) conductive layer barrier, and bioengineering water management. The resistive layer barrier consists of compacted earth (clay). The conductive layer barrier is a special case of the capillary barrier and it requires a flow layer (e.g. fine sandy loam) over a capillary break. As long as unsaturated conditions are maintained water is conducted by the flow layer to below the waste. This barrier is most efficient at low flow rates and is thus best placed below a resistive layer barrier. Such a combination of the resistive layer over the conductive layer barrier promises to be highly effective provided there is no appreciable subsidence. Bioengineering water management is a surface cover that is designed to accommodate subsidence. It consists of impermeable panels which enhance run-off and limit infiltration. Vegetation is planted in narrow openings between panels to transpire water from below the panels. This system has successfully dewatered two lysimeters thus demonstrating that this procedure could be used for remedial action (drying out) existing water-logged disposal sites at low cost

  17. Field dodder (Cuscuta campestris) control with flumioxazin

    Science.gov (United States)

    Field dodder is an important weed in alfalfa grown for seed production, requiring stringent control to keep the alfalfa seed free of dodder seed contamination. Pendimethalin has been the primary tool used to control dodder in alfalfa seed production for over 25 years. Flumioxazin was recently regis...

  18. Strong field control of predissociation dynamics.

    Science.gov (United States)

    Corrales, María E; Balerdi, Garikoitz; Loriot, Vincent; de Nalda, Rebeca; Bañares, Luis

    2013-01-01

    Strong field control scenarios are investigated in the CH3I predissociation dynamics at the origin of the second absorption B-band, in which state-selective electronic predissociation occurs through the crossing with a valence dissociative state. Dynamic Stark control (DSC) and pump-dump strategies are shown capable of altering both the predissociation lifetime and the product branching ratio.

  19. Mean Field Type Control with Congestion

    Energy Technology Data Exchange (ETDEWEB)

    Achdou, Yves, E-mail: achdou@ljll.univ-paris-diderot.fr; Laurière, Mathieu [Univ. Paris Diderot, Sorbonne Paris Cité, Laboratoire Jacques-Louis Lions, UMR 7598, UPMC, CNRS (France)

    2016-06-15

    We analyze some systems of partial differential equations arising in the theory of mean field type control with congestion effects. We look for weak solutions. Our main result is the existence and uniqueness of suitably defined weak solutions, which are characterized as the optima of two optimal control problems in duality.

  20. Control of water infiltration into near surface LLW disposal units. Progress report on field experiments at a humid region site, Beltsville, Maryland: Volume 8

    International Nuclear Information System (INIS)

    Schulz, R.K.; Ridky, R.W.

    1995-04-01

    This study's objective is to assess means for controlling water infiltration through waste disposal unit covers in humid regions. Experimental work is being performed in large-scale lysimeters 21.34 m x 13.72 m x 3.05 m (75 ft x 45 ft x 10 ft) at Beltsville, Maryland. Results of the assessment are applicable to disposal of low-level radioactive waste (LLW), uranium mill tailings, hazardous waste, and sanitary landfills. Three kinds of waste disposal unit covers or barriers to water infiltration are being investigated: (1) resistive layer barrier, (2) conductive layer barrier, and (3) bioengineering management. The resistive layer barrier consists of compacted earthen material (e.g., clay). The conductive layer barrier consists of a conductive layer in conjunction with a capillary break. As long as unsaturated flow conditions are maintained, the conductive layer will wick water around the capillary break. Below-grade layered covers such as (1) and (2) will fail if there is appreciable subsidence of the cover, and remedial action for this kind of failure will be difficult. A surface cover, called bioengineering management, is meant to overcome this problem. The bioengineering management surface barrier is easily repairable if damaged by subsidence; therefore, it could be the system of choice under active subsidence conditions. The bioengineering management procedure also has been shown to be effective in dewatering saturated trenches and could be used for remedial action efforts. After cessation of subsidence, that procedure could be replaced by a resistive layer barrier or, perhaps even better, by a resistive layer barrier/conductive layer barrier system. The latter system would then give long-term effective protection against water entry into waste without institutional care

  1. Control of water infiltration into near surface LLW disposal units: Progress report on field experiments at a humid region site, Beltsville, Maryland

    International Nuclear Information System (INIS)

    Schulz, R.K.; Ridky, R.W.

    1996-08-01

    This study's objective is to assess means for controlling water infiltration through waste disposal unit covers in humid regions. Experimental work is being performed in large-scale lysimeters 21.34 m x 13.72 m x 3.05 m (70 ft x 45 ft x 10 ft) at Beltsville, Maryland. Results of the assessment are applicable to disposal of low-level radioactive waste (LLW), uranium mill tailings, hazardous waste, and sanitary landfills. Three kinds of waste disposal unit covers or barriers to water infiltration are being investigated: (1) resistive layer barrier, (2) conductive layer barrier, and (3) bioengineering management. The resistive layer barrier consists of compacted earthen material (e.g., clay). The conductive layer barrier consists of a conductive layer in conjunction with a capillary break. As long as unsaturated flow conditions are maintained, the conductive layer will wick water around the capillary break. Below-grade layered covers such as (1) and (2) will fail if there is appreciable subsidence of the cover, and remedial action for this kind of failure will be difficult. A surface cover, called bioengineering management, is meant to overcome this problem. The bioengineering management surface barrier is easily repairable if damaged by subsidence; therefore, it could be the system of choice under active subsidence conditions. The bioengineering management procedure also has been shown to be effective in dewatering saturated trenches and could be used for remedial action efforts. After cessation of subsidence, that procedure could be replaced by a resistive layer barrier or, perhaps even better, by a resistive layer barrier/conductive layer barrier system. The latter system would then give long-term effective protection against water entry into waste without institutional care

  2. Control of water infiltration into near surface LLW disposal units-progress report on field experiments at a humid region site, Beltsville, Maryland

    International Nuclear Information System (INIS)

    O'Donnell, E.; Ridky, R.W.; Schulz, R.K.

    1994-01-01

    The study's objective is to assess means for controlling water infiltration through waste disposal unit covers in humid regions. Experimental work is being performed in large-scale lysimeters (75'x45'x10') at Beltsville, MD, and results of the assessment are applicable to disposal of low-level radioactive waste (LLW), uranium mill tailings, hazardous waste, and sanitary landfills. Three kinds of waste disposal unit covers or barriers to water infiltration are being investigated. They are: (1) resistive layer barrier, (2) conductive layer barrier, and (3) bioengineering management. The conductive layer barrier consists of a conductive layer in conjunction with a capillary break. As long as unsaturated flow conditions are maintained, the conductive layer will wick water around the capillary break. Below-grade layered covers such as (1) and (2) will fail if there is appreciable subsidence of the cover. Remedial action for this kind of failure will be difficult. A surface cover, called bioengineering management, is meant to overcome this problem. The bioengineering management surface barrier is easily repairable if damaged by subsidence; therefore, it could be the system of choice under active subsidence conditions. The bioengineering management procedure also has been shown to be effective in dewatering saturated trenches and could be used for remedial action efforts. After cessation of subsidence, that procedure could be replaced by a resistive layer barrier, or perhaps even better, a resistive layer barrier/conductive layer barrier system. This latter system would then give long-term effective protection against water entry into waste and without institutional care

  3. Experiments of Accuracy Air Ion Field Measurement

    Czech Academy of Sciences Publication Activity Database

    Bartušek, Karel; Fiala, P.; Jirků, T.; Kadlecová, E.

    2007-01-01

    Roč. 3, č. 8 (2007), s. 1330-1333 ISSN 1931-7360 Institutional research plan: CEZ:AV0Z20650511 Keywords : air ion field * gerdien condenser * picoampermeter Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  4. Cockle Field Caging Experiment Data (2014)

    Data.gov (United States)

    U.S. Environmental Protection Agency — To determine whether differences in cockle density or qualitative burial depth observed during the 2014 field survey were affected by green macroalgal (GMA) mats, we...

  5. Field Trips as Valuable Learning Experiences in Geography Courses

    Science.gov (United States)

    Krakowka, Amy Richmond

    2012-01-01

    Field trips have been acknowledged as valuable learning experiences in geography. This article uses Kolb's (1984) experiential learning model to discuss how students learn and how field trips can help enhance learning. Using Kolb's experiential learning theory as a guide in the design of field trips helps ensure that field trips contribute to…

  6. Control of water infiltration into near surface LLW disposal units - Progress report on field experiments at a humid region site, Beltsville, Maryland

    Energy Technology Data Exchange (ETDEWEB)

    O' Donnell, Edward [U.S. Nuclear Regulatory Commission, Washington, DC (United States); Ridky, Robert W [University of Maryland, College Park, MD (United States); Schulz, Robert K [University of California, Berkeley, CA (United States)

    1992-07-01

    The study's objective is to assess means for controlling water infiltration through waste disposal unit covers in humid regions. Experimental work is being performed in large-scale lysimeters (75x45x10') at Beltsville, MD, and results of the assessment are applicable to disposal of low-level radioactive waste (LLW), uranium mill tailings, hazardous waste, and sanitary landfills. Three kinds of waste disposal unit covers or barriers to water infiltration are being investigated. They are: 1) resistive layer barrier, 2) conductive layer barrier, and 3) bioengineering management. The resistive layer barrier consists of compacted earthen material (e.g., clay). The conductive layer barrier consists of a conductive layer in conjunction with a capillary break. As long as unsaturated flow conditions are maintained, the conductive layer will wick water around the capillary break. Below-grade layered covers such as (1) and (2) will fail if there is appreciable subsidence of the cover. Remedial action for this kind of failure will be difficult. A surface cover, called bioengineering management, is meant to overcome this problem. The bioengineering management surface barrier is easily repairable if damaged by subsidence; therefore, it could be the system of choice under active subsidence conditions. The bioengineering management procedure also has been shown to be effective in dewatering saturated trenches and could be used for remedial action efforts. After cessation of subsidence, that procedure could be replaced by a resistive layer barrier, or perhaps even better, a resistive layer barrier/conductive layer barrier system. This latter system would then give long-term effective protection against water entry into waste and without institutional care. As mentioned in the preceding paragraph, a bioengineering management cover might well be the cover of choice during tho active subsidence phase of a waste disposal unit. Some maintenance is required during that period. Final

  7. Control of water infiltration into near surface LLW disposal units - Progress report on field experiments at a humid region site, Beltsville, Maryland

    International Nuclear Information System (INIS)

    O'Donnell, Edward; Ridky, Robert W.; Schulz, Robert K.

    1992-01-01

    The study's objective is to assess means for controlling water infiltration through waste disposal unit covers in humid regions. Experimental work is being performed in large-scale lysimeters (75x45x10') at Beltsville, MD, and results of the assessment are applicable to disposal of low-level radioactive waste (LLW), uranium mill tailings, hazardous waste, and sanitary landfills. Three kinds of waste disposal unit covers or barriers to water infiltration are being investigated. They are: 1) resistive layer barrier, 2) conductive layer barrier, and 3) bioengineering management. The resistive layer barrier consists of compacted earthen material (e.g., clay). The conductive layer barrier consists of a conductive layer in conjunction with a capillary break. As long as unsaturated flow conditions are maintained, the conductive layer will wick water around the capillary break. Below-grade layered covers such as (1) and (2) will fail if there is appreciable subsidence of the cover. Remedial action for this kind of failure will be difficult. A surface cover, called bioengineering management, is meant to overcome this problem. The bioengineering management surface barrier is easily repairable if damaged by subsidence; therefore, it could be the system of choice under active subsidence conditions. The bioengineering management procedure also has been shown to be effective in dewatering saturated trenches and could be used for remedial action efforts. After cessation of subsidence, that procedure could be replaced by a resistive layer barrier, or perhaps even better, a resistive layer barrier/conductive layer barrier system. This latter system would then give long-term effective protection against water entry into waste and without institutional care. As mentioned in the preceding paragraph, a bioengineering management cover might well be the cover of choice during tho active subsidence phase of a waste disposal unit. Some maintenance is required during that period. Final

  8. Minimizing magnetic fields for precision experiments

    Energy Technology Data Exchange (ETDEWEB)

    Altarev, I.; Fierlinger, P.; Lins, T.; Marino, M. G.; Nießen, B.; Petzoldt, G.; Reisner, M.; Stuiber, S., E-mail: stefan.stuiber@ph.tum.de; Sturm, M.; Taggart Singh, J.; Taubenheim, B. [Physikdepartment, Technische Universität München, D-85748 Garching (Germany); Rohrer, H. K. [Rohrer GmbH, D-80667 München (Germany); Schläpfer, U. [IMEDCO AG, CH-4614 Hägendorf (Switzerland)

    2015-06-21

    An increasing number of measurements in fundamental and applied physics rely on magnetically shielded environments with sub nano-Tesla residual magnetic fields. State of the art magnetically shielded rooms (MSRs) consist of up to seven layers of high permeability materials in combination with highly conductive shields. Proper magnetic equilibration is crucial to obtain such low magnetic fields with small gradients in any MSR. Here, we report on a scheme to magnetically equilibrate MSRs with a 10 times reduced duration of the magnetic equilibration sequence and a significantly lower magnetic field with improved homogeneity. For the search of the neutron's electric dipole moment, our finding corresponds to a 40% improvement of the statistical reach of the measurement. However, this versatile procedure can improve the performance of any MSR for any application.

  9. Minimizing magnetic fields for precision experiments

    International Nuclear Information System (INIS)

    Altarev, I.; Fierlinger, P.; Lins, T.; Marino, M. G.; Nießen, B.; Petzoldt, G.; Reisner, M.; Stuiber, S.; Sturm, M.; Taggart Singh, J.; Taubenheim, B.; Rohrer, H. K.; Schläpfer, U.

    2015-01-01

    An increasing number of measurements in fundamental and applied physics rely on magnetically shielded environments with sub nano-Tesla residual magnetic fields. State of the art magnetically shielded rooms (MSRs) consist of up to seven layers of high permeability materials in combination with highly conductive shields. Proper magnetic equilibration is crucial to obtain such low magnetic fields with small gradients in any MSR. Here, we report on a scheme to magnetically equilibrate MSRs with a 10 times reduced duration of the magnetic equilibration sequence and a significantly lower magnetic field with improved homogeneity. For the search of the neutron's electric dipole moment, our finding corresponds to a 40% improvement of the statistical reach of the measurement. However, this versatile procedure can improve the performance of any MSR for any application

  10. A field experiment on power line stabilization by SMES system

    International Nuclear Information System (INIS)

    Irie, F.; Takeo, M.; Sato, S.; Katahira, O.; Fukui, F.; Takamatsu, M.

    1992-01-01

    In this paper field experiments on stabilization of a hydro power plant by a SMES system are reported, where a generator having a rating of 60 kW at 3.3kV is connected to a 6.6kV power distribution line. The SMES system is composed of two 30kVA GTO convertors and a superconducting magnet system with an energy of 30kJ at 100A. Experiments of stabilization for the generator fluctuation caused by a sudden insertion of inductors in the line are successfully performed for some control modes. The value of the SMES system to compensate for a short period voltage dip is also confirmed

  11. Field experiment with liquid manure and enhanced biochar

    Science.gov (United States)

    Dunst, Gerald

    2017-04-01

    Field experiments with low amounts of various liquid manure enhanced biochars. In 2016 a new machine was developed to inject liquid biochar based fertilizer directly into the crop root zone. A large-scale field experiment with corn and oil seed pumpkin was set-up on 42 hectares on 15 different fields in the south East of Austria. Three treatments were compared: (1) surface spreading of liquid manure as control (common practice), (2) 20 cm deep root zone injection with same amount of liquid manure, and (3) 20 cm deep root zone injection with same amount of liquid manure mixed with 1 to 2 tons of various nutrient enhanced biochars. The biochar were quenched with the liquid phase from a separated digestate from a biogas plant (feedstock: cow manure). From May to October nitrate and ammonium content was analyzed monthly from 0-30cm and 30-60cm soil horizons. At the end of the growing season the yield was determined. The root zone injection of the liquid manure reduced the nitrate content during the first two months at 13-16% compared to the control. When the liquid manure was blended with biochar, Nitrate soil content was lowest (reduction 40-47%). On average the root zone injection of manure-biochar increased the yield by 7% compared to the surface applied control and 3% compared to the root zone injected manure without biochar. The results shows, that biochar is able to reduce the Nitrate load in soils and increase the yield of corn at the same time. The nutrient efficiency of organic liquid fertilizers can be increased.

  12. Field experiment on multicomponent ion exchange in a sandy aquifer

    International Nuclear Information System (INIS)

    Bjerg, P.L.; Christensen, T.H.

    1990-01-01

    A field experiment is performed in a sandy aquifer in order to study ion exchange processes and multicomponent solute transport modeling. An injection of groundwater spiked with sodium and potassium chloride was performed over a continuous period of 37 days. The plume is monitored by sampling 350 filters in a spatial grid. The sampling aims at establishing compound (calcium, magnesium, potassium, sodium, chloride) breakthrough curves at various filters 15 to 100 m from the point of injection and areal distribution maps at various cross sections from 0 to 200 m from the point of injection. A three-dimensional multicomponent solute transport model will be used to model the field experiments. The chemical model includes cation exchange, precipitation, dissolution, complexation, ionic strength and the carbonate system. Preliminary results from plume monitoring show that the plume migration is relatively well controlled considering the scale and conditions of the experiment. The transverse dispersion is small causing less dilution than expected. The ion exchange processes have an important influence on the plume composition. Retardation of the injected ions is substantial, especially for potassium. Calcium exhibits a substantial peak following chloride due to release from the ion exchange sites on the sediment. (Author) (8 refs., 5 figs., tab.)

  13. Solar field control for desalination plants

    Energy Technology Data Exchange (ETDEWEB)

    Roca, Lidia [Convenio Universidad de Almeria, Plataforma Solar de Almeria, Ctra. Senes s/n, 04200 Tabernas, Almeria (Spain); Berenguel, Manuel [Universidad de Almeria, Dpto. Lenguajes y Computacion, Ctra. Sacramento s/n, 04120 Almeria (Spain); Yebra, Luis; Alarcon-Padilla, Diego C. [CIEMAT, Plataforma Solar de Almeria, Ctra. Senes s/n, 04200 Tabernas, Almeria (Spain)

    2008-09-15

    This paper presents the development and application of a feedback linearization control strategy for a solar collector field supplying process heat to a multi-effect seawater distillation plant. Since one objective is to use as much as possible the solar resource, control techniques can be used to produce the maximum heat process in the solar field. The main purpose of the controller presented in this paper is to manipulate the water flow rate to maintain an outlet-inlet temperature gradient in the collectors, thereby ensuring continuous process heating, or in other words, continuous production of fresh water in spite of disturbances. The dynamic behaviour of this solar field was approximated by a simplified lumped-parameters nonlinear model based on differential equations, validated with real data and used in the feedback linearization control design. Experimental results in the seawater desalination plant at the Plataforma Solar de Almeria (Spain) show good agreement of the model and real data despite the approximations included. Moreover, by using feedback linearization control it is possible to track a constant gradient temperature reference in the solar field with good results. (author)

  14. Viscosity Control Experiment Feasibility Study

    Energy Technology Data Exchange (ETDEWEB)

    Morris, Heidi E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bradley, Paul Andrew [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2018-01-31

    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 modify 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.

  15. Entrepreneurship, teams and sustainability: A series of field experiments

    NARCIS (Netherlands)

    Rosendahl Huber, L.

    2015-01-01

    This dissertation reports the results from three field experiments that were conducted within the setting of one of the leading, internationally renowned entrepreneurship education programs for primary schools called BizWorld. The first field experiment evaluates the program’s effectiveness in terms

  16. Analysis of ARAC participation in the Idaho field experiment

    International Nuclear Information System (INIS)

    Rosen, L.C.; Hill, K.L.

    1986-02-01

    The 1981 Idaho Field Experiment to coordinate data sets and evaluate model and computer facilities is summarized herein. Participation of the Atmospheric Release Advisory Capability (ARAC) of the Lawrence Livermore National Laboratory in the field experiment is discussed. The computed ARAC results are compared with the observational data sets and analyzed. 12 refs., 44 figs., 3 tabs

  17. Tandem mirror and field-reversed mirror experiments

    Energy Technology Data Exchange (ETDEWEB)

    Coensgen, F.H.; Simonen, T.C.; Turner, W.C.

    1979-08-21

    This paper is largely devoted to tandem mirror and field-reversed mirror experiments at the Lawrence Livermore Laboratory (LLL), and briefly summarizes results of experiments in which field-reversal has been achieved. In the tandem experiment, high-energy, high-density plasmas (nearly identical to 2XIIB plasmas) are located at each end of a solenoid where plasma ions are electrostatically confined by the high positive poentials arising in the end plug plasma. End plug ions are magnetically confined, and electrons are electrostatically confined by the overall positive potential of the system. The field-reversed mirror reactor consists of several small field-reversed mirror plasmas linked together for economic reasons. In the LLL Beta II experiment, generation of a field-reversed plasma ring will be investigated using a high-energy plasma gun with a transverse radial magnetic field. This plasma will be further heated and sustained by injection of intense, high-energy neutral beams.

  18. Preliminary experiments with a cusp-field ion source

    International Nuclear Information System (INIS)

    Bickes, R.W. Jr.; O'Hagan, J.B.

    1980-12-01

    Preliminary experiments with a cusp field ion source have been completed. Measurements were made of the total ion current and mass and energy distributions as a function of source operating conditions and cusp field geometry. These experiments have indicated that a cusp field source may be used in the Sandia Neutron Generator for Cancer Therapy and may permit the incorporation of a simplified unpumped accelerator design. Suggestions for future work are briefly outlined

  19. Rotor Field Oriented Control with adaptive Iron Loss Compensation

    DEFF Research Database (Denmark)

    Rasmussen, Henrik; Vadstrup, P.; Børsting, H.

    1999-01-01

    It is well known from the literature that iron loses in an induction motor implies field angle estimation errors and hence detuning problems. In this paper a new method for estimating the iron loss resistor in an induction motor is presented. The method is based on a traditional dynamic model...... controlled in a Field Oriented Control scheme. This deviation is used to force a MIT-rule based adaptive estimator. An adaptive compensator containing the developed estimator is introduced and verified by simulations and tested by real time experiments....

  20. Engineering-scale dust control experiments

    International Nuclear Information System (INIS)

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

    1990-12-01

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

  1. Classroom and Field Experiments for Florida's Environmental Resources.

    Science.gov (United States)

    Lewis, Jim

    This booklet is intended to help teachers in Florida manage the growing interest in environmental education. Fourteen experiments are grouped into the environmental areas of the water cycle, groundwater, water pollution, waste and water treatment, air pollution, and field experiments. Experiments include demonstrations of the water cycle, the…

  2. Control of neutron spectrometry experiments using minicomputers

    International Nuclear Information System (INIS)

    Uberschlag, Jacques.

    1977-01-01

    Some neutron spectrometers at EL3 were equipped with self-contained minicomputer control devices; the H11 experiment has been on operation since june 1976, the H5A and H9V experiments are presently in course of ultimate testing. The diagram shows the general organization of all the experiments. The special characteristics of each experiment are briefly outlined together with some technical aspects of the software (equipment interfaces, means for the physicist to intervene) [fr

  3. Arctic Observing Experiment (AOX) Field Campaign Report

    Energy Technology Data Exchange (ETDEWEB)

    Rigor, Ignatius [Applied Physics Lab, University of Washington; Johnson, Jim [Applied Physics Lab, University of Washington; Motz, Emily [National Ice Center; Bisic, Aaron [National Ice Center

    2017-06-30

    Our ability to understand and predict weather and climate requires an accurate observing network. One of the pillars of this network is the observation of the fundamental meteorological parameters: temperature, air pressure, and wind. We plan to assess our ability to measure these parameters for the polar regions during the Arctic Observing Experiment (AOX, Figure 1) to support the International Arctic Buoy Programme (IABP), Arctic Observing Network (AON), International Program for Antarctic Buoys (IPAB), and Southern Ocean Observing System (SOOS). Accurate temperature measurements are also necessary to validate and improve satellite measurements of surface temperature across the Arctic. Support for research associated with the campaign is provided by the National Science Foundation, and by other US agencies contributing to the US Interagency Arctic Buoy Program. In addition to the support provided by the U.S Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility’s North Slope of Alaska (NSA) site at Barrow and the National Science Foundation (NSF), the U.S. IABP is supported by the U.S. Coast Guard (USCG), the National Aeronautics and Space Administration (NASA), the National Ice Center (NIC), the National Oceanic and Atmospheric Administration (NOAA), and the Office of Naval Research (ONR).

  4. A Multiposture Locomotor Training Device with Force-Field Control

    Directory of Open Access Journals (Sweden)

    Jianfeng Sui

    2014-11-01

    Full Text Available This paper introduces a multiposture locomotor training device (MPLTD with a closed-loop control scheme based on joint angle feedback, which is able to overcome various difficulties resulting from mechanical vibration and the weight of trainer to achieve higher accuracy trajectory. By introducing the force-field control scheme used in the closed-loop control, the device can obtain the active-constrained mode including the passive one. The MPLTD is mainly composed of three systems: posture adjusting and weight support system, lower limb exoskeleton system, and control system, of which the lower limb exoskeleton system mainly includes the indifferent equilibrium mechanism with two degrees of freedom (DOF and the driving torque is calculated by the Lagrangian function. In addition, a series of experiments, the weight support and the trajectory accuracy experiment, demonstrate a good performance of mechanical structure and the closed-loop control.

  5. Microcontroller-based Feedback Control Laboratory Experiments

    Directory of Open Access Journals (Sweden)

    Chiu Choi

    2014-06-01

    Full Text Available this paper is a result of the implementation of the recommendations on enhancing hands-on experience of control engineering education using single chip, small scale computers such as microcontrollers. A set of microcontroller-based feedback control experiments was developed for the Electrical Engineering curriculum at the University of North Florida. These experiments provided hands-on techniques that students can utilize in the development of complete solutions for a number of servo control problems. Significant effort was devoted to software development of feedback controllers and the associated signal conditioning circuits interfacing between the microcontroller and the physical plant. These experiments have stimulated the interest of our students in control engineering.

  6. Field experiments of Anopheles gambiae attraction to local fruits/seedpods and flowering plants in Mali to optimize strategies for malaria vector control in Africa using attractive toxic sugar bait methods

    Directory of Open Access Journals (Sweden)

    Bah Sekou

    2010-09-01

    Full Text Available Abstract Background Based on recent studies in Israel demonstrating that attractive toxic sugar bait (ATSB methods can be used to decimate local anopheline and culicine mosquito populations, an important consideration is whether the same methods can be adapted and improved to attract and kill malaria vectors in Africa. The ATSB approach uses fruit or flower scent as an attractant, sugar solution as a feeding stimulant, and an oral toxin. The ATSB solutions are either sprayed on vegetation or suspended in simple bait stations, and the mosquitoes ingesting the toxic solutions are killed. As such, this approach targets sugar-feeding female and male mosquitoes. This study examines the attractiveness of African malaria vectors to local fruits/seedpods and flowering plants, key biological elements of the ATSB approach for mosquito control. Methods Three field experiments were conducted at sites in Mali. The attraction of Anopheles gambiae s.l. to 26 different local fruits and seedpods was determined at a site in the semi-arid Bandiagara District of Mali. Wire mesh glue traps with fruits/seedpods suspended on skewers inside were set along a seasonal lagoon. Seven replicates of each fruit/seedpod species were tested, with a water-soaked sponge and a sugar-soaked sponge as controls. The attraction of An. gambiae s.l. to 26 different types of flowering plants was determined at a site near Mopti in Mali. The flowering plants held in a water-filled buried container were tested using the same glue traps, with controls including water only and sugar solution. Six replicates of each selected plant type were tested on transects between rice paddies. Additional studies using CDC light traps were done to determine the relative densities and periodicity of An. gambiae s.l. attraction to branches of the most highly attractive flowering plant, branches without flowers, human odor, and candescent light. Results Of the 26 fruits and seedpods tested, 6 were attractive

  7. Field experiments of Anopheles gambiae attraction to local fruits/seedpods and flowering plants in Mali to optimize strategies for malaria vector control in Africa using attractive toxic sugar bait methods.

    Science.gov (United States)

    Müller, Günter C; Beier, John C; Traore, Sekou F; Toure, Mahamoudou B; Traore, Mohamed M; Bah, Sekou; Doumbia, Seydou; Schlein, Yosef

    2010-09-20

    Based on recent studies in Israel demonstrating that attractive toxic sugar bait (ATSB) methods can be used to decimate local anopheline and culicine mosquito populations, an important consideration is whether the same methods can be adapted and improved to attract and kill malaria vectors in Africa. The ATSB approach uses fruit or flower scent as an attractant, sugar solution as a feeding stimulant, and an oral toxin. The ATSB solutions are either sprayed on vegetation or suspended in simple bait stations, and the mosquitoes ingesting the toxic solutions are killed. As such, this approach targets sugar-feeding female and male mosquitoes. This study examines the attractiveness of African malaria vectors to local fruits/seedpods and flowering plants, key biological elements of the ATSB approach for mosquito control. Three field experiments were conducted at sites in Mali. The attraction of Anopheles gambiae s.l. to 26 different local fruits and seedpods was determined at a site in the semi-arid Bandiagara District of Mali. Wire mesh glue traps with fruits/seedpods suspended on skewers inside were set along a seasonal lagoon. Seven replicates of each fruit/seedpod species were tested, with a water-soaked sponge and a sugar-soaked sponge as controls. The attraction of An. gambiae s.l. to 26 different types of flowering plants was determined at a site near Mopti in Mali. The flowering plants held in a water-filled buried container were tested using the same glue traps, with controls including water only and sugar solution. Six replicates of each selected plant type were tested on transects between rice paddies. Additional studies using CDC light traps were done to determine the relative densities and periodicity of An. gambiae s.l. attraction to branches of the most highly attractive flowering plant, branches without flowers, human odor, and candescent light. Of the 26 fruits and seedpods tested, 6 were attractive to An. gambiae s.l. females and males, respectively

  8. Magnetic field saturation in the Riga dynamo experiment.

    Science.gov (United States)

    Gailitis, A; Lielausis, O; Platacis, E; Dement'ev, S; Cifersons, A; Gerbeth, G; Gundrum, T; Stefani, F; Christen, M; Will, G

    2001-04-02

    After the dynamo experiment in November 1999 [A. Gailitis et al., Phys. Rev. Lett. 84, 4365 (2000)] had shown magnetic field self-excitation in a spiraling liquid metal flow, in a second series of experiments emphasis was placed on the magnetic field saturation regime as the next principal step in the dynamo process. The dependence of the strength of the magnetic field on the rotation rate is studied. Various features of the saturated magnetic field are outlined and possible saturation mechanisms are discussed.

  9. Controlling Casimir force via coherent driving field

    Science.gov (United States)

    Ahmad, Rashid; Abbas, Muqaddar; Ahmad, Iftikhar; Qamar, Sajid

    2016-04-01

    A four level atom-field configuration is used to investigate the coherent control of Casimir force between two identical plates made up of chiral atomic media and separated by vacuum of width d. The electromagnetic chirality-induced negative refraction is obtained via atomic coherence. The behavior of Casimir force is investigated using Casimir-Lifshitz formula. It is noticed that Casimir force can be switched from repulsive to attractive and vice versa via coherent control of the driving field. This switching feature provides new possibilities of using the repulsive Casimir force in the development of new emerging technologies, such as, micro-electro-mechanical and nano-electro-mechanical systems, i.e., MEMS and NEMS, respectively.

  10. Proton and deuterium NMR experiments in zero field

    International Nuclear Information System (INIS)

    Millar, J.M.

    1986-02-01

    High field solid-state NMR lineshapes suffer from inhomogeneous broadening since resonance frequencies are a function of molecular orientation. Time domain zero field NMR is a two-dimensional field-cycling technique which removes this broadening by probing the evolution of the spin system under zero applied field. The simplest version, the sudden transition experiment, induces zero field evolution by the sudden removal of the applied magnetic field. Theory and experimental results of this experiment and several variations using pulsed dc magnetic fuelds to initiate zero field evolution are presented. In particular, the pulsed indirect detection method allows detection of the zero field spectrum of one nuclear spin species via another (usually protons) by utilizing the level crossings which occur upon adiabatic demagnetization to zero field. Experimental examples of proton/deuteron systems are presented which demonstrate the method results in enhanced sensitivity relative to that obtained in sudden transition experiments performed directly on deuterium. High resolution 2 H NQR spectra of a series of benzoic acid derivatives are obtained using the sudden transition and indirect detection methods. Librational oscillations in the water molecules of barium chlorate monohydrate are studied using proton and deuterium ZF experiments. 177 refs., 88 figs., 2 tabs

  11. Hierarchical Control of the ATLAS Experiment

    CERN Document Server

    Barriuso-Poy, Alex; Llobet-Valero, E

    2007-01-01

    Control systems at High Energy Physics (HEP) experiments are becoming increasingly complex mainly due to the size, complexity and data volume associated to the front-end instrumentation. In particular, this becomes visible for the ATLAS experiment at the LHC accelerator at CERN. ATLAS will be the largest particle detector ever built, result of an international collaboration of more than 150 institutes. The experiment is composed of 9 different specialized sub-detectors that perform different tasks and have different requirements for operation. The system in charge of the safe and coherent operation of the whole experiment is called Detector Control System (DCS). This thesis presents the integration of the ATLAS DCS into a global control tree following the natural segmentation of the experiment into sub-detectors and smaller sub-systems. The integration of the many different systems composing the DCS includes issues such as: back-end organization, process model identification, fault detection, synchronization ...

  12. Attention discrimination: theory and field experiments with monitoring information acquisition

    Czech Academy of Sciences Publication Activity Database

    Bartoš, Vojtěch; Bauer, Michal; Chytilová, Julie; Matějka, Filip

    2016-01-01

    Roč. 106, č. 6 (2016), s. 1437-1475 ISSN 0002-8282 Institutional support: RVO:67985998 Keywords : inattention * discrimination * field experiment Subject RIV: AH - Economics Impact factor: 4.026, year: 2016

  13. A new controller for the JET error field correction coils

    International Nuclear Information System (INIS)

    Zanotto, L.; Sartori, F.; Bigi, M.; Piccolo, F.; De Benedetti, M.

    2005-01-01

    This paper describes the hardware and the software structure of a new controller for the JET error field correction coils (EFCC) system, a set of ex-vessel coils that recently replaced the internal saddle coils. The EFCC controller has been developed on a conventional VME hardware platform using a new software framework, recently designed for real-time applications at JET, and replaces the old disruption feedback controller increasing the flexibility and the optimization of the system. The use of conventional hardware has required a particular effort in designing the software part in order to meet the specifications. The peculiarities of the new controller will be highlighted, such as its very useful trigger logic interface, which allows in principle exploring various error field experiment scenarios

  14. Underactuated ship tracking control : theory and experiments

    NARCIS (Netherlands)

    Pettersen, K.Y.; Nijmeijer, H.

    2001-01-01

    We consider complete state tracking feedback control of a ship having two controls, namely surge force and yaw moment. The ship model has similarities with chained form systems but cannot directly be transformed in chained form. In particular, the model has a drift vector field as opposed to the

  15. ASSISTments Dataset from Multiple Randomized Controlled Experiments

    Science.gov (United States)

    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.…

  16. Incentives versus sorting in tournaments: evidence from a field experiment

    NARCIS (Netherlands)

    Leuven, E.; Oosterbeek, H.; Sonnemans, J.; van der Klaauw, B.

    2011-01-01

    Existing field evidence on rank-order tournaments typically does not allow disentangling incentive and sorting effects. We conduct a field experiment illustrating the confounding effect. Students in an introductory microeconomics course selected themselves into tournaments with low, medium, or high

  17. Superparamagnetic beads in rotating magnetic fields: microfluidic experiments

    NARCIS (Netherlands)

    Den Toonder, J.M.J.; Bokdam, M.

    2008-01-01

    The effect of the Mason number, ratio of viscous and magnetic force, on suspended superparamagnetic micro sized beads was investigated experimentally. Microfluidic experiments were performed in a set-up that generates a rotating homogeneous magnetic field. In the presence of a magnetic field, the

  18. Interactivity in automatic control: foundations and experiences

    OpenAIRE

    Dormido Bencomo, Sebastián; Guzmán Sánchez, José Luis; Costa Castelló, Ramon; Berenguel, M

    2012-01-01

    The first part of this paper presents the concepts of interactivity and visualization and its essential role in learning the fundamentals and techniques of automatic control. More than 10 years experience of the authors in the development and design of interactive tools dedicated to the study of automatic control concepts are also exposed. The second part of the paper summarizes the main features of the “Automatic Control with Interactive Tools” text that has been recently published by Pea...

  19. Operational experience gained from the Central Brae subsea field

    International Nuclear Information System (INIS)

    Sapp, S.J.; Gomersall, S.D.

    1994-01-01

    The size of the field discoveries made in the North Sea in recent years has declined dramatically. With the low oil price many small fields are not viable stand alone developments. The North Sea has a large, well developed infrastructure of production facilities and pipelines. With many platforms now operating below optimum production rate, subsea tieback of these small fields utilizing the available processing capacity is the most economically attractive means of development. This paper presents a history of such a field development. The Central Brae field is located within the Brae complex of fields, 155 miles north east of Aberdeen, and has been developed by means of a subsea facility tied back to the Brae Alpha platform. A great deal of experience has been gained through the field development, not only in subsea operations but also in completion and template design and operating philosophy

  20. South American Field Experience: An Initiative in International Education. The Implementation Journal for the South American Field Experience.

    Science.gov (United States)

    Martin, William J.

    A description is provided of Williamsport Area Community College's (WACC's) South American Field Experience program, a travel/study program for faculty and staff designed to provide a variety of learning experiences through a three week trip to Peru, Chile, Argentina, and Brazil. Chapter I presents an overview of the development of the project,…

  1. Influencing attitudes toward science through field experiences in biology

    Science.gov (United States)

    Carpenter, Deborah Mcintyre

    The purpose of this study was to determine how student attitudes toward science are influenced by field experiences in undergraduate biology courses. The study was conducted using two institutions of higher education including a 2-year lower-level and a 2-year upper-level institution. Data were collected through interviews with student participants, focus group discussions, students' journal entries, and field notes recorded by the researcher during the field activities. Photographs and video recordings were also used as documentation sources. Data were collected over a period of 34 weeks. Themes that emerged from the qualitative data included students' beliefs that field experiences (a) positively influence student motivation to learn, (b) increase student ability to learn the concepts being taught, and (c) provide opportunities for building relationships and for personal growth. The findings of the study reinforce the importance of offering field-study programs at the undergraduate level to allow undergraduate students the opportunity to experience science activities in a field setting. The research study was framed by the behavioral and developmental theories of attitude and experience including the Theory of Planned Behavior (Ajzen, 1991) and the Theory of Experiential Learning (Kolb, 1984).

  2. Grimsel Test Site: modelling radionuclide migration field experiments

    International Nuclear Information System (INIS)

    Heer, W.; Hadermann, J.

    1994-09-01

    In the migration field experiments at Nagra's Grimsel Test Site, the processes of nuclide transport through a well defined fractured shear-zone in crystalline rock are being investigated. For these experiments, model calculations have been performed to obtain indications on validity and limitation of the model applied and the data deduced under field conditions. The model consists of a hydrological part, where the dipole flow fields of the experiments are determined, and a nuclide transport part, where the flow field driven nuclide propagation through the shear-zone is calculated. In addition to the description of the model, analytical expressions are given to guide the interpretation of experimental results. From the analysis of experimental breakthrough curves for conservative uranine, weakly sorbing sodium and more stronger sorbing strontium tracers, the following main results can be derived: i) The model is able to represent the breakthrough curves of the migration field experiments to a high degree of accuracy, ii) The process of matrix diffusion is manifest through the tails of the breakthrough curves decreasing with time as t -3/2 and through the special shape of the tail ends, both confirmed by the experiments, iii) For nuclide sorbing rapidly, not too strongly, linearly, and exhibiting a reversible cation exchange process on fault gouge, the laboratory sorption coefficient can reasonably well be extrapolated to field conditions. Adequate care in selecting and preparing the rock samples is, of course, a necessary requirement. Using the parameters determined in the previous analysis, predictions are made for experiments in a smaller an faster flow field. For conservative uranine and weakly sorbing sodium, the agreement of predicted and measured breakthrough curves is good, for the more stronger sorbing strontium reasonable, confirming that the model describes the main nuclide transport processes adequately. (author) figs., tabs., 29 refs

  3. The Detector Control of the PANDA Experiment

    International Nuclear Information System (INIS)

    Feldbauer, F

    2014-01-01

    The PANDA experiment will be built at the antiproton storage ring HESR, a part of the new accelerator facility FAIR in Darmstadt, Germany. PANDA aims amongst other topics for high precision measurements in hadron spectroscopy and search for exotic matter. To guarantee the high resolution of the different components a detector control system (DCS) monitoring temperatures, humidity, pressure, and controlling chillers and power supplies is needed. The DCS of PANDA is built using the open-source software package EPICS (Experimental Physics and Industrial Control System) with a PANDA specific version of Control-System Studio. In this document the general concepts of the PANDA DCS will be discussed

  4. DABASCO Experiment Data Acquisition and Control System

    International Nuclear Information System (INIS)

    Alberdi Primicia, J.; Artigao Arteaga, A.; Barcala Rieveira, J. M.; Oller Gonzalez, J. C.

    2000-01-01

    DABASCO experiment wants to study the thermohydraulic phenomena produced into the containment area for a severe accident in a nuclear power facility. This document describes the characteristics of the data acquisition and control system used in the experiment. The main elements of the system were a data acquisition board, PCI-MIO-16E-4, and an application written with LaB View. (Author) 5 refs

  5. Optimal control of quantum systems: Origins of inherent robustness to control field fluctuations

    International Nuclear Information System (INIS)

    Rabitz, Herschel

    2002-01-01

    The impact of control field fluctuations on the optimal manipulation of quantum dynamics phenomena is investigated. The quantum system is driven by an optimal control field, with the physical focus on the evolving expectation value of an observable operator. A relationship is shown to exist between the system dynamics and the control field fluctuations, wherein the process of seeking optimal performance assures an inherent degree of system robustness to such fluctuations. The presence of significant field fluctuations breaks down the evolution of the observable expectation value into a sequence of partially coherent robust steps. Robustness occurs because the optimization process reduces sensitivity to noise-driven quantum system fluctuations by taking advantage of the observable expectation value being bilinear in the evolution operator and its adjoint. The consequences of this inherent robustness are discussed in the light of recent experiments and numerical simulations on the optimal control of quantum phenomena. The analysis in this paper bodes well for the future success of closed-loop quantum optimal control experiments, even in the presence of reasonable levels of field fluctuations

  6. Hardware controls for the STAR experiment at RHIC

    International Nuclear Information System (INIS)

    Reichhold, D.; Bieser, F.; Bordua, M.; Cherney, M.; Chrin, J.; Dunlop, J.C.; Ferguson, M.I.; Ghazikhanian, V.; Gross, J.; Harper, G.; Howe, M.; Jacobson, S.; Klein, S.R.; Kravtsov, P.; Lewis, S.; Lin, J.; Lionberger, C.; LoCurto, G.; McParland, C.; McShane, T.; Meier, J.; Sakrejda, I.; Sandler, Z.; Schambach, J.; Shi, Y.; Willson, R.; Yamamoto, E.; Zhang, W.

    2003-01-01

    The STAR detector sits in a high radiation area when operating normally; therefore it was necessary to develop a robust system to remotely control all hardware. The STAR hardware controls system monitors and controls approximately 14,000 parameters in the STAR detector. Voltages, currents, temperatures, and other parameters are monitored. Effort has been minimized by the adoption of experiment-wide standards and the use of pre-packaged software tools. The system is based on the Experimental Physics and Industrial Control System (EPICS) . VME processors communicate with subsystem-based sensors over a variety of field busses, with High-level Data Link Control (HDLC) being the most prevalent. Other features of the system include interfaces to accelerator and magnet control systems, a web-based archiver, and C++-based communication between STAR online, run control and hardware controls and their associated databases. The system has been designed for easy expansion as new detector elements are installed in STAR

  7. The Global Control of the Virgo experiment

    International Nuclear Information System (INIS)

    Arnaud, Nicolas; Arnault, Christian; Barsuglia, Matteo; Bizouard, Marie-Anne; Brisson, Violette; Cavalier, Fabien; Chiche, Ronic; Davier, Michel; Eder, Claude; Hello, Patrice; Heusse, Philippe; Kreckelbergh, Stephane; Mansoux, Bruno

    2005-01-01

    In order to detect gravitational waves, the kilometric interferometer Virgo needs an active control of the positions of the suspended optical components, keeping the detector at its working point. The constraints are about 10 -10 m RMS for the longitudinal control ('Locking') and 10 -9 rad RMS for the angular degrees of freedom ('Alignment'). A dedicated hardware and software named Global Control is in charge of the Locking and the Alignment loops for the Virgo experiment. This system has been designed to match the synchronization constraint and provide a flexible tool in order to easily integrate the various algorithms needed for the control of Virgo. This paper presents the technical requirements to be fulfilled by the Global Control. Then, the dedicated hardware is described and the overall architecture of the Global Control is shown

  8. The Global Control of the Virgo experiment

    Energy Technology Data Exchange (ETDEWEB)

    Arnaud, Nicolas [Laboratoire de l' Accelerateur Lineaire, CNRS-IN2P3 and Universite Paris Sud, Ba-hat timent 200, Campus d' Orsay, B.P. 34, 91898 Orsay Cedex (France); Arnault, Christian [Laboratoire de l' Accelerateur Lineaire, CNRS-IN2P3 and Universite Paris Sud, Ba-hat timent 200, Campus d' Orsay, B.P. 34, 91898 Orsay Cedex (France); Barsuglia, Matteo [Laboratoire de l' Accelerateur Lineaire, CNRS-IN2P3 and Universite Paris Sud, Ba-hat timent 200, Campus d' Orsay, B.P. 34, 91898 Orsay Cedex (France); Bizouard, Marie-Anne [Laboratoire de l' Accelerateur Lineaire, CNRS-IN2P3 and Universite Paris Sud, Ba-hat timent 200, Campus d' Orsay, B.P. 34, 91898 Orsay Cedex (France); Brisson, Violette [Laboratoire de l' Accelerateur Lineaire, CNRS-IN2P3 and Universite Paris Sud, Ba-hat timent 200, Campus d' Orsay, B.P. 34, 91898 Orsay Cedex (France); Cavalier, Fabien [Laboratoire de l' Accelerateur Lineaire, CNRS-IN2P3 and Universite Paris Sud, Ba-hat timent 200, Campus d' Orsay, B.P. 34, 91898 Orsay Cedex (France)]. E-mail: cavalier@lal.in2p3.fr; Chiche, Ronic [Laboratoire de l' Accelerateur Lineaire, CNRS-IN2P3 and Universite Paris Sud, Ba-hat timent 200, Campus d' Orsay, B.P. 34, 91898 Orsay Cedex (France); Davier, Michel [Laboratoire de l' Accelerateur Lineaire, CNRS-IN2P3 and Universite Paris Sud, Ba-hat timent 200, Campus d' Orsay, B.P. 34, 91898 Orsay Cedex (France); Eder, Claude [Laboratoire de l' Accelerateur Lineaire, CNRS-IN2P3 and Universite Paris Sud, Ba-hat timent 200, Campus d' Orsay, B.P. 34, 91898 Orsay Cedex (France); Hello, Patrice [Laboratoire de l' Accelerateur Lineaire, CNRS-IN2P3 and Universite Paris Sud, Ba-hat timent 200, Campus d' Orsay, B.P. 34, 91898 Orsay Cedex (France); Heusse, Philippe; Kreckelbergh, Stephane; Mansoux, Bruno [Laboratoire de l' Accelerateur Lineaire, CNRS-IN2P3 and Universite Paris Sud, Ba-hat timent 200, Campus d' Orsay, B.P. 34, 91898 Orsay Cedex (France)

    2005-09-11

    In order to detect gravitational waves, the kilometric interferometer Virgo needs an active control of the positions of the suspended optical components, keeping the detector at its working point. The constraints are about 10{sup -10}m RMS for the longitudinal control ('Locking') and 10{sup -9}rad RMS for the angular degrees of freedom ('Alignment'). A dedicated hardware and software named Global Control is in charge of the Locking and the Alignment loops for the Virgo experiment. This system has been designed to match the synchronization constraint and provide a flexible tool in order to easily integrate the various algorithms needed for the control of Virgo. This paper presents the technical requirements to be fulfilled by the Global Control. Then, the dedicated hardware is described and the overall architecture of the Global Control is shown.

