WorldWideScience

Sample records for field ionization-photoelectron study

  1. Ionization, photoelectron dynamics and elastic scattering in relativistic, ultra-strong field

    Science.gov (United States)

    Luo, Sui

    Ultrastrong laser-matter interaction has direct bearing to next generation technologies including plasma acceleration, laser fusion and attosecond X-ray generation. The commonly known physics in strong field becomes different as one progress to ultrastrong field. The works presented in this dissertation theoretically study the influence of relativistic effect and magnetic component of the laser field on the ionization, photoelectron dynamics and elastic scattering processes. The influence of magnetic component (B laser) of circularly polarized (CP) ultrastrong fields (up to3 x 1022 W/cm2) on atomic bound state dynamics is investigated. The Poincare plots are used to find the changes in trajectory energies are on the order of a few percent for intensities up to1 x 1022 W/cm2. It is found that at intensities where ionization approaches 50% for the bound state, the small changes from Blaser of the circular polarized light can actually result in a several-fold decrease in ionization probability. The force on the bound electron exerted by the Lorentz force from B laser is perpendicular to the rotating plane of the circular polarized light, and this nature makes those trajectories which are aligned away from the minimum in the potential barrier stabilized against tunneling ionization. Our results provide a classical understanding for ionization in ultrastrong fields and indicate that relativistic effects in ultrastrong field ionization may most easily be seen with CP fields. The photoelectron energy spectra from elastic rescattering in ultrastrong laser fields (up to 2x1019 W/cm2) is studied by using a relativistic adaption of a semi-classical three-step recollision model. The Hartree-Fock scattering potentials are used in calculating the elastic rescattering for both hydrogenlike and noble gas species. It is found that there is a reduction in elastic rescattering for intensities beyond 6 x 1016 W/cm2 when the laser Lorentz deflection of the photoelectron exceeds its

  2. Resonance enhanced multiphoton ionization photoelectron spectroscopy and pulsed field ionization via the F 1D2(v'=0) and f 3D2(v'=0) Rydberg states of HCl

    NARCIS (Netherlands)

    Buma, W.J.; de Beer, E.; de Lange, C.A.

    1993-01-01

    In this paper, we report the first rotationally resolved one- and two-color resonance enhanced multiphoton ionization photoelectron spectroscopy (REMPI-PES) study of the HCl molecule. The agreement between our experimental branching ratios and theoretical investigations is excellent. We also report

  3. Microbial field pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Coates, J.D.; Chisholm, J.L.

    1993-05-01

    A multi-well microbially enhanced oil recovery field pilot has been performed in the Southeast Vassar Vertz Sand Unit in Payne County, Oklahoma. The primary emphasis of the experiment was preferential plugging of high permeability zones for the purpose of improving waterflood sweep efficiency. Studies were performed to determine reservoir chemistry, ecology, and indigenous bacteria populations. Growth experiments were used to select a nutrient system compatible with the reservoir that encouraged growth of a group of indigenous nitrate-using bacteria and inhibit growth of sulfate-reducing bacteria. A specific field pilot area behind an active line drive waterflood was selected. Surface facilities were designed and installed. Injection protocols of bulk nutrient materials were prepared to facilitate uniform distribution of nutrients within the pilot area. By the end of December, 1991, 82.5 tons (75.0 tonnes) of nutrients had been injected in the field. A tracer test identified significant heterogeneity in the SEVVSU and made it necessary to monitor additional production wells in the field. The tracer tests and changes in production behavior indicate the additional production wells monitored during the field trial were also affected. Eighty two and one half barrels (13.1 m[sup 3]) of tertiary oil have been recovered. Microbial activity has increased CO[sub 2] content as indicated by increased alkalinity. A temporary rise in sulfide concentration was experienced. These indicate an active microbial community was generated in the field by the nutrient injection. Pilot area interwell pressure interference test results showed that significant permeability reduction occurred. The interwell permeabilities in the pilot area between the injector and the three pilot production wells were made more uniform which indicates a successful preferential plugging enhanced oil recovery project.

  4. Microbial Field Pilot Study

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Chisholm, J.L.

    1990-11-01

    This report covers progress made during the first year of the Microbial Field Pilot Study project. Information on reservoir ecology and characterization, facility and treatment design, core experiments, bacterial mobility, and mathematical modeling are addressed. To facilitate an understanding of the ecology of the target reservoir analyses of the fluids which support bacteriological growth and the microbiology of the reservoir were performed. A preliminary design of facilities for the operation of the field pilot test was prepared. In addition, procedures for facilities installation and for injection treatments are described. The Southeast Vassar Vertz Sand Unit (SEVVSU), the site of the proposed field pilot study, is described physically, historically, and geologically. The fields current status is presented and the ongoing reservoir simulation is discussed. Core flood experiments conducted during the last year were used to help define possible mechanisms involved in microbial enhanced oil recovery. Two possible mechanisms, relative permeability effects and changes in the capillary number, are discussed and related to four Berea core experiments' results. The experiments were conducted at reservoir temperature using SEVVSU oil, brine, and bacteria. The movement and activity of bacteria in porous media were investigated by monitoring the growth of bacteria in sandpack cores under no flow conditions. The rate of bacteria advancement through the cores was determined. A mathematical model of the MEOR process has been developed. The model is a three phase, seven species, one dimensional model. Finite difference methods are used for solution. Advection terms in balance equations are represented with a third- order upwind differencing scheme to reduce numerical dispersion and oscillations. The model is applied to a batch fermentation example. 52 refs., 26 figs., 21 tabs.

  5. Microbial field pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Chisholm, J.L.

    1992-03-01

    The objective of this project is to perform a microbial enhanced oil recovery field pilot in the Southeast Vassar Vertz Sand Unit (SEVVSU) in Payne County, Oklahoma. Indigenous, anaerobic, nitrate reducing bacteria will be stimulated to selectively plug flow paths which have been referentially swept by a prior waterflood. This will force future flood water to invade bypassed regions of the reservoir and increase sweep efficiency. This report covers progress made during the second year, January 1, 1990 to December 31, 1990, of the Microbial Field Pilot Study project. Information on reservoir ecology, surface facilities design, operation of the unit, core experiments, modeling of microbial processes, and reservoir characterization and simulation are presented in the report. To better understand the ecology of the target reservoir, additional analyses of the fluids which support bacteriological growth and the microbiology of the reservoir were performed. The results of the produced and injected water analysis show increasing sulfide concentrations with respect to time. In March of 1990 Mesa Limited Partnership sold their interest in the SEVVSU to Sullivan and Company. In April, Sullivan and Company assumed operation of the field. The facilities for the field operation of the pilot were refined and implementation was begun. Core flood experiments conducted during the last year were used to help define possible mechanisms involved in microbial enhanced oil recovery. The experiments were performed at SEVVSU temperature using fluids and inoculum from the unit. The model described in last year's report was further validated using results from a core flood experiment. The model was able to simulate the results of one of the core flood experiments with good quality.

  6. Microbial field pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Chisholm, J.L.

    1992-03-01

    The objective of this project is to perform a microbial enhanced oil recovery field pilot in the Southeast Vassar Vertz Sand Unit (SEVVSU) in Payne County, Oklahoma. Indigenous, anaerobic, nitrate reducing bacteria will be stimulated to selectively plug flow paths which have been referentially swept by a prior waterflood. This will force future flood water to invade bypassed regions of the reservoir and increase sweep efficiency. This report covers progress made during the second year, January 1, 1990 to December 31, 1990, of the Microbial Field Pilot Study project. Information on reservoir ecology, surface facilities design, operation of the unit, core experiments, modeling of microbial processes, and reservoir characterization and simulation are presented in the report. To better understand the ecology of the target reservoir, additional analyses of the fluids which support bacteriological growth and the microbiology of the reservoir were performed. The results of the produced and injected water analysis show increasing sulfide concentrations with respect to time. In March of 1990 Mesa Limited Partnership sold their interest in the SEVVSU to Sullivan and Company. In April, Sullivan and Company assumed operation of the field. The facilities for the field operation of the pilot were refined and implementation was begun. Core flood experiments conducted during the last year were used to help define possible mechanisms involved in microbial enhanced oil recovery. The experiments were performed at SEVVSU temperature using fluids and inoculum from the unit. The model described in last year`s report was further validated using results from a core flood experiment. The model was able to simulate the results of one of the core flood experiments with good quality.

  7. Electromagnetic Field Penetration Studies

    Science.gov (United States)

    Deshpande, M.D.

    2000-01-01

    A numerical method is presented to determine electromagnetic shielding effectiveness of rectangular enclosure with apertures on its wall used for input and output connections, control panels, visual-access windows, ventilation panels, etc. Expressing EM fields in terms of cavity Green's function inside the enclosure and the free space Green's function outside the enclosure, integral equations with aperture tangential electric fields as unknown variables are obtained by enforcing the continuity of tangential electric and magnetic fields across the apertures. Using the Method of Moments, the integral equations are solved for unknown aperture fields. From these aperture fields, the EM field inside a rectangular enclosure due to external electromagnetic sources are determined. Numerical results on electric field shielding of a rectangular cavity with a thin rectangular slot obtained using the present method are compared with the results obtained using simple transmission line technique for code validation. The present technique is applied to determine field penetration inside a Boeing-757 by approximating its passenger cabin as a rectangular cavity filled with a homogeneous medium and its passenger windows by rectangular apertures. Preliminary results for, two windows, one on each side of fuselage were considered. Numerical results for Boeing-757 at frequencies 26 MHz, 171-175 MHz, and 428-432 MHz are presented.

  8. Baja California: Field Study

    Science.gov (United States)

    Frey, John; Stewart, Jack

    1974-01-01

    Describes how to plan and execute an extended field trip which provides first hand observation of biological and cultural systems. Socialization of the participants was achieved through common planning and goal achievement. (BR)

  9. Electric field sensor studies

    International Nuclear Information System (INIS)

    Griffith, R.D.; Parks, S.

    1977-01-01

    Above-ground intrusion sensors are reviewed briefly. Buried wire sensors are next considered; feasibility studies were conducted. A triangular system of an overhead transmitter wire exciting two buried sensor wires was developed and tested. It failed sometimes to detect a man making a broad jump. A differential receiver was developed to solve this problem

  10. [Studies in quantum field theory

    International Nuclear Information System (INIS)

    1990-01-01

    During the period 4/1/89--3/31/90 the theoretical physics group supported by Department of Energy Contract No. AC02-78ER04915.A015 and consisting of Professors Bender and Shrauner, Associate Professor Papanicolaou, Assistant Professor Ogilvie, and Senior Research Associate Visser has made progress in many areas of theoretical and mathematical physics. Professors Bender and Shrauner, Associate Professor Papanicolaou, Assistant Professor Ogilvie, and Research Associate Visser are currently conducting research in many areas of high energy theoretical and mathematical physics. These areas include: strong-coupling approximation; classical solutions of non-Abelian gauge theories; mean-field approximation in quantum field theory; path integral and coherent state representations in quantum field theory; lattice gauge calculations; the nature of perturbation theory in large order; quark condensation in QCD; chiral symmetry breaking; the 1/N expansion in quantum field theory; effective potential and action in quantum field theories, including OCD; studies of the early universe and inflation, and quantum gravity

  11. Studies in quantum field theory

    International Nuclear Information System (INIS)

    Bender, C.M.; Mandula, J.E.; Shrauner, J.E.

    1982-01-01

    Washington University is currently conducting research in many areas of high energy theoretical and mathematical physics. These areas include: strong-coupling approximation; classical solutions of non-Abelian gauge theories; mean-field approximation in quantum field theory; path integral and coherent state representations in quantum field theory; lattice gauge calculations; the nature of perturbation theory in large orders; quark condensation in QCD; chiral symmetry breaking; the l/N expansion in quantum field theory; effective potential and action in quantum field theories, including QCD

  12. BPA radon field monitoring study

    International Nuclear Information System (INIS)

    Thor, P.W.

    1984-01-01

    To learn more about radon in homes, and in particular, to determine the concentrations and ranges of concentrations in typical Pacific Northwest residences, the Bonneville Power Administration (BPA) conducted a Radon Field Monitoring Study during the 1982-83 winter heating season. Approximately 290 Northwest homeowners received up to three small passive radon detectors with instructions for deployment within their homes. After two to three months of exposure the detectors were returned for processing and analysis. Radon concentrations and basic house information were obtained for 270 houses located in just over 100 different locations in the region. Results of the monitoring and statistical analyses completed on the data are presented. Histograms are shown indicating the ranges of concentrations in various spaces within a residence. Correlations between these concentrations and house characteristics and construction styles are also presented

  13. BPA radon field monitoring study

    International Nuclear Information System (INIS)

    Thor, P.W.

    1984-01-01

    To learn more about radon in homes, and in particular, to determine the concentrations and ranges of concentrations in typical Pacific Northwest residences, the Bonneville Power Administration (BPA) conducted a Radon Field Monitoring Study during the 1982-83 winter heating season. Approximately 290 Northwest homeowners received up to three small passive radon detectors with instructions for deployment within their homes. After two to three months of exposure the detectors were returned for processing and analysis. Radon concentrations and basic house information were obtained for 270 houses located in just over 100 different locations in the region. Results of the monitoring and statistical analyses completed on the data will be presented. Histograms will be shown indicating the ranges of concentrations in various spaces within a residence. Correlations between these concentrations and house characteristics and construction styles will also be presented. 11 figures

  14. Study of marine magnetic field

    Digital Repository Service at National Institute of Oceanography (India)

    Bhattacharya, G.C.

    to the present although the frequency of reversals has changed considerably through time. During a reversal, the intensity usually decreases by about an order of magnitude for several thousand years, while the field maintains its direction. The field... (IGRF). The IGRF is basically a weighted average of several candidate spherical harmonic models of the main field and its secular variation for a given epoch adopted by International Association of Geomagnetism and Aeronomy (IAGA). The first IGRF...

  15. Near-field solubility studies

    International Nuclear Information System (INIS)

    Thomason, H.P.; Williams, S.J.

    1992-02-01

    Experimental determinations of the solubilities of americium, plutonium, neptunium, protactinium, thorium, radium, lead, tin, palladium and zirconium are reported. These elements have radioactive isotopes of concern in assessments of radioactive waste disposal. All measurements were made under the highly alkaline conditions typical of the near field of a radioactive waste repository which uses cementitious materials for many of the immobilisation matrices, the backfill and the engineered structures. Low redox potentials, typical of those resulting from the corrosion of iron and steel, were simulated for those elements having more than one accessible oxidation state. The dissolved concentrations of the elements were defined using ultrafiltration. In addition, the corrosion of iron and stainless steel was shown to generate low redox potentials in solution and the solubility of iron(II) at high pH was measured and found to be sufficient for it to act as a redox buffer with respect to neptunium and plutonium. (author)

  16. Rapid Capability Fielding Toolbox Study

    Science.gov (United States)

    2010-03-01

    skipped  or  attenuated, depending on the specific effort) are as follows:   The  process  is  initiated  with  the  identification  and  careful ...O.L., “Modeling Methods and Conceptual Design Principles for Reconfigurable Systems”,  Journal  of Mechanical Design, 139, 101102, October 2008.  15...Motorola  Dennis Roberson is Vice Provost and Executive Director of the Institute of Business and  Interprofessional   Studies, as well as Acting

  17. Numerical Study of Electric Field Enhanced Combustion

    KAUST Repository

    Han, Jie

    2016-12-26

    Electric fields can be used to change and control flame properties, for example changing flame speed, enhancing flame stability, or reducing pollutant emission. The ions generated in flames are believed to play the primary role. Although experiments have been carried out to study electric field enhanced combustion, they are not sufficient to explain how the ions in a flame are affected by an electric field. It is therefore necessary to investigate the problem through numerical simulations. In the present work, the electric structure of stabilized CH4/air premixed flames at atmospheric pressure within a direct current field is studied using numerical simulations. This study consists of three parts. First, the transport equations are derived from the Boltzmann kinetic equation for each individual species. Second, a general method for computing the diffusivity and mobility of ions in a gas mixture is introduced. Third, the mechanisms for neutral and charged species are improved to give better predictions of the concentrations of charged species, based on experimental data. Following from this, comprehensive numerical results are presented, including the concentrations and fluxes of charged species, the distributions of the electric field and electric potential, and the electric current-voltage relation. Two new concepts introduced with the numerical results are the plasma sheath and dead zone in the premixed flame. A reactive plasma sheath and a Boltzmann relation sheath are discovered in the region near the electrodes. The plasma sheath penetrates into the flame gas when a voltage is applied, and penetrating further if the voltage is higher. The zone outside the region of sheath penetration is defined as the dead zone. With the two concepts, analytical solutions for the electric field, electric potential and current-voltage curve are derived. The solutions directly describe the electric structure of a premixed flame subject to a DC field. These analytical solutions

  18. Further studies in aesthetic field theory

    International Nuclear Information System (INIS)

    Muraskin, M.

    1984-01-01

    We study different facets of Aesthetic Field Theory. First, we have found within the complex version of the theory a bounded particle system which has more structure than what we have previously observed. The particle is built from planar 3 maxima--minima confluence regions. The confluence region closes in 3 spatial dimensions, so once again we have a ''topological'' particle. If we characterize bound stats by the number of large magnitude regions in close proximity, then the simplest interpretation of what we are seeing is that of a 3 particle bound system. Secondly, again within the framework of complex Aesthetic Field Theory, but using a more symmetric system of equations, we observe a confluence type topological particle spontaneously arising out of the vacuum (creation effect). The particle again has a loop shape. The extended particles thus far found in 4 dimensional Aesthetic Field Theory have always had problems with the spreading of the particle system as time went on. Thirdly, we found a bounded confluence particle system, which in addition to confinement and non attenuation shows the desirable property of not spreading in time. In this case, we work exclusively with real fields. The particle system has a dipole looking shape. We also studied complex null Aesthetic Field Theory in 8 dimensions having a 4 direct-sum 4 structure. We were not able to find a bound to our particle system here

  19. Video Field Studies with your Cell Phone

    DEFF Research Database (Denmark)

    Buur, Jacob; Fraser, Euan

    2010-01-01

    is monumental, that equipment is difficult to handle etc. This tutorial presents a lightweight entry into video field studies, using cheap devices like cell phones and portable webcams for informal shooting and simple computer handling for editing. E.g. how far can you get with an iPhone or a video capable i...

  20. Common Group Problems: A Field Study.

    Science.gov (United States)

    Weinberg, Sanford B.; And Others

    1981-01-01

    A field study of a naturally functioning group (N=125) was conducted to identify common group problems. Trained observers attended group meetings and described the problems encountered. Difficulties of cohesion, leadership, sub-group formation, and personality conflict were identified. (RC)

  1. "Idols" - A Game for Field Studies.

    Science.gov (United States)

    Connally, James T.

    1980-01-01

    Described is a game for field studies titled "Idols." Idols is a struggle of intellect and reason against instinct and superstition. The game involves two "tribes" which are protecting a superstitious legacy while trying to replace it with other forms of wealth and understanding. (Author/DS)

  2. Microbial field pilot study. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Coates, J.D.; Chisholm, J.L.

    1993-05-01

    A multi-well microbially enhanced oil recovery field pilot has been performed in the Southeast Vassar Vertz Sand Unit in Payne County, Oklahoma. The primary emphasis of the experiment was preferential plugging of high permeability zones for the purpose of improving waterflood sweep efficiency. Studies were performed to determine reservoir chemistry, ecology, and indigenous bacteria populations. Growth experiments were used to select a nutrient system compatible with the reservoir that encouraged growth of a group of indigenous nitrate-using bacteria and inhibit growth of sulfate-reducing bacteria. A specific field pilot area behind an active line drive waterflood was selected. Surface facilities were designed and installed. Injection protocols of bulk nutrient materials were prepared to facilitate uniform distribution of nutrients within the pilot area. By the end of December, 1991, 82.5 tons (75.0 tonnes) of nutrients had been injected in the field. A tracer test identified significant heterogeneity in the SEVVSU and made it necessary to monitor additional production wells in the field. The tracer tests and changes in production behavior indicate the additional production wells monitored during the field trial were also affected. Eighty two and one half barrels (13.1 m{sup 3}) of tertiary oil have been recovered. Microbial activity has increased CO{sub 2} content as indicated by increased alkalinity. A temporary rise in sulfide concentration was experienced. These indicate an active microbial community was generated in the field by the nutrient injection. Pilot area interwell pressure interference test results showed that significant permeability reduction occurred. The interwell permeabilities in the pilot area between the injector and the three pilot production wells were made more uniform which indicates a successful preferential plugging enhanced oil recovery project.

  3. Reversed field pinch reactor study 3

    International Nuclear Information System (INIS)

    Hollis, A.A.; Mitchell, J.T.D.

    1977-12-01

    This report, the third of a series on the Reversed Field Pinch Reactor, describes a preliminary concept of the engineering design and layout of this pulsed toroidal reactor, which uses the stable plasma behaviour first observed in ZETA. The basic parameters of the 600 MW(e) reactor are taken from a companion study by Hancox and Spears. The plasma volume is 1.75m minor radius and 16m major radius surrounded by a 1.8m blanket-shield region - with the blanket divided into 14 removable segments for servicing. The magnetic confinement system consists of 28 toroidal field coils situated just outside the blanket and inside the poloidal and vertical field coils and all coils have normal copper conductors. The requirement to incorporate a conducting shell at the front of the blanket to provide a short-time plasma stability has a marked effect on the design. It sets the size of the blanket segment and the scale of the servicing operations, limits the breeding gain and complicates the blanket cooling and its integration with the heat engine. An extensive study will be required to confirm the overall reactor potential of the concept. (author)

  4. Field testing plan for unsaturated zone monitoring and field studies

    International Nuclear Information System (INIS)

    Young, M.H.; Wierenga, P.J.; Warrick, A.W.

    1996-10-01

    The University of Arizona, in cooperation with the Bureau of Economic Geology at The University of Texas at Austin, and Stephens and Associates in Albuquerque, New Mexico has developed a field testing plan for evaluating subsurface monitoring systems. The U.S. Nuclear Regulatory Commission has requested development of these testing plans for low-level radioactive waste disposal sites (LLW) and for monitoring at decommissioned facilities designated under the open-quotes Site Decommissioning Management Planclose quotes (SDMP). The tests are conducted on a 50 m by 50 m plot on the University of Arizona's Maricopa Agricultural Center. Within the 50 m by 50 m plot one finds: (1) an instrumented buried trench, (2) monitoring islands similar to those proposed for the Ward Valley, California LLW Facility, (3) deep borehole monitoring sites, (4) gaseous transport monitoring, and (5) locations for testing non-invasive geophysical measurement techniques. The various subplot areas are instrumented with commercially available instruments such as neutron probes, time domain reflectometry probes, tensiometers, psychrometers, heat dissipation sensors, thermocouples, solution samplers, and cross-hole geophysics electrodes. Measurement depths vary from ground surface to 15 m. The data from the controlled flow and transport experiments, conducted over the plot, will be used to develop an integrated approach to long-term monitoring of the vadose zone at waste disposal sites. The data will also be used to test field-scale flow and transport models. This report describes in detail the design of the experiment and the methodology proposed for evaluating the data

  5. Field study plan for alternate barriers

    International Nuclear Information System (INIS)

    Freeman, H.D.; Gee, G.W.; Relyea, J.F.

    1989-05-01

    Pacific Northwest Laboratory (PNL) is providing technical assistance in selecting, designing, evaluating, and demonstrating protective barriers. As part of this technical assistance effort, asphalt, clay, and chemical grout will be evaluated for use as alternate barriers. The purpose of the subsurface layer is to reduce the likelihood that extreme events (i.e., 100-year maximum storms, etc.) will cause significant drainage through the barrier. The tests on alternate barriers will include laboratory and field analysis of the subsurface layer performance. This field test plan outlines the activities required to test and design subsurface moisture barriers. The test plan covers activities completed in FY 1988 and planned through FY 1992 and includes a field-scale test of one or more of the alternate barriers to demonstrate full-scale application techniques and to provide performance data on a larger scale. Tests on asphalt, clay, and chemical grout were initiated in FY 1988 in small (30.5 cm diameter) tube-layer lysimeters. The parameters used for testing the materials were different for each one. The tests had to take into account the differences in material characteristics and response to change in conditions, as well as information provided by previous studies. 33 refs., 8 figs., 1 tab

  6. Vadose Zone Transport Field Study: Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Ward, Andy L.; Conrad, Mark E.; Daily, William D.; Fink, James B.; Freedman, Vicky L.; Gee, Glendon W.; Hoversten, Gary M.; Keller, Jason M.; Majer, Ernest L.; Murray, Christopher J.; White, Mark D.; Yabusaki, Steven B.; Zhang, Z. F.

    2006-07-31

    From FY 2000 through FY 2003, a series of vadose zone transport field experiments were conducted as part of the U.S. Department of Energy’s Groundwater/Vadose Zone Integration Project Science and Technology Project, now known as the Remediation and Closure Science Project, and managed by the Pacific Northwest National Laboratory (PNNL). The series of experiments included two major field campaigns, one at a 299-E24-11 injection test site near PUREX and a second at a clastic dike site off Army Loop Road. The goals of these experiments were to improve our understanding of vadose zone transport processes; to develop data sets to validate and calibrate vadose zone flow and transport models; and to identify advanced monitoring techniques useful for evaluating flow-and-transport mechanisms and delineating contaminant plumes in the vadose zone at the Hanford Site. This report summarizes the key findings from the field studies and demonstrates how data collected from these studies are being used to improve conceptual models and develop numerical models of flow and transport in Hanford’s vadose zone. Results of these tests have led to a better understanding of the vadose zone. Fine-scale geologic heterogeneities, including grain fabric and lamination, were observed to have a strong effect on the large-scale behavior of contaminant plumes, primarily through increased lateral spreading resulting from anisotropy. Conceptual models have been updated to include lateral spreading and numerical models of unsaturated flow and transport have revised accordingly. A new robust model based on the concept of a connectivity tensor was developed to describe saturation-dependent anisotropy in strongly heterogeneous soils and has been incorporated into PNNL’s Subsurface Transport Over Multiple Phases (STOMP) simulator. Application to field-scale transport problems have led to a better understanding plume behavior at a number of sites where lateral spreading may have dominated waste

  7. QUALITY CONTROL AND IMPROVEMENTS MECHANISM OF STUDY FIELD - FOCUSED ON PROFESSIONAL STUDY FIELD

    Directory of Open Access Journals (Sweden)

    VONDRA, Zdeněk

    2017-03-01

    Full Text Available Quality control mechanism that allows long term improvements of a study field or a study program is necessary for good functioning of educational institution or department in actual nature of competitive universities’ environment. This paper focuses on quality control mechanisms in general and more closely on professional study fields. The professional study fields have been settled in Czech higher education by approving the amendment to the Higher Education Act. This brings new need for control and improvement mechanisms based more on connection to industry practice than on academic publications. The aim of this paper is to explain the importance of gathering information from contact with study field’s stakeholders. These information lead to form appropriate improvements implemented on time. In the case study, there are presented examples of gathered findings and how they are being handled. They include the student‘s expectations that underrate theory although it is needed for basic insight to the industry. The students are also motivated to start their own business. What this paper brings is the proposed continuous development mechanism that helped to improve the bachelors study field Multimedia in Economic Practice and also the general recommendations that should help to any other study field.

  8. Studies of the Martian Magnetic Field

    Science.gov (United States)

    Russell, C. T.

    1998-01-01

    This report covers two awards: the first NAGW-2573 was awarded to enable participation in the Mars 94 mission that slipped to become the Mars 96 mission. Upon the unfortunate failure of Mars 96 to achieve its intended trajectory, the second grant was awarded to closeout the Mars 96 activities. Our initial efforts concentrated on assisting our colleagues: W. Riedler, K. Schwingenschuh, K. Gringanz, M. Verigin and Ye. Yeroshenko with advice on the development of the magnetic field portion of the investigation and to help them with test activities. We also worked with them to properly analyze the Phobos magnetic field and plasma data in order to optimize the return from the Mars 94/96 mission. This activity resulted in 18 papers on Mars scientific topics, and two on the instrumentation. One of these latter two papers was the last of the papers written, and speaks to the value of the closeout award. These 20 papers are listed in the attached bibliography. Because we had previously studied Venus and Titan and since it was becoming evident that the magnetic field was very weak, we compared the various properties of the Martian interaction with those of the analogous interactions at Venus and Titan while other papers simply analyzed the properties of the interaction as Phobos 2 observed them. One very interesting observation was the identification of ions picked up in the solar wind, originating in Mars neutral atmosphere. These had been predicted by our earlier observation of cyclotron waves at the proton gyrofrequency in the region upstream from Mars in the solar wind. Of course, the key question we addressed was that of the intrinsic or induced nature of the Martian magnetic field. We found little evidence for the former and much for the latter point of view. We also discussed the instrumentation planned for the Mars balloon and the instrumentation on the orbiter. In all these studies were very rewarding despite the short span of the Phobos data. Although they did not

  9. Field experimentation in isotope-aided studies

    International Nuclear Information System (INIS)

    Zapata, F.

    1990-01-01

    Isotopic-aided studies involve the application of isotopically labelled fertilizer as tracers for the quantitative and precise determination of the fate of specific nutrient elements in the soil/plant system. The planning of isotopic-aided studies requires a different approach from that followed in the design of normal fertilizer trials because of the cost and supply of isotopically labelled materials, the use of highly specialized equipment and the need for skillful trained staff in the use of isotope techniques both in the field/greenhouse and the laboratory. This report is intended to highlight the main points to be considered while applying those techniques in the field or greenhouse. It has been well established that nuclear techniques are a powerful tool in agricultural research. One should take advantage of the use of such techniques if the following criteria are met: The isotope method is the only way to solve a particular question or to obtain a specific piece of information. There are other methods available for such a purpose but the nuclear method provides a direct and quick means to obtain the needed information resulting in higher economic return

  10. Nuclear geophysics for studying oil fields

    International Nuclear Information System (INIS)

    Alekseev, F.A.; Golovatskaya, I.V.; Gulin, Yu.A.; Dvorkin, I.L.; Dyad'kin, I.G.; Srebrodol'skij, D.M.

    1978-01-01

    Considered are the theory of nuclear geophysics and analytical methods to be used in the study of neutron and gamma-quantum fields. The following questions of nuclear geology are discussed: the regularities of radioactive element distributions in oil/gas bearing sedimentary deposits of oils and underground waters; applications of natural gamma-radiation spectrometry in the study of sedimentary processes and etc. Also described are the nuclear geophysics stationary methods (gamma-logging, gamma-gamma-logging, neutron logging) to be followed when developing geological documentation for borehole profiles; the use and efficiency of stationary and impulse techniques in monitoring an oil minig in different geological/technical conditions; the technique to be used for an additional prospecting of layers (carbonate, primarily) in old cased-off holes; the methods to be used in performing a quality inspection of pipe casing cementation and making measurements of their inner diameter and wall thickness. The investigation technique data are provided to examine boreholes with the aid of radioactive isotopes

  11. Development of a Portable Single Photon Ionization-Photoelectron Ionization Time-of-Flight Mass Spectrometer

    Directory of Open Access Journals (Sweden)

    Yunguang Huang

    2015-01-01

    Full Text Available A vacuum ultraviolet lamp based single photon ionization- (SPI- photoelectron ionization (PEI portable reflecting time-of-flight mass spectrometer (TOFMS was designed for online monitoring gas samples. It has a dual mode ionization source: SPI for analyte with ionization energy (IE below 10.6 eV and PEI for IE higher than 10.6 eV. Two kinds of sampling inlets, a capillary inlet and a membrane inlet, are utilized for high concentration and trace volatile organic compounds, respectively. A mass resolution of 1100 at m/z 64 has been obtained with a total size of 40 × 31 × 29 cm, the weight is 27 kg, and the power consumption is only 70 W. A mixture of benzene, toluene, and xylene (BTX, SO2, and discharging products of SF6 were used to test its performance, and the result showed that the limit of quantitation for BTX is as low as 5 ppbv (S/N = 10 : 1 with linear dynamic ranges greater than four orders of magnitude. The portable TOFMS was also evaluated by analyzing volatile organic compounds from wine and decomposition products of SF6 inside of a gas-insulated switchgear.

  12. Development of a Portable Single Photon Ionization-Photoelectron Ionization Time-of-Flight Mass Spectrometer

    Science.gov (United States)

    Huang, Yunguang; Li, Jinxu; Tang, Bin; Zhu, Liping; Hou, Keyong; Li, Haiyang

    2015-01-01

    A vacuum ultraviolet lamp based single photon ionization- (SPI-) photoelectron ionization (PEI) portable reflecting time-of-flight mass spectrometer (TOFMS) was designed for online monitoring gas samples. It has a dual mode ionization source: SPI for analyte with ionization energy (IE) below 10.6 eV and PEI for IE higher than 10.6 eV. Two kinds of sampling inlets, a capillary inlet and a membrane inlet, are utilized for high concentration and trace volatile organic compounds, respectively. A mass resolution of 1100 at m/z 64 has been obtained with a total size of 40 × 31 × 29 cm, the weight is 27 kg, and the power consumption is only 70 W. A mixture of benzene, toluene, and xylene (BTX), SO2, and discharging products of SF6 were used to test its performance, and the result showed that the limit of quantitation for BTX is as low as 5 ppbv (S/N = 10 : 1) with linear dynamic ranges greater than four orders of magnitude. The portable TOFMS was also evaluated by analyzing volatile organic compounds from wine and decomposition products of SF6 inside of a gas-insulated switchgear. PMID:26587023

  13. [Studies in quantum field theory]: Progress report

    International Nuclear Information System (INIS)

    Polmar, S.K.

    1988-01-01

    The theoretical physics group at Washington University has been devoted to the solution of problems in theoretical and mathematical physics. All of the personnel on this task have a similar approach to their research in that they apply sophisticated analytical and numerical techniques to problems primarily in quantum field theory. Specifically, this group has worked on quantum chromodynamics, classical Yang-Mills fields, chiral symmetry breaking condensates, lattice field theory, strong-coupling approximations, perturbation theory in large order, nonlinear waves, 1/N expansions, quantum solitons, phase transitions, nuclear potentials, and early universe calculations

  14. Combustion Safety Simplified Test Protocol Field Study

    Energy Technology Data Exchange (ETDEWEB)

    Brand, L. [Gas Technology Inst., Des Plaines, IL (United States); Cautley, D. [Gas Technology Inst., Des Plaines, IL (United States); Bohac, D. [Gas Technology Inst., Des Plaines, IL (United States); Francisco, P. [Gas Technology Inst., Des Plaines, IL (United States); Shen, L. [Gas Technology Inst., Des Plaines, IL (United States); Gloss, S. [Gas Technology Inst., Des Plaines, IL (United States)

    2015-11-01

    Combustions safety is an important step in the process of upgrading homes for energy efficiency. There are several approaches used by field practitioners, but researchers have indicated that the test procedures in use are complex to implement and provide too many false positives. Field failures often mean that the house is not upgraded until after remediation or not at all, if not include in the program. In this report the PARR and NorthernSTAR DOE Building America Teams provide a simplified test procedure that is easier to implement and should produce fewer false positives. A survey of state weatherization agencies on combustion safety issues, details of a field data collection instrumentation package, summary of data collected over seven months, data analysis and results are included. The project team collected field data on 11 houses in 2015.

  15. 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)

  16. Geomagnetic Observations for Main Field Studies

    DEFF Research Database (Denmark)

    Matzka, Jürgen; Chulliat, A.; Mandea, M.

    2010-01-01

    and the beginning of geomagnetic repeat stations surveys in the 19th century. In the second half of the 20th century, true global coverage with geomagnetic field measurements was accomplished by magnetometer payloads on low-Earth-orbiting satellites. This article describes the procedures and instruments...... for magnetic field measurements on ground and in space and covers geomagnetic observatories, repeat stations, automatic observatories, satellites and historic observations. Special emphasis is laid on the global network of geomagnetic observatories....

  17. Gendered Choices : Fields of study of adolescents in the Netherlands

    OpenAIRE

    van der Vleuten, M.

    2018-01-01

    Choosing a field of study is an important decision in determining future educational trajectories and occupations, and we know that boys and girls make different field of study choices. Girls are underrepresented in gender-stereotypical masculine fields like science and technology, whereas boys are underrepresented in gender-stereotypical feminine fields like education or health-related fields. This dissertation provides insight in the different ways in which adolescents’ social environment a...

  18. Numerical studies of gauge field theories

    International Nuclear Information System (INIS)

    Creutz, M.

    1981-06-01

    Monte Carlo simulation of statistical systems is a well established technique of the condensed matter physicist. In the last few years, particle theorists have rediscovered this method and are having a marvelous time applying it to quantized gauge field theories. The main result has been strong numerical evidence that the standard SU(3) non-Abelian gauge theory of the strong interaction is capable of simultaneously confining quarks into the physical hadrons and exhibiting asymptotic freedom, the phenomenon of quark interactions being small at short distances. In four dimensions, confinement is a non-perturbative phenomenon. Essentially all models of confinement tie widely separated quarks together with strings of gauge field flux. This gives rise to a linear potential at long distances. A Monte Carlo program generates a sequence of field configuration by a series of random changes of the fields. The algorithm is so constructed that ultimately the probability density for finding any given configuration is proportional to the Boltzmann weighting. We bring our lattices into thermal equilibrium with a heat bath at a temperature specified by the coupling constant. Thus we do computer experiments with four-dimensional crystals stored in a computer memory. As the entire field configuration is stored, we have access to any correlation function desired. These lectures describe the kinds of experiments being done and the implications of these results for strong interaction physics

  19. Reflections on the Field of Educational Management Studies.

    Science.gov (United States)

    Fitz, John

    1999-01-01

    Explores educational management studies as an intellectual field. Draws on Bernstein and Bourieu's theorization of "field" to identify its specialized discourse, field positions and their objective relations, and the location of field occupants (the academic, the practitioner, and the entrepreneur). This configuration shapes educational…

  20. IMOM Field Test Study and Accuracy Verification

    National Research Council Canada - National Science Library

    Levien, Fred

    1998-01-01

    .... It was desired to obtain flight test data for both TAMPS and IMOM in order to compare their ability to accurately predict the effects of Radar Terrain Masking (RTM). It was initially planned to have NPS compare predictive data from both of these systems and then do analysis of how they compared to actual field test data.

  1. Toward a Field of Interfaith Studies

    Science.gov (United States)

    Patel, Eboo

    2013-01-01

    Scholars from a range of fields have long taken an interest in how people who orient around religion differently interact with one another. Indeed, this phenomenon has been the subject of important works in political science ("The Clash of Civilizations" by Samuel Huntington), sociology ("American Grace" by Robert Putnam and…

  2. Combustion Safety Simplified Test Protocol Field Study

    Energy Technology Data Exchange (ETDEWEB)

    Brand, L [Gas Technology Inst., Des Plaines, IL (United States); Cautley, D. [Gas Technology Inst., Des Plaines, IL (United States); Bohac, D. [Gas Technology Inst., Des Plaines, IL (United States); Francisco, P. [Gas Technology Inst., Des Plaines, IL (United States); Shen, L. [Gas Technology Inst., Des Plaines, IL (United States); Gloss, S. [Gas Technology Inst., Des Plaines, IL (United States)

    2015-11-05

    "9Combustions safety is an important step in the process of upgrading homes for energy efficiency. There are several approaches used by field practitioners, but researchers have indicated that the test procedures in use are complex to implement and provide too many false positives. Field failures often mean that the house is not upgraded until after remediation or not at all, if not include in the program. In this report the PARR and NorthernSTAR DOE Building America Teams provide a simplified test procedure that is easier to implement and should produce fewer false positives. A survey of state weatherization agencies on combustion safety issues, details of a field data collection instrumentation package, summary of data collected over seven months, data analysis and results are included. The project provides several key results. State weatherization agencies do not generally track combustion safety failures, the data from those that do suggest that there is little actual evidence that combustion safety failures due to spillage from non-dryer exhaust are common and that only a very small number of homes are subject to the failures. The project team collected field data on 11 houses in 2015. Of these homes, two houses that demonstrated prolonged and excessive spillage were also the only two with venting systems out of compliance with the National Fuel Gas Code. The remaining homes experienced spillage that only occasionally extended beyond the first minute of operation. Combustion zone depressurization, outdoor temperature, and operation of individual fans all provide statistically significant predictors of spillage.

  3. Deformation study of Kamojang geothermal field

    Science.gov (United States)

    Ramdhani, B. D.; Meilano, I.; Sarsito, D. A.

    2017-07-01

    GPS has proven to be an indispensable tool in the effort to understand crust deformation before, during, and after the big earthquake events through data analysis and numerical simulation. The development of GPS technology has been able to prove as a method for the detection of geothermal activity that related to deformation. Furthermore, the correlation of deformation and geothermal activity are related to the analysis of potential hazards in the geothermal field itself. But unfortunately, only few GPS observations established to see the relationship of tectonic and geothermal activity around geothermal energy area in Indonesia. This research will observe the interaction between deformation and geothermal sources around the geothermal field Kamojang using geodetic GPS. There are 4 campaign observed points displacement direction to north-east, and 2 others heading to south-east. The displacement of the observed points may have not able proven cause by deformation of geothermal activity due to duration of observation. Since our research considered as pioneer for such investigation in Indonesia, we expect our methodology and our findings could become a starter for other geothermal field cases in Indonesia.

  4. Gendered Choices : Fields of study of adolescents in the Netherlands

    NARCIS (Netherlands)

    van der Vleuten, M.

    2018-01-01

    Choosing a field of study is an important decision in determining future educational trajectories and occupations, and we know that boys and girls make different field of study choices. Girls are underrepresented in gender-stereotypical masculine fields like science and technology, whereas boys are

  5. Ultrafast Internal Conversion of Aromatic Molecules Studied by Photoelectron Spectroscopy using Sub-20 fs Laser Pulses

    Directory of Open Access Journals (Sweden)

    Toshinori Suzuki

    2014-02-01

    Full Text Available This article describes our recent experimental studies on internal conversion via a conical intersection using photoelectron spectroscopy. Ultrafast S2(ππ*–S1(nπ* internal conversion in pyrazine is observed in real time using sub-20 fs deep ultraviolet pulses (264 and 198 nm. While the photoelectron kinetic energy distribution does not exhibit a clear signature of internal conversion, the photoelectron angular anisotropy unambiguously reveals the sudden change of electron configuration upon internal conversion. An explanation is presented as to why these two observables have different sensitivities to internal conversion. The 198 nm probe photon energy is insufficient for covering the entire Franck-Condon envelopes upon photoionization from S2/S1 to D1/D0. A vacuum ultraviolet free electron laser (SCSS producing 161 nm radiation is employed to solve this problem, while its pulse-to-pulse timing jitter limits the time resolution to about 1 ps. The S2–S1 internal conversion is revisited using the sub-20 fs 159 nm pulse created by filamentation four-wave mixing. Conical intersections between D1(π−1 and D0(n−1 and also between the Rydberg state with a D1 ion core and that with a D0 ion core of pyrazine are studied by He(I photoelectron spectroscopy, pulsed field ionization photoelectron spectroscopy and one-color resonance-enhanced multiphoton ionization spectroscopy. Finally, ultrafast S2(ππ*–S1(ππ* internal conversion in benzene and toluene are compared with pyrazine.

  6. SQM studied in the Field Correlator Method

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, F.I.M., E-mail: flavio@on.br [Observatorio Nacional, MCTI, Rua Gal. Jose Cristino 77, 20921-400 Rio de Janeiro, RJ (Brazil)

    2013-01-02

    By using the recent nonperturbative equation of state of the quark-gluon plasma derived in the formalism of the Field Correlator Method, we investigate the bulk properties of the strange quark matter in {beta}-equilibrium and with charge neutrality at T=p=0. The results show that the stability of strange quark matter with respect to {sup 56}Fe is strongly dependent on the model parameters, namely, the gluon condensate G{sub 2} and the qq{sup Macron} interaction potential V{sub 1}. A remarkable result is that the width of the stability window decreases as V{sub 1} increases, being maximum at V{sub 1}=0 and nearly zero at V{sub 1}=0.5 GeV. For V{sub 1} in the range 0 Less-Than-Or-Slanted-Equal-To V{sub 1} Less-Than-Or-Slanted-Equal-To 0.5 GeV, all values of G{sub 2} are lower than 0.006-0.007 GeV{sup 4} obtained from comparison with lattice data at T{sub c}({mu}=0){approx}170 MeV. Our results do not favor the possibilities for the existence of (either nonnegative or negative) absolutely stable strange quark matter.

  7. Global and site specific multimedia (field) studies

    Energy Technology Data Exchange (ETDEWEB)

    Cutshall, N.H.; Guerin, M.R.

    1987-01-01

    Experience with radioactive fallout, with organic contaminants and with heavy metals has amply demonstrated that cross-media transfers are common and that understanding the transport, cycling, and fate of these contaminants requires a multimedia approach. Nonetheless, pollutants with similar physical and chemical attributes may follow markedly different pathways. The frequency of exceptions to predictions based on simplistic models is also sufficient to show that direct investigation of environmental contamination is essential to confirm validity of models used for conceptualizing a problem or for control. Modeling based on multimedia premises and regulatory controls that encompass multimedia considerations are challenged by a dilemma, however. First, the development of multimedia models or regulatory frameworks represents simplification and generalization. This is true for several reasons: (1) inadequate understanding of physical and environmental factors which control specific cross-media transfer; (2) the absence of specific data on certain multimedia pollutant concentrations; (3) even the most powerful computers do not have sufficient speed and capacity to deal with the known complexities of natural systems. On the other hand, for contaminants such as mercury, it may be necessary to include great detail; the overall distribution in the environment may be less important than the rate of some minor process. With sufficient experience and good judgment of what can be ignored, the simplifications and generalizations can be made. For the present, and for the foreseeable future, however, they absolutely must be accompanied by thorough field validation and monitoring.

  8. Global and site specific multimedia (field) studies

    International Nuclear Information System (INIS)

    Cutshall, N.H.; Guerin, M.R.

    1987-01-01

    Experience with radioactive fallout, with organic contaminants and with heavy metals has amply demonstrated that cross-media transfers are common and that understanding the transport, cycling, and fate of these contaminants requires a multimedia approach. Nonetheless, pollutants with similar physical and chemical attributes may follow markedly different pathways. The frequency of exceptions to predictions based on simplistic models is also sufficient to show that direct investigation of environmental contamination is essential to confirm validity of models used for conceptualizing a problem or for control. Modeling based on multimedia premises and regulatory controls that encompass multimedia considerations are challenged by a dilemma, however. First, the development of multimedia models or regulatory frameworks represents simplification and generalization. This is true for several reasons: (1) inadequate understanding of physical and environmental factors which control specific cross-media transfer; (2) the absence of specific data on certain multimedia pollutant concentrations; (3) even the most powerful computers do not have sufficient speed and capacity to deal with the known complexities of natural systems. On the other hand, for contaminants such as mercury, it may be necessary to include great detail; the overall distribution in the environment may be less important than the rate of some minor process. With sufficient experience and good judgment of what can be ignored, the simplifications and generalizations can be made. For the present, and for the foreseeable future, however, they absolutely must be accompanied by thorough field validation and monitoring

  9. Social Studies: A Field of Dreams?

    Science.gov (United States)

    Larrabee, Larry J.

    1991-01-01

    Discusses the development of social studies from the social upheaval of the industrial revolution to the present. Defines social studies as an integrated, interdisciplinary curriculum for instruction in citizenship education. Lists objectives as gaining necessary knowledge, developing skill in processing information, examining one's own beliefs,…

  10. Plasma Field Studies during Magnetic Disturbances.

    Science.gov (United States)

    1980-06-30

    computationally expensive. In order to study particle accelleration , particle trajectories or guiding center paths must be inte- grated over time. Thus the...should, however, be useful in the study of a classical event and the accompanying particle motions and accellerations . 28 --" .?i

  11. Hitler Studies: A Field of Amateurs

    Directory of Open Access Journals (Sweden)

    Ben Novak

    2009-12-01

    Full Text Available Uno de los más grandes misterios del siglo debe ser el fallo de historiadores profesionales y biógrafos, después de más de medio siglo transcurrido desde los hechos, para mostrarse tanto interés en explicarlo. El hecho de que Hitler continúe siendo un misterio, sin embargo, no es un hecho como otros, para ser registrado como un dato de la historia y dejado a un lado. Un misterio, por definición, es la aparición de algo sorprendente e inesperado que reclama una explicación. Pero, ¿no es uno de los propósitos de la historia (de hecho, la principal función de los historiadores explicar hechos históricos y hacerlos comprensibles? Los historiadores profesionales han rechazado ensuciarse sus manos investigando los muchos misterios de la vida y carrera de Hitler, dedicándose a entrevistar a testigos. Los historiadores no sólo han fallado sino que han sido acusados por colegas de evadir su deber en la transformación de los hechos de la vida y carrera de Hitler en una narración comprensible y coherente.______________________ABSTRACT:One of the greatest mysteries of the century must be the failure of professional historians and biographers, for more than half a century after the event, to show much interest in actually explaining it. The fact that Hitler continues to be a mystery, however, is not a fact like other facts, to be recorded as a datum of history and passed over. A mystery, by definition, is the appearance of something surprising or unexpected that fairly calls out for an explanation. But, is it not one of the purposes of history (indeed, the major function of historians to explain historical events and to make them understandable? Professional historians have consistently refused to get their hands dirty investigating the many mysteries of Hitler’s life and career by going into the field to interview witnesses. Historians have not only failed, but have been charged by fellow historians with "evading", their duty to weave the

  12. NAFTA Guidance Document for Conducting Terrestrial Field Dissipation Studies

    Science.gov (United States)

    Harmonized guidance for TFD studies that demonstrate transformation, transport and fate of pesticides under representative actual use conditions. Field studies substantiate physicochemical, mobility and biotransformation data from laboratory studies.

  13. High field Moessbauer study of dilute Ir-(Fe) alloys

    International Nuclear Information System (INIS)

    Takabatake, Toshiro; Mazaki, Hiromasa; Shinjo, Teruya.

    1981-01-01

    The magnetic behavior of very dilute Fe impurities in Ir has been studied by means of Moessbauer measurement in external fields up to 80 kOe at 4.2 K. The saturation hyperfine field increases in proportion to the external field up to the maximum magnetic field available. This means that for a localized spin fluctuation system IrFe, the effective magnetic moment associated with Fe impurities is induced in proportion to the external field. No anomalous spectrum was observed with a very dilute sample (--10 ppm 57 Co), indicating that the interaction between impurities is responsible for the anomalous spectrum previously observed with a less homogeneous sample. (author)

  14. Study of interacting fields in a canonical formalism in Heisenberg picture of quantum field theory

    International Nuclear Information System (INIS)

    RANAIVOSON, R.T.R.

    2011-01-01

    In this work, we have made a study on the canonical formalism of the quantum field theory. Our contribution has been the development of a study using the Heisenberg picture. We showed that this approach may be useful for the description of quantum dynamics of interacting fields in bounded states. Our approach is to start from the lagrangian density of a classical theory from which one deduce the classical evolution equations of the fields via Euler-Lagrange equation for fields and establish the expression of conserved quantities characterizing the dynamics using the Noether theorem. Passing to the canonical quantization, fields and quantities characterizing the dynamics become quantum operators and evolution equations become operatorial evolution equations in Heisenberg picture. Expressions of quantum observable are also deduced from the expressions of classical conserved quantities. After, we showed that using the properties of fields operators and quantum states vectors, one can deduce from the operatorial evolution equations, the evolution equations for the wave functions of fermions and the evolution equations of expectation values of boson fields. For the illustration, various studies were conducted: the case of electrodynamics, the case of a general gauge theory and the case of the Standard Model. [fr

  15. Magnetic field trimming studies for a separated-sector cyclotron

    International Nuclear Information System (INIS)

    Hudson, E.D.; Martin, J.A.; Mallory, M.L.; McDaniel, F.E.; Irwin, F.

    1975-01-01

    Magnetic field studies were made for a four-sector, K = 330 (E = Kq 2 /A MeV), separated-sector cyclotron using a 1 / 10 scale model of a single sector equipped with 11 trimming coils. Data are presented showing the effects of saturation at high magnetic fields on the field contour and on the trimming coil characteristics. Some implications of these measurements for the design of separated-sector machine magnets are given. (U.S.)

  16. Doing field studies : What is it all about?

    NARCIS (Netherlands)

    Keizer, Kees; Lindenberg, Siegwart; Steg, Linda

    2014-01-01

    Field studies provide much ecological validity but are limited with regard to randomization and control. What can be and what is done about it? Because so few psychologists do field experiments, little is known about it. In our reply to Wicherts and Bakker (in press), we show what goes on behind the

  17. Doing field studies. What is it all about?

    NARCIS (Netherlands)

    Keizer, Kees; Lindenberg, Siegwart; Steg, Linda

    Field studies provide much ecological validity but are limited with regard to randomization and control. What can be and what is done about it? Because so few psychologists do field experiments, little is known about it. In our reply to Wicherts and Bakker (in press), we show what goes on behind the

  18. Culture Studies in the Field of International Business Research

    DEFF Research Database (Denmark)

    Worm, Verner; Li, Xin; Jakobsen, Michael

    Purpose: The purpose of this paper is to describe the status of culture studies within the field of international business research, and to examine how two main paradigms – essentialism and social constructivism – relate to the discourse in this field. We analyze the main points of the two...

  19. Policy Forum: Studying Eyewitness Investigations in the Field

    Science.gov (United States)

    Dawes, Robyn; Jacoby, Larry L.; Kahneman, Daniel; Lempert, Richard; Roediger, Henry L.; Rosenthal, Robert

    2007-01-01

    This article considers methodological issues arising from recent efforts to provide field tests of eyewitness identification procedures. We focus in particular on a field study (Mecklenburg 2006) that examined the “double blind, sequential” technique, and consider the implications of an acknowledged methodological confound in the study. We explain why the confound has severe consequences for assessing the real-world implications of this study. PMID:17610149

  20. Astronaut Neil Armstrong studies rock samples during geological field trip

    Science.gov (United States)

    1969-01-01

    Astronaut Neil Armstrong, commander of the Apollo 11 lunar landing mission, studies rock samples during a geological field trip to the Quitman Mountains area near the Fort Quitman ruins in far west Texas.

  1. Presidential Rhetoric: Definition of a Field of Study.

    Science.gov (United States)

    Windt, Theodore Otto, Jr.

    1984-01-01

    Surveys literature published since 1960, dividing it into four categories of critical analyses. Evaluates current knowledge of presidential rhetoric and suggests directions for future research in this field of study. (PD)

  2. Seismological studies at the Cerro Prieto field, 1978 - 1982

    Science.gov (United States)

    Majer, E. L.; McEvilly, T. V.

    1982-10-01

    Varied seismological studies were conducted to determine the static and dynamic properties of the Cerro Prieto geothermal field. Sought were the relation of wave propagation characteristics and microearthquake activity to such features as production boundaries, recharge zones, heat sources, fluid strata, lithology and structure. Discussed are the results of the studies carried out since 1978 in light of the current knowledge of the Cerro Prieto field. Also included are interpretations of the reflection surveys carried out in the immediate production areas.

  3. A Study of Coaxial Rotor Performance and Flow Field Characteristics

    Science.gov (United States)

    2016-01-22

    1950 (Ref. 8) in the full-scale wind tunnel at NASA Langley Research Center. The coaxial rotor consisted of two 20-in diameter rotors , with two blades...C., “ Wind - tunnel studies of the perfor- mance of multirotor configurations,” NACA TN- 3236, Au- gust 1954. 17Kim, H. W. and Brown, R. E...A Study of Coaxial Rotor Performance and Flow Field Characteristics Natasha L. Barbely Aerospace Engineer NASA Ames Research Center Moffett Field

  4. Fluorescence excitation studies of molecular photoionization in external electric fields

    International Nuclear Information System (INIS)

    Poliakoff, E.D.; Dehmer, J.L.; Parr, A.C.; Leroi, G.E.

    1985-01-01

    Using molecular nitrogen as an example, we show that fluorescence excitation spectroscopy can be used to measure partial photoionization cross sections of free molecules in external electric fields. The production of the N 2 + (B 2 Σ/sub u/ + ) state was studied and the threshold for this process was found to shift linearly with the square root of the applied field. This behavior is compared with the hydrogenic case and with previously studied systems

  5. Visual fields of four batoid fishes: a comparative study.

    Science.gov (United States)

    McComb, D Michelle; Kajiura, Stephen M

    2008-02-01

    The visual fields of elasmobranch fishes are not well characterized even though this is a fundamental element of the visual system. The batoid fishes (skates, rays) form a monophyletic clade within the subclass Elasmobranchii and exhibit a broad range of morphologies and corresponding ecologies. We hypothesized that their visual field characteristics would reflect their diverse morphology and ecology. This was tested by quantifying the monocular, binocular and cyclopean horizontal and vertical visual fields of four batoid species (Raja eglanteria, Urobatis jamaicensis, Dasyatis sabina and Rhinoptera bonasus) that encompassed a range from a basal skate to a more derived ray. The horizontal and vertical visual fields differed significantly among species; however, all species possessed horizontal anterior and dorsal binocular overlaps. Urobatis jamaicensis, a small reef-associated stingray, demonstrated a 360 degrees panoramic visual field in the horizontal plane, and R. bonasus, a schooling benthopelagic ray, a 360 degrees panoramic view in the vertical plane. Large anterior binocular overlaps were measured in D. sabina (72 degrees ) and R. bonasus (46 degrees ) but came at the expense of large posterior blind areas. The anterior binocular overlaps in R. eglanteria (28 degrees ) and U. jamaicensis (34 degrees ) were smaller but were coupled with large monocular fields that provided expansive peripheral views. The most phylogenetically basal species, the clearnose skate (Raja eglanteria), had the most reduced visual field in contrast to the more derived ray species. To our knowledge, this study represents the first comparative assessment of visual fields in basal vertebrates.

  6. Statistical Study of the Magnetic Field Orientation in Solar Filaments

    Science.gov (United States)

    Hanaoka, Yoichiro; Sakurai, Takashi

    2017-12-01

    We have carried out a statistical study of the average orientation of the magnetic field in solar filaments with respect to their axes for more than 400 samples, based on data taken with daily full-Sun, full-Stokes spectropolarimetric observations using the He I 1083.0 nm line. The major part of the samples are the filaments in the quiet areas, but those in the active areas are included as well. The average orientation of the magnetic field in filaments shows a systematic property depending on the hemisphere; the direction of the magnetic field in filaments in the northern (southern) hemisphere mostly deviates clockwise (counterclockwise) from their axes, which run along the magnetic polarity inversion line. The deviation angles of the magnetic field from the axes are concentrated between 10° and 30°. This hemispheric pattern is consistent with that revealed for chirality of filament barbs, filament channels, and for other solar features found to possess chirality. For some filaments, it was confirmed that their magnetic field direction is locally parallel to their structure seen in Hα images. Our results for the first time confirmed this hemispheric pattern with the direct observation of the magnetic field in filaments. Interestingly, the filaments which show the opposite magnetic field deviation to the hemispheric pattern, are in many cases found above the polarity inversion line whose ambient photospheric magnetic field has the polarity alignment being opposite to that of active regions following the Hale–Nicholson law.

  7. Magnetic field effects on humans: epidemiological study design

    Energy Technology Data Exchange (ETDEWEB)

    Budinger, T.F.; Wong, P.; Yen, C.K.

