Laser coupling to reduced-scale targets at Nif Early Light

Energy Technology Data Exchange (ETDEWEB)

Hinkel, D.E.; Schneider, M.B.; Young, B.K.; Holder, J.P.; Langdon, A.B.; Bonanno, G.; Bower, D.E.; Bruns, H.C.; Campbell, K.M.; Celeste, J.R.; Compton, S.; Costa, R.L.; Dewald, E.L.; Dixit, S.N.; Eckart, M.J.; Eder, D.C.; Edwards, M.J.; Ellis, A.D.; Emig, J.A.; Froula, D.H.; Glenzer, S.H.; Hargrove, D.; Haynam, C.A.; Heeter, R.F.; Henesian, M.A.; Holtmeier, G.; James, D.L.; Jancaitis, K.S.; Kalantar, K.H.; Kamperschroer, J.H.; Kauffman, R.L.; Kimbrough, J.; Kirkwood, R.K.; Koniges, A.E.; Landen, O.L.; Landon, M.; Lee, F.D.; MacGowan, B.J.; Mackinnon, A.J.; Manes, K.R.; Marshall, C.; May, M.J.; McDonald, J.W.; Menapace, J.; Moses, S.E.I.; Munro, D.H.; Murray, J.R.; Niemann, C.; Power, G.D.; Rekow, V.; Ruppe, J.A.; Schein, J.; Shepherd, R.; Singh, M.S.; Springer, P.T.; Still, C.H.; Suter, L.J.; Tietbohl, G.L.; Turner, R.E.; VanWonterghem, B.M.; Wallace, R.J.; Warrick, A.; Weber, F.; Wegner, P.J.; Williams, E.A.; Young, P.E. [Lawrence Livermore National Laboratory, Livermore, CA (United States); Baldis, H.A. [California at Davis Univ., CA (United States); Pellinen, D.; Watts, P. [Bechtel Nevada Corporation, Livermore, CA (United States)

2006-06-15

Deposition of maximum laser energy into a small, high-Z enclosure in a short laser pulse creates a hot environment. Such targets were recently included in an experimental campaign using the first four of the 192 beams of the National Ignition Facility (NIF) under construction at the University of California Lawrence Livermore National Laboratory. These targets demonstrate good laser coupling, reaching a radiation temperature of 340 eV. In addition, the Raman backscatter spectrum contains features consistent with Brillouin backscatter of Raman forward scatter. Also, NIF Early Light diagnostics indicate that 20% of the direct backscatter from these reduced-scale targets is in the polarization orthogonal to that of the incident light. (authors)

Geminal-spanning orbitals make explicitly correlated reduced-scaling coupled-cluster methods robust, yet simple

Science.gov (United States)

Pavošević, Fabijan; Neese, Frank; Valeev, Edward F.

2014-08-01

We present a production implementation of reduced-scaling explicitly correlated (F12) coupled-cluster singles and doubles (CCSD) method based on pair-natural orbitals (PNOs). A key feature is the reformulation of the explicitly correlated terms using geminal-spanning orbitals that greatly reduce the truncation errors of the F12 contribution. For the standard S66 benchmark of weak intermolecular interactions, the cc-pVDZ-F12 PNO CCSD F12 interaction energies reproduce the complete basis set CCSD limit with mean absolute error cost compared to the conventional CCSD F12.

Fatigue of 1 {mu}m-scale gold by vibration with reduced resonant frequency

Energy Technology Data Exchange (ETDEWEB)

Sumigawa, Takashi, E-mail: sumigawa@cyber.kues.kyoto-u.ac.jp [Department of Mechanical Engineering and Science, Kyoto University, Yoshidahommachi, Sakyo-ku, Kyoto 606-8501 (Japan); Matsumoto, Kenta [Department of Mechanical Engineering and Science, Kyoto University, Yoshidahommachi, Sakyo-ku, Kyoto 606-8501 (Japan); Tsuchiya, Toshiyuki [Department of Micro Engineering, Kyoto University, Yoshidahommachi, Sakyo-ku, Kyoto 606-8501 (Japan); Kitamura, Takayuki [Department of Mechanical Engineering and Science, Kyoto University, Yoshidahommachi, Sakyo-ku, Kyoto 606-8501 (Japan)

2012-10-30

In order to investigate the fatigue strength of micro-metal (1 {mu}m-scale), a testing method using resonant vibration is developed. Although the loading by vibration can solve the difficulties associated with the fatigue experiment of micro-specimen (e.g., specimen gripping and high-cycle loading under tension-compression), it inherently has an excessively high resonance frequency (more than several GHz at least) in a 1 {mu}m-scale metal specimen. For control of the fatigue cycle, the resonance frequency must be reduced to several hundreds of kHz by tuning the specimen shape. We design a cantilever specimen of 1 {mu}m scale gold with a weight at the tip, which reduces the resonant frequency to about 330 kHz. The unique specimen with the test section of 1.26 {mu}m Multiplication-Sign 0.94 {mu}m Multiplication-Sign 1.52 {mu}m is successfully fabricated by a novel technique using a focused ion beam and the tension-compression fatigue cycle is applied to it by means of a piezoelectric actuator. The test section breaks at about 1.6 Multiplication-Sign 10{sup 6} cycles under {Delta}{sigma}/2=230 MPa, which is within the targeted range of this project. It is easy to extend this method to high-cycle fatigue for actual use (including the failure cycles of over 10{sup 8} cycles). The slip bands observed on the surface, which have concavity and convexity similar to the intrusions/extrusions of PSBs, indicate that the failure is induced by the fatigue.

Energy conservation in reheating furnaces by reducing scrap and scale formation; Kuumamuokkauksen energiasaeaestoet romun maeaeraeae ja hilseilyae vaehentaemaellae

Energy Technology Data Exchange (ETDEWEB)

Kivivuori, S.; Savolainen, P.; Fredriksson, J.; Paavola, J. [Helsinki Univ. of Technology, Otaniemi (Finland). Lab. of Materials Processing and Powder Metallurgy

1996-12-31

The main objective of the project `Energy Savings in Reheating Furnaces by Reducing Scrap and Scale Formation` is to reduce energy consumption and environmental harms in reheating and rolling of steel. This was done by analysing the different atmospheres in reheating furnaces of the steel companies participating in this project. These atmospheres were then simulated in a laboratory furnace. Scale formation tests with different steel grades were then carried out in these atmospheres. Scale removal tests were done to some steel grades too. The results showed that lower oxygen content - as expected - decreases oxidation despite the even higher carbondioxide content in the atmosphere. Lower oxygen content may cause difficulties in scale removal. This however is highly dependent on the steel grade. Heat treatment tests showed the effect of increased temperature and furnace time on decarburization. Some energy savings was obtained in fuel consumption by optimising the operation parameters and the atmosphere steadier in different reheating furnaces. (orig.)

Energy conservation in reheating furnaces by reducing scrap and scale formation; Kuumamuokkauksen energiasaeaestoet romun maeaeraeae ja hilseilyae vaehentaemaellae

Energy Technology Data Exchange (ETDEWEB)

Kivivuori, S; Savolainen, P; Fredriksson, J; Paavola, J [Helsinki Univ. of Technology, Otaniemi (Finland). Lab. of Materials Processing and Powder Metallurgy

1997-12-31

The main objective of the project `Energy Savings in Reheating Furnaces by Reducing Scrap and Scale Formation` is to reduce energy consumption and environmental harms in reheating and rolling of steel. This was done by analysing the different atmospheres in reheating furnaces of the steel companies participating in this project. These atmospheres were then simulated in a laboratory furnace. Scale formation tests with different steel grades were then carried out in these atmospheres. Scale removal tests were done to some steel grades too. The results showed that lower oxygen content - as expected - decreases oxidation despite the even higher carbondioxide content in the atmosphere. Lower oxygen content may cause difficulties in scale removal. This however is highly dependent on the steel grade. Heat treatment tests showed the effect of increased temperature and furnace time on decarburization. Some energy savings was obtained in fuel consumption by optimising the operation parameters and the atmosphere steadier in different reheating furnaces. (orig.)

Numerical Study on Similarity of Plume’s Infrared Radiation from Reduced Scaling Solid Rocket

Directory of Open Access Journals (Sweden)

Xiaoying Zhang

2015-01-01

Full Text Available Similarity of plume radiation between reduced scaling solid rocket models and full scale ones in ground conditions has been taken for investigation. Flow and radiation of plume from solid rockets with scaling ratio from 0.1 to 1 have been computed. The radiative transfer equation (RTE is solved by the finite volume method (FVM in infrared band 2~6 μm. The spectral characteristics of plume gases have been calculated with the weighted-sum-of-gray-gas (WSGG model, and those of the Al2O3 particles have been solved by the Mie scattering model. Our research shows that, with the decreasing scaling ratio of the rocket engine, the radiation intensity of the plume decreases with 1.5~2.5 power of the scaling ratio. The infrared radiation of the plume gases shows a strong spectral dependency, while that of the Al2O3 particles shows grey property. Spectral radiation intensity of the high temperature core of the solid rocket plume increases greatly in the peak absorption spectrum of plume gases. Al2O3 particle is the major radiation composition in the rocket plume, whose scattering coefficient is much larger than its absorption coefficient. There is good similarity between spectral variations of plumes from different scaling solid rockets. The directional plume radiation rises with the increasing azimuth angle.

Seismic tests on a reduced scale mock-up of a reprocessing plant cooling pond

International Nuclear Information System (INIS)

Queval, J.C.; Gantenbein, F.; Lebelle, M.

1995-01-01

In conjunction with COGEMA and SGN, CEA has launched an important research program to validate the reprocessing plant cooling pond calculation mainly for the effect of the racks on the fluid-pond interaction. The paper presents the tests performed on a reduced scale mock-up (scale 1/5). The tests are composed by: -random excitations at very low excitation level to measure the natural frequencies, especially the first sloshing mode frequency; -sinusoidal tests to measure the damping; -seismic tests performed with 3 different time reduction scales (1, 1/5, 1/√5) and 3 different synthetic accelerograms. Two types of simplified model with added masses and finite element model were developed. Comparisons of measured and calculated pressure fields against the panels will be presented. The measured frequencies, obtained during tests, are in good agreement with Housner's results. (authors). 2 refs., 4 figs., 5 tabs

High-resolution LES of the rotating stall in a reduced scale model pump-turbine

International Nuclear Information System (INIS)

Pacot, Olivier; Avellan, François; Kato, Chisachi

2014-01-01

Extending the operating range of modern pump-turbines becomes increasingly important in the course of the integration of renewable energy sources in the existing power grid. However, at partial load condition in pumping mode, the occurrence of rotating stall is critical to the operational safety of the machine and on the grid stability. The understanding of the mechanisms behind this flow phenomenon yet remains vague and incomplete. Past numerical simulations using a RANS approach often led to inconclusive results concerning the physical background. For the first time, the rotating stall is investigated by performing a large scale LES calculation on the HYDRODYNA pump-turbine scale model featuring approximately 100 million elements. The computations were performed on the PRIMEHPC FX10 of the University of Tokyo using the overset Finite Element open source code FrontFlow/blue with the dynamic Smagorinsky turbulence model and the no-slip wall condition. The internal flow computed is the one when operating the pump-turbine at 76% of the best efficiency point in pumping mode, as previous experimental research showed the presence of four rotating cells. The rotating stall phenomenon is accurately reproduced for a reduced Reynolds number using the LES approach with acceptable computing resources. The results show an excellent agreement with available experimental data from the reduced scale model testing at the EPFL Laboratory for Hydraulic Machines. The number of stall cells as well as the propagation speed corroborates the experiment

High-resolution LES of the rotating stall in a reduced scale model pump-turbine

Science.gov (United States)

Pacot, Olivier; Kato, Chisachi; Avellan, François

2014-03-01

Extending the operating range of modern pump-turbines becomes increasingly important in the course of the integration of renewable energy sources in the existing power grid. However, at partial load condition in pumping mode, the occurrence of rotating stall is critical to the operational safety of the machine and on the grid stability. The understanding of the mechanisms behind this flow phenomenon yet remains vague and incomplete. Past numerical simulations using a RANS approach often led to inconclusive results concerning the physical background. For the first time, the rotating stall is investigated by performing a large scale LES calculation on the HYDRODYNA pump-turbine scale model featuring approximately 100 million elements. The computations were performed on the PRIMEHPC FX10 of the University of Tokyo using the overset Finite Element open source code FrontFlow/blue with the dynamic Smagorinsky turbulence model and the no-slip wall condition. The internal flow computed is the one when operating the pump-turbine at 76% of the best efficiency point in pumping mode, as previous experimental research showed the presence of four rotating cells. The rotating stall phenomenon is accurately reproduced for a reduced Reynolds number using the LES approach with acceptable computing resources. The results show an excellent agreement with available experimental data from the reduced scale model testing at the EPFL Laboratory for Hydraulic Machines. The number of stall cells as well as the propagation speed corroborates the experiment.

Extreme robustness of scaling in sample space reducing processes explains Zipf’s law in diffusion on directed networks

International Nuclear Information System (INIS)

Corominas-Murtra, Bernat; Hanel, Rudolf; Thurner, Stefan

2016-01-01

It has been shown recently that a specific class of path-dependent stochastic processes, which reduce their sample space as they unfold, lead to exact scaling laws in frequency and rank distributions. Such sample space reducing processes offer an alternative new mechanism to understand the emergence of scaling in countless processes. The corresponding power law exponents were shown to be related to noise levels in the process. Here we show that the emergence of scaling is not limited to the simplest SSRPs, but holds for a huge domain of stochastic processes that are characterised by non-uniform prior distributions. We demonstrate mathematically that in the absence of noise the scaling exponents converge to −1 (Zipf’s law) for almost all prior distributions. As a consequence it becomes possible to fully understand targeted diffusion on weighted directed networks and its associated scaling laws in node visit distributions. The presence of cycles can be properly interpreted as playing the same role as noise in SSRPs and, accordingly, determine the scaling exponents. The result that Zipf’s law emerges as a generic feature of diffusion on networks, regardless of its details, and that the exponent of visiting times is related to the amount of cycles in a network could be relevant for a series of applications in traffic-, transport- and supply chain management. (paper)

Laser coupling to reduced-scale targets at NIF Early Light

International Nuclear Information System (INIS)

Hinkel, D E; Schneider, M B; Young, B K; Holder, J P; Langdon, A B; Baldis, H A; Bonanno, G; Bower, D E; Bruns, H C; Campbell, K M; Celeste, J R; Compton, S; Costa, R L; Dewald, E L; Dixit, S N; Eckart, M J; Eder, D C; Edwards, M J; Ellis, A D; Emig, J A; Froula, D H; Glenzer, S H; Hargrove, D; Haynam, C A; Heeter, R F; Henesian, M A; Holtmeier, G; James, D L; Jancaitis, K S; Kalantar, D H; Kamperschroer, J H; Kauffman, R L; Kimbrough, J; Kirkwood, R K; Koniges, A E; Landen, O L; Landon, M; Lee, F D; MacGowan, B J; Mackinnon, A J; Manes, K R; Marshall, C; May, M J; McDonald, J W; Menapace, J; Moses, S I; Munro, D H; Murray, J R; Niemann, C; Pellinen, D; Power, G D; Rekow, V; Ruppe, J A; Schein, J; Shepherd, R; Singh, M S; Springer, P; Still, C H; Suter, L J; Tietbohl, G L; Turner, R E; VanWonterghem, B M; Wallace, R J; Warrick, A; Watts, P; Weber, F; Wegner, P J; Williams, E A; Young, P E

2005-01-01

Deposition of maximum laser energy into a small, high-Z enclosure in a short laser pulse creates a hot environment. Such targets were recently included in an experimental campaign using the first four of the 192 beams of the National Ignition Facility [J. A. Paisner, E. M. Campbell, and W. J. Hogan, Fusion Technology 26 26, 755 (1994)], under construction at the University of California Lawrence Livermore National Laboratory. These targets demonstrate good laser coupling, reaching a radiation temperature of 340 eV. In addition, the Raman backscatter spectrum contains features consistent with Brillouin backscatter of Raman forward scatter [A. B. Langdon and D. E. Hinkel, Physical Review Letters 89, 015003 (2002)]. Also, NIF Early Light diagnostics indicate that 20% of the direct backscatter from these reduced-scale targets is in the polarization orthogonal to that of the incident light

Reduced-scale experimental investigation on ventilation performance of a local exhaust hood in an industrial plant

DEFF Research Database (Denmark)

Huang, Yanqiu; Wang, Yi; Liu, Li

2015-01-01

stratification in the working areas of industrial plants. Investigated factors were confined airflow boundaries, flow rates of the exhaust hoods, source strengths, airflow obstacles and distances between sources and exhaust hoods. Reduced-scale experiments were conducted with a geometric scale of 1...... efficiency. Hood performance was also evaluated by thermal stratification heights in the plants. This study could help improve the capture efficiency of local ventilation systems used in industrial plants. Safe operation heights are recommended in the upper space of industrial plants based on the thermal...

What scaling means in wind engineering: Complementary role of the reduced scale approach in a BLWT and the full scale testing in a large climatic wind tunnel

Science.gov (United States)

Flamand, Olivier

2017-12-01

Wind engineering problems are commonly studied by wind tunnel experiments at a reduced scale. This introduces several limitations and calls for a careful planning of the tests and the interpretation of the experimental results. The talk first revisits the similitude laws and discusses how they are actually applied in wind engineering. It will also remind readers why different scaling laws govern in different wind engineering problems. Secondly, the paper focuses on the ways to simplify a detailed structure (bridge, building, platform) when fabricating the downscaled models for the tests. This will be illustrated by several examples from recent engineering projects. Finally, under the most severe weather conditions, manmade structures and equipment should remain operational. What “recreating the climate” means and aims to achieve will be illustrated through common practice in climatic wind tunnel modelling.

Testing the effectiveness of certainty scales, cheap talk, and dissonance-minimization in reducing hypothetical bias in contingent valuation studies

Science.gov (United States)

Mark Morrison; Thomas C. Brown

2009-01-01

Stated preference methods such as contingent valuation and choice modeling are subject to various biases that may lead to differences between actual and hypothetical willingness to pay. Cheap talk, follow-up certainty scales, and dissonance minimization are three techniques for reducing this hypothetical bias. Cheap talk and certainty scales have received considerable...

Reduced Fracture Finite Element Model Analysis of an Efficient Two-Scale Hybrid Embedded Fracture Model

KAUST Repository

Amir, Sahar Z.

2017-06-09

A Hybrid Embedded Fracture (HEF) model was developed to reduce various computational costs while maintaining physical accuracy (Amir and Sun, 2016). HEF splits the computations into fine scale and coarse scale. Fine scale solves analytically for the matrix-fracture flux exchange parameter. Coarse scale solves for the properties of the entire system. In literature, fractures were assumed to be either vertical or horizontal for simplification (Warren and Root, 1963). Matrix-fracture flux exchange parameter was given few equations built on that assumption (Kazemi, 1968; Lemonnier and Bourbiaux, 2010). However, such simplified cases do not apply directly for actual random fracture shapes, directions, orientations …etc. This paper shows that the HEF fine scale analytic solution (Amir and Sun, 2016) generates the flux exchange parameter found in literature for vertical and horizontal fracture cases. For other fracture cases, the flux exchange parameter changes according to the angle, slop, direction, … etc. This conclusion rises from the analysis of both: the Discrete Fracture Network (DFN) and the HEF schemes. The behavior of both schemes is analyzed with exactly similar fracture conditions and the results are shown and discussed. Then, a generalization is illustrated for any slightly compressible single-phase fluid within fractured porous media and its results are discussed.

Reduced Fracture Finite Element Model Analysis of an Efficient Two-Scale Hybrid Embedded Fracture Model

KAUST Repository

Amir, Sahar Z.; Chen, Huangxin; Sun, Shuyu

2017-01-01

A Hybrid Embedded Fracture (HEF) model was developed to reduce various computational costs while maintaining physical accuracy (Amir and Sun, 2016). HEF splits the computations into fine scale and coarse scale. Fine scale solves analytically for the matrix-fracture flux exchange parameter. Coarse scale solves for the properties of the entire system. In literature, fractures were assumed to be either vertical or horizontal for simplification (Warren and Root, 1963). Matrix-fracture flux exchange parameter was given few equations built on that assumption (Kazemi, 1968; Lemonnier and Bourbiaux, 2010). However, such simplified cases do not apply directly for actual random fracture shapes, directions, orientations …etc. This paper shows that the HEF fine scale analytic solution (Amir and Sun, 2016) generates the flux exchange parameter found in literature for vertical and horizontal fracture cases. For other fracture cases, the flux exchange parameter changes according to the angle, slop, direction, … etc. This conclusion rises from the analysis of both: the Discrete Fracture Network (DFN) and the HEF schemes. The behavior of both schemes is analyzed with exactly similar fracture conditions and the results are shown and discussed. Then, a generalization is illustrated for any slightly compressible single-phase fluid within fractured porous media and its results are discussed.

Large-Scale Ocean Circulation-Cloud Interactions Reduce the Pace of Transient Climate Change

Science.gov (United States)

Trossman, D. S.; Palter, J. B.; Merlis, T. M.; Huang, Y.; Xia, Y.

2016-01-01

Changes to the large scale oceanic circulation are thought to slow the pace of transient climate change due, in part, to their influence on radiative feedbacks. Here we evaluate the interactions between CO2-forced perturbations to the large-scale ocean circulation and the radiative cloud feedback in a climate model. Both the change of the ocean circulation and the radiative cloud feedback strongly influence the magnitude and spatial pattern of surface and ocean warming. Changes in the ocean circulation reduce the amount of transient global warming caused by the radiative cloud feedback by helping to maintain low cloud coverage in the face of global warming. The radiative cloud feedback is key in affecting atmospheric meridional heat transport changes and is the dominant radiative feedback mechanism that responds to ocean circulation change. Uncertainty in the simulated ocean circulation changes due to CO2 forcing may contribute a large share of the spread in the radiative cloud feedback among climate models.

Reduced Voltage Scaling in Clock Distribution Networks

Directory of Open Access Journals (Sweden)

Khader Mohammad

2009-01-01

Full Text Available We propose a novel circuit technique to generate a reduced voltage swing (RVS signals for active power reduction on main buses and clocks. This is achieved without performance degradation, without extra power supply requirement, and with minimum area overhead. The technique stops the discharge path on the net that is swinging low at a certain voltage value. It reduces active power on the target net by as much as 33% compared to traditional full swing signaling. The logic 0 voltage value is programmable through control bits. If desired, the reduced-swing mode can also be disabled. The approach assumes that the logic 0 voltage value is always less than the threshold voltage of the nMOS receivers, which eliminate the need of the low to high voltage translation. The reduced noise margin and the increased leakage on the receiver transistors using this approach have been addressed through the selective usage of multithreshold voltage (MTV devices and the programmability of the low voltage value.

Reducing Agricultural Water Footprints at the Farm Scale: A Case Study in the Beijing Region

Directory of Open Access Journals (Sweden)

Jing Huang

2015-12-01

Full Text Available Beijing is one of the most water-stressed regions in the world. Reducing agricultural water use has long been the basis of local policy for sustainable water use. In this article, the potential to reduce the life cycle (cradle to gate water footprints of wheat and maize that contribute to 94% of the local cereal production was assessed. Following ISO 14046, consumptive and degradative water use for the wheat-maize rotation system was modeled under different irrigation and nitrogen (N application options. Reducing irrigation water volume by 33.3% compared to current practice did not cause a significant yield decline, but the water scarcity footprint and water eutrophication footprint were decreased by 27.5% and 23.9%, respectively. Similarly, reducing the N application rate by 33.3% from current practice did not cause a significant yield decline, but led to a 52.3% reduction in water eutrophication footprint while maintaining a similar water scarcity footprint. These results demonstrate that improving water and fertilizer management has great potential for reducing the crop water footprints at the farm scale. This situation in Beijing is likely to be representative of the challenge facing many of the water-stressed regions in China, where a sustainable means of agricultural production must be found.

Communication: A reduced scaling J-engine based reformulation of SOS-MP2 using graphics processing units

Energy Technology Data Exchange (ETDEWEB)

Maurer, S. A.; Kussmann, J.; Ochsenfeld, C., E-mail: Christian.Ochsenfeld@cup.uni-muenchen.de [Chair of Theoretical Chemistry, Department of Chemistry, University of Munich (LMU), Butenandtstr. 7, D-81377 München (Germany); Center for Integrated Protein Science (CIPSM) at the Department of Chemistry, University of Munich (LMU), Butenandtstr. 5–13, D-81377 München (Germany)

2014-08-07

We present a low-prefactor, cubically scaling scaled-opposite-spin second-order Møller-Plesset perturbation theory (SOS-MP2) method which is highly suitable for massively parallel architectures like graphics processing units (GPU). The scaling is reduced from O(N{sup 5}) to O(N{sup 3}) by a reformulation of the MP2-expression in the atomic orbital basis via Laplace transformation and the resolution-of-the-identity (RI) approximation of the integrals in combination with efficient sparse algebra for the 3-center integral transformation. In contrast to previous works that employ GPUs for post Hartree-Fock calculations, we do not simply employ GPU-based linear algebra libraries to accelerate the conventional algorithm. Instead, our reformulation allows to replace the rate-determining contraction step with a modified J-engine algorithm, that has been proven to be highly efficient on GPUs. Thus, our SOS-MP2 scheme enables us to treat large molecular systems in an accurate and efficient manner on a single GPU-server.

Communication: A reduced scaling J-engine based reformulation of SOS-MP2 using graphics processing units.

Science.gov (United States)

Maurer, S A; Kussmann, J; Ochsenfeld, C

2014-08-07

We present a low-prefactor, cubically scaling scaled-opposite-spin second-order Møller-Plesset perturbation theory (SOS-MP2) method which is highly suitable for massively parallel architectures like graphics processing units (GPU). The scaling is reduced from O(N⁵) to O(N³) by a reformulation of the MP2-expression in the atomic orbital basis via Laplace transformation and the resolution-of-the-identity (RI) approximation of the integrals in combination with efficient sparse algebra for the 3-center integral transformation. In contrast to previous works that employ GPUs for post Hartree-Fock calculations, we do not simply employ GPU-based linear algebra libraries to accelerate the conventional algorithm. Instead, our reformulation allows to replace the rate-determining contraction step with a modified J-engine algorithm, that has been proven to be highly efficient on GPUs. Thus, our SOS-MP2 scheme enables us to treat large molecular systems in an accurate and efficient manner on a single GPU-server.

Preliminary Study on a Reduced Scaled Model Regarding the Air Diffusion inside a Crew Quarter on Board of the ISS

Science.gov (United States)

Sandu, Mihnea; Nastase, Ilinca; Bode, Florin; Croitoru, CristianaVerona; Tacutu, Laurentiu

2018-02-01

The paper focus on the air quality inside the Crew Quarters on board of the International Space Station. Several issues to improve were recorded by NASA and ESA and most important of them are the following: noise level reduction, CO2 accumulation reduction and dust accumulation reduction. The study in this paper is centred on a reduced scaled model used to provide simulations related to the air diffusion inside the CQ. It is obvious that a new ventilation system is required to achieve the three issues mentioned above, and the solutions obtained by means of numerical simulation need to be validated by experimental approach. First of all we have built a reduced scaled physical model to simulate the flow pattern inside the CQ and the equipment inside the CQ has been reproduced using a geometrical scale ratio. The flow pattern was considered isothermal and incompressible. The similarity criteria used was the Reynolds number to characterize the flow pattern and the length scale was set at value 1/4. Water has been used inside the model to simulate air. Velocity magnitude vectors have been obtained using PIV measurement techniques.

Preliminary Study on a Reduced Scaled Model Regarding the Air Diffusion inside a Crew Quarter on Board of the ISS

Directory of Open Access Journals (Sweden)

Sandu Mihnea

2018-01-01

Full Text Available The paper focus on the air quality inside the Crew Quarters on board of the International Space Station. Several issues to improve were recorded by NASA and ESA and most important of them are the following: noise level reduction, CO2 accumulation reduction and dust accumulation reduction. The study in this paper is centred on a reduced scaled model used to provide simulations related to the air diffusion inside the CQ. It is obvious that a new ventilation system is required to achieve the three issues mentioned above, and the solutions obtained by means of numerical simulation need to be validated by experimental approach. First of all we have built a reduced scaled physical model to simulate the flow pattern inside the CQ and the equipment inside the CQ has been reproduced using a geometrical scale ratio. The flow pattern was considered isothermal and incompressible. The similarity criteria used was the Reynolds number to characterize the flow pattern and the length scale was set at value 1/4. Water has been used inside the model to simulate air. Velocity magnitude vectors have been obtained using PIV measurement techniques.

Pilot scale ion exchange column study for reducing radioactivity discharges to environment

International Nuclear Information System (INIS)

Kore, S.G.; Yadav, V.K.; Sonar, N.L.; Valsala, T.P.; Narayan, J.; Sharma, S.P.; Chattopadhyay, S.; Dani, U.; Vishwaraj, I.

2013-01-01

Low level liquid waste (LLW) is generated during operation of Tarapur Atomic Power Station (TAPS). Chemical co-precipitation is the treatment method used for decontamination of this waste with respect to radionuclide prior to discharge to environment. Further polishing of effluent from the treated LLW was planned using ion exchange column to reduce the discharges to the environment In view of this ion exchange column study was carried out in the laboratory using in-house prepared cobalt ferrocyanide (COFC) based composite resin. Based on the encouraging results obtained in the lab studies, pilot scale study was carried out in the plant. Decontamination factor (DF) of 14-15 was obtained with respect to Cs isotopes and overall DF of 2-5 was obtained with respect to gross beta activity. (author)

Biofunctionality and immunocompatibility of starch-based biomaterials

Science.gov (United States)

Marques, Alexandra Margarida Pinto

A procura de novos biomateriais que desempenhem funcoes especificas sem, no entanto, desencadearem respostas negativas nos hospedeiros constitui um desafio permanente e actual nesta area. Biomateriais degradaveis foram uma das solucoes propostas e actualmente em aplicacao mas, embora possuam vantagens inegaveis, tambem apresentam alguns problemas nomeadamente no que diz respeito aos seus produtos de degradacao e respectivos efeitos negativos consequentes. Outros biomateriais, entre os quais polimeros de origem natural, foram propostos considerando que os seus produtos de degradacao poderao ser incorporados nas vias metabolicas normais evitando efeitos secundarios no hospedeiro. Ate ao momento, e apesar de todos os esforcos e do grande numero de dispositivos biomedicos desenvolvidos, o biomaterial ideal para uma aplicacao especifica ainda nao foi encontrado. Estudos com polimeros biodegradaveis a base de amido demonstraram que estes materiais possuem propriedades promissoras abrindo novas perspectivas para a sua possivel aplicacao numa variedade de aplicacoes biomedicas. Assim, de modo a demonstrar que estes materiais tem de facto potencial para serem utilizados em, por exemplo, substituicao ossea, sistemas de libertacao controlada, cimentos osseos e engenharia de tecidos, seria imperativo avaliar com maior profundidade a resposta biologica desencadeada pelos mesmos. Para tal foi delineado um plano de trabalhos com tres objectivos principais: i) avaliar a citocompatibilidade dos polimeros e compositos a base de amido com monitorizacao da citotoxicidade e analise da adesao e proliferacao celulares nas suas superficies. Foi dada particular atencao a osteoblastos considerando uma possivel aplicacao ortopedica para estes materiais; ii) estabelecer modelos in vitro para analisar e prever, tanto quanto possivel, uma situacao real de resposta inflamatoria; iii) validar os resultados in vitro com um modelo in vivo ja estabelecido em outros trabalhos de analise da resposta

Invasive lionfish reduce native fish abundance on a regional scale

Science.gov (United States)

Ballew, Nicholas G.; Bacheler, Nathan M.; Kellison, G. Todd; Schueller, Amy M.

2016-08-01

Invasive lionfish pose an unprecedented threat to biodiversity and fisheries throughout Atlantic waters off of the southeastern United States, the Caribbean, and the Gulf of Mexico. Here, we employ a spatially replicated Before-After-Control-Impact analysis with temporal pairing to quantify for the first time the impact of the lionfish invasion on native fish abundance across a broad regional scale and over the entire duration of the lionfish invasion (1990-2014). Our results suggest that 1) lionfish-impacted areas off of the southeastern United States are most prevalent off-shore near the continental shelf-break but are also common near-shore and 2) in impacted areas, lionfish have reduced tomtate (a native forage fish) abundance by 45% since the invasion began. Tomtate served as a model native fish species in our analysis, and as such, it is likely that the lionfish invasion has had similar impacts on other species, some of which may be of economic importance. Barring the development of a control strategy that reverses the lionfish invasion, the abundance of lionfish in the Atlantic, Caribbean, and Gulf of Mexico will likely remain at or above current levels. Consequently, the effect of lionfish on native fish abundance will likely continue for the foreseeable future.

The tensor hypercontracted parametric reduced density matrix algorithm: coupled-cluster accuracy with O(r(4)) scaling.

Science.gov (United States)

Shenvi, Neil; van Aggelen, Helen; Yang, Yang; Yang, Weitao; Schwerdtfeger, Christine; Mazziotti, David

2013-08-07

Tensor hypercontraction is a method that allows the representation of a high-rank tensor as a product of lower-rank tensors. In this paper, we show how tensor hypercontraction can be applied to both the electron repulsion integral tensor and the two-particle excitation amplitudes used in the parametric 2-electron reduced density matrix (p2RDM) algorithm. Because only O(r) auxiliary functions are needed in both of these approximations, our overall algorithm can be shown to scale as O(r(4)), where r is the number of single-particle basis functions. We apply our algorithm to several small molecules, hydrogen chains, and alkanes to demonstrate its low formal scaling and practical utility. Provided we use enough auxiliary functions, we obtain accuracy similar to that of the standard p2RDM algorithm, somewhere between that of CCSD and CCSD(T).

Reducing diarrhoea deaths in South Africa: costs and effects of scaling up essential interventions to prevent and treat diarrhoea in under-five children.

Science.gov (United States)

Chola, Lumbwe; Michalow, Julia; Tugendhaft, Aviva; Hofman, Karen

2015-04-17

Diarrhoea is one of the leading causes of morbidity and mortality in South African children, accounting for approximately 20% of under-five deaths. Though progress has been made in scaling up multiple interventions to reduce diarrhoea in the last decade, challenges still remain. In this paper, we model the cost and impact of scaling up 13 interventions to prevent and treat childhood diarrhoea in South Africa. Modelling was done using the Lives Saved Tool (LiST). Using 2014 as the baseline, intervention coverage was increased from 2015 until 2030. Three scale up scenarios were compared: by 2030, 1) coverage of all interventions increased by ten percentage points; 2) intervention coverage increased by 20 percentage points; 3) and intervention coverage increased to 99%. The model estimates 13 million diarrhoea cases at baseline. Scaling up intervention coverage averted between 3 million and 5.3 million diarrhoea cases. In 2030, diarrhoeal deaths are expected to reduce from an estimated 5,500 in 2014 to 2,800 in scenario one, 1,400 in scenario two and 100 in scenario three. The additional cost of implementing all 13 interventions will range from US$510 million (US$9 per capita) to US$960 million (US$18 per capita), of which the health system costs range between US$40 million (less than US$1 per capita) and US$170 million (US$3 per capita). Scaling up 13 essential interventions could have a substantial impact on reducing diarrhoeal deaths in South African children, which would contribute toward reducing child mortality in the post-MDG era. Preventive measures are key and the government should focus on improving water, sanitation and hygiene. The investments required to achieve these results seem feasible considering current health expenditure.

Sparse maps—A systematic infrastructure for reduced-scaling electronic structure methods. II. Linear scaling domain based pair natural orbital coupled cluster theory

International Nuclear Information System (INIS)

Riplinger, Christoph; Pinski, Peter; Becker, Ute; Neese, Frank; Valeev, Edward F.

2016-01-01

Domain based local pair natural orbital coupled cluster theory with single-, double-, and perturbative triple excitations (DLPNO-CCSD(T)) is a highly efficient local correlation method. It is known to be accurate and robust and can be used in a black box fashion in order to obtain coupled cluster quality total energies for large molecules with several hundred atoms. While previous implementations showed near linear scaling up to a few hundred atoms, several nonlinear scaling steps limited the applicability of the method for very large systems. In this work, these limitations are overcome and a linear scaling DLPNO-CCSD(T) method for closed shell systems is reported. The new implementation is based on the concept of sparse maps that was introduced in Part I of this series [P. Pinski, C. Riplinger, E. F. Valeev, and F. Neese, J. Chem. Phys. 143, 034108 (2015)]. Using the sparse map infrastructure, all essential computational steps (integral transformation and storage, initial guess, pair natural orbital construction, amplitude iterations, triples correction) are achieved in a linear scaling fashion. In addition, a number of additional algorithmic improvements are reported that lead to significant speedups of the method. The new, linear-scaling DLPNO-CCSD(T) implementation typically is 7 times faster than the previous implementation and consumes 4 times less disk space for large three-dimensional systems. For linear systems, the performance gains and memory savings are substantially larger. Calculations with more than 20 000 basis functions and 1000 atoms are reported in this work. In all cases, the time required for the coupled cluster step is comparable to or lower than for the preceding Hartree-Fock calculation, even if this is carried out with the efficient resolution-of-the-identity and chain-of-spheres approximations. The new implementation even reduces the error in absolute correlation energies by about a factor of two, compared to the already accurate

Prediction of a Francis turbine prototype full load instability from investigations on the reduced scale model

Science.gov (United States)

Alligné, S.; Maruzewski, P.; Dinh, T.; Wang, B.; Fedorov, A.; Iosfin, J.; Avellan, F.

2010-08-01

The growing development of renewable energies combined with the process of privatization, lead to a change of economical energy market strategies. Instantaneous pricings of electricity as a function of demand or predictions, induces profitable peak productions which are mainly covered by hydroelectric power plants. Therefore, operators harness more hydroelectric facilities at full load operating conditions. However, the Francis Turbine features an axi-symmetric rope leaving the runner which may act under certain conditions as an internal energy source leading to instability. Undesired power and pressure fluctuations are induced which may limit the maximum available power output. BC Hydro experiences such constraints in a hydroelectric power plant consisting of four 435 MW Francis Turbine generating units, which is located in Canada's province of British Columbia. Under specific full load operating conditions, one unit experiences power and pressure fluctuations at 0.46 Hz. The aim of the paper is to present a methodology allowing prediction of this prototype's instability frequency from investigations on the reduced scale model. A new hydro acoustic vortex rope model has been developed in SIMSEN software, taking into account the energy dissipation due to the thermodynamic exchange between the gas and the surrounding liquid. A combination of measurements, CFD simulations and computation of eigenmodes of the reduced scale model installed on test rig, allows the accurate calibration of the vortex rope model parameters at the model scale. Then, transposition of parameters to the prototype according to similitude laws is applied and stability analysis of the power plant is performed. The eigenfrequency of 0.39 Hz related to the first eigenmode of the power plant is determined to be unstable. Predicted frequency of the full load power and pressure fluctuations at the unit unstable operating point is found to be in general agreement with the prototype measurements.

Prediction of a Francis turbine prototype full load instability from investigations on the reduced scale model

International Nuclear Information System (INIS)

Alligne, S; Maruzewski, P; Avellan, F; Dinh, T; Wang, B; Fedorov, A; Iosfin, J

2010-01-01

The growing development of renewable energies combined with the process of privatization, lead to a change of economical energy market strategies. Instantaneous pricings of electricity as a function of demand or predictions, induces profitable peak productions which are mainly covered by hydroelectric power plants. Therefore, operators harness more hydroelectric facilities at full load operating conditions. However, the Francis Turbine features an axi-symmetric rope leaving the runner which may act under certain conditions as an internal energy source leading to instability. Undesired power and pressure fluctuations are induced which may limit the maximum available power output. BC Hydro experiences such constraints in a hydroelectric power plant consisting of four 435 MW Francis Turbine generating units, which is located in Canada's province of British Columbia. Under specific full load operating conditions, one unit experiences power and pressure fluctuations at 0.46 Hz. The aim of the paper is to present a methodology allowing prediction of this prototype's instability frequency from investigations on the reduced scale model. A new hydro acoustic vortex rope model has been developed in SIMSEN software, taking into account the energy dissipation due to the thermodynamic exchange between the gas and the surrounding liquid. A combination of measurements, CFD simulations and computation of eigenmodes of the reduced scale model installed on test rig, allows the accurate calibration of the vortex rope model parameters at the model scale. Then, transposition of parameters to the prototype according to similitude laws is applied and stability analysis of the power plant is performed. The eigenfrequency of 0.39 Hz related to the first eigenmode of the power plant is determined to be unstable. Predicted frequency of the full load power and pressure fluctuations at the unit unstable operating point is found to be in general agreement with the prototype measurements.

Scaling cost-sharing to wages: how employers can reduce health spending and provide greater economic security.

Science.gov (United States)

Robertson, Christopher T

2014-01-01

In the employer-sponsored insurance market that covers most Americans; many workers are "underinsured." The evidence shows onerous out-of-pocket payments causing them to forgo needed care, miss work, and fall into bankruptcies and foreclosures. Nonetheless, many higher-paid workers are "overinsured": the evidence shows that in this domain, surplus insurance stimulates spending and price inflation without improving health. Employers can solve these problems together by scaling cost-sharing to wages. This reform would make insurance better protect against risk and guarantee access to care, while maintaining or even reducing insurance premiums. Yet, there are legal obstacles to scaled cost-sharing. The group-based nature of employer health insurance, reinforced by federal law, makes it difficult for scaling to be achieved through individual choices. The Affordable Care Act's (ACA) "essential coverage" mandate also caps cost-sharing even for wealthy workers that need no such cap. Additionally, there is a tax distortion in favor of highly paid workers purchasing healthcare through insurance rather than out-of-pocket. These problems are all surmountable. In particular, the ACA has expanded the applicability of an unenforced employee-benefits rule that prohibits "discrimination" in favor of highly compensated workers. A novel analysis shows that this statute gives the Internal Revenue Service the authority to require scaling and to thereby eliminate the current inequities and inefficiencies caused by the tax distortion. The promise is smarter insurance for over 150 million Americans.

A Two-Scale Reduced Model for Darcy Flow in Fractured Porous Media

KAUST Repository

Chen, Huangxin; Sun, Shuyu

2016-01-01

scale, and the effect of fractures on each coarse scale grid cell intersecting with fractures is represented by the discrete fracture model (DFM) on the fine scale. In the DFM used on the fine scale, the matrix-fracture system are resolved

Small scale models equal large scale savings

International Nuclear Information System (INIS)

Lee, R.; Segroves, R.

1994-01-01

A physical scale model of a reactor is a tool which can be used to reduce the time spent by workers in the containment during an outage and thus to reduce the radiation dose and save money. The model can be used for worker orientation, and for planning maintenance, modifications, manpower deployment and outage activities. Examples of the use of models are presented. These were for the La Salle 2 and Dresden 1 and 2 BWRs. In each case cost-effectiveness and exposure reduction due to the use of a scale model is demonstrated. (UK)

Preparation of Nano-Scale Biopolymer Extracted from Coconut Residue and Its Performance as Drag Reducing Agent (DRA

Directory of Open Access Journals (Sweden)

Hasan Muhammad Luqman Bin

2017-01-01

Full Text Available Drag or frictional force is defined as force that acts opposite to the object’s relative motion through a fluid which then will cause frictional pressure loss in the pipeline. Drag Reducing Agent (DRA is used to solve this issue and most of the DRAs are synthetic polymers but has some environmental issues. Therefore for this study, biopolymer known as Coconut Residue (CR is selected as the candidate to replace synthetic polymers DRA. The objective of this study is to evaluate the effectiveness of Nano-scale biopolymer DRA on the application of water injection system. Carboxymethyl cellulose (CMC is extracted by synthesizing the cellulose extracted from CR under the alkali-catalyzed reaction using monochloroacetic acid. The synthesize process is held in controlled condition whereby the concentration of NaOH is kept at 60%wt, 60 °C temperature and the reaction time is 4 hours. For every 25 g of dried CR used, the mass of synthesized CMC yield is at an average of 23.8 g. The synthesized CMC is then grinded in controlled parameters using the ball milling machine to get the Nano-scale size. The particle size obtained from this is 43.32 Nm which is in range of Nano size. This study proved that Nano-size CMC has higher percentage of drag reduction (%DR and flow increase (%FI if compared to normal-size CMC when tested in high and low flow rate; 44% to 48% increase in %DR and %FI when tested in low flow rate, and 16% to 18% increase in %DR and %FI when tested in high flow rate. The success of this research shows that Nano-scale DRA can be considered to be used to have better performance in reducing drag.

Application of Bacillus sp. TAT105 to reduce ammonia emissions during pilot-scale composting of swine manure.

Science.gov (United States)

Kuroda, Kazutaka; Tanaka, Akihiro; Furuhashi, Kenich; Nakasaki, Kiyohiko

2017-12-01

Thermophilic ammonium-tolerant bacterium Bacillus sp. TAT105 grows and reduces ammonia (NH 3 ) emissions by assimilating ammonium nitrogen during composting of swine feces. To evaluate the efficacy of a biological additive containing TAT105 at reducing NH 3 emissions, composting tests of swine manure on a pilot scale (1.8 m 3 ) were conducted. In the TAT105-added treatment, NH 3 emissions and nitrogen loss were lower than those in the control treatment without TAT105. No significant difference was detected in losses in the weight and volatile solids between the treatments. Concentration of thermophilic ammonium-tolerant bacteria in the compost increased in both treatments at the initial stage of composting. In the TAT105-added treatment, bacterial concentration reached ~10 9 colony-forming units per gram of dry matter, several-fold higher than that in the control and stayed at the same level until the end. These results suggest that TAT105 grows during composting and reduces NH 3 emissions in TAT105-added treatment.

Impact evaluation of the large scale integration of electric vehicles in the security of supply

Science.gov (United States)

Bremermann, Leonardo Elizeire

As piroxenas sao um vasto grupo de silicatos minerais encontrados em muitas rochas igneas e metamorficas. Na sua forma mais simples, estes silicatos sao constituidas por cadeias de SiO3 ligando grupos tetrahedricos de SiO4. A formula quimica geral das piroxenas e M2M1T2O6, onde M2 se refere a catioes geralmente em uma coordenacao octaedrica distorcida (Mg2+, Fe2+, Mn2+, Li+, Ca2+, Na+), M1 refere-se a catioes numa coordenacao octaedrica regular (Al3+, Fe3+, Ti4+, Cr3+, V3+, Ti3+, Zr4+, Sc3+, Zn2+, Mg2+, Fe2+, Mn2+), e T a catioes em coordenacao tetrahedrica (Si4+, Al3+, Fe3+). As piroxenas com estrutura monoclinica sao designadas de clinopiroxenes. A estabilidade das clinopyroxenes num espectro de composicoes quimicas amplo, em conjugacao com a possibilidade de ajustar as suas propriedades fisicas e quimicas e a durabilidade quimica, tem gerado um interesse mundial devido a suas aplicacoes em ciencia e tecnologia de materiais. Este trabalho trata do desenvolvimento de vidros e de vitro-cerâmicos baseadas de clinopiroxenas para aplicacoes funcionais. O estudo teve objectivos cientificos e tecnologicos; nomeadamente, adquirir conhecimentos fundamentais sobre a formacao de fases cristalinas e solucoes solidas em determinados sistemas vitro-cerâmicos, e avaliar a viabilidade de aplicacao dos novos materiais em diferentes areas tecnologicas, com especial enfase sobre a selagem em celulas de combustivel de oxido solido (SOFC). Com este intuito, prepararam-se varios vidros e materiais vitro-cerâmicos ao longo das juntas Enstatite (MgSiO3) - diopsidio (CaMgSi2O6) e diopsidio (CaMgSi2O6) - Ca - Tschermak (CaAlSi2O6), os quais foram caracterizados atraves de um vasto leque de tecnicas. Todos os vidros foram preparados por fusao-arrefecimento enquanto os vitro-cerâmicos foram obtidos quer por sinterizacao e cristalizacao de fritas, quer por nucleacao e cristalizacao de vidros monoliticos. Estudaram-se ainda os efeitos de varias substituicoes ionicas em composicoes de

Influence of PCMs on thermal behavior of building walls: experimental study using the walls of a reduced scale room

Directory of Open Access Journals (Sweden)

Gounni Ayoub

2017-01-01

Full Text Available Using Phase-Change Materials (PCM for lightweight building applications can increase equivalent thermal mass and provide energy savings. In the present experimental work, the heat transfer performance testing of some building walls, with or without PCM, is carried out using a reduced-scale cubic room (the test-cell. The cubic cell is heated by an incandescent bulb placed on its centre, and it is housed in an air-conditioned large-scale room that allows to control the ambient air temperature. The effect of the double PCM layer and of its location relatively to the outside surface of the wall is tested and discussed in terms of overall transmitted heat flux and in terms of reduction of the inside and outside surface temperatures. Findings shows that the additional inertia introduced by the PCM leads to a reduced overall heat flux transmission by the wall and to a lesser daily temperature amplitude on the surface of the wall that enhances the thermal comfort inside the building. In the next step of this work, the case of sandwich walls with air gap, and with wood and PCM layers will be considered.

Influence of PCMs on thermal behavior of building walls: experimental study using the walls of a reduced scale room

Science.gov (United States)

Gounni, Ayoub; Tahar Mabrouk, Mohamed; Kheiri, Abdelhamid; El alami, Mustapha

2017-11-01

Using Phase-Change Materials (PCM) for lightweight building applications can increase equivalent thermal mass and provide energy savings. In the present experimental work, the heat transfer performance testing of some building walls, with or without PCM, is carried out using a reduced-scale cubic room (the test-cell). The cubic cell is heated by an incandescent bulb placed on its centre, and it is housed in an air-conditioned large-scale room that allows to control the ambient air temperature. The effect of the double PCM layer and of its location relatively to the outside surface of the wall is tested and discussed in terms of overall transmitted heat flux and in terms of reduction of the inside and outside surface temperatures. Findings shows that the additional inertia introduced by the PCM leads to a reduced overall heat flux transmission by the wall and to a lesser daily temperature amplitude on the surface of the wall that enhances the thermal comfort inside the building. In the next step of this work, the case of sandwich walls with air gap, and with wood and PCM layers will be considered.

Smoke flow temperature beneath tunnel ceiling for train fire at subway station: Reduced-scale experiments and correlations

International Nuclear Information System (INIS)

Meng, Na; Wang, Qiang; Liu, Zhaoxia; Li, Xiao; Yang, He

2017-01-01

Highlights: • Reduced-scale experiments on train fire at subway station. • Smoke flow temperature beneath tunnel ceiling measured and correlated. • Effect of platform-tunnel conjunction door type on smoke temperature is clarified. - Abstract: This paper is to investigate the smoke flow temperature beneath tunnel ceiling for a train on fire stopping besides a subway station. Experiments were carried out in a reduced-scale (1:10) subway station model to study the maximum smoke temperature and the longitudinal temperature distribution beneath the tunnel ceiling by considering platform-tunnel conjunction doors of two types: the full-seal platform screen door (PSD) and the full-height safety door. For the maximum temperature beneath the tunnel ceiling, it is found to be well correlated non-dimensionally with heat release rate by a 3.65 and a 2.92 power law function for the full-seal platform screen door and the full-height safety door, respectively. For the longitudinal temperature distribution along the tunnel ceiling, it can be well correlated by an exponential function for both types of platform-tunnel conjunction doors. Concerning the effect of the door type, the maximum temperature is lower and the longitudinal temperature decays faster for full-height safety door than that for full-seal PSD. This is due to that with the full-height safety door, the effective width of the tunnel ceiling is widened, which results in more heat losses from the smoke flow to the ceiling.

Structural evaluation of spent nuclear fuel storage facilities under aircraft crash impact (2). Horizontal impact test onto reduced scale metal cask due to aircraft engine missile

International Nuclear Information System (INIS)

Namba, Kosuke; Shirai, Koji; Saegusa, Toshiari

2009-01-01

In this study, to confirm the sealing performance of a metal cask subjected to impact force due to possible commercial aircraft crash against a spent fuel storage facility, the horizontal impact test was carried out. In the test, an aircraft engine missile with a speed of 57.3 m/s attacked the reduced scale metal cask containing helium gas, which stands vertically. Then the leak rate and sliding displacement of the lid were measured. The leak rate increased rapidly and reached to 4.0 x 10 -6 Pa·m 3 /sec. After that, the leak rate decreased slowly and converged to 1.0x10 -6 Pa·m 3 /sec after 20 hours from the impact test. The leak rate of a full scale cask was evaluated using that of reduced scale cask obtained by the test. Then the leak rate of the full scale cask was 3.5x10 -5 Pa·m 3 /sec. This result showed that the sealing performance of the full scale metal cask would not be affected immediately by the horizontal impact of the aircraft engine with a speed of 57.3 m/s. (author)

SCALING ANALYSIS OF REPOSITORY HEAT LOAD FOR REDUCED DIMENSIONALITY MODELS

International Nuclear Information System (INIS)

MICHAEL T. ITAMUA AND CLIFFORD K. HO

1998-01-01

The thermal energy released from the waste packages emplaced in the potential Yucca Mountain repository is expected to result in changes in the repository temperature, relative humidity, air mass fraction, gas flow rates, and other parameters that are important input into the models used to calculate the performance of the engineered system components. In particular, the waste package degradation models require input from thermal-hydrologic models that have higher resolution than those currently used to simulate the T/H responses at the mountain-scale. Therefore, a combination of mountain- and drift-scale T/H models is being used to generate the drift thermal-hydrologic environment

Modelling the ability of source control measures to reduce inundation risk in a community-scale urban drainage system

Science.gov (United States)

Mei, Chao; Liu, Jiahong; Wang, Hao; Shao, Weiwei; Xia, Lin; Xiang, Chenyao; Zhou, Jinjun

2018-06-01

Urban inundation is a serious challenge that increasingly confronts the residents of many cities, as well as policymakers, in the context of rapid urbanization and climate change worldwide. In recent years, source control measures (SCMs) such as green roofs, permeable pavements, rain gardens, and vegetative swales have been implemented to address flood inundation in urban settings, and proven to be cost-effective and sustainable. In order to investigate the ability of SCMs on reducing inundation in a community-scale urban drainage system, a dynamic rainfall-runoff model of a community-scale urban drainage system was developed based on SWMM. SCMs implementing scenarios were modelled under six design rainstorm events with return period ranging from 2 to 100 years, and inundation risks of the drainage system were evaluated before and after the proposed implementation of SCMs, with a risk-evaluation method based on SWMM and analytic hierarchy process (AHP). Results show that, SCMs implementation resulting in significantly reduction of hydrological indexes that related to inundation risks, range of reduction rates of average flow, peak flow, and total flooded volume of the drainage system were 28.1-72.1, 19.0-69.2, and 33.9-56.0 %, respectively, under six rainfall events with return periods ranging from 2 to 100 years. Corresponding, the inundation risks of the drainage system were significantly reduced after SCMs implementation, the risk values falling below 0.2 when the rainfall return period was less than 10 years. Simulation results confirm the effectiveness of SCMs on mitigating inundation, and quantified the potential of SCMs on reducing inundation risks in the urban drainage system, which provided scientific references for implementing SCMs for inundation control of the study area.

Multi-scale path planning for reduced environmental impact of aviation

Science.gov (United States)

Campbell, Scot Edward

A future air traffic management system capable of rerouting aircraft trajectories in real-time in response to transient and evolving events would result in increased aircraft efficiency, better utilization of the airspace, and decreased environmental impact. Mixed-integer linear programming (MILP) is used within a receding horizon framework to form aircraft trajectories which mitigate persistent contrail formation, avoid areas of convective weather, and seek a minimum fuel solution. Areas conducive to persistent contrail formation and areas of convective weather occur at disparate temporal and spatial scales, and thereby require the receding horizon controller to be adaptable to multi-scale events. In response, a novel adaptable receding horizon controller was developed to account for multi-scale disturbances, as well as generate trajectories using both a penalty function approach for obstacle penetration and hard obstacle avoidance constraints. A realistic aircraft fuel burn model based on aircraft data and engine performance simulations is used to form the cost function in the MILP optimization. The performance of the receding horizon algorithm is tested through simulation. A scalability analysis of the algorithm is conducted to ensure the tractability of the path planner. The adaptable receding horizon algorithm is shown to successfully negotiate multi-scale environments with performance exceeding static receding horizon solutions. The path planner is applied to realistic scenarios involving real atmospheric data. A single flight example for persistent contrail mitigation shows that fuel burn increases 1.48% when approximately 50% of persistent contrails are avoided, but 6.19% when 100% of persistent contrails are avoided. Persistent contrail mitigating trajectories are generated for multiple days of data, and the research shows that 58% of persistent contrails are avoided with a 0.48% increase in fuel consumption when averaged over a year.

Validation of a methodology to develop a test facility in reduced scale related to boron dispersion in a pressurizer of an iPWR

Energy Technology Data Exchange (ETDEWEB)

Nascimento, Samira R.V.; Lira, Carlos A.B.O.; Lapa, Celso M.F.; Lima, Fernando R.A.; Bezerra, Jair L.; Silva, Mário A.B., E-mail: cabol@ufpe.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Centro de Tecnologia e Geociências. Departamento de Energia Nuclear; Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Centro Regional de Ciências Nucleares do Nordeste (CRCN/CNEN-PE), Recife, PE (Brazil)

2017-11-01

The conception and the project of a 1:200 reduced scale test facility have been developed in earlier researches. Such a facility aims to investigate boron homogenization process inside the pressurizer of an iPWR (integral PWR) by considering water mixing from this component with that coming from the reactor core. For this kind of reactor, the pressurizer is located at the top of the pressure vessel demanding the need of identifying the proper mechanisms in order to warrant an adequate homogenization for the water mixture. Once the installation of the experimental setup was concluded, its behavior has been analyzed by considering the concentration of a tracer diluted in the circulation water, whose measurements were obtained at the pressurizer outlet orifices. Two experiments representing boration(boron concentration increase)/deboration(boron concentration decrease) scenarios have been accomplished. Sample acquisition was carried out for every ten minutes during a total time equal to 180 minutes. Results showed that the combination of Fractional Scaling Analysis with local Froude number consisted of an appropriate methodology to provide the reduced scale test facility parameters, inasmuch the measured concentrations from the experiments reproduced the theoretical behavior with sufficient accuracy. (author)

Validation of a methodology to develop a test facility in reduced scale related to boron dispersion in a pressurizer of an iPWR

International Nuclear Information System (INIS)

Nascimento, Samira R.V.; Lira, Carlos A.B.O.; Lapa, Celso M.F.; Lima, Fernando R.A.; Bezerra, Jair L.; Silva, Mário A.B.

2017-01-01

The conception and the project of a 1:200 reduced scale test facility have been developed in earlier researches. Such a facility aims to investigate boron homogenization process inside the pressurizer of an iPWR (integral PWR) by considering water mixing from this component with that coming from the reactor core. For this kind of reactor, the pressurizer is located at the top of the pressure vessel demanding the need of identifying the proper mechanisms in order to warrant an adequate homogenization for the water mixture. Once the installation of the experimental setup was concluded, its behavior has been analyzed by considering the concentration of a tracer diluted in the circulation water, whose measurements were obtained at the pressurizer outlet orifices. Two experiments representing boration(boron concentration increase)/deboration(boron concentration decrease) scenarios have been accomplished. Sample acquisition was carried out for every ten minutes during a total time equal to 180 minutes. Results showed that the combination of Fractional Scaling Analysis with local Froude number consisted of an appropriate methodology to provide the reduced scale test facility parameters, inasmuch the measured concentrations from the experiments reproduced the theoretical behavior with sufficient accuracy. (author)

Biogeochemistry of a Field-Scale Sulfate Reducing Bioreactor Treating Mining Influenced Water

Science.gov (United States)

Drennan, D.; Lee, I.; Landkamer, L.; Figueroa, L. A.; Webb, S.; Sharp, J. O.

2012-12-01

Acidity, metal release, and toxicity may be environmental health concerns in areas influenced by mining. Mining influenced waters (MIW) can be remediated through the establishment of Sulfate Reducing Bioreactors (SRBRs) as part of engineered passive treatment systems. The objective of our research is an enhanced understanding of the biogeochemistry in SRBRs by combining molecular biological and geochemical techniques. Bioreactor reactive substrate, settling pond water, and effluent (from the SRBR) were collected from a field scale SRBR in Arizona, which has been in operation for approximately 3 years. Schematically, the water passes through the SRBR; combines with flow that bypasses the SRBR into the and goes into the mixing pond, and finally is released as effluent to aerobic polishing cells. High throughput sequencing of extracted DNA revealed that Proteobacteria dominated the reactive substrate (61%), settling pond (93%), and effluent (50%), with the next most abundant phylum in all samples (excluding uncultured organisms) being Bacteriodes (1-17%). However, at the superclass level, the three samples were more variable. Gammaproteobacteria dominated the reactive substrate (35%), Betaproteobacteria in the settling pond (63%) and finally the effluent was dominated by Epsilonproteobacteria (Helicobacteraceae) (43%). Diversity was most pronounced in association with the reactor matrix, and least diverse in the settling pond. Putative functional analysis revealed a modest presence of sulfate/sulfur reducing bacteria (SRB) (>5%) in both the matrix and settling pond but a much higher abundance (43%) of sulfur reducing bacteria in the effluent. Interestingly this effluent population was composed entirely of the family Helicobacteraceae (sulfur reduction II via polysulfide pathway). Other putative functions of interest include metal reduction in the matrix (3%) and effluent (3%), as well as polysaccharide degradation, which was largely abundant in all samples (21

An Experimental Study on Burning Characteristics of n-Heptane/Ethanol Mixture Pool Fires in a Reduced Scaled Tunnel

Science.gov (United States)

Yozgatligil, Ahmet; Shafee, Sina

2016-11-01

Fire accidents in recent decades have drawn attention to safety issues associated with the design, construction and maintenance of tunnels. A reduced scale tunnel model constructed based on Froude scaling technique is used in the current work. Mixtures of n-heptane and ethanol are burned with ethanol volumetric fraction up to 30 percent and the longitudinal ventilation velocity varying from 0.5 to 2.5 m/s. The burning rates of the pool fires are measured using a precision load cell. The heat release rates of the fires are calculated according to oxygen calorimetry method and the temperature distributions inside the tunnel are also measured. Results of the experiments show that the ventilation velocity variation has a significant effect on the pool fire burning rate, smoke temperature and the critical ventilation velocity. With increased oxygen depletion in case of increased ethanol content of blended pool fires, the quasi-steady heat release rate values tend to increase as well as the ceiling temperatures while the combustion duration decreases.

Reduced dimer production in solar-simulator-pumped continuous wave iodine lasers based on model simulations and scaling and pumping studies

Science.gov (United States)

Costen, Robert C.; Heinbockel, John H.; Miner, Gilda A.; Meador, Willard E., Jr.; Tabibi, Bagher M.; Lee, Ja H.; Williams, Michael D.

1995-01-01

A numerical rate equation model for a continuous wave iodine laser with longitudinally flowing gaseous lasant is validated by approximating two experiments that compare the perfluoroalkyl iodine lasants n-C3F7I and t-C4F9I. The salient feature of the simulations is that the production rate of the dimer (C4F9)2 is reduced by one order of magnitude relative to the dimer (C3F7)2. The model is then used to investigate the kinetic effects of this reduced dimer production, especially how it improves output power. Related parametric and scaling studies are also presented. When dimer production is reduced, more monomer radicals (t-C4F9) are available to combine with iodine ions, thus enhancing depletion of the laser lower level and reducing buildup of the principal quencher, molecular iodine. Fewer iodine molecules result in fewer downward transitions from quenching and more transitions from stimulated emission of lasing photons. Enhanced depletion of the lower level reduces the absorption of lasing photons. The combined result is more lasing photons and proportionally increased output power.