  9. Experiments on plasma turbulence induced by strong, steady electric fields

    International Nuclear Information System (INIS)

    Hamberger, S.M.

    1975-01-01

    The author discusses the effect of applying a strong electric field to collisionless plasma. In particular are compared what some ideas and prejudices lead one to expect to happen, what computer simulation experiments tell one ought to happen, and what actually does happen in two laboratory experiments which have been designed to allow the relevant instability and turbulent processes to occur unobstructed and which have been studied in sufficient detail. (Auth.)

  10. The large-s field-reversed configuration experiment

    International Nuclear Information System (INIS)

    Hoffman, A.L.; Carey, L.N.; Crawford, E.A.; Harding, D.G.; DeHart, T.E.; McDonald, K.F.; McNeil, J.L.; Milroy, R.D.; Slough, J.T.; Maqueda, R.; Wurden, G.A.

    1993-01-01

    The Large-s Experiment (LSX) was built to study the formation and equilibrium properties of field-reversed configurations (FRCs) as the scale size increases. The dynamic, field-reversed theta-pinch method of FRC creation produces axial and azimuthal deformations and makes formation difficult, especially in large devices with large s (number of internal gyroradii) where it is difficult to achieve initial plasma uniformity. However, with the proper technique, these formation distortions can be minimized and are then observed to decay with time. This suggests that the basic stability and robustness of FRCs formed, and in some cases translated, in smaller devices may also characterize larger FRCs. Elaborate formation controls were included on LSX to provide the initial uniformity and symmetry necessary to minimize formation disturbances, and stable FRCs could be formed up to the design goal of s = 8. For x ≤ 4, the formation distortions decayed away completely, resulting in symmetric equilibrium FRCs with record confinement times up to 0.5 ms, agreeing with previous empirical scaling laws (τ∝sR). Above s = 4, reasonably long-lived (up to 0.3 ms) configurations could still be formed, but the initial formation distortions were so large that they never completely decayed away, and the equilibrium confinement was degraded from the empirical expectations. The LSX was only operational for 1 yr, and it is not known whether s = 4 represents a fundamental limit for good confinement in simple (no ion beam stabilization) FRCs or whether it simply reflects a limit of present formation technology. Ideally, s could be increased through flux buildup from neutral beams. Since the addition of kinetic or beam ions will probably be desirable for heating, sustainment, and further stabilization of magnetohydrodynamic modes at reactor-level s values, neutral beam injection is the next logical step in FRC development. 24 refs., 21 figs., 2 tabs

  11. Magnetic field control of fluorescent polymer nanorods

    International Nuclear Information System (INIS)

    Kim, Taehyung; He, Le; Bardeen, Christopher J; Morales, Jason R; Beyermann, W P

    2011-01-01

    Nanoscale objects that combine high luminescence output with a magnetic response may be useful for probing local environments or manipulating objects on small scales. Ideally, these two properties would not interfere with each other. In this paper, we show that a fluorescent polymer host material can be doped with high concentrations of 20–30 nm diameter magnetic γ-Fe 2 O 3 particles and then formed into 200 nm diameter nanorods using porous anodic alumina oxide templates. Two different polymer hosts are used: the conjugated polymer polydioctylfluorene and also polystyrene doped with the fluorescent dye Lumogen Red. Fluorescence decay measurements show that 14% by weight loading of the γ-Fe 2 O 3 nanoparticles quenches the fluorescence of the polydioctylfluorene by approximately 33%, but the polystyrene/Lumogen Red fluorescence is almost unaffected. The three-dimensional orientation of both types of nanorods can be precisely controlled by the application of a moderate strength (∼0.1 T) external field with sub-second response times. Transmission electron microscope images reveal that the nanoparticles cluster in the polymer matrix, and these clusters may serve both to prevent fluorescence quenching and to generate the magnetic moment that rotates in response to the applied magnetic field.

  12. Distributed control network for optogenetic experiments

    Science.gov (United States)

    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.

  13. Games for groundwater governance: field experiments in Andhra Pradesh, India

    Directory of Open Access Journals (Sweden)

    Ruth Meinzen-Dick

    2016-09-01

    Full Text Available Groundwater is a common-pool resource that is subject to depletion in many places around the world as a result of increased use of irrigation and water-demanding cash crops. Where state capacity to control groundwater use is limited, collective action is important to increase recharge and restrict highly water-consumptive crops. We present results of field experiments in hard rock areas of Andhra Pradesh, India, to examine factors affecting groundwater use. Two nongovernmental organizations (NGOs ran the games in communities where they were working to improve watershed and water management. Results indicate that, when the links between crop choice and groundwater depletion is made explicit, farmers can act cooperatively to address this problem. Longer NGO involvement in the villages was associated with more cooperative outcomes in the games. Individuals with more education and higher perceived community social capital played more cooperatively, but neither gender nor method of payment had a significantly effect on individual behavior. When participants could repeat the game with communication, similar crop choice patterns were observed. The games provided an entry point for discussion on the understanding of communities of the interconnectedness of groundwater use and crop choice.

  14. Micro-scale hydrological field experiments in Romania

    Directory of Open Access Journals (Sweden)

    Minea Gabriel

    2016-02-01

    Full Text Available The paper (communication presents an overview of hydrologic field experiments at micro-scale in Romania. In order to experimentally investigate micro (plot-scale hydrological impact of soil erosion, the National Institute of Hydrology and Water Management founded Voineşti Experimental Basin (VES in 1964 and the Aldeni Experimental Basins (AEB in 1984. AEB and VES are located in the Curvature Subcarpathians. Experimental plots are organized in a double systems and have an area of 80 m2 (runoff plots at AEB and 300 m2 (water balance plots at VES. Land use of plot: first plot ”grass-land” is covered with perennial grass and second plot (control consists in ”bare soil”. Over the latter one, the soil is hoeing, which results in a greater development of infiltration than in the first plot. Experimental investigations at micro-scale are aimed towards determining the parameters of the water balance equation, during natural and artificial rainfalls, researching of flows and soil erosion processes on experimental plots, extrapolating relations involving runoff coefficients from a small scale to medium scale. Nowadays, the latest evolutions in data acquisition and transmission equipment are represented by sensors (such as: sensors to determinate the soil moisture content. Exploitation and dissemination of hydrologic data is accomplished by research themes/projects, year-books of basic data and papers.

  15. Field experience in use of radiation instruments in Cirus reactor

    International Nuclear Information System (INIS)

    Ramesh, N.; Sharma, R.C.; Agarwal, S.K.; Sawant, D.K.; Yadav, R.K.B.; Prasad, S.K.

    2005-01-01

    Cirus, located at Bhabha Atomic Research Centre, is a 40 MW (Th) research reactor fuelled by natural uranium, moderated by heavy water and cooled by de-mineralized light water. Graphite is used as reflector in this reactor. The reactor, commissioned in the year 1960, was in operation with availability factor of about 70% till early nineties. There after signs of ageing started surfacing up. After ageing studies, refurbishment plan was finalized and executed during the period from 1997-2002. after successful refurbishment, the reactor is in operation at full power. A wide range of radiation instruments have been used at Cirus for online monitoring of the radiological status of various process systems and environmental releases. Also, variety of survey meters, counting systems and monitors have been used by the health physics unit of the reactor for radiation hazard control. Many of these instruments, which were originally of Canadian design, have undergone changes due to obsolescence or as part of upgradation. This paper describes the experience with the radiation instruments of Cirus, bringing out their effectiveness in meeting the design intent, difficulties faced in their field use, and modifications carried out based on the performance feed back. Also, this paper highlights the areas where further efforts are needed to develop nuclear instrumentation to further strengthen monitoring and surveillance. (author)

  16. Severe Weather Field Experience: An Undergraduate Field Course on Career Enhancement and Severe Convective Storms

    Science.gov (United States)

    Godfrey, Christopher M.; Barrett, Bradford S.; Godfrey, Elaine S.

    2011-01-01

    Undergraduate students acquire a deeper understanding of scientific principles through first-hand experience. To enhance the learning environment for atmospheric science majors, the University of North Carolina at Asheville has developed the severe weather field experience. Participants travel to Tornado Alley in the Great Plains to forecast and…

  17. Concluding from operating experience to instrumentation and control systems

    International Nuclear Information System (INIS)

    Pleger, H.; Heinsohn, H.

    1997-01-01

    Where conclusions are drawn from operating experience to instrumentation and control systems, two general statements should be made. First: There have been braekdowns, there have also been deficiencies, but in principle operating experience with the instrumentation and control systems of German nuclear power plants has been good. With respect to the debates about the use of modern digital instrumentation and control systems it is safe to say, secondly, that the instrumentation and control systems currently in use are working reliably. Hence, there is no need at present to replace existing systems for reasons of technical safety. However, that time will come. It is a good thing, therefore, that the use of modern digital instrumentation and control systems is to begin in the field of limiting devices. The operating experience which will thus be accumulated will benefit digital instrumentation and control systems in their qualification process for more demanding applications. This makes proper logging of operating experience an important function, even if it cannot be transferred in every respect. All parties involved therefore should see to it that this operating experience is collected in accordance with criteria agreed upon so as to prevent unwanted surprises later on. (orig.) [de

  18. Remote Experiments in Control Engineering Education Laboratory

    Directory of Open Access Journals (Sweden)

    Milica B Naumović

    2008-05-01

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

  19. Real-time measurement and control at Jet. Experiment Control

    International Nuclear Information System (INIS)

    Felton, R.; Zabeo, L.; Sartori, F.; Piccolo, F.; Farthing, J.; Budd, T.; Dorling, S.; McCullen, P.; Harling, J.; Dalley, S.; Goodyear, A.; Stephen, A.; Card, P.; Bright, M.; Lucock, R.; Jones, E.; Griph, S.; Hogben, C.; Beldishevski, M.; Buckley, M.; Davis, J.; Young, I.; Hemming, O.; Wheatley, M.; Heesterman, P.; Lloyd, G.; Walters, M.; Bridge, R.; Leggate, H.; Howell, D.; Zastrow, K.D.; Giroud, C.; Coffey, I.; Hawkes, N.; Stamp, M.; Barnsley, R.; Edlington, T.; Guenther, K.; Gowers, C.; Popovichef, S.; Huber, A.; Ingesson, C.; Joffrin, E.; Mazon, D.; Moreau, D.; Murari, A.; Riva, M.; Barana, O.; Bolzonella, T.; Valisa, M.; Innocente, P.; Zerbini, M.; Bosak, K.; Blum, J.; Vitale, E.; Crisanti, F.; La Luna, E. de; Sanchez, J.

    2004-01-01

    Over the past few ears, the preparation of ITER-relevant plasma scenarios has been the main focus experimental activity on tokamaks. The development of integrated, simultaneous, real-time controls of plasma shape, current, pressure, temperature, radiation, neutron profiles, and also impurities, ELMs (edge localized modes) and MHD are now seen to be essential for further development of quasi-steady state conditions with feedback, or the stabilisation of transient phenomena with event-driven actions. For this thrust, the EFDA JET Real Time Project has developed a set of real-time plasma measurements, experiment control, and communication facilities. The Plasma Diagnostics used for real-time experiments are Far Infra Red interferometry, polarimetry, visible, UV and X-ray spectroscopy, LIDAR, bolometry, neutron and magnetics. Further analysis systems produce integrated results such as temperature profiles on geometry derived from MHD equilibrium solutions. The Actuators include toroidal, poloidal and divertor coils, gas and pellet fuelling, neutral beam injection, radiofrequency (ICRH) waves and microwaves (LH). The Heating/Fuelling Operators can either define a power or gas request waveform or select the real-time instantaneous power/gas request from the Real Time Experiment Central Control (RTCC) system. The Real Time Experiment Control system provides both a high-level, control-programming environment and interlocks with the actuators. A MATLAB facility is being developed for the development of more complex controllers. The plasma measurement, controller and plant control systems communicate in ATM network. The EFDA Real Time project is essential groundwork for future reactors such as ITER. It involves many staff from several institutions. The facility is now frequently used in experiments. (authors)

  20. Luck or cheating? A field experiment on honesty with children

    NARCIS (Netherlands)

    Bucciol, A.; Piovesan, M.

    2011-01-01

    We run an experiment to study the relationship between honesty, age and self-control. We focus on children aged between 5 and 15 as the literature suggests that self-control develops within such age range. We ask each child to toss a fair coin in private and to record the outcome (white or black) on

  1. An Oceanographic Decision Support System for Scientific Field Experiments

    Science.gov (United States)

    Maughan, T.; Das, J.; McCann, M. P.; Rajan, K.

    2011-12-01

    Thom Maughan, Jnaneshwar Das, Mike McCann, Danelle Cline, Mike Godin, Fred Bahr, Kevin Gomes, Tom O'Reilly, Frederic Py, Monique Messie, John Ryan, Francisco Chavez, Jim Bellingham, Maria Fox, Kanna Rajan Monterey Bay Aquarium Research Institute Moss Lading, California, United States Many of the coastal ocean processes we wish to observe in order to characterize marine ecosystems have large spatial extant (tens of square km) and are dynamic moving kilometers in a day with biological processes spanning anywhere from minutes to days. Some like harmful algal blooms generate toxins which can significantly impact human health and coastal economies. In order to obtain a viable understanding of the biogeochemical processes which define their dynamics and ecology, it is necessary to persistently observe, track and sample within and near the dynamic fields using augmented methods of observation such as autonomous platforms like AUVs, gliders and surface craft. Field experiments to plan, execute and manage such multitude of assets are challenging. To alleviate this problem the autonomous systems group with its collaborators at MBARI and USC designed, built and fielded a prototype Oceanographic Decision Support System (ODSS) that provides situational awareness and a single portal to visualize and plan deployments for the large scale October 2010 CANON field program as well as a series of 2 week field programs in 2011. The field programs were conducted in Monterey Bay, a known 'red tide' incubator, and varied from as many as twenty autonomous platforms, four ships and 2 manned airplanes to coordinated AUV operations, drifters and a single ship. The ODSS web-based portal was used to assimilate information from a collection of sources at sea, including AUVs, moorings, radar data as well as remote sensing products generated by partner organizations to provide a synthesis of views useful to predict the movement of a chlorophyll patch in the confines of the northern Monterey Bay

  2. The LHC experiments' joint controls project (JCOP)

    International Nuclear Information System (INIS)

    Wayne Salter

    2001-01-01

    The development and maintenance of the control systems of the four Large Hadron Collider (LHC) experiments will require a non-negligible amount of resources and effort. In order to minimise the overall effort required the Joint Controls Project (JCOP) was set-up as a collaboration between CERN and the four LHC experiments to find and implement common solutions for the control of the LHC experiments. It is one of the few examples of such a wide collaboration and therefore the existence of the JCOP project is extremely significant. The author will give a brief overview of the project, its structure and its history. It will go on to summarise the various sub-projects that have been initiated under the auspices of JCOP together will their current status. It will highlight that the JCOP general principle is to promote the use of industrial solutions wherever possible. However, this does not rule out the provision of custom solutions when non-standard devices or very large numbers of devices have to be controlled. The author will also discuss the architecture foreseen by JCOP and where in this architecture the various types of solutions are expected to be used. Finally, although the selection of common industrial and custom solutions is a necessary condition for JCOP to succeed, the use of these solutions in themselves would not necessarily lead to the production of homogeneous control systems. Therefore, the author will finish with a description of the JCOP Framework, which is being developed to promote the use of these common solutions, to reduce the development effort required by the various experiment development teams and to help to build and integrate control systems which can be more easily maintained

  3. Attention discrimination: theory and field experiments with monitoring information acquisition

    Czech Academy of Sciences Publication Activity Database

    Bartoš, Vojtěch; Bauer, M.; Chytilová, J.; Matějka, Filip

    2016-01-01

    Roč. 106, č. 6 (2016), s. 1437-1475 ISSN 0002-8282 R&D Projects: GA ČR(CZ) GA14-30724S Institutional support: PRVOUK-P23 Keywords : inattention * discrimination * field experiment Subject RIV: AH - Economics Impact factor: 4.026, year: 2016

  4. Exploring International Multicultural Field Experiences in Educational Technology

    Science.gov (United States)

    Wilder, Hilary; Ferris, Sharmila Pixy; An, Heejung

    2010-01-01

    Purpose: The purpose of this paper is to explore an online field experience between technology facilitator candidates in the USA and K-12 teachers in Namibia, to improve candidates' understanding of diversity and equity issues in the successful incorporation of information and communication technologies (ICT) in teaching and learning.…

  5. British Isles Field Experience: An Initiative in International Education.

    Science.gov (United States)

    Martin, William J.

    The British Isles Field Experience (BIFE) program was initiated at Williamsport Area Community College (WACC) to provide a group of WACC faculty and staff members with individual and group activities of a personal, professional, and cultural nature in order to promote an international perspective that can be infused into student, collegiate, and…

  6. Overview of quasi single helicity experiments in reversed field pinches

    International Nuclear Information System (INIS)

    Martin, P.; Marrelli, L.; Spizzo, G.

    2003-01-01

    We report the results of an experimental and theoretical project dedicated to the study of Quasi Single Helicity Reversed Field Pinch plasmas. The project has involved several RFP devices and numerical codes. It appears that QSH spectra are a feature common to all the experiments. (author)

  7. Psychology as Field Experience: Impact on Attitudes Toward Social Interventions.

    Science.gov (United States)

    Snellman, Lynn A.; And Others

    An innovation in the teaching of undergraduate psychology courses is the implementation of a field experience that gives students the opportunity to apply newly learned skills and knowledge in a community setting. Changes in undergraduates' attitudes toward various delinquency interventions were examined as a result of participation in a…

  8. Infusing Outdoor Field Experiences into the Secondary Biology Curriculum.

    Science.gov (United States)

    Owens, Ginny

    1984-01-01

    To offer students biological field experiences, teachers should use their own basic skills, be enthusiastic motivators, participate in community programs/courses/workshops to acquire additional skills/knowledge for outdoor biological education, plan outdoor excursions with safety considerations in mind, and use available resources for classroom…

  9. Rational Ignorance in Education: A Field Experiment in Student Plagiarism

    Science.gov (United States)

    Dee, Thomas S.; Jacob, Brian A.

    2012-01-01

    Plagiarism appears to be a common problem among college students, yet there is little evidence on the effectiveness of interventions designed to minimize plagiarism. This study presents the results of a field experiment that evaluated the effects of a web-based educational tutorial in reducing plagiarism. We found that assignment to the treatment…

  10. Status of SRNL radiological field lysimeter experiment-Year 1

    Energy Technology Data Exchange (ETDEWEB)

    Kaplan, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Roberts, K. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Bagwell, L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2013-10-01

    The Savannah River National Laboratory (SRNL) Radiological Field Lysimeter Experiment is a one-of-a-kind field facility designed to study radionuclide geochemical processes at a larger spatial scale (from grams to tens of kilograms sediment) and temporal scale (from months to 10 years) than is readily afforded through laboratory studies. The lysimeter facility is intended to capture the natural heterogeneity of moisture and temperature regimes in the vadose zone, the unsaturated subsurface region between the surface soil and the underlying aquifer. The 48 lysimeter columns, which contain various radionuclides (and stable iodine), were opened to rainfall infiltration on July 5, 2012. The objective of this report is to provide a status of the lysimeter facility operations and to compile data collected during FY13, including leachate volume, rainfall, and soil moisture and temperature in situ probe data. Radiological leachate data are not presented in this document but will be the subject of a separate document.1 Leachate samples were collected quarterly and shipped to Clemson University for radiological analyses. Rainfall, leachate volume, moisture and temperature probe data were collected continuously. During operations of the facility this year, there were four safety or technical concerns that required additional maintenance: 1) radioactivity was detected in one of the overflow bottles (captured water collected from the secondary containment that does not come in contact with the radiological source material); 2) rainwater accumulated within the sample-bottle storage sheds; 3) overflow containers collected more liquid than anticipated; and 4) significant spider infestation occurred in the sample-bottle storage sheds. To address the first three concerns, each of the lysimeter columns was re-plumbed to improve and to minimize the number of joint unions. To address the fourth concern regarding spiders, new sample-bottle water sheds were purchased and a pest control

  11. Physical barriers formed from gelling liquids: 1. numerical design of laboratory and field experiments

    International Nuclear Information System (INIS)

    Finsterle, S.; Moridis, G.J.; Pruess, K.; Persoff, P.

    1994-01-01

    The emplacement of liquids under controlled viscosity conditions is investigated by means of numerical simulations. Design calculations are performed for a laboratory experiment on a decimeter scale, and a field experiment on a meter scale. The purpose of the laboratory experiment is to study the behavior of multiple gout plumes when injected in a porous medium. The calculations for the field trial aim at designing a grout injection test from a vertical well in order to create a grout plume of a significant extent in the subsurface

  12. Contamination control and revegetation (Field trials)

    International Nuclear Information System (INIS)

    Robison, William L.; Stone, Earl L.

    1986-01-01

    The LLNL/DOE field program at Bikini Atoll began in 1977. The first few years were devoted to developing an adequate data base from which to do an updated dose assessment of Bikini and Eneu Islands. The results indicated that 137 Cs was the most significant radionuclide, actually accounting for more than 90% of the total estimated wholebody and bone marrow dose, and that the terrestrial food chain (especially coconut) was the most significant potential exposure pathway. Strontium-90 accounts for only about 507% of the total bone marrow dose and the transuranics, 239+240 Pu and 241 Am, less than 1%. Thus, if the intake of 137 Cs can be reduced to 10% or less of its current concentration in food crops the radiological dose for Bikini Island would be within federal guidelines. However, samples of vegetation and soil will be analyzed for Sr and the transuranics to ensure an adequate data for evaluation of these radionuclide. In 1980, prior to the formation of the BARC, the goals of our Marshall Island program were extended to include an initial evaluation of methods to reduce the uptake of 137 Cs by food crops and/or reduce the 137 Cs soil inventory. We expanded one of our experiments and added two more when the BARC was formed and additional funding became available for evaluating the rehabilitation of Bikini Atoll

  13. Modern control room design experience and speculation

    International Nuclear Information System (INIS)

    Smith, J.E.

    1993-01-01

    Can operators trained to use conventional control panels readily adapt to CRT based control rooms? Does automation make the design of good man-machine interfaces more or less difficult? In a conventional, hard-wired control room is the operator's peripheral vision always an asset and how can one do better in a CRT based control room? Are Expert System assisted man-machine interfaces a boon or a bust? This paper explores these questions in the light of actual experience with advanced power plant control environments. This paper discusses how automation has in fact simplified the problem of ensuring that the operator has at all times a clear understanding of the plant state. The author contends that conventional hard-wired control rooms are very poor at providing the operator with a good overview of the plant status particularly under startup, or upset conditions and that CRT-based control rooms offer an opportunity for improvement. Experience with some early attempts at this are discussed together with some interesting proposals from other authors. Finally the paper discusses the experience to date with expert system assisted man-machine interfaces. Although promising for the future progress has been slow. The amount of knowledge research required is often formidable and consequently costly. Often when an adequate knowledge base is finally acquired it turns out to be better to use it to increase the level of automation and thus simplify the operator's task. The risks are not any greater and automation offers more consistent operation. It is important also to carefully distinguish between expert system assisted display selection and expert system operator guidance. The first is intended to help the operator in his quest for information. The second attempts to guide the operator actions. The good and the bad points of each of these approaches is discussed

  14. Control of Flowing Liquid Films By Electrostatic Fields in Space

    Science.gov (United States)

    Bankoff, S. George; Miksis, Michael J.; Kim, Hyo

    1996-01-01

    A novel type of lightweight space radiator has been proposed which employs internal electrostatic fields to stop coolant leaks from punctures caused by micrometeorites or space debris. Extensive calculations have indicated the feasibility of leak stoppage without film destabilization for both stationary and rotating designs. Solutions of the evolution equation for a liquid-metal film on an inclined plate, using lubrication theory for low Reynolds numbers, Karman-Pohlhausen quadratic velocity profiles for higher Reynolds numbers, and a direct numerical solution are shown. For verification an earth-based falling-film experiment on a precisely-vertical wall with controllable vacuum on either side of a small puncture is proposed. The pressure difference required to start and to stop the leak, in the presence and absence of a strong electric field, will be measured and compared with calculations. Various parameters, such as field strength, film Reynolds number, contact angle, and hole diameter will be examined. A theoretical analysis will be made of the case where the electrode is close enough to the film surface that the electric field equation and the surface dynamics equations are coupled. Preflight design calculations will be made in order to transfer the modified equipment to a flight experiment.

  15. Control of the radial electric field shear by modification of the magnetic field configuration in LHD

    International Nuclear Information System (INIS)

    Ida, K.; Yoshinuma, M.; Yokoyama, M.

    2005-01-01

    Control of the radial electric field, E γ , is considered to be important in helical plasmas, because the radial electric field and its shear are expected to reduce neoclassical and anomalous transport, respectively. In general, the radial electric field can be controlled by changing the collisionality, and positive or negative electric field have been obtained by decreasing or increasing the electron density, respectively. Although the sign of the radial electric field can be controlled by changing the collisionality, modification of the magnetic field is required to achieve further control of the radial electric field, especially producing a strong radial electric field shear. In the Large Helical Device (LHD) the radial electric field profiles are shown to be controlled by the modification of the magnetic field by 1) changing the radial profile of the helical ripples, ε h , 2) creating a magnetic island with an external perturbation field coil and 3) changing the local island divertor coil current. (author)

  16. Control of the radial electric field shear by modification of the magnetic field configuration in LHD

    International Nuclear Information System (INIS)

    Ida, K.; Yoshinuma, M.; Yokoyama, M.

    2005-01-01

    Control of the radial electric field, E r , is considered to be important in helical plasmas, because the radial electric field and its shear are expected to reduce neoclassical and anomalous transport, respectively. In general, the radial electric field can be controlled by changing the collisionality, and positive or negative electric fields have been obtained by decreasing or increasing the electron density, respectively. Although the sign of the radial electric field can be controlled by changing the collisionality, modification of the magnetic field is required to achieve further control of the radial electric field, especially to produce a strong radial electric field shear. In the Large Helical Device (LHD) the radial electric field profiles are shown to be controlled by the modification of the magnetic field by (1) changing the radial profile of the effective helical ripples, ε h (2) creating a magnetic island with an external perturbation field coil and (3) changing the local island divertor coil current

  17. Bacterial Transport in Heterogeneous Porous Media: Laboratory and Field Experiments

    Science.gov (United States)

    Fuller, M. E.

    2001-12-01

    A fully instrumented research site for examining field-scale bacterial transport has been established on the eastern shore of Virginia. Studies employing intact sediment cores from the South Oyster site have been performed to examine the effects of physical and chemical heterogeneity, to derive transport parameters, and to aid in the selection of bacterial strains for use in field experiments. A variety of innovative methods for tracking bacteria were developed and evaluated under both laboratory and field conditions, providing the tools to detect target cell concentrations in groundwater down to effects of physical and chemical heterogeneity on field-scale bacterial transport. The results of this research not only contribute to the development of more effective bioremediation strategies, but also have implications for a better understanding of bacterial movement in the subsurface as it relates to public health microbiology and general microbial ecology.

  18. Computer controls for the WITCH experiment

    CERN Document Server

    Tandecki, M; Van Gorp, S; Friedag, P; De Leebeeck, V; Beck, D; Brand, H; Weinheimer, C; Breitenfeldt, M; Traykov, E; Mader, J; Roccia, S; Severijns, N; Herlert, A; Wauters, F; Zakoucky, D; Kozlov, V; Soti, G

    2011-01-01

    The WITCH experiment is a medium-scale experimental set-up located at ISOLDE/CERN. It combines a double Penning trap system with,a retardation spectrometer for energy measurements of recoil ions from beta decay. For a correct operation of such a set-up a whole range of different devices is required. Along with the installation and optimization of the set-up a computer control system was developed to control these devices. The CS-Framework that is developed and maintained at GSI, was chosen as a basis for this control system as it is perfectly suited to handle the distributed nature of a control system.We report here on the required hardware for WITCH, along with the basis of this CS-Framework and the add-ons that were implemented for WITCH. (C) 2010 Elsevier B.V. All rights reserved.

  19. The electromagnetic bio-field: clinical experiments and interferences.

    Science.gov (United States)

    Burnei, G; Hodorogea, D; Georgescu, I; Gavriliu, Ş; Drăghici, I; Dan, D; Vlad, C; Drăghici, L

    2012-06-12

    One of the most important factors is the technical and scientifically rapid development that is continually modifying the world we live in and polluting it with electromagnetic radiations. A functional and structural influence of magnetic and electromagnetic field on living organisms is presented in the literature by many performed experiments. The notion of bio-field represents the electromagnetic field generated by the bio-structures, not only in their normal physiological activities but also in their pathological states. There is a tight interdependency between the bio-field and the bio-structure, which respects the primary notion of an electromagnetic field given by the Maxwell-Faraday laws, in which, the electromagnetic phenomena are simplified to the field variations. These variations can be expressed in a coherent differential equation system that bounds the field vectors to different space points at different time moments. The living organisms cannot contain electrostatic and magneto-static fields due to the intense activity of the bio-structures. The biochemical reactions that have high rhythms and speeds always impose the electrodynamics character of the biologic field that also corresponds to the stability of the protein molecule that can be explained only through a dynamic way. The existent energy is not considered an exciting agent, and it does not lead to any effects. The parameters of these elementary bio-fields cannot yet be fully known due to technical reasons. The biological structures are very complex ones and undergo continuous dynamical activity. That is why the calculus model should be related to the constant dynamics, nowadays being very difficult to express.

  20. Controlled environment experiments in pollution studies

    Energy Technology Data Exchange (ETDEWEB)

    Zeitzschel, B

    1978-12-01

    In the last decade society has become aware of the increasing negative effects of human waste products introduced to the oceans. There is proof evidence, at least for some areas of the world ocean, that the marine environment is seriously in danger. The scientific community is very concerned, arguing that there is an urgent need for basic research in this field because too little is known on the harzardous effects of man-made pollutants on the structure and functioning of marine ecosystems. There are two wanys to perform experiments under conrolled environment conditions: (1) in the laboratory; (2) in in-situ experiments with enclosures. Most laboratory experiments are designed to study the influence and the tolerance spectrum of specific pollutants, e.g. copper or DDT, on any specific organism, e.g. a mussel or a fish. In these experiments it is fairly difficult to simulate natural conditions. The concentrations of the pollutants are generally fairly high, often several orders of magnitude higher than in the ocean. It is questionable if the results from these experiments can be extrapolated to nature. In the second approach (enclosures of various sizes in-situ or in landbased facilities), fibre-glass containers and plastic bags have been used successfully in the last years, e.g. in the UK, USA, Canada, France, and W. Germany. The main goal of these experiments is to study the long-term effect of low-level perturbations on natural populations of the pelagic or benthic ecosystem. Examples of recent results are discussed in detail. 33 references.

  1. Experiment on thermohydraulics of simulated control rod

    International Nuclear Information System (INIS)

    Ogawa, Masuro; Ouchi, Mitsuo; Akino, Norio; Fujimura, Kaoru; Shiina, Yasuaki; Kawamura, Hiroshi

    1984-10-01

    A thermohydraulic study of a control rod channel is required for the core design of the Very High Temperature Gas Cooled Reactor (VHTR). A non-heating experiment with air flow was performed prior to heating experiment with helium flow. Experimental results on stability of flow, flow rate distribution and pressure drop of the control rod channel are reported. In a test section of the experimental apparatus, five simulated control subrods were suspended vertically in a circular duct. Their dimension was in coincide with those of the Detailed Disign (I) of the VHTR. Air of atomospheric pressure was used as a coolant gas, which flowed in inner and outer paths of the subrods. Total flow rate ranged from 0.0011 to 0.0062 kg/s. Flow rate distribution and pressure drop were obtained for various flow rates. Velocity fluctuation in the channel was also observed using a hot wire anemometer. From these experiments, it was found that the flow rate distribution was nearly the same as a disigned value and that turbulent and laminar flows were simultaneously realized in outer and inner paths respectively. These observations supported a feasibility of the present design. (author)

  2. Magnetic sensorless control experiment without drift problem on HT-7

    International Nuclear Information System (INIS)

    Nakamura, K.; Luo, J.R.; Wang, H.Z.; Ji, Z.S.; Wang, H.; Wang, F.; Qi, N.; Sato, K.N.; Hanada, K.; Sakamoto, M.; Idei, H.; Hasegawa, M.; Iyomasa, A.; Kawasaki, S.; Nakashima, H.; Higashijima, A.

    2006-01-01

    Magnetic sensorless control experiments of the plasma horizontal position have been carried out in the superconducting tokamak HT-7. Previously the horizontal position was calculated from the vertical field coil current and voltage without using signals of magnetic sensors like magnetic coils and flux loops placed near the plasma. The calculations are made focusing on the ripple frequency component of the power supply with thyristor and directly from them without time integration. There is no drift problem of integrator of magnetic sensors. Two kinds of experiments were carried out, to keep the position constant and swing the position in a triangular waveform

  3. Field-scale colloid migration experiments in a granite fracture

    International Nuclear Information System (INIS)

    Vilks, P.; Frost, L.H.; Bachinski, D.B.

    1997-01-01

    An understanding of particle migration in fractured rock, required to assess the potential for colloid-facilitated transport of radionuclides, can best be evaluated when the results of laboratory experiments are demonstrated in the field. Field-scale migration experiments with silica colloids were carried out at AECL's Underground Research Laboratory (URL), located in southern Manitoba, to develop the methodology for large-scale migration experiments and to determine whether colloid transport is possible over distances up to 17 m. In addition, these experiments were designed to evaluate the effects of flow rate and flow path geometry, and to determine whether colloid tracers could be used to provide additional information on subsurface transport to that provided by conservative tracers alone. The colloid migration studies were carried out as part of AECL's Transport Properties in Highly Fractured Rock Experiment, the objective of which was to develop and demonstrate methods for evaluating the solute transport characteristics of zones of highly fractured rock. The experiments were carried out within fracture zone 2 as two-well recirculating, two-well non-recirculating, and convergent flow tests, using injection rates of 5 and 101 min -1 . Silica colloids with a 20 nm size were used because they are potentially mobile due to their stability, small size and negative surface charge. The shapes of elution profiles for colloids and conservative tracers were similar, demonstrating that colloids can migrate over distances of 17 m. The local region of drawdown towards the URL shaft affected colloid migration and, to a lesser extent, conservative tracer migration within the flow field established by the two-well tracer tests. These results indicate that stable colloids, with sizes as small as 20 nm, have different migration properties from dissolved conservative tracers. (author)

  4. Active MHD control experiments in RFX-mod

    International Nuclear Information System (INIS)

    Ortolani, Sergio

    2006-01-01

    The RFX reversed field pinch experiment has been modified (RFX-mod) to address specific issues of active control of MHD instabilities. A thin shell (τ Bv ∼50 ms) has replaced the old thick one (τ Bv ∼500 ms) and 192 (4 poloidal x 48 toroidal) independently powered saddle coils surround the thin shell forming a cage completely covering the torus. This paper reports the results obtained during the first year of operation. The system has been used with various control scenarios including experiments on local radial field cancellation over the entire torus surface to mimic an ideal wall ('virtual shell') and on single and multiple mode feedback control. Successful virtual shell operation has been achieved leading to: a 3-fold increase in pulse length and well controlled 300 ms pulses(∼6 shell times) up to ∼1 MA plasma current; one order of magnitude reduction of the dominant radial field perturbations at the plasma edge and correspondingly 100% increase in global energy confinement time. Robust feedback stabilization of resistive wall modes has been demonstrated in conditions where rotation does not play a role and multiple unstable modes are present

  5. "Eu? Eu estou aí, compondo o mundo." Uma experiência de controle de endemia, pesquisa e participação popular vivida em Cansanção, Minas Gerais, Brasil "Me? I'm just here, part of the world". A field experience on endemic disease control in Cansanção, Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Rosinha Borges Dias

    1998-01-01

    Full Text Available Este artigo relata uma experiência de controle da doença de Chagas, vivida na década de 80 em um povoado rural do Vale do Jequitinhonha, MG, e reavaliada recentemente. Trata-se de um projeto de pesquisa-ação participativa, com aplicação na área de educação popular em saúde. Teve como objetivo conhecer, do ponto de vista dos sujeitos, o significado da doença de Chagas na vida de uma comunidade endêmica, procurando com eles alternativas de controle. Apesar da altíssima prevalência, a doença não chegava a ser prioridade sentida pela população, que vivia em situação de carências múltiplas e de luta pela sobrevivência. O controle da doença deu-se de forma integrada com outras necessidades. Levantam-se pistas para trabalhos de participação no controle de endemias, levando-se em conta a sabedoria popular, a visão integrada dos problemas e na mobilização em torno de interesses concretos. Destacam-se como necessários: a mudança nas relações entre o agente externo e a comunidade, a reciprocidade do envolvimento, a postura de 'escuta' e de solidariedade, o autodiagnóstico, a organização da população.This article reports an experience with Chagas' disease control involving community participation in the Jequitinhonha Valley (Minas Gerais, Brazil implemented during the 1980s, as an action-based participant research project of Popular Education. The main objective was to investigate the meaning of Chagas' disease from the community's perspective, seeking alternative control measures with their participation. Despite the extremely high prevalence of the disease, it was no perceived as a priority by the population, who were living in destitution and simply fighting for their very survival. Chagas' disease control was performed in an integrated manner, taking other community needs into account. The article suggests some forms of participation in the control of endemic diseases, taking into account the people's knowledge, in

  6. French LMFBR's control rods experience and development

    International Nuclear Information System (INIS)

    Arnaud, G.; Guigon, A.; Verset, L.

    1983-06-01

    Since the last ten years, the French program has been, first of all, directed to the setting up, and then the development of, at once, the Phenix control rods, and next, the Super-Phenix ones. The vented pin design, with porous plug and sodium bonding, which allows the choices of large diameters, has been taken, since the Rapsodie experience was decisive. The absorber material is sintered, 10 B enriched, boron carbide. The can is made of 316 type stainless steel, stabilised, or not, with titanium. The experience gained in Phenix up to now is important, and deals with about six loads of control rods. Results confirm the validity of the design of the absorber pins. Some difficulties has been encountered for the guiding devices, due to the swelling of the steel. They have required design and material improvements. Such difficulties are discarded by a new design of the bearing, for the Super-Phenix control rods. The other parts of these rods, from the Primary Shut-Down System, are strictly derived from Phenix. The design of the rods from the Secondary Shut-Down System is rather different, but it's not the case for the design of the absorber pins: in many a way, they are derived from Phenix pins and from Rapsodie control rods. Both types of rods irradiation tests are in progress in Phenix [fr

  7. Sound field control for a low-frequency test facility

    DEFF Research Database (Denmark)

    Pedersen, Christian Sejer; Møller, Henrik

    2013-01-01

    The two largest problems in controlling the reproduction of low-frequency sound for psychoacoustic experiments is the effect of the room due to standing waves and the relatively large sound pressure levels needed. Anechoic rooms are limited downward in frequency and distortion may be a problem even...... at moderate levels, while pressure-field playback can give higher sound pressures but is limited upwards in frequency. A new solution that addresses both problems has been implemented in the laboratory of Acoustics, Aalborg University. The solution uses one wall with 20 loudspeakers to generate a plane wave...... that is actively absorbed when it reaches the 20 loudspeakers on the opposing wall. This gives a homogeneous sound field in the majority of the room with a flat frequency response in the frequency range 2-300 Hz. The lowest frequencies are limited to sound pressure levels in the order of 95 dB. If larger levels...

  8. IKONET: distributed accelerator and experiment control

    International Nuclear Information System (INIS)

    Koldewijn, P.

    1986-01-01

    IKONET is a network consisting of some 35 computers used to control the 500 MeV Medium Energy Amsterdam electron accelerator (MEA) and its various experiments. The control system is distributed over a whole variety of machines, which are combined in a transparent central-oriented network. The local hardware is switched and tuned via Camac by a series of mini-computers with a real-time multitask operating system. Larger systems provide central intelligence for the higher-level control layers. An image of the complete accelerator settings is maintained by central database administrators. Different operator facilities handle touchpanels, multi-purpose knobs and graphical displays. The network provides remote login facilities and file servers. On basis of the present layout, an overview is given of future developments for subsystems of the network. (Auth.)

  9. Edge localized modes control: experiment and theory

    International Nuclear Information System (INIS)

    Becoulet, M.; Huysmans, G.; Thomas, P.; Joffrin, E.; Rimini, F.; Monier-Garbet, P.; Grosman, A.; Ghendrih, P.; Parail, V.; Lomas, P.; Matthews, G.; Wilson, H.; Gryaznevich, M.; Counsell, G.; Loarte, A.; Saibene, G.; Sartori, R.; Leonard, A.; Snyder, P.; Evans, T.; Gohil, P.; Moyer, R.; Kamada, Y.; Oyama, N.; Hatae, T.; Kamiya, K.; Degeling, A.; Martin, Y.; Lister, J.; Rapp, J.; Perez, C.; Lang, P.; Chankin, A; Eich, T.; Sips, A.; Stober, J.; Horton, L.; Kallenbach, A.; Suttrop, W.; Saarelma, S.; Cowley, S.; Loennroth, J.; Shimada, M.; Polevoi, A.; Federici, G.

    2005-01-01

    The paper reviews recent theoretical and experimental results focussing on the identification of the key factors controlling ELM energy and particle losses both in natural ELMs and in the presence of external controlling mechanisms. Present experiment and theory pointed out the benefit of the high plasma shaping, high q 95 and high pedestal density in reducing the ELM affected area and conductive energy losses in Type I ELMs. Small benign ELMs regimes in present machines (EDA, HRS, Type II, Grassy, QH, Type III in impurity seeded discharges at high δ ) and their relevance for ITER are reviewed. Recent studies of active control of ELMs using stochastic boundaries, small pellets and edge current generation are presented

  10. From Perceptual Apparatus to Immersive Field of Experience

    DEFF Research Database (Denmark)

    Wieczorek, Izabela

    2014-01-01

    Peter Sloterdijk ascribes to architecture the “the design of immersions” and hence the “production of embedding situations” or atmosphere (2011 (2006): 108-109), which as devised by Gernot Böhme becomes a fundamental concept of a new aesthetics (1993). Atmosphere implies affective immersion...... the immersive experiences relocate the vision within a “carnal density” (1992: 150), regaining all sensory modalities. Diverse perceptual apparatuses also defined a larger disciplinary expansion in the field of architecture and design. Conceived as sensorial activators, intensifiers of phenomena......, constitute a framework for a re-invention of perceptual worlds, providing a basis for tracing the conceptual contours of atmospheric perception, as well as for discerning the means of the production of space understood as an immersive field of experience. References: Böhme, G. (1993). "Atmosphere...

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

    Science.gov (United States)

    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.

  12. Tuning the Mass of Chameleon Fields in Casimir Force Experiments

    CERN Document Server

    Brax, Ph; Davis, A C; Shaw, D J; Iannuzzi, D

    2010-01-01

    We have calculated the chameleon pressure between two parallel plates in the presence of an intervening medium that affects the mass of the chameleon field. As intuitively expected, the gas in the gap weakens the chameleon interaction mechanism with a screening effect that increases with the plate separation and with the density of the intervening medium. This phenomenon might open up new directions in the search of chameleon particles with future long range Casimir force experiments.

  13. Targets with thin ferromagnetic layers for transient field experiments

    International Nuclear Information System (INIS)

    Gallant, J.L.; Dmytrenko, P.

    1982-01-01

    Multilayer targets containing a central layer sufficiently thin so that all recoil nuclei can traverse it and subsequently stop in a suitable cubic environment have been prepared. Such targets are required in experiments making use of a magnetic field acting on an ion moving through a ferromagnetic material. The preparation and annealing of the ferromagnetic foils (iron and gadolinium) and the fabrication of the multilayer targets are described. (orig.)

  14. Prosocial Behavior and Subjective Insecurity in Violent Contexts: Field Experiments

    OpenAIRE

    V?lez, Mar?a Alejandra; Trujillo, Carlos Andres; Moros, Lina; Forero, Clemente

    2016-01-01

    Subjective insecurity is a key determinant of different forms of prosocial behavior. In Study 1, we used field experiments with farmers in Colombian villages exposed to different levels of violence to investigate how individual perceptions of insecurity affect cooperation, trust, reciprocity and altruism. To do so, we developed a cognitive-affective measure of subjective insecurity. We found that subjective insecurity has a negative effect on cooperation but influences trust and altruism posi...

  15. OVERCONFIDENCE, OMENS AND EMOTIONS: RESULTS FROM A FIELD EXPERIMENT

    OpenAIRE

    Maria De Paola; Francesca Gioia; Vincenzo Scoppa

    2013-01-01

    We analyze how overconfidence is affected by superstitious beliefs and emotions induced by positive and negative stimuli in a field experiment involving about 700 Italian students who were randomly assigned to numbered seats in their written examination sessions. According to widespread superstitions, some numbers are considered lucky, while others are considered unlucky. At the end of the examination, we asked students the grade they expected to get. We find that students tend to be systemat...

  16. An Integral, Multidisciplinary and Global Geophysical Field Experience for Undergraduates

    Science.gov (United States)

    Vázquez, O.; Carrillo, D. J.; Pérez-Campos, X.

    2007-05-01

    The udergraduate program of Geophysical Engineering at the School of Engineering, of the Univesidad Nacional Autónoma de México (UNAM), went through an update process that concluded in 2006. As part of the program, the student takes three geophysical prospecting courses (gravity and magnetics, electric, electromagnetics, and seismic methods). The older program required a three-week field experience for each course in order to gradute. The new program considers only one extended field experience. This work stresses the importance of international academic exchange, where undergraduate students could participate, such as the Summer of Applied Geophysical Experience (SAGE), and interaction with research programs, such as the MesoAmerican Subduction Experiment (MASE). Also, we propose a scheeme for this activity based on those examples; both of them have in common real geophysical problems, from which students could benefit. Our proposal covers academic and logistic aspects to be taken into account, enhancing the relevance of interaction between other academic institutions, industry, and UNAM, in order to obtain a broader view of geophysics.

  17. The control architecture of the D0 experiment

    International Nuclear Information System (INIS)

    J. Fredrick Bartlett et al.

    2002-01-01

    From a controls viewpoint, contemporary high energy physics collider detectors are comparable in complexity to small to medium size accelerators: however, their controls requirements often differ significantly. D0, one of two collider experiments at Fermilab, has recently started a second, extended running period that will continue for the next five years. EPICS [1], an integrated set of software building blocks for implementing a distributed control system, has been adapted to satisfy the slow controls needs of the D0 detector by (1) extending the support for new device types and an additional field bus, (2) by the addition of a global event reporting system that augments the existing EPICS alarm support, and (3) by the addition of a centralized database with supporting tools for defining the configuration of the control system. This paper discusses the control architecture of the current D0 experiment, how the EPICS system was extended to meet the control requirements of a large, high-energy physics detector, and how a formal control system contributes to the management of detector operations

  18. Basic radiological studies contamination control experiments

    International Nuclear Information System (INIS)

    Duce, S.W.; Winberg, M.R.; Freeman, A.L.

