Use of X-ray CT-defined regions of interest for the determination of SPECT recovery coefficients

International Nuclear Information System (INIS)

Tang, H.R.; Brown, J.K.; Hasegawa, B.H.

1996-01-01

For accurate activity per unit volume measurements in SPECT, recovery coefficients are usually applied based on the size and shape of objects being imaged to properly account for the resolution limitations of the gamma camera. Because of noise and limited spatial resolution, determination of object sizes and boundaries can be difficult using the SPECT images alone. We therefore have developed a technique which determines activity concentrations for SPECT using regions of interest (ROI's) obtained from coregistered X-ray CT images. In this study, experimental phantoms containing cylindrical and spherical objects were imaged on a combined X-ray CT/SPECT system and reconstructed data volumes were registered using the known geometry of the system. ROI's were defined on the registered CT images and used to help quantify activity concentration in localized regions and to measure object volumes. We have derived the recovery curves for these objects and scan technique. We have also tested a technique that demonstrates activity quantitation without the need for object and size dependent recovery coefficients in the case of low background

Marine Geoid Undulation Assessment Over South China Sea Using Global Geopotential Models and Airborne Gravity Data

Science.gov (United States)

Yazid, N. M.; Din, A. H. M.; Omar, K. M.; Som, Z. A. M.; Omar, A. H.; Yahaya, N. A. Z.; Tugi, A.

2016-09-01

Global geopotential models (GGMs) are vital in computing global geoid undulations heights. Based on the ellipsoidal height by Global Navigation Satellite System (GNSS) observations, the accurate orthometric height can be calculated by adding precise and accurate geoid undulations model information. However, GGMs also provide data from the satellite gravity missions such as GRACE, GOCE and CHAMP. Thus, this will assist to enhance the global geoid undulations data. A statistical assessment has been made between geoid undulations derived from 4 GGMs and the airborne gravity data provided by Department of Survey and Mapping Malaysia (DSMM). The goal of this study is the selection of the best possible GGM that best matches statistically with the geoid undulations of airborne gravity data under the Marine Geodetic Infrastructures in Malaysian Waters (MAGIC) Project over marine areas in Sabah. The correlation coefficients and the RMS value for the geoid undulations of GGM and airborne gravity data were computed. The correlation coefficients between EGM 2008 and airborne gravity data is 1 while RMS value is 0.1499.In this study, the RMS value of EGM 2008 is the lowest among the others. Regarding to the statistical analysis, it clearly represents that EGM 2008 is the best fit for marine geoid undulations throughout South China Sea.

Recovery coefficients for the quantification of the arterial input function from dynamic pet measurements: experimental and theoretical determination

International Nuclear Information System (INIS)

Brix, G.; Bellemann, M.E.; Hauser, H.; Doll, J.

2002-01-01

Aim: For kinetic modelling of dynamic PET data, the arterial input function can be determined directly from the PET scans if a large artery is visualized on the images. It was the purpose of this study to experimentally and theoretically determine recovery coefficients for cylinders as a function of the diameter and level of background activity. Methods: The measurements were performed using a phantom with seven cylinder inserts (φ = 5-46 mm). The cylinders were filled with an aqueous 68 Ga solution while the main chamber was filled with a 18 F solution in order to obtain a varying concentration ratio between the cylinders and the background due to the different isotope half lives. After iterative image reconstruction, the activity concentrations were measured in the center of the cylinders and the recovery coefficients were calculated as a function of the diameter and the background activity. Based on the imaging properties of the PET system, we also developed a model for the quantitative assessment of recovery coefficients. Results: The functional dependence of the measured recovery data from the cylinder diameter and the concentration ratio is well described by our model. For dynamic PET measurements, the recovery correction must take into account the decreasing concentration ratio between the blood vessel and the surrounding tissue. Under the realized measurement and data analysis conditions, a recovery correction is required for vessels with a diameter of up to 25 mm. Conclusions: Based on the experimentally verified model, the activity concentration in large arteries can be calculated from the measured activity concentration in the blood vessel and the background activity. The presented approach offers the possibility to determine the arterial input function for pharmacokinetic PET studies non-invasively from large arteries (especially the aorta). (orig.) [de

Iodine-124 PET dosimetry in differentiated thyroid cancer: recovery coefficient in 2D and 3D modes for PET(/CT) systems

Energy Technology Data Exchange (ETDEWEB)

Jentzen, Walter; Freudenberg, Lutz; Brandau, Wolfgang; Bockisch, Andreas [Universitaet Duisburg-Essen, Klinik fuer Nuklearmedizin, Essen (Germany); Weise, Reiner; Burchert, Wolfgang [Institut fuer Radiologie, Nuklearmedizin und Molekulare Bildgebung, Herz- und Diabeteszentrum NRW, Bad Oeynhausen (Germany); Kupferschlaeger, Juergen; Bares, Ronald [Universitaet Tuebingen, Klinik fuer Nuklearmedizin, Tuebingen (Germany)

2008-03-15

This study evaluated the absolute quantification of iodine-124 ({sup 124}I) activity concentration with respect to the use of this isotope for dosimetry before therapies with {sup 131}I or {sup 131}I-labeled radiotherapeuticals. The recovery coefficients of positron emission tomography(/computed tomography) PET(/CT) systems using {sup 124}I were determined using phantoms and then validated under typical conditions observed in differentiated thyroid cancer (DTC) patients. Transversal spatial resolution and recovery measurements with {sup 124}I and with fluorine-18 ({sup 18}F) as the reference were performed using isotope-containing line sources embedded in water and six isotope-containing spheres 9.7 to 37.0 mm in diameter placed in water-containing body and cylinder phantoms. The cylinder phantom spheres were filled with {sup 18}F only. Measurements in two-dimensional (2D) and three-dimensional (3D) modes were performed using both stand-alone PET (EXACT HR{sup +}) and combined PET/CT (BIOGRAPH EMOTION DUO) systems. Recovery comparison measurements were additionally performed on a GE ADVANCE PET system using the cylinder phantom. The recovery coefficients were directly determined using the activity concentration of circular regions of interest divided by the prepared activity concentration determined by the dose calibrator. The recovery correction method was validated using three consecutive scans of the body phantom under our {sup 124}I PET(/CT) protocol for DTC patients. Compared with that of {sup 18}F, transversal spatial resolution of {sup 124}I was slightly, but statistically significantly degraded (7.4 mm vs. 8.3 mm, P<0.002). Using the body phantom, recovery was lower for {sup 124}I than for {sup 18}F in both 2D and 3D modes. The {sup 124}I recovery coefficient of the largest sphere was significantly higher in 2D than in 3D mode (81% vs. 75%, P=0.03). Remarkably, the {sup 18}F recovery coefficient for the largest sphere significantly deviated from unity

Modeling and estimation of a low degree geopotential model from terrestrial gravity data

Science.gov (United States)

Pavlis, Nikolaos K.

1988-01-01

The development of appropriate modeling and adjustment procedures for the estimation of harmonic coefficients of the geopotential, from surface gravity data was studied, in order to provide an optimum way of utilizing the terrestrial gravity information in combination solutions currently developed at NASA/Goddard Space Flight Center, for use in the TOPEX/POSEIDON mission. The mathematical modeling was based on the fundamental boundary condition of the linearized Molodensky boundary value problem. Atmospheric and ellipsoidal corrections were applied to the surface anomalies. Terrestrial gravity solutions were found to be in good agreement with the satellite ones over areas which are well surveyed (gravimetrically), such as North America or Australia. However, systematic differences between the terrestrial only models and GEMT1, over extended regions in Africa, the Soviet Union, and China were found. In Africa, gravity anomaly differences on the order of 20 mgals and undulation differences on the order of 15 meters, over regions extending 2000 km in diameter, occur. Comparisons of the GEMT1 implied undulations with 32 well distributed Doppler derived undulations gave an RMS difference of 2.6 m, while corresponding comparison with undulations implied by the terrestrial solution gave RMS difference on the order of 15 m, which implies that the terrestrial data in that region are substantially in error.

Clustering of France Monthly Precipitation, Temperature and Discharge Based on their Multiresolution Links with 500mb Geopotential Height from 1968 to 2008

Science.gov (United States)

Massei, N.; Fossa, M.; Dieppois, B.; Vidal, J. P.; Fournier, M.; Laignel, B.

2017-12-01

In the context of climate change and ever growing use of water resources, identifying how the climate and watershed signature in discharge variability changes with the geographic location is of prime importance. This study aims at establishing how 1968-2008 multiresolution links between 3 local hydrometerological variables (precipitation, temperature and discharge) and 500 mb geopotential height are structured over France. First, a methodology that allows to encode the 3D geopotential height data into its 1D conformal modulus time series is introduced. Then, for each local variable, their covariations with the geopotential height are computed with cross wavelet analysis. Finally, a clustering analysis of each variable cross spectra is done using bootstrap clustering.We compare the clustering results for each local variable in order to untangle the watershed from the climate drivers in France's rivers discharge. Additionally, we identify the areas in the geopotential height field that are responsible for the spatial structure of each local variable.Main results from this study show that for precipitation and discharge, clear spatial zones emerge. Each cluster is characterized either by different different amplitudes and/or time scales of covariations with geopotential height. Precipitation and discharge clustering differ with the later being simpler which indicates a strong low frequency modulation by the watersheds all over France. Temperature on the other hand shows less clearer spatial zones. For precipitation and discharge, we show that the main action path starts at the northern tropical zone then moves up the to central North Atlantic zone which seems to indicates an interaction between the convective cells variability and the reinforcement of the westerlies jets as one of the main control of the precipitation and discharge over France. Temperature shows a main zone of action directly over France hinting at local temperature/pressure interactions.

Testing global geopotential models through comparison of a local quasi-geoid model with GPS/leveling data

Czech Academy of Sciences Publication Activity Database

Novák, P.; Kostelecký, J.; Klokočník, Jaroslav

2009-01-01

Roč. 53, č. 1 (2009), s. 39-60 ISSN 0039-3169 R&D Projects: GA AV ČR IAA3003407; GA MŠk(CZ) LC506 Institutional research plan: CEZ:AV0Z10030501 Keywords : global geopotential model s * CHAMP * GRACE Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 1.000, year: 2009

Iodine-124 PET dosimetry in differentiated thyroid cancer: recovery coefficient in 2D and 3D modes for PET(/CT) systems.

Science.gov (United States)

Jentzen, Walter; Weise, Reiner; Kupferschläger, Jürgen; Freudenberg, Lutz; Brandau, Wolfgang; Bares, Ronald; Burchert, Wolfgang; Bockisch, Andreas

2008-03-01

This study evaluated the absolute quantification of iodine-124 ((124)I) activity concentration with respect to the use of this isotope for dosimetry before therapies with (131)I or (131)I-labeled radiotherapeuticals. The recovery coefficients of positron emission tomography(/computed tomography) PET(/CT) systems using (124)I were determined using phantoms and then validated under typical conditions observed in differentiated thyroid cancer (DTC) patients. Transversal spatial resolution and recovery measurements with (124)I and with fluorine-18 ((18)F) as the reference were performed using isotope-containing line sources embedded in water and six isotope-containing spheres 9.7 to 37.0 mm in diameter placed in water-containing body and cylinder phantoms. The cylinder phantom spheres were filled with (18)F only. Measurements in two-dimensional (2D) and three-dimensional (3D) modes were performed using both stand-alone PET (EXACT HR(+)) and combined PET/CT (BIOGRAPH EMOTION DUO) systems. Recovery comparison measurements were additionally performed on a GE ADVANCE PET system using the cylinder phantom. The recovery coefficients were directly determined using the activity concentration of circular regions of interest divided by the prepared activity concentration determined by the dose calibrator. The recovery correction method was validated using three consecutive scans of the body phantom under our (124)I PET(/CT) protocol for DTC patients. Compared with that of (18)F, transversal spatial resolution of (124)I was slightly, but statistically significantly degraded (7.4 mm vs. 8.3 mm, P or =12.6 mm in diameter. Recovery correction is mandatory for (124)I PET quantification, even for large structures. To ensure accurate dosimetry, thorough absolute recovery measurements must be individually established for the particular PET scanner and radionuclide to be used.

An assessment of gravity model improvements using TOPEX/Poseidon TDRSS observations

Science.gov (United States)

Putney, B. H.; Teles, J.; Eddy, W. F.; Klosko, S. M.

1992-01-01

The contribution of TOPEX/Poseidon (T/P) TDRSS data to geopotential model recovery is assessed. Simulated TDRSS one-way and Bilateration Ranging Transponder System (BRTS) observations have been generated and orbitally reduced to form normal equations for geopotential parameters. These normals have been combined with those of the latest prelaunch T/P gravity model solution using data from over 30 satellites. A study of the resulting solution error covariance shows that TDRSS can make important contributions to geopotential recovery, especially for improving T/P specific effects like those arising from orbital resonance. It is argued that future effort is desirable both to establish TDRSS orbit determination limits in a reference frame compatible with that used for the precise laser/DORIS orbits, and the reduction of these TDRSS data for geopotential recovery.

The geopotential value W 0 for specifying the relativistic atomic time scale and a global vertical reference system

Czech Academy of Sciences Publication Activity Database

Burša, Milan; Kenyon, S.; Kouba, J.; Šíma, Zdislav; Vatrt, V.; Vítek, V.; Vojtíšková, M.