Experimental results of the SMART ECC injection performance with reduced scale of test facility

Energy Technology Data Exchange (ETDEWEB)

Cho, Young Il; Cho, Seok; Ko, Yung Joo; Shin, Yong Cheol; Kwon, Tae Soon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2011-05-15

SMART pressurized water reactor type is different from the existing integral NSSS commercial pressurized water reactor system which is equipped with the main features. In addition, RCS piping is removed and the feature of the SBLOCA is a major design break accident. SWAT (SMART ECC Water Asymmetric Two-phase choking test facility) test facility is to simulate the 2 inch SBLOCA of the SMART using with reduced scale. The Test was performed to produce experimental data for the validation of the TASS/SMR-S thermal hydraulic analysis code, and to investigate the related thermal hydraulic phenomena in the down-comer region during the 2 inch SBLOCA of the safety inject line. The particular phenomena for the observation are ECC bypass and multi-dimensional flow characteristics to verify the effectiveness and performance of the safety injection system. In this paper, the corresponding steady state test conditions, including initial and boundary conditions along with major measuring parameters, and related experimental results were described

Basic investigation of particle swarm optimization performance in a reduced scale PWR passive safety system design

International Nuclear Information System (INIS)

Cunha, Joao J. da; Lapa, Celso Marcelo F.; Alvim, Antonio Carlos M.; Lima, Carlos A. Souza; Pereira, Claudio Marcio do N.A.

2010-01-01

This work presents a methodology to investigate the viability of using particle swarm optimization technique to obtain the best combination of physical and operational parameters that lead to the best adjusted dimensionless groups, calculated by similarity laws, that are able to simulate the most relevant physical phenomena in single-phase flow under natural circulation and to offer an appropriate alternative reduced scale design for reactor primary loops with this flow characteristics. A PWR reactor core, under natural circulation, based on LOFT test facility, was used as the case study. The particle swarm optimization technique was applied to a problem with these thermo-hydraulics conditions and results demonstrated the viability and adequacy of the method to design similar systems with these characteristics.

Basic investigation of particle swarm optimization performance in a reduced scale PWR passive safety system design

Energy Technology Data Exchange (ETDEWEB)

Cunha, Joao J. da [Eletronuclear Eletrobras Termonuclear, Gerencia de Analise de Seguranca Nuclear, Rua da Candelaria, 65, 7o andar. Centro, Rio de Janeiro 20091-906 (Brazil); Lapa, Celso Marcelo F., E-mail: lapa@ien.gov.b [Instituto de Engenharia Nuclear, Divisao de Reatores/PPGIEN, P.O. Box 68550, Rua Helio de Almeida 75 Cidade Universitaria, Ilha do Fundao, Rio de Janeiro 21941-972 (Brazil); Instituto Nacional de Ciencia e Tecnologia de Reatores Nucleares Inovadores (Brazil); Alvim, Antonio Carlos M. [Universidade Federal do Rio de Janeiro, COPPE/Nuclear, P.O. Box 68509, Cidade Universitaria, Ilha do Fundao s/n, Rio de Janeiro 21945-970 (Brazil); Instituto Nacional de Ciencia e Tecnologia de Reatores Nucleares Inovadores (Brazil); Lima, Carlos A. Souza [Instituto de Engenharia Nuclear, Divisao de Reatores/PPGIEN, P.O. Box 68550, Rua Helio de Almeida 75 Cidade Universitaria, Ilha do Fundao, Rio de Janeiro 21941-972 (Brazil); Instituto Politecnico, Universidade do Estado do Rio de Janeiro, Pos-Graduacao em Modelagem Computacional, Rua Alberto Rangel, s/n, Vila Nova, Nova Friburgo 28630-050 (Brazil); Pereira, Claudio Marcio do N.A. [Instituto de Engenharia Nuclear, Divisao de Reatores/PPGIEN, P.O. Box 68550, Rua Helio de Almeida 75 Cidade Universitaria, Ilha do Fundao, Rio de Janeiro 21941-972 (Brazil); Instituto Nacional de Ciencia e Tecnologia de Reatores Nucleares Inovadores (Brazil)

2010-03-15

This work presents a methodology to investigate the viability of using particle swarm optimization technique to obtain the best combination of physical and operational parameters that lead to the best adjusted dimensionless groups, calculated by similarity laws, that are able to simulate the most relevant physical phenomena in single-phase flow under natural circulation and to offer an appropriate alternative reduced scale design for reactor primary loops with this flow characteristics. A PWR reactor core, under natural circulation, based on LOFT test facility, was used as the case study. The particle swarm optimization technique was applied to a problem with these thermo-hydraulics conditions and results demonstrated the viability and adequacy of the method to design similar systems with these characteristics.

How could the family-scale photovoltaic module help the poor farmer out of poverty and reduce CO2 emission?

Science.gov (United States)

Qiu, Xu; Jin, Ran

2016-04-01

China, the world's most populous country, is facing great opportunities and challenges. On the one hand, China's increasing economy is raising hundreds of millions of people out of poverty. On the other hand, there are still 100 million of whose daily income is less than 1 US dollar. In addition, China is the world's largest solar panel producer and also the largest emitter of greenhouse gases. Could we find a feasible way to use solar panels to help the poor and meanwhile reduce CO2 emissions? To do this, we reviewed the literature and investigated the related field sites and institutions in China. Results show that the extension of family-scale photovoltaic modules to countryside could help. The 3 kW-module is recommended for widely distribution because its technology is mature and the cost is relatively low (3500 US dollars). Besides their own use to improve their living standard, farmers can sell the excess electricity to the grid at the price of 0.17 UD/kWh. The farmer's annual income could be increased by 460-615 US dollars by selling electricity, and this is equivalent to half of their annual income in many rural regions. The photovoltaic module can be used for 25 years and the payback period is 7 years. In addition to its economic benefit, the photovoltaic module can reduce CO2 emissions by 0.93 kg/kWh. This is equivalent to annual reduction of 3000-4000 kg CO2 per family. Therefore, it is concluded that the family-scale photovoltaic module not only can help the farmers out of poverty but also can reduce CO2 emissions significantly. To promote its sustainable development, it is worthwhile to further investigations its business models as well as the effects of long-term support policies under different social and nature conditions.

Considerations for reducing food system energy demand while scaling up urban agriculture

Science.gov (United States)

Mohareb, Eugene; Heller, Martin; Novak, Paige; Goldstein, Benjamin; Fonoll, Xavier; Raskin, Lutgarde

2017-12-01

There is an increasing global interest in scaling up urban agriculture (UA) in its various forms, from private gardens to sophisticated commercial operations. Much of this interest is in the spirit of environmental protection, with reduced waste and transportation energy highlighted as some of the proposed benefits of UA; however, explicit consideration of energy and resource requirements needs to be made in order to realize these anticipated environmental benefits. A literature review is undertaken here to provide new insight into the energy implications of scaling up UA in cities in high-income countries, considering UA classification, direct/indirect energy pressures, and interactions with other components of the food-energy-water nexus. This is followed by an exploration of ways in which these cities can plan for the exploitation of waste flows for resource-efficient UA. Given that it is estimated that the food system contributes nearly 15% of total US energy demand, optimization of resource use in food production, distribution, consumption, and waste systems may have a significant energy impact. There are limited data available that quantify resource demand implications directly associated with UA systems, highlighting that the literature is not yet sufficiently robust to make universal claims on benefits. This letter explores energy demand from conventional resource inputs, various production systems, water/energy trade-offs, alternative irrigation, packaging materials, and transportation/supply chains to shed light on UA-focused research needs. By analyzing data and cases from the existing literature, we propose that gains in energy efficiency could be realized through the co-location of UA operations with waste streams (e.g. heat, CO2, greywater, wastewater, compost), potentially increasing yields and offsetting life cycle energy demands relative to conventional approaches. This begs a number of energy-focused UA research questions that explore the

Sediment filtration can reduce the N load of the waste water discharge - a full-scale lake experiment

Science.gov (United States)

Aalto, Sanni L.; Saarenheimo, Jatta; Karvinen, Anu; Rissanen, Antti J.; Ropponen, Janne; Juntunen, Janne; Tiirola, Marja

2016-04-01

European commission has obliged Baltic states to reduce nitrate load, which requires high investments on the nitrate removal processes and may increase emissions of greenhouse gases, e.g. N2O, in the waste water treatment plants. We used ecosystem-scale experimental approach to test a novel sediment filtration method for economical waste water N removal in Lake Keurusselkä, Finland between 2014 and 2015. By spatially optimizing the waste water discharge, the contact area and time of nitrified waste water with the reducing microbes of the sediment was increased. This was expected to enhance microbial-driven N transformation and to alter microbial community composition. We utilized 15N isotope pairing technique to follow changes in the actual and potential denitrification rates, nitrous oxide formation and dissimilatory nitrate reduction to ammonium (DNRA) in the lake sediments receiving nitrate-rich waste water input and in the control site. In addition, we investigated the connections between observed process rates and microbial community composition and functioning by using next generation sequencing and quantitative PCR. Furthermore, we estimated the effect of sediment filtration method on waste water contact time with sediment using the 3D hydrodynamic model. We sampled one year before the full-scale experiment and observed strong seasonal patterns in the process rates, which reflects the seasonal variation in the temperature-related mixing patterns of the waste water within the lake. During the experiment, we found that spatial optimization enhanced both actual and potential denitrification rates of the sediment. Furthermore, it did not significantly promote N2O emissions, or N retention through DNRA. Overall, our results indicate that sediment filtration can be utilized as a supplemental or even alternative method for the waste water N removal.

Allergen sanitation in the food industry: a systematic industrial scale approach to reduce hazelnut cross-contamination of cookies.

Science.gov (United States)

Röder, Martin; Baltruweit, Iris; Gruyters, Helwig; Ibach, Anja; Mücke, Ingo; Matissek, Reinhard; Vieths, Stefan; Holzhauser, Thomas

2010-09-01

Recently, we investigated the impact of shared equipment on cross-contamination of cookies at a pilot plant scale. Based on those findings, this study investigated the extent and subsequent sanitation of hazelnut cross-contamination (HNCC) of cookies at the industrial scale. Similarly, a product change from cookies with hazelnut ingredient to cookies without hazelnut was performed on standard equipment. HNCC in the hazelnut-free follow-up product was quantified by enzyme-linked immunosorbent assay for each production device and the applied cleaning procedure. All experiments were repeated in duplicate. The highest HNCC was found in concordance with previous studies after mere mechanical scraping: more than 1,000 mg of hazelnut protein per kg was quantified in the follow-up product after processing by a cookie machine. Additional cleaning with hot water decreased the HNCC irrespective of the processing device to levels at or below 1 mg of hazelnut protein per kg. Furthermore, raw materials for cookie production were monitored over a period of 24 months for unwanted preloads of hazelnut and peanut: hazelnut was quantified in 16% of the investigated raw materials as being between 0.26 and 90 mg/kg. Further critical control points at the industrial scale, where cross-contamination might occur, were identified but did not display noteworthy sources of cross-contamination. In conclusion, the quantitative monitoring of the cleaning efficiency at the industrial scale confirmed the procedure of manual scraping plus wet cleaning as a qualified sanitation procedure to effectively reduce the hazelnut protein cross-contamination down to a level at which severe hazelnut-related allergic reactions are unlikely to occur.

SCALE INTERACTION IN A MIXING LAYER. THE ROLE OF THE LARGE-SCALE GRADIENTS

KAUST Repository

Fiscaletti, Daniele

2015-08-23

The interaction between scales is investigated in a turbulent mixing layer. The large-scale amplitude modulation of the small scales already observed in other works depends on the crosswise location. Large-scale positive fluctuations correlate with a stronger activity of the small scales on the low speed-side of the mixing layer, and a reduced activity on the high speed-side. However, from physical considerations we would expect the scales to interact in a qualitatively similar way within the flow and across different turbulent flows. Therefore, instead of the large-scale fluctuations, the large-scale gradients modulation of the small scales has been additionally investigated.

Single and two-phase similarity analysis of a reduced-scale natural convection loop relative to a full-scale prototype

International Nuclear Information System (INIS)

Botelho, David A.; Faccini, Jose L.H.

2002-01-01

The main topic in this paper is a new device being considered to improve nuclear reactor safety employing the natural circulation. A scaled experiment used to demonstrate the performance of the device is also described. We also applied a similarity analysis method for single and two-phase natural convection loop flow to the IEN CCN experiment and to an APEX like experiment to verify the degree of similarity relative to a full-scale prototype like the AP600. Most of the CCN similarity numbers that represent important single and two-phase similarity conditions are comparable to the APEX like loop non-dimensional numbers calculated employing the same methodology. Despite the much smaller geometric, pressure, and power scales, we conclude that the IEN CCN has single and two-phase natural circulation similarity numbers that represent fairly well the full-scale prototype. even lacking most complementary primary and safety systems, this IEN circuit provided a much valid experience to develop human, experimental, and analytical resources, besides its utilization as a training tool. (author)

Gravo-Aeroelastic Scaling for Extreme-Scale Wind Turbines

Energy Technology Data Exchange (ETDEWEB)

Fingersh, Lee J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Loth, Eric [University of Virginia; Kaminski, Meghan [University of Virginia; Qin, Chao [University of Virginia; Griffith, D. Todd [Sandia National Laboratories

2017-06-09

A scaling methodology is described in the present paper for extreme-scale wind turbines (rated at 10 MW or more) that allow their sub-scale turbines to capture their key blade dynamics and aeroelastic deflections. For extreme-scale turbines, such deflections and dynamics can be substantial and are primarily driven by centrifugal, thrust and gravity forces as well as the net torque. Each of these are in turn a function of various wind conditions, including turbulence levels that cause shear, veer, and gust loads. The 13.2 MW rated SNL100-03 rotor design, having a blade length of 100-meters, is herein scaled to the CART3 wind turbine at NREL using 25% geometric scaling and blade mass and wind speed scaled by gravo-aeroelastic constraints. In order to mimic the ultralight structure on the advanced concept extreme-scale design the scaling results indicate that the gravo-aeroelastically scaled blades for the CART3 are be three times lighter and 25% longer than the current CART3 blades. A benefit of this scaling approach is that the scaled wind speeds needed for testing are reduced (in this case by a factor of two), allowing testing under extreme gust conditions to be much more easily achieved. Most importantly, this scaling approach can investigate extreme-scale concepts including dynamic behaviors and aeroelastic deflections (including flutter) at an extremely small fraction of the full-scale cost.

Self-adapted sliding scale spectroscopy ADC

International Nuclear Information System (INIS)

Xu Qichun; Wang Jingjin

1992-01-01

The traditional sliding scale technique causes a disabled range that is equal to the sliding length, thus reduces the analysis range of a MCA. A method for reduce ADC's DNL, which is called self-adapted sliding scale method, has been designed and tested. With this method, the disabled range caused by a traditional sliding scale method can be eliminated by a random trial scale and there is no need of an additional amplitude discriminator with swing threshold. A special trial-and-correct logic is presented. The tested DNL of the spectroscopy ADC described here is less than 0.5%

Thermal properties of graphite oxide, thermally reduced graphene and chemically reduced graphene

Science.gov (United States)

Jankovský, Ondřej; Sedmidubský, David; Lojka, Michal; Sofer, Zdeněk

2017-07-01

We compared thermal behavior and other properties of graphite oxide, thermally reduced graphene and chemically reduced graphene. Graphite was oxidized according to the Hofmann method using potassium chlorate as oxidizing agent in strongly acidic environment. In the next step, the formed graphite oxide was chemically or thermally reduced yielding graphene. The mechanism of thermal reduction was studied using STA-MS. Graphite oxide and both thermally and chemically reduced graphenes were analysed by SEM, EDS, elemental combustion analysis, XPS, Raman spectroscopy, XRD and BET. These findings will help for the large scale production of graphene with appropriate chemical composition.

Process for reducing the pertechnetate anion

International Nuclear Information System (INIS)

Ruddock, C.F.

1980-01-01

Process for reducing the 'pertechnetate' ion TcO 4 - , whereby an aqueous solution of 'pertechnetate' is mixed with tin metal or a tin alloy as 'pertechnetate' reducing agent, and a soluble salt of a metal below tin in the electro-chemical tension scale, as activator for the reducing tin. This reduced 'pertechnetate' is used for forming usable complexes in medical diagnosis exploration [fr

Innovative Method for Automatic Shape Generation and 3D Printing of Reduced-Scale Models of Ultra-Thin Concrete Shells

Directory of Open Access Journals (Sweden)

Ana Tomé

2018-02-01

Full Text Available A research and development project has been conducted aiming to design and produce ultra-thin concrete shells. In this paper, the first part of the project is described, consisting of an innovative method for shape generation and the consequent production of reduced-scale models of the selected geometries. First, the shape generation is explained, consisting of a geometrically nonlinear analysis based on the Finite Element Method (FEM to define the antifunicular of the shell’s deadweight. Next, the scale model production is described, consisting of 3D printing, specifically developed to evaluate the aesthetics and visual impact, as well as to study the aerodynamic behaviour of the concrete shells in a wind tunnel. The goals and constraints of the method are identified and a step-by-step guidelines presented, aiming to be used as a reference in future studies. The printed geometry is validated by high-resolution assessment achieved by photogrammetry. The results are compared with the geometry computed through geometric nonlinear finite-element-based analysis, and no significant differences are recorded. The method is revealed to be an important tool for automatic shape generation and building scale models of shells. The latter enables the performing of wind tunnel tests to obtain pressure coefficients, essential for structural analysis of this type of structures.

Studies on reducing the scale of a double focusing mass spectrometer

International Nuclear Information System (INIS)

Chambers, D.M.; Gregg, H.R.; Andresen, B.D.

1993-05-01

Several groups have developed miniaturized sector mass spectrometers with the goal of remote sensing in confined spaces or portability. However, these achievements have been overshadowed by more successful development of man-portable quadrupole and ion trap mass spectrometers. Despite these accomplishments the development of a reduced-scale sector mass spectrometer remains attractive as a potentially low-cost, robust instrument requiring very simple electronics and low power. Previous studies on miniaturizing sector instruments include the use of a Mattauch-Herzog design for a portable mass spectrograph weighing less than 10 kg. Other work has included the use of a Nier-Johnson design in spacecraft-mountable gas chromatography mass spectrometers for the Viking spacecraft as well as miniature sector-based MS/MS instrument. Although theory for designing an optimized system with high resolution and mass accuracy is well understood, such specifications have not yet been achieved in a miniaturized instrument. To proceed further toward the development of a miniaturized sector mass spectrometer, experiments were conducted to understand and optimize a practical, yet nonideal instrument configuration. The sector mass spectrometer studied in this work is similar to the ones developed for the Viking project, but was further modified to be low cost, simple and robust. Characteristics of this instrument that highlight its simplicity include the use of a modified Varian leak detector ion source, source ion optics that use one extraction voltage, and an unshunted fixed nonhomogeneous magnetic sector. The effects of these design simplifications on ion trajectory were studied by manipulating the ion beam along with the magnetic sector position. This latter feature served as an aid to study ion focusing amidst fringing fields as well as nonhomogeneous forces and permitted empirical realignment of the instrument

Energy savings by reduced mixing in aeration tanks: results from a full scale investigation and long term implementation at Avedoere wastewater treatment plant.

Science.gov (United States)

Sharma, A K; Guildal, T; Thomsen, H R; Jacobsen, B N

2011-01-01

The aim of this project was to investigate the potential of reducing number of mixers in the biological treatment process and thereby achieve energy and economical savings and contribute to cleaner environment. The project was carried out at Avedoere wastewater treatment plant and a full scale investigation was conducted to study the effect of reduced mixing on flow velocity, suspended solid sedimentation, concentration gradients of oxygen and SS with depth and treatment efficiency. The only negative effect observed was on flow velocity; however the velocity was above the critical velocity. The plant has been operating with 50% of its designed number of mixers since September 2007 and long term results also confirm that reduced mixing did not have any negative effect on treatment efficiency. The estimated yearly electricity saving is 0.75 GWh/year.

Crossing Science-Policy-Societal Boundaries to Reduce Scientific and Institutional Uncertainty in Small-Scale Fisheries

Science.gov (United States)

Sutton, Abigail M.; Rudd, Murray A.

2016-10-01

The governance of small-scale fisheries (SSF) is challenging due to the uncertainty, complexity, and interconnectedness of social, political, ecological, and economical processes. Conventional SSF management has focused on a centralized and top-down approach. A major criticism of conventional management is the over-reliance on `expert science' to guide decision-making and poor consideration of fishers' contextually rich knowledge. That is thought to exacerbate the already low governance potential of SSF. Integrating scientific knowledge with fishers' knowledge is increasingly popular and is often assumed to help reduce levels of biophysical and institutional uncertainties. Many projects aimed at encouraging knowledge integration have, however, been unsuccessful. Our objective in this research was to assess factors that influence knowledge integration and the uptake of integrated knowledge into policy-making. We report results from 54 semi-structured interviews with SSF researchers and practitioners from around the globe. Our analysis is framed in terms of scientific credibility, societal legitimacy, and policy saliency, and we discuss cases that have been partially or fully successful in reducing uncertainty via push-and-pull-oriented boundary crossing initiatives. Our findings suggest that two important factors affect the science-policy-societal boundary: a lack of consensus among stakeholders about what constitutes credible knowledge and institutional uncertainty resulting from shifting policies and leadership change. A lack of training for scientific leaders and an apparent `shelf-life' for community organizations highlight the importance of ongoing institutional support for knowledge integration projects. Institutional support may be enhanced through such investments, such as capacity building and specialized platforms for knowledge integration.

Crossing Science-Policy-Societal Boundaries to Reduce Scientific and Institutional Uncertainty in Small-Scale Fisheries.

Science.gov (United States)

Sutton, Abigail M; Rudd, Murray A

2016-10-01

The governance of small-scale fisheries (SSF) is challenging due to the uncertainty, complexity, and interconnectedness of social, political, ecological, and economical processes. Conventional SSF management has focused on a centralized and top-down approach. A major criticism of conventional management is the over-reliance on 'expert science' to guide decision-making and poor consideration of fishers' contextually rich knowledge. That is thought to exacerbate the already low governance potential of SSF. Integrating scientific knowledge with fishers' knowledge is increasingly popular and is often assumed to help reduce levels of biophysical and institutional uncertainties. Many projects aimed at encouraging knowledge integration have, however, been unsuccessful. Our objective in this research was to assess factors that influence knowledge integration and the uptake of integrated knowledge into policy-making. We report results from 54 semi-structured interviews with SSF researchers and practitioners from around the globe. Our analysis is framed in terms of scientific credibility, societal legitimacy, and policy saliency, and we discuss cases that have been partially or fully successful in reducing uncertainty via push-and-pull-oriented boundary crossing initiatives. Our findings suggest that two important factors affect the science-policy-societal boundary: a lack of consensus among stakeholders about what constitutes credible knowledge and institutional uncertainty resulting from shifting policies and leadership change. A lack of training for scientific leaders and an apparent 'shelf-life' for community organizations highlight the importance of ongoing institutional support for knowledge integration projects. Institutional support may be enhanced through such investments, such as capacity building and specialized platforms for knowledge integration.

Modal behavior of a reduced scale pump-turbine impeller. Part 1: Experiments

International Nuclear Information System (INIS)

Escaler, X; Huetter, J K; Egusquiza, E; Farhat, M; Avellan, F

2010-01-01

An experimental investigation has been carried out to quantify the effects of surrounding fluid on the modal behavior of a reduced scale pump-turbine impeller. The modal properties of the fluid-structure system have been obtained by Experimental Modal Analysis (EMA) with the impeller suspended in air and inside a water reservoir. The impeller has been excited with an instrumented hammer and the response has been measured by means of miniature accelerometers. The Frequency Response Functions (FRF's) have been obtained from a large number of impacting positions in order to ensure the identification of the main mode shapes. As a result, the main modes of vibration have been well characterized both in air and in water in terms of natural frequency, damping ratio and mode shape. The first mode is the 2 Nodal Diameter (ND), the second one is the 0ND and the following ones are the 3ND coupled with the 1ND. The visual observation of the animated mode shapes and the level of the Modal Assurance Criterion (MAC) have permitted to correlate the homologous modes of vibration of the fluid-structure system in air and in water. From this comparison the added mass effect on the natural frequencies and the fluid effect on the damping ratios have been quantified for the most significant modes. With the surrounding water, the natural frequencies decrease in average by 10%. On the other hand, the damping ratios increase in average by 0.5%. In any case, the damping ratio appears to decrease with the frequency value of the mode.

(99)Tc(VII) Retardation, Reduction, and Redox Rate Scaling in Naturally Reduced Sediments.

Science.gov (United States)

Liu, Yuanyuan; Liu, Chongxuan; Kukkadapu, Ravi K; McKinley, James P; Zachara, John; Plymale, Andrew E; Miller, Micah D; Varga, Tamas; Resch, Charles T

2015-11-17

An experimental and modeling study was conducted to investigate pertechnetate (Tc(VII)O4(-)) retardation, reduction, and rate scaling in three sediments from Ringold formation at U.S. Department of Energy's Hanford site, where (99)Tc is a major contaminant in groundwater. Tc(VII) was reduced in all the sediments in both batch reactors and diffusion columns, with a faster rate in a sediment containing a higher concentration of HCl-extractable Fe(II). Tc(VII) migration in the diffusion columns was reductively retarded with retardation degrees correlated with Tc(VII) reduction rates. The reduction rates were faster in the diffusion columns than those in the batch reactors, apparently influenced by the spatial distribution of redox-reactive minerals along transport paths that supplied Tc(VII). X-ray computed tomography and autoradiography were performed to identify the spatial locations of Tc(VII) reduction and transport paths in the sediments, and results generally confirmed the newly found behavior of reaction rate changes from batch to column. The results from this study implied that Tc(VII) migration can be reductively retarded at Hanford site with a retardation degree dependent on reactive Fe(II) content and its distribution in sediments. This study also demonstrated that an effective reaction rate may be faster in transport systems than that in well-mixed reactors.

Experimental evaluation of a self-powered smart damping system in reducing vibrations of a full-scale stay cable

International Nuclear Information System (INIS)

Kim, In-Ho; Jung, Hyung-Jo; Koo, Jeong-Hoi

2010-01-01

This paper investigates the effectiveness of a self-powered smart damping system consisting of a magnetorheological (MR) damper and an electromagnetic induction (EMI) device in reducing cable vibrations. The proposed smart damping system incorporates an EMI device, which is capable of converting vibration energy into useful electrical energy. Thus, the incorporated EMI device can be used as an alternative power source for the MR damper, making it a self-powering system. The primary goal of this experimental study is to evaluate the performance of the proposed smart damping system using a full-scale, 44.7 m long, high-tension cable. To this end, an EMI part and an MR damper were designed and manufactured. Using a cable test setup in a laboratory setting, a series of tests were performed to evaluate the effectiveness of the self-powered smart damping system in reducing free vibration responses of the cable. The performances of the proposed smart damping system are compared with those of an equivalent passive system. Moreover, the damping characteristics of the smart damping system and the passive system are compared. The experimental results show that the self-powered smart damping system outperforms the passive control cases in reducing the vibrations of the cable. The results also show that the EMI can operate the smart damping system as a sole power source, demonstrating the feasibility of the self-powering capability of the system

Lack of cross-scale linkages reduces robustness of community-based fisheries management.

Directory of Open Access Journals (Sweden)

Richard Cudney-Bueno

Full Text Available Community-based management and the establishment of marine reserves have been advocated worldwide as means to overcome overexploitation of fisheries. Yet, researchers and managers are divided regarding the effectiveness of these measures. The "tragedy of the commons" model is often accepted as a universal paradigm, which assumes that unless managed by the State or privatized, common-pool resources are inevitably overexploited due to conflicts between the self-interest of individuals and the goals of a group as a whole. Under this paradigm, the emergence and maintenance of effective community-based efforts that include cooperative risky decisions as the establishment of marine reserves could not occur. In this paper, we question these assumptions and show that outcomes of commons dilemmas can be complex and scale-dependent. We studied the evolution and effectiveness of a community-based management effort to establish, monitor, and enforce a marine reserve network in the Gulf of California, Mexico. Our findings build on social and ecological research before (1997-2001, during (2002 and after (2003-2004 the establishment of marine reserves, which included participant observation in >100 fishing trips and meetings, interviews, as well as fishery dependent and independent monitoring. We found that locally crafted and enforced harvesting rules led to a rapid increase in resource abundance. Nevertheless, news about this increase spread quickly at a regional scale, resulting in poaching from outsiders and a subsequent rapid cascading effect on fishing resources and locally-designed rule compliance. We show that cooperation for management of common-pool fisheries, in which marine reserves form a core component of the system, can emerge, evolve rapidly, and be effective at a local scale even in recently organized fisheries. Stakeholder participation in monitoring, where there is a rapid feedback of the systems response, can play a key role in reinforcing

WebPIE : A web-scale parallel inference engine using MapReduce

NARCIS (Netherlands)

Urbani, Jacopo; Kotoulas, Spyros; Maassen, Jason; Van Harmelen, Frank; Bal, Henri

2012-01-01

The large amount of Semantic Web data and its fast growth pose a significant computational challenge in performing efficient and scalable reasoning. On a large scale, the resources of single machines are no longer sufficient and we are required to distribute the process to improve performance. The

Invasive lionfish reduce native fish abundance on a regional scale

OpenAIRE

Ballew, Nicholas G.; Bacheler, Nathan M.; Kellison, G. Todd; Schueller, Amy M.

2016-01-01

Invasive lionfish pose an unprecedented threat to biodiversity and fisheries throughout Atlantic waters off of the southeastern United States, the Caribbean, and the Gulf of Mexico. Here, we employ a spatially replicated Before-After-Control-Impact analysis with temporal pairing to quantify for the first time the impact of the lionfish invasion on native fish abundance across a broad regional scale and over the entire duration of the lionfish invasion (1990?2014). Our results suggest that 1) ...

Rapid Large Scale Reprocessing of the ODI Archive using the QuickReduce Pipeline

Science.gov (United States)

Gopu, A.; Kotulla, R.; Young, M. D.; Hayashi, S.; Harbeck, D.; Liu, W.; Henschel, R.

2015-09-01

The traditional model of astronomers collecting their observations as raw instrument data is being increasingly replaced by astronomical observatories serving standard calibrated data products to observers and to the public at large once proprietary restrictions are lifted. For this model to be effective, observatories need the ability to periodically re-calibrate archival data products as improved master calibration products or pipeline improvements become available, and also to allow users to rapidly calibrate their data on-the-fly. Traditional astronomy pipelines are heavily I/O dependent and do not scale with increasing data volumes. In this paper, we present the One Degree Imager - Portal, Pipeline and Archive (ODI-PPA) calibration pipeline framework which integrates the efficient and parallelized QuickReduce pipeline to enable a large number of simultaneous, parallel data reduction jobs - initiated by operators AND/OR users - while also ensuring rapid processing times and full data provenance. Our integrated pipeline system allows re-processing of the entire ODI archive (˜15,000 raw science frames, ˜3.0 TB compressed) within ˜18 hours using twelve 32-core compute nodes on the Big Red II supercomputer. Our flexible, fast, easy to operate, and highly scalable framework improves access to ODI data, in particular when data rates double with an upgraded focal plane (scheduled for 2015), and also serve as a template for future data processing infrastructure across the astronomical community and beyond.

Reducing Mercury Pollution from Artisanal and Small-Scale Gold Mining

Science.gov (United States)

To reduce airborne mercury emissions from these Gold Shops, EPA and the Argonne National Laboratory (ANL) have partnered to design a low cost, easily constructible technology called the Gold Shop Mercury Capture System (MCS).

Scaling Techniques for Massive Scale-Free Graphs in Distributed (External) Memory

KAUST Repository

Pearce, Roger

2013-05-01

We present techniques to process large scale-free graphs in distributed memory. Our aim is to scale to trillions of edges, and our research is targeted at leadership class supercomputers and clusters with local non-volatile memory, e.g., NAND Flash. We apply an edge list partitioning technique, designed to accommodate high-degree vertices (hubs) that create scaling challenges when processing scale-free graphs. In addition to partitioning hubs, we use ghost vertices to represent the hubs to reduce communication hotspots. We present a scaling study with three important graph algorithms: Breadth-First Search (BFS), K-Core decomposition, and Triangle Counting. We also demonstrate scalability on BG/P Intrepid by comparing to best known Graph500 results. We show results on two clusters with local NVRAM storage that are capable of traversing trillion-edge scale-free graphs. By leveraging node-local NAND Flash, our approach can process thirty-two times larger datasets with only a 39% performance degradation in Traversed Edges Per Second (TEPS). © 2013 IEEE.

Evaluation of scaling concepts for integral system test facilities

International Nuclear Information System (INIS)

Condie, K.G.; Larson, T.K.; Davis, C.B.

1987-01-01

A study was conducted by EG and G Idaho, Inc., to identify and technically evaluate potential concepts which will allow the U.S. Nuclear Regulatory Commission to maintain the capability to conduct future integral, thermal-hydraulic facility experiments of interest to light water reactor safety. This paper summarizes the methodology used in the study and presents a rankings for each facility concept relative to its ability to simulate phenomena identified as important in selected reactor transients in Babcock and Wilcox and Westinghouse large pressurized water reactors. Established scaling methodologies are used to develop potential concepts for scaled integral thermal-hydraulic experiment facilities. Concepts selected included: full height, full pressure water; reduced height, reduced pressure water; reduced height, full pressure water; one-tenth linear, full pressure water; and reduced height, full scaled pressure Freon. Results from this study suggest that a facility capable of operating at typical reactor operating conditions will scale most phenomena reasonably well. Local heat transfer phenomena is best scaled by the full height facility, while the reduced height facilities provide better scaling where multi-dimensional phenomena are considered important. Although many phenomena in facilities using Freon or water at nontypical pressure will scale reasonably well, those phenomena which are heavily dependent on quality can be distorted. Furthermore, relation of data produced in facilities operating with nontypical fluids or at nontypical pressures to large plants will be a difficult and time-consuming process

A reduced-order modeling approach to represent subgrid-scale hydrological dynamics for land-surface simulations: application in a polygonal tundra landscape

Science.gov (United States)

Pau, G. S. H.; Bisht, G.; Riley, W. J.

2014-09-01

Existing land surface models (LSMs) describe physical and biological processes that occur over a wide range of spatial and temporal scales. For example, biogeochemical and hydrological processes responsible for carbon (CO2, CH4) exchanges with the atmosphere range from the molecular scale (pore-scale O2 consumption) to tens of kilometers (vegetation distribution, river networks). Additionally, many processes within LSMs are nonlinearly coupled (e.g., methane production and soil moisture dynamics), and therefore simple linear upscaling techniques can result in large prediction error. In this paper we applied a reduced-order modeling (ROM) technique known as "proper orthogonal decomposition mapping method" that reconstructs temporally resolved fine-resolution solutions based on coarse-resolution solutions. We developed four different methods and applied them to four study sites in a polygonal tundra landscape near Barrow, Alaska. Coupled surface-subsurface isothermal simulations were performed for summer months (June-September) at fine (0.25 m) and coarse (8 m) horizontal resolutions. We used simulation results from three summer seasons (1998-2000) to build ROMs of the 4-D soil moisture field for the study sites individually (single-site) and aggregated (multi-site). The results indicate that the ROM produced a significant computational speedup (> 103) with very small relative approximation error (training the ROM. We also demonstrate that our approach: (1) efficiently corrects for coarse-resolution model bias and (2) can be used for polygonal tundra sites not included in the training data set with relatively good accuracy (< 1.7% relative error), thereby allowing for the possibility of applying these ROMs across a much larger landscape. By coupling the ROMs constructed at different scales together hierarchically, this method has the potential to efficiently increase the resolution of land models for coupled climate simulations to spatial scales consistent with

Understanding Antipsychotic Drug Treatment Effects: A Novel Method to Reduce Pseudospecificity of the Positive and Negative Syndrome Scale (PANSS) Factors.

Science.gov (United States)

Hopkins, Seth C; Ogirala, Ajay; Loebel, Antony; Koblan, Kenneth S

2017-12-01

The Positive and Negative Syndrome Scale (PANSS) is the most widely used efficacy measure in acute treatment studies of schizophrenia. However, interpretation of the efficacy of antipsychotics in improving specific symptom domains is confounded by moderate-to-high correlations among standard (Marder) PANSS factors. The authors review the results of an uncorrelated PANSS score matrix (UPSM) transform designed to reduce pseudospecificity in assessment of symptom change in patients with schizophrenia. Based on a factor analysis of five pooled, placebo-controlled lurasidone clinical trials (N=1,710 patients), a UPSM transform was identified that generated PANSS factors with high face validity (good correlation with standard Marder PANSS factors), and high specificity/orthogonality (low levels of between-factor correlation measuring change during treatment). Between-factor correlations were low at baseline for both standard (Marder) PANSS factors and transformed PANSS factors. However, when measured change in symptom severity was measured during treatment (in a pooled 5-study analysis), there was a notable difference for standard PANSS factors, where changes across factors were found to be highly correlated (factors exhibited pseudospecificity), compared to transformed PANSS factors, where factor change scores exhibited the same low levels of between-factor correlation observed at baseline. At Week 6-endpoint, correlations among PANSS factor severity scores were moderate-to-high for standard factors (0.34-0.68), but continued to be low for the transformed factors (-0.22-0.20). As an additional validity check, we analyzed data from one of the original five pooled clinical trials that included other well-validated assessment scales (MADRS, Negative Symptom Assessment scale [NSA]). In this baseline analysis, UPSM-transformed PANSS factor severity scores (negative and depression factors) were found to correlate well with the MADRS and NSA. The availability of transformed

Hybrid reduced order modeling for assembly calculations

Energy Technology Data Exchange (ETDEWEB)

Bang, Youngsuk, E-mail: ysbang00@fnctech.com [FNC Technology, Co. Ltd., Yongin-si (Korea, Republic of); Abdel-Khalik, Hany S., E-mail: abdelkhalik@purdue.edu [Purdue University, West Lafayette, IN (United States); Jessee, Matthew A., E-mail: jesseema@ornl.gov [Oak Ridge National Laboratory, Oak Ridge, TN (United States); Mertyurek, Ugur, E-mail: mertyurek@ornl.gov [Oak Ridge National Laboratory, Oak Ridge, TN (United States)

2015-12-15

Highlights: • Reducing computational cost in engineering calculations. • Reduced order modeling algorithm for multi-physics problem like assembly calculation. • Non-intrusive algorithm with random sampling. • Pattern recognition in the components with high sensitive and large variation. - Abstract: While the accuracy of assembly calculations has considerably improved due to the increase in computer power enabling more refined description of the phase space and use of more sophisticated numerical algorithms, the computational cost continues to increase which limits the full utilization of their effectiveness for routine engineering analysis. Reduced order modeling is a mathematical vehicle that scales down the dimensionality of large-scale numerical problems to enable their repeated executions on small computing environment, often available to end users. This is done by capturing the most dominant underlying relationships between the model's inputs and outputs. Previous works demonstrated the use of the reduced order modeling for a single physics code, such as a radiation transport calculation. This manuscript extends those works to coupled code systems as currently employed in assembly calculations. Numerical tests are conducted using realistic SCALE assembly models with resonance self-shielding, neutron transport, and nuclides transmutation/depletion models representing the components of the coupled code system.

Hybrid reduced order modeling for assembly calculations

International Nuclear Information System (INIS)

Bang, Youngsuk; Abdel-Khalik, Hany S.; Jessee, Matthew A.; Mertyurek, Ugur

2015-01-01

Highlights: • Reducing computational cost in engineering calculations. • Reduced order modeling algorithm for multi-physics problem like assembly calculation. • Non-intrusive algorithm with random sampling. • Pattern recognition in the components with high sensitive and large variation. - Abstract: While the accuracy of assembly calculations has considerably improved due to the increase in computer power enabling more refined description of the phase space and use of more sophisticated numerical algorithms, the computational cost continues to increase which limits the full utilization of their effectiveness for routine engineering analysis. Reduced order modeling is a mathematical vehicle that scales down the dimensionality of large-scale numerical problems to enable their repeated executions on small computing environment, often available to end users. This is done by capturing the most dominant underlying relationships between the model's inputs and outputs. Previous works demonstrated the use of the reduced order modeling for a single physics code, such as a radiation transport calculation. This manuscript extends those works to coupled code systems as currently employed in assembly calculations. Numerical tests are conducted using realistic SCALE assembly models with resonance self-shielding, neutron transport, and nuclides transmutation/depletion models representing the components of the coupled code system.

Genome-scale comparison and constraint-based metabolic reconstruction of the facultative anaerobic Fe(III-reducer Rhodoferax ferrireducens

Directory of Open Access Journals (Sweden)

Daugherty Sean

2009-09-01

Full Text Available Abstract Background Rhodoferax ferrireducens is a metabolically versatile, Fe(III-reducing, subsurface microorganism that is likely to play an important role in the carbon and metal cycles in the subsurface. It also has the unique ability to convert sugars to electricity, oxidizing the sugars to carbon dioxide with quantitative electron transfer to graphite electrodes in microbial fuel cells. In order to expand our limited knowledge about R. ferrireducens, the complete genome sequence of this organism was further annotated and then the physiology of R. ferrireducens was investigated with a constraint-based, genome-scale in silico metabolic model and laboratory studies. Results The iterative modeling and experimental approach unveiled exciting, previously unknown physiological features, including an expanded range of substrates that support growth, such as cellobiose and citrate, and provided additional insights into important features such as the stoichiometry of the electron transport chain and the ability to grow via fumarate dismutation. Further analysis explained why R. ferrireducens is unable to grow via photosynthesis or fermentation of sugars like other members of this genus and uncovered novel genes for benzoate metabolism. The genome also revealed that R. ferrireducens is well-adapted for growth in the subsurface because it appears to be capable of dealing with a number of environmental insults, including heavy metals, aromatic compounds, nutrient limitation and oxidative stress. Conclusion This study demonstrates that combining genome-scale modeling with the annotation of a new genome sequence can guide experimental studies and accelerate the understanding of the physiology of under-studied yet environmentally relevant microorganisms.

Multi-Scale Modelling of Deformation and Fracture in a Biomimetic Apatite-Protein Composite: Molecular-Scale Processes Lead to Resilience at the μm-Scale.

Directory of Open Access Journals (Sweden)

Dirk Zahn

Full Text Available Fracture mechanisms of an enamel-like hydroxyapatite-collagen composite model are elaborated by means of molecular and coarse-grained dynamics simulation. Using fully atomistic models, we uncover molecular-scale plastic deformation and fracture processes initiated at the organic-inorganic interface. Furthermore, coarse-grained models are developed to investigate fracture patterns at the μm-scale. At the meso-scale, micro-fractures are shown to reduce local stress and thus prevent material failure after loading beyond the elastic limit. On the basis of our multi-scale simulation approach, we provide a molecular scale rationalization of this phenomenon, which seems key to the resilience of hierarchical biominerals, including teeth and bone.

Influence of biofilm formation on corrosion and scaling in geothermal plants

Science.gov (United States)

Kleyböcker, Anne; Lerm, Stephanie; Monika, Kasina; Tobias, Lienen; Florian, Eichinger; Andrea, Seibt; Markus, Wolfgramm; Hilke, Würdemann

2017-04-01

Process failures may occur due to corrosion and scaling processes in open loop geothermal systems. Especially after heat extraction, sulfate reducing bacteria (SRB) contribute to corrosion processes due to a more favorable temperature for their growth. In biofilms containing FeS scales, corrosion processes are enhanced. Furthermore, scales can lead to reduced pipe profiles, to a diminished heat transfer and a decrease in the wellbore injectivity. Inhibitors are frequently applied to minimize scaling in technical systems. A prerequisite for the application of inhibitors in geothermal plants located in the Molasse basin is their degradability under reservoir conditions, e. g. in a reduced environment. In order to determine the effects of scale-inhibitors on the subsurface and microbial processes, laboratory experiments were performed focusing on the microbial inhibitor degradation. First results indicate that the inhibitor degradation under anaerobic conditions is possible. Besides the inhibitor application also other techniques are investigated to economically reduce corrosion and scaling in geothermal plants. In a mobile bypass system, the influence of biofilm formation on corrosion and scaling was investigated. The bypass system was tested at a geothermal heat store in the North German Basin. The plant is operated with highly saline fluid (salinity 130 g/L) and known to be affected by SRB. The SRB contributed to corrosion damages especially at the pump in the well on the cold side. Heat shocks were successfully used in the bypass system to reduce biofilm formation as well as corrosion and scaling processes.

Generalized reduced MHD equations

International Nuclear Information System (INIS)

Kruger, S.E.; Hegna, C.C.; Callen, J.D.

1998-07-01

A new derivation of reduced magnetohydrodynamic (MHD) equations is presented. A multiple-time-scale expansion is employed. It has the advantage of clearly separating the three time scales of the problem associated with (1) MHD equilibrium, (2) fluctuations whose wave vector is aligned perpendicular to the magnetic field, and (3) those aligned parallel to the magnetic field. The derivation is carried out without relying on a large aspect ratio assumption; therefore this model can be applied to any general toroidal configuration. By accounting for the MHD equilibrium and constraints to eliminate the fast perpendicular waves, equations are derived to evolve scalar potential quantities on a time scale associated with the parallel wave vector (shear-alfven wave time scale), which is the time scale of interest for MHD instability studies. Careful attention is given in the derivation to satisfy energy conservation and to have manifestly divergence-free magnetic fields to all orders in the expansion parameter. Additionally, neoclassical closures and equilibrium shear flow effects are easily accounted for in this model. Equations for the inner resistive layer are derived which reproduce the linear ideal and resistive stability criterion of Glasser, Greene, and Johnson

Refining and validating the Social Interaction Anxiety Scale and the Social Phobia Scale.

Science.gov (United States)

Carleton, R Nicholas; Collimore, Kelsey C; Asmundson, Gordon J G; McCabe, Randi E; Rowa, Karen; Antony, Martin M

2009-01-01

The Social Interaction Anxiety Scale and Social Phobia Scale are companion measures for assessing symptoms of social anxiety and social phobia. The scales have good reliability and validity across several samples, however, exploratory and confirmatory factor analyses have yielded solutions comprising substantially different item content and factor structures. These discrepancies are likely the result of analyzing items from each scale separately or simultaneously. The current investigation sets out to assess items from those scales, both simultaneously and separately, using exploratory and confirmatory factor analyses in an effort to resolve the factor structure. Participants consisted of a clinical sample (n 5353; 54% women) and an undergraduate sample (n 5317; 75% women) who completed the Social Interaction Anxiety Scale and Social Phobia Scale, along with additional fear-related measures to assess convergent and discriminant validity. A three-factor solution with a reduced set of items was found to be most stable, irrespective of whether the items from each scale are assessed together or separately. Items from the Social Interaction Anxiety Scale represented one factor, whereas items from the Social Phobia Scale represented two other factors. Initial support for scale and factor validity, along with implications and recommendations for future research, is provided. (c) 2009 Wiley-Liss, Inc.

Multiple time scale methods in tokamak magnetohydrodynamics

International Nuclear Information System (INIS)

Jardin, S.C.

1984-01-01

Several methods are discussed for integrating the magnetohydrodynamic (MHD) equations in tokamak systems on other than the fastest time scale. The dynamical grid method for simulating ideal MHD instabilities utilizes a natural nonorthogonal time-dependent coordinate transformation based on the magnetic field lines. The coordinate transformation is chosen to be free of the fast time scale motion itself, and to yield a relatively simple scalar equation for the total pressure, P = p + B 2 /2μ 0 , which can be integrated implicitly to average over the fast time scale oscillations. Two methods are described for the resistive time scale. The zero-mass method uses a reduced set of two-fluid transport equations obtained by expanding in the inverse magnetic Reynolds number, and in the small ratio of perpendicular to parallel mobilities and thermal conductivities. The momentum equation becomes a constraint equation that forces the pressure and magnetic fields and currents to remain in force balance equilibrium as they evolve. The large mass method artificially scales up the ion mass and viscosity, thereby reducing the severe time scale disparity between wavelike and diffusionlike phenomena, but not changing the resistive time scale behavior. Other methods addressing the intermediate time scales are discussed

Useful scaling parameters for the pulse tube

International Nuclear Information System (INIS)

Lee, J.M.; Kittel, P.; Timmerhaus, K.D.

1996-01-01

A set of dimensionless scaling parameters for use in correlating performance data for Pulse Tube Refrigerators is presented. The dimensionless groups result after scaling the mass and energy conservation equations, and the equation of motion for an axisymmetric, two-dimensional ideal gas system. Allowed are viscous effects and conduction heat transfer between the gas and the tube wall. The scaling procedure results in reducing the original 23 dimensional variables to a set of 11 dimensionless scaling groups. Dimensional analysis is used to verify that the 11 dimensionless groups obtained is the minimum number needed to describe the system. The authors also examine 6 limiting cases which progressively reduce the number of dimensionless groups from 11 to 3. The physical interpretation of the parameters are described, and their usefulness is outlined for understanding how heat transfer and mass streaming affect ideal enthalpy flow

Understanding scaling laws

International Nuclear Information System (INIS)

Lysenko, W.P.

1986-01-01

Accelerator scaling laws how they can be generated, and how they are used are discussed. A scaling law is a relation between machine parameters and beam parameters. An alternative point of view is that a scaling law is an imposed relation between the equations of motion and the initial conditions. The relation between the parameters is obtained by requiring the beam to be matched. (A beam is said to be matched if the phase-space distribution function is a function of single-particle invariants of the motion.) Because of this restriction, the number of independent parameters describing the system is reduced. Using simple models for bunched- and unbunched-beam situations. Scaling laws are shown to determine the general behavior of beams in accelerators. Such knowledge is useful in design studies for new machines such as high-brightness linacs. The simple model presented shows much of the same behavior as a more detailed RFQ model

Energy spectrum, dissipation, and spatial structures in reduced Hall magnetohydrodynamic

Energy Technology Data Exchange (ETDEWEB)

Martin, L. N.; Dmitruk, P. [Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and IFIBA, CONICET, Ciudad Universitaria, 1428 Buenos Aires (Argentina); Gomez, D. O. [Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and IFIBA, CONICET, Ciudad Universitaria, 1428 Buenos Aires (Argentina); Instituto de Astronomia y Fisica del Espacio, CONICET, Buenos Aires (Argentina)

2012-05-15

We analyze the effect of the Hall term in the magnetohydrodynamic turbulence under a strong externally supported magnetic field, seeing how this changes the energy cascade, the characteristic scales of the flow, and the dynamics of global magnitudes, with particular interest in the dissipation. Numerical simulations of freely evolving three-dimensional reduced magnetohydrodynamics are performed, for different values of the Hall parameter (the ratio of the ion skin depth to the macroscopic scale of the turbulence) controlling the impact of the Hall term. The Hall effect modifies the transfer of energy across scales, slowing down the transfer of energy from the large scales up to the Hall scale (ion skin depth) and carrying faster the energy from the Hall scale to smaller scales. The final outcome is an effective shift of the dissipation scale to larger scales but also a development of smaller scales. Current sheets (fundamental structures for energy dissipation) are affected in two ways by increasing the Hall effect, with a widening but at the same time generating an internal structure within them. In the case where the Hall term is sufficiently intense, the current sheet is fully delocalized. The effect appears to reduce impulsive effects in the flow, making it less intermittent.

Scaling laws for modeling nuclear reactor systems

International Nuclear Information System (INIS)

Nahavandi, A.N.; Castellana, F.S.; Moradkhanian, E.N.

1979-01-01

Scale models are used to predict the behavior of nuclear reactor systems during normal and abnormal operation as well as under accident conditions. Three types of scaling procedures are considered: time-reducing, time-preserving volumetric, and time-preserving idealized model/prototype. The necessary relations between the model and the full-scale unit are developed for each scaling type. Based on these relationships, it is shown that scaling procedures can lead to distortion in certain areas that are discussed. It is advised that, depending on the specific unit to be scaled, a suitable procedure be chosen to minimize model-prototype distortion

Using proteomic data to assess a genome-scale "in silico" model of metal reducing bacteria in the simulation of field-scale uranium bioremediation

Science.gov (United States)

Yabusaki, S.; Fang, Y.; Wilkins, M. J.; Long, P.; Rifle IFRC Science Team

2011-12-01

A series of field experiments in a shallow alluvial aquifer at a former uranium mill tailings site have demonstrated that indigenous bacteria can be stimulated with acetate to catalyze the conversion of hexavalent uranium in a groundwater plume to immobile solid-associated uranium in the +4 oxidation state. While this bioreduction of uranium has been shown to lower groundwater concentrations below actionable standards, a viable remediation methodology will need a mechanistic, predictive and quantitative understanding of the microbially-mediated reactions that catalyze the reduction of uranium in the context of site-specific processes, properties, and conditions. At the Rifle IFRC site, we are investigating the impacts on uranium behavior of pulsed acetate amendment, acetate-oxidizing iron and sulfate reducing bacteria, seasonal water table variation, spatially-variable physical (hydraulic conductivity, porosity) and geochemical (reactive surface area) material properties. The simulation of three-dimensional, variably saturated flow and biogeochemical reactive transport during a uranium bioremediation field experiment includes a genome-scale in silico model of Geobacter sp. to represent the Fe(III) terminal electron accepting process (TEAP). The Geobacter in silico model of cell-scale physiological metabolic pathways is comprised of hundreds of intra-cellular and environmental exchange reactions. One advantage of this approach is that the TEAP reaction stoichiometry and rate are now functions of the metabolic status of the microorganism. The linkage of in silico model reactions to specific Geobacter proteins has enabled the use of groundwater proteomic analyses to assess the accuracy of the model under evolving hydrologic and biogeochemical conditions. In this case, the largest predicted fluxes through in silico model reactions generally correspond to high abundances of proteins linked to those reactions (e.g. the condensation reaction catalyzed by the protein

Appraising options to reduce shallow groundwater tables and enhance flow conditions over regional scales in an irrigated alluvial aquifer system

Science.gov (United States)

Morway, Eric D.; Gates, Timothy K.; Niswonger, Richard G.

2013-01-01

Some of the world’s key agricultural production systems face big challenges to both water quantity and quality due to shallow groundwater that results from long-term intensive irrigation, namely waterlogging and salinity, water losses, and environmental problems. This paper focuses on water quantity issues, presenting finite-difference groundwater models developed to describe shallow water table levels, non-beneficial groundwater consumptive use, and return flows to streams across two regions within an irrigated alluvial river valley in southeastern Colorado, USA. The models are calibrated and applied to simulate current baseline conditions in the alluvial aquifer system and to examine actions for potentially improving these conditions. The models provide a detailed description of regional-scale subsurface unsaturated and saturated flow processes, thereby enabling detailed spatiotemporal description of groundwater levels, recharge to infiltration ratios, partitioning of ET originating from the unsaturated and saturated zones, and groundwater flows, among other variables. Hybrid automated and manual calibration of the models is achieved using extensive observations of groundwater hydraulic head, groundwater return flow to streams, aquifer stratigraphy, canal seepage, total evapotranspiration, the portion of evapotranspiration supplied by upflux from the shallow water table, and irrigation flows. Baseline results from the two regional-scale models are compared to model predictions under variations of four alternative management schemes: (1) reduced seepage from earthen canals, (2) reduced irrigation applications, (3) rotational lease fallowing (irrigation water leased to municipalities, resulting in temporary dry-up of fields), and (4) combinations of these. The potential for increasing the average water table depth by up to 1.1 and 0.7 m in the two respective modeled regions, thereby reducing the threat of waterlogging and lowering non-beneficial consumptive use

Hybrid reduced order modeling for assembly calculations

Energy Technology Data Exchange (ETDEWEB)

Bang, Y.; Abdel-Khalik, H. S. [North Carolina State University, Raleigh, NC (United States); Jessee, M. A.; Mertyurek, U. [Oak Ridge National Laboratory, Oak Ridge, TN (United States)

2013-07-01

While the accuracy of assembly calculations has considerably improved due to the increase in computer power enabling more refined description of the phase space and use of more sophisticated numerical algorithms, the computational cost continues to increase which limits the full utilization of their effectiveness for routine engineering analysis. Reduced order modeling is a mathematical vehicle that scales down the dimensionality of large-scale numerical problems to enable their repeated executions on small computing environment, often available to end users. This is done by capturing the most dominant underlying relationships between the model's inputs and outputs. Previous works demonstrated the use of the reduced order modeling for a single physics code, such as a radiation transport calculation. This manuscript extends those works to coupled code systems as currently employed in assembly calculations. Numerical tests are conducted using realistic SCALE assembly models with resonance self-shielding, neutron transport, and nuclides transmutation/depletion models representing the components of the coupled code system. (authors)

Sparse maps—A systematic infrastructure for reduced-scaling electronic structure methods. I. An efficient and simple linear scaling local MP2 method that uses an intermediate basis of pair natural orbitals

Energy Technology Data Exchange (ETDEWEB)

Pinski, Peter; Riplinger, Christoph; Neese, Frank, E-mail: evaleev@vt.edu, E-mail: frank.neese@cec.mpg.de [Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, D-45470 Mülheim an der Ruhr (Germany); Valeev, Edward F., E-mail: evaleev@vt.edu, E-mail: frank.neese@cec.mpg.de [Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24061 (United States)

2015-07-21

In this work, a systematic infrastructure is described that formalizes concepts implicit in previous work and greatly simplifies computer implementation of reduced-scaling electronic structure methods. The key concept is sparse representation of tensors using chains of sparse maps between two index sets. Sparse map representation can be viewed as a generalization of compressed sparse row, a common representation of a sparse matrix, to tensor data. By combining few elementary operations on sparse maps (inversion, chaining, intersection, etc.), complex algorithms can be developed, illustrated here by a linear-scaling transformation of three-center Coulomb integrals based on our compact code library that implements sparse maps and operations on them. The sparsity of the three-center integrals arises from spatial locality of the basis functions and domain density fitting approximation. A novel feature of our approach is the use of differential overlap integrals computed in linear-scaling fashion for screening products of basis functions. Finally, a robust linear scaling domain based local pair natural orbital second-order Möller-Plesset (DLPNO-MP2) method is described based on the sparse map infrastructure that only depends on a minimal number of cutoff parameters that can be systematically tightened to approach 100% of the canonical MP2 correlation energy. With default truncation thresholds, DLPNO-MP2 recovers more than 99.9% of the canonical resolution of the identity MP2 (RI-MP2) energy while still showing a very early crossover with respect to the computational effort. Based on extensive benchmark calculations, relative energies are reproduced with an error of typically <0.2 kcal/mol. The efficiency of the local MP2 (LMP2) method can be drastically improved by carrying out the LMP2 iterations in a basis of pair natural orbitals. While the present work focuses on local electron correlation, it is of much broader applicability to computation with sparse tensors in

Reducing work disability in Ankylosing Spondylitis – development of a work instability scale for AS

Directory of Open Access Journals (Sweden)

Helliwell Philip

2009-06-01

Full Text Available Abstract Background The Work Instability Scale for Rheumatoid Arthritis (RA-WIS is established and is used by physicians to identify patients at risk of job loss for rapid intervention. The study objective was to explore the concept of Work Instability (a mismatch between an individual's abilities and job demands in Ankylosing Spondylitis (AS and develop a Work Instability Scale specific to this population. Methods New items generated from qualitative interviews were combined with items from the RA-WIS to form a draft AS-WIS. Rasch analysis was used to examine the scaling properties of the AS-WIS using data generated through a postal survey. The scale was validated against a gold standard of expert assessment, a test-retest survey examined reliability. Results Fifty-seven participants who were in work returned the postal survey. Of the original 55 items 38 were shown to fit the Rasch model (χ2 37.5; df 38; p 0.494 and free of bias for gender and disease duration. Following analysis for discrimination against the gold standard assessments 20 items remained with good fit to the model (χ2 24.8; df 20; p 0.21. Test-retest reliability was 0.94. Conclusion The AS-WIS is a self-administered scale which meets the stringent requirements of modern measurement. Used as a screening tool it can identify those experiencing a mismatch at work who are at risk of job retention problems and work disability. Work instability is emerging as an important indication for the use of biologics, thus the AS-WIS has the potential to become an important outcome measure.

Reducing surface water pollution through the assessment of the cost-effectiveness of BMPs at different spatial scales.

Science.gov (United States)

Panagopoulos, Y; Makropoulos, C; Mimikou, M

2011-10-01

Two kinds of agricultural Best Management Practices (BMPs) were examined with respect to cost-effectiveness (CE) in reducing sediment, nitrates-nitrogen (NO(3)-N) and total phosphorus (TP) losses to surface waters of the Arachtos catchment in Western Greece. The establishment of filter strips at the edge of fields and a non-structural measure, namely fertilization reduction in alfalfa, combined with contour farming and zero-tillage in corn and reduction of animal numbers in pastureland, were evaluated. The Soil and Water Assessment Tool (SWAT) model was used as the non-point-source (NPS) estimator, while a simple economic component was developed estimating BMP implementation cost as the mean annual expenses needed to undertake and operate the practice for a 5-year period. After each BMP implementation, the ratio of their CE in reducing pollution was calculated for each Hydrologic Response Unit (HRU) separately, for each agricultural land use type entirely and for the whole catchment. The results at the HRU scale are presented comprehensively on a map, demonstrating the spatial differentiation of CE ratios across the catchment that enhances the identification of locations where each BMP is most advisable for implementation. Based on the analysis, a catchment management solution of affordable total cost would include the expensive measure of filter strips in corn and only in a small number of pastureland fields, in combination with the profitable measure of reducing fertilization to alfalfa fields. When examined for its impact on river loads at the outlet, the latter measure led to a 20 tn or 8% annual decrease of TP from the baseline with savings of 15€/kg of pollutant reduction. Filter strips in corn fields reduced annual sediments by 66 Ktn or 5%, NO(3)-N by 71 tn or 9.5% and TP by 27 tn or 10%, with an additional cost of 3.1 €/tn, 3.3 €/kg and 8.1 €/kg of each pollutant respectively. The study concludes that considerable reductions of several

Improving the Performance of the Extreme-scale Simulator

Energy Technology Data Exchange (ETDEWEB)

Engelmann, Christian [ORNL; Naughton III, Thomas J [ORNL

2014-01-01

Investigating the performance of parallel applications at scale on future high-performance computing (HPC) architectures and the performance impact of different architecture choices is an important component of HPC hardware/software co-design. The Extreme-scale Simulator (xSim) is a simulation-based toolkit for investigating the performance of parallel applications at scale. xSim scales to millions of simulated Message Passing Interface (MPI) processes. The overhead introduced by a simulation tool is an important performance and productivity aspect. This paper documents two improvements to xSim: (1) a new deadlock resolution protocol to reduce the parallel discrete event simulation management overhead and (2) a new simulated MPI message matching algorithm to reduce the oversubscription management overhead. The results clearly show a significant performance improvement, such as by reducing the simulation overhead for running the NAS Parallel Benchmark suite inside the simulator from 1,020\\% to 238% for the conjugate gradient (CG) benchmark and from 102% to 0% for the embarrassingly parallel (EP) and benchmark, as well as, from 37,511% to 13,808% for CG and from 3,332% to 204% for EP with accurate process failure simulation.

Test on large-scale seismic isolation elements

International Nuclear Information System (INIS)

Mazda, T.; Shiojiri, H.; Oka, Y.; Fujita, T.; Seki, M.

1989-01-01

Demonstration test of seismic isolation elements is considered as one of the most important items in the application of seismic isolation system to fast breeder reactor (FBR) plant. Facilities for testing seismic isolation elements have been built. This paper reports on tests for fullscale laminated rubber bearing and reduced scale models are conducted. From the result of the tests, the laminated rubber bearings turn out to satisfy the specification. Their basic characteristics are confirmed from the tests with fullscale and reduced scale models. The ultimate capacity of the bearings under the condition of ordinary temperature are evaluated

Predicting the effectiveness of different mulching techniques in reducing post-fire runoff and erosion at plot scale with the RUSLE, MMF and PESERA models.