    1978-10-01

    This report presents details of the study design and methods for a retrospective epidemiological study on the health effects, if any, of stationary and alternating magnetic fields produced by man-made devices such as cyclotrons, controlled thermonuclear reactors (CTR), high voltage-high current transmission lines, magnetohydrodynamic devices (MHD), energy storage systems, and isotope separation facilities. The magnetic fields to which the workers can be exposed are as high as 10,000 gauss and the anticipated increase in magnetic fields associated with the environment and transmission lines near these devices is a few times the natural earth magnetic field. Thus the objectives include acquisition of low exposure data which can be used to evaluate any risks to the population incidentally exposed to environmental increases in magnetic fields, as well as an acquisition of high exposure data to be used in determining allowable exposure standards for the technical personnel working at CTR and MHD facilities. From the present status of knowledge on biological effects of magnetic fields, it is not possible to extrapolate or rationally conclude maximum permissible exposure levels for magnetic device workers and the population at large. There are no known previous studies of the effects of long-term exposure to magnetic fields involving large samples and matched controls. Thus this human epidemiological study was commenced in 1977 in parallel with experimental studies on biological and medical effects of magnetic fields being conducted by Dr. T. Tenforde and co-workers at LBL, by investigators at Battelle Northwest, and smaller projects at a number of laboratories around the world. The data base for the exposed population is comprised of approximately 1,000 cyclotron and bubble chamber workers.

  8. Influence of field study on learning and attitudes toward science

    Science.gov (United States)

    Brackney, David L.

    In an effort to improve attitudes toward science and academic achievement among college students who are non-science majors, an informal science educational experience in the form of a natural science field study course was created. The purpose of this study was to investigate the impact of a field study experience on student science attitudes and achievement. Outcomes from the field study groups were compared to students who enrolled in a traditional lecture/lab course. Academic achievement was measured via pre and posttest measures of geologic knowledge. Attitudes toward science were measured with a Science Attitudes Survey that utilized Likert-scale type items in the instrument. To explore student impressions and reactions to participating in the field study experience, interviews were conducted with open-ended questions. Patterns of responses were identified to explore common themes. Field study participants were found to have significantly higher gains from pre to posttest scores compared with the gains made by students who participated in a formal Earth Science course. There was no significant difference found in overall attitudes toward science and technology as measured with this attitudes survey between students who participated in the two formats of courses over the last five years. However, comments shared by participants in the field study through interviews suggest that their attitudes toward science had in fact been affected in positive ways. Other patterns of responses indicate positive impacts made on students on a number of fronts including affective, cognitive, and social interactions. All students interviewed rated the field study experience as valuable educationally or extremely valuable educationally.

  9. Sonic boom startle effects : report of a field study.

    Science.gov (United States)

    1973-07-01

    The study reports the results of a sonic boom field study conducted in Sweden during October 1972. Ten female subjects were tested indoors on each of six days. Two age groups were studied: 20-35 and 50-65 years. Fighter aircraft flying at various hei...

  10. NATO Advanced Study Institute on Atoms in Strong Fields

    CERN Document Server

    Clark, Charles; Nayfeh, Munir

    1990-01-01

    This book collects the lectures given at the NATO Advanced Study Institute on "Atoms in Strong Fields", which took place on the island of Kos, Greece, during the two weeks of October 9-21,1988. The designation "strong field" applies here to an external electromagnetic field that is sufficiently strong to cause highly nonlinear alterations in atomic or molecular struc­ ture and dynamics. The specific topics treated in this volume fall into two general cater­ gories, which are those for which strong field effects can be studied in detail in terrestrial laboratories: the dynamics of excited states in static or quasi-static electric and magnetic fields; and the interaction of atoms and molecules with intense laser radiation. In both areas there exist promising opportunities for research of a fundamental nature. An electric field of even a few volts per centimeter can be very strong on the atom­ ic scale, if it acts upon a weakly bound state. The study of Rydberg states with high reso­ lution laser spectroscop...

  11. ArcGIS studies and field relationships of Paleoproterozoic mafic ...

    Indian Academy of Sciences (India)

    Google Earth Image and cross-cutting field relationships of distinct Paleoproterozoic mafic dykes from south of Devarakonda area in the Eastern .... range of applications (Legg 1994; Rajesh 2004). For the present study, an ArcGIS ... metric ages have been used as such studies could be the best elements to interpret their ...

  12. Educational Investments and Economic Development: A Field Study.

    Science.gov (United States)

    Champaigne, John

    A study examined the relationship between educational investments and economic development in the small community of Canandaigua, New York. A field study approach was used to collect data pertaining to the city's population characteristics, income characteristics, economic conditions, unemployment rates, and housing conditions. These data were…

  13. Monte Carlo study of MLC fields for cobalt therapy machine

    Directory of Open Access Journals (Sweden)

    Komanduri M Ayyangar

    2014-01-01

    Full Text Available An automated Multi-Leaf Collimator (MLC system has been developed as add-on for the cobalt-60 teletherapy machines available in India. The goal of the present computational study is to validate the MLC design using Monte Carlo (MC modeling. The study was based on the Kirloskar-supplied Phoenix model machines that closely match the Atomic Energy of Canada Limited (AECL theratron-80 machine. The MLC is a retrofit attachment to the collimator assembly, with 14 non-divergent leaf pairs of 40 mm thick, 7 mm wide, and 150 mm long tungsten alloy plates with rounded edges and 20 mm tongue and 2 mm groove in each leaf. In the present work, the source and collimator geometry has been investigated in detail to arrive at a model that best represents the measured dosimetric data. The authors have studied in detail the proto-I MLC built for cobalt-60. The MLC field sizes were MC simulated for 2 × 2 cm 2 to 14 × 14 cm 2 square fields as well as irregular fields, and the percent depth dose (PDD and profile data were compared with ROPS† treatment planning system (TPS. In addition, measured profiles using the IMATRIXX system‡ were also compared with the MC simulations. The proto-I MLC can define radiation fields up to 14 × 14 cm΂ within 3 mm accuracy. The maximum measured leakage through the leaf ends in closed condition was 3.4% and interleaf leakage observed was 7.3%. Good agreement between MC results, ROPS and IMATRIXX results has been observed. The investigation also supports the hypothesis that optical and radiation field coincidence exists for the square fields studied with the MLC. Plots of the percent depth dose (PDD data and profile data for clinically significant irregular fields have also been presented. The MC model was also investigated to speed up the calculations to allow calculations of clinically relevant conformal beams.

  14. Whole-Home Dehumidifiers: Field-Monitoring Study

    Energy Technology Data Exchange (ETDEWEB)

    Burke, Tom; Willem, Henry; Ni, Chun Chun; Stratton, Hannah; Whitehead, Camilla Dunham; Johnson, Russell

    2014-09-23

    Lawrence Berkeley National Laboratory (LBNL) initiated a WHD field-metering study to expand current knowledge of and obtain data on WHD operation and energy consumption in real-world applications. The field study collected real-time data on WHD energy consumption, along with information regarding housing characteristics, consumer behavior, and various outdoor conditions expected to affect WHD performance and efficiency. Although the metering study collected similar data regarding air conditioner operation, this report discusses only WHDs. The primary objectives of the LBNL field-metering study are to (1) expand knowledge of the configurations, energy consumption profiles, consumer patterns of use (e.g., relative humidity [RH] settings), and environmental parameters of whole-home dehumidification systems; and (2) develop distributions of hours of dehumidifier operation in four operating modes: off, standby, fan-only, and compressor (also called dehumidification mode). Profiling energy consumption entails documenting the power consumption, duration of power consumption in different modes, condensate generation, and properties of output air of an installed system under field conditions of varying inlet air temperature and RH, as well as system configuration. This profiling provides a more detailed and deeper understanding of WHD operation and its complexities. This report describes LBNL’s whole-home dehumidification field-metering study conducted at four homes in Wisconsin and Florida. The initial phase of the WHD field-metering study was conducted on one home in Madison, Wisconsin, from June to December of 2013. During a second phase, three Florida homes were metered from June to October of 2014. This report presents and examines data from the Wisconsin site and from the three Florida sites.

  15. International Scientific Cooperation in the Field of Spatial Studies

    Directory of Open Access Journals (Sweden)

    Pavel Aleksandrovich Minakir

    2014-06-01

    Full Text Available The paper discusses the existing structure of international cooperation of scientific organizations in the field of regional studies in different parts of the world. The authors define current major organizations that coordinate the work of scientific subdivisions in the field of regional studies in the whole world and also in Europe, North and South America and the Asia-Pacific region. The researchers offer the new term - ‘public-scientific partnership’ (PSP - and discuss PSP mechanisms and its implementation ways that may strengthen regional scientific research in Russia. The authors also debate the idea of creation of the Russian Association of Regional Science

  16. HYDROLOGY-METEOROLOGY FIELD OF STUDY – CHANCES FOR LIFE

    Directory of Open Access Journals (Sweden)

    PANDI G.

    2014-03-01

    Full Text Available Geographical teaching has a long tradition in Cluj-Napoca. There are many fields of study at the Faculty of Geography from Cluj-Napoca, which has separated from a larger faculty in 1994, such is Hydrology – Meteorology. It first appeared in 2006, and already has five generations of students. The enquiry made at eight institutions between 1972 and 2013 shows that students’ penetration inside meteorological and hydrological institutions was a good one. A big part of these students come from the Geography field of study, which has a long tradition, and from the new field – Hydro-Meteorology. It can be observed a pronounced increase of employment since 1999. The biggest chances in obtaining a job in this field appear three years after the graduation. Many specialists finished their Geography studies after obtaining the job. Most of our students work as hydrologist or meteorologist, but also in other jobs, a great number belonging to those working in leadership positions. From this enquiry it can be observed that the field of Hydrology – Meteorology was an appropriate one, succeeding to fulfil its purpose.

  17. Competencies of Track and Field coaches. An Exploratory Study

    Directory of Open Access Journals (Sweden)

    Alexandra Tripolitsioti

    2012-01-01

    Full Text Available The aim of this study was to construct a questionnaire to identify the knowledge and skills needed by track and field coaches in Greece to perform their role. Following standard procedures, an instrument with 42 items was constructed. Three hundred and forty nine Greek track and field coaches, who have been working 15+-2.8 y in the first and second division, aged 45+-4.4 y, participated in the study and rated the items of the questionnaire according to a Likert scale. Exploratory factor analysis revealed five factors comprising 22 competency statements: a field management techniques (7 items, b sport science (5 items, c injury prevention/crisis management (3 items; d biology (3 items; and e field training (4 items. The internal validity revealed a Cronbach’s alpha factor of 0.894 with subscales ranging from 0.657 to 0.886. Results also showed that demonstrating an understanding of specific inherent risks of sport activity and an understanding of psychology were the top rated competencies, while preparing a budget proposal and utilizing effective office procedures to handle registrations, reports, notices, etc., were the lower rated competencies. It is concluded that the questionnaire developed in this study is a reliable and valid instrument to measure the competencies of track and field coaches in Greece.

  18. Field emission study of MWCNT/conducting polymer nanocomposite

    Energy Technology Data Exchange (ETDEWEB)

    Alvi, M.A., E-mail: maalvee@yahoo.co.in [Department of Physics, King Abdulaziz University, Jeddah-21589 (Saudi Arabia); Al-Ghamdi, A.A. [Department of Physics, King Abdulaziz University, Jeddah-21589 (Saudi Arabia); Husain, M. [Department of Physics, Jamia Millia Islamia, New Delhi-110025 (India)

    2014-12-01

    MWCNTs/Polypyrrole nanocomposites were synthesized by solution mixing method. These synthesized nanocomposites were studied carefully by Raman Spectroscopy and Scanning Electron Microscopy measurements. The field emission study of MWCNTs/Polypyrrole nanocomposites were performed in diode arrangement under vacuum of the order of 10{sup −5} Torr. The emission current under exploration depends on applied voltage. The prepared nanocomposites depict low turn-on field at 1.4 V/μm that reaches to a maximum emission current density 0.020 mA/cm{sup 2} at 2.4 V/µm, which is calculated from the graph of current density (J) against the applied electric field (E) and from Fowler–Nordheim (F–N) plot.

  19. Local Magnetic Fields in Ferromagnetics Studied by Positive Muon Precession

    CERN Multimedia

    2002-01-01

    Positive muons are used to study local magnetic fields in different materials. A polarized muon beam is employed with energies of 30-50 MeV, and the muons are stopped in the target being studied. During its lifetime the muon will precess in the magnetic fields present, and after the decay of the muon the emitted positron is detected in plastic scintillators. The time and angle of the detected positron is used to calculate the magnetic field at the position of the muon in the sample. \\\\ \\\\ The detector system consists of plastic scintillators. Most of the measurements are made in an applied magnetic field. A dilution cryostat is used to produce temperatures down to well below $ 1 ^0 $ K. \\\\ \\\\ The present line of experiments concern mainly: \\item a)~~~~Local magnetism in the paramagnetic state of the Lave's phase type REAl$_{2} $ and RENi$_{2} $ systems ~~~where RE is a rare-earth ion. \\item b)~~~~Local magnetic fields and critical behaviour of the magnetism in Gd metal. \\item c)~~~~Investigation of flux exclu...

  20. Faraday Rotation Measure Study of Cluster Magnetic Fields

    Science.gov (United States)

    Frankel, M. M.; Clarke, T. E.

    2001-12-01

    Magnetic fields are thought to play an important role in galaxy cluster evolution. To this end in this study, we looked at polarized radio sources viewed at small impact parameters to the cores of non-cooling flow clusters. By looking at non-cooling flow clusters we hoped to establish what magnetic fields of clusters look like in the absence of the compressed central magnetic fields of the cooling-flow cores. Clarke, Kronberg and Boehringer (2001) examined Faraday rotation measures of radio probes at relatively large impact parameters to the cores of galaxy clusters. The current study is an extension of the Clarke et al. analysis to probe the magnetic fields in the cores of galaxy clusters. We looked at the Faraday rotation of electromagnetic waves from background or imbedded radio galaxies, which were observed with the VLA in A&B arrays. Our results are consistent with previous findings and exhibit a trend towards higher rotation measures and in turn higher magnetic fields at small impact parameters to cluster cores. This research was made possible through funding from the National Science Foundation.

  1. Personality and Field of Study Choice in University

    Science.gov (United States)

    Humburg, Martin

    2017-01-01

    This paper demonstrates that the Big five personality traits (openness to experience, conscientiousness, extraversion, agreeableness, and emotional stability) measured at age 14 can be linked to field of study choice in university at around age 19. While personality matters less than cognitive skills, such as math ability and verbal ability, for…

  2. ArcGIS studies and field relationships of Paleoproterozoic mafic ...

    Indian Academy of Sciences (India)

    Therefore, relative age relationships of distinct mafic dykes have been established for the study area using cross-cutting field relationships and GIS techniques, which shows slightly different picture than other parts of the Eastern Dharwar Craton. It is suggested that NE–SW trending mafic dykes are youngest in age ...

  3. Which Is More Consequential: Fields of Study or Institutional Selectivity?

    Science.gov (United States)

    Ma, Yingyi; Savas, Gokhan

    2014-01-01

    The persisting gender pay gap favoring men among college graduates is a puzzle given women's remarkable success in postsecondary education. This article examines income disparities among recent college graduates by intersecting gender and social class and evaluating the relative importance of fields of study and institutional selectivity.…

  4. Assessing Student Learning in the Major Field of Study

    Science.gov (United States)

    Volkwein, J. Fredericks

    2010-01-01

    Assessing student attainment in the major field of study is increasingly important to employers and accrediting bodies alike. Construction and manufacturing firms do not like engineers who design faulty bridges and airplanes. Marketing firms want to hire students who understand the difference between a niche market and a global market. School…

  5. Field Research Studying Whales in an Undergraduate Animal Behavior Laboratory

    Science.gov (United States)

    MacLaren, R. David; Schulte, Dianna; Kennedy, Jen

    2012-01-01

    This work describes a new field research laboratory in an undergraduate animal behavior course involving the study of whale behavior, ecology and conservation in partnership with a non-profit research organization--the Blue Ocean Society for Marine Conservation (BOS). The project involves two weeks of training and five weekend trips on whale watch…

  6. Noise Studies on Injected-Beam Crossed-Field Devices.

    Science.gov (United States)

    1980-11-01

    numerous experimental and theoretical studies. A large contribution to the understanding was made I by Van Duzer , Whinnery, and co-workers of the...Conference, Amsterdam, Netherlands, pp. 8-31, 1970. 10. T. Van Duzer , J. Whinnery, "Noise in Electron Beams", Crossed-Field Microwave Devices (E. Okress, ed

  7. Are Facilitated Mentoring Programs Beneficial? A Randomized Experimental Field Study

    Science.gov (United States)

    Egan, Toby Marshall; Song, Zhaoli

    2008-01-01

    Results from a pretest-posttest randomized field experiment study with a control group comparing the impact of high- and low-level-facilitated mentoring programs on new employees' performance and perceptions about their jobs and organization were reported in this paper. Results indicated increases in job satisfaction, organizational commitment,…

  8. Astronauts Armstrong and Aldrin study rock samples during field trip

    Science.gov (United States)

    1969-01-01

    Astronaut Neil Armstrong, commander of the Apollo 11 lunar landing mission, and Astronaut Edwin Aldrin, Lunar module pilot for Apollo 11, study rock samples during a geological field trip to the Quitman Mountains area near the Fort Quitman ruins in far west Texas.

  9. The significance of field work in monographic studies

    Science.gov (United States)

    The focus of this paper is to document the clear and obvious advantages of field work for monographic studies. These advantages include: 1) ability to understand published distributions better and greatly expand these data, 2) access to taxonomic data obscured on herbarium sheets (as colors, odors, ...

  10. Enhanced Field Emission Studies on Niobium Surfaces Relevant to High Field Superconducting Radio-Frequency Devices

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Tong [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States)

    2002-09-18

    Enhanced field emission (EFE) presents the main impediment to higher acceleration gradients in superconducting niobium (Nb) radiofrequency cavities for particle accelerators. The strength, number and sources of EFE sites strongly depend on surface preparation and handling. The main objective of this thesis project is to systematically investigate the sources of EFE from Nb, to evaluate the best available surface preparation techniques with respect to resulting field emission, and to establish an optimized process to minimize or eliminate EFE. To achieve these goals, a scanning field emission microscope (SFEM) was designed and built as an extension to an existing commercial scanning electron microscope (SEM). In the SFEM chamber of ultra high vacuum, a sample is moved laterally in a raster pattern under a high voltage anode tip for EFE detection and localization. The sample is then transferred under vacuum to the SEM chamber equipped with an energy-dispersive x-ray spectrometer for individual emitting site characterization. Compared to other systems built for similar purposes, this apparatus has low cost and maintenance, high operational flexibility, considerably bigger scan area, as well as reliable performance. EFE sources from planar Nb have been studied after various surface preparation, including chemical etching and electropolishing, combined with ultrasonic or high-pressure water rinse. Emitters have been identified, analyzed and the preparation process has been examined and improved based on EFE results. As a result, field-emission-free or near field-emission-free surfaces at ~140 MV/m have been consistently achieved with the above techniques. Characterization on the remaining emitters leads to the conclusion that no evidence of intrinsic emitters, i.e., no fundamental electric field limit induced by EFE, has been observed up to ~140 MV/m. Chemically etched and electropolished Nb are compared and no significant difference is observed up to ~140 MV/m. To

  11. Integrated modeling and field study of potential mechanisms forinduced seismicity at The Geysers Goethermal Field, California

    Energy Technology Data Exchange (ETDEWEB)

    Rutqvist, Jonny; Majer, Ernie; Oldenburg, Curt; Peterson, John; Vasco, Don

    2006-06-07

    In this paper, we present progress made in a study aimed atincreasing the understanding of the relative contributions of differentmechanisms that may be causing the seismicity occurring at The Geysersgeothermal field, California. The approach we take is to integrate: (1)coupled reservoir geomechanical numerical modeling, (2) data fromrecently upgraded and expanded NCPA/Calpine/LBNL seismic arrays, and (3)tens of years of archival InSAR data from monthly satellite passes. Wehave conducted a coupled reservoir geomechanical analysis to studypotential mechanisms induced by steam production. Our simulation resultscorroborate co-locations of hypocenter field observations of inducedseismicity and their correlation with steam production as reported in theliterature. Seismic and InSAR data are being collected and processed foruse in constraining the coupled reservoir geomechanicalmodel.

  12. Zero-field-cooled/field-cooled magnetization study of Dendrimer model

    Energy Technology Data Exchange (ETDEWEB)

    Arejdal, M., E-mail: arejdal.achdad@gmail.com [Laboratory of Magnetism and Physics of High Energies, Department of Physics, L.M.P.H.E (URAC-12), Faculty of Sciences, Mohammed V University, Rabat (Morocco); Bahmad, L. [Laboratory of Magnetism and Physics of High Energies, Department of Physics, L.M.P.H.E (URAC-12), Faculty of Sciences, Mohammed V University, Rabat (Morocco); Benyoussef, A. [Hassan II Academy of Science and Technology, Rabat (Morocco)

    2017-01-01

    Being motivated by Dendrimer model with mixed spins σ=3 and S=7/2, we investigated the magnetic nanoparticle system in this study. We analyzed and discussed the ground-state phase diagrams and the stable phases. Then, we elaborated and explained the magnetic properties of the system by using Monte Carlo Simulations (MCS) in the framework of the Ising model. In this way, we determined the blocking temperature, which is deduced through studying the partial-total magnetization and susceptibility as a function of the temperature, and we established the effects of both the exchange coupling interaction and the crystal field on the hysteresis loop.

  13. Understanding the Adoption of Ada: A Field Study Report

    Science.gov (United States)

    1989-08-01

    a name change. The name Ada comes from Augusta Ada Byron, Countess of Lovelace , Charles Babbage’s colleague, and according to some, the first computer...Adoption of Ada : * 1 A Field Study Report A Gordon N. Smith Wesley M. Cohen William E. Hefley Daniel A. Levinthal. August 1989 E DTIC *ie jApproved f or...Puib1I release; -A’Djqtribution Unbmtod 0 (3 134 154 Technical Report 0 SEI-88-TR-28 ESD-TR-88-37 August 1989 Understanding the Adoption of Ada : A Field

  14. Swarm: A constellation to study the Earth's magnetic field

    DEFF Research Database (Denmark)

    Friis-Christensen, Eigil; Luhr, H.; Hulot, G.

    2006-01-01

    The Swarm mission was selected as the 5th mission in ESA's Earth Explorer Programme in 2004. The mission will provide the best ever survey of the geomagnetic field and its temporal evolution that will lead to new insights into the Earth system by improving our understanding of the Earth's interio......'s influence within the Earth system. In addition practical applications in many different areas, such as space weather, radiation hazards, navigation and resource management, will benefit from the Swarm concept....... field measurements, will provide the necessary observations that are required to separate and model the various Sources of the geomagnetic field. This results in it unique "view" inside the Earth from space to study the composition and processes of its interior. It also allows analysing the Sun...

  15. Radial electrical field effects in TJ-II. (Preliminary study)

    International Nuclear Information System (INIS)

    Guasp, J.

    1996-01-01

    The influence of the radial electric field upon the neoclassical transport coefficients of TJ-II helical axis Stellarator has been calculated as well on the microwave heating stage (ECRH) as on the neutral injection one (NBI). The influence of the solutions for the self-consistent ambipolar field on confinement times and temperatures has been studied by means of a zero-dimensional energy balance. The simultaneous presence of two roots, the electronic and the ionic one, is observed for the ECRH phase, while for NBI only the ionic root appears, although with a strong field intensity that could produce a favourable effect on confinement. The interest and need of the extension of these calculations to include radial profile effects by using spatial dependent transport codes in stressed

  16. HVAC systems in a field laboratory for indoor climate study

    DEFF Research Database (Denmark)

    Fang, Lei; Melikov, Arsen Krikor; Olesen, Bjarne W.

    2012-01-01

    convectors. The field lab was designed for experimental research, education and demonstration of ventilation and air-conditioning principals with special focus on studying the impact of different air distribution and heating/cooling methods on human comfort and health. The system can also be used for testing......This paper presents the design of a HVAC system for a field lab. The design integrated mixing ventilation, displacement ventilation, low impulse vertical ventilation, personalized ventilation, natural ventilation, hybrid ventilation, active chilled beams, radiant ceiling and floor, and heat...... under realistic conditions the performance of air processing units (e.g. a special air handling unit, an air cleaning devices, etc.) including their energy consumption and human response. The field lab can accommodate up to 50 occupants and supply 750 L/s of conditioned outdoor fresh air...

  17. Simulation study of dynamo structure in reversed field pinch

    International Nuclear Information System (INIS)

    Nagata, A.; Sato, K.I.; Ashida, H.; Amano, T.

    1992-10-01

    The dynamo structure in the reversed field pinch (RFP) is studied through the nonlinear dynamics of single-helicity mode. Simulation is concentrated upon the physical structure of nonlinear interactions of the plasma flow and magnetic fluctuation. The result indicates that when the initial equilibrium profile is deformed by resistive diffusion, the radial flow is driven near the core of the plasma. As this flow forms a vortex structure and magnetic fluctuation grows radially, the dynamo electric field is spirally induced just inside the reversal surface and then the toroidal flux is increased. This dynamo electric field correlates to nonlinear evolution of the kinetic energy of m=1 mode, and the increase of the toroidal flux is originated in the growth process of the magnetic energy of this mode. Consequently, the RFP configuration can be sustained by the single-helicity evolution of m=1 mode alone, and the electric field induced by the interactions of the toroidal velocity and the radial magnetic field is the most dominant source on the dynamo action. (author)

  18. Study of the cosmological evolution of the magnetic field

    International Nuclear Information System (INIS)

    Dubois, Yohan

    2008-01-01

    In numerical models within the standard hierarchical structure formation, galaxies contain too much stars in comparison with observations. That is called the over-cooling dilemma. I have studied the galactic wind formation produced by the supernovae explosions using the numerical code RAMSES and a bunch of analytical tools. I have underlined the central role of the infalling gas accreting on galactic disks, and I have determined the conditions under which this accretion can prevent any gas ejection on large scales. It appears that winds are unable to elucidate the over-cooling problem in quiescent star forming galaxies. On the other hand, dwarf galaxies, capable to form such super-winds, are responsible for the metallic and magnetic enrichment of the extra-galactic medium. Using the same numerical tool, I performed the first simulation of the formation of a galactic win with magnetic fields. Numerical simulations of galactic wind formation with magnetic fields show the necessity of some amplification process occurring in galaxies: associated to a strong stellar dynamo, supernovae explosions can originate the residual magnetic field of the Universe. The magnetic field present on large scales is therefore amplified when the hot gas of the galaxy cluster collapses. By achieving the first magnetic cosmological simulation of the formation of a cluster and its galaxies, I was able to point out the necessity of accounting for the cooling processes to properly describe the magnetic field evolution inside the cluster core and to reconcile simulations with observational values. (author) [fr

  19. Study optimizes gas lift in Gulf of Suez field

    Energy Technology Data Exchange (ETDEWEB)

    Abdel-Waly, A.A. [King Saud Univ., Riyadh (Saudi Arabia); Darwish, T.A.; Osman Salama, A. [Cairo Univ., Giza (Egypt); El-Naggar, M. [Gulf of Suez Petroleum Co., Cairo (Egypt)

    1996-06-24

    A study using PVT data combined with fluid and multiphase flow correlations optimized gas lift in the Ramadan field, Nubia C, oil wells, in the Gulf of Suez. Selection of appropriate correlations followed by multiphase flow calculations at various points of injection (POI) were the first steps in the study. After determining the POI for each well from actual pressure and temperature surveys, the study constructed lift gas performance curves for each well. Actual and optimum operating conditions were compared to determine the optimal gas lift. The study indicated a net 2,115 bo/d could be gained from implementing its recommendations. The actual net oil gained as a result of this optimization and injected gas reallocation was 2,024 bo/d. The paper discusses the Ramadan field, fluid properties, multiphase flow, production optimization, and results.

  20. Study of the performance of Micromegas detectors in magnetic field

    Science.gov (United States)

    Dimitrios, Sampsonidis

    2018-02-01

    Resistive Micromegas (MICRO MEsh GAseous Structure) detectors have been chosen by the ATLAS collaboration at LHC for the high luminosity upgrade, due to their capability to maintain full efficiency and high spatial resolution at high occupancy, for tracking muons in the forward region of the detector. The Inner Muon Station, in the high-rapidity region, the so called New Small Wheel (NSW), will be composed of micromegas detectors that will have to maintain good performance in the presence of magnetic field of up to about 0.3 T. The response of micromegas detectors is affected by the magnetic field, where the deflection of the drift electrons is described by the Lorentz angle, resulting in a bias in the reconstructed track position. Several test-beam campaigns have been performed to test the behaviour of small size resistive micromegas prototypes (10×10 cm2) in magnetic fields up to 1 T, using high momentum muon and hadron beams at CERN. These studies are performed in order to validate the capability of the chambers to provide unbiased tracks in the NSW conditions. Measurements of the Lorentz angle and drift velocity as a function of the magnetic field are presented and both are compared to expectations based on Garfield-Magboltz simulations. Several methods to correct the position bias are applied, based on the chamber configuration or on the knowledge of the local value of the magnetic field. The results of these studies are presented together with an overall discussion of the Micromegas tracking capability in magnetic field.

  1. Study of the performance of Micromegas detectors in magnetic field

    Directory of Open Access Journals (Sweden)

    Dimitrios Sampsonidis

    2018-01-01

    Full Text Available Resistive Micromegas (MICRO MEsh GAseous Structure detectors have been chosen by the ATLAS collaboration at LHC for the high luminosity upgrade, due to their capability to maintain full efficiency and high spatial resolution at high occupancy, for tracking muons in the forward region of the detector. The Inner Muon Station, in the high-rapidity region, the so called New Small Wheel (NSW, will be composed of micromegas detectors that will have to maintain good performance in the presence of magnetic field of up to about 0.3 T. The response of micromegas detectors is affected by the magnetic field, where the deflection of the drift electrons is described by the Lorentz angle, resulting in a bias in the reconstructed track position. Several test-beam campaigns have been performed to test the behaviour of small size resistive micromegas prototypes (10×10 cm2 in magnetic fields up to 1 T, using high momentum muon and hadron beams at CERN. These studies are performed in order to validate the capability of the chambers to provide unbiased tracks in the NSW conditions. Measurements of the Lorentz angle and drift velocity as a function of the magnetic field are presented and both are compared to expectations based on Garfield-Magboltz simulations. Several methods to correct the position bias are applied, based on the chamber configuration or on the knowledge of the local value of the magnetic field. The results of these studies are presented together with an overall discussion of the Micromegas tracking capability in magnetic field.

  2. Single- and multi-photon ionization studies of organosulfur species

    Energy Technology Data Exchange (ETDEWEB)

    Cheung, Yu -San [Iowa State Univ., Ames, IA (United States)

    1999-02-12

    Accurate ionization energies (IE`s) for molecular species are used for prediction of chemical reactivity and are of fundamental importance to chemists. The IE of a gaseous molecule can be determined routinely in a photoionization or a photoelectron experiment. IE determinations made in conventional photoionization and photoelectron studies have uncertainties in the range of 3--100 meV (25--250 cm-1). In the past decade, the most exciting development in the field of photoionization and photoelectron spectroscopy has been the availability of high resolution, tunable ultraviolet (UV) and vacuum ultraviolet (VUV) laser sources. The laser pulsed field ionization photoelectron (PFI-PE) scheme is currently the state-of-the-art photoelectron spectroscopic technique and is capable of providing photoelectron energy resolution close to the optical resolution. The author has focused attention on the photoionization processes of some sulfur-containing species. The studies of the photoionization and photodissociation on sulfur-containing compounds [such as CS2, CH3SH, CH3SSCH3, CH3CH2SCH2CH3, HSCH2CH2SH and C4H4S (thiophene) and sulfur-containing radicals, such as HS, CS, CH3S, CH3CH2S and CH3SS], have been the major subjects in the group because sulfur is an important species contributing to air pollution in the atmosphere. The modeling of the combustion and oxidation of sulfur compounds represents important steps for the control of both the production and the elimination of sulfur-containing pollutants. Chapter 1 is a general introduction of the thesis. Chapters 2 and 6 contain five papers published in, or accepted for publication in, academic periodicals. In Chapter 7, the progress of the construction in the laboratory of a new vacuum ultraviolet laser system equipped with a reflectron mass

  3. A study of supersonic mixing flow field with ramp injector

    Science.gov (United States)

    Yamane, Yoshiyuki; Sawaguchi, Seiichi; Ando, Yasunori; Aso, Shigeru; Fukuda, Masahiro

    1994-06-01

    The purposes of the present paper are to investigate the structure of supersonic mixing flow field in ram/scramjet combustor and to develop the CFD code which will be used for the design of the combustor. One type of parallel injection method with ramp injector has been studied numerically and experimentally. The patterns of shock waves obtained by numerical simulations agreed with experimental results in schlieren photograph. Comparisons of static pressure distributions on the wall surface showed good agreement qualitatively. Numerical results captured the structures of flow field clearly, which were generating process of a pair of streamwise vortices and vortical roll-up of the jet. Oblique shocks made injectant gas lift off from wall surface, as found in calculations and experiments. According to these results, it could be said that the CFD code used in this study was useful for investigation of fuel-air mixing in supersonic flow field with parallel injection. From the numerical results, it was confirmed that the streamwise vortices generated by ramp injector and interaction between mixing field and oblique shocks were key factors for enhancement of fuel-air mixing in ram/scramjet combustor.

  4. Urban Dispersion Program Overview and MID05 Field Study Summary

    Energy Technology Data Exchange (ETDEWEB)

    Allwine, K Jerry; Flaherty, Julia E.

    2007-07-31

    The Urban Dispersion Program (UDP) was a 4-year project (2004–2007) funded by the U.S. Department of Homeland Security with additional support from the Defense Threat Reduction Agency. The U.S. Environmental Protection Agency (EPA) also contributed to UDP through funding a human-exposure component of the New York City (NYC) field studies in addition to supporting an EPA scientist in conducting modeling studies of NYC. The primary goal of UDP was to improve the scientific understanding of the flow and diffusion of airborne contaminants through and around the deep street canyons of NYC. The overall UDP project manager and lead scientist was Dr. Jerry Allwine of Pacific Northwest National Laboratory. UDP had several accomplishments that included conducting two tracer and meteorological field studies in Midtown Manhattan.

  5. Study of Geomagnetic Field Response to Solar Wind Forcing

    Science.gov (United States)

    Kim, S.; Li, X.; Damas, M. C.; Ngwira, C.

    2017-12-01

    The solar wind is an integral component of space weather that has a huge impact on the near-Earth space conditions, which can in turn adversely impact technological infrastructure. By analyzing solar wind data, we can investigate the response of the Earth's magnetic field to changes in solar wind conditions, such as dynamic pressure, speed, and interplanetary magnetic fields (IMF). When a coronal mass ejection (CME) hits the Earth's magnetosphere, it compresses the dayside magnetosphere, which leads to SSC (Sudden Storm Commencement) seen in Dst or SYM-H index. Dst and SYM-H index are a measure of geomagnetic storm intensity that represents the magnetic field perturbations in the equatorial region originating from ring current. In this study, we focused on SSC intervals with sudden density increase, density, greater than 10 n/cc from 2000 to 2015 using data obtained from the NASA CDAWEB service. A total of 1,049 events were picked for this project. Then using INTERMAGNET service, corresponding horizontal component of magnetic field data were collected from several stations located in equatorial region, mid-latitude region, high-latitude region on the day-side and night-side of Earth. Using MATLAB, we calculated the rate of change of magnetic fields (dB/dt) for each station and each event. We found that in most cases, the sudden increase in proton density is associated with large changes in magnetic fields, dB/dt. The largest magnetic field changes were observed on the day-side than night-side at high latitudes. Interestingly, some exceptions were found such that greater dB/dt was found on night-side than day-side during some events, particularly at high latitudes. We suspect these are driven by magnetospheric substorms, which are manifested by an explosive release of energy in the local midnight sector. The next step will be creating the statistical form to see the correlation between proton density changes and magnetic field changes.

  6. Ion chemistry of some organic molecules studied by field ionization and field desorption mass spectrometry

    International Nuclear Information System (INIS)

    Greef, J. van der.

    1980-01-01

    The chemistry of isolated ions in the gas phase is strongly dependent on the internal energy which they have required upon formation. Since also the average lifetime of an ion depends on its internal energy, ion lifetime studies have been employed for many years to obtain a better insight in the relation between the chemistry and internal energy of gas phase ions. A very powerful tool for such studies is the field ionization kinetic (FIK) method, because it can provide a time-resolved picture of decompositions of ions with lifetimes varying from 10 -11 to 10 -5 s. The FIK method has been used in combination with 2 H, 13 C and 15 N labelling for mechanistic studies on the fragmentation of some selected ionised organic molecules. (Auth.)

  7. Field Artillery Ammunition Processing System (FAAPS) concept evaluation study

    Energy Technology Data Exchange (ETDEWEB)

    Kring, C.T.; Babcock, S.M.; Watkin, D.C.; Oliver, R.P.

    1992-06-01

    The Field Artillery Ammunition Processing System (FAAPS) is an initiative to introduce a palletized load system (PLS) that is transportable with an automated ammunition processing and storage system for use on the battlefield. System proponents have targeted a 20% increase in the ammunition processing rate over the current operation while simultaneously reducing the total number of assigned field artillery battalion personnel by 30. The overall objective of the FAAPS Project is the development and demonstration of an improved process to accomplish these goals. The initial phase of the FAAPS Project and the subject of this study is the FAAPS concept evaluation. The concept evaluation consists of (1) identifying assumptions and requirements, (2) documenting the process flow, (3) identifying and evaluating technologies available to accomplish the necessary ammunition processing and storage operations, and (4) presenting alternative concepts with associated costs, processing rates, and manpower requirements for accomplishing the operation. This study provides insight into the achievability of the desired objectives.

  8. Intergenerational Transmission of Gender Segregation: How Parents' Occupational Field Affects Gender Differences in Field of Study Choices

    Science.gov (United States)

    Vleuten, Maaike; Jaspers, Eva; Maas, Ineke; van der Lippe, Tanja

    2018-01-01

    The study explores how parents' occupational field affects gender differences in educational fields. On the one hand, the theory of direct transfer predicts that adolescents enter fields similar to those of their parents because of intergenerational transmission of occupation-specific resources and that adolescents are more likely to draw upon the…

  9. Canine parvovirus in vaccinated dogs: a field study.

    Science.gov (United States)

    Miranda, C; Thompson, G

    2016-04-16

    The authors report a field study that investigated the canine parvovirus (CPV) strains present in dogs that developed the disease after being vaccinated. Faecal samples of 78 dogs that have been vaccinated against CPV and later presented with clinical signs suspected of parvovirus infection were used. Fifty (64.1 per cent) samples tested positive by PCR for CPV. No CPV vaccine type was detected. The disease by CPV-2b occurred in older and female dogs when compared with that by CPV-2c. The clinical signs presented by infected dogs were similar when any of both variants were involved. In most cases of disease, the resulting infection by field variants occurred shortly after CPV vaccination. Two dogs that had been subjected to a complete vaccination schedule and presented with clinical signs after 10 days of vaccination, had the CPV-2c variant associated. The phylogenetic studies showed a close relationship of the isolates in vaccinated dogs to European field strains. Despite the limited sample size in this study, the findings point to the significance of the continuous molecular typing of the virus as a tool to monitor the prevalent circulating CPV strains and access the efficacy of current vaccines. Adjustments on the vaccine types to be used may have to be evaluated again according to each epidemiological situation in order to achieve the dog's optimal immune protection against CPV.

  10. Science and ecological literacy in undergraduate field studies education

    Science.gov (United States)

    Mapp, Kim J.

    There is an ever-increasing number of issues that face our world today; from climate change, water and food scarcity, to pollution and resource extraction. Science and ecology play fundamental roles in these problems, and yet the understanding of these fields is limited in our society (Miller, 2002; McBride, Brewer, Berkowitz, and Borrie, 2013). Across the nation students are finishing their undergraduate degrees and are expected to enter the workforce and society with the skills needed to succeed. The deficit of science and ecological literacy in these students has been recognized and a call for reform begun (D'Avanzo, 2003 and NRC, 2009). This mixed-methods study looked at how a field studies course could fill the gap of science and ecological literacy in undergraduates. Using grounded theory, five key themes were data-derived; definitions, systems thinking, human's role in the environment, impetus for change and transference. These themes where then triangulated for validity and reliability through qualitative and quantitative assessments. A sixth theme was also identified, the learning environment. Due to limited data to support this themes' development and reliability it is discussed in Chapter 5 to provide recommendations for further research. Key findings show that this field studies program influenced students' science and ecological literacy through educational theory and practice.

  11. 1992-93 Results of geomorphological and field studies Volcanic Studies Program, Yucca Mountain Project

    International Nuclear Information System (INIS)

    Wells, S.G.

    1993-10-01

    Field mapping and stratigraphic studies were completed of the Black Tank volcanic center, which represents the southwestern most eruptive center in the Cima volcanic field of California. The results of this mapping are presented. Contacts between volcanic units and geomorphic features were field checked, incorporating data from eight field trenches as well as several exposures along Black Tank Wash. Within each of the eight trenches, logs were measured and stratigraphic sections were described. These data indicate that three, temporally separate volcanic eruptions occurred at the Black Tank center. The field evidence for significant time breaks between each stratigraphic unit is the presence of soil and pavement-bounded unconformities

  12. Reservoir engineering studies of the Cerro Prieto geothermal field

    Science.gov (United States)

    Goyal, K. P.; Lippmann, M. J.; Tsang, C. F.

    1982-09-01

    Reservoir engineering studies of the Cerro Prieto geothermal field began in 1978 under a five-year cooperative agreement between the US Department of Energy and the Comision Federal de Electricidad de Mexico, with the ultimate objective of simulating the reservoir to forecast its production capacity, energy longevity, and recharge capability under various production and injection scenarios. During the fiscal year 1981, attempts were made to collect information on the evolution history of the field since exploitation began; the information is to be used later to validate the reservoir model. To this end, wellhead production data were analyzed for heat and mass flow and also for changes in reservoir pressures, temperatures, and saturations for the period from March 1973 to November 1980.

  13. Field studies of radionuclide transport at the Chalk River Laboratories

    International Nuclear Information System (INIS)

    Champ, D.R.; Killey, R.W.D.; Moltyaner, G.L.

    1991-01-01

    In this paper the authors summarize the results of: in situ field column experiments to study the transport behaviour of several long-lived radionuclides, 4 natural gradient non-reactive radiotracer injection experiments at the Chalk River Laboratories (CRL) Twin Lake Tracer Test Site, and a model validation study that used data for 90 Sr from two well-defined contaminated groundwater flow systems at CRL. The paper also describes a current re-evaluation of radionuclide release and transport from a 1960 experimental burial (in a CRL sand aquifer) of glass blocks containing fission and activation products. (J.P.N.)

  14. Women Emoloyees’ Perceptions About Their Managers: A Field Study

    Directory of Open Access Journals (Sweden)

    İsmail BAKAN

    2013-12-01

    Full Text Available The leadership style of people in managerial positions has a significant impact on employee behavior and attitudes towards business. Therefore, finding out the perceptions of employees regarding their managers’ leadership style will guide to managers to display successful management. There are several distinctions in the literature as to the type of leadership. In this study, first the concept and types of leadership determined and then the autocratic, democratic and free reign leadership styles will be explained. In the second part of the study a field research, to measure the perceptions of women workers about their managers’ leadership style, will be included in the textile industry as leading sector in Kahramanmaras.

  15. Study On Aftershock Triggering In Consideration Of Tectonic Stress Field

    Science.gov (United States)

    Hu, C.; Cai, Y.

    2007-12-01

    : The occurrence of earthquake is related to the strength of rock and tectonic stress field. The seismic risk factor (SRF),D=\\left|{τn }\\right|/(μσn ) is proposed to describe the dangerous status of aftershock triggering in this paper. Dearthquakes, velocity field from GPS as well as geological survey. As one order of approximation, the magnitudes of the regional tectonic stress field can be estimated by the Coulomb failure criterion. Finite element method (FEM) and the concept of the factor D are used to study the aftershock triggering of the 1976 Tangshan Ms=7.8 earthquake. The results show that: (1) Most of the aftershocks triggered by the Tangshan earthquake occurred in the two-leaf-shaped regions of D≥ 1 near the north-east end of the main-shock fault. The largest leaf is about 100km long and 40km wide. (2) The areas of aftershock triggering predicted by the seismic risk factorD and Δ CFS (the changes in the Coulomb failure stress) are almost the same near the fault. The difference between them is that the aftershock area predicted by Δ CFS≥ 0 is too large and the area predicted by the factor D≥ 1 is limited. The areas of aftershock triggering predicted by Δ CFS≥ 0.04 MPa are nearly the same as those of D≥ 1 obtained by the study. (3) Sometimes Δ CFS =0.01MPa is taken as a low threshold of aftershock triggering. However, Δ CFS≥ 0 only means the probability increase of the earthquake triggering, not means the earthquake will occur. The earthquake occurrence is not only related to Δ CFS, but also to the tectonic stress field before the main-shock.

  16. Experimental studies of plasma wake-field acceleration and focusing

    International Nuclear Information System (INIS)

    Rosenzweig, J.B.; Cole, B.; Ho, C.; Argonne National Lab., IL

    1989-01-01

    More than four years after the initial proposal of the Plasma Wake-field Accelerator (PWFA), it continues to be the object of much investigation, due to the promise of the ultra-high accelerating gradients that can exist in relativistic plasma waves driven in the wake of charged particle beams. These large amplitude plasma wake-fields are of interest in the laboratory, both for the wealth of basic nonlinear plasma wave phenomena which can be studied, as well as for the applications of acceleration of focusing of electrons and positrons in future linear colliders. Plasma wake-field waves are also of importance in nature, due to their possible role in direct cosmic ray acceleration. The purpose of the present work is to review the recent experimental advances made in PWFA research at Argonne National Laboratory, in which many interesting beam and plasma phenomena have been observed. Emphasis is given to discussion of the nonlinear aspects of the PWFA beam-plasma interaction. 29 refs., 13 figs

  17. Wide-field ultraviolet imager for astronomical transient studies

    Science.gov (United States)

    Mathew, Joice; Ambily, S.; Prakash, Ajin; Sarpotdar, Mayuresh; Nirmal, K.; Sreejith, A. G.; Safonova, Margarita; Murthy, Jayant; Brosch, Noah

    2018-03-01

    Though the ultraviolet (UV) domain plays a vital role in the studies of astronomical transient events, the UV time-domain sky remains largely unexplored. We have designed a wide-field UV imager that can be flown on a range of available platforms, such as high-altitude balloons, CubeSats, and larger space missions. The major scientific goals are the variability of astronomical sources, detection of transients such as supernovae, novae, tidal disruption events, and characterizing active galactic nuclei variability. The instrument has a 80 mm aperture with a circular field of view of 10.8 degrees, an angular resolution of ˜22 arcsec, and a 240 - 390 nm spectral observation window. The detector for the instrument is a Microchannel Plate (MCP)-based image intensifier with both photon counting and integration capabilities. An FPGA-based detector readout mechanism and real time data processing have been implemented. The imager is designed in such a way that its lightweight and compact nature are well fitted for the CubeSat dimensions. Here we present various design and developmental aspects of this UV wide-field transient explorer.

  18. Nursing students’ satisfaction about their field of study

    Directory of Open Access Journals (Sweden)

    ASHRAFALSADAT HAKIM

    2014-04-01

    Full Text Available Introduction: Nowadays students’ opinion is considered as a necessary factor to evaluate quality in universities. This study was performed to evaluate the nursing students’ satisfaction about their field of study. Methods: The research population in this study consists of all the students of nursing studying at the second to fourth year of university (72 students. The data were collected from all the studied population. Data collection instrument was a research questionnaire. In this cross-sectional research, nursing students’ satisfaction (72 students in 6 major topics (situation of educational environment, situation of clinical environment, trainers, social image, relation to colleagues and management was studied. The data were analyzed in SPSS version 14, using quantitative variables and descriptive statistics including frequency distribution tables and diagrams. Results: The findings indicated that 83.3% of the students had little satisfaction as to the situation of educational environment, 47.2% about situation of clinical environment, 41.7% concerning the theoretical educational method by professors, and 41.7% as to the method of clinical education by clinical trainers. Also 47.2% were not that satisfied with the method of evaluation by the school professors, 80.6% with the method of relationship with colleagues and also 62.5% with the nursing social image. Moreover, findings indicated that 33.3% of the participants in this research were dissatisfied with the method of evaluation by clinical trainers and 50% with the method of nursing management. Conclusion: In the present study, most students had little satisfaction concerning their field of study. So it is necessary to make an attempt for continuous development of quality services.

  19. Development of installation for study of electrostatic fields

    Science.gov (United States)

    Kyrmakova, O. S.; Skoryupina, K. A.; Sechin, A. I.

    2017-08-01

    The safe installation for studying the model electrostatic fields in the model areas of the cyclone is developed. It is found that the induction neutralizer reduces the concentration of ethyl alcohol (ethanol) in the examined object. The distance between the charged region in the cyclone and the neutralizer is the correction value of the height of the corona needles that is characterized by the magnitude of the ignition energy of the medium in the cyclone. The research results can be used in the development of cyclone apparatus for explosive industries, as well as measures to reduce technological emissions into the environment.

  20. Cognition and sensation in very high static magnetic fields: a randomized case-crossover study with different field strengths.

    Science.gov (United States)

    Heinrich, Angela; Szostek, Anne; Meyer, Patric; Nees, Frauke; Rauschenberg, Jaane; Gröbner, Jens; Gilles, Maria; Paslakis, Georgios; Deuschle, Michael; Semmler, Wolfhard; Flor, Herta

    2013-01-01

    To establish the extent to which representative cognitive functions in subjects undergoing magnetic resonance (MR) imaging are acutely impaired by static magnetic fields of varying field strengths. This study was approved by the local ethics committee, and informed consent was obtained from all subjects. In this single-blind case-crossover study, 41 healthy subjects underwent an extensive neuropsychologic examination while in MR units of differing field strengths (1.5, 3.0, and 7.0 T), including a mock imager with no magnetic field as a control condition. Subjects were blinded to field strength. Tests were performed while subjects were lying still in the MR unit and while the examination table was moved. The tests covered a representative set of cognitive functions, such as memory, eye-hand coordination, attention, reaction time, and visual discrimination. Subjective sensory perceptions were also assessed. Effects were analyzed with a repeated-measures analysis of variance; the within-subject factors were field strength (0, 1.5, 3.0, and 7.0 T) and state (static, dynamic). Static magnetic fields were not found to have a significant effect on cognitive function at any field strength. However, sensory perceptions did vary according to field strength. Dizziness, nystagmus, phosphenes, and head ringing were related to the strength of the static magnetic field. Static magnetic fields as high as 7.0 T did not have a significant effect on cognition. RSNA, 2012

  1. Field study to evaluate radiation doses in dental practices

    International Nuclear Information System (INIS)

    Panzer, W.; Scheurer, C.

    1984-05-01

    An inexpensive and simple test device was developed and used in a field study to evaluate entrance dose, dose to an intra-oral film, filtration and field size under routine conditions in more than 150 dental practices. The test device consists of two films of different speed and a set of 5 thin copper filters for a filter analytical determination of the radiation quality. Dentists voluntarily participating in the study were asked to expose the test device like they usually do when examining a molar tooth. The main result was the evidence of a significant dose reduction compared to the findings of similar studies performed in 1970 and 1976. This reduction is due to a general shift to lower values and a complete disappearance of values above 45 mGy (5 R) which in 1970 were still more than 15%. In the same way the number of facilities showing insufficient filtration or collimation had decreased. Nevertheless, a large spread of dose values could still be observed, ranging from less than 0.45 mGy (50 mR) to more than 26 mGy (3 R), for the entrance dose. The most striking result, however, was that such an important parameter like the speed of the films used at the respective unit turned out to have no impact on the entrance dose. (orig./HP)

  2. Classroom HVAC: Improving ventilation and saving energy -- field study plan

    Energy Technology Data Exchange (ETDEWEB)

    Apte, Michael G.; Faulkner, David; Hodgson, Alfred T.; Sullivan, Douglas P.

    2004-10-14

    The primary goals of this research effort are to develop, evaluate, and demonstrate a very practical HVAC system for classrooms that consistently provides classrooms (CRs) with the quantity of ventilation in current minimum standards, while saving energy, and reducing HVAC-related noise levels. This research is motivated by the public benefits of energy efficiency, evidence that many CRs are under-ventilated, and public concerns about indoor environmental quality in CRs. This document provides a summary of the detailed plans developed for the field study that will take place in 2005 to evaluate the energy and IAQ performance of a new classroom HVAC technology. The field study will include measurements of HVAC energy use, ventilation rates, and IEQ conditions in 10 classrooms with the new HVAC technology and in six control classrooms with a standard HVAC system. Energy use and many IEQ parameters will be monitored continuously, while other IEQ measurements will be will be performed seasonally. Continuously monitored data will be remotely accessed via a LonWorks network. Instrument calibration plans that vary with the type of instrumentation used are established. Statistical tests will be employed to compare energy use and IEQ conditions with the new and standard HVAC systems. Strengths of this study plan include the collection of real time data for a full school year, the use of high quality instrumentation, the incorporation of many quality control measures, and the extensive collaborations with industry that limit costs to the sponsors.

  3. Radiobiology at GANIL: local project and others fields studied

    International Nuclear Information System (INIS)

    Anon.

    2001-01-01

    This article reviews the research that is led in the field of radiobiology using heavy ions at Ganil. Our first studies with heavy ions were mainly focused on chromosome rearrangements induced in irradiated human cells. We analyzed R-banded chromosome rearrangements in human lymphocytes irradiated with several ions having a wide range of linear energy transfer (LET). Damage increased with the fluence and LET but at the higher LET, damage decreased for fluences above 10 7 particles/cm 2 . Chromosome rearrangements of high complexity involve several breaks. DNA strand breaks are concentrated in localized areas and their complexity is greatly increased by high-LET radiations. Our study was mainly qualitative and we showed a clear shift and dispersion of comet distribution towards high tail moments when particle LET and fluence increased. The higher the LET, the greater the level of DNA breaks observed for the same fluence. Gamma rays were more effective in producing DNA breaks than all the ions, at least in the lower dose range. In addition to early damage, high-LET irradiation also induces delayed lesions, and genomic instability occurs after many generations in the progeny of irradiated cells. We observed delayed chromosome instability on human dermis fibroblasts exposed to heavy ions, neon, argon, and lead but not after gamma rays. Various fields of radiobiology are now explored by different research groups. One of the studies aims to detect locally multiple damage sites (LMDS) formed in DNA after exposure to heavy ions. (A.C.)

  4. Modeling study of the Pauzhetsky geothermal field, Kamchatka, Russia

    Energy Technology Data Exchange (ETDEWEB)

    Kiryukhin, A.V. [Institute of Volcanology, Kamchatsky (Russian Federation); Yampolsky, V.A. [Kamchatskburgeotermia State Enterprise, Elizovo (Russian Federation)

    2004-08-01

    Exploitation of the Pauzhetsky geothermal field started in 1966 with a 5 MW{sub e} power plant. A hydrogeological model of the Pauzhetsky field has been developed based on an integrated analysis of data on lithological units, temperature, pressure, production zones and natural discharge distributions. A one-layer 'well by well' model with specified vertical heat and mass exchange conditions has been used to represent the main features of the production reservoir. Numerical model development was based on the TOUGH2 code [Pruess, 1991. TOUGH2 - A General Purpose Numerical Simulator for Multiphase Fluid and Heat Flow, Lawrence Berkeley National Laboratory Report, Berkeley, CA; Pruess et al., 1999. TOUGH2 User's Guide, Version 2.0, Report LBNL-43134, Lawrence Berkeley National Laboratory, Berkeley, CA] coupled with tables generated by the HOLA wellbore simulator [Aunzo et al., 1991. Wellbore Models GWELL, GWNACL, and HOLA, Users Guide, Draft, 81 pp.]. Lahey Fortran-90 compiler and computer graphical packages (Didger-3, Surfer-8, Grapher-3) were also used to model the development process. The modeling study of the natural-state conditions was targeted on a temperature distribution match to estimate the natural high-temperature upflow parameters: the mass flow-rate was estimated at 220 kg/s with enthalpy of 830-920 kJ/kg. The modeling study for the 1964-2000 exploitation period of the Pauzhetsky geothermal field was targeted at matching the transient reservoir pressure and flowing enthalpies of the production wells. The modeling study of exploitation confirmed that 'double porosity' in the reservoir, with a 10-20% active volume of 'fractures', and a thermo-mechanical response to reinjection (including changes in porosity due to compressibility and expansivity), were the key parameters of the model. The calibrated model of the Pauzhetsky geothermal field was used to forecast reservoir behavior under different exploitation scenarios for

  5. Fog-82: A Cooperative Field Study of Radiation Fog.

    Science.gov (United States)

    Meyer, Michael B.; Garland Lala, G.; Jiusto, James E.

    1986-07-01

    The Cloud Physics Section of the Atmospheric Sciences Research Center-State University of New York at Albany conducted a cooperative field study (FOG-82) during the autumn of 1982 as part of an ongoing radiation-fog research program. A computer-controlled data-acquisition system consisting of sophisticated soil, surface, and boundary-layer sensors, as well as contemporary aerosol and droplet probes was developed. These data are being used to address a variety of critical problems related to radiation-fog evolution.Scientists from 10 universities and research laboratories participated in portions of FOG-82. Research objectives included studies of fog mesoscale meteorology, radiation studies, low-level water budget, vertical fog structure, fog supersaturation, condensation nuclei, and fog-water chemistry, as well as radiation-fog life cycles. A comprehensive description of the FOG-82 program and objectives is presented.

  6. Field study of disposed solid wastes from advanced coal processes

    International Nuclear Information System (INIS)

    1992-01-01

    Radian Corporation and the North Dakota Energy and Environmental Research Center (EERC) are funded to develop information to be used by private industry and government agencies for managing solid wastes produced by advanced coal combustion processes. This information will be developed by conducting several field studies on disposed wastes from these processes. Data will be collected to characterize these wastes and their interactions with the environments in which they are disposed. Three sites were selected for the field studies: Colorado Ute's fluidized bed combustion (FBC) unit in Nucla, Colorado; Ohio Edison's limestone injection multistage burner (LIMB) retrofit in Lorain, Ohio; and Freeman United's mine site in central Illinois with wastes supplied by the nearby Midwest Grain FBC unit. During the past year, field monitoring and sampling of the four landfill test cases constructed in 1989 and 1991 has continued. Option 1 of the contract was approved last year to add financing for the fifth test case at the Freeman United site. The construction of the Test Case 5 cells is scheduled to begin in November, 1992. Work during this past year has focused on obtaining data on the physical and chemical properties of the landfilled wastes, and on developing a conceptual framework for interpreting this information. Results to date indicate that hydration reactions within the landfilled wastes have had a major impact on the physical and chemical properties of the materials but these reactions largely ceased after the first year, and physical properties have changed little since then. Conditions in Colorado remained dry and no porewater samples were collected. In Ohio, hydration reactions and increases in the moisture content of the waste tied up much of the water initially infiltrating the test cells

  7. Study of the interaction of atoms with strong laser fields

    International Nuclear Information System (INIS)

    Edwards, M.