2007-01-01

Roč. 81, č. 2 (2007), s. 103-110 ISSN 0949-7714 R&D Projects: GA ČR GA205/05/2381 Institutional research plan: CEZ:AV0Z10030501 Keywords : geopotential * vertical datum unification * relativistic atomic time scale Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 1.636, year: 2007

Validation of gravity data from the geopotential field model for subsurface investigation of the Cameroon Volcanic Line (Western Africa)

Science.gov (United States)

Marcel, Jean; Abate Essi, Jean Marcel; Nouck, Philippe Njandjock; Sanda, Oumarou; Manguelle-Dicoum, Eliézer

2018-03-01

Belonging to the Cameroon Volcanic Line (CVL), the western part of Cameroon is an active volcanic zone with volcanic eruptions and deadly gas emissions. The volcanic flows generally cover areas and bury structural features like faults. Terrestrial gravity surveys can hardly cover entirely this mountainous area due to difficult accessibility. The present work aims to evaluate gravity data derived from the geopotential field model, EGM2008 to investigate the subsurface of the CVL. The methodology involves upward continuation, horizontal gradient, maxima of horizontal gradient-upward continuation combination and Euler deconvolution techniques. The lineaments map inferred from this geopotential field model confirms several known lineaments and reveals new ones covered by lava flows. The known lineaments are interpreted as faults or geological contacts such as the Foumban fault and the Pan-African Belt-Congo craton contact. The lineaments highlighted coupled with the numerous maar lakes identified in this volcanic sector attest of the vulnerability of the CVL where special attention should be given for geohazard prevention.

LIMS/Nimbus-7 Level 2 Vertical Profiles of O3, NO2, H2O, HNO3, Geopotential Height, and Temperature V006

Data.gov (United States)

National Aeronautics and Space Administration — The Limb Infrared Monitor of the Stratosphere (LIMS) version 6 Level-2 data product consists of daily, geolocated, vertical profiles of temperature, geopotential...

Effects of air-sea interaction on extended-range prediction of geopotential height at 500 hPa over the northern extratropical region

Science.gov (United States)

Wang, Xujia; Zheng, Zhihai; Feng, Guolin

2018-04-01

The contribution of air-sea interaction on the extended-range prediction of geopotential height at 500 hPa in the northern extratropical region has been analyzed with a coupled model form Beijing Climate Center and its atmospheric components. Under the assumption of the perfect model, the extended-range prediction skill was evaluated by anomaly correlation coefficient (ACC), root mean square error (RMSE), and signal-to-noise ratio (SNR). The coupled model has a better prediction skill than its atmospheric model, especially, the air-sea interaction in July made a greater contribution for the improvement of prediction skill than other months. The prediction skill of the extratropical region in the coupled model reaches 16-18 days in all months, while the atmospheric model reaches 10-11 days in January, April, and July and only 7-8 days in October, indicating that the air-sea interaction can extend the prediction skill of the atmospheric model by about 1 week. The errors of both the coupled model and the atmospheric model reach saturation in about 20 days, suggesting that the predictable range is less than 3 weeks.

Application of neural network technique to determine a corrector surface for global geopotential model using GPS/levelling measurements in Egypt

Science.gov (United States)

Elshambaky, Hossam Talaat

2018-01-01

Owing to the appearance of many global geopotential models, it is necessary to determine the most appropriate model for use in Egyptian territory. In this study, we aim to investigate three global models, namely EGM2008, EIGEN-6c4, and GECO. We use five mathematical transformation techniques, i.e., polynomial expression, exponential regression, least-squares collocation, multilayer feed forward neural network, and radial basis neural networks to make the conversion from regional geometrical geoid to global geoid models and vice versa. From a statistical comparison study based on quality indexes between previous transformation techniques, we confirm that the multilayer feed forward neural network with two neurons is the most accurate of the examined transformation technique, and based on the mean tide condition, EGM2008 represents the most suitable global geopotential model for use in Egyptian territory to date. The final product gained from this study was the corrector surface that was used to facilitate the transformation process between regional geometrical geoid model and the global geoid model.

The Geopotential Research Mission - Mapping the near earth gravity and magnetic fields

Science.gov (United States)

Taylor, P. T.; Keating, T.; Smith, D. E.; Langel, R. A.; Schnetzler, C. C.; Kahn, W. D.

1983-01-01

The Geopotential Research Mission (GRM), NASA's low-level satellite system designed to measure the gravity and magnetic fields of the earth, and its objectives are described. The GRM will consist of two, Shuttle launched, satellite systems (300 km apart) that will operate simultaneously at a 160 km circular-polar orbit for six months. Current mission goals include mapping the global geoid to 10 cm, measuring gravity-field anomalies to 2 mgal with a spatial resolution of 100 km, detecting crustal magnetic anomalies of 100 km wavelength with 1 nT accuracy, measuring the vectors components to + or - 5 arc sec and 5 nT, and computing the main dipole or core field to 5 nT with a 2 nT/year secular variation detection. Resource analysis and exploration geology are additional applications considered.

Using eddy geopotential height to measure the western North Pacific subtropical high in a warming climate

Science.gov (United States)

He, Chao; Lin, Ailan; Gu, Dejun; Li, Chunhui; Zheng, Bin; Wu, Bo; Zhou, Tianjun

2018-01-01

The western North Pacific subtropical high (WNPSH) is crucial to the East Asian summer climate, and geopotential height ( H) is widely used to measure the WPNSH. However, a rapidly rising trend of H in the future is projected by the models from the Coupled Model Intercomparison Project Phase 5 (CMIP5). Diagnoses based on the hypsometric equation suggest that more than 80% of the rise in H are attributable to zonal uniform warming. Because circulation is determined by the gradient of H rather than its absolute magnitude, the spatially uniform rising trend of H gives rise to difficulties when measuring the WNPSH with H. These difficulties include an invalid western boundary of WNPSH in the future and spurious information regarding long-term trends and interannual variability of WNPSH. Using CMIP5 model simulations and reanalysis data, the applicability of a metric based on eddy geopotential height ( H e ) to the warming climate is investigated. The results show that the H e metric outperforms the H metric under warming climate conditions. First, the mean state rainfall- H e relationship is more robust than the rainfall- H relationship. Second, the area, intensity, and western boundary indices of WNPSH can be effectively defined by the H e = 0-m contour in future warming climate scenarios without spurious trends. Third, the interannual variability of East Asian summer rainfall is more closely related to the H e -based WNPSH indices. We recommend that the H e metric be adopted as an operational metric on the WNPSH under the current warming climate.

The use of absolute gravity data for the validation of Global Geopotential Models and for improving quasigeoid heights determined from satellite-only Global Geopotential Models

Science.gov (United States)

Godah, Walyeldeen; Krynski, Jan; Szelachowska, Malgorzata

2018-05-01

The objective of this paper is to demonstrate the usefulness of absolute gravity data for the validation of Global Geopotential Models (GGMs). It is also aimed at improving quasigeoid heights determined from satellite-only GGMs using absolute gravity data. The area of Poland, as a unique one, covered with a homogeneously distributed set of absolute gravity data, has been selected as a study area. The gravity anomalies obtained from GGMs were validated using the corresponding ones determined from absolute gravity data. The spectral enhancement method was implemented to overcome the spectral inconsistency in data being validated. The quasigeoid heights obtained from the satellite-only GGM as well as from the satellite-only GGM in combination with absolute gravity data were evaluated with high accuracy GNSS/levelling data. Estimated accuracy of gravity anomalies obtained from GGMs investigated is of 1.7 mGal. Considering omitted gravity signal, e.g. from degree and order 101 to 2190, satellite-only GGMs can be validated at the accuracy level of 1 mGal using absolute gravity data. An improvement up to 59% in the accuracy of quasigeoid heights obtained from the satellite-only GGM can be observed when combining the satellite-only GGM with absolute gravity data.

Improvement of semi-quantitative small-animal PET data with recovery coefficients: a phantom and rat study.

Science.gov (United States)

Aide, Nicolas; Louis, Marie-Hélène; Dutoit, Soizic; Labiche, Alexandre; Lemoisson, Edwige; Briand, Mélanie; Nataf, Valérie; Poulain, Laurent; Gauduchon, Pascal; Talbot, Jean-Noël; Montravers, Françoise

2007-10-01

To evaluate the accuracy of semi-quantitative small-animal PET data, uncorrected for attenuation, and then of the same semi-quantitative data corrected by means of recovery coefficients (RCs) based on phantom studies. A phantom containing six fillable spheres (diameter range: 4.4-14 mm) was filled with an 18F-FDG solution (spheres/background activity=10.1, 5.1 and 2.5). RCs, defined as measured activity/expected activity, were calculated. Nude rats harbouring tumours (n=50) were imaged after injection of 18F-FDG and sacrificed. The standardized uptake value (SUV) in tumours was determined with small-animal PET and compared to ex-vivo counting (ex-vivo SUV). Small-animal PET SUVs were corrected with RCs based on the greatest tumour diameter. Tumour proliferation was assessed with cyclin A immunostaining and correlated to the SUV. RCs ranged from 0.33 for the smallest sphere to 0.72 for the largest. A sigmoidal correlation was found between RCs and sphere diameters (r(2)=0.99). Small-animal PET SUVs were well correlated with ex-vivo SUVs (y=0.48x-0.2; r(2)=0.71) and the use of RCs based on the greatest tumour diameter significantly improved regression (y=0.84x-0.81; r(2)=0.77), except for tumours with important necrosis. Similar results were obtained without sacrificing animals, by using PET images to estimate tumour dimensions. RC-based corrections improved correlation between small-animal PET SUVs and tumour proliferation (uncorrected data: Rho=0.79; corrected data: Rho=0.83). Recovery correction significantly improves both accuracy of small-animal PET semi-quantitative data in rat studies and their correlation with tumour proliferation, except for largely necrotic tumours.

Stochastic Orbit Prediction Using KAM Tori

Science.gov (United States)

2011-03-24

8 1.5 Problem Statement and Approach ...Semiminor axis ⃑⃑ Laplace vector ⃑ Fourier series real coefficient vector Dimensionless geopotential coefficient Geocentric ...Time of periapsis passage Observation partial derivative matrix Argument of latitude Geocentric longitude State transition matrix

Thermometric convection coefficients for rocket meteorological sensors (tables)

Science.gov (United States)

Staffanson, F. L.

1974-01-01

Values of the convective heat transfer coefficient h, and the recovery factor r, for miniature beads, fine wires, and films in rarefied air flow are shown. Data provide a standard reference for computing consistent operational corrections to rocket meteorological measurements, and for predicting the performance of existing and proposed sensor systems.

Characterizing and modeling the free recovery and constrained recovery behavior of a polyurethane shape memory polymer

International Nuclear Information System (INIS)

Volk, Brent L; Lagoudas, Dimitris C; Maitland, Duncan J

2011-01-01

In this work, tensile tests and one-dimensional constitutive modeling were performed on a high recovery force polyurethane shape memory polymer that is being considered for biomedical applications. The tensile tests investigated the free recovery (zero load) response as well as the constrained displacement recovery (stress recovery) response at extension values up to 25%, and two consecutive cycles were performed during each test. The material was observed to recover 100% of the applied deformation when heated at zero load in the second thermomechanical cycle, and a stress recovery of 1.5–4.2 MPa was observed for the constrained displacement recovery experiments. After the experiments were performed, the Chen and Lagoudas model was used to simulate and predict the experimental results. The material properties used in the constitutive model—namely the coefficients of thermal expansion, shear moduli, and frozen volume fraction—were calibrated from a single 10% extension free recovery experiment. The model was then used to predict the material response for the remaining free recovery and constrained displacement recovery experiments. The model predictions match well with the experimental data

Obtention and application of recovery coefficients in SUV values to quality control in PET equipment

International Nuclear Information System (INIS)

Oliveira, Cássio Miri; Sá, Lídia V. de; Santana, Priscila do Carmo; Mamede, Marcelo; Silva, Teógenes A. da

2017-01-01

The functional imaging technique Positron Emission Tomography (PET) using the radiopharmaceutical fluorodeoxyglucose ("1"8F-FDG) has been demonstrated an important role in the diagnosis and staging of cancer tumors. However, the standard uptake values (SUV) quantification of a 'lesion' or a hot spot is influenced by partial volume effects (PVE). This is particularly important for evaluating solid tumour response to therapy, where SUV quantification could indicate treatment efficiency. The objective of this study was to evaluate the efficiency of "1"8F-FDG uptake correction in two image quantification modes (SUVmaximum and SUVmedium) through recovery coefficients (RC) application. The NEMA/IEC Body Phantom simulator was used and tested for an activity ratio lesion to background of 4:1, and at different acquisition times. The images quantification was performed with OsiriX® software. The obtained RCs were applied to the phantom images. The obtained SUVmedium values corrected by RCs presented satisfactory results, demonstrating small differences (1.1% a 2.3%) in relation to previously known SUVreference values. This did not occur for corrected SUVmaximum values where differences of up to 27.0% were observed between these and SUVreference values. These results demonstrate that the PVE correction by SUVmedium can more adequate to evaluate tumor's uptake. Therefore, this parameter should be used for equipment quality control in order to evaluate the response and degree of agreement between equipment. (author)

PODAAC-GRMEA-20C05

Data.gov (United States)

National Aeronautics and Space Administration — This dataset contains estimates of Earths static field geopotential derived from the Gravity Recovery and Climate Experiment (GRACE) mission measurements, produced...

Tests and comparisons of gravity models.

Science.gov (United States)

Marsh, J. G.; Douglas, B. C.