Science.gov (United States)

Vieira, D C S; Serpa, D; Nunes, J P C; Prats, S A; Neves, R; Keizer, J J

2018-08-01

Wildfires have become a recurrent threat for many Mediterranean forest ecosystems. The characteristics of the Mediterranean climate, with its warm and dry summers and mild and wet winters, make this a region prone to wildfire occurrence as well as to post-fire soil erosion. This threat is expected to be aggravated in the future due to climate change and land management practices and planning. The wide recognition of wildfires as a driver for runoff and erosion in burnt forest areas has created a strong demand for model-based tools for predicting the post-fire hydrological and erosion response and, in particular, for predicting the effectiveness of post-fire management operations to mitigate these responses. In this study, the effectiveness of two post-fire treatments (hydromulch and natural pine needle mulch) in reducing post-fire runoff and soil erosion was evaluated against control conditions (i.e. untreated conditions), at different spatial scales. The main objective of this study was to use field data to evaluate the ability of different erosion models: (i) empirical (RUSLE), (ii) semi-empirical (MMF), and (iii) physically-based (PESERA), to predict the hydrological and erosive response as well as the effectiveness of different mulching techniques in fire-affected areas. The results of this study showed that all three models were reasonably able to reproduce the hydrological and erosive processes occurring in burned forest areas. In addition, it was demonstrated that the models can be calibrated at a small spatial scale (0.5 m 2 ) but provide accurate results at greater spatial scales (10 m 2 ). From this work, the RUSLE model seems to be ideal for fast and simple applications (i.e. prioritization of areas-at-risk) mainly due to its simplicity and reduced data requirements. On the other hand, the more complex MMF and PESERA models would be valuable as a base of a possible tool for assessing the risk of water contamination in fire-affected water bodies and

Meteorological Data Analysis Using MapReduce

Directory of Open Access Journals (Sweden)

Wei Fang

2014-01-01

Full Text Available In the atmospheric science, the scale of meteorological data is massive and growing rapidly. K-means is a fast and available cluster algorithm which has been used in many fields. However, for the large-scale meteorological data, the traditional K-means algorithm is not capable enough to satisfy the actual application needs efficiently. This paper proposes an improved MK-means algorithm (MK-means based on MapReduce according to characteristics of large meteorological datasets. The experimental results show that MK-means has more computing ability and scalability.

Evaluating Active Interventions to Reduce Student Procrastination

OpenAIRE

Martin, Joshua Deckert

2015-01-01

Procrastination is a pervasive problem in education. In computer science, procrastination and lack of necessary time management skills to complete programming projects are viewed as primary causes of student attrition. The most effective techniques known to reduce procrastination are resource-intensive and do not scale well to large classrooms. In this thesis, we examine three course interventions designed to both reduce procrastination and be scalable for large classrooms. Reflective writ...

Neutral glycans from sandfish skin can reduce friction of polymers

Science.gov (United States)

Vihar, Boštjan; Hanisch, Franz Georg; Baumgartner, Werner

2016-01-01

The lizard Scincus scincus, also known as sandfish, can move through aeolian desert sand in a swimming-like manner. A prerequisite for this ability is a special integument, i.e. scales with a very low friction for sand and a high abrasion resistance. Glycans in the scales are causally related to the low friction. Here, we analysed the glycans and found that neutral glycans with five to nine mannose residues are important. If these glycans were covalently bound to acrylic polymers like poly(methyl methacrylate) or acrylic car coatings at a density of approximately one molecule per 4 nm², friction for and adhesion of sand particles could be reduced to levels close to those observed with sandfish scales. This was also found true, if the glycans were isolated from sources other than sandfish scales like plants such as almonds or mistletoe. We speculate that these neutral glycans act as low density spacers separating sand particles from the dense scales thereby reducing van der Waals forces. PMID:27030038

A climate-change adaptation framework to reduce continental-scale vulnerability across conservation reserves

Science.gov (United States)

D.R. Magness; J.M. Morton; F. Huettmann; F.S. Chapin; A.D. McGuire

2011-01-01

Rapid climate change, in conjunction with other anthropogenic drivers, has the potential to cause mass species extinction. To minimize this risk, conservation reserves need to be coordinated at multiple spatial scales because the climate envelopes of many species may shift rapidly across large geographic areas. In addition, novel species assemblages and ecological...

Scale covariant physics: a 'quantum deformation' of classical electrodynamics

International Nuclear Information System (INIS)

Knoll, Yehonatan; Yavneh, Irad

2010-01-01

We present a deformation of classical electrodynamics, continuously depending on a 'quantum parameter', featuring manifest gauge, Poincare and scale covariance. The theory, dubbed extended charge dynamics (ECD), associates a certain length scale with each charge which, due to scale covariance, is an attribute of a solution, not a parameter of the theory. When the EM field experienced by an ECD charge is slowly varying over that length scale, the dynamics of the charge reduces to classical dynamics, its emitted radiation reduces to the familiar Lienard-Wiechert potential and the above length scale is identified as the charge's Compton length. It is conjectured that quantum mechanics describes statistical aspects of ensembles of ECD solutions, much like classical thermodynamics describes statistical aspects of ensembles of classical solutions. A unique 'remote sensing' feature of ECD, supporting that conjecture, is presented, along with an explanation for the illusion of a photon within a classical treatment of the EM field. Finally, a novel conservation law associated with the scale covariance of ECD is derived, indicating that the scale of a solution may 'drift' with time at a constant rate, much like translation covariance implies a uniform drift of the (average) position.

Economy of scale still holds true

International Nuclear Information System (INIS)

Anon.

1985-01-01

The economic merits of larger generating units have been questioned and have become subject to doubt and controversy. A 1980 study by Sargent and Lundy concluded that economy of scale still held. But some of the basic factors and major assumptions used in that study have changed. An update of those results, which also looks at whether reduced load growth rates affect the study's conclusions, finds economy of scale still applies

Moth wing scales slightly increase the absorbance of bat echolocation calls.

Directory of Open Access Journals (Sweden)

Jinyao Zeng

Full Text Available Coevolutionary arms races between predators and prey can lead to a diverse range of foraging and defense strategies, such as countermeasures between nocturnal insects and echolocating bats. Here, we show how the fine structure of wing scales may help moths by slightly increasing sound absorbance at frequencies typically used in bat echolocation. Using four widespread species of moths and butterflies, we found that moth scales are composed of honeycomb-like hollows similar to sound-absorbing material, but these were absent from butterfly scales. Micro-reverberation chamber experiments revealed that moth wings were more absorbent at the frequencies emitted by many echolocating bats (40-60 kHz than butterfly wings. Furthermore, moth wings lost absorbance at these frequencies when scales were removed, which suggests that some moths have evolved stealth tactics to reduce their conspicuousness to echolocating bats. Although the benefits to moths are relatively small in terms of reducing their target strengths, scales may nonetheless confer survival advantages by reducing the detection distances of moths by bats by 5-6%.

Improving predictions of large scale soil carbon dynamics: Integration of fine-scale hydrological and biogeochemical processes, scaling, and benchmarking

Science.gov (United States)

Riley, W. J.; Dwivedi, D.; Ghimire, B.; Hoffman, F. M.; Pau, G. S. H.; Randerson, J. T.; Shen, C.; Tang, J.; Zhu, Q.

2015-12-01

Numerical model representations of decadal- to centennial-scale soil-carbon dynamics are a dominant cause of uncertainty in climate change predictions. Recent attempts by some Earth System Model (ESM) teams to integrate previously unrepresented soil processes (e.g., explicit microbial processes, abiotic interactions with mineral surfaces, vertical transport), poor performance of many ESM land models against large-scale and experimental manipulation observations, and complexities associated with spatial heterogeneity highlight the nascent nature of our community's ability to accurately predict future soil carbon dynamics. I will present recent work from our group to develop a modeling framework to integrate pore-, column-, watershed-, and global-scale soil process representations into an ESM (ACME), and apply the International Land Model Benchmarking (ILAMB) package for evaluation. At the column scale and across a wide range of sites, observed depth-resolved carbon stocks and their 14C derived turnover times can be explained by a model with explicit representation of two microbial populations, a simple representation of mineralogy, and vertical transport. Integrating soil and plant dynamics requires a 'process-scaling' approach, since all aspects of the multi-nutrient system cannot be explicitly resolved at ESM scales. I will show that one approach, the Equilibrium Chemistry Approximation, improves predictions of forest nitrogen and phosphorus experimental manipulations and leads to very different global soil carbon predictions. Translating model representations from the site- to ESM-scale requires a spatial scaling approach that either explicitly resolves the relevant processes, or more practically, accounts for fine-resolution dynamics at coarser scales. To that end, I will present recent watershed-scale modeling work that applies reduced order model methods to accurately scale fine-resolution soil carbon dynamics to coarse-resolution simulations. Finally, we

Selective visual scaling of time-scale processes facilitates broadband learning of isometric force frequency tracking.

Science.gov (United States)

King, Adam C; Newell, Karl M

2015-10-01

The experiment investigated the effect of selectively augmenting faster time scales of visual feedback information on the learning and transfer of continuous isometric force tracking tasks to test the generality of the self-organization of 1/f properties of force output. Three experimental groups tracked an irregular target pattern either under a standard fixed gain condition or with selectively enhancement in the visual feedback display of intermediate (4-8 Hz) or high (8-12 Hz) frequency components of the force output. All groups reduced tracking error over practice, with the error lowest in the intermediate scaling condition followed by the high scaling and fixed gain conditions, respectively. Selective visual scaling induced persistent changes across the frequency spectrum, with the strongest effect in the intermediate scaling condition and positive transfer to novel feedback displays. The findings reveal an interdependence of the timescales in the learning and transfer of isometric force output frequency structures consistent with 1/f process models of the time scales of motor output variability.

MapReduce Based Parallel Neural Networks in Enabling Large Scale Machine Learning.

Science.gov (United States)

Liu, Yang; Yang, Jie; Huang, Yuan; Xu, Lixiong; Li, Siguang; Qi, Man

2015-01-01

Artificial neural networks (ANNs) have been widely used in pattern recognition and classification applications. However, ANNs are notably slow in computation especially when the size of data is large. Nowadays, big data has received a momentum from both industry and academia. To fulfill the potentials of ANNs for big data applications, the computation process must be speeded up. For this purpose, this paper parallelizes neural networks based on MapReduce, which has become a major computing model to facilitate data intensive applications. Three data intensive scenarios are considered in the parallelization process in terms of the volume of classification data, the size of the training data, and the number of neurons in the neural network. The performance of the parallelized neural networks is evaluated in an experimental MapReduce computer cluster from the aspects of accuracy in classification and efficiency in computation.

Active Learning of Classification Models with Likert-Scale Feedback.

Science.gov (United States)

Xue, Yanbing; Hauskrecht, Milos

2017-01-01

Annotation of classification data by humans can be a time-consuming and tedious process. Finding ways of reducing the annotation effort is critical for building the classification models in practice and for applying them to a variety of classification tasks. In this paper, we develop a new active learning framework that combines two strategies to reduce the annotation effort. First, it relies on label uncertainty information obtained from the human in terms of the Likert-scale feedback. Second, it uses active learning to annotate examples with the greatest expected change. We propose a Bayesian approach to calculate the expectation and an incremental SVM solver to reduce the time complexity of the solvers. We show the combination of our active learning strategy and the Likert-scale feedback can learn classification models more rapidly and with a smaller number of labeled instances than methods that rely on either Likert-scale labels or active learning alone.

Evaluation of a constipation risk assessment scale.

Science.gov (United States)

Zernike, W; Henderson, A

1999-06-01

This project was undertaken in order to evaluate the utility of a constipation risk assessment scale and the accompanying bowel management protocol. The risk assessment scale was primarily introduced to teach and guide staff in managing constipation when caring for patients. The intention of the project was to reduce the incidence of constipation in patients during their admission to hospital.

Column-Oriented Storage Techniques for MapReduce

OpenAIRE

Floratou, Avrilia; Patel, Jignesh; Shekita, Eugene; Tata, Sandeep

2011-01-01

Users of MapReduce often run into performance problems when they scale up their workloads. Many of the problems they encounter can be overcome by applying techniques learned from over three decades of research on parallel DBMSs. However, translating these techniques to a MapReduce implementation such as Hadoop presents unique challenges that can lead to new design choices. This paper describes how column-oriented storage techniques can be incorporated in Hadoop in a way that preserves its pop...

Reduced α-stable dynamics for multiple time scale systems forced with correlated additive and multiplicative Gaussian white noise

Science.gov (United States)

Thompson, William F.; Kuske, Rachel A.; Monahan, Adam H.

2017-11-01

Stochastic averaging problems with Gaussian forcing have been the subject of numerous studies, but far less attention has been paid to problems with infinite-variance stochastic forcing, such as an α-stable noise process. It has been shown that simple linear systems driven by correlated additive and multiplicative (CAM) Gaussian noise, which emerge in the context of reduced atmosphere and ocean dynamics, have infinite variance in certain parameter regimes. In this study, we consider the stochastic averaging of systems where a linear CAM noise process in the infinite variance parameter regime drives a comparatively slow process. We use (semi)-analytical approximations combined with numerical illustrations to compare the averaged process to one that is forced by a white α-stable process, demonstrating consistent properties in the case of large time-scale separation. We identify the conditions required for the fast linear CAM process to have such an influence in driving a slower process and then derive an (effectively) equivalent fast, infinite-variance process for which an existing stochastic averaging approximation is readily applied. The results are illustrated using numerical simulations of a set of example systems.

MapReduce Based Parallel Neural Networks in Enabling Large Scale Machine Learning

Directory of Open Access Journals (Sweden)

Yang Liu

2015-01-01

Full Text Available Artificial neural networks (ANNs have been widely used in pattern recognition and classification applications. However, ANNs are notably slow in computation especially when the size of data is large. Nowadays, big data has received a momentum from both industry and academia. To fulfill the potentials of ANNs for big data applications, the computation process must be speeded up. For this purpose, this paper parallelizes neural networks based on MapReduce, which has become a major computing model to facilitate data intensive applications. Three data intensive scenarios are considered in the parallelization process in terms of the volume of classification data, the size of the training data, and the number of neurons in the neural network. The performance of the parallelized neural networks is evaluated in an experimental MapReduce computer cluster from the aspects of accuracy in classification and efficiency in computation.

Goethite Bench-scale and Large-scale Preparation Tests

Energy Technology Data Exchange (ETDEWEB)

Josephson, Gary B.; Westsik, Joseph H.

2011-10-23

The Hanford Waste Treatment and Immobilization Plant (WTP) is the keystone for cleanup of high-level radioactive waste from our nation's nuclear defense program. The WTP will process high-level waste from the Hanford tanks and produce immobilized high-level waste glass for disposal at a national repository, low activity waste (LAW) glass, and liquid effluent from the vitrification off-gas scrubbers. The liquid effluent will be stabilized into a secondary waste form (e.g. grout-like material) and disposed on the Hanford site in the Integrated Disposal Facility (IDF) along with the low-activity waste glass. The major long-term environmental impact at Hanford results from technetium that volatilizes from the WTP melters and finally resides in the secondary waste. Laboratory studies have indicated that pertechnetate ({sup 99}TcO{sub 4}{sup -}) can be reduced and captured into a solid solution of {alpha}-FeOOH, goethite (Um 2010). Goethite is a stable mineral and can significantly retard the release of technetium to the environment from the IDF. The laboratory studies were conducted using reaction times of many days, which is typical of environmental subsurface reactions that were the genesis of this new process. This study was the first step in considering adaptation of the slow laboratory steps to a larger-scale and faster process that could be conducted either within the WTP or within the effluent treatment facility (ETF). Two levels of scale-up tests were conducted (25x and 400x). The largest scale-up produced slurries of Fe-rich precipitates that contained rhenium as a nonradioactive surrogate for {sup 99}Tc. The slurries were used in melter tests at Vitreous State Laboratory (VSL) to determine whether captured rhenium was less volatile in the vitrification process than rhenium in an unmodified feed. A critical step in the technetium immobilization process is to chemically reduce Tc(VII) in the pertechnetate (TcO{sub 4}{sup -}) to Tc(Iv)by reaction with the

Invariant relationships deriving from classical scaling transformations

International Nuclear Information System (INIS)

Bludman, Sidney; Kennedy, Dallas C.

2011-01-01

Because scaling symmetries of the Euler-Lagrange equations are generally not variational symmetries of the action, they do not lead to conservation laws. Instead, an extension of Noether's theorem reduces the equations of motion to evolutionary laws that prove useful, even if the transformations are not symmetries of the equations of motion. In the case of scaling, symmetry leads to a scaling evolutionary law, a first-order equation in terms of scale invariants, linearly relating kinematic and dynamic degrees of freedom. This scaling evolutionary law appears in dynamical and in static systems. Applied to dynamical central-force systems, the scaling evolutionary equation leads to generalized virial laws, which linearly connect the kinetic and potential energies. Applied to barotropic hydrostatic spheres, the scaling evolutionary equation linearly connects the gravitational and internal energy densities. This implies well-known properties of polytropes, describing degenerate stars and chemically homogeneous nondegenerate stellar cores.

Urban Stream Burial Increases Watershed-Scale Nitrate Export.

Directory of Open Access Journals (Sweden)

Jake J Beaulieu

Full Text Available Nitrogen (N uptake in streams is an important ecosystem service that reduces nutrient loading to downstream ecosystems. Here we synthesize studies that investigated the effects of urban stream burial on N-uptake in two metropolitan areas and use simulation modeling to scale our measurements to the broader watershed scale. We report that nitrate travels on average 18 times farther downstream in buried than in open streams before being removed from the water column, indicating that burial substantially reduces N uptake in streams. Simulation modeling suggests that as burial expands throughout a river network, N uptake rates increase in the remaining open reaches which somewhat offsets reduced N uptake in buried reaches. This is particularly true at low levels of stream burial. At higher levels of stream burial, however, open reaches become rare and cumulative N uptake across all open reaches in the watershed rapidly declines. As a result, watershed-scale N export increases slowly at low levels of stream burial, after which increases in export become more pronounced. Stream burial in the lower, more urbanized portions of the watershed had a greater effect on N export than an equivalent amount of stream burial in the upper watershed. We suggest that stream daylighting (i.e., uncovering buried streams can increase watershed-scale N retention.

Evaluating impacts of different longitudinal driver assistance systems on reducing multi-vehicle rear-end crashes during small-scale inclement weather.

Science.gov (United States)

Li, Ye; Xing, Lu; Wang, Wei; Wang, Hao; Dong, Changyin; Liu, Shanwen

2017-10-01

Multi-vehicle rear-end (MVRE) crashes during small-scale inclement (SSI) weather cause high fatality rates on freeways, which cannot be solved by traditional speed limit strategies. This study aimed to reduce MVRE crash risks during SSI weather using different longitudinal driver assistance systems (LDAS). The impact factors on MVRE crashes during SSI weather were firstly analyzed. Then, four LDAS, including Forward collision warning (FCW), Autonomous emergency braking (AEB), Adaptive cruise control (ACC) and Cooperative ACC (CACC), were modeled based on a unified platform, the Intelligent Driver Model (IDM). Simulation experiments were designed and a large number of simulations were then conducted to evaluate safety effects of different LDAS. Results indicate that the FCW and ACC system have poor performance on reducing MVRE crashes during SSI weather. The slight improvement of sight distance of FCW and the limitation of perception-reaction time of ACC lead the failure of avoiding MVRE crashes in most scenarios. The AEB system has the better effect due to automatic perception and reaction, as well as performing the full brake when encountering SSI weather. The CACC system has the best performance because wireless communication provides a larger sight distance and a shorter time delay at the sub-second level. Sensitivity analyses also indicated that the larger number of vehicles and speed changes after encountering SSI weather have negative impacts on safety performances. Results of this study provide useful information for accident prevention during SSI weather. Copyright © 2017 Elsevier Ltd. All rights reserved.

Generalized reduced magnetohydrodynamic equations

International Nuclear Information System (INIS)

Kruger, S.E.

1999-01-01

A new derivation of reduced magnetohydrodynamic (MHD) equations is presented. A multiple-time-scale expansion is employed. It has the advantage of clearly separating the three time scales of the problem associated with (1) MHD equilibrium, (2) fluctuations whose wave vector is aligned perpendicular to the magnetic field, and (3) those aligned parallel to the magnetic field. The derivation is carried out without relying on a large aspect ratio assumption; therefore this model can be applied to any general configuration. By accounting for the MHD equilibrium and constraints to eliminate the fast perpendicular waves, equations are derived to evolve scalar potential quantities on a time scale associated with the parallel wave vector (shear-Alfven wave time scale), which is the time scale of interest for MHD instability studies. Careful attention is given in the derivation to satisfy energy conservation and to have manifestly divergence-free magnetic fields to all orders in the expansion parameter. Additionally, neoclassical closures and equilibrium shear flow effects are easily accounted for in this model. Equations for the inner resistive layer are derived which reproduce the linear ideal and resistive stability criterion of Glasser, Greene, and Johnson. The equations have been programmed into a spectral initial value code and run with shear flow that is consistent with the equilibrium input into the code. Linear results of tearing modes with shear flow are presented which differentiate the effects of shear flow gradients in the layer with the effects of the shear flow decoupling multiple harmonics

ETLMR: A Highly Scalable Dimensional ETL Framework based on MapReduce

DEFF Research Database (Denmark)

Xiufeng, Liu; Thomsen, Christian; Pedersen, Torben Bach

2011-01-01

Extract-Transform-Load (ETL) flows periodically populate data warehouses (DWs) with data from different source systems. An increasing challenge for ETL fl ows is processing huge volumes of data quickly. MapReduce is establishing itself as the de-facto standard for large-scale data-intensive process......Extract-Transform-Load (ETL) flows periodically populate data warehouses (DWs) with data from different source systems. An increasing challenge for ETL fl ows is processing huge volumes of data quickly. MapReduce is establishing itself as the de-facto standard for large-scale data...

Reducing rotor weight

Energy Technology Data Exchange (ETDEWEB)

Cheney, M.C. [PS Enterprises, Inc., Glastonbury, CT (United States)

1997-12-31

The cost of energy for renewables has gained greater significance in recent years due to the drop in price in some competing energy sources, particularly natural gas. In pursuit of lower manufacturing costs for wind turbine systems, work was conducted to explore an innovative rotor designed to reduce weight and cost over conventional rotor systems. Trade-off studies were conducted to measure the influence of number of blades, stiffness, and manufacturing method on COE. The study showed that increasing number of blades at constant solidity significantly reduced rotor weight and that manufacturing the blades using pultrusion technology produced the lowest cost per pound. Under contracts with the National Renewable Energy Laboratory and the California Energy Commission, a 400 kW (33m diameter) turbine was designed employing this technology. The project included tests of an 80 kW (15.5m diameter) dynamically scaled rotor which demonstrated the viability of the design.

Reduced bispectrum seeded by helical primordial magnetic fields

Energy Technology Data Exchange (ETDEWEB)

Hortúa, Héctor Javier [Universidad Nacional de Colombia-Bogotá, Facultad de Ciencias, Departamento de Física, Carrera 30 Calle 45-03, C.P. 111321 Bogotá (Colombia); Castañeda, Leonardo, E-mail: hjhortuao@unal.edu.co, E-mail: lcastanedac@unal.edu.co [Grupo de Gravitación y Cosmología, Observatorio Astronómico Nacional, Universidad Nacional de Colombia, cra 45 No 26-85, Edificio Uriel Gutierréz, Bogotá, D.C. (Colombia)

2017-06-01

In this paper, we investigate the effects of helical primordial magnetic fields (PMFs) on the cosmic microwave background (CMB) reduced bispectrum. We derive the full three-point statistics of helical magnetic fields and numerically calculate the even contribution in the collinear configuration. We then numerically compute the CMB reduced bispectrum induced by passive and compensated PMF modes on large angular scales. There is a negative signal on the bispectrum due to the helical terms of the fields and we also observe that the biggest contribution to the bispectrum comes from the non-zero IR cut-off for causal fields, unlike the two-point correlation case. For negative spectral indices, the reduced bispectrum is enhanced by the passive modes. This gives a lower value of the upper limit for the mean amplitude of the magnetic field on a given characteristic scale. However, high values of IR cut-off in the bispectrum, and the helical terms of the magnetic field relaxes this bound. This demonstrates the importance of the IR cut-off and helicity in the study of the nature of PMFs from CMB observations.

Effect of Integrated Pest Management Training on Ugandan Small-Scale Farmers

DEFF Research Database (Denmark)

Clausen, Anna Sabine; Jørs, Erik; Atuhaire, Aggrey

2017-01-01

Small-scale farmers in developing countries use hazardous pesticides taking few or no safety measures. Farmer field schools (FFSs) teaching integrated pest management (IPM) have been shown to reduce pesticide use among trained farmers. This cross-sectional study compares pesticide-related knowledge......-reported symptoms. The study supports IPM as a method to reduce pesticide use and potential exposure and to improve pesticide-related KAP among small-scale farmers in developing countries....

New scale-down methodology from commercial to lab scale to optimize plant-derived soft gel capsule formulations on a commercial scale.

Science.gov (United States)

Oishi, Sana; Kimura, Shin-Ichiro; Noguchi, Shuji; Kondo, Mio; Kondo, Yosuke; Shimokawa, Yoshiyuki; Iwao, Yasunori; Itai, Shigeru

2018-01-15

A new scale-down methodology from commercial rotary die scale to laboratory scale was developed to optimize a plant-derived soft gel capsule formulation and eventually manufacture superior soft gel capsules on a commercial scale, in order to reduce the time and cost for formulation development. Animal-derived and plant-derived soft gel film sheets were prepared using an applicator on a laboratory scale and their physicochemical properties, such as tensile strength, Young's modulus, and adhesive strength, were evaluated. The tensile strength of the animal-derived and plant-derived soft gel film sheets was 11.7 MPa and 4.41 MPa, respectively. The Young's modulus of the animal-derived and plant-derived soft gel film sheets was 169 MPa and 17.8 MPa, respectively, and both sheets showed a similar adhesion strength of approximately 4.5-10 MPa. Using a D-optimal mixture design, plant-derived soft gel film sheets were prepared and optimized by varying their composition, including variations in the mass of κ-carrageenan, ι-carrageenan, oxidized starch and heat-treated starch. The physicochemical properties of the sheets were evaluated to determine the optimal formulation. Finally, plant-derived soft gel capsules were manufactured using the rotary die method and the prepared soft gel capsules showed equivalent or superior physical properties compared with pre-existing soft gel capsules. Therefore, we successfully developed a new scale-down methodology to optimize the formulation of plant-derived soft gel capsules on a commercial scale. Copyright © 2017 Elsevier B.V. All rights reserved.

A system approach for reducing the environmental impact of manufacturing and sustainability improvement of nano-scale manufacturing

Science.gov (United States)

Yuan, Yingchun

This dissertation develops an effective and economical system approach to reduce the environmental impact of manufacturing. The system approach is developed by using a process-based holistic method for upstream analysis and source reduction of the environmental impact of manufacturing. The system approach developed consists of three components of a manufacturing system: technology, energy and material, and is useful for sustainable manufacturing as it establishes a clear link between manufacturing system components and its overall sustainability performance, and provides a framework for environmental impact reductions. In this dissertation, the system approach developed is applied for environmental impact reduction of a semiconductor nano-scale manufacturing system, with three case scenarios analyzed in depth on manufacturing process improvement, clean energy supply, and toxic chemical material selection. The analysis on manufacturing process improvement is conducted on Atomic Layer Deposition of Al2O3 dielectric gate on semiconductor microelectronics devices. Sustainability performance and scale-up impact of the ALD technology in terms of environmental emissions, energy consumption, nano-waste generation and manufacturing productivity are systematically investigated and the ways to improve the sustainability of the ALD technology are successfully developed. The clean energy supply is studied using solar photovoltaic, wind, and fuel cells systems for electricity generation. Environmental savings from each clean energy supply over grid power are quantitatively analyzed, and costs for greenhouse gas reductions on each clean energy supply are comparatively studied. For toxic chemical material selection, an innovative schematic method is developed as a visual decision tool for characterizing and benchmarking the human health impact of toxic chemicals, with a case study conducted on six chemicals commonly used as solvents in semiconductor manufacturing. Reliability of

Scaling considerations for modeling the in situ vitrification process

International Nuclear Information System (INIS)

Langerman, M.A.; MacKinnon, R.J.

1990-09-01

Scaling relationships for modeling the in situ vitrification waste remediation process are documented based upon similarity considerations derived from fundamental principles. Requirements for maintaining temperature and electric potential field similarity between the model and the prototype are determined as well as requirements for maintaining similarity in off-gas generation rates. A scaling rationale for designing reduced-scale experiments is presented and the results are assessed numerically. 9 refs., 6 figs

Defensive effects of extrafloral nectaries in quaking aspen differ with scale.

Science.gov (United States)

Mortensen, Brent; Wagner, Diane; Doak, Patricia

2011-04-01

The effects of plant defenses on herbivory can differ among spatial scales. This may be particularly common with indirect defenses, such as extrafloral nectaries (EFNs), that attract predatory arthropods and are dependent on predator distribution, abundance, and behavior. We tested the defensive effects of EFNs in quaking aspen (Populus tremuloides Michx.) against damage by a specialist herbivore, the aspen leaf miner (Phyllocnistis populiella Cham.), at the scale of individual leaves and entire ramets (i.e., stems). Experiments excluding crawling arthropods revealed that the effects of aspen EFNs differed at the leaf and ramet scales. Crawling predators caused similar reductions in the percent leaf area mined on individual leaves with and without EFNs. However, the extent to which crawling predators increased leaf miner mortality and, consequently, reduced mining damage increased with EFN expression at the ramet scale. Thus, aspen EFNs provided a diffuse defense, reducing damage to leaves across a ramet regardless of leaf-scale EFN expression. We detected lower leaf miner damage and survival unassociated with crawling predators on EFN-bearing leaves, suggesting that direct defenses (e.g., chemical defenses) were stronger on leaves with than without EFNs. Greater direct defenses on EFN-bearing leaves may reduce the probability of losing these leaves and thus weakening ramet-scale EFN defense. Aspen growth was not related to EFN expression or the presence of crawling predators over the course of a single season. Different effects of aspen EFNs at the leaf and ramet scales suggest that future studies may benefit from examining indirect defenses simultaneously at multiple scales.

Reducing weight precision of convolutional neural networks towards large-scale on-chip image recognition

Science.gov (United States)

Ji, Zhengping; Ovsiannikov, Ilia; Wang, Yibing; Shi, Lilong; Zhang, Qiang

2015-05-01

In this paper, we develop a server-client quantization scheme to reduce bit resolution of deep learning architecture, i.e., Convolutional Neural Networks, for image recognition tasks. Low bit resolution is an important factor in bringing the deep learning neural network into hardware implementation, which directly determines the cost and power consumption. We aim to reduce the bit resolution of the network without sacrificing its performance. To this end, we design a new quantization algorithm called supervised iterative quantization to reduce the bit resolution of learned network weights. In the training stage, the supervised iterative quantization is conducted via two steps on server - apply k-means based adaptive quantization on learned network weights and retrain the network based on quantized weights. These two steps are alternated until the convergence criterion is met. In this testing stage, the network configuration and low-bit weights are loaded to the client hardware device to recognize coming input in real time, where optimized but expensive quantization becomes infeasible. Considering this, we adopt a uniform quantization for the inputs and internal network responses (called feature maps) to maintain low on-chip expenses. The Convolutional Neural Network with reduced weight and input/response precision is demonstrated in recognizing two types of images: one is hand-written digit images and the other is real-life images in office scenarios. Both results show that the new network is able to achieve the performance of the neural network with full bit resolution, even though in the new network the bit resolution of both weight and input are significantly reduced, e.g., from 64 bits to 4-5 bits.

Large-scale solar heat

Energy Technology Data Exchange (ETDEWEB)

Tolonen, J.; Konttinen, P.; Lund, P. [Helsinki Univ. of Technology, Otaniemi (Finland). Dept. of Engineering Physics and Mathematics

1998-12-31

In this project a large domestic solar heating system was built and a solar district heating system was modelled and simulated. Objectives were to improve the performance and reduce costs of a large-scale solar heating system. As a result of the project the benefit/cost ratio can be increased by 40 % through dimensioning and optimising the system at the designing stage. (orig.)

Reduced egfr, elevated urine protein and low level of personal protective equipment compliance among artisanal small scale gold miners at Bibiani-Ghana: a cross-sectional study.

Science.gov (United States)

Afrifa, Justice; Essien-Baidoo, Samuel; Ephraim, Richard K D; Nkrumah, Daniel; Dankyira, Daniel Osei

2017-06-27

Mercury is a toxic metal with its effects on human health ranging from acute to chronic in a very short time of exposure. Artisanal and small-scale gold mining (ASGM) is the main source of direct human exposure to mercury. To access the effect of mercury exposure on the renal function and level of personal protective equipment (PPE) compliance among small-scale gold miners in Bibiani District of the Western Region of Ghana METHOD: 110 consenting male gold miners were purposively recruited for this study. A structured questionnaire was used to collect socio-demographic information from the participants. Work place assessment and interviews were conducted. Urine samples were analysed for protein; blood was analysed for mercury and creatinine. Estimated glomerular filtration rate (eGFR) was calculated using the chronic kidney disease-epidemiology collaboration (CKD-EPI) equation. Of the 110 participants, 61(55.5%) exceeded the occupational exposure threshold (blood mercury <5μg/L). Urine protein (41.72±68.34, P<0.0001), serum creatinine (2.24±1.19, P<0.0001) and blood mercury (18.37±10.47, P<0.0001) were significantly elevated among the exposed group compared to the non-exposed group. However, the exposed group had a significantly reduced eGFR (P<0.0001). There was a significant correlation (r=0.7338, p<0.0001) between blood mercury concentration and urine protein concentration. An increase in blood mercury correlated negatively (r = -0.8233, P<0.0001) with eGFR among the exposed group. High urine protein (P< 0.0001) and high serum creatinine (P< 0.0001) were significantly associated with increased mercury exposure. Increased mercury exposure was significantly associated with burning of amalgam (P=0.0196), sucking of excess mercury (P=0.0336), longer work duration (P=0.0314) and low educational background (P=0.0473). Small scale miners at the Bibiani work site are exposed to excess mercury. Proteinuria and reduced eGFR is common in mine workers exposed to excess

Optimal Scale Edge Detection Utilizing Noise within Images

Directory of Open Access Journals (Sweden)

Adnan Khashman

2003-04-01

Full Text Available Edge detection techniques have common problems that include poor edge detection in low contrast images, speed of recognition and high computational cost. An efficient solution to the edge detection of objects in low to high contrast images is scale space analysis. However, this approach is time consuming and computationally expensive. These expenses can be marginally reduced if an optimal scale is found in scale space edge detection. This paper presents a new approach to detecting objects within images using noise within the images. The novel idea is based on selecting one optimal scale for the entire image at which scale space edge detection can be applied. The selection of an ideal scale is based on the hypothesis that "the optimal edge detection scale (ideal scale depends on the noise within an image". This paper aims at providing the experimental evidence on the relationship between the optimal scale and the noise within images.

Consumer detection and acceptability of reduced-sodium bread.

Science.gov (United States)

La Croix, Kimberly W; Fiala, Steven C; Colonna, Ann E; Durham, Catherine A; Morrissey, Michael T; Drum, Danna K; Kohn, Melvin A

2015-06-01

Bread is the largest contributor of Na to the American diet and excess Na consumption contributes to premature death and disability. We sought to determine the Na level at which consumers could detect a difference between reduced-Na bread and bread with typical Na content, and to determine if consumer sensory acceptability and purchase intent differed between reduced-Na bread and bread with typical Na content. Difference testing measured ability to detect differences in control bread and reduced-Na bread using two-alternative forced choice testing. Acceptability was measured using a nine-point hedonic scale and purchase intent was measured using a five-point purchase intent scale. Difference and acceptability testing were conducted in Portland, OR, USA in January 2013. Eighty-two consumers participated in difference testing and 109 consumers participated in acceptability testing. Consumers did not detect a difference in saltiness between the control bread and the 10 % reduced-Na bread, but did detect a difference between the control bread and bread reduced in Na content by 20 % and 30 %. Na reductions had no effect on consumer acceptability of sensory characteristics, including overall liking, appearance, aroma, flavour, sweetness, salt level and texture, or purchase intent. Reducing Na levels by up to 30 % in the sandwich bread tested did not affect consumer liking or purchase intent of the product. These results support national recommendations for small, incremental Na reductions in the food supply over time and assure bread manufacturers that sensory characteristics and consumer purchase intent of their products will be preserved after Na reductions occur.

Land-Atmosphere Coupling in the Multi-Scale Modelling Framework

Science.gov (United States)

Kraus, P. M.; Denning, S.

2015-12-01

The Multi-Scale Modeling Framework (MMF), in which cloud-resolving models (CRMs) are embedded within general circulation model (GCM) gridcells to serve as the model's cloud parameterization, has offered a number of benefits to GCM simulations. The coupling of these cloud-resolving models directly to land surface model instances, rather than passing averaged atmospheric variables to a single instance of a land surface model, the logical next step in model development, has recently been accomplished. This new configuration offers conspicuous improvements to estimates of precipitation and canopy through-fall, but overall the model exhibits warm surface temperature biases and low productivity.This work presents modifications to a land-surface model that take advantage of the new multi-scale modeling framework, and accommodate the change in spatial scale from a typical GCM range of ~200 km to the CRM grid-scale of 4 km.A parameterization is introduced to apportion modeled surface radiation into direct-beam and diffuse components. The diffuse component is then distributed among the land-surface model instances within each GCM cell domain. This substantially reduces the number excessively low light values provided to the land-surface model when cloudy conditions are modeled in the CRM, associated with its 1-D radiation scheme. The small spatial scale of the CRM, ~4 km, as compared with the typical ~200 km GCM scale, provides much more realistic estimates of precipitation intensity, this permits the elimination of a model parameterization of canopy through-fall. However, runoff at such scales can no longer be considered as an immediate flow to the ocean. Allowing sub-surface water flow between land-surface instances within the GCM domain affords better realism and also reduces temperature and productivity biases.The MMF affords a number of opportunities to land-surface modelers, providing both the advantages of direct simulation at the 4 km scale and a much reduced

A full scale approximation of covariance functions for large spatial data sets

KAUST Repository

Sang, Huiyan

2011-10-10

Gaussian process models have been widely used in spatial statistics but face tremendous computational challenges for very large data sets. The model fitting and spatial prediction of such models typically require O(n 3) operations for a data set of size n. Various approximations of the covariance functions have been introduced to reduce the computational cost. However, most existing approximations cannot simultaneously capture both the large- and the small-scale spatial dependence. A new approximation scheme is developed to provide a high quality approximation to the covariance function at both the large and the small spatial scales. The new approximation is the summation of two parts: a reduced rank covariance and a compactly supported covariance obtained by tapering the covariance of the residual of the reduced rank approximation. Whereas the former part mainly captures the large-scale spatial variation, the latter part captures the small-scale, local variation that is unexplained by the former part. By combining the reduced rank representation and sparse matrix techniques, our approach allows for efficient computation for maximum likelihood estimation, spatial prediction and Bayesian inference. We illustrate the new approach with simulated and real data sets. © 2011 Royal Statistical Society.

A full scale approximation of covariance functions for large spatial data sets

KAUST Repository

Sang, Huiyan; Huang, Jianhua Z.

2011-01-01

Gaussian process models have been widely used in spatial statistics but face tremendous computational challenges for very large data sets. The model fitting and spatial prediction of such models typically require O(n 3) operations for a data set of size n. Various approximations of the covariance functions have been introduced to reduce the computational cost. However, most existing approximations cannot simultaneously capture both the large- and the small-scale spatial dependence. A new approximation scheme is developed to provide a high quality approximation to the covariance function at both the large and the small spatial scales. The new approximation is the summation of two parts: a reduced rank covariance and a compactly supported covariance obtained by tapering the covariance of the residual of the reduced rank approximation. Whereas the former part mainly captures the large-scale spatial variation, the latter part captures the small-scale, local variation that is unexplained by the former part. By combining the reduced rank representation and sparse matrix techniques, our approach allows for efficient computation for maximum likelihood estimation, spatial prediction and Bayesian inference. We illustrate the new approach with simulated and real data sets. © 2011 Royal Statistical Society.

A randomized control study of psychological intervention to reduce anxiety, amotivation and psychological distress among medical students

OpenAIRE

Coumaravelou Saravanan; Rajiah Kingston

2014-01-01

Background: Test anxiety aggravates psychological distress and reduces the motivation among graduate students. This study aimed to identify psychological intervention for test anxiety, which reduces the level of psychological distress, amotivation and increases the intrinsic and extrinsic motivation among medical students. Materials and Methods: Westside test anxiety scale, Kessler Perceived Stress Scale and Academic Motivation Scale were used to measure test anxiety, psychological distress a...

Reduced wear of enamel with novel fine and nano-scale leucite glass-ceramics.

Science.gov (United States)

Theocharopoulos, Antonios; Chen, Xiaohui; Hill, Robert; Cattell, Michael J

2013-06-01

Leucite glass-ceramics used to produce all-ceramic restorations can suffer from brittle fracture and wear the opposing teeth. High strength and fine crystal sized leucite glass-ceramics have recently been reported. The objective of this study is to investigate whether fine and nano-scale leucite glass-ceramics with minimal matrix microcracking are associated with a reduction in in vitro tooth wear. Human molar cusps (n=12) were wear tested using a Bionix-858 testing machine (300,000 simulated masticatory cycles) against experimental fine crystal sized (FS), nano-scale crystal sized (NS) leucite glass-ceramics and a commercial leucite glass-ceramic (Ceramco-3, Dentsply, USA). Wear was imaged using Secondary Electron Imaging (SEI) and quantified using white-light profilometry. Both experimental groups were found to produce significantly (pceramic) loss than the FS group. Increased waviness and damage was observed on the wear surfaces of the Ceramco-3 glass-ceramic disc/tooth group in comparison to the experimental groups. This was also indicated by higher surface roughness values for the Ceramco-3 glass-ceramic disc/tooth group. Fine and nano-sized leucite glass-ceramics produced a reduction in in vitro tooth wear. The high strength low wear materials of this study may help address the many problems associated with tooth enamel wear and restoration failure. Copyright © 2013 Elsevier Ltd. All rights reserved.

Quantum interference between two phonon paths and reduced heat transport in diamond lattice with atomic-scale planar defects

Science.gov (United States)

Kosevich, Yu. A.; Strelnikov, I. A.

2018-02-01

Destructive quantum interference between the waves propagating through laterally inhomogeneous layer can result in their total reflection, which in turn reduces energy flux carried by these waves. We consider the systems of Ge atoms, which fully or partly, in the chequer-wise order, fill a crystal plane in diamond-like Si lattice. We have revealed that a single type of the atomic defects, which are placed in identical positions in different unit cells in the defect crystal plane, can result in double transmission antiresonances of phonon wave packets. This new effect we relate with the complex structure of the diamond-like unit cell, which comprises two atoms in different positions and results in two distinct vibration resonances in two interfering phonon paths. We also consider the propagation of phonon wave packets in the superlatticies made of the defect planes, half-filled in the chequer-wise order with Ge atoms. We have revealed relatively broad phonon stop bands with center frequencies at the transmission antiresonances. We elaborate the equivalent analytical quasi-1D lattice model of the two phonon paths through the complex planar defect in the diamond-like lattice and describe the reduction of phonon heat transfer through the atomic-scale planar defects.

Development of small-scale peat production; Pienturvetuotannon kehittaeminen

Energy Technology Data Exchange (ETDEWEB)

Erkkilae, A.; Kallio, E. [VTT Energy, Jyvaeskylae (Finland)

1997-12-01

The aim of the project is to develop production conditions, methods and technology of small-scale peat production to such a level that the productivity is improved and competitivity maintained. The aim in 1996 was to survey the present status of small-scale peat production, and research and development needs and to prepare a development plan for small-scale peat production for a continued project in 1997 and for the longer term. A questionnaire was sent to producers by mail, and its results were completed by phone interviews. Response was obtained from 164 producers, i.e. from about 75 - 85 % of small-scale peat producers. The quantity of energy peat produced by these amounted to 3.3 TWh and that of other peat to 265 000 m{sup 3}. The total production of energy peat (large- scale producers Vapo Oy and Turveruukki Oy included) amounted to 25.0 TWh in 1996 in Finland, of which 91 % (22.8 TWh) was milled peat and 9 % (2.2 TWh) of sod peat. The total production of peat other than energy peat amounted to 1.4 million m{sup 3}. The proportion of small-scale peat production was 13 % of energy peat, 11 % of milled peat and 38 % of sod peat. The proportion of small-scale producers was 18 % of other peat production. The results deviate clearly from those obtained in a study of small-scale production in the 1980s. The amount of small-scale production is clearly larger than generally assessed. Small-scale production focuses more on milled peat than on sod peat. The work will be continued in 1997. Based on development needs appeared in the questionnaire, the aim is to reduce environmental impacts and runoff effluents from small- scale production, to increase the efficiency of peat deliveries and to reduce peat production costs by improving the service value of machines by increasing co-operative use. (orig.)

A practical process for light-water detritiation at large scales

Energy Technology Data Exchange (ETDEWEB)

Boniface, H.A. [Atomic Energy of Canada Limited, Chalk River, ON (Canada); Robinson, J., E-mail: jr@tyne-engineering.com [Tyne Engineering, Burlington, ON (Canada); Gnanapragasam, N.V.; Castillo, I.; Suppiah, S. [Atomic Energy of Canada Limited, Chalk River, ON (Canada)

2014-07-01

AECL and Tyne Engineering have recently completed a preliminary engineering design for a modest-scale tritium removal plant for light water, intended for installation at AECL's Chalk River Laboratories (CRL). This plant design was based on the Combined Electrolysis and Catalytic Exchange (CECE) technology developed at CRL over many years and demonstrated there and elsewhere. The general features and capabilities of this design have been reported as well as the versatility of the design for separating any pair of the three hydrogen isotopes. The same CECE technology could be applied directly to very large-scale wastewater detritiation, such as the case at Fukushima Daiichi Nuclear Power Station. However, since the CECE process scales linearly with throughput, the required capital and operating costs are substantial for such large-scale applications. This paper discusses some options for reducing the costs of very large-scale detritiation. Options include: Reducing tritium removal effectiveness; Energy recovery; Improving the tolerance of impurities; Use of less expensive or more efficient equipment. A brief comparison with alternative processes is also presented. (author)

Refining a self-assessment of informatics competency scale using Mokken scaling analysis.

Science.gov (United States)

Yoon, Sunmoo; Shaffer, Jonathan A; Bakken, Suzanne

2015-01-01

Healthcare environments are increasingly implementing health information technology (HIT) and those from various professions must be competent to use HIT in meaningful ways. In addition, HIT has been shown to enable interprofessional approaches to health care. The purpose of this article is to describe the refinement of the Self-Assessment of Nursing Informatics Competencies Scale (SANICS) using analytic techniques based upon item response theory (IRT) and discuss its relevance to interprofessional education and practice. In a sample of 604 nursing students, the 93-item version of SANICS was examined using non-parametric IRT. The iterative modeling procedure included 31 steps comprising: (1) assessing scalability, (2) assessing monotonicity, (3) assessing invariant item ordering, and (4) expert input. SANICS was reduced to an 18-item hierarchical scale with excellent reliability. Fundamental skills for team functioning and shared decision making among team members (e.g. "using monitoring systems appropriately," "describing general systems to support clinical care") had the highest level of difficulty, and "demonstrating basic technology skills" had the lowest difficulty level. Most items reflect informatics competencies relevant to all health professionals. Further, the approaches can be applied to construct a new hierarchical scale or refine an existing scale related to informatics attitudes or competencies for various health professions.

The Expanded Large Scale Gap Test

Science.gov (United States)

1987-03-01

NSWC TR 86-32 DTIC THE EXPANDED LARGE SCALE GAP TEST BY T. P. LIDDIARD D. PRICE RESEARCH AND TECHNOLOGY DEPARTMENT ’ ~MARCH 1987 Ap~proved for public...arises, to reduce the spread in the LSGT 50% gap value.) The worst charges, such as those with the highest or lowest densities, the largest re-pressed...Arlington, VA 22217 PE 62314N INS3A 1 RJ14E31 7R4TBK 11 TITLE (Include Security CIlmsilficatiorn The Expanded Large Scale Gap Test . 12. PEIRSONAL AUTHOR() T

A geometric hierarchy for the supersymmetry breaking scale

International Nuclear Information System (INIS)

Oakley, C.; Ross, G.G.

1983-01-01

F type supersymmetry breaking through O'Raifeartaigh-Fayet (Nucl. Phys.; B96:331 (1975) and Phys. Lett.; 580:67 (1975)) potentials is considered. It is shown how a class of models gives rise to a supersymmetry breaking scale reduced relative to the fundamental scale M of the potential by powers of (M/Msub(Planck)). The role of R invariance in such potentials is discussed. (author)

Scaling analysis in bepu licensing of LWR

International Nuclear Information System (INIS)

D'auria, Francesco; Lanfredini, Marco; Muellner, Nikolaus

2012-01-01

'Scaling' plays an important role for safety analyses in the licensing of water cooled nuclear power reactors. Accident analyses, a sub set of safety analyses, is mostly based on nuclear reactor system thermal hydraulics, and therefore based on an adequate experimental data base, and in recent licensing applications, on best estimate computer code calculations. In the field of nuclear reactor technology, only a small set of the needed experiments can be executed at a nuclear power plant; the major part of experiments, either because of economics or because of safety concerns, has to be executed at reduced scale facilities. How to address the scaling issue has been the subject of numerous investigations in the past few decades (a lot of work has been performed in the 80thies and 90thies of the last century), and is still the focus of many scientific studies. The present paper proposes a 'roadmap' to scaling. Key elements are the 'scaling-pyramid', related 'scaling bridges' and a logical path across scaling achievements (which constitute the 'scaling puzzle'). The objective is addressing the scaling issue when demonstrating the applicability of the system codes, the 'key-to-scaling', in the licensing process of a nuclear power plant. The proposed 'road map to scaling' aims at solving the 'scaling puzzle', by introducing a unified approach to the problem.

Research on large area VUV-sensitive gaseous photomultipliers for cryogenic applications

Science.gov (United States)

Coimbra, Artur Emanuel Cardoso

Desde cedo que a comunidade cientifica compreendeu que gases nobres em liquido sao excelentes meios de deteccao de radiacao, combinando a sua elevada densidade, elevado grau de homogeneidade e de elevado rendimento de cintilacao. Para alem destas caracteristicas inerentes, estes tem a potencialidade de fornecer ambos sinais de ionizacao - criando electroes livres - e cintilacao em resposta a interaccao com radiacao ionizante e, tendo em vista a sua aplicacao em experiencias de eventos raros relacionados com fisica de neutrinos ou materia-escura, a capacidade de autoblindagem garante a exclusao de eventos induzidos por radiacao de fundo. O facto de nao absorverem a sua propria luz, emergente dos eventos de cintilacao, permite a expansao deste tipo de detectores ate grandes volumes, sendo que as colaboracoes mais recentes propoem detectores com dezenas de toneladas de xenon em estado liquido. As experiencias actuais que usam gases nobres em estado liquido empregam xenon ou argon numa so fase (estado liquido) ou em dupla-fase (estado liquido + gasoso) e as suas aplicacoes abrangem desde as ja referidas experiencias de procura de eventos raros, passando por imagiologia medica tais como detectores de radiacao gama para PET ou câmaras Compton "3-gamma" em combinacao com PET, passando tambem por aplicacoes de seguranca como sistemas de inspeccao para deteccao de material fissil e, finalmente, em câmaras Compton para aplicacoes de astrofisica. Em ambas as configuracoes a leitura dos sinais de cintilacao e geralmente feita atraves de um grande numero de dispendiosos fotomultiplicadores de vacuo agrupados. A presente tese de doutoramento e dedicada aos fotomultiplicadores gasosos de grande area para aplicacoes criogenicas desenvolvidos no contexto do programa doutoral, tendo em vista a sua eventual aplicacao como um dispositivo complementar aos metodos existentes de deteccao de cintilacao, para aplicacao em futuras experiencias de grande escala. Esta pesquisa foi

Thermography for detection of scaling in slurry lines and process vessels

International Nuclear Information System (INIS)

Capolingua, Adam; Petrik, Andrew

2006-01-01

A major problem in many of today's refineries and mineral processing plants is internal scale build-up within slurry lines and process vessels. Consequences of such an internal scale build-up within lines and vessels include machinery damage, flow restrictions, blockages and localised pipe wear. These problems lead to a loss of production, increased maintenance costs, impinge on worker safety, increase environmental hazards and inevitably reduces profit for the organisation of concern. Hence, the application of an efficient and accurate non-intrusive detection method for locating internal scale within kilometres of lines and numerous process vessels is imperative to reduce maintenance costs and limit production losses. Thermography has been found to be a very useful NDT technique for applications where there is a differential between the ambient and internal product temperatures. The 'insulating' effect of the internal scaling results in a reduced external temperature over the associated area. These temperature differentials can be efficiently detected via a thermographic scan. While this technique is relatively straightforward, the interpretation of the thermographic images usually requires reasonable skill and experience to assess the true extent of each problem detected. In some cases, the true location and extent of scaling within the slurry lines may not be thermally obvious due to the nature of the internal scaling. In such cases, the use of other complementary methods to effectively 'listen'in to the lines has proved to be a valuable procedure. In particular a technology that is typically used in vibration monitoring to assess bearing and gear degradation has been successfully applied in conjunction with thermography to assess lines with localised or dislodged scale. This paper presents a number of case studies where thermography was either applied independently or in conjunction with other measurement techniques, to detect and assess different internal

Considerations for reducing food system energy demand while scaling up urban agriculture

DEFF Research Database (Denmark)

Mohareb, Eugene; Heller, Martin; Novak, Paige

2017-01-01

-income countries, considering UA classification, direct/indirect energy pressures, and interactions with other components of the food-energy-water nexus. This is followed by an exploration of ways in which these cities can plan for the exploitation of waste flows for resource-efficient UA...... with UA systems, highlighting that the literature is not yet sufficiently robust to make universal claims on benefits. This letter explores energy demand from conventional resource inputs, various production systems, water/energy trade-offs, alternative irrigation, packaging materials, and transportation...... of the proposed benefits of UA; however, explicit consideration of energy and resource requirements needs to be made in order to realize these anticipated environmental benefits. A literature review is undertaken here to provide new insight into the energy implications of scaling up UA in cities in high...

Complete coverage of reduced graphene oxide on silicon dioxide substrates

International Nuclear Information System (INIS)

Jingfeng Huang; Hu Chen; Yoong Alfred Tok Iing; Larisika, Melanie; Nowak, Christoph; Faulkner, Steve; Nimmo, Myra A.

2014-01-01

Reduced graphene oxide (RGO) has the advantage of an aqueous and industrial-scale production route. No other approaches can rival the RGO field effect transistor platform in terms of cost (scale). However the large deviations in the electrical resistivity of this fabricated material prevent it from being used widely. After an ethanol chemical vapor deposition (CVD) post-treatment to graphene oxide with ethanol, carbon islets are deposited preferentially at the edges of existing flakes. With a 2-h treatment, the standard deviation in electrical resistance of the treated chips can be reduced by 99.95%. Thus this process could enable RGO to be used in practical electronic devices. (special topic — international conference on nanoscience and technology, china 2013)

Application of relative permeability modifier additives to reduce water production in different formations; Aplicacao de aditivos modificadores de permeabilidade relativa para reducao da producao de agua em diferentes formacoes

Energy Technology Data Exchange (ETDEWEB)

Melo, Ricardo C.B.; Torres, Ricardo S.; Pedrosa Junior, Helio; Dean, Gregory [BJ Services do Brasil Ltda., RJ (Brazil)

2004-07-01

Today most oil companies would be better described as water companies. Total worldwide oil production averages some 75 million barrels per day and, while estimates vary, this is associated with the production of 300 - 400 million barrels of water per day. These values of approximately 5 - 6 barrels of water for every barrel of oil are quite conservative. In the United States, where many fields are depleted, the ratio of water-to-oil production is closer to 9 to 1. In some areas around the world, fields remain on production when the ratio is as high as 48 to 1. Numerous strategies, both mechanical and chemical, have been employed over the years in attempts to achieve reduction in water production. Simple shut-off techniques, using cement, mechanical plugs and cross-linked gels have been widely used. Exotic materials such as DPR (disproportionate permeability reducers) and or new generation of relative permeability modifiers (RPM) have been applied in radial treatments with varying degrees of success. Most recently 'Conformance Fracturing' operations have increased substantially in mature fields as the synergistic effect obtained by adding a RPM to a fracturing fluid have produced increased oil production with reduced water cut in one step, consequently eliminating the cost of additional water shut off treatment later on. This paper presents laboratory testing and worldwide case histories of applications of various RPM materials, at different permeability and temperatures. The paper also describes technical design and operational methodology that we believe to have a significant impact in the development strategies of many fields worldwide. (author)

Representações sociais dos usuários hospitalizados sobre cidadania: implicações para o cuidado hospitalar

Directory of Open Access Journals (Sweden)

Flávia Pacheco de Araújo

2016-08-01

Full Text Available RESUMO Objetivo: analisar as representacoes sociais de usuarios hospitalizados sobre a cidadania no cuidado hospitalar. Método: abordagem qualitativa com referencial da Teoria das Representacoes Sociais, realizada com 31 usuarios hospitalizados no setor de clinica medica de um hospital publico, universitario. Realizou-se entrevista semiestruturada, cujos dados foram submetidos ao programa Alceste, com aplicacao de analise lexical. Resultados: os usuarios conhecem os seus direitos, e a cidadania no cuidado e entendida a luz dos direitos a saude, de modo que sejam bem atendidos do ponto de vista tecnico e humano. Conclusão: o bom trato relacional e a prestacao do cuidado tecnico-procedimental sao direitos dos usuarios; logo, a ausência de um ou de outra implica o nao respeito a sua cidadania.

Fast ignition breakeven scaling

International Nuclear Information System (INIS)

Slutz, Stephen A.; Vesey, Roger Alan

2005-01-01

A series of numerical simulations have been performed to determine scaling laws for fast ignition break even of a hot spot formed by energetic particles created by a short pulse laser. Hot spot break even is defined to be when the fusion yield is equal to the total energy deposited in the hot spot through both the initial compression and the subsequent heating. In these simulations, only a small portion of a previously compressed mass of deuterium-tritium fuel is heated on a short time scale, i.e., the hot spot is tamped by the cold dense fuel which surrounds it. The hot spot tamping reduces the minimum energy required to obtain break even as compared to the situation where the entire fuel mass is heated, as was assumed in a previous study [S. A. Slutz, R. A. Vesey, I. Shoemaker, T. A. Mehlhorn, and K. Cochrane, Phys. Plasmas 7, 3483 (2004)]. The minimum energy required to obtain hot spot break even is given approximately by the scaling law E T = 7.5(ρ/100) -1.87 kJ for tamped hot spots, as compared to the previously reported scaling of E UT = 15.3(ρ/100) -1.5 kJ for untamped hotspots. The size of the compressed fuel mass and the focusability of the particles generated by the short pulse laser determines which scaling law to use for an experiment designed to achieve hot spot break even

Elaboration of reduced versions of Measurement tools: A practical Perspective

Directory of Open Access Journals (Sweden)

Nekane Balluerka

2012-01-01

Full Text Available The aim of the present study is to show, from a practical perspective, the guidelines that may be followed to create a reduced version of a measurement tool. Therefore, it describes in detail the process of creating the reduced Basque version of the CDS scale (Children's Depression Scale; Lang and Tisher, 1978, which measures depression in children and adolescents. In a first study, the items that make up the reduced version of the CDS (CDS-R are selected from a set of analysis conducted on a sample of 886 children and adolescents who were administered the extensive version of the CDS adapted to the Basque language (Balluerka, Gorostiaga, and Haranburu, 2012. Subsequently, the CDS-R is validated on a sample of 2,165 participants. This second study examines the factorial structure, the internal consistency and the temporal stability of the instrument, as well as the relationship between its dimensions and gender, academic performance, emotional intelligence and attachment. Thus, evidence is obtained on the reliability and validity of the reduced version of the instrument, which guarantees suitable evaluation of the construct the instrument is intended to measure.

Scaling analysis in bepu licensing of LWR

Energy Technology Data Exchange (ETDEWEB)

D' auria, Francesco; Lanfredini, Marco; Muellner, Nikolaus [University of Pisa, Pisa (Italy)

2012-08-15

'Scaling' plays an important role for safety analyses in the licensing of water cooled nuclear power reactors. Accident analyses, a sub set of safety analyses, is mostly based on nuclear reactor system thermal hydraulics, and therefore based on an adequate experimental data base, and in recent licensing applications, on best estimate computer code calculations. In the field of nuclear reactor technology, only a small set of the needed experiments can be executed at a nuclear power plant; the major part of experiments, either because of economics or because of safety concerns, has to be executed at reduced scale facilities. How to address the scaling issue has been the subject of numerous investigations in the past few decades (a lot of work has been performed in the 80thies and 90thies of the last century), and is still the focus of many scientific studies. The present paper proposes a 'roadmap' to scaling. Key elements are the 'scaling-pyramid', related 'scaling bridges' and a logical path across scaling achievements (which constitute the 'scaling puzzle'). The objective is addressing the scaling issue when demonstrating the applicability of the system codes, the 'key-to-scaling', in the licensing process of a nuclear power plant. The proposed 'road map to scaling' aims at solving the 'scaling puzzle', by introducing a unified approach to the problem.

Role of two insect growth regulators in integrated pest management of citrus scales.

Science.gov (United States)

Grafton-Cardwell, E E; Lee, J E; Stewart, J R; Olsen, K D

2006-06-01

Portions of two commercial citrus orchards were treated for two consecutive years with buprofezin or three consecutive years with pyriproxyfen in a replicated plot design to determine the long-term impact of these insect growth regulators (IGRs) on the San Joaquin Valley California integrated pest management program. Pyriproxyfen reduced the target pest, California red scale, Aonidiella aurantii Maskell, to nondetectable levels on leaf samples approximately 4 mo after treatment. Pyriproxyfen treatments reduced the California red scale parasitoid Aphytis melinus DeBach to a greater extent than the parasitoid Comperiella bifasciata Howard collected on sticky cards. Treatments of lemons Citrus limon (L.) Burm. f. infested with scale parasitized by A. melinus showed only 33% direct mortality of the parasitoid, suggesting the population reduction observed on sticky cards was due to low host density. Three years of pyriproxyfen treatments did not maintain citricola scale, Coccus pseudomagnoliarum (Kuwana), below the treatment threshold and cottony cushion scale, Icerya purchasi Maskell, was slowly but incompletely controlled. Buprofezin reduced California red scale to very low but detectable levels approximately 5 mo after treatment. Buprofezin treatments resulted in similar levels of reduction of the two parasitoids A. melinus and C. bifasciata collected on sticky cards. Treatments of lemons infested with scale parasitized by A. melinus showed only 7% mortality of the parasitoids, suggesting the population reduction observed on sticky cards was due to low host density. Citricola scale was not present in this orchard, and cottony cushion scale was slowly and incompletely controlled by buprofezin. These field plots demonstrated that IGRs can act as organophosphate insecticide replacements for California red scale control; however, their narrower spectrum of activity and disruption of coccinellid beetles can allow other scale species to attain primary pest status.

