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

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.

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...

Initial Design of the 60 Megawatt Rotating Magnetic Field (RMF) Oscillator System for the University of Washington ''TCS'' Field Reversed Configuration Experiment

International Nuclear Information System (INIS)

Reass, W.A.; Miera, D.A.; Wurden, G.A.

1997-01-01

This paper presents the initial electrical and mechanical design of two phase-locked 30 Megawatt RMS, 150 kHz oscillator systems used for current drive and plasma sustainment of the ''Translation, Confinement, and Sustainment'' (TCS) field reversed configuration (FRC) plasma. By the application of orthogonally-placed saddle coils on the surface of the glass vacuum vessel, the phase-controlled rotating magnetic field perturbation will induce an electric field in the plasma which should counter the intrinsic ohmic decay of the plasma, and maintain the FRC. Each system utilizes a bank of 6 parallel magnetically beamed ML8618 triodes. These devices are rated at 250 Amperes cathode current and a 45 kV plate voltage. An advantage of the magnetically beamed triode is their extreme efficiency, requiring only 2.5 kW of filament and a few amps and a few kV of grid drive. Each 3.5 uH saddle coil is configured with an adjustable tank circuit (for tuning). Assuming no losses and a nominal 18 kV plate voltage, the tubes can circulate about 30 kV and 9 kA (pk to pk) in the saddle coil antenna, a circulating power of over 33 megawatts RMS. On each cycle the tubes can kick in up to 1500 Amperes, providing a robust phase control. DC high-voltage from the tubes is isolated from the saddle coil antennas and tank circuits by a 1:1 coaxial air-core balun transformer. To control the ML8618's phase and amplitude, fast 150 Ampere ''totem-pole'' grid drivers, an ''on'' hot-deck and an ''off'' hot-deck are utilized. The hot-decks use up to 6 each 3CPX1500A7 slotted radial beam triodes. By adjusting the conduction angle, amplitude may be regulated, with inter-pulse timing, phase angle can be controlled. A central feedback timing chassis monitors each systems' saddle coil antenna and appropriately derives each systems timing signals. Fiber-optic cables are used to isolate between the control room timing chassis and the remote power oscillator system. Complete system design detail will be

Field-reversal experiments in the mirror fusion test facility (MFTF)

International Nuclear Information System (INIS)

Shearer, J.W.; Condit, W.C.

1977-01-01

Detailed consideration of several aspects of a field-reversal experiment was begun in the Mirror Fusion Test Facility (MFTF): Model calculations have provided some plausible parameters for a field-reversed deuterium plasma in the MFTF, and a buildup calculation indicates that the MFTF neutral-beam system is marginally sufficient to achieve field reversal by neutral injection alone. However, the many uncertainties indicate the need for further research and development on alternate buildup methods. A discussion of experimental objectives is presented and important diagnostics are listed. The range of parameter space accessible with the MFTF magnet design is explored, and we find that with proper aiming of the neutral beams, meaningful experiments can be performed to advance toward these objectives. Finally, it is pointed out that if we achieve enhanced n tau confinement by means of field reversal, then quasi-steady-state operation of MFTF is conceivable

Advanced ultrasonic field system: a status report

International Nuclear Information System (INIS)

Mikesell, C.R.; Beller, L.S.

1984-02-01

An advanced ultrasonic system was developed to obtain highly reproducible inspection data and to overcome certain limitations encountered with the manual scanning method. Experience from field operations from 1976 through 1980 is discussed. The scope includes a description of the computer controlled system, personnel training, inservice inspections, data analysis, and current upgrading of the system

Assessment of Field Experience Related to Pressurized Water Reactor Primary System Leaks

International Nuclear Information System (INIS)

Ware, A.G.; Hsu, C.; Atwood, C.L.; Sattison, M.B.; Hartley, R.S.; Shah, V.N.

1999-01-01

This paper presents our assessment of field experience related to pressurized water reactor (PWR) primary system leaks in terms of their number and rates, how aging affects frequency of leak events, the safety significance of such leaks, industry efforts to reduce leaks, and effectiveness of current leak detection systems. We have reviewed the licensee event reports to identify the events that took place during 1985 to the third quarter of 1996, and reviewed related technical literature and visited PWR plants to analyze these events. Our assessment shows that USNRC licensees have taken effective actions to reduce the number of leak events. One main reason for this decreasing trend was the elimination or reportable leakages from valve stem packing after 1991. Our review of leak events related to vibratory fatigue reveals a statistically significant decreasing trend with age (years of operation), but not in calendar time. Our assessment of worldwide data on leakage caused by thermal fatigue cracking is that the fatigue of aging piping is a safety significant issue. Our review of leak events has identified several susceptible sites in piping having high safety significance; but the inspection of some of these sites is not required by the ASME Code. These sites may be included in the risk-informed inspection programs

Assessment of Field Experience Related to Pressurized Water Reactor Primary System Leaks

International Nuclear Information System (INIS)

Shah, Vikram Naginbhai; Ware, Arthur Gates; Atwood, Corwin Lee; Sattison, Martin Blaine; Hartley, Robert Scott; Hsu, C.

1999-01-01

This paper presents our assessment of field experience related to pressurized water reactor (PWR) primary system leaks in terms of their number of rates, how aging affects frequency of leak events, the safety significance of such leaks, industry efforts to reduce leaks, and effectiveness of current leak detection systems. We have reviewed the licensee event reports to identify the events that took place during 1985 to the third quarter of 1996, and reviewed related technical literature and visited PWR plants to analyze these events. Our assessment shows that USNRC licensees have taken effective actions to reduce the number of leak events. One main reason for this decreasing trend was the elimination or reportable leakages from valve stem packing after 1991. Our review of leak events related to vibratory fatigue reveals a statistically significant decreasing trend with age (years of operation), but not in calendar time. Our assessment of worldwide data on leakage caused by thermal fatigue cracking is that the fatigue of aging piping is a safety significant issue. Our review of leak events has identified several susceptible sites in piping having high safety significance; but the inspection of some of these sites is not required by the ASME Code. These sites may be included in the risk-informed inspection programs

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

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

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

Experience of the pilot implementation of the european information sharing and alerting system in the field of information security

Directory of Open Access Journals (Sweden)

Anatoly A. Malyuk

2018-03-01

Full Text Available The formation of a global information society poses a particular challenge to the development of an information security culture. In the Doctrine of Information Security of the Russian Federation, adopted in December 2016, one of the main threats is the low awareness of citizens in matters of ensuring personal information security. One of the most important mechanisms for increasing competence and forming an in-formation security culture, in addition to mass training of people, are methods of propaganda and creation of "hot lines". They allow the general public to take the initiative in monitoring and reporting computer incidents. The development of such approaches should be carried out taking into account the international experience accumulated today. To this end, the article examines the European experience of creating a system of information and advisory assistance in the field of preventing threats to the security of public and corporate information systems, primarily information and telecommunications networks, as well as eliminating the consequences of threats in the information sphere. The analysis of the experience of implementing the pilot project of the European Information Sharing and Alert System has revealed the advisability of designing such systems on the basis of a management model with four players that unites network operators, information producers (who are IT product suppliers or IT security specialists; local information intermediaries and consumers of information. As a model of the information flow, a node can be selected that runs a local web portal that provides information to end users, generates new information, adapts information to the constraints of various distribution channels, and to the characteristics of end-user target groups. The methodology of the pilot project can be used in the design and deployment of a notification and information exchange system aimed at end-users of several regions or countries

Machine Vision System for Characterizing the Electric Field for the 225 Ra EDM Experiment

Science.gov (United States)

Sanchez, Andrew

2017-09-01

If an atom or fundamental particle possesses an electric dipole moment (EDM), that would imply time-reversal violation. At our current capability, if an EDM is detected in such a particle, that would suggest the discovery of beyond the standard model (BSM) physics. The unique structure of 225 Ra makes its atomic EDM favorable in the BSM search. An upgraded Ra-EDM apparatus will increase experimental sensitivity and the target electric field of 150 kV/cm will more than double the electric field used in previous experiments. To determine the electric field, the potential difference and electrode separation distance must be known. The optical method I have developed is a high-precision, non-invasive technique to measure electrode separation without making contact with the sensitive electrode surfaces. A digital camera utilizes a bi-telecentric lens to reduce parallax error and produce constant magnification throughout the optical system, regardless of object distance. A monochrome LED backlight enhances sharpness of the electrode profile, reducing uncertainty in edge determination and gap width. A program utilizing an edge detection algorithm allows precise, repeatable measurement of the gap width to within 1% and measurement of the relative angle of the electrodes. This work (SAM, Ra EDM) is supported by Michigan State University. This work (REU Program) is supported by U.S. National Science Foundation under Grant Number #1559866.

Assessing the reduction of the hydrological connectivity of gully systems through vegetation restoration: field experiments and numerical modelling

Directory of Open Access Journals (Sweden)

A. Molina

2009-10-01

well, as the error on the simulated total outflow volumes is below 13% for 15 out of 16 cases. However, predicting infiltration amounts is difficult: the high sensitivity of model results to some crucial hydraulic parameters (runoff width, hydraulic conductivity and sorptivity is one of the reasons why the relationships between model parameter values and gully features are relatively weak.

The results obtained from the field experiments show that gully systems are key elements in the hydrological connectivity of degraded landscapes. The transfer of overland flow and sediment from the slopes towards the river system highly depends on the presence/absence of vegetation in the gully beds and should therefore be accounted for in assessments of landscape degradation and/or recovery.

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.

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.)

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...

Toroidal field magnet and poloidal divertor field coil systems adapted to reactor requirements

International Nuclear Information System (INIS)

Koeppendoerfer, W.

1985-01-01

ASDEX Upgrade is a tokamak experiment with external poloidal field coils, that is now under construction at IPP Garching. It can produce elongated single-null (SN), double-null (DN) and limiter (L) configurations. The SN is the reference configuration with asymmetric load distributions in the poloidal field (PF) system and the toroidal field (TF) magnet. Plasma control and stabilization requires a rigid passive conductor close to the plasma. The design principles of the coils and support structure are described. (orig.)

Study of one dimensional magnetic system via field theory

International Nuclear Information System (INIS)

Talim, S.L.

1988-04-01

We present a study of one-dimensional magnetic system using field theory methods. We studied the discreteness effects in a classical anisotropic one dimensional antiferromagnet in an external magnetic field. It is shown that for TMMC, at the temperatures and magnetic fields where most experiments have been done, the corrections are small and can be neglected. (author)

Improvement of portable computed tomography system for on-field applications

Science.gov (United States)

Sukrod, K.; Khoonkamjorn, P.; Tippayakul, C.

2015-05-01

In 2010, Thailand Institute of Nuclear Technology (TINT) received a portable Computed Tomography (CT) system from the IAEA as part of the Regional Cooperative Agreement (RCA) program. This portable CT system has been used as the prototype for development of portable CT system intended for industrial applications since then. This paper discusses the improvements in the attempt to utilize the CT system for on-field applications. The system is foreseen to visualize the amount of agarwood in the live tree trunk. The experiments adopting Am-241 as the radiation source were conducted. The Am-241 source was selected since it emits low energy gamma which should better distinguish small density differences of wood types. Test specimens made of timbers with different densities were prepared and used in the experiments. The cross sectional views of the test specimens were obtained from the CT system using different scanning parameters. It is found from the experiments that the results are promising as the picture can clearly differentiate wood types according to their densities. Also, the optimum scanning parameters were determined from the experiments. The results from this work encourage the research team to advance into the next phase which is to experiment with the real tree on the field.

Improvement of Portable Computed Tomography System for On-field Applications

International Nuclear Information System (INIS)

Sukrod, K.; Khoonkamjorn, P.; Tippayakul, C.

2014-01-01

In 2010, Thailand Institute of Nuclear Technology (TINT) received a portable Computed Tomography (CT) system from IAEA as part of the Regional Cooperative Agreement (RCA) program. This portable CT system has been used as the prototype for development of portable CT system intended for industrial applications since then. This paper discusses the improvements in the attempt to utilize the CT system for on-field applications. The system is foreseen to visualize the amount of agarwood in the live tree trunk. The experiments adopting Am-241 as the radiation source were conducted. The Am-241 source was selected since it emits low energy gamma which should better distinguish small density differences of wood types. Test specimens made of timbers with different densities were prepared and used in the experiments. The cross sectional views of the test specimens were obtained from the CT system using different scanning parameters. It is found from the experiments that the results are promising as the picture can clearly differentiate wood types according to their densities. Also, the optimum scanning parameters were determined from the experiments. The results from this work encourage the research team to advance into the next phase which is to experiment with the real tree on the field.

Improvement of portable computed tomography system for on-field applications

International Nuclear Information System (INIS)

Sukrod, K; Khoonkamjorn, P; Tippayakul, C

2015-01-01

In 2010, Thailand Institute of Nuclear Technology (TINT) received a portable Computed Tomography (CT) system from the IAEA as part of the Regional Cooperative Agreement (RCA) program. This portable CT system has been used as the prototype for development of portable CT system intended for industrial applications since then. This paper discusses the improvements in the attempt to utilize the CT system for on-field applications. The system is foreseen to visualize the amount of agarwood in the live tree trunk. The experiments adopting Am-241 as the radiation source were conducted. The Am-241 source was selected since it emits low energy gamma which should better distinguish small density differences of wood types. Test specimens made of timbers with different densities were prepared and used in the experiments. The cross sectional views of the test specimens were obtained from the CT system using different scanning parameters. It is found from the experiments that the results are promising as the picture can clearly differentiate wood types according to their densities. Also, the optimum scanning parameters were determined from the experiments. The results from this work encourage the research team to advance into the next phase which is to experiment with the real tree on the field. (paper)

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.

Experiments on the flow field physics of confluent boundary layers for high-lift systems

Science.gov (United States)

Nelson, Robert C.; Thomas, F. O.; Chu, H. C.

1994-01-01

The use of sub-scale wind tunnel test data to predict the behavior of commercial transport high lift systems at in-flight Reynolds number is limited by the so-called 'inverse Reynolds number effect'. This involves an actual deterioration in the performance of a high lift device with increasing Reynolds number. A lack of understanding of the relevant flow field physics associated with numerous complicated viscous flow interactions that characterize flow over high-lift devices prohibits computational fluid dynamics from addressing Reynolds number effects. Clearly there is a need for research that has as its objective the clarification of the fundamental flow field physics associated with viscous effects in high lift systems. In this investigation, a detailed experimental investigation is being performed to study the interaction between the slat wake and the boundary layer on the primary airfoil which is known as a confluent boundary layer. This little-studied aspect of the multi-element airfoil problem deserves special attention due to its importance in the lift augmentation process. The goal of this research is is to provide an improved understanding of the flow physics associated with high lift generation. This process report will discuss the status of the research being conducted at the Hessert Center for Aerospace Research at the University of Notre Dame. The research is sponsored by NASA Ames Research Center under NASA grant NAG2-905. The report will include a discussion of the models that have been built or that are under construction, a description of the planned experiments, a description of a flow visualization apparatus that has been developed for generating colored smoke for confluent boundary layer studies and some preliminary measurements made using our new 3-component fiber optic LDV system.

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.

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

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.

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

Preserving experience through expert systems

International Nuclear Information System (INIS)

Jelinek, J.B.; Weidman, S.H.

1989-01-01

Expert systems technology, one of the branches in the field of computerized artificial intelligence, has existed for >30 yr but only recently has been made available on commercially standard hardware and software platforms. An expert system can be defined as any method of encoding knowledge by representing that knowledge as a collection of facts or objects. Decisions are made by the expert program by obtaining data about the problem or situation and correlating encoded facts (knowledge) to the data until a conclusion can be reached. Such conclusions can be relayed to the end user as expert advice. Realizing the potential of this technology, General Electric (GE) Nuclear Energy (GENE) has initiated a development program in expert systems applications; this technology offers the potential for packaging, distributing, and preserving nuclear experience in a software form. The paper discusses application fields, effective applications, and knowledge acquisition and knowledge verification

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...

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

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)

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

A field experiment of energy education using integrative learning support system

International Nuclear Information System (INIS)

Obayashi, Fumiaki; Yamamoto, Atsumu; Ito, Kyoko; Shimoda, Hiroshi; Yoshikawa, Hidekazu

2002-01-01

A new energy learning support system for higher education was the object of this experiment. The aim of this learning support system is to support students within an integrative study environment in which various personal skills and general knowledge on energy related issues are to be developed. The main goals of this learning tool for the students are to simulate their interest and creativity, to enhance awareness, to increase capability of researching on the subject and to improve problem-solving skills on energy related issues. The salient feature of this learning support system is that it is used for group learning by which each learner can develop the ability to reflect on the subject through mutual discussion. Moreover, in order to keep the attention of the students on the topic and provide them with a better assimilation of the curriculum, a personified agent is used as a cooperative associate who assists learners through natural communication, using voice conversation function in Japanese language. Then, the subject experiment has been conducted. Also, means of effective energy education are discussed in this research. As a conclusion, this learning support system is proven to be effective and the use of it for energy education is recommended. (author)

The Romanian educational system in nuclear engineering field - experience and new approaches

International Nuclear Information System (INIS)

Dragusin, O.; Burghelea, A.

2001-01-01

In this paper we would like to present the actual status of the education in the nuclear engineering field at 'Pantholic' University Bucharest, Romania, Power Engineering Faculty, Nuclear Power Plant Department, and also the efforts of integration of the educational system of Romania into the international system and the development of new concepts concerning the education of the new specialists generation. (authors)

Magnet system studies for the Zeus experiment

International Nuclear Information System (INIS)

Baynham, D.E.; Coombs, R.C.; Uden, C.N.

1985-11-01

The ZEUS experiment will be mounted at the HERA accelerator complex currently under construction at DESY, Hamburg. A large volume of magnetic field will be required for charge selection of particles and track fitting. Two superconducting magnet systems which meet the parameters of the ZEUS Experiment are described; a small solenoid with good radiation transparency and a large aperture Helmholtz coil configuration. Basic design concepts and parameters are presented. (author)

Malware Forensics Field Guide for Windows Systems Digital Forensics Field Guides

CERN Document Server

Malin, Cameron H; Aquilina, James M

2010-01-01

Dissecting the dark side of the Internet with its infectious worms, botnets, rootkits, and Trojan horse programs (known as malware) is a treaterous condition for any forensic investigator or analyst. Written by information security experts with real-world investigative experience, Malware Forensics Field Guide for Windows Systems is a "tool" with checklists for specific tasks, case studies of difficult situations, and expert analyst tips. *A condensed hand-held guide complete with on-the-job tasks and checklists *Specific for Windows-based systems, the largest running OS in the world

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.

Tokamak Fusion Core Experiment (TFCX) special-purpose remote maintenance systems

International Nuclear Information System (INIS)

Masson, L.S.; Welland, H.J.

1985-01-01

A key element in the preconceptual design of the Tokamak Fusion Core Experiment (TFCX) was the development of design concepts for special-purpose remote maintenance systems. Included were systems for shield sector replacement, vacuum vessel sector and toroidal field coil replacement, limiter blade replacement, protective tile replacement, and general-purpose maintenance. This paper addresses these systems as they apply to the copper toroidal field (TF) coil version of the TFCX

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).

Leveling the field: The role of training, safety programs, and knowledge management systems in fostering inclusive field settings

Science.gov (United States)

Starkweather, S.; Crain, R.; Derry, K. R.

2017-12-01

Knowledge is empowering in all settings, but plays an elevated role in empowering under-represented groups in field research. Field research, particularly polar field research, has deep roots in masculinized and colonial traditions, which can lead to high barriers for women and minorities (e.g. Carey et al., 2016). While recruitment of underrepresented groups into polar field research has improved through the efforts of organizations like the Association of Polar Early Career Scientists (APECS), the experiences and successes of these participants is often contingent on the availability of specialized training opportunities or the quality of explicitly documented information about how to survive Arctic conditions or how to establish successful measurement protocols in harsh environments. In Arctic field research, knowledge is often not explicitly documented or conveyed, but learned through "experience" or informally through ad hoc advice. The advancement of field training programs and knowledge management systems suggest two means for unleashing more explicit forms of knowledge about field work. Examples will be presented along with a case for how they level the playing field and improve the experience of field work for all participants.

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

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...

Overview of long-term field experiments in Germany - metadata visualization

Science.gov (United States)

Muqit Zoarder, Md Abdul; Heinrich, Uwe; Svoboda, Nikolai; Grosse, Meike; Hierold, Wilfried

2017-04-01

BonaRes ("soil as a sustainable resource for the bioeconomy") is conducting to collect data and metadata of agricultural long-term field experiments (LTFE) of Germany. It is funded by the German Federal Ministry of Education and Research (BMBF) under the umbrella of the National Research Strategy BioEconomy 2030. BonaRes consists of ten interdisciplinary research project consortia and the 'BonaRes - Centre for Soil Research'. BonaRes Data Centre is responsible for collecting all LTFE data and regarding metadata into an enterprise database upon higher level of security and visualization of the data and metadata through data portal. In the frame of the BonaRes project, we are compiling an overview of long-term field experiments in Germany that is based on a literature review, the results of the online survey and direct contacts with LTFE operators. Information about research topic, contact person, website, experiment setup and analyzed parameters are collected. Based on the collected LTFE data, an enterprise geodatabase is developed and a GIS-based web-information system about LTFE in Germany is also settled. Various aspects of the LTFE, like experiment type, land-use type, agricultural category and duration of experiment, are presented in thematic maps. This information system is dynamically linked to the database, which means changes in the data directly affect the presentation. An easy data searching option using LTFE name, -location or -operators and the dynamic layer selection ensure a user-friendly web application. Dispersion and visualization of the overlapping LTFE points on the overview map are also challenging and we make it automatized at very zoom level which is also a consistent part of this application. The application provides both, spatial location and meta-information of LTFEs, which is backed-up by an enterprise geodatabase, GIS server for hosting map services and Java script API for web application development.

TPX Poloidal Field (PF) power systems simulation

International Nuclear Information System (INIS)

Lu, E.; Bronner, G.

1993-01-01

This paper describes the modeling and simulation of the PF power system for the Tokamak Physics Experiment (TPX), which is required to supply pulsed DC current to the Poloidal Field (PF) superconducting coil system. An analytical model was developed to simulate the dynamics of the PF power system for any PF current scenario and thereby provide the basis for selection of PF circuit topology, in support of the major design goal of optimizing the use of the existing Tokamak Fusion Test Reactor (TFTR) facilities at the Princeton Plasma Physics Lab (PPPL)

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

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)

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

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,…

The ASDEX upgrade toroidal field magnet and poloidal divertor field coil system adapted to reactor requirements

International Nuclear Information System (INIS)

Koeppendoerfer, W.; Blaumoser, M.; Ennen, K.; Gruber, J.; Gruber, O.; Jandl, O.; Kaufmann, M.; Kollotzek, H.; Kotzlowski, H.; Lackner, E.; Lackner, K.; Larcher, T. von; Noterdaeme, J.M.; Pillsticker, M.; Poehlchen, R.; Preis, H.; Schneider, H.; Seidel, U.; Sombach, B.; Speth, E.; Streibl, B.; Vernickel, H.; Werner, F.; Wesner, F.; Wieczorek, A.

1986-01-01

ASDEX Upgrade is a tokamak experiment with external poloidal field coils that is now under construction at IPP Garching. It can produce elongated single-null (SN), double-null (DN) , and limiter (L) configurations. The SN is the reference configuration with asymmetric load distributions in the poloidal field (PF) system and the toroidal field (TF) magnet. Plasma control and stabilization require a rigid passive conductor close to the plasma. The design principles of the coils and support structure are described. (orig.)

IFSS: The IAEA's inspection field support system

International Nuclear Information System (INIS)

Muller, R.; Heinonen, O.J.; Schriefer, D.

1990-01-01

Recently, highly automated nuclear facilities with enormous volumes of nuclear material accounting data have come into operation. A few others will become operational shortly. Analysis and verification of the data for safeguards purposes is manageable only with improved computer support in the field. To assist its safeguards inspectors, the IAEA has developed the Inspection Field Support System (IFSS). It allows safeguards inspectors to collect, maintain, analyse, and evaluate inspection data on site at nuclear facilities. Previously, field computer support to safeguards inspectors concentrated on providing measurement instrumentation with data storage, but data analysis capabilities were elementary. Also, generic statistical tools were available to handle data that inspectors could (usually manually) input into a computer. Electronic links between these two directions were rudimentary. IFSS integrates the data required for verification and accounting so that inspectors will be able to devote more time to measurements and to derive conclusions at the site in a more timely manner. The system operates on stationary personal computers as well as on portable ones. Its introduction reflects the IAEA Department of Safeguards determination to further improve operational efficiency. It should be emphasized that IFSS implementation is still under development. Several field installations have been made to obtain practical experience and to determine the system's effectiveness

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

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

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....

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

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…

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

Near-field optical recording based on solid immersion lens system

Science.gov (United States)

Hong, Tao; Wang, Jia; Wu, Yan; Li, Dacheng

2002-09-01

Near-field optical recording based on solid immersion lens (SIL) system has attracted great attention in the field of high-density data storage in recent years. The diffraction limited spot size in optical recording and lithography can be decreased by utilizing the SIL. The SIL near-field optical storage has advantages of high density, mass storage capacity and compatibility with many technologies well developed. We have set up a SIL near-field static recording system. The recording medium is placed on a 3-D scanning stage with the scanning range of 70×70×70μm and positioning accuracy of sub-nanometer, which will ensure the rigorous separation control in SIL system and the precision motion of the recording medium. The SIL is mounted on an inverted microscope. The focusing between long working distance objective and SIL can be monitored and observed by the CCD camera and eyes. Readout signal can be collected by a detector. Some experiments have been performed based on the SIL near-field recording system. The attempt of the near-field recording on photochromic medium has been made and the resolution improvement of the SIL has been presented. The influence factors in SIL near-field recording system are also discussed in the paper.

Laboratory experiments on plasma jets in a magnetic field using high-power lasers

Directory of Open Access Journals (Sweden)

Nishio K.

2013-11-01

Full Text Available The experiments to simulate astrophysical jet generation are performed using Gekko XII (GXII HIPER laser system at the Institute of Laser Engineering. In the experiments a fast plasma flow generated by shooting a CH plane (10 μm thickness is observed at the rear side of the plane. By separating the focal spot of the main beams, a non-uniform plasma is generated. The non-uniform plasma flow in an external magnetic field (0.2∼0.3 T perpendicular to the plasma is more collimated than that without the external magnetic field. The plasma β, the ratio between the plasma and magnetic pressure, is ≫ 1, and the magnetic Reynolds number is ∼150 in the collimated plasma. It is considered that the magnetic field is distorted by the plasma flow and enhances the jet collimation.

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

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

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,

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.)

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

Self-generated magnetic fields in direct-drive implosion experiments

Energy Technology Data Exchange (ETDEWEB)

Igumenshchev, I. V.; Nilson, P. M.; Goncharov, V. N. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623 (United States); Zylstra, A. B.; Li, C. K.; Petrasso, R. D. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2014-06-15

Electric and self-generated magnetic fields in direct-drive implosion experiments on the OMEGA Laser Facility were investigated employing radiography with ∼10- to 60-MeV protons. The experiment used plastic-shell targets with imposed surface defects (glue spots, wires, and mount stalks), which enhance self-generated fields. The fields were measured during the 1-ns laser drive with an on-target intensity ∼10{sup 15} W/cm{sup 2}. Proton radiographs show multiple ring-like structures produced by electric fields ∼10{sup 7} V/cm and fine structures from surface defects, indicating self-generated fields up to ∼3 MG. These electric and magnetic fields show good agreement with two-dimensional magnetohydrodynamic simulations when the latter include the ∇T{sub e} × ∇n{sub e} source, Nernst convection, and anisotropic resistivity. The simulations predict that self-generated fields affect heat fluxes in the conduction zone and, through this, affect the growth of local perturbations.

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…

Toward the Experimental Characterization of an Unmanned Air System Flow Field

Science.gov (United States)

Velarde, John-Michael; Connors, Jacob; Glauser, Mark

2017-11-01

The velocity flow field around a small unmanned air system (sUAS) is investigated in a series of experiments at Syracuse University. Experiments are conducted in the 2'x2' sub-sonic wind tunnel at Syracuse University and the Indoor Flow Lab. The goal of these experiments is to gain a better understanding of the rich, turbulent flow field that a sUAS creates. Comparison to large, multi-rotor manned vehicles is done to gain a better understanding of the flow physics that could be occurring with the sUAS. Regions of investigation include the downwash, above the vehicle, and far downstream. Characterization of the flow is performed using hotwire anemometry. Investigation of several locations around the sUAS show that dominant frequencies exist within the flow field. Analysis of the flow field using power spectral density will be presented as well as looking at which parameters have an effect on these dominant frequencies.

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

Are particle rest masses variable: Theory and constraints from solar system experiments

International Nuclear Information System (INIS)

Bekenstein, J.D.

1977-01-01

Particle rest mass variation in spacetime is considered. According to Dicke, if this is the case various null experiments indicate that all masses vary in the same way. Their variation relative to the Planck-Wheeler mass defines a universal scalar rest-mass field. We construct the relativistic dynamics for this field based on very general assumptions. In addition, we assume Einstein's equations to be valid in Planck-Wheeler units. A special case of the theory coincides with Dicke's reformulation of Brans-Dicke theory as general relativity with variable rest masses. In the general case the rest-mass field is some power r of a scalar field which obeys an ordinary scalar equation with coupling to the curvature of strength q. The r and q are the only parameters of the theory. Comparison with experiment is facilitated by recasting the theory into units in which rest masses are constant, the Planck-Wheeler mass varies, and the metric satisfies the equations of a small subset of the scalar-tensor theories of gravitation. The results of solar system experiments, usually used to test general relativity, are here used to delimit the acceptable values of r and q. We conclude that if cosmological considerations are not invoked, then the solar system experiments do not rule out the possibility of rest-mass variability. That is, there are theories which agree with all null and solar system experiments, and yet contradict the strong equivalence principle by allowing rest masses to vary relative to the Planck-Wheeler mass. We show that the field theory of the rest-mass field can be quantized and interpreted in terms of massless scalar quanta which interact very weakly with matter. This explains why they have not turned up in high-energy experiments. In future reports we shall investigate the implications of various cosmological and astrophysical data for the theory of variable rest masses. The ultimate goal is a firm decision on whether rest masses vary or not

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.

Field experience and performance evaluation of a medium-concentration CPV system

Science.gov (United States)

Norton, Matthew; Bentley, Roger; Georghiou, George E.; Chonavel, Sylvain; De Mutiis, Alfredo

2012-10-01

With the aim of gaining experience and performance data from location with a harsh summer climate, a 70 X concentrating photovoltaic (CPV) system was installed in Janurary 2009 in Nicosia, Cyprus. The performance of this system has been monitored using regular current-voltage characterisations for three years. Over this period, the output of the system has remained fairly constant. Measured performance ratios varied from 0.79 to 0.86 in the winter, but fell to 0.64 over the year when left uncleaned. Operating cell temperatures were modeled and found to be similar to those of flat plate modules. The most significant causes of energy loss have been identified as originating from tracking issues and soiling. Losses due to soiling could account for a drop in output of 0.2% per day. When cleaned and properly oriented, the normalized output of the system has remained constant, suggesting that this particular design is tolerant to the physical strain of long-term outdoor exposure in harsh summer conditions. Regular cleaning and reliable tracker operation are shown to be essential for maximizing energy yield.

Time delay systems theory, numerics, applications, and experiments

CERN Document Server

Ersal, Tulga; Orosz, Gábor

2017-01-01

This volume collects contributions related to selected presentations from the 12th IFAC Workshop on Time Delay Systems, Ann Arbor, June 28-30, 2015. The included papers present novel techniques and new results of delayed dynamical systems. The topical spectrum covers control theory, numerical analysis, engineering and biological applications as well as experiments and case studies. The target audience primarily comprises research experts in the field of time delay systems, but the book may also be beneficial for graduate students alike. .

DC electrostatic gyro suspension system for the Gravity Probe B experiment

Science.gov (United States)

Wu, Chang-Huei

1994-12-01

The Gravity Probe B experiment is a satellite-based experiment primarily designed to test two aspects of Einstein's General Theory of Relativity by observing the spin axis drift of near-perfect gyroscopes in a 650-km circular polar orbit. The goal of this experiment is to measure the drift angles to an accuracy of 0.3 milli-arcsec after one year in orbit. As a result, electrostatically suspended free-spinning gyroscopes operating at a very low temperature became the final choice for their ultra-low Newtonian torque-induced drift rate. The Conventional AC current-driven suspension system faces two fundamental difficulties for ground gyro testing. Field emission causes rotor charging and arcing with an imperfect electrode or rotor surfaces because the electric field intensity needed to support a solid rotor in the 1-g field is more than 107 V/m. The system not only becomes unstable at a high rotor charge, which can be more than 500 volts, but may also lose control in case of arcing. Both the high voltage AC suspension signal and the high frequency (1 MHz) signal for rotor position sensing interfere with the superconducting SQUID magnetometer for spin axis readout through inductive coupling. These problems were resolved by using DC voltage to generate a suspension force and a low frequency position sensor. In addition to the Input/Output linearization algorithm developed to remove the system nonlinearity for global stability and dynamic performance, we also minimized the electric field intensity to reduce rotor charging. Experimental results verified the desired global stability and satisfactory dynamic performance. The problem of rotor charging is virtually eliminated. More importantly, the DC system is compatible with the SQUID readout system in the Science Mission configuration. Consequently, experiments in low magnetic field at a sub-micro-gauss level for SQUID design verification and trapped flux distribution study were finally realizable in ground environment

Herding agent field application system development

Energy Technology Data Exchange (ETDEWEB)

Buist, Ian; Belore, Randy [SL Ross Environmental Research (Canada)], email: ian@slross.com

2011-07-01

Chemical herding agents can be applied to deal with an oil slick. This study investigates the key system components of application systems for herding agents and shows how application systems can also be developed for operational herder usage in drift ice. These two application systems are respectively required for small boat and a helicopter operations. The factors, including the selection of flow rates, pressures and atomizing nozzle types, which give the appropriate herder droplet size distributions for small boat and aerial application systems were investigated in the initial stage of the study. In a later stage, on commercializing herders for in situ burning, further research is expected to deal with the many problems not tackled in the initial stage, such as the mounting of the nozzles, pumps and reservoirs on various aerial platforms and the provision of heating and insulation for cold-weather use. The paper presented the experiments and simulations that have been conducted as well as the basic design parameters for field application systems.