1971-01-01

Optical observations of the GEOS satellites were used to obtain orbital solutions with different sets of geopotential coefficients. The solutions were compared before and after modification to high order terms (necessary because of resonance) and were then analyzed by comparing subsequent observations with predicted trajectories. The most important source of error in orbit determination and prediction for the GEOS satellites is the effect of resonance found in most published sets of geopotential coefficients. Modifications to the sets yield greatly improved orbits in most cases. The results of these comparisons suggest that with the best optical tracking systems and gravity models, satellite position error due to gravity model uncertainty can reach 50-100 m during a heavily observed 5-6 day orbital arc. If resonant coefficients are estimated, the uncertainty is reduced considerably.

PODAAC-GRGAC-20C05

Data.gov (United States)

National Aeronautics and Space Administration — FOR EXPERT USE ONLY. This dataset contains estimates of Earths geopotential field derived from the Gravity Recovery and Climate Experiment (GRACE) mission...

PODAAC-GRGAC-2WG05

Data.gov (United States)

National Aeronautics and Space Administration — FOR EXPERT USE ONLY. This dataset contains estimates of Earths geopotential field derived from the Gravity Recovery and Climate Experiment (GRACE) mission...

PODAAC-GRGAB-20J15

Data.gov (United States)

National Aeronautics and Space Administration — FOR EXPERT USE ONLY. This dataset contains estimates of Earth's geopotential field derived from the Gravity Recovery and Climate Experiment (GRACE) mission...

PODAAC-GRGAA-2WG05

Data.gov (United States)

National Aeronautics and Space Administration — FOR EXPERT USE ONLY. This dataset contains estimates of Earths geopotential field derived from the Gravity Recovery and Climate Experiment (GRACE) mission...

PODAAC-GRGAB-2WG05

Data.gov (United States)

National Aeronautics and Space Administration — FOR EXPERT USE ONLY. This dataset contains estimates of Earths geopotential field derived from the Gravity Recovery and Climate Experiment (GRACE) mission...

PODAAC-GRGAA-20J15

Data.gov (United States)

National Aeronautics and Space Administration — FOR EXPERT USE ONLY. This dataset contains estimates of Earths geopotential field derived from the Gravity Recovery and Climate Experiment (GRACE) mission...

DCCO and SCCO: measurements of diffusion coefficients and of thermodiffusion in microgravity; DCCO et SCCO: mesures de coefficients de diffusion et de thermodiffusion en microgravite

Energy Technology Data Exchange (ETDEWEB)

Legros, J.C.; Van Vaerenbergh, S.; Dubois, F.; Decroly, Y. [Universite Libre de Bruxelles (Belgium); Montel, F. [ELF-Aquitaine Production, 64 - Pau (France); Goodman, S. [C-CORE, New Foundland, (Canada); Bekaert, G. [SABCA, Bruxelles (Belgium); Van Ransbeek, E. [IASB-BIRA, Bruxelles (Belgium)

1996-12-31

Measurements of diffusion coefficients of ternary systems and of thermodiffusion coefficients of multicomponent systems, including crude oils, have been undertaken by MRC and Elf-Aquitaine. The experiments DCCO and SCCO (respectively Diffusion and Soret Coefficients of Crude Oils) will be performed in 1997 and 1998 in GAS containers on the Space Shuttle. The 9 systems of DCCO are analyzed by Mach-Zehnder bicolor interferometry. The samples of the 18 systems of SCCO, among which three at 300 bars and at a mean temperature of 60 deg. C, will be analyzed after recovery on ground by a chromatographic technique. Such measurements performed in microgravity, like the measurements of Soret coefficients of binary solutions performed in the microgravity SCM experiments, are necessary reference measurements. (authors) 12 refs.

High temperature heat recovery systems; Les recuperateurs de chaleur a haute temperature

Energy Technology Data Exchange (ETDEWEB)

Martin, L.

2003-07-15

A state-of-the-art of high temperature heat recovery systems has been made to highlight the advantages of recovery in different energy cycles, and to compare the different geometries, materials and fabrication processes used by the different manufacturers. This leads to define the criteria that a heat recovery system must satisfy in gas turbine cogeneration applications. The pre-dimensioning of a recovery system has been performed in order to compare different geometries and to evaluate them with respect to the criteria defined in the bibliographic study. Finally, the new configuration of the 'Claire' loop has permitted to experimentally characterize a recovery system with an innovative technology based on an helical geometry. These tests have permitted to obtain the global data of the recovery system (efficiency, pressure drop, global exchange coefficient, friction coefficient, velocity and temperature profiles) and to position it with respect to the criteria defined in the bibliographic study. (J.S.)

An attempt to link the Brazilian Height System to a World Height System

Directory of Open Access Journals (Sweden)

V. G. Ferreira

Full Text Available This paper deals with the geopotential approach to investigate the present Brazilian Height System (BHS. Geopotential numbers are derived from Global Positioning System (GPS satellite surveying and disturbing potential on selected benchmarks. A model for the disturbing potential can be obtained by an existing set of spherical harmonic coefficients such as the Earth Gravity Model 2008 (EGM08. The approach provides absolute evaluation of local normal geopotential numbers (aka spheropotential numbers related to a so-called World Height System (WHS. To test the validity of the proposed methodology, a numerical experiment was carried out related to a test region in Southern Brazil. The accuracy of the derived geopotential numbers was tested versus local normal geopotential numbers based on 262 GPS/leveling points. The root mean square error (RMSE value for metric offset of BHS derived from geopotential numbers and the disturbing potential modeling in the test area was estimated to be near 0.224 meters in the absolute view. Therefore, since these spheropotential numbers are referred to a local datum, these results of comparisons may be an indicator of the mean bias of local network due to the effect of local Sea Surface Topography (SSTop and possible offset between the unknown reference for the BHS and the quasigeoid model in the region.

Obtention and application of recovery coefficients in SUV values to quality control in PET equipment

Energy Technology Data Exchange (ETDEWEB)

Oliveira, Cássio Miri; Sá, Lídia V. de; Santana, Priscila do Carmo; Mamede, Marcelo; Silva, Teógenes A. da, E-mail: cassio.miri@unifesp.br, E-mail: lidia@ird.gov.br, E-mail: mamede.mm@gmail.com, E-mail: silvata@cdtn.br [Universidade Federal de Sao Paulo (UNIFESP), SP (Brazil). Departmento de Diagnose por Imagem; Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil); Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2017-11-01

The functional imaging technique Positron Emission Tomography (PET) using the radiopharmaceutical fluorodeoxyglucose ({sup 18}F-FDG) has been demonstrated an important role in the diagnosis and staging of cancer tumors. However, the standard uptake values (SUV) quantification of a 'lesion' or a hot spot is influenced by partial volume effects (PVE). This is particularly important for evaluating solid tumour response to therapy, where SUV quantification could indicate treatment efficiency. The objective of this study was to evaluate the efficiency of {sup 18}F-FDG uptake correction in two image quantification modes (SUVmaximum and SUVmedium) through recovery coefficients (RC) application. The NEMA/IEC Body Phantom simulator was used and tested for an activity ratio lesion to background of 4:1, and at different acquisition times. The images quantification was performed with OsiriX® software. The obtained RCs were applied to the phantom images. The obtained SUVmedium values corrected by RCs presented satisfactory results, demonstrating small differences (1.1% a 2.3%) in relation to previously known SUVreference values. This did not occur for corrected SUVmaximum values where differences of up to 27.0% were observed between these and SUVreference values. These results demonstrate that the PVE correction by SUVmedium can more adequate to evaluate tumor's uptake. Therefore, this parameter should be used for equipment quality control in order to evaluate the response and degree of agreement between equipment. (author)

Is the geopotential directly measurable (Gauss, Bruns, Einstein : Je li geopotencijal direktno mjerljiv? (Gaus, Bruns, Ajnštajn

Directory of Open Access Journals (Sweden)

Helmut Moritz

2016-12-01

Full Text Available It has been pointed out by the great Swedish geodesist Arne Bjerhammar and others around1985 that it is possible to replace the classical method of spirit leveling for determining differences of the geopotential by a much more direct and elegant method, measuring the frequency of atomic clocks. This is impossible by classical physics and requires methods of Einstein’s General Theory of Relativity. The principle is that the geopotential can be “felt” by the “proper time” of this theory, but there remained the problem that the measuring accuracies were unthinkably high in 1985 and even later. To get a leveling accuracy of 1 cm, we must measure these frequencies to a relative accuracy of 10-18. Reaching such accuracies provided a great challenge to high-precision time observation all over the world, from USA to China. Now it seems that the required frequency accuracy is being reached. The author tries to give a short introductory review accessible to geodetic students and surveyors. It is purely didactic. : Veliki švedski geodeta Arne Bjerhammar (i neki drugi, istakao je oko 1985. godine, da je klasičnu metodu geometrijskog nivelmana za određivanje razlika geopotencijala moguće zamijeniti mnogo direktnijom i elegantnom metodom, mjerenjem frekvencije atomskih satova. Ovo nije moguće metodama klasične fizike, te zahtijeva primjenu Ajnštajnove Teorije općeg relativiteta. Princip je da se geopotencijal može “osjetiti” pomoću “pravog vremena” ove teorije, ali ostaje problem što je tačnost mjerenja bila nezamisliva u 1985. godini, pa čak i poslije. Da bi se dobila tačnost nivelanja od 1 cm, frekvencije se moraju mjeriti s relativnom tačnošću od 10-18. Dostizanje ove tačnosti bio je ogroman izazov za sve svjetske opservatorije za visokoprecizno mjerenje vremena, od SAD do Kine. Čini se da je zahtijevana tačnost ipak dostignuta. Autor nastoji dati kratak, potpuno didaktički uvod, pristupačan studentima geodezije i

Gradient-based estimation of Manning's friction coefficient from noisy data

KAUST Repository

Calo, Victor M.

2013-01-01

We study the numerical recovery of Manning\\'s roughness coefficient for the diffusive wave approximation of the shallow water equation. We describe a conjugate gradient method for the numerical inversion. Numerical results for one-dimensional models are presented to illustrate the feasibility of the approach. Also we provide a proof of the differentiability of the weak form with respect to the coefficient as well as the continuity and boundedness of the linearized operator under reasonable assumptions using the maximal parabolic regularity theory. © 2012 Elsevier B.V. All rights reserved.

Gradient-based estimation of Manning's friction coefficient from noisy data

KAUST Repository

Calo, Victor M.; Collier, Nathan; Gehre, Matthias; Jin, Bangti; Radwan, Hany G.; Santillana, Mauricio

2013-01-01

We study the numerical recovery of Manning's roughness coefficient for the diffusive wave approximation of the shallow water equation. We describe a conjugate gradient method for the numerical inversion. Numerical results for one-dimensional models are presented to illustrate the feasibility of the approach. Also we provide a proof of the differentiability of the weak form with respect to the coefficient as well as the continuity and boundedness of the linearized operator under reasonable assumptions using the maximal parabolic regularity theory. © 2012 Elsevier B.V. All rights reserved.

Experimental investigation of factors affecting the absolute recovery coefficients in iodine-124 PET lesion imaging

International Nuclear Information System (INIS)

Jentzen, Walter

2010-01-01

The use of recovery coefficients (RCs) in 124 I PET lesion imaging is a simple method to correct the imaged activity concentration (AC) primarily for the partial-volume effect and, to a minor extent, for the prompt gamma coincidence effect. The aim of this phantom study was to experimentally investigate a number of various factors affecting the 124 I RCs. Three RC-based correction approaches were considered. These approaches differ with respect to the volume of interest (VOI) drawn, which determines the imaged AC and the RCs: a single voxel VOI containing the maximum value (maximum RC), a spherical VOI with a diameter of the scanner resolution (resolution RC) and a VOI equaling the physical object volume (isovolume RC). Measurements were performed using mainly a stand-alone PET scanner (EXACT HR + ) and a latest-generation PET/CT scanner (BIOGRAPH mCT). The RCs were determined using a cylindrical phantom containing spheres or rotational ellipsoids and were derived from images acquired with a reference acquisition protocol. For each type of RC, the influence of the following factors on the RC was assessed: object shape, background activity spill in and iterative image reconstruction parameters. To evaluate the robustness of the RC-based correction approaches, the percentage deviation between RC-corrected and true ACs was determined from images acquired with a clinical acquisition protocol of different AC regimes. The observed results of the shape and spill-in effects were compared with simulation data derived from a convolution-based model. The study demonstrated that the shape effect was negligible and, therefore, was in agreement with theoretical expectations. In contradiction to the simulation results, the observed spill-in effect was unexpectedly small. To avoid variations in the determination of RCs due to reconstruction parameter changes, image reconstruction with a pixel length of about one-third or less of the scanner resolution and an OSEM 1 x 32 algorithm

Recent variations in geopotential height associated with West African monsoon variability

Science.gov (United States)

Okoro, Ugochukwu K.; Chen, Wen; Nath, Debashis

2018-02-01

In the present study, the atmospheric circulation patterns associated with the seasonal West Africa (WA) monsoon (WAM) rainfall variability has been investigated. The observational rainfall data from the Climatic Research Unit (CRU) and atmospheric fields from the National Center for Environmental Prediction (NCEP) reanalysis 2, from 1979 to 2014, have been used. The rainfall variability extremes, classified as wet or dry years, are the outcomes of simultaneous 6-month SPI at the three rainfall zones, which shows increasing trends [Guinea Coast (GC = 0.012 year-1), Eastern Sudano Sahel (ESS = 0.045 year-1) and Western Sudano Sahel (WSS = 0.056 year-1) from Sen's slope]; however, it is significant only in the Sahel region (α = 0.05 and α = 0.001 at ESS and WSS, respectively, from Mann-Kendall test). The vertical profile of the geopotential height (GpH) during the wet and dry years reveals that the 700 hPa anomalies show remarkable pattern at about 8°N to 13°N. This shows varying correlation with the zonal averaged vertically integrated moisture flux convergence and rainfall anomalies, respectively, as well as the oceanic pulsations indexes [Ocean Nino Index (ONI) and South Atlantic Ocean dipole index (SAODI), significant from t test], identified as precursors to the Sahel and GC rainfall variability respectively. The role of GpH anomalies at 700 hPa has been identified as the facilitator to the West African Westerly Jet's input to the moisture flux transported over the WA. This is a new perspective of the circulation processes associated with WAM and serves as a basis for modeling investigations.