Large-Scale Optimization for Bayesian Inference in Complex Systems

Energy Technology Data Exchange (ETDEWEB)

Willcox, Karen [MIT; Marzouk, Youssef [MIT

2013-11-12

The SAGUARO (Scalable Algorithms for Groundwater Uncertainty Analysis and Robust Optimization) Project focused on the development of scalable numerical algorithms for large-scale Bayesian inversion in complex systems that capitalize on advances in large-scale simulation-based optimization and inversion methods. The project was a collaborative effort among MIT, the University of Texas at Austin, Georgia Institute of Technology, and Sandia National Laboratories. The research was directed in three complementary areas: efficient approximations of the Hessian operator, reductions in complexity of forward simulations via stochastic spectral approximations and model reduction, and employing large-scale optimization concepts to accelerate sampling. The MIT--Sandia component of the SAGUARO Project addressed the intractability of conventional sampling methods for large-scale statistical inverse problems by devising reduced-order models that are faithful to the full-order model over a wide range of parameter values; sampling then employs the reduced model rather than the full model, resulting in very large computational savings. Results indicate little effect on the computed posterior distribution. On the other hand, in the Texas--Georgia Tech component of the project, we retain the full-order model, but exploit inverse problem structure (adjoint-based gradients and partial Hessian information of the parameter-to-observation map) to implicitly extract lower dimensional information on the posterior distribution; this greatly speeds up sampling methods, so that fewer sampling points are needed. We can think of these two approaches as ``reduce then sample'' and ``sample then reduce.'' In fact, these two approaches are complementary, and can be used in conjunction with each other. Moreover, they both exploit deterministic inverse problem structure, in the form of adjoint-based gradient and Hessian information of the underlying parameter-to-observation map, to

Frequency scaling for angle gathers

KAUST Repository

Zuberi, M. A H; Alkhalifah, Tariq Ali

2014-01-01

Angle gathers provide an extra dimension to analyze the velocity after migration. Space-shift and time shift-imaging conditions are two methods used to obtain angle gathers, but both are reasonably expensive. By scaling the time-lag axis of the time-shifted images, the computational cost of the time shift imaging condition can be considerably reduced. In imaging and more so Full waveform inversion, frequencydomain Helmholtz solvers are used more often to solve for the wavefields than conventional time domain extrapolators. In such cases, we do not need to extend the image, instead we scale the frequency axis of the frequency domain image to obtain the angle gathers more efficiently. Application on synthetic data demonstrate such features.

Ultralow-Energy Wireless Smart-Scales System with Micropower Generator

Science.gov (United States)

Kitamura, Kazuma; Yano, Hironori; Mochizuki, Misako; Takano, Tomoaki; Yamauchi, Hironori; Douseki, Takakuni

A wireless smart-scales system with a face recognition function has been developed as an application for wireless sensor networks. The face recognition employs a wireless camera; and the system automatically identifies a person and stores the weights of all the people that use the system on a server. Two key ultralow-energy circuit techniques were devised for the smart scales. One is a nearly-zero-standby-current circuit that combines a mechanical switch and an electrical CPU-controlled power switch; it reduces the standby power dissipation of the CPU from 1.5 mW to less than 0.1 μW. The other is a super-intermittently-operating circuit with a power-switch transistor and a small resistance; it suppresses the energy dissipation of the wireless camera to just 1/4 of the total energy dissipation. Furthermore, an electromechanical micropower generator with electromagnetic induction further reduces the energy dissipation. It is located under the scales and supplies a power of 75 mW during one second.

Large-scale synthesis of reduced graphene oxides with uniformly coated polyaniline for supercapacitor applications.

Science.gov (United States)

Salunkhe, Rahul R; Hsu, Shao-Hui; Wu, Kevin C W; Yamauchi, Yusuke

2014-06-01

We report an effective route for the preparation of layered reduced graphene oxide (rGO) with uniformly coated polyaniline (PANI) layers. These nanocomposites are synthesized by chemical oxidative polymerization of aniline monomer in the presence of layered rGO. SEM, TEM, X-ray photoelectron spectroscopy (XPS), FTIR, and Raman spectroscopy analysis results demonstrated that reduced graphene oxide-polyaniline (rGO-PANI) nanocomposites are successfully synthesized. Because of synergistic effects, rGO-PANI nanocomposites prepared by this approach exhibit excellent capacitive performance with a high specific capacitance of 286 F g(-1) and high cycle reversibility of 94 % after 2000 cycles. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

SINEX: SCALE shielding analysis GUI for X-Windows

International Nuclear Information System (INIS)

Browman, S.M.; Barnett, D.L.

1997-12-01

SINEX (SCALE Interface Environment for X-windows) is an X-Windows graphical user interface (GUI), that is being developed for performing SCALE radiation shielding analyses. SINEX enables the user to generate input for the SAS4/MORSE and QADS/QAD-CGGP shielding analysis sequences in SCALE. The code features will facilitate the use of both analytical sequences with a minimum of additional user input. Included in SINEX is the capability to check the geometry model by generating two-dimensional (2-D) color plots of the geometry model using a new version of the SCALE module, PICTURE. The most sophisticated feature, however, is the 2-D visualization display that provides a graphical representation on screen as the user builds a geometry model. This capability to interactively build a model will significantly increase user productivity and reduce user errors. SINEX will perform extensive error checking and will allow users to execute SCALE directly from the GUI. The interface will also provide direct on-line access to the SCALE manual

Factor Structure of Child Behavior Scale Scores in Peruvian Preschoolers

Science.gov (United States)

Meyer, Erin L.; Schaefer, Barbara A.; Soto, Cesar Merino; Simmons, Crystal S.; Anguiano, Rebecca; Brett, Jeremy; Holman, Alea; Martin, Justin F.; Hata, Heidi K.; Roberts, Kimberly J.; Mello, Zena R.; Worrell, Frank C.

2011-01-01

Behavior rating scales aid in the identification of problem behaviors, as well as the development of interventions to reduce such behavior. Although scores on many behavior rating scales have been validated in the United States, there have been few such studies in other cultural contexts. In this study, the structural validity of scores on a…

Design of a holographic micro-scale spectrum-splitting photovoltaic system

Science.gov (United States)

Wu, Yuechen; Vorndran, Shelby; Ayala Pelaez, Silvana; Russo, Juan M.; Kostuk, Raymond K.

2015-09-01

Micro-scale PV technology combines the high conversion efficiency of concentrated photovoltaics (CPV) with the low costs and the simple form of flat panel PV. Some of the benefits of micro-scale PV include: reduced semiconductor material usage; improved heat rejection capacity; and more versatile PV cell interconnect configurations. Spectrumsplitting is also a beneficial technique to increase the efficiency and reduce the cost of photovoltaic systems. It spatially separates the incident solar spectrum into spectral components and directs them to PV cells with matching bandgaps. This approach avoids the current and lattice matching problems that exist in tandem multi-junction systems. In this paper, we applied the ideas of spectrum-splitting in a micro-scale PV system, and demonstrated a holographic micro-scale spectrum-splitting photovoltaic system. This system consists of a volume transmission hologram in combination with a micro-lens array. An analysis methodology was developed to design the system and determine the performance of the resulting system. The spatial characteristics of the dispersed spectrum, the overall system conversion efficiency, and the improvement over best bandgap will be discussed.

Analysis of scaled-factorial-moment data

International Nuclear Information System (INIS)

Seibert, D.

1990-01-01

We discuss the two standard constructions used in the search for intermittency, the exclusive and inclusive scaled factorial moments. We propose the use of a new scaled factorial moment that reduces to the exclusive moment in the appropriate limit and is free of undesirable multiplicity correlations that are contained in the inclusive moment. We show that there are some similarities among most of the models that have been proposed to explain factorial-moment data, and that these similarities can be used to increase the efficiency of testing these models. We begin by calculating factorial moments from a simple independent-cluster model that assumes only approximate boost invariance of the cluster rapidity distribution and an approximate relation among the moments of the cluster multiplicity distribution. We find two scaling laws that are essentially model independent. The first scaling law relates the moments to each other with a simple formula, indicating that the different factorial moments are not independent. The second scaling law relates samples with different rapidity densities. We find evidence for much larger clusters in heavy-ion data than in light-ion data, indicating possible spatial intermittency in the heavy-ion events

Energy reduction through voltage scaling and lightweight checking

Science.gov (United States)

Kadric, Edin

As the semiconductor roadmap reaches smaller feature sizes and the end of Dennard Scaling, design goals change, and managing the power envelope often dominates delay minimization. Voltage scaling remains a powerful tool to reduce energy. We find that it results in about 60% geomean energy reduction on top of other common low-energy optimizations with 22nm CMOS technology. However, when voltage is reduced, it becomes easier for noise and particle strikes to upset a node, potentially causing Silent Data Corruption (SDC). The 60% energy reduction, therefore, comes with a significant drop in reliability. Duplication with checking and triple-modular redundancy are traditional approaches used to combat transient errors, but spending 2--3x the energy for redundant computation can diminish or reverse the benefits of voltage scaling. As an alternative, we explore the opportunity to use checking operations that are cheaper than the base computation they are guarding. We devise a classification system for applications and their lightweight checking characteristics. In particular, we identify and evaluate the effectiveness of lightweight checks in a broad set of common tasks in scientific computing and signal processing. We find that the lightweight checks cost only a fraction of the base computation (0-25%) and allow us to recover the reliability losses from voltage scaling. Overall, we show about 50% net energy reduction without compromising reliability compared to operation at the nominal voltage. We use FPGAs (Field-Programmable Gate Arrays) in our work, although the same ideas can be applied to different systems. On top of voltage scaling, we explore other common low-energy techniques for FPGAs: transmission gates, gate boosting, power gating, low-leakage (high-Vth) processes, and dual-V dd architectures. We do not scale voltage for memories, so lower voltages help us reduce logic and interconnect energy, but not memory energy. At lower voltages, memories become dominant

Successful up-scaled population interventions to reduce risk factors for non-communicable disease in adults: results from the International Community Interventions for Health (CIH) Project in China, India and Mexico.

Science.gov (United States)

Dyson, Pamela A; Anthony, Denis; Fenton, Brenda; Stevens, Denise E; Champagne, Beatriz; Li, Li-Ming; Lv, Jun; Ramírez Hernández, Jorge; Thankappan, K R; Matthews, David R

2015-01-01

Non-communicable disease (NCD) is increasing rapidly in low and middle-income countries (LMIC), and is associated with tobacco use, unhealthy diet and physical inactivity. There is little evidence for up-scaled interventions at the population level to reduce risk in LMIC. The Community Interventions for Health (CIH) program was a population-scale community intervention study with comparator population group undertaken in communities in China, India, and Mexico, each with populations between 150,000-250,000. Culturally appropriate interventions were delivered over 18-24 months. Two independent cross-sectional surveys of a stratified sample of adults aged 18-64 years were conducted at baseline and follow-up. A total of 6,194 adults completed surveys at baseline, and 6,022 at follow-up. The proportion meeting physical activity recommendations decreased significantly in the control group (C) (44.1 to 30.2%), but not in the intervention group (I) (38.0 to 36.1%), p<0.001. Those eating ≥ 5 portions of fruit and vegetables daily decreased significantly in C (19.2 to 17.2%), but did not change in I (20.0 to 19.6%,), p=0.013. The proportion adding salt to food was unchanged in C (24.9 to 25.3%) and decreased in I (25.9 to 19.6%), p<0.001. Prevalence of obesity increased in C (8.3 to 11.2%), with no change in I (8.6 to 9.7%,) p=0.092. Concerning tobacco, for men the difference-in-difference analysis showed that the reduction in use was significantly greater in I compared to C (p=0.014). Up-scaling known health promoting interventions designed to reduce the incidence of NCD in whole communities in LMIC is feasible, and has measurable beneficial outcomes on risk factors for NCD, namely tobacco use, diet, and physical inactivity.

Successful up-scaled population interventions to reduce risk factors for non-communicable disease in adults: results from the International Community Interventions for Health (CIH Project in China, India and Mexico.

Directory of Open Access Journals (Sweden)

Pamela A Dyson

Full Text Available Non-communicable disease (NCD is increasing rapidly in low and middle-income countries (LMIC, and is associated with tobacco use, unhealthy diet and physical inactivity. There is little evidence for up-scaled interventions at the population level to reduce risk in LMIC.The Community Interventions for Health (CIH program was a population-scale community intervention study with comparator population group undertaken in communities in China, India, and Mexico, each with populations between 150,000-250,000. Culturally appropriate interventions were delivered over 18-24 months. Two independent cross-sectional surveys of a stratified sample of adults aged 18-64 years were conducted at baseline and follow-up.A total of 6,194 adults completed surveys at baseline, and 6,022 at follow-up. The proportion meeting physical activity recommendations decreased significantly in the control group (C (44.1 to 30.2%, but not in the intervention group (I (38.0 to 36.1%, p<0.001. Those eating ≥ 5 portions of fruit and vegetables daily decreased significantly in C (19.2 to 17.2%, but did not change in I (20.0 to 19.6%,, p=0.013. The proportion adding salt to food was unchanged in C (24.9 to 25.3% and decreased in I (25.9 to 19.6%, p<0.001. Prevalence of obesity increased in C (8.3 to 11.2%, with no change in I (8.6 to 9.7%, p=0.092. Concerning tobacco, for men the difference-in-difference analysis showed that the reduction in use was significantly greater in I compared to C (p=0.014.Up-scaling known health promoting interventions designed to reduce the incidence of NCD in whole communities in LMIC is feasible, and has measurable beneficial outcomes on risk factors for NCD, namely tobacco use, diet, and physical inactivity.

Advanced modeling to accelerate the scale up of carbon capture technologies

Energy Technology Data Exchange (ETDEWEB)

Miller, David C.; Sun, XIN; Storlie, Curtis B.; Bhattacharyya, Debangsu

2015-06-01

In order to help meet the goals of the DOE carbon capture program, the Carbon Capture Simulation Initiative (CCSI) was launched in early 2011 to develop, demonstrate, and deploy advanced computational tools and validated multi-scale models to reduce the time required to develop and scale-up new carbon capture technologies. This article focuses on essential elements related to the development and validation of multi-scale models in order to help minimize risk and maximize learning as new technologies progress from pilot to demonstration scale.

Phosphorus transfer in surface runoff from intensive pasture systems at various scales: a review.

Science.gov (United States)

Dougherty, Warwick J; Fleming, Nigel K; Cox, Jim W; Chittleborough, David J

2004-01-01

Phosphorus transfer in runoff from intensive pasture systems has been extensively researched at a range of scales. However, integration of data from the range of scales has been limited. This paper presents a conceptual model of P transfer that incorporates landscape effects and reviews the research relating to P transfer at a range of scales in light of this model. The contribution of inorganic P sources to P transfer is relatively well understood, but the contribution of organic P to P transfer is still relatively poorly defined. Phosphorus transfer has been studied at laboratory, profile, plot, field, and watershed scales. The majority of research investigating the processes of P transfer (as distinct from merely quantifying P transfer) has been undertaken at the plot scale. However, there is a growing need to integrate data gathered at a range of scales so that more effective strategies to reduce P transfer can be identified. This has been hindered by the lack of a clear conceptual framework to describe differences in the processes of P transfer at the various scales. The interaction of hydrological (transport) factors with P source factors, and their relationship to scale, require further examination. Runoff-generating areas are highly variable, both temporally and spatially. Improvement in the understanding and identification of these areas will contribute to increased effectiveness of strategies aimed at reducing P transfers in runoff. A thorough consideration of scale effects using the conceptual model of P transfer outlined in this paper will facilitate the development of improved strategies for reducing P losses in runoff.

Categorical scaling of partial loudness in a condition of masking release.

Science.gov (United States)

Verhey, Jesko L; Heeren, Wiebke

2015-08-01

Categorical loudness scaling was used to measure suprathreshold release from masking. The signal was a 986-Hz sinusoid that was embedded in a bandpass-filtered masking noise. This noise was either unmodulated or was amplitude modulated with a square-wave modulator. The unmodulated noise had either the same level as the modulated noise or had a level that was reduced by the difference in thresholds for the 986-Hz signal obtained with the modulated and unmodulated noise masker presented at the same level (i.e., the masking release). A comparison with loudness matching data of the same set of subjects showed that the data obtained with loudness scaling capture main aspects of the change in suprathreshold perception of the sinusoid when the masker was modulated. The scaling data for the signal masked by the unmodulated noise with the reduced masker level were similar to that for the signal embedded in the modulated noise. This similarity supports the hypothesis that the mechanism eliciting the masking release is effectively reducing the masker level.

Reducing Current Spread using Current Focusing in Cochlear Implant Users

Science.gov (United States)

Landsberger, David M.; Padilla, Monica; Srinivasan, Arthi G.

2012-01-01

Cochlear implant performance in difficult listening situations is limited by channel interactions. It is known that partial tripolar (PTP) stimulation reduces the spread of excitation (SOE). However, the greater the degree of current focusing, the greater the absolute current required to maintain a fixed loudness. As current increases, so does SOE. In experiment 1, the SOE for equally loud stimuli with different degrees of current focusing is measured via a forward-masking procedure. Results suggest that at a fixed loudness, some but not all patients have a reduced SOE with PTP stimulation. Therefore, it seems likely that a PTP speech processing strategy could improve spectral resolution for only those patients with a reduced SOE. In experiment 2, the ability to discriminate different levels of current focusing was measured. In experiment 3, patients subjectively scaled verbal descriptors of stimuli of various levels of current focusing. Both discrimination and scaling of verbal descriptors correlated well with SOE reduction, suggesting that either technique have the potential to be used clinically to quickly predict which patients would receive benefit from a current focusing strategy. PMID:22230370

The silicon chip: A versatile micro-scale platform for micro- and nano-scale systems

Science.gov (United States)

Choi, Edward

Cutting-edge advances in micro- and nano-scale technology require instrumentation to interface with the external world. While technology feature sizes are continually being reduced, the size of experimentalists and their instrumentation do not mirror this trend. Hence there is a need for effective application-specific instrumentation to bridge the gap from the micro and nano-scale phenomena being studied to the comparative macro-scale of the human interfaces. This dissertation puts forward the idea that the silicon CMOS integrated circuit, or microchip in short, serves as an excellent platform to perform this functionality. The electronic interfaces designed for the semiconductor industry are particularly attractive as development platforms, and the reduction in feature sizes that has been a hallmark of the industry suggests that chip-scale instrumentation may be more closely coupled to the phenomena of interest, allowing finer control or improved measurement capabilities. Compatibility with commercial processes will further enable economies of scale through mass production, another welcome feature of this approach. Thus chip-scale instrumentation may replace the bulky, expensive, cumbersome-to-operate macro-scale prototypes currently in use for many of these applications. The dissertation examines four specific applications in which the chip may serve as the ideal instrumentation platform. These are nanorod manipulation, polypyrrole bilayer hinge microactuator control, organic transistor hybrid circuits, and contact fluorescence imaging. The thesis is structured around chapters devoted to each of these projects, in addition to a chapter on preliminary work on an RFID system that serves as a wireless interface model. Each of these chapters contains tools and techniques developed for chip-scale instrumentation, from custom scripts for automated layout and data collection to microfabrication processes. Implementation of these tools to develop systems for the

Novel polymeric phosphonate scale inhibitors for improved squeeze treatment lifetimes

Energy Technology Data Exchange (ETDEWEB)

Jackson, G.E.; Poynton, N.; McLaughlin, K.; Clark, D.R.

1996-12-31

New patented chemistry has provided an exciting discovery which may be used to reduce costs in scale squeeze applications. Phosphomethylated polyamines (PMPAs) have been found to possess outstanding adsorption-desorption properties which generate long squeeze lifetimes. This paper describes the core-flood tests and modelling work, which highlight these properties, plus additional scale inhibition performance studies to demonstrate the all-round capabilities of this chemistry for squeeze treatments. An example of a PMPA is used to show the extremely viable adsorption and desorption isotherms. These illustrate the efficient way in which the desorption occurs to minimise the chemical in the returns with a benefit of reduced chemical content in the discharge. The PMPA also demonstrates that both polymer and phosphonate properties can be embraced in a single product (e.g. dual scale control mechanisms) confirming that this chemistry is a true polymeric phosphonate. 13 refs., 12 figs., 1 tab.

The Parenting to Reduce Adolescent Depression and Anxiety Scale: Assessing parental concordance with parenting guidelines for the prevention of adolescent depression and anxiety disorders

Directory of Open Access Journals (Sweden)

Mairead C. Cardamone-Breen

2017-09-01

Full Text Available Background Despite substantial evidence demonstrating numerous parental risk and protective factors for the development of adolescent depression and anxiety disorders, there is currently no single measure that assesses these parenting factors. To address this gap, we developed the Parenting to Reduce Adolescent Depression and Anxiety Scale (PRADAS as a criterion-referenced measure of parental concordance with a set of evidence-based parenting guidelines for the prevention of adolescent depression and anxiety disorders. In this paper, we used a sample of Australian parents of adolescents to: (1 validate the PRADAS as a criterion-referenced measure; (2 examine parental concordance with the guidelines in the sample; and (3 examine correlates of parental concordance with the guidelines. Methods Seven hundred eleven parents completed the PRADAS, as well as two established parenting measures, and parent-report measures of adolescent depression and anxiety symptoms. Six hundred sixty adolescent participants (aged 12–15 also completed the symptom measures. Concordance with the guidelines was assessed via nine subscale scores and a total score. Reliability of the scores was assessed with an estimate of the agreement coefficient, as well as 1-month test-retest reliability. Convergent validity was examined via correlations between the scale and two established parenting measures. Results One proposed subscale was removed from the final version of the scale, resulting in a total of eight subscales. Reliability was high for the total score, and acceptable to high for seven of the eight subscales. One-month test-retest reliability was acceptable to high for the total score. Convergent validity was supported by moderate to high correlations with two established measures of parenting. Overall, rates of parental concordance with the guidelines were low in our sample. Higher scores were associated with being female and higher levels of parental education

Impact of the heavy quark matching scales in PDF fits

Energy Technology Data Exchange (ETDEWEB)

Bertone, V. [VU Univ., Amsterdam (Netherlands). Dept. of Physics and Astronomy; Nikhef Theory Goup, Amsterdam (Netherlands); Britzger, D. [DESY, Hamburg (Germany); Camarda, S. [CERN, Geneva (Switzerland); Collaboration: The xFitter Developers' Team; and others

2017-07-15

We investigate the impact of displaced heavy quark matching scales in a global fit. The heavy quark matching scale μ{sub m} determines at which energy scale μ the QCD theory transitions from N{sub F} to N{sub F}+1 in the Variable Flavor Number Scheme (VFNS) for the evolution of the Parton Distribution Functions (PDFs) and strong coupling α{sub S}(μ). We study the variation of the matching scales, and their impact on a global PDF fit of the combined HERA data. As the choice of the matching scale μ{sub m} effectively is a choice of scheme, this represents a theoretical uncertainty; ideally, we would like to see minimal dependence on this parameter. For the transition across the charm quark (from N{sub F}=3 to 4), we find a large μ{sub m}=μ{sub c} dependence of the global fit χ{sup 2} at NLO, but this is significantly reduced at NNLO. For the transition across the bottom quark (from N{sub F}=4 to 5), we have a reduced μ{sub m}=μ{sub b} dependence of the χ{sup 2} at both NLO and NNLO as compared to the charm. This feature is now implemented in xFitter 2.0.0, an open source QCD fit framework.

Scaling and design report of ECC performance test facility (SWAT) of SMART

International Nuclear Information System (INIS)

Cho, Seok; Ko, Yong Ju; Cho, Young Il; Kim, Jeong Tak; Choi, Nam Hyun; Shin Yong Chul; Park, Choon Kyong; Kwon, Tae Soon; Lee, Sung Jae

2010-12-01

SWAT (SMART ECC Water Asymmetric Two-phase choking test facility) was designed by 1/5 scaling ratio using the modified linear scaling method. The design characteristics of the SMART such that the elevation of RCP suction nozzles is the same with that of the ECC injection nozzles are maintained to reduce a distortion caused by the gravitational effect. Thermal hydraulic phenomena in a test facility designed by the modified linear scaling method can be simulated more accurately than those by the full-height and reduced area scaling method. The main part of the test section is SG-side upper down-comer. The boundary conditions are saturated steam and water flow condition and drain flow rate to control the collapsed water level in the down-comer. The test data of the SWAT can produce the well-defined boundary condition to validate the thermal hydraulic analysis code for the SMART

Scaling and design report of ECC performance test facility (SWAT) of SMART

Energy Technology Data Exchange (ETDEWEB)

Cho, Seok; Ko, Yong Ju; Cho, Young Il; Kim, Jeong Tak; Choi, Nam Hyun; Shin Yong Chul; Park, Choon Kyong; Kwon, Tae Soon; Lee, Sung Jae [KAERI, Daejeon (Korea, Republic of)

2010-12-15

SWAT (SMART ECC Water Asymmetric Two-phase choking test facility) was designed by 1/5 scaling ratio using the modified linear scaling method. The design characteristics of the SMART such that the elevation of RCP suction nozzles is the same with that of the ECC injection nozzles are maintained to reduce a distortion caused by the gravitational effect. Thermal hydraulic phenomena in a test facility designed by the modified linear scaling method can be simulated more accurately than those by the full-height and reduced area scaling method. The main part of the test section is SG-side upper down-comer. The boundary conditions are saturated steam and water flow condition and drain flow rate to control the collapsed water level in the down-comer. The test data of the SWAT can produce the well-defined boundary condition to validate the thermal hydraulic analysis code for the SMART

New Designs of Reduced-Order Observer-Based Controllers for Singularly Perturbed Linear Systems

Directory of Open Access Journals (Sweden)

Heonjong Yoo

2017-01-01

Full Text Available The slow and fast reduced-order observers and reduced-order observer-based controllers are designed by using the two-stage feedback design technique for slow and fast subsystems. The new designs produce an arbitrary order of accuracy, while the previously known designs produce the accuracy of O(ϵ only where ϵ is a small singular perturbation parameter. Several cases of reduced-order observer designs are considered depending on the measured state space variables: only all slow variables are measured, only all fast variables are measured, and some combinations of the slow and fast variables are measured. Since the two-stage methods have been used to overcome the numerical ill-conditioning problem for Cases (III–(V, they have similar procedures. The numerical ill-conditioning problem is avoided so that independent feedback controllers can be applied to each subsystem. The design allows complete time-scale separation for both the reduced-order observer and controller through the complete and exact decomposition into slow and fast time scales. This method reduces both offline and online computations.

Phenomenology of scaled factorial moments and future approaches for correlation studies

International Nuclear Information System (INIS)

Seibert, D.

1991-01-01

We show that the definitions of the exclusive and inclusive scaled factorial moments are not equivalent, and propose the use of scaled factorial moments that reduce to the exclusive moments in the case of fixed multiplicity. We then present a new derivation of the multiplicity scaling law for scaled factorial moment data. This scaling law seems to hold, independent of collision energy, for events with fixed projectile and target. However, deviations from this scaling law indicate that correlations in S-Au collisions are 30 times as strong as correlations in hadronic collisions. Finally, we discuss 'split-bin' correlation functions, the most useful tool for future investigations of these anomalously strong hadronic correlations. (orig.)

Novel algorithm of large-scale simultaneous linear equations

International Nuclear Information System (INIS)

Fujiwara, T; Hoshi, T; Yamamoto, S; Sogabe, T; Zhang, S-L

2010-01-01

We review our recently developed methods of solving large-scale simultaneous linear equations and applications to electronic structure calculations both in one-electron theory and many-electron theory. This is the shifted COCG (conjugate orthogonal conjugate gradient) method based on the Krylov subspace, and the most important issue for applications is the shift equation and the seed switching method, which greatly reduce the computational cost. The applications to nano-scale Si crystals and the double orbital extended Hubbard model are presented.

UP-scaling of inverted small molecule based organic solar cells

DEFF Research Database (Denmark)

Patil, Bhushan Ramesh; Madsen, Morten

Organic solar cells (OSC), in spite of being a promising technology, still face challenges regarding large-scale fabrication. Although efficiencies of up to 12 % has been reached for small molecule OSC, their performance, both in terms of device efficiency and stability, is significantly reduced...... during up-scaling processes. The work presented here is focused on an approach towards up-scaling of small molecule based OSC with inverted device configuration. Bilayer OSC from Tetraphenyldibenzoperiflanthene (DBP) and Fullerenes (C70), as electron donor and acceptor respectively, with cell area...

End-of-pipe single-sludge denitrification in pilot-scale recirculating aquaculture systems

DEFF Research Database (Denmark)

Suhr, Karin Isabel; Pedersen, Lars-Flemming; Nielsen, J.L.

2014-01-01

A step toward environmental sustainability of recirculat aquaculture systems (RAS) is implementation ofsingle-sludge denitrification, a process eliminating nitrate from the aqueous environment while reduc-ing the organic matter discharge simultaneously. Two 1700 L pilot-scale RAS systems each...

Reduction experiment of iron scale by adding waste plastics.

Science.gov (United States)

Zhang, Chongmin; Chen, Shuwen; Miao, Xincheng; Yuan, Hao

2009-01-01

The special features of waste plastics in China are huge in total amount, various in type and dispersive in deposition. Therefore, it is necessary to try some new ways that are fit to Chinese situation for disposing waste plastics as metallurgical raw materials more effectively and flexibly. Owing to its high ferrous content and less impurity, the iron scale became ideal raw material to produce pure iron powder. One of the methods to produce pure iron powder is Hoganas Method, by which, after one or multistage of reduction steps, the iron scale can be reduced pure iron powder. However, combining utilization of waste plastics and iron powder production, a series of reduction experiments were arranged and investigated, which is hoped to take use of both thermal and chemical energy contained in waste plastics as well as to improve the reducing condition of iron scale, and hence to develop a new metallurgical way of disposing waste plastics. The results show that under these experimental conditions, the thermal-decomposition of water plastics can conduce to an increase of porosity in the reduction systems. Moreover, better thermodynamics and kinetics conditions for the reduction of scale can be reached. As a result, the reduction rate is increased.

Structural validity of a 16-item abridged version of the Cervantes Health-Related Quality of Life scale for menopause: the Cervantes Short-Form Scale.

Science.gov (United States)

Coronado, Pluvio J; Borrego, Rafael Sánchez; Palacios, Santiago; Ruiz, Miguel A; Rejas, Javier

2015-03-01

The Cervantes Scale is a specific health-related quality of life questionnaire that was originally developed in Spanish to be used in Spain for women through and beyond menopause. It contains 31 items and is time-consuming. The aim of this study was to produce an abridged version with the same dimensional structure and with similar psychometric properties. A representative sample of 516 postmenopausal women (mean [SD] age, 57 [4.31] y) seen in outpatient gynecology clinics and extracted from an observational cross-sectional study was used. Item analysis, internal consistency reliability, item-total and item-dimension correlations, and item correlation with the 12-item Medical Outcomes Study Short Form Health Survey Version 2.0 were studied. Dimensional and full-model confirmatory factor analyses were used to check structure stability. A threefold cross-validation method was used to obtain stable estimates by means of multigroup analysis. The scale was reduced to a 16-item version, the Cervantes Short-Form Scale, containing four main dimensions (Menopause and Health, Psychological, Sexuality, and Couple Relations), with the first dimension composed of three subdimensions (Vasomotor Symptoms, Health, and Aging). Goodness-of-fit statistics were better than those of the extended version (χ(2)/df = 2.493; adjusted goodness-of-fit index, 0.802; parsimony comparative fit index, 0.749; root mean standard error of approximation, 0.054). Internal consistency was good (Cronbach's α = 0.880). Correlations between the extended and the reduced dimensions were high and significant in all cases (P < 0.001; r values ranged from 0.90 for Sexuality to 0.969 for Vasomotor Symptoms). The Cervantes Scale can be reduced to a 16-item abridged version (Cervantes Short-Form Scale) that maintains the original dimensional structure and psychometric properties. At 51% of the original length, this version can be administered faster, making it especially suitable for routine medical practice.

Reactor similarity for plasma–material interactions in scaled-down tokamaks as the basis for the Vulcan conceptual design

International Nuclear Information System (INIS)

Whyte, D.G.; Olynyk, G.M.; Barnard, H.S.; Bonoli, P.T.; Bromberg, L.; Garrett, M.L.; Haakonsen, C.B.; Hartwig, Z.S.; Mumgaard, R.T.; Podpaly, Y.A.

2012-01-01

Highlights: ► Discussion of similarity scalings for reduced-size tokamaks. ► Proposal of a new set of scaling laws for divertor similarity. ► Discussion of how the new scaling provides fidelity to a reactor. ► The new scaling is used as the basis for the Vulcan conceptual design. - Abstract: Dimensionless parameter scaling techniques are a powerful tool in the study of complex physical systems, especially in tokamak fusion experiments where the cost of full-size devices is high. It is proposed that dimensionless similarity be used to study in a small-scale device the coupled issues of the scrape-off layer (SOL) plasma, plasma–material interactions (PMI), and the plasma-facing material (PFM) response expected in a tokamak fusion reactor. Complete similarity is not possible in a reduced-size device. In addition, “hard” technological limits on the achievable magnetic field and peak heat flux, as well as the necessity to produce non-inductive scenarios, must be taken into account. A practical approach is advocated, in which the most important dimensionless parameters are matched to a reactor in the reduced-size device, while relaxing those parameters which are far from a threshold in behavior. “Hard” technological limits are avoided, so that the reduced-size device is technologically feasible. A criticism on these grounds is offered of the “P/R” model, in which the ratio of power crossing the last closed flux surface (LCFS), P, to the device major radius, R, is held constant. A new set of scaling rules, referred to as the “P/S” scaling (where S is the LCFS area) or the “PMI” scaling, is proposed: (i) non-inductive, steady-state operation; (ii) P is scaled with R 2 so that LCFS areal power flux P/S is constant; (iii) magnetic field B constant; (iv) geometry (elongation, safety factor q * , etc.) constant; (v) volume-averaged core density scaled as n≈n ¯ e ∼R −2/7 ; and (vi) ambient wall material temperature T W,0 constant. It is

Pilot-scale continuous ultrasonic cleaning equipment reduces Listeria monocytogenes levels on conveyor belts.

Science.gov (United States)

Tolvanen, Riina; Lundén, Janne; Hörman, Ari; Korkeala, Hannu

2009-02-01

Ultrasonic cleaning of a conveyor belt was studied by building a pilot-scale conveyor with an ultrasonic cleaning bath. A piece of the stainless steel conveyor belt was contaminated with meat-based soil and Listeria monocytogenes strains (V1, V3, and B9) and incubated for 72 h to allow bacteria to attach to the conveyor belt surfaces. The effect of ultrasound with a potassium hydroxide-based cleaning detergent was determined by using the cleaning bath at 45 and 50 degrees C for 30 s with and without ultrasound. The detachment of L. monocytogenes from the conveyor belt caused by the ultrasonic treatment was significantly greater at 45 degrees C (independent samples t test, P conveyor belt is effective even with short treatment times.

Scale dependence and small-x behaviour of polarized parton distributions

International Nuclear Information System (INIS)

Ball, R.D.; Forte, S.; Ridolfi, G.

1995-01-01

We discuss perturbative evolution of the polarized structure function g 1 in the (x, Q 2 ) plane, with special regard to the small-x region. We determine g 1 in terms of polarized quark and gluon distributions using coefficient functions to order α s . At small x g 1 then displays substantial scale dependence, which necessarily implies a corresponding scale dependence in the large-x region. This scale dependence has significant consequences for the extraction of the first moment from the experimental data, reducing its value while increasing the error. Conversely, the scale dependence may be used to constrain the size of the polarized gluon distribution. ((orig.))

Scale dependence and small x behaviour of polarized parton distributions

CERN Document Server

Ball, R D; Ridolfi, G; Forte, S; Ridolfi, G

1995-01-01

We discuss perturbative evolution of the polarized structure function g_1 in the (x,Q^2) plane, with special regard to the small-x region. We determine g_1 in terms of polarized quark and gluon distributions using coefficient functions to order alpha_s. At small x g_1 then displays substantial scale dependence, which necessarily implies a corresponding scale dependence in the large-x region. This scale dependence has significant consequences for the extraction of the first moment from the experimental data, reducing its value while increasing the error. Conversely, the scale dependence may be used to constrain the size of the polarized gluon distribution.

Simulating Catchment Scale Afforestation for Mitigating Flooding

Science.gov (United States)

Barnes, M. S.; Bathurst, J. C.; Quinn, P. F.; Birkinshaw, S.

2016-12-01

After the 2013-14, and the more recent 2015-16, winter floods in the UK there were calls to 'forest the uplands' as a solution to reducing flood risk across the nation. However, the role of forests as a natural flood management practice remains highly controversial, due to a distinct lack of robust evidence into its effectiveness in reducing flood risk during extreme events. This project aims to improve the understanding of the impacts of upland afforestation on flood risk at the sub-catchment and full catchment scales. This will be achieved through an integrated fieldwork and modelling approach, with the use of a series of process based hydrological models to scale up and examine the effects forestry can have on flooding. Furthermore, there is a need to analyse the extent to which land management practices, catchment system engineering and the installation of runoff attenuation features (RAFs), such as engineered log jams, in headwater catchments can attenuate flood-wave movement, and potentially reduce downstream flood risk. Additionally, the proportion of a catchment or riparian reach that would need to be forested in order to achieve a significant impact on reducing downstream flooding will be defined. The consequential impacts of a corresponding reduction in agriculturally productive farmland and the potential decline of water resource availability will also be considered in order to safeguard the UK's food security and satisfy the global demand on water resources.

Supervised exercise reduces cancer-related fatigue: a systematic review

Directory of Open Access Journals (Sweden)

José F Meneses-Echávez

2015-01-01

Full Text Available Question: Does supervised physical activity reduce cancer-related fatigue? Design: Systematic review with meta-analysis of randomised trials. Participants: People diagnosed with any type of cancer, without restriction to a particular stage of diagnosis or treatment. Intervention: Supervised physical activity interventions (eg, aerobic, resistance and stretching exercise, defined as any planned or structured body movement causing an increase in energy expenditure, designed to maintain or enhance health-related outcomes, and performed with systematic frequency, intensity and duration. Outcome measures: The primary outcome measure was fatigue. Secondary outcomes were physical and functional wellbeing assessed using the Functional Assessment of Cancer Therapy Fatigue Scale, European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire, Piper Fatigue Scale, Schwartz Cancer Fatigue Scale and the Multidimensional Fatigue Inventory. Methodological quality, including risk of bias of the studies, was evaluated using the PEDro Scale. Results: Eleven studies involving 1530 participants were included in the review. The assessment of quality showed a mean score of 6.5 (SD 1.1, indicating a low overall risk of bias. The pooled effect on fatigue, calculated as a standardised mean difference (SMD using a random-effects model, was –1.69 (95% CI –2.99 to –0.39. Beneficial reductions in fatigue were also found with combined aerobic and resistance training with supervision (SMD = –0.41, 95% CI –0.70 to –0.13 and with combined aerobic, resistance and stretching training with supervision (SMD = –0.67, 95% CI –1.17 to –0.17. Conclusion: Supervised physical activity interventions reduce cancer-related fatigue. These findings suggest that combined aerobic and resistance exercise regimens with or without stretching should be included as part of rehabilitation programs for people who have been diagnosed with cancer

Deciding for Others Reduces Loss Aversion

DEFF Research Database (Denmark)

Andersson, Ola; Holm, Håkan J.; Tyran, Jean-Robert Karl

2016-01-01

We study risk taking on behalf of others, both when choices involve losses and when they do not. A large-scale incentivized experiment with subjects randomly drawn from the Danish population is conducted. We find that deciding for others reduces loss aversion. When choosing between risky prospects...... when losses loom. This finding is consistent with an interpretation of loss aversion as a bias in decision making driven by emotions and that these emotions are reduced when making decisions for others....... for which losses are ruled out by design, subjects make the same choices for themselves as for others. In contrast, when losses are possible, we find that the two types of choices differ. In particular, we find that subjects who make choices for themselves take less risk than those who decide for others...

Genome-scale biological models for industrial microbial systems.

Science.gov (United States)

Xu, Nan; Ye, Chao; Liu, Liming

2018-04-01

The primary aims and challenges associated with microbial fermentation include achieving faster cell growth, higher productivity, and more robust production processes. Genome-scale biological models, predicting the formation of an interaction among genetic materials, enzymes, and metabolites, constitute a systematic and comprehensive platform to analyze and optimize the microbial growth and production of biological products. Genome-scale biological models can help optimize microbial growth-associated traits by simulating biomass formation, predicting growth rates, and identifying the requirements for cell growth. With regard to microbial product biosynthesis, genome-scale biological models can be used to design product biosynthetic pathways, accelerate production efficiency, and reduce metabolic side effects, leading to improved production performance. The present review discusses the development of microbial genome-scale biological models since their emergence and emphasizes their pertinent application in improving industrial microbial fermentation of biological products.

SPACE BASED INTERCEPTOR SCALING

Energy Technology Data Exchange (ETDEWEB)

G. CANAVAN

2001-02-01

Space Based Interceptor (SBI) have ranges that are adequate to address rogue ICBMs. They are not overly sensitive to 30-60 s delay times. Current technologies would support boost phase intercept with about 150 interceptors. Higher acceleration and velocity could reduce than number by about a factor of 3 at the cost of heavier and more expensive Kinetic Kill Vehicles (KKVs). 6g SBI would reduce optimal constellation costs by about 35%; 8g SBI would reduce them another 20%. Interceptor ranges fall rapidly with theater missile range. Constellations increase significantly for ranges under 3,000 km, even with advanced interceptor technology. For distributed launches, these estimates recover earlier strategic scalings, which demonstrate the improved absentee ratio for larger or multiple launch areas. Constellations increase with the number of missiles and the number of interceptors launched at each. The economic estimates above suggest that two SBI per missile with a modest midcourse underlay is appropriate. The SBI KKV technology would appear to be common for space- and surface-based boost phase systems, and could have synergisms with improved midcourse intercept and discrimination systems. While advanced technology could be helpful in reducing costs, particularly for short range theater missiles, current technology appears adequate for pressing rogue ICBM, accidental, and unauthorized launches.

Development and Psychometric Validation of the Dementia Attitudes Scale

Directory of Open Access Journals (Sweden)

Melissa L. O'Connor

2010-01-01

Full Text Available This study employed qualitative construct mapping and factor analysis to construct a scale to measure attitudes toward dementia. Five family caregivers, five professionals, and five college students participated in structured interviews. Qualitative analysis of the interviews led to a 46-item scale, which was reduced to 20 items following principal axis factoring with two different samples: college students (=302 and certified nursing assistant students (=145. Confirmatory factor analysis was then conducted with another sample of college students (=157. The final scale, titled the Dementia Attitudes Scale (DAS, essentially had a two-factor structure; the factors were labeled “dementia knowledge” and “social comfort.” Total-scale Cronbach's alphas ranged 0.83–0.85. Evidence for convergent validity was promising, as the DAS correlated significantly with scales that measured ageism and attitudes toward disabilities (range of correlations = 0.44–0.55; mean correlation =0.50. These findings demonstrate the reliability and validity of the DAS, supporting its use as a research tool.

Multi-scale Material Parameter Identification Using LS-DYNA® and LS-OPT®

Energy Technology Data Exchange (ETDEWEB)

Stander, Nielen; Basudhar, Anirban; Basu, Ushnish; Gandikota, Imtiaz; Savic, Vesna; Sun, Xin; Choi, Kyoo Sil; Hu, Xiaohua; Pourboghrat, F.; Park, Taejoon; Mapar, Aboozar; Kumar, Shavan; Ghassemi-Armaki, Hassan; Abu-Farha, Fadi

2015-09-14

Ever-tightening regulations on fuel economy, and the likely future regulation of carbon emissions, demand persistent innovation in vehicle design to reduce vehicle mass. Classical methods for computational mass reduction include sizing, shape and topology optimization. One of the few remaining options for weight reduction can be found in materials engineering and material design optimization. Apart from considering different types of materials, by adding material diversity and composite materials, an appealing option in automotive design is to engineer steel alloys for the purpose of reducing plate thickness while retaining sufficient strength and ductility required for durability and safety. A project to develop computational material models for advanced high strength steel is currently being executed under the auspices of the United States Automotive Materials Partnership (USAMP) funded by the US Department of Energy. Under this program, new Third Generation Advanced High Strength Steel (i.e., 3GAHSS) are being designed, tested and integrated with the remaining design variables of a benchmark vehicle Finite Element model. The objectives of the project are to integrate atomistic, microstructural, forming and performance models to create an integrated computational materials engineering (ICME) toolkit for 3GAHSS. The mechanical properties of Advanced High Strength Steels (AHSS) are controlled by many factors, including phase composition and distribution in the overall microstructure, volume fraction, size and morphology of phase constituents as well as stability of the metastable retained austenite phase. The complex phase transformation and deformation mechanisms in these steels make the well-established traditional techniques obsolete, and a multi-scale microstructure-based modeling approach following the ICME [0]strategy was therefore chosen in this project. Multi-scale modeling as a major area of research and development is an outgrowth of the Comprehensive

Robust, small-scale cultivation platform for Streptomyces coelicolor

DEFF Research Database (Denmark)

Sohoni, Sujata Vijay; Bapat, Prashant Madhusudan; Lantz, Anna Eliasson

2012-01-01

rates of antibiotics. CONCLUSION: We observed good agreement of the physiological data obtained in the developed MTP platform with bench-scale. Hence, the described MTP-based screening platform has a high potential for investigation of secondary metabolite biosynthesis in Streptomycetes and other....... The MTP cultivations were found to behave similar to bench-scale in terms of growth rate, productivity and substrate uptake rate and so was the onset of antibiotic synthesis. Shake flask cultivations however, showed discrepancy with respect to morphology and had considerably reduced volumetric production...

Adaptative Techniques to Reduce Power in Digital Circuits

Directory of Open Access Journals (Sweden)

Bharadwaj Amrutur

2011-07-01

Full Text Available CMOS chips are engineered with sufficient performance margins to ensure that they meet the target performance under worst case operating conditions. Consequently, excess power is consumed for most cases when the operating conditions are more benign. This article will review a suite of dynamic power minimization techniques, which have been recently developed to reduce power consumption based on actual operating conditions. We will discuss commonly used techniques like Dynamic Power Switching (DPS, Dynamic Voltage and Frequency Scaling (DVS and DVFS and Adaptive Voltage Scaling (AVS. Recent efforts to extend these to cover threshold voltage adaptation via Dynamic Voltage and Threshold Scaling (DVTS will also be presented. Computation rate is also adapted to actual work load requirements via dynamically changing the hardware parallelism or by controlling the number of operations performed. These will be explained with some examples from the application domains of media and wireless signal processing.

The Diagnostic Apathia Scale predicts the ability to return to work following depression or anxiety

DEFF Research Database (Denmark)

Hellström, Lc; Eplov, Lf; Nordentoft, M

2014-01-01

, tiredness/fatigue, insomnia, and reduced ability to work and engage in personal interests. The scale was analysed for psychometric validity (scalability) and for its ability to predict RTW. Finally, the predictive validity of the Diagnostic Apathia Scale regarding RTW was compared with scales measuring...

Large-scale sequential quadratic programming algorithms

Energy Technology Data Exchange (ETDEWEB)

Eldersveld, S.K.

1992-09-01

The problem addressed is the general nonlinear programming problem: finding a local minimizer for a nonlinear function subject to a mixture of nonlinear equality and inequality constraints. The methods studied are in the class of sequential quadratic programming (SQP) algorithms, which have previously proved successful for problems of moderate size. Our goal is to devise an SQP algorithm that is applicable to large-scale optimization problems, using sparse data structures and storing less curvature information but maintaining the property of superlinear convergence. The main features are: 1. The use of a quasi-Newton approximation to the reduced Hessian of the Lagrangian function. Only an estimate of the reduced Hessian matrix is required by our algorithm. The impact of not having available the full Hessian approximation is studied and alternative estimates are constructed. 2. The use of a transformation matrix Q. This allows the QP gradient to be computed easily when only the reduced Hessian approximation is maintained. 3. The use of a reduced-gradient form of the basis for the null space of the working set. This choice of basis is more practical than an orthogonal null-space basis for large-scale problems. The continuity condition for this choice is proven. 4. The use of incomplete solutions of quadratic programming subproblems. Certain iterates generated by an active-set method for the QP subproblem are used in place of the QP minimizer to define the search direction for the nonlinear problem. An implementation of the new algorithm has been obtained by modifying the code MINOS. Results and comparisons with MINOS and NPSOL are given for the new algorithm on a set of 92 test problems.

Scale-up operations of CuSOB4B-NaB2BSOB4B electrolytic ...

African Journals Online (AJOL)

Scale-up techniques were established for an Inclined Cathode Electrochemical Cell (ICEC) for the removal of copper ions from a CuSOB4B-NaB2BSOB4B solution at reduced operation power consumption. The scale-up relationshi-ps were derived and applied in conjunction with scale-up factors. With a scale-up factor of 2, ...

A modified scaled variable reduced coordinate (SVRC)-quantitative structure property relationship (QSPR) model for predicting liquid viscosity of pure organic compounds

Energy Technology Data Exchange (ETDEWEB)

Lee, Seongmin; Park, Kiho; Yang, Dae Ryook [Korea University, Seoul (Korea, Republic of); Kwon, Yunkyung; Park, Taeyun [ChemEssen Inc., Seoul (Korea, Republic of)

2017-10-15

Liquid viscosity is an important physical property utilized in engineering designs for transportation and processing of fluids. However, the measurement of liquid viscosity is not always easy when the materials have toxicity and instability. In this study, a modified scaled variable reduced coordinate (SVRC)-quantitative structure property relationship (QSPR) model is suggested and analyzed in terms of its performance of prediction for liquid viscosity compared to the conventional SVRC-QSPR model and the other methods. The modification was conducted by changing the initial point from triple point to ambient temperature (293 K), and assuming that the liquid viscosity at critical temperature is 0 cP. The results reveal that the prediction performance of the modified SVRC-QSPR model is comparable to the other methods as showing 7.90% of mean absolute percentage error (MAPE) and 0.9838 of R{sup 2}. In terms of both the number of components and the performance of prediction, the modified SVRC-QSPR model is superior to the conventional SVRC-QSPR model. Also, the applicability of the model is improved since the condition of the end points of the modified model is not so restrictive as the conventional SVRC-QSPR model.

A modified scaled variable reduced coordinate (SVRC)-quantitative structure property relationship (QSPR) model for predicting liquid viscosity of pure organic compounds

International Nuclear Information System (INIS)

Lee, Seongmin; Park, Kiho; Yang, Dae Ryook; Kwon, Yunkyung; Park, Taeyun

2017-01-01

Liquid viscosity is an important physical property utilized in engineering designs for transportation and processing of fluids. However, the measurement of liquid viscosity is not always easy when the materials have toxicity and instability. In this study, a modified scaled variable reduced coordinate (SVRC)-quantitative structure property relationship (QSPR) model is suggested and analyzed in terms of its performance of prediction for liquid viscosity compared to the conventional SVRC-QSPR model and the other methods. The modification was conducted by changing the initial point from triple point to ambient temperature (293 K), and assuming that the liquid viscosity at critical temperature is 0 cP. The results reveal that the prediction performance of the modified SVRC-QSPR model is comparable to the other methods as showing 7.90% of mean absolute percentage error (MAPE) and 0.9838 of R 2 . In terms of both the number of components and the performance of prediction, the modified SVRC-QSPR model is superior to the conventional SVRC-QSPR model. Also, the applicability of the model is improved since the condition of the end points of the modified model is not so restrictive as the conventional SVRC-QSPR model.

Relationships between aquatic vegetation and water turbidity: A field survey across seasons and spatial scales.

Science.gov (United States)

Austin, Åsa N; Hansen, Joakim P; Donadi, Serena; Eklöf, Johan S

2017-01-01

Field surveys often show that high water turbidity limits cover of aquatic vegetation, while many small-scale experiments show that vegetation can reduce turbidity by decreasing water flow, stabilizing sediments, and competing with phytoplankton for nutrients. Here we bridged these two views by exploring the direction and strength of causal relationships between aquatic vegetation and turbidity across seasons (spring and late summer) and spatial scales (local and regional), using causal modeling based on data from a field survey along the central Swedish Baltic Sea coast. The two best-fitting regional-scale models both suggested that in spring, high cover of vegetation reduces water turbidity. In summer, the relationships differed between the two models; in the first model high vegetation cover reduced turbidity; while in the second model reduction of summer turbidity by high vegetation cover in spring had a positive effect on summer vegetation which suggests a positive feedback of vegetation on itself. Nitrogen load had a positive effect on turbidity in both seasons, which was comparable in strength to the effect of vegetation on turbidity. To assess whether the effect of vegetation was primarily caused by sediment stabilization or a reduction of phytoplankton, we also tested models where turbidity was replaced by phytoplankton fluorescence or sediment-driven turbidity. The best-fitting regional-scale models suggested that high sediment-driven turbidity in spring reduces vegetation cover in summer, which in turn has a negative effect on sediment-driven turbidity in summer, indicating a potential positive feedback of sediment-driven turbidity on itself. Using data at the local scale, few relationships were significant, likely due to the influence of unmeasured variables and/or spatial heterogeneity. In summary, causal modeling based on data from a large-scale field survey suggested that aquatic vegetation can reduce turbidity at regional scales, and that high

Relationships between aquatic vegetation and water turbidity: A field survey across seasons and spatial scales.

Directory of Open Access Journals (Sweden)

Åsa N Austin

Full Text Available Field surveys often show that high water turbidity limits cover of aquatic vegetation, while many small-scale experiments show that vegetation can reduce turbidity by decreasing water flow, stabilizing sediments, and competing with phytoplankton for nutrients. Here we bridged these two views by exploring the direction and strength of causal relationships between aquatic vegetation and turbidity across seasons (spring and late summer and spatial scales (local and regional, using causal modeling based on data from a field survey along the central Swedish Baltic Sea coast. The two best-fitting regional-scale models both suggested that in spring, high cover of vegetation reduces water turbidity. In summer, the relationships differed between the two models; in the first model high vegetation cover reduced turbidity; while in the second model reduction of summer turbidity by high vegetation cover in spring had a positive effect on summer vegetation which suggests a positive feedback of vegetation on itself. Nitrogen load had a positive effect on turbidity in both seasons, which was comparable in strength to the effect of vegetation on turbidity. To assess whether the effect of vegetation was primarily caused by sediment stabilization or a reduction of phytoplankton, we also tested models where turbidity was replaced by phytoplankton fluorescence or sediment-driven turbidity. The best-fitting regional-scale models suggested that high sediment-driven turbidity in spring reduces vegetation cover in summer, which in turn has a negative effect on sediment-driven turbidity in summer, indicating a potential positive feedback of sediment-driven turbidity on itself. Using data at the local scale, few relationships were significant, likely due to the influence of unmeasured variables and/or spatial heterogeneity. In summary, causal modeling based on data from a large-scale field survey suggested that aquatic vegetation can reduce turbidity at regional scales

Item reduction and psychometric validation of the Oily Skin Self Assessment Scale (OSSAS) and the Oily Skin Impact Scale (OSIS).

Science.gov (United States)

Arbuckle, Robert; Clark, Marci; Harness, Jane; Bonner, Nicola; Scott, Jane; Draelos, Zoe; Rizer, Ronald; Yeh, Yating; Copley-Merriman, Kati

2009-01-01

Developed using focus groups, the Oily Skin Self Assessment Scale (OSSAS) and Oily Skin Impact Scale (OSIS) are patient-reported outcome measures of oily facial skin. The aim of this study was to finalize the item-scale structure of the instruments and perform psychometric validation in adults with self-reported oily facial skin. The OSSAS and OSIS were administered to 202 adult subjects with oily facial skin in the United States. A subgroup of 152 subjects returned, 4 to 10 days later, for test–retest reliability evaluation. Of the 202 participants, 72.8% were female; 64.4% had self-reported nonsevere acne. Item reduction resulted in a 14-item OSSAS with Sensation (five items), Tactile (four items) and Visual (four items) domains, a single blotting item, and an overall oiliness item. The OSIS was reduced to two three-item domains assessing Annoyance and Self-Image. Confirmatory factor analysis supported the construct validity of the final item-scale structures. The OSSAS and OSIS scales had acceptable item convergent validity (item-scale correlations >0.40) and floor and ceiling effects (skin severity (P skin (P skin), as assessments of self-reported oily facial skin severity and its emotional impact, respectively.

Impact of the heavy-quark matching scales in PDF fits

Energy Technology Data Exchange (ETDEWEB)

Bertone, V. [VU University, Department of Physics and Astronomy, Amsterdam (Netherlands); Nikhef Theory Group Science Park 105, Amsterdam (Netherlands); Britzger, D.; Geiser, A.; Glazov, A.; Zenaiev, O. [DESY, Hamburg (Germany); Camarda, S. [CERN, Geneva (Switzerland); Cooper-Sarkar, A.; Giuli, F. [University of Oxford (United Kingdom); Godat, E.; Lyonnet, F.; Olness, F. [SMU Physics, Dallas, TX (United States); Kusina, A. [Universite Grenoble Alpes, CNRS/IN2P3, Laboratoire de Physique Subatomique et de Cosmologie, Grenoble (France); Polish Academy of Sciences, Institute of Nuclear Physics, Krakow (Poland); Luszczak, A. [T. Kosciuszko Cracow University of Technology, Krakow (Poland); Placakyte, R. [Universitaet Hamburg, Institut fuer Theoretische Physik, Hamburg (Germany); Radescu, V. [DESY, Hamburg (Germany); CERN, Geneva (Switzerland); Schienbein, I. [Universite Grenoble Alpes, CNRS/IN2P3, Laboratoire de Physique Subatomique et de Cosmologie, Grenoble (France); Collaboration: The xFitter Developers' Team

2017-12-15

We investigate the impact of displaced heavy-quark matching scales in a global fit. The heavy-quark matching scale μ{sub m} determines at which energy scale μ the QCD theory transitions from N{sub F} to N{sub F} + 1 in the variable flavor number scheme (VFNS) for the evolution of the parton distribution functions (PDFs) and strong coupling α{sub S}(μ). We study the variation of the matching scales, and their impact on a global PDF fit of the combined HERA data. As the choice of the matching scale μ{sub m} effectively is a choice of scheme, this represents a theoretical uncertainty; ideally, we would like to see minimal dependence on this parameter. For the transition across the charm quark (from N{sub F} = 3 to 4), we find a large μ{sub m} = μ{sub c} dependence of the global fit χ{sup 2} at NLO, but this is significantly reduced at NNLO. For the transition across the bottom quark (from N{sub F} = 4 to 5), we have a reduced μ{sub m} = μ{sub b} dependence of the χ{sup 2} at both NLO and NNLO as compared to the charm. This feature is now implemented in xFitter 2.0.0, an open source QCD fit framework. (orig.)

Can stroke patients use visual analogue scales?

Science.gov (United States)

Price, C I; Curless, R H; Rodgers, H

1999-07-01

Visual analogue scales (VAS) have been used for the subjective measurement of mood, pain, and health status after stroke. In this study we investigated how stroke-related impairments could alter the ability of subjects to answer accurately. Consent was obtained from 96 subjects with a clinical stroke (mean age, 72.5 years; 50 men) and 48 control subjects without cerebrovascular disease (mean age, 71.5 years; 29 men). Patients with reduced conscious level or severe dysphasia were excluded. Subjects were asked to rate the tightness that they could feel on the (unaffected) upper arm after 3 low-pressure inflations with a standard sphygmomanometer cuff, which followed a predetermined sequence (20 mm Hg, 40 mm Hg, 0 mm Hg). Immediately after each change, they rated the perceived tightness on 5 scales presented in a random order: 4-point rating scale (none, mild, moderate, severe), 0 to 10 numerical rating scale, mechanical VAS, horizontal VAS, and vertical VAS. Standard tests recorded deficits in language, cognition, and visuospatial awareness. Inability to complete scales with the correct pattern was associated with any stroke (P<0.001). There was a significant association between success using scales and milder clinical stroke subtype (P<0.01). Within the stroke group, logistic regression analysis identified significant associations (P<0.05) between impairments (cognitive and visuospatial) and inability to complete individual scales correctly. Many patients after a stroke are unable to successfully complete self-report measurement scales, including VAS.

A hierarchical approach to reducing communication in parallel graph algorithms

KAUST Repository

Harshvardhan,

2015-01-01

Large-scale graph computing has become critical due to the ever-increasing size of data. However, distributed graph computations are limited in their scalability and performance due to the heavy communication inherent in such computations. This is exacerbated in scale-free networks, such as social and web graphs, which contain hub vertices that have large degrees and therefore send a large number of messages over the network. Furthermore, many graph algorithms and computations send the same data to each of the neighbors of a vertex. Our proposed approach recognizes this, and reduces communication performed by the algorithm without change to user-code, through a hierarchical machine model imposed upon the input graph. The hierarchical model takes advantage of locale information of the neighboring vertices to reduce communication, both in message volume and total number of bytes sent. It is also able to better exploit the machine hierarchy to further reduce the communication costs, by aggregating traffic between different levels of the machine hierarchy. Results of an implementation in the STAPL GL shows improved scalability and performance over the traditional level-synchronous approach, with 2.5 × - 8× improvement for a variety of graph algorithms at 12, 000+ cores.

Genetic Analysis of Reduced γ-Tocopherol Content in Ethiopian Mustard Seeds.

Science.gov (United States)

García-Navarro, Elena; Fernández-Martínez, José M; Pérez-Vich, Begoña; Velasco, Leonardo

2016-01-01

Ethiopian mustard (Brassica carinata A. Braun) line BCT-6, with reduced γ-tocopherol content in the seeds, has been previously developed. The objective of this research was to conduct a genetic analysis of seed tocopherols in this line. BCT-6 was crossed with the conventional line C-101 and the F1, F2, and BC plant generations were analyzed. Generation mean analysis using individual scaling tests indicated that reduced γ-tocopherol content fitted an additive-dominant genetic model with predominance of additive effects and absence of epistatic interactions. This was confirmed through a joint scaling test and additional testing of the goodness of fit of the model. Conversely, epistatic interactions were identified for total tocopherol content. Estimation of the minimum number of genes suggested that both γ- and total tocopherol content may be controlled by two genes. A positive correlation between total tocopherol content and the proportion of γ-tocopherol was identified in the F2 generation. Additional research on the feasibility of developing germplasm with high tocopherol content and reduced concentration of γ-tocopherol is required.

Genetic Analysis of Reduced γ-Tocopherol Content in Ethiopian Mustard Seeds

Directory of Open Access Journals (Sweden)

Elena García-Navarro

2016-01-01

Full Text Available Ethiopian mustard (Brassica carinata A. Braun line BCT-6, with reduced γ-tocopherol content in the seeds, has been previously developed. The objective of this research was to conduct a genetic analysis of seed tocopherols in this line. BCT-6 was crossed with the conventional line C-101 and the F1, F2, and BC plant generations were analyzed. Generation mean analysis using individual scaling tests indicated that reduced γ-tocopherol content fitted an additive-dominant genetic model with predominance of additive effects and absence of epistatic interactions. This was confirmed through a joint scaling test and additional testing of the goodness of fit of the model. Conversely, epistatic interactions were identified for total tocopherol content. Estimation of the minimum number of genes suggested that both γ- and total tocopherol content may be controlled by two genes. A positive correlation between total tocopherol content and the proportion of γ-tocopherol was identified in the F2 generation. Additional research on the feasibility of developing germplasm with high tocopherol content and reduced concentration of γ-tocopherol is required.