The superconducting magnet system for the Tokamak Physics Experiment

International Nuclear Information System (INIS)

Lang, D.D.; Bulmer, R.J.; Chaplin, M.R.; O'Connor, T.G.; Slack, D.S.; Wong, R.L.; Zbasnik, J.P.; Schultz, J.H.; Diatchenko, N.; Montgomery, D.B.

1994-01-01

The superconducting magnet system for the Tokamak Physics eXperiment (TPX) will be the first all superconducting magnet system for a Tokamak, where the poloidal field coils, in addition to the toroidal field coils are superconducting. The magnet system is designed to operate in a steady state mode, and to initiate the plasma discharge ohmically. The toroidal field system provides a peak field of 4.0 Tesla on the plasma axis at a plasma major radius of 2.25 m. The peak field on the niobium 3-tin, cable-in-conduit (CIC) conductor is 8.4 Tesla for the 16 toroidal field coils. The toroidal field coils must absorb approximately 5 kW due to nuclear heating, eddy currents, and other sources. The poloidal field system provides a total of 18 volt seconds to initiate the plasma and drive a plasma current up to 2 MA. The poloidal field system consists of 14 individual coils which are arranged symmetrically above and below the horizontal mid plane. Four pairs of coils make up the central solenoid, and three pairs of poloidal ring coils complete the system. The poloidal field coils all use a cable-in-conduit conductor, using either niobium 3-tin (Nb 3 Sn) or niobium titanium (NbTi) superconducting strands depending on the operating conditions for that coil. All of the coils are cooled by flowing supercritical helium, with inlet and outlet connections made on each double pancake. The superconducting magnet system has gone through a conceptual design review, and is in preliminary design started by the LLNL/MIT/PPPL collaboration. A number of changes have been made in the design since the conceptual design review, and are described in this paper. The majority of the design and all fabrication of the superconducting magnet system will be ,accomplished by industry, which will shortly be taking over the preliminary design. The magnet system is expected to be completed in early 2000

Research on the novel FBG detection system for temperature and strain field distribution

Science.gov (United States)

Liu, Zhi-chao; Yang, Jin-hua

2017-10-01

In order to collect the information of temperature and strain field distribution information, the novel FBG detection system was designed. The system applied linear chirped FBG structure for large bandwidth. The structure of novel FBG cover was designed as a linear change in thickness, in order to have a different response at different locations. It can obtain the temperature and strain field distribution information by reflection spectrum simultaneously. The structure of novel FBG cover was designed, and its theoretical function is calculated. Its solution is derived for strain field distribution. By simulation analysis the change trend of temperature and strain field distribution were analyzed in the conditions of different strain strength and action position, the strain field distribution can be resolved. The FOB100 series equipment was used to test the temperature in experiment, and The JSM-A10 series equipment was used to test the strain field distribution in experiment. The average error of experimental results was better than 1.1% for temperature, and the average error of experimental results was better than 1.3% for strain. There were individual errors when the strain was small in test data. It is feasibility by theoretical analysis, simulation calculation and experiment, and it is very suitable for application practice.

The transient electric field measurement system for EAST device

Energy Technology Data Exchange (ETDEWEB)

Wang, Y., E-mail: wayong@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui (China); Ji, Z.S. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui (China); Zhu, C.M. [The Experiment & Verification Center of State Grid Electric Power Research Institute (The Automation Equipment EMC Lab. of State Grid Co.), Nanjing, Jiangsu (China); Zhang, Z.C.; Ma, T.F.; Xu, Z.H. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui (China)

2016-11-15

The electromagnetic environment around the Experimental Advanced Superconducting Tokamak (EAST) device is very complex during plasma discharge experiment. In order to fully monitor the changes of electric field around the EAST device during plasma discharge, a transient electric field measurement system based on PCI eXtensions for Instrumentation (PXI) platform has been designed. A digitizer is used for high-speed data acquisition of raw signals from electric field sensors, and a Field Programmable Gate Array (FPGA) module is used for realizing an on-the-fly fast Fourier transform (FFT) and inverse fast Fourier transform (IFFT) algorithm including a beforehand identified antenna factor (AF) to achieve finally a calibrated and filtered electric field measurement, then these signals can be displayed and easily analyzed. The raw signals from electric field sensors are transferred through optical fiber by optical isolation to reduce electromagnetic interference (EMI). The high speed data streaming technology is used for data storage. A prototype of this system has been realized to measure the transient electric field strength, with the real-time processing and continuous acquisition ability of one channel of 14-bit resolution and up to 50 MHz sampling rate, and 6 KHz FFT frequency resolution.

Integrated management systems in the nuclear field

International Nuclear Information System (INIS)

Beckmerhagen, I.A.; Berg, H.P.; Karapetrovic, S.V.; Willborn, W.O.

2005-01-01

In the last years several internationally accepted standards such as the ISO 9000 and ISO 14000 series and other function-specific management systems standards have been developed. At the same time, it has become imperative for organisations to continuously improve their overall quality, environmental and safety performance. Therefore, the need to create integrated management systems is of growing importance to enable an easier handling of the different management systems. This paper has two main objectives. The first one is to address the key issues in the underlying theory of integrated management systems including benefits and limits, the second one is to illustrate the importance of an integrated (in particular safety) management system and the experience feedback providing examples from different areas and different organisations in the nuclear field. (orig.)

Particle Based Modeling of Electrical Field Flow Fractionation Systems

Directory of Open Access Journals (Sweden)

Tonguc O. Tasci

2015-10-01

Full Text Available Electrical Field Flow Fractionation (ElFFF is a sub method in the field flow fractionation (FFF family that relies on an applied voltage on the channel walls to effect a separation. ElFFF has fallen behind some of the other FFF methods because of the optimization complexity of its experimental parameters. To enable better optimization, a particle based model of the ElFFF systems has been developed and is presented in this work that allows the optimization of the main separation parameters, such as electric field magnitude, frequency, duty cycle, offset, flow rate and channel dimensions. The developed code allows visualization of individual particles inside the separation channel, generation of realistic fractograms, and observation of the effects of the various parameters on the behavior of the particle cloud. ElFFF fractograms have been generated via simulations and compared with experiments for both normal and cyclical ElFFF. The particle visualizations have been used to verify that high duty cycle voltages are essential to achieve long retention times and high resolution separations. Furthermore, by simulating the particle motions at the channel outlet, it has been demonstrated that the top channel wall should be selected as the accumulation wall for cyclical ElFFF to reduce band broadening and achieve high efficiency separations. While the generated particle based model is a powerful tool to estimate the outcomes of the ElFFF experiments and visualize particle motions, it can also be used to design systems with new geometries which may lead to the design of higher efficiency ElFFF systems. Furthermore, this model can be extended to other FFF techniques by replacing the electrical field component of the model with the fields used in the other FFF techniques.

Urban Field Experiences for Undergraduate Liberal Arts Students: Using Compromised Environments as Living Laboratories

Science.gov (United States)

MacAvoy, S. E.; Knee, K.

2015-12-01

While urban environments may lack the beauty of relatively pristine field sites, they can be used to deliver an effective demonstration of actual environmental damage. Students demanding applied field experiences from their undergraduate environmental science programs can be well served in urban settings. Here, we present strategies for integrating degraded urban systems into the undergraduate field experience. 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. Students spend labs immersed in streams and wetlands heavily impacted by the urban runoff their city generates. Here we share 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.

Contributing to Sustainability Education of East Asian University Students through a Field Trip Experience: A Social-Ecological Perspective

Directory of Open Access Journals (Sweden)

Tae Kyung Yoon

2016-10-01

Full Text Available This study reports the effects of a field trip environmental education program with a social-ecological perspective on the experience and learning of university students from China, Japan, South Korea and Vietnam. The students visited Jeju Island, the Saemangeum Sea Dike, the Demilitarized Zone and Seoul, South Korea. Their experiences and learning about social-ecological interactions were analyzed using the new environmental paradigm test, an evaluation questionnaire, group presentations and individual reports. Across demographic characteristics, the participants believed the program fairly presented the concept of social-ecological systems. Some developed new ideas of social-ecological systems through interpreting, transforming and contextualizing their field trip experience based on prior knowledge bases; others compared the sites to case studies. They preferred the sites where social-ecological issues were clearly presented by well-preserved landscapes, successful environmental management or environmental conflict. The results show the need for an advanced multi-dimensional methodology to evaluate students’ learning through constructive processes. The program design of this study from planning to field trip and evaluation, the field site design in which regional site resources were organized in a social-ecological context and the analysis of participants’ learning and experiences could contribute to attempts to couple the social-ecological perspective with the practice of sustainability and environmental education in field trip design.

A Dual-Field Sensing Scheme for a Guidance System for the Blind

Directory of Open Access Journals (Sweden)

Qing Lin

2016-05-01

Full Text Available An electronic guidance system is very helpful in improving blind people’s perceptions in a local environment. In our previous work “Lin, Q.; Han, Y. A Context-Aware-Based Audio Guidance System for Blind People Using a Multimodal Profile Model. Sensors 2014, 14, 18670–18700”, a context-aware guidance system using a combination of a laser scanner and a camera was proposed. By using a near-field graphical model, the proposed system could interpret a near-field scene in very high resolution. In this paper, our work is extended by adding a far-field graphical model. The integration of the near-field and the far-field models constitutes a dual-field sensing scheme. In the near-field range, reliable inference of the ground and object status is obtained by fusing range data and image data using the near-field graphical model. In the far-field range, which only the camera can cover, the far-field graphical model is proposed to interpret far-field image data based on appearance and spatial prototypes built using the near-field interpreted data. The dual-field sensing scheme provides a solution for the guidance systems to optimise their scene interpretation capability using simple sensor configurations. Experiments under various local conditions were conducted to show the efficiency of the proposed scheme in improving blind people’s perceptions in urban environments.

Study on the system development for evaluating long-term alteration of hydraulic field in near field

International Nuclear Information System (INIS)

Okutu, Kazuo; Morikawa, Seiji; Takamura, Hisashi

2002-02-01

For the high performance evaluation of reliability of TRU waste repository, the system development for evaluating long-term alteration in consideration of the changes action of barrier materials of hydraulic field in Near Field is required. In this research, system development for evaluating long-term alteration of hydraulic field in Near Field was examined. Examination of the basic specification of chemical/dynamic alteration action analysis system used as the composition element of this system and a whole system were performed. The research result of this year is shown below. 1) The system by which the chemical changes happened by Near Field as influence of the exudation liquid from cement material are evaluated was examined. In this year, document investigation about the various processes about chemical alteration and extraction of a choice, presentation of the uncertainty about a model or data, preliminary modeling, a simple analysis tool creation and sensitivity analysis, extraction of the process which should be taken into consideration in a system valuation modeling and a phenomenon analysis model, and a corresponding mathematics model, optimization of the software composition for development of a system valuation modeling, the exercise by the preliminary system analysis model, the experiment plan for the corroboration of a model were shown. 2) In consideration of change of the physical characteristic accompanying chemical alteration of bentonite material and cement material, the system by which dynamic changes action of repository is evaluated was examined. In this year, arrangement of the dynamics action of repository for long-term were shown. Extraction of a phenomenon made applicable to evaluation was shown. And the dynamic models were investigated and the prototype of the dynamics model that can take into consideration the characteristic of bentonite material was shown. And the basic composition of a dynamic changes action analysis system was shown. 3

Development of field navigation system; Field navigation system no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Ibara, S; Minode, M; Nishioka, K [Daihatsu Motor Co. Ltd., Osaka (Japan)

1995-04-20

This paper describes the following matters on a field navigation system developed for the purpose of covering a field of several kilometer square. This system consists of a center system and a vehicle system, and the center system comprises a map information computer and a communication data controlling computer; since the accuracy for a vehicle position detected by a GPS is not sufficient, an attempt of increasing the accuracy of vehicle position detection is made by means of a hybrid system; the hybrid system uses a satellite navigation method of differential system in which the error components in the GPS are transmitted from the center, and also uses a self-contained navigation method which performs an auxiliary function when the accuracy in the GPS has dropped; corrected GPS values, emergency messages to all of the vehicles and data of each vehicle position are communicated by wireless transmission in two ways between the center and vehicles; and accommodation of the map data adopted a system that can respond quickly to any change in roads and facilities. 3 refs., 13 figs., 1 tab.

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)

Science objectives of the magnetic field experiment onboard Aditya-L1 spacecraft

Science.gov (United States)

Yadav, Vipin K.; Srivastava, Nandita; Ghosh, S. S.; Srikar, P. T.; Subhalakshmi, Krishnamoorthy

2018-01-01

The Aditya-L1 is first Indian solar mission scheduled to be placed in a halo orbit around the first Lagrangian point (L1) of Sun-Earth system in the year 2018-19. The approved scientific payloads onboard Aditya-L1 spacecraft includes a Fluxgate Digital Magnetometer (FGM) to measure the local magnetic field which is necessary to supplement the outcome of other scientific experiments onboard. The in-situ vector magnetic field data at L1 is essential for better understanding of the data provided by the particle and plasma analysis experiments, onboard Aditya-L1 mission. Also, the dynamics of Coronal Mass Ejections (CMEs) can be better understood with the help of in-situ magnetic field data at the L1 point region. This data will also serve as crucial input for the short lead-time space weather forecasting models. The proposed FGM is a dual range magnetic sensor on a 6 m long boom mounted on the Sun viewing panel deck and configured to deploy along the negative roll direction of the spacecraft. Two sets of sensors (tri-axial each) are proposed to be mounted, one at the tip of boom (6 m from the spacecraft) and other, midway (3 m from the spacecraft). The main science objective of this experiment is to measure the magnitude and nature of the interplanetary magnetic field (IMF) locally and to study the disturbed magnetic conditions and extreme solar events by detecting the CME from Sun as a transient event. The proposed secondary science objectives are to study the impact of interplanetary structures and shock solar wind interaction on geo-space environment and to detect low frequency plasma waves emanating from the solar corona at L1 point. This will provide a better understanding on how the Sun affects interplanetary space. In this paper, we shall give the main scientific objectives of the magnetic field experiment and brief technical details of the FGM onboard Aditya-1 spacecraft.

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

Perturbing an electromagnetically induced transparency in a Λ system using a low-frequency driving field. II. Four-level system

International Nuclear Information System (INIS)

Wilson, E. A.; Manson, N. B.; Wei, C.

2005-01-01

The effect a perturbing field has on an electromagnetically induced transparency within a three-level Λ system is presented. The perturbing field is applied resonant between one of the lower levels of the Λ system and a fourth level. The electromagnetically induced transparency feature is split and this is measured experimentally for both single and bichromatic driving fields. In the single-driving-field case a density matrix treatment is shown to be in reasonable agreement with experiment and in both single and bichromatic cases the structure in the spectrum can be explained using a dressed-state analysis

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.

Perspectives of expert systems in the field of reactor safety

International Nuclear Information System (INIS)

Bastl, W.

1989-01-01

The furure potential of expert systems is based on the following factors: the efficient storage of information in the knowledge basis, the efficient use of comprehensive information bases, the interactive approach, the rapid production of prototypes. The main problems which are encountered at present relate to the input of knowledge derived from experience, the qualification of the contents of the knowledge bases and to the interfacing to technical processes, as real time work is required in such cases. However, the practical use of expert systems in reactor safety is expected to make considerable progress. The following preferred fields should be mentioned: knowledge bases and analysis tools for safety investigations, diagnostic and practising systems for safe operation and, above all in the field of accident management, trainers, in-situ guiding systems or information systems in supraregional guiding centers. (orig./DG) [de

Comparison of different soil water extraction systems for the prognoses of solute transport at the field scale using numerical simulations, field and lysimeter experiments

Energy Technology Data Exchange (ETDEWEB)

Weihermueller, L

2005-07-01

To date, the understanding of processes, factors, and interactions that influence the amount of extracted water and the solute composition sampled with suction cups is limited. But this information is required for process description of solute transport in natural soils. Improved system understanding can lead to a low cost and easy to install water sampling system which can help to predict solute transport in natural soils for the benefit of environmental protection. The main objectives of this work were to perform numerical simulations with different boundary conditions and to implement the findings in the interpretation of the lysimeter and field experiments. In a first part of this thesis, theoretical considerations on the processes affecting the spatial influence of a suction cup in soil and changes in solute transport initiated by the suction cups are presented, including testing and validation of available model and experimental approaches. In the second part, a detailed experimental study was conducted to obtain data for the comparison of the different soil water sampling systems. Finally, the numerical experiments of the suction cup influence were used for the interpretation of the experimental data. The main goals are summarized as follows: - Characterization of the suction cup activity domain (SCAD), suction cup extraction domain (SCED) and suction cup sampling area (SCSA) of active suction cups (definitions are given in Chapter 6). - Determination of the boundary conditions and soil properties [e.g. infiltration, applied suction, duration of water extraction, soil hydraulic properties and soil heterogeneity] affecting the activity domain, extraction domain and sampling area of a suction cup. - Identification of processes that change the travel time and travel time variance of solutes extracted by suction cups. - Validation of the numerically derived data with analytical and experimental data from literature. - Comparison of the experimental data obtained

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.

Does the Unemployement Benefit Institution Affect the Productivity of Workers? Evidence from a Field Experiment

NARCIS (Netherlands)

Blanco, M.; Dalton, P.S.; Vargas, J.F.

2013-01-01

Abstract: We investigate whether and how the type of unemployment bene t institution affects productivity. We designed a field experiment to compare workers' productivity under a welfare system, where the unemployed receive an unconditional monetary transfer, with their productivity under a workfare

Development of superconducting magnet systems for HIF Experiments

International Nuclear Information System (INIS)

Sabbi, Gian Luca; Faltens, A.; Leitzke, A.; Seidl, P.; Lund, S.; Martovetsky, N.; Chiesa, L.; Gung, C.; Minervini, J.; Schultz, J.; Goodzeit, C.; Hwang, P.; Hinson, W.; Meinke, R.

2004-01-01

The U.S. Heavy Ion Fusion program is developing superconducting focusing quadrupoles for near-term experiments and future driver accelerators. Following the fabrication and testing of several models, a baseline quadrupole design was selected and further optimized. The first prototype of the optimized design achieved a conductor-limited gradient of 132 T/m in a 70 mm bore, with measured field harmonics within 10 parts in 10 4 . In parallel, a compact focusing doublet was fabricated and tested using two of the first-generation quadrupoles. After assembly in the cryostat, both magnets reached their conductor-limited quench current. Further optimization steps are currently underway to improve the performance of the magnet system and reduce its cost. They include the fabrication and testing of a new prototype quadrupole with reduced field errors as well as improvements of the cryostat design for the focusing doublet. The prototype units will be installed in the HCX beamline at LBNL, to perform accelerator physics experiments and gain operational experience. Successful results in the present phase will make superconducting magnets a viable option for the next generation of integrated beam experiments

Equilibrium modeling of the TFCX poloidal field coil system

International Nuclear Information System (INIS)

Strickler, D.J.; Miller, J.B.; Rothe, K.E.; Peng, Y.K.M.

1984-04-01

The Toroidal Fusion Core Experiment (TFCX) isproposed to be an ignition device with a low safety factor (q approx. = 2.0), rf or rf-assisted startup, long inductive burn pulse (approx. 300 s), and an elongated plasma cross section (kappa = 1.6) with moderate triangularity (delta = 0.3). System trade studies have been carried out to assist in choosing an appropriate candidate for TFCX conceptual design. This report describes an important element in these system studies - the magnetohydrodynamic (MHD) equilibrium modeling of the TFCX poloidal field (PF) coil system and its impact on the choice of machine size. Reference design points for the all-super-conducting toroidal field (TF) coil (TFCX-S) and hybrid (TFCX-H) options are presented that satisfy given PF system criteria, including volt-second requirements during burn, mechanical configuration constraints, maximum field constraints at the superconducting PF coils, and plasma shape parameters. Poloidal coil current waveforms for the TFCX-S and TFCX-H reference designs consistent with the equilibrium requirements of the plasma startup, heating, and burn phases of a typical discharge scenario are calculated. Finally, a possible option for quasi-steady-state operation is discussed

Designing Fault-Injection Experiments for the Reliability of Embedded Systems

Science.gov (United States)

White, Allan L.

2012-01-01

This paper considers the long-standing problem of conducting fault-injections experiments to establish the ultra-reliability of embedded systems. There have been extensive efforts in fault injection, and this paper offers a partial summary of the efforts, but these previous efforts have focused on realism and efficiency. Fault injections have been used to examine diagnostics and to test algorithms, but the literature does not contain any framework that says how to conduct fault-injection experiments to establish ultra-reliability. A solution to this problem integrates field-data, arguments-from-design, and fault-injection into a seamless whole. The solution in this paper is to derive a model reduction theorem for a class of semi-Markov models suitable for describing ultra-reliable embedded systems. The derivation shows that a tight upper bound on the probability of system failure can be obtained using only the means of system-recovery times, thus reducing the experimental effort to estimating a reasonable number of easily-observed parameters. The paper includes an example of a system subject to both permanent and transient faults. There is a discussion of integrating fault-injection with field-data and arguments-from-design.

Parametric system studies of candidate TF coil system options for the Tokamak Fusion Core Experiment (TFCX)

International Nuclear Information System (INIS)

Reiersen, W.T.; Flanagan, C.A.; Miller, J.B.

1983-01-01

System studies were performed to determine the sensitivity of hybrid and superconducting toroidal field (TF) coil system options to maximum field at the TF coil and to field enhancement due to resistive insert coils. The studies were performed using Tokamak Fusion Core Experiment (TFCX) design assumptions, guidelines, and criteria and involved iterative execution of the Fusion Engineering Design Center (FEDC) systems code, magnetohydrodynamics (MHD) equilibrium code, and EFFI (a code to evaluate magnetic field strength). The results indicate that for TFCX with no minimum wall loading specified, a design point chosen solely on the basis of cost would likely be in the low-field region of design space where the cost advantage of hybrids is least apparent. However, as the desired neutron wall loading increases, the hybrid option suggests an increasing cost advantage over the all-superconducting option; this cost advantage is countered by increased complexity in design -- particularly in assembly and maintenance

Parametric system studies of candidate TF coil system options for the Tokamak Fusion Core Experiment (TFCX)

International Nuclear Information System (INIS)

Reiersen, W.T.; Flanagan, C.A.; Miller, J.B.

1983-01-01

System studies were performed to determine the sensitivity of hybrid and superconducting toroidal field (TF) coil system options to maximum field at the TF coil and to field enhancement due to resistive insert coils. The studies were performed using Tokamak Fusion Core Experiment (TFCX) design assumptions, guidelines, and criteria and involved iterative execution of the Fusion Engineering Design Center (FEDC) systems code, magnetohydrodynamics (MHD) equilibrium code, and EFFI (a code to evaluate magnetic field strength). The results indicate that for TFCX with no minimum wall loading specified, a design point chosen solely on the basis of cost would likely be in the low-field region of design space where the cost advantage of hybrids is least apparent. However, as the desired neutron wall loading increases, the hybrid option suggests an increasing cost advantage over the all-superconducting option; this cost advantage is countered by increased complexity in design - particularly in assembly and maintenance

Theoretical Investigation of Dynamic Properties of Magnetic Molecule Systems as Probed by NMR and Pulsed Fields Experiments

Energy Technology Data Exchange (ETDEWEB)

Rousochatzakis, Ioannis [Iowa State Univ., Ames, IA (United States)

2005-12-17

The field of molecular magnetism[l-6] has become a subject of intense theoretical and experimental interest and has rapidly evolved during the last years. This inter-disciplinary field concerns magnetic systems at the molecular or "nanoscopic" level, whose realization has become feasible due to recent advances in the field of chemical synthesis. The present theoretical work provides a first step towards exploiting the possibilities that are offered by probing magnetic molecules using external magnetic fields with high sweep rates. These probes, apart for providing information specific to magnetic molecules, offer the possibility of conducting a detailed study of the relaxational behavior of interacting spin systems as a result of their coupling with a "heat bath" and in particular the excitations of the host lattice. Development of a broad theoretical framework for dealing with relaxational phenomena induced by dynamical magnetic fields is indeed a worthy goal.

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…

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.

Development of a system for simultaneously generating triple extreme conditions for neutron scattering experiments

Energy Technology Data Exchange (ETDEWEB)

Ichimura, Shigeju [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

1998-10-01

We have developed new system available for controlling sample environment during the neutron scattering experiments. The system can simultaneously generate triple extreme conditions of low temperature, high magnetic field and high pressure. The system consists of : (1) a liquid-helium cryostat which enables the sample temperature range of 1.7 K to 200 K, (2) a superconducting magnet providing a vertical field up to 5 Tesla with antisymmetric split-coil geometry for polarized-beam experiments, and (3) a non-magnetic clamping high-pressure cell designed with the aim of generating hydrostatic pressure up to 2.5 Gpa. In the workshop, we will report the outline of the system and some results of performance tests using the system at JRR-3M of JAERI. (author)

Data acquisition system issues for large experiments

International Nuclear Information System (INIS)

Siskind, E.J.

2007-01-01

This talk consists of personal observations on two classes of data acquisition ('DAQ') systems for Silicon trackers in large experiments with which the author has been concerned over the last three or more years. The first half is a classic 'lessons learned' recital based on experience with the high-level debug and configuration of the DAQ system for the GLAST LAT detector. The second half is concerned with a discussion of the promises and pitfalls of using modern (and future) generations of 'system-on-a-chip' ('SOC') or 'platform' field-programmable gate arrays ('FPGAs') in future large DAQ systems. The DAQ system pipeline for the 864k channels of Si tracker in the GLAST LAT consists of five tiers of hardware buffers which ultimately feed into the main memory of the (two-active-node) level-3 trigger processor farm. The data formats and buffer volumes of these tiers are briefly described, as well as the flow control employed between successive tiers. Lessons learned regarding data formats, buffer volumes, and flow control/data discard policy are discussed. The continued development of platform FPGAs containing large amounts of configurable logic fabric, embedded PowerPC hard processor cores, digital signal processing components, large volumes of on-chip buffer memory, and multi-gigabit serial I/O capability permits DAQ system designers to vastly increase the amount of data preprocessing that can be performed in parallel within the DAQ pipeline for detector systems in large experiments. The capabilities of some currently available FPGA families are reviewed, along with the prospects for next-generation families of announced, but not yet available, platform FPGAs. Some experience with an actual implementation is presented, and reconciliation between advertised and achievable specifications is attempted. The prospects for applying these components to space-borne Si tracker detectors are briefly discussed

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

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…

The neutron imaging system fielded at the National Ignition Facility

Directory of Open Access Journals (Sweden)

Fittinghoff D.N.

2013-11-01

Full Text Available We have fielded a neutron imaging system at the National Ignition Facility to collect images of fusion neutrons produced in the implosion of inertial confinement fusion experiments and scattered neutrons from (n, n′ reactions of the source neutrons in the surrounding dense material. A description of the neutron imaging system is presented, including the pinhole array aperture, the line-of-sight collimation, the scintillator-based detection system and the alignment systems and methods. Discussion of the alignment and resolution of the system is presented. We also discuss future improvements to the system hardware.

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

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

Rethermalization of a field-reversed configuration plasma in translation experiments

International Nuclear Information System (INIS)

Himura, H.; Okada, S.; Sugimoto, S.; Goto, S.

1995-01-01

A translation experiment of field-reversed configuration (FRC) plasma is performed on the FIX machine [Shiokawa and Goto, Phys. Fluids B 5, 534 (1993)]. The translated FRC bounces between magnetic mirror fields at both ends of a confinement region. The plasma loses some of its axial kinetic energy when it is reflected by the magnetic mirror field, and eventually settles down in the confinement region. In this reflection process, the plasma temperature rises significantly. Such plasma rethermalization has been observed in OCT-L1 experiments [Ito et al., Phys. Fluids 30, 168 (1987)], but rarely in FRX-C/T experiments [Rej et al., Phys. Fluids 29, 852 (1986)]. It is found that the rethermalization depends on the relation between the plasma temperature and the translation velocity. The rethermalization occurs only in the case where the translation velocity exceeds the sound velocity. This result implies the rethermalization is caused by a shock wave induced within the FRC when the plasma is reflected by the magnetic mirror field. copyright 1995 American Institute of Physics

Measurement and tricubic interpolation of the magnetic field for the OLYMPUS experiment

Energy Technology Data Exchange (ETDEWEB)

Bernauer, J.C. [Massachusetts Institute of Technology, Laboratory for Nuclear Science, Cambridge, MA (United States); Diefenbach, J. [Hampton University, Hampton, VA (United States); Elbakian, G. [Alikhanyan National Science Laboratory (Yerevan Physics Institute), Yerevan (Armenia); Gavrilov, G. [Petersburg Nuclear Physics Institute, Gatchina (Russian Federation); Goerrissen, N. [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany); Hasell, D.K.; Henderson, B.S. [Massachusetts Institute of Technology, Laboratory for Nuclear Science, Cambridge, MA (United States); Holler, Y. [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany); Karyan, G. [Alikhanyan National Science Laboratory (Yerevan Physics Institute), Yerevan (Armenia); Ludwig, J. [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany); Marukyan, H. [Alikhanyan National Science Laboratory (Yerevan Physics Institute), Yerevan (Armenia); Naryshkin, Y. [Petersburg Nuclear Physics Institute, Gatchina (Russian Federation); O' Connor, C.; Russell, R.L.; Schmidt, A. [Massachusetts Institute of Technology, Laboratory for Nuclear Science, Cambridge, MA (United States); Schneekloth, U. [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany); Suvorov, K.; Veretennikov, D. [Petersburg Nuclear Physics Institute, Gatchina (Russian Federation)

2016-07-01

The OLYMPUS experiment used a 0.3 T toroidal magnetic spectrometer to measure the momenta of outgoing charged particles. In order to accurately determine particle trajectories, knowledge of the magnetic field was needed throughout the spectrometer volume. For that purpose, the magnetic field was measured at over 36,000 positions using a three-dimensional Hall probe actuated by a system of translation tables. We used these field data to fit a numerical magnetic field model, which could be employed to calculate the magnetic field at any point in the spectrometer volume. Calculations with this model were computationally intensive; for analysis applications where speed was crucial, we pre-computed the magnetic field and its derivatives on an evenly spaced grid so that the field could be interpolated between grid points. We developed a spline-based interpolation scheme suitable for SIMD implementations, with a memory layout chosen to minimize space and optimize the cache behavior to quickly calculate field values. This scheme requires only one-eighth of the memory needed to store necessary coefficients compared with a previous scheme (Lekien and Marsden, 2005 [1]). This method was accurate for the vast majority of the spectrometer volume, though special fits and representations were needed to improve the accuracy close to the magnet coils and along the toroidal axis.

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)

Megagauss field generation for high-energy-density plasma science experiments

International Nuclear Information System (INIS)

Rovang, Dean Curtis; Struve, Kenneth William; Porter, John Larry Jr.

2008-01-01

There is a need to generate magnetic fields both above and below 1 megagauss (100 T) with compact generators for laser-plasma experiments in the Beamlet and Petawatt test chambers for focused research on fundamental properties of high energy density magnetic plasmas. Some of the important topics that could be addressed with such a capability are magnetic field diffusion, particle confinement, plasma instabilities, spectroscopic diagnostic development, material properties, flux compression, and alternate confinement schemes, all of which could directly support experiments on Z. This report summarizes a two-month study to develop preliminary designs of magnetic field generators for three design regimes. These are, (1) a design for a relatively low-field (10 to 50 T), compact generator for modest volumes (1 to 10 cm3), (2) a high-field (50 to 200 T) design for smaller volumes (10 to 100 mm3), and (3) an extreme field (greater than 600 T) design that uses flux compression. These designs rely on existing Sandia pulsed-power expertise and equipment, and address issues of magnetic field scaling with capacitor bank design and field inductance, vacuum interface, and trade-offs between inductance and coil designs

Regional co-operation in the nuclear field: The Nordic experience

International Nuclear Information System (INIS)

Marcus, F.R.

1983-01-01

Experience from 25 years of co-operation in the nuclear field between the Nordic countries is described. A pragmatic approach with a minimum of formalism is used. The co-operation takes place mainly through ''horizontal'' channels between corresponding bodies in the different countries - safety authorities, research institutions, electricity producers, etc. In addition, a ''vertical'' co-ordination between these different circles is accomplished through a Nordic Liaison Committee. The experience shows that valuable results can be obtained, mainly through rationalization and improved use of resources. Difficulties, which are inherent in international co-operation, can be reduced, provided that there is a strong political will, an efficient system to promote contacts, and a flexible financing scheme. Apart from the benefits obtained in each of the countries - whether or not it has its own nuclear power - particular advantages accrue when a ''Nordic group'' can present co-ordinated viewpoints on the international scene. (author)

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.

Hall field-induced magnetoresistance oscillations of a two-dimensional electron system

International Nuclear Information System (INIS)

Kunold, A.; Torres, M.

2008-01-01

We develop a model of the nonlinear response to a dc electrical current of a two-dimensional electron system (2DES) placed on a magnetic field. Based on the exact solution to the Schroedinger equation in arbitrarily strong electric and magnetic fields, and separating the relative and guiding center coordinates, a Kubo-like formula for the current is worked out as a response to the impurity scattering. Self-consistent expressions determine the longitudinal and Hall components of the electric field in terms of the dc current. The differential resistivity displays strong Hall field-induced oscillations, in agreement with the main features of the phenomenon observed in recent experiments

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...

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.

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…

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.

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 (�

Star camera aspect system suitable for use in balloon experiments

International Nuclear Information System (INIS)

Hunter, S.D.; Baker, R.G.

1985-01-01

A balloon-borne experiment containing a star camera aspect system was designed, built, and flown. This system was designed to provide offset corrections to the magnetometer and inclinometer readings used to control an azimuth and elevation pointed experiment. The camera is controlled by a microprocessor, including commendable exposure and noise rejection threshold, as well as formatting the data for telemetry to the ground. As a background program, the microprocessor runs the aspect program to analyze a fraction of the pictures taken so that aspect information and offset corrections are available to the experiment in near real time. The analysis consists of pattern recognition of the star field with a star catalog in ROM memory and a least squares calculation. The performance of this system in ground based tests is described. It is part of the NASA/GSFC High Energy Gamma-Ray Balloon Instrument (2)

Electromagnetic fields in biological systems

National Research Council Canada - National Science Library

Lin, James C

2012-01-01

"Focusing on exposure, induced fields, and absorbed energy, this volume covers the interaction of electromagnetic fields and waves with biological systems, spanning static fields to terahertz waves...

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.)

Overview of the Bushland Evapotranspiration and Agricultural Remote sensing EXperiment 2008 (BEAREX08): A field experiment evaluating methods for quantifying ET at multiple scales

Science.gov (United States)

Evett, Steven R.; Kustas, William P.; Gowda, Prasanna H.; Anderson, Martha C.; Prueger, John H.; Howell, Terry A.