Tectonic Interpretation of CHAMP Geopotential Data over the Northern Adriatic Sea.

Science.gov (United States)

Taylor, P. T.; Kim, H. R.; Mayer-Gürr, T.

2006-05-01

Recent aeromagnetic anomaly compilations (Chiappini et al., 2000 and Tontini et al., 2004) show a large positive (>700 nT) northwest-southeast trending magnetic anomaly off the Dalmatian coast. Unfortunately these aeromagnetic data cover only a part of this anomaly. We wanted to investigate if this large magnetic anomaly could be detected at satellite altitude and what is the extent and source of this feature. Therefore, magnetic and gravity anomaly maps were made from the CHAMP geopotential data, measured at the current low altitude of 345-350 km over the northern Adriatic Sea. We made the magnetic anomaly map over this relatively small region using 36 descending and 85 ascending orbits screened to be at the lowest altitude and the most magnetically quietest data. We removed the main field component (i.e., IGRF-10 up to degree and order 13) and then demeaned individual tracks and subtracted a second order polynomial to remove regional and/or un-modeled external field features. The resulting map from these well-correlated anomalies revealed a positive magnetic anomaly (>2 nT). Reduction-to-the pole brought these CHAMP anomaly features into coincidence with the aeromagnetic data. Previously Cantini et al. (1999) compared the surface magnetic data with MAGSAT by continuing upward the former and downwards the latter to 100 km and found a good correlation for wavelengths of 300-500 km. We also investigated the CHAMP gravity data. They were reduced using the kinematic short-arc integration method (Ilk et al., 2005 and Mayer Gürr et al., 2005). However, no corresponding short-wavelength gravity anomaly was observed in our study area. This tectonically complex region is under horizontal stress and the source of the large magnetic anomaly can be modelled by an associated ophiolite melange.

Spectral evaluation of Earth geopotential models and an experiment ...

Indian Academy of Sciences (India)

the models and monitoring the improvements in gravity field recovery are required. This study assesses ... group from the Inter- national Gravity Field Service (IGFS) and the ..... the method, the process may therefore be iter- ated until the ...

Recovery of aroma compounds from orange essential oil

Directory of Open Access Journals (Sweden)

Haypek E.

2000-01-01

Full Text Available The objective of this work was to study the recovery of aroma compounds present in the orange essential oil using experimental data from CUTRALE (a Brazilian Industry of Concentrated Orange Juice. The intention was to reproduce the industrial unit and afterwards to optimize the recovery of aroma compounds from orange essential oil by liquid-liquid extraction. The orange oil deterpenation was simulated using the commercial software PRO/II 4.0 version 1.0. The UNIFAC model was chosen for the calculation of the activity coefficients.

Influence of fluid-attenuated inversion-recovery on stroke apparent diffusion coefficient measurements and its clinical application

Energy Technology Data Exchange (ETDEWEB)

Ni Jianming [Medical Imaging Department, Wuxi Second Hospital Affiliated Nanjing Medical University, 68 Zhong Shan Road, Wuxi, Jiangsu Province 214002 (China); Radiology Department, Huashan Hospital, Shanghai Medical College, Fudan University, 12 Urumqi Middle Road, Shanghai 200040 (China); Nuclear Medicine Department, Renji Hospital, Medical School of Jiaotong University, Dongfang Road 1630, Shanghai 200127 (China); Mogensen, Monique A. [Department of Radiology, Division of Neuroradiology, University of Southern California, Los Angeles, CA (United States); Chen Zengai [Radiology Department, Huashan Hospital, Shanghai Medical College, Fudan University, 12 Urumqi Middle Road, Shanghai 200040 (China); Nuclear Medicine Department, Renji Hospital, Medical School of Jiaotong University, Dongfang Road 1630, Shanghai 200127 (China); Shuang Chen; Shen Tianzhen [Radiology Department, Huashan Hospital, Shanghai Medical College, Fudan University, 12 Urumqi Middle Road, Shanghai 200040 (China); Huang Gang, E-mail: huang2802@163.co [Nuclear Medicine Department, Renji Hospital, Medical School of Jiaotong University, Dongfang Road 1630, Shanghai 200127 (China)

2010-08-15

Background and purpose: The application of a fluid-attenuated inversion-recovery pulse with a conventional diffusion-weighted MRI sequence (FLAIR DWI) decreases the partial volume effects from cerebrospinal fluid on apparent diffusion coefficient (ADC) measurements. For this reason, FLAIR DWI may be more useful in the evaluation of ischemic stroke, but few studies have looked at the effect of FLAIR on ADC measurements in this setting. This study quantitatively compares FLAIR DWI and conventional DWI in ischemic stroke of varying ages to assess the potential advantages of this technique. Methods: We respectively analyzed 139 DWI studies in patients with ischemic stroke with and without FLAIR at varying time points ranging from hyperacute to chronic. ADC values were measured in each lesion, as well as in the contralateral normal side. Comparisons were made between the ADC values obtained from the DWI sequences with and without FLAIR for both the lesion and the normal contralateral side. Results: The ADC measurements within the ischemic lesion were very similar on FLAIR DWI and conventional DWI for lesions less than 14 days old (p > 0.05), but were significantly decreased on FLAIR DWI for lesions between 15 and 30 days old and in lesions >31 days old (chronic stage) (p < 0.01). The contralateral ADC values were all significantly decreased on the FLAIR DWI sequence compared with conventional DWI (p < 0.01). Conclusions: The application of an inversion pulse does not significantly affect the ADC values for early stage ischemic stroke (less than 14 days from symptom onset), but results in a more accurate relative ADC measurement by reducing the cerebrospinal fluid partial volume effects of the normal contralateral side. In addition, combined with the conventional DWI, FLAIR DWI may be helpful in determining the age of ischemic lesions.

Numerical approach for enhanced oil recovery with surfactant flooding

Directory of Open Access Journals (Sweden)

Sadegh Keshtkar

2016-03-01

concentration and performance variable (cumulative oil recovery are studied. Finally, the comparison of oil recovery between water-flooding and surfactant-flooding was done. The results showed higher oil recovery with changes in capillary number when the partition coefficient is greater than unity. Increasing oil viscosity resulted in decreasing the oil recovery by changing in fractional flow. Moreover, it was concluded that the oil recovery was enhanced by increasing surfactant injection concentration. The oil recovery was increased when surfactant was injected to the system and this result was obtained by comparing water-flooding and surfactant-flooding.

Measurement of molecular diffusion coefficients of carbon dioxide and methane in heavy oil

Energy Technology Data Exchange (ETDEWEB)

Gu, Y.; Tharanivasan, A.K.; Yang, C. [Regina Univ., SK (Canada)

2004-07-01

Vapour extraction (VAPEX) is a solvent-based thermal recovery process which is considered to be a viable process for recovering heavy oil. In order to develop a solvent-based enhanced oil recovery (EOR) operation, it is necessary to know the rate and extent of oil mobilization by the solvent. The molecular diffusion coefficient of solvent gas in heavy oil must be known. In this study, the pressure decay method was used to measure the molecular diffusivity of a gas solvent in heavy oil by monitoring the decaying pressure. The pressure decay method is a non-intrusive method in which physical contact is made between the gas solvent and the heavy oil. The pressure versus time data are measured until the heavy oil reaches complete saturation. The diffusion coefficient can be determined from the measured data and a mathematical model. In this study, the molecular diffusion coefficients of carbon dioxide-heavy oil and methane-heavy oil systems were measured and compared. The experiments were performed in closed high-pressure cells at constant reservoir temperature. An analytical solution was also obtained to predict the pressure in the gas phase and for the boundary conditions at the solvent-heavy oil interface for each solvent. Solvent diffusivity was determined by finding the best match of the numerically predicted and experimentally measured pressures.

Enhanced recovery from surgery in the UK: an audit of the enhanced recovery partnership programme 2009-2012.

Science.gov (United States)

Simpson, J C; Moonesinghe, S R; Grocott, M P W; Kuper, M; McMeeking, A; Oliver, C M; Galsworthy, M J; Mythen, M G

2015-10-01

The UK Department of Health Enhanced Recovery Partnership Programme collected data on 24 513 surgical patients in the UK from 2009-2012. Enhanced Recovery is an approach to major elective surgery aimed at minimizing perioperative stress for the patient. Previous studies have shown Enhanced Recovery to be associated with reduced hospital length of stay and perioperative morbidity. In this national clinical audit, National Health Service hospitals in the UK were invited to submit patient-level data. The data regarding length of stay and compliance with each element of Enhanced Recovery protocols for colorectal, orthopaedic, urological and gynaecological surgery patients were analysed. The relationship between Enhanced Recovery protocol compliance and length of stay was measured. From 16 267 patients from 61 hospital trusts, three out of four surgical specialties showed Enhanced Recovery, compliance being weakly associated with shorter length of stay (correlation coefficients -0.18, -0.14, -0.25 in colorectal, orthopaedics and gynaecology respectively). At a cut-off of 80% compliance, good compliance was associated with two, one and three day reductions in median length of stay respectively in colorectal, orthopaedic and urological surgeries, with no saving in gynaecology. This study is the largest assessment of the relationship between Enhanced Recovery protocol compliance and outcome in four surgical specialties. The data suggest that higher compliance with an Enhanced Recovery protocol has a weak association with shorter length of stay. This suggests that changes in process, resulting from highly protocolised pathways, may be as important in reducing perioperative length of stay as any individual element of Enhanced Recovery protocols in isolation. © The Author 2015. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Heat recovery apparatus

International Nuclear Information System (INIS)

McFarland, I.

1987-01-01

Heat transfer is a living science and technical advances are constantly being made. However, in many cases, progress is limited by the equipment that is available on the market, rather than by knowledge of the heat transfer process. A case in point is the design of economizers: in such equipment a small quantity of water (with a relatively good heat transfer coefficient) is heated by a large quantity of low-pressure gas (with an inherently low heat transfer coefficient). As a first step in design finned tubing is used to lessen the discrepancy in coefficients. From this point, it becomes apparent that the equipment consists of a small number of tubes (to maintain good velocity on the water side) of considerable length (to provide sufficient area). In the process industries the base pressure, though low, may be in the region of 0.5 bar, and there is no convenient flue in which to place the heat recovery coil. It is therefore contained in a flat-sided enclosure, which is ill-fitted to pressure containment and is therefore reinforced with a plethora of structural sections. Such inelegant construction is quite common in North America; in Europe, cylindrical containments of vast size have been supplied for the same purposes. The real shortcoming is a successful marriage of different disciplines to produce reliable and efficient heat transfer equipment suitably contained

Some performance characteristics of a fluidized bed heat recovery unit

International Nuclear Information System (INIS)

Militzer, J.; Basu, P.; Adaikkappan, N.

1985-01-01

The advantages of using fluidized bed heat recovery units with diesel engines are well documented. Two of those are: significantly less tube fouling and heat transfer coefficient four to five time higher than that of conventional shell and tube heat exchangers. The high concentration of soot in the exhaust gases of diesel engines make fouling a major concern in design of any kind of heat recovery unit. In the experiment a conventional fluidized bed heat exchanger was connected to the exhaust of a diesel engine mounted on a dynamometer. With this arrangement it was possible to test the heat recovery unit under a wide range of operating conditions. The main objective of this experiment was the determination of the performance characteristics of the heat recovery unit, especially with reference to its heat transfer and fouling characteristics. (author)

Studying the Representation Accuracy of the Earth's Gravity Field in the Polar Regions Based on the Global Geopotential Models

Science.gov (United States)

Koneshov, V. N.; Nepoklonov, V. B.

2018-05-01

The development of studies on estimating the accuracy of the Earth's modern global gravity models in terms of the spherical harmonics of the geopotential in the problematic regions of the world is discussed. The comparative analysis of the results of reconstructing quasi-geoid heights and gravity anomalies from the different models is carried out for two polar regions selected within a radius of 1000 km from the North and South poles. The analysis covers nine recently developed models, including six high-resolution models and three lower order models, including the Russian GAOP2012 model. It is shown that the modern models determine the quasi-geoid heights and gravity anomalies in the polar regions with errors of 5 to 10 to a few dozen cm and from 3 to 5 to a few dozen mGal, respectively, depending on the resolution. The accuracy of the models in the Arctic is several times higher than in the Antarctic. This is associated with the peculiarities of gravity anomalies in every particular region and with the fact that the polar part of the Antarctic has been comparatively less explored by the gravity methods than the polar Arctic.

Simulation of stationary and transient geopotential-height eddies in January and July with a spectral general circulation model

International Nuclear Information System (INIS)

Malone, R.C.; Pitcher, E.J.; Blackmon, M.L.; Puri, K.; Bourke, W.