    1989-09-01

    This report describes the results of experiments relating to contamination control performed in support of the Environmental Restoration Programs Retrieval Project. During the years 1950 to 1970 waste contaminated with plutonium and other transuranic radionuclides was disposed of in shallow land-filled pits and trenches at the Idaho National Engineering Laboratory. Due to potential for migration of radionuclides to an existing aquifer the feasibility of retrieving and repackaging the waste for placement in a final repository is being examined as part of a retrieval project. Contamination control experiments were conducted to determine expected respirable and nonrespirable plutonium contaminated dust fractions and the effectiveness of various dust suppression techniques. Three soil types were tested to determine respirable fractions: Rocky Flats Plant generic soil, Radioactive Waste Management Complex generic soil, and a 1:1 blend of the two soil types. Overall, the average respirable fraction of airborne dust was 5.4% by weight. Three contamination control techniques were studied: soil fixative sprays, misting agents, and dust suppression agents. All of the tested agents proved to be effective in reducing dust in the air. Details of product performance and recommended usage are discussed

  19. Dark matter effective field theory scattering in direct detection experiments

    Energy Technology Data Exchange (ETDEWEB)

    Schneck, K.; Cabrera, B.; Cerdeño, D. G.; Mandic, V.; Rogers, H. E.; Agnese, R.; Anderson, A. J.; Asai, M.; Balakishiyeva, D.; Barker, D.; Basu Thakur, R.; Bauer, D. A.; Billard, J.; Borgland, A.; Brandt, D.; Brink, P. L.; Bunker, R.; Caldwell, D. O.; Calkins, R.; Chagani, H.; Chen, Y.; Cooley, J.; Cornell, B.; Crewdson, C. H.; Cushman, P.; Daal, M.; Di Stefano, P. C. F.; Doughty, T.; Esteban, L.; Fallows, S.; Figueroa-Feliciano, E.; Godfrey, G. L.; Golwala, S. R.; Hall, J.; Harris, H. R.; Hofer, T.; Holmgren, D.; Hsu, L.; Huber, M. E.; Jardin, D. M.; Jastram, A.; Kamaev, O.; Kara, B.; Kelsey, M. H.; Kennedy, A.; Leder, A.; Loer, B.; Lopez Asamar, E.; Lukens, P.; Mahapatra, R.; McCarthy, K. A.; Mirabolfathi, N.; Moffatt, R. A.; Morales Mendoza, J. D.; Oser, S. M.; Page, K.; Page, W. A.; Partridge, R.; Pepin, M.; Phipps, A.; Prasad, K.; Pyle, M.; Qiu, H.; Rau, W.; Redl, P.; Reisetter, A.; Ricci, Y.; Roberts, A.; Saab, T.; Sadoulet, B.; Sander, J.; Schnee, R. W.; Scorza, S.; Serfass, B.; Shank, B.; Speller, D.; Toback, D.; Upadhyayula, S.; Villano, A. N.; Welliver, B.; Wilson, J. S.; Wright, D. H.; Yang, X.; Yellin, S.; Yen, J. J.; Young, B. A.; Zhang, J.

    2015-05-18

    We examine the consequences of the effective field theory (EFT) of dark matter–nucleon scattering for current and proposed direct detection experiments. Exclusion limits on EFT coupling constants computed using the optimum interval method are presented for SuperCDMS Soudan, CDMS II, and LUX, and the necessity of combining results from multiple experiments in order to determine dark matter parameters is discussed. We demonstrate that spectral differences between the standard dark matter model and a general EFT interaction can produce a bias when calculating exclusion limits and when developing signal models for likelihood and machine learning techniques. We also discuss the implications of the EFT for the next-generation (G2) direct detection experiments and point out regions of complementarity in the EFT parameter space.

  20. Experiments with a magnetically controlled pendulum

    International Nuclear Information System (INIS)

    Kraftmakher, Yaakov

    2007-01-01

    A magnetically controlled pendulum is used for observing free and forced oscillations, including nonlinear oscillations and chaotic motion. A data-acquisition system stores the data and displays time series of the oscillations and related phase plane plots, Poincare maps, Fourier spectra and histograms. The decay constant of the pendulum can be modified by positive or negative feedback. The apparatus, except for the data-acquisition system, is extremely simple and low cost, and can be assembled in a short time. The wide possibilities of varying the parameters of the pendulum make the experiments suitable for student projects

  1. Electronic ground support equipment for the Cluster Electric Field and Wave Experiment

    International Nuclear Information System (INIS)

    Sten, T.A.

    1992-10-01

    In a collaboration between ESA and NASA, ionosphere plasma structures will be studied by four indentical space probes to be launched in 1995 from French Guiana. The Electric Field and Wave (EFW) experiment will be designed to measure electric field and density fluctations by means of four sensors, each deployed on a 50 meter wire boom. In order to perform comprehensive tests and calibrations of the EFW experiment, computer controlled electronic ground support equipment has been developed. This report describes the hardware of the equipment, produced and assembled at the University of Oslo. 15 figs

  2. Edge localized modes control: experiment and theory

    Energy Technology Data Exchange (ETDEWEB)

    Bedoulet, M.; Huysmans, G.; Thomas, P.; Joffrin, E.; Rimini, F.; Monier-Garbet, P.; Grosman, A.; Ghendrih, P. [Association Euratom-CEA, Centre d' Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee; Parail, V.; Lomas, P.; Matthews, G.; Wilson, H.; Gryaznevich, M.; Gonsell, G.; Loarte, A.; Saibene, G.; Sartori, R.; Leonard, A.; Snyder, P.; Evans, T.; Gohil, P.; Burell, H.; Moyer, R.; Kamada, Y.; Oyama, N.; Hatae, T.; Degeling, A.; Martin, Y.; Lister, J.; Rapp, J.; Perez, C.; Lang, P.; Chankin, A.; Eich, T.; Sips, A.; Stober, J.; Horton, L.; Kallenbach, A.; Suttrop, W.; Saarelma, S.; Cowley, S.; Lonnroth, J.; Kamiya, K.; Shimada, M.; Polevoi, A.; Federici, G

    2004-07-01

    The paper reviews recent theoretical and experimental results focusing on the identification of the key factors controlling ELM (energy localized mode) energy and particle losses both in natural ELMs and in the presence of external controlling mechanisms. The theoretical description of the most studied Type-I ELMs is progressing from linear MHD stability analysis for peeling and ballooning modes to the non-linear explosive models and transport codes. Present theories cannot predict the ELM size self-consistently, however they pointed out the benefit of the high plasma shaping, high q{sub 95} and high pedestal density in reducing the ELM affected area. The experimental data also suggest that the conductive energy losses in Type-I ELM can be controlled by working in specific plasma conditions. In particular, the existence of purely convective small Type-I ELMs regimes at high q{sub 95} (>4.5) with {delta}W{sub ELM}/W{sub ped}<5% was demonstrated in high triangularity ({delta} {approx} 0.5) plasmas in JET. Small benign ELMs regimes in present machines (EDA, HRS, Type-II, grassy, QH, Type-III in impurity seeded discharges at high {delta} and their relevance for ITER parameters are reviewed briefly. The absence of already developed ITER relevant high confinement scenarios with acceptable ELMs has motivated recent intensive experimental and theoretical studies of active control of ELMs. The possibility of suppression of Type-I ELMs in H-mode scenarios at constant confinement was demonstrated in DIII-D experiments with a stochastic boundary created by external coils. It has been demonstrated in AUG that small pellets can trigger Type-I ELMs with a frequency imposed by the pellet injector. Pellet induced ELMs are similar to the intrinsic Type-I ELMs with the same frequency. At the same time the confinement degradation due to the fuelling can be minimized with pellets small as compared to the gas injection. Recent plasma current ramp experiments (JET, COMPASS-D) and

  3. Edge localized modes control: experiment and theory

    International Nuclear Information System (INIS)

    Bedoulet, M.; Huysmans, G.; Thomas, P.; Joffrin, E.; Rimini, F.; Monier-Garbet, P.; Grosman, A.; Ghendrih, P.; Parail, V.; Lomas, P.; Matthews, G.; Wilson, H.; Gryaznevich, M.; Gonsell, G.; Loarte, A.; Saibene, G.; Sartori, R.; Leonard, A.; Snyder, P.; Evans, T.; Gohil, P.; Burell, H.; Moyer, R.; Kamada, Y.; Oyama, N.; Hatae, T.; Degeling, A.; Martin, Y.; Lister, J.; Rapp, J.; Perez, C.; Lang, P.; Chankin, A.; Eich, T.; Sips, A.; Stober, J.; Horton, L.; Kallenbach, A.; Suttrop, W.; Saarelma, S.; Cowley, S.; Lonnroth, J.; Kamiya, K.; Shimada, M.; Polevoi, A.; Federici, G.

    2004-01-01

    The paper reviews recent theoretical and experimental results focusing on the identification of the key factors controlling ELM (energy localized mode) energy and particle losses both in natural ELMs and in the presence of external controlling mechanisms. The theoretical description of the most studied Type-I ELMs is progressing from linear MHD stability analysis for peeling and ballooning modes to the non-linear explosive models and transport codes. Present theories cannot predict the ELM size self-consistently, however they pointed out the benefit of the high plasma shaping, high q 95 and high pedestal density in reducing the ELM affected area. The experimental data also suggest that the conductive energy losses in Type-I ELM can be controlled by working in specific plasma conditions. In particular, the existence of purely convective small Type-I ELMs regimes at high q 95 (>4.5) with ΔW ELM /W ped <5% was demonstrated in high triangularity (δ ∼ 0.5) plasmas in JET. Small benign ELMs regimes in present machines (EDA, HRS, Type-II, grassy, QH, Type-III in impurity seeded discharges at high δ and their relevance for ITER parameters are reviewed briefly. The absence of already developed ITER relevant high confinement scenarios with acceptable ELMs has motivated recent intensive experimental and theoretical studies of active control of ELMs. The possibility of suppression of Type-I ELMs in H-mode scenarios at constant confinement was demonstrated in DIII-D experiments with a stochastic boundary created by external coils. It has been demonstrated in AUG that small pellets can trigger Type-I ELMs with a frequency imposed by the pellet injector. Pellet induced ELMs are similar to the intrinsic Type-I ELMs with the same frequency. At the same time the confinement degradation due to the fuelling can be minimized with pellets small as compared to the gas injection. Recent plasma current ramp experiments (JET, COMPASS-D) and modelling (JETTO) demonstrated that the edge

  4. Supine Craniospinal Irradiation Using Intrafractional Junction Shifts and Field-in-Field Dose Shaping: Early Experience at Methodist Hospital

    International Nuclear Information System (INIS)

    South, Michael C.; Chiu, J. Kam; Teh, Bin S.; Bloch, Charles; Schroeder, Thomas M.; Paulino, Arnold C.

    2008-01-01

    Purpose: To describe our preliminary experience with supine craniospinal irradiation. The advantages of the supine position for craniospinal irradiation include patient comfort, easier access to maintain an airway for anesthesia, and reduced variability of the head tilt in the face mask. Methods and Materials: The cranial fields were treated with near lateral fields and a table angle to match their divergence to the superior edge of the spinal field. The collimator was rotated to match the divergence from the superior spinal field. The spinal fields were treated using a source to surface distance (SSD) technique with the couch top at 100 cm. When a second spinal field was required, the table and collimator were rotated 90 o to allow for the use of the multileaf collimator and so the gantry could be rotated to match the divergence of the superior spinal field. The multileaf collimator was used for daily dynamic featherings and field-in-field dose control. Results: With a median follow-up of 20.2 months, five documented failures and no cases of radiation myelitis occurred in 23 consecutive patients. No failures occurred in the junctions of the spine-spine or brain-spine fields. Two failures occurred in the primary site alone, two in the spinal axis alone, and one primary site failure plus distant metastasis. The median time to recurrence was 17 months. Conclusion: The results of our study have shown that supine approach for delivering craniospinal irradiation is not associated with increased relapses at the field junctions. To date, no cases of radiation myelitis have developed

  5. Recent Swedish experiences in 222Rn control

    International Nuclear Information System (INIS)

    Swedjemark, G.A.; Maekitalo, A.

    1990-01-01

    Swedish local authorities are responsible for decreasing 222 Rn progeny concentrations in homes in their municipalities. To obtain an overall view of their experiences, concerned national authorities sent a questionnaire in 1986 to local authorities. The results were intended to form one basis for decisions by the government regarding revised statements on financial contributions, limits, etc. The results were also intended to be of use to national authorities in determining limits and recommendations and to local authorities in their field work. One result of the survey was an enhanced interest in the Rn problem among Swedish politicians and the mass media. This increased attention resulted in new plans for continued work to decrease Rn levels indoors during 1987-1989, on both a national and a local level. The experiences of the local authorities show that Rn progeny concentrations decreased to below the design level in 95% of newly built houses investigated. It was also found that Rn progeny concentrations were below the limit for reconstruction in 53% of existing homes that previously had levels exceeding the limit

  6. Conceptual design for an air core 2 meg-amp reversed field experiment

    International Nuclear Information System (INIS)

    Hammer, C.F.

    1983-01-01

    The Los Alamos CTR Division is involved in the conceptual design of a next phase Reversed Field Pinch experiment. The paper will discuss, in general, some of the physics questions that the experiment will address. Also in more detail it will discuss the engineering parameters and the possible hardware design solutions. The experiment is designed to produce a plasma current of about 2 MA which can be sustained for about 200 ms. The electrical energy for the system is provided by a large motor generator set. An inductive energy store is used to drive the magnetizing and poloidal field windings. A capacitor bank provides the energy for the toroidal field windings. The current in both circuits is maintained by using SCR controlled transformer rectifiers

  7. Conceptual design for an AIR CORE 2 MEG-AMP Reversed field experiment

    International Nuclear Information System (INIS)

    Hammer, C.F.

    1983-01-01

    The Los Alamos CTR Division is involved in the conceptual design of a next phase Reversed Field Pinch experiment. The paper will discuss, in general, some of the physics questions that the experiment will address. Also in more detail it will discuss the engineering parameters and the possible hardware design solutions. The experiment is designed to produce a plasma current of about 2 MA which can be sustained for about 200 ms. The electrical energy for the system is provided by a large motor generator set. An inductive energy store is used to drive the magnetizing and poloidal field windings. A capacitor bank provides the energy for the toroidal field windings. The current in both circuits is maintained by using SCR controlled transformer rectifiers

  8. Magnetic Field Design for the LANL nEDM Experiment

    Science.gov (United States)

    Dadisman, Ryan

    2017-09-01

    A recent UCN source upgrade at LANSCE makes possible an order of magnitude advancement in the measurement of the neutron electric dipole moment by use of the familiar Ramsey method of separated oscillatory fields. A highly uniform B0 magnetic field is required to achieve sufficiently long spin-relaxation times and to suppress the false EDM caused by the geometric phase effect. We identified a multi-gap solenoid as an ideal candidate to simultaneously achieve the uniformity requirements, via optimization of the gap lengths between and current within different sections, and provide plentiful access to the fiducial region. Results from initial tests of the coil when installed in the magnetic shield house enclosing the experiment will be presented. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, under Award Number DE-SC-0014622.

  9. Brine Migration in Heated Salt: Lessons Learned from Field Experiments

    Science.gov (United States)

    Kuhlman, K. L.; Matteo, E. N.; Mills, M.

    2017-12-01

    We summarize several interesting brine migration related phenomena hinted at in field experiments from field testing related to salt radioactive waste repositories in Germany and the US. Past heater tests in salt have shown 1) thermal-hydrological-mechanical coupling is quite strong during both heating and cooling; 2) chemical composition of brine evolves during heating, and comprises a mix of several water sources; and 3) acid gas (HCl) generation has been observed during past heater tests and may have multiple mechanisms for formation. We present a heated brine migration test design, formulated with these complexities in mind. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc. for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-NA0003525.

  10. Incineration in the nuclear field. The SGN experience

    International Nuclear Information System (INIS)

    Carpentier, S.

    1993-01-01

    The operation of power reactors, like that of fuel fabrication and nuclear fuel reprocessing plants, generated substantial quantities of waste. A large share of this waste is low- and medium-level waste, which is also combustible. Similarly, a number of institutes, laboratories, and hospitals, in the course of their activities, generated waste which a portion is radioactive and combustible. The chief advantage of incineration is to minimize the volume of burnable waste treated, and to produce a residue termed 'ash'. SGN has built up 25 years of experience in this field. The incinerators have been designed and the incineration processes are specially studied by SGN

  11. French developments and experience in the field of inservice inspection

    International Nuclear Information System (INIS)

    Saglio, Robert; Destribats, M.-T.; Pigeon, Michel; Roule, Maurice; Touffait, A.-M.

    1979-01-01

    The French PWR nuclear plant program was at the origin of a large amount of R and D work in the field of inservice inspection. The actions which were undertaken may be split up into different levels: - the regulatory level, the R and D level, the design level, the flaw evaluation level. The first results of pre and inservice inspections are presented. The experience gained by French Atomic Energy Commission with new techniques like focussed ultrasonics transducers and multi frequencies Eddy current apparatus are discussed

  12. EFEDA - European field experiment in a desertification-threatened area

    Science.gov (United States)

    Bolle, H.-J.; Andre, J.-C.; Arrue, J. L.; Barth, H. K.; Bessemoulin, P.; Brasa, A.; De Bruin, H. A. R.; Cruces, J.; Dugdale, G.; Engman, E. T.

    1993-01-01

    During June 1991 more than 30 scientific teams worked in Castilla-La Mancha, Spain, studying the energy and water transfer processes between soil, vegetation, and the atmosphere in semiarid conditions within the coordinated European research project EFEDA (European Field Experiment in Desertification-threatened Areas). Measurements were made from the microscale (e.g., measurements on single plants) up to a scale compatible with the grid size of global models. For this purpose three sites were selected 70 km apart and heavily instrumented at a scale in the order of 30 sq km. Aircraft missions, satellite data, and movable equipment were deployed to provide a bridge to the larger scale. This paper gives a description of the experimental design along with some of the preliminary results of this successful experiment.

  13. On Storks and Babies: Correlation, Causality and Field Experiments

    Directory of Open Access Journals (Sweden)

    Lambrecht Anja

    2016-11-01

    Full Text Available The explosion of available data has created much excitement among marketing practitioners about their ability to better understand the impact of marketing investments. Big data allows for detecting patterns and often it seems plausible to interpret them as causal. While it is quite obvious that storks do not bring babies, marketing relationships are usually less clear. Apparent “causalities” often fail to hold up under examination. If marketers want to be sure not to walk into a causality trap, they need to conduct field experiments to detect true causal relationships. In the present digital environment, experiments are easier than ever to execute. However, they need to be prepared and interpreted with great care in order to deliver meaningful and genuinely causal results that help improve marketing decisions.

  14. Field Experiments Aimed To The Analysis of Flood Generation Processes

    Science.gov (United States)

    Carriero, D.; Iacobellis, V.; Oliveto, G.; Romano, N.; Telesca, V.; Fiorentino, M.

    The study of the soil moisture dynamics and of the climate-soil-vegetation interac- tion is essential for the comprehension of possible climatic change phenomena, as well as for the analysis of occurrence of extreme hydrological events. In this trend the theoretically-based distribution of floods recently derived by Fiorentino and Ia- cobellis, [ŞNew insights about the climatic and geologic control on the probability distribution of floodsT, Water Resources Research, 2001, 37: 721-730] demonstrated, by an application in some Southern Italy basins, that processes at the hillslope scale strongly influence the basin response by means of the different mechanisms of runoff generation produced by various distributions of partial area contributing. This area is considered as a stochastic variable whose pdf position parameter showed strong de- pendence on the climate as it can seen in the studied basins behavior: in dry zones, where there is the prevalence of the infiltration excess (Horton) mechanism, the basin water loss parameter decreases as basin area increases and the flood peak source area depends on the permeability of soils; in humid zones, with the prevalence of satu- ration excess (Dunne) process, the loss parameter seems independent from the basin area and very sensitive to simple climatic index while only small portion of the area invested by the storm contributes to floods. The purpose of this work is to investigate the consistency of those interpretations by means of field experiments at the hillslope scale to establish a parameterization accounting for soil physical and hydraulic prop- erties, vegetation characteristics and land-use. The research site is the catchment of River Fiumarella di Corleto, which is located in Basilicata Region, Italy, and has a drainage area of approximately 32 km2. The environment has a rather dynamic geo- morphology and very interesting features from the soil-landscape modeling viewpoint [Santini A., A. Coppola, N. Romano, and

  15. Barkhausen noise sensor with direct field control

    Czech Academy of Sciences Publication Activity Database

    Stupakov, Oleksandr

    2013-01-01

    Roč. 11, č. 1 (2013), s. 209-212 ISSN 1546-198X R&D Projects: GA ČR GP102/09/P108 Institutional research plan: CEZ:AV0Z10100520 Keywords : Barkhausen noise * field measurement * magnetic non-destructive testing Subject RIV: JB - Sensor s, Measurment, Regulation Impact factor: 0.558, year: 2013

  16. Digital servo control of random sound fields

    Science.gov (United States)

    Nakich, R. B.

    1973-01-01

    It is necessary to place number of sensors at different positions in sound field to determine actual sound intensities to which test object is subjected. It is possible to determine whether specification is being met adequately or exceeded. Since excitation is of random nature, signals are essentially coherent and it is impossible to obtain true average.

  17. Alkali Rydberg states in electromagnetic fields: computational physics meets experiment

    International Nuclear Information System (INIS)

    Krug, A.

    2001-11-01

    We study highly excited hydrogen and alkali atoms ('Rydberg states') under the influence of a strong microwave field. As the external frequency is comparable to the highly excited electron's classical Kepler frequency, the external field induces a strong coupling of many different quantum mechanical energy levels and finally leads to the ionization of the outer electron. While periodically driven atomic hydrogen can be seen as a paradigm of quantum chaotic motion in an open (decaying) quantum system, the presence of the non-hydrogenic atomic core - which unavoidably has to be treated quantum mechanically - entails some complications. Indeed, laboratory experiments show clear differences in the ionization dynamics of microwave driven hydrogen and non-hydrogenic Rydberg states. In the first part of this thesis, a machinery is developed that allows for numerical experiments on alkali and hydrogen atoms under precisely identical laboratory conditions. Due to the high density of states in the parameter regime typically explored in laboratory experiments, such simulations are only possible with the most advanced parallel computing facilities, in combination with an efficient parallel implementation of the numerical approach. The second part of the thesis is devoted to the results of the numerical experiment. We identify and describe significant differences and surprising similarities in the ionization dynamics of atomic hydrogen as compared to alkali atoms, and give account of the relevant frequency scales that distinguish hydrogenic from non-hydrogenic ionization behavior. Our results necessitate a reinterpretation of the experimental results so far available, and solve the puzzle of a distinct ionization behavior of periodically driven hydrogen and non-hydrogenic Rydberg atoms - an unresolved question for about one decade. Finally, microwave-driven Rydberg states will be considered as prototypes of open, complex quantum systems that exhibit a complicated temporal decay

  18. Call for action for setting up an infectious disease control action plan for disaster area activities: learning from the experience of checking suffering volunteers in the field after the Great East Japan Earthquake.

    Science.gov (United States)

    Takahashi, Kenzo; Kodama, Mitsuya; Kanda, Hideyuki

    2013-12-01

    After the Great East Japan Earthquake on March 11th, 2011, a journalist visited the disaster area with febrile symptoms and was diagnosed with measles of the D genotype, which is not indigenous to Japan. After continuing activities in disaster areas and Tokyo, 11 measles cases were reported, some of which were identified as genotype D. Meanwhile non-profit activities directed towards volunteers were offered including interviews to screen for subjective symptoms, check body temperature and advise volunteers to refrain from working in shelter areas during the period of sickness. As a consequence, disease transmission was controlled among volunteers. In disaster areas, anyone can be an infection vector. In order to prevent transmission of infectious diseases, a field action plan, which includes body temperature checks and standard precautions should be formulated and put into place. If the action plans are shared among local governments and non-governmental organizations (NGOs), they can become a norm and be expected to control infectious disease transmission.

  19. Experiment-Based Teaching in Advanced Control Engineering

    Science.gov (United States)

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

    2011-01-01

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

  20. Detector control system for an LHC experiment

    CERN Document Server

    Mato, P

    1998-01-01

    The purpose of this document is to provide the user requirements for a detector control system kernel for the LHC experiments following the ESA standard PSS-05 [1]. The first issue will be used to provide the basis for an evaluation of possible development philosophies for a kernel DCS. As such it will cover all the major functionality but only to a level of detail sufficient for such an evaluation to be performed. Many of the requirements are therefore intentionally high level and generic, and are meant to outline the functionality that would be required of the kernel DCS, but not yet to the level of the detail required for implementation. The document is also written in a generic fashion in order not to rule out any implementation technology.1

  1. Control of Levitating Particle in Ultrasound Field

    Directory of Open Access Journals (Sweden)

    Sukhanov Dmitry

    2018-01-01

    Full Text Available The experimental setup for ultrasonic controlled levitation in the air has been developed. Two phased arrays made of 91 ultrasonic radiators placed in front of each other are used. Arrays are focused in the region of particle levitation. The length of the focus area allows us to move the particles along it, controlling the standing waves through the phase difference of the two arrays.

  2. Controlling Charged Particles with Inhomogeneous Electrostatic Fields

    Science.gov (United States)

    Herrero, Federico A. (Inventor)

    2016-01-01

    An energy analyzer for a charged-particle spectrometer may include a top deflection plate and a bottom deflection plate. The top and bottom deflection plates may be non-symmetric and configured to generate an inhomogeneous electrostatic field when a voltage is applied to one of the top or bottom deflection plates. In some instances, the top and bottom deflection plates may be L-shaped deflection plates.

  3. Identifying Discrimination at Work: The Use of Field Experiments.

    Science.gov (United States)

    Pager, Devah; Western, Bruce

    2012-06-01

    Antidiscrimination law offers protection to workers who have been treated unfairly on the basis of their race, gender, religion, or national origin. In order for these protections to be invoked, however, potential plaintiffs must be aware of and able to document discriminatory treatment. Given the subtlety of contemporary forms of discrimination, it is often difficult to identify discrimination when it has taken place. The methodology of field experiments offers one approach to measuring and detecting hiring discrimination, providing direct observation of discrimination in real-world settings. In this article, we discuss the findings of two recent field experiments measuring racial discrimination in low wage labor markets. This research provides several relevant findings for researchers and those interested in civil rights enforcement: (1) it produces estimates of the rate of discrimination at the point of hire; (2) it yields evidence about the interactions associated with discrimination (many of which reveal the subtlety with which contemporary discrimination is practiced); and (3) it provides a vehicle for both research on and enforcement of antidiscrimination law.

  4. Potentials of two bio-pesticides in the control of some field insect ...

    African Journals Online (AJOL)

    A field experiment was carried out to determine the predominate order of insects associated with Bambara groundnut and to compare the efficacy of aqueous leaf extracts of Jatropha (Jatropha curcas) and lemon grass (Cymbopogon citratus), used as bio-pesticides in controlling some field insect pests of Bambara ...

  5. Transport and confinement studies in the RFX-mod reversed-field pinch experiment

    International Nuclear Information System (INIS)

    Innocente, P.; Alfier, A.; Carraro, L.; Lorenzini, R.; Pasqualotto, R.; Terranova, D.

    2007-01-01

    In the modified RFX experiment (RFX-mod) external magnetic field coils and a close fitting thin conductive shell control radial magnetic fields. In the so-called virtual shell (VS) operation, radial field zeroing at the thin shell radius is stationary provided by the feedback-controlled coils. First experiments on RFX-mod proved the capability of the active scheme to steadily reduce the radial magnetic field. Furthermore it has been found that such edge magnetic field control extends its beneficial effects to the whole plasma. With respect to the old RFX, where magnetohydrodynamic modes amplitude was controlled by the use of a passive thick conductive shell, a stationary 2- to 3-fold reduction of the B r field amplitude in the core is obtained. The reduction of field fluctuations positively reflects on confinement. In fact, a strong reduction of the loop voltage is observed and correspondingly a 3-fold increase in pulse length is achieved by using the same poloidal flux swing. Temperature and particle measurements confirm the improved confinement properties of the VS operation. With a lower ohmic input power, higher electron temperature and lower particle influx are measured. Particle and heat transport have been studied by means of a 1D code. Local power balance was used to compute the heat conductivity profile: for the VS discharges a lower conductivity over a significant region of the plasma is found. The improved properties of RFX-mod VS operation provide a better confinement scaling in terms of plasma current. The results show that compared with the thick shell configuration, a significant confinement improvement can be obtained under stationary conditions by actively controlling the plasma magnetic boundary

  6. [Runoff Pollution Experiments of Paddy Fields Under Different Irrigation Patterns].

    Science.gov (United States)

    Zhou, Jing-wen; Su, Bao-lin; Huang, Ning-bo; Guan, Yu-tang; Zhao, Kun

    2016-03-15

    To study runoff and non-point source pollution of paddy fields and to provide a scientific basis for agricultural water management of paddy fields, paddy plots in the Jintan City and the Liyang City were chosen for experiments on non-point source pollution, and flood irrigation and intermittent irrigation patterns were adopted in this research. The surface water level and rainfall were observed during the growing season of paddies, and the runoff amount from paddy plots and loads of total nitrogen (TN) and total phosphorus (TP) were calculated by different methods. The results showed that only five rain events of totally 27 rainfalls and one artificially drainage formed non-point source pollution from flood irrigated paddy plot, which resulted in a TN export coefficient of 49.4 kg · hm⁻² and a TP export coefficient of 1.0 kg · hm⁻². No any runoff event occurred from the paddy plot with intermittent irrigation even in the case of maximum rainfall of 95.1 mm. Runoff from paddy fields was affected by water demands of paddies and irrigation or drainage management, which was directly correlated to surface water level, rainfall amount and the lowest ridge height of outlets. Compared with the flood irrigation, intermittent irrigation could significantly reduce non-point source pollution caused by rainfall or artificial drainage.

  7. Crystal field parameters in UCl4: Experiment versus theory

    International Nuclear Information System (INIS)

    Zolnierek, Z.; Gajek, Z.; Khan Malek, C.

    1984-01-01

    Crystal field effect on U 4+ ion with the 3 H 4 ground term in tetragonal ligand field of UCl 4 has been studied in detail. Crystal field parameters determined experimentally from optical spectroscopy and magnetic susceptibility are in good agreement with CEP sets derived from the modified point charge model and the ab initio method. Theoretical calculations lead to overestimating the A 4 4 4 > and lowering the A 2 0 2 > values in comparison to those found in the experiments. The discrepancies are, however, within an accuracy of calculations. A large reduction of expectation values of the magnetic moment operator for the eigenvectors of lowest CF levels (17.8%), determined from magnetic susceptibility, cannot be attributed to the overlap and covalency effects only. The detailed calculations have shown that the latter effects provide about 4.6% reduction of respective matrix elements, and the applied J-J mixing procedure increases this factor up to 6.5%. Since similar, as in UCl 4 , reduction factor (proportional15%) has already been observed in a number of different uranium compounds, it seems to be likely that this feature is involved in the intrinsic properties of the U 4+ ion. We endeavor to explain this effect in terms of configuration interaction mechanisms. (orig.)

  8. Crystal field parameters in UCI 4: Experiment versus theory

    Science.gov (United States)

    Zolnierek, Z.; Gajek, Z.; Malek, Ch. Khan

    1984-08-01

    Crystal field effect on U 4+ ion with the 3H 4 ground term in tetragonal ligand field of UCl 4 has been studied in detail. Crystal field parameters determined experimentally from optical spectroscopy and magnetic susceptibility are in good agreement with CFP sets derived from the modified point charge model and the ab initio method. Theoretical calculations lead to overestimating the A44 and lowering the A02 values in comparison to those found in the experiments. The discrepancies are, however, within an accuracy of calculations. A large reduction of expectation values of the magnetic moment operator for the eigenvectors of lowest CF levels (17.8%), determined from magnetic susceptibility, cannot be attributed to the overlap and covalency effects only. The detailed calculations have shown that the latter effects provide about 4.6% reduction of respective matrix elements, and the applied J-J mixing procedure increases this factor up to 6.5%. Since similar, as in UCl 4, reduction factor(≈15%) has already been observed in a number of different uranium compounds, it seems likely that this feature is involved in the intrinsic properties of the U 4+ ion. We endeavor to explain this effect in terms of configuration interaction mechanisms.

  9. Multi-Disciplinary Research Experiences Integrated with Industry –Field Experiences

    Directory of Open Access Journals (Sweden)

    Suzanne Lunsford

    2015-10-01

    Full Text Available The purpose of this environmentally inquiry-based lab was to allow the students to engage into real-world concepts that integrate industry setting (Ohio Aggregate Industrial Mineral Association with the academia setting. Our students are engaged into a field trip where mining occurs to start the problem based learning of how the heavy metals leak in the mining process. These heavy metals such as lead and indium in the groundwater are a serious concern for the environment (Environmental Protection Agency from the mining process. The field experiences at the mining process assist in building our students interest in developing sensors to detect heavy metals of concern such as lead and indium simultaneously by a unique electrochemistry technique called Square Wave Anodic Stripping Voltammetry (SWASV. The field experience assists building the students interest in real –world application and what qualities do they want the electrochemical sensor to possess to be successful for real world usage. During the field trip the students are engaged into learning novel instrumentation such as an SEM (Scanning Electron Microscope to study the working electrode sensor developed to understand the sensor surface morphology properties better as well. The integration of industry setting with academia has been a positive experience for our students that has allowed their understanding of real-world science research needs to succeed in an industrial setting of research.

  10. Field Experiments on SAR Detection of Film Slicks

    Science.gov (United States)

    Ermakov, S.; da Silva, J. C. B.; Kapustin, I.; Sergievskaya, I.

    2013-03-01

    Field experiments on radar detection of film slicks using satellite synthetic aperture radar TerraSAR-X and X-band scatterometer on board a research vessel are described. The experiments were carried out with surfactant films with known physical parameters, the surface tension and the film elasticity, at low to moderate wind conditions and at different radar incidence angles. It is shown that the depression of radar backscatter (contrast) in films slicks for X-band SAR weakly depends on wind velocity/direction, film elasticity and incidence angles within the range of 200-400. Scatterometer contrasts obtained at incidence angles of about 600 are larger than SAR contrasts. Theoretical analysis of radar contrasts for low-to-moderate incidence angles has been carried out based on a hydrodynamic model of wind wave damping due to films and on a composite radar imaging model. The hydrodynamic model takes into account wave damping due to viscoelastic films, wind wave generation and a phenomenological term describing nonlinear limitation of the wind wave spectrum. The radar model takes into account Bragg scattering and specular scattering mechanisms, the latter is usually negligible compared to the Bragg mechanism at moderate incidence angles (larger than 30-35 degrees), but gives noticeable contribution to radar backscattering at smaller incidence angles particularly for slick areas when cm-scale ripples are strongly depressed by films. Calculated radar contrasts in slicks are compared with experiments and it is concluded that development of the model is needed to predict quantitatively observations.

  11. Data management for interdisciplinary field experiments: OTTER project support

    Science.gov (United States)

    Angelici, Gary; Popovici, Lidia; Skiles, J. W.

    1993-01-01

    The ability of investigators of an interdisciplinary science project to properly manage the data that are collected during the experiment is critical to the effective conduct of science. When the project becomes large, possibly including several scenes of large-format remotely sensed imagery shared by many investigators requiring several services, the data management effort can involve extensive staff and computerized data inventories. The OTTER (Oregon Transect Ecosystem Research) project was supported by the PLDS (Pilot Land Data System) with several data management services, such as data inventory, certification, and publication. After a brief description of these services, experiences in providing them are compared with earlier data management efforts and some conclusions regarding data management in support of interdisciplinary science are discussed. In addition to providing these services, a major goal of this data management capability was to adopt characteristics of a pro-active attitude, such as flexibility and responsiveness, believed to be crucial for the effective conduct of active, interdisciplinary science. These are also itemized and compared with previous data management support activities. Identifying and improving these services and characteristics can lead to the design and implementation of optimal data management support capabilities, which can result in higher quality science and data products from future interdisciplinary field experiments.

  12. A study on environmental pollution control in energy field

    Energy Technology Data Exchange (ETDEWEB)

    Min, B.M.; Son, J.E.; Lee, H.K.; Choi, W.K.; Baek, I.H.; Lee, J.S. [Korea Inst. of Energy Research, Taejon (Korea, Republic of)

    1995-12-01

    This report is contained such as following contents; Preparation of the stepwise pollution control strategies to reduce pollutants in energy field, which will be satisfy to tightened emission standard in the future. Analysis of the environmental pollution control technologies level, which related to energy field in domestic and other countries. Visualization of the reduction strategies of domestic carbon dioxide emission in energy field. And, discussion and proposal of the R and D program to improve the domestic environmental pollution control technologies in energy field. (author). 99 refs., 67 figs., 73 tabs.

  13. RF field control for Kaon Factory booster cavities

    International Nuclear Information System (INIS)

    Craig, S.T.; de Jong, M.S.

    1992-08-01

    A conceptual design is developed for control of the Kaon Factory booster rf accelerating fields. This design addresses control of cavity: tuning, voltage amplitude, and voltage phase angle. Time-domain simulations were developed to evaluate the proposed controllers. These simulations indicate that adequate tuning performance can be obtained with the combination of adaptive feed forward and proportional feedback control. Voltage amplitude and voltage phase can be adequately controlled using non-adaptive feed forward and proportional feedback control. (Author) (figs., tabs.)

  14. RF field control for KAON Factory booster cavities

    International Nuclear Information System (INIS)

    Craig, S.T.; de Jong, M.S.

    1990-11-01

    A conceptual design is developed for control of the KAON Factory Booster rf accelerating fields. This design addresses control of cavity: tuning, voltage amplitude, and voltage phase angle. Time-domain simulations were developed to evaluated the proposed controllers. These simulations indicated that adequate tuning performance can be obtained with the combination of adaptive feed-forward and proportional feedback control. Voltage amplitude and voltage phase can be adequately controlled using non-adaptive feedforward and proportional feedback control

  15. Toroidal magnetic field system for a 2-MA reversed-field pinch experiment

    International Nuclear Information System (INIS)

    Melton, J.G.; Linton, T.W.

    1983-01-01

    The engineering design of the toroidal magnetic field (TF) system for a 2-MA Reversed-Field Pinch experiment (ZT-H) is described. ZT-H is designed with major radius 2.15 meters, minor radius 0.40 meters, and a peak toroidal magnetic field of 0.85 Tesla. The requirement for highly uniform fields, with spatial ripple <0.2% leads to a design with 72 equally spaced circular TF coils, located at minor radius 0.6 meters, carrying a maximum current of 9.0 MA. The coils are driven by a 12-MJ capacitor bank which is allowed to ring in order to aid the reversal of magnetic field. A stress analysis is presented, based upon calculated hoop tension, centering force, and overturning moment, treating these as a combination of static loads and considering that the periodic nature of the loading causes little amplification. The load transfer of forces and moments is considered as a stress distribution resisted by the coils, support structures, wedges, and the structural shell

  16. Fate of diuron and linuron in a field lysimeter experiment.

    Science.gov (United States)

    Guzzella, L; Capri, E; Di Corcia, A; Barra Caracciolo, A; Giuliano, G

    2006-01-01

    The environmental fate of herbicides can be studied at different levels: in the lab with disturbed or undisturbed soil columns or in the field with suction cup lysimeters or soil enclosure lysimeters. A field lysimeter experiment with 10 soil enclosures was performed to evaluate the mass balance in different environmental compartments of the phenylurea herbicides diuron [3-(3,4-diclorophenyl)-1,1-dimethyl-urea] and linuron [3-(3,4-dichlorophenyl)-1-methoxy-1-methylurea]. After application on the agricultural soil, the herbicides were searched for in soil, pore water, and air samples. Soil and water samples were collected at different depths of the soil profile and analyzed to determine residual concentrations of both the parent compounds and of their main transformation products, to verify their persistence and their leaching capacity. Air volatilization was calculated using the theoretical profile shape method. The herbicides were detected only in the surface layer (0-10 cm) of soil. In this layer, diuron was reduced to 50% of its initial concentration at the end of the experiment, while linuron was still 70% present after 245 d. The main metabolites detected were DCPMU [3-(3,4-dichlorophenyl)-1-methylurea] and DCA (3,4-dichloroaniline). In soil pore water, diuron and linuron were detected at depths of 20 and 40 cm, although in very low concentrations. Therefore the leaching of these herbicides was quite low in this experiment. Moreover, volatilization losses were inconsequential. The calculated total mass balance showed a high persistence of linuron and diuron in the soil, a low mobility in soil pore water (less than 0.5% in leachate water), and a negligible volatilization effect. The application of the Pesticide Leaching Model (PELMO) showed similar low mobility of the chemicals in soil and water, but overestimated their volatilization and their degradation to the metabolite DCPMU. In conclusion, the use of soil enclosure lysimeters proved to be a good

  17. Control System Development Plan for the National Spherical Torus Experiment

    International Nuclear Information System (INIS)

    Neumeyer, C.; Mueller, D.; Gates, D.A.; Ferron, J.R.

    1999-01-01

    The National Spherical Torus Experiment (NSTX) has as one of its primary goals the demonstration of the attractiveness of the spherical torus concept as a fusion power plant. Central to this goal is the achievement of high plasma β ( = 2 micro 0 /B 2 a measure of the efficiency of a magnetic plasma confinement system). It has been demonstrated both theoretically and experimentally that the maximum achievable β is a strong function of both local and global plasma parameters. It is therefore important to optimize control of the plasma. To this end a phased development plan for digital plasma control on NSTX is presented. The relative level of sophistication of the control system software and hardware will be increased according to the demands of the experimental program in a three phase plan. During Day 0 (first plasma), a simple coil current control algorithm will initiate plasma operations. During the second phase (Day 1) of plasma operations the control system will continue to use the preprogrammed algorithm to initiate plasma breakdown but will then change over to a rudimentary plasma control scheme based on linear combinations of measured plasma fields and fluxes. The third phase of NSTX plasma control system development will utilize the rtEFIT code, first used on DIII-D, to determine, in real-time, the full plasma equilibrium by inverting the Grad-Shafranov equation. The details of the development plan, including a description of the proposed hardware will be presented

  18. Overlay control methodology comparison: field-by-field and high-order methods

    Science.gov (United States)

    Huang, Chun-Yen; Chiu, Chui-Fu; Wu, Wen-Bin; Shih, Chiang-Lin; Huang, Chin-Chou Kevin; Huang, Healthy; Choi, DongSub; Pierson, Bill; Robinson, John C.

    2012-03-01

    Overlay control in advanced integrated circuit (IC) manufacturing is becoming one of the leading lithographic challenges in the 3x and 2x nm process nodes. Production overlay control can no longer meet the stringent emerging requirements based on linear composite wafer and field models with sampling of 10 to 20 fields and 4 to 5 sites per field, which was the industry standard for many years. Methods that have emerged include overlay metrology in many or all fields, including the high order field model method called high order control (HOC), and field by field control (FxFc) methods also called correction per exposure. The HOC and FxFc methods were initially introduced as relatively infrequent scanner qualification activities meant to supplement linear production schemes. More recently, however, it is clear that production control is also requiring intense sampling, similar high order and FxFc methods. The added control benefits of high order and FxFc overlay methods need to be balanced with the increased metrology requirements, however, without putting material at risk. Of critical importance is the proper control of edge fields, which requires intensive sampling in order to minimize signatures. In this study we compare various methods of overlay control including the performance levels that can be achieved.

  19. Prosocial Behavior and Subjective Insecurity in Violent Contexts: Field Experiments

    Science.gov (United States)

    Vélez, María Alejandra; Trujillo, Carlos Andres; Moros, Lina; Forero, Clemente

    2016-01-01

    Subjective insecurity is a key determinant of different forms of prosocial behavior. In Study 1, we used field experiments with farmers in Colombian villages exposed to different levels of violence to investigate how individual perceptions of insecurity affect cooperation, trust, reciprocity and altruism. To do so, we developed a cognitive-affective measure of subjective insecurity. We found that subjective insecurity has a negative effect on cooperation but influences trust and altruism positively. In Study 2, carried out three years after Study 1, we repeated the initial design with additional measures of victimization. Our goal was to relate subjective insecurity with actual victimization. The findings of Study 2 support the initial results, and are robust and consistent for cooperative behavior and trust when including victimization as a mediator. Different indicators of victimization are positively correlated with subjective insecurity and an aggregate index of victimization has a negative effect on cooperation but exerts a positive influence on trust. PMID:27472437

  20. Field experience with KWU SG chemical cleaning process

    International Nuclear Information System (INIS)

    Odar, S.

    1989-01-01

    The ingress of corrosion products into PWR steam generators (SG's) their deposition and the subsequent concentration of salt impurities can induce a variety of mechanisms for corrosion attack on SG tubing. Already, some plants have had to replace their steam generators due to severe corrosion damage and others are seriously considering the same costly action in the near future. One of the most effective ways to counteract corrosion mechanisms and thus to reduce the likelihood of SG replacement becoming necessary is to clean the SG's and to keep them clean. For many years, the industry has been involved in developing different types of cleaning techniques. Among these, chemical cleaning has been shown to be especially effective. In this article, the KWU chemical cleaning process, for which there is considerable application experience, is described. The results of field applications will be presented together with material compatibility data and information on cleaning effectiveness. (author)

  1. Prosocial Behavior and Subjective Insecurity in Violent Contexts: Field Experiments.

    Directory of Open Access Journals (Sweden)

    María Alejandra Vélez

    Full Text Available Subjective insecurity is a key determinant of different forms of prosocial behavior. In Study 1, we used field experiments with farmers in Colombian villages exposed to different levels of violence to investigate how individual perceptions of insecurity affect cooperation, trust, reciprocity and altruism. To do so, we developed a cognitive-affective measure of subjective insecurity. We found that subjective insecurity has a negative effect on cooperation but influences trust and altruism positively. In Study 2, carried out three years after Study 1, we repeated the initial design with additional measures of victimization. Our goal was to relate subjective insecurity with actual victimization. The findings of Study 2 support the initial results, and are robust and consistent for cooperative behavior and trust when including victimization as a mediator. Different indicators of victimization are positively correlated with subjective insecurity and an aggregate index of victimization has a negative effect on cooperation but exerts a positive influence on trust.

  2. Prosocial Behavior and Subjective Insecurity in Violent Contexts: Field Experiments.

    Science.gov (United States)

    Vélez, María Alejandra; Trujillo, Carlos Andres; Moros, Lina; Forero, Clemente

    2016-01-01

    Subjective insecurity is a key determinant of different forms of prosocial behavior. In Study 1, we used field experiments with farmers in Colombian villages exposed to different levels of violence to investigate how individual perceptions of insecurity affect cooperation, trust, reciprocity and altruism. To do so, we developed a cognitive-affective measure of subjective insecurity. We found that subjective insecurity has a negative effect on cooperation but influences trust and altruism positively. In Study 2, carried out three years after Study 1, we repeated the initial design with additional measures of victimization. Our goal was to relate subjective insecurity with actual victimization. The findings of Study 2 support the initial results, and are robust and consistent for cooperative behavior and trust when including victimization as a mediator. Different indicators of victimization are positively correlated with subjective insecurity and an aggregate index of victimization has a negative effect on cooperation but exerts a positive influence on trust.

  3. Anomalous cross-field velocities in a CIV laboratory experiment

    International Nuclear Information System (INIS)

    Axnaes, I.

    1988-10-01

    The axial and radial ion velocities and the electron radial velocity are determined in coaxial plasma gun operated under critical velocity conditions. The particle celocities are determined from probe measurement together with He I 3889 AA absolute intensity measurements and the consideration of the total momentum balance of the current sheet. The ions are found move axially and the electrons radially much faster than predicted by the E/B drift in the macroscopic fields. These results agree with what can be expected from the instability processes, which has earlier been proposed to operate in these experiments. It is therefore a direct experimental demonstration that instability processes have to be invoked not only for the electron heating, but also to explain the macroscopic velocities and currents. (author)

  4. EVALUATION OF FOUR INTEGRATED PEST MANAGEMENT PACKAGES FOR CONTROLLING MAIN PESTS OF COTTON IN RAINFED FIELDS

    OpenAIRE

    Nurindah Nurindah; Dwi Adi Sunarto

    2014-01-01

    Cotton production nationally is low due to various constraints, including pests. Two main pests commonly found in cotton plantation in rain fed fields are cotton leafhopper (Amrasca biguttula) and cotton bollworm (Helicoverpa armigera). The study aimed to evaluate four packages of integrated pest management (IPM) techniques to control cotton leafhopper and cotton bollworm in rain fed fields. The experiment was conducted in farmers’ fields at Asembagus, East Java, between January and July 2012...

  5. Magnetic Field Monitoring in the SNS and LANL Neutron EDM Experiments

    Science.gov (United States)

    Aleksandrova, Alina; SNS nEDM Collaboration; LANL nEDM Collaboration

    2017-09-01

    The SNS neutron EDM experiment requires the ability to precisely control and monitor the magnetic field inside of the fiducial volume. However, it is not always practical (or even possible) to measure the field within the region of interest directly. To remedy this issue, we have designed a field monitoring system that will allow us to reconstruct the field inside of the fiducial volume using noninvasive measurements of the field components at discrete locations external to this volume. A prototype probe array (consisting of 12 single-axis fluxgate magnetometer sensors) was used to monitor the magnetic field within the fiducial volume of an in-house magnetic testing apparatus. In this talk, the design and results of this test will be presented, and the possible implementation of this field monitoring method may have in the room temperature LANL neutron EDM experiment will be discussed. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, under Award Number DE-SC-0014622.