2012-12-01

In 2008, scientists from seven federal and state institutions worked together to investigate temporal and spatial variations of evapotranspiration (ET) and surface energy balance in a semi-arid irrigated and dryland agricultural region of the Southern High Plains in the Texas Panhandle. This Bushland Evapotranspiration and Agricultural Remote sensing EXperiment 2008 (BEAREX08) involved determination of micrometeorological fluxes (surface energy balance) in four weighing lysimeter fields (each 4.7 ha) containing irrigated and dryland cotton and in nearby bare soil, wheat stubble and rangeland fields using nine eddy covariance stations, three large aperture scintillometers, and three Bowen ratio systems. In coordination with satellite overpasses, flux and remote sensing aircraft flew transects over the surrounding fields and region encompassing an area contributing fluxes from 10 to 30 km upwind of the USDA-ARS lysimeter site. Tethered balloon soundings were conducted over the irrigated fields to investigate the effect of advection on local boundary layer development. Local ET was measured using four large weighing lysimeters, while field scale estimates were made by soil water balance with a network of neutron probe profile water sites and from the stationary flux systems. Aircraft and satellite imagery were obtained at different spatial and temporal resolutions. Plot-scale experiments dealt with row orientation and crop height effects on spatial and temporal patterns of soil surface temperature, soil water content, soil heat flux, evaporation from soil in the interrow, plant transpiration and canopy and soil radiation fluxes. The BEAREX08 field experiment was unique in its assessment of ET fluxes over a broad range in spatial scales; comparing direct and indirect methods at local scales with remote sensing based methods and models using aircraft and satellite imagery at local to regional scales, and comparing mass balance-based ET ground truth with eddy covariance

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.

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)

Tackling the Reproducibility Problem in Systems Research with Declarative Experiment Specifications

Energy Technology Data Exchange (ETDEWEB)

Jimenez, Ivo [Univ. of California, Santa Cruz, CA (United States); Maltzahn, Carlos [Univ. of California, Santa Cruz, CA (United States); Lofstead, Jay [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Moody, Adam [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Mohror, Kathryn [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Arpaci-Dusseau, Remzi [Univ. of Wisconsin, Madison, WI (United States); Arpaci-Dusseau, Andrea [Univ. of Wisconsin, Madison, WI (United States)

2015-05-04

Validating experimental results in the field of computer systems is a challenging task, mainly due to the many changes in software and hardware that computational environments go through. Determining if an experiment is reproducible entails two separate tasks: re-executing the experiment and validating the results. Existing reproducibility efforts have focused on the former, envisioning techniques and infrastructures that make it easier to re-execute an experiment. In this work we focus on the latter by analyzing the validation workflow that an experiment re-executioner goes through. We notice that validating results is done on the basis of experiment design and high-level goals, rather than exact quantitative metrics. Based on this insight, we introduce a declarative format for specifying the high-level components of an experiment as well as describing generic, testable conditions that serve as the basis for validation. We present a use case in the area of storage systems to illustrate the usefulness of this approach. We also discuss limitations and potential benefits of using this approach in other areas of experimental systems research.

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

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.)

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.)

LASE measurements of water vapor and aerosol profiles during the Plains Elevated Convection at Night (PECAN) field experiment

Science.gov (United States)

Nehrir, A. R.; Ferrare, R. A.; Kooi, S. A.; Butler, C. F.; Notari, A.; Hair, J. W.; Collins, J. E., Jr.; Ismail, S.

2015-12-01

The Lidar Atmospheric Sensing Experiment (LASE) system was deployed on the NASA DC-8 aircraft during the Plains Elevated Convection At Night (PECAN) field experiment, which was conducted during June-July 2015 over the central and southern plains. LASE is an active remote sensor that employs the differential absorption lidar (DIAL) technique to measure range resolved profiles of water vapor and aerosols above and below the aircraft. The DC-8 conducted nine local science flights from June 30- July 14 where LASE sampled water vapor and aerosol fields in support of the PECAN primary science objectives relating to better understanding nocturnal Mesoscale Convective Systems (MCSs), Convective Initiation (CI), the Low Level Jet (LLJ), bores, and to compare different airborne and ground based measurements. LASE observed large spatial and temporal variability in water vapor and aerosol distributions in advance of nocturnal MCSs, across bores resulting from MCS outflow boundaries, and across the LLJ associated with the development of MCSs and CI. An overview of the LASE data collected during the PECAN field experiment will be presented where emphasis will be placed on variability of water vapor profiles in the vicinity of severe storms and intense convection in the central and southern plains. Preliminary comparisons show good agreement between coincident LASE and radiosonde water vapor profiles. In addition, an advanced water vapor DIAL system being developed at NASA Langley will be discussed.

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…

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.

Experiences of using mobile technologies and virtual field tours in Physical Geography: implications for hydrology education

Directory of Open Access Journals (Sweden)

D. G. Kingston

2012-05-01

Full Text Available Education in hydrology is changing rapidly due to diversification of students, emergent major scientific and practical challenges that our discipline must engage with, shifting pedagogic ideas and higher education environments, the need for students to develop new discipline specific and transferrable skills, and the advent of innovative technologies for learning and teaching. This paper focuses on new technologies in the context of learning and teaching in Physical Geography and reflects on the implications of our experiences for education in hydrology. We evaluate the experience of designing and trialling novel mobile technology-based field exercises and a virtual field tour for a Year 1 undergraduate Physical Geography module at a UK university. The new exercises are based on using and obtaining spatial data, operation of meteorological equipment (explained using an interactive DVD, and include introductions to global positioning systems (GPS and geographical information systems (GIS. The technology and exercises were well received in a pilot study and subsequent rolling-out to the full student cohort (∼150 students. A statistically significant improvement in marks was observed following the redesign. Although the students enjoyed using mobile technology, the increased interactivity and opportunity for peer learning were considered to be the primary benefits by students. This is reinforced further by student preference for the new interactive virtual field tour over the previous "show-and-tell" field exercise. Despite the new exercises having many advantages, exercise development was not trivial due to the high start-up costs, the need for provision of sufficient technical support and the relative difficulty of making year-to-year changes (to the virtual field tour in particular. Our experiences are highly relevant to the implementation of novel learning and teaching technologies in hydrology education.

Experiences of using mobile technologies and virtual field tours in Physical Geography: implications for hydrology education

Science.gov (United States)

Kingston, D. G.; Eastwood, W. J.; Jones, P. I.; Johnson, R.; Marshall, S.; Hannah, D. M.

2012-05-01

Education in hydrology is changing rapidly due to diversification of students, emergent major scientific and practical challenges that our discipline must engage with, shifting pedagogic ideas and higher education environments, the need for students to develop new discipline specific and transferrable skills, and the advent of innovative technologies for learning and teaching. This paper focuses on new technologies in the context of learning and teaching in Physical Geography and reflects on the implications of our experiences for education in hydrology. We evaluate the experience of designing and trialling novel mobile technology-based field exercises and a virtual field tour for a Year 1 undergraduate Physical Geography module at a UK university. The new exercises are based on using and obtaining spatial data, operation of meteorological equipment (explained using an interactive DVD), and include introductions to global positioning systems (GPS) and geographical information systems (GIS). The technology and exercises were well received in a pilot study and subsequent rolling-out to the full student cohort (∼150 students). A statistically significant improvement in marks was observed following the redesign. Although the students enjoyed using mobile technology, the increased interactivity and opportunity for peer learning were considered to be the primary benefits by students. This is reinforced further by student preference for the new interactive virtual field tour over the previous "show-and-tell" field exercise. Despite the new exercises having many advantages, exercise development was not trivial due to the high start-up costs, the need for provision of sufficient technical support and the relative difficulty of making year-to-year changes (to the virtual field tour in particular). Our experiences are highly relevant to the implementation of novel learning and teaching technologies in hydrology education.

Multimode marine engine room simulation system based on field bus technology

Science.gov (United States)

Zheng, Huayao; Deng, Linlin; Guo, Yi

2003-09-01

Developing multi mode MER (Marine Engine Room) Labs is the main work in Marine Simulation Center, which is the key lab of Communication Ministry of China. It includes FPP (Fixed Pitch Propeller) and CPP (Controllable Pitch Propeller) mode MER simulation systems, integrated electrical propulsion mode MER simulation system, physical mode MER lab, etc. FPP mode simulation system, which was oriented to large container ship, had been completed since 1999, and got second level of Shanghai Municipal Science and Technical Progress award. This paper mainly introduces the recent development and achievements of Marine Simulation Center. Based on the Lon Works field bus, the structure characteristics and control strategies of completely distributed intelligent control network are discussed. The experiment mode of multi-nodes field bus detection and control system is described. Besides, intelligent fault diagnosis technology about some mechatronics integration control systems explored is also involved.

Evaluation of the user experience of "astronaut training device": an immersive, vr-based, motion-training system

Science.gov (United States)

Yue, Kang; Wang, Danli; Yang, Xinpan; Hu, Haichen; Liu, Yuqing; Zhu, Xiuqing

2016-10-01

To date, as the different application fields, most VR-based training systems have been different. Therefore, we should take the characteristics of application field into consideration and adopt different evaluation methods when evaluate the user experience of these training systems. In this paper, we propose a method to evaluate the user experience of virtual astronauts training system. Also, we design an experiment based on the proposed method. The proposed method takes learning performance as one of the evaluation dimensions, also combines with other evaluation dimensions such as: presence, immersion, pleasure, satisfaction and fatigue to evaluation user experience of the System. We collect subjective and objective data, the subjective data are mainly from questionnaire designed based on the evaluation dimensions and user interview conducted before and after the experiment. While the objective data are consisted of Electrocardiogram (ECG), reaction time, numbers of reaction error and the video data recorded during the experiment. For the analysis of data, we calculate the integrated score of each evaluation dimension by using factor analysis. In order to improve the credibility of the assessment, we use the ECG signal and reaction test data before and after experiment to validate the changes of fatigue during the experiment, and the typical behavioral features extracted from the experiment video to explain the result of subjective questionnaire. Experimental results show that the System has a better user experience and learning performance, but slight visual fatigue exists after experiment.

A System for Electromagnetic Field Conversion

DEFF Research Database (Denmark)

2003-01-01

A system is provided for conversion of a first electromagnetic field into a desired second electromagnetic field, for example for coupling modes between waveguides or into microstructured waveguides. The system comprises a complex spatial electromagnetic field converter that is positioned...... for reception of at least a part of the first electromagnetic field and that is adapted for conversion of the received field into the desired electromagnetic field, and wherein at least one of the first and second fields matches a mode of a microstructured waveguide. It is an important advantage of the present...

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

The generation and amplification of intergalactic magnetic fields in analogue laboratory experiments with high power lasers

Science.gov (United States)

Gregori, G.; Reville, B.; Miniati, F.

2015-11-01

The advent of high-power laser facilities has, in the past two decades, opened a new field of research where astrophysical environments can be scaled down to laboratory dimensions, while preserving the essential physics. This is due to the invariance of the equations of magneto-hydrodynamics to a class of similarity transformations. Here we review the relevant scaling relations and their application in laboratory astrophysics experiments with a focus on the generation and amplification of magnetic fields in cosmic environment. The standard model for the origin of magnetic fields is a multi stage process whereby a vanishing magnetic seed is first generated by a rotational electric field and is then amplified by turbulent dynamo action to the characteristic values observed in astronomical bodies. We thus discuss the relevant seed generation mechanisms in cosmic environment including resistive mechanism, collision-less and fluid instabilities, as well as novel laboratory experiments using high power laser systems aimed at investigating the amplification of magnetic energy by magneto-hydrodynamic (MHD) turbulence. Future directions, including efforts to model in the laboratory the process of diffusive shock acceleration are also discussed, with an emphasis on the potential of laboratory experiments to further our understanding of plasma physics on cosmic scales.

A balloon-borne experiment to investigate the Martian magnetic field

Science.gov (United States)

Schwingenschuh, K.; Feldhofer, H.; Koren, W.; Jernej, I.; Stachel, M.; Riedler, W.; Slamanig, H.; Auster, H.-U.; Rustenbach, J.; Fornacon, H. K.; Schenk, H. J.; Hillenmaier, O.; Haerendel, G.; Yeroshenko, Ye.; Styashkin, V.; Zaroutzky, A.; Best, A.; Scholz, G.; Russell, C. T.; Means, J.; Pierce, D.; Luhmann, J. G.

1996-03-01

The Space Research Institute of the Austrian Academy, of Sciences (Graz, Austria) in cooperation with MPE (Berlin, Germany), GFZ Potsdam (Obs. Niemegk, Germany) IZMIRAN/IOFAN (Moscow, Russian) and IGPP/UCLA (Los Angeles, USA) is designing the magnetic field experiment MAGIBAL (MAGnetic field experiment aboard a martian BALloon) to investigate the magnetic field on the surface of Mars. The dual sensor fluxgate magnetometer is part of the MARS-98/MARS-TOGETHER balloon payload. During a ten days period the balloon will float over a distance of about 2000 km at altitudes between 0 and 4 km. Due to the limited power and telemetry allocation the magnetometer can transmit only one vector per ten seconds and spectral information in the frequency range from 2 - 25 Hz. The dynamic range is +/- 2000 nT. The main scientific objectives of the experiment are: • Determination of the magnetism of the Martian rocks • Investigation of the leakage of the solar wind induced magnetosphere using the correlation between orbiter and balloon observations • Measurement of the magnetic field profile between the orbiter and the surface of Mars during the descent phase of the balloon. Terrestrial test flights with a hot air balloon were performed in order to test the original MAGIBAL equipment under balloon flight conditions.

The BLLAST field experiment: Boundary-Layer Late Afternoon and Sunset Turbulence

Science.gov (United States)

Lothon, M.; Lohou, F.; Pino, D.; Couvreux, F.; Pardyjak, E. R.; Reuder, J.; Vilà-Guerau de Arellano, J.; Durand, P.; Hartogensis, O.; Legain, D.; Augustin, P.; Gioli, B.; Lenschow, D. H.; Faloona, I.; Yagüe, C.; Alexander, D. C.; Angevine, W. M.; Bargain, E.; Barrié, J.; Bazile, E.; Bezombes, Y.; Blay-Carreras, E.; van de Boer, A.; Boichard, J. L.; Bourdon, A.; Butet, A.; Campistron, B.; de Coster, O.; Cuxart, J.; Dabas, A.; Darbieu, C.; Deboudt, K.; Delbarre, H.; Derrien, S.; Flament, P.; Fourmentin, M.; Garai, A.; Gibert, F.; Graf, A.; Groebner, J.; Guichard, F.; Jiménez, M. A.; Jonassen, M.; van den Kroonenberg, A.; Magliulo, V.; Martin, S.; Martinez, D.; Mastrorillo, L.; Moene, A. F.; Molinos, F.; Moulin, E.; Pietersen, H. P.; Piguet, B.; Pique, E.; Román-Cascón, C.; Rufin-Soler, C.; Saïd, F.; Sastre-Marugán, M.; Seity, Y.; Steeneveld, G. J.; Toscano, P.; Traullé, O.; Tzanos, D.; Wacker, S.; Wildmann, N.; Zaldei, A.

2014-10-01

Due to the major role of the sun in heating the earth's surface, the atmospheric planetary boundary layer over land is inherently marked by a diurnal cycle. The afternoon transition, the period of the day that connects the daytime dry convective boundary layer to the night-time stable boundary layer, still has a number of unanswered scientific questions. This phase of the diurnal cycle is challenging from both modelling and observational perspectives: it is transitory, most of the forcings are small or null and the turbulence regime changes from fully convective, close to homogeneous and isotropic, toward a more heterogeneous and intermittent state. These issues motivated the BLLAST (Boundary-Layer Late Afternoon and Sunset Turbulence) field campaign that was conducted from 14 June to 8 July 2011 in southern France, in an area of complex and heterogeneous terrain. A wide range of instrumented platforms including full-size aircraft, remotely piloted aircraft systems, remote-sensing instruments, radiosoundings, tethered balloons, surface flux stations and various meteorological towers were deployed over different surface types. The boundary layer, from the earth's surface to the free troposphere, was probed during the entire day, with a focus and intense observation periods that were conducted from midday until sunset. The BLLAST field campaign also provided an opportunity to test innovative measurement systems, such as new miniaturized sensors, and a new technique for frequent radiosoundings of the low troposphere. Twelve fair weather days displaying various meteorological conditions were extensively documented during the field experiment. The boundary-layer growth varied from one day to another depending on many contributions including stability, advection, subsidence, the state of the previous day's residual layer, as well as local, meso- or synoptic scale conditions. Ground-based measurements combined with tethered-balloon and airborne observations captured the

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…

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.

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.

Porous media experience applicable to field evaluation for compressed air energy storage

Energy Technology Data Exchange (ETDEWEB)

Allen, R.D.; Gutknecht, P.J.

1980-06-01

A survey is presented of porous media field experience that may aid in the development of a compressed air energy storage field demonstration. Work done at PNL and experience of other groups and related industries is reviewed. An overall view of porous media experience in the underground storage of fluids is presented. CAES experience consists of site evaluation and selection processes used by groups in California, Kansas, and Indiana. Reservoir design and field evaluation of example sites are reported. The studies raised questions about compatibility with depleted oil and gas reservoirs, storage space rights, and compressed air regulations. Related experience embraces technologies of natural gas, thermal energy, and geothermal and hydrogen storage. Natural gas storage technology lends the most toward compressed air storage development, keeping in mind the respective differences between stored fluids, physical conditions, and cycling frequencies. Both fluids are injected under pressure into an aquifer to form a storage bubble confined between a suitable caprock structure and partially displaced ground water. State-of-the-art information is summarized as the necessary foundation material for field planning. Preliminary design criteria are given as recommendations for basic reservoir characteristics. These include geometric dimensions and storage matrix properties such as permeability. Suggested ranges are given for injection air temperature and reservoir pressure. The second step in developmental research is numerical modeling. Results have aided preliminary design by analyzing injection effects upon reservoir pressure, temperature and humidity profiles. Results are reported from laboratory experiments on candidate sandstones and caprocks. Conclusions are drawn, but further verification must be done in the field.

Impacts of distinct observations during the 2009 Prince William Sound field experiment: A data assimilation study

Science.gov (United States)

Li, Z.; Chao, Y.; Farrara, J.; McWilliams, J. C.

2012-12-01

A set of data assimilation experiments, known as Observing System Experiments (OSEs), are performed to assess the relative impacts of different types of observations acquired during the 2009 Prince William Sound Field Experiment. The observations assimilated consist primarily of three types: High Frequency (HF) radar surface velocities, vertical profiles of temperature/salinity (T/S) measured by ships, moorings, Autonomous Underwater Vehicles and gliders, and satellite sea surface temperatures (SSTs). The impact of all the observations, HF radar surface velocities, and T/S profiles is assessed. Without data assimilation, a frequently occurring cyclonic eddy in the central Sound is overly persistent and intense. The assimilation of the HF radar velocities effectively reduces these biases and improves the representation of the velocities as well as the T/S fields in the Sound. The assimilation of the T/S profiles improves the large scale representation of the temperature/salinity and also the velocity field in the central Sound. The combination of the HF radar surface velocities and sparse T/S profiles results in an observing system capable of representing the circulation in the Sound reliably and thus producing analyses and forecasts with useful skill. It is suggested that a potentially promising observing network could be based on satellite SSHs and SSTs along with sparse T/S profiles, and future satellite SSHs with wide swath coverage and higher resolution may offer excellent data that will be of great use for predicting the circulation in the Sound.

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

VME as a front-end electronics system in high energy physics experiments

International Nuclear Information System (INIS)

Ohska, T.K.

1990-01-01

It is only a few years since the VME became a standard system, yet the VME system is already so much more popular than other systems. The VME system was developed for industrial applications and not for the scientific research, and high energy physics field is a tiny market when compared with the industrial market. Considerations made here indicate that the VME system would be a good one for a rear-end system, but would not be a good candidate for front-end electronics in physics experiments. Furthermore, there is a fear that the VXI bus could become popular in this field of instrumentation since the VXI system is backed up by major suppliers of instrumentation in the high energy physics field. VXI would not be an adequate system for front-end electronics, yet advertised to be one. It would be worse to see the VXI system to become a standard system for high energy physics instrumentation than the VME system to be one. The VXI system would do a mediocre job so that people might be misled to think that the VXI system can be used as front-end system. (N.K.)

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

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

Innovating the Experience of Peer Learning and Earth Science Education in the Field

Science.gov (United States)

Scoates, J. S.; Hanano, D. W.; Weis, D.; Bilenker, L.; Sherman, S. B.; Gilley, B.

2017-12-01

The use of active learning and collaborative strategies is widely gaining momentum at the university level and is ideally suited to field instructional settings. Peer learning, when students learn with and from each other, is based on the principle that students learn in a more profound way by explaining their ideas to others and by participating in activities in which they can learn from their peers. The Multidisciplinary Applied Geochemistry Network (MAGNET), an NSERC Collaborative Research and Training Experience (CREATE) initiative in Canada, recently experimented with this approach during its fourth annual workshop in August 2016. With a group of 25 geochemistry graduate students from universities across Canada, three remarkable field sites in Montana and Wyoming were explored: the Stillwater Complex, the Beartooth Mountains, and Yellowstone National Park. Rather than developing a rigorous teaching curriculum led by faculty, groups of students were tasked with designing and delivering half-day teaching modules that included field activities at each of the locations. Over the course of two months and with feedback from mentors, the graduate students transformed their ideas into formal lesson plans, complete with learning goals, a schedule of teaching activities, equipment lists, and plans for safety and environmental mitigation. This shift, from teacher-centered to learner-centered education, requires students to take greater initiative and responsibility for their own learning and development. We highlight the goals, structure and implementation of the workshop, as well as some of the successes and challenges. We also present the results of participant feedback taken immediately after each lesson and both pre- and post-trip surveys. The outdoor classroom and hands-on activities accelerated learning of field techniques and enhanced understanding of complex geological systems and processes. The trainee-led format facilitated peer knowledge transfer and the

Program system for calculating streaming neutron radiation field in reactor cavity

International Nuclear Information System (INIS)

He Zhongliang; Zhao Shu.

1986-01-01

The A23 neutron albedo data base based on Monte Carlo method well agrees with SAIL albedo data base. RSCAM program system, using Monte Carlo method with albedo approach, is used to calculate streaming neutron radiation field in reactor cavity and containment operating hall. The dose rate distributions calculated with RSCAM in square concrete duct well agree with experiments

Development of a summer field-based hydrogeology research experience for undergraduates

Science.gov (United States)

Singha, K.

2011-12-01

A critical problem in motivating and training the next generation of environmental scientists is providing them with an integrated scientific experience that fosters a depth of understanding and helps them build a network of colleagues for their future. As the education part of an NSF-funded CAREER proposal, I have developed a three-week summer research experience for undergraduate students that links their classroom education with field campaigns aiming to make partial differential equations come "alive" in a practical, applied setting focused on hydrogeologic processes. This course has been offered to freshman- to junior-level undergraduate students from Penn State and also the three co-operating Historically Black Universities (HBUs)--Jackson State University, Fort Valley State University, and Elizabeth City State University-since 2009. Broad learning objectives include applying their knowledge of mathematics, science, and engineering to flow and transport processes in the field and communicating science effectively in poster and oral format. In conjunction with ongoing research about solute transport, students collected field data in the Shale Hills Critical Zone Observatory in Central Pennsylvania, including slug and pumping tests, ground-penetrating radar, electrical resistivity imaging, wireline logging, and optical televiewers, among other instruments. Students conducted tracer tests, where conservative solutes are introduced into a local stream and monitored. Students also constructed numerical models using COMSOL Multiphysics, a research-grade code that can be used to model any physical system; with COMSOL, students create models without needing to be trained in computer coding. With guidance, students built basic models of fluid flow and transport to visualize how heterogeneity of hydraulic and transport properties or variations in forcing functions impact their results. The development of numerical models promoted confidence in predicting flow and

O and M Experience with computer based system at captive power plant, HWP Manuguru

International Nuclear Information System (INIS)

Basu, S.; Kulkarni, R.S.

1992-01-01

Distributed digital control system has been the latest trend in the field of instrumentation and control system. In this paper effort is made to bring out the operation and maintenance experience of ASEA make DDC system at captive power plant, Heavy Water Project(HWP), Manuguru. (author). 2 refs., 1 fig

Experiments with arbitrary networks in time-multiplexed delay systems

Science.gov (United States)

Hart, Joseph D.; Schmadel, Don C.; Murphy, Thomas E.; Roy, Rajarshi

2017-12-01

We report a new experimental approach using an optoelectronic feedback loop to investigate the dynamics of oscillators coupled on large complex networks with arbitrary topology. Our implementation is based on a single optoelectronic feedback loop with time delays. We use the space-time interpretation of systems with time delay to create large networks of coupled maps. Others have performed similar experiments using high-pass filters to implement the coupling; this restricts the network topology to the coupling of only a few nearest neighbors. In our experiment, the time delays and coupling are implemented on a field-programmable gate array, allowing the creation of networks with arbitrary coupling topology. This system has many advantages: the network nodes are truly identical, the network is easily reconfigurable, and the network dynamics occur at high speeds. We use this system to study cluster synchronization and chimera states in both small and large networks of different topologies.

Lightning magnetic field measuring system in Bogota

OpenAIRE

Escobar Alvarado, Oscar Fernardo

2013-01-01

This thesis presents the configuration and performance of a lightning radiated electromagnetic field measuring system in Bogotá Colombia. The system is composed by both magnetic and electric field measuring systems working as separated sensors. The aim of the thesis is the design and construction of a Magnetic Field Measuring System and the implementation of a whole lightning measuring system in Bogotá. The theoretical background, design process, construction and implementation of the system ...

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.…

SUPERCONDUCTING COMBINED FUNCTION MAGNET SYSTEM FOR J-PARC NEUTRINO EXPERIMENT

International Nuclear Information System (INIS)

2004-01-01

The J-PARC Neutrino Experiment, the construction of which starts in JFY 2004, will use a superconducting magnet system for its primary proton beam line. The system, which bends the 50 GeV 0.75 MW proton beam by about 80 degrees, consists of 28 superconducting combined function magnets. The magnets utilize single layer left/right asymmetric coils that generate a dipole field of 2.6 T and a quadrupole field of 18.6 T/m with the operation current of about 7.35 kA. The system also contains a few conduction cooled superconducting corrector magnets that serve as vertical and horizontal steering magnets. All the magnets are designed to provide a physical beam aperture of 130 mm in order to achieve a large beam acceptance. Extensive care is also required to achieve safe operation with the high power proton beam. The paper summarizes the system design as well as some safety analysis results

Using Novel Laboratory Incubations and Field Experiments to Identify the Source and Fate of Reactive Organic Carbon in an Arsenic-contaminated Aquifer System

Science.gov (United States)

Stahl, M.; Tarek, M. H.; Badruzzaman, B.; Harvey, C. F.

2017-12-01

Characterizing the sources and fate of organic matter (OM) within aquifer systems is key to our understanding of both the broader global carbon cycle as well as the quality of our groundwater resources. The linkage between the subsurface carbon cycle and groundwater quality is perhaps nowhere more apparent than in the aquifer systems of South and Southeast Asia, where the contamination of groundwater with geogenic arsenic (As) is widespread and threatens the health of millions of individuals. OM fuels the biogeochemical processes driving As mobilization within these aquifers, however the source (i.e., modern surface-derived or aged sedimentary OM) of the reactive OM is widely debated. To characterize the sources of OM driving aquifer redox processes we tracked DIC and DOC concentrations and isotopes (stable and radiocarbon) along groundwater flow-paths and beneath an instrumented study pond at a field site in Bangladesh. We also conducted a set of novel groundwater incubation experiments, where we carbon-dated the DOC at the start and end of a experiment in order to determine the age of the OM that was mineralized. Our carbon/isotope balance reveals that aquifer recharge introduces a large quantity of young (i.e. near modern) OM that is efficiently mineralized within the upper few meters of the aquifer, effectively limiting this pool of reactive surface-sourced OM from being transported deeper into the aquifer where significant As mobilization takes place. The OM mineralized past the upper few meters is an aged, sedimentary source. Consistent with our field data, our incubation experiments show that past the upper few meters of the aquifer the reactive DOC is significantly older than the bulk DOC and has an age consistent with sedimentary OM. Combining our novel set of incubation experiments and a carbon/isotope balance along groundwater flow-paths and beneath our study pond we have identified the sources of reactive OM across different aquifer depths in a

Reentering the Gravitational Fringe Field of the Solar System

Science.gov (United States)

Fisher, P. C.

A 1998 proposal to the National Aeronautics and Space Administration (NASA) described how to update an earlier proposal outline for an experiment involving a manned spacecraft that traveled to just outside the gravitational field of the solar system. The recent proposal briefly describes how to initiate a 25-year program to launch a seven-year mission. Very little thought has been given to astronomical/astrophysical investigations that might be carried out over seven years, but one or more generations of NASA's Terrestrial Planet Finder program might be included. Only a little serious thought has been given to how to reenter the solar system's gravitational fringe field, but access to several procedures and three-fold redundancy seems desirable. Some details of the proposed paper study will be given. Non-responsibility statement, from source document of calendar 1973. This document was prepared while the author was on an unpaid leave of absence from The Lockheed Missiles and Space Company (LMSC) of Palo Alto, California. The comments made herein are partly the results of experiments carried out over a number of years. For a portion of this time, both NASA and LMSC financed the author's space astronomy investigations. It may be that either or both these institutions may possess some proprietary rights to portions of the ideas and information presented. This work was supported by Ruffner Associates, Inc.

Enhancing the Understanding of Marine Ecosystems through Teleducation and Field Experiences

Science.gov (United States)

Macko, S.

2006-12-01

This project is an outreach and education program with a partner in the K-12 schools at Accomack County on the Eastern Shore of Virginia. It endeavors to build a community more knowledgeable of the importance the ocean plays daily in our lives, and our own impact on the ocean. It is an program built in stages that: 1) Establish high speed teleducation linkages with Eastern Shore of Virginia High Schools, for live interactive, classes (teleducation) for earth science teachers enabling them to remotely participate in University of Virginia classes in Oceanography (designed on a faculty development basis or acquire NSTA certification in Earth Science Education, as well as participation by seniors in the Accomack Schools; 2) Establish field experiences for teachers and selected students that involve travel to both the Virginia Coast Reserve Long Term Ecological Research (VCR/LTER) Center, UVA and the NOAA Beaufort, NC Laboratory to observe first- hand the science programs at those locations and participate in cutting edge coastal marine research efforts. These experiences will not only improve student understanding of the ocean-atmosphere biogeophysical system, but also encourage students to explore the sciences as a field of study and possible vocation. Advanced high school students and science teachers from Accomack County Public Schools participated in an experience involving field and laboratory methods employed in a NSF-sponsored study of the coupled natural-human dynamics on the Eastern Shore of Virginia over the past 500 years (NSF-Biocomplexity). Students and teachers worked with researchers of the VCR facility in Oyster, VA, collected sediment cores from Chesapeake Bay tributaries, and traveled to the Organic Geochemistry Laboratory at UVA, in Charlottesville, VA to prepare and analyze samples for isotopic and palynological information. In a first of its kind connectivity, in June/July, 2006, using high speed internet connections, a summer class in

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

Optimal Magnetic Field Shielding Method by Metallic Sheets in Wireless Power Transfer System

Directory of Open Access Journals (Sweden)

Feng Wen

2016-09-01

Full Text Available To meet the regulations established to limit human exposure to time-varying electromagnetic fields (EMFs such as the International Committee on Non-Ionizing Radiation Protection (ICNIRP guidelines, thin metallic sheets are often used to shield magnetic field leakage in high power applications of wireless power transfer (WPT systems based on magnetic field coupling. However, the metals in the vicinity of the WPT coils cause the decrease of self and mutual inductances and increase of effective series resistance; as such, the electric performance including transmission power and the efficiency of the system is affected. With the research objective of further investigating excellent shielding effectiveness associated with system performance, the utilization of the optimal magnetic field shielding method by metallic sheets in magnetic field coupling WPT is carried out in this paper. The circuit and 3D Finite Element Analysis (FEA models are combined to predict the magnetic field distribution and electrical performance. Simulation and experiment results show that the method is very effective by obtaining the largest possible coupling coefficient of the WPT coils within the allowable range and then reducing the value nearest to and no smaller than the critical coupling coefficient via geometric unbroken metallic sheets. The optimal magnetic field shielding method which considers the system efficiency, transmission power, transmission distance, and system size is also achieved using the analytic hierarchy process (AHP. The results can benefit WPT by helping to achieve efficient energy transfer and safe use in metal shielded equipment.

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…

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.

Earth System Modeling and Field Experiments in the Arctic-Boreal Zone - Report from a NASA Workshop

Science.gov (United States)

Sellers, Piers; Rienecker Michele; Randall, David; Frolking, Steve

2012-01-01

Early climate modeling studies predicted that the Arctic Ocean and surrounding circumpolar land masses would heat up earlier and faster than other parts of the planet as a result of greenhouse gas-induced climate change, augmented by the sea-ice albedo feedback effect. These predictions have been largely borne out by observations over the last thirty years. However, despite constant improvement, global climate models have greater difficulty in reproducing the current climate in the Arctic than elsewhere and the scatter between projections from different climate models is much larger in the Arctic than for other regions. Biogeochemical cycle (BGC) models indicate that the warming in the Arctic-Boreal Zone (ABZ) could lead to widespread thawing of the permafrost, along with massive releases of CO2 and CH4, and large-scale changes in the vegetation cover in the ABZ. However, the uncertainties associated with these BGC model predictions are even larger than those associated with the physical climate system models used to describe climate change. These deficiencies in climate and BGC models reflect, at least in part, an incomplete understanding of the Arctic climate system and can be related to inadequate observational data or analyses of existing data. A workshop was held at NASA/GSFC, May 22-24 2012, to assess the predictive capability of the models, prioritize the critical science questions; and make recommendations regarding new field experiments needed to improve model subcomponents. This presentation will summarize the findings and recommendations of the workshop, including the need for aircraft and flux tower measurements and extension of existing in-situ measurements to improve process modeling of both the physical climate and biogeochemical cycle systems. Studies should be directly linked to remote sensing investigations with a view to scaling up the improved process models to the Earth System Model scale. Data assimilation and observing system simulation

Equilibrium system analysis in a tokamak ignition experiment

International Nuclear Information System (INIS)

Carrera, R.; Weldon, W.F.; Woodson, H.H.