    1984-01-01

    Three aspects of the interactions of atoms with high intensity laser fields were treated. All three were motivated by experiment. The first investigation was prompted by a recent experiment (Kruit et al. 1983) involving multiphoton ionization of Xe. In this experiment it was found that the photoelectron energy spectrum contained peaks that corresponded to the absorption of more than the minimum number of photons required to ionize the atom. A model approximation here showed good qualitative agreement with experiment. An experiment (Grove et al. 1977) designed to test a theoretical calculation of the dynamical Stark effect stimulated the second part of this thesis, namely: a study of how an adiabatically and near-adiabatically changing field intensity affects the resonance fluorescence spectrum of a two-level atom. It was found that there is an asymmetry in the spectrum for off-resonance excitation produced because the field turn-on repopulates the dressed state that is depopulated by spontaneous emission. The third part of this thesis was based on an experiment (Granneman and Van der Wiel 1976) that attempted to verify a perturbation calculation of the two-photon ionization cross section of Cs. A discrepancy of four orders of magnitude near a minimum in the cross section was found between theory and experiment. To explain this discrepancy it was suggested (Armstrong and Beers 1977) that the effective order of nonlinearity (k) for this process varied significantly around the minimum. This study involves a perturbation calculation of k. It was found that k varies rapidly around the minimum, and that this variation should be experimentally observable for laser intensities of the order of tens of GW cm -2

  8. An Optimization of Pulsed ElectroMagnetic Fields Study

    Science.gov (United States)

    Goodwin, Thomas J.

    2006-01-01

    To date, in our research we have focused on the use of normal human neuronal progenitor (NHNP) cells because of their importance in human nervous system regeneration, development and maintenance, but we have developed 2-D and 3-D bioreactors that can accommodate any cell line. In this Project, we will include the use of tissues important for physiological regeneration: Human osteoblasts or chondrocytes, and vascular cells. Our initial results with the NHNP cells were quite startling using extremely low-level electromagnetic fields (5 microtesla at 10Hz; 6mA). The low-amplitude, rapidly time-varying electromagnetic fields exert a very potent effect on the proliferation, morphology, and gene expression of the cells in culture, both in standard 2-dimensional culture plates as well as cells organized into 3-dimensional tissue-like assemblies (TLAs) in a 3D bioreactor. We have replicated our preliminary results many, many times, have analyzed the gene expression using gene arrays (followed by Luminex analysis for protein production), and have monitored cell proliferation, orientation, morphology, and glucose metabolism, and we are confident that we have a stable and reliable model to study the control of high-level cellular processes by application of low-amplitude, time varying electromagnetic fields (TVEMF) (1, 2). In additional studies at the University of Michigan, we have been able to generate functional in vitro engineered mammalian skeletal muscle, and have employed nerve-muscle co-culture techniques to promote axonal sprouting. We believe that nearly all tissues, in particular, neural, are susceptible to the influences of low-level TVEMF.

  9. Study of filtration capacity parameters during oil and gas field exploitation based on geophysical field data

    Energy Technology Data Exchange (ETDEWEB)

    Buryakovskiy, L.A.; Badalov, T.A.; Palatnik, G.G.

    1981-01-01

    Formation parameters are determined using petrophysical relations between geophysical and field parameters. One method of forecasting is used to make a mathematical model. The model is described. The models were used to define porosity and permeability of the rock in horizon I in the Mishordag and Kyurovdag fields.

  10. Effective potential study of the Diluted Antiferromagnet in a Field

    Science.gov (United States)

    Yllanes, David; Fernandez, L. A.; Martin-Mayor, V.

    2011-03-01

    We present a numerical study of the three-dimensional Diluted Antiferromagnet in a Field (DAFF), one of the experimental realizations of the Random Field Ising Model. We work in a constrained ensemble (tethered ensemble) where the Helmholtz effective potential is featured, rather than the free energy. Our method cures the problem of a strong violation of self-averaging, thus allowing us to compute the correlation length for systems sizes up to L = 32 . This quantity, when measured in units of the lattice size, is independent of the system size at the critical point, a strong indication of a second-order phase transition. This scale invariance allows us to apply finite-size scaling in the form of Nightingale's phenomenological renormalization. We obtain accurate estimates of the critical exponents. Since our method reconstructs the effective potential, we can also compute accurately the hyperscaling violation exponent. We perform as well an investigation of the geometrical properties of the instanton-like configurations, namely, the minimal cost configurations joining the two ordered phases. This study sheds light on previous claims of a first-order phase transition in this system.

  11. Studying the field induced breakup of acoustically levitated drops

    Science.gov (United States)

    Warschat, C.; Riedel, J.

    2017-10-01

    Coulomb fission of charged droplets (The terms drop and droplet are often used synonymous. Throughout this manuscript, to avoid confusion, the terms drop and droplet will be used for liquid spheres with radii in the millimeter range and the micrometer range, respectively. In our experiments, the first correspond to the parent drop while the latter describes the ejected progeny droplets.) is a well-studied natural phenomenon. Controlled droplet fission is already successfully employed in several technological applications. Still, since the occurring surface rupture relies on the exact understanding and description of the liquid gas boundary, some details are still under debate. Most empirical systematic studies observe falling micrometer droplets passing through the electric field inside a plate capacitor. This approach, although easily applicable and reliable, limits the experimental degrees of freedom regarding the observable time and the maximum size of the drops and can only be performed in consecutive individual observations of different subsequent drops. Here we present a novel setup to study the field induced breakup of acoustically levitated drops. The design does not bear any restrictions towards the temporal window of observation, and allows handling of drops of a tunable radius ranging from 10 μm to several millimeters and a real-time monitoring of one single drop. Our comprehensive study includes a time resolved visual inspection, laser shadowgraphy, laser induced fluorescence imaging, and ambient mass spectrometric interrogation of the nascent Taylor cone. The results shown for a millimeter sized drop, previously inaccessible for Coulomb fission experiments, are mostly comparable with previous results for smaller drops. The major difference is the time scale and the threshold potential of the drop rupture. Both values, however, resemble theoretically extrapolations to the larger radius. The technique allows for a systematic study of breakup behavior of

  12. Pulsed field studies of magnetotransport in semiconductor heterostructures

    International Nuclear Information System (INIS)

    Dalton, K.S.H.

    1999-01-01

    High field magnetotransport in two classes of semiconductor heterostructures has been studied: parallel transport in InAs/(Ga,In)Sb double heterojunctions and superlattices at low temperatures (300 mK-4.2 K), and vertical transport in GaAs/AlAs short-period superlattices at 150-300 K. The experiments mainly used the Oxford pulsed magnet (∼45 T, ∼15 ms pulses). The development of the data acquisition system and experimental techniques for magnetotransport are described, including corrections to the data, required because of the rapidly changing magnetic field. Previous studies of magnetotransport in InAs/GaSb double heterojunctions are reviewed: this electron-hole system shows compensated quantum Hall plateaux, with ρ xy dips accompanied by 'anomalous' peaks in σ xx . New data show a peak between ν=1 plateaux; this behaviour and the temperature dependence of the 'anomalous' σ xx peaks are explained by considering the movement of the Fermi level amongst anticrossing electron- and hole-like levels. InAs/(Ga,In)Sb superlattices with electron:hole density ratios close to 1 exhibit large oscillations in the resistivity (maxima typically ∼20-30 x higher than minima) and conductivity components. Deep minima in ρ xy alternate with low-integer plateaux. The magnetotransport in various ideal structures is considered, to explain the experimental results. The growth of a novel structure has allowed clearer observation of the behaviour of ρ xx (giant maxima) and ρ xy (zeroes or maxima) when the contributions from each well to σ xx and σ xy approach zero. Measurements of the high field magnetotransport peak positions show that the band overlap is increased by growing 'InSb' rather than 'GaAs' interfaces (∼20% increase), increasing the indium in the (Ga,In)Sb (∼30% increase per 10% In), or growing along [111] instead of [001] (∼30% increase). Magnetophonon resonance in short-period GaAs/AlAs superlattices causes strong, electric field-dependent vertical

  13. Field study of sound exposure by personal stereo

    DEFF Research Database (Denmark)

    Ordoñez, Rodrigo Pizarro; Reuter, Karen; Hammershøi, Dorte

    2006-01-01

    A number of large scale studies suggest that the exposure level used with personal stereo systems should raise concern. High levels can be produced by most commercially available mp3 players, and they are generally used in high background noise levels (i.e., while in a bus or rain). A field study...... of habitual use, estimation of listening levels and exposure levels, and assessment of their state of hearing, by either threshold determination or OAE measurement, with a special view to the general validity of the results (uncertainty factors and their magnitude)....... on young people's habitual sound exposure to personal stereos has been carried out using a measurement method according to principles of ISO 11904-2:2004. Additionally the state of their hearing has also been assessed. This presentation deals with the methodological aspects relating to the quantification...

  14. Rapid Fielding: Case Study Concerning the Fielding of the Multiple Launch Rocket System (MLRS) M270A1 to 2d Battalion 4th Field Artillery Fort Sill, Oklahoma

    National Research Council Canada - National Science Library

    Saiz, Evangeline M

    2006-01-01

    .... This case study investigates one aspect of Army Transformation, accelerated fielding, to determine whether the Army's materiel fielding program properly supports rapidly fielding of essential major...

  15. Prospective cohort studies of shigellosis during military field training.

    Science.gov (United States)

    Cohen, D; Sela, T; Slepon, R; Yavzori, M; Ambar, R; Orr, N; Robin, G; Shpielberg, O; Eldad, A; Green, M

    2001-02-01

    Epidemiological and clinical features of shigellosis occurring among cohorts of Israeli recruits followed-up for 3-6 months during the summer field training of years 1993-1997 were studied. The incidence rate of culture-proven shigellosis was the highest (78 cases per 1,000 recruits) in 1996 and the lowest (13 cases per 1,000 recruits) in 1995. Shigella sonnei (152 isolates) and Shigella flexneri (151 isolates) were the most common species. Fifty percent of the patients with shigellosis had fever (>37.5 degrees C), compared to only 18% of the subjects with other diarrheal diseases (P < 0.001). The duration of illness was longer among subjects with shigellosis than among those with other diarrheal diseases (P < 0.001). Illness due to Shigella flexneri was more severe than illness caused by Shigella sonnei.

  16. Coherent error study in a retarding field energy analyzer

    International Nuclear Information System (INIS)

    Cui, Y.; Zou, Y.; Reiser, M.; Kishek, R.A.; Haber, I.; Bernal, S.; O'Shea, P.G.

    2005-01-01

    A novel cylindrical retarding electrostatic field energy analyzer for low-energy beams has been designed, simulated, and tested with electron beams of several keV, in which space charge effects play an important role. A cylindrical focusing electrode is used to overcome the beam expansion inside the device due to space-charge forces, beam emittance, etc. In this paper, we present the coherent error analysis for this energy analyzer with beam envelope equation including space charge and emittance effects. The study shows that this energy analyzer can achieve very high resolution (with relative error of around 10 -5 ) if taking away the coherent errors by using proper focusing voltages. The theoretical analysis is compared with experimental results

  17. Communication Problems in Requirements Engineering: A Field Study

    Science.gov (United States)

    Al-Rawas, Amer; Easterbrook, Steve

    1996-01-01

    The requirements engineering phase of software development projects is characterized by the intensity and importance of communication activities. During this phase, the various stakeholders must be able to communicate their requirements to the analysts, and the analysts need to be able to communicate the specifications they generate back to the stakeholders for validation. This paper describes a field investigation into the problems of communication between disparate communities involved in the requirements specification activities. The results of this study are discussed in terms of their relation to three major communication barriers: (1) ineffectiveness of the current communication channels; (2) restrictions on expressiveness imposed by notations; and (3) social and organizational barriers. The results confirm that organizational and social issues have great influence on the effectiveness of communication. They also show that in general, end-users find the notations used by software practitioners to model their requirements difficult to understand and validate.

  18. Effects of Bluetooth device electromagnetic field on hearing: pilot study.

    Science.gov (United States)

    Balachandran, R; Prepageran, N; Prepagaran, N; Rahmat, O; Zulkiflee, A B; Hufaida, K S

    2012-04-01

    The Bluetooth wireless headset has been promoted as a 'hands-free' device with a low emission of electromagnetic radiation. To evaluate potential changes in hearing function as a consequence of using Bluetooth devices, by assessing changes in pure tone audiography and distortion production otoacoustic emissions. Prospective study. Thirty adult volunteers were exposed to a Bluetooth headset device (1) on 'standby' setting for 6 hours and (2) at full power for 10 minutes. Post-exposure hearing was evaluated using pure tone audiography and distortion production otoacoustic emission testing. There were no statistically significant changes in hearing, as measured above, following either exposure type. Exposure to the electromagnetic field emitted by a Bluetooth headset, as described above, did not decrease hearing thresholds or alter distortion product otoacoustic emissions.

  19. Nonperturbative studies of quantum field theories on noncommutative spaces

    International Nuclear Information System (INIS)

    Volkholz, J.

    2007-01-01

    This work deals with three quantum field theories on spaces with noncommuting position operators. Noncommutative models occur in the study of string theories and quantum gravity. They usually elude treatment beyond the perturbative level. Due to the technique of dimensional reduction, however, we are able to investigate these theories nonperturbatively. This entails translating the action functionals into a matrix language, which is suitable for numerical simulations. First we explore the λφ 4 model on a noncommutative plane. We investigate the continuum limit at fixed noncommutativity, which is known as the double scaling limit. Here we focus especially on the fate of the striped phase, a phase peculiar to the noncommutative version of the regularized λφ 4 model. We find no evidence for its existence in the double scaling limit. Next we examine the U(1) gauge theory on a four-dimensional spacetime, where two spatial directions are noncommutative. We examine the phase structure and find a new phase with a spontaneously broken translation symmetry. In addition we demonstrate the existence of a finite double scaling limit which confirms the renormalizability of the theory. Furthermore we investigate the dispersion relation of the photon. In the weak coupling phase our results are consistent with an infrared instability predicted by perturbation theory. If the translational symmetry is broken, however, we find a dispersion relation corresponding to a massless particle. Finally, we investigate a supersymmetric theory on the fuzzy sphere, which features scalar neutral bosons and Majorana fermions. The supersymmetry is exact in the limit of infinitely large matrices. We investigate the phase structure of the model and find three distinct phases. Summarizing, we study noncommutative field theories beyond perturbation theory. Moreover, we simulate a supersymmetric theory on the fuzzy sphere, which might provide an alternative to attempted lattice formulations. (orig.)

  20. Nonperturbative studies of quantum field theories on noncommutative spaces

    Energy Technology Data Exchange (ETDEWEB)

    Volkholz, J.

    2007-11-16

    This work deals with three quantum field theories on spaces with noncommuting position operators. Noncommutative models occur in the study of string theories and quantum gravity. They usually elude treatment beyond the perturbative level. Due to the technique of dimensional reduction, however, we are able to investigate these theories nonperturbatively. This entails translating the action functionals into a matrix language, which is suitable for numerical simulations. First we explore the {lambda}{phi}{sup 4} model on a noncommutative plane. We investigate the continuum limit at fixed noncommutativity, which is known as the double scaling limit. Here we focus especially on the fate of the striped phase, a phase peculiar to the noncommutative version of the regularized {lambda}{phi}{sup 4} model. We find no evidence for its existence in the double scaling limit. Next we examine the U(1) gauge theory on a four-dimensional spacetime, where two spatial directions are noncommutative. We examine the phase structure and find a new phase with a spontaneously broken translation symmetry. In addition we demonstrate the existence of a finite double scaling limit which confirms the renormalizability of the theory. Furthermore we investigate the dispersion relation of the photon. In the weak coupling phase our results are consistent with an infrared instability predicted by perturbation theory. If the translational symmetry is broken, however, we find a dispersion relation corresponding to a massless particle. Finally, we investigate a supersymmetric theory on the fuzzy sphere, which features scalar neutral bosons and Majorana fermions. The supersymmetry is exact in the limit of infinitely large matrices. We investigate the phase structure of the model and find three distinct phases. Summarizing, we study noncommutative field theories beyond perturbation theory. Moreover, we simulate a supersymmetric theory on the fuzzy sphere, which might provide an alternative to attempted

  1. Laboratory studies of oil spill bioremediation; toward understanding field behavior

    International Nuclear Information System (INIS)

    Prince, R.C.; Hinton, S.M.; Elmendorf, D.L.; Lute, J.R.; Grossman, M.J.; Robbins, W.K.; Hsu, Chang S.; Richard, B.E.; Haith, C.E.; Senius, J.D.; Minak-Bernero, V.; Chianelli, R.R.; Bragg, J.R.; Douglas, G.S.

    1993-01-01

    Oil spill remediation aims to enhance the natural process of microbial hydrocarbon biodegradation. The microbial foundations have been studied throughout this century, but the focus of most of this work has been on the degradation of well defined compounds by well defined microbial species. This paper addresses laboratory studies on crude oil biodegradation by microbial consortia obtained from oiled beaches in Prince William Sound, Alaska following the spill from the Exxon Valdez. It demonstrates that oil degradation is indeed likely to be nitrogen-limited in Prince William Sound, the different molecular classes in crude oil that are subjected to biodegradation, the identification of conserved species in the oil that can be used for assessing biodegradation and bioremediation in the field, the effectiveness of fertilizers in stimulating sub-surface biodegradation, the role of the olephilic fertilizer Inipol EAP22, and the identification of the oil-degrading microorganisms in Prince William Sound. Together, these laboratory studies provided guidance and important insights into the microbial phenomena underlying the successful bioremediation of the oiled shorelines

  2. Upscaling behavioural studies to the field using acoustic telemetry.

    Science.gov (United States)

    Hellström, Gustav; Klaminder, Jonatan; Jonsson, Micael; Fick, Jerker; Brodin, Tomas

    2016-01-01

    Laboratory-based behavioural assays are often used in ecotoxicological studies to assess the environmental risk of aquatic contaminants. While results from such laboratory-based risk assessments may be difficult to extrapolate to natural environments, technological advancements over the past decade now make it possible to perform risk assessments through detailed studies of exposed individuals in natural settings. Acoustic telemetry is a technology to monitor movement and behaviour of aquatic organism in oceans, lakes, and rivers. The technology allows for tracking of multiple individuals simultaneously with very high temporal and spatial resolution, with the option to incorporate sensors to measure various physiological and environmental parameters. Although frequently used in fisheries research, aquatic ecotoxicology has been slow to adopt acoustic telemetry as a tool in field-based studies. This mini-review intends to introduce acoustic telemetry to aquatic ecotoxicologists, focusing on the potential of the technology to bridge the gap between laboratory assays and natural behaviours when making toxicological risk assessments. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. A Study of Thermocurrent Induced Magnetic Fields in ILC Cavities

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, Anthony C. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Cooley, Victoria [Univ. of Wisconsin, Madison, WI (United States)

    2014-03-31

    The case of axisymmetric ILC-type cavities with titanium helium vessels is investigated. A first-order estimate for magnetic field within the SRF current layer is presented. The induced magnetic field is found to be not more than 1.4x10-8 Tesla = 0.14 milligauss for the case of axial symmetry. Magnetic fields due to symmetry breaking effects are discussed.

  4. A study on environmental pollution control in energy field

    Energy Technology Data Exchange (ETDEWEB)

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

    1995-12-01

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

  5. Numerical Study of Buoyancy Convection of Air under Permanent Magnetic Field and Comparison with That under Gravity Field

    Directory of Open Access Journals (Sweden)

    Kewei Song

    2014-01-01

    Full Text Available Magnetothermal free convection of air in a square enclosure under a nonuniform magnetic field provided by a permanent neodymium-iron-boron magnet is numerically studied. The natural convection under the gravity field alone is also studied for comparison. The physical fields of magnetizing force, velocity, and temperature as well as the local distribution characteristic of Nusselt number are all presented in this paper. The results show that the buoyancy convection of air in the square enclosure under magnetic field is quite different from that under the gravity field. The local value of Nusselt number under the magnetic field supplied by a permanent magnet with a residual magnetic flux density of about 4.5 Tesla can reach a high value of about three times larger than the maximum local value of Nusselt number under the gravity field. Relatively uniform distributions of temperature gradient and Nusselt number can be obtained along the cold wall of the enclosure under the magnetic field. A permanent magnet with high magnetic energy product with Br reaching to 3.5 Tesla can play a comparative role on the averaged Nusselt number compared with that under the gravity environment.

  6. [Magnetic fields evoked by auditory stimuli: a normative study].

    Science.gov (United States)

    Maurizi, M; Corina, L; Del Gratta, C; Galli, J; Paludetti, G; Pasquarelli, A; Pellini, R; Peresson, M; Pizzella, V; Romani, G L

    1992-01-01

    After outlining the fundamentals of biomagnetism and their possible clinical applications, the authors report the results of a normative study on auditory magnetic fields performed on 18 normally hearing subjects between the ages of 25 and 30. Having presented a thorough review of the literature, they then describe the recording technique employed, the dcSQUID biomagnetic system for signal detection, the shielded room, the characteristics of the stimulus. The auditory magnetic response is characterized by three main waves (P4Om, N100m, P200m) whose latency and amplitude values were calculated. Moreover, in order to localize dipolar activity, certain parameters, such as P and T, were taken into consideration. Localizations were made using a spherical volume conductor or with MRI, which was in any case employed in all the subjects. The waves, especially the N100m recorded contralaterally to the stimulus, showed a reduced latency and an increased amplitude when compared to those recorded ipsilaterally. Moreover, a systematic posterior shift of the N100m source into the left hemisphere with respect to the right one was detected. In conclusion, the authors emphasize the need to study electric as well as magnetic responses in order to better understand auditory cortical functions.

  7. Study of Rare Events at the Split Field Magnet

    CERN Multimedia

    2002-01-01

    The aim of the experiment is the study of full events associated with special, rare triggers using the almost 4 @p geometry of the improved Split Field Magnet (SFM) detector. Two triggers are used: a) a trigger on an electron produced around 90|0 with a transverse momentum p^t @$>$ 0.5 GeV/c; b) a trigger on very high p^t hadrons (p^t $>$ 5 GeV/c) at @Q @C 45|0, using the SFM chambers to define roads pointing to the interaction region. In the first case, the associated event will be studied to determine the origin of direct electron production in charmed particle production. In the second case, the production of jets or jet-like objects when a high p^t particle is produced in pp collisions will be investigated. To carry out this program, the detection system consists of : \\item a) An improved SFM detector chamber system and layout to detect more of the produced particles and to simplify the pattern recognition problem in multiparticle events. \\item b) An improved program chain for the analysis of SFM events, ...

  8. Study of electric field pulsation in helical plasmas

    International Nuclear Information System (INIS)

    Toda, S; Itoh, K

    2011-01-01

    A model for the experimental results of the periodic oscillation of the electric field, so-called the electric field pulsation, observed in the Compact Helical Device (Fujisawa et al 1998 Phys. Rev. Lett. 81 2256) and the Large Helical Device (Shimizu et al 2010 Plasma Fusion Res. 5 S1015) is presented. A self-generated oscillation of the radial electric field is shown as the simulation result in helical plasmas. The reduction of the anomalous transport diffusivity in the core region is observed due to the strong shear of the radial electric field when the positive electric field is shown in the core region in the periodic oscillation of E r . Two different time scales are found in the self-generated oscillation, which are the transport time scale and the fast time scale at the transition of the radial electric field. This oscillation because of the hysteresis characteristic is attributed to the electric field pulsation observed in helical plasmas. The parameter region of the condition for the self-generated oscillation is derived. It is shown that the multiple solutions of the radial electric field for the ambipolar condition are necessary but not sufficient for obtaining the self-generated oscillation.

  9. Topological study of magnetic field near a neutral point

    International Nuclear Information System (INIS)

    Fukao, Shoichiro; Ugai, Masayuki; Tsuda, Takao.

    1975-01-01

    Configuration of magnetic fields near a neutral point is re-examined by a topological analysis. The so-called X-and 0-type magnetic fields respectively occupy their own seat in our classified table. Then the existence of the spiral and node types of configuration will be shown by the analysis. (auth.)

  10. Hydraulic fracturing: insights from field, lab, and numerical studies

    Science.gov (United States)

    Walsh, S. D.; Johnson, S.; Fu, P.; Settgast, R. R.

    2011-12-01

    Hydraulic fracturing has become an increasingly important technique in stimulating reservoirs for gas, oil, and geothermal energy production. In use commercially since the 1950's, the technique has been widely lauded, when combined with other techniques, for enabling the development of shale gas resources in the United States, providing a valuable and extensive source of domestic energy. However, the technique has also drawn a degree of notoriety from high-profile incidents involving contamination of drinking water associated with gas extraction operations in the Marcellus shale region. This work highlights some of the insights on the behavior of subsurface hydraulic fracturing operations that have been derived from field and laboratory observations as well as from numerical simulations. The sensitivity of fracture extent and orientation to parameters such as matrix material heterogeneity, presence and distribution of discontinuities, and stress orientation is of particular interest, and we discuss this in the context of knowledge derived from both observation and simulation. The limitations of these studies will also be addressed in terms of resolution, uncertainty, and assumptions as well as the balance of fidelity to cost, both in computation time (for numerical studies) and equipment / operation cost (for observational studies). We also identify a number of current knowledge gaps and propose alternatives for addressing those gaps. We especially focus on the role of numerical studies for elucidating key concepts and system sensitivities. The problem is inherently multi-scale in both space and time as well as highly coupled hydromechanically, and, in several applications, thermally as well. We will summarize the developments to date in analyzing these systems and present an approach for advancing the capabilities of our models in the short- to long-term and how these advances can help provide solutions to reduce risk and improve efficiency of hydraulic fracturing

  11. Molecular modeling studies of structural properties of polyvinyl alcohol: a comparative study using INTERFACE force field.

    Science.gov (United States)

    Radosinski, Lukasz; Labus, Karolina

    2017-10-05

    Polyvinyl alcohol (PVA) is a material with a variety of applications in separation, biotechnology, and biomedicine. Using combined Monte Carlo and molecular dynamics techniques, we present an extensive comparative study of second- and third-generation force fields Universal, COMPASS, COMPASS II, PCFF, and the newly developed INTERFACE, as applied to this system. In particular, we show that an INTERFACE force field provides a possibility of composing a reliable atomistic model to reproduce density change of PVA matrix in a narrow temperature range (298-348 K) and calculate a thermal expansion coefficient with reasonable accuracy. Thus, the INTERFACE force field may be used to predict mechanical properties of the PVA system, being a scaffold for hydrogels, with much greater accuracy than latter approaches. Graphical abstract Molecular Dynamics and Monte Carlo studies indicate that it is possible to predict properties of the PVA in narrow temperature range by using the INTERFACE force field.

  12. Light Scattering Studies of Organic Field Effect Transistors

    Science.gov (United States)

    Adil, Danish

    Organic semiconductors hold a great promise of enabling new technology based on low cost and flexible electronic devices. While much work has been done in the field of organic semiconductors, the field is still quite immature when compared to that of traditional inorganic based devices. More work is required before the full potential of organic field effect transistors (OFETs), organic light emitting diodes (OLEDs), and organic photovoltaics (OPVs) is realized. Among such work, a further development of diagnostic tools that characterize charge transport and device robustness more efficiently is required. Charge transport in organic semiconductors is limited by the nature of the metal-semiconductor interfaces where charge is injected into the semiconductor film and the semiconductor-dielectric interface where the charge is accumulated and transported. This, combined with that fact that organic semiconductors are especially susceptible to having structural defects induced via oxidation, charge transport induced damage, and metallization results in a situation where a semiconductor film's ability to conduct charge can degrade over time. This degradation manifests itself in the electrical device characteristics of organic based electronic devices. OFETs, for example, may display changes in threshold voltage, lowering of charge carrier mobilities, or a decrease in the On/Off ratio. All these effects sum together to result in degradation in device performance. The work begins with a study where matrix assisted pulsed laser deposition (MAPLE), an alternative organic semiconductor thin film deposition method, is used to fabricate OFETs with improved semiconductor-dielectric interfaces. MAPLE allows for the controlled layer-by-layer growth of the semiconductor film. Devices fabricated using this technique are shown to exhibit desirable characteristics that are otherwise only achievable with additional surface treatments. MAPLE is shown to be viable alternative to other

  13. Pulsed Electromagnetic Field Assisted in vitro Electroporation: A Pilot Study

    Science.gov (United States)

    Novickij, Vitalij; Grainys, Audrius; Lastauskienė, Eglė; Kananavičiūtė, Rūta; Pamedytytė, Dovilė; Kalėdienė, Lilija; Novickij, Jurij; Miklavčič, Damijan

    2016-09-01

    Electroporation is a phenomenon occurring due to exposure of cells to Pulsed Electric Fields (PEF) which leads to increase of membrane permeability. Electroporation is used in medicine, biotechnology, and food processing. Recently, as an alternative to electroporation by PEF, Pulsed ElectroMagnetic Fields (PEMF) application causing similar biological effects was suggested. Since induced electric field in PEMF however is 2-3 magnitudes lower than in PEF electroporation, the membrane permeabilization mechanism remains hypothetical. We have designed pilot experiments where Saccharomyces cerevisiae and Candida lusitaniae cells were subjected to single 100-250 μs electrical pulse of 800 V with and without concomitant delivery of magnetic pulse (3, 6 and 9 T). As expected, after the PEF pulses only the number of Propidium Iodide (PI) fluorescent cells has increased, indicative of membrane permeabilization. We further show that single sub-millisecond magnetic field pulse did not cause detectable poration of yeast. Concomitant exposure of cells to pulsed electric (PEF) and magnetic field (PMF) however resulted in the increased number PI fluorescent cells and reduced viability. Our results show increased membrane permeability by PEF when combined with magnetic field pulse, which can explain electroporation at considerably lower electric field strengths induced by PEMF compared to classical electroporation.

  14. Field study - Steinle Ranch, an intermediate depth oil field, shows significant benefit from bauxite proppants

    Energy Technology Data Exchange (ETDEWEB)

    Kohlhaas, C.A.

    1982-01-01

    The Steinle Ranch field initially was developed in the mid-1970s. Wells were drilled, cased, perforated, and treated by chemical injection with lease-crude or condensate carriers to restore oil saturation to the formation, which is suspected to be hydrophobic. Stimulation by hydraulic fracturing of 4 wells was attempted from 1975 through 1977 with mixed results and no particular success. These treatments used sand and glass beads for proppant. A fifth hydraulic fracture treatment, in which sintered bauxite was used as the proppant was very successful. As a result, all wells in the field have been fractured. This program, in a mature field in late stages of depletion, at intermediate depth (10,600 ft), has been very successful; ca 940,000 bbl of additional reserves have resulted for a total cost of ca $2,000,000, a return on investment of 9.4:1. Comparing these reserves to estimated reserves if the wells had been propped with sand shows a 23:1 return by the incremental reserves on the incremental cost of the bauxite.

  15. Transport studies in high-performance field reversed configuration plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, S., E-mail: sgupta@trialphaenergy.com; Barnes, D. C.; Dettrick, S. A.; Trask, E.; Tuszewski, M.; Deng, B. H.; Gota, H.; Gupta, D.; Hubbard, K.; Korepanov, S.; Thompson, M. C.; Zhai, K.; Tajima, T. [Tri Alpha Energy, Inc., P.O. Box 7010, Rancho Santa Margarita, California 92688 (United States)

    2016-05-15

    A significant improvement of field reversed configuration (FRC) lifetime and plasma confinement times in the C-2 plasma, called High Performance FRC regime, has been observed with neutral beam injection (NBI), improved edge stability, and better wall conditioning [Binderbauer et al., Phys. Plasmas 22, 056110 (2015)]. A Quasi-1D (Q1D) fluid transport code has been developed and employed to carry out transport analysis of such C-2 plasma conditions. The Q1D code is coupled to a Monte-Carlo code to incorporate the effect of fast ions, due to NBI, on the background FRC plasma. Numerically, the Q1D transport behavior with enhanced transport coefficients (but with otherwise classical parametric dependencies) such as 5 times classical resistive diffusion, classical thermal ion conductivity, 20 times classical electron thermal conductivity, and classical fast ion behavior fit with the experimentally measured time evolution of the excluded flux radius, line-integrated density, and electron/ion temperature. The numerical study shows near sustainment of poloidal flux for nearly 1 ms in the presence of NBI.

  16. An experimental field study of weight salience and food choice.

    Science.gov (United States)

    Incollingo Rodriguez, Angela C; Finch, Laura E; Buss, Julia; Guardino, Christine M; Tomiyama, A Janet

    2015-06-01

    Laboratory research has found that individuals will consume more calories and make unhealthy food choices when in the presence of an overweight individual, sometimes even regardless of what that individual is eating. This study expanded these laboratory paradigms to the field to examine how weight salience influences eating in the real world. More specifically, we tested the threshold of the effect of weight salience of food choice to see if a more subtle weight cue (e.g., images) would be sufficient to affect food choice. Attendees (N = 262) at Obesity Week 2013, a weight-salient environment, viewed slideshows containing an image of an overweight individual, an image of a thin individual, or no image (text only), and then selected from complimentary snacks. Results of ordinal logistic regression analysis showed that participants who viewed the image of the overweight individual had higher odds of selecting the higher calorie snack compared to those who viewed the image of the thin individual (OR = 1.77, 95% CI = [1.04, 3.04]), or no image (OR = 2.42, 95% CI = [1.29, 4.54]). Perceiver BMI category did not moderate the influence of image on food choice, as these results occurred regardless of participant BMI. These findings suggest that in the context of societal weight salience, weight-related cues alone may promote unhealthy eating in the general public. Published by Elsevier Ltd.

  17. Serum Dried Samples to Detect Dengue Antibodies: A Field Study

    Science.gov (United States)

    Maldonado-Rodríguez, Angelica; Rojas-Montes, Othon; Chavez-Negrete, Adolfo; Rojas-Uribe, Magdalena; Posadas-Mondragon, Araceli; Aguilar-Faisal, Leopoldo; Xoconostle-Cazares, Beatriz

    2017-01-01

    Background Dried blood and serum samples are useful resources for detecting antiviral antibodies. The conditions for elution of the sample need to be optimized for each disease. Dengue is a widespread disease in Mexico which requires continuous surveillance. In this study, we standardized and validated a protocol for the specific detection of dengue antibodies from dried serum spots (DSSs). Methods Paired serum and DSS samples from 66 suspected cases of dengue were collected in a clinic in Veracruz, Mexico. Samples were sent to our laboratory, where the conditions for optimal elution of DSSs were established. The presence of anti-dengue antibodies was determined in the paired samples. Results DSS elution conditions were standardized as follows: 1 h at 4°C in 200 µl of DNase-, RNase-, and protease-free PBS (1x). The optimal volume of DSS eluate to be used in the IgG assay was 40 µl. Sensitivity of 94%, specificity of 93.3%, and kappa concordance of 0.87 were obtained when comparing the antidengue reactivity between DSSs and serum samples. Conclusion DSS samples are useful for detecting anti-dengue IgG antibodies in the field. PMID:28630868

  18. Field Studies of Geothermal Reservoirs Rio Grande Rift, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    James C Witcher

    2002-07-30

    The Rio Grande rift provides an excellent field laboratory to study the nature of geothermal systems in an extensional environment. Much of the geologic complexity that is found in the Basin and Range is absent because the rift is located on cratonic crust with a thin and well-characterized Phanerozoic stratigraphy and tectonic history. On the other hand, the Neogene thermo-tectonic history of the rift has many parallels with the Basin and Range to the west. The geology of the southern Rio Grande rift is among the best characterized of any rift system in the world. Also, most geologic maps for the region are rather unique in that detailed analyses of Quaternary stratigraphic and surficial unit are added in concert with the details of bedrock geology. Pleistocene to Holocene entrenchment of the Rio Grande and tributaries unroofs the alteration signatures and permeability attributes of paleo outflow plumes and upflow zones, associated with present-day, but hidden or ''blind,'' hydrothermal systems at Rincon and San Diego Mountain.

  19. Plasma-induced field emission study of carbon nanotube cathode

    Directory of Open Access Journals (Sweden)

    Yi Shen

    2011-10-01

    Full Text Available An investigation on the plasma-induced field emission (PFE properties of a large area carbon nanotube (CNT cathode on a 2 MeV linear induction accelerator injector is presented. Experimental results show that the cathode is able to emit intense electron beams. Intense electron beams of 14.9–127.8  A/cm^{2} are obtained from the cathode. The CNT cathode desorbs gases from the CNTs during the PFE process. The fast cathode plasma expansion affects the diode perveance. The amount of outgassing is estimated to be 0.06–0.49  Pa·L, and the ratio of outgassing and electron are roughly calculated to be within the range of 170–350 atoms per electron. The effect of the outgassing is analyzed, and the outgassing mass spectrum of the CNT cathode has been studied during the PFE. There is a significant desorption of CO_{2}, N_{2}(CO, and H_{2} gases, which plays an important role during the PFE process. All the experiments demonstrate that the outgassing plays an important role in the formation of the cathode plasma. Moreover, the characteristic turn-on time of the CNT cathode was measured to be 39 ns.

  20. Entanglement negativity and conformal field theory: a Monte Carlo study

    International Nuclear Information System (INIS)

    Alba, Vincenzo

    2013-01-01

    We investigate the behavior of the moments of the partially transposed reduced density matrix ρ A T 2 in critical quantum spin chains. Given subsystem A as the union of two blocks, this is the (matrix) transpose of ρ A with respect to the degrees of freedom of one of the two blocks. This is also the main ingredient for constructing the logarithmic negativity. We provide a new numerical scheme for efficiently calculating all the moments of ρ A T 2 using classical Monte Carlo simulations. In particular we study several combinations of the moments which are scale invariant at a critical point. Their behavior is fully characterized in both the critical Ising and the anisotropic Heisenberg XXZ chains. For two adjacent blocks we find, in both models, full agreement with recent conformal field theory (CFT) calculations. For disjoint blocks, in the Ising chain finite size corrections are nonnegligible. We demonstrate that their exponent is the same as that governing the unusual scaling corrections of the mutual information between the two blocks. Monte Carlo data fully match the theoretical CFT prediction only in the asymptotic limit of infinite intervals. Oppositely, in the Heisenberg chain scaling corrections are smaller and, already at finite (moderately large) block sizes, Monte Carlo data are in excellent agreement with the asymptotic CFT result. (paper)

  1. Serum Dried Samples to Detect Dengue Antibodies: A Field Study

    Directory of Open Access Journals (Sweden)

    Angelica Maldonado-Rodríguez

    2017-01-01

    Full Text Available Background. Dried blood and serum samples are useful resources for detecting antiviral antibodies. The conditions for elution of the sample need to be optimized for each disease. Dengue is a widespread disease in Mexico which requires continuous surveillance. In this study, we standardized and validated a protocol for the specific detection of dengue antibodies from dried serum spots (DSSs. Methods. Paired serum and DSS samples from 66 suspected cases of dengue were collected in a clinic in Veracruz, Mexico. Samples were sent to our laboratory, where the conditions for optimal elution of DSSs were established. The presence of anti-dengue antibodies was determined in the paired samples. Results. DSS elution conditions were standardized as follows: 1 h at 4°C in 200 µl of DNase-, RNase-, and protease-free PBS (1x. The optimal volume of DSS eluate to be used in the IgG assay was 40 µl. Sensitivity of 94%, specificity of 93.3%, and kappa concordance of 0.87 were obtained when comparing the antidengue reactivity between DSSs and serum samples. Conclusion. DSS samples are useful for detecting anti-dengue IgG antibodies in the field.

  2. The study of informational professional field of pharmacy specialists

    Directory of Open Access Journals (Sweden)

    N. O. Tkachenko

    2014-08-01

    Full Text Available Today professionalism is important not only for the characteristics of an individual, but also for the manifestation of professional activities. Self-education, self-training and training on the working place are integral elements of the whole continuous professional development. Various components of professionalism form the social responsibility of pharmacist in contemporary conditions. During all professional activities of pharmacists the continuous formation of administrative, economic, legal, communication, social and information competence takes place. Professionally oriented periodical publications, scientific and practical activities act as assistants in it. The aim of this work was to study the sources of the information professional field of pharmaceutical establishments’ staff in the South-eastern region of Ukraine and to determine the frequency of their use and orientation. Gathering of information was carried out using questionnaires. The structure of the developed questionnaire provided conventional separation of questions into two blocks. The first set of questions in the questionnaire provided respondents’ characteristics by demographic and psychological criteria: age, position, length of service, type of enterprise’s ownership. The second set of questions provided the opportunity to identify the main sources of professional information of the specialists in the region, the frequency of their use and the orientation of information for practical activities. Results and discussion. The respondents were proposed the list of periodicals, which today pharmacy specialists are guided by for understanding of modern trends in medicine and pharmacy. The survey results made it possible to determine the most required in practice, sources of information on modern medicine and pharmacy: special edition "Mister blister", "Weekly Drugstore" and "Pharmacist Practical worker". Experts of various levels of pharmacy management use these

  3. Petrophysical Study of Szolnok Formation, Endrod Gas Field, Hungary

    Science.gov (United States)

    El Sayed, Abdel Moktader A.; El Sayed, Nahla A.

    2017-12-01

    Investigation of rock porosity and permeability is highly beneficial for geologists, petro-physicist and petroleum engineers in order to evaluate reservoir pore space geometry through the time and space. Clastic reservoir quality and classification could perform based on the petrophysical data correlations. Study of the Szolnok formation was our target. It is composed mainly of sandstones with clay-marlstone and siltstones. Two hundred thirteen-core samples of Upper and Lower Pliocene and Miocene age were subjected for petrophysical investigations. Pore size distribution using MICP, Mercury and Helium porosity, horizontal and vertical permeability were measured for studied core samples. The Szolnok Formation has two main lithologic facies: a. 141 clean sandstone samples and b. 72 siltstone and clay-marlstone samples. Ultrasonic laboratory measurements were carried out for only 30 selected sandstone core samples. Sonic viewer-120 is used to measure sonic velocities and other mechanical properties such as rigidity, bulk modulus and Young’s modulus. Gas permeability and Helium porosity were plotted versus sonic wave velocity indicates that both permeability and porosity could be outlined from either compressional or shear wave velocity. Effective pore radius is outlined from both of them. The highest sample porosity was recorded for the Miocene in age followed by the Lower Pliocene and then for the Upper Pliocene samples respectively. Miocene samples are relatively clayey free followed by Lower Pliocene samples because they have higher sonic velocity (Vp and Vs) than the Upper Pliocene samples. The Miocene and Lower Pliocene samples have relatively lower dynamic mechanical parameters than Upper Pliocene samples which represent good gas reservoirs in the Endrod field. Several regression line equations with high coefficient of correlation have been calculated to predict Szolnok reservoir parameters.

  4. Coordinated Airborne Studies in the Tropics (CAST) Field Campaign Report

    Energy Technology Data Exchange (ETDEWEB)

    Vaughan, Geraint [Univ. of Manchester (United Kingdom)

    2016-05-01

    The last field campaign held at the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility site on Manus Island, Papua New Guinea (PNG), was conducted in February 2014 as part of the Co-ordinated Airborne Studies in the Tropics (CAST) campaign. This campaign was a collaboration between the National Aeronautics and Space Administration (NASA), National Center for Atmospheric Research (NCAR), and the United Kingdom’s (UK) Natural Environment Research Council (NERC) to study the composition of the Tropical Tropopause Layer (TTL) and the impact of deep convection on this composition. There are three main areas of interest: i) transport of trace gases in the tropical atmosphere (especially short-lived halogenated compounds that can be lifted rapidly into the TTL, where they augment the stratospheric loading of these species); ii) formation of cirrus and its impact on the TTL; and iii) the upper-atmosphere water vapor budget. Overall, the aim was to improve understanding of the dynamical, radiative, and chemical role of the TTL. The Manus operation was a joint experiment between the Universities of Manchester and Cambridge and the UK National Centre for Atmospheric Science (NCAS). It consisted of two elements: an ozonesonde campaign to measure ozone vertical profiles through the TTL, and ground-based monitoring of ozone, halogenated hydrocarbons, and greenhouse gases to determine the composition of lower-boundary-layer air in the Warm Pool region. Thanks to the support from the ARM Climate Research Facility and the exemplary collaboration of ARM staff in the region, the campaign was very successful.

  5. The TITAN Reversed-Field Pinch fusion reactor study

    International Nuclear Information System (INIS)

    1988-03-01

    The TITAN Reversed-Field Pinch (RFP) fusion reactor study is a multi-institutional research effort to determine the technical feasibility and key developmental issues of an RFP fusion reactor, especially at high power density, and to determine the potential economics, operations, safety, and environmental features of high-mass-power-density fusion systems. The TITAN conceptual designs are DT burning, 1000 MWe power reactors based on the RFP confinement concept. The designs are compact, have a high neutron wall loading of 18 MW/m 2 and a mass power density of 700 kWe/tonne. The inherent characteristics of the RFP confinement concept make fusion reactors with such a high mass power density possible. Two different detailed designs have emerged: the TITAN-I lithium-vanadium design, incorporating the integrated-blanket-coil concept; and the TITAN-II aqueous loop-in-pool design with ferritic steel structure. This report contains a collection of 16 papers on the results of the TITAN study which were presented at the International Symposium on Fusion Nuclear Technology. This collection describes the TITAN research effort, and specifically the TITAN-I and TITAN-II designs, summarizing the major results, the key technical issues, and the central conclusions and recommendations. Overall, the basic conclusions are that high-mass power-density fusion reactors appear to be technically feasible even with neutron wall loadings up to 20 MW/m 2 ; that single-piece maintenance of the FPC is possible and advantageous; that the economics of the reactor is enhanced by its compactness; and the safety and environmental features need not to be sacrificed in high-power-density designs. The fact that two design approaches have emerged, and others may also be possible, in some sense indicates the robustness of the general findings

  6. Alabama warm mix asphalt field study : final report.

    Science.gov (United States)

    2010-05-01

    The Alabama Department of Transportation hosted a warm mix asphalt field demonstration in August 2007. The warm mix asphalt technology demonstrated was Evotherm Dispersed Asphalt Technology. The WMA and hot mix asphalt produced for the demonstration ...

  7. Studies on thermal fields in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Gopalakrishna, V.V.; Rao, A.S.

    Chennai-Andamans section collected using ships of opportunity during 1991-96, spatio temporal variability of upper layer thermal fields is examined on annual and interannual time scales. The observed variability is supported with two independent data sets...

  8. The study on electromagnetic field of an RFQ

    CERN Document Server

    Ouyang Hua Fu; Luo Zi Hua; Xu Tao Guang; Xu Wen Wu

    2002-01-01

    Computer simulations are carried out for calculating the electromagnetic field distribution and frequency in either 2-D coordinates (by SUPERFISH) or 3-D coordinates (by MAFIA), by which the tuners, the end cells, the coupling cells and other components of the radio-frequency quadrupole (RFQ) are designed. The designing principle is that the E-field longitudinal distribution and the local quadrupole cut-off frequency should be kept as constant as possible

  9. Enhanced Soundings for Local Coupling Studies Field Campaign Report

    Energy Technology Data Exchange (ETDEWEB)

    Ferguson, Craig R [University at Albany, State University of New York; Santanello, Joseph A [NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States); Gentine, Pierre [Columbia Univ., New York, NY (United States)

    2016-04-01

    This document presents initial analyses of the enhanced radiosonde observations obtained during the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility Enhanced Soundings for Local Coupling Studies Field Campaign (ESLCS), which took place at the ARM Southern Great Plains (SGP) Central Facility (CF) from June 15 to August 31, 2015. During ESLCS, routine 4-times-daily radiosonde measurements at the ARM-SGP CF were augmented on 12 days (June 18 and 29; July 11, 14, 19, and 26; August 15, 16, 21, 25, 26, and 27) with daytime 1-hourly radiosondes and 10-minute ‘trailer’ radiosondes every 3 hours. These 12 intensive operational period (IOP) days were selected on the basis of prior-day qualitative forecasts of potential land-atmosphere coupling strength. The campaign captured 2 dry soil convection advantage days (June 29 and July 14) and 10 atmospherically controlled days. Other noteworthy IOP events include: 2 soil dry-down sequences (July 11-14-19 and August 21-25-26), a 2-day clear-sky case (August 15-16), and the passing of Tropical Storm Bill (June 18). To date, the ESLCS data set constitutes the highest-temporal-resolution sampling of the evolution of the daytime planetary boundary layer (PBL) using radiosondes at the ARM-SGP. The data set is expected to contribute to: 1) improved understanding and modeling of the diurnal evolution of the PBL, particularly with regard to the role of local soil wetness, and (2) new insights into the appropriateness of current ARM-SGP CF thermodynamic sampling strategies.

  10. Field study of nanoparticles by small angle neutron scattering

    International Nuclear Information System (INIS)

    Mirebeau, I.; Hennion, M.; Bellouard, C.

    1994-01-01

    In nanometric iron particles, magnetic correlations are determined by small angle neutron scattering and compared to their values calculated in a simple superparamagnetic model. The introduction of a Lorentzian shape for the magnetic form factor is necessary to obtain a good fit of the data. This reveals two extra features: a spin disorder at the surface of the particles which persists in applied field, and a distribution in the particle sizes not probed by X-rays. The field alignment becomes easier with decreasing temperature. This is no longer true for samples with bigger and closer-packed particles, where strong dipolar interactions develop at low temperatures and oppose to the external field. 4 figs., 3 refs

  11. Field Engineers' Scheduling at Oil Rigs: a Case Study

    Directory of Open Access Journals (Sweden)

    Y. S. Usmani

    2012-02-01

    Full Text Available Oil exploration and production operations face a number of challenges. Professional planners have to design solutions for various practical problems or issues. However, the time consumed is often very extensive because of the large number of possible solutions. Further, the matter of choosing the best solution remains. The present paper investigates a problem related to leading companies in the energy and chemical manufacturing sector of the oil and gas industry. Each company’s field engineers are expensive and valuable assets. Therefore, an optimized roster is rather important. In the present paper, the objective is to design a field engineers’ schedule which would be both feasible and satisfying towards the various demands of rigs, with minimum operational cost to the company. An efficient and quick optimization technique is presented to schedule the shifts of field engineers.

  12. Experimental study on the luminous radiation associated to the field emission of samples submitted to high RF fields

    International Nuclear Information System (INIS)

    Maissa, S.; Junquera, T.; Fouaidy, M.; Le Goff, A.; Luong, M.; Tan, J.; Bonin, B.; Safa, H.

    1996-01-01

    The accelerating gradient of the RF cavities is limited by the strong field emission (FE) of electrons stemming from the metallic walls. Previous experiments evidenced luminous radiations associated with electron emission of cathodes subjected to intense DC electric field. These observations invoked the proposal of new theoretical models of the field emission phenomenon. This experimental study extends the previous DC works to the RF case. A special copper RF cavity has been developed equipped with an optical window and a removable sample. It has been designed for measuring both electron current and luminous radiation emitted by the sample, subjected to maximum RF electric field. The optical apparatus attached to the cavity permits to characterize the radiation in terms of intensity, glowing duration and spectral distribution. The results concerning different niobium or copper samples, whom top was either scratched or intentionally contaminated with metallic or dielectric particles are summarized. (author)

  13. A field study of "lambda distribution" for breaking wave crests

    Science.gov (United States)

    Dulov, V.; Mironov, A.

    2009-04-01

    "Lambda distribution" concept introduced by Phillips (1985) provides a way to link wind wave spectra and numerous important measures of the air-sea interface processes related to wave breaking. Production of sea drops in the near water atmospheric layer (Kudryavtsev, 2006), radar backscattering due to wave breaking (Phillips, 1988, Kudryavtsev et al., 2003), turbulent mixing in the uppermost sea layer (Kudryavtsev et al., 2008) and other phenomena were recently studied on the basis of this approach. In this connection experimental investigations of the key theoretical quantity, Λ(c)dc, the average length of breaking crests per unit area propagating with speeds in the range (c, c + dc), and its dependence on wave spectra are of obvious importance. An experimental study of Λ(c) was performed during three field campaigns (2003, 2005 and 2008) on the Black Sea research platform of Marine Hydrophysical Institute (National Academy of Sciences of Ukraine). Simultaneous recordings of wave breaking measures (with video camera) and wave 2D-spectra (with an array of resistance wave staffs) were obtained under variety of wave conditions at wind speed 4-20m/s. A special method was developed to evaluate geometrical and kinematical whitecap parameters including their vectors of advance velocity. Individual whitecaps corresponding to active phase of wave breaking (phase A) were extracted from video recordings of the sea surface practically without human influence on the process of data processing because the method is based on physical considerations of sea surface brightness and empirical information on whitecap dynamics. Estimations of Λ(c) were derived from data obtained. Spectral energy dissipation rates were evaluated from the wave spectra and from the Λ(c) in accordance with Phillips approach (1985). Their comparison for every experimental run exhibits poor agreement, but a good agreement was found for integral dissipation rates for all data. Value of Phillips theory

  14. Field Theory in Cultural Capital Studies of Educational Attainment

    DEFF Research Database (Denmark)

    Munk, Martin D.; Krarup, Troels Magelund

    2012-01-01

    This article argues that there is a double recession in international mainstream research in cultural capital and educational attainment: an empirical recession, since few new insights have been gained within recent years, and a theoretical recession, since cultural capital is now seen as a simple...... hypothesis about certain individual resources, disregarding the structural vision and important related concepts such as field, habitus, and strategy in Bourdieu’s sociology. This article reintroduces field theory into cultural capital research in education, taking into consideration current concerns...... in mainstream international quantitative research. It ends with some remarks on the consequences of this change in perspective....

  15. Study of aerosol behaviour in an acoustic field

    International Nuclear Information System (INIS)

    Malherbe, C.

    1988-01-01

    The average size of an aerosol submitted to acoustic waves is increased. This results from coagulation of the finer particles on the larger ones. An experimental apparatus was developed in order to control the evolution of aerosol distribution in an acoustic field. Important deposition on the walls of the agglomeration chamber was observed as a consequence of the acoustically induced turbulent flow. Consequently, we experimentally evaluated the turbulent properties of the system. A granular bed submitted to an acoustic field and set downstream an agglomerator constitutes an almost absolute filter for an usually penetrating aerosol [fr

  16. Study of HTS Wires at High Magnetic Fields

    Energy Technology Data Exchange (ETDEWEB)

    Turrioni, D.; Barzi, E.; Lamm, M.J.; Yamada, R.; Zlobin, A.V.; Kikuchi, A.; /Fermilab

    2009-01-01

    Fermilab is working on the development of high field magnet systems for ionization cooling of muon beams. The use of high temperature superconducting (HTS) materials is being considered for these magnets using Helium refrigeration. Critical current (I{sub c}) measurements of HTS conductors were performed at FNAL and at NIMS up to 28 T under magnetic fields at zero to 90 degree with respect to the sample face. A description of the test setups and results on a BSCCO-2223 tape and second generation (2G) coated conductors are presented.

  17. Design study of CEPC Alternating Magnetic Field Booster

    CERN Document Server

    Bian, T; Cai, Y; Cui, X; Gao, J; Koratzinos, M; Su, F; Wang, D; Wang, Y; Xiao, M; Zhang, C

    2017-01-01

    The CEPC is a next generation circular e+e- collider proposed by China. The design of the full energy booster ring of the CEPC is especially challenging. The ejected beam energy is 120 GeV, but that of the injected beam is only 6 GeV. In a conventional approach, the low magnetic field of the main dipole magnets creates problems. We propose operating the booster ring as a large wiggler at low beam energies and as a normal ring at high energies to avoid the problem of very low dipole magnet fields.

  18. Field and Laboratory Studies of Atmospheric Organic Aerosol

    Science.gov (United States)

    Coggon, Matthew Mitchell

    This thesis is the culmination of field and laboratory studies aimed at assessing processes that affect the composition and distribution of atmospheric organic aerosol. An emphasis is placed on measurements conducted using compact and high-resolution Aerodyne Aerosol Mass Spectrometers (AMS). The first three chapters summarize results from aircraft campaigns designed to evaluate anthropogenic and biogenic impacts on marine aerosol and clouds off the coast of California. Subsequent chapters describe laboratory studies intended to evaluate gas and particle-phase mechanisms of organic aerosol oxidation. The 2013 Nucleation in California Experiment (NiCE) was a campaign designed to study environments impacted by nucleated and/or freshly formed aerosol particles. Terrestrial biogenic aerosol with > 85% organic mass was observed to reside in the free troposphere above marine stratocumulus. This biogenic organic aerosol (BOA) originated from the Northwestern United States and was transported to the marine atmosphere during periodic cloud-clearing events. Spectra recorded by a cloud condensation nuclei counter demonstrated that BOA is CCN active. BOA enhancements at latitudes north of San Francisco, CA coincided with enhanced cloud water concentrations of organic species such as acetate and formate. Airborne measurements conducted during the 2011 Eastern Pacific Emitted Aerosol Cloud Experiment (E-PEACE) were aimed at evaluating the contribution of ship emissions to the properties of marine aerosol and clouds off the coast of central California. In one study, analysis of organic aerosol mass spectra during periods of enhanced shipping activity yielded unique tracers indicative of cloud-processed ship emissions (m/z 42 and 99). The variation of their organic fraction (f42 and f 99) was found to coincide with periods of heavy (f 42 > 0.15; f99 > 0.04), moderate (0.05 ammonium sulfate seed was coated with a layer of secondary organic aerosol (SOA) from toluene oxidation

  19. Application of integrated petroleum reservoir study for intervention and field development program in western onshore field, India

    Directory of Open Access Journals (Sweden)

    Vijai Kumar Baskaran

    2017-12-01

    Full Text Available In this research, an integrated reservoir study is performed in the J#Field (J-Oil Field of western onshore, India to evaluate its additional reserves expectations and implement field developments plan using waterflood pilot program. The target strata includes two formations of Paleogene, which is about 3600 ft, namely G#Fm (G-Formation of the Eocene and T#Fm (T-Formation of Oligocene, subdivided into 11 zones. Based on these results, an attempt was made to construct of an optimization plan to exploit it, taking into account that the field is producing since 1947, with a cumulative production of 183.5 MMbbl and an overall recovery factor of 28% until January 2016. On the basis of the potential evaluation and geological modeling, blocks J48 and J45 were simulated, and the remaining oil distribution characteristics in two blocks were studied after history match. The work includes the stratigraphic studies, seismic study, logging interpretation, sedimentary facies modeling, three dimensional geological modeling, simulations for waterflooding, and future field development plans.

  20. Classroom to Community: Field Studies for Exercise Science Students

    Science.gov (United States)

    Melton, Deana; Dail, Teresa K.

    2017-01-01

    The field of kinesiology has seen growth in terms of the number of highly specialized subdisciplines, such as exercise physiology, motor learning, biomechanics, sport and exercise psychology, and fitness management. While some undergraduate students may be comfortable with a chosen concentration, others may enter the kinesiology curriculum lacking…

  1. Field Studies: Hands-on, Real-Science Research.

    Science.gov (United States)

    Cunniff, Patricia A.; McMillen, Janet L.