Reducing Disparity in Radio-Isotopic and Astrochronology-Based Time Scales of the Late Eocene and Oligocene

NARCIS (Netherlands)

Sahy, Diana; Condon, Daniel J.; Hilgen, Frederik J.|info:eu-repo/dai/nl/102639876; Kuiper, Klaudia F.|info:eu-repo/dai/nl/258125772

2017-01-01

A significant discrepancy of up to 0.6 Myr exists between radio-isotopically calibrated and astronomically tuned time scales of the late Eocene-Oligocene. We explore the possible causes of this discrepancy through the acquisition of “high-precision” 206Pb/238U dating of zircons from 11 volcanic ash

Testing a two-scale focused conservation strategy for reducing phosphorus and sediment loads from agricultural watersheds

Science.gov (United States)

Carvin, Rebecca; Good, Laura W.; Fitzpatrick, Faith A.; Diehl, Curt; Songer, Katherine; Meyer, Kimberly J.; Panuska, John C.; Richter, Steve; Whalley, Kyle

2018-01-01

This study tested a focused strategy for reducing phosphorus (P) and sediment loads in agricultural streams. The strategy involved selecting small watersheds identified as likely to respond relatively quickly, and then focusing conservation practices on high-contributing fields within those watersheds. Two 5,000 ha (12,360 ac) watersheds in the Driftless Area of south central Wisconsin, previously ranked in the top 6% of similarly sized Wisconsin watersheds for expected responsiveness to conservation efforts to reduce high P and sediment loads, were chosen for the study. The stream outlets from both watersheds were monitored from October of 2006 through September of 2016 for streamflow and concentrations of sediment, total P, and, beginning in October of 2009, total dissolved P. Fields and pastures having the highest potential P delivery to the streams in each watershed were identified using the Wisconsin P Index (Good et al. 2012). After three years of baseline monitoring (2006 to 2009), farmers implemented both field- and farm-based conservation practices in one watershed (treatment) as a means to reduce sediment and P inputs to the stream from the highest contributing areas, whereas there were no out-of-the-ordinary conservation efforts in the second watershed (control). Implementation occurred primarily in 2011 and 2012. In the four years following implementation of conservation practices (2013 through 2016), there was a statistically significant reduction in storm-event suspended sediment loads in the treatment watershed compared to the control watershed when the ground was not frozen (p = 0.047). While there was an apparent reduction in year-round suspended sediment event loads, it was not statistically significant at the 95% confidence level (p = 0.15). Total P loads were significantly reduced for runoff events (p < 0.01) with a median reduction of 50%. Total P and total dissolved P concentrations for low-flow conditions were also significantly reduced (p

Scaling Phenomena in Desalination With Multi Stage Flash Distillation (MSF)

International Nuclear Information System (INIS)

Siti-Alimah

2006-01-01

Assessment of scaling phenomena in MSF desalination has been carried out. Scale is one of predominantly problem in multi stage flash (MSF) desalination installation. The main types of scale in MSF are carbonate calcium (CaCO 3 ), hydroxide magnesium (Mg(OH) 2 ) and sulphate calcium (CaSO 4 ). CaCO 3 and Mg(OH) 2 scales result from the thermal decomposition of bicarbonate ion, however sulphate calcium scale result from reaction of calcium ion and sulfate ion present in seawater. The rate of formation scale in seawater depends on temperature, pH, concentration of ions, supersaturated solution, nucleation and diffusion. The scales in MSF installation can occur inside heat exchanger tube, brine heater tubes, water boxes, on the face of tube sheets and demister pads. Scaling reduces effectiveness (production and heat consumption) of the process. To avoid the reductions in performance caused by scale precipitation, desalination units employ scale control. To control this scaling problem, the following methods can be used; acid, additive (scale inhibitors) and mechanical cleaning. Stoichiometric amounts of acid must be added to seawater, because addition excess of acid will increase corrosion problems. Using of scale inhibitors as polyphosphates, phosphonates, polyacrylates and poly maleates have advantage and disadvantage. (author)

Economy of scale: third partner strengthens a keystone ant-plant mutualism.

Science.gov (United States)

Prior, Kirsten M; Palmer, Todd M

2018-02-01

While foundation species can stabilize ecosystems at landscape scales, their ability to persist is often underlain by keystone interactions occurring at smaller scales. Acacia drepanolobium is a foundation tree, comprising >95% of woody cover in East African black-cotton savanna ecosystems. Its dominance is underlain by a keystone mutualistic interaction with several symbiotic ant species in which it provides housing (swollen thorns) and carbohydrate-rich nectar from extra-floral nectaries (EFN). In return, it gains protection from catastrophic damage from mega-herbivores. Crematogaster mimosae is the ecologically dominant symbiotic ant in this system, also providing the highest protection services. In addition to tending EFN, C. mimosae tend scale insects for carbohydrate-rich honeydew. We investigated the role of scale insects in this specialized ant-plant interaction. Specifically, does this putatively redundant third partner strengthen the ant-plant mutualism by making the ant a better protector of the tree? Or does it weaken the mutualism by being costly to the tree while providing no additional benefit to the ant-plant mutualism? We coupled observational surveys with two scale-manipulation experiments and found evidence that this third partner strengthens the ant-plant mutualism. Trees with scale insects experimentally removed experienced a 2.5X increase in elephant damage compared to trees with scale insects present over 10 months. Reduced protection was driven by scale removal causing a decrease in ant colony size and per capita baseline activity and defensive behavior. We also found that ants increased scale-tending and the density of scale insects on trees when EFN were experimentally reduced. Thus, in this system, scale insects and EFN are likely complementary, rather than redundant, resources with scale insects benefitting ants when EFN production is low (such as during annual dry periods in this semi-arid ecosystem). This study reveals that a third

Simultaneous approximation in scales of Banach spaces

International Nuclear Information System (INIS)

Bramble, J.H.; Scott, R.

1978-01-01

The problem of verifying optimal approximation simultaneously in different norms in a Banach scale is reduced to verification of optimal approximation in the highest order norm. The basic tool used is the Banach space interpolation method developed by Lions and Peetre. Applications are given to several problems arising in the theory of finite element methods

What is at stake in multi-scale approaches

International Nuclear Information System (INIS)

Jamet, Didier

2008-01-01

Full text of publication follows: Multi-scale approaches amount to analyzing physical phenomena at small space and time scales in order to model their effects at larger scales. This approach is very general in physics and engineering; one of the best examples of success of this approach is certainly statistical physics that allows to recover classical thermodynamics and to determine the limits of application of classical thermodynamics. Getting access to small scale information aims at reducing the models' uncertainty but it has a cost: fine scale models may be more complex than larger scale models and their resolution may require the development of specific and possibly expensive methods, numerical simulation techniques and experiments. For instance, in applications related to nuclear engineering, the application of computational fluid dynamics instead of cruder models is a formidable engineering challenge because it requires resorting to high performance computing. Likewise, in two-phase flow modeling, the techniques of direct numerical simulation, where all the interfaces are tracked individually and where all turbulence scales are captured, are getting mature enough to be considered for averaged modeling purposes. However, resolving small scale problems is a necessary step but it is not sufficient in a multi-scale approach. An important modeling challenge is to determine how to treat small scale data in order to get relevant information for larger scale models. For some applications, such as single-phase turbulence or transfers in porous media, this up-scaling approach is known and is now used rather routinely. However, in two-phase flow modeling, the up-scaling approach is not as mature and specific issues must be addressed that raise fundamental questions. This will be discussed and illustrated. (author)

A Guide to Bundling Small-scale CDM Projects

International Nuclear Information System (INIS)

Mariyappan, J.; Bhardwaj, N.; De Coninck, H.; Van der Linden, N.

2005-07-01

Small-scale renewable energy and energy efficiency projects that fit the development needs of many developing countries, can potentially be supported via the Clean Development Mechanism (CDM), one of the Kyoto Protocol's flexible mechanisms for tackling climate change. However, there is concern that due to high transaction costs, as well as many existing barriers, very few investments will be made in small-scale projects, which are often the most suitable development option in countries such as India. In view of this, the 'bundling' together of appropriate small-scale projects on a regional basis has been proposed as a way in which funding can be leveraged from international sources and transaction costs reduced. IT Power, IT Power India and the Energy research Centre of the Netherlands (ECN) are carrying out a 2-year project to establish the capacity within India to enable individual small scale projects to be bundled as a single CDM project. Overall objectives are to develop the necessary institutional capabilities to formulate and implement small scale CDM projects in India; to provide a guide on how to bundle small scale projects under the CDM in developing countries; and to raise the awareness of the potential for investment in small scale energy projects which can gain funding through the CDM

Final Report: Large-Scale Optimization for Bayesian Inference in Complex Systems

Energy Technology Data Exchange (ETDEWEB)

Ghattas, Omar [The University of Texas at Austin

2013-10-15

The SAGUARO (Scalable Algorithms for Groundwater Uncertainty Analysis and Robust Optimiza- tion) Project focuses on the development of scalable numerical algorithms for large-scale Bayesian inversion in complex systems that capitalize on advances in large-scale simulation-based optimiza- tion and inversion methods. Our research is directed in three complementary areas: efficient approximations of the Hessian operator, reductions in complexity of forward simulations via stochastic spectral approximations and model reduction, and employing large-scale optimization concepts to accelerate sampling. Our efforts are integrated in the context of a challenging testbed problem that considers subsurface reacting flow and transport. The MIT component of the SAGUARO Project addresses the intractability of conventional sampling methods for large-scale statistical inverse problems by devising reduced-order models that are faithful to the full-order model over a wide range of parameter values; sampling then employs the reduced model rather than the full model, resulting in very large computational savings. Results indicate little effect on the computed posterior distribution. On the other hand, in the Texas-Georgia Tech component of the project, we retain the full-order model, but exploit inverse problem structure (adjoint-based gradients and partial Hessian information of the parameter-to- observation map) to implicitly extract lower dimensional information on the posterior distribution; this greatly speeds up sampling methods, so that fewer sampling points are needed. We can think of these two approaches as "reduce then sample" and "sample then reduce." In fact, these two approaches are complementary, and can be used in conjunction with each other. Moreover, they both exploit deterministic inverse problem structure, in the form of adjoint-based gradient and Hessian information of the underlying parameter-to-observation map, to achieve their speedups.

Spatial scale separation in regional climate modelling

Energy Technology Data Exchange (ETDEWEB)

Feser, F.

2005-07-01

In this thesis the concept of scale separation is introduced as a tool for first improving regional climate model simulations and, secondly, to explicitly detect and describe the added value obtained by regional modelling. The basic idea behind this is that global and regional climate models have their best performance at different spatial scales. Therefore the regional model should not alter the global model's results at large scales. The for this purpose designed concept of nudging of large scales controls the large scales within the regional model domain and keeps them close to the global forcing model whereby the regional scales are left unchanged. For ensemble simulations nudging of large scales strongly reduces the divergence of the different simulations compared to the standard approach ensemble that occasionally shows large differences for the individual realisations. For climate hindcasts this method leads to results which are on average closer to observed states than the standard approach. Also the analysis of the regional climate model simulation can be improved by separating the results into different spatial domains. This was done by developing and applying digital filters that perform the scale separation effectively without great computational effort. The separation of the results into different spatial scales simplifies model validation and process studies. The search for 'added value' can be conducted on the spatial scales the regional climate model was designed for giving clearer results than by analysing unfiltered meteorological fields. To examine the skill of the different simulations pattern correlation coefficients were calculated between the global reanalyses, the regional climate model simulation and, as a reference, of an operational regional weather analysis. The regional climate model simulation driven with large-scale constraints achieved a high increase in similarity to the operational analyses for medium-scale 2 meter

Comparing short forms of the Social Interaction Anxiety Scale and the Social Phobia Scale.

Science.gov (United States)

Carleton, R Nicholas; Thibodeau, Michel A; Weeks, Justin W; Teale Sapach, Michelle J N; McEvoy, Peter M; Horswill, Samantha C; Heimberg, Richard G

2014-12-01

The Social Interaction Anxiety Scale (SIAS) and the Social Phobia Scale (SPS; Mattick & Clarke, 1998) are companion scales developed to measure anxiety in social interaction and performance situations, respectively. The measures have strong discriminant and convergent validity; however, their factor structures remain debated, and furthermore, the combined administration length (i.e., 39 items) can be prohibitive for some settings. There have been 4 attempts to assess the factor structures of the scales and reduce the item content: the 14-item Social Interaction Phobia Scale (SIPS; Carleton et al., 2009), the 12-item SIAS-6/SPS-6 (Peters, Sunderland, Andrews, Rapee, & Mattick, 2012), the 21-item abbreviated SIAS/SPS (ASIAS/ASPS; Kupper & Denollet, 2012), and the 12-item Readability SIAS and SPS (RSIAS/RSPS; Fergus, Valentiner, McGrath, Gier-Lonsway, & Kim, 2012). The current study compared the short forms on (a) factor structure, (b) ability to distinguish between clinical and non-clinical populations, (c) sensitivity to change following therapy, and (d) convergent validity with related measures. Participants included 3,607 undergraduate students (55% women) and 283 patients with social anxiety disorder (43% women). Results of confirmatory factor analyses, sensitivity analyses, and correlation analyses support the robust utility of items in the SIPS and the SPS-6 and SIAS-6 relative to the other short forms; furthermore, the SIPS and the SPS-6 and SIAS-6 were also supported by convergent validity analyses within the undergraduate sample. The RSIAS/RSPS and the ASIAS/ASPS were least supported, based on the current results and the principle of parsimony. Accordingly, researchers and clinicians should consider carefully which of the short forms will best suit their needs. (c) 2014 APA, all rights reserved.

General Biology and Current Management Approaches of Soft Scale Pests (Hemiptera: Coccidae).

Science.gov (United States)

Camacho, Ernesto Robayo; Chong, Juang-Horng

We summarize the economic importance, biology, and management of soft scales, focusing on pests of agricultural, horticultural, and silvicultural crops in outdoor production systems and urban landscapes. We also provide summaries on voltinism, crawler emergence timing, and predictive models for crawler emergence to assist in developing soft scale management programs. Phloem-feeding soft scale pests cause direct (e.g., injuries to plant tissues and removal of nutrients) and indirect damage (e.g., reduction in photosynthesis and aesthetic value by honeydew and sooty mold). Variations in life cycle, reproduction, fecundity, and behavior exist among congenerics due to host, environmental, climatic, and geographical variations. Sampling of soft scale pests involves sighting the insects or their damage, and assessing their abundance. Crawlers of most univoltine species emerge in the spring and the summer. Degree-day models and plant phenological indicators help determine the initiation of sampling and treatment against crawlers (the life stage most vulnerable to contact insecticides). The efficacy of cultural management tactics, such as fertilization, pruning, and irrigation, in reducing soft scale abundance is poorly documented. A large number of parasitoids and predators attack soft scale populations in the field; therefore, natural enemy conservation by using selective insecticides is important. Systemic insecticides provide greater flexibility in application method and timing, and have longer residual longevity than contact insecticides. Application timing of contact insecticides that coincides with crawler emergence is most effective in reducing soft scale abundance.

Temporal scaling in information propagation

Science.gov (United States)

Huang, Junming; Li, Chao; Wang, Wen-Qiang; Shen, Hua-Wei; Li, Guojie; Cheng, Xue-Qi

2014-06-01

For the study of information propagation, one fundamental problem is uncovering universal laws governing the dynamics of information propagation. This problem, from the microscopic perspective, is formulated as estimating the propagation probability that a piece of information propagates from one individual to another. Such a propagation probability generally depends on two major classes of factors: the intrinsic attractiveness of information and the interactions between individuals. Despite the fact that the temporal effect of attractiveness is widely studied, temporal laws underlying individual interactions remain unclear, causing inaccurate prediction of information propagation on evolving social networks. In this report, we empirically study the dynamics of information propagation, using the dataset from a population-scale social media website. We discover a temporal scaling in information propagation: the probability a message propagates between two individuals decays with the length of time latency since their latest interaction, obeying a power-law rule. Leveraging the scaling law, we further propose a temporal model to estimate future propagation probabilities between individuals, reducing the error rate of information propagation prediction from 6.7% to 2.6% and improving viral marketing with 9.7% incremental customers.

Large-Scale, Parallel, Multi-Sensor Data Fusion in the Cloud

Science.gov (United States)

Wilson, B. D.; Manipon, G.; Hua, H.

2012-12-01

NASA's Earth Observing System (EOS) is an ambitious facility for studying global climate change. The mandate now is to combine measurements from the instruments on the "A-Train" platforms (AIRS, AMSR-E, MODIS, MISR, MLS, and CloudSat) and other Earth probes to enable large-scale studies of climate change over periods of years to decades. However, moving from predominantly single-instrument studies to a multi-sensor, measurement-based model for long-duration analysis of important climate variables presents serious challenges for large-scale data mining and data fusion. For example, one might want to compare temperature and water vapor retrievals from one instrument (AIRS) to another instrument (MODIS), and to a model (ECMWF), stratify the comparisons using a classification of the "cloud scenes" from CloudSat, and repeat the entire analysis over years of AIRS data. To perform such an analysis, one must discover & access multiple datasets from remote sites, find the space/time "matchups" between instruments swaths and model grids, understand the quality flags and uncertainties for retrieved physical variables, assemble merged datasets, and compute fused products for further scientific and statistical analysis. To efficiently assemble such decade-scale datasets in a timely manner, we are utilizing Elastic Computing in the Cloud and parallel map/reduce-based algorithms. "SciReduce" is a Hadoop-like parallel analysis system, programmed in parallel python, that is designed from the ground up for Earth science. SciReduce executes inside VMWare images and scales to any number of nodes in the Cloud. Unlike Hadoop, in which simple tuples (keys & values) are passed between the map and reduce functions, SciReduce operates on bundles of named numeric arrays, which can be passed in memory or serialized to disk in netCDF4 or HDF5. Thus, SciReduce uses the native datatypes (geolocated grids, swaths, and points) that geo-scientists are familiar with. We are deploying within SciReduce

Simple scaling for faster tracking simulation in accelerator multiparticle dynamics

International Nuclear Information System (INIS)

MacLachlan, J.A.

2001-01-01

Macroparticle tracking is a direct and attractive approach to following the evolution of a phase space distribution. When the particles interact through short range wake fields or when inter-particle force is included, calculations of this kind require a large number of macroparticles. It is possible to reduce both the number of macroparticles required and the number of tracking steps per unit simulated time by employing a simple scaling which can be inferred directly from the single-particle equations of motion. In many cases of practical importance the speed of calculation improves with the fourth power of the scaling constant. Scaling has been implemented in an existing longitudinal tracking code; early experience supports the concept and promises major time savings. Limitations on the scaling are discussed

Alpine Ecohydrology Across Scales: Propagating Fine-scale Heterogeneity to the Catchment and Beyond

Science.gov (United States)

Mastrotheodoros, T.; Pappas, C.; Molnar, P.; Burlando, P.; Hadjidoukas, P.; Fatichi, S.

2017-12-01

In mountainous ecosystems, complex topography and landscape heterogeneity govern ecohydrological states and fluxes. Here, we investigate topographic controls on water, energy and carbon fluxes across different climatic regimes and vegetation types representative of the European Alps. We use an ecohydrological model to perform fine-scale numerical experiments on a synthetic domain that comprises a symmetric mountain with eight catchments draining along the cardinal and intercardinal directions. Distributed meteorological model input variables are generated using observations from Switzerland. The model computes the incoming solar radiation based on the local topography. We implement a multivariate statistical framework to disentangle the impact of landscape heterogeneity (i.e., elevation, aspect, flow contributing area, vegetation type) on the simulated water, carbon, and energy dynamics. This allows us to identify the sensitivities of several ecohydrological variables (including leaf area index, evapotranspiration, snow-cover and net primary productivity) to topographic and meteorological inputs at different spatial and temporal scales. We also use an alpine catchment as a real case study to investigate how the natural variability of soil and land cover affects the idealized relationships that arise from the synthetic domain. In accordance with previous studies, our analysis shows a complex pattern of vegetation response to radiation. We find also different patterns of ecosystem sensitivity to topography-driven heterogeneity depending on the hydrological regime (i.e., wet vs. dry conditions). Our results suggest that topography-driven variability in ecohydrological variables (e.g. transpiration) at the fine spatial scale can exceed 50%, but it is substantially reduced ( 5%) when integrated at the catchment scale.

On the need for a time- and location-dependent estimation of the NDSI threshold value for reducing existing uncertainties in snow cover maps at different scales

Science.gov (United States)

Härer, Stefan; Bernhardt, Matthias; Siebers, Matthias; Schulz, Karsten

2018-05-01

Knowledge of current snow cover extent is essential for characterizing energy and moisture fluxes at the Earth's surface. The snow-covered area (SCA) is often estimated by using optical satellite information in combination with the normalized-difference snow index (NDSI). The NDSI thereby uses a threshold for the definition if a satellite pixel is assumed to be snow covered or snow free. The spatiotemporal representativeness of the standard threshold of 0.4 is however questionable at the local scale. Here, we use local snow cover maps derived from ground-based photography to continuously calibrate the NDSI threshold values (NDSIthr) of Landsat satellite images at two European mountain sites of the period from 2010 to 2015. The Research Catchment Zugspitzplatt (RCZ, Germany) and Vernagtferner area (VF, Austria) are both located within a single Landsat scene. Nevertheless, the long-term analysis of the NDSIthr demonstrated that the NDSIthr at these sites are not correlated (r = 0.17) and different than the standard threshold of 0.4. For further comparison, a dynamic and locally optimized NDSI threshold was used as well as another locally optimized literature threshold value (0.7). It was shown that large uncertainties in the prediction of the SCA of up to 24.1 % exist in satellite snow cover maps in cases where the standard threshold of 0.4 is used, but a newly developed calibrated quadratic polynomial model which accounts for seasonal threshold dynamics can reduce this error. The model minimizes the SCA uncertainties at the calibration site VF by 50 % in the evaluation period and was also able to improve the results at RCZ in a significant way. Additionally, a scaling experiment shows that the positive effect of a locally adapted threshold diminishes using a pixel size of 500 m or larger, underlining the general applicability of the standard threshold at larger scales.

Scale and scaling in agronomy and environmental sciences

Science.gov (United States)

Scale is of paramount importance in environmental studies, engineering, and design. The unique course covers the following topics: scale and scaling, methods and theories, scaling in soils and other porous media, scaling in plants and crops; scaling in landscapes and watersheds, and scaling in agro...

Current scaling of radiated power for 40-mm diameter single wire arrays on Z

Science.gov (United States)

Nash, T. J.; Cuneo, M. E.; Spielman, R. B.; Chandler, G. A.; Leeper, R. J.; Seaman, J. F.; McGurn, J.; Lazier, S.; Torres, J.; Jobe, D.; Gilliland, T.; Nielsen, D.; Hawn, R.; Bailey, J. E.; Lake, P.; Carlson, A. L.; Seamen, H.; Moore, T.; Smelser, R.; Pyle, J.; Wagoner, T. C.; LePell, P. D.; Deeney, C.; Douglas, M. R.; McDaniel, D.; Struve, K.; Mazarakis, M.; Stygar, W. A.

2004-11-01

In order to estimate the radiated power that can be expected from the next-generation Z-pinch driver such as ZR at 28 MA, current-scaling experiments have been conducted on the 20 MA driver Z. We report on the current scaling of single 40 mm diameter tungsten 240 wire arrays with a fixed 110 ns implosion time. The wire diameter is decreased in proportion to the load current. Reducing the charge voltage on the Marx banks reduces the load current. On one shot, firing only three of the four levels of the Z machine further reduced the load current. The radiated energy scaled as the current squared as expected but the radiated power scaled as the current to the 3.52±0.42 power due to increased x-ray pulse width at lower current. As the current is reduced, the rise time of the x-ray pulse increases and at the lowest current value of 10.4 MA, a shoulder appears on the leading edge of the x-ray pulse. In order to determine the nature of the plasma producing the leading edge of the x-ray pulse at low currents further shots were taken with an on-axis aperture to view on-axis precursor plasma. This aperture appeared to perturb the pinch in a favorable manner such that with the aperture in place there was no leading edge to the x-ray pulses at lower currents and the radiated power scaled as the current squared ±0.75. For a full-current shot we will present x-ray images that show precursor plasma emitting on-axis 77 ns before the main x-ray burst.

Development of the Abbreviated Masculine Gender Role Stress Scale.

Science.gov (United States)

Swartout, Kevin M; Parrott, Dominic J; Cohn, Amy M; Hagman, Brett T; Gallagher, Kathryn E

2015-06-01

Data gathered from 6 independent samples (n = 1,729) that assessed men's masculine gender role stress in college and community males were aggregated used to determine the reliability and validity of an abbreviated version of the Masculine Gender Role Stress (MGRS) Scale. The 15 items with the highest item-to-total scale correlations were used to create an abbreviated MGRS Scale. Psychometric properties of each of the 15 items were examined with item response theory (IRT) analysis, using the discrimination and threshold parameters. IRT results showed that the abbreviated scale may hold promise at capturing the same amount of information as the full 40-item scale. Relative to the 40-item scale, the total score of the abbreviated MGRS Scale demonstrated comparable convergent validity using the measurement domains of masculine identity, hypermasculinity, trait anger, anger expression, and alcohol involvement. An abbreviated MGRS Scale may be recommended for use in clinical practice and research settings to reduce cost, time, and patient/participant burden. Additionally, IRT analyses identified items with higher discrimination and threshold parameters that may be used to screen for problematic gender role stress in men who may be seen in routine clinical or medical practice. (c) 2015 APA, all rights reserved).

Dental scaling and risk reduction in infective endocarditis: a nationwide population-based case-control study.

Science.gov (United States)

Chen, Su-Jung; Liu, Chia-Jen; Chao, Tze-Fan; Wang, Kang-Ling; Wang, Fu-Der; Chen, Tzeng-Ji; Chiang, Chern-En

2013-04-01

Infective endocarditis (IE) is an uncommon but potentially life-threatening disease. Poor oral hygiene has been assumed as an important risk factor for IE. We aimed to investigate whether the improvement of oral hygiene through dental scaling could reduce the risk of IE. From January 1, 2000 to December 31, 2009, a total of 736 patients with newly diagnosed IE were identified from the National Health Insurance Research Database. On the same date of enrollment, 10 patients (without IE) with matched age, sex, and underlying diseases were selected to be the control group for each study patient. The frequency of dental scaling before the enrollment was analyzed and compared between the study and the control groups. The percentages of patients who ever received dental scaling before the enrollment were higher in the control group than that in the study group. For patients who received dental scaling once in 2 years, the risk of IE can be reduced by about 15% (odds ratio, 0.845; 95% confidence interval, 0.693-1.012) with a borderline P value (P = 0.058). Moreover, the risk of IE decreased significantly among patients who received dental scaling at least once per year, with an odds ratio of 0.696 (95% confidence interval, 0.542-0.894; P = 0.005). Improvement of oral hygiene by dental scaling may reduce the risk of IE. More frequent and regular dental scaling (at least once per year) was associated with a significant decrease in IE. Copyright © 2013 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Sustainability effects of household-scale biogas in rural China

NARCIS (Netherlands)

Gosens, J.; Lu Yonglong,; He Guizhen,; Bluemling, B.; Beckers, T.A.M.

2013-01-01

Households in rural China rely heavily on low quality fuels which results in reduced quality of life and environmental degradation. This study assesses the comparative contribution of household scale biogas installations to the broad set of sustainability objectives in the Chinese biogas policy

Solid Fuel - Oxygen Fired Combustion for Production of Nodular Reduced Iron to Reduce CO2 Emissions and Improve Energy Efficiencies

Energy Technology Data Exchange (ETDEWEB)

Donald R. Fosnacht; Richard F. Kiesel; David W. Hendrickson; David J. Englund; Iwao Iwasaki; Rodney L. Bleifuss; Mathew A. Mlinar

2011-12-22

The current trend in the steel industry is an increase in iron and steel produced in electric arc furnaces (EAF) and a gradual decline in conventional steelmaking from taconite pellets in blast furnaces. In order to expand the opportunities for the existing iron ore mines beyond their blast furnace customer base, a new material is needed to satisfy the market demands of the emerging steel industry while utilizing the existing infrastructure and materials handling capabilities. This demand creates opportunity to convert iron ore or other iron bearing materials to Nodular Reduced Iron (NRI) in a recently designed Linear Hearth Furnace (LHF). NRI is a metallized iron product containing 98.5 to 96.0% iron and 2.5 to 4% C. It is essentially a scrap substitute with little impurity that can be utilized in a variety of steelmaking processes, especially the electric arc furnace. The objective of this project was to focus on reducing the greenhouse gas emissions (GHG) through reducing the energy intensity using specialized combustion systems, increasing production and the use of biomass derived carbon sources in this process. This research examined the use of a solid fuel-oxygen fired combustion system and compared the results from this system with both oxygen-fuel and air-fuel combustion systems. The solid pulverized fuels tested included various coals and a bio-coal produced from woody biomass in a specially constructed pilot scale torrefaction reactor at the Coleraine Minerals Research Laboratory (CMRL). In addition to combustion, the application of bio-coal was also tested as a means to produce a reducing atmosphere during key points in the fusion process, and as a reducing agent for ore conversion to metallic iron to capture the advantage of its inherent reduced carbon footprint. The results from this study indicate that the approaches taken can reduce both greenhouse gas emissions and the associated energy intensity with the Linear Hearth Furnace process for converting

Pilot-scale tests of HEME and HEPA dissolution process

Energy Technology Data Exchange (ETDEWEB)

Qureshi, Z.H.; Strege, D.K.

1994-06-01

A series of pilot-scale demonstration tests for the dissolution of High Efficiency Mist Eliminators (HEME`s) and High Efficiency Particulate Airfilters (HEPA) were performed on a 1/5th linear scale. These fiberglass filters are to be used in the Defense Waste Processing Facility (DWPF) to decontaminate the effluents from the off-gases generated during the feed preparation process and vitrification. When removed, these filters will be dissolved in the Decontamination Waste Treatment Tank (DWTT) using 5 wt% NaOH solution. The contaminated fiberglass is converted to an aqueous stream which will be transferred to the waste tanks. The filter metal structure will be rinsed with process water before its disposal as low-level solid waste. The pilot-scale study reported here successfully demonstrated a simple one step process using 5 wt% NaOH solution. The proposed process requires the installation of a new water spray ring with 30 nozzles. In addition to the reduced waste generated, the total process time is reduced to 48 hours only (66% saving in time). The pilot-scale tests clearly demonstrated that the dissolution process of HEMEs has two stages - chemical digestion of the filter and mechanical erosion of the digested filter. The digestion is achieved by a boiling 5 wt% caustic solutions, whereas the mechanical break down of the digested filter is successfully achieved by spraying process water on the digested filter. An alternate method of breaking down the digested filter by increased air sparging of the solution was found to be marginally successful are best. The pilot-scale tests also demonstrated that the products of dissolution are easily pumpable by a centrifugal pump.

Pilot-scale tests of HEME and HEPA dissolution process

International Nuclear Information System (INIS)

Qureshi, Z.H.; Strege, D.K.

1994-06-01

A series of pilot-scale demonstration tests for the dissolution of High Efficiency Mist Eliminators (HEME's) and High Efficiency Particulate Airfilters (HEPA) were performed on a 1/5th linear scale. These fiberglass filters are to be used in the Defense Waste Processing Facility (DWPF) to decontaminate the effluents from the off-gases generated during the feed preparation process and vitrification. When removed, these filters will be dissolved in the Decontamination Waste Treatment Tank (DWTT) using 5 wt% NaOH solution. The contaminated fiberglass is converted to an aqueous stream which will be transferred to the waste tanks. The filter metal structure will be rinsed with process water before its disposal as low-level solid waste. The pilot-scale study reported here successfully demonstrated a simple one step process using 5 wt% NaOH solution. The proposed process requires the installation of a new water spray ring with 30 nozzles. In addition to the reduced waste generated, the total process time is reduced to 48 hours only (66% saving in time). The pilot-scale tests clearly demonstrated that the dissolution process of HEMEs has two stages - chemical digestion of the filter and mechanical erosion of the digested filter. The digestion is achieved by a boiling 5 wt% caustic solutions, whereas the mechanical break down of the digested filter is successfully achieved by spraying process water on the digested filter. An alternate method of breaking down the digested filter by increased air sparging of the solution was found to be marginally successful are best. The pilot-scale tests also demonstrated that the products of dissolution are easily pumpable by a centrifugal pump

Frequency scaling of linear super-colliders

International Nuclear Information System (INIS)

Mondelli, A.; Chernin, D.; Drobot, A.; Reiser, M.; Granatstein, V.

1986-06-01

The development of electron-positron linear colliders in the TeV energy range will be facilitated by the development of high-power rf sources at frequencies above 2856 MHz. Present S-band technology, represented by the SLC, would require a length in excess of 50 km per linac to accelerate particles to energies above 1 TeV. By raising the rf driving frequency, the rf breakdown limit is increased, thereby allowing the length of the accelerators to be reduced. Currently available rf power sources set the realizable gradient limit in an rf linac at frequencies above S-band. This paper presents a model for the frequency scaling of linear colliders, with luminosity scaled in proportion to the square of the center-of-mass energy. Since wakefield effects are the dominant deleterious effect, a separate single-bunch simulation model is described which calculates the evolution of the beam bunch with specified wakefields, including the effects of using programmed phase positioning and Landau damping. The results presented here have been obtained for a SLAC structure, scaled in proportion to wavelength

Economically viable large-scale hydrogen liquefaction

Science.gov (United States)

Cardella, U.; Decker, L.; Klein, H.

2017-02-01

The liquid hydrogen demand, particularly driven by clean energy applications, will rise in the near future. As industrial large scale liquefiers will play a major role within the hydrogen supply chain, production capacity will have to increase by a multiple of today’s typical sizes. The main goal is to reduce the total cost of ownership for these plants by increasing energy efficiency with innovative and simple process designs, optimized in capital expenditure. New concepts must ensure a manageable plant complexity and flexible operability. In the phase of process development and selection, a dimensioning of key equipment for large scale liquefiers, such as turbines and compressors as well as heat exchangers, must be performed iteratively to ensure technological feasibility and maturity. Further critical aspects related to hydrogen liquefaction, e.g. fluid properties, ortho-para hydrogen conversion, and coldbox configuration, must be analysed in detail. This paper provides an overview on the approach, challenges and preliminary results in the development of efficient as well as economically viable concepts for large-scale hydrogen liquefaction.

Decision-Making and Sustainable Drainage: Design and Scale

Directory of Open Access Journals (Sweden)

Susanne Charlesworth

2016-08-01

Full Text Available Sustainable Drainage (SuDS improves water quality, reduces runoff water quantity, increases amenity and biodiversity benefits, and can also mitigate and adapt to climate change. However, an optimal solution has to be designed to be fit for purpose. Most research concentrates on individual devices, but the focus of this paper is on a full management train, showing the scale-related decision-making process in its design with reference to the city of Coventry, a local government authority in central England. It illustrates this with a large scale site-specific model which identifies the SuDS devices suitable for the area and also at the smaller scale, in order to achieve greenfield runoff rates. A method to create a series of maps using geographical information is shown, to indicate feasible locations for SuDS devices across the local government authority area. Applying the larger scale maps, a management train was designed for a smaller-scale regeneration site using MicroDrainage® software to control runoff at greenfield rates. The generated maps were constructed to provide initial guidance to local government on suitable SuDS at individual sites in a planning area. At all scales, the decision about which device to select was complex and influenced by a range of factors, with slightly different problems encountered. There was overall agreement between large and small scale models.

The production of reduced graphene oxide by a low-cost vacuum system for supercapacitors applications

International Nuclear Information System (INIS)

Cardoso, Q.A.; Sakata, S.K.; Faria, R.N.; Silva, F.M.; Vieira, L.S.; Casini, J.C.S.

2016-01-01

Graphene (G) has attracted great interest for its excellent electrical properties. However, the large-scale production of graphene is still currently under investigations. Graphene oxide (GO) can be partially reduced to graphene-like sheets by removing the oxygen-containing groups with the recovery of a conjugated structure. It can be produced using inexpensive graphite as raw material by cost-effective chemical methods. High vacuum and temperature (10 -7 mbar/1100 deg C) is well established as an effective route for reduced powder preparation on a laboratory scale. However, a high vacuum reduction system, which can be routinely operated at 10 -7 mbar, has a considerable capital, operational and maintenance cost to be used in a large scale. In the present work, a low-cost route aiming large scale reduction of graphene oxide has been investigated. A stainless steel vessel has been evacuated to backing-pump pressure (10 -2 mbar) to process graphene oxide at low and high temperatures. Attempts of reducing GO powder using low vacuum pressures have been carried out and investigated by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The experimental results of processing graphene oxide powder at various temperatures (200-1000°C) at relatively low pressures have been reported. The microstructures of the processed material have been investigated using scanning electron microscopy (SEM) and chemical microanalyses employing energy dispersive X-ray analysis (EDX). (author)

Multi-scale analysis of compressible fluctuations in the solar wind

Energy Technology Data Exchange (ETDEWEB)

Roberts, Owen W.; Escoubet, C. Philippe [ESA/ESTEC SCI-S, Noordwijk (Netherlands); Narita, Yasuhito [Austrian Academy of Sciences, Graz (Austria). Space Research Inst.

2018-04-01

Compressible plasma turbulence is investigated in the fast solar wind at proton kinetic scales by the combined use of electron density and magnetic field measurements. Both the scale-dependent cross-correlation (CC) and the reduced magnetic helicity (σ{sub m}) are used in tandem to determine the properties of the compressible fluctuations at proton kinetic scales. At inertial scales the turbulence is hypothesised to contain a mixture of Alfvenic and slow waves, characterised by weak magnetic helicity and anti-correlation between magnetic field strength B and electron density n{sub e}. At proton kinetic scales the observations suggest that the fluctuations have stronger positive magnetic helicities as well as strong anti-correlations within the frequency range studied. These results are interpreted as being characteristic of either counter-propagating kinetic Alfven wave packets or a mixture of anti-sunward kinetic Alfven waves along with a component of kinetic slow waves.

Design of a non-scaling FFAG accelerator for proton therapy

International Nuclear Information System (INIS)

Trbojevic, D.; Ruggiero, A.G.; Keil, E.; Neskovic, N.; Belgrade, Vinca; Sessler, A.

2005-01-01

In recent years there has been a revival of interest in Fixed Field Alternating Gradient (FFAG) accelerators. In Japan a number have been built, or are under construction. A new non-scaling approach to the FFAG reduces the required orbit offsets during acceleration and the size of the required aperture, while maintaining the advantage of the low cost magnets associated with fixed fields. An advantage of the non-scaling FFAG accelerator, with respect to synchrotrons, is the fixed field and hence the possibility of high current and high repetition rate for spot scanning. There are possible advantages of the nonscaling design with respect to fixed-field cyclotrons. The non-scaling FFAG allows strong focusing and hence smaller aperture requirements compared to scaling designs, thus leading to very low losses and better control over the beam. We present, here, a non-scaling FFAG designed to be used for proton therapy

Optimizing rice yields while minimizing yield-scaled global warming potential.

Science.gov (United States)

Pittelkow, Cameron M; Adviento-Borbe, Maria A; van Kessel, Chris; Hill, James E; Linquist, Bruce A

2014-05-01

To meet growing global food demand with limited land and reduced environmental impact, agricultural greenhouse gas (GHG) emissions are increasingly evaluated with respect to crop productivity, i.e., on a yield-scaled as opposed to area basis. Here, we compiled available field data on CH4 and N2 O emissions from rice production systems to test the hypothesis that in response to fertilizer nitrogen (N) addition, yield-scaled global warming potential (GWP) will be minimized at N rates that maximize yields. Within each study, yield N surplus was calculated to estimate deficit or excess N application rates with respect to the optimal N rate (defined as the N rate at which maximum yield was achieved). Relationships between yield N surplus and GHG emissions were assessed using linear and nonlinear mixed-effects models. Results indicate that yields increased in response to increasing N surplus when moving from deficit to optimal N rates. At N rates contributing to a yield N surplus, N2 O and yield-scaled N2 O emissions increased exponentially. In contrast, CH4 emissions were not impacted by N inputs. Accordingly, yield-scaled CH4 emissions decreased with N addition. Overall, yield-scaled GWP was minimized at optimal N rates, decreasing by 21% compared to treatments without N addition. These results are unique compared to aerobic cropping systems in which N2 O emissions are the primary contributor to GWP, meaning yield-scaled GWP may not necessarily decrease for aerobic crops when yields are optimized by N fertilizer addition. Balancing gains in agricultural productivity with climate change concerns, this work supports the concept that high rice yields can be achieved with minimal yield-scaled GWP through optimal N application rates. Moreover, additional improvements in N use efficiency may further reduce yield-scaled GWP, thereby strengthening the economic and environmental sustainability of rice systems. © 2013 John Wiley & Sons Ltd.

Emotional intelligence scale for medical students

Directory of Open Access Journals (Sweden)

Kalpana Srivastava

2011-01-01

Full Text Available Background: Emotional Intelligence has been associated with positive outcome process in varied professions. There is paucity of Indian literature on the subject; especially involving medical undergraduates; and presently there is no scale available to measure the same in the Indian scenario. Objective: To develop a scale to measure Emotional Intelligence among medical undergraduates. Materials and Methods: Four domains of Emotional intelligence were selected, viz. Self-Awareness, Self-Management, Social-Awareness & Social-Skills and these were included for the purpose of domains of the scale. On the basis of focused group discussions and in-depth deliberations with experts, undergraduate and postgraduate medical students a pool of 50 items was generated. The items were reduced to 27 based on expert consensus and on the basis of frequency of endorsement by expert reviews. It was followed by a pilot study of 50 undergraduates. This completed the preparation of the preliminary draft based on content analysis. The questionnaire was then administered in 480 students and the data was analyzed by appropriate statistical methods. For the purpose of concurrent validity, emotional intelligence scale developed by Dr. Ekta was used. Results: The Cronbach′s Alpha for Internal Consistency Reliability was 0.68. The EIS had a significant correlation with social awareness domain of Emotional Intelligence Test (EIT establishing Concurrent Validity. Conclusion: Emotional Intelligence Scale for medical undergraduates was constructed. Reliability and concurrent validity were also established for the same.

Dissimilatory nitrogen reduction in intertidal sediments of a temperate estuary: small scale heterogeneity and novel nitrate-to-ammonium reducers.

Directory of Open Access Journals (Sweden)

Helen eDecleyre

2015-10-01

Full Text Available The estuarine nitrogen cycle can be substantially altered due to anthropogenic activities resulting in increased amounts of inorganic nitrogen (mainly nitrate. In the past, denitrification was considered to be the main ecosystem process removing reactive nitrogen from the estuarine ecosystem. However, recent reports on the contribution of dissimilatory nitrate reduction to ammonium (DNRA to nitrogen removal in these systems indicated a similar or higher importance, although the ratio between both processes remains ambiguous. Compared to denitrification, DNRA has been underexplored for the last decades and the key organisms carrying out the process in marine environments are largely unknown. Hence, as a first step to better understand the interplay between denitrification, DNRA and reduction of nitrate to nitrite in estuarine sediments, nitrogen reduction potentials were determined in sediments of the Paulina polder mudflat (Westerschelde estuary. We observed high variability in dominant nitrogen removing processes over a short distance (1.6 m, with nitrous oxide, ammonium and nitrite production rates differing significantly between all sampling sites. Denitrification occurred at all sites, DNRA was either the dominant process (two out of five sites or absent, while nitrate reduction to nitrite was observed in most sites but never dominant. In addition, novel nitrate-to-ammonium reducers assigned to Thalassospira, Celeribacter and Halomonas, for which DNRA was thus far unreported, were isolated, with DNRA phenotype reconfirmed through nrfA gene amplification. This study demonstrates high small scale heterogeneity among dissimilatory nitrate reduction processes in estuarine sediments and provides novel marine DNRA organisms that represent valuable alternatives to the current model organisms.

Dissimilatory nitrogen reduction in intertidal sediments of a temperate estuary: small scale heterogeneity and novel nitrate-to-ammonium reducers.

Science.gov (United States)

Decleyre, Helen; Heylen, Kim; Van Colen, Carl; Willems, Anne

2015-01-01

The estuarine nitrogen cycle can be substantially altered due to anthropogenic activities resulting in increased amounts of inorganic nitrogen (mainly nitrate). In the past, denitrification was considered to be the main ecosystem process removing reactive nitrogen from the estuarine ecosystem. However, recent reports on the contribution of dissimilatory nitrate reduction to ammonium (DNRA) to nitrogen removal in these systems indicated a similar or higher importance, although the ratio between both processes remains ambiguous. Compared to denitrification, DNRA has been underexplored for the last decades and the key organisms carrying out the process in marine environments are largely unknown. Hence, as a first step to better understand the interplay between denitrification, DNRA and reduction of nitrate to nitrite in estuarine sediments, nitrogen reduction potentials were determined in sediments of the Paulina polder mudflat (Westerschelde estuary). We observed high variability in dominant nitrogen removing processes over a short distance (1.6 m), with nitrous oxide, ammonium and nitrite production rates differing significantly between all sampling sites. Denitrification occurred at all sites, DNRA was either the dominant process (two out of five sites) or absent, while nitrate reduction to nitrite was observed in most sites but never dominant. In addition, novel nitrate-to-ammonium reducers assigned to Thalassospira, Celeribacter, and Halomonas, for which DNRA was thus far unreported, were isolated, with DNRA phenotype reconfirmed through nrfA gene amplification. This study demonstrates high small scale heterogeneity among dissimilatory nitrate reduction processes in estuarine sediments and provides novel marine DNRA organisms that represent valuable alternatives to the current model organisms.

Effectiveness of methods for reducing acrylamide in bakery products.

Science.gov (United States)

Sadd, Peter A; Hamlet, Colin G; Liang, Li

2008-08-13

Pilot-scale bread, biscuit, and cracker doughs have been baked to assess how well recipe changes could reduce acrylamide in commercial bakery products. Removing ammonium-based raising agents was beneficial in biscuits. In doughs, long yeast fermentations were an effective way of reducing asparagine levels and hence acrylamide. At moderate fermentation times fructose levels increased, but the yeast later absorbed this, so the net effect on acrylamide was beneficial. Metal ions such as calcium reduced acrylamide when added as the carbonate or chloride. Hence, the fortification of flour with calcium carbonate, over and above its natural mineral content, has an additional benefit. However, some other possible methods of adding calcium to bakery doughs, for example, via the permitted preservative calcium propionate, were not beneficial. Amino acid addition to doughs gave modest reductions in acrylamide. Lowering the dough pH reduced acrylamide, but at the expense of higher levels of other process contaminants such as 3-monochloropropane-1,2-diol (3-MCPD).

Vegetated treatment area (VTAs) efficiencies for E. coli and nutrient removal on small-scale swine operations

OpenAIRE

R. Daren Harmel; Rehanon Pampell; Terry Gentry; Doug R. Smith; Chad Hajda; Kevin Wagner; Patti K. Smith; Rick L. Haney; Kori D. Higgs

2018-01-01

As small-scale animal feeding operations work to manage their byproducts and avoid regulation, they need practical, cost-effective methods to reduce environmental impact. One such option is using vegetative treatment areas (VTAs) with perennial grasses to treat runoff; however, research is limited on VTA effectiveness as a waste management alternative for smaller operations. This study evaluated the efficiencies of VTAs in reducing bacteria and nutrient runoff from small-scale swine operation...

Climate, duration, and N placement determine N2 O emissions in reduced tillage systems: a meta-analysis.

Science.gov (United States)

van Kessel, Chris; Venterea, Rodney; Six, Johan; Adviento-Borbe, Maria Arlene; Linquist, Bruce; van Groenigen, Kees Jan

2013-01-01

No-tillage and reduced tillage (NT/RT) management practices are being promoted in agroecosystems to reduce erosion, sequester additional soil C and reduce production costs. The impact of NT/RT on N2 O emissions, however, has been variable with both increases and decreases in emissions reported. Herein, we quantitatively synthesize studies on the short- and long-term impact of NT/RT on N2 O emissions in humid and dry climatic zones with emissions expressed on both an area- and crop yield-scaled basis. A meta-analysis was conducted on 239 direct comparisons between conventional tillage (CT) and NT/RT. In contrast to earlier studies, averaged across all comparisons, NT/RT did not alter N2 O emissions compared with CT. However, NT/RT significantly reduced N2 O emissions in experiments >10 years, especially in dry climates. No significant correlation was found between soil texture and the effect of NT/RT on N2 O emissions. When fertilizer-N was placed at ≥5 cm depth, NT/RT significantly reduced area-scaled N2 O emissions, in particular under humid climatic conditions. Compared to CT under dry climatic conditions, yield-scaled N2 O increased significantly (57%) when NT/RT was implemented <10 years, but decreased significantly (27%) after ≥10 years of NT/RT. There was a significant decrease in yield-scaled N2 O emissions in humid climates when fertilizer-N was placed at ≥5 cm depth. Therefore, in humid climates, deep placement of fertilizer-N is recommended when implementing NT/RT. In addition, NT/RT practices need to be sustained for a prolonged time, particularly in dry climates, to become an effective mitigation strategy for reducing N2 O emissions. © 2012 Blackwell Publishing Ltd.

Scaling of ion implanted Si:P single electron devices

International Nuclear Information System (INIS)

Escott, C C; Hudson, F E; Chan, V C; Petersson, K D; Clark, R G; Dzurak, A S

2007-01-01

We present a modelling study on the scaling prospects for phosphorus in silicon (Si:P) single electron devices using readily available commercial and free-to-use software. The devices comprise phosphorus ion implanted, metallically doped (n + ) dots (size range 50-500 nm) with source and drain reservoirs. Modelling results are compared to measurements on fabricated devices and discussed in the context of scaling down to few-electron structures. Given current fabrication constraints, we find that devices with 70-75 donors per dot should be realizable. We comment on methods for further reducing this number

Scaling of ion implanted Si:P single electron devices

Energy Technology Data Exchange (ETDEWEB)

Escott, C C [Centre for Quantum Computer Technology, School of Electrical Engineering and Telecommunications, UNSW, Sydney, NSW 2052 (Australia); Hudson, F E [Centre for Quantum Computer Technology, School of Electrical Engineering and Telecommunications, UNSW, Sydney, NSW 2052 (Australia); Chan, V C [Centre for Quantum Computer Technology, School of Electrical Engineering and Telecommunications, UNSW, Sydney, NSW 2052 (Australia); Petersson, K D [Centre for Quantum Computer Technology, School of Electrical Engineering and Telecommunications, UNSW, Sydney, NSW 2052 (Australia); Clark, R G [Centre for Quantum Computer Technology, School of Physics, UNSW, Sydney, 2052 (Australia); Dzurak, A S [Centre for Quantum Computer Technology, School of Electrical Engineering and Telecommunications, UNSW, Sydney, NSW 2052 (Australia)

2007-06-13

We present a modelling study on the scaling prospects for phosphorus in silicon (Si:P) single electron devices using readily available commercial and free-to-use software. The devices comprise phosphorus ion implanted, metallically doped (n{sup +}) dots (size range 50-500 nm) with source and drain reservoirs. Modelling results are compared to measurements on fabricated devices and discussed in the context of scaling down to few-electron structures. Given current fabrication constraints, we find that devices with 70-75 donors per dot should be realizable. We comment on methods for further reducing this number.

Small-scale production and utilization of wood fuels; Puupolttoaineen pientuotanto ja -kaeyttoe - katsaus tutkimus- projekteihin

Energy Technology Data Exchange (ETDEWEB)

Tuomi, S [Work Efficiency Inst., Rajamaeki (Finland)

1997-12-31

The objective of the research on small-scale production of wood fuels was to promote the forest owners` own utilization and procurement of firewood. The profitability of firewood was improved by developing new farm-tractor mountable equipment and methods for forest owners and small-entrepreneurs for harvesting of first-thinning wood and other small-dimeter wood. Totally new solution for machine felling of small trees and chopwood production were developed to serial production level. Recyclable processing and delivery units were developed for delivery of chopwood. A calculation model for analysing the costs of small-scale production of firewood became ready. A guide on the development of heating-entrepreneur activities, serving the entrepreneurs, was published. The objective of the firewood utilization research was to reduce the technical barriers of the utilization of firewood in small-house and real-estate scales. The main aim was to reduce the flue-gas emissions. The emissions of the fireplaces were reduced by developing the construction of fireplaces, catalytic combustion and heating methods. An automatic stoker-burner was developed for real-estate scale and a boiler series was designed for biofuels

Small-scale production and utilization of wood fuels; Puupolttoaineen pientuotanto ja -kaeyttoe - katsaus tutkimus- projekteihin

Energy Technology Data Exchange (ETDEWEB)

Tuomi, S. [Work Efficiency Inst., Rajamaeki (Finland)

1996-12-31

The objective of the research on small-scale production of wood fuels was to promote the forest owners` own utilization and procurement of firewood. The profitability of firewood was improved by developing new farm-tractor mountable equipment and methods for forest owners and small-entrepreneurs for harvesting of first-thinning wood and other small-dimeter wood. Totally new solution for machine felling of small trees and chopwood production were developed to serial production level. Recyclable processing and delivery units were developed for delivery of chopwood. A calculation model for analysing the costs of small-scale production of firewood became ready. A guide on the development of heating-entrepreneur activities, serving the entrepreneurs, was published. The objective of the firewood utilization research was to reduce the technical barriers of the utilization of firewood in small-house and real-estate scales. The main aim was to reduce the flue-gas emissions. The emissions of the fireplaces were reduced by developing the construction of fireplaces, catalytic combustion and heating methods. An automatic stoker-burner was developed for real-estate scale and a boiler series was designed for biofuels

Development and validation of the activity significance personal evaluation (ASPEn) scale.

Science.gov (United States)

Mallinson, Trudy; Schepens Niemiec, Stacey L; Carlson, Mike; Leland, Natalie; Vigen, Cheryl; Blanchard, Jeanine; Clark, Florence

2014-12-01

Engagement in desired occupations can promote health and wellbeing in older adults. Assessments of engagement often measure frequency, amount or importance of specific activities. This study aimed to develop a scale to measure older adults' evaluation of the extent to which their everyday activities are contributing to their health and wellness. Eighteen items, each scored with a seven-point rating scale, were initially developed by content experts, covering perceptions of how daily activities contribute to physical and mental health, as well as satisfaction and activity participation in the last six months. Rasch analysis methods were used to refine the scale using the pencil and paper responses of 460 community-living older adults. Initial Rasch analysis indicated three unlabelled rating scale categories were seldom used, reducing measurement precision. Five items were conceptually different by misfit statistics and principal component analysis. Subsequently, those items were removed and the number of rating scale steps reduced to 4. The remaining 13-item, 4-step scale, termed the Activity Significance Personal Evaluation (ASPEn), formed a unidimensional hierarchy with good fit statistics and targeting. Person separation reliability (2.7) and internal consistency (.91) indicated the tool is appropriate for individual person measurement. Relative validity indicated equivalence between Rasch measures and total raw scores. ASPEn is a brief, easily administered assessment of older adults' perception of the contribution of everyday activities to personal health and wellness. ASPEn may facilitate occupational therapy practice by enabling clinicians to assess change in meaning of an older adult's activity over time. © 2014 Occupational Therapy Australia.

Islam and Environmental Consciousness: A New Scale Development.

Science.gov (United States)

Emari, Hossein; Vazifehdoust, Hossein; Nikoomaram, Hashem

2017-04-01

This research proposed a new construct, Islamic environmental consciousness (IEC), and developed a measurement scale to support this construct. Churchill's (J Mark Res 16(1):64-73, 1979) paradigm, adapted by Negra and Mzoughi (Internet Res 22(4):426-442, 2012), was utilized. A total of 32 items were generated based on the verses of the Qur'an from nine interviews with teachers in an Islamic seminary. This set of items was reduced to 19 after dropping redundant or non-representative items. In a pilot study, factor analysis of the 19-item scale yielded a two-factor structure scale of seven items with a reliability ranging from 0.7 to 0.8. The Islamic environmental consciousness scale (IECS) was statistically confirmed and validated in a subsequent investigation. The proposed measurement scale warrants further exploratory study. Future research should assess the IECS's validity across different Muslim countries, locales, and various Islamic schools of thought and practice. IEC is proposed as a new construct that focuses primarily on the Qur'an and seeks to achieve acceptance by both Sunni and Shia denominations. In this study, both cognitive attitudes and behavioral aspects were considered in the design of the IECS.

Scaling Theory for Pulsed Jet Mixed Vessels, Sparging, and Cyclic Feed Transport Systems for Slurries

Energy Technology Data Exchange (ETDEWEB)

Kuhn, William L.; Rector, David R.; Rassat, Scot D.; Enderlin, Carl W.; Minette, Michael J.; Bamberger, Judith A.; Josephson, Gary B.; Wells, Beric E.; Berglin, Eric J.

2013-09-27

This document is a previously unpublished work based on a draft report prepared by Pacific Northwest National Laboratory (PNNL) for the Hanford Waste Treatment and Immobilization Plant (WTP) in 2012. Work on the report stopped when WTP’s approach to testing changed. PNNL is issuing a modified version of the document a year later to preserve and disseminate the valuable technical work that was completed. This document establishes technical bases for evaluating the mixing performance of Waste Treatment Plant (WTP) pretreatment process tanks based on data from less-than-full-scale testing, relative to specified mixing requirements. The technical bases include the fluid mechanics affecting mixing for specified vessel configurations, operating parameters, and simulant properties. They address scaling vessel physical performance, simulant physical performance, and “scaling down” the operating conditions at full scale to define test conditions at reduced scale and “scaling up” the test results at reduced scale to predict the performance at full scale. Essentially, this document addresses the following questions: • Why and how can the mixing behaviors in a smaller vessel represent those in a larger vessel? • What information is needed to address the first question? • How should the information be used to predict mixing performance in WTP? The design of Large Scale Integrated Testing (LSIT) is being addressed in other, complementary documents.

Seismic safety in conducting large-scale blasts

Science.gov (United States)

Mashukov, I. V.; Chaplygin, V. V.; Domanov, V. P.; Semin, A. A.; Klimkin, M. A.

2017-09-01

In mining enterprises to prepare hard rocks for excavation a drilling and blasting method is used. With the approach of mining operations to settlements the negative effect of large-scale blasts increases. To assess the level of seismic impact of large-scale blasts the scientific staff of Siberian State Industrial University carried out expertise for coal mines and iron ore enterprises. Determination of the magnitude of surface seismic vibrations caused by mass explosions was performed using seismic receivers, an analog-digital converter with recording on a laptop. The registration results of surface seismic vibrations during production of more than 280 large-scale blasts at 17 mining enterprises in 22 settlements are presented. The maximum velocity values of the Earth’s surface vibrations are determined. The safety evaluation of seismic effect was carried out according to the permissible value of vibration velocity. For cases with exceedance of permissible values recommendations were developed to reduce the level of seismic impact.

Potential for improved radiation thermometry measurement uncertainty through implementing a primary scale in an industrial laboratory

Science.gov (United States)

Willmott, Jon R.; Lowe, David; Broughton, Mick; White, Ben S.; Machin, Graham

2016-09-01

A primary temperature scale requires realising a unit in terms of its definition. For high temperature radiation thermometry in terms of the International Temperature Scale of 1990 this means extrapolating from the signal measured at the freezing temperature of gold, silver or copper using Planck’s radiation law. The difficulty in doing this means that primary scales above 1000 °C require specialist equipment and careful characterisation in order to achieve the extrapolation with sufficient accuracy. As such, maintenance of the scale at high temperatures is usually only practicable for National Metrology Institutes, and calibration laboratories have to rely on a scale calibrated against transfer standards. At lower temperatures it is practicable for an industrial calibration laboratory to have its own primary temperature scale, which reduces the number of steps between the primary scale and end user. Proposed changes to the SI that will introduce internationally accepted high temperature reference standards might make it practicable to have a primary high temperature scale in a calibration laboratory. In this study such a scale was established by calibrating radiation thermometers directly to high temperature reference standards. The possible reduction in uncertainty to an end user as a result of the reduced calibration chain was evaluated.

Reducing dysfunctional beliefs about sleep does not significantly improve insomnia in cognitive behavioral therapy.

Science.gov (United States)

Okajima, Isa; Nakajima, Shun; Ochi, Moeko; Inoue, Yuichi

2014-01-01

The present study examined to examine whether improvement of insomnia is mediated by a reduction in sleep-related dysfunctional beliefs through cognitive behavioral therapy for insomnia. In total, 64 patients with chronic insomnia received cognitive behavioral therapy for insomnia consisting of 6 biweekly individual treatment sessions of 50 minutes in length. Participants were asked to complete the Athens Insomnia Scale and the Dysfunctional Beliefs and Attitudes about Sleep scale both at the baseline and at the end of treatment. The results showed that although cognitive behavioral therapy for insomnia greatly reduced individuals' scores on both scales, the decrease in dysfunctional beliefs and attitudes about sleep with treatment did not seem to mediate improvement in insomnia. The findings suggest that sleep-related dysfunctional beliefs endorsed by patients with chronic insomnia may be attenuated by cognitive behavioral therapy for insomnia, but changes in such beliefs are not likely to play a crucial role in reducing the severity of insomnia.

Ramp injector scale effects on supersonic combustion

Science.gov (United States)

Trebs, Adam

The combustion field downstream of a 10 degree compression ramp injector has been studied experimentally using wall static pressure measurement, OH-PLIF, and 2 kHz intensified video filtered for OH emission at 320 nm. Nominal test section entrance conditions were Mach 2, 131 kPa static pressure, and 756K stagnation temperature. The experiment was equipped with a variable length inlet duct that facilitated varying the boundary layer development length while the injector shock structure in relation to the combustor geometry remained nearly fixed. As the boundary within an engine varies with flight condition and does not scale linearly with the physical scale of the engine, the boundary layer scale relative to mixing structures of the engine becomes relevant to the problem of engine scaling and general engine performance. By varying the boundary layer thickness from 40% of the ramp height to 150% of the ramp height, changes in the combustion flowfield downstream of the injector could be diagnosed. It was found that flame shape changed, the persistence of the vortex cores was reduced, and combustion efficiency rose as the incident boundary layer grew.

Aespoe Hard Rock Laboratory. Evaluation of scaling records for TASA access tunnel

International Nuclear Information System (INIS)

Ittner, Henrik

2009-01-01

that excavation damages primarily are located near the small face in the end of blasting rounds It may have been possible to reduce the frequency of blasting caused scaling by applying a higher quality class to the excavation works. Reducing the look-out angel and the limit for allowed overbreak may also reduce the frequency of scaled blocks caused by the end of a bottom charge simply because it would generate a more continues geometry

Aespoe Hard Rock Laboratory. Evaluation of scaling records for TASA access tunnel

Energy Technology Data Exchange (ETDEWEB)

Ittner, Henrik (Chalmers Univ. of Technology, Goeteborg (Sweden))

2009-07-01

that excavation damages primarily are located near the small face in the end of blasting rounds It may have been possible to reduce the frequency of blasting caused scaling by applying a higher quality class to the excavation works. Reducing the look-out angel and the limit for allowed overbreak may also reduce the frequency of scaled blocks caused by the end of a bottom charge simply because it would generate a more continues geometry

Relative scale and the strength and deformability of rock masses

Science.gov (United States)

Schultz, Richard A.

1996-09-01

The strength and deformation of rocks depend strongly on the degree of fracturing, which can be assessed in the field and related systematically to these properties. Appropriate Mohr envelopes obtained from the Rock Mass Rating (RMR) classification system and the Hoek-Brown criterion for outcrops and other large-scale exposures of fractured rocks show that rock-mass cohesive strength, tensile strength, and unconfined compressive strength can be reduced by as much as a factor often relative to values for the unfractured material. The rock-mass deformation modulus is also reduced relative to Young's modulus. A "cook-book" example illustrates the use of RMR in field applications. The smaller values of rock-mass strength and deformability imply that there is a particular scale of observation whose identification is critical to applying laboratory measurements and associated failure criteria to geologic structures.