1989-10-01

The objective of the IGNITEX Project is to produce and control ignited plasmas for scientific study in the simplest and least expensive way possible. The original concept was proposed by both physics and engineering researchers along the following line of thought. Question: Is there any theoretically simple, compact and reliable way of achieving fusion ignition according to the results of the fusion research program for the last decades? Answer: Yes. An experiment to be carried out in an ohmically heated compact tokamak device with 20 T field on plasma axis. Question: Is there any practical way to carry out that experiment at low cost in the near term? Answer: Yes. Using a single-turn coil magnet system with homopolar power supplies

Equilibrium system analysis in a tokamak ignition experiment

Energy Technology Data Exchange (ETDEWEB)

Carrera, R.; Weldon, W.F.; Woodson, H.H.

1989-10-01

The objective of the IGNITEX Project is to produce and control ignited plasmas for scientific study in the simplest and least expensive way possible. The original concept was proposed by both physics and engineering researchers along the following line of thought. Question: Is there any theoretically simple, compact and reliable way of achieving fusion ignition according to the results of the fusion research program for the last decades Answer: Yes. An experiment to be carried out in an ohmically heated compact tokamak device with 20 T field on plasma axis. Question: Is there any practical way to carry out that experiment at low cost in the near term Answer: Yes. Using a single-turn coil magnet system with homopolar power supplies.

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.

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...

Experience on operational safety improvement of control and operation support systems

International Nuclear Information System (INIS)

Itoh, N.; Nakagawa, T.; Mano, K.

1988-01-01

Japanese nuclear industry started in 1956 and about 30 years have passed since that time. Through these years, we have made a lot of efforts and developments in the field of Control and Instrumentation (C and I) system. The above 30 years and following years can be divided into four major periods. The first one is the period of research, the second of domestic production, the third of improvement, and the fourth of advancement. Improvements of C and I system, which we have made in those periods have made a great contribution to enhancement of reliability, availability and operability of nuclear power plants. Fig. 1 shows TEPCO's nuclear power plant (BWR) construction experience and technical trend of C and I system in Japan. This paper is to introduce the efforts and operational experience on control and operation support systems

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.)

In pursuit of a science of agriculture: the role of statistics in field experiments.

Science.gov (United States)

Parolini, Giuditta

2015-09-01

Since the beginning of the twentieth century statistics has reshaped the experimental cultures of agricultural research taking part in the subtle dialectic between the epistemic and the material that is proper to experimental systems. This transformation has become especially relevant in field trials and the paper will examine the British agricultural institution, Rothamsted Experimental Station, where statistical methods nowadays popular in the planning and analysis of field experiments were developed in the 1920s. At Rothamsted statistics promoted randomisation over systematic arrangements, factorisation over one-question trials, and emphasised the importance of the experimental error in assessing field trials. These changes in methodology transformed also the material culture of agricultural science, and a new body, the Field Plots Committee, was created to manage the field research of the agricultural institution. Although successful, the vision of field experimentation proposed by the Rothamsted statisticians was not unproblematic. Experimental scientists closely linked to the farming community questioned it in favour of a field research that could be more easily understood by farmers. The clash between the two agendas reveals how the role attributed to statistics in field experimentation defined different pursuits of agricultural research, alternately conceived of as a scientists' science or as a farmers' science.

Modeling Users' Experiences with Interactive Systems

CERN Document Server

Karapanos, Evangelos

2013-01-01

Over the past decade the field of Human-Computer Interaction has evolved from the study of the usability of interactive products towards a more holistic understanding of how they may mediate desired human experiences.  This book identifies the notion of diversity in usersʼ experiences with interactive products and proposes methods and tools for modeling this along two levels: (a) interpersonal diversity in usersʽ responses to early conceptual designs, and (b) the dynamics of usersʼ experiences over time. The Repertory Grid Technique is proposed as an alternative to standardized psychometric scales for modeling interpersonal diversity in usersʼ responses to early concepts in the design process, and new Multi-Dimensional Scaling procedures are introduced for modeling such complex quantitative data. iScale, a tool for the retrospective assessment of usersʼ experiences over time is proposed as an alternative to longitudinal field studies, and a semi-automated technique for the analysis of the elicited exper...

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.

High magnetic field MRI system

International Nuclear Information System (INIS)

Maeda, Hideaki; Urata, Masami; Satoh, Kozo

1990-01-01

A high field superconducting magnet, 4-5 T in central magnetic field, is required for magnetic resonance spectroscopic imaging (MRSI) on 31 P, essential nuclei for energy metabolism of human body. This paper reviews superconducting magnets for high field MRSI systems. Examples of the cross-sectional image and the spectrum of living animals are shown in the paper. (author)

Experience representation in information systems

OpenAIRE

Kaczmarek, Jan

2014-01-01

This thesis looks into the ways subjective dimension of experience could be represented in artificial, non-biological systems, in particular information systems. The pivotal assumption is that experience as opposed to mainstream thinking in information science is not equal to knowledge, so that experience is a broader term which encapsulates both knowledge and subjective, affective component of experience, which so far has not been properly embraced by knowledge representation theories. This ...

Experience representation in information systems

OpenAIRE

Kaczmarek, Jan

2014-01-01

This thesis looks into the ways subjective dimension of experience could be represented in artificial, non-biological systems, in particular information systems. The pivotal assumption is that experience as opposed to mainstream thinking in information science is not equal to knowledge, so that experience is a broader term which encapsulates both knowledge and subjective, affective component of experience, which so far has not been properly embraced by knowledge representation theories. Th...

Field Mapping System for Solenoid Magnet

Science.gov (United States)

Park, K. H.; Jung, Y. K.; Kim, D. E.; Lee, H. G.; Park, S. J.; Chung, C. W.; Kang, B. K.

2007-01-01

A three-dimensional Hall probe mapping system for measuring the solenoid magnet of PLS photo-cathode RF e-gun has been developed. It can map the solenoid field either in Cartesian or in cylindrical coordinate system with a measurement reproducibility better than 5 × 10-5 T. The system has three axis motors: one for the azimuthal direction and the other two for the x and z direction. This architecture makes the measuring system simple in fabrication. The magnetic center was calculated using the measured axial component of magnetic field Bz in Cartesian coordinate system because the accuracy of magnetic axis measurement could be improved significantly by using Bz, instead of the radial component of magnetic field Br. This paper describes the measurement system and summarizes the measurement results for the solenoid magnetic of PLS photo-cathode RF e-gun.

Survey of Academic Field Experiences (SAFE): Trainees Report Harassment and Assault

Science.gov (United States)

Clancy, Kathryn B. H.; Nelson, Robin G.; Rutherford, Julienne N.; Hinde, Katie

2014-01-01

Little is known about the climate of the scientific fieldwork setting as it relates to gendered experiences, sexual harassment, and sexual assault. We conducted an internet-based survey of field scientists (N = 666) to characterize these experiences. Codes of conduct and sexual harassment policies were not regularly encountered by respondents, while harassment and assault were commonly experienced by respondents during trainee career stages. Women trainees were the primary targets; their perpetrators were predominantly senior to them professionally within the research team. Male trainees were more often targeted by their peers at the research site. Few respondents were aware of mechanisms to report incidents; most who did report were unsatisfied with the outcome. These findings suggest that policies emphasizing safety, inclusivity, and collegiality have the potential to improve field experiences of a diversity of researchers, especially during early career stages. These include better awareness of mechanisms for direct and oblique reporting of harassment and assault and, the implementation of productive response mechanisms when such behaviors are reported. Principal investigators are particularly well positioned to influence workplace culture at their field sites. PMID:25028932

Survey of academic field experiences (SAFE: trainees report harassment and assault.

Directory of Open Access Journals (Sweden)

Kathryn B H Clancy

Full Text Available Little is known about the climate of the scientific fieldwork setting as it relates to gendered experiences, sexual harassment, and sexual assault. We conducted an internet-based survey of field scientists (N = 666 to characterize these experiences. Codes of conduct and sexual harassment policies were not regularly encountered by respondents, while harassment and assault were commonly experienced by respondents during trainee career stages. Women trainees were the primary targets; their perpetrators were predominantly senior to them professionally within the research team. Male trainees were more often targeted by their peers at the research site. Few respondents were aware of mechanisms to report incidents; most who did report were unsatisfied with the outcome. These findings suggest that policies emphasizing safety, inclusivity, and collegiality have the potential to improve field experiences of a diversity of researchers, especially during early career stages. These include better awareness of mechanisms for direct and oblique reporting of harassment and assault and, the implementation of productive response mechanisms when such behaviors are reported. Principal investigators are particularly well positioned to influence workplace culture at their field sites.

Survey of academic field experiences (SAFE): trainees report harassment and assault.

Science.gov (United States)

Clancy, Kathryn B H; Nelson, Robin G; Rutherford, Julienne N; Hinde, Katie

2014-01-01

Little is known about the climate of the scientific fieldwork setting as it relates to gendered experiences, sexual harassment, and sexual assault. We conducted an internet-based survey of field scientists (N = 666) to characterize these experiences. Codes of conduct and sexual harassment policies were not regularly encountered by respondents, while harassment and assault were commonly experienced by respondents during trainee career stages. Women trainees were the primary targets; their perpetrators were predominantly senior to them professionally within the research team. Male trainees were more often targeted by their peers at the research site. Few respondents were aware of mechanisms to report incidents; most who did report were unsatisfied with the outcome. These findings suggest that policies emphasizing safety, inclusivity, and collegiality have the potential to improve field experiences of a diversity of researchers, especially during early career stages. These include better awareness of mechanisms for direct and oblique reporting of harassment and assault and, the implementation of productive response mechanisms when such behaviors are reported. Principal investigators are particularly well positioned to influence workplace culture at their field sites.

Experience-based Learning in Acadia National Park: a Successful, Long-running, Model Field Course

Science.gov (United States)

Connaughton, M.

2015-12-01

This two-week field course has been offered alternate summers since 2000 in Acadia National Park on Mount Desert Island, Maine and addresses the geological history, physical and biological oceanography and principles of community ecology applicable to terrestrial and/or marine communities of coastal Maine. The course is often transformative and deeply meaningful to the students, many of whom have limited travel experience. The essential components of experience-based learning are well represented in this class with multiple opportunities for abstract conceptualization, active experimentation, concrete hands-on experiences and reflective observation built into the course. Each day begins with a lecture introducing concepts, which are then made concrete though daily field trips (4-8 hours in duration) into the park that include rigorous hiking, some kayaking and one commercial nature cruise. Field trips include hands-on experience with lecture concepts, on-site lessons in field methods, and data collection for independent projects. Each field trip is tied to a specific independent project, which are generated by the instructor, but self-selected by the students. Every student is actively involved in data collection during each field trip, with one student in charge of the collection each day. Daily guided journaling in three parts (scientific, personal and creative) and evening discussions provide ample opportunity for the student to reflect on the scientific content of the course, examine their personal reactions to what they have experienced and to be creative, sharing prior experiences, prior learning and their personalities. The course includes two exams, each following a week of lecture and field experiences. Independent research projects include the production of a manuscript-formatted report complete with statistical analysis of the data and a literature-based discussion of the conclusions. The combination of experiential reinforcement of concepts, abundant

Upgrade of the synchronous data management system of the EAST poloidal field power supply

Energy Technology Data Exchange (ETDEWEB)

Zhu, Lili; Huang, Liansheng, E-mail: huangls@ipp.ac.cn; Fu, Peng; Gao, Ge; He, Shiying

2016-11-15

Highlights: • The upgraded synchronous data management system of EAST poloidal field power supply supports long-pulse data storage. • Slice storage mechanism on MDSplus has been adopted for quasi real-time data storage. • The state machine has been adopted for managing the system sequencer. • IEEE-1588 protocol via Ethernet for the synchronization of clock signal was detailed described. - Abstract: Poloidal field (PF) power supply is an important subsystem of the Experimental Advanced Superconducting Tokamak (EAST). The upgrade of the PF control system of EAST is a great improvement over the original data management system which could not meet the requirements necessary for experiments on synchronization, modularity and sampling rate. In order to better analyze the power operation performance, the Synchronization Data Management System (SDMS) needs to be upgraded as well. This upgrade is based on distributed data acquisition and an MDSPLUS database. It consists of three data acquisition nodes synchronized by an reference clock from the EAST central timing system that also provides the start trigger of the EAST pulse. After being processed by a signal conditioning unit, experimental signals are digitized and written into the database in MDSPLUS format. Multi-channel, multi-tasking and continuous data storage have been achieved by using multi-threading technology on a Linux operation system. The SDMS has been used on the server in PF control system for the entire 2015 EAST campaign. The SDMS has had good performance during experiments and convenient human-machine interface to satisfy the requirements of all the experiments.

Upgrade of the synchronous data management system of the EAST poloidal field power supply

International Nuclear Information System (INIS)

Zhu, Lili; Huang, Liansheng; Fu, Peng; Gao, Ge; He, Shiying

2016-01-01

Highlights: • The upgraded synchronous data management system of EAST poloidal field power supply supports long-pulse data storage. • Slice storage mechanism on MDSplus has been adopted for quasi real-time data storage. • The state machine has been adopted for managing the system sequencer. • IEEE-1588 protocol via Ethernet for the synchronization of clock signal was detailed described. - Abstract: Poloidal field (PF) power supply is an important subsystem of the Experimental Advanced Superconducting Tokamak (EAST). The upgrade of the PF control system of EAST is a great improvement over the original data management system which could not meet the requirements necessary for experiments on synchronization, modularity and sampling rate. In order to better analyze the power operation performance, the Synchronization Data Management System (SDMS) needs to be upgraded as well. This upgrade is based on distributed data acquisition and an MDSPLUS database. It consists of three data acquisition nodes synchronized by an reference clock from the EAST central timing system that also provides the start trigger of the EAST pulse. After being processed by a signal conditioning unit, experimental signals are digitized and written into the database in MDSPLUS format. Multi-channel, multi-tasking and continuous data storage have been achieved by using multi-threading technology on a Linux operation system. The SDMS has been used on the server in PF control system for the entire 2015 EAST campaign. The SDMS has had good performance during experiments and convenient human-machine interface to satisfy the requirements of all the experiments.

Junior physicians' workplace experiences in clinical fields in German-speaking Switzerland.

Science.gov (United States)

Buddeberg-Fischer, Barbara; Klaghofer, Richard; Abel, Thomas; Buddeberg, Claus

2005-01-08

To date, there have been several prospective cohort studies investigating the workplace experiences of junior physicians, but with limited focus on gender issues. The objective of the present study is to explore the workplace experiences of first-year residents according to gender, type of training hospital, and clinical field. Data reported are from the second assessment of the longitudinal Swiss physicians' career development study, begun in 2001. In 2003, 497 residents (54.7% females, 45.3% males) assessed their workplace conditions, social support at work, and effort-reward imbalance. There are few, but relevant, gender related differences in workplace experiences, with female physicians experiencing less mentoring and higher over-commitment, yet more positive social relationships at work. In a multivariate model, significant differences in some workplace variables with regard to type of training hospital and/or clinical field are found: workplace conditions are rated worse in type "A" hospitals (university and cantonal hospitals) than in type "B"/"C"/"D" hospitals (regional hospitals and highly specialised units), and in surgical fields than in internal medicine. In "A" hospitals mentoring is assessed as better, but positive social relationships as worse. Both scales are rated worse in surgical fields than in internal medicine. The effort-reward imbalance (ERI) is rated significantly higher (unfavourable) in "A" hospitals than in "B"/"C"/"D" hospitals, regardless of gender and clinical field. Significantly more subjects with an ERI quotient above 1 (which is unfavourable) work in "A" hospitals, and in surgical fields regardless of hospital type. Of the total sample, 81 subjects (16.3%), 41 males and 40 females, show an ERI quotient above 1. The greater the workload, the worse the rating of workplace conditions, effort-reward imbalance, and over-commitment. Institutional determinants are crucial factors for the workplace experiences and first career steps of

Tracking System : Suaineadh satellite experiment

OpenAIRE

Brengesjö, Carl; Selin, Martine

2011-01-01

The purpose of this bachelor thesis is to present a tracking system for the Suaineadh satellite experiment. The experiment is a part of the REXUS (Rocket EXperiments for University Students) program and the objective is to deploy a foldable web in space. The assignment of this thesis is to develop a tracking system to find the parts from the Suaineadh experiment that will land on Earth. It is important to find the parts and recover all the data that the experiment performed during the travel ...

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…

Magnetic-Field-Response Measurement-Acquisition System

Science.gov (United States)

Woodward, Stanley E.; Shams, Qamar A.; Fox, Robert L.; Taylor, Bryant D.

2006-01-01

A measurement-acquisition system uses magnetic fields to power sensors and to acquire measurements from sensors. The system alleviates many shortcomings of traditional measurement-acquisition systems, which include a finite number of measurement channels, weight penalty associated with wires, use limited to a single type of measurement, wire degradation due to wear or chemical decay, and the logistics needed to add new sensors. Eliminating wiring for acquiring measurements can alleviate potential hazards associated with wires, such as damaged wires becoming ignition sources due to arcing. The sensors are designed as electrically passive inductive-capacitive or passive inductive-capacitive-resistive circuits that produce magnetic-field-responses. One or more electrical parameters (inductance, capacitance, and resistance) of each sensor can be variable and corresponds to a measured physical state of interest. The magnetic-field- response attributes (frequency, amplitude, and bandwidth) of the inductor correspond to the states of physical properties for which each sensor measures. For each sensor, the measurement-acquisition system produces a series of increasing magnetic-field harmonics within a frequency range dedicated to that sensor. For each harmonic, an antenna electrically coupled to an oscillating current (the frequency of which is that of the harmonic) produces an oscillating magnetic field. Faraday induction via the harmonic magnetic fields produces an electromotive force and therefore a current in the sensor. Once electrically active, the sensor produces its own harmonic magnetic field as the inductor stores and releases magnetic energy. The antenna of the measurement- acquisition system is switched from a transmitting to a receiving mode to acquire the magnetic-field response of the sensor. The rectified amplitude of the received response is compared to previous responses to prior transmitted harmonics, to ascertain if the measurement system has detected a

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

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…

A magnet system for HEP experiments

CERN Document Server

Gaddi, A

2012-01-01

This chapter describes the sequence of steps that lead to the design of a magnet system for modern HEP detectors. We start looking to the main types of magnets used in HEP experiments, along with some basic formulae to set the main parameters, such as ampere-turns, impedance and stored energy. A section is dedicated to the description of the iron yoke, with emphasis on magnet-detector integration and assembly, steel characteristics, stray field issues and alternative design. In the second part of the chapter we start looking at a brief history of superconducting magnets and a comparison between warm and superconducting ones. Following that, we describe the commonly used superconducting cables, the conductor design and technology and the winding techniques. A section of the chapter is dedicated to the cryogenic design, vacuum insulation and other ancillary systems. We also describe the power circuit, with the power supply unit, the current leads, the current measurement devices and other instruments and safety...

Development and performance test of a system available for generating multiple extreme conditions for neutron scattering experiments

International Nuclear Information System (INIS)

Kawano, Shinji; Fukui, Susumu; Moriai, Atsushi; Ohtomo, Akitoshi; Ichimura, Shigeki; Onodera, Akifumi; Amita, F.; Katano, Susumu

1998-01-01

We have developed unique system available for controlling sample environment during the neutron scattering experiments. The system can simultaneously generate triple extreme conditions of low temperature, high magnetic field and high pressure. The system consists of: (i) a liquid-helium cryostat variable for sample temperature from 1.7 K to 200 K, (ii) a superconducting magnet providing a vertical field up to ±5 T with an antisymmetric split-coil geometry for polarized-beam experiments, and (iii) a non-magnetic piston-cylinder high-pressure cell designed with the aim of generating hydrostatic pressure up to 2.5 GPa. In the presentation, we will report the outline of the system and some results of performance tests at KURRI and JRR-3M of JAERI. (author)

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.

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…

Development of digital device based work verification system for cooperation between main control room operators and field workers in nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

Lee, Seung Min, E-mail: jewellee@kaeri.re.kr [Korea Atomic Energy Research Institute, 305-353, 989-111 Daedeok-daero, Yuseong-gu, Daejeon (Korea, Republic of); Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Lee, Hyun Chul, E-mail: leehc@kaeri.re.kr [Korea Atomic Energy Research Institute, 305-353, 989-111 Daedeok-daero, Yuseong-gu, Daejeon (Korea, Republic of); Ha, Jun Su, E-mail: junsu.ha@kustar.ac.ae [Department of Nuclear Engineering, Khalifa University of Science Technology and Research, Abu Dhabi P.O. Box 127788 (United Arab Emirates); Seong, Poong Hyun, E-mail: phseong@kaist.ac.kr [Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)

2016-10-15

Highlights: • A digital device-based work verification and cooperation support system was developed. • Requirements were derived by interviewing field operators having experiences with mobile-based work support systems. • The usability of the proposed system was validated by conducting questionnaire surveys. • The proposed system will be useful if the manual or the set of guidelines is well constructed. - Abstract: Digital technologies have been applied in the nuclear field to check task results, monitor events and accidents, and transmit/receive data. The results of using digital devices have proven that these devices can provide high accuracy and convenience for workers, allowing them to obtain obvious positive effects by reducing their workloads. In this study, as one step forward, a digital device-based cooperation support system, the nuclear cooperation support and mobile documentation system (Nu-COSMOS), is proposed to support communication between main control room (MCR) operators and field workers by verifying field workers’ work results in nuclear power plants (NPPs). The proposed system consists of a mobile based information storage system to support field workers by providing various functions to make workers more trusted by MCR operators; also to improve the efficiency of meeting, and a large screen based information sharing system supports meetings by allowing both sides to share one medium. The usability of this system was estimated by interviewing field operators working in nuclear power plants and experts who have experience working as operators. A survey to estimate the usability of the suggested system and the suitability of the functions of the system for field working was conducted for 35 subjects who have experience in field works or with support system development-related research. The usability test was conducted using the system usability scale (SUS), which is widely used in industrial usability evaluation. Using questionnaires

Development of digital device based work verification system for cooperation between main control room operators and field workers in nuclear power plants

International Nuclear Information System (INIS)

Lee, Seung Min; Lee, Hyun Chul; Ha, Jun Su; Seong, Poong Hyun

2016-01-01

Highlights: • A digital device-based work verification and cooperation support system was developed. • Requirements were derived by interviewing field operators having experiences with mobile-based work support systems. • The usability of the proposed system was validated by conducting questionnaire surveys. • The proposed system will be useful if the manual or the set of guidelines is well constructed. - Abstract: Digital technologies have been applied in the nuclear field to check task results, monitor events and accidents, and transmit/receive data. The results of using digital devices have proven that these devices can provide high accuracy and convenience for workers, allowing them to obtain obvious positive effects by reducing their workloads. In this study, as one step forward, a digital device-based cooperation support system, the nuclear cooperation support and mobile documentation system (Nu-COSMOS), is proposed to support communication between main control room (MCR) operators and field workers by verifying field workers’ work results in nuclear power plants (NPPs). The proposed system consists of a mobile based information storage system to support field workers by providing various functions to make workers more trusted by MCR operators; also to improve the efficiency of meeting, and a large screen based information sharing system supports meetings by allowing both sides to share one medium. The usability of this system was estimated by interviewing field operators working in nuclear power plants and experts who have experience working as operators. A survey to estimate the usability of the suggested system and the suitability of the functions of the system for field working was conducted for 35 subjects who have experience in field works or with support system development-related research. The usability test was conducted using the system usability scale (SUS), which is widely used in industrial usability evaluation. Using questionnaires

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

Proton and deuterium NMR experiments in zero field. [Perdeuterated p-demethoxybenzene, perdeuterated malonic acid, diethyl terephthalate-d4, nonadecane-2,2'-D2, sodium propionate-D2

Energy Technology Data Exchange (ETDEWEB)

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 /sup 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.

Field experience with the FAA's Web-based medical certification system "AMCS/DIWS". Federal Aviation Administration.

Science.gov (United States)

Angelici, Arnold A; Mohler, Stanley R

2002-04-01

The October 1, 1999, introduction in the U.S. of a Web-based medical certification process for civil aircrew opened a new era within civil aviation. The Federal Aviation Administration's (FAA) Aeromedical Certification System/Document Imaging Workflow System (AMCS/DIWS) has imposed certain new requirements on the designated Aviation Medical Examiners (AMEs), including the use of Internet systems and procedures. A number of AMEs elected to discontinue their work as the classic medical certification processes were replaced. The authors document their personal experience with respect to the new system, and cite the overall advantages that modernized medical certification procedures bring. These advantages include far fewer "mistakes of omission" by AMEs, more timely receipt by the FAA of aircrew certification data, and a developing master aircrew database for analytic studies.

A large scale field experiment in the Amazon Basin (Lambada/Bateristca)

Energy Technology Data Exchange (ETDEWEB)

Dolman, A.J.; Kabat, P.; Gash, J.H.C.; Noilhan, J.; Jochum, A.M.; Nobre, C. [Winand Staring Centre, Wageningen (Netherlands)

1994-12-31

A description is given of a large scale field experiment planned in the Amazon Basin, aiming to assess the large scale balances of energy, water and CO{sub 2}. The background for this experiment, the embedding in global change programmes of IGBP/BAHC and WCRP/GEWEX is described. A proposal by four European groups aimed at designing the experiment with the help of mesoscale models is described and a possible European input to this experiment is suggested. 24 refs., 1 app.

The topology of integrable systems with incomplete fields

International Nuclear Information System (INIS)

Aleshkin, K R

2014-01-01

Liouville's theorem holds for Hamiltonian systems with complete Hamiltonian fields which possess a complete involutive system of first integrals; such systems are called Liouville-integrable. In this paper integrable systems with incomplete Hamiltonian fields are investigated. It is shown that Liouville's theorem remains valid in the case of a single incomplete field, while if the number of incomplete fields is greater, a certain analogue of the theorem holds. An integrable system on the algebra sl(3) is taken as an example. Bibliography: 11 titles

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…

Study on the system development for evaluating long-term alteration of hydraulic field in Near Field. 3

International Nuclear Information System (INIS)

Okutu, Kazuo; Morikawa, Seiji; Taguchi, Katsunori

2004-02-01

For the high performance evaluation of reliability of TRU waste repository, the system development for evaluating long-term alteration in consideration of the changes action of barrier materials of hydraulic field in Near Fields is required. In this research, the system development for evaluating the long-term alteration of hydraulic field in near field was examined. The 'Evidential Support logic' for ensuring the long-term stability of the repository was developed and evaluated. Furthermore, the developed chemical/mechanical alteration action analysis system was verified and improved. The system was coupled for the long-term alteration evaluation analysis. The research results of this year are shown below. 1) A logic tree was constructed for the purpose of supporting the high performance evaluation of reliability of a TRU waste repository. The thesis that the long term safety of the TRU waste repository is preserved was ramified into subsidiary theses until all the final theses were supported by objective evidence. The probability of the subsidiary thesis supporting the upper thesis was established by interviewing specialists. The reliability of the thesis was evaluated by applying present knowledge. Furthermore, the sensitivity of the reliability of the highest thesis to increasing reliability of evidence was investigated. Appropriate targets for experiment and analysis were presented based on the sensitivity of evidence. 2) The object of the hydraulic - chemical analysis was determined from the above-mentioned logic tree. The analysis system was improved to perform the 2D analysis. A user interface was developed to simplify the setting of analysis conditions. The system was demonstrated by comparing the results with the experimental results. Furthermore, the system was applied to the near field problem to fix the condition that the safety of the TRU waste repository is preserved. 3) Both the model of bentonite material and the model of cement material were

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.)

Using Teleducation and Field Experiences to further the Understanding of Coastal Environments

Science.gov (United States)

Macko, S. A.; Szuba, T. A.; Shugart, H.

2007-05-01

This project is an outreach and education program with a partner in the K-12 schools at Accomack County on the Eastern Shore of Virginia. It endeavors to build a community knowledgeable of the importance the ocean plays daily in our lives, and our own impact on the ocean. It is an program built in stages that: 1) Establish high speed live interactive classes (teleducation) linkages with the Eastern Shore High Schools with earth science teachers enabling them to remotely participate in University of Virginia classes in Oceanography (designed on a faculty development basis or acquire NSTA certification in Earth Science Education, as well as participation by seniors in the Accomack Schools; 2) Establish field experiences for teachers and selected students that involve travel to both the Virginia Coast Reserve Long Term Ecological Research (VCR/LTER) Center, UVA to observe first- hand the science programs at those locations and participate in cutting edge coastal marine research efforts. These experiences improve student understanding of the ocean-atmosphere biogeophysical system and encourage students to explore the sciences as a field of study and possible vocation. Advanced high school students and science teachers from Accomack County Public Schools participated in an experience involving field and laboratory methods employed in a NSF-sponsored study of the coupled natural-human dynamics on the Eastern Shore of Virginia over the past 500 years (NSF-Biocomplexity). Students and teachers worked with researchers of the VCR facility in Oyster, VA, collected sediment cores from Chesapeake Bay tributaries, and traveled to the Organic Geochemistry Laboratory at UVA, in Charlottesville, VA to prepare and analyze samples for isotopic and palynological information. In a first of its kind connectivity, in June/July, 2006, using high speed internet connections, a summer class in Oceanography was live, interactively broadcast (teleducation) from UVA to Arcadia High School on

Experience on HTCondor batch system for HEP and other research fields at KISTI-GSDC

Science.gov (United States)

Ahn, S. U.; Jaikar, A.; Kong, B.; Yeo, I.; Bae, S.; Kim, J.

2017-10-01

Global Science experimental Data hub Center (GSDC) at Korea Institute of Science and Technology Information (KISTI) located at Daejeon in South Korea is the unique datacenter in the country which helps with its computing resources fundamental research fields dealing with the large-scale of data. For historical reason, it has run Torque batch system while recently it starts running HTCondor for new systems. Having different kinds of batch systems implies inefficiency in terms of resource management and utilization. We conducted a research on resource management with HTCondor for several user scenarios corresponding to the user environments that currently GSDC supports. A recent research on the resource usage patterns at GSDC is considered in this research to build the possible user scenarios. Checkpointing and Super-Collector model of HTCondor give us more efficient and flexible way to manage resources and Grid Gate provided by HTCondor helps to interface with the Grid environment. In this paper, the overview on the essential features of HTCondor exploited in this work is described and the practical examples for HTCondor cluster configuration in our cases are presented.

Design and construction of a superconducting magnet system for the absolute ampere experiment

International Nuclear Information System (INIS)

Chen, W.Y.; Olsen, P.T.; Phillips, W.D.; Purcell, J.R.; Williams, E.R.

1982-01-01

A complete superconducting magnet system designed by General Atomic Company for the National Bureau of Standards is described. It is to be utilized in the absolute ampere experiment. Key features of the magnet system are high precision, low LHe consumption, low eddy current effects, and modular construction. The system requirements are specified and the set-up illustrated schematically. Design description includes superconducting coils, (illustrated), coil dewar, field analysis, and three stages of fabrication

The Information Science Experiment System - The computer for science experiments in space

Science.gov (United States)

Foudriat, Edwin C.; Husson, Charles

1989-01-01

The concept of the Information Science Experiment System (ISES), potential experiments, and system requirements are reviewed. The ISES is conceived as a computer resource in space whose aim is to assist computer, earth, and space science experiments, to develop and demonstrate new information processing concepts, and to provide an experiment base for developing new information technology for use in space systems. The discussion covers system hardware and architecture, operating system software, the user interface, and the ground communication link.

Pulsed-coil magnet systems for applying uniform 10-30 T fields to centimeter-scale targets on Sandia's Z facility.

Science.gov (United States)

Rovang, D C; Lamppa, D C; Cuneo, M E; Owen, A C; McKenney, J; Johnson, D W; Radovich, S; Kaye, R J; McBride, R D; Alexander, C S; Awe, T J; Slutz, S A; Sefkow, A B; Haill, T A; Jones, P A; Argo, J W; Dalton, D G; Robertson, G K; Waisman, E M; Sinars, D B; Meissner, J; Milhous, M; Nguyen, D N; Mielke, C H

2014-12-01

Sandia has successfully integrated the capability to apply uniform, high magnetic fields (10-30 T) to high energy density experiments on the Z facility. This system uses an 8-mF, 15-kV capacitor bank to drive large-bore (5 cm diameter), high-inductance (1-3 mH) multi-turn, multi-layer electromagnets that slowly magnetize the conductive targets used on Z over several milliseconds (time to peak field of 2-7 ms). This system was commissioned in February 2013 and has been used successfully to magnetize more than 30 experiments up to 10 T that have produced exciting and surprising physics results. These experiments used split-magnet topologies to maintain diagnostic lines of sight to the target. We describe the design, integration, and operation of the pulsed coil system into the challenging and harsh environment of the Z Machine. We also describe our plans and designs for achieving fields up to 20 T with a reduced-gap split-magnet configuration, and up to 30 T with a solid magnet configuration in pursuit of the Magnetized Liner Inertial Fusion concept.

A case study of intended versus actual experience of adaptivity in a tangible storytelling system

NARCIS (Netherlands)

Tanenbaum, K.; Hatala, M.; Tanenbaum, J.; Wakkary, R.L.; Antle, A.N.

2014-01-01

This article presents a case study of an adaptive, tangible storytelling system called "The Reading Glove". The research addresses a gap in the field of adaptivity for ubiquitous systems by taking a critical look at the notion of "adaptivity" and how users experience it. The Reading Glove is an

Hot Cathode Biasing Experiment in Compact Helical System

Energy Technology Data Exchange (ETDEWEB)

Takahashi, H.; Utoh, H.; Kitajima, S.; Isobe, M.; Suzuki, C.; Takeuchi, M.; Ikeda, R.; Tanaka, Y.; Yokoyama, M.; Toi, K.; Okamura, S.; Sasao, M.