    1996-01-01

    Describes an intensive three-week experience for 10th and 11th graders in a National Science Foundation Young Scholars Program. Two weeks of biology instruction precede one week of field research. The curriculum includes life histories of birds in the Chesapeake Bay area, reproductive ecology, aquatic ecology, entomology, and statistics. (DDR)

  2. Sampling atmospheric pesticides with SPME: Laboratory developments and field study

    Energy Technology Data Exchange (ETDEWEB)

    Wang Junxia [EPCA-Institut des Sciences Moleculaires, UMR 5255 CNRS-Universite Bordeaux 1, ISM, Site universitaire, 24019 Perigueux Cedex (France); Tuduri, Ludovic [EPCA-Institut des Sciences Moleculaires, UMR 5255 CNRS-Universite Bordeaux 1, ISM, Site universitaire, 24019 Perigueux Cedex (France)], E-mail: l.tuduri@ism.u-bordeaux1.fr; Mercury, Maud [EPCA-Institut des Sciences Moleculaires, UMR 5255 CNRS-Universite Bordeaux 1, ISM, Site universitaire, 24019 Perigueux Cedex (France); Universites d' Aix-Marseille I, II et III-CNRS UMR 6264: Laboratoire Chimie Provence, Equipe Instrumentation et Reactivite Atmospherique (IRA), Universite de Provence Centre de Saint Jerome, Avenue Escadrille Normandie Niemen, 13397 Marseille Cedex 20 (France); Millet, Maurice [Centre de Geochimie de la Surface UMR 7517 CNRS-Universite Louis Pasteur (ULP), LPCA, 1 rue Blessig, 67084 Strasbourg Cedex (France); Briand, Olivier [AFSSET, 253 avenue du General Leclerc, 94701 Maisons-Alfort Cedex (France); Montury, Michel [EPCA-Institut des Sciences Moleculaires, UMR 5255 CNRS-Universite Bordeaux 1, ISM, Site universitaire, 24019 Perigueux Cedex (France)

    2009-02-15

    To estimate the atmospheric exposure of the greenhouse workers to pesticides, solid phase microextraction (SPME) was used under non-equilibrium conditions. Using Fick's law of diffusion, the concentrations of pesticides in the greenhouse can be calculated using pre-determined sampling rates (SRs). Thus the sampling rates (SRs) of two modes of SPME in the lab and in the field were determined and compared. The SRs for six pesticides in the lab were 20.4-48.3 mL min{sup -1} for the exposed fiber and 0.166-0.929 mL min{sup -1} for the retracted fiber. In field sampling, two pesticides, dichlorvos and cyprodinil were detected with exposed SPME. SR with exposed SPME for dichlorvos in the field (32.4 mL min{sup -1}) was consistent with that in the lab (34.5 mL min{sup -1}). SR for dichlorvos in the field (32.4 mL min{sup -1}) was consistent with that in the lab (34.5 mL min{sup -1}). The trends of temporal concentration and the inhalation exposure were also obtained. - SPME was proved to be a powerful and simple tool for determining pesticides' atmospheric concentration.

  3. Evaporation studies on Themeda triandra under field conditions: a ...

    African Journals Online (AJOL)

    In the semi-arid regions of South Africa, the efficiency of water use by natural grazing plants is important and can be used to evaluate the production potentially of comparative grasses. Hydraulic non-floating lysimeters were designed and tested under field conditions and indicated that with accurate calibration for ...

  4. Numerical studies of pair creation in counterpropagating laser fields

    Energy Technology Data Exchange (ETDEWEB)

    Ruf, Matthias

    2009-05-27

    Pair creation from vacuum induced by electromagnetic fields is probably one of the most intriguing phenomena in physics. If the fields are sufficiently strong, the QED vacuum become unstable. Due to the remarkable progress in laser technology during recent years an experimental investigation of pair creation by pure laser light is coming into reach. The focus of this thesis is on pair creation in counterpropagating laser beams. The pair creation probability is calculated employing the numerically obtained solutions of the Dirac equation. This numerical ansatz has the capability of calculating the momentum distribution of the created pairs in a single propagation, for pure time dependent field configurations. Furthermore, it allows to take the magnetic component of the laser fields into account, which is usually neglected. The latter strongly affects the creation process at high laser frequency. The involved numerical calculations are rather time consuming, therefore the second project of this thesis was to develop a highly efficient code for solving relativistic quantum mechanical problems. This is accomplished by adopting the split-operator method to the Klein-Gordon equation. Here the possibility arises to use parallel computing. However the corresponding spin-statistics becomes crucial in the case of pair creation, demonstrated in several examples. (orig.)

  5. Research into induced seismicity in the Groningen field : Further studies

    NARCIS (Netherlands)

    Jansen, J.D.; Herber, Rien

    2017-01-01

    Further research into seismicity caused by natural gas production from the Groningen field is necessary to improve the assessment of seismic risk and develop means to control and reduce it. Research into subsurface aspects is primarily of relevance to assess the seismic hazard component in the

  6. Sampling atmospheric pesticides with SPME: Laboratory developments and field study

    International Nuclear Information System (INIS)

    Wang Junxia; Tuduri, Ludovic; Mercury, Maud; Millet, Maurice; Briand, Olivier; Montury, Michel

    2009-01-01

    To estimate the atmospheric exposure of the greenhouse workers to pesticides, solid phase microextraction (SPME) was used under non-equilibrium conditions. Using Fick's law of diffusion, the concentrations of pesticides in the greenhouse can be calculated using pre-determined sampling rates (SRs). Thus the sampling rates (SRs) of two modes of SPME in the lab and in the field were determined and compared. The SRs for six pesticides in the lab were 20.4-48.3 mL min -1 for the exposed fiber and 0.166-0.929 mL min -1 for the retracted fiber. In field sampling, two pesticides, dichlorvos and cyprodinil were detected with exposed SPME. SR with exposed SPME for dichlorvos in the field (32.4 mL min -1 ) was consistent with that in the lab (34.5 mL min -1 ). SR for dichlorvos in the field (32.4 mL min -1 ) was consistent with that in the lab (34.5 mL min -1 ). The trends of temporal concentration and the inhalation exposure were also obtained. - SPME was proved to be a powerful and simple tool for determining pesticides' atmospheric concentration

  7. Anger Framed : A Field Study on Emotion, Pleasure, and Art

    NARCIS (Netherlands)

    Wagner, Valentin; Klein, Julian; Hanich, Julian; Shah, Mira; Menninghaus, Winfried; Jacobsen, Thomas

    2015-01-01

    We investigated cognitive “art schema” effects—as resulting from framing a situation as one of art reception—on the enjoyability of negative emotions by means of an elaborate disguised anger induction in the field. Because situations of both art reception and participation in lab experiments are

  8. An ontological study of quantum fields and their symmetries

    Science.gov (United States)

    Baker, David John

    This dissertation interprets the formalism of quantum field theory (QFT) to help determine which physical properties are fundamental in worlds with natural laws like ours. I begin by arguing briefly that good metaphysical evidence can be drawn from mathematically rigorous forms of QFT. Although these rigorous QFTs are presently limited in their domain of applicability, insofar as our world resembles that domain we should expect these theories to be approximately true. Chapter Two addresses the most central question about the fundamental ontology of QFT: is it a theory of fields or of particles? Any theory describes reality in terms of some basic constituents. Historically, philosophers have assumed these to be either point particles (following Locke and the atomists) or continuous fields (following Descartes). Recent philosophical arguments suggest that the most basic ontology of QFT cannot consist of particles; it is commonly supposed that it must therefore consist of fields (Halvorson and Clifton, 2001; Malament, 1996). To the contrary, I show that two of the most persuasive arguments against particles are also arguments against the most widely advocated form of field interpretation. First, the configuration of fields, like the number of particles, cannot generally be carried over between different inequivalent representations of QFT. Since the differences between some representations encode only perspectival information about the observer, it follows that QFT states possess no objective field content. Second, arguments which rule out the possibility of particle states in interacting QFT also rule out the standard way of representing states as field configurations. So what is the most basic ontology of QFT? Chapter Three examines a possible answer, according to which fundamental reality is made up of properties, called quasi-local observables, which can be measured in regions of space and do not depend on our choice of representation. This third way has the

  9. Field-of-study mismatch and overqualification: labour market correlates and their wage penalty

    Directory of Open Access Journals (Sweden)

    Guillermo Montt

    2017-01-01

    Full Text Available Abstract Field-of-study mismatch occurs when a worker, trained in a particular field, works in another field. This study draws on the Survey of Adult Skills (PIAAC to explore how skill supply and labour market demand dynamics influence mismatch. It updates cross-national estimates on mismatch and estimates the mismatch wage penalty. Findings suggest that around 40% of workers are mismatched by field at their qualification level, 11% overqualified in their field and 13% overqualified and working outside their field. The saturation of the field in the labour market and the transferability of the fields’ skills predict the incidence of field-of-study mismatch and overqualification. Workers who are mismatched by field only suffer a wage penalty if they are overqualified.

  10. Circadian neuroendocrine physiology and electromagnetic field studies: Precautions and complexities

    International Nuclear Information System (INIS)

    Warman, G.R.; Tripp, H.M.; Harman, V.L.; Arendt, J.

    2003-01-01

    The suppression of melatonin by exposure to low frequency electromagnetic fields (EMFs) 'the melatonin hypothesis' has been invoked as a possible mechanism through which exposure to these fields may result in an increased incidence of cancer. While the effect of light on melatonin is well established, data showing a similar effect due to EMF exposure are sparse and, where present, are often poorly controlled. The current review focuses on the complexities associated with using melatonin as a marker and the dynamic nature of normal melatonin regulation by the circadian neuroendocrine axis. These are issues which the authors believe contribute significantly to the lack of consistency of results in the current literature. Recommendations on protocol design are also made which, if followed, should enable researchers to eliminate or control for many of the confounding factors associated with melatonin being an output from the circadian clock. (author)

  11. Circadian neuroendocrine physiology and electromagnetic field studies: Precautions and complexities

    Energy Technology Data Exchange (ETDEWEB)

    Warman, G.R.; Tripp, H.M.; Harman, V.L.; Arendt, J

    2003-07-01

    The suppression of melatonin by exposure to low frequency electromagnetic fields (EMFs) 'the melatonin hypothesis' has been invoked as a possible mechanism through which exposure to these fields may result in an increased incidence of cancer. While the effect of light on melatonin is well established, data showing a similar effect due to EMF exposure are sparse and, where present, are often poorly controlled. The current review focuses on the complexities associated with using melatonin as a marker and the dynamic nature of normal melatonin regulation by the circadian neuroendocrine axis. These are issues which the authors believe contribute significantly to the lack of consistency of results in the current literature. Recommendations on protocol design are also made which, if followed, should enable researchers to eliminate or control for many of the confounding factors associated with melatonin being an output from the circadian clock. (author)

  12. Numerical study of hydrofoil tip vortex fluid field

    Directory of Open Access Journals (Sweden)

    PU Jijun

    2017-01-01

    Full Text Available Three different models,k-ω,DES and LES,are conducted in the analysis of the tip vortex flow field. In order to reduce the discrete error induced by the grid,mesh refinement is applied to the area of the tip vortex core in numerical simulations. The axis and tangential velocities of the tip vortex flow field with no cavitation are calculated,and the calculated velocities agree well with the experimental results. On the basis of this process,the influence of vortex roll-up on the tip vortex pressure filed is discussed,and bubble static equilibrium is proposed by which the tip vortex cavitation inception number is computed.

  13. Hostile intent in public crowded spaces: a field study.

    Science.gov (United States)

    Eachus, Peter; Stedmon, Alex; Baillie, Les

    2013-09-01

    Hostile reconnaissance is vital to successful terrorist activity. Individuals carrying out this activity are likely to experience raised levels of stress and this will manifest itself at biological, physiological, psychological and behavioural levels, providing an opportunity for detection. A field trial was undertaken in an ecologically valid environment measuring variables considered likely to be salient during hostile intent. The parameters examined in the field trial varied in a predictable manner and suggest that stressed individuals secrete a volatile steroid based marker that could form the basis for remote detection. Thus, overall the findings of this research provide a validated model of hostile intent that can be used by other researchers to test interventions aimed at detecting or deterring hostile intent. Copyright © 2012 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  14. Recent studies of Reversed-Field Pinch reactors

    International Nuclear Information System (INIS)

    Hagenson, R.L.; Krakowski, R.A.

    1981-01-01

    The reactor prognoses of a class of confinement scheme that relies primarily on self-fields induced by axial currents flowing within a plasma column are presented. The primary focus has been placed on the toroidal Reversed-Field Pinch (RFP). At the limit of very large current densities is the gas-embedded Dense Z-Pinch (DZP), a small-radius, linear device. Past conventional RFP reactor designs are reviewed. The extention of these conventional RFP reactors to DD advanced-fuel operation is described. The implications are summarized of operating higher-density, compact RFPs as reactors, wherein the current density rather than physical dimensions are scaled. Lastly, the application of very high current densities supported in a sub-millimeter linear current channel, as embodied in the DZP reactor, is reviewed

  15. Study of neutron fields around an intense neutron generator.

    Science.gov (United States)

    Kicka, L; Machrafi, R; Miller, A

    2017-12-01

    Neutron fields in the vicinity of the newly built neutron facility, at the University of Ontario Institute of Technology (UOIT), have been investigated in a series of Monte Carlo simulations and measurements. The facility hosts a P-385 neutron generator based on a deuterium-deuterium fusion reaction. The neutron fluence at different locations around the neutron generator facility has been simulated using MCNPX 2.7E Monte Carlo particle transport program. To characterize neutron fields, three neutron sources were modeled with distributions corresponding to different incident deuteron energies of 90kV, 110kV, and 130kV. Measurements have been carried out to determine the dose rate at locations adjacent to the generator using bubble detectors (BDs). The neutron intensity was evaluated and the total dose rates corresponding to different applied acceleration potentials were estimated at various locations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Tatum Dome field study and analysis of monitoring data

    International Nuclear Information System (INIS)

    Fordham, J.W.; Fenske, P.R.

    1985-12-01

    This report is a summary and interpretation of data collected at the Tatum Dome Site during April and May 1984. In addition to raw data, description of field activities and laboratory analytical results are presented. The report also includes all analytical results of shallow well samples from the site, and chemical, mineralogical and mechanical analyses of soil samples collected during April 1985. Analysis and interpretation of laboratory analyses are included

  17. K-Organizations Accounting In Romania - A Field Study Perspective

    OpenAIRE

    Nicoleta Radneantu; Emilia Gabroveanu; Roxana Stan

    2008-01-01

    In the elaboration of this paper we started from the idea of growing the importance of a new type of organization – the knowledge organization. In this context we try to identify what change determines these organizations in accounting. Can we determine any new type of added value generating asset? Can it be included in any existent category? Is any preoccupation in Romania for this field?

  18. Digital Nomad Lifestyle : A field study in Bali

    OpenAIRE

    Haking, Julia

    2018-01-01

    The digital age has unleashed limitless opportunities and transformed how we work, play and live. As a result, more people embrace the digital nomad lifestyle to fulfill both personal and professional goals. This research assesses the advantages and disadvantages that are associated with this lifestyle. In addition, I examine the digital nomad characteristics in Bali and how the digital nomad community in Bali supports professional development. Data were collected during a two-month field stu...

  19. K - ORGANIZATIONS ACCOUNTING IN ROMANIA – A FIELD STUDY PERSPECTIVE

    Directory of Open Access Journals (Sweden)

    EMILIA GABROVEANU

    2008-01-01

    Full Text Available In the elaboration of this paper we started from the idea of growing the importance of a new type of organization – the knowledge organization. In this context we try to identify what change determines these organizations in accounting. Can we determine any new type of added value generating asset? Can it be included in any existent category? Is any preoccupation in Romania for this field?

  20. Statistical study on the occurrence of ASAID electric fields

    Directory of Open Access Journals (Sweden)

    S. Liléo

    2010-02-01

    Full Text Available The first statistical results on the occurrence of abnormal subauroral ion drifts (ASAID are presented based on electric and magnetic field measurements from the low-altitude Astrid-2 satellite. ASAID are narrow regions of rapid eastward ion drifts observed in the subauroral ionosphere. They correspond to equatorward-directed electric fields with peak amplitudes seen to vary between 45 mV/m and 185 mV/m, and with latitudinal extensions between 0.2° and 1.2° Corrected Geomagnetic Latitude (CGLat, reaching in some cases up to 3.0° CGLat.

    Opposite to subauroral ion drifts (SAID that are known to be substorm-related, ASAID are seen to occur predominantly during extended periods of low substorm activity. Our results show that ASAID are located in the vicinity of the equatorward edge of the auroral oval, mainly in the postmidnight sector between 23:00 and 03:00 magnetic local time. They are associated with a local current system with the same scale-size as the corresponding ASAID, composed by a region of downward field-aligned currents (FACs flowing in the ASAID poleward side, and a region of upward flowing FACs in the equatorward side. The FACs have densities between 0.5 and 2.0 μA/m2. The data suggest that ASAID do not contribute significantly to the reduction of the ionospheric conductivity. ASAID are seen to have life times of at least 3.5 h.

    A discussion on possible mechanisms for the generation of ASAID is presented. We speculate that the proximity of the electron to the ion plasma sheet inner boundaries and of the plasmapause to the ring current outer edge, during extended quiet times, is an important key for the understanding of the generation of ASAID electric fields.

  1. Crystallization of Calcium Carbonate in a Large Scale Field Study

    Science.gov (United States)

    Ueckert, Martina; Wismeth, Carina; Baumann, Thomas

    2017-04-01

    The long term efficiency of geothermal facilities and aquifer thermal energy storage in the carbonaceous Malm aquifer in the Bavarian Molasse Basin is seriously affected by precipitations of carbonates. This is mainly caused by pressure and temperature changes leading to oversaturation during production. Crystallization starts with polymorphic nuclei of calcium carbonate and is often described as diffusion-reaction controlled. Here, calcite crystallization is favoured by high concentration gradients while aragonite crystallization is occurring at high reaction rates. The factors affecting the crystallization processes have been described for simplified, well controlled laboratory experiments, the knowledge about the behaviour in more complex natural systems is still limited. The crystallization process of the polymorphic forms of calcium carbonate were investigated during a heat storage test at our test site in the eastern part of the Bavarian Molasse Basin. Complementary laboratory experiments in an autoclave were run. Both, field and laboratory experiments were conducted with carbonaceous tap water. Within the laboratory experiments additionally ultra pure water was used. To avoid precipitations of the tap water, a calculated amount of {CO_2} was added prior to heating the water from 45 - 110°C (laboratory) resp. 65 - 110°C (field). A total water volume of 0.5 L (laboratory) resp. 1 L (field) was immediately sampled and filtrated through 10 - 0.1

  2. Oxygen isotope studies of the Salton Sea geothermal field

    International Nuclear Information System (INIS)

    Olson, E.R.

    1978-01-01

    Interbedded shales and sandstones were drilled to a depth of 1588 metres in Sinclair Number Four Well, Salton Sea Geothermal Field. Bottom hole temperatures are approximately 290 0 C. The oxygen dels of hydrothermal and detrital calcite have a systematic relationship at any depth in the geothermal reservoir. Typical values are: vein calcite, +6 0 / 00 ; calcite in white sandstone, +10 0 / 00 ; calcite in dark gray shale, +11 0 / 00 ; calcite in light gray shale, +17 0 / 00 ; calcite in red-brown shale, +20 0 / 00 . This succession represents decreasing water-rock interaction that is also indicated by the clay mineralogy of the shales. Permeability has a marked effect on the equilibration of water and rocks at any given temperature. Original differences in permeability have resulted in partial preservation of original detrital sedimentary compositions. The fluids in the Salton Sea Geothermal Field are probabaly partially evaporated Colorado River water, and their oxygen del values vary as much as 4 0 / 00 throughout the field. Truesdell's (1974) data suggest that dissolved salts may make the water oxygen activity del as much as 6 0 / 00 greater than the concentration del in the geothermal reservoir. Such an uncertainty is a serious impediment to precise isotope geothermometry in this system.(auth.)

  3. Evaluation of bioaccumulation using in vivo laboratory and field studies.

    Science.gov (United States)

    Weisbrod, Annie V; Woodburn, Kent B; Koelmans, Albert A; Parkerton, Thomas F; McElroy, Anne E; Borgå, Katrine

    2009-10-01

    A primary consideration in the evaluation of chemicals is the potential for substances to be absorbed and retained in an organism's tissues (i.e., bioaccumulated) at concentrations sufficient to pose health concerns. Substances that exhibit properties that enable biomagnification in the food chain (i.e., amplification of tissue concentrations at successive trophic levels) are of particular concern due to the elevated long-term exposures these substances pose to higher trophic organisms, including humans. Historically, biomarkers of in vivo chemical exposure (e.g., eggshell thinning, bill deformities) retrospectively led to the identification of such compounds, which were later categorized as persistent organic pollutants. Today, multiple bioaccumulation metrics are available to quantitatively assess the bioaccumulation potential of new and existing chemicals and identify substances that, upon or before environmental release, may be characterized as persistent organic pollutants. This paper reviews the various in vivo measurement approaches that can be used to assess the bioaccumulation of chemicals in aquatic or terrestrial species using laboratory-exposed, field-deployed, or collected organisms. Important issues associated with laboratory measurements of bioaccumulation include appropriate test species selection, test chemical dosing methods, exposure duration, and chemical and statistical analyses. Measuring bioaccumulation at a particular field site requires consideration of which test species to use and whether to examine natural populations or to use field-deployed populations. Both laboratory and field methods also require reliable determination of chemical concentrations in exposure media of interest (i.e., water, sediment, food or prey, etc.), accumulated body residues, or both. The advantages and disadvantages of various laboratory and field bioaccumulation metrics for assessing biomagnification potential in aquatic or terrestrial food chains are discussed

  4. Mössbauer studies of hyperfine fields in disordered Fe CrAl

    Indian Academy of Sciences (India)

    magnetic hyperfine field, the average hyperfine field follows the ´T Tcµ3 2 law. The paramagnetic part of the hyperfine field is explained in terms of the clustering of Cr ... These alloys offer excellent systems for studying magnetic interactions. Large volumes of studies have been devoted to Heusler alloys bearing the general ...

  5. Field study of macrodispersion in a heterogeneous aquifer. I

    International Nuclear Information System (INIS)

    Boggs, J.M.; Young, S.C.; Waldrop, W.R.; Gelhar, L.W.; Adams, E.E.; Rehfeldt, K.R.

    1990-01-01

    A large-scale natural gradient tracer experiment has been conducted at a field site located at Columbus Air Force Base in northeastern Mississippi. The alluvial aquifer at the test site is composed of lenticular deposits of sand, gravel, silt and clay, and is quite heterogeneous with respect to its hydraulic properties. Ten cubic meters of a solution containing bromide and three organic tracers (pentafluorobenzoic acid, o-trifluoromethylbenzoic acid, and 2,6-difluorobenzoic acid) were injected into the aquifer at a uniform rate over a period of two days. The tracer plume was subsequently monitored in three dimensions over a 20-month period using a network of 258 multilevel sampling wells. The tracer concentration distribution of the plume at the conclusion of the experiment was highly asymmetric in the longitudinal direction. The peak tracer concentration was located only 7 m from the injection point, while the advancing side of the plume extended downgradient a distance of more than 260 m. The extreme skewness of the plume was caused by large scale spatial variations in the mean groundwater velocity along the plume travel path produced by the approximate two order-of-magnitude increase in the mean hydraulic conductivity between the near-field and far-field regions of the experimental site. The tracer mass balance during the experiment showed a declining trend between sampling events with approximately 50 percent of the injected tracer mass unaccounted for at the end of the experiment. Laboratory column experiments indicated that approximately 20 percent of the tracer mass was adsorbed to the aquifer matrix. The remaining 30 percent of the missing tracer mass was attributed to incomplete sampling coverage of the plume, particularly on the advancing side, and to a sampling bias produced by the multilevel samplers. (Author) (17 refs., 3 tabs., 11 figs.)

  6. Field study of macrodispersion in a heterogeneous aquifer. 2

    International Nuclear Information System (INIS)

    Boggs, J.M.; Rehfeldt, K.R.

    1990-01-01

    Observations of the spatial variability of the hydraulic conductivity field at the site of a large-scale natural gradient tracer experiment located at Columbus Air Force Base in Mississippi are presented. Direct measurements of hydraulic conductivity of the heterogeneous alluvial aquifer at the site were made using a variety of methods including aquifer tests, borehole flowmeter logging, double-packer tests, slug tests, and a newly developed laboratory permeameter to test undisturbed soil cores. The borehole flowmeter method was shown to be the most effective method for measuring conductivity variability. Estimates of the log hydraulic conductivity variance (σ 2 lnL ) and the horizontal and vertical correlation sales, (λ h and λ v ) of 4.5, 12 m, and 1.5 m, respectively, were calculated assuming second order stationarity of the conductivity field. Large-scale spatial variations in the mean groundwater velocity indicated by the natural gradient tracer experiment, which were shown to be a direct result of contrasts in the mean hydraulic conductivity along the plume pathway, strongly suggested the presence of a conductivity trend. The measured hydraulic conductivity data were subsequently detrended using least-squares regression to remove three-dimensional polynomials. The third-order polynomial was judged the best representation of the conductivity drift based on its overall compatibility with the groundwater flow field inferred from the tracer plume observations. Significantly lower estimates for σ 2 lnK , λ h , and λ v of 2.8, 5.3 m, and 0.7 m, respectively, were obtained from the third-order log conductivity residuals. The experience with the borehole flowmeter technique shows the feasibility of observing the statistical parameters of the hydraulic conductivity variability required for stochastic models of macrodispersion. (Author) (20 refs., 3 figs., 10 tabs.)

  7. AFRL Field Campaign to study oblique HF propagation

    Science.gov (United States)

    Colman, J. J.; Parris, R.; Dao, E. V.; Hines, J.; Caton, R.; Holmes, J.; Ober, D. M.; Sciacca, J.

    2017-12-01

    AFRL is executing a field campaign overlapping with the upcoming total eclipse on August 21st, 2017. Three Digisonde-Portable-Sounder-4D (DPS4D) Ionosondes will be deployed by AFRL in the southeastern US from South Carolina to Key West, Florida. Two existing DPS4D's at the University of Florida Gainesville and Eglin AFB will also support the campaign. The goal is to investigate HF oblique propagation and its assimilation into ionospheric models. A description of the campaign will be presented along with preliminary observations and simulations. The image shows the physical layout of the ionospheric sounder network and their geographic midpoints.

  8. Dark field X-ray microscopy for studies of recrystallization

    DEFF Research Database (Denmark)

    Ahl, Sonja Rosenlund; Simons, Hugh; Jakobsen, Anders Clemen

    2015-01-01

    We present the recently developed technique of Dark Field X-Ray Microscopy that utilizes the diffraction of hard X-rays from individual grains or subgrains at the (sub)micrometre- scale embedded within mm-sized samples. By magnifying the diffracted signal, 3D mapping of orientations and strains...... inside the selected grain is performed with an angular resolution of 0:005o and a spatial resolution of 200 nm. Furthermore, the speed of the measurements at high- intensity synchrotron facilities allows for fast non-destructive in situ determination of structural changes induced by annealing or other...

  9. A field study of the Chelyabinsk airburst impact

    Science.gov (United States)

    Jenniskens, P. M.; Popova, O. P.; Emel'yanenko, V. V.; Kartashova, A.; Biryukov, E.; Khaibrakhmanov, S.; Shuvalov, V.

    2013-12-01

    On February 15 2013 UT, a ~600 kT asteroid impact generated an airburst strong enough to cause widespread glass damage in the district of Chelyabinsk, Russia. 1,613 people requested medical assistance, while 112 people were hospitalized, two in serious condition. Starting three weeks after the event, the Russian Academy of Sciences organized a two-week field campaign, led by the Institute for Dynamics of Geospheres and the Institute of Astronomy, to investigate the extent of the damage and calibrate the entry conditions of the meteoroid by following up on the many fireball videos posted on the internet. Aim was to better understand how the airburst was generated and what damage it caused. In addition, recovered meteorites shortly after the impact were made available by Chelyabinsk State University and South Ural State University researchers to an international Chelyabinsk Airburst Consortium, to investigate their material properties. We will describe the field campaign and discuss results from the consortium research, including the meteoroid trajectory, maps of damage and injuries, and models of meteoroid fragmentation and the generation of the shock wave, and discuss the origin and dynamical history of the Chelyabinsk meteoroid.

  10. Pressure Field Study of the Tevatron Cold Compressors

    International Nuclear Information System (INIS)

    Klebaner, A.L.; Martinez, A.; Soyars, W.M.; Theilacker, J.C.

    2004-01-01

    The Fermilab Tevatron cryogenic system utilizes high-speed centrifugal cold compressors, manufactured by Ishikawajima-Harima Heavy Industries Co. Ltd. (IHI), for high-energy operations. The compressor is designed to pump 60 g/sec of 3.6 K saturated helium vapor at a pressure ratio of 2.8, with an off-design range of 40 to 70 g/sec. Operating speeds are between 40,000 and 95,000 rpm, with a speed of 80,000 rpm at the design point. Different heat loads and magnet quench performance of each of the twenty-four satellite refrigerators dictates different process pressure and flow rates of the cold compressors. Reducing the process flow rate can cause the centrifugal cold compressor to stop pumping and subsequently surge. Tests have been conducted at the Cryogenic Test Facility at Fermilab to map the pressure field and appropriate efficiency of the IHI hydrodynamic cold compressor. The information allows tuning of each of the twenty-four Tevatron satellite refrigerators to avoid cold compressor operation near the surge and choke lines. A new impeller has also been tested. The Tevatron cold compressor pressure field and efficiency data with the new impeller are presented in this paper

  11. Detailed microearthquake studies at the Cerro Prieto geothermal field

    Energy Technology Data Exchange (ETDEWEB)

    Majer, E.L. (Lawrence Berkeley Lab., CA); McEvilly, T.V.

    1981-01-01

    There appears to be an increase in seismic activity within the Cerro Prieto production zone since early 1978. The microearthquake activity is now more or less constant at a rate of 2 to 3 events per day. The b-values within the field are significantly higher inside the production zone than are those for events on faults outside of the production region. The earthquakes seem to be controlled by the Hidalgo fault, although slight clustering was observed in the center of the main production region. The earthquakes within the production zone may reflect the reservoir dynamics associated with heat and mass withdrawal. Mechanisms such as volume change, thermal stresses and weakening of materials associated with boiling (i.e., phase changes, dissolution) may all be responsible for the increased seismic activity. Although a small reinjection program has started, the pressure drawdown conditions existing within the field would imply that increased pore pressure resulting from the injection activities is not responsible for the increased seismic activity.

  12. Field studies of HT oxidation and dispersion in the environment

    International Nuclear Information System (INIS)

    Brown, R.M.; Ogram, G.L.; Spencer, F.S.; Ontario Hydro, Toronto, ON

    1988-10-01

    A tracer quantity of 3.54 TBq tritiated hydrogen (HT) was released into the atmosphere at a Chalk River, Ontario field site to determine the behaviour of HT in the environment. The primary objective was to establish the oxidation rate of HT to tritiated water (HTO) in air, soil and vegetation compartments. HTO/HT atmospheric concentration ratios observed during the release ranged from 0.14 x 10 -4 at 5 m to 7.0 x 10 -4 at 400 m distance from the release point indicating an effective oxidation rate of about 1.5% h -1 . Gas phase oxidation in the atmosphere would be less than this effective rate. Results confirm that surface soils play the dominant role in converting HT to HTO. Soil HT deposition velocities were between 2.7 x 10 -4 and 11 x 10 -4 m s -1 for an open field of varied composition, and between 3.3 x 10 -4 and 12 x 10 -4 m s -1 for a conifer forest. Soil HTO loss rates were initially 1 to 3 % h -1 averaged over the first 24 h after release. Vegetation tissue-free water tritium (TFWT) resulted from uptake of soil HTO and exchange with atmospheric HTO vapour. Upper limit HT deposition velocities to vegetation measured as TFWT in 5 species were 0.23 x 10 -7 to 6 x 10 -7 m s -1 expressed on a leaf area basis. TFWT loss rates were 5.2 to 8.1 % h -1 from about 12 to 48 h after release with low activity rain and 0.42 to 0.56 % h -1 from about 48 to 335 h. Vegetation organically-bound tritium/TFWT specific activity ratios (Bq g -1 H) were about 0.1 initially, increasing to 16 after 113 days as TFWT specific activity declined more rapidly than that of OBT. The effective HT oxidation rate, deposition velocities and HTO loss rates were in good agreement with a 1986 HT field release and previous laboratory experiments

  13. Theoretical studies of field-reversed configurations (FRC) and experimental study of the FRC during translation

    International Nuclear Information System (INIS)

    Siemon, R.E.; Armstrong, W.T.; Chrien, R.E.

    1985-01-01

    Theoretical studies of FRC stability and transport are summarized. Finite Larmor radius theories are shown to be unreliable for explaining the experimentally observed stability to tilting. Control of the n=2 rotational instability has been demonstrated in two-dimensional hybrid code simulations, and the stability appears to be described within MHD if the nearly square equilibria that result from quadrupole fields are taken into account. Simulations of the lower hybrid drift instability in parameter regimes relevant to experiments show good agreement with a non-local theory of the instability. A 1.5-dimensional transport code shows agreement with the energy confinement time but disagreement with the flux loss time observed in FRX-C. The process of FRC translation in which the plasma is formed, translated into a DC solenoid and trapped by magnetic mirrors, has been studied in the FRX-C/T experiment. Efficient transfer of particles, energy and internal magnetic flux are observed with no enhancement of loss processes over in-situ FRC experiments. The axial velocity of the FRC can be estimated reasonably well with a simple model based on conservation of energy. Internal magnetic field probing during translation shows the expected structure of poloidal field and a complex distribution of generally weak toroidal fields. Measurements of radiated power indicate that radiation is a small fraction of the total plasma power loss (typically 8%). Translation has facilitated scaling studies of confinement over a wider range of parameters than were achieved by in-situ FRX-C experiments. For example, the variable xsub(s), the ratio of the separatrix radius to the metal wall radius, has been increased to about 0.7 by allowing the FRC to expand during translation. In all cases, particle confinement times agree within a factor of two with predictions by models that assume a lower hybrid drift resistivity. However, for the conditions studied there are indications that the experimental

  14. Ultraviolet radiation penetrating vehicle glass: a field based comparative study

    International Nuclear Information System (INIS)

    Kimlin, M.G.; Parisi, A.V.

    1999-01-01

    The solar UV transmitted through automobile glass was measured in the field in two cars using a spectroradiometer. The two cars were identical except that one of the cars had all of the windows (except the windshield) tinted. The measured spectral erythemal UV on a horizontal plane with the windows fully closed was reduced in the tinted car by a factor of 42 when compared with the erythemal UV measured in the untinted car. The ambient UVA irradiances at various locations within four different makes of car and a tractor were also measured with a broad band UVA hand-held meter. The average normalized daily UVA exposure (measured with a broad band UVA meter) was 1.3 times higher in a large family sedan when compared with that in a small hatchback and the UVA exposure in a car with tinted windows was 3.8 times less than in a similar untinted car. (author)

  15. Ultraviolet radiation penetrating vehicle glass: a field based comparative study

    Science.gov (United States)

    Kimlin, M. G.; Parisi, A. V.

    1999-04-01

    The solar UV transmitted through automobile glass was measured in the field in two cars using a spectroradiometer. The two cars were identical except that one of the cars had all of the windows (except the windshield) tinted. The measured spectral erythemal UV on a horizontal plane with the windows fully closed was reduced in the tinted car by a factor of 42 when compared with the erythemal UV measured in the untinted car. The ambient UVA irradiances at various locations within four different makes of car and a tractor were also measured with a broad band UVA hand-held meter. The average normalized daily UVA exposure (measured with a broad band UVA meter) was 1.3 times higher in a large family sedan when compared with that in a small hatchback and the UVA exposure in a car with tinted windows was 3.8 times less than in a similar untinted car.

  16. Theoretical study of phosphorene tunneling field effect transistors

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Jiwon; Hobbs, Chris [SEMATECH, 257 Fuller Rd #2200, Albany, New York 12203 (United States)

    2015-02-23

    In this work, device performances of tunneling field effect transistors (TFETs) based on phosphorene are explored via self-consistent atomistic quantum transport simulations. Phosphorene is an ultra-thin two-dimensional (2-D) material with a direct band gap suitable for TFETs applications. Our simulation shows that phosphorene TFETs exhibit subthreshold slope below 60 mV/dec and a wide range of on-current depending on the transport direction due to highly anisotropic band structures of phosphorene. By benchmarking with monolayer MoTe{sub 2} TFETs, we predict that phosphorene TFETs oriented in the small effective mass direction can yield much larger on-current at the same on-current/off-current ratio than monolayer MoTe{sub 2} TFETs. It is also observed that a gate underlap structure is required for scaling down phosphorene TFETs in the small effective mass direction to suppress the source-to-drain direct tunneling leakage current.

  17. Gender Differences in the Field of Information Security Technology Management: A Qualitative, Phenomenological Study

    Science.gov (United States)

    Johnson, Marcia L.

    2013-01-01

    This qualitative study explored why there are so few senior women in the information security technology management field and whether gender played a part in the achievement of women in the field. Extensive interviews were performed to capture the lived experiences of successful women in the field regarding the obstacles and common denominators of…

  18. The history of polarisation measurements: their role in studies of magnetic fields

    Science.gov (United States)

    Wielebinski, R.

    2015-03-01

    Radio astronomy gave us new methods to study magnetic fields. Synchrotron radiation, the main cause of comic radio waves, is highly linearly polarised with the `E' vector normal to the magnetic field. The Faraday Effect rotates the `E' vector in thermal regions by the magnetic field in the line of sight. Also the radio Zeeman Effect has been observed.

  19. Experimental study of induced staggered magnetic fields in dysprosium gallium garnet (DGG)

    International Nuclear Information System (INIS)

    Steiner, M.; Corliss, L.M.; Hastings, J.M.; Blume, M.; Giordano, N.; Wolf, W.P.

    1979-01-01

    Neutron diffraction techniques have been used to study induced staggered magnetic field effects in DGG. The application of a uniform magnetic field at temperatures much greater than the Neel temperature induces a significant amount of antiferromagnetic order. The temperature and field dependences of this effect are in good agreement with recent theoretical predicions

  20. Electron beam irradiation: laboratory and field studies of cowpea seeds

    International Nuclear Information System (INIS)

    Srinivasan, K.; Chauhan, S.K.; Prasad, T.V.; Pramod, R.; Verma, V.P.; Petwal, V.; Dwivedi, J.; Bhalla, S.

    2015-01-01

    Cowpea (Vigna unguiculata) rich in protein and vitamins is emerging as one of the most important food legumes to tackle malnutrition. Pulse beetles (Callosobruchus chinensis and C. maculatus) are the pests of economic importance causing enormous losses during storage. Although various pest management strategies exist for the control of these pests, environmental concerns necessitate developing ecofriendly strategies. Electron beam (EB) irradiation has the potential to be a viable, non-chemical, residue-free strategy for management of pulse beetles during storage, but higher doses affect seed germination and viability. Hence, the present investigation was taken up to analyse the dosage effect of the irradiation on seed attributes of cowpea. Healthy cowpea seeds were irradiated with low energy electrons at different doses viz., 180, 360, 540, 720, 900, 1080, 1260, 1440 and 1620 Gy at 500 keV using the EB Accelerator facility at Raja Ramanna Centre for Advanced Technology, Indore. EB irradiated seeds were tested for physiological viz., germination, seedling vigour and vigour index and biochemical parameters viz., electrical conductivity of seed leachate, seed viability/tetrazolium test and dehydrogenase activity. Germination and vigour of the irradiated seeds were evaluated as per the ISTA Rules (ISTA, 1996). Vigour index was calculated as the product of germination percentage and seedling vigour. About 3,000 irradiated seeds from each dose were grown in the field at the Experimental farm, National Bureau of Plant Genetic Resources, New Delhi. Seeds harvested from 1500 individual plants of M 1 generation from each dose (50 seeds from each plant individually) were sown in next season and observed for chlorophyll mutations, if any. Results revealed that doses upto 1080 Gy (88%) did not affect the germination of cowpea seeds drastically as compared to untreated seeds (98%). Lower doses viz., 180 and 360 Gy had no impact on vigour components while higher doses (1080 Gy

  1. Graduate Museum Studies Curricula: Meeting the Needs of the Field

    Science.gov (United States)

    Bomar, William Frank

    2012-01-01

    The goal of this study was to assess how graduate museum studies programs are meeting the current and anticipated future needs of the museum profession. A comprehensive assessment was conducted to determine the knowledge and skills most emphasized in graduate museum studies curricula and those most valued by leading museum practitioners. A total…

  2. Integrated Study of Lithofacies Identification—A Case Study in X Field, Sabah, Malaysia

    Directory of Open Access Journals (Sweden)

    Jia Qi Ngui

    2018-02-01

    Full Text Available Understanding subsurface geology is essential for oil and gas exploration. Seismic facies interpretation is very useful in investigating this concept. The interpretation of the depositional setting of the X Field is achieved by integrating the seismic facies characteristics on 3D seismic data and well log data. Both the seismic and well log data are widely used in hydrocarbon exploration to map the subsurface, as they complement each other. Well logs yield the vertical resolution of the subsurface geology at the drilled well, whereas seismic data reveal the lateral continuity. The objective of this paper is to demonstrate the integration of 3D seismic data and well log data for lithofacies identification. Interpretation and analysis of lithofacies is carried out through the integration of the characteristics of seismic reflections with well information (logs. Horizons are interpreted based on the variation in seismic reflections on the seismic section, which is caused by the change in geology within seismic sequences. Well logs give detailed information at the points where the wells were drilled. Interpolating between these points and extrapolating away from the points into undrilled areas can be helpful in providing a better geological knowledge of an area. The result of this integrated study depicts the lithofacies in the area. This integrated study will provide a better insight with higher degree of reliability to the facies distribution and depositional setting of the X Field. The geological and geophysical aspects of the field will be documented.

  3. Preliminary study : Extremely low frequency electromagnetic field (ELF EMF) effects on the growth of plant

    International Nuclear Information System (INIS)

    Roha Tukimin; Wan Norsuhaila Wan Aziz; Rozaimah Abd Rahim; Wan Saffiey Wan Abdulah

    2010-01-01

    A research has been done to study the effects of magnetic fields on the growth of plants.Two samples of maize seedlings and green beans have been studied. Helmholtz coil systems were used as magnetic field source at frequency 50 Hz with 440 mGauss field strength. Sample characteristics such height, leaf, colour and length of roots were observed. The results show that the magnetic field influenced the growth of the sample. The sample that were exposed to the magnetic field show faster growth compared to the controlled sample. (author)

  4. Theoretical study of structure of electric field in helical toroidal plasmas

    International Nuclear Information System (INIS)

    Toda, S.; Itoh, K.

    2001-06-01

    A set of transport equations is analyzed, including the bifurcation of the electric field. The structure of the electric field is studied by use of the theoretical model for the anomalous transport diffusivities. The steep gradient of the electric field is obtained at the electric domain. The suppression of the anomalous transport diffusivity is studied in the presence of the strong shear of the electric field. The hard transition with the multiple ambipolar solutions is examined in the structure of the radial electric field. The details of the structure of the electric domain interface are investigated. (author)

  5. Study of fusion product effects in field-reversed mirrors

    International Nuclear Information System (INIS)

    Driemeyer, D.E.

    1980-01-01

    The effect of fusion products (fps) on Field-Reversed Mirror (FRM) reactor concepts has been evaluated through the development of two new computer models. The first code (MCFRM) treats fps as test particles in a fixed background plasma, which is represented as a fluid. MCFRM includes a Monte Carlo treatment of Coulomb scattering and thus provides an accurate treatment of fp behavior even at lower energies where pitch-angle scattering becomes important. The second code (FRMOD) is a steady-state, globally averaged, two-fluid (ion and electron), point model of the FRM plasma that incorporates fp heating and ash buildup values which are consistent with the MCFRM calculations. These codes have been used extensively in the development of an advanced-fuel FRM reactor design (SAFFIRE). A Catalyzed-D version of the plant is also discussed along with an investigation of the steady-state energy distribution of fps in the FRM. User guides for the two computer codes are also included

  6. A field study of pollutant deposition in radiation fog

    Energy Technology Data Exchange (ETDEWEB)

    Waldman, J.M.; Jacob, D.J.; Munger, J.W.; Hoffman, M.R.

    1986-04-01

    Deposition during fog episodes can make a significant contribution to the overall flux of pollutants in certain ecosystems. Furthermore, when atmospheric stagnation prevents normal ventilation in a region, fog deposition may become the main route of pollutant removal. Fogs can consequently exert dominant control over pollutant levels in certain atmospheres. The southern San Joaquin Valley (SJV) of California is a region prone to wintertime episodes of atmospheric stagnation. These lead to elevated pollutant concentrations and/or dense, widespread fogs. Major oil-recovery operations plus widespread agricultural and livestock feeding activities are important sources of SO/sub 2/, NO/sub X/ and NH/sub 3/ in the valley. A multifaceted program of field monitoring was conducted in the SJV during the winter 1984-1985, focusing on aspects of pollutant scavenging and removal in the fog-laden atmosphere. Concentrations of major species were measured in gas, dry aerosol and fogwater phases. In addition, depositional fluxes were monitored by surrogate-surface methods. These measurements were employed to directly assess the magnitude of removal enhancement by fog.

  7. SKB studies of the periglacial environment - report from field studies in Kangerlussuaq, Greenland 2008 and 2010

    Energy Technology Data Exchange (ETDEWEB)

    Clarhaell, Anders

    2011-03-15

    In order to reduce uncertainties in safety assessments of the planned repository of spent nuclear fuel, SKB identified the need to increase the understanding of glacial and periglacial environments. In collaboration with Posiva OY (Finland) and NWMO (Canada), SKB started the Greenland Analogue Project (GAP) in order to study the effect of climate cooling and glaciation on repository safety. GAP chose an area northeast of Kangerlussuaq, West Greenland, to be studied as a present-day analogue of a future glacial environment in both Scandinavia and Canada. The GAP, planned to run from 2009 until 2012, conducts in situ investigations of some of the parameters and processes needed to achieve a realistic understanding of how an ice sheet may impact a deep repository. In addition, the GAP will provide measurements, observations and data that may significantly improve safety assessments and risk analyses of glaciation scenarios /SKB 2011/. Issues regarding the periglacial surface environment are not included in GAP's primary focus, which has led SKB to initiate parallel activities in the same area. This new project is named The Greenland Analogue Surface Project (GRASP), and will conduct conceptual and numerical modelling of ecosystems, hydrology and near surface hydrogeology. Choosing the same investigation area for the two projects will facilitate common usage of base-line data and logistics in the field. Information from the GRASP will be applied for a better understanding of ecological and hydrological processes in a future periglacial environment in Forsmark. Annual and long-term dynamics of the permafrost are of special interest, as well as the impact of taliks on the transport of matter from the bedrock up towards the surface. This report primarily describes findings from the field season of 2010, but does also report on field work conducted by SKB in 2008. The report provides some background information on the area, describes preliminary results and set-up for

  8. SKB studies of the periglacial environment - report from field studies in Kangerlussuaq, Greenland 2008 and 2010

    International Nuclear Information System (INIS)

    Clarhaell, Anders

    2011-03-01

    In order to reduce uncertainties in safety assessments of the planned repository of spent nuclear fuel, SKB identified the need to increase the understanding of glacial and periglacial environments. In collaboration with Posiva OY (Finland) and NWMO (Canada), SKB started the Greenland Analogue Project (GAP) in order to study the effect of climate cooling and glaciation on repository safety. GAP chose an area northeast of Kangerlussuaq, West Greenland, to be studied as a present-day analogue of a future glacial environment in both Scandinavia and Canada. The GAP, planned to run from 2009 until 2012, conducts in situ investigations of some of the parameters and processes needed to achieve a realistic understanding of how an ice sheet may impact a deep repository. In addition, the GAP will provide measurements, observations and data that may significantly improve safety assessments and risk analyses of glaciation scenarios /SKB 2011/. Issues regarding the periglacial surface environment are not included in GAP's primary focus, which has led SKB to initiate parallel activities in the same area. This new project is named The Greenland Analogue Surface Project (GRASP), and will conduct conceptual and numerical modelling of ecosystems, hydrology and near surface hydrogeology. Choosing the same investigation area for the two projects will facilitate common usage of base-line data and logistics in the field. Information from the GRASP will be applied for a better understanding of ecological and hydrological processes in a future periglacial environment in Forsmark. Annual and long-term dynamics of the permafrost are of special interest, as well as the impact of taliks on the transport of matter from the bedrock up towards the surface. This report primarily describes findings from the field season of 2010, but does also report on field work conducted by SKB in 2008. The report provides some background information on the area, describes preliminary results and set-up for

  9. Pore Pressure and Field stress variation from Salt Water Injection; A case Study from Beaver Lodge Field in Williston Basin

    Science.gov (United States)

    Mohammed, R. A.; Khatibi, S.

    2017-12-01

    One of the major concerns in producing from oil and gas reservoirs in North American Basins is the disposal of high salinity salt water. It is a misconception that Hydro frack triggers Earthquakes, but due to the high salinity and density of water being pumped to the formation that has pore space of the rock already filled, which is not the case in Hydro-frack or Enhanced Oil Recovery in which fracturing fluid is pumped into empty pore space of rocks in depleted reservoirs. A review on the Bakken history showed that the concerns related to induce seismicity has increased over time due to variations in Pore pressure and In-situ stress that have shown steep changes in the region over the time. In this study, we focused on Pore pressure and field Stress variations in lower Cretaceous Inyan Kara and Mississippian Devonian Bakken, Inyan Kara is the major source for class-II salt-water disposal in the basin. Salt-water disposal is the major cause for induced seismicity. A full field study was done on Beaver Lodge Field, which has many salt-water disposal wells Adjacent to Oil and Gas Wells. We analyzed formation properties, stresses, pore-pressure, and fracture gradient profile in the field and. The constructed Mechanical Earth Model (MEM) revealed changes in pore pressure and stresses over time due to saltwater injection. Well drilled in the past were compared to recently drilled wells, which showed much stress variations. Safe mud weight Window of wells near proximity of injection wells was examined which showed many cases of wellbore instabilities. Results of this study will have tremendous impact in studying environmental issues and the future drilling and Fracking operations.

  10. Leaching of microelement contaminants: a long-term field study

    Energy Technology Data Exchange (ETDEWEB)

    Nemeth, T.; Kadar, I. [Research Inst. for Soil Science and Agricultural Chemistry, Budapest (Hungary)

    2005-04-01

    A field experiment with microelement loads was set up on loamy textured, calcareous chernozem soil formed on loess. The ploughed layer contained ca. 5% CaCO{sub 3} and 3% humus. The soil was well supplied with Ca, Mg, Mn and Cu, moderately supplied with N and K, and weakly supplied with P and Zn. The water table is at the depth of 15 m, the water balance of the area is negative, and the site is drought sensitive. Salts of the 13 examined microelements were applied at 4 doses in the spring of 1991. Treatments were arranged in a split-plot design, in a total of 104 plots with two replications. Loading rates were 0, 90, 270 and 810 kg/ha per element in the form of AlCl{sub 3}, NaAsO{sub 2}, BaCl{sub 2}, CdSO{sub 4}, K{sub 2}CrO{sub 4}, CuSO{sub 4}, HgCl{sub 2}, (NH{sub 4}){sub 6}Mo{sub 7}O{sub 24}, NiSO{sub 4}, Pb(NO{sub 3}){sub 2}, Na{sub 2}SeO{sub 3}, SrSO{sub 4}, ZnSO{sub 4}. Soil profiles of the control and the 810 kg/ha treated plots were sampled in the 3{sup rd}, 6{sup th} and 10{sup th} year of the trial. The mixed samples, consisting of 5 cores/plot were taken in 30 cm steps to 60 cm (year 1993), 90 cm (year 1996), and 290 cm (year 2000). Ammonium acetate + EDTA-soluble element content was determined. (orig.)

  11. Field of Study Choice: Using Conjoint Analysis and Clustering

    Science.gov (United States)

    Shtudiner, Ze'ev; Zwilling, Moti; Kantor, Jeffrey

    2017-01-01

    Purpose: The purpose of this paper is to measure student's preferences regarding various attributes that affect their decision process while choosing a higher education area of study. Design/ Methodology/Approach: The paper exhibits two different models which shed light on the perceived value of each examined area of study: conjoint analysis and…

  12. Quantitative aspects of transuranic and other radionuclide field studies

    International Nuclear Information System (INIS)

    Gilbert, R.O.; Simpson, J.C.; Kinnison, R.R.

    1981-01-01

    The purpose of this project is to identify, develop and communicate statistical methodology for environmental actinide studies. Significant accomplishments of FY 1980 were continued publication of TRAN-STAT, acquisition of preliminary results from a computer simulation study for evaluating estimators of average ratios, and the review of statistical estimation methods for data near detection limits

  13. Vietnamese Students at Drexel University: An Explorative Field Study.

    Science.gov (United States)

    Stevens, Kelly; Phillips, Jon

    This paper describes and presents the results of an exploratory study of six Vietnamese American students who attended an English-as-a-Second-Language class during their first year of study at Drexel University in Pennsylvania. The paper addresses the issue of the growing variety of cultures represented in today's college students by examining…

  14. Cold induced peripheral vasodilation at high altitudes- a field study

    NARCIS (Netherlands)

    Daanen, H.A.M.; Ruiten, H.J.A. van

    2000-01-01

    A significant reduction in cold-induced vasodilation (CIVD) is observed at high altitudes. No agreement is found in the literature about acclimatization effects on CIVD. Two studies were performed to investigate the effect of altitude acclimatization on CIVD. In the first study 13 male subjects

  15. Realistic edge field model code REFC for designing and study of isochronous cyclotron

    International Nuclear Information System (INIS)

    Ismail, M.

    1989-01-01

    The focussing properties and the requirements for isochronism in cyclotron magnet configuration are well-known in hard edge field model. The fact that they quite often change considerably in realistic field can be attributed mainly to the influence of the edge field. A solution to this problem requires a field model which allows a simple construction of equilibrium orbit and yield simple formulae. This can be achieved by using a fitted realistic edge field (Hudson et al 1975) in the region of the pole edge and such a field model is therefore called a realistic edge field model. A code REFC based on realistic edge field model has been developed to design the cyclotron sectors and the code FIELDER has been used to study the beam properties. In this report REFC code has been described along with some relevant explaination of the FIELDER code. (author). 11 refs., 6 figs

  16. Sounding the field: recent works in sound studies.

    Science.gov (United States)

    Boon, Tim

    2015-09-01

    For sound studies, the publication of a 593-page handbook, not to mention the establishment of at least one society - the European Sound Studies Association - might seem to signify the emergence of a new academic discipline. Certainly, the books under consideration here, alongside many others, testify to an intensification of concern with the aural dimensions of culture. Some of this work comes from HPS and STS, some from musicology and cultural studies. But all of it should concern members of our disciplines, as it represents a long-overdue foregrounding of the aural in how we think about the intersections of science, technology and culture.

  17. The Relationship of Field of Study to Current Smoking Status among College Students

    Science.gov (United States)

    Berg, Carla J.; Klatt, Colleen M.; Thomas, Janet L.; Ahluwalia, Jasjit S.; An, Lawrence C.

    2009-01-01

    Problem: No research to date has examined smoking rates among the different fields of study and smoking among college students. Thus, this study aimed to determine if smoking prevalence vary among students in the different fields of study. Method: An online health behavior survey was administered to 25,000 students (n=6,492; 26% response rate).…

  18. Mössbauer studies of hyperfine fields in disordered Fe

    Indian Academy of Sciences (India)

    Heusler-like alloy Fe2CrAl was prepared and studied. Structure determination was done by X-ray. The structure was found to conform to the B2 type. Magnetic hyperfine fields in this sample were studied by the Mössbauer effect. The Mössbauer spectra were recorded over a range of temperature from 40 to 296 K. The ...

  19. Comparative Administrative Law: Outlining a Field of Study

    Directory of Open Access Journals (Sweden)

    Susan Rose-Ackerman

    2010-10-01

    Full Text Available Comparative administrative law is emerging as a distinct field of inquiry after a period of neglect. To demonstrate this claim, the authors summarize their edited volume on the topic – a collection that aims to stimulate research across legal systems and scholarly disciplines. After a set of historical reflections, the authors consider key topics at the intersection of administrative and constitutional law, including the contested issue of administrative independence. Two further sections highlight tensions between expertise and accountability, drawing insights from economics and political science. The essay then considers the changing boundaries of the administrative state – both the public–private distinction and the links between domestic and transnational regulatory bodies, such as the European Union. The essay concludes with reflections on a core concern of administrative law: the way individuals and organizations across different systems test and challenge the legitimacy of public authority. Le droit administratif comparé est en train de se manifester comme domaine d’étude distinct suite à une période pendant laquelle il a été négligé. Pour démontrer cette affirmation, les auteurs présentent un sommaire du volume à ce sujet dont ils dirigent la publication – une collection qui vise à stimuler la recherche au sein de divers systèmes juridiques et diverses disciplines d’érudition. Après une série de réflexions historiques, les auteurs traitent de questions–clés qui relèvent en même temps du droit administratif et du droit constitutionnel, y compris la question controversée de l’indépendance administrative. Deux autres sections mettent en lumière des tensions entre l’expertise et l’obligation de rendre compte, puisant dans les sciences économique et politique. L’article traite ensuite des limites changeantes de l’état administratif – d’une part, quant à la distinction public–privé et d

  20. Status report on geochemical field results from Atlantic study sites

    International Nuclear Information System (INIS)

    Wilson, T.R.S.; Thomson, J.; Hydes, D.J.; Colley, S.

    1983-01-01

    This report summarises the results of preliminary geochemical investigations at three North Atlantic study areas. The two eastern sites, on the Cape Verde abyssal plain (CV2) and east of Great Meteor Seamount (GME) were visited during 1982. The results presented are preliminary. Studies in the western Atlantic, close to the Nares Abyssal Plain study site are more detailed and are presented in a separate paper. The report shows for the first time the relative redox status of the three sites. The differences are unexpectedly large, the most reduced cores being recovered at GME and the most oxidised at CV2. The sporadic nature of Recent sediment accumulation at these sites is also emphasised. In order to place these preliminary results in context their relevance to the production of mathematical system models is discussed in a closing section. The necessity for such models to rest on sound foundations of geochemical understanding is noted. Suggestions on future research priorities are offered for discussion. (author)

  1. Conduct of a personal radiofrequency electromagnetic field measurement study: proposed study protocol.

    Science.gov (United States)

    Röösli, Martin; Frei, Patrizia; Bolte, John; Neubauer, Georg; Cardis, Elisabeth; Feychting, Maria; Gajsek, Peter; Heinrich, Sabine; Joseph, Wout; Mann, Simon; Martens, Luc; Mohler, Evelyn; Parslow, Roger C; Poulsen, Aslak Harbo; Radon, Katja; Schüz, Joachim; Thuroczy, György; Viel, Jean-François; Vrijheid, Martine

    2010-05-20

    The development of new wireless communication technologies that emit radio frequency electromagnetic fields (RF-EMF) is ongoing, but little is known about the RF-EMF exposure distribution in the general population. Previous attempts to measure personal exposure to RF-EMF have used different measurement protocols and analysis methods making comparisons between exposure situations across different study populations very difficult. As a result, observed differences in exposure levels between study populations may not reflect real exposure differences but may be in part, or wholly due to methodological differences. The aim of this paper is to develop a study protocol for future personal RF-EMF exposure studies based on experience drawn from previous research. Using the current knowledge base, we propose procedures for the measurement of personal exposure to RF-EMF, data collection, data management and analysis, and methods for the selection and instruction of study participants. We have identified two basic types of personal RF-EMF measurement studies: population surveys and microenvironmental measurements. In the case of a population survey, the unit of observation is the individual and a randomly selected representative sample of the population is needed to obtain reliable results. For microenvironmental measurements, study participants are selected in order to represent typical behaviours in different microenvironments. These two study types require different methods and procedures. Applying our proposed common core procedures in future personal measurement studies will allow direct comparisons of personal RF-EMF exposures in different populations and study areas.

  2. Urban children in natural environments: a field study in sociobiology

    Science.gov (United States)

    Ruth Hamilton Allen

    1977-01-01

    Six nature programs for urban children were studied from 1970 to 1974. Social networks in the camping programs and children's choices of locations for various leisure activities were examined. Return rates were found to correlate significantly with the intricacy of the social networks.

  3. Field study of earth tempered swine ventilation systems

    Energy Technology Data Exchange (ETDEWEB)

    Goetsch, W.D.; Peterson, W.H.; Muehling, A.J.

    1981-01-01

    Four earth-tube heat exchanger systems for heating and cooling the ventilation air for swine farrowing and nursery buildings were studied. Results show appreciable winter heating and summer cooling from the earth tubes with minimal variation in the temperature of the discharge air. 5 refs.