  6. New indoor environment chambers and field experiment offices for research on human comfort, health and productivity

    DEFF Research Database (Denmark)

    Toftum, Jørn; Langkilde, Gunnar; Fanger, Povl Ole

    2004-01-01

    The article describes three new indoor environment chambers, a new laboratory for the study of air movement in spaces and five offices for controlled environment exposures of human subjects in field experiments at the International Centre for Indoor Environment and Energy, Technical University of...... of Denmark. Together with three older chambers, the Centre now has at its disposal 12 spaces for studying indoor environments and their impact on human comfort, health and productivity.......The article describes three new indoor environment chambers, a new laboratory for the study of air movement in spaces and five offices for controlled environment exposures of human subjects in field experiments at the International Centre for Indoor Environment and Energy, Technical University...

  7. Experiments on a Toroidal Screw Pinch with Various Field Programming

    Energy Technology Data Exchange (ETDEWEB)

    Zwicker, H.; Wilhelm, R.; Krause, H. [Max-Planck-Institut Fuer Plasmaphysik, EURATOM-Association, Garching, Munich, Federal Republic of Germany (Germany)

    1971-10-15

    In the toroidal screw pinch ISAR-IV (large diameter 60 cm, aspect ratio 5, maximum storage, energy 140 kj) attempts were made to get an improved stability of the plasma by different kinds of field programming. The best results were obtained with positive trapped B{sub z}-fields and simultaneous switching of main B{sub z}-field and I{sub z}-current. In this case the dense plasma column (n{sub e} Almost-Equal-To 2-3 x 10{sup 16} , kT Almost-Equal-To 50-100 eV, {beta} Almost-Equal-To 15-20%) is surrounded by a force-free plasma ({beta} = 1%) with weak shear and it behaves stably for, at least, 25 {mu}s. The resulting containment time nr of near 10{sup 12} s cm{sup -3} remains a factor of 2-3 below the upper limit given by the classical diffusion. The following loss of the equilibrium position near the coil axis ({Delta} Almost-Equal-To 1-2 cm) is connected to a strong damping of the axial plasma current which starts near the end of the containment. It may be assumed that the increase of the effective plasma resistance mainly results from a contact of the force-free regions with the tube wall. Attempts were made to improve the containment by suitable programming of a plasma z-current. The results are presented. Experiments with one quartz limiter inside the torus improved the equilibrium but introduced instabilities at the new surface of the dilute plasma. To obtain more information about the outer region, the dilute plasma was produced without a dense core and separated from the tube walls by weak adiabatic compression. Under these Tokamak-like conditions the q-value was varied. In the region of q Almost-Equal-To 1 there appeared instabilities which seem to haver higher m-modes and rather short wavelengths. In a different kind of field programming the field distribution of the ''diffuse pinch'' was realized within an accuracy of 5-10% (kT Almost-Equal-To 100 eV, {beta} Almost-Equal-To 30%). In contrast to the predictions of MHD-theory, stability was observed only for

  8. The influence of ego depletion on sprint start performance in athletes without track and field experience.

    Science.gov (United States)

    Englert, Chris; Persaud, Brittany N; Oudejans, Raôul R D; Bertrams, Alex

    2015-01-01

    We tested the assumption that ego depletion would affect the sprint start in a sample of N = 38 athletes without track and field experience in an experiment by applying a mixed between- (depletion vs. non-depletion) within- (T1: before manipulation of ego depletion vs. T2: after manipulation of ego depletion) subjects design. We assumed that ego depletion would increase the possibility for a false start, as regulating the impulse to initiate the sprinting movement too soon before the starting signal requires self-control. In line with our assumption, we found a significant interaction as there was only a significant increase in the number of false starts from T1 to T2 for the depletion group while this was not the case for the non-depletion group. We conclude that ego depletion has a detrimental influence on the sprint start in athletes without track and field experience.

  9. Contributions of meaningful experiences gatherings to artistic education field

    Directory of Open Access Journals (Sweden)

    Bernardo Bustamante Cardona

    2012-06-01

    Full Text Available This article shows a theoretical approach to and a description of some contributions of a work of transformation of educational and sociocultural reality carried out by a group of people and institutions, among which are San Buenaventura University, Antioquia Museum, Ediarte Inc. and Antioquia University. Such intervention aims at contributing to the improvement of Artistic Education quality in Antioquia and the nation. In order to understand the significance of these Gatherings, a short historical framework is explained in which global and regional processes of academic activities having an impact on the structure of the Artistic Education field are pointed out. Likewise, some perspectives in the definition of artistic education are tackled and then a definition of Pierre Bourdieu´s concept of fieldis presented. Therefore, Meaningful Experiences Gatherings in Artistic Education (MEGAE are presented and the three first gatherings are described. Finally, it is shown the panorama of the contributions of the gatherings both in the theoretical formulation and relational structure of the field.

  10. Design experiences for medical irradiation field at the musashi reactor

    International Nuclear Information System (INIS)

    Aizawa, Otohiko

    1994-01-01

    The design of the medical irradiation field at the Musashi reactor was carried out from 1974 to 1975, about 20 years ago. Various numerical analyses have been carried out recently, and it is astonishing to find out that the performance close to the optimum as a 100 kW reactor has been obtained. The reason for this is that the design was carried out by dividing into the stationary part and the moving part, and as for the moving part, the structure was determined by repeating trial and error and experiments. In this paper, the comparison of the analysis carried out later with the experimental data and the change of the absorbed dose at the time of medical irradiation accompanying the change of neutron energy spectra are reported. As the characteristics of the medical irradiation field at the Musashi reactor, the neutron energy spectra and the absorbed dose and mean medical irradiation time are shown. As the problems in boron neutron capture therapy, the neutron fluence required for the therapy, the way of thinking on background dose, and the problem of determining the irradiation time are discussed. The features of epithermal neutron beam are explained. (K.I.)

  11. ARM Cloud-Aerosol-Precipitation Experiment (ACAPEX) Field Campaign Report

    Energy Technology Data Exchange (ETDEWEB)

    Leung, L Ruby [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-03-01

    The U.S. Department of Energy (DOE)’s Atmospheric Radiation Measurement (ARM) Climate Research Facility’s ARM Cloud-Aerosol-Precipitation Experiment (ACAPEX) field campaign contributes to CalWater 2015, a multi-agency field campaign that aims to improve understanding of atmospheric rivers and aerosol sources and transport that influence cloud and precipitation processes. The ultimate goal is to reduce uncertainties in weather predictions and climate projections of droughts and floods in California. With the DOE G-1 aircraft and ARM Mobile Facility 2 (AMF2) well equipped for making aerosol and cloud measurements, ACAPEX focuses specifically on understanding how aerosols from local pollution and long-range transport affect the amount and phase of precipitation associated with atmospheric rivers. ACAPEX took place between January 12, 2015 and March 8, 2015 as part of CalWater 2015, which included four aircraft (DOE G-1, National Oceanic and Atmospheric Administration [NOAA] G-IV and P-3, and National Aeronautics and Space Administration [NASA] ER-2), the NOAA research ship Ron Brown, carrying onboard the AMF2, National Science Foundation (NSF)-sponsored aerosol and precipitation measurements at Bodega Bay, and the California Department of Water Resources extreme precipitation network.

  12. Experiments in robotic sensorimotor control during grasp

    International Nuclear Information System (INIS)

    Stansfield, S.A.

    1993-01-01

    A series of experiments is presented, using a robot manipulator, which attempt to reproduce human sensorimotor control during grasping. The work utilizes a multifingered, dexterous robot hand equipped with a fingertip force sensor to explore dynamic grasp force adjustment during manipulation. The work is primarily concerned with the relationship between the weight of an object and the grasp force required to lift it. Too weak a grasp is unstable and the object will slip from the hand. Too strong a grasp may damage the object and/or the manipulator. An algorithm is presented which reproduces observed human behavior during grasp-and-lift tasks. The algorithm uses tactile information from the sensor to dynamically adjust the grasp force during lift. It is assumed that there is no a priori knowledge about the object to be manipulated. The effects of different arm/hand postures and object surfaces is explored. Finally, the use of sensory data to detect unexpected object motion and to signal transitions between manipulation phases--with the coincident triggering of new motor programs--is investigated

  13. No Margin, No Mission? A Field Experiment on Incentives for Public Services Delivery

    OpenAIRE

    Ashraf, Nava; Bandiera, Oriana; Jack, Kelsey

    2014-01-01

    A substantial body of research investigates the effect of pay for performance in firms, yet less is known about the effect of non-financial rewards, especially in organizations that hire individuals to perform tasks with positive social spillovers. We conduct a field experiment in which agents recruited by a public health organization to sell condoms are randomly allocated to four groups. Agents in the control group are hired as volunteers, whereas agents in the three treatment groups receive...

  14. Pyranometer offsets triggered by ambient meteorology: insights from laboratory and field experiments

    OpenAIRE

    S. M. Oswald; H. Pietsch; D. J. Baumgartner; P. Weihs; H. E. Rieder

    2017-01-01

    This study investigates effects of ambient meteorology on the accuracy of radiation measurements performed with pyranometers contained in various heating/ventilation systems (HV-systems). It focuses particularly on instrument offsets observed following precipitation events. To quantify pyranometer responses to precipitation, a series of controlled laboratory experiments as well as two targeted field campaigns were performed in 2016. The results indicate that precipitation (as simulated by spr...

  15. No Margin, no Mission? A Field Experiment on Incentives for public service delivery

    OpenAIRE

    Nava Ashraf; Oriana Bandiera; Kelsey Jack

    2012-01-01

    A substantial body of research investigates the design of incentives in firms, yet less is known about incentives in organizations that hire individuals to perform tasks with positive social spillovers. We conduct a field experiment in which agents hired by a public health organization are randomly allocated to four groups. Agents in the control group receive a standard volunteer contract often offered for this type of task, whereas agents in the three treatment groups receive small financial...

  16. No margin, no mission? A Field Experiment on Incentives for Pro-Social Tasks

    OpenAIRE

    Ashraf, Nava; Bandiera, Oriana; Jack, Kelsey

    2012-01-01

    A substantial body of research investigates the design of incentives in firms, yet less is known about incentives in organizations that hire individuals to perform tasks with positive social spillovers. We conduct a field experiment in which agents hired by a public health organization are randomly allocated to four groups. Agents in the control group receive a standard volunteer contract often offered for this type of task, whereas agents in the three treatment groups receive small financial...

  17. Preparing beginning reading teachers: An experimental comparison of initial early literacy field experiences

    OpenAIRE

    Al Otaiba, Stephanie; Lake, Vickie E.; Greulich, Luana; Folsom, Jessica S.; Guidry, Lisa

    2012-01-01

    This randomized-control trial examined the learning of preservice teachers taking an initial Early Literacy course in an early childhood education program and of the kindergarten or first grade students they tutored in their field experience. Preservice teachers were randomly assigned to one of two tutoring programs: Book Buddies and Tutor Assisted Intensive Learning Strategies (TAILS), which provided identical meaning-focused instruction (shared book reading), but differed ...

  18. Hidden Benefits of Reward : A Field Experiment on Motivation and Monetary Incentives

    OpenAIRE

    Kvaløy, Ola; Nieken, Petra; Schöttner, Anja

    2013-01-01

    We conducted a field experiment in a controlled work environment to investigate the effect of motivational talk and its interaction with monetary incentives. We find that motivational talk significantly improves performance only when accompanied by performance pay. Moreover, performance pay slightly reduces performance unless it is accompanied by motivational talk. These effects also carry over to the quality of work. Performance pay alone leads to more mistakes. Adding motivational talk make...

  19. The importance of the toroidal magnetic field for the feasibility of a tokamak burning plasma experiment

    International Nuclear Information System (INIS)

    Mazzucato, E.

    2000-01-01

    The next step in the demonstration of the scientific feasibility of a tokamak fusion reactor is a DT burning plasma experiment for the study and control of self-heated plasmas. In this paper, the authors examine the role of the toroidal magnetic field on the confinement of a tokamak plasma in the ELMy H-mode regime--the operational regime foreseen for ITER

  20. Controller tuning of district heating networks using experiment design techniques

    International Nuclear Information System (INIS)

    Dobos, Laszlo; Abonyi, Janos

    2011-01-01

    There are various governmental policies aimed at reducing the dependence on fossil fuels for space heating and the reduction in its associated emission of greenhouse gases. DHNs (District heating networks) could provide an efficient method for house and space heating by utilizing residual industrial waste heat. In such systems, heat is produced and/or thermally upgraded in a central plant and then distributed to the end users through a pipeline network. The control strategies of these networks are rather difficult thanks to the non-linearity of the system and the strong interconnection between the controlled variables. That is why a NMPC (non-linear model predictive controller) could be applied to be able to fulfill the heat demand of the consumers. The main objective of this paper is to propose a tuning method for the applied NMPC to fulfill the control goal as soon as possible. The performance of the controller is characterized by an economic cost function based on pre-defined operation ranges. A methodology from the field of experiment design is applied to tune the model predictive controller to reach the best performance. The efficiency of the proposed methodology is proven throughout a case study of a simulated NMPC controlled DHN. -- Highlights: → To improve the energetic and economic efficiency of a DHN an appropriate control system is necessary. → The time consumption of transitions can be shortened with the proper control system. → A NLMPC is proposed as control system. → The NLMPC is tuned by utilization of simplex methodology, using an economic oriented cost function. → The proposed NLMPC needs a detailed model of the DHN based on the physical description.

  1. A novel mathematical model for controllable near-field electrospinning

    International Nuclear Information System (INIS)

    Ru, Changhai; Chen, Jie; Shao, Zhushuai; Pang, Ming; Luo, Jun

    2014-01-01

    Near-field electrospinning (NFES) had better controllability than conventional electrospinning. However, due to the lack of guidance of theoretical model, precise deposition of micro/nano fibers could only accomplished by experience. To analyze the behavior of charged jet in NFES using mathematical model, the momentum balance equation was simplified and a new expression between jet cross-sectional radius and axial position was derived. Using this new expression and mass conservation equation, expressions for jet cross-sectional radius and velocity were derived in terms of axial position and initial jet acceleration in the form of exponential functions. Based on Slender-body theory and Giesekus model, a quadratic equation for initial jet acceleration was acquired. With the proposed model, it was able to accurately predict the diameter and velocity of polymer fibers in NFES, and mathematical analysis rather than experimental methods could be applied to study the effects of the process parameters in NFES. Moreover, the movement velocity of the collector stage can be regulated by mathematical model rather than experience. Therefore, the model proposed in this paper had important guiding significance to precise deposition of polymer fibers

  2. A novel mathematical model for controllable near-field electrospinning

    Science.gov (United States)

    Ru, Changhai; Chen, Jie; Shao, Zhushuai; Pang, Ming; Luo, Jun

    2014-01-01

    Near-field electrospinning (NFES) had better controllability than conventional electrospinning. However, due to the lack of guidance of theoretical model, precise deposition of micro/nano fibers could only accomplished by experience. To analyze the behavior of charged jet in NFES using mathematical model, the momentum balance equation was simplified and a new expression between jet cross-sectional radius and axial position was derived. Using this new expression and mass conservation equation, expressions for jet cross-sectional radius and velocity were derived in terms of axial position and initial jet acceleration in the form of exponential functions. Based on Slender-body theory and Giesekus model, a quadratic equation for initial jet acceleration was acquired. With the proposed model, it was able to accurately predict the diameter and velocity of polymer fibers in NFES, and mathematical analysis rather than experimental methods could be applied to study the effects of the process parameters in NFES. Moreover, the movement velocity of the collector stage can be regulated by mathematical model rather than experience. Therefore, the model proposed in this paper had important guiding significance to precise deposition of polymer fibers.

  3. A novel mathematical model for controllable near-field electrospinning

    Energy Technology Data Exchange (ETDEWEB)

    Ru, Changhai, E-mail: rchhai@gmail.com, E-mail: luojun@shu.edu.cn [College of Automation, Harbin Engineering University, Harbin 150001 (China); Robotics and Microsystems Center, Soochow University, Suzhou 215021 (China); Chen, Jie; Shao, Zhushuai [Robotics and Microsystems Center, Soochow University, Suzhou 215021 (China); Pang, Ming [College of Automation, Harbin Engineering University, Harbin 150001 (China); Luo, Jun, E-mail: rchhai@gmail.com, E-mail: luojun@shu.edu.cn [School of Mechatronics Engineering and Automation, Shanghai University, Shanghai 200072 (China)

    2014-01-15

    Near-field electrospinning (NFES) had better controllability than conventional electrospinning. However, due to the lack of guidance of theoretical model, precise deposition of micro/nano fibers could only accomplished by experience. To analyze the behavior of charged jet in NFES using mathematical model, the momentum balance equation was simplified and a new expression between jet cross-sectional radius and axial position was derived. Using this new expression and mass conservation equation, expressions for jet cross-sectional radius and velocity were derived in terms of axial position and initial jet acceleration in the form of exponential functions. Based on Slender-body theory and Giesekus model, a quadratic equation for initial jet acceleration was acquired. With the proposed model, it was able to accurately predict the diameter and velocity of polymer fibers in NFES, and mathematical analysis rather than experimental methods could be applied to study the effects of the process parameters in NFES. Moreover, the movement velocity of the collector stage can be regulated by mathematical model rather than experience. Therefore, the model proposed in this paper had important guiding significance to precise deposition of polymer fibers.

  4. HAMMLAB 1999 experimental control room: design - design rationale - experiences

    International Nuclear Information System (INIS)

    Foerdestroemmen, N. T.; Meyer, B. D.; Saarni, R.

    1999-01-01

    A presentation of HAMMLAB 1999 experimental control room, and the accumulated experiences gathered in the areas of design and design rationale as well as user experiences. It is concluded that HAMMLAB 1999 experimental control room is a realistic, compact and efficient control room well suited as an Advanced NPP Control Room (ml)

  5. Measuring microbial fitness in a field reciprocal transplant experiment.

    Science.gov (United States)

    Boynton, Primrose J; Stelkens, Rike; Kowallik, Vienna; Greig, Duncan

    2017-05-01

    Microbial fitness is easy to measure in the laboratory, but difficult to measure in the field. Laboratory fitness assays make use of controlled conditions and genetically modified organisms, neither of which are available in the field. Among other applications, fitness assays can help researchers detect adaptation to different habitats or locations. We designed a competitive fitness assay to detect adaptation of Saccharomyces paradoxus isolates to the habitat they were isolated from (oak or larch leaf litter). The assay accurately measures relative fitness by tracking genotype frequency changes in the field using digital droplet PCR (DDPCR). We expected locally adapted S. paradoxus strains to increase in frequency over time when growing on the leaf litter type from which they were isolated. The DDPCR assay successfully detected fitness differences among S. paradoxus strains, but did not find a tendency for strains to be adapted to the habitat they were isolated from. Instead, we found that the natural alleles of the hexose transport gene we used to distinguish S. paradoxus strains had significant effects on fitness. The origin of a strain also affected its fitness: strains isolated from oak litter were generally fitter than strains from larch litter. Our results suggest that dispersal limitation and genetic drift shape S. paradoxus populations in the forest more than local selection does, although further research is needed to confirm this. Tracking genotype frequency changes using DDPCR is a practical and accurate microbial fitness assay for natural environments. © 2016 The Authors. Molecular Ecology Resources Published by John Wiley & Sons Ltd.

  6. Fusion Performance of High Magnetic Field Expe-riments

    Science.gov (United States)

    Airoldi, A.; Cenacchi, G.; Coppi, B.

    1997-11-01

    High magnetic field machines have the characteristic of operating well within the usual limitations known as density and beta limits. This feature is highlighted in the Ignitor concept thanks to its reference field of up to 13 T on the magnetic axis and its high current densities. The two reference scenarios with plasma currents of 12 MA and 11 MA respectively, are discussed. The ramp time is 4 sec for both scenarios, whereas the following programmed time dependence of the current is different. The results of an extensive series of numerical simulations using an appropriate version of the 1+1/2D JETTO transport code show that in any case optimal fusion performances are reacheable without needing enhancement over the values of the energy replacement time predicted by the most pessimistic scalings (for the so-called L-mode regime). The density is the crucial parameter involved on the path to ignition that can be achieved provided the density rise is carefully programmed. The density profiles can be controlled by the proper use of the pellet injector that is included in the machine design.

  7. Field-reversed experiments (FRX) on compact toroids

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, W.T.; Linford, R.K.; Lipson, J.; Platts, D.A.; Sherwood, E.G.

    1981-11-01

    Equilibrium, stability, and confinement properties of compact toroids produced in field-reversed theta-pinch experiments (FRX) are reported. Two experimental facilities, FRX-A and FRX-B, have been used to study highly elongated compact toroid plasmas confined in a purely poloidal field geometry. Spatial scans and fill pressure scaling of the equilibrium plasma parameters are presented. Plasma conditions range from T/sub e/approx.150 eV, T/sub i/approx.800 eV, n/sub m/approx.1 x 10/sup 15/ cm/sup -3/ to T/sub e/approx.100 eV, T/sub i/approx.150 eV, n/sub m/approx.4 x 10/sup 15/ cm/sup -3/. Typical confined plasma dimensions are: major radius Rapprox.4 cm, minor radius aapprox.2 cm, and total length 35--50 cm. The plasma configuration remains in a stable equilibrium for up to 50 ..mu..sec followed by the destructive n = 2 rotational instability. The stable period prior to the onset of the rotational mode is up to one hundred times greater than characteristic Alfven transit times of the plasma. This stable period increases and the mode growth rate decreases with increased a/rho/sub i/ (where rho/sub i/ is the ion gyroradius). Agreement of experimental and theoretical mode frequencies for the instability is observed. Preferential particle loss has been proposed as a likely cause of rotation. The particle inventory at the onset of the instability is consistent with this hypothesis. The particle loss rate is also consistent with the predicted anomalous transport near the separatrix. Contributions to rotational instability from diffusion, end-shorting, equipartition, and compression are also discussed.

  8. Field-reversed experiments (FRX) on compact toroids

    International Nuclear Information System (INIS)

    Armstrong, W.T.; Linford, R.K.; Lipson, J.; Platts, D.A.; Sherwood, E.G.

    1981-01-01

    Equilibrium, stability, and confinement properties of compact toroids produced in field-reversed theta-pinch experiments (FRX) are reported. Two experimental facilities, FRX-A and FRX-B, have been used to study highly elongated compact toroid plasmas confined in a purely poloidal field geometry. Spatial scans and fill pressure scaling of the equilibrium plasma parameters are presented. Plasma conditions range from T/sub e/approx.150 eV, T/sub i/approx.800 eV, n/sub m/approx.1 x 10 15 cm -3 to T/sub e/approx.100 eV, T/sub i/approx.150 eV, n/sub m/approx.4 x 10 15 cm -3 . Typical confined plasma dimensions are: major radius Rapprox.4 cm, minor radius aapprox.2 cm, and total length 35--50 cm. The plasma configuration remains in a stable equilibrium for up to 50 μsec followed by the destructive n = 2 rotational instability. The stable period prior to the onset of the rotational mode is up to one hundred times greater than characteristic Alfven transit times of the plasma. This stable period increases and the mode growth rate decreases with increased a/rho/sub i/ (where rho/sub i/ is the ion gyroradius). Agreement of experimental and theoretical mode frequencies for the instability is observed. Preferential particle loss has been proposed as a likely cause of rotation. The particle inventory at the onset of the instability is consistent with this hypothesis. The particle loss rate is also consistent with the predicted anomalous transport near the separatrix. Contributions to rotational instability from diffusion, end-shorting, equipartition, and compression are also discussed

  9. Research note : field control of asphalt concrete paving mixtures.

    Science.gov (United States)

    1995-01-01

    The goal of this study was to develop information and evaluate new methods for controlling quality of the AC mixture in the mat. Specifically, this research project evaluated a gyratory compactor in the field laboratory to determine mix quality. Spec...

  10. Dynamic Artificial Potential Fields for Autonomous Camera Control

    DEFF Research Database (Denmark)

    Burelli, Paolo; Jhala, Arnav Harish

    2009-01-01

    the implementation and evaluation of Artificial Potential Fields for automatic camera placement. We first describe the re- casting of the frame composition problem as a solution to a two particles suspended in an Artificial Potential Field. We demonstrate the application of this technique to control both camera...

  11. Physics experiments with Nintendo Wii controllers

    Science.gov (United States)

    Wheeler, Martyn D.

    2011-01-01

    This article provides a detailed description of the use of Nintendo Wii game controllers in physics demonstrations. The main features of the controller relevant to physics are outlined and the procedure for communicating with a PC is described. A piece of software written by the author is applied to gathering data from a controller suspended from a spring undergoing simple harmonic motion, a pair of controllers mounted on colliding gliders on a linear air track, and a person jumping from a balance board.

  12. Physics Experiments with Nintendo Wii Controllers

    Science.gov (United States)

    Wheeler, Martyn D.

    2011-01-01

    This article provides a detailed description of the use of Nintendo Wii game controllers in physics demonstrations. The main features of the controller relevant to physics are outlined and the procedure for communicating with a PC is described. A piece of software written by the author is applied to gathering data from a controller suspended from…

  13. Field Experiment on Soaking Characteristics of Collapsible Loess

    Directory of Open Access Journals (Sweden)

    Zhichao Wang

    2017-01-01

    Full Text Available In collapsible loess area, migration of soil moisture often causes the temporal discontinuity and spatial nonuniformity of collapsibility, which leads to great damage for infrastructures. Therefore, the research on water infiltration is the key to solving the problem of collapsibility. The aim of this paper is to investigate the spatiotemporal evolution of infiltration characteristics of collapsible loess. A field soaking experiment was conducted on collapsible loess in western China, in which a soaking pool with diameter of 15 m was built. Time-Domain-Reflectometry (TDR system and soil sampling were employed to measure the water content within the depth of 12 m. Then the saturation isograms were drawn for visualization of the process of infiltration. Also, a pilot tunnel was excavated to investigate how the free face can affect the infiltration behaviors. The experimental results revealed the characteristics of infiltration in both horizontal and vertical directions. Moreover, the response of free face on infiltration behaviors was also found. These findings of research could provide the data for the infiltration laws of unsaturated loess and thereby provide the basis for integrated treatment of collapsible loess.

  14. Natural selection on immune defense: A field experiment.

    Science.gov (United States)

    Langeloh, Laura; Behrmann-Godel, Jasminca; Seppälä, Otto

    2017-02-01

    Predicting the evolution of phenotypic traits requires an understanding of natural selection on them. Despite its indispensability in the fight against parasites, selection on host immune defense has remained understudied. Theory predicts immune traits to be under stabilizing selection due to associated trade-offs with other fitness-related traits. Empirical studies, however, report mainly positive directional selection. This discrepancy could be caused by low phenotypic variation in the examined individuals and/or variation in host resource level that confounds trade-offs in empirical studies. In a field experiment where we maintained Lymnaea stagnalis snails individually in cages in a lake, we investigated phenotypic selection on two immune defense traits, phenoloxidase (PO)-like activity and antibacterial activity, in hemolymph. We used a diverse laboratory population and manipulated snail resource level by limiting their food supply. For six weeks, we followed immune activity, growth, and two fitness components, survival and fecundity of snails. We found that PO-like activity and growth were under stabilizing selection, while antibacterial activity was under positive directional selection. Selection on immune traits was mainly driven by variation in survival. The form of selection on immune defense apparently depends on the particular trait, possibly due to its importance for countering the present parasite community. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  15. Chaos in reversed-field-pinch plasma simulation and experiment

    International Nuclear Information System (INIS)

    Watts, C.; Newman, D.E.; Sprott, J.C.

    1994-01-01

    We investigate the possibility that chaos and simple determinism are governing the dynamics of reversed-field-pinch (RFP) plasmas using data from both numerical simulations and experiment. A large repertoire of nonlinear-analysis techniques is used to identify low-dimensional chaos. These tools include phase portraits and Poincare sections, correlation dimension, the spectrum of Lyapunov exponents, and short-term predictability. In addition, nonlinear-noise-reduction techniques are applied to the experimental data in an attempt to extract any underlying deterministic dynamics. Two model systems are used to simulate the plasma dynamics. These are the DEBS computer code, which models global RFP dynamics, and the dissipative trapped-electron-mode model, which models drift-wave turbulence. Data from both simulations show strong indications of low-dimensional chaos and simple determinism. Experimental data were obtained from the Madison Symmetric Torus RFP and consist of a wide array of both global and local diagnostic signals. None of the signals shows any indication of low-dimensional chaos or other simple determinism. Moreover, most of the analysis tools indicate that the experimental system is very high dimensional with properties similar to noise. Nonlinear noise reduction is unsuccessful at extracting an underlying deterministic system

  16. Bio-mechanical removing of contaminated soils: a field experiment

    International Nuclear Information System (INIS)

    Jouve, A.; Maubert, H.; Schulte, E.

    1992-01-01

    If, in spite of safety precautions, a major nuclear accident would occur, countermeasures should be taken to attenuate the impact of radioactive deposits. The European RESSAC program (REhabilitation of Soils and Surfaces after an ACcident) aims at studying actions for normal life return in contaminated zones. One of them, called the Decontaminating Vegetal Network (D.V.N.) associates the biological action of turfing plants, producing a dense root-network capable to trap the top contaminated soil particles, and the mechanical efficiency of a turf harvester which can remove only 1 cm of soil. This performance, not associated with other techniques of soil removal such as scrapers or bulldozers, leads to minimize the waste production. The D.V.N is a vegetal cover spread over the contaminated soil, using the hydro-seeding technique. The growing plants are forming a pleasant lawn which may have a positive impact on the public opinion compared to techniques using bitumen mixtures to cover the soil. Field experiments involving labelling solutions of stable molybdenum salts simulating the contamination of the soil have shown that this technique can be applied as well on homogeneous cultivated soil surfaces as on roughly ploughed soils. 4 refs., 3 figs., 2 tabs

  17. Mismo field experiment in the equatorial Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Masumoto, Y.; Kuroda, Y.; Katsumata, M.; Mizuno, K.; Takayabu, Y.N.; Yoshizaki, M.; Shareef, A.; Fujiyoshi, Y.; McPhaden, M.J.; Murty, V.S.N.; Shirooka, R; Yasunaga, K.; Yamada, H.; Sato, N.; Ushiyama, T.; Moteki, Q.; Seiki, A.; Fujita, M.; Ando, K.; Hase, H.; Ueki, I; Horii, T.; Yokoyama, C.; Miyakawa, T.

    MISMO FIELD EXPERIMENT IN THE EQUATORIAL INDIAN OCEAN * b y Ku n i o yo n e y a m a , yu K i o ma s u m o t o , yo s h i f u m i Ku r o d a , ma s a K i Ka t s u m a t a , Ke i s u K e mi z u n o , yu K a r i n. ta K a y a b u , ma s a n o r i... yo s h i z a K i , al i sh a r e e f, ya s u s h i fu j i y o s h i , mi c h a e l j. mcPh a d e n , V. s. n. mu r t y , ry u i c h i sh i r o o K a , Ka z u a K i ya s u n a g a , hi r o y u K i ya m a d a , na o K i sa t o , to m o K i us...

  18. ARM West Antarctic Radiation Experiment (AWARE) Field Campaign Report

    Energy Technology Data Exchange (ETDEWEB)

    Lubin, Daniel [Univ. of California, San Diego, CA (United States). Scripps Inst. of Oceanography; Bromwich, David H [Ohio State University; Vogelmann, Andrew M [Brookhaven National Lab. (BNL), Upton, NY (United States); Verlinde, Johannes [Pennsylvania State Univ., University Park, PA (United States); Russell, Lynn M [Univ. of California, San Diego, CA (United States). Scripps Inst. of Oceanography

    2017-09-15

    The U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) West Antarctic Radiation Experiment (AWARE) is the most technologically advanced atmospheric and climate science campaign yet fielded in Antarctica. AWARE was motivated be recent concern about the impact of cryospheric mass loss on global sea level rise. Specifically, the West Antarctic Ice Sheet (WAIS) is now the second largest contributor to rising sea level, after the Greenland Ice Sheet. As steadily warming ocean water erodes the grounding lines of WAIS components where they meet the Amundsen and Bellingshausen Seas, the retreating grounding lines moving inland and downslope on the underlying terrain imply mechanical instability of the entire WAIS. There is evidence that this point of instability may have already been reached, perhaps signifying more rapid loss of WAIS ice mass. At the same time, the mechanical support provided by adjacent ice shelves, and also the fundamental stability of exposed ice cliffs at the ice sheet grounding lines, will be adversely impacted by a warming atmosphere that causes more frequent episodes of surface melting. The surface meltwater damages the ice shelves and ice cliffs through hydrofracturing. With the increasing concern regarding these rapid cryospheric changes, AWARE was motivated by the need to (a) diagnose the surface energy balance in West Antarctica as related to both summer season climatology and potential surface melting, and (b) improve global climate model (GCM) performance over Antarctica, such that future cryospheric projections can be more reliable.

  19. Idaho field experiment 1981. Volume 2: measurement data

    Energy Technology Data Exchange (ETDEWEB)

    Start, G E; Sagendorf, J F; Ackermann, G R; Cate, J H; Hukari, N F; Dickson, C R

    1984-04-01

    The 1981 Idaho Field Experiment was conducted in southeastern Idaho over the upper Snake River Plain. Nine test-day case studies were conducted between July 15 and 30, 1981. Releases of SF/sub 6/ gaseous tracer were made for 8-hour periods from 46m above ground. Tracer was sampled hourly, for 12 sequential hours, at about 100 locations within an area 24km square. Also, a single total integrated sample of about 30 hours duration was collected at approximately 100 sites within an area 48 by 72km square (using 6km spacings). Extensive tower profiles of meteorology at the release point were collected. RAWINSONDES, RABALS and PIBALS were collected at 3 to 5 sites. Horizontal, low-altitude winds were monitored using the INEL MESONET. SF/sub 6/ tracer plume releases were marked with co-located oil fog releases and bi-hourly sequential launches of tetroon pairs. Aerial LIDAR observations of the oil fog plume and airborne samples of SF/sub 6/ were collected. High altitude aerial photographs of daytime plumes were collected. Volume II lists the data in tabular form or cites the special supplemental reports by other participating contractors. While the primary user file and the data archive are maintained on 9 track/1600 cpi magnetic tapes, listings of the individual values are provided for the user who either cannot utilize the tapes or wishes to preview the data. The accuracies and quality of these data are described.

  20. Perspectives on global nursing leadership: international experiences from the field.

    Science.gov (United States)

    Buckner, E B; Anderson, D J; Garzon, N; Hafsteinsdóttir, T B; Lai, C K Y; Roshan, R

    2014-12-01

    Nursing leaders from six countries engaged in a year-long discussion on global leadership development. The purpose of these dialogues was to strengthen individual and collective capacity as nursing leaders in a global society. Field experiences in practice and education were shared. Perspectives on global leadership can strengthen nurses' contributions to practice, workplace and policy issues worldwide. Transformational leadership empowers nurses' increasing confidence. Mentoring is needed to stimulate leadership development but this is lacking in many settings where nurses practice, teach and influence policy. Organizations with global mission provide opportunity for nurses' professional growth in leadership through international dialogues. Dialogues among participants were held monthly by conference calls or videoconferences. Example stories from each participant illustrated nursing leadership in action. From these exemplars, concepts were chosen to create a framework. Emerging perspectives and leadership themes represented all contexts of practice, education, research and policy. The cultural context of each country was reflected in the examples. Themes emerged that crossed global regions and countries. Themes were creativity, change, collaboration, community, context and courage. Relationships initially formed in professional organizations can be extended to intentionally facilitate global nursing leadership development. Exemplars from the dialogues demonstrated nursing leadership in health policy development within each cultural context. Recommendations are given for infrastructure development in organizations to enhance future collaborations. © 2014 International Council of Nurses.

  1. Test plan for FY-94 digface characterization field experiments

    International Nuclear Information System (INIS)

    Josten, N.E.; Roybal, L.G.

    1994-08-01

    The digface characterization concept has been under development at the Idaho National Engineering Laboratory (INEL) since fiscal year (FY) 1992 through the support of the Buried Waste Integrated Demonstration Program. A digface characterization system conducts continuous subsurface characterization simultaneously with retrieval of hazardous and radioactive waste from buried waste sites. The system deploys multiple sensors at the retrieval operation digface and collects data that provide a basis for detecting, locating, and classifying buried materials and hazardous conditions before they are disturbed by the retrieval equipment. This test plan describes ongoing efforts to test the digface characterization concept at the INEL's Cold Test Pit using a simplified prototype deployment apparatus and off-the-shelf sensors. FY-94 field experiments will explore problems in object detection and classification. Detection and classification of objects are fundamental to three of the four primary functions of digface characterization during overburden removal. This test plan establishes procedures for collecting and validating the digface characterization data sets. Analysis of these data will focus on testing and further developing analysis methods for object detection and classification during overburden removal

  2. Romanian Radiation Protection Training Experience in Medical Field

    International Nuclear Information System (INIS)

    Steliana Popescu, F.; Milu, C.; Naghi, E.; Calugareanu, L.; Stroe, F. M.

    2003-01-01

    Studies conducted by the Institute of Public Health Bucharest during the last years emphasised the need of appropriate radioprotection training in the medical field. With the assistance of the International Atomic Energy Agency in Vienna, the Pilot Centre on Clinical Radio pathology in the Institute of Public Health-Bucharest, provided, from 2000 a 7 modular courses (40 hours each), covering the basic topics of ionizing radiation, biological and physical dosimetry, effects of exposure to ionising radiation, radioprotection concepts, planning and medical response in case of a nuclear accident or radiological emergency. The courses are opened for all health specialists, especially for occupational health physicians, focusing on health surveillance of radiation workers and medical management of overexposed workers. Each module is followed up by an examination and credits. The multidisciplinary team of instructors was trained within several train-the-trainers courses, organised by IAEA. The paper discusses the evaluation of these 3 years experience in training and its feedback impact, the aim of the program being to develop a knowledge in the spirit of the new patterns of radiological protection, both for safety and communication with the public. (Author)

  3. Effective media models for unsaturated fractured rock: A field experiment

    International Nuclear Information System (INIS)

    Nicholl, M.J.; Glass, R.J.

    1995-01-01

    A thick unsaturated rock mass at Yucca Mountain is currently under consideration as a potential repository site for disposal of high level radioactive waste. In accordance with standard industry and scientific practices, abstract numerical models will be used to evaluate the potential for radionuclide release through the groundwater system. At this time, currently available conceptual models used to develop effective media properties are based primarily on simplistic considerations. The work presented here is part of an integrated effort to develop effective media models at the intermediate block scale (approximately 8-125m) through a combination of physical observations, numerical simulations and theoretical considerations. A multi-purpose field experiment designed and conducted as part of this integrated effort is described. Specific goals of this experimental investigation were to: (1) obtain fracture network data from Topopah Spring Tuff for use in block scale simulations; (2) identity positions of the network conducting flow under three different boundary conditions; (3) visualize preferential flow paths and small-scale flow structures; (4) collect samples for subsequent hydraulic testing and use in block-scale simulations; and (5) demonstrate the ability of Electrical Resistance Tomography (ERT) to delineate fluid distribution within fractured rock

  4. General distributed control system for fusion experiments

    International Nuclear Information System (INIS)

    Klingner, P.L.; Levings, S.J.; Wilkins, R.W.

    1986-01-01

    A general control system using distributed LSI-11 microprocessors is being developed. Common software residues in each LSI-11 and is tailored to an application by control specifications downloaded from a host computer. The microprocessors, their control interfaces, and the micro-to-host communications are CAMAC based. The host computer also supports an operator interface, coordination of multiple microprocessors, and utilities to create and maintain the control specifications. Typical applications include monitoring safety interlocks as well as controlling vacuum systems, high voltage charging systems, and diagnostics

  5. Visual field changes after cataract extraction: the AGIS experience.

    Science.gov (United States)

    Koucheki, Behrooz; Nouri-Mahdavi, Kouros; Patel, Gitane; Gaasterland, Douglas; Caprioli, Joseph

    2004-12-01

    To test the hypothesis that cataract extraction in glaucomatous eyes improves overall sensitivity of visual function without affecting the size or depth of glaucomatous scotomas. Experimental study with no control group. One hundred fifty-eight eyes (of 140 patients) from the Advanced Glaucoma Intervention Study with at least two reliable visual fields within a year both before and after cataract surgery were included. Average mean deviation (MD), pattern standard deviation (PSD), and corrected pattern standard deviation (CPSD) were compared before and after cataract extraction. To evaluate changes in scotoma size, the number of abnormal points (P < .05) on the pattern deviation plot was compared before and after surgery. We described an index ("scotoma depth index") to investigate changes of scotoma depth after surgery. Mean values for MD, PSD, and CPSD were -13.2, 6.4, and 5.9 dB before and -11.9, 6.8, and 6.2 dB after cataract surgery (P < or = .001 for all comparisons). Mean (+/- SD) number of abnormal points on pattern deviation plot was 26.7 +/- 9.4 and 27.5 +/- 9.0 before and after cataract surgery, respectively (P = .02). Scotoma depth index did not change after cataract extraction (-19.3 vs -19.2 dB, P = .90). Cataract extraction caused generalized improvement of the visual field, which was most marked in eyes with less advanced glaucomatous damage. Although the enlargement of scotomas was statistically significant, it was not clinically meaningful. No improvement of sensitivity was observed in the deepest part of the scotomas.

  6. EPIC Calibration/Validation Experiment Field Campaign Report

    Energy Technology Data Exchange (ETDEWEB)

    Koch, Steven E [National Severe Storm Laboratory/NOAA; Chilson, Phillip [University of Oklahoma; Argrow, Brian [University of Colorado

    2017-03-15

    A field exercise involving several different kinds of Unmanned Aerial Systems (UAS) and supporting instrumentation systems provided by DOE/ARM and NOAA/NSSL was conducted at the ARM SGP site in Lamont, Oklahoma on 29-30 October 2016. This campaign was part of a larger National Oceanic and Atmospheric Administration (NOAA) UAS Program Office program awarded to the National Severe Storms Laboratory (NSSL). named Environmental Profiling and Initiation of Convection (EPIC). The EPIC Field Campaign (Test and Calibration/Validation) proposed to ARM was a test or “dry-run” for a follow-up campaign to be requested for spring/summer 2017. The EPIC project addresses NOAA’s objective to “evaluate options for UAS profiling of the lower atmosphere with applications for severe weather.” The project goal is to demonstrate that fixed-wing and rotary-wing small UAS have the combined potential to provide a unique observing system capable of providing detailed profiles of temperature, moisture, and winds within the atmospheric boundary layer (ABL) to help determine the potential for severe weather development. Specific project objectives are: 1) to develop small UAS capable of acquiring needed wind and thermodynamic profiles and transects of the ABL using one fixed-wing UAS operating in tandem with two different fixed rotary-wing UAS pairs; 2) adapt and test miniaturized, high-precision, and fast-response atmospheric sensors with high accuracy in strong winds characteristic of the pre-convective ABL in Oklahoma; 3) conduct targeted short-duration experiments at the ARM Southern Great Plains site in northern Oklahoma concurrently with a second site to be chosen in “real-time” from the Oklahoma Mesonet in coordination with the (National Weather Service (NWS)-Norman Forecast Office; and 4) gain valuable experience in pursuit of NOAA’s goals for determining the value of airborne, mobile observing systems for monitoring rapidly evolving high-impact severe weather

  7. Field experiments on eyewitness identification: towards a better understanding of pitfalls and prospects.

    Science.gov (United States)

    Wells, Gary L

    2008-02-01

    The Illinois pilot program on lineup procedures has helped sharpen the focus on the types of controls that are needed in eyewitness field experiments and the limits that exist for interpreting outcome measures (rates of suspect and filler identifications). A widely-known limitation of field experiments is that, unlike simulated crime experiments, the guilt or innocence of the suspects is not easily known independently of the behavior of the eyewitnesses. Less well appreciated is that the rate of identification of lineup fillers, although clearly errors, can be a misleading measure if the filler identification rate is used to assess which of two or more lineup procedures is the better procedure. Several examples are used to illustrate that there are clearly improper procedures that would yield fewer identifications of fillers than would their proper counterparts. For example, biased lineup structure (e.g., using poorly matched fillers) as well as suggestive lineup procedures (that can result from non-blind administration of lineups) would reduce filler identification errors compared to unbiased and non-suggestive procedures. Hence, under many circumstances filler identification rates can be misleading indicators of preferred methods. Comparisons of lineup procedures in future field experiments will not be easily accepted in the absence of double-blind administration methods in all conditions plus true random assignment to conditions.

  8. Controlling three-dimensional vortices using multiple and moving external fields

    Science.gov (United States)

    Das, Nirmali Prabha; Dutta, Sumana

    2017-08-01

    Spirals or scroll wave activities in cardiac tissues are the cause of lethal arrhythmias. The external control of these waves is thus of prime interest to scientists and physicians. In this article, we demonstrate the spatial control of scroll waves by using external electric fields and thermal gradients in experiments with the Belousov-Zhabotinsky reaction. We show that a scroll ring can be made to trace cyclic trajectories under a rotating electric field. Application of a thermal gradient in addition to the electric field deflects the motion and changes the nature of the trajectory. Our experimental results are analyzed and corroborated by numerical simulations based on an excitable reaction diffusion model.

  9. Current profile control experiments in EXTRAP T2R

    Science.gov (United States)

    Brunsell, P.; Cecconello, M.; Drake, J.; Franz, P.; Malmberg, J. A.; Marrelli, L.; Martin, P.; Spizzo, G.

    2002-11-01

    EXTRAP T2R is a high aspect ratio (R=1.24 m, a = 0.183 m) reversed-field pinch device, characterised by a double, thin shell system. The simultaneous presence of many m=1, |n| > 11 tearing modes is responsible for a magnetic field turbulence, which is believed to produce the rather high energy and particle transport that is observed in this type of magnetic configuration. In this paper first results from current profile control experiments (PPCD) in a thin shell device are shown. When an edge poloidal electric field is transiently applied, an increase of the electron temperature and of the electron density is seen, which is consistent with an increase of the thermal content of the plasma. At the same time, the soft x-ray emission, measured with a newly installed miniaturised camera, shows a peaking of the profile in the core. Furthermore, the amplitudes of the m=1 tearing modes are reduced and and the rotation velocities increase during PPCD, which is also consistent with a reduction of magnetic turbulence and a heating of the plasma

  10. Chemical Weed Control in Saffron (Crocus sativus Fields

    Directory of Open Access Journals (Sweden)

    majid abbaspoor

    2018-01-01

    Full Text Available Introduction Saffron is derived from the stigmas of the saffron (Crocus sativus L. It is the world’s most expensive spice and has been widely used in many countries. It is also increasingly used for medicinal purposes. Weed control in this perennial, small and low growing crop, needs a lot of labor work. Chemical approach is one of the most effective methods for weed control in saffron. Currently, some herbicide options are available for applications in saffron. For example, satisfactory broadleaved weed control would be achieved by post-emergence application of metribuzin and ioxynil after harvesting saffron flowers. Application of glyphosate and/or 2, 4-D / 2, 4-DB are used to clean up the beds prior to the new season’s flowering and growth of saffron in New Zealand. The selective weed control of weeds in saffron has not been widely reported elsewhere but some in Iran. The choice of herbicide(s depends on the kind of weeds present. In some literatures metribuzin showed promising results for weed control in saffron fields. It is selectively used for control of annual grasses and numerous broad-leaved weeds. The objective of this study was the evaluation of the efficacy of 15 herbicides with different mode of actions, selected on the basis of dominant weed flora and previous studies, on weeds grown in saffron fields. Materials and Methods A field study was conducted to evaluate the efficacy of herbicides for weed control in saffron (Crocus sativus in Agricultural and Natural Resources Research and Education Center of Khorasan Razavi Province, Mashhad, in 2014-2015 growing season. The experiment was conducted in a completely randomized block design with three replications. Treatments were consisted of metsulfuron-methyl + sulfosulfuron (Total® at dose of 40 g ha-1, sulfosulfuron (Apirus® at dose of 26.6 g ha-1, oxadiazon (Ronestar® at dose of 2 l ha-1, oxyflurofen (Goal® at dose of 2 l ha-1, mesosulfuron + idosulfuron + diflufenican

  11. Calculations of transient fields in the Felix experiments at Argonne using null field integrated techniques

    International Nuclear Information System (INIS)

    Han, H.C.; Davey, K.R.; Turner, L.