2005-07-01

One of the H mode characteristics is a sudden formation of a radial electric field at LH transition. To date, H mode was widely observed in various tokamaks [1-3] and stellarator devices [4, 5], and the importance of the radial electric field has been shown in both experiments and in theory. However, it is difficult to investigate the behaviour of a radial electric field in detail at LH transition induced by NBI heating because the radial electric field is self-organised and changes suddenly. Electrode bias experiments are methods for active control of the radial electric field. The electrode bias experiment has the advantage of the ability to control the radial electric field externally by controlling the electrode voltage and/or the electrode current and to estimate the driving force from the electrode current. The neoclassical theory indicates the criterion of LH transition from the viewpoint of the ion viscosity. In this theory, the ion viscosity has local maxima against the rotation velocity [6-8]. When the driving force in the poloidal direction exceeds a critical value, the poloidal rotation velocity increases rapidly and the plasma undergoes a transition to the H mode. This means that the LH transition mechanism is a bifurcation phenomenon due to the existence of local maxima in the ion viscosity. Here, we carried out the electrode biasing experiment in TU-Heliac and CHS to investigate the effect of ripple structure on ion viscosity and to clarify the role of ion viscosity in triggering the transition from the degraded state to enhanced confinement. (Author)

Cost Optimal System Identification Experiment Design

DEFF Research Database (Denmark)

Kirkegaard, Poul Henning

A structural system identification experiment design method is formulated in the light of decision theory, structural reliability theory and optimization theory. The experiment design is based on a preposterior analysis, well-known from the classical decision theory. I.e. the decisions concerning...... reflecting the cost of the experiment and the value of obtained additional information. An example concerning design of an experiment for parametric identification of a single degree of freedom structural system shows the applicability of the experiment design method....... the experiment design are not based on obtained experimental data. Instead the decisions are based on the expected experimental data assumed to be obtained from the measurements, estimated based on prior information and engineering judgement. The design method provides a system identification experiment design...

DEALS magnet concept and its applcations to high density, high field tokamak systems

International Nuclear Information System (INIS)

Hsieh, S.Y.; Powell, J.; Lehner, J.; Bezler, P.; Laverick, C.; Finkelman, M.; Brown, T.; Bundy, J.

1977-01-01

The goal of the DEALS program is to develop a demountable TF magnet system concept that will reduce construction and life cycle costs, enhance the accessibility of components inside the coil system, and increase the chances for being able to use large high-field magnet systems in post TFTR reactor experiments. These experiments are projected to occur during the mid 1980's, with conceptual designs beginning in two or three years. A number of recent studies have highlighted the need for Tokamak fusion reactor systems with reasonable down time for maintenance and repair and realistic operating capacity factors, as well as the need for smaller, lower cost reactors. Two scoping studies were carried out of recent Tokamak system concepts incorporating conventionally wound coils to assess the possibilities of using demountable coils of rectangular section with an active support system and a third more intensive study using a passive support with slight movement of the joints. These studies are described briefly

Technical results of Y-12/IAEA field trial of remote monitoring system

International Nuclear Information System (INIS)

Corbell, B.H.; Whitaker, J.M.; Welch, J.

1997-01-01

A Remote Monitoring System (RMS) field trial has been conducted with the International Atomic Energy Agency (IAEA) on highly enriched uranium materials in a vault at the Oak Ridge Y-12 Plant. The RMS included a variety of Sandia, Oak Ridge, and Aquila sensor technologies which provide containment seals, video monitoring, radiation asset measurements, and container identification data to the on-site DAS (Data Acquisition System) by way of radio-frequency and Echelon LonWorks networks. The accumulated safeguards information was transmitted to the IAEA via satellite (COMSAT/RSI) and international telephone lines. The technologies tested in the remote monitoring environment are the RadCouple, RadSiP, and SmartShelf sensors from the ORSENS (Oak Ridge Sensors for Enhancing Nuclear Safeguards) technologies; the AIMS (Authenticated Item Monitoring System) motion sensor (AMS), AIMS fiber-optic seal (AFOS), ICAM (Image Compression and Authentication Module) video surveillance system, DAS (Data Acquisition System), and DIRS (Data and Image Review Station) from Sandia; and the AssetLAN identification tag, VACOSS-S seal, and Gemini digital surveillance system from Aquila. The field trial was conducted from October 1996 through May 1997. Tests were conducted during the monthly IAEA Interim Inventory Verification (IIV) inspections for evaluation of the equipment. Experience gained through the field trials will allow the technologies to be applied to various monitoring scenarios

Wide-Field Imaging Telescope-0 (WIT0) with automatic observing system

Science.gov (United States)

Ji, Tae-Geun; Byeon, Seoyeon; Lee, Hye-In; Park, Woojin; Lee, Sang-Yun; Hwang, Sungyong; Choi, Changsu; Gibson, Coyne Andrew; Kuehne, John W.; Prochaska, Travis; Marshall, Jennifer L.; Im, Myungshin; Pak, Soojong

2018-01-01

We introduce Wide-Field Imaging Telescope-0 (WIT0), with an automatic observing system. It is developed for monitoring the variabilities of many sources at a time, e.g. young stellar objects and active galactic nuclei. It can also find the locations of transient sources such as a supernova or gamma-ray bursts. In 2017 February, we installed the wide-field 10-inch telescope (Takahashi CCA-250) as a piggyback system on the 30-inch telescope at the McDonald Observatory in Texas, US. The 10-inch telescope has a 2.35 × 2.35 deg field-of-view with a 4k × 4k CCD Camera (FLI ML16803). To improve the observational efficiency of the system, we developed a new automatic observing software, KAOS30 (KHU Automatic Observing Software for McDonald 30-inch telescope), which was developed by Visual C++ on the basis of a windows operating system. The software consists of four control packages: the Telescope Control Package (TCP), the Data Acquisition Package (DAP), the Auto Focus Package (AFP), and the Script Mode Package (SMP). Since it also supports the instruments that are using the ASCOM driver, the additional hardware installations become quite simplified. We commissioned KAOS30 in 2017 August and are in the process of testing. Based on the WIT0 experiences, we will extend KAOS30 to control multiple telescopes in future projects.

TWRS system drawings and field verification

International Nuclear Information System (INIS)

Shepard, D.G.

1995-01-01

The Configuration Management Program combines the TWRS Labeling and O and M drawing and drawing verification programs. The combined program will produce system drawings for systems that are normally operated or have maintenance performed on the system, label individual pieces of equipment for proper identification, even if system drawings are not warranted, and perform verification of drawings that are identified as essential in Tank Farm Essential Drawing Plans. During fiscal year 1994, work was begun to label Tank Farm components and provide user friendly system based drawings for Tank Waste Remediation System (TWRS) operations and maintenance. During the first half of fiscal 1995, the field verification program continued to convert TWRS drawings into CAD format and verify the accuracy based on visual inspections. During the remainder of fiscal year 1995 these efforts will be combined into a single program providing system based drawings and field verification of TWRS equipment and facilities. This combined program for TWRS will include all active systems for tank farms. Operations will determine the extent of drawing and labeling requirements for single shell tanks, i.e. the electrical distribution, HVAC, leak detection, and the radiation monitoring system. The tasks required to meet these objectives, include the following: identify system boundaries or scope for drawing being verified; label equipment/components in the process systems with a unique Equipment Identification Number (EIN) per the TWRS Data Standard; develop system drawings that are coordinated by ''smart'' drawing numbers and/or drawing references as identified on H-14-020000; develop a Master Equipment List (MEL) multi-user data base application which will contain key information about equipment identified in the field; and field verify and release TWRS Operation and Maintenance (O and M) drawings

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

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.

U.S. Army RDECOM-ARDEC's results of the TG-53 experiment and field test

Science.gov (United States)

Desai, Sachi V.; Morcos, Amir

2009-05-01

Herein is described the U.S. Army RDECOM-ARDEC's purpose and series of activities conducted at the 2008 NATO SET-093 TG-53 experiment and field test. The overall purpose of the field test as stated by SET-093 panel was to provide a baseline test capable of providing relevant scenarios and data regarding a variety of impulsive generated acoustic events. As organized, the field experiment also allowed the room o study sensor interoperability across multiple platforms and multi-national users via the spider communication framework/reporting structure. This multinational network maintained by the host ETBS with a standardized messaging format with specific goals for each participating organization. ARDEC's role and purpose for the test was to provide situational awareness via the Spider and associated messaging format to the ETBS command center while continuing to gather unique acoustic data from various vantage points. ARDEC had several deliverables for the TG-53 field experiment derived from the mission and spirit of the field test. The most relevant deliverable was to demonstrate sensor interoperability via the Spider network and provide situational awareness by describing the said mortar/artillery events. The second purpose revolved around a relevant environment algorithm validation of the muzzle blast discrimination for future UGS transition in particular the UTAMS II. The algorithm validation information remained internal to the specific data acquisition system and not broadcasted out on the Spider network. The TG-53 field experiments provided the added opportunity to further test and refine the algorithm based on the discrete wavelet transform (DWT) and multiresolution analysis. These techniques are used to classify and reliably discriminates between launch and impact artillery and/or mortar events via acoustic signals produced during detonation. Distinct characteristics are found within the acoustic signatures since impact events emphasize concussive and

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…

Gravitation Theory: Empirical Status from Solar System Experiments: All observations to date are consistent with Einstein's general relativity theory of gravity.

Science.gov (United States)

Nordtvedt, K L

1972-12-15

I have reviewed the historical and contemporary experiments that guide us in choosing a post-Newtonian, relativistic gravitational theory. The foundation experiments essentially constrain gravitation theory to be a metric theory in which matter couples solely to one gravitational field, the metric field, although other cosmological gravitational fields may exist. The metric field for any metric theory can be specified (for the solar system, for our present purposes) by a series of potential terms with several parameters. A variety of experiments specify (or put limits on) the numerical values of the seven parameters in the post-Newtonian metric field, and other such experiments have been planned. The empirical results, to date, yield values of the parameters that are consistent with the predictions of Einstein's general relativity.

Investigation of fracture-matrix interaction: Preliminary experiments in a simple system

International Nuclear Information System (INIS)

Foltz, S.D.

1992-01-01

Paramount to the modeling of unsaturated flow and transport through fractured porous media is a clear understanding of the processes controlling fracture-matrix interaction. As a first step toward such an understanding, two preliminary experiments have been performed to investigate the influence of matrix imbibition on water percolation through unsaturated fractures in the plane normal to the fracture. Test systems consisted of thin slabs of either tuff or an analog material cut by a single vertical fracture into which a constant fluid flux was introduced. Transient moisture content and solute concentration fields were imaged by means of x-ray absorption. Flow fields associated with the two different media were significantly different owing to differences in material properties relative to the imposed flux. Richards' equation was found to be a valid means of modeling the imbibition of water into the tuff matrix from a saturated fracture for the current experiment

Magnetic field measuring system for remapping the ORIC magnetic field

International Nuclear Information System (INIS)

Mosko, S.W.; Hudson, E.D.; Lord, R.S.; Hensley, D.C.; Biggerstaff, J.A.

1977-01-01

The Holifield Heavy Ion Research Facility will integrate a new 25 MV tandem electrostatic acccelerator into the existing cyclotron laboratory which includes the Oak Ridge Isochronous Cyclotron (ORIC). Computations of ion paths for beam injection from the new tandem into ORIC require field mapping in the regions traversed by the beam. Additional field data is also desired for the higher levels (approx.19 kG) now used for most heavy ion beams. The magnetic field measurement system uses 39 flip coil/current integrator sets with computer controlled data scanning. The coils are spaced radially at 1 inch intervals in an arm which can be rotated azimuthally in 2 degree increments. The entire flip coil assembly can be shifted to larger radii to measure fields beyond the pole boundary. Temperature stabilization of electronic circuitry permits a measurement resolution of +-1 gauss over a dynamic range of +-25,000 gauss. The system will process a scan of 8000 points in about one hour

Turbulent Dynamo Amplification of Magnetic Fields in Laser-Produced Plasmas: Simulations and Experiments

Science.gov (United States)

Tzeferacos, P.; Rigby, A.; Bott, A.; Bell, A.; Bingham, R.; Casner, A.; Cattaneo, F.; Churazov, E.; Forest, C.; Katz, J.; Koenig, M.; Li, C.-K.; Meinecke, J.; Petrasso, R.; Park, H.-S.; Remington, B.; Ross, J.; Ryutov, D.; Ryu, D.; Reville, B.; Miniati, F.; Schekochihin, A.; Froula, D.; Lamb, D.; Gregori, G.

2017-10-01

The universe is permeated by magnetic fields, with strengths ranging from a femtogauss in the voids between the filaments of galaxy clusters to several teragauss in black holes and neutron stars. The standard model for cosmological magnetic fields is the nonlinear amplification of seed fields via turbulent dynamo. We have conceived experiments to demonstrate and study the turbulent dynamo mechanism in the laboratory. Here, we describe the design of these experiments through large-scale 3D FLASH simulations on the Mira supercomputer at ANL, and the laser-driven experiments we conducted with the OMEGA laser at LLE. Our results indicate that turbulence is capable of rapidly amplifying seed fields to near equipartition with the turbulent fluid motions. This work was supported in part from the ERC (FP7/2007-2013, No. 256973 and 247039), and the U.S. DOE, Contract No. B591485 to LLNL, FWP 57789 to ANL, Grant No. DE-NA0002724 and DE-SC0016566 to the University of Chicago, and DE-AC02-06CH11357 to ANL.

The Role of Laboratory Experiments in the Validation of Field Data

DEFF Research Database (Denmark)

Mouneyrac, Catherine; Lagarde, Fabienne; Chatel, Amelie

2017-01-01

The ubiquitous presence and persistency of microplastics (MPs) in aquatic environments are of particular concern, since they constitute a potential threat to marine organisms and ecosystems. However, evaluating this threat and the impacts of MP on aquatic organisms is challenging. MPs form a very...... and to what degree these complexities are addressed in the current literature, to: (1) evaluate how well laboratory studies, investigated so far, represent environmentally relevant processes and scenarios and (2) suggest directions for future research The Role of Laboratory Experiments in the Validation...... of Field Data | Request PDF. Available from: https://www.researchgate.net/publication/310360438_The_Role_of_Laboratory_Experiments_in_the_Validation_of_Field_Data [accessed Jan 15 2018]....

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.

The COSY control system, a distributed realtime operating system: First practical experience at the COSY-injector

International Nuclear Information System (INIS)

Stephan, M.; Hacker, U.; Henn, K.; Richert, A.; Sobotta, K.; Weinert, A.

1991-01-01

The COSY control system is hierarchically organized with distributed intelligence and autonomous processing units for dedicated components. Data communication is performed via LAN and over a fieldbus. The hostsystems are UNIX-based, whereas the field-controllers are running a modular realtime operating-system RT/OS which has been developed at KFA. The computer-hardware consists of RISC mini computers, VME-computers in the field and G64 equipment-control-module in geographical expansion of the controller by a fieldbus based on the PDV-standard. The man-machine interface consists of X-window based work stations. On top of X-window a graphical user interface based on object oriented methods is used. A distributed realtime data base allows access to the accelerator state from every workstation. A special highlevel language debugger hosted on the UNIX based workstation and connected over LAN to the VME targets will be used. Together with the software development system for UNIX applications an uniform view of the system appears to the programmer. First practical experience at the COSY injector is presented

Field-based systems and advanced diagnostics

International Nuclear Information System (INIS)

Eryurek, E.

1998-01-01

Detection and characterization of anomalies in an industrial plant provide improved plant availability and plant efficiency thus yielding increased economic efficiency. Traditionally, detection of process anomalies is done at a high-level control system through various signal validation methods. These signal validation techniques rely on data from transmitters, which measure related process variables. Correlating these signals and deducing anomalies often is a very time consuming and a difficult task. Delays in detecting these anomalies can be costly during plant operation. Conventional centralized approaches also suffer from their dependence on detailed mathematical models of the processes. Smart field devices have the advantage of providing the necessary information directly to the control system as anomalies develop during operation of the processes enabling operators to take necessary steps to either prevent an unnecessary shut down before the problem becomes serious or schedule maintenance on the problematic loop. Fisher-Rosemount's PlantWeb TM architecture addresses 'Enhanced Measurement, Advanced Diagnostics and Control in the Field'. PlantWeb TM builds open process management systems by networking intelligent field devices, scalable control and systems platforms, and integrated modular software. A description of PlantWeb TM and how it improves various process conditions and reduces operating cost of a plant as well as a high level description of 'Enhanced Measurement, Advanced Diagnostics and Control in the Field', will be provided in this paper. PlantWeb TM is the trademark for Fisher-Rosemount's new field-based architecture that uses emerging technologies to utilize the power of intelligent field devices and deliver critical process and equipment information to improve plant performance. (author)

Proton polarizing system with Ar-ion laser for p-vector-RI scattering experiments

International Nuclear Information System (INIS)

Wakui, T.; Hatano, M.; Sakai, H.; Uesaka, T.; Tamii, A.

2005-01-01

A proton polarizing system for use in scattering experiments with radioactive isotope beams is described. Protons in a naphthalene crystal doped with pentacene are polarized in a magnetic field of 0.3T at 100K by transferring a large population difference among the photo-excited triplet states of pentacene to the hydrogen nuclei. An Ar-ion laser, which demands minimal maintenance during scattering experiments, is employed to excite the pentacene molecules. A proton polarization of 37% is obtained

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.

Ultra-low field MRI food inspection system prototype

Energy Technology Data Exchange (ETDEWEB)

Kawagoe, Satoshi, E-mail: s133413@edu.tut.ac.jp; Toyota, Hirotomo; Hatta, Junichi; Ariyoshi, Seiichiro; Tanaka, Saburo, E-mail: tanakas@ens.tut.ac.jp

2016-11-15

Highlights: • We have developed a ULF-MRI system using HTS-SQUID for food inspection. • We developed a compact magnetically shielded box to attenuate environmental noise. • The 2D-MR image was reconstructed from the grid processing data using 2D-FFT method. • The 2D-MR images of a disk-shaped and a multiple cell water sample were obtained. • The results showed the possibility of applying the ULF-MRI system to food inspection. - Abstract: We develop an ultra-low field (ULF) magnetic resonance imaging (MRI) system using a high-temperature superconducting quantum interference device (HTS-SQUID) for food inspection. A two-dimensional (2D)-MR image is reconstructed from the grid processing raw data using the 2D fast Fourier transform method. In a previous study, we combined an LC resonator with the ULF-MRI system to improve the detection area of the HTS-SQUID. The sensitivity was improved, but since the experiments were performed in a semi-open magnetically shielded room (MSR), external noise was a problem. In this study, we develop a compact magnetically shielded box (CMSB), which has a small open window for transfer of a pre-polarized sample. Experiments were performed in the CMSB and 2D-MR images were compared with images taken in the semi-open MSR. A clear image of a disk-shaped water sample is obtained, with an outer dimension closer to that of the real sample than in the image taken in the semi-open MSR. Furthermore, the 2D-MR image of a multiple cell water sample is clearly reconstructed. These results show the applicability of the ULF-MRI system in food inspection.

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.

A high pulsed power supply system designed for pulsed high magnetic field

International Nuclear Information System (INIS)

Liu Kefu; Wang Shaorong; Zhong Heqing; Xu Yan; Pan Yuan

2008-01-01

This paper introduces the design of high pulsed power supply system for producing pulsed high magnetic field up to 70 T. This system consists of 58 sets of 55 μF of capacitor bank which provides 1.0 MJ energy storage. A set of vacuum closing switch is chosen as main switch for energy discharge into magnetic coil. A crowbar circuit with high power diodes in series with resistor is used to absorb the redundant energy and adjust pulse width. The resistance of magnetic coil changing with current is deduced by energy balance equations. A capacitor-charging power supply using a series-resonant, constant on-time variable frequency control, and zero-current switching charges the capacitor bank in one minute time with high efficiency. The pulsed power supply provides adjustable current and pulse width with 30 kA peak and 30 ms maximum. The primary experiments demonstrate the system reliability. This work provides an engineering guidance for future development of pulsed high magnetic field. (authors)

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.

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

Wellbore Completion Systems Containment Breach Solution Experiments at a Large Scale Underground Research Laboratory : Sealant placement & scale-up from Lab to Field

Science.gov (United States)

Goodman, H.

2017-12-01

This investigation seeks to develop sealant technology that can restore containment to completed wells that suffer CO2 gas leakages currently untreatable using conventional technologies. Experimentation is performed at the Mont Terri Underground Research Laboratory (MT-URL) located in NW Switzerland. The laboratory affords investigators an intermediate-scale test site that bridges the gap between the laboratory bench and full field-scale conditions. Project focus is the development of CO2 leakage remediation capability using sealant technology. The experimental concept includes design and installation of a field scale completion package designed to mimic well systems heating-cooling conditions that may result in the development of micro-annuli detachments between the casing-cement-formation boundaries (Figure 1). Of particular interest is to test novel sealants that can be injected in to relatively narrow micro-annuli flow-paths of less than 120 microns aperture. Per a special report on CO2 storage submitted to the IPCC[1], active injection wells, along with inactive wells that have been abandoned, are identified as one of the most probable sources of leakage pathways for CO2 escape to the surface. Origins of pressure leakage common to injection well and completions architecture often occur due to tensile cracking from temperature cycles, micro-annulus by casing contraction (differential casing to cement sheath movement) and cement sheath channel development. This discussion summarizes the experiment capability and sealant testing results. The experiment concludes with overcoring of the entire mock-completion test site to assess sealant performance in 2018. [1] IPCC Special Report on Carbon Dioxide Capture and Storage (September 2005), section 5.7.2 Processes and pathways for release of CO2 from geological storage sites, page 244

A modified Stern-Gerlach experiment using a quantum two-state magnetic field

Science.gov (United States)

Daghigh, Ramin G.; Green, Michael D.; West, Christopher J.

2018-06-01

The Stern-Gerlach experiment has played an important role in our understanding of quantum behavior. We propose and analyze a modified version of this experiment where the magnetic field of the detector is in a quantum superposition, which may be experimentally realized using a superconducting flux qubit. We show that if incident spin-1/2 particles couple with the two-state magnetic field, a discrete target distribution results that resembles the distribution in the classical Stern-Gerlach experiment. As an application of the general result, we compute the distribution for a Gaussian waveform of the incident fermion. This analysis allows us to demonstrate theoretically: (1) the quantization of the intrinsic angular momentum of a spin-1/2 particle, and (2) a correlation between EPR pairs leading to nonlocality, without necessarily collapsing the particle's spin wavefunction.

Electromagnetic Emissions During Rock-fracturing Experiments Inside Magnetic Field Free Space

Science.gov (United States)

Wang, H.; Zhou, J.; Zhu, T.; Jin, H.

2012-12-01

Abnormal electromagnetic emission (EME) signal is one type of the most important precursors before earthquake, which has been widely observed and recorded before large earthquake, but the physical mechanism underlying the phenomenon is unclear and under controversy. Monitoring the EME signals during rock-fracturing experiments in laboratory is an effective way to study the phenomena and their underlying mechanism. Electromagnetic noise is everywhere because industrial and civilian electrical equipments have been widely used, which make difficulties to the in-lab experiments and field monitoring. To avoid the interference from electromagnetic noise, electromagnetic experiments must be carried out inside shielded space. Magnetic Field Free Space (MFFS) was constructed by Institute of Geophysics, China Earthquake Administration in 1980s. MFFS is a near-spherical polyhedron 'space' with 26 faces and inside diameter about 2.3 m. It is enclosed by 8-layer permalloy 1J85 for shielding magnetic field and 2-layer purified aluminium for shielding electric field. MFFS mainly shields static magnetic field by a factor of 160-4000 for the magnetic signals with the frequencies ranging from 0.01 Hz to 10 Hz. The intensity of magnetic field inside the space is less than 20 nT and its fluctuation is less than 0.3 nT in 90 hours. MFFS can dramatically shield EME signals in the frequency range of EME antennas utilized in our experiments, (several to ~320) kHz, by at least 90%, based on observation. Rock specimens (granite, marble) were fractured by two ways inside MFFS. 1) Cuboid bulk specimens were drilled, filled with static cracking agent, and then dilated from inside until fracture. 2) Cylindrical rock specimens were stressed until fracture by using a non-magnetic rock testing machine with the maximum testing force 300kN. EME, acoustic emission (AE) and strain signals were collected synchronously by the same data acquisitor, Acoustic Emission Workstation made by Physical Acoustics

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

A mobile field-work data collection system for the wireless era of health surveillance.

Science.gov (United States)

Forsell, Marianne; Sjögren, Petteri; Renard, Matthew; Johansson, Olle

2011-03-01

In many countries or regions the capacity of health care resources is below the needs of the population and new approaches for health surveillance are needed. Innovative projects, utilizing wireless communication technology, contribute to reliable methods for field-work data collection and reporting to databases. The objective was to describe a new version of a wireless IT-support system for field-work data collection and administration. The system requirements were drawn from the design objective and translated to system functions. The system architecture was based on fieldwork experiences and administrative requirements. The Smartphone devices were HTC Touch Diamond2s, while the system was based on a platform with Microsoft .NET components, and a SQL Server 2005 with Microsoft Windows Server 2003 operating system. The user interfaces were based on .NET programming, and Microsoft Windows Mobile operating system. A synchronization module enabled download of field data to the database, via a General Packet Radio Services (GPRS) to a Local Area Network (LAN) interface. The field-workers considered the here-described applications user-friendly and almost self-instructing. The office administrators considered that the back-office interface facilitated retrieval of health reports and invoice distribution. The current IT-support system facilitates short lead times from fieldwork data registration to analysis, and is suitable for various applications. The advantages of wireless technology, and paper-free data administration need to be increasingly emphasized in development programs, in order to facilitate reliable and transparent use of limited resources.

A computerised recording and monitoring system for extensive air shower experiments

International Nuclear Information System (INIS)

Naranan, S.; Rao, M.V.S.; Sivaprasad, K.; Subramaniam, P.B.

1975-01-01

A digital computer, TDC-12, with a memory capacity of 8 K 12-bit words and memory cycle time of 2 μs has been installed at the Cosmic Ray Laboratory at Kolar Gold Fields, India for real time operation with the KGF Air Shower Experiment. The computer system records the selected events and monitors and calibrates all the 90 detectors of various types in real time. (orig./WL) [de

The radiation monitoring system for the LHC experiments and experimental areas

CERN Document Server

Ilgner, C

2004-01-01

With the high energies stored in the beams of the LHC, special attention needs to be paid to accident scenarios involving beam losses which may have an impact on the installed experiments. Among others, an unsynchronized beam abort and a D1 magnet failure are considered serious cases. According to simulations, the CMS inner tracker in such accident scenarios can be damaged by instantaneous rates which are many orders of magnitude above normal conditions. Investigations of synthetic diamond as a beam condition monitor sensor, capable of generating a fast beam dump signal, will be presented. Furthermore, a system to monitor the radiation fields in the experimental areas is being developed. It must function in the radiation fields inside and around the experiments, over a large dynamic range. Several new active and passive sensors, such as RadFET, OSL (Optically Stimulated Luminescence) sensors, p-i-n diodes, Polymer-Alanine Dosimeters and TLDs (Thermoluminescent Dosimeters) are under investigation. Recent resul...

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.

Theory of field-reversed mirrors and field-reversed plasma-gun experiments. Paper IAEA-CN-38/R-2

International Nuclear Information System (INIS)

Anderson, D.V.; Auerbach, S.P.; Berk, H.L.

1980-01-01

Experimental and theoretical studies of field reversal in a mirror machine are reported. Plasma-gun experiments demonstrate that reversed-field plasma layers are formed. Low energy plasma flowing behind the initially produced plasma front prevents tearing of the layer from the gun muzzle. MHD simulation shows that tearing can be obtained by impeding the slow plasma flow with a plasma divider. It is demonstrated theoretically that a field-reversed mirror imbedded in a multipole field can be sustained in steady state with neutral-beam injection even in the absence of impurities. MHD stability analysis shows that growth rates of elongated reversed-field theta-pinch configurations decrease with axial extension, which indicates the importance of including finite Larmor radius in the analysis. Tilting-mode criteria are improved by proper shaping, and a problimak shape is proposed. Tearing mode stability of reversed-field theta-pinches is greatly enhanced by flux exclusion. Self-consistent, 1-1/2-dimensional transport codes have been developed, and initial results are presented

Theory of field-reversed mirrors and field-reversed plasma-gun experiments. Paper IAEA-CN-38/R-2

International Nuclear Information System (INIS)

Anderson, D.V.; Auerbach, S.P.; Berk, H.L.

1980-01-01

Experimental and theoretical studies of field reversal in a mirror machine are reported. Plasma-gun experiments demonstrate that reversed-field plasma layers are formed. Low energy plasma flowing behind the initially produced plasma front prevents tearing of the layer from the gun muzzle. MHD simulation shows that tearing can be obtained by impeding the slow plasma flow with a plasma divider. It is demonstrated theoretically that a field-reversed mirror imbedded in a multipole field can be sustained in steady state with neutral-beam injection even in the absence of impurities. MHD stability analysis shows that growth rates of elongated reversed-field theta-pinch configurations decrease with axial extension, which indicates the importance of including finite Larmor radius in the analysis. Tilting-mode criteria are dramatically improved by proper shaping, and a problimak shape is proposed. Tearing mode stability of reversed-field theta-pinches is greatly enhanced by flux exclusion. Self-consistent, 1-1/2-dimensional transport codes have been developed, and initial results are presented

The magnet power control system for the tandem mirror experiment-upgrade

International Nuclear Information System (INIS)

Bell, H.H.

1983-01-01

This paper describes the desktop computer/CAMAC based system that controls the power source for the Tandem Mirror Experiment-Upgrade (TMX-U) magnet power system. Presently it contains 42 dc rectifier power supplies connected to 24 magnet coils arranged in 17 circuits. During each shot, the system delivers 22.6 MW dc to the magnets for about 3 s. The system is presently being changed to add six power supplies, two solenoidal throttle coils, and two reverse C-coils. When complete, the delivered power will increase to 36.9 MW. The closed-loop control system usually provides current (and thus, magnetic field) that is within 1% of the requested current. Achieving this accuracy required using grounding, shielding, and isolation methods to reduce noise and related problems

The Calibration System of the E989 Experiment at Fermilab

Energy Technology Data Exchange (ETDEWEB)

Anastasi, Antonio [Univ. of Messina (Italy)

2017-01-01

The muon anomaly aµ is one of the most precise quantity known in physics experimentally and theoretically. The high level of accuracy permits to use the measurement of aµ as a test of the Standard Model comparing with the theoretical calculation. After the impressive result obtained at Brookhaven National Laboratory in 2001 with a total accuracy of 0.54 ppm, a new experiment E989 is under construction at Fermilab, motivated by the diff of aexp SM µ ^- aµ ~ 3σ. The purpose of the E989 experiment is a fourfold reduction of the error, with a goal of 0.14 ppm, improving both the systematic and statistical uncertainty. With the use of the Fermilab beam complex a statistic of × 21 with respect to BNL will be reached in almost 2 years of data taking improving the statistical uncertainty to 0.1 ppm. Improvement on the systematic error involves the measurement technique of ωa and ωp, the anomalous precession frequency of the muon and the Larmor precession frequency of the proton respectively. The measurement of ωp involves the magnetic field measurement and improvements on this sector related to the uniformity of the field should reduce the systematic uncertainty with respect to BNL from 170 ppb to 70 ppb. A reduction from 180 ppb to 70 ppb is also required for the measurement of ωa; new DAQ, a faster electronics and new detectors and calibration system will be implemented with respect to E821 to reach this goal. In particular the laser calibration system will reduce the systematic error due to gain fl of the photodetectors from 0.12 to 0.02 ppm. The 0.02 ppm limit on systematic requires a system with a stability of 10^-4 on short time scale (700 µs) while on longer time scale the stability is at the percent level. The 10^-4 stability level required is almost an order of magnitude better than the existing laser calibration system in particle physics, making the calibration system a very challenging item. In addition to the high level

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.

Evaluation of Fast-Time Wake Models Using Denver 2006 Field Experiment Data

Science.gov (United States)

Ahmad, Nash’at N.; Pruis, Matthew J.

2015-01-01

The National Aeronautics and Space Administration conducted a series of wake vortex field experiments at Denver in 2003, 2005, and 2006. This paper describes the lidar wake vortex measurements and associated meteorological data collected during the 2006 deployment, and includes results of recent reprocessing of the lidar data using a new wake vortex algorithm and estimates of the atmospheric turbulence using a new algorithm to estimate eddy dissipation rate from the lidar data. The configuration and set-up of the 2006 field experiment allowed out-of-ground effect vortices to be tracked in lateral transport further than any previous campaign and thereby provides an opportunity to study long-lived wake vortices in moderate to low crosswinds. An evaluation of NASA's fast-time wake vortex transport and decay models using the dataset shows similar performance as previous studies using other field data.

Design and development of the helicity injection system in Versatile Experiment Spherical Torus

International Nuclear Information System (INIS)

Park, JongYoon; An, Younghwa; Jung, Bongki; Lee, Jeongwon; Lee, HyunYoung; Chung, Kyoung-Jae; Na, Yong-Su; Hwang, Y.S.

2015-01-01

Graphical abstract: - Highlights: • A high current electron gun with single pulse power for both arc and extraction is developed. • The optimal gun operation is confirmed by impedance matching between the PFN and plasma. • The gun injected currents of 0.95 kA with the voltage of ∼410 V for 5 ms with a 1.2 kV PFN. • The helicity injection system using the gun has been developed and tested successfully in VEST. • Toroidal currents of up to 3.8 kA confirm possible relaxation into tokamak-like plasma. - Abstract: A helicity injection system for the Versatile Experiment Spherical Torus (VEST) has been successfully developed and commissioned. A high current electron gun utilizing hollow cathode and washer stacks has been designed and constructed with a single pulse power system that can provide voltages for both arc discharge and extraction sequentially. Tests for electron gun operation with the single pulse power system have been conducted under various toroidal and poloidal field strengths. The estimated plasma impedance, depending on the injection magnetic field structure, can be utilized for the optimal gun operation by impedance matching between the pulse power system and plasma. With the charging voltage of 1.2 kV, injection current of 0.95 kA has been obtained with the injection voltage of 410 V for about 5 ms. Initial helicity injection experiments have been conducted under various toroidal and poloidal field strengths and a toroidal plasma current of up to 3.8 kA is observed with the current multiplication larger than the geometric stacking ratio, confirming the possibility of relaxation into tokamak-like plasma with closed flux formation.

Design and development of the helicity injection system in Versatile Experiment Spherical Torus

Energy Technology Data Exchange (ETDEWEB)

Park, JongYoon; An, Younghwa; Jung, Bongki; Lee, Jeongwon; Lee, HyunYoung; Chung, Kyoung-Jae; Na, Yong-Su; Hwang, Y.S., E-mail: yhwang@snu.ac.kr

2015-10-15

Graphical abstract: - Highlights: • A high current electron gun with single pulse power for both arc and extraction is developed. • The optimal gun operation is confirmed by impedance matching between the PFN and plasma. • The gun injected currents of 0.95 kA with the voltage of ∼410 V for 5 ms with a 1.2 kV PFN. • The helicity injection system using the gun has been developed and tested successfully in VEST. • Toroidal currents of up to 3.8 kA confirm possible relaxation into tokamak-like plasma. - Abstract: A helicity injection system for the Versatile Experiment Spherical Torus (VEST) has been successfully developed and commissioned. A high current electron gun utilizing hollow cathode and washer stacks has been designed and constructed with a single pulse power system that can provide voltages for both arc discharge and extraction sequentially. Tests for electron gun operation with the single pulse power system have been conducted under various toroidal and poloidal field strengths. The estimated plasma impedance, depending on the injection magnetic field structure, can be utilized for the optimal gun operation by impedance matching between the pulse power system and plasma. With the charging voltage of 1.2 kV, injection current of 0.95 kA has been obtained with the injection voltage of 410 V for about 5 ms. Initial helicity injection experiments have been conducted under various toroidal and poloidal field strengths and a toroidal plasma current of up to 3.8 kA is observed with the current multiplication larger than the geometric stacking ratio, confirming the possibility of relaxation into tokamak-like plasma with closed flux formation.