1984-01-01

We examine the characteristics of stationary and transient eddies in the geopotential-height field as simulated by a spectral general circulation model. The model possessess a realistic, but smootheed, topography. Two simulations with perpetual January and July forcing by climatological sea surface temperatures, sea ice, and insolation were extended to 1200 days, of which the final 600 days were used for the results in this study. We find that the stationary waves are well simulated in both seasons in the Northern Hemisphere, where strong forcing by orography and land-sea thermal contrast exists. However, in the Southern Hemisphere, where no continents are present in midlatitudes, the stationary waves have smaller amplitude than that observed in both seasons. In both hemispheres, the transient eddies are well simulated in the winter season but are too weak in the summer season. The model fails to generate a sufficiently intense summertime midlatitude jet in either hemisphere, and this results in a low level of transient activity. The variance in the tropical troposphere is very well simulated. We examine the geographical distribution and vertical structure of the transient eddies. Fourier analysis in zonal wavenumber and temporal filtering are used to display the wavelength and frequency characteristics of the eddies

Recovery of carrier-free gold-195

International Nuclear Information System (INIS)

Iofa, B.Z.; Ivanova, N.A.

1995-01-01

It is known that gold(III) is readily extracted from nitric acid solutions with ethers. The authors have studied extraction of trace amounts of gold(III) from nitric acid solutions with diethyl and diisopropyl ethers in the presence of significant excess of Pt(IV). Distribution coefficients of gold(III) were measured radiometrically using carrier-free gold-195 or spectrophotometrically in the presence of platinum(IV). Very high coefficients of gold separation from platinum may be achieved. Preliminary experiments have shown that zinc-65 was not extracted with ethers from nitric acid solutions. As an extraction system, the authors have chosen the system 10 M HNO 3 -diisopropyl ether. After model experiments, the authors have performed recovery of carrier-free gold-195 from a real platinum target irradiated with protons in a cyclotron

Relationships over time of subjective and objective elements of recovery in persons with schizophreni

DEFF Research Database (Denmark)

Jørgensen, Rikke; Zoffmann, Vibeke; Munk-Jørgensen, Povl

2015-01-01

of symptoms with four assessments of self-reports of subjective aspects of recovery. Participants were 101 outpatients with schizophrenia. Symptoms were assessed with the Positive and Negative Syndrome Scale (PANSS) while subjective recovery was assessed with the Recovery Assessment Scale (RAS). Separate......Recovery from schizophrenia involves both subjective elements such as self-appraised wellness and objective elements such as symptom remission. Less is known about how they interact. To explore this issue, this study examined the relationship over the course of 1 year of four assessments...... Pearson׳s or Spearman׳s rank׳s correlation coefficients, calculated at all four measurement points, revealed the total symptom score was linked with lower levels of overall self-recovery at all four measurement points. The PANSS emotional discomfort subscale was linked with self-reported recovery at all...

Changes of the temperature coefficients of the characteristics which accompany degradation and recovery of a-Si solar cells; A-Si taiyo denchi no hikari (denryu) rekka oyobi kaifuku ni tomonau tokusei ondo keisu no henka

Energy Technology Data Exchange (ETDEWEB)

Yanagisawa, T; Koyanagi, T; Nakamura, K; Takahisa, K; Kojima, T [electrotechnical Laboratory, Tsukuba (Japan)

1996-10-27

Pursuant to the measuring of temperature dependency of the characteristics such as conversion efficiency, during the process of degradation in a-Si solar cells due to light and electric current and the process of recovery by annealing, this paper describes changes in temperature coefficients, correlation between the characteristic parameters and the degradation, and the results of the examination of their characteristics. The conversion efficiency {mu} degraded approximately by 45% of the initial value each by the irradiation under a light intensity with 3 SUN accelerated and by the infusion of current at 20mA/cm{sup 2}; and then, the efficiency recovered to 70-75% of the degradation by subsequent annealing. In addition, in the temperature dependency at 80{degree}C against at 20{degree}C, Isc slightly increased while Vcc greatly decreased. This slight increase in Isc was mainly due to the decrease in the width of the forbidden band, while the decrease in Vcc was due to the increase in the reverse saturation current. The temperature dependency of {mu}N was negative, becoming small in accordance with the degradation. The temperature dependency of FF/FFO was negative initially both in light and current, but it decreased with the degradation and turned to positive. The temperature coefficients of I-V parameters reversibly changed corresponding to the degradation and recovery of these parameters and stayed in a good correlation. 7 refs., 8 figs., 1 tab.

Study on a heat recovery system for the thermal power plant utilizing air cooling island

International Nuclear Information System (INIS)

Sun, Jian; Fu, Lin; Sun, Fangtian; Zhang, Shigang

2014-01-01

A new heat recovery system for CHP (combined heat and power) systems named HRU (heat recovery unit) is presented, which could recover the low grade heat of exhausted steam from the turbine at the thermal power plant directly. Heat recovery of exhausted steam is often accomplished by recovering the heat of cooling water in current systems. Therefore, two processes of heat transfer is needed at least. However, exhausted steam could be condensed in the evaporator of HRU directly, which reduce one process of heat transfer. A special evaporator is designed condense the exhausted steam directly. Simulated results are compared to experiments, which could include the calculation of heat transfer coefficients of different parts of HRU. It is found that about 25Mw of exhausted steam is recovered by this system. HRU could be promising for conventional CHP systems, which could increase the total energy efficiency obviously and enlarge the heating capacity of a built CHP system. - Highlights: • A new heat recovery system for thermal power plant is presented. • A mathematical model including heat transfer coefficients calculation is given. • This heat recovery system is experimented at a thermal power plant. • Performances of this system under different working conditions are simulated

First-principles study on mono-vacancy self diffusion and recovery in tungsten crystal

International Nuclear Information System (INIS)

Wen, Shu long; Chen, Ji ming; Liu, Xiang; Zhu, Hao; Chang, Hong yan; Huang, Zheng; Pan, Min; Zhao, Yong

2016-01-01

Highlights: • The migration barrier energy E_m of vacancy indicated that the optimum diffusion paths would exist in the diffusion process. • The Frenkel pair’s recovery had a close correlation with the “I–V” distance and within a range of 1.86–2.08 eV. • The self-recovery region has an ellipsoid profile with the semiminor axis of 2.7 Å and the semimajor axis of 5.5 Å. • The probability for the vacancy migration was closely assosiated with the E_m and the working temperature. - Abstract: The point defects behavior becomes one of the most basic issues under the challenge of fusion environment. The recovery mechanisms of Frenkel pair defects and the self-diffusion coefficient of mono-vacancy in bulk bcc tungsten were researched by the first principle calculations. The calculation of migration energy curves for SIAs indicated that the process of the Frenkel pair recovery had a close correlation with the “I–V” distance, and the migration barrier energies E_m was within a limit range of 1.86–2.08 eV. It was found that the self-recovery region had an ellipsoid profile with the semiminor axis of 2.7 Å and the semimajor axis of 5.5 Å. The self-diffusion coefficients of the mono-vacancy were calculated and the results showed that the probability for the vacancy migration was not only associated with the E_m but also the temperature being challenged.

Ultra-low friction and excellent elastic recovery of fullerene-like ...

Indian Academy of Sciences (India)

2017-08-24

Aug 24, 2017 ... a high elastic recovery (∼90%), ultra-low friction coefficient (∼0.019) and low wear rate ... Y Meng et al .... [3] Liu D G, Tu J P, Gu C D, Hong C F, Chen R and Yang W S ... [7] Cumings J and Zettl A 2000 Science 289 602.

Characteristics of gravity signal and loading effect in China

Directory of Open Access Journals (Sweden)

Shuang Yi

2015-07-01

Full Text Available The complex geographical environment in China makes its gravity signals miscellaneous. This work gives a comprehensive representation and explanation in secular trend of gravity change in different regions, the key features of which include positive trend in inner Tibet Plateau and South China and negative trend in North China plain and high mountain Asia (HMA. We also present the patterns of amplitudes and phases of annual and semiannual change. The mechanism underlying the semiannual period is explicitly discussed. The displacement in three directions expressed in terms of geo-potential spherical coefficients and load Love numbers are given. A case study applied with these equations is presented. The results show that Global Positioning System (GPS observations can be used to compare with Gravity Recovery and Climate Experiment (GRACE derived displacement and the vertical direction has a signal-noise-ratio of about one order of magnitude larger than the horizontal directions.

Laser Rate Equation Based Filtering for Carrier Recovery in Characterization and Communication

DEFF Research Database (Denmark)

Piels, Molly; Iglesias Olmedo, Miguel; Xue, Weiqi

2015-01-01

We formulate a semiconductor laser rate equationbased approach to carrier recovery in a Bayesian filtering framework. Filter stability and the effect of model inaccuracies (unknown or un-useable rate equation coefficients) are discussed. Two potential application areas are explored: laser...... characterization and carrier recovery in coherent communication. Two rate equation based Bayesian filters, the particle filter and extended Kalman filter, are used in conjunction with a coherent receiver to measure frequency noise spectrum of a photonic crystal cavity laser with less than 20 nW of fiber...

Uranium recovery from low-level aqueous sources

International Nuclear Information System (INIS)

Kelmers, A.D.; Goeller, H.E.

1981-03-01

The aqueous sources of soluble uranium were surveyed and evaluated in terms of the uranium geochemical cycle in an effort to identify potential unexploited resources. Freshwater sources appeared to be too low in uranium content to merit consideration, while seawater, although very dilute (approx. 3.3 ppB), contains approx. 4 x 10 9 metric tons of uranium in all the world's oceans. A literature review of recent publications and patents concerning uranium recovery from seawater was conducted. Considerable experimental work is currently under way in Japan; less is being done in the European countries. An assessment of the current state of technology is presented in this report. Repeated screening programs have identified hydrous titanium oxide as the most promising candidate absorbent. However, some of its properties such as distribution coefficient, selectivity, loading, and possibly stability appear to render its use inadequate in a practical recovery system. Also, various assessments of the energy efficiency of pumped or tidal power schemes for contacting the sorbent and seawater are in major disagreement. Needed future research and development tasks are discussed. A fundamental sorbent development program to greatly improve sorbent properties would be required to permit practical recovery of uranium from seawater. Major unresolved engineering aspects of such recovery systems are also identified and discussed

Temporal variations in the second-degree stokes tesseral geopotential coefficients from TOPEX/Poseidon altimetry

Czech Academy of Sciences Publication Activity Database

Burša, Milan; Kenyon, S.; Kouba, J.; Šíma, Zdislav; Vatrt, V.; Vítek, V.; Vojtíšková, M.

2003-01-01

Roč. 93, č. 1 (2003), s. 37-64 ISSN 0167-9295 Institutional research plan: CEZ:AV0Z1003909 Keywords : T/P altimery * stokes 2-nd degree tesseral coeficients Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 0.418, year: 2003

First-principles study on mono-vacancy self diffusion and recovery in tungsten crystal

Energy Technology Data Exchange (ETDEWEB)

Wen, Shu long [Key Laboratory of Advanced Technology of Materials (Ministry of Education), Superconductivity and New Energy R& D Ceter, Southwest JiaoTong University, Chengdu, Sichuan 610031 (China); Chen, Ji ming; Liu, Xiang [Fusion Science of Southwestern Institute of Physics, Chengdu, Sichuan 610041 (China); Zhu, Hao; Chang, Hong yan [Key Laboratory of Advanced Technology of Materials (Ministry of Education), Superconductivity and New Energy R& D Ceter, Southwest JiaoTong University, Chengdu, Sichuan 610031 (China); Huang, Zheng, E-mail: zhhuang@swjtu.edu.cn [Key Laboratory of Advanced Technology of Materials (Ministry of Education), Superconductivity and New Energy R& D Ceter, Southwest JiaoTong University, Chengdu, Sichuan 610031 (China); Pan, Min, E-mail: mpan@swjtu.edu.cn [Key Laboratory of Advanced Technology of Materials (Ministry of Education), Superconductivity and New Energy R& D Ceter, Southwest JiaoTong University, Chengdu, Sichuan 610031 (China); Western Superconducting Technologies Co., Ltd., Xi’an, Shanxi 710018 (China); Zhao, Yong [Key Laboratory of Advanced Technology of Materials (Ministry of Education), Superconductivity and New Energy R& D Ceter, Southwest JiaoTong University, Chengdu, Sichuan 610031 (China)

2016-11-01

Highlights: • The migration barrier energy E{sub m} of vacancy indicated that the optimum diffusion paths would exist in the diffusion process. • The Frenkel pair’s recovery had a close correlation with the “I–V” distance and within a range of 1.86–2.08 eV. • The self-recovery region has an ellipsoid profile with the semiminor axis of 2.7 Å and the semimajor axis of 5.5 Å. • The probability for the vacancy migration was closely assosiated with the E{sub m} and the working temperature. - Abstract: The point defects behavior becomes one of the most basic issues under the challenge of fusion environment. The recovery mechanisms of Frenkel pair defects and the self-diffusion coefficient of mono-vacancy in bulk bcc tungsten were researched by the first principle calculations. The calculation of migration energy curves for <111> SIAs indicated that the process of the Frenkel pair recovery had a close correlation with the “I–V” distance, and the migration barrier energies E{sub m} was within a limit range of 1.86–2.08 eV. It was found that the self-recovery region had an ellipsoid profile with the semiminor axis of 2.7 Å and the semimajor axis of 5.5 Å. The self-diffusion coefficients of the mono-vacancy were calculated and the results showed that the probability for the vacancy migration was not only associated with the E{sub m} but also the temperature being challenged.