    1985-08-01

    The transient eddy current problem is characteristically computationally intensive. The motivation for this research was to realize an efficient, accurate, solution technique involving small matrices via an eigenvalue approach. Such a technique is indeed realized and tested using the null field integral technique. Using smart (i.e., efficient, global) basis functions to represent unknowns in terms of a minimum number of unknowns, homogeneous eigenvectors and eigenvalues are first determined. The general excitatory response is then represented in terms of these eigenvalues/eigenvectors. Excellent results are obtained for the Argonne Felix cylinder experiments using a 4 x 4 matrix. Extension to the 3-D problem (short cylinder) is set up in terms of an 8 x 8 matrix

  12. Control of colloids with gravity, temperature gradients, and electric fields

    CERN Document Server

    Sullivan, M; Harrison, C; Austin, R H; Megens, M; Hollingsworth, A; Russel, W B; Cheng Zhen; Mason, T; Chaikin, P M

    2003-01-01

    We have used a variety of different applied fields to control the density, growth, and structure of colloidal crystals. Gravity exerts a body force proportional to the buoyant mass and in equilibrium produces a height-dependent concentration profile. A similar body force can be obtained with electric fields on charged particles (electrophoresis), a temperature gradient on all particles, or an electric field gradient on uncharged particles (dielectrophoresis). The last is particularly interesting since its magnitude and sign can be changed by tuning the applied frequency. We study these effects in bulk (making 'dielectrophoretic bottles' or traps), to control concentration profiles during nucleation and growth and near surfaces. We also study control of non-spherical and optically anisotropic particles with the light field from laser tweezers.

  13. Control of colloids with gravity, temperature gradients, and electric fields

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, Matt [Department of Physics, Princeton University, Princeton, NJ (United States); Zhao Kun [Department of Physics, Princeton University, Princeton, NJ (United States); Harrison, Christopher [Department of Physics, Princeton University, Princeton, NJ (United States); Austin, Robert H [Department of Physics, Princeton University, Princeton, NJ (United States); Megens, Mischa [Department of Physics, Princeton University, Princeton, NJ (United States); Hollingsworth, Andrew [Department of Chemical Engineering, Princeton University, Princeton, NJ (United States); Russel, William B [Department of Chemical Engineering, Princeton University, Princeton, NJ (United States); Cheng Zhengdong [ExxonMobil Research, Annandale, NJ (United States); Mason, Thomas [ExxonMobil Research, Annandale, NJ (United States); Chaikin, P M [Department of Physics, Princeton University, Princeton, NJ (United States)

    2003-01-15

    We have used a variety of different applied fields to control the density, growth, and structure of colloidal crystals. Gravity exerts a body force proportional to the buoyant mass and in equilibrium produces a height-dependent concentration profile. A similar body force can be obtained with electric fields on charged particles (electrophoresis), a temperature gradient on all particles, or an electric field gradient on uncharged particles (dielectrophoresis). The last is particularly interesting since its magnitude and sign can be changed by tuning the applied frequency. We study these effects in bulk (making 'dielectrophoretic bottles' or traps), to control concentration profiles during nucleation and growth and near surfaces. We also study control of non-spherical and optically anisotropic particles with the light field from laser tweezers.

  14. High magnetic field generation for laser-plasma experiments

    International Nuclear Information System (INIS)

    Pollock, B. B.; Froula, D. H.; Davis, P. F.; Ross, J. S.; Fulkerson, S.; Bower, J.; Satariano, J.; Price, D.; Krushelnick, K.; Glenzer, S. H.

    2006-01-01

    An electromagnetic solenoid was developed to study the effect of magnetic fields on electron thermal transport in laser plasmas. The solenoid, which is driven by a pulsed power system supplying 30 kJ, achieves magnetic fields of 13 T. The field strength was measured on the solenoid axis with a magnetic probe and optical Zeeman splitting. The measurements agree well with analytical estimates. A method for optimizing the solenoid design to achieve magnetic fields exceeding 20 T is presented

  15. Insights into organic carbon oxidation potential during fluvial transport from laboratory and field experiments

    Science.gov (United States)

    Scheingross, J. S.; Dellinger, M.; Eglinton, T. I.; Fuchs, M. C.; Golombek, N.; Hilton, R. G.; Hovius, N.; Lupker, M.; Repasch, M. N.; Sachse, D.; Turowski, J. M.; Vieth-Hillebrand, A.; Wittmann, H.

    2017-12-01

    Over geologic timescales, the exchange of organic carbon (OC) between the atmosphere, hydropshere, biosphere and geosphere can be a major control on atmospheric carbon dioxide concentrations. The carbon fluxes from the oxidation of rock-derived OC (a CO2 source) and erosion, transport, and burial of biospheric OC (a potential CO2 sink) during fluvial transit are approximately the same order of magnitude or larger than those from silicate weathering. Despite field data showing increasing oxidation of OC moving downstream in lowland rivers, it is unclear if losses occur primarily during active fluvial transport, where OC is in continual motion within an aerated river, or during periods of temporary storage in river floodplains which may be anoxic. The unknown location of OC oxidation (i.e., river vs. floodplain) limits our ability to mechanistically link geochemical and geomorphic processes which are required to develop models capable of predicting OC losses, constrain carbon budgets, and unravel links between climate, tectonics, and erosion. To fill this knowledge gap, we investigated OC oxidation in controlled laboratory experiments and a simplified field setting. We performed experiments in annular flumes that simulate fluvial transport without floodplain storage, allowing mixtures of OC-rich and siliciclastic sediment to be transported for distances of 1000 km. Preliminary experiments exploring both rock-derived and biospheric OC sources show minimal OC oxidation during active river transport, consistent with the idea that the majority of OC loss occurs during transient floodplain storage. These results are also consistent with new field data collected in the Rio Bermejo, Argentina, a lowland river traversing 800 km with no tributary inputs, where aged floodplain deposits have 3 to 10 times lower OC concentrations compared to modern river sediments. Together our field data and experiments support the hypothesis that oxidation of OC occurs primarily during

  16. Two-Dimensional Fuzzy Sliding Mode Control of a Field-Sensed Magnetic Suspension System

    Directory of Open Access Journals (Sweden)

    Jen-Hsing Li

    2014-01-01

    Full Text Available This paper presents the two-dimensional fuzzy sliding mode control of a field-sensed magnetic suspension system. The fuzzy rules include both the sliding manifold and its derivative. The fuzzy sliding mode control has advantages of the sliding mode control and the fuzzy control rules are minimized. Magnetic suspension systems are nonlinear and inherently unstable systems. The two-dimensional fuzzy sliding mode control can stabilize the nonlinear systems globally and attenuate chatter effectively. It is adequate to be applied to magnetic suspension systems. New design circuits of magnetic suspension systems are proposed in this paper. ARM Cortex-M3 microcontroller is utilized as a digital controller. The implemented driver, sensor, and control circuits are simpler, more inexpensive, and effective. This apparatus is satisfactory for engineering education. In the hands-on experiments, the proposed control scheme markedly improves performances of the field-sensed magnetic suspension system.

  17. Control of radial electric field in torus plasma

    International Nuclear Information System (INIS)

    Ida, K.; Idei, H.; Sanuki, H.

    1994-09-01

    The radial electric fields is controlled by changing the direction of neutral beam from co to counter to plasma current in tokamak, while it is controlled by the 2nd harmonic ECH and NBI and pellet injection in heliotron/torsatron. (author)

  18. Suppression and control of leakage field in electromagnetic helical microwiggler

    Energy Technology Data Exchange (ETDEWEB)

    Ohigashi, N. [Kansai Univ., Osaka (Japan); Tsunawaki, Y. [Osaka Sangyo Univ. (Japan); Imasaki, K. [Institute for Laser Technology, Osaka (Japan)] [and others

    1995-12-31

    Shortening the period of electromagnetic wiggler introduces both the radical increase of the leakage field and the decrease of the field in the gap region. The leakage field is severer problem in planar electromagnetic wiggler than in helical wiggler. Hence, in order to develop a short period electromagnetic wiggler, we have adopted {open_quotes}three poles per period{close_quotes} type electromagnetic helical microwiggler. In this work, we inserted the permanent magnet (PM) blocks with specific magnetized directions in the space between magnetic poles, for suppressing the leakage field flowing out from a pole face to the neighboring pole face. These PM-blocks must have higher intrinsic coersive force than saturation field of pole material. The gap field due to each pole is adjustable by controlling the leakage fields, that is, controlling the position of each iron screw set in each retainer fixing the PM-blocks. At present time, a test wiggler with period 7.8mm, periodical number 10 and gap length 4.6mm has been manufactured. Because the ratio of PM-block aperture to gap length is important parameter to suppress the leakage field, the parameter has been surveyed experimentally for PM-blocks with several dimensions of aperture. The field strength of 3-5kG (K=0.2-0.4) would be expected in the wiggler.

  19. Chernobyl Experience in the Field of Retrospective Dosimetry

    International Nuclear Information System (INIS)

    Chumak, V.; Bakhanova, E.

    2011-01-01

    Chernobyl accident, which occurred on April 26, 1986 at NPP located less than 150 km north of Kiev, is the largest nuclear accident ever. Unprecedented scale of the accident was determined not only by the amount of released activity, but also by a number of population and workers involved and, therefore, exposed to enhanced doses of ionizing radiation. Population of the 30-km exclusion zone numbering about 116,000 persons of all ages and both genders was evacuated within days and weeks after the accident, emergency workers called ''liquidators of the accident'' (males age 20-50) were involved into clean-up and recovery for 5 years and their number is estimated as 600,000, about 300,000 are Ukrainian citizens. Due to unexpected and excessively large scale accident, none of residents had personal dosimeters, personal dosimetry of liquidators was not total, dosimetry techniques and practices were far from the optimum. As a result, an acute need for retrospective dose assessment was dictated by radiation protection and research considerations. This need was responded by implementation of wide scale dose reconstruction efforts, which covered main exposed cohorts and encompassed broad variety of newly developed methods: analytical (time-and-motion), modeling, biological and physical (EPR spectroscopy of teeth, TL of quartz). The presentation summarizes vast experience accumulated by RCRM in the field of retrospective dosimetry of large cohorts of exposed population and professionals. These dose reconstruction projects were implemented, in particular, in the framework of epidemiological studies, designed to follow-up medical consequences of Chernobyl accident and study health effects of ionizing radiation, in particular, Ukrainian-American studies of cataracts and leukemia among liquidators. Over 25 years passed after Chernobyl accident a broad variety of retrospective dosimetry problems was addressed by the team of Research Center for Radiation Medicine AMS Ukraine. In

  20. Operational experience with the CEBAF control system

    International Nuclear Information System (INIS)

    Hovater, C.; Chowdhary, M.; Karn, J.; Tiefenback, M.; Zeijts, J. van; Watson, W.

    1996-01-01

    The CEBAF accelerator at Thomas Jefferson National Accelerator Facility (Jefferson Lab) successfully began its experimental nuclear physics program in November of 1995 and has since surpassed predicted machine availability. Part of this success can be attributed to using the EPICS (Experimental Physics and Industrial Control System) control system toolkit. The CEBAF control system is one of the largest accelerator control system now operating. It controls approximately 338 SRF cavities, 2,300 magnets, 500 beam position monitors and other accelerator devices, such as gun hardware and other beam monitoring devices. All told, the system must be able to access over 125,000 database records. The system has been well received by both operators and the hardware designers. The EPICS utilities have made the task of troubleshooting systems easier. The graphical and test-based creation tools have allowed operators to custom build control screens. In addition, the ability to integrate EPICS with other software packages, such as Tcl/Tk, has allowed physicists to quickly prototype high-level application programs, and to provide GUI front ends for command line driven tools. Specific examples of the control system applications are presented in the areas of energy and orbit control, cavity tuning and accelerator tune up diagnostics

  1. Controllability of linear vector fields on Lie groups

    International Nuclear Information System (INIS)

    Ayala, V.; Tirao, J.

    1994-11-01

    In this paper, we shall deal with a linear control system Σ defined on a Lie group G with Lie algebra g. The dynamic of Σ is determined by the drift vector field which is an element in the normalizer of g in the Lie algebra of all smooth vector field on G and by the control vectors which are elements in g considered as left-invariant vector fields. We characterize the normalizer of g identifying vector fields on G with C ∞ -functions defined on G into g. For this class of control systems we study algebraic conditions for the controllability problem. Indeed, we prove that if the drift vector field has a singularity then the Lie algebra rank condition is necessary for the controllability property, but in general this condition does not determine this property. On the other hand, we show that the rank (ad-rank) condition is sufficient for the controllability of Σ. In particular, we extend the fundamental Kalman's theorem when G is an Abelian connected Lie group. Our work is related with a paper of L. Markus and we also improve his results. (author). 7 refs

  2. Experience with the control system for the SPS

    International Nuclear Information System (INIS)

    Crowley-Milling, M.C.

    1978-01-01

    The design of the multicomputer control system for the 400 GeV Super Proton Synchrotron (SPS) at CERN was described in the report CERN 75-20, issued in 1975, before the commissioning of the accelerator. The present report, which should be read in conjunction with the earlier one, describes the modification made to the system in the light of experience, and how it has adapted to changing requirements. Reliability of the system and how it has adapted to changing requirements. Reliability of the system and of its components is discussed. Taking into account modern developments of microprocessors, etc., the changes that might be made if the system were to be redesigned are examined. Finally, the application of the design philosophy to other fields is discussed briefly. (Auth.)

  3. Plasma performance and scaling laws in the RFX-mod reversed-field pinch experiment

    International Nuclear Information System (INIS)

    Innocente, P.; Alfier, A.; Canton, A.; Pasqualotto, R.

    2009-01-01

    The large range of plasma currents (I p = 0.2-1.6 MA) and feedback-controlled magnetic boundary conditions of the RFX-mod experiment make it well suited to performing scaling studies. The assessment of such scaling, in particular those on temperature and energy confinement, is crucial both for improving the operating reversed-field pinch (RFP) devices and for validating the RFP configuration as a candidate for the future fusion reactors. For such a purpose scaling laws for magnetic fluctuations, temperature and energy confinement have been evaluated in stationary operation. RFX-mod scaling laws have been compared with those obtained from other RFP devices and numerical simulations. The role of the magnetic boundary has been analysed, comparing discharges performed with different active control schemes of the edge radial magnetic field.

  4. Controlling turbulent drag across electrolytes using electric fields.

    Science.gov (United States)

    Ostilla-Mónico, Rodolfo; Lee, Alpha A

    2017-07-01

    Reversible in operando control of friction is an unsolved challenge that is crucial to industrial tribology. Recent studies show that at low sliding velocities, this control can be achieved by applying an electric field across electrolyte lubricants. However, the phenomenology at high sliding velocities is yet unknown. In this paper, we investigate the hydrodynamic friction across electrolytes under shear beyond the transition to turbulence. We develop a novel, highly parallelised numerical method for solving the coupled Navier-Stokes Poisson-Nernst-Planck equation. Our results show that turbulent drag cannot be controlled across dilute electrolytes using static electric fields alone. The limitations of the Poisson-Nernst-Planck formalism hint at ways in which turbulent drag could be controlled using electric fields.

  5. Theorizing Surveillance in the UK Crime Control Field

    Directory of Open Access Journals (Sweden)

    Michael McCahill

    2015-09-01

    Full Text Available Drawing upon the work of Pierre Bourdieu and Loic Wacquant, this paper argues that the demise of the Keynesian Welfare State (KWS and the rise of neo-liberal economic policies in the UK has placed new surveillance technologies at the centre of a reconfigured “crime control field” (Garland, 2001 designed to control the problem populations created by neo-liberal economic policies (Wacquant, 2009a. The paper also suggests that field theory could be usefully deployed in future research to explore how wider global trends or social forces, such as neo-liberalism or bio-power, are refracted through the crime control field in different national jurisdictions. We conclude by showing how this approach provides a bridge between society-wide analysis and micro-sociology by exploring how the operation of new surveillance technologies is mediated by the “habitus” of surveillance agents working in the crime control field and contested by surveillance subjects.

  6. Complex envelope control of pulsed accelerating fields in superconducting cavities

    CERN Document Server

    Czarski, T

    2010-01-01

    A digital control system for superconducting cavities of a linear accelerator is presented in this work. FPGA (Field Programmable Gate Arrays) based controller, managed by MATLAB, was developed to investigate a novel firmware implementation. The LLRF - Low Level Radio Frequency system for FLASH project in DESY is introduced. Essential modeling of a cavity resonator with signal and power analysis is considered as a key approach to the control methods. An electrical model is represented by the non-stationary state space equation for the complex envelope of the cavity voltage driven by the current generator and the beam loading. The electromechanical model of the superconducting cavity resonator including the Lorentz force detuning has been developed for a simulation purpose. The digital signal processing is proposed for the field vector detection. The field vector sum control is considered for multiple cavities driven by one klystron. An algebraic, complex domain model is proposed for the system analysis. The c...

  7. Evaluation of completeness of selected poison control center data fields.

    Science.gov (United States)

    Jaramillo, Jeanie E; Marchbanks, Brenda; Willis, Branch; Forrester, Mathias B

    2010-08-01

    Poison control center data are used in research and surveillance. Due to the large volume of information, these efforts are dependent on data being recorded in machine readable format. However, poison center records include non-machine readable text fields and machine readable coded fields, some of which are duplicative. Duplicating this data increases the chance of inaccurate/incomplete coding. For surveillance efforts to be effective, coding should be complete and accurate. Investigators identified a convenience sample of 964 records and reviewed the substance code determining if it matched its text field. They also reviewed the coded clinical effects and treatments determining if they matched the notes text field. The substance code matched its text field for 91.4% of the substances. The clinical effects and treatments codes matched their text field for 72.6% and 82.4% of occurrences respectively. This under-reporting of clinical effects and treatments has surveillance and public health implications.

  8. Controlling radiation fields in siemans designed light water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Riess, R.; Marchl, T. [Siemens Power Generation Group, Erlangen (Germany)

    1995-03-01

    An essential item for the control of radiation fields is the minimization of the use of satellites in the reactor systems of Light Water Reactors (LWRs). A short description of the qualification of Co-replacement materials will be followed by an illustration of the locations where these materials were implemented in Siemens designed LWRs. Especially experiences in PWRs show the immense influence of reduction of cobalt sources on dose rate buildup. The corrosion and the fatique and wear behavior of the replacement materials has not created concern up to now. A second tool to keep occupational radiation doses at a low level in PWRs is the use of the modified B/Li-chemistry. This is practized in Siemens designed plants by keeping the Li level at a max. value of 2 ppm until it reaches a pH (at 300{degrees}C) of {approximately}7.4. This pH is kept constant until the end of the cycle. The substitution of cobalt base alloys and thus the removal of the Co-59 sources from the system had the largest impact on the radiation levels. Nonetheless, the effectiveness of the coolant chemistry should not be neglected either. Several years of successful operation of PWRs with the replacement materials resulted in an occupational radiation exposure which is below 0.5 man-Sievert/plant and year.

  9. Cooperative adaptive cruise control, design and experiments

    NARCIS (Netherlands)

    Naus, G.J.L.; Vugts, R.P.A.; Ploeg, J.; Molengraft, van de M.J.G.; Steinbuch, M.

    2010-01-01

    The design of a CACC system and corresponding experiments are presented. The design targets string stable system behavior, which is assessed using a frequency-domain-based approach. Following this approach, it is shown that the available wireless information enables small inter-vehicle distances,

  10. Trapped magnetic field measurements on HTS bulk by peak controlled pulsed field magnetization

    International Nuclear Information System (INIS)

    Ida, Tetsuya; Watasaki, Masahiro; Kimura, Yosuke; Miki, Motohiro; Izumi, Mitsuru

    2010-01-01

    For the past several years, we have studied the high-temperature superconducting (HTS) synchronous motor assembled with melt-textured Gd-Ba-Cu-O bulk magnets. If the single pulse field magnetizes a bulk effectively, size of electrical motor will become small for the strong magnetic field of the HTS magnets without reducing output power of motor. In the previous study, we showed that the HTS bulk was magnetized to excellent cone-shape magnetic field distribution by using the waveform control pulse magnetization (WCPM) method. The WCPM technique made possible the active control of the waveform on which magnetic flux motion depended. We generated the pulse waveform with controlled risetime for HTS bulk magnetization to suppress the magnetic flux motion which decreases magnetization efficiency. The pulsed maximum magnetic flux density with slow risetime is not beyond the maximum magnetic flux density which is trapped by the static field magnetization. But, as for applying the pulse which has fast risetime, the magnetic flux which exceed greatly the threshold penetrates the bulk and causes the disorder of the trapped magnetic distribution. This fact suggests the possibility that the threshold at pulsed magnetization influences the dynamic magnetic flux motion. In this study, Gd-Ba-Cu-O bulk is magnetized by the controlled arbitrary trapezoidal shape pulse, of which the maximum magnetic flux density is controlled not to exceed the threshold. We will present the trapped magnetic characteristics and the technique to generate the controlled pulsed field.

  11. Controlled Nucleosynthesis Breakthroughs in Experiment and Theory

    CERN Document Server

    Adamenko, Stanislav; Merwe, Alwyn

    2007-01-01

    This book ushers in a new era of experimental and theoretical investigations into collective processes, structure formation, and self-organization of nuclear matter. It reports the results of experiments wherein for the first time the nuclei constituting our world (those displayed in Mendeleev's table as well as the super-heavy ones) have been artificially created. Pioneering breakthroughs are described, achieved at the "Proton-21" Laboratory, Kiev, Ukraine, in a variety of new physical and technological directions. A detailed description of the main experiments, their analyses, and the interpretation of copious experimental data are given, along with the methodology governing key measurements and the processing algorithms of the data that empirically confirm the occurrence of macroscopic self-organizing processes leading to the nuclear transformations of various materials. The basic concepts underlying the initiation of self-sustaining collective processes that result in the formation of nuclear structures a...

  12. Temperature Field-Wind Velocity Field Optimum Control of Greenhouse Environment Based on CFD Model

    Directory of Open Access Journals (Sweden)

    Yongbo Li

    2014-01-01

    Full Text Available The computational fluid dynamics technology is applied as the environmental control model, which can include the greenhouse space. Basic environmental factors are set to be the control objects, the field information is achieved via the division of layers by height, and numerical characteristics of each layer are used to describe the field information. Under the natural ventilation condition, real-time requirements, energy consumption, and distribution difference are selected as index functions. The optimization algorithm of adaptive simulated annealing is used to obtain optimal control outputs. A comparison with full-open ventilation shows that the whole index can be reduced at 44.21% and found that a certain mutual exclusiveness exists between the temperature and velocity field in the optimal course. All the results indicate that the application of CFD model has great advantages to improve the control accuracy of greenhouse.

  13. Using a Control System Ethernet Network as a Field Bus

    CERN Document Server

    De Van, William R; Lawson, Gregory S; Wagner, William H; Wantland, David M; Williams, Ernest

    2005-01-01

    A major component of a typical accelerator distributed control system (DCS) is a dedicated, large-scale local area communications network (LAN). The SNS EPICS-based control system uses a LAN based on the popular IEEE-802.3 set of standards (Ethernet). Since the control system network infrastructure is available throughout the facility, and since Ethernet-based controllers are readily available, it is tempting to use the control system LAN for "fieldbus" communications to low-level control devices (e.g. vacuum controllers; remote I/O). These devices may or may not be compatible with the high-level DCS protocols. This paper presents some of the benefits and risks of combining high-level DCS communications with low-level "field bus" communications on the same network, and describes measures taken at SNS to promote compatibility between devices connected to the control system network.

  14. Communication: Control of chemical reactions using electric field gradients

    Energy Technology Data Exchange (ETDEWEB)

    Deshmukh, Shivaraj D.; Tsori, Yoav, E-mail: tsori@bgu.ac.il [Department of Chemical Engineering, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel)

    2016-05-21

    We examine theoretically a new idea for spatial and temporal control of chemical reactions. When chemical reactions take place in a mixture of solvents, an external electric field can alter the local mixture composition, thereby accelerating or decelerating the rate of reaction. The spatial distribution of electric field strength can be non-trivial and depends on the arrangement of the electrodes producing it. In the absence of electric field, the mixture is homogeneous and the reaction takes place uniformly in the reactor volume. When an electric field is applied, the solvents separate and the reactants are concentrated in the same phase or separate to different phases, depending on their relative miscibility in the solvents, and this can have a large effect on the kinetics of the reaction. This method could provide an alternative way to control runaway reactions and to increase the reaction rate without using catalysts.

  15. Communication: Control of chemical reactions using electric field gradients.

    Science.gov (United States)

    Deshmukh, Shivaraj D; Tsori, Yoav

    2016-05-21

    We examine theoretically a new idea for spatial and temporal control of chemical reactions. When chemical reactions take place in a mixture of solvents, an external electric field can alter the local mixture composition, thereby accelerating or decelerating the rate of reaction. The spatial distribution of electric field strength can be non-trivial and depends on the arrangement of the electrodes producing it. In the absence of electric field, the mixture is homogeneous and the reaction takes place uniformly in the reactor volume. When an electric field is applied, the solvents separate and the reactants are concentrated in the same phase or separate to different phases, depending on their relative miscibility in the solvents, and this can have a large effect on the kinetics of the reaction. This method could provide an alternative way to control runaway reactions and to increase the reaction rate without using catalysts.

  16. Using Field Experiments to Evaluate the Impact of Financial Planning and Counseling Interventions

    Science.gov (United States)

    Collins, J. Michael

    2017-01-01

    Field experiments, which are a powerful research technique, are common in some fields, but they have not been widely used in studying the effect of financial and counseling planning interventions. Financial services can benefit from the expanded use of field experiments to explore potential causal mechanisms for the effects of financial planning…

  17. Efficacy of Maister OD (Foramsulfuron + Idosulfuron a New Herbicide in Controlling Weeds of Corn Fields

    Directory of Open Access Journals (Sweden)

    J. Abdi

    2012-07-01

    Full Text Available To evaluate the efficacy of a new herbicide Foramsulfuron +Idosulfuron (Maister OD against other herbicides in corn fields, this experiment was fulfielld in 2010 at Mahidasht, Research Center of Agriculture and Natural Resources of Kermanshah, Iran. It was concucted in randomized complete block design with four replications and 11 treatments. In this experiment, three doses of herbicides (38.75, 46.5 and 54.25 g/ha including foramsulfuron + idosulfuron along with Nicusulfuron, ForamSulfuron, Rimsulfuron, Foramsulfuron + Rimsulfuron , Bromicid + hand weeding narrow leaf weeds, Bromicid + Nicusulfuron and U46 + hand weeding of narrow leaf weeds and a complete weeding as the control treatments were investigated. Weeds present in the field were Xanthium stromarium,Chenopedium album, Portulaca oleracea, Sorgum halepense and Setaria virdis. The results of this study showed that doses 38.75 and 46.5 g/ha of herbicide foramsulfuron + idosulfuron after treatments of Bromicid + Nicusulfuron and, Bromicid + narrow leaf weed, hand weeding respectively could control 90 and 86 % of weeds in corn field and increase its yields significantly. Because there are presently few registered herbicide available in Iran, necessity of finding proper herbicides to control weeds in corn field and based on the results oblained from this experiment it seems using 46.5 and 38-75 grams per hectare respectively of foramsulfuron + idosulfuron could be a better option than other herbicides to control weeds in corn fields and increase its seed yield.

  18. Rotating magnetic field current drive-theory and experiment

    International Nuclear Information System (INIS)

    Donnelly, I.J.

    1989-01-01

    Rotating magnetic fields have been used to drive plasma current and establish a range of compact torus configurations, named rotamaks. The current drive mechanism involves a ponderomotive force acting on the electron fluid. Recent extensions of the theory indicate that this method is most suitable for driving currents in directions perpendicular to the steady magnetic fields

  19. Computer controls for the WITCH experiment

    Czech Academy of Sciences Publication Activity Database

    Tandecki, M.; Beck, M.; Beck, D.; Brand, H.; Breitenfeldt, M.; De Leebeeck, V.; Friedag, P.; Herlert, A.; Kozlov, V.; Mader, J.; Roccia, S.; Soti, G.; Traykov, E.; Van Gorp, S.; Wauters, F.; Weinheimer, C.; Zákoucký, Dalibor; Severijns, N.

    2011-01-01

    Roč. 629, č. 1 (2011), s. 369-405 ISSN 0168-9002 R&D Projects: GA MŠk LA08015 Institutional research plan: CEZ:AV0Z10480505; CEZ:AV0Z10100523 Keywords : LabVIEW * Control system * Distributed programming Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.207, year: 2011

  20. Reproducibility, Controllability, and Optimization of Lenr Experiments

    Science.gov (United States)

    Nagel, David J.

    2006-02-01

    Low-energy nuclear reaction (LENR) measurements are significantly and increasingly reproducible. Practical control of the production of energy or materials by LENR has yet to be demonstrated. Minimization of costly inputs and maximization of desired outputs of LENR remain for future developments.

  1. ADX: a high field, high power density, Advanced Divertor test eXperiment

    Science.gov (United States)

    Vieira, R.; Labombard, B.; Marmar, E.; Irby, J.; Shiraiwa, S.; Terry, J.; Wallace, G.; Whyte, D. G.; Wolfe, S.; Wukitch, S.; ADX Team

    2014-10-01

    The MIT PSFC and collaborators are proposing an advanced divertor experiment (ADX) - a tokamak specifically designed to address critical gaps in the world fusion research program on the pathway to FNSF/DEMO. This high field (6.5 tesla, 1.5 MA), high power density (P/S ~ 1.5 MW/m2) facility would utilize Alcator magnet technology to test innovative divertor concepts for next-step DT fusion devices (FNSF, DEMO) at reactor-level boundary plasma pressures and parallel heat flux densities while producing high performance core plasma conditions. The experimental platform would also test advanced lower hybrid current drive (LHCD) and ion-cyclotron range of frequency (ICRF) actuators and wave physics at the plasma densities and magnetic field strengths of a DEMO, with the unique ability to deploy launcher structures both on the low-magnetic-field side and the high-field side - a location where energetic plasma-material interactions can be controlled and wave physics is most favorable for efficient current drive, heating and flow drive. This innovative experiment would perform plasma science and technology R&D necessary to inform the conceptual development and accelerate the readiness-for-deployment of FNSF/DEMO - in a timely manner, on a cost-effective research platform. Supported by DE-FC02-99ER54512.

  2. Communication, Community, and Disconnection: Pre-Service Teachers in Virtual School Field Experiences

    Science.gov (United States)

    Wilkens, Christian; Eckdahl, Kelli; Morone, Mike; Cook, Vicki; Giblin, Thomas; Coon, Joshua

    2014-01-01

    This study examined the experiences of 11 graduate-level pre-service teachers completing Virtual School Field Experiences (VSFEs) with cooperating teachers in fully online, asynchronous high school courses in New York State. The VSFEs included a 7-week online teacher training course, and a 7-week online field experience. Pre-service teachers…

  3. Generation Of Unipolar Field For The Control Of Charges

    Directory of Open Access Journals (Sweden)

    Barnabas Oluwaseyi Alabi

    2017-10-01

    Full Text Available Electric charge is the property of a matter that allow for electric and magnetic forces interaction. These charges can be controlled by unipolar electromagnetic field. In this study such unipolar field that can propagate was generated. This unipolar electromagnetic field was simulated and tested for propagation. To produce a propagating unipolar magnetic field a time-varying unipolar electric current generator was considered. The model considered was simulated in the National Instruments Multisim windows application environment. The generated electric voltage waveform was viewed via the output grapher of the application. Various loads were connected to ensure consistency in the unipolar waveform for different load value on the generator. The result obtained showed that a unipolar field which could propagate can be achievable only when the signal involved was properly rectified. After rectification however the desired waveform and signal was produced. The test for propagation was done using a core of iron and a small solenoid connected to the rectified output and the field produced was magnetic this attracted a metal clip 1.0 cm away and a larger core attracted a hammer from around 10.0 cm away. The study concluded that a propagating magnetic field useful for the control of charges can be generated if the signal involved is made to be unipolar in nature.

  4. Pyranometer offsets triggered by ambient meteorology: insights from laboratory and field experiments

    Science.gov (United States)

    Oswald, Sandro M.; Pietsch, Helga; Baumgartner, Dietmar J.; Weihs, Philipp; Rieder, Harald E.

    2017-03-01

    This study investigates the effects of ambient meteorology on the accuracy of radiation (R) measurements performed with pyranometers contained in various heating and ventilation systems (HV-systems). It focuses particularly on instrument offsets observed following precipitation events. To quantify pyranometer responses to precipitation, a series of controlled laboratory experiments as well as two targeted field campaigns were performed in 2016. The results indicate that precipitation (as simulated by spray tests or observed under ambient conditions) significantly affects the thermal environment of the instruments and thus their stability. Statistical analyses of laboratory experiments showed that precipitation triggers zero offsets of -4 W m-2 or more, independent of the HV-system. Similar offsets were observed in field experiments under ambient environmental conditions, indicating a clear exceedance of BSRN (Baseline Surface Radiation Network) targets following precipitation events. All pyranometers required substantial time to return to their initial signal states after the simulated precipitation events. Therefore, for BSRN-class measurements, the recommendation would be to flag the radiation measurements during a natural precipitation event and 90 min after it in nighttime conditions. Further daytime experiments show pyranometer offsets of 50 W m-2 or more in comparison to the reference system. As they show a substantially faster recovery, the recommendation would be to flag the radiation measurements within a natural precipitation event and 10 min after it in daytime conditions.

  5. Experience with dynamic material control subsystems

    International Nuclear Information System (INIS)

    Severe, W.R.; Hagen, J.; Siebelist, R.; Wagner, R.P.; Olson, W.M.

    1977-01-01

    Operation of a Dynamic Material Control (DYMAC) prototype system has yielded some useful information for installing the final system. We discovered a bias between two methods for measuring filtrates. Evaluation of a unit process dynamic balance brought to light an operating procedure that weakens the accountability goals of the DYMAC system. We were able to correct both situations for the final system and learned that we must regularly monitor the system once it is operational for similar discrepancies

  6. Brookhaven Reactor Experiment Control Facility, a distributed function computer network

    International Nuclear Information System (INIS)

    Dimmler, D.G.; Greenlaw, N.; Kelley, M.A.; Potter, D.W.; Rankowitz, S.; Stubblefield, F.W.

    1975-11-01

    A computer network for real-time data acquisition, monitoring and control of a series of experiments at the Brookhaven High Flux Beam Reactor has been developed and has been set into routine operation. This reactor experiment control facility presently services nine neutron spectrometers and one x-ray diffractometer. Several additional experiment connections are in progress. The architecture of the facility is based on a distributed function network concept. A statement of implementation and results is presented

  7. Adaptive Augmenting Control and Launch Vehicle Adaptive Control Flight Experiments

    Data.gov (United States)

    National Aeronautics and Space Administration — Researchers at NASA Armstrong are working to further the development of an adaptive augmenting control algorithm (AAC). The AAC was developed to improve the...

  8. Field reversal experiments (FRX). [Equilibrium, confinement, and stability

    Energy Technology Data Exchange (ETDEWEB)

    Linford, R.K.; Armstrong, W.T.; Platts, D.A.; Sherwood, E.G.

    1978-01-01

    The equilibrium, confinement, and stability properties of the reversed-field configuration (RFC) are being studied in two theta-pinch facilities. The RFC is an elongated toroidal plasma confined in a purely poloidal field geometry. The open field lines of the linear theta pinch support the closed-field RFC much like the vertical field centers the toroidal plasma in a tokamak. Depending on stability and confinement properties, the RFC might be used to greatly reduce the axial losses in linear fusion devices such as mirrors, theta pinches, and liners. The FRX systems produce RFC's with a major radius R = 2-6 cm, minor radius a approximately 2 cm, and a total length l approximately 35 cm. The observed temperatures are T/sub e/ approximately 100 eV and T/sub i/ = 150-350 eV with a peak density n approximately 2 x 10/sup 15/ cm/sup -3/. After the plasma reaches equilibrium, the RFC remains stable for up to 30 ..mu..s followed by the rapid growth of the rotational m = 2 instability, which terminates the confinement. During the stable equilibrium, the particle and energy confinement times are more than 10 times longer than in an open-field system. The behavior of the m = 2 mode qualitatively agrees with the theoretically predicted instability for rotational velocities exceeding some critical value.

  9. Catheter visualisation in MR tomography: first animal experimental experiences with field inhomogeneity catheters

    International Nuclear Information System (INIS)

    Adam, G.; Glowinski, A.; Neuerburg, J.; Buecker, A.; Vaals, J.J. van; Hurtak, W.; Guenther, R.W.

    1997-01-01

    Purpose: To assess the feasibility of a new developed field inhomogeneity catheter for interventional MR imaging in vivo. Materials and methods: Three different prototypes of a field inhomogeneity catheter were investigated in 6 pigs. The catheters were introduced in Seldinger technique via the femoral vessels over a guide wire on an interventional MR system (Philips Gyroscan NT combined with a C-arm fluoroscopy unit [Philips BV 212[). Catheters were placed in veins and arteries. The catheter position was controlled by a fast gradient echo sequence (Turbo Field Echo [TEF[). Results: Catheters were introduced over a guide wire without complications in all cases. Using the field inhomogeneity concept, catheters were easily visualised in the inferior vena cava and the aorta by the fast gradient echo technique on MR in all cases. Although aortic branches were successfully cannulated, the catheters were not displayed by the TFE technique due to the complex and tortuous anatomy. All animals survived the experiments without complications. Conclusion: MR guided visualisation of a field inhomogeneity catheter is a simple concept which can be realised on each MR scanner and may allow intravascular MR guided interventions in future. (orig.) [de

  10. [Our experience with outside laboratory quality control].

    Science.gov (United States)

    Dochev, D; Arakasheva, V; Nashkov, A; Tsachev, K

    1979-01-01

    The results from the national outside laboratory qualitative control of the clinical diagnostic laboratory investigations for the period September 1975 -- May 1977 were described. The following interlaboratory discrepancy was found on base of a systematic analysis of the data from the last two ring-like check-ups, November 1976 and May 1977, exressed by the variation coefficient (V.C. %); total protein, sodium, potassium and chlorides -- under 10%; cholesterol, urea and total fats -- between 10 and 20%; calcium, phosphorus, iron and creatinine -- over 20%. The highest per cent of admissible results are found with total protein -- to 85%; cholesterol -- to 70.38%; glucosa -- to 73.17%, urea -- to 69.23%, potassium -- to 59.46%, chlorides -- to 57.9%. With sodium, phosphorus, calcium, iron creatinine and uric acid the "admissibility" fluctuates about or under 50 per cent. The values of the qualitative-control indices discussed are comparable with the values obtained from them in the interlaboratory comparisons of other countries.

  11. Calculations of self-generated magnetic fields in parylene disc experiments

    International Nuclear Information System (INIS)

    Dahlbacka, G.H.; Mead, W.C.; Max, C.E.; Thomson, J.J.

    1975-01-01

    Experiments have been planned at Livermore to measure self-generated magnetic fields using the Faraday Rotation of frequency quadrupled 1.1 μm laser light. The LASNEX code was used during the planning of these experiments and has provided valuable information in establishing the conditions under which the thermoelectric fields expected can be measured. Suspected thermoelectric fields have been inferred from experiments that have been carried out at NRL

  12. Application of programmable logic controller in nuclear experiments

    International Nuclear Information System (INIS)

    Ponikvar, D.

    1991-09-01

    The applicability of programmable logic controller (PLC) in nuclear experiments was studied on an example that simulated the monitoring and control of an ion beam in an accelerator. Using infrared and laser light, a comparison was made between the complexity and suitability of PLC compared to a setup using a personal computer. The experiments are described in detail. The routines for registration of signals from appropriate sensors and for control of the stepper monitor were written in quick BASIC. (author). 5 figs

  13. A ferrofluid based artificial tactile sensor with magnetic field control

    Energy Technology Data Exchange (ETDEWEB)

    Volkova, T.I., E-mail: tatiana.volkova@tu-ilmenau.de [Technical Mechanics Group, Faculty of Mechanical Engineering, Technische Universität Ilmenau, Ilmenau D-98684 (Germany); Böhm, V., E-mail: valter.boehm@tu-ilmenau.de [Technical Mechanics Group, Faculty of Mechanical Engineering, Technische Universität Ilmenau, Ilmenau D-98684 (Germany); Naletova, V.A., E-mail: naletova@imec.msu.ru [Faculty of Mechanics and Mathematics, Lomonosov Moscow State University, 119991 Moscow (Russian Federation); Kaufhold, T., E-mail: tobias.kaufhold@tu-ilmenau.de [Technical Mechanics Group, Faculty of Mechanical Engineering, Technische Universität Ilmenau, Ilmenau D-98684 (Germany); Becker, F., E-mail: felix.becker@tu-ilmenau.de [Technical Mechanics Group, Faculty of Mechanical Engineering, Technische Universität Ilmenau, Ilmenau D-98684 (Germany); Zeidis, I., E-mail: igor.zeidis@tu-ilmenau.de [Technical Mechanics Group, Faculty of Mechanical Engineering, Technische Universität Ilmenau, Ilmenau D-98684 (Germany); Zimmermann, K., E-mail: klaus.zimmermann@tu-ilmenau.de [Technical Mechanics Group, Faculty of Mechanical Engineering, Technische Universität Ilmenau, Ilmenau D-98684 (Germany)

    2017-06-01

    The paper deals with a tactile sensor inspired by biological hairs of mammals. The working principle is based on the effect of the magnetic force exerted on a paramagnetic body submerged into a ferrofluid volume under the influence of a nonuniform magnetic field. The deflection of the sensor's rod caused by external mechanical stimuli may be unambiguously identified by the distortion of the magnetic field, which occurs due to the motion of the attached body in the ferrofluid. The magnetic force acting on the body is evaluated experimentally and theoretically for the nonuniform magnetic field of a permanent magnet. The controlled oscillations of the rod are realised by applying a nonuniform magnetic field of periodically altering direction. - Highlights: • A design approach of a tactile sensor inspired by special mammalian hairs is presented. • The working principle is based on magnetic properties of a ferrofluid in magnetic fields. • The magnetic force acting on a body submerged into a ferrofluid volume is evaluated. • External mechanical stimuli may be identified by the distortion of the magnetic field. • The controlled whisking-like oscillations of the sensor's rod are realised experimentally.

  14. A ferrofluid based artificial tactile sensor with magnetic field control

    International Nuclear Information System (INIS)

    Volkova, T.I.; Böhm, V.; Naletova, V.A.; Kaufhold, T.; Becker, F.; Zeidis, I.; Zimmermann, K.

    2017-01-01

    The paper deals with a tactile sensor inspired by biological hairs of mammals. The working principle is based on the effect of the magnetic force exerted on a paramagnetic body submerged into a ferrofluid volume under the influence of a nonuniform magnetic field. The deflection of the sensor's rod caused by external mechanical stimuli may be unambiguously identified by the distortion of the magnetic field, which occurs due to the motion of the attached body in the ferrofluid. The magnetic force acting on the body is evaluated experimentally and theoretically for the nonuniform magnetic field of a permanent magnet. The controlled oscillations of the rod are realised by applying a nonuniform magnetic field of periodically altering direction. - Highlights: • A design approach of a tactile sensor inspired by special mammalian hairs is presented. • The working principle is based on magnetic properties of a ferrofluid in magnetic fields. • The magnetic force acting on a body submerged into a ferrofluid volume is evaluated. • External mechanical stimuli may be identified by the distortion of the magnetic field. • The controlled whisking-like oscillations of the sensor's rod are realised experimentally.

  15. Fugitive dust control experiments using soil fixatives on vehicle traffic surfaces

    International Nuclear Information System (INIS)

    Winberg, M.R.; Wixom, V.E.

    1992-08-01

    This report presents the results of engineering scale dust control experiments using soil fixative for contamination control during handling of transuranic waste. These experiments focused on controlling dust during retrieval operations of buried waste where waste and soil are intimately mixed. Sources of dust generation during retrieval operations include digging, dumping, and vehicle traffic. Because contaminants are expected to attach to soil particles and move with the generated dust, control of the dust spread may be the key to contamination control. Dust control techniques examined in these experiments include the use of soil fixatives to control generation of fugitive dusts during vehicle traffic operations. Previous experiments conducted in FY 1990 included testing of the soil fixative, ENTAC. These experiments showed that ENTAC was effective in controlling dust generation but had several undesirable properties such as slow cure times and clogged the pumps and application nozzles. Therefore, other products would have to be evaluated to find a suitable candidate. As a result, two soil fixatives were tested in these present experiments, COHEREX-PM, an asphalt emulsion product manufactured by Witco Corporation and FLAMBINDER, a calcium lignosulfonate product manufactured by Flambeau Corporation. The results of the experiments include product performance and recommended application methods for application in a field deployable contamination control unit to be built in FY 1993

  16. Controlled VLF phase reversal experiment in the magnetosphere

    International Nuclear Information System (INIS)

    Koons, H.C.; Dazey, M.H.; Dowden, R.L.; Amon, L.E.S.

    1976-01-01

    During the 1973 operations of the transportable very low frequency transmitter near Anchorage, Alaska (Lapprox.4), an experiment was performed to determine the effect of controlled phase change of the transmitted wave on the magnetospherically propagated signal received in the conjugate region. At periodic intervals the phase of the driving voltage was changed (essentially instantaneously) by 180degree. The amplitude of the 6.6-kHz signal detected in the conjugate region went to zero and recovered with a characteristic time constant of 33 ms. This is 10 times longer than the antenna current response time and is in fact comparable with characteristic electron interaction times with whistler mode waves. Between the times at which the phase reversals occurred the received signal was amplitude modulated. The period of the modulation was approx.26 ms. An upper side band was present in the spectrum while these pulsations were occurring. These characteristic times are in general agreement with theoretical predictions of bandwidths, growth rates, and particle-trapping frequencies for whistler instabilities in the magnetosphere. Data obtained from the controlled transmissions and from lightning-generated whistlers propagating in the same duct were combined to determine the plasma and wave parameters at the geomagnetic equator. Of particular interest is the level at which the magnetic field of the wave saturated. During the time period for which the data were analyzed this was found to be 3.5 pT (mγ)

  17. The Levitation Control System for the Levitated Dipole Experiment

    Science.gov (United States)

    Garnier, D. T.; Hansen, A. K.; Mauel, M. E.; Pedersen, T. Sunn; Dagen, S.; Kesner, J.; Liptac, J.

    2001-10-01

    The confining field in the Levitated Dipole Experiment (LDX) is provided by a 1/2 ton levitated superconducting dipole magnet. This floating coil is charged with 1.5 MA current and will be levitated continuously for the eight hour experimental run day. Earnshaw's theorem states that there exists no statically stable configuration for levitation of magnets. In LDX, the floating coil is levitated by a smaller dipole levitation coil 1.5 meters above. This configuration is unstable vertically, but stable in tilt or horizontal motion. The position of the coil will be monitored with a set of eight laser position detectors giving redundant measurements of the five degrees of freedom of the floating coil. The levitation will then be stabilized by feedback control of the current in the levitation coil. The feedback system is a digital system running on a real time operating system platform. This system is programmed, monitored, and controlled by a second computer using Matlab Simulink. The system is currently being tested on a small model and a larger test is planned before LDX operation. Results from these tests and optimizations will be presented.

  18. Probe-Hole Field Emission Microscope System Controlled by Computer

    Science.gov (United States)

    Gong, Yunming; Zeng, Haishan

    1991-09-01

    A probe-hole field emission microscope system, controlled by an Apple II computer, has been developed and operated successfully for measuring the work function of a single crystal plane. The work functions on the clean W(100) and W(111) planes are measured to be 4.67 eV and 4.45 eV, respectively.

  19. Environmental Control Plan for the Industrial Hygiene Field Services Facility

    International Nuclear Information System (INIS)

    Donnelly, J.W.

    2000-01-01

    This environmental control plan is for the Hanford Site's Industrial Hygiene Field Services Facility, located in the 100-N Area. This facility is used for the maintenance and storage of respirators, respiratory equipment and testing, calibration and testing of industrial hygiene equipment, and asbestos fiber counting

  20. Microelectrode for energy and current control of nanotip field electron emitters

    International Nuclear Information System (INIS)

    Lüneburg, S.; Müller, M.; Paarmann, A.; Ernstorfer, R.