Enabling Field Experiences in Introductory Geoscience Classes through the Use of Immersive Virtual Reality

Science.gov (United States)

Moysey, S. M.; Smith, E.; Sellers, V.; Wyant, P.; Boyer, D. M.; Mobley, C.; Brame, S.

2015-12-01

Although field experiences are an important aspect of geoscience education, the opportunity to provide physical world experiences to large groups of introductory students is often limited by access, logistical, and financial constraints. Our project (NSF IUSE 1504619) is investigating the use of immersive virtual reality (VR) technologies as a surrogate for real field experiences in introductory geosciences classes. We are developing a toolbox that leverages innovations in the field of VR, including the Oculus Rift and Google Cardboard, to enable every student in an introductory geology classroom the opportunity to have a first-person virtual field experience in the Grand Canyon. We have opted to structure our VR experience as an interactive game where students must explore the Canyon to accomplish a series of tasks designed to emphasize key aspects of geoscience learning. So far we have produced two demo products for the virtual field trip. The first is a standalone "Rock Box" app developed for the iPhone, which allows students to select different rock samples, examine them in 3D, and obtain basic information about the properties of each sample. The app can act as a supplement to the traditional rock box used in physical geology labs. The second product is a fully functioning VR environment for the Grand Canyon developed using satellite-based topographic and imagery data to retain real geologic features within the experience. Players can freely navigate to explore anywhere they desire within the Canyon, but are guided to points of interest where they are able to complete exercises that will be aligned with specific learning goals. To this point we have integrated elements of the "Rock Box" app within the VR environment, allowing players to examine 3D details of rock samples they encounter within the Grand Canyon. We plan to provide demos of both products and obtain user feedback during our presentation.

Field experiments with subsurface releases of oil and and dyed water

International Nuclear Information System (INIS)

Rye, H.; Brandvik, P.J.; Strom, T.

1998-01-01

A field experiment with a subsurface release of oil and air was carried out in June 1996 close to the Frigg Field in the North Sea area. One of the purposes of this sea trial was to increase the knowledge concerning the behaviour of the oil and gas during a subsurface blowout. This was done by releasing oil and air at 106 meters depth with a realistic gas oil ratio (GOR=67) and release velocity of the oil. In addition to the oil release, several releases with dyed water and gas (GOR=7 - 65) were performed. Important and unique data were collected during these subsurface releases. In particular, the experiments with the dyed water releases combined with air turned out to be an efficient way of obtaining field data for the behaviour of subsurface plumes. The main conclusions from analysis for the data collected are: the field methodology used to study blowout releases in the field appears to be appropriate. The use of dyed water to determine the performance of the subsurface plume proved out to be an efficient way to obtain reliable and useful data. The behaviour of the subsurface plume is very sensitive to gas flow rates. For low gas flow rates, the plume did not reach the sea surface at all due to the presence of stratification in the ambient water. Some discrepancies were found between a numerical model for subsurface releases and field results. These discrepancies are pointed out, and recommendations for possible model improvements are given. (author)

Evaluating the soil physical quality under long-term field experiments in Southern Italy

Science.gov (United States)

Castellini, Mirko; Stellacci, Anna Maria; Iovino, Massimo; Rinaldi, Michele; Ventrella, Domenico

2017-04-01

Long-term field experiments performed in experimental farms are important research tools to assess the soil physical quality (SPQ) given that relatively stable conditions can be expected in these soils. However, different SPQ indicators may sometimes provide redundant or conflicting results, making difficult an SPQ evaluation (Castellini et al., 2014). As a consequence, it is necessary to apply appropriate statistical procedures to obtain a minimum set of key indicators. The study was carried out at the Experimental Farm of CREA-SCA (Foggia) in two long-term field experiments performed on durum wheat. The first long-term experiment is aiming at evaluating the effects of two residue management systems (burning, B or soil incorporation of crop residues, I) while the second at comparing the effect of tillage (conventional tillage, CT) and sod-seeding (direct drilling, DD). In order to take into account both optimal and non-optimal soil conditions, five SPQ indicators were monitored at 5-6 sampling dates during the crop season (i.e., between November and June): soil bulk density (BD), macroporosity (PMAC), air capacity (AC), plant available water capacity (PAWC) and relative field capacity (RFC). Two additional data sets, collected on DD plot in different cropping seasons and in Sicilian soils differing for texture, depth and land use (N=140), were also used with the aim to check the correlation among indicators. Impact of soil management was assessed by comparing SPQ evaluated under different management systems with optimal reference values reported in literature. Two techniques of multivariate analysis (principal component analysis, PCA and stepwise discriminant analysis, SDA) were applied to select the most suitable indicator to facilitate the judgment on SPQ. Regardless of the considered management system, sampling date or auxiliary data set, correlation matrices always showed significant negative relationships between RFC and AC. Decreasing RFC at increasing AC is

Development of Work Verification System for Cooperation between MCR Operators and Field Workers in Nuclear Power Plants

International Nuclear Information System (INIS)

Lee, Seung Min; Seong, Poong Hyun; Lee, Hyun Chul

2014-01-01

In this work, as an application of digital devices to NPPs, a cooperation support system to aid communication between MCR operators and field workers in Nuclear Power Plants (NPPs), NUclear COoperation Support and MObile document System (Nu-COSMOS), is suggested. It is not easy for MCR operators to estimate whether field workers conduct their work correctly because MCR operators cannot monitor field workers at a real time, and records on paper procedure written by field workers do not contain the detailed information about work process and results. Thus, for safety operation without any events induced by misunderstand and miscommunication between MCR operators and field workers, the Nu-COSMOS is developed and it will be useful from the supporting cooperation point of view. To support the cooperation between MCR operators and field workers in NPPs, the cooperation support and mobile documentation system Nu-COSMOS is suggested in this work. To improve usability and applicability of the suggested system, the results of using existed digital device based support systems were analyzed. Through the analysis, the disincentive elements of using digital device-based developments and the recommendations for developing new mobile based system were derived. Based on derived recommendations, two sub systems, the mobile device based in-formation storing system and the large screen based information sharing system were suggested. The usability of the suggested system will be conducted by a survey with questionnaires. Field workers and operators, and nuclear-related person who had experiences as an operator, graduate students affiliated in nuclear engineering department will use and test the functions of the suggested system. It is expected that the mobile based information storing system can reduce the field workers' work load and enhance the understanding of MCR operators about field operators work process by monitoring all work results and work processes stored in devices

Development of Work Verification System for Cooperation between MCR Operators and Field Workers in Nuclear Power Plants

Energy Technology Data Exchange (ETDEWEB)

Lee, Seung Min; Seong, Poong Hyun [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Lee, Hyun Chul [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2014-05-15

In this work, as an application of digital devices to NPPs, a cooperation support system to aid communication between MCR operators and field workers in Nuclear Power Plants (NPPs), NUclear COoperation Support and MObile document System (Nu-COSMOS), is suggested. It is not easy for MCR operators to estimate whether field workers conduct their work correctly because MCR operators cannot monitor field workers at a real time, and records on paper procedure written by field workers do not contain the detailed information about work process and results. Thus, for safety operation without any events induced by misunderstand and miscommunication between MCR operators and field workers, the Nu-COSMOS is developed and it will be useful from the supporting cooperation point of view. To support the cooperation between MCR operators and field workers in NPPs, the cooperation support and mobile documentation system Nu-COSMOS is suggested in this work. To improve usability and applicability of the suggested system, the results of using existed digital device based support systems were analyzed. Through the analysis, the disincentive elements of using digital device-based developments and the recommendations for developing new mobile based system were derived. Based on derived recommendations, two sub systems, the mobile device based in-formation storing system and the large screen based information sharing system were suggested. The usability of the suggested system will be conducted by a survey with questionnaires. Field workers and operators, and nuclear-related person who had experiences as an operator, graduate students affiliated in nuclear engineering department will use and test the functions of the suggested system. It is expected that the mobile based information storing system can reduce the field workers' work load and enhance the understanding of MCR operators about field operators work process by monitoring all work results and work processes stored in devices.

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.

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

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)

Designing and Using Virtual Field Environments to Enhance and Extend Field Experience in Professional Development Programs in Geology for K-12 Teachers

Science.gov (United States)

Granshaw, Frank Douglas

2011-12-01

Virtual reality (VR) is increasingly used to acquaint geoscience novices with some of the observation, data gathering, and problem solving done in actual field situations by geoscientists. VR environments in a variety of forms are used to prepare students for doing geologic fieldwork, as well as to provide proxies for such experience when venturing into the field is not possible. However, despite increased use of VR for these purposes, there is little research on how students learn using these environments, how using them impacts student field experience, or what constitutes effective design in light of emerging theories of geocognition. To address these questions, I investigated the design and use of a virtual reality environment in a professional development program for middle school Earth science teachers called Teachers on the Leading Edge (TOTLE). This environment, called a virtual field environment, or VFE, was based largely on the field sites visited by the participants during summer workshops. It was designed as a tool to prepare the participants for workshop field activities and as a vehicle for taking elements of that experience back to their students. I assessed how effectively the VFE accomplished these goals using a quasi-experimental, mixed method study that involved a series of teaching experiments, interviews, participant surveys, and focus groups. The principle conclusions reached in this study are as follows: 1. In a field trip orientation experiment involving 35 middle school teachers, 90.6% of the participants stated a preference for VFE enhanced orientation over an alternative orientation that used photographs and static maps to complete a practice field activity. When asked about how the VFE prepared them for their field experience, the participants ranked it as most helpful for visualize the location and geography of the field sites. They ranked it lower for helping them visualize structural and geomorphic patterns, and ranked it as least

Field-Testing a PC Electronic Documentation System using the Clinical Care Classification© System with Nursing Students

Directory of Open Access Journals (Sweden)

Jennifer E. Mannino

2011-01-01

Full Text Available Schools of nursing are slow in training their students to keep up with the fast approaching era of electronic healthcare documentation. This paper discusses the importance of nursing documentation, and describes the field-testing of an electronic health record, the Sabacare Clinical Care Classification (CCC© system. The PC-CCC©, designed as a Microsoft Access® application, is an evidence-based electronic documentation system available via free download from the internet. A sample of baccalaureate nursing students from a mid-Atlantic private college used this program to document the nursing care they provided to patients during their sophomore level clinical experience. This paper summarizes the design, training, and evaluation of using the system in practice.

Phased-array antenna system for electron Bernstein wave heating and current drive experiments in QUEST

International Nuclear Information System (INIS)

Idei, H.; Sakaguchi, M.; Kalinnikova, E.I.

2010-11-01

The phased-array antenna system for Electron Bernstein Wave Heating and Current Drive (EBWH/CD) experiments has been developed in the QUEST. The antenna was designed to excite a pure O-mode wave in the oblique injection for the EBWH/CD experiments, and was tested at a low power level. The measured two orthogonal fields were in excellent agreements with the fields evaluated by a developed Kirchhoff code. The heat load and thermal stress in CW 200 kW operation were analyzed with finite element codes. The phased array has been fast scanned [∼10 4 degree/s] to control the incident polarization and angle to follow time evolutions of the plasma current and density. The RF startup and sustainment experiments were conducted using the developed antenna system. The plasma current (< ∼15 kA) with an aspect ratio of 1.5 was started up and sustained by only RF injection. The long pulse discharge of 10 kA was attained for 40 s with the 30 kW injection. (author)

Plot-scale field experiment of surface hydrologic processes with EOS implications

Science.gov (United States)

Laymon, Charles A.; Macari, Emir J.; Costes, Nicholas C.

1992-01-01

Plot-scale hydrologic field studies were initiated at NASA Marshall Space Flight Center to a) investigate the spatial and temporal variability of surface and subsurface hydrologic processes, particularly as affected by vegetation, and b) develop experimental techniques and associated instrumentation methodology to study hydrologic processes at increasingly large spatial scales. About 150 instruments, most of which are remotely operated, have been installed at the field site to monitor ground atmospheric conditions, precipitation, interception, soil-water status, and energy flux. This paper describes the nature of the field experiment, instrumentation and sampling rationale, and presents preliminary findings.

Validation of dispersion model of RTARC-DSS based on ''KIT'' field experiments

International Nuclear Information System (INIS)

Duran, J.

2000-01-01

The aim of this study is to present the performance of the Gaussian dispersion model RTARC-DSS (Real Time Accident Release Consequences - Decision Support System) at the 'Kit' field experiments. The Model Validation Kit is a collection of three experimental data sets from Kincaid, Copenhagen, Lillestrom and supplementary Indianopolis experimental campaigns accompanied by software for model evaluation. The validation of the model has been performed on the basis of the maximum arc-wise concentrations using the Bootstrap resampling procedure the variation of the model residuals. Validation was performed for the short-range distances (about 1 - 10 km, maximum for Kincaid data set - 50 km from source). Model evaluation procedure and amount of relative over- or under-prediction are discussed and compared with the model. (author)

The GeoFlow experiment-spherical Rayleigh-Benard convection under the influence of an artificial central force field

International Nuclear Information System (INIS)

Gellert, M; Beltrame, P; Egbers, C

2005-01-01

Spherical Rayleigh-Benard convection under the influence of an artificial central force field produced by the so-called dielectrophoretic effect is studied as a simplified model of the flow in the outer earth core. The fluid motion there is most probably driving the earth's dynamo and the energy source for the earth's magnetic field. Studying convective flows in earth-like geometry could lead to a deeper understanding of the basics of these processes. This research is a preparatory study for the experiments on the International Space Station (ISS). A bifurcation-theoretical approach shows the existence of heteroclinic cycles between spherical modes (l, l + 1) for the non-rotating system. This behavior depends strong on the radius ratio of the spheres and will be hard to detect in the experiment. For slow rotations interactions of the azimuthal modes (m, m + 1) found in numerical simulations for supercritical states are supposed to be experimentally observable

Measuring the vertical electrical field above an oceanic convection system using a meteorological sounding balloon

Science.gov (United States)

Chen, A. B.; Chiu, C.; Lai, S.; Chen, C.; Kuo, C.; Su, H.; Hsu, R.

2012-12-01

The vertical electric field above thundercloud plays an important role in the generation and modeling of transient luminous events. For example, Pasko [1995] proposed that the high quasi-static E-field following the positive cloud-to-ground lightning could accelerate and input energy to ambient electrons; as they collide and excite nitrogen and oxygen molecules in upper atmosphere, sprites may be induced. A series of balloon experiments led by Holzworth have investigated the temporal and spatial fluctuations of the electric field and conductivity in the upper atmosphere at different sites [Holzworth 2005, and references in]. But the strength and variation of the vertical electric field above thundercloud, especially oceanic ones, are not well documented so far. A lightweight, low-cost measurement system including an electric field meter and the associated aviation electronics are developed to carry out the in-situ measurement of the vertical electric field and the inter-cloud charge distribution. Our measuring system was first deployed using a meteorological sounding balloon from Taitung, Taiwan in May 2012. The measured electric field below 3km height shows an exponential decay and it is consistent with the expected potential gradient variation between ionosphere and the Earth surface. But the background strength of the measured E-field grows up exponentially and a violent fluctuations is also observed when the balloon flew over a developing oceanic convection cell. The preliminary results from this flight will be reported and discussed. This low-cost electric field meter is developed within one year. In the coming months, more flights will be performed with the aim to measure the rapid variation of the electric field above thundercloud as well as the E-field that may induce transient luminous events. Our ground campaigns show that the occurrence rates of blue and gigantic jet are relatively high in the vicinity of Taiwan. Our experiment can be used to diagnose

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

Magnetic Field Response Measurement Acquisition System

Science.gov (United States)

Woodard, Stanley E.; Taylor,Bryant D.; Shams, Qamar A.; Fox, Robert L.

2007-01-01

This paper presents a measurement acquisition method that alleviates many shortcomings of traditional measurement systems. The shortcomings are a finite number of measurement channels, weight penalty associated with measurements, electrical arcing, wire degradations due to wear or chemical decay and the logistics needed to add new sensors. Wire degradation has resulted in aircraft fatalities and critical space launches being delayed. The key to this method is the use of sensors designed as passive inductor-capacitor circuits that produce magnetic field responses. The response attributes correspond to states of physical properties for which the sensors measure. Power is wirelessly provided to the sensing element by using Faraday induction. A radio frequency antenna produces a time-varying magnetic field used to power the sensor and receive the magnetic field response of the sensor. An interrogation system for discerning changes in the sensor response frequency, resistance and amplitude has been developed and is presented herein. Multiple sensors can be interrogated using this method. The method eliminates the need for a data acquisition channel dedicated to each sensor. The method does not require the sensors to be near the acquisition hardware. Methods of developing magnetic field response sensors and the influence of key parameters on measurement acquisition are discussed. Examples of magnetic field response sensors and the respective measurement characterizations are presented. Implementation of this method on an aerospace system is discussed.

Equilibrium system analysis in a tokamak ignition experiment. Final report

Energy Technology Data Exchange (ETDEWEB)

Carrera, R.; Weldon, W.F.; Woodson, H.H.

1989-10-01

The objective of the IGNITEX Project is to produce and control ignited plasmas for scientific study in the simplest and least expensive way possible. The original concept was proposed by both physics and engineering researchers along the following line of thought. Question: Is there any theoretically simple, compact and reliable way of achieving fusion ignition according to the results of the fusion research program for the last decades? Answer: Yes. An experiment to be carried out in an ohmically heated compact tokamak device with 20 T field on plasma axis. Question: Is there any practical way to carry out that experiment at low cost in the near term? Answer: Yes. Using a single-turn coil magnet system with homopolar power supplies.

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…

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.

Design of the data acquisition system for the nuclear physics experiments at VECC

International Nuclear Information System (INIS)

Dhara, P.; Roy, A.; Maity, P.; Singhai, P.; Roy, P.S.

2012-01-01

The beam from K130 room temperature cyclotron is being extensively used for nuclear physics experiments for last three decades. The typical beam energy for the experiments is approximately 7-10 MeV/nucleon for heavy ions and 8-20 MeV/nucleon for light ions. The number of detectors used, may vary from one channel to few hundreds of detector channels. The proposed detector system for experiments with the superconducting cyclotron may have more than 1200 detector channels, and may be generating more than one million parameters per second. The VME (Versa Module Europa) and CAMAC (Computer Automated Measurement and Control) based data acquisition system (DAQ) is being used to cater the experimental needs. The current system has been designed based on various commercially available modules in NIM (Nuclear Instrumentation Module), CAMAC and VME form factor. This type of setup becomes very complicated to maintain for large number of detectors. Alternatively, the distributed DAQ system based on embedded technology is proposed. The traditional analog processing may be replaced by digital filters based FPGA (Field Programmable Gate Array) boards. This paper describes the design of current DAQ system and the status of the proposed scheme for distributed DAQ system with capability of handling heterogeneous detector systems. (author)

Propositional systems in local field theories

International Nuclear Information System (INIS)

Banai, M.

1980-07-01

The authors investigate propositional systems for local field theories, which reflect intrinsically the uncertainties of measurements made on the physical system, and satisfy the isotony and local commutativity postulates of Haag and Kastler. The spacetime covariance can be implemented in natural way in these propositional systems. New techniques are introduced to obtain these propositional systems: the lattice-valued logics. The decomposition of the complete orthomodular lattice-valued logics shows that these logics are more general than the usual two-valued ones and that in these logics there is enough structure to characterize the classical and quantum, non relativistic and relativistic local field theories in a natural way. The Hilbert modules give the natural inner product ''spaces'' (modules) for the realization of the lattice-valued logics. (author)

Interference experiment with asymmetric double slit by using 1.2-MV field emission transmission electron microscope.

Science.gov (United States)

Harada, Ken; Akashi, Tetsuya; Niitsu, Kodai; Shimada, Keiko; Ono, Yoshimasa A; Shindo, Daisuke; Shinada, Hiroyuki; Mori, Shigeo

2018-01-17

Advanced electron microscopy technologies have made it possible to perform precise double-slit interference experiments. We used a 1.2-MV field emission electron microscope providing coherent electron waves and a direct detection camera system enabling single-electron detections at a sub-second exposure time. We developed a method to perform the interference experiment by using an asymmetric double-slit fabricated by a focused ion beam instrument and by operating the microscope under a "pre-Fraunhofer" condition, different from the Fraunhofer condition of conventional double-slit experiments. Here, pre-Fraunhofer condition means that each single-slit observation was performed under the Fraunhofer condition, while the double-slit observations were performed under the Fresnel condition. The interference experiments with each single slit and with the asymmetric double slit were carried out under two different electron dose conditions: high-dose for calculation of electron probability distribution and low-dose for each single electron distribution. Finally, we exemplified the distribution of single electrons by color-coding according to the above three types of experiments as a composite image.

Cross polarization with phase and amplitude modulation of radio frequency fields in NMR-experiments with sample rotation at magic angle

International Nuclear Information System (INIS)

Dvinskij, S.V.; Chizhik, V.I.

2006-01-01

One analyzes cross polarization of nuclei within a rotating system of coordinates as applied to the NMR-experiments with a specimen rotation under the magic angle. One worded a concept of simultaneous phase and amplitude modulation according to which the Hamiltonian form of the restored dipole interaction persisted if inversion of difference of radiofrequency field amplitudes occurred simultaneously with phase inversion. One presents a theoretical substantiation in terms of the average Hamiltonian theory. The concept is demonstrated both experimentally and by means of numerical analysis for a number of special cases. Phase periodic inversion in cross polarized experiments is shown to result into practically important advantage of suppression of interactions of chemical shift and influence of effects of coarse adjustment of radiofrequency field parameters [ru

A fast and flexible panoramic virtual reality system for behavioural and electrophysiological experiments.

Science.gov (United States)

Takalo, Jouni; Piironen, Arto; Honkanen, Anna; Lempeä, Mikko; Aikio, Mika; Tuukkanen, Tuomas; Vähäsöyrinki, Mikko

2012-01-01

Ideally, neuronal functions would be studied by performing experiments with unconstrained animals whilst they behave in their natural environment. Although this is not feasible currently for most animal models, one can mimic the natural environment in the laboratory by using a virtual reality (VR) environment. Here we present a novel VR system based upon a spherical projection of computer generated images using a modified commercial data projector with an add-on fish-eye lens. This system provides equidistant visual stimulation with extensive coverage of the visual field, high spatio-temporal resolution and flexible stimulus generation using a standard computer. It also includes a track-ball system for closed-loop behavioural experiments with walking animals. We present a detailed description of the system and characterize it thoroughly. Finally, we demonstrate the VR system's performance whilst operating in closed-loop conditions by showing the movement trajectories of the cockroaches during exploratory behaviour in a VR forest.

Absorption of electromagnetic field energy by superfluid system of atoms with electric dipole moment

International Nuclear Information System (INIS)

Poluektov, Yu.M.

2014-01-01

The modified Gross-Pitaevskii equation which takes into account relaxation and interaction with alternating electromagnetic field is used to consider the absorption of electromagnetic field energy by a superfluid system on the assumption that the atoms has intrinsic dipole moment. It is shown that the absorption may be of a resonant behavior only if the dispersion curves of the electromagnetic wave and the excitations of the superfluid system intersect. It is remarkable that such a situation is possible if the superfluid system has a branch of excitations with the energy gap at low momenta. The experiments on absorption of microwaves in superfluid helium are interpreted as evidence of existence of such gap excitations. A possible modification of the excitation spectrum of superfluid helium in the presence of excitation branch with energy gap is dis-cussed qualitatively

Observed chlorine concentrations during Jack Rabbit I and Lyme Bay field experiments

Science.gov (United States)

Hanna, Steven; Chang, Joseph; Huq, Pablo

2016-01-01

As part of planning for a series of field experiments where large quantities (up to 20 tons) of pressurized liquefied chlorine will be released, observations from previous chlorine field experiments are analyzed to estimate the ranges of chlorine concentrations expected at various downwind distances. In five field experiment days during the summer 2010 Jack Rabbit I (JR I) field trials, up to two tons of chlorine were released and concentrations were observed at distances, x, from 25 to 500 m. In the 1927 Lyme Bay (LB) experiments, there were four days of trials, where 3-10 tons of chlorine were released in about 15 min from the back of a ship. Concentrations were sampled at LB from four ships sailing across the cloud path at downwind distances in the range from about 350 to 3000 m. Thus, the distances from which JR I concentrations were available slightly overlapped the LB distances. One-minute arc-maximum chlorine concentrations, C (g/m3), were analyzed from four JR I trials and two LB trials. Normalized concentrations (Cu/Q) were plotted versus x (m), where u (m/s) is measured wind speed at heights of 2-10 m and Q (g/s) is continuous mass release rate. It is found that the JR I and LB Cu/Q observations smoothly merge with each other and fall along a line with approximate slope of -2 at distances beyond about 200 m (i.e., Cu/Q is proportional to x-2). At x < 200 m, where dense gas effects are more important, the slope is less (about -1.5). Most of the data points are within a factor of two of the "best-fit" line.

Performance of a shallow-focus applied-magnetic-field diode for ion-beam-transport experiments

Energy Technology Data Exchange (ETDEWEB)

Young, F.C.; Neri, J.M.; Ottinger, P.F. [Naval Research Lab., Washington, DC (United States); Rose, D.V. [JAYCOR, Vienna (Vatican City State, Holy See); Jones, T.G.; Oliver, B.V.

1997-12-31

An applied-magnetic-field ion diode to study the transport of intense ion beams for light-ion inertial confinement fusion is being operated on the Gamble II generator at NRL. A Large-area (145-cm{sup 2}), shallow-focusing diode is used to provide the ion beam required for self-pinched transport (SPT) experiments. Experiments have demonstrated focusing at 70 cm for 1.2-MV, 40-kA protons. Beyond the focus, the beam hollows out consistent with 20--30 mrad microdivergence. The effect of the counter-pulse B-field on altering the ion-beam trajectories and improving the focus has been diagnosed with a multiple-pinhole-camera using radiachromic film. This diagnostic is also used to determine the radial and azimuthal uniformity of ion emission at the anode for different B-field conditions. Increasing the diode voltage to 1.5 MV and optimizing the ion current are planned before initiating SPT experiments. Experiments to measure the spatial beam profile at focus, i.e., the SPT channel entrance, are in progress. Results are presented.

Magnetic field-aligned plasma expansion in critical ionization velocity space experiments

International Nuclear Information System (INIS)

Singh, N.

1989-01-01

Motivated by the recent Critical Ionization Velocity (CIV) experiments in space, the temporal evolution of a plasma cloud released in an ambient plasma is studied. Time-dependent Vlasov equations for both electrons and ions, along with the Poisson equation for the self-consistent electric field parallel to the ambient magnetic field, are solved. The initial cloud is assumed to consist of cold, warm, and hot electrons with temperatures T/sub c/ ≅ 0.2 eV, T/sub w/ ≅ 2 eV, and T/sub h/ ≅ 10 eV, respectively. It is found that the minor hot electrons escape the cloud, and their velocity distribution function shows the typical time-of-flight dispersion feature - that is, the larger the distance from the cloud, the larger is the average drift velocity of the escaping electrons. The major warm electrons expand along the magnetic field line with the corresponding ion-acoustic speed. The combined effect of the escaping hot electrons and the expanding warm ones sets up an electric potential structure which accelerates the ambient electrons into the cloud. Thus, the energy loss due to the electron escape is partly replenished. The electric field distribution in the potential structure depends on the stage of the evolution; before the rarefaction waves propagating from the edges of the cloud reach its center, the electric fields point into the cloud. After this stage the cloud divides into two subclouds, with each having their own bipolar electric fields. Effects of collisions on the evolution of plasma clouds are also discussed. The relevance of the results seen from the calculations are discussed in the context of recent space experiments on CIV

Effects of high-intensity static magnetic fields on a root-based bioreactor system for space applications

Science.gov (United States)

Villani, Maria Elena; Massa, Silvia; Lopresto, Vanni; Pinto, Rosanna; Salzano, Anna Maria; Scaloni, Andrea; Benvenuto, Eugenio; Desiderio, Angiola

2017-11-01

Static magnetic fields created by superconducting magnets have been proposed as an effective solution to protect spacecrafts and planetary stations from cosmic radiations. This shield can deflect high-energy particles exerting injurious effects on living organisms, including plants. In fact, plant systems are becoming increasingly interesting for space adaptation studies, being useful not only as food source but also as sink of bioactive molecules in future bioregenerative life-support systems (BLSS). However, the application of protective magnetic shields would generate inside space habitats residual magnetic fields, of the order of few hundreds milli Tesla, whose effect on plant systems is poorly known. To simulate the exposure conditions of these residual magnetic fields in shielded environment, devices generating high-intensity static magnetic field (SMF) were comparatively evaluated in blind exposure experiments (250 mT, 500 mT and sham -no SMF-). The effects of these SMFs were assayed on tomato cultures (hairy roots) previously engineered to produce anthocyanins, known for their anti-oxidant properties and possibly useful in the setting of BLSS. Hairy roots exposed for periods ranging from 24 h to 11 days were morphometrically analyzed to measure their growth and corresponding molecular changes were assessed by a differential proteomic approach. After disclosing blind exposure protocol, a stringent statistical elaboration revealed the absence of significant differences in the soluble proteome, perfectly matching phenotypic results. These experimental evidences demonstrate that the identified plant system well tolerates the exposure to these magnetic fields. Results hereby described reinforce the notion of using this plant organ culture as a tool in ground-based experiments simulating space and planetary environments, in a perspective of using tomato 'hairy root' cultures as bioreactor of ready-to-use bioactive molecules during future long-term space missions.

Online radiation dose measurement system for ATLAS experiment

International Nuclear Information System (INIS)

Mandic, I.; Cindro, V.; Dolenc, I.; Gorisek, A.; Kramberger, G.; Mikuz, M.; Bronner, J.; Hartet, J.; Franz, S.

2009-01-01

In experiments at Large Hadron Collider, detectors and electronics will be exposed to high fluxes of photons, charged particles and neutrons. Damage caused by the radiation will influence performance of detectors. It will therefore be important to continuously monitor the radiation dose in order to follow the level of degradation of detectors and electronics and to correctly predict future radiation damage. A system for online radiation monitoring using semiconductor radiation sensors at large number of locations has been installed in the ATLAS experiment. Ionizing dose in SiO 2 will be measured with RadFETs, displacement damage in silicon in units of 1-MeV(Si) equivalent neutron fluence with p-i-n diodes. At 14 monitoring locations where highest radiation levels are expected the fluence of thermal neutrons will be measured from current gain degradation in dedicated bipolar transistors. The design of the system and tests of its performance in mixed radiation field is described in this paper. First results from this test campaign confirm that doses can be measured with sufficient sensitivity (mGy for total ionizing dose measurements, 10 9 n/cm 2 for NIEL (non-ionizing energy loss) measurements, 10 12 n/cm 2 for thermal neutrons) and accuracy (about 20%) for usage in the ATLAS detector

/sup 1/H-NMR chemical shift imaging suitable for low field systems

Energy Technology Data Exchange (ETDEWEB)

Yamamoto, Etsuji; Onodera, Takashi; Shiono, Hidemi; Kohno, Hideki

1986-12-01

An echo-time encoding proton NMR chemical shift imaging proposed by Dixon is extended to be applicable to low filed systems. The method utilizes the small phase angle between magnetic vectors of water and lipid protons to decrease the signal decays with spin-spin relaxation. The inevitable phase error caused by the static field inhomogeneity is corrected by using phase images of phantom measured under the same conditions as the actual measurements. The experiments were carried out using CuSO/sub 4/ doped water and vegetable oil at 0.5 T. Two chemical shift images could be clearly resolved with only one scan when the field inhomogeneity was larger than the chemical shift difference.

Circuit modification in electrical field flow fractionation systems generating higher resolution separation of nanoparticles.

Science.gov (United States)

Tasci, Tonguc O; Johnson, William P; Fernandez, Diego P; Manangon, Eliana; Gale, Bruce K

2014-10-24

Compared to other sub-techniques of field flow fractionation (FFF), cyclical electrical field flow fractionation (CyElFFF) is a relatively new method with many opportunities remaining for improvement. One of the most important limitations of this method is the separation of particles smaller than 100nm. For such small particles, the diffusion rate becomes very high, resulting in severe reductions in the CyElFFF separation efficiency. To address this limitation, we modified the electrical circuitry of the ElFFF system. In all earlier ElFFF reports, electrical power sources have been directly connected to the ElFFF channel electrodes, and no alteration has been made in the electrical circuitry of the system. In this work, by using discrete electrical components, such as resistors and diodes, we improved the effective electric field in the system to allow high resolution separations. By modifying the electrical circuitry of the ElFFF system, high resolution separations of 15 and 40nm gold nanoparticles were achieved. The effects of applying different frequencies, amplitudes and voltage shapes have been investigated and analyzed through experiments. Copyright © 2014 Elsevier B.V. All rights reserved.

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.

Fast, large field-of-view, telecentric optical-CT scanning system for 3D radiochromic dosimetry

Energy Technology Data Exchange (ETDEWEB)

Thomas, A; Oldham, M, E-mail: ast5@duke.ed [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States)

2010-11-01

We describe initial experiences with an in-house, fast, large field-of-view optical-CT telecentric scanner (the Duke Large field of view Optical-CT Scanner (DLOS)). The DLOS system is designed to enable telecentric optical-CT imaging of dosimeters up to 24 cm in diameter with a spatial resolution of 1 mm{sup 3}, in approximately 10 minutes. These capabilities render the DLOS system a unique device at present. The system is a scaled up version of early prototypes in our lab. This scaling introduces several challenges, including the accurate measurement of a greatly increased range of light attenuation within the dosimeter, and the need to reduce even minor reflections and scattered light within the imaging chain. We present several corrections and techniques that enable accurate, low noise, 3D dosimetery with the DLOS system.

Management system for the SND experiments

International Nuclear Information System (INIS)

Pugachev, K.; Korol, A.