GRAVTool, a Package to Compute Geoid Model by Remove-Compute-Restore Technique

Science.gov (United States)

Marotta, G. S.; Blitzkow, D.; Vidotti, R. M.

2015-12-01

Currently, there are several methods to determine geoid models. They can be based on terrestrial gravity data, geopotential coefficients, astro-geodetic data or a combination of them. Among the techniques to compute a precise geoid model, the Remove-Compute-Restore (RCR) has been widely applied. It considers short, medium and long wavelengths derived from altitude data provided by Digital Terrain Models (DTM), terrestrial gravity data and global geopotential coefficients, respectively. In order to apply this technique, it is necessary to create procedures that compute gravity anomalies and geoid models, by the integration of different wavelengths, and that adjust these models to one local vertical datum. This research presents a developed package called GRAVTool based on MATLAB software to compute local geoid models by RCR technique and its application in a study area. The studied area comprehends the federal district of Brazil, with ~6000 km², wavy relief, heights varying from 600 m to 1340 m, located between the coordinates 48.25ºW, 15.45ºS and 47.33ºW, 16.06ºS. The results of the numerical example on the studied area show the local geoid model computed by the GRAVTool package (Figure), using 1377 terrestrial gravity data, SRTM data with 3 arc second of resolution, and geopotential coefficients of the EIGEN-6C4 model to degree 360. The accuracy of the computed model (σ = ± 0.071 m, RMS = 0.069 m, maximum = 0.178 m and minimum = -0.123 m) matches the uncertainty (σ =± 0.073) of 21 points randomly spaced where the geoid was computed by geometrical leveling technique supported by positioning GNSS. The results were also better than those achieved by Brazilian official regional geoid model (σ = ± 0.099 m, RMS = 0.208 m, maximum = 0.419 m and minimum = -0.040 m).

Short guide to direct gravitational field modelling with Hotine's equations

Czech Academy of Sciences Publication Activity Database

Sebera, Josef; Wagner, C. A.; Bezděk, Aleš; Klokočník, Jaroslav

2013-01-01

Roč. 87, č. 3 (2013), s. 223-238 ISSN 0949-7714 R&D Projects: GA MŠk(CZ) LC506 Grant - others:ESA(XE) ESA- PECS projec No. C98056 Institutional support: RVO:67985815 Keywords : geopotential coefficients * spherical harmonics * acceleration vector Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 3.917, year: 2013

Octanol-water partition coefficients for predicting the effects of tannins in ruminant nutrition.

Science.gov (United States)

Mueller-Harvey, Irene; Mlambo, Victor; Sikosana, Joe L N; Smith, Tim; Owen, Emyr; Brown, Ron H

2007-07-11

Tannins can cause beneficial or harmful nutritional effects, but their great diversity has until now prevented a rational distinction between tannin structures and their nutritional responses. An attempt has been made to study this problem by examining the octanol-water solubilities of tannins. A relatively simple HPLC method has been developed for screening mixtures of plant tannins for their octanol-water partition coefficients (Kow coefficients). Tannins were isolated from the fruits and leaves of different Acacia, Calliandra, Dichrostachys, and Piliostigma species, which are known to produce beneficial or harmful effects. The Kow coefficients of these tannins ranged from 0.061 to 13.9, average coefficients of variation were 9.2% and recoveries were 107%. Acacia nilotica fruits and leaves had the highest Kow coefficients, that is, 2.0 and 13.9, respectively. These A. nilotica products also have high concentrations of tannins. The combined effects of high octanol solubilities and high tannin concentrations may explain their negative effects on animal nutrition and health. It is known that compounds with high octanol solubilities are more easily absorbed into tissues, and it is, therefore, proposed that such compounds are more likely to cause toxicity problems especially if consumed in large quantities. According to the literature, tannins in human foods tend to have low Kow coefficients, and this was confirmed for the tannins in Piliostigma thonningii fruits. Therefore, unconventional feeds or browse products should be screened not only for their tannin concentrations but also for low octanol-water partition coefficients in order to identify nutritionally safe feeds and to avoid potentially toxic feeds.

1D Simulations for Microbial Enhanced Oil Recovery with Metabolite Partitioning

DEFF Research Database (Denmark)

Nielsen, Sidsel Marie; Shapiro, Alexander; Michelsen, Michael Locht

2010-01-01

We have developed a mathematical model describing the process of microbial enhanced oil recovery (MEOR). The one-dimensional isothermal model comprises displacement of oil bywater containing bacteria and substrate for their feeding. The bacterial products are both bacteria andmetabolites....... The characteristics for the water phase saturation profiles and the oil recovery curves are elucidated. However, the effect from the surfactant is not necessarily restricted to influence only interfacial tension, but it can also be an approach for changing, e.g., wettability. The distribution coefficient determines...... the time lag, until residual oil mobilization is initialized. It has also been found that the final recovery depends on the distance from the inlet before the surfactant effect takes place. The surfactant effect position is sensitive to changes in maximum growth rate, and injection concentrations...

Interpretation of Nonlinear Well Loss Coefficients for Rorabaugh (1953) Method.

Science.gov (United States)

Kurtulus, B.; Yaylım, T. N.; Avşar

2016-12-01

Step drawdown test (SDT) are essential for hydrogeologist to determine aquifer loss and well loss parameters. In a SDT, different series of constant-discharges with incremental rates are conducted to obtain incremental drawdown into the pumping well. Pumping well efficiency (if the well is properly developed and designed), aquifer characteristics (transmissivity, storativity) and discharge-drawdown relationship can be derived from SDT. The well loss parameter directly associate with the well efficiency. The main problem is to determine the correct well loss parameter in order to estimate aquifer characteristics. Walton (1962) stated that the interpretation of the well efficiency is possible to determine the nonlinear head loss coefficient (C) with p equals to 2 and Walton (1962) presented a criteria that suggested the following terms: If C is less than 1800 m2/s5, the is properly developed and designed, If C is ranged from 1800 m2/s5 to 3600 m2/s5, the well has a mild deterioration, If C is greater than 3600 m2/s5, the well has a severe clogging. Until now, several well-known computer techniques such as Aqutesolv, AquiferWin32 , AquifertestPro can be found in the literature to evaluate well efficiency when exponential parameter (p) equals to 2. However, there exist a lack of information to evaluate well efficiency for different number of exponential parameter (p). Strategic Water Storage & Recovery (SWSR) Project in Liwa, Abu Dhabi is the leading and unique hydrogeology project in the world because of its both financial and scientific dimension. A total of 315 recovery wells have been drilled in pursuance of the scope of the SWSR project. A Universal Well Efficiency Criteria (UWEC) is developed using 315 Step Drawdown Test (SDT). UWEC is defined for different number of head loss equation coefficients. The results reveal that there is a strong correlation between non-linear well loss coefficient (C) and exponential parameter (p) up to a coefficient of determination

The Impact of Temporal Geopotential Variations on GPS

Science.gov (United States)

Melachroinos, Stavros; Lemoine, Frank G.; Zelensky, Nikita P.; Beckley, Brian D.; Chinn, Douglas S.; Nicholas, Joseph B.; McCarthy, John J.; Pennington, Teresa; Luthcke, Scott B.

2012-01-01

Lemoine et al. (2006) and Lemoine et al. (2010) showed that applying more detailed models of time-variable gravity (TVG) improved the quality of the altimeter satellite orbits (e.g. TOPEX/Poseidon, Jason-1, Jason-2). This modeling include application of atmospheric gravity derived from 6-hrly pressure fields obtained from the ECMWF and annual gravity variations to degree & order 20x20 in spherical harmonics derived from GRACE data. This approach allowed the development of a consistent geophysical model for application to altimeter satellite orbit determination from 1993 to 2011. In addition, we have also evaluated the impact of TVG modeling on the POD of Jason-1 and Jason-2 by application of a weekly degree & order four gravity coefficient time series developed using data from ten SLR & DORIS-tracked satellites from 1993 to 2011 (Lemoine et al., 2011).

Single image super-resolution based on compressive sensing and improved TV minimization sparse recovery

Science.gov (United States)

Vishnukumar, S.; Wilscy, M.

2017-12-01

In this paper, we propose a single image Super-Resolution (SR) method based on Compressive Sensing (CS) and Improved Total Variation (TV) Minimization Sparse Recovery. In the CS framework, low-resolution (LR) image is treated as the compressed version of high-resolution (HR) image. Dictionary Training and Sparse Recovery are the two phases of the method. K-Singular Value Decomposition (K-SVD) method is used for dictionary training and the dictionary represents HR image patches in a sparse manner. Here, only the interpolated version of the LR image is used for training purpose and thereby the structural self similarity inherent in the LR image is exploited. In the sparse recovery phase the sparse representation coefficients with respect to the trained dictionary for LR image patches are derived using Improved TV Minimization method. HR image can be reconstructed by the linear combination of the dictionary and the sparse coefficients. The experimental results show that the proposed method gives better results quantitatively as well as qualitatively on both natural and remote sensing images. The reconstructed images have better visual quality since edges and other sharp details are preserved.

Discharge Coefficient of Rectangular Short-Crested Weir with Varying Slope Coefficients

Directory of Open Access Journals (Sweden)

Yuejun Chen

2018-02-01

Full Text Available Rectangular short-crested weirs are widely used for simple structure and high discharge capacity. As one of the most important and influential factors of discharge capacity, side slope can improve the hydraulic characteristics of weirs at special conditions. In order to systemically study the effects of upstream and downstream slope coefficients S1 and S2 on overflow discharge coefficient in a rectangular short-crested weir the Volume of Fluid (VOF method and the Renormalization Group (RNG κ-ε turbulence model are used. In this study, the slope coefficient ranges from V to 3H:1V and each model corresponds to five total energy heads of H0 ranging from 8.0 to 24.0 cm. Comparisons of discharge coefficients and free surface profiles between simulated and laboratory results display a good agreement. The simulated results show that the difference of discharge coefficients will decrease with upstream slopes and increase with downstream slopes as H0 increases. For a given H0, the discharge coefficient has a convex parabolic relation with S1 and a piecewise linearity relation with S2. The maximum discharge coefficient is always obtained at S2 = 0.8. There exists a difference between upstream and downstream slope coefficients in the influence range of free surface curvatures. Furthermore, a proposed discharge coefficient equation by nonlinear regression is a function of upstream and downstream slope coefficients.

Observed tidal braking in the earth/moon/sun system

Science.gov (United States)

Christodoulidis, D. C.; Smith, D. E.; Williamson, R. G.; Klosko, S. M.

1987-01-01

The low degree and order terms in the spherical harmonic model of the tidal potential were observed through the perturbations which are induced on near-earth satellite orbital motions. Evaluations of tracking observations from 17 satellites and a GEM-T1 geopotential model were used in the tidal recovery which was made in the presence of over 600 long-wavelength coefficients from 32 major and minor tides. Wahr's earth tidal model was used as a basis for the recovery of the ocean tidal terms. Using this tidal model, the secular change in the moon's mean motion due to tidal dissipation was found to be -25.27 + or - 0.61 arcsec/century squared. The estimation of lunar acceleration agreed with that observed from lunar laser ranging techniques (-24.9 + or - 1.0 arcsec/century squared), with the corresponding tidal braking of earth's rotation being -5.98 + or - 0.22 x 10 to the minus 22 rad/second squared. If the nontidal braking of the earth due to the observed secular change in the earth's second zonal harmonic is considered, satellite techniques yield a total value of the secular change of the earth's rotation rate of -4.69 + or - 0.36 x 10 to the minus 22 rad/second squared.

Development of two short measures for recovery and stress in sport.

Science.gov (United States)

Nässi, Anu; Ferrauti, Alexander; Meyer, Tim; Pfeiffer, Mark; Kellmann, Michael

2017-08-01

The Acute Recovery and Stress Scale (ARSS) and the Short Recovery and Stress Scale were first established in German for the purposes of monitoring athletes' current recovery-stress states in an economical and multidimensional manner. The aim of this paper is to document the development and initial validation of the English versions of these two psychometric monitoring tools. A total of 267 English-speaking athletes from a variety of team and individual sports participated in the study. The English versions demonstrated satisfactory internal consistency for both instruments (Cronbach α of .74-.89). Furthermore, good model fit was found for the eight scales of the ARSS, matching the structure and results of the German counterparts. Correlations among and between the scales reciprocate the theoretical constructs of stress and recovery, supporting the construct validity of the scales. Correlation coefficients within stress and recovery ranged between r s  = .29 and .68. The correlations between stress and recovery varied between r s  = -.29 and -.64. These constructs were further supported by correlations with the scores of the Recovery-Stress Questionnaire for Athletes, thereby showing convergent validity. The findings demonstrate initial validity and reliability of the two measures and reflect the results of the German versions. However, further research is needed before applying these scales in practical settings.

Measurement and prediction of aromatic solute distribution coefficients for aqueous-organic solvent systems. Final report

Energy Technology Data Exchange (ETDEWEB)

Campbell, J.R.; Luthy, R.G.