    2013-01-01

    Emerging experiments and applications in electron microscopy, holography, and diffraction benefit from miniaturized electron guns for compact experimental setups. We present a highly compact microelectrode integrated field emitter that consists of a tungsten nanotip coated with a few micrometers thick polyimide film followed by a several nanometers thick gold film, both positioned behind the exposed emitter apex by approximately 10–30 μm. The control of the electric field strength at the nanometer scale tip apex allows suppression, extraction, and energy tuning of field-emitted electrons. The performance of the microelectrode is demonstrated experimentally and supported by numerical simulations

  1. On the design and implementation of environmental conservation mechanisms : Evidence from field experiments

    NARCIS (Netherlands)

    Kitesa, Rahel

    2018-01-01

    This doctoral dissertation consists of three chapters on the design and implementation of environmental conservation mechanisms using economic experiments. The first chapter examines how variations in information and context affect the outcomes of valuation using field experiment. The chapter shows

  2. Control of thermal therapies with moving power deposition field

    International Nuclear Information System (INIS)

    Arora, Dhiraj; Minor, Mark A; Skliar, Mikhail; Roemer, Robert B

    2006-01-01

    A thermal therapy feedback control approach to control thermal dose using a moving power deposition field is developed and evaluated using simulations. A normal tissue safety objective is incorporated in the controller design by imposing constraints on temperature elevations at selected normal tissue locations. The proposed control technique consists of two stages. The first stage uses a model-based sliding mode controller that dynamically generates an 'ideal' power deposition profile which is generally unrealizable with available heating modalities. Subsequently, in order to approximately realize this spatially distributed idealized power deposition, a constrained quadratic optimizer is implemented to compute intensities and dwell times for a set of pre-selected power deposition fields created by a scanned focused transducer. The dwell times for various power deposition profiles are dynamically generated online as opposed to the commonly employed a priori-decided heating strategies. Dynamic intensity and trajectory generation safeguards the treatment outcome against modelling uncertainties and unknown disturbances. The controller is designed to enforce simultaneous activation of multiple normal tissue temperature constraints by rapidly switching between various power deposition profiles. The hypothesis behind the controller design is that the simultaneous activation of multiple constraints substantially reduces treatment time without compromising normal tissue safety. The controller performance and robustness with respect to parameter uncertainties is evaluated using simulations. The results demonstrate that the proposed controller can successfully deliver the desired thermal dose to the target while maintaining the temperatures at the user-specified normal tissue locations at or below the maximum allowable values. Although demonstrated for the case of a scanned focused ultrasound transducer, the developed approach can be extended to other heating modalities with

  3. Experience with ActiveX control for simple channel access

    International Nuclear Information System (INIS)

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

    2003-01-01

    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

  4. Numerical studies of active current profile control in the reversed-field pinch

    International Nuclear Information System (INIS)

    Dahlin, J-E; Scheffel, J; Anderson, J K

    2007-01-01

    Quenching of the reversed-field pinch (RFP) dynamo is observed in numerical simulations using current profile control. A novel algorithm employing active feedback of the dynamo field has been utilized. The quasi-steady state achieved represents an important improvement as compared with earlier numerical work and may indicate a direction for the design of future experiments. Both earlier and the novel schemes of feedback control result in quasi-single helicity states. The energy confinement time and poloidal beta are observed to be substantially increased, as compared with the conventional RFP, in both the cases. Different techniques for experimental implementation are discussed

  5. Ensemble control of the Hardhof well field under constraints

    Science.gov (United States)

    Marti, Beatrice; McLaughlin, Dennis; Kinzelbach, Wolfgang; Kaiser, Hans-Peter

    2013-04-01

    Practical control of flow in aquifers has been based on deterministic models, not including stochastic information in the optimization (Bauser et al., 2010 or Marti et al., 2012). Only recently robust ensemble control of aquatic systems has been analyzed in linear and synthetic problems (Lin, B., 2012). We propose a control under constraints, which takes into account the stochastic information contained in an ensemble of realizations of a groundwater flow model with uncertain parameters, boundary and initial conditions. This control is applied to a real life problem setting (the Hardhof well field in Zurich) and analyzed with regard to efficiency of the control compared to a similar control based on a deterministic model. The Hardhof well field, which lies in the city of Zurich, Switzerland, provides roughly 15% of the town's drinking water demand from the Limmat valley aquifer. Groundwater and river filtrate are withdrawn in four large horizontal wells, each with a capacity of up to 48'000 m3 per day. The well field is threatened by potential pollution from leachate of a nearby land fill, possible accidents on the adjacent rail and road lines, and by diffuse pollution from former industrial sites and sewers located upstream of the well field. A line of recharge wells and basins forms a hydraulic barrier against the potentially contaminated water and increases the capacity of the well field. The amount and distribution of the artificial recharge to 3 infiltration basins and 12 infiltration wells has to be controlled on a daily basis to guarantee the effectiveness of the hydraulic barrier in the highly dynamic flow field. The Hardhof well field is simulated with a 2D-real-time groundwater flow model. The model is coupled to a controller, minimizing the inflow of potentially contaminated groundwater to the drinking water wells under various constraints (i.e. keeping the groundwater level between given thresholds, guaranteeing production of the drinking water demand

  6. Simulation experiment on magnetic field reconnection processes in tokamak

    International Nuclear Information System (INIS)

    Kiwamoto, Y.

    1982-01-01

    Two experimental studies on magnetic field line reconnection processes relevant to tokamak physics are going on in Japan. In Yokohama National University, reconnection of poloidal magnetic field lines is studied by the author when reversing the toroidal current of a small toroidal plasma in a short period (typically less than 4 μsec). Interaction of two current carrying plasma (linear) columns is being studied by Kawashima and his coleagues in Institute of Space and Aeronautical Sciences. Mutual attraction and merging of the plasma columns and resulting plasma heating are reported. (author)

  7. A replicated climate change field experiment reveals rapid evolutionary response in an ecologically important soil invertebrate

    DEFF Research Database (Denmark)

    Bataillon, Thomas; Galtier, Nicolas; Bernard, Aurelien

    2016-01-01

    to climate change in a common annelid worm using a controlled replicated experiment where climatic conditions were manipulated in a natural setting. Analyzing the transcribed genome of 15 local populations, we found that about 12% of the genetic polymorphisms exhibit differences in allele frequencies......Whether species can respond evolutionarily to current climate change is crucial for the persistence of many species. Yet, very few studies have examined genetic responses to climate change in manipulated experiments carried out innatural field conditions. We examined the evolutionary response...... associated to changes in soil temperature and soil moisture. This shows an evolutionaryresponse to realistic climate change happening over short-time scale, and calls for incorporating evolution into modelspredicting future response of species to climate change. It also shows that designed climate change...

  8. Advanced Biasing Experiments on the C-2 Field-Reversed Configuration Device

    Science.gov (United States)

    Thompson, Matthew; Korepanov, Sergey; Garate, Eusebio; Yang, Xiaokang; Gota, Hiroshi; Douglass, Jon; Allfrey, Ian; Valentine, Travis; Uchizono, Nolan; TAE Team

    2014-10-01

    The C-2 experiment seeks to study the evolution, heating and sustainment effects of neutral beam injection on field-reversed configuration (FRC) plasmas. Recently, substantial improvements in plasma performance were achieved through the application of edge biasing with coaxial plasma guns located in the divertors. Edge biasing provides rotation control that reduces instabilities and E × B shear that improves confinement. Typically, the plasma gun arcs are run at ~ 10 MW for the entire shot duration (~ 5 ms), which will become unsustainable as the plasma duration increases. We have conducted several advanced biasing experiments with reduced-average-power plasma gun operating modes and alternative biasing cathodes in an effort to develop an effective biasing scenario applicable to steady state FRC plasmas. Early results show that several techniques can potentially provide effective, long-duration edge biasing.

  9. Climate chamber for environmentally controlled laboratory airflow experiments.

    Science.gov (United States)

    Even-Tzur, Nurit; Zaretsky, Uri; Grinberg, Orly; Davidovich, Tomer; Kloog, Yoel; Wolf, Michael; Elad, David

    2010-01-01

    Climate chambers have been widely used in in vitro and in vivo studies which require controlled environmental temperature and humidity conditions. This article describes a new desktop climate chamber that was developed for application of respiratory airflows on cultured nasal epithelial cells (NEC) under controlled temperature and humidity conditions. Flow experiments were performed by connecting the climate chamber to an airflow generator via a flow chamber with cultured NEC. Experiments at two controlled climate conditions, 25 degrees C and 40% relative humidity (RH) and 37 degrees C and 80%RH, were conducted to study mucin secretion from the cultures inresponse to the flow. The new climate chamber is a relatively simple and inexpensive apparatus which can easily be connected to any flow system for climate controlled flow experiments. This chamber can be easily adjusted to various in vitro experiments, as well as to clinical studies with animals or human subjects which require controlled climate conditions.

  10. Divertor experiment for impurity control in DIVA

    International Nuclear Information System (INIS)

    Nagami, Masayuki

    1979-04-01

    Divertor actions of controlling the impurities and the transport of impurity ions in the plasma have been investigated in the DIVA device. Following are the results: (1) The radial transport of impurity ions is not described only by neoclassical theory, but it is strongly influenced by anomalous process. Radial diffusion of impurity ions across the whole minor radius is well described by a neoclassical diffusion superposed by the anomalous diffusion for protons. Due to this anomalous process, which spreads the radial density profile of impurity ions, 80 to 90% of the impurity flux in the plasma outer edge is shielded even in a nondiverted discharge. (2) The divertor reduces the impurity flux entering the main plasma by a factor of 2 to 4. The impurity ions shielded by the scrape-off plasma are rapidly guided into the burial chamber with a poloidal excursion time roughly equal to that of the scrape-off plasma. (3) The divertor reduces the impurity ion flux onto the main vacuum chamber by guiding the impurity ions diffusing from the main plasma into the burial chamber, thereby reducing the plasma-wall interaction caused by diffusing impurity ions at the main vacuum chamber. The impurity ions produced in the burial chamber may flow back to the main plasma through the scrape-off layer. However, roughly only 0.3% of the impurity flux into the scrape-off plasma in the burial chamber penetrates into the main plasma due to the impurity backflow. (4) A slight cooling of the scrape-off plasma with light-impurity injection effectively reduces the metal impurity production at the first wall by reducing the potential difference between the plasma and the wall, thereby reducing the accumulation of the metal impurity in the discharge. Radiation cooling by low-Z impurities in the plasma outer edge, which may become an important feature in future large tokamaks both with and without divertor, is numerically evaluated for carbon, oxygen and neon. (author)

  11. The Field Trip Book: Study Travel Experiences in Social Studies

    Science.gov (United States)

    Morris, Ronald V.

    2010-01-01

    Looking for social studies adventures to help students find connections to democratic citizenship? Look no further! This book provides just the answer teachers need for engaging students in field trips as researching learners with emphasis on interdisciplinary social studies plus skills in collecting and reporting data gathered from field…

  12. Too poor to be green consumers? A field experiment on revealed preferences for firewood in rural Guatemala

    NARCIS (Netherlands)

    Kempen, L.A.C.M. van; Muradian Sarache, R.P.; Sandóval, C.; Castañeda, P.

    2009-01-01

    The paper reports on a field experiment that investigates whether households in Guatemala are willing to surrender a small material gain in order to buy legal rather than illegal firewood. Given the ineffectiveness of command-and-control policies to curb the problem of illegal logging in Guatemala,

  13. Tropospheric ozone lidar intercomparison experiment, TROLIX '91, field phase report

    International Nuclear Information System (INIS)

    Boesenberg, J.; Ancellet, G.; Bergwerff, H.; Cossart, G. v.; Fiedler, J.; Jonge, C. de; Mellqvist, J.; Mitev, V.; Sonnemann, G.; Swart, D.; Wallinder, E.

    1993-01-01

    The Tropospheric Ozone Lidar Intercomparison Experiment TROLIX '91 has been initiated as part of the TESLAS subproject of the cooperative programme EUROTRAC. It has been performed in June 1991 at the Rijksinstitut voor Volksgezondheid en Milieuhygiene (RIVM) in Bilthoven, The Netherlands. The experiment was based on the simultaneous operation of different types of differential absorption lidars (DIAL), a special version of a Differential Optical Absorption Spectroscopy Instrument (DOAS), helicopter borne in situ instruments, and many other supporting measurements. After a short introduction to the general methodology the instruments are described, the experimental operations are explained, and a selection of data are presented. Some examples are given for the results of the intercomparison, as far as they have been available at the present stage of evaluation. The main purpose of this report, however, is to provide an overview over the material collected during the experiment, on order to facilitate further detailed studies in cooperation between the different groups which have participated. (orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, Yasuo; Nakajima, Mitsuo; Horioka, Kazuhiko [Department of Energy Sciences, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502 (Japan)

    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.

  15. Early Pottery Making in Northern Coastal Peru. Part II: Field Firing Experiments

    Science.gov (United States)

    Shimada, I.; Goldstein, D.; Sosa, J.; Wagner, U.

    2003-09-01

    We present data from three seasons of experimental field work designed to recreate ancient Andean coastal ceramic firing techniques. Based on the recent discovery of two different archaeological ceramic production sites in the La Leche river valley of northern coastal Peru, the opportunity arose to apply Mössbauer spectroscopy and other analytical methods to reconstruct ancient firing procedures. Two sets of firings took place in 1993 and 1997 in Batán Grande using a partially restored Formative kiln from about 800 BC, local hardwood and cow dung as fuel. A third experiment followed in 2000 after the discovery of a Middle Sicán ceramics workshop in use between ca. AD 950 and 1050 at Huaca Sialupe, where an exact replica of an ancient kiln was built from local clay, and fired with local wood and cow dung. Additionally, inverted urns found at Huaca Sialupe were tested for their potential use as furnaces for metal working. Mössbauer spectroscopy was used to compare the physical and chemical state of specimens produced in the field experiments with ancient ceramics and with specimens produced in controlled laboratory experiments.

  16. Early Pottery Making in Northern Coastal Peru. Part II: Field Firing Experiments

    International Nuclear Information System (INIS)

    Shimada, I.; Goldstein, D.; Sosa, J.; Wagner, U.

    2003-01-01

    We present data from three seasons of experimental field work designed to recreate ancient Andean coastal ceramic firing techniques. Based on the recent discovery of two different archaeological ceramic production sites in the La Leche river valley of northern coastal Peru, the opportunity arose to apply Moessbauer spectroscopy and other analytical methods to reconstruct ancient firing procedures. Two sets of firings took place in 1993 and 1997 in Batan Grande using a partially restored Formative kiln from about 800 BC, local hardwood and cow dung as fuel. A third experiment followed in 2000 after the discovery of a Middle Sican ceramics workshop in use between ca. AD 950 and 1050 at Huaca Sialupe, where an exact replica of an ancient kiln was built from local clay, and fired with local wood and cow dung. Additionally, inverted urns found at Huaca Sialupe were tested for their potential use as furnaces for metal working. Moessbauer spectroscopy was used to compare the physical and chemical state of specimens produced in the field experiments with ancient ceramics and with specimens produced in controlled laboratory experiments.

  17. Control of Earth-like magnetic fields on the transformation of ferrihydrite to hematite and goethite.

    Science.gov (United States)

    Jiang, Zhaoxia; Liu, Qingsong; Dekkers, Mark J; Barrón, Vidal; Torrent, José; Roberts, Andrew P

    2016-07-26

    Hematite and goethite are the two most abundant iron oxides in natural environments. Their formation is controlled by multiple environmental factors; therefore, their relative concentration has been used widely to indicate climatic variations. In this study, we aimed to test whether hematite and goethite growth is influenced by ambient magnetic fields of Earth-like values. Ferrihydrite was aged at 95 °C in magnetic fields ranging from ~0 to ~100 μT. Our results indicate a large influence of the applied magnetic field on hematite and goethite growth from ferrihydrite. The synthesized products are a mixture of hematite and goethite for field intensities fields favour hematite formation by accelerating ferrimagnetic ferrihydrite aggregation. Additionally, hematite particles growing in a controlled magnetic field of ~100 μT appear to be arranged in chains, which may be reduced to magnetite keeping its original configuration, therefore, the presence of magnetic particles in chains in natural sediments cannot be used as an exclusive indicator of biogenic magnetite. Hematite vs. goethite formation in our experiments is influenced by field intensity values within the range of geomagnetic field variability. Thus, geomagnetic field intensity could be a source of variation when using iron (oxyhydr-)oxide concentrations in environmental magnetism.

  18. Time-delay effects and simplified control fields in quantum Lyapunov control

    International Nuclear Information System (INIS)

    Yi, X X; Wu, S L; Wu, Chunfeng; Feng, X L; Oh, C H

    2011-01-01

    Lyapunov-based quantum control has the advantage that it is free from the measurement-induced decoherence and it includes the instantaneous information of the system in the control. The Lyapunov control is often confronted with time delay in the control fields and difficulty in practical implementations of the control. In this paper, we study the effect of time delay on the Lyapunov control and explore the possibility of replacing the control field with a pulse train or a bang-bang signal. The efficiency of the Lyapunov control is also presented through examining the convergence time of the system. These results suggest that the Lyapunov control is robust against time delay, easy to realize and effective for high-dimensional quantum systems.

  19. Quantum control mechanism analysis through field based Hamiltonian encoding

    International Nuclear Information System (INIS)

    Mitra, Abhra; Rabitz, Herschel

    2006-01-01

    Optimal control of quantum dynamics in the laboratory is proving to be increasingly successful. The control fields can be complex, and the mechanisms by which they operate have often remained obscure. Hamiltonian encoding (HE) has been proposed as a method for understanding mechanisms in quantum dynamics. In this context mechanism is defined in terms of the dominant quantum pathways leading to the final state of the controlled system. HE operates by encoding a special modulation into the Hamiltonian and decoding its signature in the dynamics to determine the dominant pathway amplitudes. Earlier work encoded the modulation directly into the Hamiltonian operators. This present work introduces the alternative scheme of field based HE, where the modulation is encoded into the control field and not directly into the Hamiltonian operators. This distinct form of modulation yields a new perspective on mechanism and is computationally faster than the earlier approach. Field based encoding is also an important step towards a laboratory based algorithm for HE as it is the only form of encoding that may be experimentally executed. HE is also extended to cover systems with noise and uncertainty and finally, a hierarchical algorithm is introduced to reveal mechanism in a stepwise fashion of ever increasing detail as desired. This new hierarchical algorithm is an improvement over earlier approaches to HE where the entire mechanism was determined in one stroke. The improvement comes from the use of less complex modulation schemes, which leads to fewer evaluations of Schroedinger's equation. A number of simulations are presented on simple systems to illustrate the new field based encoding technique for mechanism assessment

  20. The Mistra experiment for field containment code validation first results

    International Nuclear Information System (INIS)

    Caron-Charles, M.; Blumenfeld, L.

    2001-01-01

    The MISTRA facility is a large scale experiment, designed for the purpose of thermal-hydraulics multi-D codes validation. A short description of the facility, the set up of the instrumentation and the test program are presented. Then, the first experimental results, studying helium injection in the containment and their calculations are detailed. (author)

  1. International Field Experiences Promote Professional Development for Sustainability Leaders

    Science.gov (United States)

    Hull, R. Bruce; Kimmel, Courtney; Robertson, David P.; Mortimer, Michael

    2016-01-01

    Purpose: This paper aims to describe, explain and evaluate a graduate education program that provides international project experiences and builds competencies related to collaborative problem-solving, cultural capacity to work globally and sustainable development. Design/methodology/approach: Qualitative analysis of survey data from 28 students…

  2. Luck or cheating? A field experiment on honesty with children

    NARCIS (Netherlands)

    Bucciol, A.; Piovesan, M.

    2008-01-01

    We ran an experiment with children to study the development of honesty with age. We asked each child to toss a fair coin in private and to record the outcome (white or black) in a paper sheet. We rewarded only those who reported white. We found a fraction of reported whites signifi cantly larger

  3. Ideas on a generic control systems based on the experience on the 4 LEP experiments control system

    International Nuclear Information System (INIS)

    Barillere, R.; Le Goff, J.M.; Milcent, H.; Stampfli, R.

    1992-01-01

    Most of the large slow control systems in the LEP collider experiments are distributed heterogeneous and multi-standard. But in spite of the appearances, they have a lot in common. From our direct experience on the L-3 slow control system and from the informations we obtained on the 3 other LEP experiments control systems we have come to the conclusion that it should be possible to build a Generic Control Package from which any control system could be derived. This software package is entirely based on relational databases and is intended to provide all the necessary tools to build a modular, coherent, easy to update and to maintain control system. Among other things this package should include user friendly interfaces, expert systems, and powerful graphic monitoring and control tools. This paper will present our general ideas about the realization of such a package. (author)

  4. Thermal and Field Enhanced Photoemission Comparison of Theory to Experiment

    CERN Document Server

    Lynn-Jensen, Kevin

    2004-01-01

    Photocathodes are a critical component of high-gain FEL’s and the analysis of their emission is complex. Relating their performance under laboratory conditions to conditions of an rf photoinjector is difficult. Useful models must account for cathode surface conditions and material properties, as well as drive laser parameters. We have developed a time-dependent model accounting for the effects of laser heating and thermal propagation on photoemission. It accounts for surface conditions (coating, field enhancement, reflectivity), laser parameters (duration, intensity, wavelength), and material characteristics (reflectivity, laser penetration depth, scattering rates) to predict current distribution and quantum efficiency. The applicatIon will focus on photoemission from metals and, in particular, dispenser photocathodes: the later introduces complications such as coverage non-uniformity and field enhancement. The performance of experimentally characterized photocathodes will be extrapolated to 0.1 - 1 nC bunch...

  5. Field error reduction experiment on the REPUTE-1 RFP device

    International Nuclear Information System (INIS)

    Toyama, H.; Shinohara, S.; Yamagishi, K.

    1989-01-01

    The vacuum chamber of the RFP device REPUTE-1 is a welded structure using 18 sets of 1 mm thick Inconel bellows (inner minor radius 22 cm) and 2.4 mm thick port segments arranged in toroidal geometry as shown in Fig. 1. The vacuum chamber is surrounded by 5 mm thick stainless steel shells. The time constant of the shell is 1 ms for vertical field penetration. The pulse length in REPUTE-1 is so far 3.2 ms (about 3 times longer than shell skin time). The port bypass plates have been attached as shown in Fig. 2 to reduce field errors so that the pulse length becomes longer and the loop voltage becomes lower. (author) 5 refs., 4 figs

  6. Laboratory and field experience with rim ditch dewatering of MFT

    Energy Technology Data Exchange (ETDEWEB)

    Demoz, A.; Mikula, R. [Natural Resources Canada, Devon, AB (Canada). CANMET Western Research Centre; Lahaie, R. [Syncrude Canada Ltd., Edmonton, AB (Canada)

    2010-07-01

    This PowerPoint presentation described a rim ditch method of dewatering mature fine tailings (MFT). Polymer additions were used to strengthen the MFT and to decrease the capillary suction time (CST). Laboratory and field-scale studies were conducted to demonstrate the dewatering method. The flocculants were added in a Komax inline mixer. Polymers were then injected into the tailings. The mixing processes were optimized in a series of laboratory studies and then demonstrated in the field tests. The tests showed that CST and high dewatering rates were consistently maintained using the method. MFT feeds were also consistent. Release water quality was improved using the method. The large-scale test site is now being monitored for compliance with Directive 74. tabs., figs.

  7. In Silico Pooling of ChIP-seq Control Experiments

    Science.gov (United States)

    Sun, Guannan; Srinivasan, Rajini; Lopez-Anido, Camila; Hung, Holly A.; Svaren, John; Keleş, Sündüz

    2014-01-01

    As next generation sequencing technologies are becoming more economical, large-scale ChIP-seq studies are enabling the investigation of the roles of transcription factor binding and epigenome on phenotypic variation. Studying such variation requires individual level ChIP-seq experiments. Standard designs for ChIP-seq experiments employ a paired control per ChIP-seq sample. Genomic coverage for control experiments is often sacrificed to increase the resources for ChIP samples. However, the quality of ChIP-enriched regions identifiable from a ChIP-seq experiment depends on the quality and the coverage of the control experiments. Insufficient coverage leads to loss of power in detecting enrichment. We investigate the effect of in silico pooling of control samples within multiple biological replicates, multiple treatment conditions, and multiple cell lines and tissues across multiple datasets with varying levels of genomic coverage. Our computational studies suggest guidelines for performing in silico pooling of control experiments. Using vast amounts of ENCODE data, we show that pairwise correlations between control samples originating from multiple biological replicates, treatments, and cell lines/tissues can be grouped into two classes representing whether or not in silico pooling leads to power gain in detecting enrichment between the ChIP and the control samples. Our findings have important implications for multiplexing samples. PMID:25380244

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

    Science.gov (United States)

    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.

  9. 4D experience on Girassol Field block 17, Angola

    Energy Technology Data Exchange (ETDEWEB)

    Lefeuvre, F.; Brechet, E.; Bertini, F.; Jourdan, J.M.; Cassou, G. [TOTAL S.A., Luanda (Angola); Dubucq, D. [TOTAL Angola, Luanda (Angola)

    2004-07-01

    The Girassol field is located in Angolan deep water of Block 17 and consists of large vertically stacked turbidities complexes. The reservoir extends over approximately 200 km{sup 2} and water depth ranges between 1300 and 1400 meters. In that context High Resolution 3D seismic became the most valuable tool to describe and monitor the reservoir. The field development plan took into account, through re-injection of the gas into the reservoir, Total environmental policy imposing the recycling of production gas. Monitoring of this injection was the main reason to shoot the first High Resolution 4D extremely early in the life of field. Despite the complexity of interpretation due to complex fluid situation and pressure effect, the results went way beyond expectations as the 4D images are of very high quality. Data has also been used to update and refine the reservoir flow model as well as to help deciding on the location of latest development wells. Other repeat surveys are scheduled, the next one before the end of 2004. The ultimate goal which we hope to reach in the very near future will be to use seismic-derived saturation and pressure changes to constrain the reservoir model during the history matching process. (author)

  10. Information barriers and social stratification in higher education: evidence from a field experiment.

    Science.gov (United States)

    Abbiati, Giovanni; Argentin, Gianluca; Barone, Carlo; Schizzerotto, Antonio

    2017-11-29

    Our contribution assesses the role of information barriers for patterns of participation in Higher Education (HE) and the related social inequalities. For this purpose, we developed a large-scale clustered randomised experiment involving over 9,000 high school seniors from 62 Italian schools. We designed a counseling intervention to correct student misperceptions of the profitability of HE, that is, the costs, economic returns and chances of success of investments in different tertiary programs. We employed a longitudinal survey to test whether treated students' educational trajectories evolved differently relative to a control group. We find that, overall, treated students enrolled less often in less remunerative fields of study in favour of postsecondary vocational programmes. Most importantly, this effect varied substantially by parental social class and level of education. The shift towards vocational programmes was mainly due to the offspring of low-educated parents; in contrast, children of tertiary graduates increased their participation in more rewarding university fields. Similarly, the redistribution from weak fields to vocational programmes mainly involved the children of the petty bourgeoisie and the working class, while upper class students invested in more rewarding university fields. We argue that the status-maintenance model proposed by Breen and Goldthorpe can explain these socially differentiated treatment effects. Overall, our results challenge the claim that student misperceptions contribute to horizontal inequalities in access to HE. © London School of Economics and Political Science 2017.

  11. Ethics commentary: subjects of knowledge and control in field primatology.

    Science.gov (United States)

    Malone, N M; Fuentes, A; White, F J

    2010-09-01

    Our primate kin are routinely displaced from their habitats, hunted for meat, captured for trade, housed in zoos, made to perform for our entertainment, and used as subjects in biomedical testing. They are also the subjects of research inquiries by field primatologists. In this article, we place primate field studies on a continuum of human and alloprimate relationships as a heuristic device to explore the unifying ethical implications of such inter-relationships, as well as address specific ethical challenges arising from common research protocols "in the field" (e.g. risks associated with habituation, disease transmission, invasive collection of biological samples, etc.). Additionally, we question the widespread deployment of conservation- and/or local economic development-based justifications for field-based primatological pursuits. Informed by decades of combined fieldwork experience in Indonesia and the Democratic Republic of Congo, we demonstrate the process by which the adherence to a particular ethical calculus can lead to unregulated and ethically problematic research agendas. In conclusion, we offer several suggestions to consider in the establishment of a formalized code of ethics for field primatology. (c) 2010 Wiley-Liss, Inc.

  12. A control system for a free electron laser experiment

    International Nuclear Information System (INIS)

    Giove, D.

    1992-01-01

    The general layout of a control and data acquisition system for a Free Electron Laser experiment will be discussed. Some general considerations about the requirements and the architecture of the whole system will be developed. (author)

  13. Alkylation of Chlorobenzene. An Experiment Illustrating Kinetic versus Thermodynamic Control.

    Science.gov (United States)

    Kolb, Kenneth; And Others

    1988-01-01

    Describes an experiment which illustrates the kinetic versus thermodynamic control of chemical reactions for organic chemistry students. Considers the laboratory procedures including the isolation of both the kinetic and thermodynamic products. (CW)

  14. Modelling the Grimsel migration field experiments at PSI

    International Nuclear Information System (INIS)

    Heer, W.

    1997-01-01

    For several years tracer migration experiments have been performed at Nagra's Grimsel Test Site as a joint undertaking of Nagra, PNC and PSI. The aims of modelling the migration experiments are (1) to better understand the nuclide transport through crystalline rock; (2) to gain information on validity of methods and correlating parameters; (3) to improve models for safety assessments. The PSI modelling results, presented here, show a consistent picture for the investigated tracers (the non-sorbing uranine, the weakly sorbing sodium, the moderately sorbing strontium and the more strongly sorbing cesium). They represent an important step in building up confidence in safety assessments for radioactive waste repositories. (author) 5 figs., 1 tab., 12 refs

  15. Using Field Experiments to Change the Template of How We Teach Economics

    Science.gov (United States)

    List, John A.

    2014-01-01

    In this article, the author explains why field experiments can improve what we teach and how we teach economics. Economists no longer operate as passive observers of economic phenomena. Instead, they participate actively in the research process by collecting data from field experiments to investigate the economics of everyday life. This change can…

  16. Community-Based Field Experiences in Teacher Education: Possibilities for a Pedagogical Third Space

    Science.gov (United States)

    Hallman, Heidi L.

    2012-01-01

    The present article discusses the importance of community-based field experiences as a feature of teacher education programs. Through a qualitative case study, prospective teachers' work with homeless youth in an after-school initiative is presented. Framing community-based field experiences in teacher education through "third space" theory, the…

  17. An experience in the field of training in radiological protection

    International Nuclear Information System (INIS)

    Fluchere, J.

    1983-01-01

    The author, a former head of an EdF training center, gives his thoughts on the training of EdF nuclear power plant radiation workers whose number was increased fourfold in 6 years and whose initial qualifications varied considerably. The orientation already taken and the directions that experience has suggested to be promising are indicated. Attention is also drawn on psychological problems that should be taken into consideration in order to work efficiently [fr

  18. Poloidal field system design for the ZT-H reversed field pinch experiment

    International Nuclear Information System (INIS)

    Schoenberg, K.F.; Gribble, R.F.; Linton, T.W.; Reass, W.R.

    1983-01-01

    This report discusses each of the following areas: (1) equilibrium specification, (2) the equilibrium winding, (3) the magnetizing winding, (4) numerical poloidal field system analysis, (5) coil cross section, turns, minimum field error, (6) coil stresses and cooling, (7) the upper structure, (8) the loads, (9) boundary conditions and method of analysis, and (10) design description

  19. Viking satellite program - preliminary results from the APL Magnetic Field Experiment

    International Nuclear Information System (INIS)

    Potemra, T.A.; Zanetti, L.J.; Erlandson, R.E.; Gustafsson, G.; Acuna, M.H.; NASA, Goddard Space Flight Center, Greenbelt, MD)

    1986-01-01

    Sweden's Viking satellite, launched in February 1986, has been conducting plasma process observations in the earth magnetosphere and auroral regions; the U.S.-supplied APL Magnetic Field Experiment aboard Viking is used to determine field-aligned Birkeland current characteristics in previously unsampled regions of near-earth space. The Magnetic Field Experiment has an equivalent spatial resolution of 12 m in the auroral ionosphere when making measurements near apogee. The purposes of Viking's other instruments and their relationship to the Magnetic Field Experiment are discussed

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

    Science.gov (United States)

    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…

  1. Formation of toroidal pre-heat plasma without residual magnetic field for high-beta pinch experiments

    International Nuclear Information System (INIS)

    Ikeda, Nagayasu; Tamaru, Ken; Nagata, Akiyoshi.

    1979-01-01

    Formation of toroidal pre-heat plasma was studied. The pre-heat plasma without residual magnetic field was made by chopping the current for pre-heat, A small toroidal-pinch system was used for the experiment. The magnetic field was measured with a magnetic probe. One turn loop was used for the measurement of the toroidal one-turn electric field. A pair of Rogoski coil was used for the measurement of plasma current. The dependence of residual magnetic field on chopping time was measured. By fast chopping of the primary current in the pre-heating circuit, the poloidal magnetic field was reduced to several percent within 5 microsecond. After chopping, no instability was observed in the principal discharge plasma produced within several microsecond. As the conclusion, it can be said that the control of residual field can be made by current chopping. (Kato, T.)

  2. Electron temperature diagnostics in the RFX reversed field pinch experiment

    International Nuclear Information System (INIS)

    Bartiromo, R.; Carraro, L.; Marrelli, L.; Murari, A.; Pasqualotto, R.; Puiatti, M.E.; Scarin, P.; Valisa, M.; Franz, P.; Martin, P.; Zabeo, L.

    2000-01-01

    The paper presents an integrated approach to the problem of electron temperature diagnostics of the plasma in a reversed field pinch. Three different methods, sampling different portions of the electron distribution function, are adopted, namely Thomson scattering, soft X-ray spectroscopy by pulse-height analysis and filtered soft X-ray intensity ratio. A careful analysis of the different sources of systematic errors is performed and a novel statistical approach is adopted to mutually validate the three independent measurements. A satisfactory agreement is obtained over a large range of experimental conditions, indicating that in the plasma core the energy distribution function is well represented by a maxwellian. (author)

  3. First experiments probing the collision of parallel magnetic fields using laser-produced plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Rosenberg, M. J., E-mail: mros@lle.rochester.edu; Li, C. K.; Séguin, F. H.; Frenje, J. A.; Petrasso, R. D. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Fox, W. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Igumenshchev, I.; Stoeckl, C.; Glebov, V. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States); Town, R. P. J. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2015-04-15

    Novel experiments to study the strongly-driven collision of parallel magnetic fields in β ∼ 10, laser-produced plasmas have been conducted using monoenergetic proton radiography. These experiments were designed to probe the process of magnetic flux pileup, which has been identified in prior laser-plasma experiments as a key physical mechanism in the reconnection of anti-parallel magnetic fields when the reconnection inflow is dominated by strong plasma flows. In the present experiments using colliding plasmas carrying parallel magnetic fields, the magnetic flux is found to be conserved and slightly compressed in the collision region. Two-dimensional (2D) particle-in-cell simulations predict a stronger flux compression and amplification of the magnetic field strength, and this discrepancy is attributed to the three-dimensional (3D) collision geometry. Future experiments may drive a stronger collision and further explore flux pileup in the context of the strongly-driven interaction of magnetic fields.

  4. Wave field synthesis, adaptive wave field synthesis and ambisonics using decentralized transformed control: Potential applications to sound field reproduction and active noise control

    Science.gov (United States)

    Gauthier, Philippe-Aubert; Berry, Alain; Woszczyk, Wieslaw

    2005-09-01

    Sound field reproduction finds applications in listening to prerecorded music or in synthesizing virtual acoustics. The objective is to recreate a sound field in a listening environment. Wave field synthesis (WFS) is a known open-loop technology which assumes that the reproduction environment is anechoic. Classical WFS, therefore, does not perform well in a real reproduction space such as room. Previous work has suggested that it is physically possible to reproduce a progressive wave field in-room situation using active control approaches. In this paper, a formulation of adaptive wave field synthesis (AWFS) introduces practical possibilities for an adaptive sound field reproduction combining WFS and active control (with WFS departure penalization) with a limited number of error sensors. AWFS includes WFS and closed-loop ``Ambisonics'' as limiting cases. This leads to the modification of the multichannel filtered-reference least-mean-square (FXLMS) and the filtered-error LMS (FELMS) adaptive algorithms for AWFS. Decentralization of AWFS for sound field reproduction is introduced on the basis of sources' and sensors' radiation modes. Such decoupling may lead to decentralized control of source strength distributions and may reduce computational burden of the FXLMS and the FELMS algorithms used for AWFS. [Work funded by NSERC, NATEQ, Université de Sherbrooke and VRQ.] Ultrasound/Bioresponse to

  5. A Shared Compliance Control for Application in High Radiation Fields

    International Nuclear Information System (INIS)

    Ahn, Sung Ho; Jung, Hoan Sung; Lee, Kye Hong; Kim, Young Ki; Kim, Hark Rho

    2005-01-01

    Bilateral control systems present a technical alternative for intelligent robotic systems performing dexterous tasks in unstructured environments such as a nuclear facility, outer space and underwater. A shared compliance control scheme is proposed for application in high radiation fields in which the force sensor can not be installed because of a radiation effect. A position difference between the master system and the slave system is treated as an equivalent contact force and used for an input to the compliance controller. The compliance controller is implemented by a first order low pass filter and it modifies the position of the master to the reference position. Thus the compliance control task is shared by both the human operator's direct manual control and the autonomous compliance control of the slave system. Consequently, the position of a slave system tracks well the reference position and the compliance of the slave system is autonomously controlled in a contact condition. The simulation results show the excellence of the proposed scheme

  6. Coherent feedback control of multipartite quantum entanglement for optical fields

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Zhihui; Jia, Xiaojun; Xie, Changde; Peng, Kunchi [State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Opto-Electronics, Shanxi University, Taiyuan, 030006 (China)

    2011-12-15

    Coherent feedback control (CFC) of multipartite optical entangled states produced by a nondegenerate optical parametric amplifier is theoretically studied. The features of the quantum correlations of amplitude and phase quadratures among more than two entangled optical modes can be controlled by tuning the transmissivity of the optical beam splitter in the CFC loop. The physical conditions to enhance continuous variable multipartite entanglement of optical fields utilizing the CFC loop are obtained. The numeric calculations based on feasible physical parameters of realistic systems provide direct references for the design of experimental devices.

  7. Temptation and productivity: a field experiment with children

    NARCIS (Netherlands)

    Bucciol, A.; Houser, D.; Piovesan, M.

    2011-01-01

    Substantial evidence from psychology suggests that resisting temptation (exercising self-control) in one domain subsequently reduces one's capacity to regulate behavior in other domains. A reason is that people have limited self-regulatory resources, and self-regulatory failure occurs when these

  8. Overview of results from the MST reversed field pinch experiment

    International Nuclear Information System (INIS)

    Sarff, J.S.; Almagri, A.F.; Anderson, J.K.; Borchardt, M.; Carmody, D.; Caspary, K.; Chapman, B.E.; Den Hartog, D.J.; Duff, J.; Eilerman, S.; Falkowski, A.; Forest, C.B.; Goetz, J.A.; Holly, D.J.; Kim, J.-H.; King, J.; Ko, J.; Koliner, J.; Kumar, S.; Lee, J.D.

    2013-01-01

    An overview of recent results from the MST programme on physics important for the advancement of the reversed field pinch (RFP) as well as for improved understanding of toroidal magnetic confinement more generally is reported. Evidence for the classical confinement of ions in the RFP is provided by analysis of impurity ions and energetic ions created by 1 MW neutral beam injection (NBI). The first appearance of energetic-particle-driven modes by NBI in a RFP plasma is described. MST plasmas robustly access the quasi-single-helicity state that has commonalities to the stellarator and ‘snake’ formation in tokamaks. In MST the dominant mode grows to 8% of the axisymmetric field strength, while the remaining modes are reduced. Predictive capability for tearing mode behaviour has been improved through nonlinear, 3D, resistive magnetohydrodynamic computation using the measured resistivity profile and Lundquist number, which reproduces the sawtooth cycle dynamics. Experimental evidence and computational analysis indicates two-fluid effects, e.g., Hall physics and gyro-viscosity, are needed to understand the coupling of parallel momentum transport and current profile relaxation. Large Reynolds and Maxwell stresses, plus separately measured kinetic stress, indicate an intricate momentum balance and a possible origin for MST's intrinsic plasma rotation. Gyrokinetic analysis indicates that micro-tearing modes can be unstable at high beta, with a critical gradient for the electron temperature that is larger than for tokamak plasmas by roughly the aspect ratio. (paper)

  9. Pesticide uptake in potatoes: model and field experiments.

    Science.gov (United States)

    Juraske, Ronnie; Vivas, Carmen S Mosquera; Velásquez, Alexander Erazo; Santos, Glenda García; Moreno, Mónica B Berdugo; Gomez, Jaime Diaz; Binder, Claudia R; Hellweg, Stefanie; Dallos, Jairo A Guerrero

    2011-01-15

    A dynamic model for uptake of pesticides in potatoes is presented and evaluated with measurements performed within a field trial in the region of Boyacá, Colombia. The model takes into account the time between pesticide applications and harvest, the time between harvest and consumption, the amount of spray deposition on soil surface, mobility and degradation of pesticide in soil, diffusive uptake and persistence due to crop growth and metabolism in plant material, and loss due to food processing. Food processing steps included were cleaning, washing, storing, and cooking. Pesticide concentrations were measured periodically in soil and potato samples from the beginning of tuber formation until harvest. The model was able to predict the magnitude and temporal profile of the experimentally derived pesticide concentrations well, with all measurements falling within the 90% confidence interval. The fraction of chlorpyrifos applied on the field during plant cultivation that eventually is ingested by the consumer is on average 10(-4)-10(-7), depending on the time between pesticide application and ingestion and the processing step considered.

  10. Localized damage in soft rock: experiments with field measurement techniques

    International Nuclear Information System (INIS)

    Nguyen, T.L.

    2011-01-01

    The research presented in this thesis concerns, firstly, an experimental study on the process of fracture in uniaxial compression of rock samples containing narrow, rectilinear notches inclined with respect to the axis of loading. Secondly, we study the evolution of shear strain localisation towards fracturing and failure in specimens of the same materials with a particular geometry, involving two rounded notches. This geometry, inspired by the work of Meuwissen et al. (1998) for tension tests on metals, promotes the localisation of shear strain in simple compression before fracture. Two different materials were studied: a natural rock of volcanic origin (Neapolitan Tuff) and an artificial 'roc' (CPIR09). In the studies presented, three full-field measurement techniques have been employed in combination: (i) the Digital Image Correlation (DIC), for measurement of kinematic fields at a sample's surface; (ii)acoustic Emission measurements (AE) and AE source location, to follow the evolution of damage in samples during loading; (iii) X-ray tomography (pre-and post-mortem studies), to characterise preexisting defects and discontinuities in the specimens and to better understand the fracturing in 3D. (author)

  11. Field experience with a mobile tomographic nondestructive assay system

    International Nuclear Information System (INIS)

    Prettyman, T.H.; Betts, S.E.; Taggart, D.P.; Estep, R.J.; Nicholas, N.J.; Lucas, M.C.; Harlan, R.A.

    1995-01-01

    A mobile tomographic gamma-ray scanner (TGS) developed by Los Alamos National Laboratory was recently demonstrated at the Rocky Flats Environmental Technology Site and is currently in use at Los Alamos waste storage areas. The scanner was developed to assay radionuclides in low-level, transuranic, and mixed waste in containers ranging in size from 2 ft 3 boxes to 83-gallon overpacks. The tomographic imaging capability provides a complete correction for source distribution and matrix attenuation effects, enabling accurate assays of Pu-239 and other gamma-ray emitting isotopes. In addition, the system can reliably detect self-absorbing material such as plutonium metal shot, and can correct for bias caused by self-absorption. The system can be quickly configured to execute far-field scans, segmented gamma-ray scans, and a host of intermediate scanning protocols, enabling higher throughput (up to 20 drums per 8-hour shift). In this paper, we will report on the results of field trials of the mobile system at Rocky Flats and Los Alamos. Assay accuracy is confirmed for cases in which TGS assays can be compared with assays (e.g. with calorimetry) of individual packages within the drums. The mobile tomographic technology is expected to considerably reduce characterization costs at DOE production and environmental technology sites

  12. The 1987 Federal field exercise: The DOE experience

    International Nuclear Information System (INIS)

    Adler, M.V.; Gant, K.S.

    1989-06-01

    The second full-scale field exercise of the Federal Radiological Emergency Response Plan (FRERP) was held at the Zion Nuclear Power Station, Zion, Illinois, in June 1987. The exercise incorporated the annual compliance exercise for the Zion plant and involved the operating utility, Commonwealth Edison Company, the states of Illinois and Wisconsin, local governments, volunteer groups, and representatives from 12 federal agencies. The 3-day exercise was played from many locations in the Zion area; Springfield, Illinois; Madison, Wisconsin; and Washington, DC. Approximately 1000 people participated in the exercise, which used a scenario in which an accident at the plant resulted in the release of radioactive material outside the plant boundary. The US Department of Energy (DOE) had major responsibilities during the planning, playing, and critiquing of the exercise; these functions are outlined in the report. This document describes the DOE participation in the planning and response during the exercise. During a radiological emergency, the FRERP gives DOE the responsibility for coordinating the federal radiological monitoring and assessment activities in support of the states and the cognizant federal agency. At Zion, a self-sufficient Federal Radiological Monitoring and Assessment Center was established by DOE at a nearby fairground in which over 200 people from DOE, the two states, and other federal agencies participated. Before the field exercise, a tabletop exercise and a dry run were held for training purposes. 5 refs., 6 figs

  13. Continuous control of spin polarization using a magnetic field

    Science.gov (United States)

    Gifford, J. A.; Zhao, G. J.; Li, B. C.; Tracy, Brian D.; Zhang, J.; Kim, D. R.; Smith, David J.; Chen, T. Y.

    2016-05-01

    The giant magnetoresistance (GMR) of a point contact between a Co/Cu multilayer and a superconductor tip varies for different bias voltage. Direct measurement of spin polarization by Andreev reflection spectroscopy reveals that the GMR change is due to a change in spin polarization. This work demonstrates that the GMR structure can be utilized as a spin source and that the spin polarization can be continuously controlled by using an external magnetic field.

  14. Continuous control of spin polarization using a magnetic field

    International Nuclear Information System (INIS)

    Gifford, J. A.; Zhao, G. J.; Li, B. C.; Tracy, Brian D.; Zhang, J.; Kim, D. R.; Smith, David J.; Chen, T. Y.

    2016-01-01

    The giant magnetoresistance (GMR) of a point contact between a Co/Cu multilayer and a superconductor tip varies for different bias voltage. Direct measurement of spin polarization by Andreev reflection spectroscopy reveals that the GMR change is due to a change in spin polarization. This work demonstrates that the GMR structure can be utilized as a spin source and that the spin polarization can be continuously controlled by using an external magnetic field.

  15. Continuous control of spin polarization using a magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Gifford, J. A.; Zhao, G. J.; Li, B. C.; Tracy, Brian D.; Zhang, J.; Kim, D. R.; Smith, David J.; Chen, T. Y., E-mail: tingyong.chen@asu.edu [Department of Physics, Arizona State University, Tempe, Arizona 85287 (United States)

    2016-05-23

    The giant magnetoresistance (GMR) of a point contact between a Co/Cu multilayer and a superconductor tip varies for different bias voltage. Direct measurement of spin polarization by Andreev reflection spectroscopy reveals that the GMR change is due to a change in spin polarization. This work demonstrates that the GMR structure can be utilized as a spin source and that the spin polarization can be continuously controlled by using an external magnetic field.

  16. The ITER poloidal field system: control and power supplies

    International Nuclear Information System (INIS)

    Mondino, P.L.; Benfatto, I.; Gribov, Y.; Matsukawa, M.; Odajima, K.; Portone, A.; Roshal, A.; Bareyt, B.; Bertolini, E.; Bottereau, J.M.; Huart, M.; Maschio, A.; Bulgakov, S.; Kuchinski, V.

    1995-01-01

    The paper reports the preliminary scenario of the ITER Poloidal Field (PF) system operation, the method used to evaluate the installed power, the basic structure of the circuits and finally the concepts of the preliminary design of control and power supply. The superconducting coils are energized from the HV Grid with conventional AC/DC converters. R and D is required for circuit breakers, make switches and resistors, the basic components of both the switching networks and the discharge circuits. (orig.)

  17. Microcredit, family planning programs, and contraceptive behavior: evidence from a field experiment in Ethiopia.

    Science.gov (United States)

    Desai, Jaikishan; Tarozzi, Alessandro

    2011-05-01

    The impact of community-based family planning programs and access to credit on contraceptive use, fertility, and family size preferences has not been established conclusively in the literature. We provide additional evidence on the possible effect of such programs by describing the results of a randomized field experiment whose main purpose was to increase the use of contraceptive methods in rural areas of Ethiopia. In the experiment, administrative areas were randomly allocated to one of three intervention groups or to a fourth control group. In the first intervention group, both credit and family planning services were provided and the credit officers also provided information on family planning. Only credit or family planning services, but not both, were provided in the other two intervention groups, while areas in the control group received neither type of service. Using pre- and post-intervention surveys, we find that neither type of program, combined or in isolation, led to an increase in contraceptive use that is significantly greater than that observed in the control group. We conjecture that the lack of impact has much to do with the mismatch between women's preferred contraceptive method (injectibles) and the contraceptives provided by community-based agents (pills and condoms).