  4. Flipped Classroom Research and Trends from Different Fields of Study

    Science.gov (United States)

    Zainuddin, Zamzami; Halili, Siti Hajar

    2016-01-01

    This paper aims to analyse the trends and contents of flipped classroom research based on 20 articles that report on flipped learning classroom initiatives from 2013-2015. The content analysis was used as a methodology to investigate methodologies, area of studies, technology tools or online platforms, the most frequently used keywords and works…

  5. Field study on nematode resistance in Nelore-breed cattle

    NARCIS (Netherlands)

    Bricarello, P A; Zaros, L G; Coutinho, L L; Rocha, R A; Kooyman, F N J; De Vries, E; Gonçalves, J R S; Lima, L G; Pires, A V; Amarante, A F T

    2007-01-01

    The present study evaluated Nelore cattle with different degrees of resistance to natural infections by gastrointestinal nematodes. One hundred weaned male cattle, 11-12 months of age, were kept on the same pasture and evaluated from October 2003 to February 2004. Faecal and blood samples were

  6. [Homeless women with psychiatric disorders -- a field study].

    Science.gov (United States)

    Torchalla, Iris; Albrecht, Friederike; Buchkremer, Gerhard; Längle, Gerhard

    2004-07-01

    The aim of the study was to investigate the psychosocial situation of all homeless women in a southern German university town. The scope, structure and whereabouts of the target group were initially unknown. 17 of 22 homeless women identified agreed to participate in an extensive study including the Structured Clinical Interview for DSM-IV (SKID-I). The prevalence of diagnosed psychiatric disorders was 71 %; the leading disorder was substance abuse/dependence (43 %), followed by anxiety disorders (35 %) and schizophrenia (12 %). Multiple diagnoses were made in 35 % of the women. Striking features were the often early onset of homelessness and the reticence in seeking help. The flight from violence was a crucial precipitant of the loss of the home and should also be discussed in the context of the development of the psychiatric disorders. This study is the first involving women outside major cities. Precipitant situation, need for help and help-seeking pattern appear to deviate markedly from those of homeless men. The results should be verified in further gender-specific studies.

  7. Study of fractures in Precambrian crystalline rocks using field ...

    Indian Academy of Sciences (India)

    1992, 1993), however, have found through investigations from tunnel projects in crystalline rock that the .... comprising amphibolites mainly and some horn- blende schist occur as elongated patches, lenses and bands ... The 'south Purulia shear zone' (Baidya 1992) occurs in the study area which trends almost. E–W and ...

  8. ArcGIS studies and field relationships of Paleoproterozoic mafic ...

    Indian Academy of Sciences (India)

    lar trends (e.g., Srivastava 2006a, b; Srivastava and. Figure 1. Simplified geological map of the Dharwar Craton showing the principal distribution of Paleoproterozoic mafic dykes (modified after French and Heaman 2010; Srivastava et al. 2014c). Detailed mafic dyke map of the studied region, the red box marked on map, ...

  9. Introducing transnationalism studies to the field of public diplomacy

    Czech Academy of Sciences Publication Activity Database

    Exnerová, Věra

    2017-01-01

    Roč. 23, č. 2 (2017), s. 186-199 ISSN 1321-6597 R&D Projects: GA ČR GA15-21829S Institutional support: RVO:68378009 Keywords : China * domestic structure * Public diplomacy * transnational societal space * transnationalism studies Subject RIV: AD - Politology ; Political Sciences OBOR OECD: Political science

  10. A Field Study Training Program on Wastewater Lagoon Systems.

    Science.gov (United States)

    Water and Wastewater Technical School, Neosho, MO.

    This publication is a text and reference manual for operating personnel of both large and small wastewater lagoon systems with support from the Environmental Protection Agency (EPA). As a text, this inservice training manual is intended to be used in a correspondence course wherein the trainee or operator would read and study each chapter before…

  11. H2+ molecule in strong magnetic fields, studied by the method of linear combinations of orbitals

    International Nuclear Information System (INIS)

    de Melo, L.C.; Das, T.K.; Ferreira, R.C.; Miranda, L.C.M.; Brandi, H.S.

    1978-01-01

    We have studied the ground state of the H 2 + molecular ion in the presence of a homogeneous magnetic field, basing this study on a linear combination of atomic orbitals obtained from the hydrogen atom in a magnetic field. The calculations have shown that this scheme is adequate to describe the binding energy of the molecule at field strengths up to approximately 10 10 G

  12. Balancing Control and Complexity in Field Studies of Neonicotinoids and Honey Bee Health

    OpenAIRE

    Suryanarayanan, Sainath

    2013-01-01

    Amidst ongoing declines in honey bee health, the contributory role of the newer systemic insecticides continues to be intensely debated. Scores of toxicological field experiments, which bee scientists and regulators in the United States have looked to for definitive causal evidence, indicate a lack of support. This paper analyzes the methodological norms that shape the design and interpretation of field toxicological studies. I argue that contemporary field studies of honey bees and pesticide...

  13. Construction of an interim storage field using recovered municipal solid waste incineration bottom ash: Field performance study.

    Science.gov (United States)

    Sormunen, Laura Annika; Kolisoja, Pauli

    2017-06-01

    The leaching of hazardous substances from municipal solid waste incineration (MSWI) bottom ash (BA) has been studied in many different scales for several years. Less attention has been given to the mechanical performance of MSWI BA in actual civil engineering structures. The durability of structures built with this waste derived material can have major influence on the functional properties of such structures and also the potential leaching of hazardous substances in the long term. Hence, it is necessary to properly evaluate in which type of structures MSWI BA can be safely used in a similar way as natural and crushed rock aggregates. In the current study, MSWI BA treated with ADR (Advance Dry Recovery) technology was used in the structural layers of an interim storage field built within a waste treatment centre. During and half a year after the construction, the development of technical and mechanical properties of BA materials and the built structures were investigated. The aim was to compare these results with the findings of laboratory studies in which the same material was previously investigated. The field results showed that the mechanical performance of recovered BA corresponds to the performance of natural aggregates in the lower structural layers of field structures. Conversely, the recovered MSWI BA cannot be recommended to be used in the base layers as such, even though its stiffness properties increased over time due to material aging and changes in moisture content. The main reason for this is that BA particles are prone for crushing and therefore inadequate to resist the higher stresses occurring in the upper parts of road and field structures. These results were in accordance with the previous laboratory findings. It can thus be concluded that the recovered MSWI BA is durable to be used as a replacement of natural aggregates especially in the lower structural layers of road and field structures, whereas if used in the base layers, an additional base

  14. A Field Study of Scale Economies in Software Maintenance

    OpenAIRE

    Rajiv D. Banker; Sandra A. Slaughter

    1997-01-01

    Software maintenance is a major concern for organizations. Productivity gains in software maintenance can enable redeployment of Information Systems resources to other activities. Thus, it is important to understand how software maintenance productivity can be improved. In this study, we investigate the relationship between project size and software maintenance productivity. We explore scale economies in software maintenance by examining a number of software enhancement projects at a large fi...

  15. System studies in PA: Development of process influence diagram (PID) for SFR-1 repository near-field + far-field

    Energy Technology Data Exchange (ETDEWEB)

    Stenhouse, M.J. [Monitor Scientific, LLC, Denver, CO (United States); Miller, W.M.; Chapman, N.A. [QuantiSci Ltd., Melton Mowbray (United Kingdom)

    2001-05-01

    Scenario development is a key component of the performance assessment (PA) process for radioactive waste disposal, the primary objective being to ensure that all relevant factors associated with the future evolution of the repository system are properly considered in PA. As part of scenario development, a list of features, events and processes (FEPs) are identified and assembled, representing the Process System, with interactions/influences between FEPs incorporated in a Process Influence Diagram (PID). This report documents the technical work conducted between 1997 and the end of 1999 under the Systems Studies Project. The overall objective of this project has been the construction of a PID for the SFR-1 repository (final repository for reactor waste), this PID being the first stage in the identification of scenarios to describe future evolution of this repository. The PIDs discussed in this report have been created using two software applications: existing commercial software (Business Modeller, Infotool AB. Stockholm, Sweden) and, more recently, a newly developed software tool SPARTA (Enviros QuantiSci, Henley, U.K.). Although the focus of this report is on the application of SPARTA to PID development, it is important to document the work carried out prior to SPARTA being available, in order to provide a complete record of the entire SFR-1 PID development effort as well as preserving the context of the multi-year project. Following a description of the different disposal sections of the SFR-1 and the various near-field barriers, the sequential development (i.e. near-field of Silo, BMA, BLA, BTF sections; far-field; integrated near-field + far-field) of the PID for SFR-1 repository system using Business Modeller is described. Owing to the complexity of the repository, in terms of number of both different disposal sections (Silo, BLA, BMA, BTF) and barriers associated with each section, the two-dimensional (2D) PID created for SFR-1 using Business Modeller is

  16. System studies in PA: Development of process influence diagram (PID) for SFR-1 repository near-field + far-field

    International Nuclear Information System (INIS)

    Stenhouse, M.J.; Miller, W.M.; Chapman, N.A.

    2001-05-01

    Scenario development is a key component of the performance assessment (PA) process for radioactive waste disposal, the primary objective being to ensure that all relevant factors associated with the future evolution of the repository system are properly considered in PA. As part of scenario development, a list of features, events and processes (FEPs) are identified and assembled, representing the Process System, with interactions/influences between FEPs incorporated in a Process Influence Diagram (PID). This report documents the technical work conducted between 1997 and the end of 1999 under the Systems Studies Project. The overall objective of this project has been the construction of a PID for the SFR-1 repository (final repository for reactor waste), this PID being the first stage in the identification of scenarios to describe future evolution of this repository. The PIDs discussed in this report have been created using two software applications: existing commercial software (Business Modeller, Infotool AB. Stockholm, Sweden) and, more recently, a newly developed software tool SPARTA (Enviros QuantiSci, Henley, U.K.). Although the focus of this report is on the application of SPARTA to PID development, it is important to document the work carried out prior to SPARTA being available, in order to provide a complete record of the entire SFR-1 PID development effort as well as preserving the context of the multi-year project. Following a description of the different disposal sections of the SFR-1 and the various near-field barriers, the sequential development (i.e. near-field of Silo, BMA, BLA, BTF sections; far-field; integrated near-field + far-field) of the PID for SFR-1 repository system using Business Modeller is described. Owing to the complexity of the repository, in terms of number of both different disposal sections (Silo, BLA, BMA, BTF) and barriers associated with each section, the two-dimensional (2D) PID created for SFR-1 using Business Modeller is

  17. A field study to evaluate runoff quality from green roofs.

    Science.gov (United States)

    Vijayaraghavan, K; Joshi, U M; Balasubramanian, R

    2012-03-15

    Green (vegetated) roofs are emerging as practical strategies to improve the environmental quality of cities. However, the impact of green roofs on the storm water quality remains a topic of concern to city planners and environmental policy makers. This study investigated whether green roofs act as a source or a sink of various metals (Na, K, Ca, Mg, Al, Fe, Cu, Cd, Pb, Zn, Mn, Cr, Ni, Li and Co), inorganic anions (NO3-, NO2-, PO4(3-), SO4(2-), Cl-, F- and Br-) and cation (NH4+). A series of green roof assemblies were constructed. Four different real rain events and several artificial rain events were considered for the study. Results showed that concentrations of most of the chemical components in runoff were highest during the beginning of rain events and subsided in the subsequent rain events. Some of the important components present in the runoff include Na, K, Ca, Mg, Li, Fe, Al, Cu, NO3-, PO4(3-) and SO4(2-). However, the concentration of these chemical components in the roof runoff strongly depends on the nature of substrates used in the green roof and the volume of rain. Based on the USEPA standards for freshwater quality, we conclude that the green roof used in this study is reasonably effective except that the runoff contains significant amounts of NO3- and PO4(3-). Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Bioventing and air sparging: a field research study

    International Nuclear Information System (INIS)

    Moore, B.J.; Armstrong, J.E.; Hardisty, P.E.; Dupont, R.R.

    1997-01-01

    A study was conducted at Gulf Canada Resources' Strachan Gas Plant in Alberta, in which bioventing and air sparging were used individually and in combination to remediate a free-phase natural gas condensate plume estimated to cover approximately 65,000 m 2 . The condensate was composed of light hydrocarbons. Benzene, toluene, ethylbenzene and total xylenes (BTEX) made up a large portion of the dissolved plume. The objectives of the bioventing program were to: (1) study the use of biodegradation respiration rates and hydrocarbon vapour concentrations as indicators of soil clean-up progress, (2) study the effectiveness of bioventing during winter operations, (3) assess the degree of soil clean-up achievable through bioventing, and (4) evaluate the economics of bioventing. It was shown that bioventing is an economical in-situ remediation technique, costing about $10/m 3 . Air sparging involves the injection of air below the groundwater table to remove dissolved phased contaminants in-situ. The objectives of the air sparging program were to: (1) determine the zone of influence achievable through air sparging, (2) assess bioventing for treating hydrocarbon vapours introduced into the unsaturated zone during sparging, and (3) evaluate hydrocarbon mass removal effectiveness due to volatilization and biodegradation. It was shown that 90 per cent of the saturated zone hydrocarbon mass was removed during eight months of air sparging. 11 refs., 1 tab., 5 figs

  19. Numerical studies of fermionic field theories at large-N

    International Nuclear Information System (INIS)

    Dickens, T.A.

    1987-01-01

    A description of an algorithm, which may be used to study large-N theories with or without fermions, is presented. As an initial test of the method, the spectrum of continuum QCD in 1 + 1 dimensions is determined and compared to previously obtained results. Exact solutions of 1 + 1 dimensional lattice versions of the free fermion theory, the Gross-Neveu model, and QCD are obtained. Comparison of these exact results with results from the numerical algorithm is used to test the algorithms, and more importantly, to determine the errors incurred from the approximations used in the numerical technique. Numerical studies of the above three lattice theories in higher dimensions are also presented. The results are again compared to exact solutions for free fermions and the Gross-Neveu model; perturbation theory is used to derive expansions with which the numerical results for QCD may be compared. The numerical algorithm may also be used to study the euclidean formulation of lattice gauge theories. Results for 1 + 1 dimensional euclidean lattice QCD are compared to the exact solution of this model

  20. Experimental Study of Magnetic Field Effect on dc Corona Discharge in Low Vacuum

    Science.gov (United States)

    Elabbas, K.

    2014-09-01

    In the present paper, an attempt was made to investigate the effect of applying a transverse magnetic field on the dc corona discharge behavior in low vacuum. In general, two experiments were carried out in this work: the first is the ionization-region magnetic field experiment, and the second was the drift region magnetic field experiment. In these experiments, permanent magnets were used to produce magnetic field. The degree of vacuum used in this test was 0.4×105 Pa. It is found that the effect of the magnetic field increases as the degree of vacuum increases. It is also seen from this study that the corona current values are higher with magnetic fields than without magnetic fields. The experimental results indicate that the enhancement of the magnetic field near the wire discharge electrode has a significant influence on the increment of the discharge current. The effect of the magnetic field on the discharge current is the most significant with the negative corona discharges rather than with positive corona discharge. In contrast to, the curves were demonstrated that the application of magnetic fields in drift region magnetic field does not significantly change the corona discharge current. Discharge characteristics of magnetically enhanced corona discharges, extracted from this study, can be applied to various industrial applications, such as, in an electrostatic enhancement filter for the purpose of capturing fine particles, and as effective method for production of high ozone concentrations in a generator as compared to the ultraviolet (UV) radiation method.

  1. Petrophysical study of Szolnok Formation, Endrod gas field,

    Directory of Open Access Journals (Sweden)

    Abdel Moktader A. El Sayed

    2017-03-01

    Full Text Available Results of both porosity and permeability can be used by geologists, petrophysicists, and petroleum engineers to evaluate reservoir rock, heterogeneity, and pore space history through the time of deposition and lithifaction. On the other hand, reservoir quality as well as reservoir classification could be performed based on these data correlation. The Szolnok Formation is composed mainly of turbidity elastic deposits while siltstones are intercalated by sandstone beds and streaks of marls. In the present study, 213 core samples are obtained from the Szolnok Formation of the Great Hungarian plain, Hungary. Both horizontal and vertical permeability are measured. The Szolnok Formation has two main lithologic groups: 1. clean sandstone (141 samples and 2. siltstone – marl (72 samples, it can easily differentiate between good, intermediate or even bad reservoirs. Acoustic laboratory measurements have been carried out for only 30 sandstone rock samples parallel to the bedding plane (horizontal. This paper aims to evaluate some petrophysical relationships. On the other hand, both Wyllie and Raymer models were applied for porosity estimation from seismic velocity. It is worthy to mention that reservoir diagnosis of the Szolnok Formation was our target as well. Both the porosity and permeability variation range characterizing the detected lithologic facies of the Szolnok Formation are useful for reservoir zonation. The relationship between helium and mercury porosity for whole studied samples and sandstone samples as well, are supported by a high correlation coefficient and allow its application for prediction of porosity while it reduces costs and time of laboratory measurements. The evaluation of different calculated equations for porosity from compressional wave velocity data of the Szolnok Formation are studied and the relationship between velocity and porosity displays a clear inverse trend. The comparison between laboratory porosity and sonic

  2. Electric field gradient studies in SnSe

    Energy Technology Data Exchange (ETDEWEB)

    Pal, G. [IUC, DAE Facilities (India); Sebastian, K.C. [M.S. University, Physics Department (India); Chintalapudi, S.N. [IUC, DAE Facilities (India); Somayajulu, D.R.S. [M.S. University, Physics Department (India)

    1999-09-15

    The EFG in IV-VI compound semiconductor SnSe was studied using two hyperfine interaction techniques, namely, TDPAC and Moessbauer spectroscopy. The EFG in this material increases sharply up to 300 K and thereafter at higher temperatures it gets saturated. However, the conductivity increases steadily at all the temperatures. The conductivity curve has two slopes. The first portion is due to the population of shallow Cd acceptor levels. Thus, in SnSe also the variation of the EFG with temperature is complex, as in other medium-gap semiconductors.

  3. Electric field gradient studies in SnSe

    International Nuclear Information System (INIS)

    Pal, G.; Sebastian, K.C.; Chintalapudi, S.N.; Somayajulu, D.R.S.

    1999-01-01

    The EFG in IV-VI compound semiconductor SnSe was studied using two hyperfine interaction techniques, namely, TDPAC and Moessbauer spectroscopy. The EFG in this material increases sharply up to 300 K and thereafter at higher temperatures it gets saturated. However, the conductivity increases steadily at all the temperatures. The conductivity curve has two slopes. The first portion is due to the population of shallow Cd acceptor levels. Thus, in SnSe also the variation of the EFG with temperature is complex, as in other medium-gap semiconductors

  4. Use of thermoluminescent dosimetry in gamma radiation fields studies

    International Nuclear Information System (INIS)

    Carron, W.

    1987-01-01

    The depth-dose curves for gamma rays in material of interest to agronomy were obtained using lithium fluoride thermoluminescent dosimeters. The dose conversion factors for LiF were determined from curves of the absorved dose versus depth in water, wood and soil. Mathematics equations were chosen to best fit these curves. In the view of the results we came to the conclusion that in the studied materials the absorved radiation dose presents a great variation to the depth and could be correlated through of the exponential regression. (author)

  5. Study on propagation properties of laser guiding EMP in a finite magnetic field

    International Nuclear Information System (INIS)

    Xia Xinren; Yin Chengyou

    2009-01-01

    The geometric model of laser plasma channel (LPC) guiding electromagnetic pulse (EMP) in a finite electromagnetic field is created; when LPC is in lossy gas the propagation properties of the normal modes of LPC guiding EMP are studied; and then the wave equation of longitudinal electormagnetic field and the relationship between transverse and longitudinal electromagnetic field in anisotropic medium are derived under the generalized cylindrical coordinate system. By applying the boundary conditions of electromagnetic fields, the strict characteristic equation of mode propagation for LPC guiding EMP is deduced, and the effects of plasma parameters, surrounding material and external magnetic field on propagation are discussed. The results show that the propagation properties of magnetized LPC guiding EMP are easy to be controlled compared with those without external magnetic field or an infinite external magnetic field applied. (authors)

  6. Study of leakage currents in pCVD diamonds as function of the magnetic field

    CERN Document Server

    Müller, S; Schneider, M; Sabellek, A; Schmanau, M; Rühle, C; Schneider, T; Hall-Wilton, R

    2009-01-01

    pCVD diamond sensors are regularly used as beam loss monitors in accelerators by measuring the ionization of the lost particles. In the past these beam loss monitors showed sudden increases in the dark leakage current without beam losses and these erratic leakage currents were found to decrease, if magnetic fields were present. Here we report on a systematic study of leakage currents inside a magnetic field. The decrease of erratic currents in a magnetic field was confirmed. On the contrary, diamonds without erratic currents showed an increase of the leakage current in a magnetic field perpendicular to the electric field for fields up to 0.6T, for higher fields it decreases. A preliminary model is introduced to explain the observations.

  7. Mapping Women's and Gender Studies in the Academic Field in Slovenia

    Science.gov (United States)

    Gaber, Milica Antic

    2017-01-01

    The aim of the present paper is to map the development of women's and gender studies (WGS) in the academic field in Slovenia. Slovenia is the first of the former Yugoslav state republics in which WGS have succeeded in entering the academic field and becoming part of institutionalised university study. In this paper we will ask the following…

  8. Field-Study Science Classrooms as Positive and Enjoyable Learning Environments

    Science.gov (United States)

    Zaragoza, Julien M.; Fraser, Barry J.

    2017-01-01

    We investigated differences between field-study classrooms and traditional science classrooms in terms of the learning environment and students' attitudes to science, as well as the differential effectiveness of field-study classrooms for students differing in sex and English proficiency. A modified version of selected scales from the What Is…

  9. International Relations as a Field of Study in the Canadian System of Higher Education

    Science.gov (United States)

    Istomina, Kateryna

    2015-01-01

    The research presents an attempt to investigate the current state of international relations as a field of study in the context of higher education system in Canada. It contains a general overview of the field of study, focusing predominantly on the role and function of the given academic discipline. The scientific investigation covers the issue…

  10. Field of Study, Learning Styles, and Language Learning Strategies of University Students: Are There Any Relations?

    Science.gov (United States)

    Sahragard, Rahman; Khajavi, Yaser; Abbasian, Reza

    2016-01-01

    The present study aimed to investigate the possible relationships between field of study, learning style preferences, and language learning strategies among university students majoring in the fields of arts and humanities, science, engineering, social sciences, and English as a foreign language. To this end, 376 university students completed the…

  11. Field study of the indoor environment in a Danish prison

    DEFF Research Database (Denmark)

    Dogbeh, Audrey; Jomaas, Grunde; Bjarløv, Søren Peter

    2015-01-01

    The indoor environment in a Danish prison was evaluated based on measurements made during the summer season of temperature, relative humidity and carbon dioxide, as well as through carefully conducted surveys among the inmates. The temperatures in the cells were high and well beyond common levels...... with their general indoor environment and all responding inmates expressed dissatisfaction with the thermal climate. Dissatisfaction was mostly caused by a lack of airflow and air movement in the space as well as excessive direct sunlight from the windows. Security is a leading factor in the design of prisons, so...... a compromise must be found to ensure that the building can comply with minimum health and comfort standards. The findings of this study can be used as background for recommendations for renovation of prison buildings....

  12. High Field Studies for CLIC Accelerating Structures Development

    CERN Document Server

    Profatilova, I

    2017-01-01

    Compact Linear Collider RF structures need to be able to achieve the very high average accelerating gradient of 100 MV/m. One of the main challenges in reaching such high accelerating gradients is to avoid vacuum electrical breakdown within CLIC accelerating structures. Accelerating structure tests are carried out in the klystron-based test stands known as the XBoxes. In order to investigate vacuum breakdown phenomena and its statistical characteristics in a simpler system and get results in a faster way, pulsed dc systems have been developed at CERN. To acquire sufficient breakdown data in a reasonable period of time, high repetition rate pulse generators are used in the systems for breakdown studies, so-called pulsed dc system. This paper describes the pulsed dc systems and the two high repetition rate circuits, which produce high-voltage pulses for it, available at CERN.

  13. A Study on Human Resources Development in Nuclear Field

    International Nuclear Information System (INIS)

    Moon, Keehwan; Lee, M. K.; Kim, S. S.; Nam, J. H.; Won, B. C.; Lee, D. S; Hwang, I. A.; Seo, M. W.

    2011-11-01

    The study encompasses 4 major parts, each results being described here under: Various policy alternatives through supply-demand analysis of domestic nuclear skilled manpower are suggested. Human resources development programs of main educational organizations in domestic and overseas are comprehensively reviewed. Establishment of 'Integrated Management Organization' which can combine and manage domestic educational organizations' educational functions is necessary to efficiently deal with the increased educational demand and the shift of educational paradigm from supply-driven to needs-driven education and to make nuclear energy export sustainable. And road map on human resource development to efficiently accomplish 'Integrated Management Organization's mission is suggested. It is provided that an overall strategies for the reasonable educational program reflecting the good practices with their implications in overseas nuclear education programs

  14. Studies of HED Plasmas with Self-Generated Magnetic Field

    Energy Technology Data Exchange (ETDEWEB)

    Medvedev, Mikhail [Univ. of Kansas, Lawrence, KS (United States)

    2016-02-08

    High-amplitude sub-Larmor-scale electromagnetic turbulence is ubiquitous in high-energy density environments, such as laboratory plasmas produced by high-intensity lasers, e.g., NIF, Omega-EP, Trident, and others, and in astrophysical and space plasmas, e.g., at high-Mach-number collisionless shocks in weakly magnetized plasmas upstream regions of quasi-parallel shocks, sites of magnetic reconnection and others. Studies of plasmas and turbulence in these environments are important for fusion energy sciences and the inertial confinement concept, in particular, as well as to numerous astrophysical systems such as gamma-ray bursts, supernovae blast waves, jets of quasars and active galactic nuclei, shocks in the interplanetary medium, solar flares and many more. Such turbulence can be of various origin and thus have rather different properties, from being purely magnetic (Weibel) turbulence to various types of electromagnetic turbulence (for example, whistler wave turbulence or turbulence produced by filamentation or Weibel-type streaming instability), to purely electrostatic Langmuir turbulence. In this project we use analytical and numerical tools to study the transport, radiative, and magneto-optical properties of plasmas with sub-Larmor-scale turbulence. We discovered the connection of transport/diffusion properties to certain spectral benchmark features of (jitter) radiation produced by the plasma and radiation propagation through it. All regimes, from the relativistic to non-relativistic, were thoroughly investigated and predictions were made for laboratory plasmas and astrophysical plasmas. Thus, all the tasks outlined in the proposal were fully and successfully accomplished.

  15. AN ANALYSIS OF THE STUDY PLAN OF THE PROFESSIONALLY ORIENTED BACHELOR STUDY FIELD OF MULTIMEDIA IN ECONOMIC PRACTISE

    Directory of Open Access Journals (Sweden)

    VONDRA, Zdeněk

    2014-12-01

    Full Text Available This paper focuses on the study field of Multimedia in Economic Practise which has been taught at the University of Economics in Prague since 2011. This study field has its first graduates which is the reason for a re-examination of the profile of graduates according to the structure of subjects in the study plan. This paper describes evolution of the study field, its content, main idea and structure of its students. It presents two main groups of occupations for graduates with dependence on requirements for student’s additional independent activities beyond the study. The analytical part shows five examples of comparison of the course relevance according to the opinion of students and academic staff. The conclusions from the survey will enable academic staff of the study field to the reconsider the future development of the study field.

  16. Marketing determinants of the choice of field of studies

    Directory of Open Access Journals (Sweden)

    Halemba, Piotr

    2017-09-01

    Full Text Available Considerations presented in this article are aimed at giving an answer to the following research question – Which elements of universities’ marketing activity influence the acquisition of students the most? The presented research question arises from the goal defined for the research which involved finding clues concerning the way of conducting marketing activities enabling the acquisition of a number of new students satisfying the strategy of a university. Additionally, the answer to the question formulated this way will be juxtaposed with new reality of the functioning of universities in Poland, which is associated with changes introduced by the Ministry of Science and Higher Education in the academic year 2016/2017. Own research was conducted on the group of almost all people (96% who started studying at the Faculty of Sports and Tourism Management of the Academy of Physical Education in Katowice in the academic year 2016/2017. The obtained data show that among the marketing activities conducted by universities, promotion was the strongest incentive encouraging students to choose a particular university.

  17. COMPARATIVE STUDY ON MAIN SOLVENCY ASSESSMENT MODELS FOR INSURANCE FIELD

    Directory of Open Access Journals (Sweden)

    Daniela Nicoleta SAHLIAN

    2015-07-01

    Full Text Available During the recent financial crisis of insurance domain, there were imposed new aspects that have to be taken into account concerning the risks management and surveillance activity. The insurance societies could develop internal models in order to determine the minimum capital requirement imposed by the new regulations that are to be adopted on 1 January 2016. In this respect, the purpose of this research paper is to offer a real presentation and comparing with the main solvency regulation systems used worldwide, the accent being on their common characteristics and current tendencies. Thereby, we would like to offer a better understanding of the similarities and differences between the existent solvency regimes in order to develop the best regime of solvency for Romania within the Solvency II project. The study will show that there are clear differences between the existent Solvency I regime and the new approaches based on risk and will also point out the fact that even the key principles supporting the new solvency regimes are convergent, there are a lot of approaches for the application of these principles. In this context, the question we would try to find the answer is "how could the global solvency models be useful for the financial surveillance authority of Romania for the implementation of general model and for the development of internal solvency models according to the requirements of Solvency II" and "which would be the requirements for the implementation of this type of approach?". This thing makes the analysis of solvency models an interesting exercise.

  18. Review of Studies Concerning Electromagnetic Field (EMF) Exposure Assessment in Europe: Low Frequency Fields (50 Hz–100 kHz)

    Science.gov (United States)

    Gajšek, Peter; Ravazzani, Paolo; Grellier, James; Samaras, Theodoros; Bakos, József; Thuróczy, György

    2016-01-01

    We aimed to review the findings of exposure assessment studies done in European countries on the exposure of the general public to low frequency electric and magnetic fields (EMFs) of various frequencies. The study shows that outdoor average extremely low frequency magnetic fields (ELF-MF) in public areas in urban environments range between 0.05 and 0.2 µT in terms of flux densities, but stronger values (of the order of a few µT) may occur directly beneath high-voltage power lines, at the walls of transformer buildings, and at the boundary fences of substations. In the indoor environment, high values have been measured close to several domestic appliances (up to the mT range), some of which are held close to the body, e.g., hair dryers, electric shavers. Common sources of exposure to intermediate frequencies (IF) include induction cookers, compact fluorescent lamps, inductive charging systems for electric cars and security or anti-theft devices. No systematic measurement surveys or personal exposimetry data for the IF range have been carried out and only a few reports on measurements of EMFs around such devices are mentioned. According to the available European exposure assessment studies, three population exposure categories were classified by the authors regarding the possible future risk analysis. This classification should be considered a crucial advancement for exposure assessment, which is a mandatory step in any future health risk assessment of EMFs exposure. PMID:27598182

  19. Review of Studies Concerning Electromagnetic Field (EMF Exposure Assessment in Europe: Low Frequency Fields (50 Hz–100 kHz

    Directory of Open Access Journals (Sweden)

    Peter Gajšek

    2016-09-01

    Full Text Available We aimed to review the findings of exposure assessment studies done in European countries on the exposure of the general public to low frequency electric and magnetic fields (EMFs of various frequencies. The study shows that outdoor average extremely low frequency magnetic fields (ELF-MF in public areas in urban environments range between 0.05 and 0.2 µT in terms of flux densities, but stronger values (of the order of a few µT may occur directly beneath high-voltage power lines, at the walls of transformer buildings, and at the boundary fences of substations. In the indoor environment, high values have been measured close to several domestic appliances (up to the mT range, some of which are held close to the body, e.g., hair dryers, electric shavers. Common sources of exposure to intermediate frequencies (IF include induction cookers, compact fluorescent lamps, inductive charging systems for electric cars and security or anti-theft devices. No systematic measurement surveys or personal exposimetry data for the IF range have been carried out and only a few reports on measurements of EMFs around such devices are mentioned. According to the available European exposure assessment studies, three population exposure categories were classified by the authors regarding the possible future risk analysis. This classification should be considered a crucial advancement for exposure assessment, which is a mandatory step in any future health risk assessment of EMFs exposure.

  20. Review of Studies Concerning Electromagnetic Field (EMF) Exposure Assessment in Europe: Low Frequency Fields (50 Hz-100 kHz).

    Science.gov (United States)

    Gajšek, Peter; Ravazzani, Paolo; Grellier, James; Samaras, Theodoros; Bakos, József; Thuróczy, György

    2016-09-01

    We aimed to review the findings of exposure assessment studies done in European countries on the exposure of the general public to low frequency electric and magnetic fields (EMFs) of various frequencies. The study shows that outdoor average extremely low frequency magnetic fields (ELF-MF) in public areas in urban environments range between 0.05 and 0.2 µT in terms of flux densities, but stronger values (of the order of a few µT) may occur directly beneath high-voltage power lines, at the walls of transformer buildings, and at the boundary fences of substations. In the indoor environment, high values have been measured close to several domestic appliances (up to the mT range), some of which are held close to the body, e.g., hair dryers, electric shavers. Common sources of exposure to intermediate frequencies (IF) include induction cookers, compact fluorescent lamps, inductive charging systems for electric cars and security or anti-theft devices. No systematic measurement surveys or personal exposimetry data for the IF range have been carried out and only a few reports on measurements of EMFs around such devices are mentioned. According to the available European exposure assessment studies, three population exposure categories were classified by the authors regarding the possible future risk analysis. This classification should be considered a crucial advancement for exposure assessment, which is a mandatory step in any future health risk assessment of EMFs exposure.

  1. A statistical study of high-altitude electric fields measured on the Viking satellite

    International Nuclear Information System (INIS)

    Lindqvist, P.A.; Marklund, G.T.

    1990-01-01

    Characteristics of high-altitude data from the Viking electric field instrument are presented in a statistical study based on 109 Viking orbits. The study is focused in particular on the signatures of and relationships between various parameters measured by the electric field instrument, such as the parallel and transverse (to B) components of the electric field instrument, such as electric field variability. A major goal of the Viking mission was to investigate the occurrence and properties of parallel electric fields and their role in the auroral acceleration process. The results in this paper on the altitude distribution of the electric field variability confirm earlier findings on the distribution of small-scale electric fields and indicate the presence of parallel fields up to about 11,000 km altitude. The directly measured parallel electric field is also investigated in some detail. It is in general directed upward with an average value of 1 mV/m, but depends on, for example, altitude and plasma density. Possible sources of error in the measurement of the parallel field are also considered and accounted for

  2. Study of the electric Held in HTS tape caused by perpendicular AC magnetic field

    International Nuclear Information System (INIS)

    Roiberg, V; Kopansky, F.

    2004-01-01

    Full Text: In a previous work we studied the influence of AC magnetic fields on voltage-currents (V-I) characteristics of high temperature superconducting (HTS) multi filament BSCC0-2223 tapes. It was found that AC magnetic fields perpendicular to the ab plane (the wide surface of the tape) cause a linear decrease of the critical current (IC) with amplitude of the AC magnetic field. The degradation of IC in .AC field was explained by the geometrical model according to which the transport current floe: is confined to the central zone of the tape where .AC field does not penetrate. For deeper understanding of the observed phenomena we carried out a study of the time dependence of the electric field during the cycle of AC field. At the same time we expanded the frequency range to low frequencies down to 1 Hz. The main results of the work are as following. 1. The time modulation of the electric field E in the HTS tape carrying transport DC current has the double frequency relating to AC magnetic field. 2. In field amplitudes less than 70 G the electric field modulation decreases with increasing frequency in opposite to its well-pronounced increase in higher AC field amplitudes. Alcove 70 G, the electric field increases with increasing the frequency of the external magnetic field. The wave forms of the electric field are different in both amplitudes ranges. 3. E-I curves of the tape in low amplitudes are frequency independent and coincide with E-l curves in AC field with intensity equal to the AC field amplitude. 4. In high AC field amplitudes, a strong dependence of the E-I curves on frequency is observed in the frequency range of 1-40 Hz and no dependence is observed in higher frequencies. Our results suggest that a combination of the geometrical model with flux creep concepts is necessary for a better understanding of the electric field behavior in our measurement conditions

  3. STUDY OF THE INFLUENCE OF MAGNETIC FIELD ON SOME BIOLOGICAL CHARACTERISTICS OF ZEA MAIS

    Directory of Open Access Journals (Sweden)

    A ALADJADJIYAN

    2002-11-01

    Full Text Available The effect of the static magnetic field of 0,15 Т induction on the maize seeds was studied. The germinating energy and seed germination were detected. The fresh weight and the shoot length were measured. The absorption spectra and the specific electroconductivity of the water extract from seeds were registered. It was detected that the magnetic field stimulated the shoot development and led to the increase of the germinating energy, germination, fresh weight and shoot length. The extinction of the samples treated with a magnetic field increased by about 20 %. The highest values of the treated sample parameters were obtained after 10-min exposure in the magnetic field.

  4. Study of electric and magnetic fields on transmission lines using a computer simulation program

    International Nuclear Information System (INIS)

    Robelo Mojica, Nelson

    2011-01-01

    A study was conducted to determine and reduce levels of electric and magnetic fields with different configurations used by the Instituto Costarricense de Electricidad in power transmission lines in Costa Rica. The computer simulation program PLS-CADD with EPRI algorithm has been used to obtain field values close to those actual to lines easements that have worked to date. Different configurations have been compared on equal terms and the lowest levels of electric and magnetic fields are determined. The most appropriate configuration of the tower has been obtained and therefore has decreased exposure to electromagnetic fields people, without affecting the energy demand of the population. (author) [es

  5. SU-E-T-596: Axillary Nodes Radiotherapy Boost Field Dosimetric Impact Study: Oblique Field and Field Optimization in 3D Conventional Breast Cancer Radiation Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Su, M [Mount Sinai School of Medicine, Elmhurst, NY (United States); Sura, S

    2014-06-01

    Purpose: To evaluate dosimetric impact of two axillary nodes (AX) boost techniques: (1) posterior-oblique optimized field boost (POB), (2) traditional posterior-anterior boost (PAB) with field optimization (O-PAB), for a postmastectomy breast patient with positive axillary lymph nodes. Methods: Five patients, 3 left and 2 right chest walls, were included in this study. All patients were simulated in 5mm CT slice thickness. Supraclavicular (SC) and level I/II/III AX were contoured based on the RTOG atlas guideline. Five treatment plans, (1) tangential chest wall, (2) oblique SC including AX, (3) PAB, O-PAB and POB, were created for each patient. Three plan sums (PS) were generated by sum one of (3) plan with plan (1) and (2). The field optimization was done through PS dose distribution, which included a field adjustment, a fractional dose, a calculation location and a gantry angle selection for POB. A dosimetric impact was evaluated by comparing a SC and AX coverage, a PS maximum dose, an irradiated area percentage volume received dose over 105% prescription dose (V105), an ipsi-laterial mean lung dose (MLD), an ipsi-laterial mean humeral head dose (MHHD), a mean heart dose (MHD) (for left case only) and their DVH amount these three technique. Results: O-PAB, POB and PAB dosimetric results showed that there was no significant different on SC and AX coverage (p>0.43) and MHD (p>0.16). The benefit of sparing lung irradiation from PAB to O-PAB to POB was significant (p<0.004). PAB showed a highest PS maximum dose (p<0.005), V105 (p<0.023) and MLD (compared with OPAB, p=0.055). MHHD showed very sensitive to the patient arm positioning and anatomy. O-PAB convinced a lower MHHD than PAB (p=0.03). Conclusion: 3D CT contouring plays main role in accuracy radiotherapy. Dosimetric advantage of POB and O-PAB was observed for a better normal tissue irradiation sparing.

  6. [Studies in quantum field theory: Progress report, April 1, 1991--March 31, 1992

    International Nuclear Information System (INIS)

    Bender, C.M.

    1992-01-01

    Professors Bender, Bernard, and Shrauner, Assistant Professors Ogilvie and Goltermann, Research Assistant Professors Visser and Petcher, and Research Associate Rivas are currently conducting research in many areas of high energy theoretical and mathematical physics. These areas include: lattice gauge calculations of masses and weak matrix elements; strong-coupling approximation; low-energy effective field theories; classical solutions of non-Abelian gauge theories; mean-field approximation in quantum field theory; path integral and coherent state representations in quantum field theory; the nature of perturbation theory in large order; quark condensation in QCD; chiral fermion theories on the lattice; the 1/N expansion in quantum field theory; effective potential and action in quantum field theories, including QCD; studies of the early universe and inflation; quantum gravity. This work is described in detail in the body of this proposal

  7. (Studies in quantum field theory: Progress report, April 1, 1991--March 31, 1992)

    Energy Technology Data Exchange (ETDEWEB)

    Bender, C M

    1992-01-01

    Professors Bender, Bernard, and Shrauner, Assistant Professors Ogilvie and Goltermann, Research Assistant Professors Visser and Petcher, and Research Associate Rivas are currently conducting research in many areas of high energy theoretical and mathematical physics. These areas include: lattice gauge calculations of masses and weak matrix elements; strong-coupling approximation; low-energy effective field theories; classical solutions of non-Abelian gauge theories; mean-field approximation in quantum field theory; path integral and coherent state representations in quantum field theory; the nature of perturbation theory in large order; quark condensation in QCD; chiral fermion theories on the lattice; the 1/N expansion in quantum field theory; effective potential and action in quantum field theories, including QCD; studies of the early universe and inflation; quantum gravity. This work is described in detail in the body of this proposal.

  8. Study of electrons photoemitted from field emission tips. Progress report, July 1, 1979-March 1, 1980

    International Nuclear Information System (INIS)

    Reifenberger, R.

    1980-02-01

    Photo-induced field emission is a technique which studies electrons that have been photoemitted from a field emission tip. This new experimental method promises to combine the proven utility of both field emission and photoemission for investigating the electronic states near a metal surface. The primary objective of the research being performed is to investigate photo-induced field emitted electrons using a tuneable cw dye laser. To fully exploit this continuously tuneable photon source, a differential energy analyzer is being constructed to allow energy resolved measurements of the photo-field emitted electrons. This report describes the progress made in implementing experiments on photo-induced field emission from July 1979 to March 1980

  9. Study of the leakage field of magnetic force microscopy thin-film tips using electron holography

    NARCIS (Netherlands)

    Frost, B.G.; van Hulst, N.F.; Lunedei, E.; Matteucci, G.; Rikkers, E.

    1996-01-01

    Electron holography is applied for the study of the leakage field of thin-film ferromagnetic tips used as probes in magnetic force microscopy. We used commercially available pyramidal tips covered o­n o­ne face with a thin NiCo film, which were then placed in a high external magnetic field directed

  10. Engaging the Borders: Empathy, Religious Studies, and Pre-Professional Fields

    Science.gov (United States)

    Trothen, Tracy J.

    2016-01-01

    This article proposes that religious studies instructors can gain pedagogical insights regarding the value and teaching of empathy from pre-professional health care and counseling fields. I present research findings from these fields to support claims that empathic skills are teachable. I then show that empathy has been established within the…

  11. A soil technological study on effectuating and maintaining adequate playing conditions of grass sports fields

    NARCIS (Netherlands)

    Wijk, van A.L.M.

    1980-01-01

    Playing conditions of grass sports fields have been studied focusing on top layer soil strength meeting the requirements of usage. In a field investigation a reproducible soil strength criterion was found from firmness appraisals and simultaneous measurements of soil strength. From

  12. Causes of incident visual field loss in a general elderly population: the Rotterdam study

    NARCIS (Netherlands)

    Skenduli-Bala, Elisa; de Voogd, Simone; Wolfs, Roger C. W.; van Leeuwen, Redmer; Ikram, M. Kamran; Jonas, Jost B.; Bakker, Douwe; Hofman, Albert; de Jong, Paulus T. V. M.

    2005-01-01

    To determine the incidence and causes of visual field loss (VFL) in a general elderly population. Central visual fields of both eyes were examined with suprathreshold perimetry in 3761 persons aged 55 years or older and free of VFL at baseline from the population-based Rotterdam Study. Goldmann

  13. Supporting Medical Students to Do International Field Research: A Case Study

    Science.gov (United States)

    Pearson, Stephen; Parr, Jennifer; Ullah, Zafar; Omar, Maye

    2014-01-01

    Field research can benefit medical students' learning through experiential engagement with research and personal exposure to foreign health systems. However, the off-campus nature of the activity raises challenges for teachers. This article presents a case study that illustrates the benefits and challenges of organising a field research project…

  14. Higher Education as a Field of Study and Research in Europe

    Science.gov (United States)

    Kehm, Barbara M.

    2015-01-01

    This article describes the emergence of higher education as a field of research, scholarship and study. In the first part, the meaning of higher education as a field of research is defined contrasting Europe and the US. Then, the institutional basis of higher education research in Europe is analysed (learned societies, institutes and centres,…

  15. Water liquid-vapor interface subjected to various electric fields: A molecular dynamics study

    Science.gov (United States)

    Nikzad, Mohammadreza; Azimian, Ahmad Reza; Rezaei, Majid; Nikzad, Safoora

    2017-11-01

    Investigation of the effects of E-fields on the liquid-vapor interface is essential for the study of floating water bridge and wetting phenomena. The present study employs the molecular dynamics method to investigate the effects of parallel and perpendicular E-fields on the water liquid-vapor interface. For this purpose, density distribution, number of hydrogen bonds, molecular orientation, and surface tension are examined to gain a better understanding of the interface structure. Results indicate enhancements in parallel E-field decrease the interface width and number of hydrogen bonds, while the opposite holds true in the case of perpendicular E-fields. Moreover, perpendicular fields disturb the water structure at the interface. Given that water molecules tend to be parallel to the interface plane, it is observed that perpendicular E-fields fail to realign water molecules in the field direction while the parallel ones easily do so. It is also shown that surface tension rises with increasing strength of parallel E-fields, while it reduces in the case of perpendicular E-fields. Enhancement of surface tension in the parallel field direction demonstrates how the floating water bridge forms between the beakers. Finally, it is found that application of external E-fields to the liquid-vapor interface does not lead to uniform changes in surface tension and that the liquid-vapor interfacial tension term in Young's equation should be calculated near the triple-line of the droplet. This is attributed to the multi-directional nature of the droplet surface, indicating that no constant value can be assigned to a droplet's surface tension in the presence of large electric fields.

  16. Studies of field distortions in a time projection chamber for the International Linear Collider

    International Nuclear Information System (INIS)

    Zenker, Klaus

    2014-12-01

    The International Linear Collider (ILC) will allow to do precision measurements of Standard Model parameter and to search for new physics. The ILD detector concept, which is developed for the ILC, uses a Time Projection Chamber (TPC) as central tracking device. The momentum resolution goal for the ILD TPC is δ(1/p t ) ≅ 10 -4 (GeV/c) -1 at a magnetic field of B=3.5 T. Field distortions of the magnetic or electric field inside the sensitive volume of the TPC distort the momentum measurements. Therefore, one needs to keep them under control and correct them with high precision. In this thesis the main sources of field distortions in the TPC are identified and their effects are determined. Furthermore, possibilities to reduce the identified field distortions are presented. One known source of distortions of the electric field are ions, produced by the gas amplification in the TPC anode, that drift into the sensitive volume of the TPC. In the first part of this work the creation of these ions in Gas Electron Multiplier (GEM), which are used for the gas amplification, is studied. It will be shown that the resulting field distortions are not acceptable at the ILD TPC. By tuning the parameters of the gas amplification at the anode the field distortion can be reduced, which is shown in measurements and simulations. In addition measurements using a modified GEM show that it is possible to further reduce the field distortions with such a GEM. In the second part of this work field distortions arising at boundaries between individual readout modules are investigated using simulation studies. It will be shown in simulations, which are verified by measurement results, that these field distortions significantly influence the readout module performance. Based on the simulation results the GEM based readout module developed at DESY is optimised and the field distortions are reduced. These performance improvements could also be verified in measurements. Finally, a laser

  17. A quality control study of the accuracy of patient positioning in irradiation of pelvic fields

    International Nuclear Information System (INIS)

    Creutzberg, Carien L.; Althof, Vincent G.M.; Hoog, Marjan de; Visser, Andries G.; Huizenga, Henk; Wijnmaalen, Arendjan; Levendag, Peter C.

    1996-01-01

    Purpose: Determining and improving the accuracy of patient positioning in pelvic fields. Methods and Materials: Small pelvic fields were studied in 16 patients treated for urological cancers using a three-field isocentric technique. Large pelvic fields were studied in 17 gynecological cancer patients treated with anterior and posterior (AP-PA) parallel opposed fields. Quantitative analysis of 645 megavolt images and comparison to 82 simulation images were carried out. Results: Small pelvic fields: for the position of the patient in the field, standard deviations of the difference between simulation (SIM) and treatment (MV) images were 3.4 mm in the lateral direction, 5.3 mm in the cranio-caudal direction, and 4.8 mm in the ventro-dorsal direction. Alterations in the positioning technique were made and tested. Large pelvic fields: differences between simulation and treatment images for the position of the patient in the field were 4 mm [1 standard deviation (SD)] in the lateral direction and 6.5 mm in the cranio-caudal direction. A systematic shift of the treatment field in the cranial direction had occurred in the majority of patients. A positioning technique using laser lines and marking of the caudal field border was shown to be more accurate. Conclusion: Studies of positioning accuracy in routine irradiation techniques are needed to obtain data for definition of the margins for each treatment site at each institution. Random variations should be kept at a minimum by monitoring and improving positioning techniques. Treatment verification by megavolt imaging or film should be used to detect and correct systematic variations early in the treatment series

  18. A study: Effect of Students Peer Assisted Learning on Magnetic Field Achievement

    International Nuclear Information System (INIS)

    Mueanploy, Wannapa

    2016-01-01

    This study is the case study of Physic II Course for students of Pathumwan Institute of Technology. The purpose of this study is: 1) to develop cooperative learning method of peer assisted learning (PAL), 2) to compare the learning achievement before and after studied magnetic field lesson by cooperative learning method of peer assisted learning. The population was engineering students of Pathumwan Institute of Technology (PIT’s students) who registered Physic II Course during year 2014. The sample used in this study was selected from the 72 students who passed in Physic I Course. The control groups learning magnetic fields by Traditional Method (TM) and experimental groups learning magnetic field by method of peers assisted learning. The students do pretest before the lesson and do post-test after the lesson by 20 items achievement tests of magnetic field. The post-test higher than pretest achievement significantly at 0.01 level. (paper)

  19. A study: Effect of Students Peer Assisted Learning on Magnetic Field Achievement

    Science.gov (United States)

    Mueanploy, Wannapa

    2016-04-01

    This study is the case study of Physic II Course for students of Pathumwan Institute of Technology. The purpose of this study is: 1) to develop cooperative learning method of peer assisted learning (PAL), 2) to compare the learning achievement before and after studied magnetic field lesson by cooperative learning method of peer assisted learning. The population was engineering students of Pathumwan Institute of Technology (PIT’s students) who registered Physic II Course during year 2014. The sample used in this study was selected from the 72 students who passed in Physic I Course. The control groups learning magnetic fields by Traditional Method (TM) and experimental groups learning magnetic field by method of peers assisted learning. The students do pretest before the lesson and do post-test after the lesson by 20 items achievement tests of magnetic field. The post-test higher than pretest achievement significantly at 0.01 level.

  20. Using a verbal prompt to increase protein consumption in a hospital setting: a field study

    NARCIS (Netherlands)

    Zanden, van der L.D.T.; Essen, van H.; Kleef, van E.; Wijk, de R.A.; Trijp, van J.C.M.

    2015-01-01

    Background: Sufficient protein intake among hospitalized patients may contribute to faster recovery and a decrease in healthcare costs. Nevertheless, hospitalized patients are often found to consume too little protein. This field study explored the success of a small, inexpensive intervention

  1. PCC Airfield Pavement Response During Thaw-Weakening Periods: A Field Study

    Science.gov (United States)

    1996-05-01

    This investigation is part of the Cold Regions Research and Engineering Laboratory's (CRREL) on-going characterization of pavement performance in seasonal frost areas. As part of the research, CRREL conducted several field studies for the Federal Avi...

  2. Effective field study of ising model on a double perovskite structure

    Energy Technology Data Exchange (ETDEWEB)

    Ngantso, G. Dimitri; El Amraoui, Y. [LMPHE, (URAC 12), Faculté des Sciences, Université Mohammed V, Rabat (Morocco); Benyoussef, A. [LMPHE, (URAC 12), Faculté des Sciences, Université Mohammed V, Rabat (Morocco); Center of Materials and Nanomaterials, MAScIR, Rabat (Morocco); Hassan II Academy of Science and Technology, Rabat (Morocco); El Kenz, A., E-mail: elkenz@fsr.ac.ma [LMPHE, (URAC 12), Faculté des Sciences, Université Mohammed V, Rabat (Morocco)

    2017-02-01

    By using the effective field theory (EFT), the mixed spin-1/2 and spin-3/2 Ising ferrimagnetic model adapted to a double perovskite structure has been studied. The EFT calculations have been carried out from Ising Hamiltonian by taking into account first and second nearest-neighbors interactions and the crystal and external magnetic fields. Both first- and second-order phase transitions have been found in phase diagrams of interest. Depending on crystal-field values, the thermodynamic behavior of total magnetization indicated the compensation phenomenon existence. The hysteresis behaviors are studied by investigating the reduced magnetic field dependence of total magnetization and a series of hysteresis loops are shown for different reduced temperatures around the critical one. - Highlights: • Magnetic properties of double perovskite Structure have been studied. • Compensation temperature has been observed below the critical temperature. • Hysteresis behaviors have been studied.

  3. Effective field study of ising model on a double perovskite structure

    International Nuclear Information System (INIS)

    Ngantso, G. Dimitri; El Amraoui, Y.; Benyoussef, A.; El Kenz, A.

    2017-01-01

    By using the effective field theory (EFT), the mixed spin-1/2 and spin-3/2 Ising ferrimagnetic model adapted to a double perovskite structure has been studied. The EFT calculations have been carried out from Ising Hamiltonian by taking into account first and second nearest-neighbors interactions and the crystal and external magnetic fields. Both first- and second-order phase transitions have been found in phase diagrams of interest. Depending on crystal-field values, the thermodynamic behavior of total magnetization indicated the compensation phenomenon existence. The hysteresis behaviors are studied by investigating the reduced magnetic field dependence of total magnetization and a series of hysteresis loops are shown for different reduced temperatures around the critical one. - Highlights: • Magnetic properties of double perovskite Structure have been studied. • Compensation temperature has been observed below the critical temperature. • Hysteresis behaviors have been studied.

  4. A video-image study of electrolytic flow structure in parallel electric-magnetic fields

    International Nuclear Information System (INIS)

    Gu, Z.H.; Fahidy, T.Z.

    1987-01-01

    The structure of free convective flow propagating from a vertical cathode into the electrolyte bulk has been studied via video-imaging. The enhancing effect of imposed horizontal uniform magnetic fields is manifest by vortex propagation and bifurcating flow

  5. Effects of the Ride Environment on Passenger Activities : A Field Study on Intercity Trains

    Science.gov (United States)

    1979-01-01

    A three-part field study of passenger activities (e.g. reading, writing, talking, sleeping) was conducted on intercity Amtrak trains in the northeastern United States to determine the relationships between the ride environment, subjective passenger c...

  6. The effects of the ride environment on passenger activities : a field study on intercity trains

    Science.gov (United States)

    1979-01-01

    A three-part field study of passenger activities (e.g. reading, writing, talking, sleeping) was conducted on intercity Amtrak trains in the northeastern United States to determine the relationships between the ride environment, subjective passenger c...

  7. Use of terrestrial field studies in the derivation of bioaccumulation potential of chemicals

    Science.gov (United States)

    van den Brink, Nico W.; Arblaster, Jennifer A.; Bowman, Sarah R.; Conder, Jason M.; Elliott, John E.; Johnson, Mark S.; Muir, Derek C.G.; Natal-da-Luz, Tiago; Rattner, Barnett A.; Sample, Bradley E.; Shore, Richard F.

    2016-01-01

    Field-based studies are an essential component of research addressing the behavior of organic chemicals, and a unique line of evidence that can be used to assess bioaccumulation potential in chemical registration programs and aid in development of associated laboratory and modeling efforts. To aid scientific and regulatory discourse on the application of terrestrial field data in this manner, this article provides practical recommendations regarding the generation and interpretation of terrestrial field data. Currently, biota-to-soil-accumulation factors (BSAFs), biomagnification factors (BMFs), and bioaccumulation factors (BAFs) are the most suitable bioaccumulation metrics that are applicable to bioaccumulation assessment evaluations and able to be generated from terrestrial field studies with relatively low uncertainty. Biomagnification factors calculated from field-collected samples of terrestrial carnivores and their prey appear to be particularly robust indicators of bioaccumulation potential. The use of stable isotope ratios for quantification of trophic relationships in terrestrial ecosystems needs to be further developed to resolve uncertainties associated with the calculation of terrestrial trophic magnification factors (TMFs). Sampling efforts for terrestrial field studies should strive for efficiency, and advice on optimization of study sample sizes, practical considerations for obtaining samples, selection of tissues for analysis, and data interpretation is provided. Although there is still much to be learned regarding terrestrial bioaccumulation, these recommendations provide some initial guidance to the present application of terrestrial field data as a line of evidence in the assessment of chemical bioaccumulation potential and a resource to inform laboratory and modeling efforts.

  8. Can DMCO Detect Visual Field Loss in Neurological Patients? A Secondary Validation Study

    DEFF Research Database (Denmark)

    Olsen, Ane Sophie; Steensberg, Alvilda Thougaard; la Cour, Morten

    2017-01-01

    Unrecognized visual field loss is caused by a range of blinding eye conditions as well as serious brain diseases. The commonest cause of asymptomatic visual field loss is glaucoma. No screening tools have been proven cost-effective. Damato Multifixation Campimetry Online (DMCO), an inexpensive...... online test, has been evaluated as a future cost-beneficial tool to detect glaucoma. To further validate DMCO, this study aimed to test DMCO in a preselected population with neurological visual field loss. Methods : The study design was an evaluation of a diagnostic test. Patients were included...

  9. Development of Visual Field Screening Procedures: A Case Study of the Octopus Perimeter

    OpenAIRE

    Turpin, Andrew; Myers, Jonathan S.; McKendrick, Allison M.

    2016-01-01

    Purpose We develop a methodology for designing perimetric screening procedures, using Octopus perimeters as a case study. Methods The process has three stages: analytically determining specificity and number of presentations required for different multisampling suprathreshold schemes at a single location of the visual field, ranking visual field locations by their positive predictive value (PPV) for glaucoma, and determining a pass/fail criteria for the test. For the case study the Octopus G-...

  10. Market conditions of higher education services in Ukraine in the field of study “Management”

    Directory of Open Access Journals (Sweden)

    Zakharova Oksana Volodymyrivna

    2016-06-01

    Full Text Available The aim of the research is to study market conditions of higher education services in the field of study “Management” and the characteristics of the degree of social responsibility of leading Ukrainian universities. The paper analyzes the situation of higher education services market in Ukraine in the field of study “Management”. The leading regions of Ukraine in the real number of applications and the degree of actual use of the license are discussed. The structure of the distribution of budget places, of applications and of enrolled students in the field of study “Management” by regions of Ukraine is given. Four field-leaders in entrance campaign for the last three years that is Kiev, Kharkiv, Lviv, Dnipropetrovsk are analyzed. The main characteristics of a socially responsible institution are singled out: an active position to attract students, the high quality of vocational training, international cooperation and assistance in employment of graduates. Five leading universities of Ukraine are analyzed in the field of study “Management” according to the degree of social responsibility on the basis of the data presented on their official websites. The basic directions to increase public opinion about the field of study “Management” in Ukraine are offered.