1984-06-01

Experimental and modeling activities were performed to assess techniques for measurement and prediction of distribution coefficients for aromatic solutes between water and immiscible organic solvents. Experiments were performed to measure distribution coefficients in both clean water and wastewater systems, and to assess treatment of a wastewater by solvent extraction. The theoretical portions of this investigation were directed towards development of techniques for prediction of solute-solvent/water distribution coefficients. Experiments were performed to assess treatment of a phenolic-laden coal conversion wastewater by solvent extraction. The results showed that solvent extraction for recovery of phenolic material offered several wastewater processing advantages. Distribution coefficients were measured in clean water and wastewater systems for aromatic solutes of varying functionality with different solvent types. It was found that distribution coefficients for these compounds in clean water systems were not statistically different from distribution coefficients determined in a complex coal conversion process wastewater. These and other aromatic solute distribution coefficient data were employed for evaluation of modeling techniques for prediction of solute-solvent/water distribution coefficients. Eight solvents were selected in order to represent various chemical classes: toluene and benzene (aromatics), hexane and heptane (alkanes), n-octanol (alcohols), n-butyl acetate (esters), diisopropyl ether (ethers), and methylisobutyl ketone (ketones). The aromatic solutes included: nonpolar compounds such as benzene, toluene and naphthalene, phenolic compounds such as phenol, cresol and catechol, nitrogenous aromatics such as aniline, pyridine and aminonaphthalene, and other aromatic solutes such as naphthol, quinolinol and halogenated compounds. 100 references, 20 figures, 34 tables.

Signal and noise in Gravity Recovery and Climate Experiment (GRACE) observed surface mass variations

NARCIS (Netherlands)

Schrama, E.J.O.; Wouters, B.; Lavallée, D.A.

2007-01-01

The Gravity Recovery and Climate Experiment (GRACE) product used for this study consists of 43 monthly potential coefficient sets released by the GRACE science team which are used to generate surface mass thickness grids expressed as equivalent water heights (EQWHs). We optimized both the smoothing

Recovery of uranium from seawater-status of technology and needed future research and development

International Nuclear Information System (INIS)

Kelmers, A.D.

1980-01-01

A survey of recent publications concerning uranium recovery from seawater shows that considerable experimental work in this area is currently under way in Japan, less in European countries. Repeated screening programs have identified hydrous titanium oxide as the most promising candidate adsorbent; however, many of its properties, such as distribution coefficient, selectivity, loading, and possibly stability, appear to fall far short of those required for a practical recovery system. In addition, various evaluations of the energy efficiency of pumped or tidal power schemes for contacting the sorbent and seawater are in serious disagreement. Needed future research and development tasks have been identified. A fundamental development program to achieve significantly improved adsorbent properties would be required to permit economical recovery of uranium from seawater. Unresolved engineering aspects of such recovery systems are also identified and discussed. 63 references

Computation of Clebsch-Gordan and Gaunt coefficients using binomial coefficients

International Nuclear Information System (INIS)

Guseinov, I.I.; Oezmen, A.; Atav, Ue

1995-01-01

Using binomial coefficients the Clebsch-Gordan and Gaunt coefficients were calculated for extremely large quantum numbers. The main advantage of this approach is directly calculating these coefficients, instead of using recursion relations. Accuracy of the results is quite high for quantum numbers l 1 , and l 2 up to 100. Despite direct calculation, the CPU times are found comparable with those given in the related literature. 11 refs., 1 fig., 2 tabs

Modelling and verification of once-through subcritical heat recovery steam generator

International Nuclear Information System (INIS)

Lee, Chae Soo; Choi, Young Jun; Kim, Hyun Gee; Yang, Ok Chul; Chong Chae Hon

2004-01-01

The once-through heat recovery steam generator is ideally matched to very high temperature and pressure, well into the supercritical range. Moreover this type of boiler is structurally simpler than drum type boiler. In drum type boiler, each tube play a well-defined role: water preheating, vaporization, superheating. Empirical equations are available to predict the average heat transfer coefficient for each regime. For once-through heat recovery steam generator, this is no more the case and mathematical models have to be adapted to account for the disappearance of drum type economizer, boiler, superheater. General equations have to be used for each tube of boiler, and actual heat transfer condition in each tube has to be identified

Solar tidal variations of coefficients of second harmonic of gravitational potential of Mercury

Science.gov (United States)

Ferrandiz, Jose; Barkin, Yury

2010-05-01

Variations of coefficients of the second harmonic of Mercury potential caused by the solar tides have been studied. In the paper we use analytical expressions for tidal variations of Stoks coefficients obtained for model of the elastic celestial body with concentric distributions of masses and elastic parameters (Love numbers) and their reduced form with using fundamental elastic parameter k2 of the Mercury. Taking into account the resonant properties of the Mercury motion variations of the Mercury potential coefficients we present in the form of Fourier series on the multiple of corresponding arguments of the Mercury orbital theory. Evaluations of the amplitudes and periods of observed variations of Mercury potential have been tabulated for base elastic model of the Mercury characterized by hypothetic elastic parameter (Love number) k2=0.37 (Dehant et al., 2005). Tidal variations of polar moment of inertia of the Mercury (due to tidal deformations) lead to remarkable variations of the Mercury rotation. Tidal variations of the Mercury axial rotation also have been determined and tabulated. From our results it follows that the tide periodic variations of gravitational coefficients of the Mercury in a few orders bigger then corresponding tidal variations of Earth's geopotential coefficients (Ferrandiz, Getino, 1993). Variations coefficients of the second harmonic of Mercury potential. These variations are determined by the known formulae for variations of coefficients of the second harmonic of geopotential (Ferrandiz, Getino, 1993). Here we present these formulae in some special form as applied to the considered problem about the Mercury tidal deformations: ( ) δJ2 = - 3Tα23-2, δC22 = T α21 - α22 -4, δS22 = T α1α2-2, δC21 = Tα1α3, δS21 = T α2α3. Here T = k2(M R3 -ma3 ) = 1.667 × 10-7 is a estimation of some conditional coefficient of tidal deformation of Mercury. m and Rare the mass and the mean radius of Mercury. Here we have used standard values of

Towards the Selection of an Optimal Global Geopotential Model for the Computation of the Long-Wavelength Contribution: A Case Study of Ghana

Directory of Open Access Journals (Sweden)

Caleb Iddissah Yakubu

2017-11-01

Full Text Available The selection of a global geopotential model (GGM for modeling the long-wavelength for geoid computation is imperative not only because of the plethora of GGMs available but more importantly because it influences the accuracy of a geoid model. In this study, we propose using the Gaussian averaging function for selecting an optimal GGM and degree and order (d/o for the remove-compute-restore technique as a replacement for the direct comparison of terrestrial gravity anomalies and GGM anomalies, because ground data and GGM have different frequencies. Overall, EGM2008 performed better than all the tested GGMs and at an optimal d/o of 222. We verified the results by computing geoid models using Heck and Grüninger’s modification and validated them against GPS/trigonometric data. The results of the validation were consistent with those of the averaging process with EGM2008 giving the smallest standard deviation of 0.457 m at d/o 222, resulting in an 8% improvement over the previous geoid model. In addition, this geoid model, the Ghanaian Gravimetric Geoid 2017 (GGG 2017 may be used to replace second-order class II leveling, with an expected error of 6.8 mm/km for baselines ranging from 20 to 225 km.

Coefficient estimates of negative powers and inverse coefficients for ...

Indian Academy of Sciences (India)

and the inequality is sharp for the inverse of the Koebe function k(z) = z/(1 − z)2. An alternative approach to the inverse coefficient problem for functions in the class S has been investigated by Schaeffer and Spencer [27] and FitzGerald [6]. Although, the inverse coefficient problem for the class S has been completely solved ...

Converting Sabine absorption coefficients to random incidence absorption coefficients

DEFF Research Database (Denmark)

Jeong, Cheol-Ho

2013-01-01

are suggested: An optimization method for the surface impedances for locally reacting absorbers, the flow resistivity for extendedly reacting absorbers, and the flow resistance for fabrics. With four porous type absorbers, the conversion methods are validated. For absorbers backed by a rigid wall, the surface...... coefficients to random incidence absorption coefficients are proposed. The overestimations of the Sabine absorption coefficient are investigated theoretically based on Miki's model for porous absorbers backed by a rigid wall or an air cavity, resulting in conversion factors. Additionally, three optimizations...... impedance optimization produces the best results, while the flow resistivity optimization also yields reasonable results. The flow resistivity and flow resistance optimization for extendedly reacting absorbers are also found to be successful. However, the theoretical conversion factors based on Miki's model...

Coefficient Alpha: A Reliability Coefficient for the 21st Century?

Science.gov (United States)

Yang, Yanyun; Green, Samuel B.

2011-01-01

Coefficient alpha is almost universally applied to assess reliability of scales in psychology. We argue that researchers should consider alternatives to coefficient alpha. Our preference is for structural equation modeling (SEM) estimates of reliability because they are informative and allow for an empirical evaluation of the assumptions…

A study of the chilean vertical network through global geopotential models and the cnes cls 2011 global mean sea surface

Directory of Open Access Journals (Sweden)

Henry Montecino Castro

Full Text Available Most aspects related to the horizontal component of the Geocentric Reference System for the Americas (SIRGAS have been solved. However, in the case of the vertical component there are still aspects of definition, national realizations and continental unification still not accomplished. Chile is no exception; due to its particular geographic characteristics, a number of tide gauges (TG had to be installed in the coast from which the leveling lines that compose the Chilean Vertical Network (CHVN were established. This study explored the offsets of the CHVN by two different approaches; one geodetic and one oceanographic. In the first approach, the offsets were obtained in relation to the following Global Geopotential Models (GGM: the satellite-only model (unbiased GO_CONS_gcf_2_tim_r3 derived from GOCE satellite mission; EGM2008 (combined-biased; and GOEGM08, combining information from the GO_CONS_gcf_2_tim_r3 in long wavelengths (n max~200 with the mean/short wavelengths of EGM2008 (n>200. In the oceanographic method, we used the CNES CLS 2011 Global Mean Sea surface and EIGEN_GRACE_5C GGM to obtain the values of MDT at the different TG. We also evaluated the CHVN in relation to different GGMs. The results showed consistency between the values obtained by the two methods at the TG of Valparaíso and Puerto Chacabuco. In terms of the evaluation of the GGM, GOEGM08 produced the best results.

Disaster Debris Recovery Database - Recovery

Data.gov (United States)

U.S. Environmental Protection Agency — The US EPA Disaster Debris Recovery Database (DDRD) promotes the proper recovery, recycling, and disposal of disaster debris for emergency responders at the federal,...

Recovery in soccer : part ii-recovery strategies.

Science.gov (United States)

Nédélec, Mathieu; McCall, Alan; Carling, Chris; Legall, Franck; Berthoin, Serge; Dupont, Gregory

2013-01-01

In the formerly published part I of this two-part review, we examined fatigue after soccer matchplay and recovery kinetics of physical performance, and cognitive, subjective and biological markers. To reduce the magnitude of fatigue and to accelerate the time to fully recover after completion, several recovery strategies are now used in professional soccer teams. During congested fixture schedules, recovery strategies are highly required to alleviate post-match fatigue, and then to regain performance faster and reduce the risk of injury. Fatigue following competition is multifactorial and mainly related to dehydration, glycogen depletion, muscle damage and mental fatigue. Recovery strategies should consequently be targeted against the major causes of fatigue. Strategies reviewed in part II of this article were nutritional intake, cold water immersion, sleeping, active recovery, stretching, compression garments, massage and electrical stimulation. Some strategies such as hydration, diet and sleep are effective in their ability to counteract the fatigue mechanisms. Providing milk drinks to players at the end of competition and a meal containing high-glycaemic index carbohydrate and protein within the hour following the match are effective in replenishing substrate stores and optimizing muscle-damage repair. Sleep is an essential part of recovery management. Sleep disturbance after a match is common and can negatively impact on the recovery process. Cold water immersion is effective during acute periods of match congestion in order to regain performance levels faster and repress the acute inflammatory process. Scientific evidence for other strategies reviewed in their ability to accelerate the return to the initial level of performance is still lacking. These include active recovery, stretching, compression garments, massage and electrical stimulation. While this does not mean that these strategies do not aid the recovery process, the protocols implemented up until

Recurrence relations between transformation coefficients of hyperspherical harmonics and their application to Moshinsky coefficients

International Nuclear Information System (INIS)

Raynal, J.

1976-01-01

Closed formulae and recurrence relations for the transformation of a two-body harmonic oscillator wave function to the hyperspherical formalism are given. With them Moshinsky or Smirnov coefficients are obtained from the transformation coefficients of hyperspheric harmonics. For these coefficients the diagonalization method of Talman and Lande reduces to simple recurrence relations which can be used directly to compute them. New closed formulae for these coefficients are also derived: they are needed to compute the two simplest coefficients which determine the sign for the recurrence relation. (Auth.)

Comparison of field-measured radon diffusion coefficients with laboratory-measured coefficients

International Nuclear Information System (INIS)

Lepel, E.A.; Silker, W.B.; Thomas, V.W.; Kalkwarf, D.R.