  18. Randomized Controlled Trial of Teaching Methods: Do Classroom Experiments Improve Economic Education in High Schools?

    Science.gov (United States)

    Eisenkopf, Gerald; Sulser, Pascal A.

    2016-01-01

    The authors present results from a comprehensive field experiment at Swiss high schools in which they compare the effectiveness of teaching methods in economics. They randomly assigned classes into an experimental and a conventional teaching group, or a control group that received no specific instruction. Both teaching treatments improve economic…

  19. An e-Learning System with MR for Experiments Involving Circuit Construction to Control a Robot

    Science.gov (United States)

    Takemura, Atsushi

    2016-01-01

    This paper proposes a novel e-Learning system for technological experiments involving electronic circuit-construction and controlling robot motion that are necessary in the field of technology. The proposed system performs automated recognition of circuit images transmitted from individual learners and automatically supplies the learner with…

  20. Experimental Characterization of Piezoelectric Radial Field Diaphragms for Fluidic Control

    Science.gov (United States)

    Bryant, R. G.; Kavli, S. E.; Thomas, R. A., Jr.; Darji, K. J.; Mossi, K. M.

    2004-01-01

    NASA has recently developed a new piezoelectric actuator, the Radial Field Diaphragm or RFD. This actuator uses a radially-directed electric field to generate concentric out-of-plane (Z-axis) motion that allows this packaged device to be used as a pump or valve diaphragm. In order to efficiently use this new active device, experimental determination of pressure, flow rate, mechanical work, power consumption and overall efficiency needs to be determined by actually building a pump. However, without an optimized pump design, it is difficult to assess the quality of the data, as these results are inherent to the actual pump. Hence, separate experiments must be conducted in order to generate independent results to help guide the design criteria and pump quality. This paper focuses on the experiments used to generate the RFD's operational parameters and then compares these results to the experimentally determined results of several types of ball pumps. Also discussed are how errors are inherently introduced into the experiments, the pump design, experimental hardware and their effects on the overall system efficiency.

  1. Multibeam smart antenna field trial experiments in mobile radio environments

    Science.gov (United States)

    Perini, Patrick

    1996-01-01

    Several types of high gain multibeam antennas were tested and compared to traditional sector and omni antennas in various mobile radio environments. A vehicle equipped with a mobile transmitter drove in several mobile radio environments while the received signal strength (RSS) was recorded on multiple antenna channels attached to multibeam, sector and omni directional antennas. The RSS data recorded included the fast (rayleigh) fading and was averaged into local means based on the mobile's position/speed. Description of the experiment and analysis of the gain improvement, average RSS, diversity gain are presented.

  2. An Overview of the First International Satellite Land Surface Climatology Project (ISLSCP) Field Experiment (FIFE)

    Science.gov (United States)

    Sellers, P. J.; Hall, F. G.; Asrar, G.; Strebel, D. E.; Murphy, R. E.

    1992-11-01

    In the summer of 1983 a group of scientists working in the fields of meteorology, biology, and remote sensing met to discuss methods for modeling and observing land-surface—atmosphere interactions on regional and global scales. They concluded, first, that the existing climate models contained poor representations of the processes controlling the exchanges of energy, water, heat, and carbon between the land surface and the atmosphere and, second, that satellite remote sensing had been underutilized as a means of specifying global fields of the governing biophysical parameters. Accordingly, a multiscale, multidisciplinary experiment, FIFE, was initiated to address these two issues. The objectives of FIFE were specified as follows: (1) Upscale integration of models: The experiment was designed to test the soil-plant-atmosphere models developed by biometeorologists for small-scale applications (millimeters to meters) and to develop methods to apply them at the larger scales (kilometers) appropriate to atmospheric models and satellite remote sensing. (2) Application of satellite remote sensing: Even if the first goal were achieved to yield a "perfect" model of vegetation-atmosphere exchanges, it would have very limited applications without a global observing system for initialization and validation. As a result, the experiment was tasked with exploring methods for using satellite data to quantify important biophysical states and rates for model input. The experiment was centered on a 15 × 15 km grassland site near Manhattan, Kansas. This area became the focus for an extended monitoring program of satellite, meteorological, biophysical, and hydrological data acquisition from early 1987 through October 1989 and a series of 12- to 20-day intensive field campaigns (IFCs), four in 1987 and one in 1989. During the IFCs the fluxes of heat, moisture, carbon dioxide, and radiation were measured with surface and airborne equipment in coordination with measurements of surface

  3. Influence of the mode of deformation on recrystallisation behaviour of titanium through experiments, mean field theory and phase field model

    Science.gov (United States)

    Athreya, C. N.; Mukilventhan, A.; Suwas, Satyam; Vedantam, Srikanth; Subramanya Sarma, V.

    2018-04-01

    The influence of the mode of deformation on recrystallisation behaviour of Ti was studied by experiments and modelling. Ti samples were deformed through torsion and rolling to the same equivalent strain of 0.5. The deformed samples were annealed at different temperatures for different time durations and the recrystallisation kinetics were compared. Recrystallisation is found to be faster in the rolled samples compared to the torsion deformed samples. This is attributed to the differences in stored energy and number of nuclei per unit area in the two modes of deformation. Considering decay in stored energy during recrystallisation, the grain boundary mobility was estimated through a mean field model. The activation energy for recrystallisation obtained from experiments matched with the activation energy for grain boundary migration obtained from mobility calculation. A multi-phase field model (with mobility estimated from the mean field model as a constitutive input) was used to simulate the kinetics, microstructure and texture evolution. The recrystallisation kinetics and grain size distributions obtained from experiments matched reasonably well with the phase field simulations. The recrystallisation texture predicted through phase field simulations compares well with experiments though few additional texture components are present in simulations. This is attributed to the anisotropy in grain boundary mobility, which is not accounted for in the present study.

  4. Experiment of Wireless Sensor Network to Monitor Field Data

    Directory of Open Access Journals (Sweden)

    Kwang Sik Kim

    2009-08-01

    Full Text Available Recently the mobile wireless network has been drastically enhanced and one of the most efficient ways to realize the ubiquitous network will be to develop the converged network by integrating the mobile wireless network with other IP fixed network like NGN (Next Generation Network. So in this paper the term of the wireless ubiquitous network is used to describe this approach. In this paper, first, the wireless ubiquitous network architecture is described based on IMS which has been standardized by 3GPP (3rd Generation Partnership Program. Next, the field data collection system to match the satellite data using location information is proposed based on the concept of the wireless ubiquitous network architecture. The purpose of the proposed system is to provide more accurate analyzing method with the researchers in the remote sensing area.

  5. Experience with a distributed computing system for magnetic field analysis

    International Nuclear Information System (INIS)

    Newman, M.J.

    1978-08-01

    The development of a general purpose computer system, THESEUS, is described the initial use for which has been magnetic field analysis. The system involves several computers connected by data links. Some are small computers with interactive graphics facilities and limited analysis capabilities, and others are large computers for batch execution of analysis programs with heavy processor demands. The system is highly modular for easy extension and highly portable for transfer to different computers. It can easily be adapted for a completely different application. It provides a highly efficient and flexible interface between magnet designers and specialised analysis programs. Both the advantages and problems experienced are highlighted, together with a mention of possible future developments. (U.K.)

  6. Mixed species flocking of tits (Parus spp.): a field experiment.

    Science.gov (United States)

    Székely, T; Szép, T; Juhász, T

    1989-03-01

    We tested two general models of flocking behaviour, namely the antipredation model and foraging efficiency model on mixed-species tit flocks (Parus spp.). After food addition the size of mixed-species flocks was significantly less than in the control samples. In the presence of extra food significantly more birds were observed either in monospecific flocks or solitary, than during the control observations. In the presence of a living predator the birds foraged in larger mixed-specifies flocks than during the control observations. In addition, the social behaviour of Great Spotted Woodpecker, Middle Spotted Woodpecker and Nuthatch shifted to mixed-specific flocking. The size of monospecific flocks was independent of both treatments. The density of birds increased significantly after food addition, while in the predator presence the birds tended to leave the forest. These results support the view that both the antipredation model and foraging efficiency model seem to be valid for mixed-species flocking. However, in the case of monospecific flocks, the territory maintenance could be the most important factor.

  7. Single versus multiple enemies and the impact on biological control of spider mites in cassava fields in West-Africa

    NARCIS (Netherlands)

    Onzo, A.; Sabelis, M.W.; Hanna, R.

    2014-01-01

    To determine whether to use single or multiple predator species for biological pest control requires manipulative field experiments. We performed such tests in Benin (West Africa) in cassava fields infested by the cassava green mite Mononychellus tanajoa, and the cotton red mite Oligonychus

  8. A remote control system for the LELA experiment

    International Nuclear Information System (INIS)

    Castellano, M.; Cavallo, N.; Cevenini, F.; Patteri, P.

    1983-01-01

    A modular system for closed loop computer control of stepping motors has been realized and used for optical component movement of LELA experiment in radiation risk area. A CAMAC module, controlling up to 15 stepping motors, a NIM dual motor driver and a special purpose circuit for computer interfacing are described

  9. [Risk assessment and control strategies of pests in Lycium barbarum fields under different managements].

    Science.gov (United States)

    Zhao, Zi-Hua; Zhang, Rong; He, Da-Han; Wang, Fang; Zhang, Ting-Ting; Zhang, Zong-Shan

    2009-04-01

    In the risk assessment of pests, both the community structure and the environmental factors should be considered at the same time, because of their mutual effects on the outbreak of disaster pests. This paper established a comprehensive assessment system, including 2 sub-systems, 5 respects, and 14 indices. In the meanwhile, risk assessment indices and experience formula were used to analyze the risk degree of pests in Lycium barbarum fields under different managements. It was found that using risk assessment indices and experience formula could obtain similar results. In abandoned field, Aceria palida, Aphis sp., and Paratrioza sinica were the frequent disaster pests, Lema decempunctata, Neoceratitis asiatica, Jaapiella sp., and Phthorimaea sp. were the incidental disaster pests, and Psylliodes obscurofaciata and Phthorimaea sp. were general pests. In organic field, the frequent disaster pests were the same species as those in abandoned field, while P. indicus, Jaapiella sp. and Phthorimaea sp. were the incidental disaster pests. In chemical control field, A. palida, Aphis sp., P. sinica, and P. indicus were the frequent disaster pests, while Jaapiella sp. and Phthorimaea sp. were the incidental disaster pests. Optimal 5 separations most fitted the division of pest sub-communities in L. barbarum fields, which were infancy period (from March 28 to April 15), outbreak I period (from April 15 to July 18), dormancy period (from July 18 to September 8), outbreak II period (from September 8 to October 15), and recession period (after October 15). The matrix of correlation coefficient showed that the dynamics of pests in L. barbarum fields under different managements were significantly correlated with each other, suggesting that the dynamics of pest populations was similar in different L. barbarum fields, which had two population establishment stages and one exponential growth stage in every year. The optimal controlling stages were from late infancy period to early and

  10. Variability in Small Hive Beetle (Coleoptera: Nitidulidae) Reproduction in Laboratory and Field Experiments.

    Science.gov (United States)

    Meikle, William G; Holst, Niels; Cook, Steven C; Patt, Joseph M

    2015-06-01

    Experiments were conducted to examine how several key factors affect population growth of the small hive beetle, Aethina tumida Murray (Coleoptera: Nitidulidae). Laboratory experiments were conducted to examine effects of food quantity and temperature on reproduction of cohorts of young A. tumida adults (1:1 sex ratio) housed in experimental arenas. Daily numbers and total mass of larvae exiting arenas were highly variable within treatment. Either one or two cohorts of larvae were observed exiting the arenas. Food quantity, either 10 g or 20 g, did not significantly affect the number of larvae exiting arenas at 32°C, but did at 28°C; arenas provided 20 g food produced significantly more larvae than arenas provided 10 g. Temperature did not affect the total mass of larvae provided 10 g food, but did affect larval mass provided 20 g; beetles kept at 28°C produced more larval mass than at 32°C. Field experiments were conducted to examine A. tumida reproductive success in full strength bee colonies. Beetles were introduced into hives as egg-infested frames and as adults, and some bee colonies were artificially weakened through removal of sealed brood. Efforts were unsuccessful; no larvae were observed exiting from, or during the inspection of, any hives. Possible reasons for these results are discussed. The variability observed in A. tumida reproduction even in controlled laboratory conditions and the difficulty in causing beetle infestations in field experiments involving full colonies suggest that accurately forecasting the A. tumida severity in such colonies will be difficult. Published by Oxford University Press on behalf of Entomological Society of America 2015. This work is written by US Government employees and is in the public domain in the US.

  11. Field experiment on 222Rn flux from reclaimed uranium tailings

    International Nuclear Information System (INIS)

    Hinton, T.G.

    1983-01-01

    Design and construction techniques are described for a 1.6 ha experimental uranium mill tailings reclamation plot. A passive, activated charcoal device was developed and tested for measurements of radon flux. Experiments on radon flux versus overburden depth showed that tailings covered with 1.5 m of revegetated or 0.3 m of bare overburden had exhalation rates comparable to background. Vegetated subplots exhibited a significantly higher (often an order of magnitude) flux than the bare subplots. Results on the variation of flux over time did not reveal any definitive patterns, possibly due to the high variability among replicates. A positive correlation was demonstrated between precipitation and radon flux. This is discussed in detail and possibly explained by the increase in water content of the micropores within the tailings, which increases the emanation coefficient without adversely effecting the diffusion coefficient of the overburden. 30 references, 7 figures, 3 tables

  12. Auto-control experiments on DIDO using discontinuous feedback

    International Nuclear Information System (INIS)

    Lawrence, L.A.J.

    1959-12-01

    Experiments on auto-controlling the reactor DIDO are described and the equipment design discussed in some detail. The experiments are carried out to show the suitability of an on/off type of control for the maintenance of: (a) a constant flux level in the presence of noise. (b) constant period during power change. The controlling signals stem from measurement of neutron flux computed to give deviation from demanded power, and period respectively. These signals are fed to a D.C. amplifier with variable deadbang whose output is used to control relays, these in turn control the coarse control arms by means of three-phase motors. The system is designed on the basis of locus diagrams, a conventional non-linear technique being used to handle the relay performance. Calculation of the reactor transfer function at high and low power respectively shows that the stability margin is not appreciably affected by the inherent thermodynamic feedback in the reactor core. (author)

  13. Understanding strong-field coherent control: Measuring single-atom versus collective dynamics

    International Nuclear Information System (INIS)

    Trallero-Herrero, Carlos; Weinacht, Thomas; Spanner, Michael

    2006-01-01

    We compare the results of two strong field coherent control experiments: one which optimizes multi-photon population transfer in atomic sodium (from the 3s to the 4s state, measured by spontaneous emission from the 3p-3s transition) with one that optimizes stimulated emission on the 3p-3s transition in an ensemble of sodium atoms. Both experiments make use of intense, shaped ultrafast laser pulses discovered by a Genetic Algorithm inside a learning control loop. Optimization leads to improvements in the spontaneous and stimulated emission yields of about 4 and 10 4 , respectively, over an unshaped pulse. We interpret these results by modeling both the single atom dynamics as well as the stimulated emission buildup through numerical integration of Schroedinger's and Maxwell's equations. Our interpretation leads to the conclusion that modest yields for controlling single quantum systems can lead to dramatic effects whenever an ensemble of such systems acts collectively following controlled impulsive excitation

  14. Gas box control system for Tandem Mirror Experiment-Upgrade

    International Nuclear Information System (INIS)

    Bell, H.H. Jr.; Hunt, A.L.; Clower, C.A. Jr.

    1983-01-01

    The Tandem Mirror Experiment-Upgrade (TMX-U) uses several methods to feed gas (usually deuterium) at different energies into the plasma region of the machine. One is an arrangement of eight high-speed piezo-electric valves mounted on special manifolds (gas box) that feed cold gas directly to the plasma. This paper describes the electronic valve control and data acquisition portions of the gas box, which are controlled by a desk-top computer. Various flow profiles have been developed and stored in the control computer for ready access by the operator. The system uses two modes of operation, one that exercises and characterizes the valves and one that operates the valves with the rest of the experiment. Both the valve control signals and the pressure transducers data are recorded on the diagnostics computer so that they are available for experiment analysis

  15. Magnetohydrodynamic effects of current profile control in reversed field pinches

    International Nuclear Information System (INIS)

    Sovinec, C.R.; Prager, S.C.

    1999-01-01

    Linear and non-linear MHD computations are used to investigate reversed field pinch configurations with magnetic fluctuations reduced through current profile control. Simulations with reduced ohmic drive and moderate auxiliary current drive, represented generically with an electron force term, applied locally in radius near the plasma edge show magnetic fluctuation energies that are orders of magnitude smaller than those in simulations without profile control. The core of the improved configurations has reduced magnetic shear and closed flux surfaces in some cases, and reversal is sustained through the auxiliary current drive. Modes resonant near the edge may become unstable with auxiliary drive, but their saturation levels can be controlled. The space of auxiliary drive parameters is explored, and the ill effects of deviating far from optimal conditions is demonstrated in non-linear simulations. (author)

  16. Nanomodified heat-accumulating materials controlled by a magnetic field

    Science.gov (United States)

    Shchegolkov, Alexander; Shchegolkov, Alexey; Dyachkova, Tatyana; Bodin, Nikolay; Semenov, Alexander

    2017-11-01

    The paper presents studies of nanomodified heat-accumulating materials controlled by a magnetic field. In order to obtain controlled heat-accumulating materials, synthetic motor oil CASTROL 0W30, ferromagnetic particles, CNTs and paraffin were used. Mechanically activated carbon nanotubes with ferromagnetic particles were used for the nanomodification of paraffin. Mechanoactivation ensured the production of ferromagnetic particles with an average particle size of 5 µm. Using an extrusion plant, a mixture of CNTs and ferromagnetic particles was introduced into the paraffin. Further, the nanomodified paraffin in a granular form was introduced into synthetic oil. To conduct experimental studies, a contactless method for measuring temperature was used. The thermal contact control with the help of the obtained nanomodified material is possible with a magnetic induction of 1250 mT, and a heat flux of about 74 kW/m2 is provided at the same time.

  17. Worm Control in Livestock: Bringing Science to the Field.

    Science.gov (United States)

    Kenyon, Fiona; Hutchings, Fiona; Morgan-Davies, Claire; van Dijk, Jan; Bartley, Dave J

    2017-09-01

    Parasitic roundworm infections are ubiquitous in grazing livestock. Chemical control through the frequent 'blanket' administration of anthelmintics (wormers) has been, and remains, the cornerstone in controlling these infections, but this practice is unsustainable. Alternative strategies are available but, even with the plethora of best practice advice available, have yet to be integrated into routine farming practice. This is probably due to a range of factors, including contradictory advice from different sources, changes to advice following increased scientific understanding, and top-down knowledge exchange patterns. In this article, we discuss the worm control options available, the translation of new best practice advice from science bench to field, and ideas for future work and directions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. The lure of local SETI: Fifty years of field experiments

    Science.gov (United States)

    Ailleris, Philippe

    2011-01-01

    With the commemoration in October 2007 of the Sputnik launch, space exploration celebrated its 50th anniversary. Despite impressive technological and scientific achievements the fascination for space has weakened during the last decades. One contributing factor has been the gradual disappearance of mankind's hope of discovering extraterrestrial life within its close neighbourhood. In striking contrast and since the middle of the 20th century, a non-negligible proportion of the population have already concluded that intelligent beings from other worlds do exist and visit Earth through space vehicles popularly called Unidentified Flying Objects (UFOs). In light of the continuous public interest for the UFO enigma symbolized by the recent widely diffused media announcements on the release of French and English governmental files; and considering the approach of broadening the strategies of the "Active SETI" approach and the existence of a rich multi-disciplinary UFO documentation of potential interest for SETI; this paper describes some past scientific attempts to demonstrate the physical reality of the phenomena and potentially the presence on Earth of probes of extraterrestrial origin. Details of the different instrumented field studies deployed by scientists and organizations during the period 1950-1990 in the USA, Canada and Europe are provided. In conclusion it will be argued that while continuing the current radio/optical SETI searches, there is the necessity to maintain sustaining attention to the topic of anomalous aerospace phenomena and to develop new rigorous research approaches.

  19. Design of a new large s field reversed configuration experiment

    International Nuclear Information System (INIS)

    Hoffman, A.L.; Slough, J.T.

    1986-01-01

    The present TRX facility utilizes programmed formation techniques to form s = 2 plasmas in a 20 cm diameter by 1 m long plasma tube. LSX will have an 80 cm diameter by 4 m long plasma tube and will employ the same programmed formation techniques as TRX. This should result in s = 8 plasmas and FRC flux and energy lifetimes in the msec range if the presently measured scaling persists. LSX will be initially restricted to an external field of 7.5 kG, and typical plasma conditions will be 300 eV electron and ion temperatures and electron or ion densities of about 2x10/sup 15/ cm/sup -3/. The low voltage formation techniques developed in TRX-2 (Eθ /sub values of about 100 volts/cm) will also be employed on LSX, so that relatively low voltage power supplies can be utilized. A modified form of second half cycle circuitry is planned to replace the function of a large reverse bias capacitor bank. The increase in total power supply efficiency allows the primary magnet energy storage to be less that 1 MJ

  20. Escompte Field Experiment : Some Preliminary Results About The Iop 2

    Science.gov (United States)

    Cros, B.; Durand, P.; Ancellet, G.; Calpini, B.; Frejafon, E.; Jambert, C.; Serça, D.; Sol, B.; Wortham, H.; Zephoris, M.

    One of the main goals of the ESCOMPTE programme is to create an appropriate -3D data base including emissions, transport and air composition measurements during urban pollution episodes. ESCOMPTE will as well as provide a highly documented framework for dynamical and chemical studies. For this purpose a field campaign was carried out in Marseille -Berre area in the south-eastern of France from June 4 to July 13, 2001. Five pollution events (IOP) were documented. The second one called IOP2 is particularly interesting in term of photochemical pollution. The chemical evolution of the urban and industrial plumes and the orographic influence are analysed from surface, remote sensing and airborne measurements. This IOP 2 of six days duration ( June 21 to June 26) will be presented . It began with a moderate S/SW wind (an end of Mistral situation) , clear skies and hot temperature (>30rC). Marseille and Berre plumes extended towards the East and over the sea. The highest surface ozone concentration were found around Toulon area. This first period (23-26/06) so called IOP 2a was followed by IOP 2b, three days of very hot temperature (>34rC) and high surface concentration in ozone - 100 ppbv over the whole domain , 125 ppbv all around Aix on the 24 up to 150 ppbv in the durance valley on the 25.

  1. Advanced Rooftop Control (ARC) Retrofit: Field-Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Weimin; Katipamula, Srinivas; Ngo, Hung; Underhill, Ronald M.; Taasevigen, Danny J.; Lutes, Robert G.

    2013-07-31

    The multi-year research study was initiated to find solutions to improve packaged equipment operating efficiency in the field. Pacific Northwest National Laboratory (PNNL), with funding from the U.S. Department of Energy’s (DOE’s) Building Technologies Office (BTO) and Bonneville Power Administration (BPA) conducted this research, development and demonstration (RD&D) study. Packaged equipment with constant speed supply fans is designed to provide ventilation at the design rate at all times when the fan is operating as required by building code. Although there are a number of hours during the day when a building may not be fully occupied or the need for ventilation is lower than designed, the ventilation rate cannot be adjusted easily with a constant speed fan. Therefore, modulating the supply fan in conjunction with demand controlled ventilation (DCV) will not only reduce the coil energy but also reduce the fan energy. The objective of this multi-year research, development and demonstration project was to determine the magnitude of energy savings achievable by retrofitting existing packaged rooftop air conditioners with advanced control strategies not ordinarily used for packaged units. First, through detailed simulation analysis, it was shown that significant energy (between 24% and 35%) and cost savings (38%) from fan, cooling and heating energy consumption could be realized when packaged air conditioning units with gas furnaces are retrofitted with advanced control packages (combining multi-speed fan control, integrated economizer controls and DCV). The simulation analysis also showed significant savings for heat pumps (between 20% and 60%). The simulation analysis was followed by an extensive field test of a retrofittable advanced rooftop unit (RTU) controller.

  2. Proposal for the ZT-40 reversed-field Z-pinch experiment

    International Nuclear Information System (INIS)

    Baker, D.A.; Machalek, M.D.

    1977-08-01

    A next-generation, toroidal, reversed-field Z-pinch experiment to be constructed at LASL is proposed. On the basis of encouraging ZT-I and ZT-S experimental results, a larger device with a 40-cm bore and a 114-cm major radius is proposed, to extend the confinement time by about an order of magnitude. The new experiment will explore the physics of programming reversed-field pinches in a size range unexplored by previous reversed-field pinch experiments. Model reversed-field pinch reactor calculations show that, if stability is assumed, small fusion reactors are possible if the pinch current density is high. A basic aim will be to delineate the plasma and current density ranges in which stable reversed-field pinches can be produced. Improved vacuum techniques will be used to overcome the radiation losses that probably kept electron temperatures low in the earlier, smaller experiments

  3. Experiments and Modeling to Support Field Test Design

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Peter Jacob [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bourret, Suzanne Michelle [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Zyvoloski, George Anthony [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Boukhalfa, Hakim [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Stauffer, Philip H. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Weaver, Douglas James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-09-25

    Disposition of heat-generating nuclear waste (HGNW) remains a continuing technical and sociopolitical challenge. We define HGNW as the combination of both heat generating defense high level waste (DHLW) and civilian spent nuclear fuel (SNF). Numerous concepts for HGNW management have been proposed and examined internationally, including an extensive focus on geologic disposal (c.f. Brunnengräber et al., 2013). One type of proposed geologic material is salt, so chosen because of its viscoplastic deformation that causes self-repair of damage or deformation induced in the salt by waste emplacement activities (Hansen and Leigh, 2011). Salt as a repository material has been tested at several sites around the world, notably the Morsleben facility in Germany (c.f. Fahland and Heusermann, 2013; Wollrath et al., 2014; Fahland et al., 2015) and at the Waste Isolation Pilot Plant (WIPP) near Carlsbad, NM. Evaluating the technical feasibility of a HGNW repository in salt is an ongoing process involving experiments and numerical modeling of many processes at many facilities.

  4. Translation experiment of a plasma with field reversed configuration

    International Nuclear Information System (INIS)

    Tanjyo, Masayasu; Okada, Shigefumi; Ito, Yoshifumi; Kako, Masashi; Ohi, Shoichi

    1984-01-01

    Experiments to translate the FRC plasma from is formation area (pinch coil) into two kinds of metal vessels (magnetic flux conservers) with larger and smaller bore than that of the pinch coil have been carried out in OCT with an aim of improving the particle confinement time tau sub(N) by increasing xsub(s) (ratio of the plasma radius to that of the conducting wall). Demonstrated were successful translations of the plasma into both vessels. The xsub(s) of the translated plasma increased to 0.6 in the larger bore vessel and to 0.7 in the smaller one from 0.4 of the source plasma in the pinch coil. With the increase in xsub(s), tau sub(N) and also decay time of the trapped magnetic flux are extended from 15 - 20 μs of the source plasma to 50 - 80 μs. The tau sub(N) is found to have stronger dependence on xsub(s) than on rsub(s). During the translation phase, almost half of the total particle and the plasma energy are lost. The plasma volume is, therefore, about half of that expected from the analysis on the ideal translation process. It is also found that the translation process is nearly isothermal as is expected from the analysis. (author)

  5. High gain requirements and high field Tokamak experiments

    International Nuclear Information System (INIS)

    Cohn, D.R.

    1994-01-01

    Operation at sufficiently high gain (ratio of fusion power to external heating power) is a fundamental requirement for tokamak power reactors. For typical reactor concepts, the gain is greater than 25. Self-heating from alpha particles in deuterium-tritium plasmas can greatly reduce ητ/temperature requirements for high gain. A range of high gain operating conditions is possible with different values of alpha-particle efficiency (fraction of alpha-particle power that actually heats the plasma) and with different ratios of self heating to external heating. At one extreme, there is ignited operation, where all of the required plasma heating is provided by alpha particles and the alpha-particle efficiency is 100%. At the other extreme, there is the case of no heating contribution from alpha particles. ητ/temperature requirements for high gain are determined as a function of alpha-particle heating efficiency. Possibilities for high gain experiments in deuterium-tritium, deuterium, and hydrogen plasmas are discussed

  6. The Escompte Programme: An Overview of The Field Experiment

    Science.gov (United States)

    Durand, P.; Cros, B.; Peuch, V. H.; Kottmeier, C.; Saïd, F.; Perros, P.; Robin, D.

    The ESCOMPTE programme (http://medias.obs-mip.fr/escompte) is embedded in a long-term strategy whose aim is the improvement of air quality. In order to be able to take preventive measures to reduce the size and the effects of pollution events, we need to dispose of efficient tools of prediction of these events. Such tools, yet to be developed or improved, are, on the one hand, the inventory of the various pollu- tion sources (fixed and mobile), and, on the other hand, mathematical models able to accurately simulate the dynamical (diffusion and transport) and chemical (reactions) processes under which the various solid, liquid and gaseous species will evolve. The main objective of the ESCOMPTE programme is to gather a data set of some pollution events, involving the emissions of primary pollutants, as well as atmospheric dynam- ics and chemistry. This data set, acquired at the surface and in the lower troposphere, in a region located South-East of France, between June 4th and July 16th, 2001, will serve as a reference for qualifying the CTMs of atmospheric pollution, from local- to regional-scale. A 120km*120km area, around the "Marseille-Berre" site, in the South-eastern of France, has been selected to host the ESCOMPTE field campaign. This region presents a high occurrence of photochemical pollution, because it is one of the most sunny re- gions of France, with anticyclonic conditions prevailing during summer ; it involves the urbanized area of Marseille city (more than one million people), and the "Fos- Berre" industrial area (oil refineries, power plants, E), both being considerable sources of various pollutants ; it presents terrain characteristics (land-sea-breeze circulations ; numerous hills and mountain chains up to more than thousand meters high) acting as dynamical forcings on the transport of pollutants. Although the core domain of ESCOMPTE is a 100km*100km box, a hierarchy of chemistry and/or transport models is involved in the programme, and is able do

  7. Field-effect Flow Control in Polymer Microchannel Networks

    Science.gov (United States)

    Sniadecki, Nathan; Lee, Cheng S.; Beamesderfer, Mike; DeVoe, Don L.

    2003-01-01

    A new Bio-MEMS electroosmotic flow (EOF) modulator for plastic microchannel networks has been developed. The EOF modulator uses field-effect flow control (FEFC) to adjust the zeta potential at the Parylene C microchannel wall. By setting a differential EOF pumping rate in two of the three microchannels at a T-intersection with EOF modulators, the induced pressure at the intersection generated pumping in the third, field-free microchannel. The EOF modulators are able to change the magnitude and direction of the pressure pumping by inducing either a negative or positive pressure at the intersection. The flow velocity is tracked by neutralized fluorescent microbeads in the microchannels. The proof-of-concept of the EOF modulator described here may be applied to complex plastic ,microchannel networks where individual microchannel flow rates are addressable by localized induced-pressure pumping.

  8. Tools and setups for experiments with AC and rotating magnetic fields

    International Nuclear Information System (INIS)

    Ponikvar, D

    2010-01-01

    A rotating magnetic field is the basis for the transformation of electrical energy to mechanical energy. School experiments on the rotating magnetic field are rare since they require the use of specially prepared mechanical setups and/or relatively large, three-phase power supplies to achieve strong magnetic fields. This paper proposes several experiments and describes setups and tools which are easy to obtain and work with. Free software is offered to generate the required signals by a personal computer. The experiments can be implemented in introductory physics courses on electromagnetism for undergraduates or specialized courses at high schools.

  9. Advanced feedback control methods in EXTRAP T2R reversed field pinch

    Science.gov (United States)

    Yadikin, D.; Brunsell, P. R.; Paccagnella, R.

    2006-07-01

    Previous experiments in the EXTRAP T2R reversed field pinch device have shown the possibility of suppression of multiple resistive wall modes (RWM). A feedback system has been installed in EXTRAP T2R having 100% coverage of the toroidal surface by the active coil array. Predictions based on theory and the previous experimental results show that the number of active coils should be sufficient for independent stabilization of all unstable RWMs in the EXTRAP T2R. Experiments using different feedback schemes are performed, comparing the intelligent shell, the fake rotating shell, and the mode control with complex feedback gains. Stabilization of all unstable RWMs throughout the discharge duration of td≈10τw is seen using the intelligent shell feedback scheme. Mode rotation and the control of selected Fourier harmonics is obtained simultaneously using the mode control scheme with complex gains. Different sensor signals are studied. A feedback system with toroidal magnetic field sensors could have an advantage of lower feedback gain needed for the RWM suppression compared to the system with radial magnetic field sensors. In this study, RWM suppression is demonstrated, using also the toroidal field component as a sensor signal in the feedback system.

  10. Advanced feedback control methods in EXTRAP T2R reversed field pinch

    International Nuclear Information System (INIS)

    Yadikin, D.; Brunsell, P. R.; Paccagnella, R.

    2006-01-01

    Previous experiments in the EXTRAP T2R reversed field pinch device have shown the possibility of suppression of multiple resistive wall modes (RWM). A feedback system has been installed in EXTRAP T2R having 100% coverage of the toroidal surface by the active coil array. Predictions based on theory and the previous experimental results show that the number of active coils should be sufficient for independent stabilization of all unstable RWMs in the EXTRAP T2R. Experiments using different feedback schemes are performed, comparing the intelligent shell, the fake rotating shell, and the mode control with complex feedback gains. Stabilization of all unstable RWMs throughout the discharge duration of t d ≅10τ w is seen using the intelligent shell feedback scheme. Mode rotation and the control of selected Fourier harmonics is obtained simultaneously using the mode control scheme with complex gains. Different sensor signals are studied. A feedback system with toroidal magnetic field sensors could have an advantage of lower feedback gain needed for the RWM suppression compared to the system with radial magnetic field sensors. In this study, RWM suppression is demonstrated, using also the toroidal field component as a sensor signal in the feedback system

  11. Study on the weediness of winter wheat in a long-term fertilization field experiment.

    Science.gov (United States)

    Lehoczky, E; Kismányoky, A; Kismányoky, T

    2006-01-01

    The study was carried out in Keszthely, in the long-term fertilization field experiment in April of 2005. In the experiment we had opportunity to compare the weediness in NPK and NPK + FYM* treatments, and we could study the effect of increasing N dosis on the weeds and winter wheat. The weed survey was made on the 20th of April at the end of tillering. For the weed survey used the Balázs-Ujvárosi method. After that we collected all the weeds from the plots per 1 m2. We counted, measured the fresh and dry matter weight of aerial parts. Winter wheat sampels were taken also from all plots (1 running meter per plot). In the experiment 10 weed species were found, 9 annual: Ambrosia artemisiifolia, Consolida regalis, Galium aparine, Lamiunt amplexicaule, Matricaria inodora, Papaver rhoeas, Stellaria media, Veronica hederifolia, Veronica triphyllos, and 1 perennial: Cirsium arvense. Veronica hederifolia was the dominant species in both fertilized plots, Stellaria media has the second highest weed coverage. The manuring treatments, and the N-dosis has important and significantly effect to the weedeness and the biomass production of winter wheat. On the control plots was the relation of biomass weight of weeds the highest. This relation reduced to the effect of N treatments, wich had an favorable effect on the winter wheat.

  12. Nomad rover field experiment, Atacama Desert, Chile 1. Science results overview

    Science.gov (United States)

    Cabrol, N. A.; Thomas, G.; Witzke, B.

    2001-04-01

    Nomad was deployed for a 45 day traverse in the Atacama Desert, Chile, during the summer of 1997. During this traverse, 1 week was devoted to science experiments. The goal of the science experiments was to test different planetary surface exploration strategies that included (1) a Mars mission simulation, (2) a science on the fly experiment, where the rover was kept moving 75% of the operation time. (The goal of this operation was to determine whether or not successful interpretation of the environment is related to the time spent on a target. The role of mobility in helping the interpretation was also assessed.) (3) a meteorite search using visual and instrumental methods to remotely identify meteorites in extreme environments, and (4) a time-delay experiment with and without using the panospheric camera. The results were as follow: the remote science team positively identified the main characteristics of the test site geological environment. The science on the fly experiment showed that the selection of appropriate targets might be even more critical than the time spent on a study area to reconstruct the history of a site. During the same operation the science team members identified and sampled a rock from a Jurassic outcrop that they proposed to be a fossil. The presence of paleolife indicators in this rock was confirmed later by laboratory analysis. Both visual and instrumental modes demonstrated the feasibility, in at least some conditions, of carrying out a field search for meteorites by using remote-controlled vehicles. Finally, metrics collected from the observation of the science team operations, and the use team members made of mission data, provided critical information on what operation sequences could be automated on board rovers in future planetary surface explorations.

  13. On transient electric fields observed in chemical release experiments by rockets

    International Nuclear Information System (INIS)

    Marklund, G.; Brenning, N.; Holmgren, G.; Haerendel, G.

    1986-06-01

    As a follow-up to the successful chemical release experiment Trigger in 1977, the TOR (Trigger Optimized Repetition) rocket was launched from Esrange on Oct. 24, 1984. Like in the Trigger experiment a large amplitude electric field pulse of 200 mV/m was detected shortly after the explosion. The central part of the pulse was found to be clearly correlated with an intense layer of swept up ambient particles behind a propagating shock-front. The field was directed towards the centre of the expanding ionized cloud, which is indicative of a polarisation electric field source. Expressions for this radial polarisation field and the much weaker azimuthal induced electric field are derived from a simple cylindrical model for the field and the expanding neutral cloud. Time profiles of the radial electric field are shown to be in good agreement with observations. (authors)

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

    Science.gov (United States)

    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…

  15. The detector control system of the ATLAS experiment

    International Nuclear Information System (INIS)

    Poy, A Barriuso; Burckhart, H J; Cook, J; Franz, S; Gutzwiller, O; Hallgren, B; Schlenker, S; Varela, F; Boterenbrood, H; Filimonov, V; Khomutnikov, V

    2008-01-01

    The ATLAS experiment is one of the experiments at the Large Hadron Collider, constructed to study elementary particle interactions in collisions of high-energy proton beams. The individual detector components as well as the common experimental infrastructure are supervised by the Detector Control System (DCS). The DCS enables equipment supervision using operator commands, reads, processes and archives the operational parameters of the detector, allows for error recognition and handling, manages the communication with external control systems, and provides a synchronization mechanism with the physics data acquisition system. Given the enormous size and complexity of ATLAS, special emphasis was put on the use of standardized hardware and software components enabling efficient development and long-term maintainability of the DCS over the lifetime of the experiment. Currently, the DCS is being used successfully during the experiment commissioning phase

  16. Live controls for radioisotope tracer food chain experiments using meiofauna

    International Nuclear Information System (INIS)

    Montagna, P.A.

    1983-01-01

    Formalin poisoned samples are inadequate for measuring the amount of label to be subtracted as control values for certain food chain studies that employ radioactive tracers. In some studies, tracer is added just before incubation to label ''food'' during the feeding study. Commonly, parallel, poisoned incubations are used to distinguish between biotic and abiotic label incorporation. But, a poisoned control does not account for label that could enter a consumer via active transport, epicuticular microfloral uptake, or grazing on labeled, non-food particles. Experiments were performed to test if label uptake is greater in live non-grazing than dead organisms. Marine benthic meiofauna incoporate from 3 to 133 times more tracer when they are alive and not grazing than when they are formalin killed. These results suggest that control experiments with live animals be performed to measure all processes by which label can enter consumers in food chain experiments. (orig.)

  17. Experience of digital control systems in Scandinavian BWRs

    International Nuclear Information System (INIS)

    Rydahl, I.

    1989-01-01

    Since 1984 digital control systems have been in operation in various Scandinavian BWRs. Examples of such digital control systems are: dual microprocessor based system for complete control of radwaste plant, three channel recirculation control system, and three channel feedwater control system. This paper describes Swedish development from one channel through three channel analog control systems to digital systems. The author describes experience of digital control systems during design, testing, commissioning and operation. The main benefits of digital compared with analog technology are discussed. Especially the outstanding facility of using a built-in process simulator for commissioning and tuning. The use of digital technology in nuclear safety system and future plans are dealt with

  18. The Passy-2015 field experiment: wintertime atmospheric dynamics and air quality in a narrow alpine valley

    Science.gov (United States)

    Paci, Alexandre; Staquet, Chantal

    2016-04-01

    Wintertime anticyclonic conditions lead to the formation of persistent stable boundary layers which may induce severe air pollution episodes in urban or industrialized area, particularly in mountain regions. The Arve river valley in the Northern Alps is very sensitive to this phenomenon, in particular close to the city of Passy (Haute-Savoie), 20 km down valley past Chamonix. This place is indeed one of the worst place in France regarding air quality, the concentration of fine particles and Benzo(a)pyrene (a carcinogenic organic compound) regularly exceeding the EU legal admissible level during winter. Besides air quality measurements, such as the ones presently carried in the area by the local air quality agency Air Rhône-Alpes or in the DECOMBIO project led by LGGE, it is crucial to improve our knowledge of the atmospheric boundary layer dynamics and processes at the valley scale under these persistent stable conditions in order to improve our understanding on how it drives pollutant dispersion. These issues motivated the Passy-2015 field experiment which took place during the winter 2014-2015. A relatively large set-up of instruments was deployed on a main measurement site in the valley center and on four other satellite sites. It includes several remote sensing instruments, a surface flux station, a 10 m instrumented tower, a large aperture scintillometer, a fog monitoring station among others. Most of the instruments were present from early January to the end of February. During two intensive observation periods, 6-14 February and 17-20 February, the instrumental set-up was completed on the main site with high frequency radio-soundings (up to one per 1h30), a tethered balloon, a remote controlled drone quadcopter and a sodar. The field campaign, the instruments, the meteorological situations observed and preliminary results will be presented. This field experiment is part of the Passy project funded by ADEME through the French national programme LEFE/INSU and

  19. Experiments in power distribution control on the IRT-2000 reactor

    International Nuclear Information System (INIS)

    Filipchuk, E.V.; Potapenko, P.T.; Trofimov, A.P.; Kosilov, A.N.; Neboyan, V.T.; Timokhin, E.S.

    1975-01-01

    The results from the experimental investigations of a system for regulating the neutron field on a research reactor IRT-2000 are shown. The right of such experiments on a reactor with a little active zone is substantiated. A successful attempt was made in this work to apply primary elements of straight charging in the neutron field regulating system. A system with independent instrumentally local regulators, a system with hard cross connections and a structure with a ''floating'' installation are studied. Serial common industrial regulators BRT-2 were used

  20. Graphene levitation and orientation control using a magnetic field

    Science.gov (United States)

    Niu, Chao; Lin, Feng; Wang, Zhiming M.; Bao, Jiming; Hu, Jonathan

    2018-01-01

    This paper studies graphene levitation and orientation control using a magnetic field. The torques in all three spatial directions induced by diamagnetic forces are used to predict stable conditions for different shapes of millimeter-sized graphite plates. We find that graphite plates, in regular polygon shapes with an even number of sides, will be levitated in a stable manner above four interleaved permanent magnets. In addition, the orientation of micrometer-sized graphene flakes near a permanent magnet is studied in both air and liquid environments. Using these analyses, we are able to simulate optical transmission and reflection on a writing board and thereby reveal potential applications using this technology for display screens. Understanding the control of graphene flake orientation will lead to the discovery of future applications using graphene flakes.

  1. Rapid Software Development for Experiment Control at OPAL

    International Nuclear Information System (INIS)

    Hathaway, P.V.; Lam, Tony; Franceschini, Ferdi; Hauser, Nick; Rayner, Hugh

    2005-01-01

    Full text: ANSTO is undertaking the parallel development of instrument control and graphical experiment interface software for seven neutron beam instruments at OPAL. Each instrument poses several challenges for a common system solution, including custom detector interfaces, a range of motion and beamline optics schema, and a spectrum of online data reduction requirements. To provide a superior system with the least development effort, the computing team have adopted proven, configurable, server-based control software (SICS)1., a highly Integrated Scientific Experimental Environment (GumTree)2. and industry-standard database management systems. The resulting graphical interfaces allow operation in a familiar experiment domain, with monitoring of data and parameters independent of control system specifics. GumTree presents the experimenter with a consistent interface for experiment management, instrument control and data reduction tasks. The facility instrument scientists can easily reconfigure instruments and add ancillaries. The user community can expect a reduced learning curve for performing each experiment. GumTree can be installed anywhere for pre-experiment familiarisation, postprocessing of acquired data sets, and integration with third party analysis tools. Instrument scientists are seeing faster software development iterations and have a solid basis to prepare for the next suite of instruments. 1. SICS from PSI (lns00.psi.ch). 2. GumTree (gumtree.sourceforge.net), new site: http://gumtree.sourceforge.net/wiki/index.php/Main_Page

  2. Qudi: A modular python suite for experiment control and data processing

    Directory of Open Access Journals (Sweden)

    Jan M. Binder

    2017-01-01

    Full Text Available Qudi is a general, modular, multi-operating system suite written in Python 3 for controlling laboratory experiments. It provides a structured environment by separating functionality into hardware abstraction, experiment logic and user interface layers. The core feature set comprises a graphical user interface, live data visualization, distributed execution over networks, rapid prototyping via Jupyter notebooks, configuration management, and data recording. Currently, the included modules are focused on confocal microscopy, quantum optics and quantum information experiments, but an expansion into other fields is possible and encouraged.

  3. Thermal control surfaces on the MSFC LDEF experiments

    International Nuclear Information System (INIS)

    Wilkes, D.R.; Whitaker, A.F.; Zwiener, J.M.; Linton, R.C.; Shular, D.; Peters, P.N.; Gregory, J.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

  4. Success-Breeds-Success in Collective Political Behavior: Evidence from a Field Experiment

    NARCIS (Netherlands)

    Van De Rijt, Arnout; Akin, Idil; Willer, Robb; Feinberg, Matthew

    2016-01-01

    Scholars have proposed that the emergence of political movements is highly pathdependent, such that early mobilization successes may lead to disproportionately greater eventual success. This article replicates a unique field experiment testing for positive feedback in internet petition signing (van

  5. Stress field control during large caldera-forming eruptions

    Directory of Open Access Journals (Sweden)

    Antonio Costa

    2016-10-01

    Full Text Available Crustal stress field can have a significant influence on the way magma is channelled through the crust and erupted explosively at the surface. Large Caldera Forming Eruptions (LCFEs can erupt hundreds to thousands of cubic kilometres of magma in a relatively short time along fissures under the control of a far-field extensional stress. The associated eruption intensities are estimated in the range 109 - 1011 kg/s. We analyse syn-eruptive dynamics of LCFEs, by simulating numerically explosive flow of magma through a shallow dyke conduit connected to a magma chamber that in turn is fed by a deeper magma reservoir, both under the action of an extensional far-field stress. Results indicate that huge amounts of high viscosity silicic magma can be erupted over timescales of a few to several hours. Our study provides answers to outstanding questions relating to the intensity and duration of catastrophic volcanic eruptions in the past. In addition, it presents far-reaching implications for the understanding of dynamics and intensity of large-magnitude volcanic eruptions on Earth and to highlight the necessity of a future research to advance our knowledge of these rare catastrophic events.

  6. Sample cell for in-field X-ray diffraction experiments

    Directory of Open Access Journals (Sweden)

    Viktor Höglin

    2015-01-01

    Full Text Available A sample cell making it possible to perform synchrotron radiation X-ray powder diffraction experiments in a magnetic field of 0.35 T has been constructed. The device is an add-on to an existing sample cell and contains a strong permanent magnet of NdFeB-type. Experiments have shown that the setup is working satisfactory making it possible to perform in-field measurements.