2017-01-01

A new management system for the SND detector experiments (at VEPP-2000 collider in Novosibirsk) is developed. We describe here the interaction between a user and the SND databases. These databases contain experiment configuration, conditions and metadata. The new system is designed in client-server architecture. It has several logical layers corresponding to the users roles. A new template engine is created. A web application is implemented using Node.js framework. At the time the application provides: showing and editing configuration; showing experiment metadata and experiment conditions data index; showing SND log (prototype).

Preference effects on friendship choice: Evidence from an online field experiment.

Science.gov (United States)

Yu, Siyu; Xie, Yu

2017-08-01

Observed friendship choices are constrained by social structures and thus problematic indicators for underlying personal preferences. In this paper, we report on a study demonstrating the causal effects of preference in friendship choice based on an online field experiment. Specifically, we tested two important forces that govern friendship choices: preference for shared group identity (operationalized as the desire to befriend others sharing the same place-of-origin identity) and preference for high status (operationalized as the desire to befriend others from high-status institutions). Using an online field experiment in one of the largest social network service websites in China, we investigated the causal preference effects of these two forces free from structural constraints. The results of our study confirm the preference effects on friendship choice in both of the two dimensions we tested. Copyright © 2017. Published by Elsevier Inc.

Evolution of Decision Support Systems Research Field in Numbers

Directory of Open Access Journals (Sweden)

Ana-Maria SUDUC

2010-01-01

Full Text Available The scientific production in a certain field shows, in great extent, the research interests in that field. Decision Support Systems are a particular class of information systems which are gaining more popularity in various domains. In order to identify the evolution in time of the publications number, authors, subjects, publications in the Decision Support Systems (DSS field, and therefore the scientific world interest for this field, in November 2010 there have been organized a series of queries on three major international scientific databases: ScienceDirect, IEEE Xplore Digital Library and ACM Digital Library. The results presented in this paper shows that, even the decision support systems research field started in 1960s, the interests for this type of systems grew exponentially with each year in the last decades.

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…

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.)

Software complex AS (automation of spectrometry). User interface of experiment automation system implementation

International Nuclear Information System (INIS)

Astakhova, N.V.; Beskrovnyj, A.I.; Bogdzel', A.A.; Butorin, P.E.; Vasilovskij, S.G.; Gundorin, N.A.; Zlokazov, V.B.; Kutuzov, S.A.; Salamatin, I.M.; Shvetsov, V.N.

2003-01-01

An instrumental software complex for automation of spectrometry (AS) that enables prompt realization of experiment automation systems for spectrometers, which use data buferisation, has been developed. In the development new methods of programming and building of automation systems together with novel net technologies were employed. It is suggested that programs to schedule and conduct experiments should be based on the parametric model of the spectrometer, the approach that will make it possible to write programs suitable for any FLNP (Frank Laboratory of Neutron Physics) spectrometer and experimental technique applied and use different hardware interfaces for introducing the spectrometric data into the data acquisition system. The article describes the possibilities provided to the user in the field of scheduling and control of the experiment, data viewing, and control of the spectrometer parameters. The possibility of presenting the current spectrometer state, programs and the experimental data in the Internet in the form of dynamically formed protocols and graphs, as well as of the experiment control via the Internet is realized. To use the means of the Internet on the side of the client, applied programs are not needed. It suffices to know how to use the two programs to carry out experiments in the automated mode. The package is designed for experiments in condensed matter and nuclear physics and is ready for using. (author)

An investigation of singular Lagrangians as field systems

International Nuclear Information System (INIS)

Rabei, E.M.

1995-07-01

The link between the treatment of singular Lagrangians as field systems and the general approach is studied. It is shown that singular Lagrangians as field systems are always in exact agreement with the general approach. Two examples and the singular Lagrangian with zero rank Hessian matrix are studied. The equations of motion in the field systems are equivalent to the equations which contain acceleration, and the constraints are equivalent to the equations which do not contain acceleration in the general approach treatment. (author). 10 refs

Earth analog image digitization of field, aerial, and lab experiment studies for Planetary Data System archiving.

Science.gov (United States)

Williams, D. A.; Nelson, D. M.

2017-12-01

A portion of the earth analog image archive at the Ronald Greeley Center for Planetary Studies (RGCPS)-the NASA Regional Planetary Information Facility at Arizona State University-is being digitized and will be added to the Planetary Data System (PDS) for public use. This will be a first addition of terrestrial data to the PDS specifically for comparative planetology studies. Digitization is separated into four tasks. First is the scanning of aerial photographs of volcanic and aeolian structures and flows. The second task is to scan field site images taken from ground and low-altitude aircraft of volcanic structures, lava flows, lava tubes, dunes, and wind streaks. The third image set to be scanned includes photographs of lab experiments from the NASA Planetary Aeolian Laboratory wind tunnels, vortex generator, and of wax models. Finally, rare NASA documents are being scanned and formatted as PDF files. Thousands of images are to be scanned for this project. Archiving of the data will follow the PDS4 standard, where the entire project is classified as a single bundle, with individual subjects (i.e., the Amboy Crater volcanic structure in the Mojave Desert of California) as collections. Within the collections, each image is considered a product, with a unique ID and associated XML document. Documents describing the image data, including the subject and context, will be included with each collection. Once complete, the data will be hosted by a PDS data node and available for public search and download. As one of the first earth analog datasets to be archived by the PDS, this project could prompt the digitizing and making available of historic datasets from other facilities for the scientific community.

Measurements with magnetic field in the National Spherical Torus Experiment using the motional Stark effect with laser induced fluorescence diagnostic

Energy Technology Data Exchange (ETDEWEB)

Foley, E. L.; Levinton, F. M. [Nova Photonics, Inc., Princeton, New Jersey 08540 (United States)

2013-04-15

The motional Stark effect with laser-induced fluorescence diagnostic (MSE-LIF) has been installed and tested on the National Spherical Torus Experiment (NSTX) at the Princeton Plasma Physics Lab. The MSE-LIF diagnostic will be capable of measuring radially resolved profiles of magnetic field magnitude or pitch angle in NSTX plasmas. The system includes a diagnostic neutral hydrogen beam and a laser which excites the n = 2 to n = 3 transition. A viewing system has been implemented which will support up to 38 channels from the plasma edge to past the magnetic axis. First measurements of MSE-LIF signals in the presence of small applied magnetic fields in neutral gas are reported.

Measurements with magnetic field in the National Spherical Torus Experiment using the motional Stark effect with laser induced fluorescence diagnostic

Science.gov (United States)

Foley, E. L.; Levinton, F. M.

2013-04-01

The motional Stark effect with laser-induced fluorescence diagnostic (MSE-LIF) has been installed and tested on the National Spherical Torus Experiment (NSTX) at the Princeton Plasma Physics Lab. The MSE-LIF diagnostic will be capable of measuring radially resolved profiles of magnetic field magnitude or pitch angle in NSTX plasmas. The system includes a diagnostic neutral hydrogen beam and a laser which excites the n = 2 to n = 3 transition. A viewing system has been implemented which will support up to 38 channels from the plasma edge to past the magnetic axis. First measurements of MSE-LIF signals in the presence of small applied magnetic fields in neutral gas are reported.

Assessment of Habitat Suitability Is Affected by Plant-Soil Feedback: Comparison of Field and Garden Experiment.

Directory of Open Access Journals (Sweden)

Lucie Hemrová

Full Text Available Field translocation experiments (i.e., the introduction of seeds or seedlings of different species into different localities are commonly used to study habitat associations of species, as well as factors limiting species distributions and local abundances. Species planted or sown in sites where they naturally occur are expected to perform better or equally well compared to sites at which they do not occur or are rare. This, however, contrasts with the predictions of the Janzen-Connell hypothesis and commonly reported intraspecific negative plant-soil feedback. The few previous studies indicating poorer performance of plants at sites where they naturally occur did not explore the mechanisms behind this pattern.In this study, we used field translocation experiments established using both seeds and seedlings to study the determinants of local abundance of four dominant species in grasslands. To explore the possible effects of intraspecific negative plant-soil feedback on our results, we tested the effect of local species abundance on the performance of the plants in the field experiment. In addition, we set up a garden experiment to explore the intensity of intraspecific as well as interspecific feedback between the dominants used in the experiment.In some cases, the distribution and local abundances of the species were partly driven by habitat conditions at the sites, and species performed better at their own sites. However, the prevailing pattern was that the local dominants performed worse at sites where they naturally occur than at any other sites. Moreover, the success of plants in the field experiment was lower in the case of higher intraspecific abundance prior to experimental setup. In the garden feedback experiment, two of the species performed significantly worse in soils conditioned by their species than in soils conditioned by the other species. In addition, the performance of the plants was significantly correlated between the two

A high-resolution full-field range imaging system

Science.gov (United States)

Carnegie, D. A.; Cree, M. J.; Dorrington, A. A.

2005-08-01

There exist a number of applications where the range to all objects in a field of view needs to be obtained. Specific examples include obstacle avoidance for autonomous mobile robots, process automation in assembly factories, surface profiling for shape analysis, and surveying. Ranging systems can be typically characterized as being either laser scanning systems where a laser point is sequentially scanned over a scene or a full-field acquisition where the range to every point in the image is simultaneously obtained. The former offers advantages in terms of range resolution, while the latter tend to be faster and involve no moving parts. We present a system for determining the range to any object within a camera's field of view, at the speed of a full-field system and the range resolution of some point laser scans. Initial results obtained have a centimeter range resolution for a 10 second acquisition time. Modifications to the existing system are discussed that should provide faster results with submillimeter resolution.

Energy field of thermodynamic syste'ms

International Nuclear Information System (INIS)

Volchenkova, R.A.

1984-01-01

To reveal the qualitative and quantitative rules, regulating the properties of macro- and microsystems consideration is being given to the dependence of system enthalpy on environmental conditions. It was concluded that the dependence of material system enthalpy on temperature represents the energy field, containing the energy boundaries of phase states, described by exponential functions, in which the elements are arranged monotonically in the sequence of change of interatomic bonds, correlated with their physicomechanical properties; energy boundaries of phase states at that emanate from a single point, which is a reference a single point, which a reference one for the whole material system and determining its energy state in initial position. The presented energy field of thermodynamic systems enables to consider the change of their physicomechanical properties and energy state in dynamic process, depending on environmental parameters. Energy characteristics of single-component systems (W, Re, Hf, Nb, Mo etc) are given

CRISP. D3.3. Final report on field experiments and tests

International Nuclear Information System (INIS)

Warmer, C.J.; Kamphuis, I.G.; Gustavsson, R.; Andrieu, C.

2006-06-01

This document describes the high level results of the three field experiments and tests performed within the CRISP project. The aims of the document are: To give an account of the lessons learned from the experiments as they have been performed; To give recommendations for strategic use of intelligent ICT in high-DG power networks (thinking forward from our experience in the experiments); and To compile 'industrial guidelines and recommendations' for the strategic use of intelligent ICT for various operational aspects of high-DG power networks. These strategic recommendations will not only cover technology issues, but also business, economic, and market considerations. The role of utilities and third parties in utilising this new technology in this changing scene forms an important issue to be dealt with

Searching for Authentic Context in Designing PISA-like Mathematics Problem: From Indoor to Outdoor Field Experience

Science.gov (United States)

Siswono, T. Y. E.; Kohar, A. W.; Rosyidi, A. H.; Hartono, S.; Masriyah

2018-01-01

Designing problem like in PISA is known as a challenging activity for teachers particularly as the use of authentic context within that type of problem. This paper aims to describe the experiences of secondary mathematics teachers in designing PISA-like problems within an innovative training program focusing on building teachers’ understanding on the concept of mathematical literacy. The teachers were engaged in a set of problem-solving and problem-posing activities using PISA-based problem within indoor and outdoor field experiences. Within indoor field experience, the teachers worked collaboratively in groups on designing PISA-like problems with a given context through problem generation and reformulation techniques. Within outdoor field experience, they worked on designing PISA-like problems with self-chosen context from the place where the outdoor field experience took place. Our analysis indicates that there were improvements on the PISA-like problems designed by teachers based on its level use of context from indoor to outdoor experience. Also, the teachers were relatively successful with creating appropriate and motivating contexts by harnessing a variety of context consisting of personal, occupational, societal, and scientific contexts. However, they still experienced difficulties in turning these contexts into an appropriate problem satisfying PISA framework such as regarding authenticity of context use, language structure, and PISA task profile.

Analysis of biostimulated microbial communities from two field experiments reveals temporal and spatial differences in proteome profiles

Energy Technology Data Exchange (ETDEWEB)

Callister, S.J.; Wilkins, M.J.; Nicora, C.D.; Williams, K.H.; Banfield, J.F.; VerBerkmoes, N.C.; Hettich, R.L.; NGuessan, A.L.; Mouser, P.J.; Elifantz, H.; Smith, R.D.; Lovley, D.R.; Lipton, M.S.; Long, P.E.

2010-07-15

Stimulated by an acetate-amendment field experiment conducted in 2007, anaerobic microbial populations in the aquifer at the Rifle Integrated Field Research Challenge site in Colorado reduced mobile U(VI) to insoluble U(IV). During this experiment, planktonic biomass was sampled at various time points to quantitatively evaluate proteomes. In 2008, an acetate-amended field experiment was again conducted in a similar manner to the 2007 experiment. As there was no comprehensive metagenome sequence available for use in proteomics analysis, we systematically evaluated 12 different organism genome sequences to generate sets of aggregate genomes, or “pseudo-metagenomes”, for supplying relative quantitative peptide and protein identifications. Proteomics results support previous observations of the dominance of Geobacteraceae during biostimulation using acetate as sole electron donor, and revealed a shift from an early stage of iron reduction to a late stage of iron reduction. Additionally, a shift from iron reduction to sulfate reduction was indicated by changes in the contribution of proteome information contributed by different organism genome sequences within the aggregate set. In addition, the comparison of proteome measurements made between the 2007 field experiment and 2008 field experiment revealed differences in proteome profiles. These differences may be the result of alterations in abundance and population structure within the planktonic biomass samples collected for analysis.

Pulsed zero field NMR of solids and liquid crystals

International Nuclear Information System (INIS)

Thayer, A.M.

1987-02-01

This work describes the development and applications to solids and liquid crystals of zero field nuclear magnetic resonance (NMR) experiments with pulsed dc magnetic fields. Zero field NMR experiments are one approach for obtaining high resolution spectra of amorphous and polycrystalline materials which normally (in high field) display broad featureless spectra. The behavior of the spin system can be coherently manipulated and probed in zero field with dc magnetic field pulses which are employed in a similar manner to radiofrequency pulses in high field NMR experiments. Nematic phases of liquid crystalline systems are studied in order to observe the effects of the removal of an applied magnetic field on sample alignment and molecular order parameters. In nematic phases with positive and negative magnetic susceptibility anisotropies, a comparison between the forms of the spin interactions in high and low fields is made. High resolution zero field NMR spectra of unaligned smectic samples are also obtained and reflect the symmetry of the liquid crystalline environment. These experiments are a sensitive measure of the motionally induced asymmetry in biaxial phases. Homonuclear and heteronuclear solute spin systems are compared in the nematic and smectic phases. Nonaxially symmetric dipolar couplings are reported for several systems. The effects of residual fields in the presence of a non-zero asymmetry parameter are discussed theoretically and presented experimentally. Computer programs for simulations of these and other experimental results are also reported. 179 refs., 75 figs

Inhibition of two-photon absorption in a three-level system with a pair of bichromatic fields

International Nuclear Information System (INIS)

Zou Jinhua; Hu Xiangming; Cheng Guangling; Li Xing; Du Dan

2005-01-01

We study two-photon absorption in a three-level ladder atomic system driven by a pair of bichromatic fields of equal frequency differences. The high-frequency component of one bichromatic field and the low-frequency component of the other are on two-photon resonance. The transition probability is calculated by employing the method of harmonic expansion and matrix inversion. Unexpectedly, when the sums of the phases of the different pairs of field components on the two-photon resonance are equal to each other, two-photon absorption is dramatically suppressed and the atomic system becomes transparent against two-photon absorption. Physically, due to dynamical Stark splitting, the two-photon transitions induced by the different pairs of field components experience different dressed states with phase difference of π. As a result, destructive interference occurs between the two pathways and leads to the inhibition of two-photon absorption

Data from the Hot Serial Cereal Experiment for modeling wheat response to temperature: field experiments and AgMIP-Wheat multi-model simulations

NARCIS (Netherlands)

Martre, Pierre; Kimball, Bruce A.; Ottman, Michael J.; Wall, Gerard W.; White, Jeffrey W.; Asseng, Senthold; Ewert, Frank; Cammarano, Davide; Maiorano, Andrea; Aggarwal, Pramod K.; Supit, I.; Wolf, J.

2018-01-01

The dataset reported here includes the part of a Hot Serial Cereal Experiment (HSC) experiment recently used in the AgMIP-Wheat project to analyze the uncertainty of 30 wheat models and quantify their response to temperature. The HSC experiment was conducted in an open-field in a semiarid

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)

Field-induced phase transition in a metalorganic spin-dimer system-a potential model system to study Bose-Einstein condensation of magnons

International Nuclear Information System (INIS)

Tsui, Y.; Bruehl, A.; Removic-Langer, K.; Pashchenko, V.; Wolf, B.; Donath, G.; Pikul, A.; Kretz, T.; Lerner, H.-W.; Wagner, M.; Salguero, A.; Saha-Dasgupta, T.; Rahaman, B.; Valenti, R.; Lang, M.

2007-01-01

We report on the results obtained from studying electron spin resonance, magnetic susceptibility, specific heat and thermal expansion experiments on a metalorganic spin-dimer system, C 36 H 48 Cu 2 F 6 N 8 O 12 S 2 (TK91). According to the first principle Density Functional Theory calculations, the compound represents a 3D-coupled dimer system with intradimer coupling J 1 /k B ∼ 10K and interdimer couplings J 2 /k B ∼J 3 /k B ∼ 1K. The measurements have been performed on both pressed powder and single-crystal samples in external magnetic fields up to 12T and at low temperatures down to ∼ 0.2K. Susceptibility measurements reveal a spin-gap behavior consistent with the theoretical results. Furthermore, clear indications of a field-induced phase transition have been observed. A similar field-induced phase transition was also detected in an inorganic compound TlCuCl 3 and was interpreted as Bose-Einstein condensation (BEC) of magnons. The possibility of changing both the intradimer and interdimer couplings in TK91 by chemical substitutions makes the system a potentially good system to study BEC of magnons

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...

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

Design and construction status of the energy system for the ZTH experiment

International Nuclear Information System (INIS)

Boenig, H.J.; Gribble, R.F.; Melton, J.G.

1989-01-01

A large scale reversed-field pinch fusion experiment, called ZTH, is being designed and built at Los Alamos. Initially, the machine will be operating at a 1.7 MA plasma current, however, the machine can be upgraded to a 4 MA current with many of the components, such as the torus, coil system and electrical power source already having the 4 MA capability. The first plasma discharges are expected to take place in the spring of 1993. Major electrical power equipment components, such as a 1430 MVA generator, controlled power supplies, isolation and opening switches, current interrupter, capacitor banks and transfer resistor are being designed and procured for this experiment. The design philosophy of the electrical system is explained. Test results of in-house research are described and the procurement status of the major components are summarized. 6 refs., 2 figs

Event Recording Data Acquisition System and Experiment Data Management System for Neutron Experiments at MLF, J-PARC

Science.gov (United States)

Nakatani, T.; Inamura, Y.; Moriyama, K.; Ito, T.; Muto, S.; Otomo, T.

Neutron scattering can be a powerful probe in the investigation of many phenomena in the materials and life sciences. The Materials and Life Science Experimental Facility (MLF) at the Japan Proton Accelerator Research Complex (J-PARC) is a leading center of experimental neutron science and boasts one of the most intense pulsed neutron sources in the world. The MLF currently has 18 experimental instruments in operation that support a wide variety of users from across a range of research fields. The instruments include optical elements, sample environment apparatus and detector systems that are controlled and monitored electronically throughout an experiment. Signals from these components and those from the neutron source are converted into a digital format by the data acquisition (DAQ) electronics and recorded as time-tagged event data in the DAQ computers using "DAQ-Middleware". Operating in event mode, the DAQ system produces extremely large data files (˜GB) under various measurement conditions. Simultaneously, the measurement meta-data indicating each measurement condition is recorded in XML format by the MLF control software framework "IROHA". These measurement event data and meta-data are collected in the MLF common storage and cataloged by the MLF Experimental Database (MLF EXP-DB) based on a commercial XML database. The system provides a web interface for users to manage and remotely analyze experimental data.

Steam generator waterlancing at Darlington NGS (system development and field application)

International Nuclear Information System (INIS)

Seppala, D.; Malaugh, J.; Kiisel, E.; Kamler, F.

1996-01-01

From the initial steam generator (SG) inspections at Darlington Nuclear Generating Station (DNGS), the authors know that the sludge accumulations on the secondary side tubesheets have been minimal. DNGS is a fairly new station but the experience at the older Ontario Hydro plants have shown that significant accumulations will happen. A pro-active strategy has been adopted for maintaining SGs that will minimize corrosion product accumulation and the potential for component degradation. During the four year planned Unit maintenance outages, SGs will be inspected and waterlanced using a waterlance system designed and built by Babcock and Wilcox International. This automated state-of-the-art system also allows fully recorded inspections of the tubesheet/first half-lattice supports. Some of the key elements covered include results of the initial field application (May, 1995), system development and design, system qualification, cleaning performance, and lessons learned for future outages

Microsurgical robotic system for the deep surgical field: development of a prototype and feasibility studies in animal and cadaveric models.

Science.gov (United States)

Morita, Akio; Sora, Shigeo; Mitsuishi, Mamoru; Warisawa, Shinichi; Suruman, Katopo; Asai, Daisuke; Arata, Junpei; Baba, Shoichi; Takahashi, Hidechika; Mochizuki, Ryo; Kirino, Takaaki

2005-08-01

To enhance the surgeon's dexterity and maneuverability in the deep surgical field, the authors developed a master-slave microsurgical robotic system. This concept and the results of preliminary experiments are reported in this paper. The system has a master control unit, which conveys motion commands in six degrees of freedom (X, Y, and Z directions; rotation; tip flexion; and grasping) to two arms. The slave manipulator has a hanging base with an additional six degrees of freedom; it holds a motorized operating unit with two manipulators (5 mm in diameter, 18 cm in length). The accuracy of the prototype in both shallow and deep surgical fields was compared with routine freehand microsurgery. Closure of a partial arteriotomy and complete end-to-end anastomosis of the carotid artery (CA) in the deep operative field were performed in 20 Wistar rats. Three routine surgical procedures were also performed in cadavers. The accuracy of pointing with the nondominant hand in the deep surgical field was significantly improved through the use of robotics. The authors successfully closed the partial arteriotomy and completely anastomosed the rat CAs in the deep surgical field. The time needed for stitching was significantly shortened over the course of the first 10 rat experiments. The robotic instruments also moved satisfactorily in cadavers, but the manipulators still need to be smaller to fit into the narrow intracranial space. Computer-controlled surgical manipulation will be an important tool for neurosurgery, and preliminary experiments involving this robotic system demonstrate its promising maneuverability.

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...

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.

Development of wireless communication system in real-time internal radiation dose measurement system using magnetic field

International Nuclear Information System (INIS)

Sato, Fumihiro; Shinohe, Kohta; Takura, Tetsuya; Matsuki, Hidetoshi; Yamada, Syogo; Sato, Tadakuni

2009-01-01

In radiation therapy, excessive radiation occurs because the actual delivered dose to the tumor is unknown. To overcome this problem, we need a system in which the delivered dose is measured inside the body, and the dose data are transmitted from the inside to the outside of the body. In this study, a wireless communication system, using magnetic fields was studied, and an internal circuit for obtaining radiation dose data from an x-ray detector was examined. As a result, a communication distance of 200 mm was obtained. An internal circuit was developed, and a signal transmission experiment was performed using the wireless communication system. As a result, the radiation dose data from an x-ray detector was transmitted over a communication distance of 200 mm, and the delivered dose was determined from the received signal

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

Experiences with Ada in an embedded system

Science.gov (United States)

Labaugh, Robert J.

1988-01-01

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

Developing the Precision Magnetic Field for the E989 Muon g{2 Experiment

Energy Technology Data Exchange (ETDEWEB)

Smith, Matthias W. [Washington U., Seattle

2017-01-01

The experimental value of $(g\\hbox{--}2)_\\mu$ historically has been and contemporarily remains an important probe into the Standard Model and proposed extensions. Previous measurements of $(g\\hbox{--}2)_\\mu$ exhibit a persistent statistical tension with calculations using the Standard Model implying that the theory may be incomplete and constraining possible extensions. The Fermilab Muon g-2 experiment, E989, endeavors to increase the precision over previous experiments by a factor of four and probe more deeply into the tension with the Standard Model. The $(g\\hbox{--}2)_\\mu$ experimental implementation measures two spin precession frequencies defined by the magnetic field, proton precession and muon precession. The value of $(g\\hbox{--}2)_\\mu$ is derived from a relationship between the two frequencies. The precision of magnetic field measurements and the overall magnetic field uniformity achieved over the muon storage volume are then two undeniably important aspects of the e xperiment in minimizing uncertainty. The current thesis details the methods employed to achieve magnetic field goals and results of the effort.

Simulating the volatilization of solvents in unsaturated soils during laboratory and field infiltration experiments

Science.gov (United States)

Cho, H. Jean; Jaffe, Peter R.; Smith, James A.

1993-01-01

This paper describes laboratory and field experiments which were conducted to study the dynamics of trichloroethylene (TCE) as it volatilized from contaminated groundwater and diffused in the presence of infiltrating water through the unsaturated soil zone to the land surface. The field experiments were conducted at the Picatinny Arsenal, which is part of the United States Geological Survey Toxic Substances Hydrology Program. In both laboratory and field settings the gas and water phase concentrations of TCE were not in equilibrium during infiltration. Gas-water mass transfer rate constants were calibrated to the experimental data using a model in which the water phase was treated as two phases: a mobile water phase and an immobile water phase. The mass transfer limitations of a volatile organic compound between the gas and liquid phases were described explicitly in the model. In the laboratory experiment the porous medium was nonsorbing, and water infiltration rates ranged from 0.076 to 0.28 cm h−1. In the field experiment the water infiltration rate was 0.34 cm h−1, and sorption onto the soil matrix was significant. The laboratory-calibrated gas-water mass transfer rate constant is 3.3×10−4 h−1 for an infiltration rate of 0.076 cm h−1 and 1.4×10−3 h−1 for an infiltration rate of 0.28 cm h−1. The overall mass transfer rate coefficients, incorporating the contribution of mass transfer between mobile and immobile water phases and the variation of interfacial area with moisture content, range from 3×10−4 h−1 to 1×10−2 h−1. A power law model relates the gas-water mass transfer rate constant to the infiltration rate and the fraction of the water phase which is mobile. It was found that the results from the laboratory experiments could not be extrapolated to the field. In order to simulate the field experiment the very slow desorption of TCE from the soil matrix was incorporated into the mathematical model. When desorption from the

Quantum noise in the mirror–field system: A field theoretic approach

International Nuclear Information System (INIS)

Hsiang, Jen-Tsung; Wu, Tai-Hung; Lee, Da-Shin; King, Sun-Kun; Wu, Chun-Hsien

2013-01-01

We revisit the quantum noise problem in the mirror–field system by a field-theoretic approach. Here a perfectly reflecting mirror is illuminated by a single-mode coherent state of the massless scalar field. The associated radiation pressure is described by a surface integral of the stress-tensor of the field. The read-out field is measured by a monopole detector, from which the effective distance between the detector and mirror can be obtained. In the slow-motion limit of the mirror, this field-theoretic approach allows to identify various sources of quantum noise that all in all leads to uncertainty of the read-out measurement. In addition to well-known sources from shot noise and radiation pressure fluctuations, a new source of noise is found from field fluctuations modified by the mirror’s displacement. Correlation between different sources of noise can be established in the read-out measurement as the consequence of interference between the incident field and the field reflected off the mirror. In the case of negative correlation, we found that the uncertainty can be lowered than the value predicted by the standard quantum limit. Since the particle-number approach is often used in quantum optics, we compared results obtained by both approaches and examine its validity. We also derive a Langevin equation that describes the stochastic dynamics of the mirror. The underlying fluctuation–dissipation relation is briefly mentioned. Finally we discuss the backreaction induced by the radiation pressure. It will alter the mean displacement of the mirror, but we argue this backreaction can be ignored for a slowly moving mirror. - Highlights: ► The quantum noise problem in the mirror–field system is re-visited by a field-theoretic approach. ► Other than the shot noise and radiation pressure noise, we show there are new sources of noise and correlation between them. ► The noise correlations can be used to suppress the overall quantum noise on the mirror. �

Quantum noise in the mirror-field system: A field theoretic approach

Energy Technology Data Exchange (ETDEWEB)

Hsiang, Jen-Tsung, E-mail: cosmology@gmail.com [Department of Physics, National Dong-Hwa University, Hua-lien, Taiwan, ROC (China); Wu, Tai-Hung [Department of Physics, National Dong-Hwa University, Hua-lien, Taiwan, ROC (China); Lee, Da-Shin, E-mail: dslee@mail.ndhu.edu.tw [Department of Physics, National Dong-Hwa University, Hua-lien, Taiwan, ROC (China); King, Sun-Kun [Institutes of Astronomy and Astrophysics, Academia Sinica, Taipei, Taiwan, ROC (China); Wu, Chun-Hsien [Department of Physics, Soochow University, Taipei, Taiwan, ROC (China)

2013-02-15

We revisit the quantum noise problem in the mirror-field system by a field-theoretic approach. Here a perfectly reflecting mirror is illuminated by a single-mode coherent state of the massless scalar field. The associated radiation pressure is described by a surface integral of the stress-tensor of the field. The read-out field is measured by a monopole detector, from which the effective distance between the detector and mirror can be obtained. In the slow-motion limit of the mirror, this field-theoretic approach allows to identify various sources of quantum noise that all in all leads to uncertainty of the read-out measurement. In addition to well-known sources from shot noise and radiation pressure fluctuations, a new source of noise is found from field fluctuations modified by the mirror's displacement. Correlation between different sources of noise can be established in the read-out measurement as the consequence of interference between the incident field and the field reflected off the mirror. In the case of negative correlation, we found that the uncertainty can be lowered than the value predicted by the standard quantum limit. Since the particle-number approach is often used in quantum optics, we compared results obtained by both approaches and examine its validity. We also derive a Langevin equation that describes the stochastic dynamics of the mirror. The underlying fluctuation-dissipation relation is briefly mentioned. Finally we discuss the backreaction induced by the radiation pressure. It will alter the mean displacement of the mirror, but we argue this backreaction can be ignored for a slowly moving mirror. - Highlights: Black-Right-Pointing-Pointer The quantum noise problem in the mirror-field system is re-visited by a field-theoretic approach. Black-Right-Pointing-Pointer Other than the shot noise and radiation pressure noise, we show there are new sources of noise and correlation between them. Black-Right-Pointing-Pointer The noise

Conceptual design of a digital control system for nuclear criticality experiments

International Nuclear Information System (INIS)

Rojas, S.P.

1994-04-01

Nuclear criticality is a concern in many areas of nuclear engineering including waste management, nuclear weapons testing and design, basic nuclear research, and nuclear reactor design and analysis. As in many areas of science and engineering, experimental work conducted in this field has provided a wealth of data and insight essential to the formulation of theory and the advancement in knowledge of fissioning systems. In light of the many diverse applications of nuclear criticality, there is a continuing interest to learn and understand more about the fundamental physical processes through continued experimentation. This thesis addresses the problem of setting up and programming a microprocessor-based digital control system (PLC) for a proposed critical experiment using, among other devices, a stepper motor, a joystick control mechanism, and switches. This experiment represents a revised configuration to test cylindrical nuclear waste packages. A Monte Carlo numerical study for the proposed critical assembly has been performed in order to illustrate how results from numerical calculations are used in the process of assembling the control system and to corroborate previous experimental data. In summary, a control system utilizing some common devices necessary to perform a critical experiment (stepper motor, push-buttons, etc.) has been assembled. Control components were sized using the results of a probabilistic computer code (MCNP). Finally, a program was written that illustrates the coupling between the hardware and the devices being controlled in the new test fixture

Quantum field theory in stationary coordinate systems

International Nuclear Information System (INIS)

Pfautsch, J.D.

1981-01-01

Quantum field theory is examined in stationary coordinate systems in Minkowski space. Preliminary to quantization of the scalar field, all of the possible stationary coordinate systems in flat spacetime are classified and explicitly constructed. Six distinct classes of such systems are found. Of these six, three have (identical) event horizons associated with them and five have Killing horizons. Two classes have distinct Killing and event horizons, with an intervening region analogous to the ergosphere in rotating black holes. Particular representatives of each class are selected for subsequent use in the quantum field theory. The scalar field is canonically quantized and a vacuum defined in each of the particular coordinate systems chosen. The vacuum states can be regarded as adapted to the six classes of stationary motions. There are only two vacuum states found, the Minkowski vacuum in those coordinate systems without event horizons and the Fulling vacuum in those with event horizons. The responses of monopole detectors traveling along stationary world lines are calculated in both the Minkowski and Fulling vacuums. The responses for each class of motions are distinct from those for every other class. A vacuum defined by the response of a detector must therefore not be equivalent in general to a vacuum defined by canonical quantization. Quantization of the scalar field within a rotating wedge is examined. It has not been possible to construct mode functions satisfying appropriate boundary conditions on the surface of the wedge. The asymptotic form of the renormalized stress tensor near the surfaces had been calculated and is found to include momentum terms which represent a circulation of energy within the wedge

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.

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.

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.

The origin of fluctuations and cross-field transport in idealized magnetic confinement systems

International Nuclear Information System (INIS)

Riviere, A.C.; Ashby, D.E.T.F.; Cordey, J.G.; Edlington, T.; Rusbridge, M.G.