Scale models: A proven cost-effective tool for outage planning

Energy Technology Data Exchange (ETDEWEB)

Lee, R. [Commonwealth Edison Co., Morris, IL (United States); Segroves, R. [Sargent & Lundy, Chicago, IL (United States)

1995-03-01

As generation costs for operating nuclear stations have risen, more nuclear utilities have initiated efforts to improve cost effectiveness. Nuclear plant owners are also being challenged with lower radiation exposure limits and new revised radiation protection related regulations (10 CFR 20), which places further stress on their budgets. As source term reduction activities continue to lower radiation fields, reducing the amount of time spent in radiation fields becomes one of the most cost-effective ways of reducing radiation exposure. An effective approach for minimizing time spent in radiation areas is to use a physical scale model for worker orientation planning and monitoring maintenance, modifications, and outage activities. To meet the challenge of continued reduction in the annual cumulative radiation exposures, new cost-effective tools are required. One field-tested and proven tool is the physical scale model.

Linear-scaling implementation of the direct random-phase approximation

International Nuclear Information System (INIS)

Kállay, Mihály

2015-01-01

We report the linear-scaling implementation of the direct random-phase approximation (dRPA) for closed-shell molecular systems. As a bonus, linear-scaling algorithms are also presented for the second-order screened exchange extension of dRPA as well as for the second-order Møller–Plesset (MP2) method and its spin-scaled variants. Our approach is based on an incremental scheme which is an extension of our previous local correlation method [Rolik et al., J. Chem. Phys. 139, 094105 (2013)]. The approach extensively uses local natural orbitals to reduce the size of the molecular orbital basis of local correlation domains. In addition, we also demonstrate that using natural auxiliary functions [M. Kállay, J. Chem. Phys. 141, 244113 (2014)], the size of the auxiliary basis of the domains and thus that of the three-center Coulomb integral lists can be reduced by an order of magnitude, which results in significant savings in computation time. The new approach is validated by extensive test calculations for energies and energy differences. Our benchmark calculations also demonstrate that the new method enables dRPA calculations for molecules with more than 1000 atoms and 10 000 basis functions on a single processor

SEWGS Technology is Now Ready for Scale-up

Energy Technology Data Exchange (ETDEWEB)

Jansen, D.; Van Selow, E.; Cobden, P. [Energy research Centre of the Netherlands ECN (Netherlands); Manzolini, G.; Macchi, E.; Gazzani, M. [Politecnico di Milano PTM, Dipartimento di Energia (Italy); Blom, R.; Henriksen, P.P. [SINTEF, Trondheim (Norway); Beavis, R. [BP Alternative Energy (United Kingdom); Wright, A. [Air products PLC (United Kingdom)

2013-07-01

In the FP7 project CAESAR, Air Products, BP, ECN, SINTEF and Politecnico di Milano worked together in the further development of the SEWGS process with the objective to reduce the energy penalty and the costs per ton of CO2 avoided to less than 25 euro through optimization of sorbent materials, reactor and process design and smart integration of the SEWGS unit in a combined cycle power plant. The most promising applications for the SEWGS technology are IGCC power plants and in combined cycles power plants fuelled with blast furnace top gas. Extensive sorbent development work resulted in a new sorbent called ALKASORB+ with a high capacity resulting in cost of CO2 avoided for the IGCC application of 23 euro. This is a reduction of almost 40% compared to the Selexol capture case. Since ALKASORB+ requires much less steam in the regeneration, the specific primary energy consumption is reduced to 44% below the specific energy consumption for the Selexol (2.08 versus 3.71 MJLHV/kgCO2). From a technical point of view SEWGS is ready to move to the next development level, which is a pilot plant installation with a capacity of 35 ton CO2 per day. This is over 500 times larger than the current ECN's multi column SEWGS installation, but still 50 times smaller than an envisaged commercial scale installation. The pilot plant will prove the technology under field conditions and at a sufficiently large scale to enable further up-scaling, delivering both the basic design and investment costs of a full scale SEWGS demonstration plant.

Prediction of scale potential in ethylene glycol containing solutions

Energy Technology Data Exchange (ETDEWEB)

Sandengen, Kristian; Oestvold, Terje

2006-03-15

This work presents a method for scale prediction in MEG (Mono Ethylene Glycol / 1,2-ethane-diol) containing solutions. It is based on an existing PVT scale model using a Pitzer ion interaction model for the aqueous phase. The model is well suited for scale prediction in saline solutions, where the PVT part is necessary for calculating CO{sub 2} phase equilibria being critical for carbonate scale. MEG influences the equilibria contained in the model, and its effect has been added empirically. Thus the accuracy of the model is limited by the amount of available experimental data. The model is applicable in the range 0-99wt% MEG and includes a wide variety of salts. In addition to the aspects of scale modelling in MEG+water solutions, this work presents new experimental data on CaSO4 solubility (0-95wt% MEG and 22-80 deg.C). CaSO4 solubility is greatly reduced by MEG to an extent that ''Salting-out'' is possible. (author) (tk)

Air pollution and economics: Alternate use of fuels in small scale industries

International Nuclear Information System (INIS)

Rao, B.P.S.; Pandit, V.I.

1999-01-01

In developing countries the problem of air pollution was recognized earlier, however, it has acquired a greater dimension due to the conventional use of low grade fuels like coal, baggase, rice husk, etc. having high sulphur and ash content. The industrial sources contribute about 30--40% of the total emissions. In India, the small scale industries (low investment group) contribute about 60--80% of the total industrial emissions. These industries are characterized with various environmental pollution problems due to cluster of small scale industries located in sensitive area; use of low grade fuel, primitive processing techniques without emission abatement facilities etc., thus leading to enormous pollution in an confined region. Acute need was felt to reduce the pollution problem associated with small scale industries by use of cleaner fuel so as to reduce the localized problem. The paper presents the emissions associated with use of coal/coke, natural gas, LPG, and propane along with the fuel cost for small scale industrial sector of Agra, Firozabad and Mathura region. The studies carried out would find applicability to meet the air pollution standards based on shift in fuel and associated cost

The Stop-Only-While-Shocking algorithm reduces hands-off time by 17% during cardiopulmonary resuscitation

DEFF Research Database (Denmark)

Hansen, Lars Koch; Mohammed, Anna; Pedersen, Magnus

2016-01-01

INTRODUCTION: Reducing hands-off time during cardiopulmonary resuscitation (CPR) is believed to increase survival after cardiac arrests because of the sustaining of organ perfusion. The aim of our study was to investigate whether charging the defibrillator before rhythm analyses and shock delivery...... significantly reduced hands-off time compared with the European Resuscitation Council (ERC) 2010 CPR guideline algorithm in full-scale cardiac arrest scenarios. METHODS: The study was designed as a full-scale cardiac arrest simulation study including administration of drugs. Participants were randomized...... compressions. RESULTS: Sample size was calculated with an α of 0.05 and 80% power showed that we should test four scenarios with each algorithm. Twenty-nine physicians participated in 11 scenarios. Hands-off time was significantly reduced 17% using the SOWS algorithm compared with ERC2010 [22.1% (SD 2.3) hands...

Mid-term and scaling effects of forest residue mulching on post-fire runoff and soil erosion.

Science.gov (United States)

Prats, Sergio Alegre; Wagenbrenner, Joseph W; Martins, Martinho António Santos; Malvar, Maruxa Cortizo; Keizer, Jan Jacob

2016-12-15

Mulching is an effective post-fire soil erosion mitigation treatment. Experiments with forest residue mulch have demonstrated that it increased ground cover to 70% and reduced runoff and soil loss at small spatial scales and for short post-fire periods. However, no studies have systematically assessed the joint effects of scale, time since burning, and mulching on runoff, soil loss, and organic matter loss. The objective of this study was to evaluate the effects of scale and forest residue mulch using 0.25m 2 micro-plots and 100m 2 slope-scale plots in a burnt eucalypt plantation in central Portugal. We assessed the underlying processes involved in the post-fire hydrologic and erosive responses, particularly the effects of soil moisture and soil water repellency. Runoff amount in the micro-plots was more than ten-fold the runoff in the larger slope-scale plots in the first year and decreased to eight-fold in the third post-fire year. Soil losses in the micro-plots were initially about twice the values in the slope-scale plots and this ratio increased over time. The mulch greatly reduced the cumulative soil loss measured in the untreated slope-scale plots (616gm -2 ) by 91% during the five post-fire years. The implications are that applying forest residue mulch immediately after a wildfire can reduce soil losses at spatial scales of interest to land managers throughout the expected post-fire window of disturbance, and that mulching resulted in a substantial relative gain in soil organic matter. Copyright © 2016 Elsevier B.V. All rights reserved.

Large-scale Manufacturing of Nanoparticulate-based Lubrication Additives for Improved Energy Efficiency and Reduced Emissions

Energy Technology Data Exchange (ETDEWEB)

Erdemir, Ali [Argonne National Laboratory

2013-09-26

This project was funded under the Department of Energy (DOE) Lab Call on Nanomanufacturing for Energy Efficiency and was directed toward the development of novel boron-based nanocolloidal lubrication additives for improving the friction and wear performance of machine components in a wide range of industrial and transportation applications. Argonne's research team concentrated on the scientific and technical aspects of the project, using a range of state-of-the art analytical and tribological test facilities. Argonne has extensive past experience and expertise in working with boron-based solid and liquid lubrication additives, and has intellectual property ownership of several. There were two industrial collaborators in this project: Ashland Oil (represented by its Valvoline subsidiary) and Primet Precision Materials, Inc. (a leading nanomaterials company). There was also a sub-contract with the University of Arkansas. The major objectives of the project were to develop novel boron-based nanocolloidal lubrication additives and to optimize and verify their performance under boundary-lubricated sliding conditions. The project also tackled problems related to colloidal dispersion, larger-scale manufacturing and blending of nano-additives with base carrier oils. Other important issues dealt with in the project were determination of the optimum size and concentration of the particles and compatibility with various base fluids and/or additives. Boron-based particulate additives considered in this project included boric acid (H{sub 3}BO{sub 3}), hexagonal boron nitride (h-BN), boron oxide, and borax. As part of this project, we also explored a hybrid MoS{sub 2} + boric acid formulation approach for more effective lubrication and reported the results. The major motivation behind this work was to reduce energy losses related to friction and wear in a wide spectrum of mechanical systems and thereby reduce our dependence on imported oil. Growing concern over greenhouse

Centrifugal contractors for laboratory-scale solvent extraction tests

International Nuclear Information System (INIS)

Leonard, R.A.; Chamberlain, D.B.; Conner, C.

1995-01-01

A 2-cm contactor (minicontactor) was developed and used at Argonne National Laboratory for laboratory-scale testing of solvent extraction flowsheets. This new contactor requires only 1 L of simulated waste feed, which is significantly less than the 10 L required for the 4-cm unit that had previously been used. In addition, the volume requirements for the other aqueous and organic feeds are reduced correspondingly. This paper (1) discusses the design of the minicontactor, (2) describes results from having applied the minicontactor to testing various solvent extraction flowsheets, and (3) compares the minicontactor with the 4-cm contactor as a device for testing solvent extraction flowsheets on a laboratory scale

Dimensionality of the hospital anxiety and depression scale (HADS) in cardiac patients

DEFF Research Database (Denmark)

Emons, Wilco H M; Sijtsma, Klaas; Pedersen, Susanne S.

2012-01-01

The hospital anxiety and depression scale (HADS) measures anxiety and depressive symptoms and is widely used in clinical and nonclinical populations. However, there is some debate about the number of dimensions represented by the HADS. In a sample of 534 Dutch cardiac patients, this study examined...... items each were found to be structurally sound and reliable. These scales covered the two key attributes of anxiety and (anhedonic) depression. The findings suggest that the HADS may be reduced to a 10-item questionnaire comprising two 5-item scales measuring anxiety and depressive symptoms....

Multi-scale analysis of compressible fluctuations in the solar wind

Science.gov (United States)

Roberts, Owen W.; Narita, Yasuhito; Escoubet, C.-Philippe

2018-01-01

Compressible plasma turbulence is investigated in the fast solar wind at proton kinetic scales by the combined use of electron density and magnetic field measurements. Both the scale-dependent cross-correlation (CC) and the reduced magnetic helicity (σm) are used in tandem to determine the properties of the compressible fluctuations at proton kinetic scales. At inertial scales the turbulence is hypothesised to contain a mixture of Alfvénic and slow waves, characterised by weak magnetic helicity and anti-correlation between magnetic field strength B and electron density ne. At proton kinetic scales the observations suggest that the fluctuations have stronger positive magnetic helicities as well as strong anti-correlations within the frequency range studied. These results are interpreted as being characteristic of either counter-propagating kinetic Alfvén wave packets or a mixture of anti-sunward kinetic Alfvén waves along with a component of kinetic slow waves.

Implementation of a solution Cloud Computing with MapReduce model

International Nuclear Information System (INIS)

Baya, Chalabi

2014-01-01

In recent years, large scale computer systems have emerged to meet the demands of high storage, supercomputing, and applications using very large data sets. The emergence of Cloud Computing offers the potentiel for analysis and processing of large data sets. Mapreduce is the most popular programming model which is used to support the development of such applications. It was initially designed by Google for building large datacenters on a large scale, to provide Web search services with rapid response and high availability. In this paper we will test the clustering algorithm K-means Clustering in a Cloud Computing. This algorithm is implemented on MapReduce. It has been chosen for its characteristics that are representative of many iterative data analysis algorithms. Then, we modify the framework CloudSim to simulate the MapReduce execution of K-means Clustering on different Cloud Computing, depending on their size and characteristics of target platforms. The experiment show that the implementation of K-means Clustering gives good results especially for large data set and the Cloud infrastructure has an influence on these results

The Design of a Fire Source in Scale-Model Experiments with Smoke Ventilation

DEFF Research Database (Denmark)

Nielsen, Peter Vilhelm; Brohus, Henrik; la Cour-Harbo, H.

2004-01-01

The paper describes the design of a fire and a smoke source for scale-model experiments with smoke ventilation. It is only possible to work with scale-model experiments where the Reynolds number is reduced compared to full scale, and it is demonstrated that special attention to the fire source...... (heat and smoke source) may improve the possibility of obtaining Reynolds number independent solutions with a fully developed flow. The paper shows scale-model experiments for the Ofenegg tunnel case. Design of a fire source for experiments with smoke ventilation in a large room and smoke movement...

Data-Intensive Text Processing with MapReduce

CERN Document Server

Lin, Jimmy

2010-01-01

Our world is being revolutionized by data-driven methods: access to large amounts of data has generated new insights and opened exciting new opportunities in commerce, science, and computing applications. Processing the enormous quantities of data necessary for these advances requires large clusters, making distributed computing paradigms more crucial than ever. MapReduce is a programming model for expressing distributed computations on massive datasets and an execution framework for large-scale data processing on clusters of commodity servers. The programming model provides an easy-to-underst

Final air test results for the 1/5-scale Mark I boiling water reactor pressure suppression experiment

International Nuclear Information System (INIS)

Collins, E.K.; Lai, W.

1977-01-01

A loss-of-coolant accident (LOCA) in a boiling-water reactor (BWR) power plant has never occurred. However, because this type of accident is particularly severe, it is used as a principal basis for design. During a hypothetical LOCA in a Mark I BWR, air followed by steam is injected from a drywell into a toroidal wetwell about half-filled with water. A series of consistent, versatile, and accurate air-water tests simulating LOCA conditions was completed in the Lawrence Livermore Laboratory 1/5-Scale Mark I BWR Pressure Suppression Experimental Facility. Results from this test series were used to quantify the vertical loading function and to study the associated fluid dynamic phenomena. Detailed histories of vertical loads on the wetwell are shown. In particular, variations of hydrodynamic-generated vertical loads with changes in drywell pressurization rate, downcomer submergence, and the vent-line loss coefficient are established. Initial drywell overpressure, which partially preclears the downcomers of water, substantially reduces the peak vertical loads. Scaling relationships, developed from dimensional analysis and verified by bench-top experiments, allow the 1/5-scale results to be applied to a full-scale BWR power plant. This analysis leads to dimensionless groupings which are invariant. These groupongs show that if water is used as the working fluid, the magnitude of the forces in a scaled facility is reduced by the cube of the scale factor; the time when these forces occur is reduced by the square root of the scale factor

Modeling industrial centrifugation of mammalian cell culture using a capillary based scale-down system.

Science.gov (United States)

Westoby, Matthew; Rogers, Jameson K; Haverstock, Ryan; Romero, Jonathan; Pieracci, John

2011-05-01

Continuous-flow centrifugation is widely utilized as the primary clarification step in the recovery of biopharmaceuticals from cell culture. However, it is a challenging operation to develop and characterize due to the lack of easy to use, small-scale, systems that can be used to model industrial processes. As a result, pilot-scale continuous centrifugation is typically employed to model large-scale systems requiring a significant amount of resources. In an effort to reduce resource requirements and create a system which is easy to construct and utilize, a capillary shear device, capable of producing energy dissipation rates equivalent to those present in the feed zones of industrial disk stack centrifuges, was developed and evaluated. When coupled to a bench-top, batch centrifuge, the capillary device reduced centrate turbidity prediction error from 37% to 4% compared to using a bench-top centrifuge alone. Laboratory-scale parameters that are analogous to those routinely varied during industrial-scale continuous centrifugation were identified and evaluated for their utility in emulating disk stack centrifuge performance. The resulting relationships enable bench-scale process modeling of continuous disk stack centrifuges using an easily constructed, scalable, capillary shear device coupled to a typical bench-top centrifuge. Copyright © 2010 Wiley Periodicals, Inc.

INDIVIDUALIZED YOGA FOR REDUCING DEPRESSION AND ANXIETY, AND IMPROVING WELL-BEING: A RANDOMIZED CONTROLLED TRIAL.

Science.gov (United States)

de Manincor, Michael; Bensoussan, Alan; Smith, Caroline A; Barr, Kylie; Schweickle, Monica; Donoghoe, Lee-Lee; Bourchier, Suzannah; Fahey, Paul

2016-09-01

Depression and anxiety are leading causes of disability worldwide. Current treatments are primarily pharmaceutical and psychological. Questions remain about effectiveness and suitability for different people. Previous research suggests potential benefits of yoga for reducing depression and anxiety. The aim of this study is to investigate the effects of an individualized yoga intervention. A sample of 101 people with symptoms of depression and/or anxiety participated in a randomized controlled trial comparing a 6-week yoga intervention with waitlist control. Yoga was additional to usual treatment. The control group was offered the yoga following the waitlist period. Measures included Depression Anxiety Stress Scale (DASS-21), Kessler Psychological Distress Scale (K10), Short-Form Health Survey (SF12), Scale of Positive and Negative Experience (SPANE), Flourishing Scale (FS), and Connor-Davidson Resilience Scale (CD-RISC2). There were statistically significant differences between yoga and control groups on reduction of depression scores (-4.30; 95% CI: -7.70, -0.01; P = .01; ES -.44). Differences in reduced anxiety scores were not statistically significant (-1.91; 95% CI: -4.58, 0.76; P = .16). Statistically significant differences in favor of yoga were also found on total DASS (P = .03), K10, SF12 mental health, SPANE, FS, and resilience scores (P stress and SF12 physical health scores were not statistically significant. Benefits were maintained at 6-week follow-up. Yoga plus regular care was effective in reducing symptoms of depression compared with regular care alone. Further investigation is warranted regarding potential benefits in anxiety. Individualized yoga may be particularly beneficial in mental health care in the broader community. © 2016 Wiley Periodicals, Inc.

From micro-scale 3D simulations to macro-scale model of periodic porous media

Science.gov (United States)

Crevacore, Eleonora; Tosco, Tiziana; Marchisio, Daniele; Sethi, Rajandrea; Messina, Francesca

2015-04-01

In environmental engineering, the transport of colloidal suspensions in porous media is studied to understand the fate of potentially harmful nano-particles and to design new remediation technologies. In this perspective, averaging techniques applied to micro-scale numerical simulations are a powerful tool to extrapolate accurate macro-scale models. Choosing two simplified packing configurations of soil grains and starting from a single elementary cell (module), it is possible to take advantage of the periodicity of the structures to reduce the computation costs of full 3D simulations. Steady-state flow simulations for incompressible fluid in laminar regime are implemented. Transport simulations are based on the pore-scale advection-diffusion equation, that can be enriched introducing also the Stokes velocity (to consider the gravity effect) and the interception mechanism. Simulations are carried on a domain composed of several elementary modules, that serve as control volumes in a finite volume method for the macro-scale method. The periodicity of the medium involves the periodicity of the flow field and this will be of great importance during the up-scaling procedure, allowing relevant simplifications. Micro-scale numerical data are treated in order to compute the mean concentration (volume and area averages) and fluxes on each module. The simulation results are used to compare the micro-scale averaged equation to the integral form of the macroscopic one, making a distinction between those terms that could be computed exactly and those for which a closure in needed. Of particular interest it is the investigation of the origin of macro-scale terms such as the dispersion and tortuosity, trying to describe them with micro-scale known quantities. Traditionally, to study the colloidal transport many simplifications are introduced, such those concerning ultra-simplified geometry that usually account for a single collector. Gradual removal of such hypothesis leads to a

SCALE-6 Sensitivity/Uncertainty Methods and Covariance Data

International Nuclear Information System (INIS)

Williams, Mark L.; Rearden, Bradley T.

2008-01-01

Computational methods and data used for sensitivity and uncertainty analysis within the SCALE nuclear analysis code system are presented. The methodology used to calculate sensitivity coefficients and similarity coefficients and to perform nuclear data adjustment is discussed. A description is provided of the SCALE-6 covariance library based on ENDF/B-VII and other nuclear data evaluations, supplemented by 'low-fidelity' approximate covariances. SCALE (Standardized Computer Analyses for Licensing Evaluation) is a modular code system developed by Oak Ridge National Laboratory (ORNL) to perform calculations for criticality safety, reactor physics, and radiation shielding applications. SCALE calculations typically use sequences that execute a predefined series of executable modules to compute particle fluxes and responses like the critical multiplication factor. SCALE also includes modules for sensitivity and uncertainty (S/U) analysis of calculated responses. The S/U codes in SCALE are collectively referred to as TSUNAMI (Tools for Sensitivity and UNcertainty Analysis Methodology Implementation). SCALE-6-scheduled for release in 2008-contains significant new capabilities, including important enhancements in S/U methods and data. The main functions of TSUNAMI are to (a) compute nuclear data sensitivity coefficients and response uncertainties, (b) establish similarity between benchmark experiments and design applications, and (c) reduce uncertainty in calculated responses by consolidating integral benchmark experiments. TSUNAMI includes easy-to-use graphical user interfaces for defining problem input and viewing three-dimensional (3D) geometries, as well as an integrated plotting package.

Una Hakika: Scaling Digital Solutions for Conflict Management in ...

International Development Research Centre (IDRC) Digital Library (Canada)

Una Hakika: Scaling Digital Solutions for Conflict Management in Kenya and Burma ... local government officials, and funders involved in peacebuilding, security, and ... its 2017 call for proposals to establish Cyber Policy Centres in the Global South. ... partnering on a new initiative, aimed at reducing the emerging risk that.

Tsallis Entropy and the Transition to Scaling in Fragmentation

Science.gov (United States)

Sotolongo-Costa, Oscar; Rodriguez, Arezky H.; Rodgers, G. J.

2000-12-01

By using the maximum entropy principle with Tsallis entropy we obtain a fragment size distribution function which undergoes a transition to scaling. This distribution function reduces to those obtained by other authors using Shannon entropy. The treatment is easily generalisable to any process of fractioning with suitable constraints.

Development of a foot impact scale for rheumatoid arthritis.

Science.gov (United States)

Helliwell, Philip; Reay, Naomi; Gilworth, Gill; Redmond, Anthony; Slade, Anita; Tennant, Alan; Woodburn, James

2005-06-15

To develop a new foot impact scale to assess foot status in rheumatoid arthritis (RA) using established qualitative methodology and the latest item response techniques (Rasch analysis). Foot problems in RA were explored by conducting qualitative interviews that were then used to generate items for a new foot impact scale. Further validation was undertaken following postal surveys and Rasch analysis. Analysis of the first postal survey (n = 192 responses) produced a 63-item binary response, 4-subscale instrument. The 4 subscales covered the domains impairment, activities, participation, and footwear. Following test-retest postal surveys and additional analysis, the instrument was reduced to a 2 subscale, 51-item questionnaire covering the domains of impairments/shoes and activities/participation. Initial results of these subscales indicate good psychometric properties, external validity, and test-retest reliability. A foot impact scale to assess the impact of RA and to measure the effect of interventions has been developed. The 2 scales comprising the instrument demonstrate good psychometric properties.

Large-scale testing of women in Copenhagen has not reduced the prevalence of Chlamydia trachomatis infections

DEFF Research Database (Denmark)

Westh, Henrik Torkil; Kolmos, H J

2003-01-01

OBJECTIVE: To examine the impact of a stable, large-scale enzyme immunoassay (EIA) Chlamydia trachomatis testing situation in Copenhagen, and to estimate the impact of introducing a genomic-based assay with higher sensitivity and specificity. METHODS: Over a five-year study period, 25 305-28 505...... and negative predictive values of the Chlamydia test result, new screening strategies for both men and women in younger age groups will be necessary if chlamydial infections are to be curtailed....

Decision aid on breast cancer screening reduces attendance rate: results of a large-scale, randomized, controlled study by the DECIDEO group

Science.gov (United States)

Bourmaud, Aurelie; Soler-Michel, Patricia; Oriol, Mathieu; Regnier, Véronique; Tinquaut, Fabien; Nourissat, Alice; Bremond, Alain; Moumjid, Nora; Chauvin, Franck

2016-01-01

Controversies regarding the benefits of breast cancer screening programs have led to the promotion of new strategies taking into account individual preferences, such as decision aid. The aim of this study was to assess the impact of a decision aid leaflet on the participation of women invited to participate in a national breast cancer screening program. This Randomized, multicentre, controlled trial. Women aged 50 to 74 years, were randomly assigned to receive either a decision aid or the usual invitation letter. Primary outcome was the participation rate 12 months after the invitation. 16 000 women were randomized and 15 844 included in the modified intention-to-treat analysis. The participation rate in the intervention group was 40.25% (3174/7885 women) compared with 42.13% (3353/7959) in the control group (p = 0.02). Previous attendance for screening (RR = 6.24; [95%IC: 5.75-6.77]; p < 0.0001) and medium household income (RR = 1.05; [95%IC: 1.01-1.09]; p = 0.0074) were independently associated with attendance for screening. This large-scale study demonstrates that the decision aid reduced the participation rate. The decision aid activate the decision making process of women toward non-attendance to screening. These results show the importance of promoting informed patient choices, especially when those choices cannot be anticipated. PMID:26883201

Reducing, Maintaining, or Escalating Uncertainty? The Development and Validation of Four Uncertainty Preference Scales Related to Cancer Information Seeking and Avoidance.

Science.gov (United States)

Carcioppolo, Nick; Yang, Fan; Yang, Qinghua

2016-09-01

Uncertainty is a central characteristic of many aspects of cancer prevention, screening, diagnosis, and treatment. Brashers's (2001) uncertainty management theory details the multifaceted nature of uncertainty and describes situations in which uncertainty can both positively and negatively affect health outcomes. The current study extends theory on uncertainty management by developing four scale measures of uncertainty preferences in the context of cancer. Two national surveys were conducted to validate the scales and assess convergent and concurrent validity. Results support the factor structure of each measure and provide general support across multiple validity assessments. These scales can advance research on uncertainty and cancer communication by providing researchers with measures that address multiple aspects of uncertainty management.

The production of reduced graphene oxide by a low-cost vacuum system for supercapacitors applications

Energy Technology Data Exchange (ETDEWEB)

Cardoso, Q.A.; Sakata, S.K.; Faria, R.N. [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil); Silva, F.M.; Vieira, L.S.; Casini, J.C.S., E-mail: julio.casini@ifro.edu.br [Instituto Federal de Ciencia e Tecnologia de Rondonia (IFRO), RO (Brazil)

2016-07-01

Graphene (G) has attracted great interest for its excellent electrical properties. However, the large-scale production of graphene is still currently under investigations. Graphene oxide (GO) can be partially reduced to graphene-like sheets by removing the oxygen-containing groups with the recovery of a conjugated structure. It can be produced using inexpensive graphite as raw material by cost-effective chemical methods. High vacuum and temperature (10{sup -7}mbar/1100 deg C) is well established as an effective route for reduced powder preparation on a laboratory scale. However, a high vacuum reduction system, which can be routinely operated at 10{sup -7} mbar, has a considerable capital, operational and maintenance cost to be used in a large scale. In the present work, a low-cost route aiming large scale reduction of graphene oxide has been investigated. A stainless steel vessel has been evacuated to backing-pump pressure (10{sup -2} mbar) to process graphene oxide at low and high temperatures. Attempts of reducing GO powder using low vacuum pressures have been carried out and investigated by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The experimental results of processing graphene oxide powder at various temperatures (200-1000°C) at relatively low pressures have been reported. The microstructures of the processed material have been investigated using scanning electron microscopy (SEM) and chemical microanalyses employing energy dispersive X-ray analysis (EDX). (author)

Scale dependence of deuteron electrodisintegration

Science.gov (United States)

More, S. N.; Bogner, S. K.; Furnstahl, R. J.

2017-11-01

Background: Isolating nuclear structure properties from knock-out reactions in a process-independent manner requires a controlled factorization, which is always to some degree scale and scheme dependent. Understanding this dependence is important for robust extractions from experiment, to correctly use the structure information in other processes, and to understand the impact of approximations for both. Purpose: We seek insight into scale dependence by exploring a model calculation of deuteron electrodisintegration, which provides a simple and clean theoretical laboratory. Methods: By considering various kinematic regions of the longitudinal structure function, we can examine how the components—the initial deuteron wave function, the current operator, and the final-state interactions (FSIs)—combine at different scales. We use the similarity renormalization group to evolve each component. Results: When evolved to different resolutions, the ingredients are all modified, but how they combine depends strongly on the kinematic region. In some regions, for example, the FSIs are largely unaffected by evolution, while elsewhere FSIs are greatly reduced. For certain kinematics, the impulse approximation at a high renormalization group resolution gives an intuitive picture in terms of a one-body current breaking up a short-range correlated neutron-proton pair, although FSIs distort this simple picture. With evolution to low resolution, however, the cross section is unchanged but a very different and arguably simpler intuitive picture emerges, with the evolved current efficiently represented at low momentum through derivative expansions or low-rank singular value decompositions. Conclusions: The underlying physics of deuteron electrodisintegration is scale dependent and not just kinematics dependent. As a result, intuition about physics such as the role of short-range correlations or D -state mixing in particular kinematic regimes can be strongly scale dependent

Investigating the dependence of SCM simulated precipitation and clouds on the spatial scale of large-scale forcing at SGP

Science.gov (United States)

Tang, Shuaiqi; Zhang, Minghua; Xie, Shaocheng

2017-08-01

Large-scale forcing data, such as vertical velocity and advective tendencies, are required to drive single-column models (SCMs), cloud-resolving models, and large-eddy simulations. Previous studies suggest that some errors of these model simulations could be attributed to the lack of spatial variability in the specified domain-mean large-scale forcing. This study investigates the spatial variability of the forcing and explores its impact on SCM simulated precipitation and clouds. A gridded large-scale forcing data during the March 2000 Cloud Intensive Operational Period at the Atmospheric Radiation Measurement program's Southern Great Plains site is used for analysis and to drive the single-column version of the Community Atmospheric Model Version 5 (SCAM5). When the gridded forcing data show large spatial variability, such as during a frontal passage, SCAM5 with the domain-mean forcing is not able to capture the convective systems that are partly located in the domain or that only occupy part of the domain. This problem has been largely reduced by using the gridded forcing data, which allows running SCAM5 in each subcolumn and then averaging the results within the domain. This is because the subcolumns have a better chance to capture the timing of the frontal propagation and the small-scale systems. Other potential uses of the gridded forcing data, such as understanding and testing scale-aware parameterizations, are also discussed.

Thinking, Fast and Slow? Some Field Experiments to Reduce Crime and Dropout in Chicago*

OpenAIRE

Heller, Sara B.; Shah, Anuj K.; Guryan, Jonathan; Ludwig, Jens; Mullainathan, Sendhil; Pollack, Harold A.

2016-01-01

Abstract We present the results of three large-scale randomized controlled trials (RCTs) carried out in Chicago, testing interventions to reduce crime and dropout by changing the decision making of economically disadvantaged youth. We study a program called Becoming a Man (BAM), developed by the nonprofit Youth Guidance, in two RCTs implemented in 2009–2010 and 2013–2015. In the two studies participation in the program reduced total arrests during the intervention period by 28–35%, reduced vi...

Lattice Boltzmann flow simulations with applications of reduced order modeling techniques

KAUST Repository

Brown, Donald

2014-01-01

With the recent interest in shale gas, an understanding of the flow mechanisms at the pore scale and beyond is necessary, which has attracted a lot of interest from both industry and academia. One of the suggested algorithms to help understand flow in such reservoirs is the Lattice Boltzmann Method (LBM). The primary advantage of LBM is its ability to approximate complicated geometries with simple algorithmic modificatoins. In this work, we use LBM to simulate the flow in a porous medium. More specifically, we use LBM to simulate a Brinkman type flow. The Brinkman law allows us to integrate fast free-flow and slow-flow porous regions. However, due to the many scales involved and complex heterogeneities of the rock microstructure, the simulation times can be long, even with the speed advantage of using an explicit time stepping method. The problem is two-fold, the computational grid must be able to resolve all scales and the calculation requires a steady state solution implying a large number of timesteps. To help reduce the computational complexity and total simulation times, we use model reduction techniques to reduce the dimension of the system. In this approach, we are able to describe the dynamics of the flow by using a lower dimensional subspace. In this work, we utilize the Proper Orthogonal Decomposition (POD) technique, to compute the dominant modes of the flow and project the solution onto them (a lower dimensional subspace) to arrive at an approximation of the full system at a lowered computational cost. We present a few proof-of-concept examples of the flow field and the corresponding reduced model flow field.

Scaling of Metabolic Scaling within Physical Limits

Directory of Open Access Journals (Sweden)

Douglas S. Glazier

2014-10-01

Full Text Available Both the slope and elevation of scaling relationships between log metabolic rate and log body size vary taxonomically and in relation to physiological or developmental state, ecological lifestyle and environmental conditions. Here I discuss how the recently proposed metabolic-level boundaries hypothesis (MLBH provides a useful conceptual framework for explaining and predicting much, but not all of this variation. This hypothesis is based on three major assumptions: (1 various processes related to body volume and surface area exert state-dependent effects on the scaling slope for metabolic rate in relation to body mass; (2 the elevation and slope of metabolic scaling relationships are linked; and (3 both intrinsic (anatomical, biochemical and physiological and extrinsic (ecological factors can affect metabolic scaling. According to the MLBH, the diversity of metabolic scaling relationships occurs within physical boundary limits related to body volume and surface area. Within these limits, specific metabolic scaling slopes can be predicted from the metabolic level (or scaling elevation of a species or group of species. In essence, metabolic scaling itself scales with metabolic level, which is in turn contingent on various intrinsic and extrinsic conditions operating in physiological or evolutionary time. The MLBH represents a “meta-mechanism” or collection of multiple, specific mechanisms that have contingent, state-dependent effects. As such, the MLBH is Darwinian in approach (the theory of natural selection is also meta-mechanistic, in contrast to currently influential metabolic scaling theory that is Newtonian in approach (i.e., based on unitary deterministic laws. Furthermore, the MLBH can be viewed as part of a more general theory that includes other mechanisms that may also affect metabolic scaling.

Comparison of the Fullerton Advanced Balance Scale, Mini-BESTest, and Berg Balance Scale to Predict Falls in Parkinson Disease.

Science.gov (United States)

Schlenstedt, Christian; Brombacher, Stephanie; Hartwigsen, Gesa; Weisser, Burkhard; Möller, Bettina; Deuschl, Günther

2016-04-01

The correct identification of patients with Parkinson disease (PD) at risk for falling is important to initiate appropriate treatment early. This study compared the Fullerton Advanced Balance (FAB) scale with the Mini-Balance Evaluation Systems Test (Mini-BESTest) and Berg Balance Scale (BBS) to identify individuals with PD at risk for falls and to analyze which of the items of the scales best predict future falls. This was a prospective study to assess predictive criterion-related validity. The study was conducted at a university hospital in an urban community. Eighty-five patients with idiopathic PD (Hoehn and Yahr stages: 1-4) participated in the study. Measures were number of falls (assessed prospectively over 6 months), FAB scale, Mini-BESTest, BBS, and Unified Parkinson's Disease Rating Scale. The FAB scale, Mini-BESTest, and BBS showed similar accuracy to predict future falls, with values for area under the curve (AUC) of the receiver operating characteristic (ROC) curve of 0.68, 0.65, and 0.69, respectively. A model combining the items "tandem stance," "rise to toes," "one-leg stance," "compensatory stepping backward," "turning," and "placing alternate foot on stool" had an AUC of 0.84 of the ROC curve. There was a dropout rate of 19/85 participants. The FAB scale, Mini-BESTest, and BBS provide moderate capacity to predict "fallers" (people with one or more falls) from "nonfallers." Only some items of the 3 scales contribute to the detection of future falls. Clinicians should particularly focus on the item "tandem stance" along with the items "one-leg stance," "rise to toes," "compensatory stepping backward," "turning 360°," and "placing foot on stool" when analyzing postural control deficits related to fall risk. Future research should analyze whether balance training including the aforementioned items is effective in reducing fall risk. © 2016 American Physical Therapy Association.

Manufacturing test of large scale hollow capsule and long length cladding in the large scale oxide dispersion strengthened (ODS) martensitic steel

International Nuclear Information System (INIS)

Narita, Takeshi; Ukai, Shigeharu; Kaito, Takeji; Ohtsuka, Satoshi; Fujiwara, Masayuki

2004-04-01

Mass production capability of oxide dispersion strengthened (ODS) martensitic steel cladding (9Cr) has being evaluated in the Phase II of the Feasibility Studies on Commercialized Fast Reactor Cycle System. The cost for manufacturing mother tube (raw materials powder production, mechanical alloying (MA) by ball mill, canning, hot extrusion, and machining) is a dominant factor in the total cost for manufacturing ODS ferritic steel cladding. In this study, the large-sale 9Cr-ODS martensitic steel mother tube which is made with a large-scale hollow capsule, and long length claddings were manufactured, and the applicability of these processes was evaluated. Following results were obtained in this study. (1) Manufacturing the large scale mother tube in the dimension of 32 mm OD, 21 mm ID, and 2 m length has been successfully carried out using large scale hollow capsule. This mother tube has a high degree of accuracy in size. (2) The chemical composition and the micro structure of the manufactured mother tube are similar to the existing mother tube manufactured by a small scale can. And the remarkable difference between the bottom and top sides in the manufactured mother tube has not been observed. (3) The long length cladding has been successfully manufactured from the large scale mother tube which was made using a large scale hollow capsule. (4) For reducing the manufacturing cost of the ODS steel claddings, manufacturing process of the mother tubes using a large scale hollow capsules is promising. (author)

Research on performance evaluation and anti-scaling mechanism of green scale inhibitors by static and dynamic methods

International Nuclear Information System (INIS)

Liu, D.

2011-01-01

Increasing environmental concerns and discharge limitations have imposed additional challenges in treating process waters. Thus, the concept of 'Green Chemistry' was proposed and green scale inhibitors became a focus of water treatment technology. Finding some economical and environmentally friendly inhibitors is one of the major research focuses nowadays. In this dissertation, the inhibition performance of different phosphonates as CaCO 3 scale inhibitors in simulated cooling water was evaluated. Homo-, co-, and ter-polymers were also investigated for their performance as Ca-phosphonate inhibitors. Addition of polymers as inhibitors with phosphonates could reduce Ca-phosphonate precipitation and enhance the inhibition efficiency for CaCO 3 scale. The synergistic effect of poly-aspartic acid (PASP) and Poly-epoxy-succinic acid (PESA) on inhibition of scaling has been studied using both static and dynamic methods. Results showed that the anti-scaling performance of PASP combined with PESA was superior to that of PASP or PESA alone for CaCO 3 , CaSO 4 and BaSO 4 scale. The influence of dosage, temperature and Ca 2+ concentration was also investigated in simulated cooling water circuit. Moreover, SEM analysis demonstrated the modification of crystalline morphology in the presence of PASP and PESA. In this work, we also investigated the respective inhibition effectiveness of copper and zinc ions for scaling in drinking water by the method of Rapid Controlled Precipitation (RCP). The results indicated that the zinc ion and copper ion were high efficient inhibitors of low concentration, and the analysis of SEM and IR showed that copper and zinc ions could affect the calcium carbonate germination and change the crystal morphology. Moreover, the influence of temperature and dissolved CO 2 on the scaling potential of a mineral water (Salvetat) in the presence of copper and zinc ions was studied by laboratory experiments. An ideal scale inhibitor should be a solid form

The prospects of transition metal dichalcogenides for ultimately scaled CMOS

Science.gov (United States)

Thiele, S.; Kinberger, W.; Granzner, R.; Fiori, G.; Schwierz, F.

2018-05-01

MOSFET gate length scaling has been a main source of progress in digital electronics for decades. Today, researchers still spend considerable efforts on reducing the gate length and on developing ultimately scaled MOSFETs, thereby exploring both new device architectures and alternative channel materials beyond Silicon such as two-dimensional TMDs (transition metal dichalcogenide). On the other hand, the envisaged scaling scenario for the next 15 years has undergone a significant change recently. While the 2013 ITRS edition required a continuation of aggressive gate length scaling for at least another 15 years, the 2015 edition of the ITRS suggests a deceleration and eventually a levelling off of gate length scaling and puts more emphasis on alternative options such as pitch scaling to keep Moore's Law alive. In the present paper, future CMOS scaling is discussed in the light of emerging two-dimensional MOSFET channel, in particular two-dimensional TMDs. To this end, the scaling scenarios of the 2013 and 2015 ITRS editions are considered and the scaling potential of TMD MOSFETs is investigated by means of quantum-mechanical device simulations. It is shown that for ultimately scaled MOSFETs as required in the 2013 ITRS, the heavy carrier effective masses of the Mo- and W-based TMDs are beneficial for the suppression of direct source-drain tunneling, while to meet the significantly relaxed scaling targets of the 2016 ITRS heavy-effective-mass channels are not needed.

Pattern recognition invariant under changes of scale and orientation

Science.gov (United States)

Arsenault, Henri H.; Parent, Sebastien; Moisan, Sylvain

1997-08-01

We have used a modified method proposed by neiberg and Casasent to successfully classify five kinds of military vehicles. The method uses a wedge filter to achieve scale invariance, and lines in a multi-dimensional feature space correspond to each target with out-of-plane orientations over 360 degrees around a vertical axis. The images were not binarized, but were filtered in a preprocessing step to reduce aliasing. The feature vectors were normalized and orthogonalized by means of a neural network. Out-of-plane rotations of 360 degrees and scale changes of a factor of four were considered. Error-free classification was achieved.

To reduce the global burden of human schistosomiasis, use ‘old fashioned’ snail control

Science.gov (United States)

Sokolow, Susanne H.; Wood, Chelsea L.; Jones, Isabel J.; Lafferty, Kevin D.; Kuris, Armand; Hsieh, Michael H.; De Leo, Giulio A.

2018-01-01

Control strategies to reduce human schistosomiasis have evolved from ‘snail picking’ campaigns, a century ago, to modern wide-scale human treatment campaigns, or preventive chemotherapy. Unfortunately, despite the rise in preventive chemotherapy campaigns, just as many people suffer from schistosomiasis today as they did 50 years ago. Snail control can complement preventive chemotherapy by reducing the risk of transmission from snails to humans. Here, we present ideas for modernizing and scaling up snail control, including spatiotemporal targeting, environmental diagnostics, better molluscicides, new technologies (e.g., gene drive), and ‘outside the box’ strategies such as natural enemies, traps, and repellants. We conclude that, to achieve the World Health Assembly’s stated goal to eliminate schistosomiasis, it is time to give snail control another look.

Radiation dose in hysterosalpingography: modern 100mm fluorography vs. full-scale radiography

International Nuclear Information System (INIS)

Seppaenen, S.; Lehtinen, E.; Holli, H.

1978-01-01

Radiation doses of modern 100 mm fluorography and full-scale radiography were compared experimentally and applied to hysterosalpingography. It was determined that 100 mm fluorography reduced the doses by 28 to 29 percent per exposure and 37 to 47 percent per examination compared with full-scale radiography performed with fast tungstate screens in identical conditions (70 to 80 kV, 400 mA). The dose during one minute of videofluoroscopy was equivalent to the doses produced by one exposure in full-scale filming and three to four exposures in 100 mm filming. Although electronic magnification in 100 mm fluorography increases the doses by two or threefold, these are still less than the doses in full-scale radiography

The impact of confinement scaling on ITER [International Thermonuclear Experimental Reactor] parameters

International Nuclear Information System (INIS)

Reid, R.L.; Galambos, J.D.; Peng, Y.K.M.

1988-09-01

Energy confinement scaling is a major concern in the design of the International Thermonuclear Experimental Reactor (ITER). The existing database for tokamaks can be fitted with a number of different confinement scaling expressions that have similar degrees of approximation. These scaling laws predict confinement times for ITER that vary by over an order of magnitude. The uncertainties in the form and magnitude of these scaling laws must be substantially reduced before the plasma performance of ITER can be predicted with adequate reliability. The TETRA systems code is used to calculate the dependence of major ITER parameters on the scaling laws currently in use. Design constraints of interest in the present phase of ITER consideration are used, and the minimum-cost devices arising from these constraints are reviewed. 9 refs., 13 figs., 4 tabs

Spin theory of the density functional: reduced matrices and density functions

International Nuclear Information System (INIS)

Pavlov, R.; Delchev, Y.; Pavlova, K.; Maruani, J.

1993-01-01

Expressions for the reduced matrices and density functions of N-fermion systems of arbitrary order s (1<=s<=N) are derived within the frame of rigorous spin approach to the density functional theory (DFT). Using the local-scale transformation method and taking into account the particle spin it is shown that the reduced matrices and density functions are functionals of the total one-fermion density. Similar dependence is found for the distribution density of s-particle aggregates. Generalization and applicability of DFT to the case of s-particle ensembles and aggregates is discussed. 14 refs

A randomized control study of psychological intervention to reduce anxiety, amotivation and psychological distress among medical students.

Science.gov (United States)

Saravanan, Coumaravelou; Kingston, Rajiah

2014-05-01

Test anxiety aggravates psychological distress and reduces the motivation among graduate students. This study aimed to identify psychological intervention for test anxiety, which reduces the level of psychological distress, amotivation and increases the intrinsic and extrinsic motivation among medical students. Westside test anxiety scale, Kessler Perceived Stress Scale and Academic Motivation Scale were used to measure test anxiety, psychological distress and motivation on 436 1(st) year medical students. Out of 436 students, 74 students who exhibited moderate to high test anxiety were randomly divided into either experimental or waiting list group. In this true randomized experimental study, 32 participants from the intervention group received five sessions of psychological intervention consist of psychoeducation, relaxation therapy and systematic desensitization. Thirty-three students from waiting list received one session of advice and suggestions. After received psychological intervention participants from the intervention group experienced less anxiety, psychological distress, and amotivation (P < 0.01) and high intrinsic and extrinsic motivation (P < 0.01) in the postassessment compared with their preassessment scores. Overall psychological intervention is effective to reduce anxiety scores and its related variables.

Fatigue Assessment of Full-Scale Retrofitted Orthotropic Bridge Decks

NARCIS (Netherlands)

Teixeira De Freitas, S.; Kolstein, M.H.; Bijlaard, F.S.K.

2017-01-01

Full-scale fatigue tests were performed on two retrofitted orthotropic bridge decks (OBDs). The retrofitting systems consist of adding a second steel plate on the top of the existing deck. The aim is to reduce the stresses at the fatigue-sensitive details and therefore extend the fatigue life of

Technology demonstration for reducing mercury emissions from small-scale gold refining facilities.

Energy Technology Data Exchange (ETDEWEB)

Habegger, L. J.; Fernandez, L. E.; Engle, M.; Bailey, J. L.; Peterson, D. P.; MacDonell, M. M.; U.S. Environmental Protection Agency

2008-06-30

Gold that is brought from artisanal and small-scale gold mining areas to gold shops for processing and sale typically contains 5-40% mercury. The uncontrolled removal of the residual mercury in gold shops by using high-temperature evaporation can be a significant source of mercury emissions in urban areas where the shops are located. Emissions from gold shop hoods during a burn can exceed 1,000 mg/m{sup 3}. Because the saturation concentration of mercury vapor at operating temperatures at the hood exhaust is less than 100 mg/m{sup 3}, the dominant component of the exhaust is in the form of aerosol or liquid particles. The U.S. Environmental Protection Agency (EPA), with technical support from Argonne National Laboratory (Argonne), has completed a project to design and test a technology to remove the dominant aerosol component in the emissions from gold shops. The objective was to demonstrate a technology that could be manufactured at low cost and by using locally available materials and manufacturing capabilities. Six prototypes designed by Argonne were locally manufactured, installed, and tested in gold shops in Itaituba and Creporizao, Brazil. The initial prototype design incorporated a pebble bed as the media for collecting the mercury aerosols, and a mercury collection efficiency of over 90% was demonstrated. Though achieving high efficiencies, the initial prototype was determined to have practical disadvantages such as excessive weight, a somewhat complex construction, and high costs (>US$1,000). To further simplify the construction, operation, and associated costs, a second prototype design was developed in which the pebble bed was replaced with slotted steel baffle plates. The system was designed to have flexibility for installation in various hood configurations. The second prototype with the baffle plate design was installed and tested in several different hood/exhaust systems to determine the optimal installation configuration. The significance of

Scaling laws for gas–liquid flow in swirl vane separators

International Nuclear Information System (INIS)

Liu, Li; Bai, Bofeng

2016-01-01

Highlights: • Model for swirl vane separator performance is established with similarity criteria. • Scaling laws are developed to correlate downscale test with prototype separator. • Effects of key similarity criteria on separation performance are studied. • The vital role of droplet size distribution on separation performance is discussed. - Abstract: Laboratory tests on gas–liquid flow in swirl vane separators are usually carried out to help establish an experimental database for separator design and performance improvement. Such model tests are generally performed in the reduced scale and not on the actual working conditions. Though great efficiency is often obtainable in the reduced model, the performance of the full-sized prototype usually cannot be well predicted. To design downscale model tests and apply the experimental results to predict the prototype, a general relationship to correlate them is required. In this paper, the relation of the similitude-criterion concerning the pressure loss is presented by using the dimensionless analysis, and mathematical models for critical droplet diameter, grade efficiency and overall separation efficiency are established by analyzing the features of the droplet trajectory in gas swirling flow field. The essential similarity criteria accounting for pressure loss and separation efficiency are obtained, respectively. On this basis, the scaling laws which enable a comparison between the reduced model and the full-sized prototype under similar conditions are also developed. It is found that the overall separation efficiency is significantly affected by the size distribution of the small droplets, especially when the mean diameter is smaller than the critical droplet diameter.

Multi-GNSS PPP-RTK: From Large- to Small-Scale Networks

Directory of Open Access Journals (Sweden)

Nandakumaran Nadarajah

2018-04-01

Full Text Available Precise point positioning (PPP and its integer ambiguity resolution-enabled variant, PPP-RTK (real-time kinematic, can benefit enormously from the integration of multiple global navigation satellite systems (GNSS. In such a multi-GNSS landscape, the positioning convergence time is expected to be reduced considerably as compared to the one obtained by a single-GNSS setup. It is therefore the goal of the present contribution to provide numerical insights into the role taken by the multi-GNSS integration in delivering fast and high-precision positioning solutions (sub-decimeter and centimeter levels using PPP-RTK. To that end, we employ the Curtin PPP-RTK platform and process data-sets of GPS, BeiDou Navigation Satellite System (BDS and Galileo in stand-alone and combined forms. The data-sets are collected by various receiver types, ranging from high-end multi-frequency geodetic receivers to low-cost single-frequency mass-market receivers. The corresponding stations form a large-scale (Australia-wide network as well as a small-scale network with inter-station distances less than 30 km. In case of the Australia-wide GPS-only ambiguity-float setup, 90% of the horizontal positioning errors (kinematic mode are shown to become less than five centimeters after 103 min. The stated required time is reduced to 66 min for the corresponding GPS + BDS + Galieo setup. The time is further reduced to 15 min by applying single-receiver ambiguity resolution. The outcomes are supported by the positioning results of the small-scale network.

Reduction kinetics of Wüstite scale on pure iron and steel sheets in Ar and H

NARCIS (Netherlands)

Mao, W.; Sloof, W.G.

2017-01-01

A dense and closed Wüstite scale is formed on pure iron and Mn alloyed steel after oxidation in Ar + 33 vol pct CO₂ + 17 vol pct CO gas mixture. Reducing the Wüstite scale in Ar + H₂ gas mixture forms a dense and uniform iron layer on top of the remaining Wüstite scale,

Process engineering challenges of uranium extraction from phosphoric acid on industrial scale

International Nuclear Information System (INIS)

Mouriya, Govind; Singh, Dhirendra; Nath, A.K.; Majumdar, D.

2014-01-01

Heavy Water Board (HWB) is a constituent unit of the Department of Atomic Energy. One of the diversified activities undertaken by HWB is pursuing exploitation of non-conventional resources for recovery of uranium from wet phosphoric acid being the most prominent one. Amongst the feasible processes for recovery of uranium from phosphoric acid is solvent extraction. Use of in-house solvent produced by HWB, is another key driver. To garner necessary information for developing the industrial scale facilities, the process has been studied in the laboratory scale, mini scale, bench scale at Heavy Water Plant, Talcher. The process was subsequently scaled up to an industrial prototype scale unit and was set up as a Technology Demonstration Plant coupled with a commercial phosphoric acid plant. The plant has successfully processed more than 2 lakh m 3 of wet phosphoric acid and all the parameters including the product, Yellow Cake have been qualified. No adverse effect has been observed in the fertilizer produced. The main characteristics of the process and subsequent process innovations are discussed in this paper. These innovations have been carried out to overcome hurdles faced during commissioning and subsequent operations of the Plant. The innovations include improved pretreatment of the wet phosphoric acid for feeding to the extraction cycle, improved control of the first cycle chemical environment, reducing the strength of the phosphoric acid used for stripping, reducing the number of equipment and machineries, alteration in solvent composition used in the first and second cycle in the solvent extraction units of the plant. (author)

The effectiveness of psychoeducation and systematic desensitization to reduce test anxiety among first-year pharmacy students.

Science.gov (United States)

Rajiah, Kingston; Saravanan, Coumaravelou

2014-11-15

To analyze the effect of psychological intervention on reducing performance anxiety and the consequences of the intervention on first-year pharmacy students. In this experimental study, 236 first-year undergraduate pharmacy students from a private university in Malaysia were approached between weeks 5 and 7 of their first semester to participate in the study. The completed responses for the Westside Test Anxiety Scale (WTAS), the Kessler Perceived Distress Scale (PDS), and the Academic Motivation Scale (AMS) were received from 225 students. Out of 225 students, 42 exhibited moderate to high test anxiety according to the WTAS (score ranging from 30 to 39) and were randomly placed into either an experiment group (n=21) or a waiting list control group (n=21). The prevalence of test anxiety among pharmacy students in this study was lower compared to other university students in previous studies. The present study's anxiety management of psychoeducation and systematic education for test anxiety reduced lack of motivation and psychological distress and improved grade point average (GPA). Psychological intervention helped significantly reduce scores of test anxiety, psychological distress, and lack of motivation, and it helped improve students' GPA.

Highly Scalable Trip Grouping for Large Scale Collective Transportation Systems

DEFF Research Database (Denmark)

Gidofalvi, Gyozo; Pedersen, Torben Bach; Risch, Tore

2008-01-01

Transportation-related problems, like road congestion, parking, and pollution, are increasing in most cities. In order to reduce traffic, recent work has proposed methods for vehicle sharing, for example for sharing cabs by grouping "closeby" cab requests and thus minimizing transportation cost...... and utilizing cab space. However, the methods published so far do not scale to large data volumes, which is necessary to facilitate large-scale collective transportation systems, e.g., ride-sharing systems for large cities. This paper presents highly scalable trip grouping algorithms, which generalize previous...

Minimum scale controlled topology optimization and experimental test of a micro thermal actuator

DEFF Research Database (Denmark)

Heo, S.; Yoon, Gil Ho; Kim, Y.Y.

2008-01-01

This paper is concerned with the optimal topology design, fabrication and test of a micro thermal actuator. Because the minimum scale was controlled during the design optimization process, the production yield rate of the actuator was improved considerably; alternatively, the optimization design ...... tested. The test showed that control over the minimum length scale in the design process greatly improves the yield rate and reduces the performance deviation....... without scale control resulted in a very low yield rate. Using the minimum scale controlling topology design method developed earlier by the authors, micro thermal actuators were designed and fabricated through a MEMS process. Moreover, both their performance and production yield were experimentally...

Assessing the Efficiency of Small-Scale and Bottom Trawler Vessels in Greece

Directory of Open Access Journals (Sweden)

Dario Pinello

2016-07-01

Full Text Available This study explores the technical and scale efficiency of two types of Greek fishing vessels, small-scale vessels and bottom trawlers, using a bias-corrected input-oriented Data Envelopment Analysis model. Moreover, the associations between efficiency scores and vessel’s and skipper’s characteristics are also explored. The results indicate that small-scale vessels achieve a very low average technical efficiency score (0.42 but a much higher scale efficiency score (0.81. Conversely, bottom trawlers achieve lower scale but higher technical efficiency scores (0.68 and 0.73, respectively. One important finding of this study is that the technical efficiency of small-scale vessels, in contrast to trawlers, is positively associated with the experience of the skipper. In a looser context, it can be said that small-scale fisheries mainly rely on skill, whereas bottom trawlers rely more on technology. This study concludes that there is space for improvement in efficiency, mainly for small-scale vessels, which could allow the achievement of the same level of output by using reduced inputs.

Vanishing-Overhead Linear-Scaling Random Phase Approximation by Cholesky Decomposition and an Attenuated Coulomb-Metric.

Science.gov (United States)

Luenser, Arne; Schurkus, Henry F; Ochsenfeld, Christian

2017-04-11

A reformulation of the random phase approximation within the resolution-of-the-identity (RI) scheme is presented, that is competitive to canonical molecular orbital RI-RPA already for small- to medium-sized molecules. For electronically sparse systems drastic speedups due to the reduced scaling behavior compared to the molecular orbital formulation are demonstrated. Our reformulation is based on two ideas, which are independently useful: First, a Cholesky decomposition of density matrices that reduces the scaling with basis set size for a fixed-size molecule by one order, leading to massive performance improvements. Second, replacement of the overlap RI metric used in the original AO-RPA by an attenuated Coulomb metric. Accuracy is significantly improved compared to the overlap metric, while locality and sparsity of the integrals are retained, as is the effective linear scaling behavior.

Green smartphone GPUs: Optimizing energy consumption using GPUFreq scaling governors

KAUST Repository

Ahmad, Enas M.

2015-10-19

Modern smartphones are limited by their short battery life. The advancement of the graphical performance is considered as one of the main reasons behind the massive battery drainage in smartphones. In this paper we present a novel implementation of the GPUFreq Scaling Governors, a Dynamic Voltage and Frequency Scaling (DVFS) model implemented in the Android Linux kernel for dynamically scaling smartphone Graphical Processing Units (GPUs). The GPUFreq governors offer users multiple variations and alternatives in controlling the power consumption and performance of their GPUs. We implemented and evaluated our model on a smartphone GPU and measured the energy performance using an external power monitor. The results show that the energy consumption of smartphone GPUs can be significantly reduced with a minor effect on the GPU performance.

A 100,000 Scale Factor Radar Range.

Science.gov (United States)

Blanche, Pierre-Alexandre; Neifeld, Mark; Peyghambarian, Nasser

2017-12-19

The radar cross section of an object is an important electromagnetic property that is often measured in anechoic chambers. However, for very large and complex structures such as ships or sea and land clutters, this common approach is not practical. The use of computer simulations is also not viable since it would take many years of computational time to model and predict the radar characteristics of such large objects. We have now devised a new scaling technique to overcome these difficulties, and make accurate measurements of the radar cross section of large items. In this article we demonstrate that by reducing the scale of the model by a factor 100,000, and using near infrared wavelength, the radar cross section can be determined in a tabletop setup. The accuracy of the method is compared to simulations, and an example of measurement is provided on a 1 mm highly detailed model of a ship. The advantages of this scaling approach is its versatility, and the possibility to perform fast, convenient, and inexpensive measurements.

The biomechanical demands of manual scaling on the shoulders & neck of dental hygienists.

Science.gov (United States)

La Delfa, Nicholas J; Grondin, Diane E; Cox, Jocelyn; Potvin, Jim R; Howarth, Samuel J

2017-01-01

The purpose of this study was to evaluate the postural and muscular demands placed on the shoulders and neck of dental hygienists when performing a simulated manual scaling task. Nineteen healthy female dental hygienists performed 30-min of simulated manual scaling on a manikin head in a laboratory setting. Surface electromyography was used to monitor muscle activity from several neck and shoulder muscles, and neck and arm elevation kinematics were evaluated using motion capture. The simulated scaling task resulted in a large range of neck and arm elevation angles and excessive low-level muscular demands in the neck extensor and scapular stabilising muscles. The physical demands varied depending on the working position of the hygienists relative to the manikin head. These findings are valuable in guiding future ergonomics interventions aimed at reducing the physical exposures of dental hygiene work. Practitioner Summary: Given that this study evaluates the physical demands of manual scaling, a procedure that is fundamental to dental hygiene work, the findings are valuable to identify ergonomics interventions to reduce the prevalence of work-related injuries, disability and the potential for early retirement among this occupational group.

Multidisciplinary Conceptual Design for Reduced-Emission Rotorcraft

Science.gov (United States)

Silva, Christopher; Johnson, Wayne; Solis, Eduardo

2018-01-01

Python-based wrappers for OpenMDAO are used to integrate disparate software for practical conceptual design of rotorcraft. The suite of tools which are connected thus far include aircraft sizing, comprehensive analysis, and parametric geometry. The tools are exercised to design aircraft with aggressive goals for emission reductions relative to fielded state-of-the-art rotorcraft. Several advanced reduced-emission rotorcraft are designed and analyzed, demonstrating the flexibility of the tools to consider a wide variety of potentially transformative vertical flight vehicles. To explore scale effects, aircraft have been sized for 5, 24, or 76 passengers in their design missions. Aircraft types evaluated include tiltrotor, single-main-rotor, coaxial, and side-by-side helicopters. Energy and drive systems modeled include Lithium-ion battery, hydrogen fuel cell, turboelectric hybrid, and turboshaft drive systems. Observations include the complex nature of the trade space for this simple problem, with many potential aircraft design and operational solutions for achieving significant emission reductions. Also interesting is that achieving greatly reduced emissions may not require exotic component technologies, but may be achieved with a dedicated design objective of reducing emissions.

Reducing gravity takes the bounce out of running.

Science.gov (United States)

Polet, Delyle T; Schroeder, Ryan T; Bertram, John E A

2018-02-13

In gravity below Earth-normal, a person should be able to take higher leaps in running. We asked 10 subjects to run on a treadmill in five levels of simulated reduced gravity and optically tracked centre-of-mass kinematics. Subjects consistently reduced ballistic height compared with running in normal gravity. We explain this trend by considering the vertical take-off velocity (defined as maximum vertical velocity). Energetically optimal gaits should balance the energetic costs of ground-contact collisions (favouring lower take-off velocity), and step frequency penalties such as leg swing work (favouring higher take-off velocity, but less so in reduced gravity). Measured vertical take-off velocity scaled with the square root of gravitational acceleration, following energetic optimality predictions and explaining why ballistic height decreases in lower gravity. The success of work-based costs in predicting this behaviour challenges the notion that gait adaptation in reduced gravity results from an unloading of the stance phase. Only the relationship between take-off velocity and swing cost changes in reduced gravity; the energetic cost of the down-to-up transition for a given vertical take-off velocity does not change with gravity. Because lower gravity allows an elongated swing phase for a given take-off velocity, the motor control system can relax the vertical momentum change in the stance phase, thus reducing ballistic height, without great energetic penalty to leg swing work. Although it may seem counterintuitive, using less 'bouncy' gaits in reduced gravity is a strategy to reduce energetic costs, to which humans seem extremely sensitive. © 2018. Published by The Company of Biologists Ltd.