  11. Classical study of the rovibrational dynamics of a polar diatomic molecule in static electric fields

    Energy Technology Data Exchange (ETDEWEB)

    Inarrea, Manuel, E-mail: manuel.inarrea@unirioja.e [Area de Fisica, Universidad de la Rioja, E-26006 Logrono (Spain); Salas, J. Pablo [Area de Fisica, Universidad de la Rioja, E-26006 Logrono (Spain); Gonzalez-Ferez, Rosario [Instituto ' Carlos I' de Fisica Teorica y Computacional, Universidad de Granada, E-18071 Granada (Spain); Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Granada, E-18071 Granada (Spain); Schmelcher, Peter [Theoretische Chemie, Physikalisch-Chemisches Institut, D-69120 Heidelberg (Germany); Physikalisches Institut, Universitaet Heidelberg, D-69120 Heidelberg (Germany)

    2010-01-04

    We study the classical dynamics of a polar diatomic molecule in the presence of a strong static homogeneous electric field. Our full rovibrational investigation includes the interaction with the field due to the permanent electric dipole moment and the polarizability of the molecule. Using the LiCs molecule as a prototype, we explore the stability of the equilibrium points and their bifurcations as the field strength is increased. The phase space structure and its dependence on the energy and field strength are analyzed in detail. We demonstrate that depending on the field strength and on the energy, the phase space is characterized either by regular features or by small stochastic layers of chaotic motion.

  12. Spin-resolved tunneling studies of the exchange field in EuS/Al bilayers.

    Science.gov (United States)

    Xiong, Y M; Stadler, S; Adams, P W; Catelani, G

    2011-06-17

    We use spin-resolved electron tunneling to study the exchange field in the Al component of EuS/Al bilayers, in both the superconducting and normal-state phases of the Al. Contrary to expectation, we show that the exchange field H(ex) is a nonlinear function of applied field, even in applied fields that are well beyond the EuS coercive field. Furthermore, the magnitude H(ex) is unaffected by the superconducting phase. In addition, H(ex) decreases significantly with increasing temperature in the temperature range of 0.1-1 K. We discuss these results in the context of recent theories of generalized spin-dependent boundary conditions at a superconductor-ferromagnet interface.

  13. Study of the reduced magnetic field required for thermally assisted magnetization reversal

    Science.gov (United States)

    Firdausi, H. F. Y.; Utari; Purnama, B.

    2016-11-01

    The reduced magnetic field required for thermally magnetization reversal discussed in this paper. Study of thermally assisted magnetization reversal conduct by using micromagnetic simulation. The magnetic dot size of the simulation was 50 nm × 50 nm × 20 nm. The perpendicularly anisotropy constant was 2 × 106 erg/cm3. Initial condition was set single domain configuration. Then a sufficiently thermal pulse was used to get stochastic effect so that the magnetization along to the induce field direction for pico second duration. The results show that the reduced magnetic field mechanism seem to be temporary antiferromagnetic configuration before single domain configuration in alinging along to field direction. The same mechanims observed for modify of thickness dot particles. The require magnetic field of 145 Oe in thermally assisted magnetization reversal open a posibility for MRAM application.

  14. Experimental analysis of a TEM plane transmission line for DNA studies at 900 MHz EM fields

    International Nuclear Information System (INIS)

    Belloni, F; Doria, D; Lorusso, A; Nassisi, V; Velardi, L; Alifano, P; Monaco, C; Tala, A; Tredici, M; Raino, A

    2006-01-01

    A suitable plane transmission line was developed and its behaviour analysed at 900 MHz radiofrequency fields to study DNA mutability and the repair of micro-organisms. In this work, utilizing such a device, we investigated the behaviour of DNA mutability and repair of Escherichia coli strains. The transmission line was very simple and versatile in changing its characteristic resistance and field intensity by varying its sizes. In the absence of cell samples inside the transmission line, the relative modulation of the electric and/or magnetic field was ±31% with respect to the mean values, allowing the processing of more samples at different exposure fields in a single run. A slight decrease in spontaneous mutability to rifampicin-resistance of the E. coli JC411 strain was demonstrated in mismatch-repair proficient samples exposed to the radio-frequency fields during their growth on solid medium

  15. The combined field emission-spin trapping method for studying reactions of electrons in organic solutions

    International Nuclear Information System (INIS)

    Noda, Shoji; Ohta, Yasunari; Yoshida, Hiroshi

    1979-01-01

    The reactions of electrons injected by field emission into solutions have been investigated. Free radicals generated by the dissociative electron attachment to chlorinated solutes in benzene solutions were detected by the spin trapping-ESR method, using pentamethylnitrosobenzene as a spin trapping agent. Nondissociative electron attachment to styrene caused by the field emission was also evidenced by detecting the α-methylbenzyl radical generated secondarily from the styrene radical anion. The electrons field-emitted into the solutions are captured almost quantitatively by the electron scavenging solutes. The field emission method has been found to be useful for generating authentically free radicals and for studying the anionic reaction induced by electrons without interference of countercations and of any reaction intermediates from solvent molecules. As an example of the chemical utilization of the field emission technique, the ESR parameters of the spin adducts of several hydrocarbon radicals have been collected by this technique. (author)

  16. Field studies of Pan troglodytes reviewed and comprehensively mapped, focussing on Japan's contribution to cultural primatology.

    Science.gov (United States)

    McGrew, William C

    2017-01-01

    Field studies done over decades of wild chimpanzees in East, Central and West Africa have yielded impressive, cumulative findings in cultural primatology. Japanese primatologists have been involved in this advance from the outset, over a wide variety of topics. Here I review the origins and development of field studies of Pan troglodytes, then assess their progress based on analogy between cultural primatology and cultural anthropology, through four stages: natural history, ethnography, ethnology, and intuition. Then, I focus on six topics that continue to yield informative debate: technology, universals, nuanced variation, archaeology, applied primatology, and ecology. Finally, I offer a map of sites of field study of wild chimpanzees. It is clear that Japanese primatologists have made a significant contribution to East-West scientific exchange, especially at the field sites of Bossou and Mahale.

  17. Study of the Vertical Magnetic Field in Face-on Galaxies Using Faraday Tomography

    International Nuclear Information System (INIS)

    Ideguchi, Shinsuke; Ryu, Dongsu; Tashiro, Yuichi; Takahashi, Keitaro; Akahori, Takuya

    2017-01-01

    Faraday tomography allows astronomers to probe the distribution of the magnetic field along the line of sight (LOS), but that can be achieved only after the Faraday spectrum is interpreted. However, the interpretation is not straightforward, mainly because the Faraday spectrum is complicated due to a turbulent magnetic field; it ruins the one-to-one relation between the Faraday depth and the physical depth, and appears as many small-scale features in the Faraday spectrum. In this paper, by employing “simple toy models” for the magnetic field, we describe numerically as well as analytically the characteristic properties of the Faraday spectrum. We show that the Faraday spectrum along “multiple LOSs” can be used to extract the global properties of the magnetic field. Specifically, considering face-on spiral galaxies and modeling turbulent magnetic field as a random field with a single coherence length, we numerically calculate the Faraday spectrum along a number of LOSs and its shape-characterizing parameters, that is, the moments. When multiple LOSs cover a region of ≳(10 coherence length) 2 , the shape of the Faraday spectrum becomes smooth and the shape-characterizing parameters are well specified. With the Faraday spectrum constructed as a sum of Gaussian functions with different means and variances, we analytically show that the parameters are expressed in terms of the regular and turbulent components of the LOS magnetic field and the coherence length. We also consider the turbulent magnetic field modeled with a power-law spectrum, and study how the magnetic field is revealed in the Faraday spectrum. Our work suggests a way to obtain information on the magnetic field from a Faraday tomography study.

  18. Simulation study of solar plasma eruptions caused by interactions between emerging flux and coronal arcade fields

    International Nuclear Information System (INIS)

    Kaneko, Takafumi; Yokoyama, Takaaki

    2014-01-01

    We investigate the triggering mechanisms of plasma eruptions in the solar atmosphere due to interactions between emerging flux and coronal arcade fields by using two-dimensional MHD simulations. We perform parameter surveys with respect to arcade field height, magnetic field strength, and emerging flux location. Our results show that two possible mechanisms exist, and which mechanism is dominant depends mostly on emerging flux location. One mechanism appears when the location of emerging flux is close to the polarity inversion line (PIL) of an arcade field. This mechanism requires reconnection between the emerging flux and the arcade field, as pointed out by previous studies. The other mechanism appears when the location of emerging flux is around the edge of an arcade field. This mechanism does not require reconnection between the emerging flux and the arcade field but does demand reconnection in the arcade field above the PIL. Furthermore, we found that the eruptive condition for this mechanism can be represented by a simple formula.

  19. Runoff of pesticides from rice fields in the Ile de Camargue (Rhone river delta, France): Field study and modeling

    International Nuclear Information System (INIS)

    Comoretto, Laetitia; Arfib, Bruno; Talva, Romain; Chauvelon, Philippe; Pichaud, Marc; Chiron, Serge; Hoehener, Patrick

    2008-01-01

    A field study on the runoff of pesticides was conducted during the cultivation period in 2004 on a hydraulically isolated rice farm of 120 ha surface with one central water outlet. Four pesticides were studied: Alphamethrin, MCPA, Oxadiazon, and Pretilachlor. Alphamethrin concentrations in runoff never exceeded 0.001 μg L -1 . The three other pesticides were found in concentrations between 5.2 and 28.2 μg L -1 in the runoff water shortly after the application and decreased thereafter. The data for MCPA compared reasonably well with predictions by an analytical runoff model, accounting for volatilization, degradation, leaching to groundwater, and sorption to soil. The runoff model estimated that runoff accounted for as much as 18-42% of mass loss for MCPA. Less runoff is observed and predicted for Oxadiazon and Pretilachlor. It was concluded that runoff from rice paddies carries important loads of dissolved pesticides to the wetlands in the Ile de Camargue, and that the model can be used to predict this runoff. - Runoff of dissolved pesticides was measured on a rice farm in the Camargue (France) and modeled with an analytical model

  20. Toward a model for field-testing patient decision-support technologies: a qualitative field-testing study.

    NARCIS (Netherlands)

    Evans, R.; Elwyn, G.; Edwards, A.; Watson, E.; Austoker, J.; Grol, R.P.T.M.

    2007-01-01

    BACKGROUND: Field-testing is a quality assurance criterion in the development of patient decision-support technologies (PDSTs), as identified in the consensus statement of the International Patient Decision Aids Standards Collaboration. We incorporated field-testing into the development of a

  1. Gravimetric monitoring of the first field-wide steam injection in a fractured carbonate field in Oman - A feasibility study

    NARCIS (Netherlands)

    Glegola, M.; Ditmar, P.; Vossepoel, F.; Arts, R.; Al-Kindy, F.; Klees, R.

    2015-01-01

    Gas-Oil Gravity Drainage is to be enhanced by steam injection in a highly fractured, low permeability carbonate field in Oman. Following a successful pilot, field-wide steam injection is being implemented, first of this type in the world. A dedicated monitoring program has been designed to track

  2. Reservoir Simulation on the Cerro Prieto Geothermal Field: A Continuing Study

    Energy Technology Data Exchange (ETDEWEB)

    Castaneda, M.; Marquez, R.; Arellano, V.; Esquer, C.A.

    1983-12-15

    The Cerro Prieto geothermal field is a liquid-dominated geothermal reservoir of complex geological and hydrological structure. It is located at the southern end of the Salton-Mexicali trough which includes other geothermal anomalies as Heber and East Mesa. Although in 1973, the initial power plant installed capacity was 75 MW of electrical power, this amount increased to 180 MW in 1981 as field development continued. It is expected to have a generating capacity of 620 MW by the end of 1985, when two new plants will be completely in operation. Questions about field deliverability, reservoir life and ultimate recovery related to planned installations are being presently asked. Numerical modeling studies can give very valuable answers to these questions, even at the early stages in the development of a field. An effort to simulate the Cerro Prieto geothermal reservoir has been undergoing for almost two years. A joint project among Comision Federal de Electricidad (CFE), Instituto de Investigaciones Electricas (IIE) and Intercomp of Houstin, Texas, was created to perform reservoir engineering and simulation studies on this field. The final project objective is tosimulate the behavior of the old field region when production from additional wells located in the undeveloped field zones will be used for feeding the new power plants.

  3. Numerical Study of Flow Motion and Patterns Driven by a Rotating Permanent Helical Magnetic Field

    Science.gov (United States)

    Yang, Wenzhi; Wang, Xiaodong; Wang, Bo; Baltaretu, Florin; Etay, Jacqueline; Fautrelle, Yves

    2016-10-01

    Liquid metal magnetohydrodynamic flow driven by a rotating permanent helical magnetic field in a cylindrical container is numerically studied. A three-dimensional numerical simulation provides insight into the visualization of the physical fields, including the magnetic field, the Lorentz force density, and the flow structures, especially the flow patterns in the meridional plane. Because the screen parameter is sufficiently small, the model is decoupled into electromagnetic and hydrodynamic components. Two flow patterns in the meridional plane, i.e., the global flow and the secondary flow, are discovered and the impact of several system parameters on their transition is investigated. Finally, a verifying model is used for comparison with the previous experiment.

  4. Study and realization of a power circuit of a superconducting dipole generator of a magnetic field

    International Nuclear Information System (INIS)

    Rouanet, E.

    1993-01-01

    The project of experimental reactor building on controlled fusion (I.T.E.R) needed the development of a superconducting cable made of niobium-tin. Tested with a current of fifty kilo amperes under a twelve tesla constant field, this cable has to be tested under a variable field. The installation of the power circuit of the dipole field generator, consisted to the study and realization of the four following points: an important power cable; a tension protection organ of the dipole, under a seventeen milli Henrys inductance and four kilo amperes; a current regulating system given by the generator; a complete pilot system of the test station

  5. Neutron scattering study of the field-induced soliton lattice in CuGeO3

    DEFF Research Database (Denmark)

    Rønnow, H.M.; Enderle, M.; McMorrow, D.F.

    2000-01-01

    CuGeO3 undergoes a transition from a spin-Peierls phase to an incommensurate phase at a critical field of H-c approximate to 12.5 T. In the high-field phase a lattice of solitons forms, with both structural and magnetic components, and these have been studied using neutron scattering techniques....... Our results provide direct evidence for a long-ranged magnetic soliton structure which has both staggered and uniform magnetizations with amplitudes that are broadly in accord with theoretical estimates. The magnetic soliton width Gamma(m) and the field dependence of the incommensurability delta k...

  6. Study of luminous phenomena observed on contaminated metallic surfaces submitted to high RF fields

    International Nuclear Information System (INIS)

    Maissa, S.; Junquera, T.; Fouaidy, M.; Le Goff, A.; Bonin, B.; Luong, M.; Safa, H.; Tan, J.

    1995-01-01

    The RF field emission from a sample subjected to high RF fields in a copper cavity has been investigated. The study is focused on the luminous emissions occurring on the RF surface simultaneously with the electron emission. The optical apparatus attached to the cavity permits to observe the evolution of the emitters and the direct effects of the surface conditioning. Also, the parameters of the emitted radiation (intensity, glowing duration, spectral distribution) may provide additional informations on the field emission phenomena. Some results concerning samples intentionally contaminated with particles (metallic or dielectric) are presented. (K.A.)

  7. Magnetic and magneto-optic study of antiferromagnets in very high fields (500 kOe)

    International Nuclear Information System (INIS)

    Gunzbourg, Jacques de

    1970-01-01

    A description is given of devices which have been developed for pulsed field magnetization measurements between 1.6 deg. K and 300 deg. K and for static and pulsed field Faraday rotation measurements between 6 deg. K. and 300 deg. K throughout the whole visible spectra. A comparative study was made of the magnetic and magneto-optic properties of a metamagnetic substance, NiCl 2 , and a systematic analysis was made of the non-linearity of its magnetization with respect to the field (before saturation); this phenomena is observed with most antiferromagnetic materials. (author) [fr

  8. Evolving Curricular Models in Culinary Arts: An Instrumental Case Study of a Technical Field

    Science.gov (United States)

    Cossio, Allison

    2016-01-01

    The purpose of this research study was to examine how chefs and other individuals in the food industry understood the field of culinary arts. This study used an instrumental case study with purposeful sampling of multiple cases. Through a series of open-ended interviews using snowball-sampling strategy that concluded with 45 participants sharing…

  9. Feasibility of a cohort study on health risks caused by occupational exposure to radiofrequency electromagnetic fields

    DEFF Research Database (Denmark)

    Breckenkamp, Jürgen; Berg-Beckhoff, Gabriele; Münster, Eva

    2009-01-01

    BACKGROUND: The aim of this study was to examine the feasibility of performing a cohort study on health risks from occupational exposure to radiofrequency electromagnetic fields (RF-EMF) in Germany. METHODS: A set of criteria was developed to evaluate the feasibility of such a cohort study...

  10. Experimental study of directionally solidified ferromagnetic shape memory alloy under multi-field coupling

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Yuping, E-mail: zhuyuping@126.com [Institute of Geophysics, China Earthquake Administration, Beijing 100081 (China); Chen, Tao; Teng, Yao [Faculty of Civil Engineering and Mechanics, Jiangsu University, Zhenjiang 212013 (China); Liu, Bingfei [Airport College, Civil Aviation University of China, Tianjin 300300 (China); Xue, Lijun [Tianjin Key Laboratory of the Design and Intelligent Control of the Advanced Mechatronical System, School of Mechanical Engineering, Tianjin University of Technology, Tianjin 300384 (China)

    2016-11-01

    Directionally solidified, polycrystalline Ni–Mn–Ga is studied in this paper. The polycrystalline Ni–Mn–Ga samples were cut at different angles to solidification direction. The magnetic field induced strain under constant stress and the temperature-induced strain under constant magnetic field during the loading–unloading cycle were measured. The experimental results show that the mechanical behavior during the loading–unloading cycle of the material is nonlinear and anisotropic. Based on the experimental results, the effects of multi-field coupling factors, such as stress, magnetic field, temperature and cutting angle on the mechanical behaviors were analyzed. Some useful conclusions were obtained, which will provide guidance for practical applications. - Highlights: • The magnetic-induced strains in different directions are tested. • The temperature-induced strains in different directions are tested. • The effects of coupling factors on directional solidification samples are studied.

  11. Experimental study of directionally solidified ferromagnetic shape memory alloy under multi-field coupling

    International Nuclear Information System (INIS)

    Zhu, Yuping; Chen, Tao; Teng, Yao; Liu, Bingfei; Xue, Lijun

    2016-01-01

    Directionally solidified, polycrystalline Ni–Mn–Ga is studied in this paper. The polycrystalline Ni–Mn–Ga samples were cut at different angles to solidification direction. The magnetic field induced strain under constant stress and the temperature-induced strain under constant magnetic field during the loading–unloading cycle were measured. The experimental results show that the mechanical behavior during the loading–unloading cycle of the material is nonlinear and anisotropic. Based on the experimental results, the effects of multi-field coupling factors, such as stress, magnetic field, temperature and cutting angle on the mechanical behaviors were analyzed. Some useful conclusions were obtained, which will provide guidance for practical applications. - Highlights: • The magnetic-induced strains in different directions are tested. • The temperature-induced strains in different directions are tested. • The effects of coupling factors on directional solidification samples are studied.

  12. A study on some optical illusions based upon the theory of inducing field.

    Science.gov (United States)

    Ge, Sheng; Saito, Takashi; Wu, Jing-Long; Iramina, K

    2006-01-01

    The study of optical illusion is an important method to elucidate the mechanism of visual perception. However, many details about the cause of optical illusions are still unclear. In this research, based on the characteristic of the physiological structure of the retina, we proposed an on-center receptive field model of the retina. Using this model, we simulated the distributions of the inducing field of some visual stimulus. Comparing to the past studies' results, the validity of the proposed model was proofed. Furthermore, we simulated the distributions of the inducing field of some typical illusions. The simulation results can explain these illusion phenomenon rationally. Therefore, it suggested that some of illusions are probably engendered by the distributions of the inducing field in the retina which generated by the illusions stimuli. The practicality of the proposed model was also verified.

  13. [Comparative study on the historical evolution of field surgery between China and Russia].

    Science.gov (United States)

    Li, Yong; Luo, Chang-kun; Xiao, Nan

    2010-03-01

    Russian field surgery with its long history and distinctive characteristics has accumulated great experience in the long-time practice of warfare. Chinese field surgery was established and developed on the basis of studying from the Russian model, which opened up new areas of traffic medicine, molecular traumatology and assessment of biological effects on weapon destruction and carried out in-depth research on wound ballistics, blast injury, burns and combined injury etc. through decades of construction with continuous development and innovation, and a series of major achievements have been made in these fields. By making comparative study on the historical evolution, structure system, characteristics of campaigns and development of society between Chinese and Russian field surgery, it can be found that there are great gaps between them and we should strengthen the research for more rapid development.

  14. The Momotombo Geothermal Field, Nicaragua: Exploration and development case history study

    Energy Technology Data Exchange (ETDEWEB)

    None

    1982-07-01

    This case history discusses the exploration methods used at the Momotombo Geothermal Field in western Nicaragua, and evaluates their contributions to the development of the geothermal field models. Subsequent reservoir engineering has not been synthesized or evaluated. A geothermal exploration program was started in Nicaragua in 1966 to discover and delineate potential geothermal reservoirs in western Nicaragua. Exploration began at the Momotombo field in 1970 using geological, geochemical, and geophysical methods. A regional study of thermal manifestations was undertaken and the area on the southern flank of Volcan Momotombo was chosen for more detailed investigation. Subsequent exploration by various consultants produced a number of geotechnical reports on the geology, geophysics, and geochemistry of the field as well as describing production well drilling. Geological investigations at Momotombo included photogeology, field mapping, binocular microscope examination of cuttings, and drillhole correlations. Among the geophysical techniques used to investigate the field sub-structure were: Schlumberger and electromagnetic soundings, dipole mapping and audio-magnetotelluric surveys, gravity and magnetic measurements, frequency domain soundings, self-potential surveys, and subsurface temperature determinations. The geochemical program analyzed the thermal fluids of the surface and in the wells. This report presents the description and results of exploration methods used during the investigative stages of the Momotombo Geothermal Field. A conceptual model of the geothermal field was drawn from the information available at each exploration phase. The exploration methods have been evaluated with respect to their contributions to the understanding of the field and their utilization in planning further development. Our principal finding is that data developed at each stage were not sufficiently integrated to guide further work at the field, causing inefficient use of

  15. Wide-field monitoring strategy for the study of fast optical transients

    Science.gov (United States)

    Beskin, Grigory; Bondar, Sergey; Karpov, Sergey; Guarnieri, Adriano; Bartolini, Corrado; Greco, Giuseppe; Piccioni, Adalberto

    2010-10-01

    We discuss the strategy of search for fast optical transients accompanying gamma-ray bursts by means of continuous monitoring of wide sky fields with high temporal resolution. We describe the design, performance and results of our cameras, FAVOR and TORTORA. Also we discuss the perspectives of this strategy and possible design of next-generation equipment for wide-field monitoring which will be able to detect optical transients and to study their color and polarization properties with high time resolution.

  16. Field evaluation of a tensiometer data acquisition system for hydrologic studies of waste disposal site design

    International Nuclear Information System (INIS)

    Nyhan, J.W.; Drennon, B.J.; Gaylor, R.M.

    1987-01-01

    Commercially available differential pressure transducers, tensiometers and a data acquisition system were combined to study soil water tension changes with time within two trench cap designs used for the shallow land burial of waste materials. Apparent diurnal variations in soil water tension measured with this system are evaluated relative to field variations in temperature, atmospheric pressure and soil water content. Ongoing research is described which should improve the reliability of future soil water tension data collected in the field. 10 refs., 5 figs

  17. Methods for studying and criteria for evaluating the biological effects of electric fields of industrial frequency

    Energy Technology Data Exchange (ETDEWEB)

    Savin, B.M.; Shandala, M.G.; Nikonova, K.V.; Morozov, Yu.A.

    1978-10-01

    Data are reviewed from a number of USSR research studies on the biological effects of electric power transmission lines of 1150 Kv and above. Effects on man, plants, animals, and terrestrial ecosystems are reported. Existing health standards in the USSR for the exposure of personnel working in electric fields are included. It is concluded that high-voltage electric fields have a harmful effect on man and his environment.

  18. Electron spin resonance study of the demagnetization fields of the ferromagnetic and paramagnetic films

    Directory of Open Access Journals (Sweden)

    I.I. Gimazov, Yu.I. Talanov

    2015-12-01

    Full Text Available The results of the electron spin resonance study of the La1-xCaxMnO3 manganite and the diphenyl-picrylhydrazyl thin films for the magnetic field parallel and perpendicular to plane of the films are presented. The temperature dependence of the demagnetizing field is obtained. The parameters of the Curie-Weiss law are estimated for the paramagnetic thin film.

  19. A statistical study of intense electric fields at 4−7 RE geocentric distance using Cluster

    Directory of Open Access Journals (Sweden)

    T. Johansson

    2005-10-01

    Full Text Available Intense high-latitude electric fields (>150 mV/m mapped to ionospheric altitude at 4–7 RE geocentric distance have been investigated in a statistical study, using data from the Cluster satellites. The orbit of the Cluster satellites limits the data collection at these altitudes to high latitudes, including the poleward part of the auroral oval. The occurrence and distribution of the selected events have been used to characterize the intense electric fields and to investigate their dependance on parameters such as MLT, CGLat, altitude, and also Kp. Peaks in the local time distribution are found in the evening to morning sectors but also in the noon sector, corresponding to cusp events. The electric field intensities decrease with increasing latitude in the region investigated (above 60 CGLat. A dependence on geomagnetic activity is indicated since the probability of finding an event increases up to Kp=5–6. The scales sizes are in the range up to 10 km (mapped to ionospheric altitude with a maximum around 4–5km, consistent with earlier findings at lower altitudes and Cluster event studies. The magnitudes of the electric fields are inversely proportional to the scale sizes. The type of electric field structure (convergent or divergent is consistent with the FAC direction for a subset of events with electric field intensities in the range 500–1000 mV/m and with clear bipolar signatures. The FAC directions are also consistent with the Region 1 and NBZ current systems, the latter of which prevail only during northward IMF conditions. For scale sizes less than 2 km the majority of the events were divergent electric field structures. Both converging and diverging electric fields were found throughout the investigated altitude range (4–7 RE geocentric distance. Keywords. Magnetospheric physics (Electric fields; Auroral phenomena; Magnetosphere-ionosphere interactions

  20. Field experience in science for fifth grade students---a mixed methods study of learning environments

    Science.gov (United States)

    Patterson, Barbara E.

    The purpose of this research is to compare students' perceptions of the learning environment in a traditional science classroom and a field study classroom. This mixed methods study used a sequential explanatory design. Phase one was the quantitative phase using two survey tools. A modified version of the "What is happening in this Classroom Survey" (WIHIC) (Fraser et al., 1996) and the "Test of Science Related Attitudes" (TOSRA) (Fraser, 1982) was administered to 60 fifth grade students from one school. Data was then disaggregated by socioeconomic class and ethnicity. Results from Phase one showed that students prefer the classroom for investigation and prefer the field environment for enjoyment of science. Differences in ethnicity and class were small but Hispanic students prefer the field for investigation and equity. Students that are low socio-economic class rank cooperation in the field higher than the classroom and students that do not qualify for free or reduced lunch prefer the field environment for enjoyment of science. Finally, there are strong correlations for the variables of cooperation, investigation, equity and enjoyment of science in both the classroom and the field environment. Questions raised from the analysis of the survey data were further explored through qualitative data collection methods in phase two. Student responses to three questions were coded using template analysis to provide answers to the "how and why" field experience effects students' attitudes toward science. Three themes emerged from the coding of the results. These results showed that students are physically engaged, develop a sense of place and learn skills in the field that reinforce concepts learned in the classroom. This information will help teachers in developing quality and meaningful experiences for all students. "Closing the gaps among minority groups while improving achievement of all students constitutes the dual goals of education in the nation" (Lee et al., 2004

  1. Studies of Westward Electrojets and Field-Aligned Currents in the Magnetotail During Substorms: Implications for Magnetic Field Models

    Science.gov (United States)

    Spence, Harlan E.

    1996-01-01

    This section outlines those tasks undertaken in the final year that contribute integrally to the overarching project goals. Fast, during the final year, it is important to note that the project benefited greatly with the addition of a Boston University graduate student, Ms. Karen Hirsch. Jointly, we made substantial progress on the development of and improvements to magnetotail magnetic field and plasma models. The ultimate aim of this specific task was to assess critically the utility of such models for mapping low-altitude phenomena into the magnetotail (and vice-versa). The bulk of this effort centered around the finite-width- magnetotail convection model developed by and described by Spence and Kivelson (J. Geophys. Res., 98, 15,487, 1993). This analytic, theoretical model specifies the bulk plasma characteristics of the magnetotail plasma sheet (number density, temperature, pressure) across the full width of the tail from the inner edge of the plasma sheet to lunar distances. Model outputs are specified by boundary conditions of the source particle populations as well as the magnetic and electric field configuration. During the reporting period, we modified this code such that it can be interfaced with the auroral particle precipitation model developed by Dr. Terry Onsager. Together, our models provide a simple analytic specification of the equatorial distribution of fields and plasma along with their low-altitude consequences. Specifically, we have built a simple, yet powerful tool which allows us to indirectly 'map' auroral precipitation signatures (VDIS, inverted-V's, etc.) measured by polar orbiting spacecraft in the ionosphere, to the magnetospheric equatorial plane. The combined models allow us to associate latitudinal gradients measured in the ion energy fluxes at low-altitudes with the large-scale pressure gradients in the equatorial plane. Given this global, quasi-static association, we can then make fairly strong statements regarding the location of

  2. Study on magnetic field mapping within cylindrical center volume of general magnet

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Li; Lee, Sang Jin [Uiduk University, Gyeongju (Korea, Republic of)

    2016-06-15

    For the magnetic field analysis or design, it is important to know the behavior of the magnetic field in an interesting space. Magnetic field mapping becomes a useful tool for the study of magnetic field. In this paper, a numerical way for mapping the magnetic field within the cylindrical center volume of magnet is presented, based on the solution of the Laplace's equation in the cylindrical coordinate system. The expression of the magnetic field can be obtained by the magnetic flux density, which measured in the mapped volume. According to the form of the expression, the measurement points are arranged with the parallel cylindrical line (PCL) method. As example, the magnetic flux density generated by an electron cyclotron resonance ion source (ECRIS) magnet and a quadrupole magnet were mapped using the PCL method, respectively. The mapping results show the PCL arrangement method is feasible and convenience to map the magnetic field within a cylindrical center volume generated by the general magnet.

  3. A test on reactive force fields for the study of silica dimerization reactions

    Energy Technology Data Exchange (ETDEWEB)

    Moqadam, Mahmoud; Riccardi, Enrico; Trinh, Thuat T.; Åstrand, Per-Olof; Erp, Titus S. van, E-mail: titus.van.erp@ntnu.no [Department of Chemistry, Norwegian University of Science and Technology (NTNU), Høgskoleringen 5, Realfagbygget D3-117, 7491 Trondheim (Norway)

    2015-11-14

    We studied silica dimerization reactions in the gas and aqueous phase by density functional theory (DFT) and reactive force fields based on two parameterizations of ReaxFF. For each method (both ReaxFF force fields and DFT), we performed constrained geometry optimizations, which were subsequently evaluated in single point energy calculations using the other two methods. Standard fitting procedures typically compare the force field energies and geometries with those from quantum mechanical data after a geometry optimization. The initial configurations for the force field optimization are usually the minimum energy structures of the ab initio database. Hence, the ab initio method dictates which structures are being examined and force field parameters are being adjusted in order to minimize the differences with the ab initio data. As a result, this approach will not exclude the possibility that the force field predicts stable geometries or low transition states which are realistically very high in energy and, therefore, never considered by the ab initio method. Our analysis reveals the existence of such unphysical geometries even at unreactive conditions where the distance between the reactants is large. To test the effect of these discrepancies, we launched molecular dynamics simulations using DFT and ReaxFF and observed spurious reactions for both ReaxFF force fields. Our results suggest that the standard procedures for parameter fitting need to be improved by a mutual comparative method.

  4. Simulational studies of epitaxial semiconductor superlattices: Quantum dynamical phenomena in ac and dc electric fields

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, Joseph [Iowa State Univ., Ames, IA (United States)

    1997-10-08

    Using high-accuracy numerical methods the author investigates the dynamics of independent electrons in both ideal and realistic superlattices subject to arbitrary ac and/or dc electric fields. For a variety of superlattice potentials, optically excited initial wave packets, and combinations of ac and dc electric fields, he numerically solves the time-dependent Schroedinger equation. In the case of ideal periodic superlattice potentials, he investigates a long list of dynamical phenomena involving multiple miniband transitions and time-dependent electric fields. These include acceleration effects associated with interminiband transitions in strong fields, Zener resonances between minibands, dynamic localization with ac fields, increased single-miniband transport with an auxiliary resonant ac field, and enhanced or suppressed interminiband probability exchange using an auxiliary ac field. For all of the cases studied, the resulting time-dependent wave function is analyzed by projecting the data onto convenient orthonormal bases. This allows a detailed comparison with approximately analytic treatments. In an effort to explain the rapid decay of experimentally measured Bloch oscillation (BO) signals the author incorporates a one-dimensional representation of interface roughness (IR) into their superlattice potential. He shows that as a result of IR, the electron dynamics can be characterized in terms of many discrete, incommensurate frequencies near the Block frequency. Chapters 2, 3, 4 and 5 have been removed from this report and will be processed separately.

  5. Site Study Plan for Acoustics, Deaf Smith County Site, Texas: Environmental Field Program: Preliminary draft

    International Nuclear Information System (INIS)

    1987-06-01

    The Acoustics site study plan describes a field program which characterizes existing sound levels, determines the area's sound propagation characteristics, and monitors the project-related sound emissions. The plan describes for each study: the need for the study, study design, data management and use, schedule, and quality assurance requirements. These studies will provide data needed to satisfy requirements contained in, or derived from, the Salt Repository Requirements Document. 37 refs., 9 figs., 3 tabs

  6. Competition Between Fusarium pseudograminearum and Cochliobolus sativus Observed in Field and Greenhouse Studies.

    Science.gov (United States)

    Troth, Erin E Gunnink; Johnston, Jeffrey A; Dyer, Alan T

    2018-02-01

    Among root pathogens, one of the most documented antagonisms is the suppression of Cochliobolus sativus by Fusarium (roseum) species. Unfortunately, previous studies involved single isolates of each pathogen and thus, provided no indication of the spectrum of responses that occur across the respective species. To investigate the variability in interactions between Cochliobolus sativus and Fusarium pseudograminearum, field and greenhouse trials were conducted that included monitoring of spring wheat plant health and monitoring of pathogen populations via quantitative real-time polymerase chain reaction. The interactions between two isolates of C. sativus and four isolates of F. pseudograminearum were explored in three geographically distinct wheat fields. To complement field trials and to limit potentially confounding environmental variables that are often associated with field studies, greenhouse trials were performed that investigated the interactions among and between three isolates of C. sativus and four isolates of F. pseudograminearum. Across field locations, C. sativus isolate Cs2344 consistently and significantly reduced Fusarium populations by an average of 20.1%. Similarly, F. pseudograminearum isolate Fp2228 consistently and significantly reduced C. sativus field populations by an average of 30.9%. No interaction was detected in the field between pathogen species with regards to disease or crop losses. Greenhouse results confirmed a powerful (>99%), broadly effective suppression of Fusarium populations by isolate Cs2344. Among greenhouse trials, additional isolate-isolate interactions were observed affecting Fusarium populations. Due to lower C. sativus population sizes in greenhouse trials, significant Fusarium suppression of C. sativus was only detected in one isolate-isolate interaction. This study is the first to demonstrate suppression of Fusarium spp. by C. sativus in field and greenhouse settings. These findings also reveal a complex competitive

  7. Study of field-aligned current (FAC), interplanetary electric field component (Ey), interplanetary magnetic field component (Bz), and northward (x) and eastward (y) components of geomagnetic field during supersubstorm

    Science.gov (United States)

    Adhikari, Binod; Dahal, Subodh; Chapagain, Narayan P.

    2017-05-01

    A dominant process by which energy and momentum are transported from the magnetosphere to the ionosphere is known as field-aligned current (FAC). It is enhanced during magnetic reconnection and explosive energy release at a substorm. In this paper, we studied FAC, interplanetary electric field component (Ey), interplanetary magnetic field component (Bz), and northward (x) and eastward (y) components of geomagnetic field during three events of supersubstorm occurred on 24 November 2001, 21 January 2005, and 24 August 2005. Large-scale FAC, supposed to be produced during supersubstorm (SSS), has potentiality to cause blackout on Earth. We examined temporal variations of the x and y components of high-latitude geomagnetic field during SSS, which is attributed to the FACs. We shall report the characteristics of high-latitude northward and eastward components of geomagnetic field variation during the growth phase of SSS by the implementation of discrete wavelet transform (DWT) and cross-correlation analysis. Among three examples of SSS events, the highest peak value of FAC was estimated to be 19 μAm-2. This is shore up with the prediction made by Parks (1991) and Stasiewicz et al. (1998) that the FACs may vary from a few tens to several hundred μAm-2. Although this peak value of FACs for SSS event is much higher than the average FACs associated with regular substorms or magnetic storms, it is expedient and can be expect for SSS events which might be due to very high density solar wind plasma parcels (PPs) triggering the SSS events. In all events, during growth phase, the FAC increases to extremely high level and the geomagnetic northward component decreases to extremely low level. This represents a strong positive correlation between FAC and geomagnetic northward component. The DWT analysis accounts that the highest amplitude of the wavelet coefficients indicates singularities present in FAC during SSS event. But the amplitude of squared wavelet coefficient is found

  8. Theoretical study of in-plane response of magnetic field sensor to magnetic beads in an in-plane homogeneous field

    DEFF Research Database (Denmark)

    Damsgaard, Christian Danvad; Hansen, Mikkel Fougt

    2008-01-01

    We present a systematic theoretical study of the average in-plane magnetic field on square and rectangular magnetic field sensors from a single magnetic bead and a monolayer of magnetic beads magnetized by an in-plane externally applied homogeneous magnetic field. General theoretical expressions...... are derived such that the sensor response and its dependence on the sensor size, spacer layer thickness, bead diameter, and bead susceptibility can easily be evaluated. The average magnetic field from a single bead close to the sensor shows a strong dependence on the position of the bead and a change of sign...... when the bead passes the edge of the sensor in the direction of the applied field. Analytical approximations are derived for the average field from a homogeneous monolayer of beads for beads much smaller than the sensor dimension and for a bead size chosen to minimize the position sensitivity...

  9. Study of Landau spectrum for a two-dimensional random magnetic field

    International Nuclear Information System (INIS)

    Furtlehner, C.

    1997-01-01

    This thesis deals with the two-dimensional problem of a charged particle coupled to a random magnetic field. Various situations are considered, according to the relative importance of the mean value of field and random component. The last one is conceived as a distribution of magnetic impurities (punctual vortex), having various statistical properties (local or non-local correlations, Poisson distribution, etc). The study of this system has led to two distinct situations: - the case of the charged particle feeling the influence of mean field that manifests its presence in the spectrum of broadened Landau levels; - the disordered situation in which the spectrum can be distinguished from the free one only by a low energy Lifshits behaviour. Additional properties are occurring in the limit of 'strong' mean field, namely a non-conventional low energy behaviour (in contrast to Lifshits behaviour) which was interpreted in terms of localized states. (author)

  10. Experimental study of directionally solidified ferromagnetic shape memory alloy under multi-field coupling

    Science.gov (United States)

    Zhu, Yuping; Chen, Tao; Teng, Yao; Liu, Bingfei; Xue, Lijun

    2016-11-01

    Directionally solidified, polycrystalline Ni-Mn-Ga is studied in this paper. The polycrystalline Ni-Mn-Ga samples were cut at different angles to solidification direction. The magnetic field induced strain under constant stress and the temperature-induced strain under constant magnetic field during the loading-unloading cycle were measured. The experimental results show that the mechanical behavior during the loading-unloading cycle of the material is nonlinear and anisotropic. Based on the experimental results, the effects of multi-field coupling factors, such as stress, magnetic field, temperature and cutting angle on the mechanical behaviors were analyzed. Some useful conclusions were obtained, which will provide guidance for practical applications.

  11. A theoretical study of the dynamics of paramagnetic superrotors in external magnetic fields

    International Nuclear Information System (INIS)

    Floß, Johannes

    2015-01-01

    We present a detailed theoretical study of oxygen molecules in high rotational states (molecular superrotors) interacting with an external magnetic field. The system shows rich dynamics, ranging from a spin-selective splitting of the angular distribution over molecular alignment to an inversion of the rotational direction. We find that the observed magneto-rotational effects are due to a spin-mediated precession of the orbital angular momentum around the magnetic field. Analytical expressions for the precession frequency in the limits of weak and strong magnetic fields are derived and used to support the proposed mechanism. In addition, we provide the procedure for a numerical treatment of oxygen superrotors in an external magnetic field. (paper)

  12. Field studies of submerged-diffuser thermal plumes with comparisons to predictive model results

    International Nuclear Information System (INIS)

    Frigo, A.A.; Paddock, R.A.; Ditmars, J.D.

    1976-01-01

    Thermal plumes from submerged discharges of cooling water from two power plants on Lake Michigan were studied. The system for the acquisition of water temperatures and ambient conditions permitted the three-dimensional structure of the plumes to be determined. The Zion Nuclear Power Station has two submerged discharge structures separated by only 94 m. Under conditions of flow from both structures, interaction between the two plumes resulted in larger thermal fields than would be predicted by the superposition of single non-interacting plumes. Maximum temperatures in the near-field region of the plume compared favorably with mathematical model predictions. A comparison of physical-model predictions for the plume at the D. C. Cook Nuclear Plant with prototype measurements indicated good agreement in the near-field region, but differences in the far-field occurred as similitude was not preserved there

  13. The dynamic ergodic divertor in TEXTOR-A novel tool for studying magnetic perturbation field effects

    International Nuclear Information System (INIS)

    Neubauer, O.; Czymek, G.; Finken, K.H.; Giesen, B.; Huettemann, P.W.; Lambertz, H.T.; Schruff, J.

    2005-01-01

    Recently TEXTOR has been upgraded by the installation of the dynamic ergodic divertor (DED). The purpose of the DED is to influence transport parameters in plasma edge and core and to study the resulting effects on heat exhaust, edge cooling, impurity screening, plasma confinement and stability. Alternatively, the DED creates static or rotating multipolar helical magnetic perturbation fields of different mode patterns. A set of 16 helical coils has been installed on the inboard high-field side of the vacuum vessel. Rotating fields of up to 10 kHz can be generated. A novel coil design has been developed which fulfills the various mechanical, electrical, high frequency, thermal, and vacuum requirements. In addition to the various technical aspects of the DED design, implementation and commissioning, highlights of recent experiments will be presented. In particular the impact of the perturbation field on MHD stability and plasma rotation will be addressed

  14. Magnetic field effects on geminate reactions. Study of anthraquinone - hydrogen donors systems

    International Nuclear Information System (INIS)

    Vidal, Marie-Helene

    1987-01-01

    This study is devoted to magnetic field effects on chemical reactions which involve a radical pair with correlated spins (radical in a 'cage'). In the first part, the radical pair theory is described: mechanisms of singlet-triplet mixing, the different interactions inside the pair and a quantum mechanical treatment of the radical pair. The details of the experimental method (nanosecond laser flash photolysis) are reported in the second part. In the third part are shown experimental results obtained on Anthraquinone (AQ) - Hydrogen donors systems: - There is no magnetic field effect in homogeneous solution even at a high viscosity. The absorption spectra of the different reaction intermediates are obtained. - However a magnetic field effect is put forward when AQ is introduced in SDS micelles which are hydrogen donors. The absorption spectrum of the AQH · . semi-quinone radical in 'cage' is shown and a mechanism is proposed for its disappearance to generate the AQH-S and AQH 2 species. - The addition of 9, 10 Dihydroanthracene (DH2) inside the micelle near AQ induces an increase of the magnetic field effect by creation of (AQH · . - DH · . ) pairs which diffuse slowly. - Fixed radical pairs in a protein matrix were studied in reaction centers of photosynthetic bacteria: in that case, the half effect field is shifted to low fields when compared to the previously described systems. (author) [fr

  15. IMS advances in studies of field-aligned currents and their related electrodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Kamide, Y.

    1985-12-01

    During the IMS period, there have been major advances in four areas regarding field-aligned currents which directly reflect the electrical coupling between the magnetosphere and the ionosphere. First, the spatial distribution of the large-scale field-aligned currents (in particular, their average configuration) has been extensively examined with respect to IMF (interplanetary magnetic field) parameters. The role of the field-aligned currents in the dayside polar cap including their IMF B/sub y/ dependence and seasonal dependence has been cleared to some extent. It remains to be answered, however, if the substorm pattern differs uniquely from the average disturbed pattern. Second, the three-dimensional current system has been studied by using satellite and ground-based, as well as radar, measurements. The nature of the substorm current system, which changes quite dynamically depending upon the different substorm phases as well as upon different auroral forms, has been more clearly defined. A third major advance has been in the efforts to find the relative location of the field-aligned currents to various ionospheric parameters, such as electric fields, conductivities, and discrete and diffuse auroras. Finally, numerical simulations of assumptions have increasingly become a powerful tool for the study of the dynamics of the magnetosphere-ionosphere system. It appears that the large-scale characteristics of the system under steady state conditions are known in the sense that the measured key parameters are mutually consistent for average data sets.

  16. Coherence of heart rate variability and local physical fields in monitoring studies

    Science.gov (United States)

    Tuzhilkin, D. A.; Borodin, A. S.

    2015-11-01

    Technological advances have led to a substantial modification of the physical fields of the environment, which could affect the status of living organisms under their constant exposure. In this study, the activity of human cardiovascular system under the influence of a complex natural physical environmental factors investigated. The study was conducted on a representative homogeneous sample (44 persons aged 19 to 22 years) by simultaneous monitoring of electrocardiograms and natural physical fields in Tomsk (geomagnetic field, meteorological parameters - temperature, pressure and humidity, surface wind speed, the parameters of the Schumann resonance - amplitude, frequency and quality factor of the first four modes in the range of 6 to 32 Hz, the power spectral density infrasonic background in the range of from 0,5 to 32 Hz). It was shown that among the set of parameters of physical fields present field that can resonate in the functioning of the human organism. The greatest coherence with heart rate variability detect variations eastern component of the geomagnetic field.

  17. Undergraduate Students' Preference for Distance Education by Field of Study

    Science.gov (United States)

    Pontes, Manuel C. F.; Pontes, Nancy M. H.

    2013-01-01

    This research investigates the relationship between students' field of study and their preference for distance education. For this research, data were used from the National Postsecondary Student Aid Study: Undergraduate, which uses a complex survey design to collect data from a nationally representative sample of undergraduate postsecondary…

  18. Information-Seeking and Sharing Behaviors among Fire Service Field Staff Instructors: A Qualitative Study

    Science.gov (United States)

    Ruan, Lian J.

    2011-01-01

    Fire service field staff instructors seek and share information and use information sources during their instructional work of teaching, training and curriculum development. This study is the first attempt to study their information-seeking and sharing behaviors, which have not previously been investigated empirically. Twenty-five fire service…

  19. Inequality and Doctoral Education: Exploring the "Rules" of Doctoral Study through Bourdieu's Notion of Field

    Science.gov (United States)

    Gopaul, Bryan

    2015-01-01

    While studies have examined a myriad of issues in doctoral study, much of this research has not employed the tools of major social and cultural thinkers to the dynamics of doctoral education. This paper explores the use of Bourdieu's notion of field to render visible the practices and contexts of doctoral education that produce inequalities across…

  20. The University of California Institute of Environmental Stress Marathon Field Studies

    Science.gov (United States)

    Maron, Michael B.

    2014-01-01

    In 1973, the Institute of Environmental Stress of the University of California-Santa Barbara, under the direction of Steven M. Horvath, began a series of field and laboratory studies of marathon runners during competition. As one of Horvath's graduate students, many of these studies became part of my doctoral dissertation. The rationale for…

  1. Citation Analysis for Collection Development: A Comparative Study of Eight Humanities Fields

    Science.gov (United States)

    Knievel, Jennifer E.; Kellsey, Charlene

    2005-01-01

    This study analyzes 9,131 citations from the 2002 volumes of journals in eight humanities fields: art, classics, history, linguistics, literature, music, philosophy, and religion. This study found that citation patterns varied widely among humanities disciplines. Due to these differences, it is important for librarians with humanities collection…

  2. Religious Studies: The Shaping of a Field and a Guide to Reference Resources.

    Science.gov (United States)

    Lippy, Charles H.

    1992-01-01

    Discusses the development of religious studies as an academic discipline. Examines the work of leading thinkers in the field, including anthropologists Sir James Fraser and Edward Burnett Taylor, sociologist Max Weber, and psychologist Erik Erikson. Identifies some of the many reference works that deal with religious studies. (SG)

  3. Supply chain partnership in construction a field study on project team level factors

    NARCIS (Netherlands)

    Koolwijk, J.S.J.; Van Oel, C.J.; Wamelink, J.W.F.

    2015-01-01

    People and their relationship are at the heart of supply chain partnerships, however there is a lack of qualitative studies focusing on how integrated relationships may be developed. Therefore, the purpose of this study was to conduct field research to deepen our understanding of team level

  4. A Simple, Inexpensive, and Field-Relevant Microcosm Tidal Simulator for Use in Marsh Macrophyte Studies

    Directory of Open Access Journals (Sweden)

    Rachel M. MacTavish

    2014-10-01

    Full Text Available Premise of the study: A microcosm unit with tidal simulation was developed to address the challenge of maintaining ecologically relevant tidal regimes while performing controlled greenhouse experiments on smooth cordgrass, Spartina alterniflora. Methods and Results: We designed a simple, inexpensive, easily replicated microcosm unit with tidal simulation and tested whether S. alterniflora growth in microcosms with tidal simulation was similar to that of tidally influenced plants in the field on Sapelo Island, Georgia. After three months of exposure to either natural or simulated tidal treatment, plants in microcosms receiving tidal simulation had similar stem density, height, and above- and belowground biomass to plants in field plots. Conclusions: The tidal simulator developed may provide an inexpensive, effective method for conducting studies on S. alterniflora and other tidally influenced plants in controlled settings to be used not only to complement field studies, but also in locations without coastal access.

  5. The Synergy of Laboratory and Field Studies of Dolphin Behavior and Cognition

    OpenAIRE

    Pack, Adam A.

    2010-01-01

    Dolphin behavior and cognition have been studied in both the laboratory and the wild. Laboratory studies provide high levels of control over experimental variables and the opportunity to investigate the cognitive mechanisms of behavior. However, laboratory studies are typically limited to a few subjects. Field studies have the benefit of examining behavior and social interactions among large numbers of individuals. They can reveal how cognitive abilities are expressed naturally, and can provi...

  6. Evaluation of Theses in the Field of Social Studies Education in Turkey

    Directory of Open Access Journals (Sweden)

    Bülent Tarman

    2010-12-01

    Full Text Available The purpose of this study is to analyze theses in the field of social studies education, and understand certain issues rose through these studies, and determine the awareness level of researchers in Turkey. The theses are examined through computer-based screening system to collect the data. "National Thesis Center" website of Council of Higher Education (CHE is used for this purpose. Besides, the data is collected through the online database system of several university libraries. This is a mixed qualitative and quantitative research study. This study is conducted by scanning and doing content analysis of 294 masters‟ and 41 doctoral theses. These theses were grouped in terms of what research methods used in these studies; which year the studies are completed, and what universities the studies are carried out. Among the total number of 294 Social Studies master‟s theses, 33 of them are about the curriculum while 27 of them are on the student achievement in Social Studies. Examination of these theses shows that the topics of the theses fall within a certain framework of Social Studies. There have rarely seen topics selected to study out of this framework. The results stemming from this research also reveal that different ways of thinking in the field of Social Studies is necessary for development of the field. Therefore, this study has an important role to prevent the accumulation of similar studies in the field by providing guidance to researchers and their academic advisors so that they can generate more effective and efficient human resources in Social Studies

  7. DENTAL ANXIETY AMONG UNIVERSITY STUDENTS AND ITS CORRELATION WITH THEIR FIELD OF STUDY

    OpenAIRE

    Al-Omari, Wael Mousa; Al-Omiri, Mahmoud Khalid

    2009-01-01

    OBJECTIVE: This study was designed to investigate the subjective ratings of dental anxiety levels among university students enrolled at Jordan University of Science and Technology. In addition, the present study aimed to explore the sources of dental anxiety and the impact of gender on the perceived dental anxiety and the correlation between field of study and dental anxiety level. MATERIAL AND METHODS: The Modified Corah Dental Anxiety Scale was used to measure dental anxiety among the study...

  8. Magnetic study of a few antiferromagnets in very-strong pulsed fields (450 kOE)

    International Nuclear Information System (INIS)

    Krebs, J.

    1968-01-01

    In this thesis we describe a pulsed field device with which we obtain magnetization curves up to 450 kOE at all temperatures between 1. 6 and 300. We have studied the 'spin-flopping'(and therefore the anisotropy) in MnF 2 versus temperature, below the Neel point. We have also studied the antiferromagnets MnSO 4 . and MnSO 4 .H 2 O which have revealed saturation fields respectively of 250 kOE and 320 kOE. (author) [fr

  9. Medical terminology across the centuries: distinctive features of a chronological study in the field of ophthalmology

    Directory of Open Access Journals (Sweden)

    María José Esteve Ramos

    2006-10-01

    Full Text Available This article deals with the comparison of the lexical features of two texts from a diachronic point of view. Interest in lexical comparison arises from the fact that the two texts belong to a specialised field within medicine –ophthalmology– and both can be considered of the same genre. The linguistic analysis focuses on morphological and etymological aspects, based on previous studies with a historical perspective in the field of medicine (Norri, 1992. As a result of the study, different implications concerning the use of words from the Germanic native stock or from other sources, together with the different social and scientific changes, are shown in this article.

  10. Field ionization mass spectrometry (FIMS) applied to tracer studies and isotope dilution analysis

    International Nuclear Information System (INIS)

    Anbar, M.; Heck, H.d'A.; McReynolds, J.H.; St John, G.A.

    1975-01-01

    The nonfragmenting nature of field ionization mass spectrometry makes it a preferred technique for the isotopic analysis of multilabeled organic compounds. The possibility of field ionization of nonvolatile thermolabile materials significantly extends the potential uses of this technique beyond those of conventional ionization methods. Multilabeled tracers may be studied in biological systems with a sensitivity comparable to that of radioactive tracers. Isotope dilution analysis may be performed reliably by this technique down to picogram levels. These techniques will be illustrated by a number of current studies using multilabeled metabolites and drugs. The scope and limitations of the methodology are discussed

  11. Effect of Soil Fumigation on Degradation of Pendimethalin and Oxyfluorfen in Laboratory and Ginger Field Studies.

    Science.gov (United States)

    Huang, Bin; Li, Jun; Fang, Wensheng; Liu, Pengfei; Guo, Meixia; Yan, Dongdong; Wang, Qiuxia; Cao, Aocheng

    2016-11-23

    Herbicides are usually applied to agricultural fields following soil fumigation to provide effective weed control in high-value cash crops. However, phytotoxicity has been observed in ginger seedlings following the application of herbicides in fumigated fields. This study tested a mixture of herbicides (pendimethalin and oxyfluorfen) and several fumigant treatments in laboratory and field studies to determine their effect on the growth of ginger. The results showed that soil fumigation significantly (P oxyfluorfen was extended by an average of about 1.19 times in the field and 1.32 times in the laboratory. Moreover, the extended period of herbicide degradation in the fumigant and nonfumigant treatments significantly reduced ginger plant height, leaf number, stem diameter, and the chlorophyll content. The study concluded that applying a dose below the recommended rate of these herbicides in chloropicrin (CP) or CP + 1,3-dichloropropene fumigated ginger fields is appropriate, as application of the recommended herbicide dose in fumigated soil may be phytotoxic to ginger.

  12. Development of Visual Field Screening Procedures: A Case Study of the Octopus Perimeter.

    Science.gov (United States)

    Turpin, Andrew; Myers, Jonathan S; McKendrick, Allison M

    2016-05-01

    We develop a methodology for designing perimetric screening procedures, using Octopus perimeters as a case study. The process has three stages: analytically determining specificity and number of presentations required for different multisampling suprathreshold schemes at a single location of the visual field, ranking visual field locations by their positive predictive value (PPV) for glaucoma, and determining a pass/fail criteria for the test. For the case study the Octopus G-program visual field test pattern is used, and a dataset of 385 glaucoma and 86 normal patients. Using a 1-of-3 sampling strategy at a level equal to the 95 percentile of normal observers gave the most robust specificity under the influences of false-negative responses using an average of 1.5 presentations per location. The PPV analysis gave 19 locations that completely classified our glaucomatous data. A further 9 points were added to screen for nonglaucomatous loss. The final stage found that insisting that 3 locations are missed for the screening to fail gave a simulated specificity and sensitivity of approximately 95% for unreliable responders. Our method gives a principled approach to choosing between the many parameters of a visual field screening procedure. We have developed a procedure for the Octopus that should terminate in less than 1 minute for normal observers with high specificity and sensitivity to glaucoma. Visual field screening is used in community settings and eye care practice. This study provides a principled approach to the development of such screening procedures and details a new procedure.

  13. First principle DFT study of electric field effects on the characteristics of bilayer graphene

    Energy Technology Data Exchange (ETDEWEB)

    Sabzyan, Hassan; Sadeghpour, Narges [Isfahan Univ. (Iran, Islamic Republic of). Dept. of Chemistry

    2017-04-01

    First principle density functional theory methods, local density and Perdew-Burke-Ernzerhof generalized gradient approximations with Goedecker pseudopotential (LDA-G and PBE-G), are used to study the electric field effects on the binding energy and atomic charges of bilayer graphene (BLG) at the Γ point of the Brillouin zone based on two types of unit cells (α and β) containing n{sub C}=8-32 carbon atoms. Results show that application of electric fields of 4-24 V/nm strengths reduces the binding energies and induces charge transfer between the two layers. The transferred charge increases almost linearly with the strength of the electric field for all sizes of the two types of unit cells. Furthermore, the charge transfer calculated with the α-type unit cells is more sensitive to the electric field strength. The calculated field-dependent contour plots of the differential charge densities of the two layers show details of charge density redistribution under the influence of the electric field.

  14. Electric Field Encephalography as a tool for functional brain research: a modeling study.

    Directory of Open Access Journals (Sweden)

    Yury Petrov

    Full Text Available We introduce the notion of Electric Field Encephalography (EFEG based on measuring electric fields of the brain and demonstrate, using computer modeling, that given the appropriate electric field sensors this technique may have significant advantages over the current EEG technique. Unlike EEG, EFEG can be used to measure brain activity in a contactless and reference-free manner at significant distances from the head surface. Principal component analysis using simulated cortical sources demonstrated that electric field sensors positioned 3 cm away from the scalp and characterized by the same signal-to-noise ratio as EEG sensors provided the same number of uncorrelated signals as scalp EEG. When positioned on the scalp, EFEG sensors provided 2-3 times more uncorrelated signals. This significant increase in the number of uncorrelated signals can be used for more accurate assessment of brain states for non-invasive brain-computer interfaces and neurofeedback applications. It also may lead to major improvements in source localization precision. Source localization simulations for the spherical and Boundary Element Method (BEM head models demonstrated that the localization errors are reduced two-fold when using electric fields instead of electric potentials. We have identified several techniques that could be adapted for the measurement of the electric field vector required for EFEG and anticipate that this study will stimulate new experimental approaches to utilize this new tool for functional brain research.