1981-01-01

The study of plasma fluctuations and confinement in idealized systems such as octupoles and levitrons has contributed to the understanding of cross-field transport processes. The linear theory of plasma instabilities that cause fluctuations can predict growth rates and wavelengths around lines of force. However, the theoretical prediction of cross-field transport coefficient is restricted to quasilinear estimates which usually far exceed the measured values. A general view of the results from octupole and levitron experiments shows that under collisional conditions the diffusion coefficient scales in the same way as classical collisional diffusion. Agreement is closely approached in many cases, sometimes even in the presence of fluctuations. Under collisionless conditions, Bohm diffusion scaling is found in the few cases where the scaling law has been determined. There is also experimental and theoretical evidence that long-wavelength low-frequency electric fields (convection cells) can be generated nonlinearly from high-frequency fluctuations and can contribute to cross-field transport. (author)

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)

Online radiation dose measurement system for ATLAS experiment

Energy Technology Data Exchange (ETDEWEB)

Mandic, I.; Cindro, V.; Dolenc, I.; Gorisek, A.; Kramberger, G. [Jozef Stefan Institute, Jamova 39, Ljubljana (Slovenia); Mikuz, M. [Jozef Stefan Institute, Jamova 39, Ljubljana (Slovenia); Faculty of Mathematics and Physics, University of Ljubljana (Slovenia); Bronner, J.; Hartet, J. [Physikalisches Institut, Universitat Freiburg, Hermann-Herder-Str. 3, Freiburg (Germany); Franz, S. [CERN, Geneva (Switzerland)

2009-07-01

In experiments at Large Hadron Collider, detectors and electronics will be exposed to high fluxes of photons, charged particles and neutrons. Damage caused by the radiation will influence performance of detectors. It will therefore be important to continuously monitor the radiation dose in order to follow the level of degradation of detectors and electronics and to correctly predict future radiation damage. A system for online radiation monitoring using semiconductor radiation sensors at large number of locations has been installed in the ATLAS experiment. Ionizing dose in SiO{sub 2} will be measured with RadFETs, displacement damage in silicon in units of 1-MeV(Si) equivalent neutron fluence with p-i-n diodes. At 14 monitoring locations where highest radiation levels are expected the fluence of thermal neutrons will be measured from current gain degradation in dedicated bipolar transistors. The design of the system and tests of its performance in mixed radiation field is described in this paper. First results from this test campaign confirm that doses can be measured with sufficient sensitivity (mGy for total ionizing dose measurements, 10{sup 9} n/cm{sup 2} for NIEL (non-ionizing energy loss) measurements, 10{sup 12} n/cm{sup 2} for thermal neutrons) and accuracy (about 20%) for usage in the ATLAS detector

Modeling Magnetospheric Fields in the Jupiter System

OpenAIRE

Saur, Joachim; Chané, Emmanuel; Hartkorn, Oliver

2018-01-01

The various processes which generate magnetic fields within the Jupiter system are exemplary for a large class of similar processes occurring at other planets in the solar system, but also around extrasolar planets. Jupiter’s large internal dynamo magnetic field generates a gigantic magnetosphere, which in contrast to Earth’s magnetosphere is strongly rotational driven and possesses large plasma sources located deeply within the magnetosphere. The combination of the latter two effects is the ...

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.

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…

Magnetic field induced flow pattern reversal in a ferrofluidic Taylor-Couette system.

Science.gov (United States)

Altmeyer, Sebastian; Do, Younghae; Lai, Ying-Cheng

2015-12-21

We investigate the dynamics of ferrofluidic wavy vortex flows in the counter-rotating Taylor-Couette system, with a focus on wavy flows with a mixture of the dominant azimuthal modes. Without external magnetic field flows are stable and pro-grade with respect to the rotation of the inner cylinder. More complex behaviors can arise when an axial or a transverse magnetic field is applied. Depending on the direction and strength of the field, multi-stable wavy states and bifurcations can occur. We uncover the phenomenon of flow pattern reversal as the strength of the magnetic field is increased through a critical value. In between the regimes of pro-grade and retrograde flow rotations, standing waves with zero angular velocities can emerge. A striking finding is that, under a transverse magnetic field, a second reversal in the flow pattern direction can occur, where the flow pattern evolves into pro-grade rotation again from a retrograde state. Flow reversal is relevant to intriguing phenomena in nature such as geomagnetic reversal. Our results suggest that, in ferrofluids, flow pattern reversal can be induced by varying a magnetic field in a controlled manner, which can be realized in laboratory experiments with potential applications in the development of modern fluid devices.

Field work in geography. Region with experience in socio-environmental conflicts

Directory of Open Access Journals (Sweden)

Beatriz Ensabella

2016-07-01

Full Text Available This article emphasizes the importance of the geographical field work in a region with socio-environmental conflict, such us the problem with water in Sierras Chicas, Cordoba. The main focus is a pedagogical experience, the Socio-Communal Practice (SCP, performed by professors, students and assistants of the subject Rural Geography, of the Bachelor’s in Geography course of studies of the Philosophy and Humanity School (PHS, in the city of La Granja, in Colón, Córdoba. The SCP is an experience that makes the students approach the social field of the territory conflicts. It is an activity that goes beyond the extension project, since it involves all the students doing the subject. And it is also a way to combine -in our case, from the geographic work- the teaching, investigation and extension functions typical of the university students. Through the SCP, we aim to make the Rural Geography students approach the field work, with local social organizations that deeply know the problems of their cities and that work together with our investigation group. In addition, this contact together with the individual thoughts, the group discussion and the debates between the university students, will broaden, in the whole society, the knowledge about the reality in which they live and with which they struggle. This article starts by defining what it is understood by SCP. Then, taking into account our practice, we develop what we consider to be the two logics that support the field work. One refers to the building of knowledge and to the different ways of learning and knowing. The other is related to the understanding of the socio-territory conflict in the area where the practice will be done: the Mesa del Agua and La Granja environment. We include a section about the description of the experience and its results, and we conclude with some reflections made taking into account the continuity of the practice

Experiments on melting in classical and quantum two dimensional electron systems

International Nuclear Information System (INIS)

Williams, F.I.B.

1991-01-01

''Two dimensional electron system'' (2DES) here refers to electrons whose dynamics is free in 2 dimensions but blocked in the third. Experiments have been performed in two limiting situations: the classical, low density, limit realised by electrons deposited on a liquid helium surface and the quantum, high density, limit realised by electrons at an interface between two epitaxially matched semiconductors. In the classical system, where T Q c so that the thermodynamic state is determined by the competition between the temperature and the Coulomb interaction, melting is induced either by raising the temperature at constant density or by lowering the density at finite temperature. In the quantum system, it is not possible to lower the density below about 100n W without the Coulomb interaction losing out to the random field representing the extrinsic disorder imposed by the semiconductor host. Instead one has to induce crystallisation with the help of the Lorentz force, by applying a perpendicular magnetic field B [2] . As the quantum magnetic length l c = (Planck constant c/eB) 1/2 is reduced with respect to the interelectronic spacing a, expressed by the filling factor ν 2l c 2 /a 2 , the system exhibits the quantum Hall effect (QHE), first for integer then for fractional values of ν. The fractional quantum Hall effect (FQHE) is a result of Coulomb induced correlation in the quantum liquid, but as ν is decreased still further the correlations are expected to take on long-range crystal-like periodicity accompanied by elastic shear rigidity. Such a state can nonetheless be destroyed by the disordering effect of temperature, giving rise to a phase boundary in a (T, B) plane. The aim of experiment is first to determine the phase diagram and then to help elucidate the mechanism of the melting. (author)

Estimating adhesive seed-dispersal distances : field experiments and correlated random walks

NARCIS (Netherlands)

Mouissie, AM; Lengkeek, W; van Diggelen, R

1. In this study we aimed to estimate distance distributions of adhesively dispersed seeds and the factors that determine them. 2. Seed attachment and detachment were studied using field experiments with a real sheep, a sheep dummy and a cattle dummy. Seed-retention data were used in correlated

Design of Field Experiments for Adaptive Sampling of the Ocean with Autonomous Vehicles

Science.gov (United States)

Zheng, H.; Ooi, B. H.; Cho, W.; Dao, M. H.; Tkalich, P.; Patrikalakis, N. M.

2010-05-01

Due to the highly non-linear and dynamical nature of oceanic phenomena, the predictive capability of various ocean models depends on the availability of operational data. A practical method to improve the accuracy of the ocean forecast is to use a data assimilation methodology to combine in-situ measured and remotely acquired data with numerical forecast models of the physical environment. Autonomous surface and underwater vehicles with various sensors are economic and efficient tools for exploring and sampling the ocean for data assimilation; however there is an energy limitation to such vehicles, and thus effective resource allocation for adaptive sampling is required to optimize the efficiency of exploration. In this paper, we use physical oceanography forecasts of the coastal zone of Singapore for the design of a set of field experiments to acquire useful data for model calibration and data assimilation. The design process of our experiments relied on the oceanography forecast including the current speed, its gradient, and vorticity in a given region of interest for which permits for field experiments could be obtained and for time intervals that correspond to strong tidal currents. Based on these maps, resources available to our experimental team, including Autonomous Surface Craft (ASC) are allocated so as to capture the oceanic features that result from jets and vortices behind bluff bodies (e.g., islands) in the tidal current. Results are summarized from this resource allocation process and field experiments conducted in January 2009.

Real-time object tracking system based on field-programmable gate array and convolution neural network

Directory of Open Access Journals (Sweden)

Congyi Lyu

2016-12-01

Full Text Available Vision-based object tracking has lots of applications in robotics, like surveillance, navigation, motion capturing, and so on. However, the existing object tracking systems still suffer from the challenging problem of high computation consumption in the image processing algorithms. The problem can prevent current systems from being used in many robotic applications which have limitations of payload and power, for example, micro air vehicles. In these applications, the central processing unit- or graphics processing unit-based computers are not good choices due to the high weight and power consumption. To address the problem, this article proposed a real-time object tracking system based on field-programmable gate array, convolution neural network, and visual servo technology. The time-consuming image processing algorithms, such as distortion correction, color space convertor, and Sobel edge, Harris corner features detector, and convolution neural network were redesigned using the programmable gates in field-programmable gate array. Based on the field-programmable gate array-based image processing, an image-based visual servo controller was designed to drive a two degree of freedom manipulator to track the target in real time. Finally, experiments on the proposed system were performed to illustrate the effectiveness of the real-time object tracking system.

Mechanistically-Based Field-Scale Models of Uranium Biogeochemistry from Upscaling Pore-Scale Experiments and Models

International Nuclear Information System (INIS)

Tim Scheibe; Alexandre Tartakovsky; Brian Wood; Joe Seymour

2007-01-01

Effective environmental management of DOE sites requires reliable prediction of reactive transport phenomena. A central issue in prediction of subsurface reactive transport is the impact of multiscale physical, chemical, and biological heterogeneity. Heterogeneity manifests itself through incomplete mixing of reactants at scales below those at which concentrations are explicitly defined (i.e., the numerical grid scale). This results in a mismatch between simulated reaction processes (formulated in terms of average concentrations) and actual processes (controlled by local concentrations). At the field scale, this results in apparent scale-dependence of model parameters and inability to utilize laboratory parameters in field models. Accordingly, most field modeling efforts are restricted to empirical estimation of model parameters by fitting to field observations, which renders extrapolation of model predictions beyond fitted conditions unreliable. The objective of this project is to develop a theoretical and computational framework for (1) connecting models of coupled reactive transport from pore-scale processes to field-scale bioremediation through a hierarchy of models that maintain crucial information from the smaller scales at the larger scales; and (2) quantifying the uncertainty that is introduced by both the upscaling process and uncertainty in physical parameters. One of the challenges of addressing scale-dependent effects of coupled processes in heterogeneous porous media is the problem-specificity of solutions. Much effort has been aimed at developing generalized scaling laws or theories, but these require restrictive assumptions that render them ineffective in many real problems. We propose instead an approach that applies physical and numerical experiments at small scales (specifically the pore scale) to a selected model system in order to identify the scaling approach appropriate to that type of problem. Although the results of such studies will

Mechanistically-Based Field-Scale Models of Uranium Biogeochemistry from Upscaling Pore-Scale Experiments and Models

Energy Technology Data Exchange (ETDEWEB)

Tim Scheibe; Alexandre Tartakovsky; Brian Wood; Joe Seymour

2007-04-19

Effective environmental management of DOE sites requires reliable prediction of reactive transport phenomena. A central issue in prediction of subsurface reactive transport is the impact of multiscale physical, chemical, and biological heterogeneity. Heterogeneity manifests itself through incomplete mixing of reactants at scales below those at which concentrations are explicitly defined (i.e., the numerical grid scale). This results in a mismatch between simulated reaction processes (formulated in terms of average concentrations) and actual processes (controlled by local concentrations). At the field scale, this results in apparent scale-dependence of model parameters and inability to utilize laboratory parameters in field models. Accordingly, most field modeling efforts are restricted to empirical estimation of model parameters by fitting to field observations, which renders extrapolation of model predictions beyond fitted conditions unreliable. The objective of this project is to develop a theoretical and computational framework for (1) connecting models of coupled reactive transport from pore-scale processes to field-scale bioremediation through a hierarchy of models that maintain crucial information from the smaller scales at the larger scales; and (2) quantifying the uncertainty that is introduced by both the upscaling process and uncertainty in physical parameters. One of the challenges of addressing scale-dependent effects of coupled processes in heterogeneous porous media is the problem-specificity of solutions. Much effort has been aimed at developing generalized scaling laws or theories, but these require restrictive assumptions that render them ineffective in many real problems. We propose instead an approach that applies physical and numerical experiments at small scales (specifically the pore scale) to a selected model system in order to identify the scaling approach appropriate to that type of problem. Although the results of such studies will

Do entheogen-induced mystical experiences boost the immune system? Psychedelics, peak experiences, and wellness.

Science.gov (United States)

Roberts, T B

1999-01-01

Daily events that boost the immune system (as indicated by levels of salivary immunoglobulin A), some instances of spontaneous remission, and mystical experiences seem to share a similar cluster of thoughts, feelings, moods, perceptions, and behaviors. Entheogens--psychedelic drugs used in a religious context--can also produce mystical experiences (peak experiences, states of unitive consciousness, intense primary religious experiences) with the same cluster of effects. When this happens, is it also possible that such entheogen-induced mystical experiences strengthen the immune system? Might spontaneous remissions occur more frequently under such conditions? This article advances the so called "Emxis hypothesis"--that entheogen-induced mystical experiences influence the immune system.

Comparative study of poloidal field systems for the torus II experiment

International Nuclear Information System (INIS)

Farvaque, L.; Ghazal, S.; Leloup, C.; Pariente, M.; CEA Centre d'Etudes Nucleaires de Fontenay-aux-Roses, 92

1976-11-01

Three types of transformer for the TORUS II experiment are compared: a saturated iron core transformer with an entire magnetic circuit, an air core transformer and a saturated iron core transformer restricted to the central limb [fr

Interface for Barge-in Free Spoken Dialogue System Based on Sound Field Reproduction and Microphone Array

Directory of Open Access Journals (Sweden)

Hinamoto Yoichi

2007-01-01

Full Text Available A barge-in free spoken dialogue interface using sound field control and microphone array is proposed. In the conventional spoken dialogue system using an acoustic echo canceller, it is indispensable to estimate a room transfer function, especially when the transfer function is changed by various interferences. However, the estimation is difficult when the user and the system speak simultaneously. To resolve the problem, we propose a sound field control technique to prevent the response sound from being observed. Combined with a microphone array, the proposed method can achieve high elimination performance with no adaptive process. The efficacy of the proposed interface is ascertained in the experiments on the basis of sound elimination and speech recognition.

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.

fields

Directory of Open Access Journals (Sweden)

Brad J. Arnold

2014-07-01

Full Text Available Surface irrigation, such as flood or furrow, is the predominant form of irrigation in California for agronomic crops. Compared to other irrigation methods, however, it is inefficient in terms of water use; large quantities of water, instead of being used for crop production, are lost to excess deep percolation and tail runoff. In surface-irrigated fields, irrigators commonly cut off the inflow of water when the water advance reaches a familiar or convenient location downfield, but this experience-based strategy has not been very successful in reducing the tail runoff water. Our study compared conventional cutoff practices to a retroactively applied model-based cutoff method in four commercially producing alfalfa fields in Northern California, and evaluated the model using a simple sensor system for practical application in typical alfalfa fields. These field tests illustrated that the model can be used to reduce tail runoff in typical surface-irrigated fields, and using it with a wireless sensor system saves time and labor as well as water.

ASPI experiment: measurements of fields and waves on board the INTERBALL-1 spacecraft

Directory of Open Access Journals (Sweden)

S. Klimov

1997-05-01

Full Text Available The plasma-wave experiment ASPI (analysis of spectra of plasma waves and instabilities on board the INTERBALL spacecraft is a combined wave diagnostics experiment. It performs measurements of the DC and AC magnetic field vector by flux-gate and search-coil sensors, the DC and AC electric field vector by Langmuir double probes and the plasma current by Langmuir split probe. Preliminary data analysis shows the low noise levels of the sensors and the compatibility of new data with the results of previous missions. During several months of in-orbit operation a rich collection of data was acquired, examples of which at the magnetopause and plasma sheet are presented in second part of the paper.

Technetium-99 behavior in the terrestrial environment. Field observations and radiotracer experiments

International Nuclear Information System (INIS)

Tagami, Keiko

2003-01-01

Obtaining data on 99 Tc in the rice paddy field environment is important because Tc is a redox sensitive element. The behavior of Tc is expected to be different under upland field and rice paddy field conditions since the redox conditions in the soil environment differ. However, most of the data on the nuclide behavior in soil were obtained under upland field conditions. To understand the global fallout 99 Tc distributions in soil samples collected in Japan, a simple and rapid separation method was developed in order to determine low-levels of 99 Tc in soil samples by an inductively coupled plasma mass spectrometry. Also, radiotracer experiments using soils under aerobic and anaerobic conditions were carried out to clarify the Tc behavior under paddy field conditions. The results of determination of global fallout 99 Tc in Japanese soils indicated that the radionuclide had been accumulating in rice paddy fields. The mechanisms can be explained by the immobilization of Tc in soil under anaerobic conditions. From the radiotracer experiments, it was clear that under waterlogged conditions, the highly mobile TcO 4 - in soil was readily changed to other immobilized forms, such as TcO 2 , TcS 2 and organically bound forms. To this immobilization, the microbial activity seemed to have an important role in Tc sorption reactions. When the soil, which was once kept in anaerobic conditions, was air-dried again and kept in aerobic conditions, the chemical forms of immobilized Tc did not change remarkably. Interestingly, the similar Tc behavior was observed in a real wet forest near the Chernobyl Reactor. (author)

Partner Preference and Mating System of the Taiwan Field Vole (Microtus kikuchii

Directory of Open Access Journals (Sweden)

Chia-Chien Lee

2014-06-01

Full Text Available The mating system of the Taiwan field vole (Microtus kikuchii has been proposed to be monogamous. In monogamous animals, individuals should exhibit monogamy syndromes, such as little sexual dimorphism and strong pair bonding (a strong social preference for a familiar partner versus a strange one. In this study, we examined the effect of cohabitation on the partner preference. In a reciprocal experiment, all test individuals were cohabited with a heterosexual vole for 24 hr prior to the partner preference trials. We collected the feces of voles before and after the trials, and analyzed the concentration of fecal steroid hormones, including testosterone of males, progesterone and estradiol of females, and corticosterone of all voles. The results showed that the behaviors of focal voles were not influenced by the status (partner or stranger of stimulus vole. There was no significant relationship between steroid hormones and partner preference. Furthermore, the degree of sexual dimorphism in the Taiwan field vole was low, and similar to that of the monogamous prairie vole (M. ochrogaster. In light of this study and other recent findings, we propose that the mating system of the Taiwan field vole is not strictly monogamy, but flexible depending on environmental conditions.

The importance of holdup in contracting: Evidence from a field experiment

NARCIS (Netherlands)

Iyer, R.; Schoar, A.

2008-01-01

This paper explores how the relationship specificity of the investment affects the ex-ante structure of contracts and the ex-post resolution of an ensuing holdup problem. We set up a field experiment in the wholesale market for pens in India where we sent entrepreneurs as auditors to procure large

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

Constraining chameleon field theories using the GammeV afterglow experiments

International Nuclear Information System (INIS)

Upadhye, A.; Steffen, J.H.; Weltman, A.

2009-01-01

The GammeV experiment has constrained the couplings of chameleon scalar fields to matter and photons. Here we present a detailed calculation of the chameleon afterglow rate underlying these constraints. The dependence of GammeV constraints on various assumptions in the calculation is studied. We discuss GammeV-CHASE, a second-generation GammeV experiment, which will improve upon GammeV in several major ways. Using our calculation of the chameleon afterglow rate, we forecast model-independent constraints achievable by GammeV-CHASE. We then apply these constraints to a variety of chameleon models, including quartic chameleons and chameleon dark energy models. The new experiment will be able to probe a large region of parameter space that is beyond the reach of current tests, such as fifth force searches, constraints on the dimming of distant astrophysical objects, and bounds on the variation of the fine structure constant.

Prototype Engineered Barrier System Field Tests

International Nuclear Information System (INIS)

Ramirez, A.L.; Beatty, J.; Buscheck, T.A.

1989-01-01

This paper presents selected preliminary results obtained during the first 54 days of the Prototype Engineered Barrier System Field Tests (PEBSFT) that are being performed in G-Tunnel within the Nevada Test Site. The test described is a precursor to the Engineered Barrier Systems Field Tests (EBSFT). The EBSFT will consist of in situ tests of the geohydrologic and geochemical environment in the near field (within a few meters) of heaters emplaced in welded tuff to simulate the thermal effects of waste packages. The PEBSFTs are being conducted to evaluate the applicability of measurement techniques, numerical models, and procedures for future investigations that will be conducted in the Exploratory Shaft Facilities of the Yucca Mountain Project (YMP). The paper discusses the evolution of hydrothermal behavior during the prototype test, including rock temperatures, changes in rock moisture content, air permeability of fractures, gas pressures, and rock mass gas-phase humidity. 10 refs., 12 figs

Development and Field Testing of the FootFall Planning System for the ATHLETE Robots

Science.gov (United States)

SunSpiral, Vytas; Wheeler, D. W.; Chavez-Clementa, Daniel; Mittman, David

2011-01-01

The FootFall Planning System is a ground-based planning and decision support system designed to facilitate the control of walking activities for the ATHLETE (All-Terrain Hex-Limbed Extra-Terrestrial Explorer) family of robots. ATHLETE was developed at NASA's Jet Propulsion Laboratory (JPL) and is a large six-legged robot designed to serve multiple roles during manned and unmanned missions to the Moon; its roles include transportation, construction and exploration. Over the four years from 2006 through 2010 the FootFall Planning System was developed and adapted to two generations of the ATHLETE robots and tested at two analog field sites (the Human Robotic Systems Project's Integrated Field Test at Moses Lake, Washington, June 2008, and the Desert Research and Technology Studies (D-RATS), held at Black Point Lava Flow in Arizona, September 2010). Having 42 degrees of kinematic freedom, standing to a maximum height of just over 4 meters, and having a payload capacity of 450 kg in Earth gravity, the current version of the ATHLETE robot is a uniquely complex system. A central challenge to this work was the compliance of the high-DOF (Degree Of Freedom) robot, especially the compliance of the wheels, which affected many aspects of statically-stable walking. This paper will review the history of the development of the FootFall system, sharing design decisions, field test experiences, and the lessons learned concerning compliance and self-awareness.

Real-time feedback for spatiotemporal field stabilization in MR systems.

Science.gov (United States)

Duerst, Yolanda; Wilm, Bertram J; Dietrich, Benjamin E; Vannesjo, S Johanna; Barmet, Christoph; Schmid, Thomas; Brunner, David O; Pruessmann, Klaas P

2015-02-01

MR imaging and spectroscopy require a highly stable, uniform background field. The field stability is typically limited by hardware imperfections, external perturbations, or field fluctuations of physiological origin. The purpose of the present work is to address these issues by introducing spatiotemporal field stabilization based on real-time sensing and feedback control. An array of NMR field probes is used to sense the field evolution in a whole-body MR system concurrently with regular system operation. The field observations serve as inputs to a proportional-integral controller that governs correction currents in gradient and higher-order shim coils such as to keep the field stable in a volume of interest. The feedback system was successfully set up, currently reaching a minimum latency of 20 ms. Its utility is first demonstrated by countering thermal field drift during an EPI protocol. It is then used to address respiratory field fluctuations in a T2 *-weighted brain exam, resulting in substantially improved image quality. Feedback field control is an effective means of eliminating dynamic field distortions in MR systems. Third-order spatial control at an update time of 100 ms has proven sufficient to largely eliminate thermal and breathing effects in brain imaging at 7 Tesla. © 2014 Wiley Periodicals, Inc.

A mean field theory of coded CDMA systems

International Nuclear Information System (INIS)

Yano, Toru; Tanaka, Toshiyuki; Saad, David

2008-01-01

We present a mean field theory of code-division multiple-access (CDMA) systems with error-control coding. On the basis of the relation between the free energy and mutual information, we obtain an analytical expression of the maximum spectral efficiency of the coded CDMA system, from which a mean-field description of the coded CDMA system is provided in terms of a bank of scalar Gaussian channels whose variances in general vary at different code symbol positions. Regular low-density parity-check (LDPC)-coded CDMA systems are also discussed as an example of the coded CDMA systems

A mean field theory of coded CDMA systems

Energy Technology Data Exchange (ETDEWEB)

Yano, Toru [Graduate School of Science and Technology, Keio University, Hiyoshi, Kohoku-ku, Yokohama-shi, Kanagawa 223-8522 (Japan); Tanaka, Toshiyuki [Graduate School of Informatics, Kyoto University, Yoshida Hon-machi, Sakyo-ku, Kyoto-shi, Kyoto 606-8501 (Japan); Saad, David [Neural Computing Research Group, Aston University, Birmingham B4 7ET (United Kingdom)], E-mail: yano@thx.appi.keio.ac.jp

2008-08-15

We present a mean field theory of code-division multiple-access (CDMA) systems with error-control coding. On the basis of the relation between the free energy and mutual information, we obtain an analytical expression of the maximum spectral efficiency of the coded CDMA system, from which a mean-field description of the coded CDMA system is provided in terms of a bank of scalar Gaussian channels whose variances in general vary at different code symbol positions. Regular low-density parity-check (LDPC)-coded CDMA systems are also discussed as an example of the coded CDMA systems.

The ITER poloidal field system

Energy Technology Data Exchange (ETDEWEB)

Wesley, J [General Atomics, San Diego, CA (USA); Beljakov, V; Kavin, A; Korshakov, V; Kostenko, A; Roshal, A; Zakharov, L [Kurchatov Inst. of Atomic Energy, Moscow (USSR); Bulmer, R; Kaiser, T; Miller, J R; Pearlstein, L D [Lawrence Livermore National Lab., CA (USA); Hogan, J [Oak Ridge National Lab., TN (USA); Kurihara, K; Shimomura, Y; Sugihara, M; Yoshino, R [Japan Atomic Energy Resea

1990-12-15

The ITER poloidal field (PF) system uses superconducting coils to provide the plasma equilibrium fields, slow equilibrium control and plasma flux linkage (V-s) needed for the ITER Operations and Research Program. Double-null (DN) divertor plasmas and operation scenarios for 22 MA Physics (high-Q/ignition) and 15 MA Technology (high-fluence testing) phases are provided. For 22 MA plasmas, total PF flux swing is 333 V-s. This provides inductive current drive (CD) for start-up with 66 V-s of resistive loss and 440-s (330-s minimum) sustained burn. The PF system also allows plasma start-up and shutdown scenarios, and can maintain the plasma configuration during burn over a range of current and pressure profiles. Other capabilities include increased plasma current (25 MA with inductive CD; 28 MA with non-inductive CD assist), divertor separatrix sweeping, and semi-DN and single-null plasmas.

The magnetic field experiment onboard Equator-S and its scientific possibilities

Directory of Open Access Journals (Sweden)

K.-H. Fornacon

1999-12-01

Full Text Available The special feature of the ringcore fluxgate magnetometer on Equator-S is the high time and field resolution. The scientific aim of the experiment is the investigation of waves in the 10–100 picotesla range with a time resolution up to 64 Hz. The instrument characteristics and the influence of the spacecraft on the magnetic field measurement will be discussed. The work shows that the applied pre- and inflight calibration techniques are sufficient to suppress spacecraft interferences. The offset in spin axis direction was determined for the first time with an independent field measurement by the Equator-S Electron Drift Instrument. The data presented gives an impression of the accuracy of the measurement.Key words. Magnetospheric physics (instruments and techniques · Space plasma physics (instruments and techniques

The magnetic field experiment onboard Equator-S and its scientific possibilities

Directory of Open Access Journals (Sweden)

K.-H. Fornacon

Full Text Available The special feature of the ringcore fluxgate magnetometer on Equator-S is the high time and field resolution. The scientific aim of the experiment is the investigation of waves in the 10–100 picotesla range with a time resolution up to 64 Hz. The instrument characteristics and the influence of the spacecraft on the magnetic field measurement will be discussed. The work shows that the applied pre- and inflight calibration techniques are sufficient to suppress spacecraft interferences. The offset in spin axis direction was determined for the first time with an independent field measurement by the Equator-S Electron Drift Instrument. The data presented gives an impression of the accuracy of the measurement.

Key words. Magnetospheric physics (instruments and techniques · Space plasma physics (instruments and techniques

Nanojets, Electrospray, and Ion Field Evaporation: Molecular Dynamics Simulations and Laboratory Experiments

National Research Council Canada - National Science Library

Luedtke, W. D; Landman, Uzi; Chiu, Y. H; Levandier, D. J; Dressler, R. A; Sok, S; Gordon, M. S

2008-01-01

... experiment and using molecular dynamics (MD) simulations. The electrospray source is operated in a Taylor cone-jet mode, with the nanojet that forms being characterized by high surface-normal electric field strengths in the vicinity of I V/nm...

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

Impact system for ultrafast synchrotron experiments

International Nuclear Information System (INIS)

Jensen, B. J.; Owens, C. T.; Ramos, K. J.; Yeager, J. D.; Saavedra, R. A.; Luo, S. N.; Hooks, D. E.; Iverson, A. J.; Fezzaa, K.

2013-01-01

The impact system for ultrafast synchrotron experiments, or IMPULSE, is a 12.6-mm bore light-gas gun (<1 km/s projectile velocity) designed specifically for performing dynamic compression experiments using the advanced imaging and X-ray diffraction methods available at synchrotron sources. The gun system, capable of reaching projectile velocities up to 1 km/s, was designed to be portable for quick insertion/removal in the experimental hutch at Sector 32 ID-B of the Advanced Photon Source (Argonne, IL) while allowing the target chamber to rotate for sample alignment with the beam. A key challenge in using the gun system to acquire dynamic data on the nanosecond time scale was synchronization (or bracketing) of the impact event with the incident X-ray pulses (80 ps width). A description of the basic gun system used in previous work is provided along with details of an improved launch initiation system designed to significantly reduce the total system time from launch initiation to impact. Experiments were performed to directly measure the gun system time and to determine the gun performance curve for projectile velocities ranging from 0.3 to 0.9 km/s. All results show an average system time of 21.6 ± 4.5 ms, making it possible to better synchronize the gun system and detectors to the X-ray beam.

Review of possible experiments in the eutectic growth and thermodiffusion fields

International Nuclear Information System (INIS)

Malmejac, Yves.

1976-01-01

The results now available from the SKYLAB and ASTP programmes give a clearer indication of the lines of the research to pursue in the years to come. The criteria necessary for the choice of experiments are analysed in the fields of eutectic solidification and diffusion along a temperature gradient in liquid alloys [fr

The Preservice Teachers Are Watching: Framing and Reframing the Field Experience

Science.gov (United States)

Scherff, Lisa; Singer, Nancy Robb

2012-01-01

In this article we employ Sizers' (1999) school- and classroom-based lenses for observation and apply them to the events and interactions that teacher education students see during school-based field experiences. Our data include online reflections and discussions among 33 students enrolled in a teacher education program at a large, public…

Random walks, random fields, and disordered systems

CERN Document Server

Černý, Jiří; Kotecký, Roman

2015-01-01

Focusing on the mathematics that lies at the intersection of probability theory, statistical physics, combinatorics and computer science, this volume collects together lecture notes on recent developments in the area. The common ground of these subjects is perhaps best described by the three terms in the title: Random Walks, Random Fields and Disordered Systems. The specific topics covered include a study of Branching Brownian Motion from the perspective of disordered (spin-glass) systems, a detailed analysis of weakly self-avoiding random walks in four spatial dimensions via methods of field theory and the renormalization group, a study of phase transitions in disordered discrete structures using a rigorous version of the cavity method, a survey of recent work on interacting polymers in the ballisticity regime and, finally, a treatise on two-dimensional loop-soup models and their connection to conformally invariant systems and the Gaussian Free Field. The notes are aimed at early graduate students with a mod...

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.

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

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

Field experiments for student learning – what I learnt in my first weeks in Sweden two decades ago

Science.gov (United States)

Seibert, Jan

2015-04-01

Field experiments can be extremely valuable for obtaining a good understanding of hydrological processes. In this poster I revisit a field course held by Allan Rodhe when I came to Sweden two decades ago, and ask myself, with a long-term perspective, what I learnt during this course. Some of the experiments are described in more detail such as the estimation of hydraulic conductivities based on groundwater salt dilution and an experiment to demonstrate the difference between flood-wave velocity and water particle velocity. Furthermore, some general thoughts on challenges to generate a good learning environment in the field are given based on my personal experiences as a student, an assistant and a teacher.

A Neutron Radiography System for Field Use

Science.gov (United States)

1989-06-01

provoked a major renewal of interest in neutron radiography because it promises to bring neutron radiography to the workplace , a convenience provided...II I~F I C II i IiH i ii MTL TR 89-52 I-AD A NEUTRON RADIOGRAPHY SYSTEM N FOR FIELD USE e~m JOHN J. ANTAL and ALFRED S. MAROTTA, and LOUIS J. FARESE...COVERED A NEUTRON RADIOGRAPHY SYSTEM FOR FIELD USE Final Report 6. PERFORMING OR1. REPORT NUMBER 7. AUTHOR(s) S. CONTRACT OR GRANT NUMBER(s) John J

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

Spatial correlations and probability density function of the phase difference in a developed speckle-field: numerical and natural experiments

International Nuclear Information System (INIS)

Mysina, N Yu; Maksimova, L A; Ryabukho, V P; Gorbatenko, B B

2015-01-01

Investigated are statistical properties of the phase difference of oscillations in speckle-fields at two points in the far-field diffraction region, with different shapes of the scatterer aperture. Statistical and spatial nonuniformity of the probability density function of the field phase difference is established. Numerical experiments show that, for the speckle-fields with an oscillating alternating-sign transverse correlation function, a significant nonuniformity of the probability density function of the phase difference in the correlation region of the field complex amplitude, with the most probable values 0 and p, is observed. A natural statistical interference experiment using Young diagrams has confirmed the results of numerical experiments. (laser applications and other topics in quantum electronics)

A new signal restoration method based on deconvolution of the Point Spread Function (PSF) for the Flat-Field Holographic Concave Grating UV spectrometer system

Science.gov (United States)