Wafer integrated micro-scale concentrating photovoltaics

Science.gov (United States)

Gu, Tian; Li, Duanhui; Li, Lan; Jared, Bradley; Keeler, Gordon; Miller, Bill; Sweatt, William; Paap, Scott; Saavedra, Michael; Das, Ujjwal; Hegedus, Steve; Tauke-Pedretti, Anna; Hu, Juejun

2017-09-01

Recent development of a novel micro-scale PV/CPV technology is presented. The Wafer Integrated Micro-scale PV approach (WPV) seamlessly integrates multijunction micro-cells with a multi-functional silicon platform that provides optical micro-concentration, hybrid photovoltaic, and mechanical micro-assembly. The wafer-embedded micro-concentrating elements is shown to considerably improve the concentration-acceptance-angle product, potentially leading to dramatically reduced module materials and fabrication costs, sufficient angular tolerance for low-cost trackers, and an ultra-compact optical architecture, which makes the WPV module compatible with commercial flat panel infrastructures. The PV/CPV hybrid architecture further allows the collection of both direct and diffuse sunlight, thus extending the geographic and market domains for cost-effective PV system deployment. The WPV approach can potentially benefits from both the high performance of multijunction cells and the low cost of flat plate Si PV systems.

Refinement of the Brazilian Household Food Insecurity Measurement Scale: Recommendation for a 14-item EBIA

Directory of Open Access Journals (Sweden)

Ana Maria Segall-Corrêa

2014-04-01

Full Text Available OBJECTIVE: To review and refine Brazilian Household Food Insecurity Measurement Scale structure. METHODS: The study analyzed the impact of removing the item "adult lost weight" and one of two possibly redundant items on Brazilian Household Food Insecurity Measurement Scale psychometric behavior using the one-parameter logistic (Rasch model. Brazilian Household Food Insecurity Measurement Scale psychometric behavior was analyzed with respect to acceptable adjustment values ranging from 0.7 to 1.3, and to severity scores of the items with theoretically expected gradients. The socioeconomic and food security indicators came from the 2004 National Household Sample Survey, which obtained complete answers to Brazilian Household Food Insecurity Measurement Scale items from 112,665 households. RESULTS: Removing the items "adult reduced amount..." followed by "adult ate less..." did not change the infit of the remaining items, except for "adult lost weight", whose infit increased from 1.21 to 1.56. The internal consistency and item severity scores did not change when "adult ate less" and one of the two redundant items were removed. CONCLUSION: Brazilian Household Food Insecurity Measurement Scale reanalysis reduced the number of scale items from 16 to 14 without changing its internal validity. Its use as a nationwide household food security measure is strongly recommended.

Is it more effective group relaxation than individual to reduce anxiety in specific phobias?

Directory of Open Access Journals (Sweden)

Julián Carretero Román

2009-05-01

Full Text Available Relaxation is a standard technique used by nurses to reduce the level of anxiety. It seems that their implementation on a group can bring certain benefits compared with individual relaxation. This outline is intended to raise this hypothesis in caring for individuals diagnosed with specific phobia, by approaching the problem from the cognitive behavioural therapy perspective. In addition, it seeks to evaluate the usefulness of the nurse intervention relaxation to reduce the level of anxiety, in turn comparing the results obtained using an indicator of the scale of results NOC and the Hamilton Anxiety Scale. The phobia is a specific entity underdiagnosed, whose prevalence is about 10%. Those affected can live a really limited and debilitating, deteriorating quality of life. The community mental health nurses are in a unique position to participate in the cognitive behavioural therapy through relaxation, which will allow them to reduce the level of anxiety when people establish contact with the phobic stimulus. Methodology: quasi-experimental study in specific phobia diagnosed, 20 to 40 years old adults attending for the first time to the mental health facility derived from primary care. Both the control group as the pilot will be treated by conducted cognitive-behavioural psychotherapy individualized according to the therapeutic protocol MSC, except in terms of relaxation, which in the experimental group will be conducted at the group level. The effectiveness of treatment will be assessed with the Hamilton anxiety scale and the likert type scale of outcome indicators NOC "stress level" with 3 measurements, before starting, immediately after completing the sessions of relaxation and three months later, checking the decline in the average level of anxiety.

Geometrical scaling in charm structure function ratios

International Nuclear Information System (INIS)

Boroun, G.R.; Rezaei, B.

2014-01-01

By using a Laplace-transform technique, we solve the next-to-leading-order master equation for charm production and derive a compact formula for the ratio R c =F L cc ¯ /F 2 cc ¯ , which is useful for extracting the charm structure function from the reduced charm cross section, in particular, at DESY HERA, at small x. Our results show that this ratio is independent of x at small x. In this method of determining the ratios, we apply geometrical scaling in charm production in deep inelastic scattering (DIS). Our analysis shows that the renormalization scales have a sizable impact on the ratio R c at high Q 2 . Our results for the ratio of the charm structure functions are in a good agreement with some phenomenological models

Cross-validating a bidimensional mathematics anxiety scale.

Science.gov (United States)

Haiyan Bai

2011-03-01

The psychometric properties of a 14-item bidimensional Mathematics Anxiety Scale-Revised (MAS-R) were empirically cross-validated with two independent samples consisting of 647 secondary school students. An exploratory factor analysis on the scale yielded strong construct validity with a clear two-factor structure. The results from a confirmatory factor analysis indicated an excellent model-fit (χ(2) = 98.32, df = 62; normed fit index = .92, comparative fit index = .97; root mean square error of approximation = .04). The internal consistency (.85), test-retest reliability (.71), interfactor correlation (.26, p anxiety. Math anxiety, as measured by MAS-R, correlated negatively with student achievement scores (r = -.38), suggesting that MAS-R may be a useful tool for classroom teachers and other educational personnel tasked with identifying students at risk of reduced math achievement because of anxiety.

Scaling up HIV viral load - lessons from the large-scale implementation of HIV early infant diagnosis and CD4 testing.

Science.gov (United States)

Peter, Trevor; Zeh, Clement; Katz, Zachary; Elbireer, Ali; Alemayehu, Bereket; Vojnov, Lara; Costa, Alex; Doi, Naoko; Jani, Ilesh

2017-11-01

The scale-up of effective HIV viral load (VL) testing is an urgent public health priority. Implementation of testing is supported by the availability of accurate, nucleic acid based laboratory and point-of-care (POC) VL technologies and strong WHO guidance recommending routine testing to identify treatment failure. However, test implementation faces challenges related to the developing health systems in many low-resource countries. The purpose of this commentary is to review the challenges and solutions from the large-scale implementation of other diagnostic tests, namely nucleic-acid based early infant HIV diagnosis (EID) and CD4 testing, and identify key lessons to inform the scale-up of VL. Experience with EID and CD4 testing provides many key lessons to inform VL implementation and may enable more effective and rapid scale-up. The primary lessons from earlier implementation efforts are to strengthen linkage to clinical care after testing, and to improve the efficiency of testing. Opportunities to improve linkage include data systems to support the follow-up of patients through the cascade of care and test delivery, rapid sample referral networks, and POC tests. Opportunities to increase testing efficiency include improvements to procurement and supply chain practices, well connected tiered laboratory networks with rational deployment of test capacity across different levels of health services, routine resource mapping and mobilization to ensure adequate resources for testing programs, and improved operational and quality management of testing services. If applied to VL testing programs, these approaches could help improve the impact of VL on ART failure management and patient outcomes, reduce overall costs and help ensure the sustainable access to reduced pricing for test commodities, as well as improve supportive health systems such as efficient, and more rigorous quality assurance. These lessons draw from traditional laboratory practices as well as fields

Scaling Analysis of the Single-Phase Natural Circulation: the Hydraulic Similarity

International Nuclear Information System (INIS)

Yu, Xin-Guo; Choi, Ki-Yong

2015-01-01

These passive safety systems all rely on the natural circulation to cool down the reactor cores during an accident. Thus, a robust and accurate scaling methodology must be developed and employed to both assist in the design of a scaled-down test facility and guide the tests in order to mimic the natural circulation flow of its prototype. The natural circulation system generally consists of a heat source, the connecting pipes and several heat sinks. Although many applauding scaling methodologies have been proposed during last several decades, few works have been dedicated to systematically analyze and exactly preserve the hydraulic similarity. In the present study, the hydraulic similarity analyses are performed at both system and local level. By this mean, the scaling criteria for the exact hydraulic similarity in a full-pressure model have been sought. In other words, not only the system-level but also the local-level hydraulic similarities are pursued. As the hydraulic characteristics of a fluid system is governed by the momentum equation, the scaling analysis starts with it. A dimensionless integral loop momentum equation is derived to obtain the dimensionless numbers. In the dimensionless momentum equation, two dimensionless numbers, the dimensionless flow resistance number and the dimensionless gravitational force number, are identified along with a unique hydraulic time scale, characterizing the system hydraulic response. A full-height full-pressure model is also made to see which model among the full-height model and reduced-height model can preserve the hydraulic behavior of the prototype. From the dimensionless integral momentum equation, a unique hydraulic time scale, which characterizes the hydraulic response of a single-phase natural circulation system, is identified along with two dimensionless parameters: the dimensionless flow resistance number and the dimensionless gravitational force number. By satisfying the equality of both dimensionless numbers

Scaling Analysis of the Single-Phase Natural Circulation: the Hydraulic Similarity

Energy Technology Data Exchange (ETDEWEB)

Yu, Xin-Guo; Choi, Ki-Yong [KAERI, Daejeon (Korea, Republic of)

2015-05-15

These passive safety systems all rely on the natural circulation to cool down the reactor cores during an accident. Thus, a robust and accurate scaling methodology must be developed and employed to both assist in the design of a scaled-down test facility and guide the tests in order to mimic the natural circulation flow of its prototype. The natural circulation system generally consists of a heat source, the connecting pipes and several heat sinks. Although many applauding scaling methodologies have been proposed during last several decades, few works have been dedicated to systematically analyze and exactly preserve the hydraulic similarity. In the present study, the hydraulic similarity analyses are performed at both system and local level. By this mean, the scaling criteria for the exact hydraulic similarity in a full-pressure model have been sought. In other words, not only the system-level but also the local-level hydraulic similarities are pursued. As the hydraulic characteristics of a fluid system is governed by the momentum equation, the scaling analysis starts with it. A dimensionless integral loop momentum equation is derived to obtain the dimensionless numbers. In the dimensionless momentum equation, two dimensionless numbers, the dimensionless flow resistance number and the dimensionless gravitational force number, are identified along with a unique hydraulic time scale, characterizing the system hydraulic response. A full-height full-pressure model is also made to see which model among the full-height model and reduced-height model can preserve the hydraulic behavior of the prototype. From the dimensionless integral momentum equation, a unique hydraulic time scale, which characterizes the hydraulic response of a single-phase natural circulation system, is identified along with two dimensionless parameters: the dimensionless flow resistance number and the dimensionless gravitational force number. By satisfying the equality of both dimensionless numbers

BioPig: a Hadoop-based analytic toolkit for large-scale sequence data.

Science.gov (United States)

Nordberg, Henrik; Bhatia, Karan; Wang, Kai; Wang, Zhong

2013-12-01

The recent revolution in sequencing technologies has led to an exponential growth of sequence data. As a result, most of the current bioinformatics tools become obsolete as they fail to scale with data. To tackle this 'data deluge', here we introduce the BioPig sequence analysis toolkit as one of the solutions that scale to data and computation. We built BioPig on the Apache's Hadoop MapReduce system and the Pig data flow language. Compared with traditional serial and MPI-based algorithms, BioPig has three major advantages: first, BioPig's programmability greatly reduces development time for parallel bioinformatics applications; second, testing BioPig with up to 500 Gb sequences demonstrates that it scales automatically with size of data; and finally, BioPig can be ported without modification on many Hadoop infrastructures, as tested with Magellan system at National Energy Research Scientific Computing Center and the Amazon Elastic Compute Cloud. In summary, BioPig represents a novel program framework with the potential to greatly accelerate data-intensive bioinformatics analysis.

Pore-scale uncertainty quantification with multilevel Monte Carlo

KAUST Repository

Icardi, Matteo

2014-01-06

Computational fluid dynamics (CFD) simulations of pore-scale transport processes in porous media have recently gained large popularity. However the geometrical details of the pore structures can be known only in a very low number of samples and the detailed flow computations can be carried out only on a limited number of cases. The explicit introduction of randomness in the geometry and in other setup parameters can be crucial for the optimization of pore-scale investigations for random homogenization. Since there are no generic ways to parametrize the randomness in the porescale structures, Monte Carlo techniques are the most accessible to compute statistics. We propose a multilevel Monte Carlo (MLMC) technique to reduce the computational cost of estimating quantities of interest within a prescribed accuracy constraint. Random samples of pore geometries with a hierarchy of geometrical complexities and grid refinements, are synthetically generated and used to propagate the uncertainties in the flow simulations and compute statistics of macro-scale effective parameters.

Development and Examination of Personal and Social Responsibility Behaviors Scale

Directory of Open Access Journals (Sweden)

Bijen FİLİZ

2018-03-01

Full Text Available In this study, “Personal and Social Responsibility Behaviors Scale (PSRB-S” was developed in order to determine students’ responsibility behaviors in accordance with “Personal and Social Responsibility” model developed by Don Hellison and students’ personal and social responsibility levels were examined in terms of gender, age and years of sport practice through this scale. Pertaining to personal and social dimension of responsibility, four-category Likert type trial scale consisting of 52 items and Exploratory Factor Analysis (EFA were applied to 330 high-school students. Items that did not apply as a result of the analysis were omitted from 52-item trial scale and the scale was reduced to 14 items. A final scale consisting of two factors was created. Obtained scale was applied to different 250 high-school students for Confirmatory Factor Analysis (CFA. It has been determined that EFA and CFA results of two-factor PSRB-S and reliability and validity of internal consistency coefficients are at an acceptable level. It was not detected a significance difference in total scores of athlete students’ responsibility behaviors in terms of gender and age variables while there were significant difference in their total scores of years of sport practice.

[Ice application for reducing pain associated with goserelin acetate injection].

Science.gov (United States)

Ishii, Kaname; Nagata, Chika; Koshizaki, Eiko; Nishiuchi, Satoko

2013-10-01

We investigated the effectiveness of using an ice pack for reducing the pain associated with goserelin acetate injection. In this study, 39 patients with prostate cancer and 1 patient with breast cancer receiving hormonal therapy with goserelin acetate were enrolled. All patients completed a questionnaire regarding the use of ice application. We used the numerical rating scale (NRS) to assess the pain associated with injection. The NRS scores indicated that the pain was significantly less with ice application than with the usual method (p application could decrease the duration of pain sensation. Ice application at the injection site is safe and effective for reducing pain.

Reduced uncertainty of regional scale CLM predictions of net carbon fluxes and leaf area indices with estimated plant-specific parameters

Science.gov (United States)

Post, Hanna; Hendricks Franssen, Harrie-Jan; Han, Xujun; Baatz, Roland; Montzka, Carsten; Schmidt, Marius; Vereecken, Harry

2016-04-01

Reliable estimates of carbon fluxes and states at regional scales are required to reduce uncertainties in regional carbon balance estimates and to support decision making in environmental politics. In this work the Community Land Model version 4.5 (CLM4.5-BGC) was applied at a high spatial resolution (1 km2) for the Rur catchment in western Germany. In order to improve the model-data consistency of net ecosystem exchange (NEE) and leaf area index (LAI) for this study area, five plant functional type (PFT)-specific CLM4.5-BGC parameters were estimated with time series of half-hourly NEE data for one year in 2011/2012, using the DiffeRential Evolution Adaptive Metropolis (DREAM) algorithm, a Markov Chain Monte Carlo (MCMC) approach. The parameters were estimated separately for four different plant functional types (needleleaf evergreen temperate tree, broadleaf deciduous temperate tree, C3-grass and C3-crop) at four different sites. The four sites are located inside or close to the Rur catchment. We evaluated modeled NEE for one year in 2012/2013 with NEE measured at seven eddy covariance sites in the catchment, including the four parameter estimation sites. Modeled LAI was evaluated by means of LAI derived from remotely sensed RapidEye images of about 18 days in 2011/2012. Performance indices were based on a comparison between measurements and (i) a reference run with CLM default parameters, and (ii) a 60 instance CLM ensemble with parameters sampled from the DREAM posterior probability density functions (pdfs). The difference between the observed and simulated NEE sum reduced 23% if estimated parameters instead of default parameters were used as input. The mean absolute difference between modeled and measured LAI was reduced by 59% on average. Simulated LAI was not only improved in terms of the absolute value but in some cases also in terms of the timing (beginning of vegetation onset), which was directly related to a substantial improvement of the NEE estimates in

Large scale particle simulations in a virtual memory computer

International Nuclear Information System (INIS)

Gray, P.C.; Million, R.; Wagner, J.S.; Tajima, T.

1983-01-01

Virtual memory computers are capable of executing large-scale particle simulations even when the memory requirements exceeds the computer core size. The required address space is automatically mapped onto slow disc memory the the operating system. When the simulation size is very large, frequent random accesses to slow memory occur during the charge accumulation and particle pushing processes. Assesses to slow memory significantly reduce the excecution rate of the simulation. We demonstrate in this paper that with the proper choice of sorting algorithm, a nominal amount of sorting to keep physically adjacent particles near particles with neighboring array indices can reduce random access to slow memory, increase the efficiency of the I/O system, and hence, reduce the required computing time. (orig.)

Large-scale particle simulations in a virtual-memory computer

International Nuclear Information System (INIS)

Gray, P.C.; Wagner, J.S.; Tajima, T.; Million, R.

1982-08-01

Virtual memory computers are capable of executing large-scale particle simulations even when the memory requirements exceed the computer core size. The required address space is automatically mapped onto slow disc memory by the operating system. When the simulation size is very large, frequent random accesses to slow memory occur during the charge accumulation and particle pushing processes. Accesses to slow memory significantly reduce the execution rate of the simulation. We demonstrate in this paper that with the proper choice of sorting algorithm, a nominal amount of sorting to keep physically adjacent particles near particles with neighboring array indices can reduce random access to slow memory, increase the efficiency of the I/O system, and hence, reduce the required computing time

Dual-scale topology optoelectronic processor.

Science.gov (United States)

Marsden, G C; Krishnamoorthy, A V; Esener, S C; Lee, S H

1991-12-15

The dual-scale topology optoelectronic processor (D-STOP) is a parallel optoelectronic architecture for matrix algebraic processing. The architecture can be used for matrix-vector multiplication and two types of vector outer product. The computations are performed electronically, which allows multiplication and summation concepts in linear algebra to be generalized to various nonlinear or symbolic operations. This generalization permits the application of D-STOP to many computational problems. The architecture uses a minimum number of optical transmitters, which thereby reduces fabrication requirements while maintaining area-efficient electronics. The necessary optical interconnections are space invariant, minimizing space-bandwidth requirements.

Cross-scale modelling of the climate-change mitigation potential of biochar systems: Global implications of nano-scale processes

Science.gov (United States)

Woolf, Dominic; Lehmann, Johannes

2014-05-01

With CO2 emissions still tracking the upper bounds of projected emissions scenarios, it is becoming increasingly urgent to reduce net greenhouse gas (GHG) emissions, and increasingly likely that restricting future atmospheric GHG concentrations to within safe limits will require an eventual transition towards net negative GHG emissions. Few measures capable of providing negative emissions at a globally-significant scale are currently known. Two that are most often considered include carbon sequestration in biomass and soil, and biomass energy with carbon capture and storage (BECCS). In common with these two approaches, biochar also relies on the use of photosynthetically-bound carbon in biomass. But, because biomass and land are limited, it is critical that these resources are efficiently allocated between biomass/soil sequestration, bioenergy, BECCS, biochar, and other competing uses such as food, fiber and biodiversity. In many situations, biochar can offer advantages that may make it the preferred use of a limited biomass supply. These advantages include that: 1) Biochar can provide valuable benefits to agriculture by improving soil fertility and crop production, and reducing fertlizer and irrigation requirements. 2) Biochar is significantly more stable than biomass or other forms of soil carbon, thus lowering the risk of future losses compared to sequestration in biomass or soil organic carbon. 3) Gases and volatiles produced by pyrolysis can be combusted for energy (which may offset fossil fuel emissions). 4) Biochar can further lower GHG emissions by reducing nitrous oxide emissions from soil and by enhancing net primary production. Determining the optimal use of biomass requires that we are able to model not only the climate-change mitigation impact of each option, but also their economic and wider environmental impacts. Thus, what is required is a systems modelling approach that integrates components representing soil biogeochemistry, hydrology, crop

Conformal-Based Surface Morphing and Multi-Scale Representation

Directory of Open Access Journals (Sweden)

Ka Chun Lam

2014-05-01

Full Text Available This paper presents two algorithms, based on conformal geometry, for the multi-scale representations of geometric shapes and surface morphing. A multi-scale surface representation aims to describe a 3D shape at different levels of geometric detail, which allows analyzing or editing surfaces at the global or local scales effectively. Surface morphing refers to the process of interpolating between two geometric shapes, which has been widely applied to estimate or analyze deformations in computer graphics, computer vision and medical imaging. In this work, we propose two geometric models for surface morphing and multi-scale representation for 3D surfaces. The basic idea is to represent a 3D surface by its mean curvature function, H, and conformal factor function λ, which uniquely determine the geometry of the surface according to Riemann surface theory. Once we have the (λ, H parameterization of the surface, post-processing of the surface can be done directly on the conformal parameter domain. In particular, the problem of multi-scale representations of shapes can be reduced to the signal filtering on the λ and H parameters. On the other hand, the surface morphing problem can be transformed to an interpolation process of two sets of (λ, H parameters. We test the proposed algorithms on 3D human face data and MRI-derived brain surfaces. Experimental results show that our proposed methods can effectively obtain multi-scale surface representations and give natural surface morphing results.

Sparing land for biodiversity at multiple spatial scales

Directory of Open Access Journals (Sweden)

Johan eEkroos

2016-01-01

Full Text Available A common approach to the conservation of farmland biodiversity and the promotion of multifunctional landscapes, particularly in landscapes containing only small remnants of non-crop habitats, has been to maintain landscape heterogeneity and reduce land-use intensity. In contrast, it has recently been shown that devoting specific areas of non-crop habitats to conservation, segregated from high-yielding farmland (‘land sparing’, can more effectively conserve biodiversity than promoting low-yielding, less intensively managed farmland occupying larger areas (‘land sharing’. In the present paper we suggest that the debate over the relative merits of land sparing or land sharing is partly blurred by the differing spatial scales at which it is suggested that land sparing should be applied. We argue that there is no single correct spatial scale for segregating biodiversity protection and commodity production in multifunctional landscapes. Instead we propose an alternative conceptual construct, which we call ‘multiple-scale land sparing’, targeting biodiversity and ecosystem services in transformed landscapes. We discuss how multiple-scale land sparing may overcome the apparent dichotomy between land sharing and land sparing and help to find acceptable compromises that conserve biodiversity and landscape multifunctionality.

Reduced-rank approximations to the far-field transform in the gridded fast multipole method

Science.gov (United States)

Hesford, Andrew J.; Waag, Robert C.

2011-05-01

The fast multipole method (FMM) has been shown to have a reduced computational dependence on the size of finest-level groups of elements when the elements are positioned on a regular grid and FFT convolution is used to represent neighboring interactions. However, transformations between plane-wave expansions used for FMM interactions and pressure distributions used for neighboring interactions remain significant contributors to the cost of FMM computations when finest-level groups are large. The transformation operators, which are forward and inverse Fourier transforms with the wave space confined to the unit sphere, are smooth and well approximated using reduced-rank decompositions that further reduce the computational dependence of the FMM on finest-level group size. The adaptive cross approximation (ACA) is selected to represent the forward and adjoint far-field transformation operators required by the FMM. However, the actual error of the ACA is found to be greater than that predicted using traditional estimates, and the ACA generally performs worse than the approximation resulting from a truncated singular-value decomposition (SVD). To overcome these issues while avoiding the cost of a full-scale SVD, the ACA is employed with more stringent accuracy demands and recompressed using a reduced, truncated SVD. The results show a greatly reduced approximation error that performs comparably to the full-scale truncated SVD without degrading the asymptotic computational efficiency associated with ACA matrix assembly.

Sustainability effects of household-scale biogas in rural China

International Nuclear Information System (INIS)

Gosens, Jorrit; Lu, Yonglong; He, Guizhen; Bluemling, Bettina; Beckers, Theo A.M.

2013-01-01

Households in rural China rely heavily on low quality fuels which results in reduced quality of life and environmental degradation. This study assesses the comparative contribution of household scale biogas installations to the broad set of sustainability objectives in the Chinese biogas policy framework, which targets household budget, fuel collection workload, forest degradation, indoor air quality and health, renewable energy supply, and climate change. A household survey was used to determine how biogas affected consumption levels of crop residues, fuel wood, coal, LPG, and electricity. Biogas users were found to reduce consumption of biomass fuels but not coal. Although LPG is not a highly commonly used fuel in rural China, biogas users nearly cease to use it altogether. A big reduction in fuel wood consumption results in strongly reduced workload and forest degradation. Although household scale biogas has alleviated all sustainability issues targeted by Chinese policies, low quality fuel use remains abundant, even in households using biogas. Continued promotion of the construction of biogas installations is advisable, but additional policies are needed to ensure higher quality heating energy supply and cleaner uses of biomass fuels. - Highlights: ► Household biogas alleviated all sustainability issues targeted by policy. ► Biogas users consume less biomass fuels, much less LPG, but similar amounts of coal. ► Strongest sustainability effects are reduced workload and forest degradation. ► Household budget effects are slight as commercial cooking fuel use is limited. ► Low quality fuel use remains abundant and further policy efforts are needed

Full-Scale Approximations of Spatio-Temporal Covariance Models for Large Datasets

KAUST Repository

Zhang, Bohai; Sang, Huiyan; Huang, Jianhua Z.

2014-01-01

of dataset and application of such models is not feasible for large datasets. This article extends the full-scale approximation (FSA) approach by Sang and Huang (2012) to the spatio-temporal context to reduce computational complexity. A reversible jump Markov

Can large-scale oblique undulations on a solid wall reduce the turbulent drag?

Science.gov (United States)

Ghebali, Sacha; Chernyshenko, Sergei I.; Leschziner, Michael A.

2017-10-01

Direct numerical simulations of fully developed turbulent channel flows with wavy walls are undertaken. The wavy walls, skewed with respect to the mean flow direction, are introduced as a means of emulating a Spatial Stokes Layer (SSL) induced by in-plane wall motion. The transverse shear strain above the wavy wall is shown to be similar to that of a SSL, thereby affecting the turbulent flow and leading to a reduction in the turbulent skin-friction drag. However, some important differences with respect to the SSL case are brought to light too. In particular, the phase variations of the turbulent properties are accentuated and, unlike in the SSL case, there is a region of increased turbulence production over a portion of the wall, above the leeward side of the wave, thus giving rise to a local increase in dissipation. The pressure- and friction-drag levels are carefully quantified for various flow configurations, exhibiting a combined maximum overall-drag reduction of about 0.6%. The friction-drag reduction is shown to behave approximately quadratically for small wave slopes and then linearly for higher slopes, whilst the pressure-drag penalty increases quadratically. The transverse shear-strain layer is shown to be approximately Reynolds-number independent when the wave geometry is scaled in wall units.

Linear-scaling evaluation of the local energy in quantum Monte Carlo

International Nuclear Information System (INIS)

Austin, Brian; Aspuru-Guzik, Alan; Salomon-Ferrer, Romelia; Lester, William A. Jr.

2006-01-01

For atomic and molecular quantum Monte Carlo calculations, most of the computational effort is spent in the evaluation of the local energy. We describe a scheme for reducing the computational cost of the evaluation of the Slater determinants and correlation function for the correlated molecular orbital (CMO) ansatz. A sparse representation of the Slater determinants makes possible efficient evaluation of molecular orbitals. A modification to the scaled distance function facilitates a linear scaling implementation of the Schmidt-Moskowitz-Boys-Handy (SMBH) correlation function that preserves the efficient matrix multiplication structure of the SMBH function. For the evaluation of the local energy, these two methods lead to asymptotic linear scaling with respect to the molecule size

Scale-up of Escherichia coli growth and recombinant protein expression conditions from microwell to laboratory and pilot scale based on matched k(L)a.

Science.gov (United States)

Islam, R S; Tisi, D; Levy, M S; Lye, G J

2008-04-01

Fermentation optimization experiments are ideally performed at small scale to reduce time, cost and resource requirements. Currently microwell plates (MWPs) are under investigation for this purpose as the format is ideally suited to automated high-throughput experimentation. In order to translate an optimized small-scale fermentation process to laboratory and pilot scale stirred-tank reactors (STRs) it is necessary to characterize key engineering parameters at both scales given the differences in geometry and the mechanisms of aeration and agitation. In this study oxygen mass transfer coefficients are determined in three MWP formats and in 7.5 L and 75 L STRs. k(L)a values were determined in cell-free media using the dynamic gassing-out technique over a range of agitation conditions. Previously optimized culture conditions at the MWP scale were then scaled up to the larger STR scales on the basis of matched k(L)a values. The accurate reproduction of MWP (3 mL) E. coli BL21 (DE3) culture kinetics at the two larger scales was shown in terms of cell growth, protein expression, and substrate utilization for k(L)a values that provided effective mixing and gas-liquid distribution at each scale. This work suggests that k(L)a provides a useful initial scale-up criterion for MWP culture conditions which enabled a 15,000-fold scale translation in this particular case. This work complements our earlier studies on the application of DoE techniques to MWP fermentation optimization and in so doing provides a generic framework for the generation of large quantities of soluble protein in a rapid and cost-effective manner.

Vermicomposting as a technology for reducing nitrogen losses and greenhouse gas emissions from small-scale composting

NARCIS (Netherlands)

Nigussie, Abebe; Kuijper, Thomas; Bruun, Sander; Neergaard, de Andreas

2016-01-01

Thermophilic composting produces a significant amount of greenhouse gases. The objectives of this study were (i) to evaluate the effectiveness of vermicomposting to reduce nitrogen losses and greenhouse gases emissions compared to thermophilic composting, and (ii) to determine the effect of

Framing scales and scaling frames

NARCIS (Netherlands)

van Lieshout, M.; Dewulf, A.; Aarts, N.; Termeer, K.

2009-01-01

Policy problems are not just out there. Actors highlight different aspects of a situation as problematic and situate the problem on different scales. In this study we will analyse the way actors apply scales in their talk (or texts) to frame the complex decision-making process of the establishment

Nitrogen-doped reduced graphene oxide electrodes for electrochemical supercapacitors.

Science.gov (United States)

Nolan, Hugo; Mendoza-Sanchez, Beatriz; Ashok Kumar, Nanjundan; McEvoy, Niall; O'Brien, Sean; Nicolosi, Valeria; Duesberg, Georg S

2014-02-14

Herein we use Nitrogen-doped reduced Graphene Oxide (N-rGO) as the active material in supercapacitor electrodes. Building on a previous work detailing the synthesis of this material, electrodes were fabricated via spray-deposition of aqueous dispersions and the electrochemical charge storage mechanism was investigated. Results indicate that the functionalised graphene displays improved performance compared to non-functionalised graphene. The simplicity of fabrication suggests ease of up-scaling of such electrodes for commercial applications.

Scaling symmetry and scalar hairy Lifshitz black holes

Energy Technology Data Exchange (ETDEWEB)

Hyun, Seungjoon [Department of Physics, College of Science, Yonsei University, Seoul 120-749 (Korea, Republic of); Jeong, Jaehoon [Institute of Theoretical Physics, Aristotle University of Thessaloniki, 54124, Thessaloniki (Greece); Park, Sang-A; Yi, Sang-Heon [Department of Physics, College of Science, Yonsei University, Seoul 120-749 (Korea, Republic of)

2015-10-15

By utilizing the scaling symmetry of the reduced action for planar black holes, we obtain the corresponding conserved charge. We use the conserved charge to find the generalized Smarr relation of static hairy planar black holes in various dimensions. Our results not only reproduce the relation in the various known cases but also give the new relation in the Lifshitz planar black holes with the scalar hair.

A pragmatic approach to modelling soil and water conservation measures with a cathment scale erosion model.

NARCIS (Netherlands)

Hessel, R.; Tenge, A.J.M.

2008-01-01

To reduce soil erosion, soil and water conservation (SWC) methods are often used. However, no method exists to model beforehand how implementing such measures will affect erosion at catchment scale. A method was developed to simulate the effects of SWC measures with catchment scale erosion models.

76 FR 13526 - Reducing Regulatory Burden; Retrospective Review Under Executive Order 13563

Science.gov (United States)

2011-03-14

... participate using an existing social media account such as Facebook or Twitter. For further information, see..., and harmonize regulations to reduce costs and promote certainty for businesses and the public... your Facebook page (log-in required for IdeaScale, as well as an active Facebook and/or Twitter account...

The efficacy of local anesthetics in reducing post operative pain after appendectomy

Directory of Open Access Journals (Sweden)

Masood Baghaee vaji

2004-09-01

Full Text Available Reducing post operative pain is a common issue in surgeries. This study was to evaluate the efficacy of wound infiltration with local anesthetics in reducing postoperative pain after appendectomy. This is a double-blind, placebo-controlled, randomized clinical trial on 40 patients with non-complicated acute appendicitis. Cases received a combination of lidocaine hydrochloride and bupivacaine hydrochloride after appendectomy and before closing the wound. Controls received the same volume of saline solution. Injections were done both under the fascia of external oblique muscle and intradermal. Pain assessment was done by two pain measuring scales, VAS and NRS, in 4, 8, 12 and 24 hours after the operation. Cases and controls were the same in age, sex, and history of opium addiction. Pain peaked in the 8th hour after operation in both groups and reduced afterwards. Pain assessments showed the same pattern using the NRS and VAS measuring scales. T-test showed the pain to be significantly less in cases comparing with the controls in all time points. No significant difference was seen in the time of receiving the first analgesic after the operation but the frequency of analgesic consumption was significantly lower in controls. This study showed local anesthetic infiltration to be effective in reducing the postoperative pain in patients undergoing appendectomy which is in contrast with the previous studies. This may be due to a different infiltration technique or pain assessment in the first 24 hours after the operation.

X-ray flux and X-ray burn through experiments on reduced-scale targets at the Nif and OMEGA lasers

International Nuclear Information System (INIS)

Schneider, M.B.; Hinkel, D.E.; Young, B.K.; Holder, J.P.; Langdon, A.B.; Bower, D.E.; Bruns, H.C.; Campbell, K.M.; Celeste, J.R.; Compton, S.; Costa, R.L.; Dewald, E.L.; Dixit, S.N.; Eckart, M.J.; Eder, D.C.; Edwards, M.J.; Ellis, A.D.; Emig, J.A.; Froula, D.H.; Glebov, V.; Glenzer, S.H.; Hargrove, D.; Haynam, C.A.; Heeter, R.F.; Henesian, M.A.; Holtmeier, G.; James, D.L.; Jancaitis, K.S.; Kalantar, D.H.; Kamperschroer, J.H.; Kauffman, R.L.; Kimbrough, J.; Kirkwood, R.; Koniges, A.E.; Landen, O.L.; Landon, M.; Lee, F.D.; MacGowan, B.J.; Mackinnon, A.J.; Manes, K.R.; Marshall, C.; May, M.J.; McDonald, J.W.; Menapace, J.; Moon, S.J.; Moses, E.I.; Munro, D.H.; Murray, J.R.; Niemann, C.; Piston, K.; Power, G.D.; Rekow, V.; Ruppe, J.A.; Schein, J.; Shepherd, R.; Singh, M.S.; Sorce, C.; Springer, P.T.; Still, C.H.; Suter, L.J.; Tietbohl, G.L.; Turner, R.E.; Van Wonterghem, B.M.; Wallace, R.J.; Warrick, A.; Weber, F.; Wegner, P.J.; Williams, E.A.; Young, P.E.; Baldis, H.A.; Constantin, C.G.; Bahr, R.; Roberts, S.; Seka, W.; Stoeckl, C.; Pellinen, D.; Watts, P.

2006-01-01

An experimental campaign to maximize radiation drive in small-scale hohlraums has been carried out at the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (Livermore, USA) and at the OMEGA laser at the Laboratory for Laser Energetics (Rochester, USA). The small-scale hohlraums, laser energy, laser pulse, and diagnostics were similar at both facilities but the geometries were very different. The NIF experiments used on-axis laser beams whereas the OMEGA experiments used 19 beams in three beam cones. In the cases when the lasers coupled well and produced similar radiation drive, images of X-ray burn-through and laser deposition indicate the pattern of plasma filling is very different. The OMEGA targets fill faster than the NIF targets, which helps explain the time behavior of the X-ray fluences. (authors)

X-ray flux and X-ray burn through experiments on reduced-scale targets at the Nif and OMEGA lasers

Energy Technology Data Exchange (ETDEWEB)

Schneider, M.B.; Hinkel, D.E.; Young, B.K.; Holder, J.P.; Langdon, A.B.; Bower, D.E.; Bruns, H.C.; Campbell, K.M.; Celeste, J.R.; Compton, S.; Costa, R.L.; Dewald, E.L.; Dixit, S.N.; Eckart, M.J.; Eder, D.C.; Edwards, M.J.; Ellis, A.D.; Emig, J.A.; Froula, D.H.; Glebov, V.; Glenzer, S.H.; Hargrove, D.; Haynam, C.A.; Heeter, R.F.; Henesian, M.A.; Holtmeier, G.; James, D.L.; Jancaitis, K.S.; Kalantar, D.H.; Kamperschroer, J.H.; Kauffman, R.L.; Kimbrough, J.; Kirkwood, R.; Koniges, A.E.; Landen, O.L.; Landon, M.; Lee, F.D.; MacGowan, B.J.; Mackinnon, A.J.; Manes, K.R.; Marshall, C.; May, M.J.; McDonald, J.W.; Menapace, J.; Moon, S.J.; Moses, E.I.; Munro, D.H.; Murray, J.R.; Niemann, C.; Piston, K.; Power, G.D.; Rekow, V.; Ruppe, J.A.; Schein, J.; Shepherd, R.; Singh, M.S.; Sorce, C.; Springer, P.T.; Still, C.H.; Suter, L.J.; Tietbohl, G.L.; Turner, R.E.; Van Wonterghem, B.M.; Wallace, R.J.; Warrick, A.; Weber, F.; Wegner, P.J.; Williams, E.A.; Young, P.E. [Lawrence Livermore National Lab., Livermore, CA (United States); Baldis, H.A.; Constantin, C.G. [California at Davis Univ., CA (United States); Bahr, R.; Roberts, S.; Seka, W.; Stoeckl, C. [Laboratory for Laser Energetics, Rochester, NY (United States); Pellinen, D.; Watts, P. [Bechtel Nevada Corporation, Livermore, CA (United States)

2006-06-15

An experimental campaign to maximize radiation drive in small-scale hohlraums has been carried out at the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (Livermore, USA) and at the OMEGA laser at the Laboratory for Laser Energetics (Rochester, USA). The small-scale hohlraums, laser energy, laser pulse, and diagnostics were similar at both facilities but the geometries were very different. The NIF experiments used on-axis laser beams whereas the OMEGA experiments used 19 beams in three beam cones. In the cases when the lasers coupled well and produced similar radiation drive, images of X-ray burn-through and laser deposition indicate the pattern of plasma filling is very different. The OMEGA targets fill faster than the NIF targets, which helps explain the time behavior of the X-ray fluences. (authors)

Decadal-Scale Forecasting of Climate Drivers for Marine Applications.

Science.gov (United States)

Salinger, J; Hobday, A J; Matear, R J; O'Kane, T J; Risbey, J S; Dunstan, P; Eveson, J P; Fulton, E A; Feng, M; Plagányi, É E; Poloczanska, E S; Marshall, A G; Thompson, P A

Climate influences marine ecosystems on a range of time scales, from weather-scale (days) through to climate-scale (hundreds of years). Understanding of interannual to decadal climate variability and impacts on marine industries has received less attention. Predictability up to 10 years ahead may come from large-scale climate modes in the ocean that can persist over these time scales. In Australia the key drivers of climate variability affecting the marine environment are the Southern Annular Mode, the Indian Ocean Dipole, the El Niño/Southern Oscillation, and the Interdecadal Pacific Oscillation, each has phases that are associated with different ocean circulation patterns and regional environmental variables. The roles of these drivers are illustrated with three case studies of extreme events-a marine heatwave in Western Australia, a coral bleaching of the Great Barrier Reef, and flooding in Queensland. Statistical and dynamical approaches are described to generate forecasts of climate drivers that can subsequently be translated to useful information for marine end users making decisions at these time scales. Considerable investment is still needed to support decadal forecasting including improvement of ocean-atmosphere models, enhancement of observing systems on all scales to support initiation of forecasting models, collection of important biological data, and integration of forecasts into decision support tools. Collaboration between forecast developers and marine resource sectors-fisheries, aquaculture, tourism, biodiversity management, infrastructure-is needed to support forecast-based tactical and strategic decisions that reduce environmental risk over annual to decadal time scales. © 2016 Elsevier Ltd. All rights reserved.

VLSI scaling methods and low power CMOS buffer circuit

International Nuclear Information System (INIS)

Sharma Vijay Kumar; Pattanaik Manisha

2013-01-01

Device scaling is an important part of the very large scale integration (VLSI) design to boost up the success path of VLSI industry, which results in denser and faster integration of the devices. As technology node moves towards the very deep submicron region, leakage current and circuit reliability become the key issues. Both are increasing with the new technology generation and affecting the performance of the overall logic circuit. The VLSI designers must keep the balance in power dissipation and the circuit's performance with scaling of the devices. In this paper, different scaling methods are studied first. These scaling methods are used to identify the effects of those scaling methods on the power dissipation and propagation delay of the CMOS buffer circuit. For mitigating the power dissipation in scaled devices, we have proposed a reliable leakage reduction low power transmission gate (LPTG) approach and tested it on complementary metal oxide semiconductor (CMOS) buffer circuit. All simulation results are taken on HSPICE tool with Berkeley predictive technology model (BPTM) BSIM4 bulk CMOS files. The LPTG CMOS buffer reduces 95.16% power dissipation with 84.20% improvement in figure of merit at 32 nm technology node. Various process, voltage and temperature variations are analyzed for proving the robustness of the proposed approach. Leakage current uncertainty decreases from 0.91 to 0.43 in the CMOS buffer circuit that causes large circuit reliability. (semiconductor integrated circuits)

Scaling up: Assessing social impacts at the macro-scale

International Nuclear Information System (INIS)

Schirmer, Jacki

2011-01-01

Social impacts occur at various scales, from the micro-scale of the individual to the macro-scale of the community. Identifying the macro-scale social changes that results from an impacting event is a common goal of social impact assessment (SIA), but is challenging as multiple factors simultaneously influence social trends at any given time, and there are usually only a small number of cases available for examination. While some methods have been proposed for establishing the contribution of an impacting event to macro-scale social change, they remain relatively untested. This paper critically reviews methods recommended to assess macro-scale social impacts, and proposes and demonstrates a new approach. The 'scaling up' method involves developing a chain of logic linking change at the individual/site scale to the community scale. It enables a more problematised assessment of the likely contribution of an impacting event to macro-scale social change than previous approaches. The use of this approach in a recent study of change in dairy farming in south east Australia is described.

Custo de capital próprio em mercados emergentes: uma abordagem empírica no Brasil com o downside risk

Directory of Open Access Journals (Sweden)

Graziela Xavier Fortunato

2010-02-01

Full Text Available Este artigo visa testar empiricamente a proposta de Estrada (2000 para as empresas que compoem o Ibovespa, avaliando se para mercados emergentes existem outras medidas de risco sistematico diferentes do beta do capital asset pricing model (CAPM. Dessa forma, testou-se o downside risk que capta a parte negativa do retorno. Alem de dados em cross section, utilizaram-se dados em painel, como uma contribuição adicional ao trabalho de Estrada (2000. Os resultados encontrados não confirmam que o downside risk seja uma medida apropriada ao mercado brasileiro. Outras medidas de risco apresentaram melhor correlacao com o retorno, permitindo o calculo do custo de capital com valor diferente daquele obtido pela aplicacao do beta. De acordo com Estrada (2000, os resultados sugerem que os mercados emergentes estao em posicao intermediaria entre os mercados integrados e segmentados, tal como confirmado para o mercado brasileiro.

Exact coherent structures in an asymptotically reduced description of parallel shear flows

Science.gov (United States)

Beaume, Cédric; Knobloch, Edgar; Chini, Gregory P.; Julien, Keith

2015-02-01

A reduced description of shear flows motivated by the Reynolds number scaling of lower-branch exact coherent states in plane Couette flow (Wang J, Gibson J and Waleffe F 2007 Phys. Rev. Lett. 98 204501) is constructed. Exact time-independent nonlinear solutions of the reduced equations corresponding to both lower and upper branch states are found for a sinusoidal, body-forced shear flow. The lower branch solution is characterized by fluctuations that vary slowly along the critical layer while the upper branch solutions display a bimodal structure and are more strongly focused on the critical layer. The reduced equations provide a rational framework for investigations of subcritical spatiotemporal patterns in parallel shear flows.

Exact coherent structures in an asymptotically reduced description of parallel shear flows

International Nuclear Information System (INIS)

Beaume, Cédric; Knobloch, Edgar; Chini, Gregory P; Julien, Keith

2015-01-01

A reduced description of shear flows motivated by the Reynolds number scaling of lower-branch exact coherent states in plane Couette flow (Wang J, Gibson J and Waleffe F 2007 Phys. Rev. Lett. 98 204501) is constructed. Exact time-independent nonlinear solutions of the reduced equations corresponding to both lower and upper branch states are found for a sinusoidal, body-forced shear flow. The lower branch solution is characterized by fluctuations that vary slowly along the critical layer while the upper branch solutions display a bimodal structure and are more strongly focused on the critical layer. The reduced equations provide a rational framework for investigations of subcritical spatiotemporal patterns in parallel shear flows. (paper)

Reduced Calibration Curve for Proton Computed Tomography

International Nuclear Information System (INIS)

Yevseyeva, Olga; Assis, Joaquim de; Evseev, Ivan; Schelin, Hugo; Paschuk, Sergei; Milhoretto, Edney; Setti, Joao; Diaz, Katherin; Hormaza, Joel; Lopes, Ricardo

2010-01-01

The pCT deals with relatively thick targets like the human head or trunk. Thus, the fidelity of pCT as a tool for proton therapy planning depends on the accuracy of physical formulas used for proton interaction with thick absorbers. Although the actual overall accuracy of the proton stopping power in the Bethe-Bloch domain is about 1%, the analytical calculations and the Monte Carlo simulations with codes like TRIM/SRIM, MCNPX and GEANT4 do not agreed with each other. A tentative to validate the codes against experimental data for thick absorbers bring some difficulties: only a few data is available and the existing data sets have been acquired at different initial proton energies, and for different absorber materials. In this work we compare the results of our Monte Carlo simulations with existing experimental data in terms of reduced calibration curve, i.e. the range - energy dependence normalized on the range scale by the full projected CSDA range for given initial proton energy in a given material, taken from the NIST PSTAR database, and on the final proton energy scale - by the given initial energy of protons. This approach is almost energy and material independent. The results of our analysis are important for pCT development because the contradictions observed at arbitrary low initial proton energies could be easily scaled now to typical pCT energies.

A reduced-scaling density matrix-based method for the computation of the vibrational Hessian matrix at the self-consistent field level

International Nuclear Information System (INIS)

Kussmann, Jörg; Luenser, Arne; Beer, Matthias; Ochsenfeld, Christian

2015-01-01

An analytical method to calculate the molecular vibrational Hessian matrix at the self-consistent field level is presented. By analysis of the multipole expansions of the relevant derivatives of Coulomb-type two-electron integral contractions, we show that the effect of the perturbation on the electronic structure due to the displacement of nuclei decays at least as r −2 instead of r −1 . The perturbation is asymptotically local, and the computation of the Hessian matrix can, in principle, be performed with O(N) complexity. Our implementation exhibits linear scaling in all time-determining steps, with some rapid but quadratic-complexity steps remaining. Sample calculations illustrate linear or near-linear scaling in the construction of the complete nuclear Hessian matrix for sparse systems. For more demanding systems, scaling is still considerably sub-quadratic to quadratic, depending on the density of the underlying electronic structure

Demonstration of Hadoop-GIS: A Spatial Data Warehousing System Over MapReduce.

Science.gov (United States)

Aji, Ablimit; Sun, Xiling; Vo, Hoang; Liu, Qioaling; Lee, Rubao; Zhang, Xiaodong; Saltz, Joel; Wang, Fusheng

2013-11-01

The proliferation of GPS-enabled devices, and the rapid improvement of scientific instruments have resulted in massive amounts of spatial data in the last decade. Support of high performance spatial queries on large volumes data has become increasingly important in numerous fields, which requires a scalable and efficient spatial data warehousing solution as existing approaches exhibit scalability limitations and efficiency bottlenecks for large scale spatial applications. In this demonstration, we present Hadoop-GIS - a scalable and high performance spatial query system over MapReduce. Hadoop-GIS provides an efficient spatial query engine to process spatial queries, data and space based partitioning, and query pipelines that parallelize queries implicitly on MapReduce. Hadoop-GIS also provides an expressive, SQL-like spatial query language for workload specification. We will demonstrate how spatial queries are expressed in spatially extended SQL queries, and submitted through a command line/web interface for execution. Parallel to our system demonstration, we explain the system architecture and details on how queries are translated to MapReduce operators, optimized, and executed on Hadoop. In addition, we will showcase how the system can be used to support two representative real world use cases: large scale pathology analytical imaging, and geo-spatial data warehousing.

A randomized control study of psychological intervention to reduce anxiety, amotivation and psychological distress among medical students

Directory of Open Access Journals (Sweden)

Coumaravelou Saravanan

2014-01-01

Full Text Available Background: Test anxiety aggravates psychological distress and reduces the motivation among graduate students. This study aimed to identify psychological intervention for test anxiety, which reduces the level of psychological distress, amotivation and increases the intrinsic and extrinsic motivation among medical students. Materials and Methods: Westside test anxiety scale, Kessler Perceived Stress Scale and Academic Motivation Scale were used to measure test anxiety, psychological distress and motivation on 436 1 st year medical students. Out of 436 students, 74 students who exhibited moderate to high test anxiety were randomly divided into either experimental or waiting list group. In this true randomized experimental study, 32 participants from the intervention group received five sessions of psychological intervention consist of psychoeducation, relaxation therapy and systematic desensitization. Thirty-three students from waiting list received one session of advice and suggestions. Results: After received psychological intervention participants from the intervention group experienced less anxiety, psychological distress, and amotivation (P < 0.01 and high intrinsic and extrinsic motivation (P < 0.01 in the postassessment compared with their preassessment scores. Conclusion: Overall psychological intervention is effective to reduce anxiety scores and its related variables.

Multi-Scale Coupling Between Monte Carlo Molecular Simulation and Darcy-Scale Flow in Porous Media

KAUST Repository

Saad, Ahmed Mohamed

2016-06-01

In this work, an efficient coupling between Monte Carlo (MC) molecular simulation and Darcy-scale flow in porous media is presented. The cell centered finite difference method with non-uniform rectangular mesh were used to discretize the simulation domain and solve the governing equations. To speed up the MC simulations, we implemented a recently developed scheme that quickly generates MC Markov chains out of pre-computed ones, based on the reweighting and reconstruction algorithm. This method astonishingly reduces the required computational times by MC simulations from hours to seconds. To demonstrate the strength of the proposed coupling in terms of computational time efficiency and numerical accuracy in fluid properties, various numerical experiments covering different compressible single-phase flow scenarios were conducted. The novelty in the introduced scheme is in allowing an efficient coupling of the molecular scale and the Darcy\\'s one in reservoir simulators. This leads to an accurate description of thermodynamic behavior of the simulated reservoir fluids; consequently enhancing the confidence in the flow predictions in porous media.

Nested-scale discharge and groundwater level monitoring to improve predictions of flow route discharges and nitrate loads

NARCIS (Netherlands)

Velde, Y. van der; Rozemeijer, J.C.; Rooij, G.H.de; Geer, F.C. van; Torfs, P.J.J.F.; Louw, P.G.B. de

2010-01-01

Identifying effective measures to reduce nutrient loads of headwaters in lowland catchments requires a thorough understanding of flow routes of water and nutrients. In this paper we assess the value of nested-scale discharge and groundwater level measurements for predictions of catchment-scale

Temperature scaling method for Markov chains.

Science.gov (United States)

Crosby, Lonnie D; Windus, Theresa L

2009-01-22

The use of ab initio potentials in Monte Carlo simulations aimed at investigating the nucleation kinetics of water clusters is complicated by the computational expense of the potential energy determinations. Furthermore, the common desire to investigate the temperature dependence of kinetic properties leads to an urgent need to reduce the expense of performing simulations at many different temperatures. A method is detailed that allows a Markov chain (obtained via Monte Carlo) at one temperature to be scaled to other temperatures of interest without the need to perform additional large simulations. This Markov chain temperature-scaling (TeS) can be generally applied to simulations geared for numerous applications. This paper shows the quality of results which can be obtained by TeS and the possible quantities which may be extracted from scaled Markov chains. Results are obtained for a 1-D analytical potential for which the exact solutions are known. Also, this method is applied to water clusters consisting of between 2 and 5 monomers, using Dynamical Nucleation Theory to determine the evaporation rate constant for monomer loss. Although ab initio potentials are not utilized in this paper, the benefit of this method is made apparent by using the Dang-Chang polarizable classical potential for water to obtain statistical properties at various temperatures.

Dynamically induced Planck scale and inflation

Energy Technology Data Exchange (ETDEWEB)

Kannike, Kristjan [NICPB,Rävala 10, 10143 Tallinn (Estonia); Hütsi, Gert [Tartu Observatory,Observatooriumi 1, 61602 Tõravere (Estonia); Pizza, Liberato [Dipartimento di Fisica, Università di Pisa and INFN,Largo Bruno Pontecorvo 3, 56127 Pisa (Italy); Racioppi, Antonio [NICPB,Rävala 10, 10143 Tallinn (Estonia); Raidal, Martti [NICPB,Rävala 10, 10143 Tallinn (Estonia); Institute of Physics, University of Tartu,Ravila 14c, 50411 Tartu (Estonia); Salvio, Alberto [Departamento de Física Teórica, Universidad Autónoma de Madrid andInstituto de Física Teórica IFT-UAM/CSIC, Madrid (Spain); Strumia, Alessandro [NICPB,Rävala 10, 10143 Tallinn (Estonia); Dipartimento di Fisica, Università di Pisa and INFN,Largo Bruno Pontecorvo 3, 56127 Pisa (Italy)

2015-05-13

Theories where the Planck scale is dynamically generated from dimensionless interactions provide predictive inflationary potentials and super-Planckian field variations. We first study the minimal single field realisation in the low-energy effective field theory limit, finding the predictions n{sub s}≈0.96 for the spectral index and r≈0.13 for the tensor-to-scalar ratio, which can be reduced down to ≈0.04 in presence of large couplings. Next we consider agravity as a dimensionless quantum gravity theory finding a multifield inflation that converges towards an attractor trajectory and predicts n{sub s}≈0.96 and 0.003scale to the smallness of inflationary perturbations: both arise naturally because of small couplings, implying a reheating temperature of 10{sup 7−9} GeV. A measurement of r by KECK/BICEP3 would give us information on quantum gravity in the dimensionless scenario.

Large Scale Processes and Extreme Floods in Brazil

Science.gov (United States)

Ribeiro Lima, C. H.; AghaKouchak, A.; Lall, U.

2016-12-01

Persistent large scale anomalies in the atmospheric circulation and ocean state have been associated with heavy rainfall and extreme floods in water basins of different sizes across the world. Such studies have emerged in the last years as a new tool to improve the traditional, stationary based approach in flood frequency analysis and flood prediction. Here we seek to advance previous studies by evaluating the dominance of large scale processes (e.g. atmospheric rivers/moisture transport) over local processes (e.g. local convection) in producing floods. We consider flood-prone regions in Brazil as case studies and the role of large scale climate processes in generating extreme floods in such regions is explored by means of observed streamflow, reanalysis data and machine learning methods. The dynamics of the large scale atmospheric circulation in the days prior to the flood events are evaluated based on the vertically integrated moisture flux and its divergence field, which are interpreted in a low-dimensional space as obtained by machine learning techniques, particularly supervised kernel principal component analysis. In such reduced dimensional space, clusters are obtained in order to better understand the role of regional moisture recycling or teleconnected moisture in producing floods of a given magnitude. The convective available potential energy (CAPE) is also used as a measure of local convection activities. We investigate for individual sites the exceedance probability in which large scale atmospheric fluxes dominate the flood process. Finally, we analyze regional patterns of floods and how the scaling law of floods with drainage area responds to changes in the climate forcing mechanisms (e.g. local vs large scale).

Scale modelling in LMFBR safety

International Nuclear Information System (INIS)

Cagliostro, D.J.; Florence, A.L.; Abrahamson, G.R.

1979-01-01

This paper reviews scale modelling techniques used in studying the structural response of LMFBR vessels to HCDA loads. The geometric, material, and dynamic similarity parameters are presented and identified using the methods of dimensional analysis. Complete similarity of the structural response requires that each similarity parameter be the same in the model as in the prototype. The paper then focuses on the methods, limitations, and problems of duplicating these parameters in scale models and mentions an experimental technique for verifying the scaling. Geometric similarity requires that all linear dimensions of the prototype be reduced in proportion to the ratio of a characteristic dimension of the model to that of the prototype. The overall size of the model depends on the structural detail required, the size of instrumentation, and the costs of machining and assemblying the model. Material similarity requires that the ratio of the density, bulk modulus, and constitutive relations for the structure and fluid be the same in the model as in the prototype. A practical choice of a material for the model is one with the same density and stress-strain relationship as the operating temperature. Ni-200 and water are good simulant materials for the 304 SS vessel and the liquid sodium coolant, respectively. Scaling of the strain rate sensitivity and fracture toughness of materials is very difficult, but may not be required if these effects do not influence the structural response of the reactor components. Dynamic similarity requires that the characteristic pressure of a simulant source equal that of the prototype HCDA for geometrically similar volume changes. The energy source is calibrated in the geometry and environment in which it will be used to assure that heat transfer between high temperature loading sources and the coolant simulant and that non-equilibrium effects in two-phase sources are accounted for. For the geometry and flow conitions of interest, the

Reduced modular symmetries of threshold corrections and gauge coupling unification

Energy Technology Data Exchange (ETDEWEB)

Bailin, David; Love, Alex [Department of Physics & Astronomy, University of Sussex,Brighton, BN1 9QH (United Kingdom)

2015-04-01

We revisit the question of gauge coupling unification at the string scale in orbifold compactifications of the heterotic string for the supersymmetric Standard Model. In the presence of discrete Wilson lines threshold corrections with modular symmetry that is a subgroup of the full modular group arise. We find that reduced modular symmetries not previously reported are possible. We conjecture that the effects of such threshold corrections can be simulated using sums of terms built from Dedekind eta functions to obtain the appropriate modular symmetry. For the cases of the ℤ{sub 8}-I orbifold and the ℤ{sub 3}×ℤ{sub 6} orbifold it is easily possible to obtain gauge coupling unification at the “observed” scale with Kähler moduli T of approximately one.

Scales and scaling in turbulent ocean sciences; physics-biology coupling

Science.gov (United States)

Schmitt, Francois

2015-04-01

Geophysical fields possess huge fluctuations over many spatial and temporal scales. In the ocean, such property at smaller scales is closely linked to marine turbulence. The velocity field is varying from large scales to the Kolmogorov scale (mm) and scalar fields from large scales to the Batchelor scale, which is often much smaller. As a consequence, it is not always simple to determine at which scale a process should be considered. The scale question is hence fundamental in marine sciences, especially when dealing with physics-biology coupling. For example, marine dynamical models have typically a grid size of hundred meters or more, which is more than 105 times larger than the smallest turbulence scales (Kolmogorov scale). Such scale is fine for the dynamics of a whale (around 100 m) but for a fish larvae (1 cm) or a copepod (1 mm) a description at smaller scales is needed, due to the nonlinear nature of turbulence. The same is verified also for biogeochemical fields such as passive and actives tracers (oxygen, fluorescence, nutrients, pH, turbidity, temperature, salinity...) In this framework, we will discuss the scale problem in turbulence modeling in the ocean, and the relation of Kolmogorov's and Batchelor's scales of turbulence in the ocean, with the size of marine animals. We will also consider scaling laws for organism-particle Reynolds numbers (from whales to bacteria), and possible scaling laws for organism's accelerations.

Adjusted scaling of FDG positron emission tomography images for statistical evaluation in patients with suspected Alzheimer's disease.

Science.gov (United States)

Buchert, Ralph; Wilke, Florian; Chakrabarti, Bhismadev; Martin, Brigitte; Brenner, Winfried; Mester, Janos; Clausen, Malte

2005-10-01

Statistical parametric mapping (SPM) gained increasing acceptance for the voxel-based statistical evaluation of brain positron emission tomography (PET) with the glucose analog 2-[18F]-fluoro-2-deoxy-d-glucose (FDG) in patients with suspected Alzheimer's disease (AD). To increase the sensitivity for detection of local changes, individual differences of total brain FDG uptake are usually compensated for by proportional scaling. However, in cases of extensive hypometabolic areas, proportional scaling overestimates scaled uptake. This may cause significant underestimation of the extent of hypometabolic areas by the statistical test. To detect this problem, the authors tested for hypermetabolism. In patients with no visual evidence of true focal hypermetabolism, significant clusters of hypermetabolism in the presence of extended hypometabolism were interpreted as false-positive findings, indicating relevant overestimation of scaled uptake. In this case, scaled uptake was reduced step by step until there were no more significant clusters of hypermetabolism. In 22 consecutive patients with suspected AD, proportional scaling resulted in relevant overestimation of scaled uptake in 9 patients. Scaled uptake had to be reduced by 11.1% +/- 5.3% in these cases to eliminate the artifacts. Adjusted scaling resulted in extension of existing and appearance of new clusters of hypometabolism. Total volume of the additional voxels with significant hypometabolism depended linearly on the extent of the additional scaling and was 202 +/- 118 mL on average. Adjusted scaling helps to identify characteristic metabolic patterns in patients with suspected AD. It is expected to increase specificity of FDGPET in this group of patients.