  15. Studies on the reliability of high-field intra-operative MRI in brain glioma resection

    Directory of Open Access Journals (Sweden)

    Zhi-jun SONG

    2011-07-01

    Full Text Available Objective To evaluate the reliability of high-field intra-operative magnetic resonance imaging(iMRI in detecting the residual tumors during glioma resection.Method One hundred and thirty-one cases of brain glioma(69 males and 62 females,aged from 7 to 79 years with mean of 39.6 years hospitalized from Nov.2009 to Aug.2010 were involved in present study.All the patients were evaluated using magnetic resonance imaging(MRI before the operation.The tumors were resected under conventional navigation microscope,and the high-field iMRI was used for all the patients when the operators considered the tumor was satisfactorily resected,while the residual tumor was difficult to detect under the microscope,but resected after being revealed by high-field iMRI.Histopathological examination was performed.The patients without residual tumors recieved high-field MRI scan at day 4 or 5 after operation to evaluate the accuracy of high-field iMRI during operation.Results High quality intra-operative images were obtained by using high-field iMRI.Twenty-eight cases were excluded because their residual tumors were not resected due to their location too close to functional area.Combined with the results of intra-operative histopathological examination and post-operative MRI at the early recovery stage,the sensitivity of high-field iMRI in residual tumor diagnosis was 98.0%(49/50,the specificity was 94.3%(50/53,and the accuracy was 96.1%(99/103.Conclusion High-quality intra-operative imaging could be acquired by high-field iMRI,which maybe used as a safe and reliable method in detecting the residual tumors during glioma resection.

  16. Comparative study of ring current development using empirical, dipolar, and self-consistent magnetic field simulations

    Science.gov (United States)

    Jordanova, V. K.; Zaharia, S.; Welling, D. T.

    2010-12-01

    The effects of nondipolar magnetic field configuration and the feedback of a self-consistently computed magnetic field on ring current dynamics are investigated during a double-dip storm with minima SYM-H = -90 nT at ˜2000 UT, 20 November, and SYM-H = -127 nT at ˜1000 UT, 21 November 2002. We use our kinetic ring current-atmosphere interactions model with self-consistent magnetic field (RAM-SCB) to study the redistribution of plasma in the inner magnetosphere after its fresh injection from the plasma sheet. The kinetic model is fully extended to nondipolar magnetic (B) field geometry and two-way coupled with an Euler-potential-based equilibrium model that calculates self-consistently the three-dimensional magnetic field in force balance with the anisotropic ring current distributions. The ring current source population is inferred from LANL geosynchronous satellite data; a superdense plasma sheet observed during the second storm main phase contributes significantly to ring current buildup. We find that the bounce-averaged velocities increase while the bounce-averaged geocoronal hydrogen densities decrease on the nightside when a nondipolar B field is used. A depression of the ring current fluxes and a confinement of the ring current close to Earth are thus observed on the nightside as geomagnetic activity increases. In contrast to the dipolar case, the proton anisotropy increases considerably in the postnoon sector, and the nondipolar simulations predict the excitation of intense EMIC waves at large L shells. The total ring current energy and ∣Dst∣ index calculated with the self-consistent B field are in best agreement with observations, being smaller compared to the dipolar calculations but larger than the empirical B field predictions.

  17. Does insecticide drift adversely affect grasshoppers (Orthoptera: Saltatoria) in field margins? A case study combining laboratory acute toxicity testing with field monitoring data.

    Science.gov (United States)

    Bundschuh, Rebecca; Schmitz, Juliane; Bundschuh, Mirco; Brühl, Carsten Albrecht

    2012-08-01

    The current terrestrial risk assessment of insecticides regarding nontarget arthropods considers exclusively beneficial organisms, whereas herbivorous insects, such as grasshoppers, are ignored. However, grasshoppers living in field margins or meadows adjacent to crops may potentially be exposed to insecticides due to contact with or ingestion of contaminated food. Therefore, the present study assessed effects of five active ingredients of insecticides (dimethoate, pirimicarb, imidacloprid, lambda-cyhalothrin, and deltamethrin) on the survival of Chorthippus sp. grasshopper nymphs by considering two routes of exposure (contact and oral). The experiments were accompanied by monitoring field margins that neighbored cereals, vineyards, and orchards. Grasslands were used as reference sites. The laboratory toxicity tests revealed a sensitivity of grasshoppers with regard to the insecticides tested in the present study similar to that of the standard test species used in arthropod risk assessments. In the field monitoring program, increasing grasshopper densities were detected with increasing field margin width next to cereals and vineyards, but densities remained low over the whole range of field margins from 0.5 to 20 m next to orchards. Grasshopper densities equivalent to those of grassland sites were only observed in field margins exceeding 9 m in width, except for field margins next to orchards. These results may indicate that current insecticide risk assessments are insufficiently protective for grasshoppers in field margins. Copyright © 2012 SETAC.

  18. mxCSM: A 100-slit, 6-wavelength wide-field coronal spectropolarimeter for the study of the dynamics and the magnetic fields of the solar corona

    Directory of Open Access Journals (Sweden)

    Haosheng eLin

    2016-03-01

    Full Text Available remendous progress has been made in the field of observational coronal magnetometry in the first decade of the 21st century. With the successful construction of the Coronal Multichannel Magnetometer (CoMP instrument, observations of the linear polarization of the coronal emission lines (CELs, which carry information about the azimuthal direction of the coronal magnetic fields, are now routinely available. However, reliable and regular measurements of the circular polarization signals of the CELs remain illusive. The CEL circular polarization signals allow us to infer the magnetic field strength in the corona, and is critically important {bf of} our understanding of the solar corona. Current telescopes and instrument can only measure the coronal magnetic field strength over a small field of view. Furthermore, the observations require very long integration time that preclude the study of dynamic events even when only a small field of view is required. This paper describes a new instrument concept that employees large-scale multiplexing technology to enhance the efficiency of current coronal spectropolarimeter by more than two orders of magnitude. This will allow for the instrument to increase of the integration time at each spatial location by the same factor, while also achieving a large field of view coverage. We will present the conceptual design of a 100-slit coronal spectropolarimeter that can observe six coronal emission lines simultaneously. Instruments based on this concept will allow us to study the evolution of the coronal magnetic field even with coronagraphs with modest aperture.

  19. A simple, inexpensive, and field-relevant microcosm tidal simulator for use in marsh macrophyte studies.

    Science.gov (United States)

    MacTavish, Rachel M; Cohen, Risa A

    2014-11-01

    A microcosm unit with tidal simulation was developed to address the challenge of maintaining ecologically relevant tidal regimes while performing controlled greenhouse experiments on smooth cordgrass, Spartina alterniflora. • We designed a simple, inexpensive, easily replicated microcosm unit with tidal simulation and tested whether S. alterniflora growth in microcosms with tidal simulation was similar to that of tidally influenced plants in the field on Sapelo Island, Georgia. After three months of exposure to either natural or simulated tidal treatment, plants in microcosms receiving tidal simulation had similar stem density, height, and above- and belowground biomass to plants in field plots. • The tidal simulator developed may provide an inexpensive, effective method for conducting studies on S. alterniflora and other tidally influenced plants in controlled settings to be used not only to complement field studies, but also in locations without coastal access.

  20. Hubbard interaction in the arbitrary Chern number insulator: A mean-field study

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yi-Xiang, E-mail: wangyixiang@jiangnan.edu.cn [School of Science, Jiangnan University, Wuxi 214122 (China); Cao, Jie [College of Science, Hohai University, Nanjing 210098 (China)

    2017-05-10

    The low-dimensional electron gas owing topological property has attracted many interests recently. In this work, we study the influence of the electron-electron interaction on the arbitrary Chern number insulator. Using the mean-field method, we approximately solve the Hubbard model in the half-filling case and obtain the phase diagrams in different parametric spaces. We further verify the results by calculating the entanglement spectrum, which contains C chiral modes and corresponds to a real space partitioning. - Highlights: • In this work, we made a mean-field study of the Hubbard interaction in the arbitrary Chern number insulator. • We point out that how the Zeeman splitting, the local magnetization and the Hubbard interaction are intimately related. • The mean-field phase diagrams are obtained in different parametric spaces. • The Chern number phase is demonstrated by calculating the entanglement spectrum.

  1. Planetary Magnetic Fields: Planetary Interiors and Habitability W. M. Keck Institute for Space Studies Report

    Science.gov (United States)

    Lazio, T. Joseph; Shkolnik, Evgenya; Hallinan, Gregg

    2017-05-01

    The W. M. Keck Institute for Space Studies (KISS) sponsored the "Planetary Magnetic Fields: Planetary Interiors and Habitability" study to review the state of knowledge of extrasolar planetary magnetic fields and the prospects for their detection.There were multiple motivations for this Study. Planetary-scale magnetic fields are a window to a planet's interior and provide shielding of the planet's atmosphere. The Earth, Mercury, Ganymede, and the giant planets of the solar system all contain internal dynamo currents that generate planetary-scale magnetic fields. In turn, these internal dynamo currents arise from differential rotation, convection, compositional dynamics, or a combination of these in objects' interiors. If coupled to an energy source, such as the incident kinetic or magnetic energy from the solar wind or an orbiting satellite, a planet's magnetic field can produce intense electron cyclotron masers in its magnetic polar regions. The most well known example of this process in the solar system is the Jovian decametric emission, but all of the giant planets and the Earth contain similar electron cyclotron masers within their magnetospheres. Extrapolated to extrasolar planets, the remote detection of the magnetic field of an extrasolar planet would provide a means of obtaining constraints on the thermal state, composition, and dynamics of its interior--all of which will be difficult to determine by other means--as well as improved understanding of the basic planetary dynamo process.We review the findings from the Study, including potential mission concepts that emerged and recent developments toward one of the mission concepts, a space-based radio wavelength array. There was an identification of that radio wavelength observations would likely be key to making significant progress in this field.We acknowledge ideas and advice from the participants in the "Planetary Magnetic Fields: Planetary Interiors and Habitability" study organized by the W. M. Keck

  2. Site study plan for cultural resources, Deaf Smith County site, Texas: Environmental Field Program: Preliminary draft

    International Nuclear Information System (INIS)

    1987-06-01

    The Cultural Resources Site Study Plan describes a field program to identify and evaluate the archaeological, historical, and Native American Indian resources of the site on local and regional perspectives; monitor and manage discovered cultural resources; and establish a worker education program. The archaeological field program consists of three pedestrian surveys: Survey 1 includes two EDBH seismic survey lines and the area within the exploratory shaft facility (ESF); Survey 2 includes the remainder of the site plus a 1/4 to 3/4-mi border area; and Survey 3 includes an assortment of offsite areas. The historical studies will identify and evaluate known and discovered historical sites and structures and the Native American Indian will identify and evaluate cultural and religious concerns expressed by Indian tribal groups. Prehistoric and historic sites will be evaluated to determine if they meet eligibility criteria for listing on the National Register of Historic Places. This site study plan describes the need for each study; its design and design rationale; analysis, management, and use of data; schedule of field activities; organization of field personnel and sample management; and quality assurance requirements. The cultural resource studies will provide data for satisfying the Programmatic Agreement, engineering design needs, and SRP requirements for permits and approvals, and for minimizing effects to any cultural properties discovered during site characterization. 75 refs., 10 figs., 2 tabs

  3. Numerical study of magnetic field effect on nano-fluid forced convection in a channel

    Energy Technology Data Exchange (ETDEWEB)

    Heidary, H., E-mail: Heidary_ha@aut.ac.ir [Department of Mechanical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran (Iran, Islamic Republic of); Hosseini, R. [Department of Mechanical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran (Iran, Islamic Republic of); Pirmohammadi, M., E-mail: Pirmohamadi@pardisiau.ac.ir [Department of Mechanical Engineering, Pardis Branch, Islamic Azad University, Pardis New City, Tehran (Iran, Islamic Republic of); Kermani, M.J. [Department of Mechanical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran (Iran, Islamic Republic of)

    2015-01-15

    In this study heat transfer and fluid flow analysis in a straight channel utilizing nano-fluid is numerically studied, while flow field is under magnetic field. Usage of nano-particles in base fluid and also applying magnetic field transverse to fluid velocity are two ways recommended in this paper to enhance heat exchange in straight duct. The fluid temperature at the channel inlet (T{sub in}) is taken less than that of the walls (T{sub w}). With assuming thermal equilibrium state of both the fluid phase and nano-particles and ignoring the slip velocity between the phases, single phase approach is used for modeling of nano-fluid. The governing equations are numerically solved in the domain by the control volume approach based on the SIMPLE technique. Numerical studies are performed over a range of Reynolds number, nano-fluid volume fraction and Hartmann number. The influence of these parameters is investigated on the local and average Nusselt numbers. Computations show excellent agreement with the literature. From this study, it is concluded that heat transfer in channels can enhance up to 75% due to the presence of nano-particles and magnetic field in channels. In industrial applications for cooling or heating purposes, the recommended ways in this paper, can provide helpful guidelines to the manufacturers to enhance efficiencies without heat exchanger area increase. - Highlights: • Addition of 10% nano-particles (copper here) can enhance the heat exchange by 26%. • Presence of magnetic field with Ha=30 in pure fluid can enhance the heat exchange by 50%. • Presence of magnetic field and nanofluid with Ha=30 and ϕ=0.1, can enhance the heat exchange by 76%. • Increasing Re{sub H} from 50 to 1000, the average Nu number can increase by a factor of ≈3.

  4. Study of extremely low frequency electromagnetic field (ELF EMF) radiation produced by consumer products

    International Nuclear Information System (INIS)

    Roha Tukimin; Ahmad Fazli Ahmad Sanusi; Rozaimah Abd Rahim; Mohd Yusof Mohd Ali; Mohamad Amirul Nizam Mohamad Thari

    2006-01-01

    Extremely low frequency electromagnetic field ( ELF EMF) radiation falls under category of non-ionising radiation (NIR).ELF EMF consists of electric and magnetic fields. Excessive exposure to ELF EMF radiation may cause biological and health effects to human beings such as behavioral changes, stochastic and as initiator of cancer. In daily life, the main source of extremely low frequency electromagnetic radiation are consumer products in our home and office. Due to its ability to cause hazard, a study of ELF EMF radiation produced by consumer product was conducted. For this preliminary study, sample of 20 types electrical appliances were selected. The measurement was covered electric and magnetic field strength produced by the sample. PMM model EHP50A were used for measurement and data analysis. The results were compared with the permissible limits recommended by International Commission of Non-Ionising Radiation Protection (ICNIRP) for members of public (1000 mGauss and 5000 V/m). The results showed that all tested sample produced magnetic and electric field but still under the permissible limit recommended by ICNIRP. Besides that we found that field strengths can be very high at closer distance to the sample. (Author)

  5. Treatment planning for SBRT using automated field delivery: A case study

    International Nuclear Information System (INIS)

    Ritter, Timothy A.; Owen, Dawn; Brooks, Cassandra M.; Stenmark, Matthew H.

    2015-01-01

    Stereotactic body radiation therapy (SBRT) treatment planning and delivery can be accomplished using a variety of techniques that achieve highly conformal dose distributions. Herein, we describe a template-based automated treatment field approach that enables rapid delivery of more than 20 coplanar fields. A case study is presented to demonstrate how modest adaptations to traditional SBRT planning can be implemented to take clinical advantage of this technology. Treatment was planned for a left-sided lung lesion adjacent to the chest wall using 25 coplanar treatment fields spaced at 11° intervals. The plan spares the contralateral lung and is in compliance with the conformality standards set forth in Radiation Therapy and Oncology Group protocol 0915, and the dose tolerances found in the report of the American Association of Physicists in Medicine Task Group 101. Using a standard template, treatment planning was accomplished in less than 20 minutes, and each 10 Gy fraction was delivered in approximately 5.4 minutes. For those centers equipped with linear accelerators capable of automated treatment field delivery, the use of more than 20 coplanar fields is a viable SBRT planning approach and yields excellent conformality and quality combined with rapid planning and treatment delivery. Although the case study discusses a laterally located lung lesion, this technique can be applied to centrally located tumors with similar results

  6. Study of Research Trend in Knowledge Management Field(2001-2010 and Mapping its Structure

    Directory of Open Access Journals (Sweden)

    Mehri Sedighi

    2013-03-01

    Full Text Available Using scientometric and bibliometric methods, the present study will answer this question: What approach had paid the scientific output in the field of knowledge management at international level in the last decade? For this purpose the first, keywords and subdirectories in this field were identified and selected. Then advanced search of these words were performed in the Web of Science database. All the extracted data from WoS database were entered to the "Histcite" software in the form of 500 record files. After performing the necessary analysis on them, scientific map in this field in 2001-2010 periods was drawn by the software. The study showed average annual growth rate of WoS publications in the field of knowledge management in the last decade, was 10.9 percent. Scientific products of Iranian scientists were included 221 records, and were formed 0.4 percent of the total scientific outputs in this field, and the rank of it, was 35. The most frequent thematic trends were: support information technology like 'data mining' and also organizational, social and managerial elements of knowledge management.

  7. Phase Transitions in Frustrated XY Models Studied Using Hard-Spin Mean-Field Theory

    Science.gov (United States)

    Behzadi, Azad E.; McKay, Susan R.

    1996-03-01

    The number and types of phase transitions occurring in the two- dimensional fully frustrated XY model have remained controversial in spite of over a decade of attention. In this study, we report the results of a hard-spin mean-field approach (R.R. Netz and A.N. Berker, Phys. Rev. Lett. 66), 377 (1991). applied to this system. We compute the effective field on a center site or plaquette using neighboring spins of unit magnitude rather than the average magnetization, as is done in conventional mean-field theory. The directions of the neighboring spins are chosen probabilistically to yield each site magnetization self-consistently. Our calculated inverse critical temperature is 1.444, significantly improved from the conventional mean-field result of 0.707. By locating the self-consistent solutions for the site magnetizations directly, this study avoid scaling, which is complicated in this case due to the possibility of two very closely spaced transitions (P. Ollson, Phys. Rev. Lett. 75), 2758 (1995).. These results are compared with simulations and the Monte Carlo implementation of hard-spin mean-field theory on this system Thesis, Dept. of Physics and Astronomy, U. of Maine (1995).

  8. Site study plan for ecology, Deaf Smith County Site, Texas: Environmental Field Program: Preliminary Draft

    International Nuclear Information System (INIS)

    1987-06-01

    The Ecology Site Study Plan describes a field program consisting of studies which include surveys for endangered, threatened, and candidate species; vegetation characterization, including mapping and cover typing, plant succession, wetlands description, and preexisting stresses; and wildlife community characterization, including availability and quality of habitats and descriptions of mammal, bird, reptile, amphibian, and invertebrate populations. The plan for each study describes the need for the study, study design, data management and use, schedule and personnel requirements, and quality assurance. These studies will provide data needed to satisfy requirements contained in, or derived from, the Salt Repository Project Requirements Document (SRP-RD). 83 refs., 3 tabs

  9. The interface between clinicians and laboratory staff: A field study in northern Tanzania

    Directory of Open Access Journals (Sweden)

    Coosje J. Tuijn

    2014-07-01

    Conclusions: Hospital managers, clinicians and laboratory workers need to recognise the critical and complementary roles each professional plays and the importance of addressing the gap between them. Field application of the framework proved successful, justifying the expansion of this study to a larger geographical area to include additional healthcare institutions

  10. Horizontal Stratification in Access to Danish University Programs by Institution and Field of Study

    DEFF Research Database (Denmark)

    Munk, Martin D.; Thomsen, Jens Peter

    2012-01-01

    to be important: the degree of social stratification in different fields of study − separating applied from more classical disciplines − and the degree of social stratification prevalent at the university institution − whether it has a liberal arts, classical university profile or one that favors more applied...

  11. Simulation supported field study of environmental tobacco smoke leakage from smoking rooms in 19 Dutch pubs

    NARCIS (Netherlands)

    Jacobs, P.; Opperhuizen, A.

    2011-01-01

    Environmental tobacco smoke (ETS) is produced during smoking and smoldering of tobacco products. This field study has measured how much ETS is leaking from smoking rooms into smoke free areas in 19 Dutch cafes. Nicotine, 3-EP and PM2,5 have been used as tracer compounds for ETS. The use of smoking

  12. Engineering studies on joint bar integrity, part I : field surveys and observed failure modes

    Science.gov (United States)

    2014-04-02

    This paper is the first of a two-part series describing a : research project, sponsored by the Federal Railroad : Administration (FRA), to study the structural integrity of joint : bars. In Part I of this series, observations from field surveys : con...

  13. New microscope produced by Lambda Praha Co. applicable to field studies of microorganisms

    Czech Academy of Sciences Publication Activity Database

    Žižka, Zdeněk

    2008-01-01

    Roč. 53, č. 5 (2008), s. 457-461 ISSN 0015-5632 Institutional research plan: CEZ:AV0Z50200510 Keywords : lambda * microscope * field studies Subject RIV: EE - Microbiology, Virology Impact factor: 1.172, year: 2008

  14. Atmospheric Renewable Energy Research, Volume 4: Atmospheric Renewable Energy Field Study Number 2 (ARE2)

    Science.gov (United States)

    2017-10-30

    ARL-TR-8198 ● Oct 2017 US Army Research Laboratory Atmospheric Renewable Energy Research, Volume 4: Atmospheric Renewable Energy ...originator. ARL-TR-8198 ● Oct 2017 US Army Research Laboratory Atmospheric Renewable Energy Research, Volume 4: Atmospheric Renewable... Energy Field Study #2 (ARE2) by Gail Vaucher and Sean D’Arcy Computational and Information Sciences Directorate, ARL Jenna Forrester Advanced

  15. The Selection of Quantitative Undergraduate Fields of Study: Direct and Indirect Influences.

    Science.gov (United States)

    Ethington, Corinna A.; Wolfle, Lee M.

    In order to increase women's representation among quantitative degrees, Berryman (1985) suggested two strategies: (1) increase women's share of the initial mathematical/scientific pool; or (2) reduce attrition from the pool. However, current research indicates that the decision to enter a quantitative field of study for women is the result of a…

  16. On- and off-field antisocial and prosocial behavior in adolescent soccer players: A multilevel study

    NARCIS (Netherlands)

    Rutten, E.A.; Deković, M.; Stams, G.J.J.M.; Schuengel, C.; Hoeksma, J.B.; Biesta, G.J.J.

    2008-01-01

    This study investigated to what extent team membership predicts on- and off-field antisocial and prosocial behavior in (pre)adolescent athletes. Effects of team-membership were related to characteristics of the team environment, such as relational support from the coach towards team members, fair

  17. The special needs of student-athletes in track and field: A case study ...

    African Journals Online (AJOL)

    The special needs of student-athletes in track and field: A case study analysis. ... Student-athletes comprise a pool of talent which is a vital resource for national stakeholders tasked with the development of a country's sporting elite. Underpinned ... Various challenges contributed to the stress experienced by athletes due to

  18. Field-Based Radiographic Imaging of Marine Megafauna: Marine Iguanas (Amblyrhynchus cristatus as a Case Study

    Directory of Open Access Journals (Sweden)

    Gregory A. Lewbart

    2018-02-01

    Full Text Available Effective conservation of marine megafauna requires a thorough understanding of the ecology, physiology, population dynamics, and health of vulnerable species. Assessing the health of large, mobile marine animals poses particular challenges, in part because the subjects are difficult to capture and restrain, and in part because standard laboratory and diagnostic tools are difficult to apply in a field setting. Radiography is a critically important diagnostic tool used routinely by veterinarians, but it has seldom been possible to image live marine vertebrates in the field. As a first step toward assessing the feasibility of incorporating radiography into studies of vulnerable species in remote locations, we used portable radiographic equipment to acquire the first digital internal images of living marine iguanas, Amblyrhynchus cristatus, an iconic lizard endemic only to the Galápagos Islands of Ecuador. The radiographic machinery was powered by batteries and performed well on a rocky beach environment of an uninhabited island, despite high heat and humidity. The accuracy of radiographic measurements was validated by computing a snout-vent length (SVL using bone dimensions and comparing this to standard measurements of SVL made externally with a tape measure. These results demonstrate the feasibility of using radiography to study animals in remote sites, a technique that may prove useful for a variety of physiological, ecological, and biomechanical studies in which reliable measurements of skeletal and soft-tissue dimensions must be acquired under challenging field conditions. Refinements are discussed that will help the technology reach its full potential in field studies.

  19. Self-organization of polyurethane pre-polymers as studied by self-consistent field theory

    NARCIS (Netherlands)

    Li, Feng; Tuinier, Remco; Casteren, Van Ilse; Tennebroek, Ronald; Overbeek, Ad; Leermakers, F.A.M.

    2016-01-01

    Using self-consistent field (SCF) theory, we studied the self-assembly characteristics of polyurethane pre-polymer dispersions in aqueous solutions. With a molecularly detailed model implementing the Scheutjens-Fleer discretization scheme, it is shown how the stability, equilibrium size, and

  20. A field wind tunnel study of fine dust emissions in sandy soils

    Science.gov (United States)

    A portable field wind tunnel has been developed to allow measurements of dust emissions from soil surfaces to test the premise that dust concentration and properties are highly correlated with surface soil properties, as modified by crop management system. In this study, we report on the effect of ...

  1. FIELD-SCALE STUDIES: HOW DOES SOIL SAMPLE PRETREATMENT AFFECT REPRESENTATIVENESS ? (ABSTRACT)

    Science.gov (United States)

    Samples from field-scale studies are very heterogeneous and can contain large soil and rock particles. Oversize materials are often removed before chemical analysis of the soil samples because it is not practical to include these materials. Is the extracted sample representativ...

  2. FIELD-SCALE STUDIES: HOW DOES SOIL SAMPLE PRETREATMENT AFFECT REPRESENTATIVENESS?

    Science.gov (United States)

    Samples from field-scale studies are very heterogeneous and can contain large soil and rock particles. Oversize materials are often removed before chemical analysis of the soil samples because it is not practical to include these materials. Is the extracted sample representativ...

  3. The presence and growth of Legionella species in thermostatic shower mixer taps: an exploratory field study

    NARCIS (Netherlands)

    Joost van Hoof; P.W.J.J. van der Wielen; E. van der Blom; O.W.W. Nuijten; L. Hornstra

    2014-01-01

    Legislation in the Netherlands requires routine analysis of drinking water samples for cultivable Legionella species from high-priority installations. A field study was conducted to investigate the presence of Legionella species in thermostatic shower mixer taps. Water samples and the interior of

  4. The Efficacy of Drama in Field Experience: A Qualitative Study Using MAXQDA

    Science.gov (United States)

    Elaldi, Senel; Yerliyurt, Nazli Sila

    2017-01-01

    This study attempted to evaluate the views of senior preservice preschool teachers on the efficacy of drama activities in their field experience in terms of the effect of students' learning, socialization, individual or group work skills and school connectedness and also disclosed the suggestions of senior preservice preschool teachers for faculty…

  5. Momentum transport studies in JET H-mode discharges with an enhanced toroidal field ripple

    NARCIS (Netherlands)

    de Vries, P. C.; Versloot, T. W.; Salmi, A.; Hua, M. D.; Howell, D. H.; Giroud, C.; Parail, V.; Saibene, G.; Tala, T.

    2010-01-01

    In this study, enhancement of the toroidal field (TF) ripple has been used as a tool in order to reveal the impact of the momentum pinch on the rotation profiles in H-mode JET discharges. The analysis showed that flatter rotation profiles were obtained in discharges with a high TF ripple, attributed

  6. Values, Intelligence and Client Behavior in Career Counseling: A Field Study

    Science.gov (United States)

    Sagiv, Lilach; Schwartz, Shalom H.

    2004-01-01

    We examine relations of values and intelligence to overt behavior in a field study of clients in career counseling (N = 365). Eleven counselors reported their clients' independence, activity and insightfulness behaviors. As predicted, both values and intelligence correlated substantially with particular behaviors. Activity and independence…

  7. Poly(diacetylene) Monolayers Studied with a Fluorescence Scanning Near-Field Optical Microscope

    NARCIS (Netherlands)

    Moers, Marco H.P.; Moers, M.H.P.; Gaub, Hermann E.; van Hulst, N.F.

    1994-01-01

    A novel and powerful method to study the optical properties of thin lipid films which a resolution superior to confocal microscopy is presented. With a scanning near-field optical microscope, fluorescence images of a Langmuir-Blodgett film of diethylene glycol diamine pentacosadiynoic amide are

  8. Studies on the survival of Ascaris suum eggs under laboratory and simulated field conditions

    NARCIS (Netherlands)

    Gaasenbeek, C.P.H.; Borgsteede, F.H.M.

    1998-01-01

    A series of four experiments was carried out to study the survival of Ascaris suum eggs: in a pig slurry unit on a farm, in the laboratory under anaerobic conditions and different relative humidities (rH), and under simulated field conditions. Survival of eggs in the pig slurry unit was 20% after

  9. Affirmative Action in Brazil: How Students' Field of Study Choice Reproduces Social Inequalities

    Science.gov (United States)

    Dias Lopes, Alice

    2017-01-01

    This paper aims to understand which fields of study affirmative action students graduated at the undergraduate level in public universities in Brazil in 2009 and 2010. Public universities began expanding access for underrepresented groups through racial, economic, and social affirmative action policies in 2001. The existing literature on…

  10. Today's talented youth field hockey players, the stars of tomorrow? : a study

    NARCIS (Netherlands)

    Elferink-Gemser, Marije Titia

    2005-01-01

    The aim of the thesis was addressed by conducting research within a group of all talented field hockey players, measuring multidimensional performance characteristics in a sports-specific way, and following talented players across time by adopting a longitudinal study design. With caution because

  11. Modelling indoor electromagnetic fields (EMF) from mobile phone base stations for epidemiological studies

    NARCIS (Netherlands)

    Beekhuizen, J.|info:eu-repo/dai/nl/34472641X; Vermeulen, R.|info:eu-repo/dai/nl/216532620; van Eijsden, M.; van Strien, R.; Bürgi, A.; Loomans, E.; Guxens, M.; Kromhout, H.|info:eu-repo/dai/nl/074385224; Huss, A.|info:eu-repo/dai/nl/331385880

    2014-01-01

    Radio frequency electromagnetic fields (RF-EMF) from mobile phone base stations can be reliably modelled for outdoor locations, using 3D radio wave propagation models that consider antenna characteristics and building geometry. For exposure assessment in epidemiological studies, however, it is

  12. Use of terrestrial field studies in the derivation of bioaccumulation potential of chemicals

    NARCIS (Netherlands)

    Brink, van den N.W.; Arblaster, J.A.; Bowman, S.R.; Conder, J.M.; Elliott, J.E.; Johnson, M.S.; Muir, D.C.G.; Natal-da-Luz, Tiago; Rattner, B.A.; Sample, B.E.; Shore, R.F.

    2016-01-01

    Field-based studies are an essential component of research addressing the behavior of organic chemicals, and a unique line of evidence that can be used to assess bioaccumulation potential in chemical registration programs and aid in development of associated laboratory and modeling efforts. To

  13. Applying Threshold Concepts Theory to an Unsettled Field: An Exploratory Study in Criminal Justice Education

    Science.gov (United States)

    Wimshurst, Kerry

    2011-01-01

    Criminal justice education is a relatively new program in higher education in many countries, and its curriculum and parameters remain unsettled. An exploratory study investigated whether threshold concepts theory provided a useful lens by which to explore student understandings of this multidisciplinary field. Eight high-performing final-year…

  14. Gender composition of college graduates by field of study and early fertility

    Czech Academy of Sciences Publication Activity Database

    Bičáková, Alena; Jurajda, Štěpán

    2017-01-01

    Roč. 15, č. 4 (2017), s. 1323-1343 ISSN 1569-5239 Institutional support: Progres-Q24 Keywords : field-of-study gender segregation * college graduates * fertility Subject RIV: AH - Economics OBOR OECD: Applied Economics, Econometrics Impact factor: 0.972, year: 2016

  15. Gender composition of college graduates by field of study and early fertility

    Czech Academy of Sciences Publication Activity Database

    Bičáková, Alena; Jurajda, Štěpán

    2017-01-01

    Roč. 15, č. 4 (2017), s. 1323-1343 ISSN 1569-5239 R&D Projects: GA ČR(CZ) GBP402/12/G130 Institutional support: RVO:67985998 Keywords : field-of-study gender segregation * college graduates * fertility Subject RIV: AH - Economics OBOR OECD: Applied Economics, Econometrics Impact factor: 0.972, year: 2016

  16. Investigation of exposure to Extremely Low Frequency (ELF) magnetic and electric fields: Ongoing animal studies

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, L.E.

    1994-03-01

    There is now convincing evidence from a large number of laboratories, that exposure to extremely low frequency (ELF) magnetic and electric fields produces biological responses in animals. Many of the observed effects appear to be directly or indirectly associated with the neural or neuroendocrine systems. Such effects include increased neuronal excitability, chemical and hormonal changes in the nervous system, altered behavioral responses, some of which are related to sensing the presence of the field, and changes in endogenous biological rhythms. Additional indices of general physiological status appear relatively unaffected by exposure, although effects have occasionally been described in bone growth and fracture repair, reproduction and development, and immune system function. A major current emphasis in laboratory research is to determine whether or not the reported epidemiological studies that suggest an association between EMF exposure and risk of cancer are supported in studies using animal models. Three major challenges exist for ongoing research: (1) knowledge about the mechanisms underlying observed bioeffects is incomplete, (2) researchers do not as yet understand what physical aspects of exposure produce biological responses, and (3) health consequences resulting from ELF exposure are unknown. Although no animal studies clearly demonstrate deleterious effects of ELF fields, several are suggestive of potential health impacts. From the perspective of laboratory animal studies, this paper will discuss biological responses to ELF magnetic and/or electric field exposures.

  17. Improving hole quality by automatic control of the drilling process: theoretical and field studies

    Energy Technology Data Exchange (ETDEWEB)

    Sinkala, T. (Luleaa University of Technology, Luleaa (Sweden). Division of Mining Equipment Engineering)

    1991-01-01

    Some results from studies on hole deviations are discussed. A system which automatically controls drilling parameters during percussion drilling was developed. A procedure for determining the operating magnitudes of drilling parameters for presetting on a drilling machine is demonstrated. Field experiments show that the automatic control system gives less deviations than ordinary drilling systems. 4 refs., 10 figs., 3 tabs.

  18. Fabrication of a vertical channel field effect transistor and a study of its electrical performances

    International Nuclear Information System (INIS)

    Bhuiyan, A.S.

    1983-01-01

    A vertical channel field effect transistor on silicon was fabricated by diffusion technique and its electrical characteristics were studied as a function of voltage and temperature. It was found that this transistor has relatively high breakdown voltage of 65 volts for drain source and of 7.5 volts for gate source terminals. (author)

  19. Technology as enabler for empowerment in distributed teams - a field study on leadership attitudes.

    NARCIS (Netherlands)

    Bayerl, P.S.; Lauche, K.

    2009-01-01

    In this field study on distributed teams we examined the impact of communication media on attitudes towards empowerment and integration of remote subgroups. Using Q-methodology, interviews and questionnaires we compared attitudes of team members and managers in low and high media-rich environments.

  20. Analytical and computational study of magnetization switching in kinetic Ising systems with demagnetizing fields

    DEFF Research Database (Denmark)

    Richards, H.L.; Rikvold, P.A.

    1996-01-01

    particularly promising as materials for high-density magnetic recording media. In this paper we use analytic arguments and Monte Carlo simulations to quantitatively study the effects of the demagnetizing field on the dynamics of magnetization switching in two-dimensional, single-domain, kinetic Ising systems...

  1. Experimental study of the counting loss in an ionization chamber in pulsed radiation fields

    International Nuclear Information System (INIS)

    Goncalez, O.L.; Yanagihara, L.S.; Veissid, V.L.C.P.; Herdade, S.B.; Teixeira, A.N.

    1983-01-01

    The behavior of an ionization chamber gamma ray monitor in a pulsed radiation field at a linear electron accelerator facility was studied experiementally. A loss of sensitivity was observed as expected due to the pulsed nature of the radiation. By fitting the experiemental data to semi-empirical expressions, parameters for the correction of the counting efficiency were obtained. (Author) [pt

  2. Water Treatment Plant Operation. Volume II. A Field Study Training Program.

    Science.gov (United States)

    California State Univ., Sacramento. School of Engineering.

    The purpose of this water treatment field study training program is to: (1) develop new qualified water treatment plant operators; (2) expand the abilities of existing operators, permitting better service both to employers and public; and (3) prepare operators for civil service and certification examinations (examinations administered by…

  3. Water Treatment Plant Operation. Volume I. A Field Study Training Program.

    Science.gov (United States)

    California State Univ., Sacramento. School of Engineering.

    The purpose of this water treatment field study training program is to: (1) develop new qualified water treatment plant operators; (2) expand the abilities of existing operators, permitting better service both to employers and public; and (3) prepare operators for civil service and certification examinations (examinations administered by…

  4. Water Treatment Plant Operation Volume 2. A Field Study Training Program. Revised.

    Science.gov (United States)

    California State Univ., Sacramento. School of Engineering.

    The purpose of this water treatment field study training program is to: (1) develop new qualified water treatment plant operators; (2) expand the abilities of existing operators, permitting better service both to employers and public; and (3) prepare operators for civil service and certification examinations (examinations administered by…

  5. Operation of Wastewater Treatment Plants. Volume 1. A Field Study Training Program. Third Edition. Revised.

    Science.gov (United States)

    California State Univ., Sacramento. Dept. of Civil Engineering.

    The purpose of this wastewater treatment field study training program is to: (1) develop new qualified wastewater treatment plant operators; (2) expand the abilities of existing operators, permitting better service both to employers and public; and (3) prepare operators for civil service and certification examinations (examinations administered by…

  6. On- and Off-field Antisocial and Prosocial Behavior in Adolescent Soccer Players: A Multilevel Study

    NARCIS (Netherlands)

    Rutten, E.A.; Stams, G.J.; Dekovic, M.; Schuengel, C.; Biesta, G.J.J.; Hoeksma, J.B.

    2008-01-01

    This study investigated to what extent team membership predicts on- and off-field antisocial and prosocial behavior in (pre)adolescent athletes. Effects of team-membership were related to characteristics of the team environment, such as relational support from the coach towards team members, fair

  7. Supplier development and cost management in South-East Asia - Results from a field study

    NARCIS (Netherlands)

    Wouters, Marc; van Jarwaarde, Ewout; Groen, B.A.C.

    2007-01-01

    This paper is about supplier development when international companies have production sites in Southeast Asia and look for opportunities to switch from international suppliers to local suppliers. We conducted a field study involving site visits to companies in Thailand and Vietnam, and interviews at

  8. Accessibility of shared space for visually impaired persons : A comparative field study

    NARCIS (Netherlands)

    Havik, Else; Steyvers, Franciscus J.J.M.; Kooijman, Aart; Melis, Bart

    Shared Space is a concept that comprises the design and planning process of a public space. There are concerns about the accessibility of Shared Spaces for people who are visually impaired. In a comparative field study, the wayfinding performance of 25 visually impaired persons (VIPs) was observed

  9. Use of the data system for field management of a clinical study conducted in Kolkata, India.

    Science.gov (United States)

    Park, Ju Yeon; Kim, Deok Ryun; Haldar, Bisakha; Mallick, Aiyel Haque; Kim, Soon Ae; Dey, Ayan; Nandy, Ranjan Kumar; Paul, Dilip Kumar; Choudhury, Saugata; Sahoo, Shushama; Wierzba, Thomas F; Sur, Dipika; Kanungo, Suman; Ali, Mohammad; Manna, Byomkesh

    2016-01-09

    Designing an appropriate data system is important to the success of a clinical study. However, little information is available on this topic. We share our experiences on designing, developing, and implementation of a data system for management of data and field activities of a complex clinical study. The data system was implemented aiming at determining the biological basis for the underperformance of oral vaccines, such as polio and rotavirus vaccines in children at a site in Kolkata, India. The system included several functionalities to control data and field activities. It was restricted to authorized users based on their access privileges. A relational database platform was chosen, and Microsoft Visual FoxPro 7.0 (Microsoft Corporation, Seattle, WA, USA) was used to develop the system. The system was installed at the clinic and data office to facilitate both the field and data management activities. Data were doubly entered by two different data operators to identify keypunching errors in the data. Outliers, duplication, inconsistencies, missing entries, and linkage were also checked. Every modification and users log-in/log-out information was auto-recorded in an audit trail. The system offered tools for preparation of visit schedule of the participants. A visit considered as protocol deviation was documented by the system. The system alerted field staff to every upcoming visit date to organize the field activities and to inform participants which day to come. The system also produced a growth chart for evaluating nutritional status and referring the child to a specialized clinic if found to be severely malnourished. The data system offered unique features for controlling for both data and field activities, which led to minimize drop-out rates as well as protocol deviations. Such system is warranted for a successful clinical study.

  10. Three-dimensional numerical study on cell performance and transport phenomena of PEM fuel cells with conventional flow fields

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Jer-Huan [Department of Mechanical Engineering, Northern Taiwan Institute of Science and Technology, Beitou, Taipei 11202 (China); Yan, Wei-Mon; Li, Hung-Yi; Tsai, Wei-Che [Department of Mechatronic Engineering, Huafan University, Shih-Ting, Taipei 22305 (China)

    2008-01-15

    In this paper, a three-dimensional numerical model of the proton exchange membrane fuel cells (PEMFCs) with conventional flow field designs (parallel flow field, Z-type flow field, and serpentine flow field) has been established to investigate the performance and transport phenomena in the PEMFCs. The influences of the flow field designs on the fuel utilization, the water removal, and the cell performance of the PEMFC are studied. The distributions of velocity, oxygen mass fraction, current density, liquid water, and pressure with the convention flow fields are presented. For the conventional flow fields, the cell performance can be enhanced by adding the corner number, increasing the flow channel length, and decreasing the flow channel number. The cell performance of the serpentine flow field is the best, followed by the Z-type flow field and then the parallel flow field. (author)

  11. Modeling of a Parabolic Trough Solar Field for Acceptance Testing: A Case Study

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, M. J.; Mehos, M. S.; Kearney, D. W.; McMahan, A. C.

    2011-01-01

    As deployment of parabolic trough concentrating solar power (CSP) systems ramps up, the need for reliable and robust performance acceptance test guidelines for the solar field is also amplified. Project owners and/or EPC contractors often require extensive solar field performance testing as part of the plant commissioning process in order to ensure that actual solar field performance satisfies both technical specifications and performance guaranties between the involved parties. Performance test code work is currently underway at the National Renewable Energy Laboratory (NREL) in collaboration with the SolarPACES Task-I activity, and within the ASME PTC-52 committee. One important aspect of acceptance testing is the selection of a robust technology performance model. NREL1 has developed a detailed parabolic trough performance model within the SAM software tool. This model is capable of predicting solar field, sub-system, and component performance. It has further been modified for this work to support calculation at subhourly time steps. This paper presents the methodology and results of a case study comparing actual performance data for a parabolic trough solar field to the predicted results using the modified SAM trough model. Due to data limitations, the methodology is applied to a single collector loop, though it applies to larger subfields and entire solar fields. Special consideration is provided for the model formulation, improvements to the model formulation based on comparison with the collected data, and uncertainty associated with the measured data. Additionally, this paper identifies modeling considerations that are of particular importance in the solar field acceptance testing process and uses the model to provide preliminary recommendations regarding acceptable steady-state testing conditions at the single-loop level.

  12. The mathematical basis of business logistics as a field of study

    Directory of Open Access Journals (Sweden)

    William J. Pienaar

    2006-09-01

    Full Text Available This article describes the meaning of the word logistics, outlines its mathematical basis and explains the meaning thereof as a contemporary field of study. The concept of logistics management is described in a business context and the strategic, tactical and operational tiers thereof are identified. The relationship that exists between systems analysis and logistics management is indicated. The role and essence of operations research in logistics decision- making are described. The most pertinent operations research topics in the field of logistics as well as the mathematical competencies a logistician should possess, are identified.

  13. Study of the correspondence between dual thermal transformations and gauge fields

    International Nuclear Information System (INIS)

    Civitarese, O.; De Paoli, A.L.; Rocca, M.C.

    1995-01-01

    The correspondence between dual thermal transformations of the thermo field dynamics (TFD) and gauge fields is studied both for abelian and non-abelian theories. It is found that the action for the TFD representation of a Dirac's lagrangian remains invariant under local transformations in k-space. The conserved charge coincides with the TFD vacuum-generator G introduced by Takahashi and Umezawa. The relationship between the rules of the TFD and the principle of gauge invariance in a thermal subspace is discussed in the context of a thermal symmetry breaking. ((orig.))

  14. Accelerating field spectrometer for photons and electrons simultaneous measurement. Application to decay schemes study

    International Nuclear Information System (INIS)

    Busani, Jean.

    1982-09-01

    An original spectrometer was built to improve the measurement of the absolute emission intensities of radionuclides with converted low energy gamma transitions. In this spectrometer, the same Si(Li) detector simultaneously measures electrons and photons emitted by the studied radionuclide; an electrostatic field may be established between the source and the detector to modify the electrons energy. This field allows the electron and photon peaks to be separated, and the absorption and energy straggling by detector windows to be decreased. Special attention has been given to determine spectrometer efficiency calibration curves for electrons and photons. 147 Nd and 133 Ba were used to test the spectrometer improvement and the method used [fr

  15. Conceptual studies of toroidal field magnets for the tokamak experimental power reactor. Final report

    International Nuclear Information System (INIS)

    Buncher, B.R.; Chi, J.W.H.; Fernandez, R.

    1976-01-01

    This report documents the principal results of a Conceptual Design Study for the Superconducting Toroidal Field System for a Tokamak Experimental Power Reactor. Two concepts are described for peak operating fields at the windings of 8 tesla, and 12 tesla, respectively. The design and manufacturing considerations are treated in sufficient detail that cost and schedule estimates could be developed. Major uncertainties in the design are identified and their potential impact discussed, along with recommendations for the necessary research and development programs to minimize these uncertainties. The minimum dimensions of a sub-size test coil for experimental qualification of the full size design are developed and a test program is recommended

  16. Experimental studies of random-field effects in uniaxial random antiferromagnets

    International Nuclear Information System (INIS)

    Wong, P.Z.; Cable, J.W.; von Molnar, S.; Dimon, P.

    1983-11-01

    We discuss how random fields (RFs) are generated in uniaxial random antiferromagnets (URAFs) by applied fields and review the experiments that have been performed on these systems. They include direct and indirect specific heat measurements, neutron scattering experiments and phase diagram studies. We compare the results of different experiments on different systems, discuss their implications on the theories, and suggest further experiments. A new explanation for the Lorentzian-squared (LSQ) structure factor observed in the neutron scattering experiments is also given. 47 references, 4 figures

  17. Experimental study on the critical heat flux in a varying acceleration field, (1)

    International Nuclear Information System (INIS)

    Kusunoki, Tsuyoshi; Yokomura, Takeyoshi; Otsuji, Tomoo; Ikawa, Masahiro; Kurosawa, Akira.

    1988-12-01

    It is very important for the thermohydraulic design and for the safety assesement of marine reactors, to understand the effect of varying acceleration induced by ship motion on critical heart flux. The purpose of this joint study is to examine quantitatively the influence of varying acceleration on the behavior of bubbles. In the experiment, FREON-113 was used as working fluid. This report describes some experimental results; measurements of void fraction and bubble velocity near the heat transfer surface, measurement of bubble size under stationary acceleration field and observation of bubble behavior under varying acceleration field. (author)

  18. Studying internal and external magnetic fields in Japan using MAGSAT data

    Science.gov (United States)

    Fukushima, N. (Principal Investigator); Maeda, H.; Yukutake, T.; Tanaka, M.; Oshima, S.; Ogawa, K.; Kawamura, M.; Miyazaki, Y.; Uyeda, S.; Kobayashi, K.

    1980-01-01

    Examination of the total intensity data of CHRONIT on a few paths over Japan and its neighboring sea shows MAGSAT is extremely useful for studying the local magnetic anomaly. In high latitudes, the signatures of field aligned currents are clearly recognized. These include (1) the persistent basic pattern of current flow; (2) the more intense currents in the summer hemisphere than in the winter hemisphere; (3) more fluctuations in current intensities in summer dawn hours; and (4) apparent dawn-dusk asymmetry in the field-aligned current intensity between the north and south polar regions.

  19. FLOC: Field Line and Orbit Code for the study of ripple beam injection into tokamaks

    International Nuclear Information System (INIS)

    Fowler, R.H.; Lee, D.K.; Gaffney, P.W.; Rome, J.A.

    1978-06-01

    The computer code described is used to study ripple beam injection into a tokamak plasma. The collisionless guiding center equations of motion are integrated to find the orbits of single particles in realistic magnetic fields for ripple injection. In order to determine if the ripple is detrimental to the plasma, the magnetic flux surfaces are constructed by integration of the field line equations. The numerical techniques are described, and use of the code is outlined. A program listing is provided, and the results of sample cases are presented

  20. Mining and territory: theoretical approaches to the field of environmental history through a case study

    Directory of Open Access Journals (Sweden)

    Francesco Panico

    2018-09-01

    Full Text Available This article aims to outline an epistemological framework for placing the field of environmental history in the context of the current endeavor of social sciences and humanities. The methodology used is defined here as “metabolic landmarks” because it is inspired by the approach of social metabolism. The results suggest that, in the study of environmental history, the specific historiographical object plays an essential role in defining the epistemic context of that hybrid field of historiography and, more generally, of social and environmental analyses.

  1. Experimental studies of random-field effects in uniaxial random antiferromagnets

    Energy Technology Data Exchange (ETDEWEB)

    Wong, P.Z.; Cable, J.W.; von Molnar, S.; Dimon, P.

    1983-11-01

    We discuss how random fields (RFs) are generated in uniaxial random antiferromagnets (URAFs) by applied fields and review the experiments that have been performed on these systems. They include direct and indirect specific heat measurements, neutron scattering experiments and phase diagram studies. We compare the results of different experiments on different systems, discuss their implications on the theories, and suggest further experiments. A new explanation for the Lorentzian-squared (LSQ) structure factor observed in the neutron scattering experiments is also given. 47 references, 4 figures.

  2. Technical Note: A Monte Carlo study of magnetic-field-induced radiation dose effects in mice

    Energy Technology Data Exchange (ETDEWEB)

    Rubinstein, Ashley E. [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 and The University of Texas Graduate School of Biomedical Sciences, Houston, Texas 77030 (United States); Liao, Zhongxing [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Melancon, Adam D.; Followill, David S.; Tailor, Ramesh C. [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Guindani, Michele [Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Hazle, John D. [Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Court, Laurence E., E-mail: lecourt@mdanderson.org [Departments of Radiation Physics and Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States)

    2015-09-15

    Purpose: Magnetic fields are known to alter radiation dose deposition. Before patients receive treatment using an MRI-linear accelerator (MRI-Linac), preclinical studies are needed to understand the biological consequences of magnetic-field-induced dose effects. In the present study, the authors sought to identify a beam energy and magnetic field strength combination suitable for preclinical murine experiments. Methods: Magnetic field dose effects were simulated in a mouse lung phantom using various beam energies (225 kVp, 350 kVp, 662 keV [Cs-137], 2 MV, and 1.25 MeV [Co-60]) and magnetic field strengths (0.75, 1.5, and 3 T). The resulting dose distributions were compared with those in a simulated human lung phantom irradiated with a 6 or 8 MV beam and orthogonal 1.5 T magnetic field. Results: In the human lung phantom, the authors observed a dose increase of 45% and 54% at the soft-tissue-to-lung interface and a dose decrease of 41% and 48% at the lung-to-soft-tissue interface for the 6 and 8 MV beams, respectively. In the mouse simulations, the magnetic fields had no measurable effect on the 225 or 350 kVp dose distribution. The dose increases with the Cs-137 beam for the 0.75, 1.5, and 3 T magnetic fields were 9%, 29%, and 42%, respectively. The dose decreases were 9%, 21%, and 37%. For the 2 MV beam, the dose increases were 16%, 33%, and 31% and the dose decreases were 9%, 19%, and 30%. For the Co-60 beam, the dose increases were 19%, 54%, and 44%, and the dose decreases were 19%, 42%, and 40%. Conclusions: The magnetic field dose effects in the mouse phantom using a Cs-137, 3 T combination or a Co-60, 1.5 or 3 T combination most closely resemble those in simulated human treatments with a 6 MV, 1.5 T MRI-Linac. The effects with a Co-60, 1.5 T combination most closely resemble those in simulated human treatments with an 8 MV, 1.5 T MRI-Linac.

  3. Salmon cycles: Influences of a science field study immersion experience with Native American young women

    Science.gov (United States)

    Ault, Phyllis Campbell

    Native Americans, and particularly Native women, are not proportionally represented in higher education, or in science, mathematics, technology, and engineering fields. This study examined an out-of-school science education program which combined traditional Native American cultural and ecological knowledge with Western science in conducting authentic field studies. A qualitative, embedded case study approach was used to explore how young Native American women were influenced by an out-of-school program integrating a culturally responsive approach and experiential research projects. Within this context of combined cultures, three significant domains emerged: field study in science, sense of place, and networks of supportive relationships. These domains interacted with the aspirations of the eight Native women in the study. Using interview transcripts, reflective writings, and participant data, the study explored the blending of Indigenous and Western science in "communities of practice" (e.g., fisheries biology, restoration ecology, and forestry). The eight Native women in this study participated as young adolescents and later returned as counselors. Interviews focused on their postsecondary aspirations and choices. Findings validated previous research on the value of infusing Traditional Ecological Knowledge and Western science for Native students. The study found the combination of culturally responsive pedagogy and authentic experiences in "communities-of-practice" held a beneficial influence on postsecondary pathways. The importance of respect and friendships fostered through the program was associated with resilience and perseverance in educational aspirations. Immersion in field study with Native peers as well as Native and non-Native researchers was a catalyst for all the women, in a number of different ways, such as: deeper involvement with the Native community, strengthening cultural and academic identity, inspiration to learn more about their cultural

  4. Study of two medium size 'C' core electromagnets generating low magnetic fields

    International Nuclear Information System (INIS)

    Bhatia, M.S.; Dass, S.; Chatterjee, U.K.

    1987-01-01

    Magnetic field requirements of laboratories may impose constraints that often call for a variety of non-standard designs. The designer has to fulfil these demands without letting the design to become too inefficient. Since no ready design procedures are available he has to resort to intuition calculation and modelling. In spite of this there may be wide discrepancy between the design values and the actual results. This report describes the experience gained on two 'C' core electromagnets being used by authors. These magnets generate low magnetic fields over reasonably large volumes, a requirement that runs opposite to that of most other magnets. The study reveals the dependence of overall performance efficiency, field uniformity etc. on the design parameters. 31 figures. (author)

  5. A Study on Scattered Field of Ultrasonic Wave Using the Boundary Element Method

    International Nuclear Information System (INIS)

    Lee, Joon Hyun; Lee, Seo Il

    2000-01-01

    Ultrasonic technique which is one of the most common and reliable nondestructive evaluation techniques has been applied to evaluate the integrity of structures by analyzing the characteristics of signal scattered from internal defects. Therefore, the numerical analysis of the ultrasonic scattered field is absolutely necessary for the accurate and quantitative estimation of internal defects. Various modeling techniques now play an important role in nondestructive evaluation and have been employed to solve elastic wave scattering problems. Because the elastodynamic boundary element method is useful to analyze the scattered field in infinite media. it has been used to calculate the ultrasonic wavefields scattered from internal defects. In this study, a review of the boundary element method used for elastic wave scattering problems is presented and, as examples of the boundary element method, the scattered fields due to a circular cavity subjected to incident SH-wave and due to a surface-breaking crack subjected to incident Rayleigh wave are illustrated

  6. Study of the neutron skin thickness of 208Pb in mean field models

    International Nuclear Information System (INIS)

    Roca-Maza, X; Centelles, M; Vinas, X; Warda, M

    2011-01-01

    We study whether the neutron skin thickness Δr np of 208 Pb originates from the bulk or from the surface of the neutron and proton density distributions in mean field models. We find that the size of the bulk contribution to Δr np of 208 Pb strongly depends on the slope of the nuclear symmetry energy, while the surface contribution does not. We note that most mean field models predict a neutron density for 208 Pb between the halo and skin type limits. We investigate the dependence of parity-violating electron scattering at the kinematics of the PREX experiment on the shape of the nucleon densities predicted by the mean field models for 208 Pb. We find an approximate formula for the parity-violating asymmetry in terms of the central radius and the surface diffuseness of the nucleon densities of 208 Pb in these models.

  7. Internal Flow Field Uniformity Study of Dust Collector for A Street Vacuum Sweeper Based on CFD

    Science.gov (United States)

    Xi, Yuan; Dai, Yan; Xiao, Yonghou; Cheng, Kai; Xiao, Tao; Zhao, Shixiang

    2017-12-01

    Internal flow field of dust collector for a street vacuum is studied by Computational Fluid Dynamics (CFD). The causes of uneven distribution of flow field were diagnosed by simulation, and an improvement measure was put forward. The result shows that flow ratce distribution of dust collector is uneven, the reason for which is the higher wind velocity at the Inlet. A baffle plate was added at the Inlet to improve the uniformity of internal flow field. The main technical parameters, maximum flow rate uneven amplitude Δk i and overall flow rate uneven amplitude Δ \\bar{{k}i} and overall flow rate uneven amplitude, are decreased in this way. Δk is reduced from 0.3429 to 0.1308. While Δ \\bar{{k}i} is reduced from 0.1012 to 0.0402.

  8. Study of Strong Magnetic Fields Using Parametric Instability in a Magnetised Plasma

    Science.gov (United States)

    Ivanov, V. V.; Maximov, A. V.; Anderson, A. A.; Bauer, B. S.; Yates, K.

    2014-10-01

    Generation of strong magnetic fields with a strength of 10--50 MG plays a key role in some recent conceptions for controlled fusion. We suggest a laser method for measuring the local magnetic field, B > 10 MG, based on the parametric decay of the laser radiation to ω/2 and 3/2 ω harmonics which are generated in the area with the electron density of a quarter of the critical plasma density. Spectral components of parametric harmonics carry a signature of both the plasma temperature and strong magnetic field. A two-plasmon decay of laser radiation was studied in a magnetized plasma at the 1 MA pulsed power Zebra facility at the University of Nevada, Reno. Dense magnetized plasma with a magnetic field of 1--3 MG was created by the 1MA current flowing in the metal rod 0.7--2 mm in diameter. Radiation from the narrowband laser with intensity >1014 W/cm2 was focused on the surface plasma. Spectrum of the backscattering 3/2 ω harmonic included ``red'' and ``blue'' shifted components. Large 2-3 nm shifts of spectral components was identified with laser heating of plasma. Components with a small 0.1 nm spectral shift of may be linked to the magnetic field. Work was supported by the DOE Grant DE-SC0008824 and DOE/NNSA UNR Grant DE-FC52-06NA27616.