  7. Deep Borehole Field Test Requirements and Controlled Assumptions.

    Energy Technology Data Exchange (ETDEWEB)

    Hardin, Ernest [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-07-01

    This document presents design requirements and controlled assumptions intended for use in the engineering development and testing of: 1) prototype packages for radioactive waste disposal in deep boreholes; 2) a waste package surface handling system; and 3) a subsurface system for emplacing and retrieving packages in deep boreholes. Engineering development and testing is being performed as part of the Deep Borehole Field Test (DBFT; SNL 2014a). This document presents parallel sets of requirements for a waste disposal system and for the DBFT, showing the close relationship. In addition to design, it will also inform planning for drilling, construction, and scientific characterization activities for the DBFT. The information presented here follows typical preparations for engineering design. It includes functional and operating requirements for handling and emplacement/retrieval equipment, waste package design and emplacement requirements, borehole construction requirements, sealing requirements, and performance criteria. Assumptions are included where they could impact engineering design. Design solutions are avoided in the requirements discussion. Deep Borehole Field Test Requirements and Controlled Assumptions July 21, 2015 iv ACKNOWLEDGEMENTS This set of requirements and assumptions has benefited greatly from reviews by Gordon Appel, Geoff Freeze, Kris Kuhlman, Bob MacKinnon, Steve Pye, David Sassani, Dave Sevougian, and Jiann Su.

  8. Active Noise Control Experiments using Sound Energy Flu

    Science.gov (United States)

    Krause, Uli

    2015-03-01

    This paper reports on the latest results concerning the active noise control approach using net flow of acoustic energy. The test set-up consists of two loudspeakers simulating the engine noise and two smaller loudspeakers which belong to the active noise system. The system is completed by two acceleration sensors and one microphone per loudspeaker. The microphones are located in the near sound field of the loudspeakers. The control algorithm including the update equation of the feed-forward controller is introduced. Numerical simulations are performed with a comparison to a state of the art method minimising the radiated sound power. The proposed approach is experimentally validated.

  9. Slow control systems of the Reactor Experiment for Neutrino Oscillation

    International Nuclear Information System (INIS)

    Choi, J.H.; Jang, H.I.; Choi, W.Q.; Choi, Y.; Jang, J.S.; Jeon, E.J.; Joo, K.K.; Kim, B.R.; Kim, H.S.; Kim, J.Y.; Kim, S.B.; Kim, S.Y.; Kim, W.; Kim, Y.D.; Ko, Y.J.; Lee, J.K.; Lim, I.T.; Pac, M.Y.; Park, I.G.; Park, J.S.

    2016-01-01

    The RENO experiment has been in operation since August 2011 to measure reactor antineutrino disappearance using identical near and far detectors. For accurate measurements of neutrino mixing parameters and efficient data taking, it is crucial to monitor and control the detector in real time. Environmental conditions also need to be monitored for stable operation of detectors as well as for safety reasons. In this paper, we report the design, hardware, operation, and performance of the slow control system.

  10. Scenario design : adaptive architecture for command and control experiment eight

    OpenAIRE

    Clark, Frankie J.

    2002-01-01

    Approved for public release; distribution is unlimited. The Adaptive Architectures for Command and Control (A2C2) project is an ongoing research effort sponsored by the Office of Naval Research to explore adaptation in joint command and control. The objective of the project's eighth experiment is to study the adjustments that organizations make when they are confronted with a scenario for which their organizational is ill-suited. To accomplish this, teams will each be in one of two fundame...

  11. Neutral beam control systems for the Tandem Mirror Experiment

    International Nuclear Information System (INIS)

    Ross, R.I.

    1979-01-01

    The Tandem Mirror Experiment (TMX) is presently developing the technology and approaches which will be used in larger fusion systems. This paper describes some of the designs which were used in creating the control system for the TMX neutral beams. To create a system of controls that would work near these large, rapid switching current sources required a mixture of different technologies: fiberoptic data transmission, printed circuit and wirewrap techniques, etc

  12. Multilink manipulator computer control: experience in development and commissioning

    International Nuclear Information System (INIS)

    Holt, J.E.

    1988-11-01

    This report describes development which has been carried out on the multilink manipulator computer control system. The system allows the manipulator to be driven using only two joysticks. The leading link is controlled and the other links follow its path into the reactor, thus avoiding any potential obstacles. The system has been fully commissioned and used with the Sizewell ''A'' reactor 2 Multilink T.V. manipulator. Experience of the use of the system is presented, together with recommendations for future improvements. (author)

  13. Sensed presence and mystical experiences are predicted by suggestibility, not by the application of transcranial weak complex magnetic fields.

    Science.gov (United States)

    Granqvist, Pehr; Fredrikson, Mats; Unge, Patrik; Hagenfeldt, Andrea; Valind, Sven; Larhammar, Dan; Larsson, Marcus

    2005-04-29

    Transcranial magnetic stimulation (TMS) with weak (micro Tesla) complex waveform fields have been claimed to evoke the sensed presence of a sentient being in up to 80% in the general population. These findings have had a questionable neurophysiological foundation as the fields are approximately six orders of magnitude weaker than ordinary TMS fields. Also, no independent replication has been reported. To replicate and extend previous findings, we performed a double-blind experiment (N=89), with a sham-field control group. Personality characteristics indicating suggestibility (absorption, signs of abnormal temporal lobe activity, and a "new age"-lifestyle orientation) were used as predictors. Sensed presence, mystical, and other somatosensory experiences previously reported from the magnetic field stimulation were outcome measures. We found no evidence for any effects of the magnetic fields, neither in the entire group, nor in individuals high in suggestibility. Because the personality characteristics significantly predicted outcomes, suggestibility may account for previously reported effects. Our results strongly question the earlier claims of experiential effects of weak magnetic fields.

  14. Latitudinal and altitudinal controls of Titan's dune field morphometry

    Science.gov (United States)

    Le Gall, A.; Hayes, A. G.; Ewing, R.; Janssen, M. A.; Radebaugh, J.; Savage, C.; Encrenaz, P.; the Cassini Radar Team

    2012-01-01

    Dune fields dominate ˜13% of Titan's surface and represent an important sink of carbon in the methane cycle. Herein, we discuss correlations in dune morphometry with altitude and latitude. These correlations, which have important implications in terms of geological processes and climate on Titan, are investigated through the microwave electromagnetic signatures of dune fields using Cassini radar and radiometry observations. The backscatter and emissivity from Titan's dune terrains are primarily controlled by the amount of interdune area within the radar footprint and are also expected to vary with the degree of the interdunal sand cover. Using SAR-derived topography, we find that Titan's main dune fields (Shangri-La, Fensal, Belet and Aztlan) tend to occupy the lowest elevation areas in Equatorial regions occurring at mean elevations between ˜-400 and ˜0 m (relative to the geoid). In elevated dune terrains, we show a definite trend towards a smaller dune to interdune ratio and possibly a thinner sand cover in the interdune areas. A similar correlation is observed with latitude, suggesting that the quantity of windblown sand in the dune fields tends to decrease as one moves farther north. The altitudinal trend among Titan's sand seas is consistent with the idea that sediment source zones most probably occur in lowlands, which would reduce the sand supply toward elevated regions. The latitudinal preference could result from a gradual increase in dampness with latitude due to the asymmetric seasonal forcing associated with Titan's current orbital configuration unless it is indicative of a latitudinal preference in the sand source distribution or wind transport capacity.

  15. Resistive Wall Mode Stability and Control in the Reversed Field Pinch

    International Nuclear Information System (INIS)

    Yadikin, Dmitriy

    2006-03-01

    Control of MHD instabilities using a conducting wall together with external magnetic fields is an important route to improved performance and reliability in fusion devices. Active control of MHD modes is of interest for both the Advanced Tokamak and the Reversed Field Pinch (RFP) configurations. A wide range of unstable, current driven MHD modes is present in the RFP. An ideally conducting wall facing the plasma can in principle provide stabilization to these modes. However, a real, resistive wall characterized by a wall field diffusion time, cannot stabilize the ideal MHD modes unless they rotate with Alfvenic velocity, which is usually not the case. With a resistive wall, the ideal modes are converted into resistive wall modes (RWM) with growth rates comparable to the inverse wall time. Resistive wall modes have been studied in the EXTRAP T2R thin shell RFP device. Growth rates have been measured and found in agreement with linear MHD stability calculations. An advanced system for active control has been developed and installed on the EXTRAP T2R device. The system includes an array of 128 active saddle coils, fully covering the torus surface. Experiments on EXTRAP T2R have for the first time demonstrated simultaneous active suppression of multiple independent RWMs. In experiments with a partial array, coupling of different modes due to the limited number of feedback coils has been observed, in agreement with theory. Different feedback strategies, such as the intelligent shell, the rotating shell, and mode control have been studied. Further, feedback operation with different types of magnetic field sensors, measuring either the radial or the toroidal field components have been compared

  16. Quality Control for Expanded Tsetse Production, Sterilization and Field Application

    International Nuclear Information System (INIS)

    2012-07-01

    The use of the sterile insect technique (SIT) for the control of pest insects as part of an integrated, area-wide approach is widely accepted. Its application for the eradication of different tsetse flies, the vectors of human sleeping sickness and African animal trypanosomosis, is attracting increasing interest. Following several initial demonstrations of the application of the SIT for tsetse control the technique was applied on the island of Unguja, Zanzibar, in the mid-1990s and, as the final component of an integrated control programme, led to the eradication of the only tsetse species on the island, Glossina austeni. This successful programme encouraged a number of countries to embark on projects with an SIT component for tsetse control, most Ethiopia. In 2001 the Pan African Tsetse and Trypanosomosis Eradication Campaign (PATTEC) was launched by the Organization of African Unity (now African Union, AU) and, subsequently, six countries obtained funding from the African Development Bank (AfDB) in 2005 to support control programmes with an SIT component. A further six countries have subsequently requested AfDB funding for their programmes. The FAO/IAEA coordinated research project (CRP) on Automation for Tsetse Mass Rearing For Use in Sterile Insect Technique Programmes, which was completed in 2001, led to the development of a semi-automated system for tsetse production. Using this new system, a large rearing facility was established in Addis Ababa, Ethiopia, to supply sterile males for an elimination programme in the southern Rift Valley. The development of large-scale rearing highlighted the need for improved quality control procedures and, with this in mind, the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture established a CRP in 2003 entitled Improved and Harmonized Quality Control for Expanded Tsetse Production, Sterilization and Field Application with the Objective of Improving and Expanding the Quality Control Sections of the FAO

  17. Quality Control for Expanded Tsetse Production, Sterilization and Field Application

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-15

    The use of the sterile insect technique (SIT) for the control of pest insects as part of an integrated, area-wide approach is widely accepted. Its application for the eradication of different tsetse flies, the vectors of human sleeping sickness and African animal trypanosomosis, is attracting increasing interest. Following several initial demonstrations of the application of the SIT for tsetse control the technique was applied on the island of Unguja, Zanzibar, in the mid-1990s and, as the final component of an integrated control programme, led to the eradication of the only tsetse species on the island, Glossina austeni. This successful programme encouraged a number of countries to embark on projects with an SIT component for tsetse control, most Ethiopia. In 2001 the Pan African Tsetse and Trypanosomosis Eradication Campaign (PATTEC) was launched by the Organization of African Unity (now African Union, AU) and, subsequently, six countries obtained funding from the African Development Bank (AfDB) in 2005 to support control programmes with an SIT component. A further six countries have subsequently requested AfDB funding for their programmes. The FAO/IAEA coordinated research project (CRP) on Automation for Tsetse Mass Rearing For Use in Sterile Insect Technique Programmes, which was completed in 2001, led to the development of a semi-automated system for tsetse production. Using this new system, a large rearing facility was established in Addis Ababa, Ethiopia, to supply sterile males for an elimination programme in the southern Rift Valley. The development of large-scale rearing highlighted the need for improved quality control procedures and, with this in mind, the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture established a CRP in 2003 entitled Improved and Harmonized Quality Control for Expanded Tsetse Production, Sterilization and Field Application with the Objective of Improving and Expanding the Quality Control Sections of the FAO

  18. Volcanic Monitoring Techniques Applied to Controlled Fragmentation Experiments

    Science.gov (United States)

    Kueppers, U.; Alatorre-Ibarguengoitia, M. A.; Hort, M. K.; Kremers, S.; Meier, K.; Scharff, L.; Scheu, B.; Taddeucci, J.; Dingwell, D. B.

    2010-12-01

    Volcanic eruptions are an inevitable natural threat. The range of eruptive styles is large and short term fluctuations of explosivity or vent position pose a large risk that is not necessarily confined to the immediate vicinity of a volcano. Explosive eruptions rather may also affect aviation, infrastructure and climate, regionally as well as globally. Multiparameter monitoring networks are deployed on many active volcanoes to record signs of magmatic processes and help elucidate the secrets of volcanic phenomena. However, our mechanistic understanding of many processes hiding in recorded signals is still poor. As a direct consequence, a solid interpretation of the state of a volcano is still a challenge. In an attempt to bridge this gap, we combined volcanic monitoring and experimental volcanology. We performed 15 well-monitored, field-based, experiments and fragmented natural rock samples from Colima volcano (Mexico) by rapid decompression. We used cylindrical samples of 60 mm height and 25 mm and 60 mm diameter, respectively, and 25 and 35 vol.% open porosity. The applied pressure range was from 4 to 18 MPa. Using different experimental set-ups, the pressurised volume above the samples ranged from 60 - 170 cm3. The experiments were performed at ambient conditions and at controlled sample porosity and size, confinement geometry, and applied pressure. The experiments have been thoroughly monitored with 1) Doppler Radar (DR), 2) high-speed and high-definition cameras, 3) acoustic and infrasound sensors, 4) pressure transducers, and 5) electrically conducting wires. Our aim was to check for common results achieved by the different approaches and, if so, calibrate state-of-the-art monitoring tools. We present how the velocity of the ejected pyroclasts was measured by and evaluated for the different approaches and how it was affected by the experimental conditions and sample characteristics. We show that all deployed instruments successfully measured the pyroclast

  19. A bioenergetics-kinetics coupled modeling study on subsurface microbial metabolism in a field biostimulation experiment

    Science.gov (United States)

    Jin, Q.; Zheng, Z.; Zhu, C.

    2006-12-01

    Microorganisms in nature conserve energy by catalyzing various geochemical reactions. To build a quantitative relationship between geochemical conditions and metabolic rates, we propose a bioenergetics-kinetics coupled modeling approach. This approach describes microbial community as a metabolic network, i.e., fermenting microbes degrade organic substrates while aerobic respirer, nitrate reducer, metal reducer, sulfate reducer, and methanogen consume the fermentation products. It quantifies the control of substrate availability and biological energy conservation on the metabolic rates using thermodynamically consistent rate laws. We applied this simulation approach to study the progress of microbial metabolism during a field biostimulation experiment conducted in Oak Ridge, Tennessee. In the experiment, ethanol was injected into a monitoring well and groundwater was sampled to monitor changes in the chemistry. With time, concentrations of ethanol and SO42- decreased while those of NH4+, Fe2+, and Mn2+ increased. The simulation results fitted well to the observation, indicating simultaneous ethanol degradation and terminal electron accepting processes. The rates of aerobic respiration and denitrification were mainly controlled by substrate concentrations while those of ethanol degradation, sulfate reduction, and methanogenesis were controlled dominantly by the energy availability. The simulation results suggested two different microbial growth statuses in the subsurface. For the functional groups with significant growth, variations with time in substrate concentrations demonstrated a typical S curve. For the groups without significant growth, initial decreases in substrate concentrations were linear with time. Injecting substrates followed by monitoring environmental chemistry therefore provides a convenient approach to characterize microbial growth in the subsurface where methods for direct observation are currently unavailable. This research was funded by the

  20. Controlled soil warming powered by alternative energy for remote field sites.

    Science.gov (United States)

    Johnstone, Jill F; Henkelman, Jonathan; Allen, Kirsten; Helgason, Warren; Bedard-Haughn, Angela

    2013-01-01

    Experiments using controlled manipulation of climate variables in the field are critical for developing and testing mechanistic models of ecosystem responses to climate change. Despite rapid changes in climate observed in many high latitude and high altitude environments, controlled manipulations in these remote regions have largely been limited to passive experimental methods with variable effects on environmental factors. In this study, we tested a method of controlled soil warming suitable for remote field locations that can be powered using alternative energy sources. The design was tested in high latitude, alpine tundra of southern Yukon Territory, Canada, in 2010 and 2011. Electrical warming probes were inserted vertically in the near-surface soil and powered with photovoltaics attached to a monitoring and control system. The warming manipulation achieved a stable target warming of 1.3 to 2 °C in 1 m(2) plots while minimizing disturbance to soil and vegetation. Active control of power output in the warming plots allowed the treatment to closely match spatial and temporal variations in soil temperature while optimizing system performance during periods of low power supply. Active soil heating with vertical electric probes powered by alternative energy is a viable option for remote sites and presents a low-disturbance option for soil warming experiments. This active heating design provides a valuable tool for examining the impacts of soil warming on ecosystem processes.

  1. Controlled soil warming powered by alternative energy for remote field sites.

    Directory of Open Access Journals (Sweden)

    Jill F Johnstone

    Full Text Available Experiments using controlled manipulation of climate variables in the field are critical for developing and testing mechanistic models of ecosystem responses to climate change. Despite rapid changes in climate observed in many high latitude and high altitude environments, controlled manipulations in these remote regions have largely been limited to passive experimental methods with variable effects on environmental factors. In this study, we tested a method of controlled soil warming suitable for remote field locations that can be powered using alternative energy sources. The design was tested in high latitude, alpine tundra of southern Yukon Territory, Canada, in 2010 and 2011. Electrical warming probes were inserted vertically in the near-surface soil and powered with photovoltaics attached to a monitoring and control system. The warming manipulation achieved a stable target warming of 1.3 to 2 °C in 1 m(2 plots while minimizing disturbance to soil and vegetation. Active control of power output in the warming plots allowed the treatment to closely match spatial and temporal variations in soil temperature while optimizing system performance during periods of low power supply. Active soil heating with vertical electric probes powered by alternative energy is a viable option for remote sites and presents a low-disturbance option for soil warming experiments. This active heating design provides a valuable tool for examining the impacts of soil warming on ecosystem processes.

  2. Low frequency sound field control for loudspeakers in rectangular rooms using CABS (Controlled Acoustical Bass System)

    DEFF Research Database (Denmark)

    Nielsen, Sofus Birkedal; Celestinos, Adrian

    2010-01-01

    Rectangular rooms are the most common shape for sound reproduction, but at low frequencies the reflections from the boundaries of the room cause large spatial variations in the sound pressure level.  Variations up to 30 dB are normal, not only at the room modes, but basically at all frequencies....... As sound propagates in time, it seems natural that the problems can best be analyzed and solved in the time domain. A time based room correction system named CABS (Controlled Acoustical Bass System) has been developed for sound reproduction in rectangular listening rooms. It can control the sound...... sound field in the whole room, and short impulse response.  In a standard listening room (180 m3) only 4 loudspeakers are needed, 2 more than a traditional stereo setup. CABS is controlled by a developed DSP system. The time based approached might help with the understanding of sound field control...

  3. Y2K experiences in the nuclear material control area

    International Nuclear Information System (INIS)

    Yagi, T.; Suzuki, T.

    1999-01-01

    Though the Y2K problem was treated by each organization, it became systematic in Japan when Advanced Information and Telecommunication Society Promotion Head-quarters was established recognizing the importance and urgency of the issue. The summary of the action and some experiences concerning Y2K issues in the nuclear materials control area are presented

  4. Control and interpretation of criticality experiments on metallic assemblies

    International Nuclear Information System (INIS)

    Long, J.J.

    1984-01-01

    This paper deals with the principle of criticality experiment control with approach machines; to follow the reactivity evolution, one uses the classical method of the inverses of counting rates, then one shows how it is possible to extrapolate the approach curves that have been obtained [fr

  5. The VEPP-2000 Collider Control System: Operational Experience

    CERN Document Server

    Senchenko, A I; Lysenko, A P; Rogovsky, Yu A; Shatunov, P Yu

    2017-01-01

    The VEPP-2000 collider was commissioned and operated successfully in 2010-2013. During the operation the facility underwent continuous updates and experience in maintenance was acquired. Strong cooperation between the staff of the accelerator complex and the developers of the control system proved effective for implementing the necessary changes in a short time.

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

    International Nuclear Information System (INIS)

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

    1997-01-01

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

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

    Science.gov (United States)

    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

  8. Pre-study of burn control in Tokamak reactor experiments

    International Nuclear Information System (INIS)

    Elevant, T.; Anderson, D.; Hamnen, H.; Lisak, M.

    1991-04-01

    Findings from a general study of issues associated with control of burning fusion plasmas are reported, and applications to ITER are given. A number of control variables are discussed. A zerodimensional system has been developed and stability against coupled temperature and density variations are studied. Also space dependent energy balance and transition to thermonuclear burn are analysed as well as maximum obtainable Q-values under subignited operation conditions. Control designs with different input-output strategies are analysed and numerically simulated, and a numerical experiment of system identification is made. Requirements on diagnostics are discussed and areas for further studies are identified. (au) (64 refs.)

  9. Evaluation of Alternative Field Buses for Lighting ControlApplications

    Energy Technology Data Exchange (ETDEWEB)

    Koch, Ed; Rubinstein, Francis

    2005-03-21

    The Subcontract Statement of Work consists of two major tasks. This report is the Final Report in fulfillment of the contract deliverable for Task 1. The purpose of Task 1 was to evaluate existing and emerging protocols and standards for interfacing sensors and controllers for communicating with integrated lighting control systems in commercial buildings. The detailed task description follows: Task 1. Evaluate alternative sensor/field buses. The objective of this task is to evaluate existing and emerging standards for interfacing sensors and controllers for communicating with integrated lighting control systems in commercial buildings. The protocols to be evaluated will include at least: (1) 1-Wire Net, (2) DALI, (3) MODBUS (or appropriate substitute such as EIB) and (4) ZigBee. The evaluation will include a comparative matrix for comparing the technical performance features of the different alternative systems. The performance features to be considered include: (1) directionality and network speed, (2) error control, (3) latency times, (4) allowable cable voltage drop, (5) topology, and (6) polarization. Specifically, Subcontractor will: (1) Analyze the proposed network architecture and identify potential problems that may require further research and specification. (2) Help identify and specify additional software and hardware components that may be required for the communications network to operate properly. (3) Identify areas of the architecture that can benefit from existing standards and technology and enumerate those standards and technologies. (4) Identify existing companies that may have relevant technology that can be applied to this research. (5) Help determine if new standards or technologies need to be developed.

  10. A Demonstration Experiment for the Forecast of Magnetic Field and Field Errors in the Large Hadron Collider

    CERN Document Server

    Sammut, N J; Bottura, L; Deferne, G; Lamont, M; Miles, J; Sanfilippo, S; Strzelczyk, M; Venturini-Delsolaro, W; Xydi, P

    2008-01-01

    In order to reduce the burden on the beam-based feedback, the Large Hadron Collider control system is equipped with the Field Description for the LHC (FiDeL) which provides a forecast of the magnetic field and the multipole field errors. FiDeL has recently been extensively tested at CERN to determine main field tracking, multipole forecasting and compensation accuracy. This paper describes the rationale behind the tests, the procedures employed to power the main magnets and their correctors, and finally, we present the results obtained. We also give an indication of the prediction accuracy that the system can deliver during the operation of the LHC and we discuss the implications that these will have on the machine performance.

  11. Overview of BELGATOM's industrial experience in the field of radwaste bituminization, cementation and radwaste package storage

    International Nuclear Information System (INIS)

    Glibert, R.; Debieve, P.; Averbeke, J. van; Centner, B.

    1993-01-01

    Radioactive waste processing experience in Belgium is introduced. BELGATOM partners in Belgium have accumulated experience for over 25 years in the field of rad waste treatment and conditioning by bituminization and cementation and in the storage of the resulting rad waste packages

  12. A large scale field experiment in the Amazon basin (LAMBADA/BATERISTA)

    NARCIS (Netherlands)

    Dolman, A.J.; Kabat, P.; Gash, J.H.C.; Noilhan, J.; Jochum, A.M.; Nobre, C.

    1995-01-01

    A description is given of a large-scale field experiment planned in the Amazon basin, aimed at assessing the large-scale balances of energy, water and carbon dioxide. The embedding of this experiment in global change programmes is described, viz. the Biospheric Aspects of the Hydrological Cycle

  13. Developing Standards-Based Geography Curricular Materials from Overseas Field Experiences for K-12 Teachers

    Science.gov (United States)

    Oberle, Alex; Palacios, Fabian Araya

    2012-01-01

    Overseas experiences provide educators with exceptional opportunities to incorporate field study, firsthand experiences, and tangible artifacts into the classroom. Despite this potential, teachers must consider curricular standards that direct how such international endeavors can be integrated. Furthermore, geography curriculum development is more…

  14. Sound Design in Virtual Reality Concert Experiences using a Wave Field Synthesis Approach

    DEFF Research Database (Denmark)

    Lind, Rasmus Bloustrød; Milesen, Victor; Smed, Dina Madsen

    2017-01-01

    In this paper we propose an experiment that evaluates the influence of audience noise on the feeling of presence and the perceived quality in a virtual reality concert experience delivered using Wave Field Synthesis. A 360 degree video of a live rock concert from a local band was recorded. Single...

  15. Entering the Field: Beginning Teachers' Positioning Experiences of the Staffroom

    Science.gov (United States)

    Christensen, Erin; Rossi, Tony; lisahunter; Tinning, Richard

    2018-01-01

    Little is known about beginning teachers' political positioning experiences of the staffroom. This paper employs Bourdieu's conceptual tools of field, habitus and capital to explore beginning health and physical education teachers' positioning experiences and learning in staffrooms, the place in which teachers spend the majority of their…

  16. Nanomechanical control of optical field and quality factor in photonic crystal structures

    Science.gov (United States)

    Cotrufo, Michele; Midolo, Leonardo; Zobenica, Žarko; Petruzzella, Maurangelo; van Otten, Frank W. M.; Fiore, Andrea

    2018-03-01

    Actively controlling the properties of localized optical modes is crucial for cavity quantum electrodynamics experiments. While several methods to tune the optical frequency have been demonstrated, the possibility of controlling the shape of the modes has scarcely been investigated. Yet an active manipulation of the mode pattern would allow direct control of the mode volume and the quality factor and therefore of the radiative processes. In this work, we propose and demonstrate a nano-optoelectromechanical device in which a mechanical displacement affects the spatial pattern of the electromagnetic field. The device is based on a double-membrane photonic crystal waveguide which, upon bending, creates a spatial modulation of the effective refractive index, resulting in an effective potential well or antiwell for the optical modes. The change in the field pattern drastically affects the optical losses: large modulations of the quality factors and dissipative coupling rates larger than 1 GHz/nm are predicted by calculations and confirmed by experiments. This concept opens new avenues in solid-state cavity quantum electrodynamics in which the field, instead of the frequency, is coupled to the mechanical motion.

  17. Divertor experiments in a toroidal plasma, with E x B drift due to an applied radial electric field

    International Nuclear Information System (INIS)

    Strait, E.J.

    1979-09-01

    It is proposed that the E x B drift arising from an externally applied electric field could be used in a tokamak or other toroidal magnetic plasma confinement device to remove plasma and impurities from the region near the wall and reduce the amount of plasma striking the wall. This could either augment or replace a conventional magnetic field divertor. Among the possible advantages of this scheme are easy external control over the rate of removal of plasma, more rapid removal than the naturally occurring rate in a magnetic divertor, and simplification of construction if the magnetic divertor is eliminated. Results of several related experiments performed in the Wisconsin Levitated Octupole are presented

  18. Simulation and design of feedback control on resistive wall modes in Keda Torus eXperiment

    International Nuclear Information System (INIS)

    Li, Chenguang; Liu, Wandong; Li, Hong

    2014-01-01

    The feedback control of resistive wall modes (RWMs) in Keda Torus eXperiment (KTX) (Liu et al., Plasma Phys. Controlled Fusion 56, 094009 (2014)) is investigated by simulation. A linear model is built to describe the growth of the unstable modes in the absence of feedback and the resulting mode suppression due to feedback, given the typical reversed field pinch plasma equilibrium. The layout of KTX with two shell structures (the vacuum vessel and the stabilizing shell) is taken into account. The feedback performance is explored both in the scheme of “clean mode control” (Zanca et al., Nucl. Fusion 47, 1425 (2007)) and “raw mode control.” The discrete time control model with specific characteristic times will mimic the real feedback control action and lead to the favored control cycle. Moreover, the conceptual design of feedback control system is also presented, targeting on both RWMs and tearing modes

  19. Experience feedback of computerized controlled nuclear power plants

    International Nuclear Information System (INIS)

    Poizat, F.

    2004-01-01

    The N4 step of French PWR-type nuclear power plants is characterized by an instrumentation and control system entirely computerized (operation procedures including normal and accidental operation). Four power plants of this type (Chooz and Civaux sites) of 1450 MWe each were connected to the power grid between August 1996 and December 1999. The achievement of this program make it possible and necessary to carry out an experience feedback about the development, successes and difficulties encountered in order to draw out some lessons for future realizations. This is the aim of this article: 1 - usefulness and difficulties of such an experience feedback: evolution of instrumentation and control systems, necessary cautions; 2 - a successful computerized control: checking of systems operation, advantages, expectations; 3 - efficiency of computerized systems: demonstration of operation safety, profitability; 4 - conclusions and interrogations: system approach instead of 'micro-software' approach, commercial or 'made to measure' products, contract agreement with a supplier, when and how upgrading. (J.S.)

  20. Assuring robustness to noise in optimal quantum control experiments

    International Nuclear Information System (INIS)

    Bartelt, A.F.; Roth, M.; Mehendale, M.; Rabitz, H.

    2005-01-01

    Closed-loop optimal quantum control experiments operate in the inherent presence of laser noise. In many applications, attaining high quality results [i.e., a high signal-to-noise (S/N) ratio for the optimized objective] is as important as producing a high control yield. Enhancement of the S/N ratio will typically be in competition with the mean signal, however, the latter competition can be balanced by biasing the optimization experiments towards higher mean yields while retaining a good S/N ratio. Other strategies can also direct the optimization to reduce the standard deviation of the statistical signal distribution. The ability to enhance the S/N ratio through an optimized choice of the control is demonstrated for two condensed phase model systems: second harmonic generation in a nonlinear optical crystal and stimulated emission pumping in a dye solution

  1. CTEPP STANDARD OPERATING PROCEDURE FOR CONDUCTING INTERNAL FIELD AUDITS AND QUALITY CONTROL (SOP-2.25)

    Science.gov (United States)

    This SOP describes the method for conducting internal field audits and quality control procedures. Internal field audits will be conducted to ensure the collection of high quality data. Internal field audits will be conducted by Field Auditors (the Field QA Officer and the Field...

  2. Effectiveness of subsidies in promoting healthy food purchases and consumption: a review of field experiments.

    Science.gov (United States)

    An, Ruopeng

    2013-07-01

    To systematically review evidence from field interventions on the effectiveness of monetary subsidies in promoting healthier food purchases and consumption. Keyword and reference searches were conducted in five electronic databases: Cochrane Library, EconLit, MEDLINE, PsycINFO and Web of Science. Studies were included based on the following criteria: (i) intervention: field experiments; (ii) population: adolescents 12–17 years old or adults 18 years and older; (iii) design: randomized controlled trials, cohort studies or pre–post studies; (iv) subsidy: price discounts or vouchers for healthier foods; (v) outcome: food purchases or consumption; (vi) period: 1990–2012; and (vii) language: English. Twenty-four articles on twenty distinct experiments were included with study quality assessed using predefined methodological criteria. Interventions were conducted in seven countries: the USA (n 14), Canada (n 1), France (n 1), Germany (n 1), Netherlands (n 1), South Africa (n 1) and the UK (n 1). Subsidies applied to different types of foods such as fruits, vegetables and low-fat snacks sold in supermarkets, cafeterias, vending machines, farmers’ markets or restaurants. Interventions enrolled various population subgroups such as school/ university students, metropolitan transit workers and low-income women. All but one study found subsidies on healthier foods to significantly increase the purchase and consumption of promoted products. Study limitations include small and convenience samples, short intervention and follow-up duration, and lack of cost-effectiveness and overall diet assessment. Subsidizing healthier foods tends to be effective in modifying dietary behaviour. Future studies should examine its long-term effectiveness and cost-effectiveness at the population level and its impact on overall diet intake.

  3. Virtual navigation performance: the relationship to field of view and prior video gaming experience.

    Science.gov (United States)

    Richardson, Anthony E; Collaer, Marcia L

    2011-04-01

    Two experiments examined whether learning a virtual environment was influenced by field of view and how it related to prior video gaming experience. In the first experiment, participants (42 men, 39 women; M age = 19.5 yr., SD = 1.8) performed worse on a spatial orientation task displayed with a narrow field of view in comparison to medium and wide field-of-view displays. Counter to initial hypotheses, wide field-of-view displays did not improve performance over medium displays, and this was replicated in a second experiment (30 men, 30 women; M age = 20.4 yr., SD = 1.9) presenting a more complex learning environment. Self-reported video gaming experience correlated with several spatial tasks: virtual environment pointing and tests of Judgment of Line Angle and Position, mental rotation, and Useful Field of View (with correlations between .31 and .45). When prior video gaming experience was included as a covariate, sex differences in spatial tasks disappeared.

  4. Rocket to Creativity: A Field Experience in Problem-Based and Project-Based Learning

    Directory of Open Access Journals (Sweden)

    Sharon F. Dole

    2016-11-01

    Full Text Available The purpose of this article is to examine the impact of a field experience in problem-based (PBL and project-based learning (PjBL on pre-service and in-service teachers’ conceptions of experiential learning. In our study, participants had been enrolled in a hybrid class that included an online component in which they learned about PBL and PjBL and an experiential component in which they facilitated PBL and PjBL with children in grades 1-9 during a one-week field experience on a university campus. The goal of the field experience is for teachers to change their practice from didactic to inquiry and to promote critical and creative thinking in their students. We used a case study method that involved data derived from six different sources: online structured interviews, follow-up telephone interviews, discussion board posts, reflections, course feedback, and observations. The main theme that emerged from the data analysis was the critical role the field experience played in applying theory to practice. Sub-themes included understanding the process of implementing PBL and PjBL, mastering the logistics of PBL and PjBL, becoming facilitators, and collaborating with partners. Results showed that the field experience gave the teachers the “courage” to experiment with a student-centered methodology.

  5. Multistate nonvolatile straintronics controlled by a lateral electric field

    International Nuclear Information System (INIS)

    Iurchuk, V; Doudin, B; Kundys, B

    2014-01-01

    We present a multifunctional and multistate permanent memory device based on lateral electric field control of a strained surface. Sub-coercive electrical writing of a remnant strain of a PZT substrate imprints stable and rewritable resistance changes on a CoFe overlayer. A proof-of-principle device, with the simplest resistance strain gage design, is shown as a memory cell exhibiting 17-memory states of high reproducibility and reliability for nonvolatile operations. Magnetoresistance of the film also depends on the cell state, and indicates a rewritable change of magnetic properties persisting in the remnant strain of the substrate. This makes it possible to combine strain, magnetic and resistive functionalities in a single memory element, and suggests that sub-coercive stress studies are of interest for straintronics applications. (fast track communication)

  6. Multistate nonvolatile straintronics controlled by a lateral electric field.

    Science.gov (United States)

    Iurchuk, V; Doudin, B; Kundys, B

    2014-07-23

    We present a multifunctional and multistate permanent memory device based on lateral electric field control of a strained surface. Sub-coercive electrical writing of a remnant strain of a PZT substrate imprints stable and rewritable resistance changes on a CoFe overlayer. A proof-of-principle device, with the simplest resistance strain gage design, is shown as a memory cell exhibiting 17-memory states of high reproducibility and reliability for nonvolatile operations. Magnetoresistance of the film also depends on the cell state, and indicates a rewritable change of magnetic properties persisting in the remnant strain of the substrate. This makes it possible to combine strain, magnetic and resistive functionalities in a single memory element, and suggests that sub-coercive stress studies are of interest for straintronics applications.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Moses J. Chimbari

    2012-01-01

    Full Text Available 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.

  9. Fault-tolerant design of local controller for the poloidal field converter control system on ITER

    International Nuclear Information System (INIS)

    Shen, Jun; Fu, Peng; Gao, Ge; He, Shiying; Huang, Liansheng; Zhu, Lili; Chen, Xiaojiao

    2016-01-01

    Highlights: • The requirements on the Local Control Cubicles (LCC) for ITER Poloidal Field Converter are analyzed. • Decoupled service-based software architecture is proposed to make control loops on LCC running at varying cycle-time. • Fault detection and recovery methods for the LCC are developed to enhance the system. • The performance of the LCC with or without fault-tolerant feature is tested and compared. - Abstract: The control system for the Poloidal Field (PF) on ITER is a synchronously networked control system, which has several kinds of computational controllers. The Local Control Cubicles (LCC) play a critical role in the networked control system for they are the interface to all input and output signals. Thus, some additional work must be done to guarantee the LCCs proper operation under influence of faults. This paper mainly analyzes the system demands of the LCCs and faults which have been encountered recently. In order to handle these faults, decoupled service-based software architecture has been proposed. Based on this architecture, fault detection and system recovery methods, such as redundancy and rejuvenation, have been incorporated to achieve a fault-tolerant private network with the aid of QNX operating system. Unlike the conventional method, this method requires no additional hardware and can be achieved relatively easily. To demonstrate effectiveness the LCCs have been successfully tested during the recent PF Converter Unit performance tests for ITER.

  10. Fault-tolerant design of local controller for the poloidal field converter control system on ITER

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Jun; Fu, Peng; Gao, Ge; He, Shiying; Huang, Liansheng, E-mail: huangls@ipp.ac.cn; Zhu, Lili; Chen, Xiaojiao

    2016-11-15

    Highlights: • The requirements on the Local Control Cubicles (LCC) for ITER Poloidal Field Converter are analyzed. • Decoupled service-based software architecture is proposed to make control loops on LCC running at varying cycle-time. • Fault detection and recovery methods for the LCC are developed to enhance the system. • The performance of the LCC with or without fault-tolerant feature is tested and compared. - Abstract: The control system for the Poloidal Field (PF) on ITER is a synchronously networked control system, which has several kinds of computational controllers. The Local Control Cubicles (LCC) play a critical role in the networked control system for they are the interface to all input and output signals. Thus, some additional work must be done to guarantee the LCCs proper operation under influence of faults. This paper mainly analyzes the system demands of the LCCs and faults which have been encountered recently. In order to handle these faults, decoupled service-based software architecture has been proposed. Based on this architecture, fault detection and system recovery methods, such as redundancy and rejuvenation, have been incorporated to achieve a fault-tolerant private network with the aid of QNX operating system. Unlike the conventional method, this method requires no additional hardware and can be achieved relatively easily. To demonstrate effectiveness the LCCs have been successfully tested during the recent PF Converter Unit performance tests for ITER.

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

    Science.gov (United States)

    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. Vertical field systems in TPE-1RM15 reversed dield pinch experiment

    International Nuclear Information System (INIS)

    Shimada, T.; Hirano, Y.; Yagi, Y.; Ogawa, K.; Yamane, M.; Yamaguchi, S.; Oyabu, I.; Murakami, S.

    1989-01-01

    Design of equilibrium control system in TPE-1RM15 is described in detail, where equilibrium is maintained bij the combinatuion of the error field at shell cuts by the external vertical field with pre-programmed wave form is essential to set up and maintain RPF discharge. Control of the equilibrium position in the vacuum vessel by using DC vertical field inside the shell at the plasma break down phase, which makes it possible to operate DC vertical field in a wide range. Tooidal asymmetry of the feeders of the pulsed vertical field coil located there. This asymmetry is compensated bij the local vertical field of saddle coil wound around the shell cuts. (author). 2 refs.;4 figs

  13. The side effects of nitrification inhibitors on leaching water and soil salinization in a field experiment

    Energy Technology Data Exchange (ETDEWEB)

    Diez, J. A.; Arauzo, M.; Hernaiz, P.; Sanz, A.

    2010-07-01

    In experiments carried out in greenhouses, some authors have shown that ammonium sulphate induces greater soil acidity and salinity than other sources of N. Moreover, nitrification inhibitors (NI) tend to cause ammonium to accumulate in soil by retarding its oxidation to nitrate. This accumulated ammonium would also have an effect on soil salinity. Consequently, the aim of this paper was to evaluate the soil and leaching water salinization effects associated with adding NI, dicyandiamide (DCD) and dimethylpyrazole-phosphate (DMPP) to ammonium sulphate nitrate (ASN) fertilizer. This experiment was carried out in the field with an irrigated maize crop. Drainage and Na concentration were measured during both seasons (2006 and 2007) and leached Na was determined. The treatments with NI (DCD and DMPP) were associated with greater Na concentrations in soil solutions and consequently higher rates of Na leaching (in 2007, ASN-DCD 1,292 kg Na ha{sup -}1, ASN-DMPP 1,019 kg Na ha{sup -}1). A treatment involving only ASN also increased the Na concentration in soil and the amount of Na leached in relation to the Control (in 2007, ASN 928 kg Na ha{sup -}1 and Control 587 kg Na ha{sup -}1). The increase in the ammonium concentration in the soil due to the NI treatments could have been the result of the displacement of Na ions from the soil exchange complex through a process which finally led to an increase in soil salinity. Treatments including ammonium fertilizer formulated with NI produced a greater degree of soil salinization due to the presence of ammonium from the fertilizer and accumulated ammonium from the nitrification inhibition. (Author) 31 refs.

  14. Coupling Solute and Fine Particle Transport with Sand Bed Morphodynamics within a Field Experiment

    Science.gov (United States)

    Phillips, C. B.; Ortiz, C. P.; Schumer, R.; Jerolmack, D. J.; Packman, A. I.

    2017-12-01

    Fine suspended particles are typically considered to pass through streams and rivers as wash load without interacting with the bed, however experiments have demonstrated that hyporheic flow causes advective exchange of fine particles with the stream bed, yielding accumulation of fine particle deposits within the bed. Ultimately, understanding river morphodynamics and ecosystem dynamics requires coupling both fine particle and solute transport with bed morphodynamics. To better understand the coupling between these processes we analyze a novel dataset from a controlled field experiment conducted on Clear Run, a 2nd order sand bed stream located within the North Carolina coastal plain. Data include concentrations of continuously injected conservative solutes and fine particulate tracers measured at various depths within the stream bed, overhead time lapse images of bed forms, stream discharge, and geomorphological surveys of the stream. We use image analysis of bed morphodynamics to assess exchange, retention, and remobilization of solutes and fine particles during constant discharge and a short duration experimental flood. From the images, we extract a time series of bedform elevations and scour depths for the duration of the experiment. The high-resolution timeseries of bed elevation enables us to assess coupling of bed morphodynamics with both the solute and fine particle flux during steady state mobile bedforms prior to the flood and to changing bedforms during the flood. These data allow the application of a stochastic modeling framework relating bed elevation fluctuations to fine particle residence times. This combined experimental and modeling approach ultimately informs our ability to predict not only the fate of fine particulate matter but also associated nutrient and carbon dynamics within streams and rivers.

  15. The Current Situation of Field Experience in a Five-Year Science Teacher Education Program in Thailand

    Science.gov (United States)

    Faikhamta, Chatree; Jantarakantee, Ekgapoom; Roadrangka, Vantipa

    2011-01-01

    This research explored the current situation in managing the field experience of a five-year science teacher education program in one university in Thailand. A number of methods were used to assess field experience situation: (1) a questionnaire on the perceptions of pre-service science teachers of field experience management; (2) participant…

  16. Molten metal feed system controlled with a traveling magnetic field

    Science.gov (United States)

    Praeg, Walter F.

    1991-01-01

    A continuous metal casting system in which the feed of molten metal is controlled by means of a linear induction motor capable of producing a magnetic traveling wave in a duct that connects a reservoir of molten metal to a caster. The linear induction motor produces a traveling magnetic wave in the duct in opposition to the pressure exerted by the head of molten metal in the reservoir so that p.sub.c =p.sub.g -p.sub.m where p.sub.c is the desired pressure in the caster, p.sub.g is the gravitational pressure in the duct exerted by the force of the head of molten metal in the reservoir, and p.sub.m is the electromagnetic pressure exerted by the force of the magnetic field traveling wave produced by the linear induction motor. The invention also includes feedback loops to the linear induction motor to control the casting pressure in response to measured characteristics of the metal being cast.

  17. Greenhouse and field assessment of rhizobacteria to control guava decline

    Directory of Open Access Journals (Sweden)

    Alexandre Macedo Almeida

    2011-01-01

    Full Text Available In an effort to devise a biological strategy to control guava decline, 120 rhizobacteria isolates were obtained from symptomless guava trees located in Meloidogyne enterolobii-infested orchards. Of those isolates, 44 were assessed for their potential to reduce nematode's reproduction: for each isolate, six guava stem cuttings were embedded for eight hours with bacterial suspension and transplanted. Upon development of the roots, the plants were inoculated with 2000 nematode eggs and allowed to grow for four months under greenhouse. Seedlings embedded with water, inoculated or not with the nematode, served as controls. All treatments were equivalent in the five variables that assessed plant development. Several rhizobacteria reduced (p<0.05 the final nematode population (Fp, Fp/gram of root and reproduction factor, although not to satisfactory levels. Subsequently, a two-year experiment was set up in a guava orchard affected by guava decline, in which three of the most effective rhizobacterial isolates were compared with the biological products Nemat® and Nemaplus® for their ability to reduce variables related to nematode parasitism and increase guava productivity. Seven bimonthly applications of these treatments under the tree canopy were unable to reduce nematode parasitism and increase productivity. The decline and death of some plants forced the experiment to be stopped after the first harvest. In conclusion, rhizobacteria applications seem unable to reduce the parasitism of M. enterolobii on guava plants, and even less to reduce the extensive root decay or alleviate the physiological stress suffered by trees affected by guava decline.

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

    Science.gov (United States)

    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.

  19. Variably Saturated Flow and Multicomponent Biogeochemical Reactive Transport Modeling of a Uranium Bioremediation Field Experiment

    International Nuclear Information System (INIS)

    Yabusaki, Steven B.; Fang, Yilin; Williams, Kenneth H.; Murray, Christopher J.; Ward, Anderson L.; Dayvault, Richard; Waichler, Scott R.; Newcomer, Darrell R.; Spane, Frank A.; Long, Philip E.

    2011-01-01

    Field experiments at a former uranium mill tailings site have identified the potential for stimulating indigenous bacteria to catalyze the conversion of aqueous uranium in the +6 oxidation state to immobile solid-associated uranium in the +4 oxidation state. This effectively removes uranium from solution resulting in groundwater concentrations below actionable standards. Three-dimensional, coupled variably-saturated flow and biogeochemical reactive transport modeling of a 2008 in situ uranium bioremediation field experiment is used to better understand the interplay of transport rates and biogeochemical reaction rates that determine the location and magnitude of key reaction products. A comprehensive reaction network, developed largely through previous 1-D modeling studies, was used to simulate the impacts on uranium behavior of pulsed acetate amendment, seasonal water table variation, spatially-variable physical (hydraulic conductivity, porosity) and geochemical (reactive surface area) material properties. A principal challenge is the mechanistic representation of biologically-mediated terminal electron acceptor process (TEAP) reactions whose products significantly alter geochemical controls on uranium mobility through increases in pH, alkalinity, exchangeable cations, and highly reactive reduction products. In general, these simulations of the 2008 Big Rusty acetate biostimulation field experiment in Rifle, Colorado confirmed previously identified behaviors including (1) initial dominance by iron reducing bacteria that concomitantly reduce aqueous U(VI), (2) sulfate reducing bacteria that become dominant after ∼30 days and outcompete iron reducers for the acetate electron donor, (3) continuing iron-reducer activity and U(VI) bioreduction during dominantly sulfate reducing conditions, and (4) lower apparent U(VI) removal from groundwater during dominantly sulfate reducing conditions. New knowledge on simultaneously active metal and sulfate reducers has been

  20. Experience with control valve cavitation problems and their solutions

    International Nuclear Information System (INIS)

    Ozol, J.

    1988-01-01

    Pressure reduction in control valves can induce cavitation, which has three effects on the control valve. Firstly, it modifies or changes the hydraulic performance of the control valve. Since control valves are designed for noncavitating conditions, the result is usually reduced stability of the control valve or, in extreme cavitating conditions known as supercavitation, the valve may limit the flow rate and thus be undersized. Secondly, cavitation can cause material damage to valve parts, trim, or valve body, or erodes downstream piping; consequently, the valve or piping leaks. Thirdly, cavitation causes noise and vibration, which may cause major damage or destruction to equipment such as valve positioners, actuators, pipe supports and sometimes to other downstream valves. The purpose of this paper is twofold: (1) It describes the I.S.A. valve sizing equations and how they relate to cavitation. (2) It describes experiences with these three problems, and discusses corrective actions and practical approaches to their solution. This paper discusses thirteen cavitation experiences