Lightweight and Statistical Techniques for Petascale PetaScale Debugging

Energy Technology Data Exchange (ETDEWEB)

Miller, Barton

2014-06-30

This project investigated novel techniques for debugging scientific applications on petascale architectures. In particular, we developed lightweight tools that narrow the problem space when bugs are encountered. We also developed techniques that either limit the number of tasks and the code regions to which a developer must apply a traditional debugger or that apply statistical techniques to provide direct suggestions of the location and type of error. We extend previous work on the Stack Trace Analysis Tool (STAT), that has already demonstrated scalability to over one hundred thousand MPI tasks. We also extended statistical techniques developed to isolate programming errors in widely used sequential or threaded applications in the Cooperative Bug Isolation (CBI) project to large scale parallel applications. Overall, our research substantially improved productivity on petascale platforms through a tool set for debugging that complements existing commercial tools. Previously, Office Of Science application developers relied either on primitive manual debugging techniques based on printf or they use tools, such as TotalView, that do not scale beyond a few thousand processors. However, bugs often arise at scale and substantial effort and computation cycles are wasted in either reproducing the problem in a smaller run that can be analyzed with the traditional tools or in repeated runs at scale that use the primitive techniques. New techniques that work at scale and automate the process of identifying the root cause of errors were needed. These techniques significantly reduced the time spent debugging petascale applications, thus leading to a greater overall amount of time for application scientists to pursue the scientific objectives for which the systems are purchased. We developed a new paradigm for debugging at scale: techniques that reduced the debugging scenario to a scale suitable for traditional debuggers, e.g., by narrowing the search for the root-cause analysis

The use of logarithmic pulse height and energy scales in organic scintillator spectroscopy

International Nuclear Information System (INIS)

Whittlestone, S.

1980-01-01

The use of logarithmic pulse height and energy scales is advantageous for organic for organic scintillator neutron spectroscopy, providing an expanded dynamic range and economy of computer usage. An experimental logarithmic pulse height analysis system is shown to be feasible. A pulse height spectrum from a neutron measurement has been analysed using linear and logarithmic scales; the latter reduced the computer storage requirements by a factor of 13 and analysis time by 8.7, and there was no degradation of the analysed spectrum. Most of the arguments favouring use of logarithmic scales apply equally well to other types of scintillation spectroscopy. (orig.)

Large-Scale, Parallel, Multi-Sensor Atmospheric Data Fusion Using Cloud Computing

Science.gov (United States)

Wilson, B. D.; Manipon, G.; Hua, H.; Fetzer, E. J.

2013-12-01

NASA's Earth Observing System (EOS) is an ambitious facility for studying global climate change. The mandate now is to combine measurements from the instruments on the 'A-Train' platforms (AIRS, AMSR-E, MODIS, MISR, MLS, and CloudSat) and other Earth probes to enable large-scale studies of climate change over decades. Moving to multi-sensor, long-duration analyses of important climate variables presents serious challenges for large-scale data mining and fusion. For example, one might want to compare temperature and water vapor retrievals from one instrument (AIRS) to another (MODIS), and to a model (MERRA), stratify the comparisons using a classification of the 'cloud scenes' from CloudSat, and repeat the entire analysis over 10 years of data. To efficiently assemble such datasets, we are utilizing Elastic Computing in the Cloud and parallel map/reduce-based algorithms. However, these problems are Data Intensive computing so the data transfer times and storage costs (for caching) are key issues. SciReduce is a Hadoop-like parallel analysis system, programmed in parallel python, that is designed from the ground up for Earth science. SciReduce executes inside VMWare images and scales to any number of nodes in the Cloud. Unlike Hadoop, SciReduce operates on bundles of named numeric arrays, which can be passed in memory or serialized to disk in netCDF4 or HDF5. Figure 1 shows the architecture of the full computational system, with SciReduce at the core. Multi-year datasets are automatically 'sharded' by time and space across a cluster of nodes so that years of data (millions of files) can be processed in a massively parallel way. Input variables (arrays) are pulled on-demand into the Cloud using OPeNDAP URLs or other subsetting services, thereby minimizing the size of the cached input and intermediate datasets. We are using SciReduce to automate the production of multiple versions of a ten-year A-Train water vapor climatology under a NASA MEASURES grant. We will

Meta-Heuristics in Short Scale Construction: Ant Colony Optimization and Genetic Algorithm.

Science.gov (United States)

Schroeders, Ulrich; Wilhelm, Oliver; Olaru, Gabriel

2016-01-01

The advent of large-scale assessment, but also the more frequent use of longitudinal and multivariate approaches to measurement in psychological, educational, and sociological research, caused an increased demand for psychometrically sound short scales. Shortening scales economizes on valuable administration time, but might result in inadequate measures because reducing an item set could: a) change the internal structure of the measure, b) result in poorer reliability and measurement precision, c) deliver measures that cannot effectively discriminate between persons on the intended ability spectrum, and d) reduce test-criterion relations. Different approaches to abbreviate measures fare differently with respect to the above-mentioned problems. Therefore, we compare the quality and efficiency of three item selection strategies to derive short scales from an existing long version: a Stepwise COnfirmatory Factor Analytical approach (SCOFA) that maximizes factor loadings and two metaheuristics, specifically an Ant Colony Optimization (ACO) with a tailored user-defined optimization function and a Genetic Algorithm (GA) with an unspecific cost-reduction function. SCOFA compiled short versions were highly reliable, but had poor validity. In contrast, both metaheuristics outperformed SCOFA and produced efficient and psychometrically sound short versions (unidimensional, reliable, sensitive, and valid). We discuss under which circumstances ACO and GA produce equivalent results and provide recommendations for conditions in which it is advisable to use a metaheuristic with an unspecific out-of-the-box optimization function.

New methodologies for calculation of flight parameters on reduced scale wings models in wind tunnel =

Science.gov (United States)

Ben Mosbah, Abdallah

In order to improve the qualities of wind tunnel tests, and the tools used to perform aerodynamic tests on aircraft wings in the wind tunnel, new methodologies were developed and tested on rigid and flexible wings models. A flexible wing concept is consists in replacing a portion (lower and/or upper) of the skin with another flexible portion whose shape can be changed using an actuation system installed inside of the wing. The main purpose of this concept is to improve the aerodynamic performance of the aircraft, and especially to reduce the fuel consumption of the airplane. Numerical and experimental analyses were conducted to develop and test the methodologies proposed in this thesis. To control the flow inside the test sections of the Price-Paidoussis wind tunnel of LARCASE, numerical and experimental analyses were performed. Computational fluid dynamics calculations have been made in order to obtain a database used to develop a new hybrid methodology for wind tunnel calibration. This approach allows controlling the flow in the test section of the Price-Paidoussis wind tunnel. For the fast determination of aerodynamic parameters, new hybrid methodologies were proposed. These methodologies were used to control flight parameters by the calculation of the drag, lift and pitching moment coefficients and by the calculation of the pressure distribution around an airfoil. These aerodynamic coefficients were calculated from the known airflow conditions such as angles of attack, the mach and the Reynolds numbers. In order to modify the shape of the wing skin, electric actuators were installed inside the wing to get the desired shape. These deformations provide optimal profiles according to different flight conditions in order to reduce the fuel consumption. A controller based on neural networks was implemented to obtain desired displacement actuators. A metaheuristic algorithm was used in hybridization with neural networks, and support vector machine approaches and their

Monitoring of scale deposition in petroleum pipelines by means of photon scattering: a preliminary study

International Nuclear Information System (INIS)

Meric, Ilker; Johansen, Geir A.

2013-01-01

In the petroleum industry precipitation of scale onto the inner walls of hydrocarbon pipelines poses a significant challenge as, unless treated appropriately, deposits such as sulfate and carbonate scales reduce the overall flow area and even lead to blockage of entire sections of the pipework. This may in turn result in costly production suspension and maintenance work. Therefore, monitoring and characterization of scale deposits can be said to be of great importance. In this work, a preliminary feasibility study is carried out in order to investigate the possibility of utilizing photon scattering for scale detection in multiphase oil/water/gas pipelines. (author)

Linking Microbial Ecology to Geochemistry in Sulfate Reducing Systems

Science.gov (United States)

Drennan, D. M.; Lee, I.; Landkamer, L.; Almstrand, R.; Figueroa, L. A.; Sharp, J. H.

2013-12-01

Sulfate reducing bioreactors (SRBRs) can serve as passive treatment systems for mining influenced waters (MIW). An enhanced understanding of the biogeochemistry and efficacy of SRBRs can be achieved by combining molecular biological and geochemical techniques in both field and column settings. To this end, a spatial and temporal sequence of eight pilot-scale columns were analyzed employing a multidisciplinary approach using ICP-AES, next-generation sequencing, and SEM-EDX to explore the effects of variable substrate on community structure and performance (measured by Zn removal). All pilot scale reactors contained 30% limestone by mass, 7 of the 8 had variable amounts of woodchips, sawdust, and alfalfa hay, and an 8th column where the only carbon source was walnut shells. High throughput sequencing of DNA extracted from liquid in pilot-scale columns reveals, similarly to an analogous field system in Arizona, a dominance of Proteobacteria. However, after the first pore volume, performance differences between substrate permutations emerged, where columns containing exclusively walnut shells or sawdust exhibited a more effective startup and metal removal than did columns containing exclusively woodchips or alfalfa hay. SEM-EDX analysis revealed the initial formation of gypsum (CaSO4) precipitates regardless of substrate. Zn was observed in the presence of Ca, S, and O in some column samples, suggesting there was co-precipitation of Zn and CaSO4. This is congruent with micro-XAS analysis of field data suggesting iron sulfides were co-precipitating with gypsum. A SEM-EDX analysis from a subsequent sampling event (8 months into operation) indicated that precipitation may be shifting to ZnS and ZnCO3. Biplots employing Canonical Correspondence Analysis (CCA) describe how diversity scales with performance and substrate selection, and how community shifts may result in differential performance and precipitation in response to selective pressure of bioreactor material on

The Multi-Scale Model Approach to Thermohydrology at Yucca Mountain

International Nuclear Information System (INIS)

Glascoe, L; Buscheck, T A; Gansemer, J; Sun, Y

2002-01-01

The Multi-Scale Thermo-Hydrologic (MSTH) process model is a modeling abstraction of them1 hydrology (TH) of the potential Yucca Mountain repository at multiple spatial scales. The MSTH model as described herein was used for the Supplemental Science and Performance Analyses (BSC, 2001) and is documented in detail in CRWMS M and O (2000) and Glascoe et al. (2002). The model has been validated to a nested grid model in Buscheck et al. (In Review). The MSTH approach is necessary for modeling thermal hydrology at Yucca Mountain for two reasons: (1) varying levels of detail are necessary at different spatial scales to capture important TH processes and (2) a fully-coupled TH model of the repository which includes the necessary spatial detail is computationally prohibitive. The MSTH model consists of six ''submodels'' which are combined in a manner to reduce the complexity of modeling where appropriate. The coupling of these models allows for appropriate consideration of mountain-scale thermal hydrology along with the thermal hydrology of drift-scale discrete waste packages of varying heat load. Two stages are involved in the MSTH approach, first, the execution of submodels, and second, the assembly of submodels using the Multi-scale Thermohydrology Abstraction Code (MSTHAC). MSTHAC assembles the submodels in a five-step process culminating in the TH model output of discrete waste packages including a mountain-scale influence

Channel length scaling and the impact of metal gate work function ...

Indian Academy of Sciences (India)

As the channel length is reduced from one transistor generation to the next, ... As CMOS technology continues to scale, metal gate electrodes need to be intro .... in the z-direction, q is the electron charge, h is the Planck's constant, Ψ(x, z) is the.

Sub-scale Inverse Wind Turbine Blade Design Using Bound Circulation

Science.gov (United States)

Kelley, Christopher; Berg, Jonathan

2014-11-01

A goal of the National Rotor Testbed project at Sandia is to design a sub-scale wind turbine blade that has similitude to a modern, commercial size blade. However, a smaller diameter wind turbine operating at the same tip-speed-ratio exhibits a different range of operating Reynolds numbers across the blade span, thus changing the local lift and drag coefficients. Differences to load distribution also affect the wake dynamics and stability. An inverse wind turbine blade design tool has been implemented which uses a target, dimensionless circulation distribution from a full-scale blade to find the chord and twist along a sub-scale blade. In addition, airfoil polar data are interpolated from a few specified span stations leading to a smooth, manufacturable blade. The iterative process perturbs chord and twist, after running a blade element momentum theory code, to reduce the residual sum of the squares between the modeled sub-scale circulation and the target full-scale circulation. It is shown that the converged sub-scale design also leads to performance similarity in thrust and power coefficients. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy under Contract DE-AC04-94AL85000.

Scoping studies to reduce ICPP high-level radioactive waste volumes for final disposal

International Nuclear Information System (INIS)

Knecht, D.A.; Berreth, J.R.; Chipman, N.A.; Cole, H.S.; Geczi, L.S.; Kerr, W.B.; Staples, B.A.

1985-08-01

This report presents the results of scoping studies carried out to determine the feasibility of the following candidate options to reduce high-level waste volume: (1) low-fluoride, low-volume glass, (2) glass-ceramic and ceramic, (3) Modified Zirflex, (4) inerts removal by neutralization, and (5) modified Fluorinel processes. The results of the scoping studies show that the glass-ceramic/ceramic waste forms and neutralization process with potential HLW volume reductions ranging from 60 to 80% appear feasible, based on laboratory-scale tests. The presently used Fluorinel process modified by reducing HF usage also appears to be feasible and could result in up to a 10% potential volume reduction. If the current process start-up tests verify the practicality, reduced HF usage will be implemented. The low-volume glass and Modified Zirflex processes may also be feasible, based on laboratory tests, but would require significantly more process development and/or modifications and could result in only a 20 to 30% potential volume reduction. Based on these scoping studies, it is recommended that (1) the glass-ceramic/ceramic and neutralization processes be developed further, (2) reduced HF use for the Modified Fluorinel process be implemented as soon as practical and other options reducing chemical usage for criticality control be evaluated, (3) basic development for the glass process be continued as a back-up technology, and (4) laboratory-scale radioactive fuel dissolution testing for the Modified Zirflex process be completed with further process development discontinued unless needed in the future

A strategy to load balancing for non-connectivity MapReduce job

Science.gov (United States)

Zhou, Huaping; Liu, Guangzong; Gui, Haixia

2017-09-01

MapReduce has been widely used in large scale and complex datasets as a kind of distributed programming model. Original Hash partitioning function in MapReduce often results the problem of data skew when data distribution is uneven. To solve the imbalance of data partitioning, we proposes a strategy to change the remaining partitioning index when data is skewed. In Map phase, we count the amount of data which will be distributed to each reducer, then Job Tracker monitor the global partitioning information and dynamically modify the original partitioning function according to the data skew model, so the Partitioner can change the index of these partitioning which will cause data skew to the other reducer that has less load in the next partitioning process, and can eventually balance the load of each node. Finally, we experimentally compare our method with existing methods on both synthetic and real datasets, the experimental results show our strategy can solve the problem of data skew with better stability and efficiency than Hash method and Sampling method for non-connectivity MapReduce task.

Reducing discards without reducing profit: Free gear choice in a Danish result-based management trial

DEFF Research Database (Denmark)

Mortensen, Lars O.; Ulrich, Clara; Qvist Eliasen, Søren

2017-01-01

The 2013 Common Fisheries Policy introduced a landing obligation on a range of species. This is changing the fundamental principles on which EU fisheries management is based, with more focus on the full accountability of all catches (a move towards catch quota management) and less accountability...... on the means used to obtain these catches (a move towards results-based management). To investigate the potentials and challenges that these paradigm shifts give rise to, a 6-months ‘unrestricted gear’ trial was performed in Denmark in 2015,. Twelve trawlers of different size, rigging, fishing area and target......, where unwanted catches could be reduced to some extent without negative effects on economic viability. Some practical implementation challenges were nevertheless encountered, which are discussed in the perspective of implementing results-based management at full scale....

Analysis for Large Scale Integration of Electric Vehicles into Power Grids

DEFF Research Database (Denmark)

Hu, Weihao; Chen, Zhe; Wang, Xiaoru

2011-01-01

Electric Vehicles (EVs) provide a significant opportunity for reducing the consumption of fossil energies and the emission of carbon dioxide. With more and more electric vehicles integrated in the power systems, it becomes important to study the effects of EV integration on the power systems......, especially the low and middle voltage level networks. In the paper, the basic structure and characteristics of the electric vehicles are introduced. The possible impacts of large scale integration of electric vehicles on the power systems especially the advantage to the integration of the renewable energies...... are discussed. Finally, the research projects related to the large scale integration of electric vehicles into the power systems are introduced, it will provide reference for large scale integration of Electric Vehicles into power grids....

A proposal for a radiation protection scale to better communicate with the public

International Nuclear Information System (INIS)

Mueck, Konrad; Balonov, Michail; Bayer, Anton; Burkart, Klaus; Brunner, Hans H.; Drabova, Dana; Rousseau, Denys; Hu Zunsu

2000-01-01

A major problem in the communication of radiation protection experts with the public is misunderstanding of radiation protection concepts and the various units used in radiation protect which tend to confuse the public. Another problem to inability of the public to differentiate between low, medium and high doses and their possible implications. Also the public and the media are not able to comprehend the differences between units and subunits (Sv, mSv, μSv, etc.). Therefore, a simple, for the general citizen easily understandable scale for the radiation exposure of human beings is proposed which should assist in making radiation exposure values and their consequences to health more easily understandable for the general public. The logarithmic setup of the scale yields an easily understandable scale of integer numbers from 1 to 7 where the levels 0 - 3 of the scale describe the dose range of minuscule dose values below natural radiation exposure levels, level 4 the dose range of 1 - 10 mSv, i.e. the dose range of the natural radiation exposure, while level 6 and 7 define the dose range 0.1 to 1 Sv and above 1 Sv in which protective measures to reduce the dose are important or absolutely required to avoid significant effects for the concerned individuals. In the approach to facilitate the comprehension by less knowledgeable persons, the proposed radiation protection scale is comparable to other scales (INES-scale, RICHTER-scale) where events of a wide range from practically no consequences via observable effects to severe consequences are given in an understandable 'risk-scale'. In the opinion of the authors the scale would facilitate the comprehension of the public why for a given dose no action to reduce it is considered and for another dose level dose reduction measures are recommended or absolutely required. The radiation protection scale should also lead to easily understandable risk factors in an environment where radiation is considered by the public and the

Evolution of technetium speciation in reducing grout

Energy Technology Data Exchange (ETDEWEB)

Lukens, Wayne W.; Bucher, Jerome J.; Shuh, David K.; Edelstein,Norman M.

2003-11-24

Cementitious waste forms (CWFs) are an important component of the strategy to immobilize high-level nuclear waste resulting from plutonium production by the U.S. Department of Energy (DOE). Technetium (99Tc) is an abundant fission product of particular concern in CWFs due to the high solubility and mobility of pertechnetate, TcO4-, the stable form of technetium in aerobic environments. CWFs can more effectively immobilize 99Tc if they contain additives that reduce mobile TcO4- to immobile Tc(IV) species. Leaching of 99Tc from reducing CWFs that contain Tc(IV) is much slower than for CWFs containing TcO4-. Previous X-ray absorption fine structure (XAFS) studies showed that the Tc(IV) species were oxidized to TcO4- in reducing grout samples prepared on a laboratory scale. Whether the oxidizer was atmospheric O2 or NO3- in the waste simulant was not determined. In actual CWFs, rapid oxidation of Tc(IV) by NO3- would be a concern, whereas oxidation by atmospheric O2 would be of less concern due to the slow diffusion and reaction of O2 with the reducing CWF. To address this uncertainty, two series of reducing grouts were prepared using TcO4- containing waste simulants with and without NO3-. In the first series of samples, the TcO4- was completely reduced using Na2S, and the samples were placed in containers that permitted O2 diffusion. In these samples, all of the technetium was initially present as aTc(IV) sulfide compound, TcSx, which was characterized using extended X-ray absorption fine structure (EXAFS) spectroscopy, and is likely Tc2S7. The TcSx initially present in the grout samples was steadily oxidized over 4 years. In the second series of samples, all of the TcO4- was not initially reduced, and the grout samples were placed in airtight containers. In these samples, the remaining TcO4- continued to be reduced as the samples aged, presumably due to the presence of reducing blast furnace slag. When samples in the second series were exposed to atmosphere, the

Reduced dielectric response in spatially varying electric fields

DEFF Research Database (Denmark)

Hansen, Jesper Schmidt

2015-01-01

relations between the flux and the gradient of the polarization. Comparison between the theory and molecular dynamics simulations confirms this effect. The effect is significant for small length scale electric field variations and the inclusion of the flux is thus important in nanoscale modeling......In this paper, the dynamical equation for polarization is derived. From this the dielectric response to a spatially varying electric field is analyzed showing a reduced response due to flux of polarization in the material. This flux is modeled as a diffusive process through linear constitutive...

Construction and evaluation of a self rating scale for stress-induced exhaustion disorder, the Karolinska Exhaustion Disorder Scale.

Science.gov (United States)

Besèr, Aniella; Sorjonen, Kimmo; Wahlberg, Kristina; Peterson, Ulla; Nygren, Ake; Asberg, Marie

2014-02-01

Prolonged stress (≥ six months) may cause a condition which has been named exhaustion disorder (ED) with ICD-10 code F43.8. ED is characterised by exhaustion, cognitive problems, poor sleep and reduced tolerance to further stress. ED can cause long term disability and depressive symptoms may develop. The aim was to construct and evaluate a self-rating scale, the Karolinska Exhaustion Disorder Scale (KEDS), for the assessment of ED symptoms. A second aim was to examine the relationship between self-rated symptoms of ED, depression, and anxiety using KEDS and the Hospital Anxiety and Depression Scale (HAD). Items were selected based on their correspondence to criteria for ED as formulated by the Swedish National Board of Health and Welfare (NBHW), with seven response alternatives in a Likert-format. Self-ratings performed by 317 clinically assessed participants were used to analyse the scale's psychometric properties. KEDS consists of nine items with a scale range of 0-54. Receiver operating characteristics analysis demonstrated that a cut-off score of 19 was accompanied by high sensitivity and specificity (each above 95%) in the discrimination between healthy subjects and patients with ED. Reliability was satisfactory and confirmatory factor analysis revealed that ED, depression and anxiety are best regarded as different phenomena. KEDS may be a useful tool in the assessment of symptoms of Exhaustion Disorder in clinical as well as research settings. There is evidence that the symptom clusters of ED, anxiety and depression, respectively, reflect three different underlying dimensions. © 2013 The Authors. Scandinavian Journal of Psychology published by Scandinavian Psychological Associations and John Wiley & Sons Ltd.

Dynamic model-based N management reduces surplus nitrogen and improves the environmental performance of corn production

Science.gov (United States)

Sela, S.; Woodbury, P. B.; van Es, H. M.

2018-05-01

The US Midwest is the largest and most intensive corn (Zea mays, L.) production region in the world. However, N losses from corn systems cause serious environmental impacts including dead zones in coastal waters, groundwater pollution, particulate air pollution, and global warming. New approaches to reducing N losses are urgently needed. N surplus is gaining attention as such an approach for multiple cropping systems. We combined experimental data from 127 on-farm field trials conducted in seven US states during the 2011–2016 growing seasons with biochemical simulations using the PNM model to quantify the benefits of a dynamic location-adapted management approach to reduce N surplus. We found that this approach allowed large reductions in N rate (32%) and N surplus (36%) compared to existing static approaches, without reducing yield and substantially reducing yield-scaled N losses (11%). Across all sites, yield-scaled N losses increased linearly with N surplus values above ~48 kg ha‑1. Using the dynamic model-based N management approach enabled growers to get much closer to this target than using existing static methods, while maintaining yield. Therefore, this approach can substantially reduce N surplus and N pollution potential compared to static N management.

Energy transfers in large-scale and small-scale dynamos

Science.gov (United States)

Samtaney, Ravi; Kumar, Rohit; Verma, Mahendra

2015-11-01

We present the energy transfers, mainly energy fluxes and shell-to-shell energy transfers in small-scale dynamo (SSD) and large-scale dynamo (LSD) using numerical simulations of MHD turbulence for Pm = 20 (SSD) and for Pm = 0.2 on 10243 grid. For SSD, we demonstrate that the magnetic energy growth is caused by nonlocal energy transfers from the large-scale or forcing-scale velocity field to small-scale magnetic field. The peak of these energy transfers move towards lower wavenumbers as dynamo evolves, which is the reason for the growth of the magnetic fields at the large scales. The energy transfers U2U (velocity to velocity) and B2B (magnetic to magnetic) are forward and local. For LSD, we show that the magnetic energy growth takes place via energy transfers from large-scale velocity field to large-scale magnetic field. We observe forward U2U and B2B energy flux, similar to SSD.

Small-scale hydropower in the Netherlands : problems and strategies of system builders

NARCIS (Netherlands)

Manders, T.N.; Höffken, J.I.; van der Vleuten, E.B.A.

2016-01-01

Small-scale hydroelectricity (hydel) currently receives worldwide attention as a clean, green, and socially just energy technology. People generally assume that downsizing hydel plants reduces harmful impacts. However, recent debates call for careful circumspection of small hydel’s environmental,

Positron stopping in elemental systems: Monte Carlo calculations and scaling properties

International Nuclear Information System (INIS)

Ghosh, V.J.; Aers, G.C.

1995-01-01

The scaling of positron-implantation (stopping) profiles has been reported by Ghosh et al., who used the BNL Monte Carlo scheme to generate stopping profiles in semi-infinite elemental metals. A simple scaling relationship reduced the stopping profiles of positrons implanted at different energies (ranging from 1--10 keV) onto a single universal curve for that particular metal. We have confirmed that the scaling relationship also applies to the quite different Jensen and Walker Monte Carlo scheme, for more materials, and over an expanded energy range of 1--25 keV. The mean depths of the stopping profiles calculated by the two Monte Carlo schemes are found to be different, mainly due to differences in the inelastic mean free paths and the energy-loss functions. However, after scaling, the profiles generated by the two schemes can be superimposed onto a single curve which can be appropriately parametrized. The scaled profiles are found to be only weakly material dependent. The mean depths, backscattered fractions, and scaled stopping profiles are fitted to simple parametric functions, and the values of these parameters are obtained for several elements

New Estimation of the Dosage of Scale Inhibitor in the Cooling Water System

Directory of Open Access Journals (Sweden)

Jiang Jiaomei

2011-01-01

Full Text Available In the cooling water system, excessive use of organic phosphate scale inhibitors is harmful to environment. Reducing the dosage of the organic phosphate scale inhibitor is important. A self-made jacketed crystallizer was used in this experiment. The critical pH values have been determined in cooling water systems with series of Ca2+ concentrations by adding different concentration of the scale inhibitor ATMP (Amino Trimethylene Phosphonic Acid according to the calcium carbonate Metastable zone theory. A model equation at 45 °C and pH=9 was proposed to estimate the lowest dose of the scale inhibitor ATMP. The measured pH value was approximate to the expected pH value in two cooling water systems through verification test.

Corroded scale analysis from water distribution pipes

Directory of Open Access Journals (Sweden)

Rajaković-Ognjanović Vladana N.

2011-01-01

both fluid and solid, relatively dense shell-like layer that covers the porous core and provides structural integrity to the scale, and surface layer that is present on top of the shell-like layer at scale-water interface and loosely attached to the shell-like layer. Iron(II deposits are formed under reducing conditions. The presence of relatively soluble Fe(II deposits such as siderite and ferrous hydroxide was confirmed by XRD and SEM analysis. In the presence of carbonic species, siderite (FeCO3 is prevailing ferrous deposit. Further studies are needed for obtaining greater knowledge on the mechanism of iron release from corroded pipes and the influence of water quality to iron corrosion.

A multi scale model for small scale plasticity

International Nuclear Information System (INIS)

Zbib, Hussein M.

2002-01-01

Full text.A framework for investigating size-dependent small-scale plasticity phenomena and related material instabilities at various length scales ranging from the nano-microscale to the mesoscale is presented. The model is based on fundamental physical laws that govern dislocation motion and their interaction with various defects and interfaces. Particularly, a multi-scale model is developed merging two scales, the nano-microscale where plasticity is determined by explicit three-dimensional dislocation dynamics analysis providing the material length-scale, and the continuum scale where energy transport is based on basic continuum mechanics laws. The result is a hybrid simulation model coupling discrete dislocation dynamics with finite element analyses. With this hybrid approach, one can address complex size-dependent problems, including dislocation boundaries, dislocations in heterogeneous structures, dislocation interaction with interfaces and associated shape changes and lattice rotations, as well as deformation in nano-structured materials, localized deformation and shear band

Bench-Scale Silicone Process for Low-Cost CO{sub 2} Capture

Energy Technology Data Exchange (ETDEWEB)

Wood, Benjamin; Genovese, Sarah; Perry, Robert; Spiry, Irina; Farnum, Rachael; Sing, Surinder; Wilson, Paul; Buckley, Paul; Acharya, Harish; Chen, Wei; McDermott, John; Vipperia, Ravikumar; Yee, Michael; Steele, Ray; Fresia, Megan; Vogt, Kirk

2013-12-31

A bench-scale system was designed and built to test an aminosilicone-based solvent. A model was built of the bench-scale system and this model was scaled up to model the performance of a carbon capture unit, using aminosilicones, for CO{sub 2} capture and sequestration (CCS) for a pulverized coal (PC) boiler at 550 MW. System and economic analysis for the carbon capture unit demonstrates that the aminosilicone solvent has significant advantages relative to a monoethanol amine (MEA)-based system. The CCS energy penalty for MEA is 35.9% and the energy penalty for aminosilicone solvent is 30.4% using a steam temperature of 395 °C (743 °F). If the steam temperature is lowered to 204 °C (400 °F), the energy penalty for the aminosilicone solvent is reduced to 29%. The increase in cost of electricity (COE) over the non-capture case for MEA is ~109% and increase in COE for aminosilicone solvent is ~98 to 103% depending on the solvent cost at a steam temperature of 395 °C (743 °F). If the steam temperature is lowered to 204 °C (400 °F), the increase in COE for the aminosilicone solvent is reduced to ~95-100%.

Reducing high Reynolds number hydroacoustic noise using superhydrophobic coating

International Nuclear Information System (INIS)

Elboth, Thomas; Reif, Bjørn Anders Pettersson; Andreassen, Øyvind; Martell, Michael B

2011-01-01

The objective of this study is to assess and quantify the effect of a superhydrophobic surface coating on turbulence-generated flow noise. The study utilizes results obtained from high Reynolds-number full-scale flow noise measurements taken on a commercial seismic streamer and results from low Reynolds-number direct numerical simulations. It is shown that it is possible to significantly reduce both the frictional drag and the levels of the turbulence generated flow noise even at very high Reynolds-numbers. For instance, frequencies below 10 Hz a reduction in the flow noise level of nearly 50% was measured. These results can be attributed to a reduced level of shear stress and change in the kinematic structure of the turbulence, both of which occur in the immediate vicinity of the superhydrophobic surface.

Rank Dynamics of Word Usage at Multiple Scales

Directory of Open Access Journals (Sweden)

José A. Morales

2018-05-01

Full Text Available The recent dramatic increase in online data availability has allowed researchers to explore human culture with unprecedented detail, such as the growth and diversification of language. In particular, it provides statistical tools to explore whether word use is similar across languages, and if so, whether these generic features appear at different scales of language structure. Here we use the Google Books N-grams dataset to analyze the temporal evolution of word usage in several languages. We apply measures proposed recently to study rank dynamics, such as the diversity of N-grams in a given rank, the probability that an N-gram changes rank between successive time intervals, the rank entropy, and the rank complexity. Using different methods, results show that there are generic properties for different languages at different scales, such as a core of words necessary to minimally understand a language. We also propose a null model to explore the relevance of linguistic structure across multiple scales, concluding that N-gram statistics cannot be reduced to word statistics. We expect our results to be useful in improving text prediction algorithms, as well as in shedding light on the large-scale features of language use, beyond linguistic and cultural differences across human populations.

To scale or not to scale

DEFF Research Database (Denmark)

Svendsen, Morten Bo Søndergaard; Christensen, Emil Aputsiaq Flindt; Steffensen, John Fleng

2017-01-01

Conventionally, dynamic energy budget (DEB) models operate with animals that have maintenance rates scaling with their body volume, and assimilation rates scaling with body surface area. However, when applying such criteria for the individual in a population level model, the emergent behaviour...

Large-Scale Corrections to the CMB Anisotropy from Asymptotic de Sitter Mode

Science.gov (United States)

Sojasi, A.

2018-01-01

In this study, large-scale effects from asymptotic de Sitter mode on the CMB anisotropy are investigated. Besides the slow variation of the Hubble parameter onset of the last stage of inflation, the recent observational constraints from Planck and WMAP on spectral index confirm that the geometry of the universe can not be pure de Sitter in this era. Motivated by these evidences, we use this mode to calculate the power spectrum of the CMB anisotropy on the large scale. It is found that the CMB spectrum is dependent on the index of Hankel function ν which in the de Sitter limit ν → 3/2, the power spectrum reduces to the scale invariant result. Also, the result shows that the spectrum of anisotropy is dependent on angular scale and slow-roll parameter and these additional corrections are swept away by a cutoff scale parameter H ≪ M ∗ < M P .

Balancing modern Power System with large scale of wind power

DEFF Research Database (Denmark)

Basit, Abdul; Altin, Müfit; Hansen, Anca Daniela

2014-01-01

Power system operators must ensure robust, secure and reliable power system operation even with a large scale integration of wind power. Electricity generated from the intermittent wind in large propor-tion may impact on the control of power system balance and thus deviations in the power system...... frequency in small or islanded power systems or tie line power flows in interconnected power systems. Therefore, the large scale integration of wind power into the power system strongly concerns the secure and stable grid operation. To ensure the stable power system operation, the evolving power system has...... to be analysed with improved analytical tools and techniques. This paper proposes techniques for the active power balance control in future power systems with the large scale wind power integration, where power balancing model provides the hour-ahead dispatch plan with reduced planning horizon and the real time...

Challenges in scaling NLO generators to leadership computers

Science.gov (United States)

Benjamin, D.; Childers, JT; Hoeche, S.; LeCompte, T.; Uram, T.

2017-10-01

Exascale computing resources are roughly a decade away and will be capable of 100 times more computing than current supercomputers. In the last year, Energy Frontier experiments crossed a milestone of 100 million core-hours used at the Argonne Leadership Computing Facility, Oak Ridge Leadership Computing Facility, and NERSC. The Fortran-based leading-order parton generator called Alpgen was successfully scaled to millions of threads to achieve this level of usage on Mira. Sherpa and MadGraph are next-to-leading order generators used heavily by LHC experiments for simulation. Integration times for high-multiplicity or rare processes can take a week or more on standard Grid machines, even using all 16-cores. We will describe our ongoing work to scale the Sherpa generator to thousands of threads on leadership-class machines and reduce run-times to less than a day. This work allows the experiments to leverage large-scale parallel supercomputers for event generation today, freeing tens of millions of grid hours for other work, and paving the way for future applications (simulation, reconstruction) on these and future supercomputers.

Scaling of spiking and humping in keyhole welding

Energy Technology Data Exchange (ETDEWEB)

Wei, P S; Chuang, K C [Department of Mechanical and Electro-Mechanical Engineering, National Sun Yat-Sen University, Kaohsiung, Taiwan (China); DebRoy, T [Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA 16802 (United States); Ku, J S, E-mail: pswei@mail.nsysu.edu.tw, E-mail: cielo.zhuang@gmail.com, E-mail: rtd1@psu.edu, E-mail: jsku@mail.nsysu.edu.tw [Institute of Materials Science and Engineering, National Sun Yat-Sen University, Kaohsiung, Taiwan (China)

2011-06-22

Spiking, rippling and humping seriously reduce the strength of welds. The effects of beam focusing, volatile alloying element concentration and welding velocity on spiking, coarse rippling and humping in keyhole mode electron-beam welding are examined through scale analysis. Although these defects have been studied in the past, the mechanisms for their formation are not fully understood. This work relates the average amplitudes of spikes to fusion zone depth for the welding of Al 6061, SS 304 and carbon steel, and Al 5083. The scale analysis introduces welding and melting efficiencies and an appropriate power distribution to account for the focusing effects, and the energy which is reflected and escapes through the keyhole opening to the surroundings. The frequency of humping and spiking can also be predicted from the scale analysis. The analysis also reveals the interrelation between coarse rippling and humping. The data and the mechanistic findings reported in this study are useful for understanding and preventing spiking and humping during keyhole mode electron and laser beam welding.

Use of 1–4 interaction scaling factors to control the conformational equilibrium between α-helix and β-strand

International Nuclear Information System (INIS)

Pang, Yuan-Ping

2015-01-01

Highlights: • 1–4 interaction scaling factors are used to adjust conformational energy. • This article reports the effects of these factors on protein conformations. • Reducing these factors changes a helix to a strand in molecular dynamics simulation. • Increasing these factors causes the reverse conformational change. • These factors control the conformational equilibrium between helix and strand. - Abstract: 1–4 interaction scaling factors are used in AMBER forcefields to reduce the exaggeration of short-range repulsion caused by the 6–12 Lennard-Jones potential and a nonpolarizable charge model and to obtain better agreements of small-molecule conformational energies with experimental data. However, the effects of these scaling factors on protein secondary structure conformations have not been investigated until now. This article reports the finding that the 1–4 interactions among the protein backbone atoms separated by three consecutive covalent bonds are more repulsive in the α-helix conformation than in two β-strand conformations. Therefore, the 1–4 interaction scaling factors of protein backbone torsions ϕ and ψ control the conformational equilibrium between α-helix and β-strand. Molecular dynamics simulations confirm that reducing the ϕ and ψ scaling factors readily converts the α-helix conformation of AcO-(AAQAA) 3 -NH 2 to a β-strand conformation, and the reverse occurs when these scaling factors are increased. These results suggest that the ϕ and ψ scaling factors can be used to generate the α-helix or β-strand conformation in situ and to control the propensities of a forcefield for adopting secondary structure elements

Monitoring of full-scale hydrodynamic cavitation pretreatment in agricultural biogas plant.

Science.gov (United States)

Garuti, Mirco; Langone, Michela; Fabbri, Claudio; Piccinini, Sergio

2018-01-01

The implementation of hydrodynamic cavitation (HC) pretreatment for enhancing the methane potential from agricultural biomasses was evaluated in a full scale agricultural biogas plant, with molasses and corn meal as a supplementary energy source. HC batch tests were run to investigate the influence on methane production, particle size and viscosity of specific energy input. 470kJ/kgTS was chosen for the full-scale implementation. Nearly 6-months of operational data showed that the HC pretreatment maximized the specific methane production of about 10%, allowing the biogas plant to get out of the fluctuating markets of supplementary energy sources and to reduce the methane emissions. HC influenced viscosity and particle size of digestate, contributing to reduce the energy demand for mixing, heating and pumping. In the light of the obtained results the HC process appears to be an attractive and energetically promising alternative to other pretreatments for the degradation of biomasses in biogas plant. Copyright © 2017 Elsevier Ltd. All rights reserved.

A low-jitter RF PLL frequency synthesizer with high-speed mixed-signal down-scaling circuits

International Nuclear Information System (INIS)

Tang Lu; Wang Zhigong; Xue Hong; He Xiaohu; Xu Yong; Sun Ling

2010-01-01

A low-jitter RF phase locked loop (PLL) frequency synthesizer with high-speed mixed-signal down-scaling circuits is proposed. Several techniques are proposed to reduce the design complexity and improve the performance of the mixed-signal down-scaling circuit in the PLL. An improved D-latch is proposed to increase the speed and the driving capability of the DMP in the down-scaling circuit. Through integrating the D-latch with 'OR' logic for dual-modulus operation, the delays associated with both the 'OR' and D-flip-flop (DFF) operations are reduced, and the complexity of the circuit is also decreased. The programmable frequency divider of the down-scaling circuit is realized in a new method based on deep submicron CMOS technology standard cells and a more accurate wire-load model. The charge pump in the PLL is also realized with a novel architecture to improve the current matching characteristic so as to reduce the jitter of the system. The proposed RF PLL frequency synthesizer is realized with a TSMC 0.18-μm CMOS process. The measured phase noise of the PLL frequency synthesizer output at 100 kHz offset from the center frequency is only -101.52 dBc/Hz. The circuit exhibits a low RMS jitter of 3.3 ps. The power consumption of the PLL frequency synthesizer is also as low as 36 mW at a 1.8 V power supply. (semiconductor integrated circuits)

Evaluation of Kirkwood-Buff integrals via finite size scaling: a large scale molecular dynamics study

Science.gov (United States)

Dednam, W.; Botha, A. E.

2015-01-01

Solvation of bio-molecules in water is severely affected by the presence of co-solvent within the hydration shell of the solute structure. Furthermore, since solute molecules can range from small molecules, such as methane, to very large protein structures, it is imperative to understand the detailed structure-function relationship on the microscopic level. For example, it is useful know the conformational transitions that occur in protein structures. Although such an understanding can be obtained through large-scale molecular dynamic simulations, it is often the case that such simulations would require excessively large simulation times. In this context, Kirkwood-Buff theory, which connects the microscopic pair-wise molecular distributions to global thermodynamic properties, together with the recently developed technique, called finite size scaling, may provide a better method to reduce system sizes, and hence also the computational times. In this paper, we present molecular dynamics trial simulations of biologically relevant low-concentration solvents, solvated by aqueous co-solvent solutions. In particular we compare two different methods of calculating the relevant Kirkwood-Buff integrals. The first (traditional) method computes running integrals over the radial distribution functions, which must be obtained from large system-size NVT or NpT simulations. The second, newer method, employs finite size scaling to obtain the Kirkwood-Buff integrals directly by counting the particle number fluctuations in small, open sub-volumes embedded within a larger reservoir that can be well approximated by a much smaller simulation cell. In agreement with previous studies, which made a similar comparison for aqueous co-solvent solutions, without the additional solvent, we conclude that the finite size scaling method is also applicable to the present case, since it can produce computationally more efficient results which are equivalent to the more costly radial distribution

Evaluation of Kirkwood-Buff integrals via finite size scaling: a large scale molecular dynamics study

International Nuclear Information System (INIS)

Dednam, W; Botha, A E

2015-01-01

Solvation of bio-molecules in water is severely affected by the presence of co-solvent within the hydration shell of the solute structure. Furthermore, since solute molecules can range from small molecules, such as methane, to very large protein structures, it is imperative to understand the detailed structure-function relationship on the microscopic level. For example, it is useful know the conformational transitions that occur in protein structures. Although such an understanding can be obtained through large-scale molecular dynamic simulations, it is often the case that such simulations would require excessively large simulation times. In this context, Kirkwood-Buff theory, which connects the microscopic pair-wise molecular distributions to global thermodynamic properties, together with the recently developed technique, called finite size scaling, may provide a better method to reduce system sizes, and hence also the computational times. In this paper, we present molecular dynamics trial simulations of biologically relevant low-concentration solvents, solvated by aqueous co-solvent solutions. In particular we compare two different methods of calculating the relevant Kirkwood-Buff integrals. The first (traditional) method computes running integrals over the radial distribution functions, which must be obtained from large system-size NVT or NpT simulations. The second, newer method, employs finite size scaling to obtain the Kirkwood-Buff integrals directly by counting the particle number fluctuations in small, open sub-volumes embedded within a larger reservoir that can be well approximated by a much smaller simulation cell. In agreement with previous studies, which made a similar comparison for aqueous co-solvent solutions, without the additional solvent, we conclude that the finite size scaling method is also applicable to the present case, since it can produce computationally more efficient results which are equivalent to the more costly radial distribution

Bench-scale and full-scale studies of nitric oxides reduction by gaseous fuel reburning

International Nuclear Information System (INIS)

Su, S.; Xiang, J.; Sun, L.S.; Hu, S.; Zhu, J.M.

2008-01-01

Nitrogen oxides (NOx) emissions from coal-fired boilers are significant contributors to atmospheric pollution. China has specified more rigorous legal limits for NOx emissions from power plants. As a result of the need to reduce NOx emissions, cost-effective NOx reduction strategies must be explored. This paper presented detailed experimental studies on a gaseous fuel reburning process that was performed in a 36 kilowatt bench-scale down-fired furnace to define the optimal reburning operating conditions when different Chinese coals were fired in the furnace. In addition, the combustion system of a 350 megawatt full-scale boiler was retrofitted according to the experimental results. Finally, the gaseous fuel reburning was applied to the retrofitted full-scale boiler. The purpose of the study was to obtain a better understanding of the influence of the key parameters on nitric oxide (NO) reduction efficiency of the reburning process and demonstrate the gaseous fuel reburning on a 350 MWe coal-fired boiler in China. The paper described the experimental procedure with particular reference to the experimental facility and measurement; a schematic diagram of the experimental system; experimental fuels; and characteristics of coals for the reburning experiments. Results that were presented included influence of reburn zone residence time; influence of gaseous reburn fuel per cent; influence of excess air coefficient; and unburned carbon in fly ash. It was concluded that both an above 50 per cent NO reduction efficiency and low carbon loss can be obtained by the gaseous fuel reburning process under the optimal operating conditions. 20 refs., 5 tabs., 10 figs

Relevant energy scale of color confinement from lattice QCD

International Nuclear Information System (INIS)

Yamamoto, Arata; Suganuma, Hideo

2009-01-01

We propose a new lattice framework to extract the relevant gluonic energy scale of QCD phenomena which is based on a 'cut' on link variables in momentum space. This framework is expected to be broadly applicable to all lattice QCD calculations. Using this framework, we quantitatively determine the relevant energy scale of color confinement, through the analyses of the quark-antiquark potential and meson masses. The relevant energy scale of color confinement is found to be below 1.5 GeV in the Landau gauge. In fact, the string tension is almost unchanged even after cutting off the high-momentum gluon component above 1.5 GeV. When the relevant low-energy region is cut, the quark-antiquark potential is approximately reduced to a Coulomb-like potential, and each meson becomes a quasifree quark pair. As an analytical model calculation, we also investigate the dependence of the Richardson potential on the cut, and find the consistent behavior with the lattice result.

A test trial irradiation of natural rubber latex on large scale for the production of examination gloves in a production scale

International Nuclear Information System (INIS)

Devendra, R.; Kulatunge, S.; Chandralal, H.N.K.K.; Kalyani, N.M.V.; Seneviratne, J.; Wellage, S.

1996-01-01

Radiation Vulcanization of natural rubber latex has been developed extensively through various research and development programme. During these investigations many data was collected and from these data it was proved that radiation vulcanized natural rubber latex (RVNRL) can be used as a new material for industry (RVNRL symposium 1989; Makuuchi IAEA report). This material has been extensively tested in making of dipped goods and extruded products. However these investigations were confined only to laboratory experiments and these experiments mainly reflected material properties of RVNRL and only a little was observed about its behavior in actual production scale operation. The present exercise was carried out mainly to study the behavior of the material in production scale by irradiating latex on a large scale and producing gloves in a production scale plant. It was found that RVNRL can be used in conventional glove plants without making major alteration to the plant. Quality of the gloves that were produced using RVNRL is acceptable. It was also found that the small deviation of vulcanization dose will affect the crosslinking density of films. This will drastically reduce the tensile strength of the film. Crosslinking density or pre-vulcanized relax modulus (PRM) at 100% is a reliable property to control the pre vulcanization of latex by radiation

Reaching the global target to reduce stunting: an investment framework.

Science.gov (United States)

Shekar, Meera; Kakietek, Jakub; D'Alimonte, Mary R; Rogers, Hilary E; Eberwein, Julia Dayton; Akuoku, Jon Kweku; Pereira, Audrey; Soe-Lin, Shan; Hecht, Robert

2017-06-01

Childhood stunting, being short for one's age, has life-long consequences for health, human capital and economic growth. Being stunted in early childhood is associated with slower cognitive development, reduced schooling attainment and adult incomes decreased by 5-53%. The World Health Assembly has endorsed global nutrition targets including one to reduce the number of stunted children under five by 40% by 2025. The target has been included in the Sustainable Development Goals (SDG target 2.2). This paper estimates the cost of achieving this target and develops scenarios for generating the necessary financing. We focus on a key intervention package for stunting (KIPS) with strong evidence of effectiveness. Annual scale-up costs for the period of 2016-25 were estimated for a sample of 37 high burden countries and extrapolated to all low and middle income countries. The Lives Saved Tool was used to model the impact of the scale-up on stunting prevalence. We analysed data on KIPS budget allocations and expenditure by governments, donors and households to derive a global baseline financing estimate. We modelled two financing scenarios, a 'business as usual', which extends the current trends in domestic and international financing for nutrition through 2025, and another that proposes increases in financing from all sources under a set of burden-sharing rules. The 10-year financial need to scale up KIPS is US$49.5 billion. Under 'business as usual', this financial need is not met and the global stunting target is not reached. To reach the target, current financing will have to increase from US$2.6 billion to US$7.4 billion a year on average. Reaching the stunting target is feasible but will require large coordinated investments in KIPS and a supportive enabling environment. The example of HIV scale-up over 2001-11 is instructive in identifying the factors that could drive such a global response to childhood stunting. © The Author 2017. Published by Oxford University

Predicting Statistical Response and Extreme Events in Uncertainty Quantification through Reduced-Order Models

Science.gov (United States)

Qi, D.; Majda, A.

2017-12-01

A low-dimensional reduced-order statistical closure model is developed for quantifying the uncertainty in statistical sensitivity and intermittency in principal model directions with largest variability in high-dimensional turbulent system and turbulent transport models. Imperfect model sensitivity is improved through a recent mathematical strategy for calibrating model errors in a training phase, where information theory and linear statistical response theory are combined in a systematic fashion to achieve the optimal model performance. The idea in the reduced-order method is from a self-consistent mathematical framework for general systems with quadratic nonlinearity, where crucial high-order statistics are approximated by a systematic model calibration procedure. Model efficiency is improved through additional damping and noise corrections to replace the expensive energy-conserving nonlinear interactions. Model errors due to the imperfect nonlinear approximation are corrected by tuning the model parameters using linear response theory with an information metric in a training phase before prediction. A statistical energy principle is adopted to introduce a global scaling factor in characterizing the higher-order moments in a consistent way to improve model sensitivity. Stringent models of barotropic and baroclinic turbulence are used to display the feasibility of the reduced-order methods. Principal statistical responses in mean and variance can be captured by the reduced-order models with accuracy and efficiency. Besides, the reduced-order models are also used to capture crucial passive tracer field that is advected by the baroclinic turbulent flow. It is demonstrated that crucial principal statistical quantities like the tracer spectrum and fat-tails in the tracer probability density functions in the most important large scales can be captured efficiently with accuracy using the reduced-order tracer model in various dynamical regimes of the flow field with

Modification of large-scale motions in a turbulent pipe flow

Science.gov (United States)

Senshu, Kohei; Shinozaki, Hiroaki; Sakakibara, Jun

2017-11-01

We performed experiments to modify the flow structures in a fully developed turbulent flow in a straight round pipe. The modification of the flow was achieved by installing a short coaxial inner pipe. The inner pipe has ability to add continuous suction or blowing disturbance through its outer surface. The experiments were conducted at a Reynolds number of 44,000 with seven different disturbance patterns. The wall static pressure was measured and pipe friction coefficient was evaluated. The velocity distribution was measured with PIV and very large scale motions (VLSMs) were visualized. Pipe friction coefficient was increased by installing the inner pipe, while turbulence intensities over the cross section were reduced. Slight change of the friction was observed if the disturbance was added. We decomposed fluctuating velocity field in the azimuthal direction by a Fourier series expansion. As a result, we obtained that contribution of lower azimuthal mode numbers (m = 2, 3, 4) reduced while the higher modes increased. This was consistent with the observation of visualized very large scale motions.

Team sport in organisations: the Development of a scale

Directory of Open Access Journals (Sweden)

YT Joubert

2014-01-01

Full Text Available The purpose of this study was to develop an organisational team sport scale (OTSS. A series of projects was undertaken before the development of this organisational team sport scale. The initial phase, which consisted of a qualitative study, was done to get an in-depth understanding of how employees perceive organisational team sport interventions in their organisations through focus group interviews and individual interviews (n = 72 and through the literature review. In phase 2, information obtained from phase 1 was used to develop a scale which consisted of 53 items. In phase 3, a total of 209 respondents completed the scale. The number of items was reduced to 52 through principal component analyses and a five-factor structure was suggested. The final version of the OTSS contains 52 items that assess coping skills or achieve goals, relationships among participants, physical activity and health, benefits of sport for the organisation and work/life balance. Specific issues with regard to the five-factor structure are discussed and suggestions for future research are made. The findings of this study will contribute valuable new knowledge to the literature on the development of the OTSS.

Using the Positive and Negative Syndrome Scale (PANSS) to Define Different Domains of Negative Symptoms: Prediction of Everyday Functioning by Impairments in Emotional Expression and Emotional Experience.

Science.gov (United States)

Harvey, Philip D; Khan, Anzalee; Keefe, Richard S E

2017-12-01

Background: Reduced emotional experience and expression are two domains of negative symptoms. The authors assessed these two domains of negative symptoms using previously developed Positive and Negative Syndrome Scale (PANSS) factors. Using an existing dataset, the authors predicted three different elements of everyday functioning (social, vocational, and everyday activities) with these two factors, as well as with performance on measures of functional capacity. Methods: A large (n=630) sample of people with schizophrenia was used as the data source of this study. Using regression analyses, the authors predicted the three different aspects of everyday functioning, first with just the two Positive and Negative Syndrome Scale factors and then with a global negative symptom factor. Finally, we added neurocognitive performance and functional capacity as predictors. Results: The Positive and Negative Syndrome Scale reduced emotional experience factor accounted for 21 percent of the variance in everyday social functioning, while reduced emotional expression accounted for no variance. The total Positive and Negative Syndrome Scale negative symptom factor accounted for less variance (19%) than the reduced experience factor alone. The Positive and Negative Syndrome Scale expression factor accounted for, at most, one percent of the variance in any of the functional outcomes, with or without the addition of other predictors. Implications: Reduced emotional experience measured with the Positive and Negative Syndrome Scale, often referred to as "avolition and anhedonia," specifically predicted impairments in social outcomes. Further, reduced experience predicted social impairments better than emotional expression or the total Positive and Negative Syndrome Scale negative symptom factor. In this cross-sectional study, reduced emotional experience was specifically related with social outcomes, accounting for essentially no variance in work or everyday activities, and being the

One-fifth-scale and full-scale fuel element rocking tests

International Nuclear Information System (INIS)

Nau, P.V.; Olsen, B.E.

1978-06-01

Using 1 / 5 -scale and 1 / 1 -scale (prototype H451) fuel elements, one, two, or three stacked elements on a clamped base element were rocked from an initial release position. Relative displacement, rock-down loads, and dowel pin shear forces were measured. A scaled comparison between 1 / 5 -scale and 1 / 1 -scale results was made to evaluate the model scaling laws, and an error analysis was performed to assess the accuracy and usefulness of the test data

Experimental study on the influence of different thermal insulation materials on the fire dynamics in a reduced-scale enclosure

DEFF Research Database (Denmark)

Leisted, Rolff Ripke; Sørensen, Martin X.; Jomaas, Grunde

2017-01-01

Four scaled (1:5) fire experiments with two identically classified types of commercially available sandwich panels incorporating either stone wool (SW) or poly-isocyanurate (PIR) foam as cores were conducted using a modified version of the ISO 13784-1 (Reaction to fire tests for sandwich panel...

Scales

Science.gov (United States)

Scales are a visible peeling or flaking of outer skin layers. These layers are called the stratum ... Scales may be caused by dry skin, certain inflammatory skin conditions, or infections. Examples of disorders that ...

BENCH SCALE SALTSTONE PROCESS DEVELOPMENT MIXING STUDY

Energy Technology Data Exchange (ETDEWEB)

Cozzi, A.; Hansen, E.

2011-08-03

shearing was shown to reduce the rheological properties of the grout as it was processed through the transfer line. Samples taken at the static feed tank showed that gelling impacted the rheological properties of the grout before it was fed into the pump and transfer line. A comparison of the rheological properties of samples taken at the feed tank and transfer line discharge indicated shearing of the grout was occurring in the transfer line. Bench scale testing of different mixing methods with three different salt solutions showed that method of mixing influences the rheological properties of the grouts. The paddle blade mixing method of the salt solution used for the BMSR testing provided comparable rheological properties of the grout prepared in the BMSR after 14 minutes of processing, B3. The paddle blade mixing method can be used to represent BMSR results and mixing time can be adjusted to represent larger scale mixing.

Color-based scale-invariant feature detection applied in robot vision

Science.gov (United States)

Gao, Jian; Huang, Xinhan; Peng, Gang; Wang, Min; Li, Xinde

2007-11-01

The scale-invariant feature detecting methods always require a lot of computation yet sometimes still fail to meet the real-time demands in robot vision fields. To solve the problem, a quick method for detecting interest points is presented. To decrease the computation time, the detector selects as interest points those whose scale normalized Laplacian values are the local extrema in the nonholonomic pyramid scale space. The descriptor is built with several subregions, whose width is proportional to the scale factor, and the coordinates of the descriptor are rotated in relation to the interest point orientation just like the SIFT descriptor. The eigenvector is computed in the original color image and the mean values of the normalized color g and b in each subregion are chosen to be the factors of the eigenvector. Compared with the SIFT descriptor, this descriptor's dimension has been reduced evidently, which can simplify the point matching process. The performance of the method is analyzed in theory in this paper and the experimental results have certified its validity too.

[Pilot-scale purification of lipopeptide from marine-derived Bacillus marinus].

Science.gov (United States)

Gu, Kangbo; Guan, Cheng; Xu, Jiahui; Li, Shulan; Luo, Yuanchan; Shen, Guomin; Zhang, Daojing; Li, Yuanguang

2016-11-25

This research was aimed at establishing the pilot-scale purification technology of lipopeptide from marine-derived Bacillus marinus. We studied lipopeptide surfactivity interferences on scale-up unit technologies including acid precipitation, methanol extraction, solvent precipitation, salting out, extraction, silica gel column chromatography and HZ806 macroporous absorption resin column chromatography. Then, the unit technologies were combined in a certain order, to remove the impurities gradually, and to gain purified lipopeptide finally, with high recovery rate throughout the whole process. The novel pilot-scale purification technology could effectively isolate and purify lipopeptide with 87.51% to 100% purity in hectograms from 1 ton of Bacillus marinus B-9987 fermentation broth with more than 81.73% recovery rate. The first practical hectogram production of highly purified lipopeptide derived from Bacillus marinus was achieved. With this new purification method, using complex media became possible in fermentation process to reduce the fermentation cost and scale-up the purification for lipopeptide production. For practicability and economy, foaming problem resulting from massive water evaporation was avoided in this technology.

Hydro-scaling of DT implosions on the National Ignition Facility

Science.gov (United States)

Patel, Pravesh; Spears, Brian; Clark, Dan

2017-10-01

Recent implosion experiments on the National Ignition Facility (NIF) exceed 50 kJ in fusion yield and exhibit yield amplifications of >2.5-3x due to alpha-particle self-heating of the hot-spot. Two methods to increase the yield are (i) to improve the implosion quality, or stagnation pressure, at fixed target scale (by increasing implosion velocity, reducing 3D effects, etc.), and (ii) to hydrodynamically scale the capsule and absorbed energy. In the latter case the stagnation pressure remains constant, but the yield-in the absence of alpha-heating-increases as Y S 4 . 5 , where the capsule radius is increased by S, and the absorbed energy by S3 . With alpha-heating the increase with scale is considerably stronger. We present projections in the performance of current DT experiments, and the extrapolations to ignition, based on applying hydro-scaling theory and accounting for the effect of alpha-heating. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

Evaluation of treatment related fear using a newly developed fear scale for children: "Fear assessment picture scale" and its association with physiological response.

Science.gov (United States)

Tiwari, Nishidha; Tiwari, Shilpi; Thakur, Ruchi; Agrawal, Nikita; Shashikiran, N D; Singla, Shilpy

2015-01-01

Dental treatment is usually a poignant phenomenon for children. Projective scales are preferred over psychometric scales to recognize it, and to obtain the self-report from children. The aims were to evaluate treatment related fear using a newly developed fear scale for children, fear assessment picture scale (FAPS), and anxiety with colored version of modified facial affective scale (MFAS) - three faces along with physiologic responses (pulse rate and oxygen saturation) obtained by pulse oximeter before and during pulpectomy procedure. Total, 60 children of age 6-8 years who were visiting the dental hospital for the first time and needed pulpectomy treatment were selected. Children selected were of sound physical, physiological, and mental condition. Two projective scales were used; one to assess fear - FAPS and to assess anxiety - colored version of MFAS - three faces. These were co-related with the physiological responses (oxygen saturation and pulse rate) of children obtained by pulse oximeter before and during the pulpectomy procedure. Shapiro-Wilk test, McNemar's test, Wilcoxon signed ranks test, Kruskal-Wallis test, Mann-Whitney test were applied in the study. The physiological responses showed association with FAPS and MFAS though not significant. However, oxygen saturation with MFAS showed a significant change between "no anxiety" and "some anxiety" as quantified by Kruskal-Wallis test value 6.287, P = 0.043 (test is easy and fast to apply on children and reduces the chair-side time.

Semantic similarity between ontologies at different scales

Energy Technology Data Exchange (ETDEWEB)

Zhang, Qingpeng; Haglin, David J.

2016-04-01

In the past decade, existing and new knowledge and datasets has been encoded in different ontologies for semantic web and biomedical research. The size of ontologies is often very large in terms of number of concepts and relationships, which makes the analysis of ontologies and the represented knowledge graph computational and time consuming. As the ontologies of various semantic web and biomedical applications usually show explicit hierarchical structures, it is interesting to explore the trade-offs between ontological scales and preservation/precision of results when we analyze ontologies. This paper presents the first effort of examining the capability of this idea via studying the relationship between scaling biomedical ontologies at different levels and the semantic similarity values. We evaluate the semantic similarity between three Gene Ontology slims (Plant, Yeast, and Candida, among which the latter two belong to the same kingdom—Fungi) using four popular measures commonly applied to biomedical ontologies (Resnik, Lin, Jiang-Conrath, and SimRel). The results of this study demonstrate that with proper selection of scaling levels and similarity measures, we can significantly reduce the size of ontologies without losing substantial detail. In particular, the performance of Jiang-Conrath and Lin are more reliable and stable than that of the other two in this experiment, as proven by (a) consistently showing that Yeast and Candida are more similar (as compared to Plant) at different scales, and (b) small deviations of the similarity values after excluding a majority of nodes from several lower scales. This study provides a deeper understanding of the application of semantic similarity to biomedical ontologies, and shed light on how to choose appropriate semantic similarity measures for biomedical engineering.

Large scale land acquisitions and REDD+: a synthesis of conflicts and opportunities

NARCIS (Netherlands)

Carter, Sarah; Manceur, Ameur M.; Seppelt, Ralf; Hermans, Kathleen; Herold, Martin; Verchot, Louis V.

2017-01-01

Large scale land acquisitions (LSLA), and Reducing Emissions from Deforestation and forest Degradation (REDD+) are both land based phenomena which when occurring in the same area, can compete with each other for land. A quantitative analysis of country characteristics revealed that land available

Active fans and grizzly bears: Reducing risks for wilderness campers

Science.gov (United States)

Sakals, M. E.; Wilford, D. J.; Wellwood, D. W.; MacDougall, S. A.

2010-03-01

Active geomorphic fans experience debris flows, debris floods and/or floods (hydrogeomorphic processes) that can be hazards to humans. Grizzly bears ( Ursus arctos) can also be a hazard to humans. This paper presents the results of a cross-disciplinary study that analyzed both hydrogeomorphic and grizzly bear hazards to wilderness campers on geomorphic fans along a popular hiking trail in Kluane National Park and Reserve in southwestern Yukon Territory, Canada. Based on the results, a method is proposed to reduce the risks to campers associated with camping on fans. The method includes both landscape and site scales and is based on easily understood and readily available information regarding weather, vegetation, stream bank conditions, and bear ecology and behaviour. Educating wilderness campers and providing a method of decision-making to reduce risk supports Parks Canada's public safety program; a program based on the principle of user self-sufficiency. Reducing grizzly bear-human conflicts complements the efforts of Parks Canada to ensure a healthy grizzly bear population.

Communication: An effective linear-scaling atomic-orbital reformulation of the random-phase approximation using a contracted double-Laplace transformation