  9. A Numerical Study of Near-Field Dispersion within and above Forest Canopies

    Science.gov (United States)

    Edburg, Steven; Stock, David; Lamb, Brian; Thistle, Harold

    2004-11-01

    Pine beetle infestations have impacted recreational uses, wildlife habitat, and silvicultural practice in forest stands throughout the US and Canada. Pheromone releases are used by forest managers as an anti-aggregation technique to protect high value forest stands against the pine beetle. As a result, near-field pheromone dispersion patterns are needed to develop effective forest management techniques. Recent field experiments have shown a strong link between tracer gas dispersion, meteorological data and canopy density. However, field experiments are limited by cost, location, meteorological conditions etc. Analytical and numerical models are a cost effective solution to study multiple cases, while having control over meteorological parameters. In this research, numerical simulations were conducted, and the Reynolds stress model, RSM, and large eddy simulation, LES, were used to predict near-field concentrations of a tracer gas in a pine canopy. The canopy was represented with porous media based on leaf area index and basal area. Unstable atmospheric conditions were prescribed with solar radiation absorption in the canopy. Results were compared with meteorological data and thirty minute concentration averages from a field experiment. The steady RSM solution showed reasonable comparison with experimental data, although it did not capture the dynamics of the flow. Unsteady LES captured the time dependency of the flow and dispersion patterns. Future work will consist of modeling canopies that are not continuous and dispersion during stable atmospheric conditions. Bursting and sweeping affects on dispersion will also be investigated.

  10. Analytical study of a Kerr-Sen black hole and a charged massive scalar field

    Science.gov (United States)

    Bernard, Canisius

    2017-11-01

    It is reported that Kerr-Newman and Kerr-Sen black holes are unstable to perturbations of charged massive scalar field. In this paper, we study analytically the complex frequencies which characterize charged massive scalar fields in a near-extremal Kerr-Sen black hole. For near-extremal Kerr-Sen black holes and for charged massive scalar fields in the eikonal large-mass M ≫μ regime, where M is the mass of the black hole, and μ is the mass of the charged scalar field, we have obtained a simple expression for the dimensionless ratio ωI/(ωR-ωc) , where ωI and ωR are, respectively, the imaginary and real parts of the frequency of the modes, and ωc is the critical frequency for the onset of super-radiance. We have also found our expression is consistent with the result of Hod [Phys. Rev. D 94, 044036 (2016), 10.1103/PhysRevD.94.044036] for the case of a near-extremal Kerr-Newman black hole and the result of Zouros and Eardly [Ann. Phys. (N.Y.) 118, 139 (1979), 10.1016/0003-4916(79)90237-9] for the case of neutral scalar fields in the background of a near-extremal Kerr black hole.

  11. Site Study Plan for land use, Deaf Smith County site, Texas: Environmental Field Program: Preliminary draft

    International Nuclear Information System (INIS)

    1987-06-01

    The Land Use Site Study Plan describes a field program consisting of characterization of the site; seismic survey rights-of-way and transportation and utility corridors, the vicinity, the region, future land use, and monitoring land-use change. Aerial photography will be used to characterize the site, seismic rows and transportation and utility corridors, and the vicinity. The resulting land-use maps and overlays will then be verified in the field. Interviews with farm managers and local experts will provide additional information. A Geographic Information System (GIS) and satellite imagery will be used to characterize the region, monitor land-use change, and provide information to assist with the future land use study. The site study plan describes the study design and rationale, the filed data collection procedures and equipment, the data analysis methods and application of results, the data management strategy, the schedule of field activities, the personnel requirements and management of the study, and the study's quality assurance program. The directives and requirements that drive these studies are derived from the Salt Repository Project Requirements Document. 51 refs; 6 figs; 3 tabs

  12. Site Study Plan for Aesthetics, Deaf Smith County Site, Texas: Environmental Field Program: Preliminary draft

    International Nuclear Information System (INIS)

    1987-06-01

    The Aesthetic Site Study Plan describes a field program consisting of identification of the visually affected area; determination of scenic quality, visual sensitivity, and visual management classes of the site and vicinity; and analysis of the level of visual contrast that would be created by the project. Field ratings of scenic quality, visual sensitivity, and visual contrast will be supplemented by a public perception survey designed to incorporate the views of the public. This plan describes the need for the study, the study design, data management and use, schedule for proposed activities, and quality assurance program. This study will provide data needed to satisfy requirements contained in, or derived from, SRPO Requirement Document (SRP-RD). 35 refs., 6 figs., 2 tabs

  13. Does a dynamic chair increase office workers' movements? - Results from a combined laboratory and field study.

    Science.gov (United States)

    Grooten, Wilhelmus J A; Äng, Björn O; Hagströmer, Maria; Conradsson, David; Nero, Håkan; Franzén, Erika

    2017-04-01

    Dynamic chairs have the potential to facilitate movements that could counteract health problems associated with sedentary office work. This study aimed to evaluate whether a dynamic chair can increase movements during desk-based office work. Fifteen healthy subjects performed desk-based office work using a dynamic office chair and compared to three other conditions in a movement laboratory. In a field study, the dynamic office chair was studied during three working days using accelerometry. Equivocal results showed that the dynamic chair increased upper body and chair movements as compared to the conventional chair, but lesser movements were found compared to standing. No differences were found between the conditions in the field study. A dynamic chair may facilitate movements in static desk-based office tasks, but the results were not consistent for all outcome measures. Validation of measuring protocols for assessing movements during desk-based office work is warranted. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Using field notes to evaluate competencies in family medicine training: a study of predictors of intention

    OpenAIRE

    Lacasse, Miriam; Douville, Frédéric; Desrosiers, Émilie; Côté, Luc; Turcotte, Stéphane; Légaré, France

    2013-01-01

    Background: Documenting feedback during clinical supervision using field notes (FN) is a recommended competency-based evaluation strategy that will require changes in the culture of medical education. This study identified factors influencing the intention to adopt FN in family medicine training, using the theory of planned behaviour. Methods: This mixed-methods study involved clinical teachers (CT) and residents from two family medicine units. Main outcomes were: 1) intention (and its pre...

  15. Degradation of herbicides in shallow Danish aquifers - an integrated laboratory and field study

    DEFF Research Database (Denmark)

    Albrechtsen, Hans-Jørgen; Mills, M.; Aamand, J.

    2001-01-01

    of aerobic versus anaerobic conditions, and the importance of concentration on degradation kinetics for a selected range of herbicides. The studies were based on different experimental approaches ranging from simple batch experiments to column studies to field injection experiments and, where appropriate......, results were compared. Some herbicides were degraded under aerobic conditions (some phenoxy acids, DNOC and glyphosate) and others under aerobic conditions (other phenoxy acids, DNOC; there was some indication of atrazine transformation). Certain pesticides were not degraded in any investigations...

  16. Experimental studies of tearing mode and resistive wall mode dynamics in the reversed field pinch configuration

    OpenAIRE

    Malmberg, Jenny-Ann

    2003-01-01

    It is relatively straightforward to establish equilibrium inmagnetically confined plasmas, but the plasma is frequentlysucceptible to a variety of instabilities that are driven bythe free energy in the magnetic field or in the pressuregradient. These unstable modes exhibit effects that affect theparticle, momentum and heat confinement properties of theconfiguration. Studies of the dynamics of several of the mostimportant modes are the subject of this thesis. The studies arecarried out on plas...

  17. Study of soil redistribution in cultivated fields using fallout cesium-137 at Fateh Jang, Attock, Pakistan

    International Nuclear Information System (INIS)

    Ahmad, M.; Rafique, M.; Iqbal, N.; Akram, W.; Aasi, M.R.

    2009-11-01

    The study was carried out to investigate soil redistribution and net soil losses from two cultivated fields located in the dissected loess plains in the Pothwar Plateau at Mangial (33.6 N; 72.8 E), District Attock, Pakistan. For reference site, soil samples were collected by scrapper plate at 2 cm intervals and bulk cores in a grid, while the cultivated fields were sampled taking bulk cores in grid and along transect. /sup 137/Cs was measured by gamma spectroscopy using Soil 6 (IAEA) as a standard. The established reference inventory of /sup 137/Cs for this area is 3204 Bq/m/sup 2/. The technique provides very clear quantitative information on medium-term erosion and deposition rates at different locations, and net soil loss from cultivated fields, while no other methods available can be applied so simply. Gradient of the cultivated fields play an important role in the soil redistribution and net soil loss. Due to higher gradient of Field 2, the net soil losses determined by PM and MBM-1 using 20 cm plough layer (14.18 t ha/sup -1/ yr/sup -1/ and 16.37 t ha/sup -1/ yr/sup -1/ respectively) are much higher than that for Field 1 determined by the same models (0.24 t ha-1 yr-1 and 3.84 t ha/sup -1/ yr/sup -1/). Therefore, the cultivated fields should be as much leveled as possible. Major implication arises in using soil conversion models when thickness of /sup 137/Cs bearing layer becomes more than the normal plough layer due to deposition of eroded soil at low-lying areas. In case of Field 2, using 30 cm thickness of plough layer having significant /sup 137/Cs in the deposition areas the net erosion estimates using by PM and MBM-1 are 8.71 t ha/sup -1/ yr/sup -1/ and 10.05 t ha-1 yr/sup -1/, respectively, which seem more reliable because maximum /sup 137/Cs inventory is taken into accounted. The herbicide residue varies spatially in the field, but these three distributions corresponding to the three sampling dates indicate reduction in the residue with time. The

  18. Numerical Studies of the Heat and Mass Transport in the Cerro Prieto Geothermal Field, Mexico

    Science.gov (United States)

    Lippmann, M. J.; Bodavarsson, G. S.

    1983-06-01

    Numerical simulation techniques are employed in studies of the natural flow of heat and mass through the Cerro Prieto reservoir, Mexico and of the effects of exploitation on the field's behavior. The reservoir model is a two-dimensional vertical east to west-southwest cross section, which is based on a recent hydrogeologic model of this geothermal system. The numerical code MULKOM is used in the simulation studies. The steady state pressure and temperature distributions are computed and compared against observed preproduction pressures and temperatures; a reasonable match is obtained. A natural hot water recharge rate of about 1×10-2 kg/s per meter of field length (measured in a north-south direction) is obtained. The model is then used to simulate the behavior of the field during the 1973-1978 production period. The response of the model to fluid extraction agrees to what has been observed in the field or postulated by other authors. There is a decrease in temperatures and pressures in the produced region. No extensive two-phase zone develops in the reservoir because of the strong fluid recharge. Most of the fluid recharging the system comes from colder regions located above and west of the produced reservoir.

  19. Experimental Study of Soil Organic Matter Loss From Cultivated Field Plots In The Venezuelan Andes.

    Science.gov (United States)

    Bellanger, B.; Huon, S.; Velasquez, F.; Vallès, V.; Girardin A, C.; Mariotti, A. B.

    The question of discriminating sources of organic matter in suspended particles of stream flows can be addressed by using total organic carbon (TOC) concentration and stable isotope (13C, 15N) measurements when constant fluxes of organic matter supply can be assumed. However, little is known on the dynamics of organic matter release during soil erosion and on the temporal stability of its isotopic signature. In this study, we have monitored soil organic carbon loss and water runoff using natural rainfall events on three experimental field plots with different vegetation cover (bare soil, maize and coffee fields), set up on natural slopes of a tropical mountainous watershed in NW Venezuela (09°13'32'' ­ 09°10'00''N, 70°13'49'' ­ 70°18'34''W). Runoff and soil loss are markedly superior for the bare field plot than for the coffee field plot: by a factor 15 ­ 36, respectively, for the five-month experiment, and by a factor 30 ­ 120, respectively, during a single rainfall event experiment. Since runoff and soil organic matter loss are closely linked during most of the flow (at the time scales of this study), TOC concentration in suspended matter is constant. Furthermore, stable isotope compositions reflect those of top-soil organic matter from which they originate.

  20. Corrosion of metals exposed to 25% magnesium chloride solution and tensile stress: Field and laboratory studies

    Directory of Open Access Journals (Sweden)

    Xianming Shi

    2017-12-01

    Full Text Available The use of chemicals for snow and ice control operations is a common practice for improving the safety and mobility of roadways in cold climate, but brings significant concerns over their risks including the corrosive effects on transportation infrastructure and motor vehicles. The vast majority of existing studies and methods to test the deicer corrosivity have been restricted to laboratory environments and unstressed metals, which may not reliably simulate actual service conditions. As such, we report a case study in which stainless steel SS 304 (unstressed and externally tensile stressed, aluminum (Al 1100 and low carbon steel (C1010 coupons were exposed to 25% MgCl2 under field conditions for six weeks. A new corrosion test-bed was developed in Montana to accelerate the field exposure to this deicer. To further investigate the observed effect of tensile stress on the corrosion of stainless steel, SS 304 (unstressed and externally stressed coupons were exposed to 25% MgCl2 solution under the laboratory conditions. The C 1010 exhibited the highest percentage of rust area and suffered the most weight loss as a result of field exposure and MgCl2 sprays. In terms of ultimate tensile strength, the Al 1100 coupons saw the greatest reduction and the unstressed and externally stressed SS 304 coupons saw the least. The ability of MgCl2 to penetrate deep into the matrix of aluminum alloy poses great risk to such structural material. Tensile stressed SS 304 suffered more corrosion than unstressed SS 304 in both the field and laboratory conditions. Results from this case study may shed new light on the deicer corrosion issue and help develop improved field testing methods to evaluate the deicer corrosivity to metals in service.

  1. A MULTIWAVELENGTH STUDY OF TADPOLE GALAXIES IN THE HUBBLE ULTRA DEEP FIELD

    International Nuclear Information System (INIS)

    Straughn, Amber N.; Eufrasio, Rafael T.; Gardner, Jonathan P.; Voyer, Elysse N.; Mello, Duilia de; Soto, Emmaris; Petty, Sara; Kassin, Susan; Ravindranath, Swara

    2015-01-01

    Multiwavelength data are essential in order to provide a complete picture of galaxy evolution and to inform studies of galaxies’ morphological properties across cosmic time. Here we present the results of a multiwavelength investigation of the morphologies of “tadpole” galaxies at intermediate redshift (0.314 < z < 3.175) in the Hubble Ultra Deep Field. These galaxies were previously selected from deep Hubble Space Telescope (HST) F775W data based on their distinct asymmetric knot-plus-tail morphologies. Here we use deep Wide Field Camera 3 near-infrared imaging in addition to the HST optical data in order to study the rest-frame UV/optical morphologies of these galaxies across the redshift range 0.3 < z < 3.2. This study reveals that the majority of these galaxies do retain their general asymmetric morphology in the rest-frame optical over this redshift range, if not the distinct “tadpole” shape. The average stellar mass of tadpole galaxies is lower than that of field galaxies, with the effect being slightly greater at higher redshift within the errors. Estimated from spectral energy distribution fits, the average age of tadpole galaxies is younger than that of field galaxies in the lower-redshift bin, and the average metallicity is lower (whereas the specific star formation rate for tadpoles is roughly the same as field galaxies across the redshift range probed here). These average effects combined support the conclusion that this subset of galaxies is in an active phase of assembly, either late-stage merging or cold gas accretion causing localized clumpy star formation

  2. Properties and cleanability of new and traditional surface materials in cattle barns - a field study

    Directory of Open Access Journals (Sweden)

    R. KUISMA

    2008-12-01

    Full Text Available In this study surface properties and cleanability of new and traditional surface materials in cattle barns were examined in a field test. The concrete and plastic-coated samples were placed on a walking path on the floor and on a feeding table in a cattle barn. The surfaces were characterized using colorimetric and gloss measurements and determination of topography. In most cases, the colour of the surfaces placed on the floor darkened during the one year study period, whereas the colour changes of the samples placed on the feeding table did not show a similar trend. However, in both locations the plastic-coated surfaces were generally the easiest to clean, and the highest colour changes indicating soil residues were detected on the uncoated and silane-impregnated concrete surfaces. The difference between the locations was also seen in the gloss values, which increased in the samples placed on the floor during the one-year test period but varied considerably between the different materials on the surfaces placed on the feeding table. This field study confirmed the observation from earlier laboratory studies that plastic coatings improved the cleanability of concrete cattle barn surfaces. Silane impregnation was not functionally competitive with the plastic coatings. In general, the cleanability results were in accordance with the results of previous laboratory experiments but the field study provided practical information about the behaviour of the surface materials examined.;

  3. Advancing the field of organizations through the study of military organizations

    DEFF Research Database (Denmark)

    Augier, Mie; Knudsen, Torbjorn; McNab, Robert M.

    2014-01-01

    This article argues that the field of organization studies may learn from closer study of decision-making and behaviors in military organizations. It describes some of the intellectual roots of organizational studies within a strategic, military context; discusses some recent characteristics...... of strategic competition that organization scholars may find fruitful to study; and view some of the key contemporary challenges in military organizations through the lens of strategic organization design, a framework the builds on, and integrates, several streams of research in organizational behavior...... that have implications for, and influence, how organizations make strategic decisions....

  4. A Study on the Field Data Communication Structure under Harsh Environment in Nuclear Power Plants

    International Nuclear Information System (INIS)

    Hur, Seop; Hong, S. B.; Lee, J. K.; Kim, D. H.; Chung, K. I.; Kim, C. H.; Koo, I. S.; Cho, J. W.; Lee, J. C.; Choi, Y. S.

    2009-01-01

    As digitizing the I and C systems in nuclear plants, The SMART sensors/ actuators are considered as a alternative of the conventional field devices. Because the digitization of the filed level devises is still primitive, it is necessary to perform the relative R and D. Especially, it is difficult to adopt the digital devices in a containment building of the nuclear plants due to the harsh environment conditions such as high level radiation and high temperature. Considering the tendency of the reliability enhancement, from now on, the digital device will be adopted in the harsh environment. The major technical issues of the field level digitization are a SMART transmitter/actuator technology, a network technology and an equipment qualification in harsh environment. This report describes the study results regarding the field level data network. There are many merits such as an automatic test, a diagnostics and auto-calibration when digitizing of the I and C systems. While, the data capacity will be much increased compare to the conventional systems. The future field data network should have larger data transmission speed compare to the current sensor networks such as HART and deviceNET. The candidate commercial network has been selected considering the nuclear requirements. Based on the this network, a protocol structure and a access control structure are recommended. Instruments in containment building are analyzed and the design bases and requirements have been setup to assure the safety and performance of the field data communication. According to the design bases, requirements and the node allocation criteria, the field network has been divided by functional segmentation and each instrument has been allocated to each individual data network

  5. Dosimetric characterization of small fields using a plastic scintillator detector: A large multicenter study.

    Science.gov (United States)

    Mancosu, Pietro; Pasquino, Massimo; Reggiori, Giacomo; Masi, Laura; Russo, Serenella; Stasi, Michele

    2017-09-01

    In modern radiation therapy accurate small fields dosimetry is a challenge and its standardization is fundamental to harmonize delivered dose in different institutions. This study presents a multicenter characterization of MLC-defined small field for Elekta and Varian linear accelerators. Measurements were performed using the Exradin W1 plastic scintillator detector. The project enrolled 24 Italian centers. Each center performed Tissue Phantom Ratio (TPR), in-plane and cross-plane dose profiles of 0.8×0.8cm 2 field, and Output Factor (OF) measurements for square field sizes ranging from 0.8 to 10cm. Set-up conditions were 10cm depth in water phantom at SSD 90cm. Measurements were performed using two twin Exradin W1 plastic scintillator detectors (PSD) correcting for the Cerenkov effect as proposed by the manufacturer. Data analysis from 12 Varian and 12 Elekta centers was performed. Measurements of 7 centers were not included due to cable problems. TPR measurements showed standard deviations (SD)<1%; SD<0.4mm for the profile penumbra was obtained, while FWHM measurements showed SD<0.5mm. OF measurements showed SD<1.5% for field size greater than 2×2cm 2 . Median OFs values were in agreement with the recent bibliography. High degree of consistency was registered for all the considered parameters. This work confirmed the importance of multicenter dosimetric intercomparison. W1 PSD could be considered as a good candidate for small field measurements. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  6. The Comparison of Iranian and Foreign Students’ Motivations to Choose Dentistry Field of Study

    Directory of Open Access Journals (Sweden)

    Abdolreza Gilavand

    2016-06-01

    Full Text Available Background Because of some special and privileged attractions of dentistry discipline, the first choice of volunteers who want to enter university is dentistry. The students usually choose it regardless to their interests and talents. Therefore, this study aimed to investigate Iranian and Foreign student’s motivations to choose dentistry field of study. Materials and Methods We searched international databases such as PubMed, Scopus, EMBASE, Cochrane Library, and Iranian databases such as SID, Magiran, Iranmedex using a searching strategy during 2000 to 2015 years. Database without language restriction, since 2000 sources, with the MeSH term "Choose dentistry field" AND "Students". At first, in the initial search,152 articles were found, and finally, 51 of them which were related to the subject of this research were used. Results In general, the motivation of students to choose field of study in Iranain and Foreign students include the following:: an independent office or job independence, high economic income, appropriate social status,  job attractiveness of dentistry, appropriate job position, individual longing, help others, top rank of student in the university entrance exam, continue to study at specialized PhD in one of dentistry trends, successful marriage nd interest in the field of dentistry. Conclusion It seems that with regard to the high unemployment rate of university graduates in Iran, the most important incentives of applicants who want to enter the dentistry discipline are high income and  particular social prestige at this major. Moreover, high income and independent job situations are the most important factors in Foreign students for choosing this filed of study in the overseas studies.

  7. Impact of field of study, college and year on calculation of cumulative grade point average.

    Science.gov (United States)

    Trail, Carla; Reiter, Harold I; Bridge, Michelle; Stefanowska, Patricia; Schmuck, Marylou; Norman, Geoff

    2008-08-01

    A consistent finding from many reviews is that undergraduate Grade Point Average (uGPA) is a key predictor of academic success in medical school. Curiously, while uGPA has established predictive validity, little is known about its reliability. For a variety of reasons, medical schools use different weighting schemas to combine years of study. Additional concerns relate to the equivalence of grades obtained from different fields of study and institutions, with little hard data to guide conclusions. At the Michael G. DeGroote School of Medicine Class of 2007 at McMaster University, every undergraduate grade of 2,138 applicants, along with field of study and post-secondary educational institution, was analyzed. Individual grades were aggregated into an overall uGPA using published algorithms from several medical school, and correlated with a non-weighted sum. Correlations of the different schemas with equal weights ranged from 0.973 to 0.990. The extent of the difference between fields of study was small, accounting for only 1.5% of the variance. However, differences among 16 Ontario universities were larger, and accounted for 9.3% of the variance. The results of this study suggest that all weighting schemas are virtually equivalent, making any formulation reasonable. Differences by field of study are small, but do not show any bias against non-science students. Differences by institution are larger, amounting to a range in average score from 78.7 to 84.6; however it is not clear whether this reflects candidate ability or institutional policy, so attempts to correct for institution may be difficult.

  8. Pilot study of extremely low frequency magnetic fields emitted by transformers in dwellings. Social aspects.

    Science.gov (United States)

    Zaryabova, Victoria; Shalamanova, Tsvetelina; Israel, Michel

    2013-06-01

    A large number of epidemiologic studies examining the potential effect of residential exposure to extremely-low frequency (ELF) magnetic fields and childhood leukemia have been published. Two pooled analyses [Ahlbom A, Day N, Feychting M, Roman E, Skinner J, Dockerty J, Linet M, et al. (2000). A pooled analysis of magnetic fields and childhood leukaemia. Br J Cancer. 83(5):692-698; Greenland S, Sheppard AR, Kaune WT, Poole C, Kelsh AM (2000). A pooled analysis of magnetic fields, wire codes, and childhood leukemia. Epidemiology. 11(6):624-634], which included the major epidemiologic studies on ELF magnetic fields and childhood leukemia showed twofold increase in childhood leukemia risk in association with residential ELF exposure above 0.3-0.4 μT. Based on "limited" epidemiologic evidence linking ELF exposure to childhood leukemia and "inadequate evidence" for carcinogenicity of ELF in rodent bioassays, the International Agency for Research on Cancer (IARC) classified ELF magnetic fields as a possible human carcinogen (2B classification) [International Agency for Research on Cancer (IARC) (2002). Non-ionizing radiation, Part 1: Static and extremely low-frequency (ELF) electric and magnetic fields. IARC monographs on the evaluation of carcinogenic risks to humans. Vol. 80. IARC Press: Lyon], confirmed by WHO on the basis of studies published after 2000 [World Health Organization. Extremely low frequency fields. In: 238 Environmental health criteria, Geneva: WHO; 2007]. The analysis of more recent studies of ELF magnetic fields and childhood leukemia had small findings and propose methodological improvements concerning the uncertainties in epidemiological approaches and exposure assessment, bias in selection of controls [Kheifets L, Oksuzyan S (2008). Exposure assessment and other challenges in non-ionizing radiation studies of childhood leukaemia. Radiat Prot Dosimetry. 132(2):139-147]. By the end of 2010, 37 countries had been identified for possible participation

  9. Child leukemia and magnetic fields in Japan: a study on the child leukemia and residential exposure to power-frequency magnetic fields in Japan

    International Nuclear Information System (INIS)

    Souques, M.

    2006-01-01

    A new study on the relationship between the exposure to magnetic fields 50/60 hz and the leukemia risk for child, realised in Japan, has just been published. The results show an increase of the risk for the exposure over to .4 μ T, but the interval of confidence shows that this study has a lack of power for the statistical analysis. Finally, this study cannot claims to bring contribution to the scientific debate about the low frequency magnetic fields. (N.C.)

  10. Quantitative approach to skin field cancerization using a nanoencapsulated photodynamic therapy agent: a pilot study

    Directory of Open Access Journals (Sweden)

    Passos SK

    2013-02-01

    Full Text Available Simone K Passos,1,2 Paulo EN de Souza,3 Priscila KP Soares,1,3 Danglades RM Eid,1,2 Fernando L Primo,4 Antonio Cláudio Tedesco,4 Zulmira GM Lacava,1 Paulo C Morais3,51University of Brasília, Institute of Biological Sciences, DF, Brazil; 2Foundation for Teaching and Research on Health Sciences, Brasília, DF, Brazil; 3University of Brasília, Institute of Physics, Brasília, DF, Brazil; 4Department of Chemistry, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, Laboratory of Photobiology and Photomedicine, University of São Paulo, Ribeirão Preto, São Paulo, Brazil; 5Department of Control Science and Engineering, Hua-Zhong University of Science and Technology, Wuham, People's Republic of ChinaBackground: This paper introduces a new nanoformulation of 5-aminolevulinic acid (nano-ALA as well as a novel quantitative approach towards evaluating field cancerization for actinic keratosis and/or skin photodamage. In this pilot study, we evaluated field cancerization using nano-ALA and methyl aminolevulinate (MAL, the latter being commercialized as Metvix®.Methods and results: Photodynamic therapy was used for the treatment of patients with selected skin lesions, whereas the fluorescence of the corresponding photosensitizer was used to evaluate the time evolution of field cancerization in a quantitative way. Field cancerization was quantified using newly developed color image segmentation software. Using photodynamic therapy as the precancer skin treatment and the approach introduced herein for evaluation of fluorescent area, we found that the half-life of field cancerization reduction was 43.3 days and 34.3 days for nano-ALA and MAL, respectively. We also found that nano-ALA targeted about 45% more skin lesion areas than MAL. Further, we found the mean reduction in area of skin field cancerization was about 10% greater for nano-ALA than for MAL.Conclusion: Although preliminary, our findings indicate that the efficacy of nano-ALA in

  11. Geometry of nutrition in field studies: an illustration using wild primates.

    Science.gov (United States)

    Raubenheimer, David; Machovsky-Capuska, Gabriel E; Chapman, Colin A; Rothman, Jessica M

    2015-01-01

    Nutritional geometry has shown the benefits of viewing nutrition in a multidimensional context, in which foraging is viewed as a process of balancing the intake and use of multiple nutrients. New insights into nutrient regulation have been generated in studies performed in a laboratory context, where accurate measures of amounts (e.g. eaten, converted to body mass, excreted) can be made and analysed using amounts-based nutritional geometry. In most field situations, however, proportional compositions (e.g. of foods, diets, faeces) are the only measures readily available, and in some cases are more relevant to the problem at hand. For this reason, a complementary geometric method was recently introduced for analysing multi-dimensional data on proportional compositions in nutritional studies, called the right-angled mixture triangle (RMT). We use literature data from field studies of primates to demonstrate how the RMT can provide insight into a variety of important concepts in nutritional ecology. We first compare the compositions of foods, using as an example primate milks collected in both the wild and the laboratory. We next compare the diets of different species of primates from the same habitat and of the same species (mountain gorillas) from two distinct forests. Subsequently, we model the relationships between the composition of gorilla diets in these two habitats and the foods that comprise these diets, showing how such analyses can provide evidence for active nutrient-specific regulation in a field context. We provide a framework to relate concepts developed in laboratory studies with field-based studies of nutrition.

  12. International student Arctic Field School on Permafrost and urban areas study

    Science.gov (United States)

    Suter, L.; Tolmanov, V. A.; Grebenets, V. I.; Streletskiy, D. A.; Shiklomanov, N. I.

    2017-12-01

    Arctic regions are experiencing drastic climatic and environmental changes. These changes are exacerbated in the Russian Arctic, where active resource development resulted in further land cover transformations, especially near large settlements. There is a growing need in multidisciplinary studies of climate and human- induced changes in the Arctic cities. In order to fill this gap, International Arctic Field Course on Permafrostand Northern Studies was organized in July 2017 to the Russian Arctic. The course was organized under the umbrella of the Arctic PIRE project in cooperation between the George Washington University, Moscow State University, and the Russian Center for Arctic Development. The course attracted twenty undergraduate and graduate students from Russia, USA, and EU countries and involved instructors specializing in Arctic system science, geocryology, permafrost engineering, and urban sustainability. The field course was focused on studying typical natural Arctic landscapes of tundra and forest tundra; transformations of natural landscapes in urban and industrial areas around Vorkuta and Salekhard; construction and planning on permafrost and field methods and techniques, including permafrost and soil temperature monitoring, active layer thickness (ALT) measurements, studying of cryogenic processes, stratigraphic and soil investigations, vegetation and microclimate studies. The students were also engaged in a discussion of climatic change and historical development of urban areas on permafrost,and were exposed to examples of both active and passive construction principles while conducting a field survey of permafrost related building deformations. During the course, students collected more than 800 ALT and soil temperature measurements in typical landscapes around Vorkuta and Salekhard to determine effects of soil and vegetation factors on ground thermal regime; surveyed several hundreds of buildings to determine locations with most deformation

  13. Experimental study of flow field characteristics on bed configurations in the pebble bed reactor

    International Nuclear Information System (INIS)

    Jia, Xinlong; Gui, Nan; Yang, Xingtuan; Tu, Jiyuan; Jia, Haijun; Jiang, Shengyao

    2017-01-01

    Highlights: • PTV study of flow fields of pebble bed reactor with different configurations are carried out. • Some criteria are proposed to quantify vertical velocity field and flow uniformity. • The effect of different pebble bed configurations is also compared by the proposed criteria. • The displacement thickness is used analogically to analyze flow field characteristics. • The effect of mass flow variation in the stagnated region of the funnel flow is measured. - Abstract: The flow field characteristics are of fundamental importance in the design work of the pebble bed high temperature gas cooled reactor (HTGR). The different effects of bed configurations on the flow characteristics of pebble bed are studied through the PTV (Particle Tracking Velocimetry) experiment. Some criteria, e.g. flow uniformity (σ) and mass flow level (α), are proposed to estimate vertical velocity field and compare the bed configurations. The distribution of the Δθ (angle difference between the individual particle velocity and the velocity vector sum of all particles) is also used to estimate the resultant motion consistency level. Moreover, for each bed configuration, the thickness of displacement is analyzed to measure the effect of the funnel flow zone based on the boundary layer theory. Detailed information shows the quantified characteristics of bed configuration effects on flow uniformity and other characteristics; and the sequence of levels of each estimation criterion is obtained for all bed configurations. In addition, a good design of the pebble bed configuration is suggested and these estimation criteria can be also applied and adopted in testing other geometry designs of pebble bed.

  14. Study of Fluid Flow Control in Protein Crystallization using Strong Magnetic Fields

    Science.gov (United States)

    Ramachandran, Narayanan; Leslie, Fred; Ciszak, Ewa

    2002-01-01

    positioning the crystal growth cell so that the magnetic susceptibility force counteracts terrestrial gravity. The general objective is to test the hypothesis of convective control using a strong magnetic field and magnetic field gradient and to understand the nature of the various forces that come into play. Specifically we aim to delineate causative factors and to quantify them through experiments, analysis and numerical modeling. Once the basic understanding is obtained, the study will focus on testing the hypothesis on proteins of pyruvate dehydrogenase complex (PDC), proteins E1 and E3. Obtaining high crystal quality of these proteins is of great importance to structural biologists since their structures need to be determined. Specific goals for the investigation are: 1. To develop an understanding of convection control in diamagnetic fluids with concentration gradients through experimentation and numerical modeling. Specifically solutal buoyancy driven convection due to crystal growth will be considered. 2. To develop predictive measures for successful crystallization in a magnetic field using analyses and numerical modeling for use in future protein crystal growth experiments. This will establish criteria that can be used to estimate the efficacy of magnetic field flow damping on crystallization of candidate proteins. 3. To demonstrate the understanding of convection damping by high magnetic fields to a class of proteins that is of interest and whose structure is as yet not determined. 4. To compare quantitatively, the quality of the grown crystals with and without a magnetic field. X-ray diffraction techniques will be used for the comparative studies. In a preliminary set of experiments, we studied crystal dissolution effects in a 5 Tesla magnet available at NASA Marshall Space Flight Center (MSFC). Using a Schlieren setup, a 1mm crystal of Alum (Aluminum-Potassium Sulfate) was introduced in a 75% saturated solution and the resulting dissolution plume was observed

  15. Field Artillery Ammunition Processing System (FAAPS) concept evaluation study. Ammunition Logistics Program

    Energy Technology Data Exchange (ETDEWEB)

    Kring, C.T.; Babcock, S.M.; Watkin, D.C.; Oliver, R.P.

    1992-06-01

    The Field Artillery Ammunition Processing System (FAAPS) is an initiative to introduce a palletized load system (PLS) that is transportable with an automated ammunition processing and storage system for use on the battlefield. System proponents have targeted a 20% increase in the ammunition processing rate over the current operation while simultaneously reducing the total number of assigned field artillery battalion personnel by 30. The overall objective of the FAAPS Project is the development and demonstration of an improved process to accomplish these goals. The initial phase of the FAAPS Project and the subject of this study is the FAAPS concept evaluation. The concept evaluation consists of (1) identifying assumptions and requirements, (2) documenting the process flow, (3) identifying and evaluating technologies available to accomplish the necessary ammunition processing and storage operations, and (4) presenting alternative concepts with associated costs, processing rates, and manpower requirements for accomplishing the operation. This study provides insight into the achievability of the desired objectives.

  16. Ambipolar electric fields and turbulence studies in the Wisconsin levitated toroidal octupole

    International Nuclear Information System (INIS)

    Armentrout, C.J.

    1977-01-01

    Detailed studies of hot ion plasmas (T/sub i/ > T/sub e/) in the poloidal field octupole show that the ambipolar electric field which is perpendicular to the flux surfaces is well explained by the observed properties of the microturbulence structures in the plasma. The turbulence structure has been measured by correlation techniques which are carefully described. In these experiments, signals were studied which are aperiodic in time and space, short lived compared to the decay times of the bulk plasma parameters, short ranged compared to the machine size, and are therefore classified as microturbulence structures. The resulting spatial and temporal correlation functions (CFs) are well fitted to a Gaussian function and the associated correlation lengths or times are the half width at half maximum of the CFs. The correlation length is measured to be the ion gyro radius for the hot hydrogen plasma and somewhat less for the helium plasma

  17. A CFD Study on Inlet Plenum Flow Field of Pebble Bed Reactor

    International Nuclear Information System (INIS)

    Kim, Min Hwan; Lee, Won Jae; Chang, Jong Hwa

    2005-01-01

    High temperature gas cooled reactor, largely divided into two types of PBR (Pebble Bed Reactor) and PMR (Prismatic Modular Reactor), has becomes great interest of researchers in connection with the hydrogen production. KAERI has started a project to develop the gas cooled reactor for the hydrogen production and has been doing in-depth study for selecting the reactor type between PBR and PMR. As a part of the study, PBMR (Pebble Bed Modular Reactor) was selected as a reference PBR reactor for the CFD analysis and the flow field of its inlet plenum was simulated with computational fluid dynamics program CFX5. Due to asymmetrical arrangement of pipes to the inlet plenum, non-uniform flow distribution has been expected to occur, giving rise to non-uniform power distribution at the core. Flow fields of different arrangement of inlet pipes were also investigated, as one of measures to reduce the non-uniformity

  18. Tokamak Fusion Core Experiment: design studies based on superconducting and hybrid toroidal field coils. Design overview

    Energy Technology Data Exchange (ETDEWEB)

    Flanagan, C.A. (ed.)

    1984-10-01

    This document is a design overview that describes the scoping studies and preconceptual design effort performed in FY 1983 on the Tokamak Fusion Core Experiment (TFCX) class of device. These studies focussed on devices with all-superconducting toroidal field (TF) coils and on devices with superconducting TF coils supplemented with copper TF coil inserts located in the bore of the TF coils in the shield region. Each class of device is designed to satisfy the mission of ignition and long pulse equilibrium burn. Typical design parameters are: major radius = 3.75 m, minor radius = 1.0 m, field on axis = 4.5 T, plasma current = 7.0 MA. These designs relay on lower hybrid (LHRH) current rampup and heating to ignition using ion cyclotron range of frequency (ICRF). A pumped limiter has been assumed for impurity control. The present document is a design overview; a more detailed design description is contained in a companion document.

  19. Study of Wood Plastic Composites elastic behaviour using full field measurements

    Directory of Open Access Journals (Sweden)

    Graciaa A.

    2010-06-01

    Full Text Available In this study, the mechanical properties and microstructure of HDPE/wood fibre composites are investigated. The four-point bending and tensile behaviour of Wood Plastic Composite (WPC with or without additive are studied by using full-field strain measurements by 3-D Digital Image Correlation (3-D DIC. A non-linear behaviour is shown. The modulus of elasticity (MOE is calculated as the tangent at zero strain of a Maxwell-Bingham model fitted onto experimental data. Four-point bending tests are analyzed thanks to the spatial standard deviation of the longitudinal strain field to determine the degree of heterogeneity. Cyclic tensile tests have been performed in order to analyze the damage of the material. Moreover, Scanning Electron Microscope (SEM is used to characterize the morphology of the wood fibre/HDPE matrix interface for specimens with maleic anhydride modified polyethylene additive (MAPE.

  20. Study of Wood Plastic Composites elastic behaviour using full field measurements

    Science.gov (United States)

    Ben Mbarek, T.; Robert, L.; Hugot, F.; Orteu, J. J.; Sammouda, H.; Graciaa, A.; Charrier, B.

    2010-06-01

    In this study, the mechanical properties and microstructure of HDPE/wood fibre composites are investigated. The four-point bending and tensile behaviour of Wood Plastic Composite (WPC) with or without additive are studied by using full-field strain measurements by 3-D Digital Image Correlation (3-D DIC). A non-linear behaviour is shown. The modulus of elasticity (MOE) is calculated as the tangent at zero strain of a Maxwell-Bingham model fitted onto experimental data. Four-point bending tests are analyzed thanks to the spatial standard deviation of the longitudinal strain field to determine the degree of heterogeneity. Cyclic tensile tests have been performed in order to analyze the damage of the material. Moreover, Scanning Electron Microscope (SEM) is used to characterize the morphology of the wood fibre/HDPE matrix interface for specimens with maleic anhydride modified polyethylene additive (MAPE).

  1. Low frequency electromagnetic fields in Switzerland and in Germany. Comprehensive report on various studies

    International Nuclear Information System (INIS)

    Stratmann, M.; Wernli, C.; Grigat, J. P.; Eisenbrandt, H.

    1998-01-01

    The work of two research groups has been combined in this report. Both groups have concerned themselves with the occurrence and the distribution of low-frequency magnetic fields in the human environment. The initiative for the joint documentation came from the Radiation Metrology Section of the Paul Scherrer Institute. This team has investigated the general exposure on the Swiss population due to 50 Hz magnetic fields and the exposure arising from 162/3 Hz magnetic fields in the passenger area of trains. In addition, source-related measurements and frequency analyses up to 200 kHz have been undertaken. As a second group, the 'Research Association: Electromagnetic tolerance of biological systems' of the Technical University of Braunschweig, under the direction of Prof. Karl Brinkmann, has participated in the preparation of this documentation. During the past years, the research association has prepared two extensive studies on the local and temporal distribution of magnetic field sources in human residential areas and has contributed its findings on the residential situation as a supplement to the treatment of the problems described here. Intentionally, the report has not been prepared as a scientific presentation, but rather as informative reading for specialists as well as for the general public. (author)

  2. Study of microparticles' anomalous diffusion in active bath using speckle light fields (Presentation Recording)

    Science.gov (United States)

    Pince, Ercag; Sabareesh, Sabareesh K. P.; Volpe, Giorgio; Gigan, Sylvain; Volpe, Giovanni S.

    2015-08-01

    Particles undergoing a stochastic motion within a disordered medium is a ubiquitous physical and biological phenomenon. Examples can be given from organelles as molecular machines of cells performing physical tasks in a populated cytoplasm to human mobility in patchy environment at larger scales. Our recent results showed that it is possible to use the disordered landscape generated by speckle light fields to perform advanced manipulation tasks at the microscale. Here, we use speckle light fields to study the anomalous diffusion of micron size silica particles (5 μm) in the presence of active microswimmers. The microswimmers we used in the experiments are motile bacteria, Escherichia coli (E.coli). They constitute an active background constantly agitating passive silica particles within complex optical potentials. The speckle fields are generated by mode mixing inside a multimode optical fiber where a small amount of incident laser power (maximum power = 12 μW/μm2) is needed to obtain an effective random landscape pattern for the purpose of optical manipulation. We experimentally show how complex potentials contribute to the anomalous diffusion of silica particles undergoing collisions with swimming bacteria. We observed an enhanced diffusion of particles interacting with the active bath of E.coli inside speckle light fields: this effect can be tuned and controlled by varying the intensity and the statistical properties of the speckle pattern. Potentially, these results could be of interest for many technological applications, such as the manipulation of microparticles inside optically disordered media of biological interests.

  3. Experimental and theoretical study on field emission properties of zinc oxide nanoparticles decorated carbon nanotubes

    International Nuclear Information System (INIS)

    Li Xin; Zhou Wei-Man; Liu Wei-Hua; Wang Xiao-Li

    2015-01-01

    Field emission properties of zinc oxide (ZnO) nanoparticles (NPs) decorated carbon nanotubes (CNTs) are investigated experimentally and theoretically. CNTs are in situ decorated with ZnO NPs during the growth process by chemical vapor deposition using a carbon source from the iron phthalocyanine pyrolysis. The experimental field emission test shows that the ZnO NP decoration significantly improves the emission current from 50 μA to 275 μA at 550 V and the reduced threshold voltage from 450 V to 350 V. The field emission mechanism of ZnO NPs on CNTs is theoretically studied by the density functional theory (DFT) combined with the Penn–Plummer method. The ZnO NPs reconstruct the ZnO–CNT structure and pull down the surface barrier of the entire emitter system to 0.49 eV so as to reduce the threshold electric field. The simulation results suggest that the presence of ZnO NPs would increase the LDOS near the Fermi level and increase the emission current. The calculation results are consistent with the experiment results. (paper)

  4. Large-field high-resolution x-ray microscope for studying laser plasmas

    International Nuclear Information System (INIS)

    Sauneuf, R.; Dalmasso, J.; Jalinaud, T.; Le Breton, J.; Schirmann, D.; Marioge, J.; Bridou, F.; Tissot, G.; Clotaire, J.

    1997-01-01

    In 1948, P. Kirkpatrick and A. V. Baez developed an x-ray microscope (energy range about 100 eV endash 10 keV) composed of two concave spherical mirrors working at grazing incidence. That device, named KB microscope, presents a 3 endash 5 μm resolution within a field having a radius about 100 μm; outside that field, its resolution lowers rapidly when the object point recedes from the center. The adjunction of two similar mirrors can notably increase the useful field (typically, the resolution can be better than 10 μm within a 2-mm-diam field of view), which is necessary for studying laser plasmas. Its main advantage with respect to more simple optics, as the pinhole, is that it can be located far enough from the plasma to avoid any destruction during the shot. We describe such a microscope that we call KBA microscope and present some images of fine metallic grids. Those grids were backlighted by x-ray sources, either a cw one or a series of laser plasmas from the Octal endash Hacute eliotrope facility. Examining the films in detail shows that the experimental results are very close to the theoretical characteristics; hence the interest of this device for the x-ray diagnostics on the future powerful laser facilities. copyright 1997 American Institute of Physics

  5. Project Overview: Cumulus Humilis Aerosol Processing Study (CHAPS): Proposed Summer 2007 ASP Field Campaign

    Energy Technology Data Exchange (ETDEWEB)

    Berkowitz, Carl M.; Berg, Larry K.; Ogren, J. A.; Hostetler, Chris A.; Ferrare, Richard

    2006-05-18

    This white paper presents the scientific motivation and preliminary logistical plans for a proposed ASP field campaign to be carried out in the summer of 2007. The primary objective of this campaign is to use the DOE Gulfstream-1 aircraft to make measurements characterizing the chemical, physical and optical properties of aerosols below, within and above large fields of fair weather cumulus and to use the NASA Langley Research Center’s High Spectral Resolution Lidar (HSRL) to make independent measurements of aerosol backscatter and extinction profiles in the vicinity of these fields. Separate from the science questions to be addressed by these observations will be information to add in the development of a parameterized cumulus scheme capable of including multiple cloud fields within a regional or global scale model. We will also be able to compare and contrast the cloud and aerosol properties within and outside the Oklahoma City plume to study aerosol processes within individual clouds. Preliminary discussions with the Cloud and Land Surface Interaction Campaign (CLASIC) science team have identified overlap between the science questions posed for the CLASIC Intensive Operation Period (IOP) and the proposed ASP campaign, suggesting collaboration would benefit both teams.

  6. Vadose Zone Transport Field Study: Detailed Test Plan for Simulated Leak Tests

    Energy Technology Data Exchange (ETDEWEB)

    Ward, Anderson L.; Gee, Glendon W.

    2000-06-23

    This report describes controlled transport experiments at well-instrumented field tests to be conducted during FY 2000 in support of DOE?s Vadose Zone Transport Field Study (VZTFS). The VZTFS supports the Groundwater/Vadose Zone Integration Project Science and Technology Initiative. The field tests will improve understanding of field-scale transport and lead to the development or identification of efficient and cost-effective characterization methods. These methods will capture the extent of contaminant plumes using existing steel-cased boreholes. Specific objectives are to 1) identify mechanisms controlling transport processes in soils typical of the hydrogeologic conditions of Hanford?s waste disposal sites; 2) reduce uncertainty in conceptual models; 3) develop a detailed and accurate data base of hydraulic and transport parameters for validation of three-dimensional numerical models; and 4) identify and evaluate advanced, cost-effective characterization methods with the potential to assess changing conditions in the vadose zone, particularly as surrogates of currently undetectable high-risk contaminants. Pacific Northwest National Laboratory (PNNL) manages the VZTFS for DOE.

  7. Reduction of cardiac volume in left-breast treatment fields by respiratory maneuvers: a CT study

    International Nuclear Information System (INIS)

    Lu, H.-M.; Cash, Ethan; Chen, M.-H.; Chin Lee; Manning, Warren J.; Harris, Jay; Bornstein, Bruce

    2000-01-01

    Purpose: A previous study of healthy female volunteers suggested that deep inspiratory breath holding can reduce the cardiac volume in the treatment portals for left-breast cancer treatment. The reduction of irradiated cardiac volume may be important considering the reported late cardiac morbidity and mortality and the frequent coexistent use of potentially cardiotoxic chemotherapy in breast cancer patients. In the present study, we evaluated the heart volume in the fields and, thus, the true benefit of this respiratory maneuver in breast cancer patients undergoing CT simulation. Materials and Methods: Fifteen patients (median age, 53) were studied. For each patient, CT scans were performed both when the patient breathed normally (quiet respiration) and when the patient held her breath after a deep inspiration. Tangential fields were planned using the same medial, lateral, superior, and inferior borders on skin for the normal breathing and the breath-holding configurations. The cardiac and left-lung volumes within the tangential fields were calculated for both breathing configurations. Multiple scan series were performed for the breath-holding configuration to provide a more accurate delineation of the cardiac tissue and to study the reproducibility of the patient's position between different cycles of deep inspiration. Results: None of the patients had difficulty holding her breath for 20 s. The cardiac volume in the field was reduced (-86 ± 24%; p 3 vs 97 cm 3 , p < 0.001). However, the fractional volume of the left lung in the field was essentially unchanged. For all but 1 patient, the maximum difference between the external body contours from different breath holding cycles was 5 mm and occurred at the lateral aspect of the breast. At the medial aspect, as indicated by the position of the midline marker, the variations were well within the currently accepted tolerance for patient positioning during tangential treatment. Conclusions: Deep-inspiration breath

  8. Field Study of a Physical Game for Older Adults Based on an Autonomous, Mobile Robot

    DEFF Research Database (Denmark)

    Hansen, Søren Tranberg; Rasmussen, Dorte Malig; Bak, Thomas

    2012-01-01

    This paper presents an initial, qualitative study on how a game based on a mobile robot with an expressive head can be used as a physical activity for elderly. The game is investigated in two independent field studies - one in a nursing home and one in a rehabilitation centre for elderly using...... an open, exploratory approach. An analysis of the interaction is made based on video recordings, observations and qualitative interviews focusing on the potential of the robot as a rehabilitative application. The primary goal of the study is to observe seniors’ acceptance of the robot, to obtain knowledge...... about their game play patterns and get ideas about future improvements of the game....

  9. Field Studies: Novels as Darwinian Niches, Poetry for Physicists and Mathematicians

    Directory of Open Access Journals (Sweden)

    Daniel Walter Brown

    2010-10-01

    Full Text Available This brief forum contribution reflects upon some historical factors in the formation of nineteenth century science and of the literature and science discipline that has since arisen to study its literary receptions. Noting the preponderance of studies focusing upon forms of scientific developmentalism, principally Darwinian biology, and of novels and other prose, and more broadly, on literary figures, rather than the writings of scientists, the paper introduces some poetry on science by scientists. It concentrates principally on those working and writing in the fields of physics and mathematics, areas that have been neglected in literature and science studies.

  10. Work-Team Implementation and Trajectories of Manufacturing Quality: A Longitudinal Field Study

    OpenAIRE

    Rajiv D. Banker; Joy M. Field; Kingshuk K. Sinha

    2001-01-01

    The study examines the sustainability of manufacturing quality improvements following the implementation of work teams on production lines. We posit that the impact on manufacturing quality, measured as the defect rate trajectory, is monotonically nonincreasing over time and may, more specifically, assume the shape of an inverted S-curve. Employing a longitudinal research design, we investigate four work teams over a 28-month period in a field setting. Each team corresponds to one of the four...

  11. Final report for the field-reversed configuration power plant critical-issue scoping study

    Energy Technology Data Exchange (ETDEWEB)

    Santarius, John F.; Mogahed, Elsayed A.; Emmert, Gilbert A.; Khater, Hesham Y.; Nguyen, Canh N.; Ryzhkov, Sergei V.; Stubna, Michael D.; Steinhauer, Loren C.; Miley, George H.

    2001-03-01

    This report describes research in which a team from the Universities of Wisconsin, Washington, and Illinois performed a scoping study of critical issues for field-reversed configuration (FRC) power plants. The key tasks for this research were (1) systems analysis of deuterium-tritium (D-T) FRC fusion power plants, and (2) conceptual design of the blanket and shield module for an FRC fusion core.

  12. The self-consistent field method in the study of many-body problems

    International Nuclear Information System (INIS)

    Campos, V.B.F. de.

    1976-01-01

    Properties of many-body systems in special quantum liquids (T=O 0 K), utilizing the self-consistent field method (SCFM) are calculated. The SCFM is applied to quantum systems compounds by neutral and charged (electrons) particles, studying the generalized susceptibility of the system. Thus, properties as the structure factor, pair correlation function, excitation energy spectra, sound velocity, etc are obtained self-consistently (L.C.) [pt

  13. Integrated studies into characteristics of physical fields using discontinuous geomedium models under external loading

    Science.gov (United States)

    Usoltseva Vostrikov, OM, VI; Tsoy, PA; Semenov, VN

    2018-03-01

    The article presents the laboratory study of deformation in artificial layered geomaterial samples down to failure with the simultaneous measurement of stresses, strains, micro-strains and signals of microseismic emission. The analysis of the synchronized experimental data made it possible to determine features of change in the microseismicity parameters and micro-strain fields in the samples depending on the deformation stage, and also to reveal the dynamics of evolution of microfailures and the main fracture zone.

  14. High field magnetisation studies in some rare earth based amorphous ribbons

    Science.gov (United States)

    Krishnan, R.; Lassri, H.; Driouch, L.

    1995-02-01

    We have carried out magnetisation studies at fields up to 20 T of melt spun amorphous Fe 72- xY xHo 8B 20 alloys. The approach to saturation for H ≤ 11 T has been analysed on the basis of Chudnovsky's model, and the exchange constant, random anisotropy etc. have been calculated. We have also extracted the local anisotropy from the coercivity.

  15. A preliminary field study of patient flow management in a trauma center for designing information technology*

    OpenAIRE

    Gurses, Ayse P.; Hu, Peter; Gilger, Sheila; Dutton, Richard P.; Trainum, Therese; Ross, Kathy; Xiao, Yan

    2006-01-01

    We described the information transfer and communication activities of nurse coordinators (NCO), who lead patient flow management in a major trauma center. A field study was conducted to identify information sources and information tools used, leading purposes of communication, and the information types NCOs need for patient flow management. In addition to verbal communication, NCOs frequently used a combination of patient-oriented and process-oriented information tools.

  16. Balancing Control and Complexity in Field Studies of Neonicotinoids and Honey Bee Health

    Directory of Open Access Journals (Sweden)

    Sainath Suryanarayanan

    2013-03-01

    Full Text Available Amidst ongoing declines in honey bee health, the contributory role of the newer systemic insecticides continues to be intensely debated. Scores of toxicological field experiments, which bee scientists and regulators in the United States have looked to for definitive causal evidence, indicate a lack of support. This paper analyzes the methodological norms that shape the design and interpretation of field toxicological studies. I argue that contemporary field studies of honey bees and pesticides are underpinned by a “control-oriented” approach, which precludes a serious investigation of the indirect and multifactorial ways in which pesticides could drive declines in honey bee health. I trace the historical rise to prominence of this approach in honey bee toxicology to the development of entomology as a science of insecticide development in the United States. Drawing on “complexity-oriented” knowledge practices in ecology, epidemiology, beekeeping and sociology, I suggest an alternative socio-ecological systems approach, which would entail in situ studies that are less concerned with isolating individual factors and more attentive to the interactive and place-based mix of factors affecting honey bee health.

  17. The Lathrop Wells volcanic center: Status of field and geochronology studies

    International Nuclear Information System (INIS)

    Crowe, B.; Morley, R.; Wells, S.; Geissman, J.; McDonald, E.; McFadden, L.; Perry, F.; Murrell, M.; Poths, J.; Forman, S.

    1992-01-01

    The purpose of this paper is to describe the status of field and geochronology studies of the Lathrop Wells volcanic center. Our perspective is that it is critical to assess all possible methods for obtaining cross-checking data to resolve chronology and field problems. It is equally important to consider application of the range of chronology methods available in Quaternary geologic research. Such an approach seeks to increase the confidence in data interpretations through obtaining convergence among separate isotopic, radiogenic, and age-correlated methods. Finally, the assumptions, strengths, and weaknesses of each dating method need to be carefully described to facilitate an impartial evaluation of results. The paper is divided into two parts. The first part describes the status of continuing field studies for the volcanic center for this area south of Yucca Mountain, Nevada. The second part presents an overview of the preliminary results of ongoing chronology studies and their constraints on the age and stratigraphy of the Lathrop Wells volcanic center. Along with the chronology data, the assumptions, strengths, and limitations of each methods are discussed

  18. Self-reported symptoms associated with exposure to electromagnetic fields: a questionnaire study.

    Science.gov (United States)

    Küçer, Nermin; Pamukçu, Tuğba

    2014-01-01

    Abstract In the last years, it has been discussed frequently whether there are any harmful effects of electromagnetic fields on human health. Electromagnetic fields are generated by several natural and man-made sources. Part of the electromagnetic spectrum called Radiofrequency is used in communication systems such as mobile (cellular) phone and computer. The aim of our study was to explore different self-reported symptoms that may be associated with exposure to electromagnetic fields. This survey study was conducted, using a questionnaire, on 350 people aged +9 years in Turkey. The chi-square test was used for data analysis. Self-reported symptoms were headache, vertigo/dizziness, fatigue, forgetfulness, sleep disturbance-insomnia, tension-anxiety, joint and bone pain, lacrimation of the eyes, hearing loss and tinnitus. As a result of the survey, the study has shown that users of mobile phone and computer more often complained of headache, joint and bone pain, hearing loss, vertigo/dizziness, tension-anxiety symptoms according to time of daily usage (p < 0.05). In users of mobile phone and computer, women significantly (p < 0.05) complained more often of headache, vertigo/dizziness, fatigue, forgetfulness and tension-anxiety than men.

  19. Balancing Control and Complexity in Field Studies of Neonicotinoids and Honey Bee Health.

    Science.gov (United States)

    Suryanarayanan, Sainath

    2013-03-05

    Amidst ongoing declines in honey bee health, the contributory role of the newer systemic insecticides continues to be intensely debated. Scores of toxicological field experiments, which bee scientists and regulators in the United States have looked to for definitive causal evidence, indicate a lack of support. This paper analyzes the methodological norms that shape the design and interpretation of field toxicological studies. I argue that contemporary field studies of honey bees and pesticides are underpinned by a "control-oriented" approach, which precludes a serious investigation of the indirect and multifactorial ways in which pesticides could drive declines in honey bee health. I trace the historical rise to prominence of this approach in honey bee toxicology to the development of entomology as a science of insecticide development in the United States. Drawing on "complexity-oriented" knowledge practices in ecology, epidemiology, beekeeping and sociology, I suggest an alternative socio-ecological systems approach, which would entail in situ studies that are less concerned with isolating individual factors and more attentive to the interactive and place-based mix of factors affecting honey bee health.

  20. Molecules in strong laser fields. In depth study of H2 molecule

    International Nuclear Information System (INIS)

    Awasthi, Manohar

    2009-01-01

    -threshold-ionization peaks is also demonstrated. The CI-TDSE results for H 2 are used for testing the validity of SAE approximation. In strong field physics, there are models based on the SAE approximation. Most popular are the Ammosov-Delone-Krainov (ADK) model, a molecular version of the ADK model called MO-ADK (MO stands for molecular orbital) and the strong field approximation (SFA). The validity of the second method for the solution of TDSE in SAE approximation is investigated by applying it to H 2 molecule where the exact two-electron results were already calculated using CI-TDSE. The SAE method uses density-functional-theory (DFT) for the description of field-free eigenstates and is thus abbreviated as DFT-SAE-TDSE. Since DFT is used for the calculation of field-free states, different functionals were also tested. The validity of MO-ADK model is also investigated. After establishing the DFT-SAE-TDSE method, the first excited state B 1 Σ u + of H 2 is studied over a large range of laser parameters. The effect of the closely lying excited states on ionization and excitation is studied. After successful testing of DFT-SAE-TDSE method on H 2 molecule, the results for larger molecules like N 2 , O 2 and C 2 H 2 in the DFT-SAE framework are presented. (orig.)