1983-04-01

Experiments were conducted to compare radon diffusion coefficients determined for 0.1-m depths of soils by a steady-state method in the laboratory and diffusion coefficients evaluated from radon fluxes through several-fold greater depths of the same soils covering uranium-mill tailings. The coefficients referred to diffusion in the total pore volume of the soils and are equivalent to values for the quantity, D/P, in the Generic Environmental Impact Statement on Uranium Milling prepared by the US Nuclear Regulatory Commission. Two soils were tested: a well-graded sand and an inorganic clay of low plasticity. For the flux evaluations, radon was collected by adsorption on charcoal following passive diffusion from the soil surface and also from air recirculating through an aluminum tent over the soil surface. An analysis of variance in the flux evaluations showed no significant difference between these two collection methods. Radon diffusion coefficients evaluated from field data were statistically indistinguishable, at the 95% confidence level, from those measured in the laboratory; however, the low precision of the field data prevented a sensitive validation of the laboratory measurements. From the field data, the coefficients were calculated to be 0.03 +- 0.03 cm 2 /s for the sand cover and 0.0036 +- 0.0004 cm 2 /s for the clay cover. The low precision in the coefficients evaluated from field data was attributed to high variation in radon flux with time and surface location at the field site

An Efficient Semi-fragile Watermarking Scheme for Tamper Localization and Recovery

Science.gov (United States)

Hou, Xiang; Yang, Hui; Min, Lianquan

2018-03-01

To solve the problem that remote sensing images are vulnerable to be tampered, a semi-fragile watermarking scheme was proposed. Binary random matrix was used as the authentication watermark, which was embedded by quantizing the maximum absolute value of directional sub-bands coefficients. The average gray level of every non-overlapping 4×4 block was adopted as the recovery watermark, which was embedded in the least significant bit. Watermarking detection could be done directly without resorting to the original images. Experimental results showed our method was robust against rational distortions to a certain extent. At the same time, it was fragile to malicious manipulation, and realized accurate localization and approximate recovery of the tampered regions. Therefore, this scheme can protect the security of remote sensing image effectively.

A parameterization scheme for the x-ray linear attenuation coefficient and energy absorption coefficient.

Science.gov (United States)

Midgley, S M

2004-01-21

A novel parameterization of x-ray interaction cross-sections is developed, and employed to describe the x-ray linear attenuation coefficient and mass energy absorption coefficient for both elements and mixtures. The new parameterization scheme addresses the Z-dependence of elemental cross-sections (per electron) using a simple function of atomic number, Z. This obviates the need for a complicated mathematical formalism. Energy dependent coefficients describe the Z-direction curvature of the cross-sections. The composition dependent quantities are the electron density and statistical moments describing the elemental distribution. We show that it is possible to describe elemental cross-sections for the entire periodic table and at energies above the K-edge (from 6 keV to 125 MeV), with an accuracy of better than 2% using a parameterization containing not more than five coefficients. For the biologically important elements 1 coefficients. At higher energies, the parameterization uses fewer coefficients with only two coefficients needed at megavoltage energies.

Influence of the sea surface temperature anomaly over the Indian Ocean in March on the summer rainfall in Xinjiang

Science.gov (United States)

Zhou, Yang; Huang, Anning; Zhao, Yong; Yang, Qing; Jiang, Jing; La, Mengke

2015-02-01

This study explores the relationship between the sea surface temperature over the Indian Ocean (IOSST) in March and the summer rainfall in Xinjiang. In the observations, the IOSST in March significantly correlates with the summer rainfall in Xinjiang with a correlation coefficient of about 0.49 during 1961-2007. This relationship is independent from the El Niño Southern Oscillation (ENSO), with a partial correlation coefficient of about 0.40-0.48 controlling for the ENSO indices from December to March. In addition to the observations, three sets of numerical sensitivity experiments are conducted with a regional climate model (RegCM4.3). The model results show that warm IOSST can excite a negative anomaly of geopotential height at 500 hPa over the Indian Ocean in March. This anomaly stays over the tropical Indian Ocean, and then propagates north to central Asia in June. Consequently, the anomalous wind associated with this geopotential height anomaly transports moisture from the Persian Gulf and the coast of Iran to Xinjiang, passing over Pakistan and the Tibetan Plateau. Therefore, the warm (cold) IOSST in March tends to cause the increase (decrease) of the summer rainfall over Xinjiang, especially in the Tian Shan and Kunlun Mountains.

Weyl q-coefficients for uq(3) and Racah q -coefficients for suq(2)

International Nuclear Information System (INIS)

Asherova, R.M.; Smirnov, Yu.F.; Tolstoy, V.N.

1996-01-01

With the aid of the projection-operator technique, the general analytic expression for the elements of the matrix that relates the U and T bases of an arbitrary finite-dimensional irreducible representation of the uq(3) quantum algebra (Weyl q-coefficients) is obtained for the case where the deformation parameter q is not equal to a square root of unity. The procedure for resummation of q-factorial expressions is used to prove that, modulo phase factors, these Weyl q-coefficients coincide with Racah q-coefficients for the suq(2) quantum algebra. It is also shown that, on the basis of one general formula, the q-analogs of all known general analytic expressions for the 6j symbols (and Racah coefficients) of the Lie algebras of the angular momentum can be obtained by using this resummation procedure. The symmetry properties of these q coefficients are discussed. The result is formulated in the following way: the general formulas for the q-6j symbols (Racah q-coefficients) of the suq(2) quantum algebra are obtained from the general formulas for the conventional 6j symbols (Racah coefficients) of the su(2) Lie algebra by replacing directly all factorials with q-factorials, the symmetry properties of the q-6j symbols being completely coincident with the symmetry properties of the conventional 6j symbols

The Truth About Ballistic Coefficients

OpenAIRE

Courtney, Michael; Courtney, Amy

2007-01-01

The ballistic coefficient of a bullet describes how it slows in flight due to air resistance. This article presents experimental determinations of ballistic coefficients showing that the majority of bullets tested have their previously published ballistic coefficients exaggerated from 5-25% by the bullet manufacturers. These exaggerated ballistic coefficients lead to inaccurate predictions of long range bullet drop, retained energy and wind drift.

Development of database on the distribution coefficient. 1. Collection of the distribution coefficient data

Energy Technology Data Exchange (ETDEWEB)

Takebe, Shinichi; Abe, Masayoshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

2001-03-01

The distribution coefficient is very important parameter for environmental impact assessment on the disposal of radioactive waste arising from research institutes. The literature survey in the country was mainly carried out for the purpose of selecting the reasonable distribution coefficient value on the utilization of this value in the safety evaluation. This report was arranged much informations on the distribution coefficient for inputting to the database for each literature, and was summarized as a literature information data on the distribution coefficient. (author)

A methodology for the geometric design of heat recovery steam generators applying genetic algorithms

International Nuclear Information System (INIS)

Durán, M. Dolores; Valdés, Manuel; Rovira, Antonio; Rincón, E.

2013-01-01

This paper shows how the geometric design of heat recovery steam generators (HRSG) can be achieved. The method calculates the product of the overall heat transfer coefficient (U) by the area of the heat exchange surface (A) as a function of certain thermodynamic design parameters of the HRSG. A genetic algorithm is then applied to determine the best set of geometric parameters which comply with the desired UA product and, at the same time, result in a small heat exchange area and low pressure losses in the HRSG. In order to test this method, the design was applied to the HRSG of an existing plant and the results obtained were compared with the real exchange area of the steam generator. The findings show that the methodology is sound and offers reliable results even for complex HRSG designs. -- Highlights: ► The paper shows a methodology for the geometric design of heat recovery steam generators. ► Calculates product of the overall heat transfer coefficient by heat exchange area as a function of certain HRSG thermodynamic design parameters. ► It is a complement for the thermoeconomic optimization method. ► Genetic algorithms are used for solving the optimization problem

Recovery from schizophrenia and the recovery model.

Science.gov (United States)

Warner, Richard

2009-07-01

The recovery model refers to subjective experiences of optimism, empowerment and interpersonal support, and to a focus on collaborative treatment approaches, finding productive roles for user/consumers, peer support and reducing stigma. The model is influencing service development around the world. This review will assess whether optimism about outcome from serious mental illness and other tenets of the recovery model are borne out by recent research. Remission of symptoms has been precisely defined, but the definition of 'recovery' is a more diffuse concept that includes such factors as being productive and functioning independently. Recent research and a large, earlier body of data suggest that optimism about outcome from schizophrenia is justified. A substantial proportion of people with the illness will recover completely and many more will regain good social functioning. Outcome is better for people in the developing world. Mortality for people with schizophrenia is increasing but is lower in the developing world. Working appears to help people recover from schizophrenia, and recent advances in vocational rehabilitation have been shown to be effective in countries with differing economies and labor markets. A growing body of research supports the concept that empowerment is an important component of the recovery process. Key tenets of the recovery model - optimism about recovery from schizophrenia, the importance of access to employment and the value of empowerment of user/consumers in the recovery process - are supported by the scientific research. Attempts to reduce the internalized stigma of mental illness should enhance the recovery process.

Extending the Constant Coefficient Solution Technique to Variable Coefficient Ordinary Differential Equations

Science.gov (United States)

Mohammed, Ahmed; Zeleke, Aklilu

2015-01-01

We introduce a class of second-order ordinary differential equations (ODEs) with variable coefficients whose closed-form solutions can be obtained by the same method used to solve ODEs with constant coefficients. General solutions for the homogeneous case are discussed.

Evaluation of Release-05 GRACE time-variable gravity coefficients over the ocean

Directory of Open Access Journals (Sweden)

D. P. Chambers

2012-10-01

Full Text Available The latest release of GRACE (Gravity Recovery and Climate Experiment gravity field coefficients (Release-05, or RL05 are evaluated for ocean applications. Data have been processed using the current methodology for Release-04 (RL04 coefficients, and have been compared to output from two different ocean models. Results indicate that RL05 data from the three Science Data Centers – the Center for Space Research (CSR, GeoForschungsZentrum (GFZ, and Jet Propulsion Laboratory (JPL – are more consistent among themselves than the previous RL04 data. Moreover, the variance of residuals with the output of an ocean model is 50–60% lower for RL05 data than for RL04 data. A more optimized destriping algorithm is also tested, which improves the results slightly. By comparing the GRACE maps with two different ocean models, we can better estimate the uncertainty in the RL05 maps. We find the standard error to be about 1 cm (equivalent water thickness in the low- and mid-latitudes, and between 1.5 and 2 cm in the polar and subpolar oceans, which is comparable to estimated uncertainty for the output from the ocean models.

Measuring Error Identification and Recovery Skills in Surgical Residents.

Science.gov (United States)

Sternbach, Joel M; Wang, Kevin; El Khoury, Rym; Teitelbaum, Ezra N; Meyerson, Shari L

2017-02-01

Although error identification and recovery skills are essential for the safe practice of surgery, they have not traditionally been taught or evaluated in residency training. This study validates a method for assessing error identification and recovery skills in surgical residents using a thoracoscopic lobectomy simulator. We developed a 5-station, simulator-based examination containing the most commonly encountered cognitive and technical errors occurring during division of the superior pulmonary vein for left upper lobectomy. Successful completion of each station requires identification and correction of these errors. Examinations were video recorded and scored in a blinded fashion using an examination-specific rating instrument evaluating task performance as well as error identification and recovery skills. Evidence of validity was collected in the categories of content, response process, internal structure, and relationship to other variables. Fifteen general surgical residents (9 interns and 6 third-year residents) completed the examination. Interrater reliability was high, with an intraclass correlation coefficient of 0.78 between 4 trained raters. Station scores ranged from 64% to 84% correct. All stations adequately discriminated between high- and low-performing residents, with discrimination ranging from 0.35 to 0.65. The overall examination score was significantly higher for intermediate residents than for interns (mean, 74 versus 64 of 90 possible; p = 0.03). The described simulator-based examination with embedded errors and its accompanying assessment tool can be used to measure error identification and recovery skills in surgical residents. This examination provides a valid method for comparing teaching strategies designed to improve error recognition and recovery to enhance patient safety. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

On the Kendall Correlation Coefficient

OpenAIRE

Stepanov, Alexei

2015-01-01

In the present paper, we first discuss the Kendall rank correlation coefficient. In continuous case, we define the Kendall rank correlation coefficient in terms of the concomitants of order statistics, find the expected value of the Kendall rank correlation coefficient and show that the later is free of n. We also prove that in continuous case the Kendall correlation coefficient converges in probability to its expected value. We then propose to consider the expected value of the Kendall rank ...

Correlation coefficients in neutron β-decay

International Nuclear Information System (INIS)

Byrne, J.

1978-01-01

The various angular and polarisation coefficients in neutron decay are the principal sources of information on the β-interaction. Measurements of the electron-neutrino angular correlation coefficient (a), the neutron-spin-electron-momentum correlation coefficient (A), the neutron-spin-neutrino-momentum correlation coefficient (B), and the triple correlation coefficient D and time-reversal invariance are reviewed and the results discussed. (U.K.)

Analysis of economic and environmental benefits of a new heat pump air conditioning system with a heat recovery device

Science.gov (United States)

Li, lingxue

2017-08-01

The paper designs a new wind-water cooling and heating water conditioner system, connects cooling tower with heat recovery device, which uses cooling water to completely remove the heat that does not need heat recollection, in order to ensure that the system can work efficiently with higher performance coefficient. After the test actual engineering operation, the system’s maximum cooling coefficient of performance can reach 3.5. Its maximum comprehensive coefficient of performance can reach 6.5. After the analysis of its economic and environmental, we conclude that the new system can save 89822 kw per year. It reflects energy-saving and environmental benefits of the cold and hot water air conditioning system.

Perspectives for tritium recovery from liquid Pb83Li17 alloy

International Nuclear Information System (INIS)

Pierini, G.

1983-01-01

A preliminary analysis has been made on the perspectives of tritium recovery from a blanket constituted by liquid Pb 83 Li 17 alloy, by investigating the Tsub(2g) 2T alloy thermodynamic behaviour and trying to individuate those chemico-physical characteristics of which knowledge is useful for the effective design of the apparatus. In the light of the recent work carried out on the systems, hydrogen and its isotopes with molten Li-Pb eutectics, it has been possible to individuate a fair reliability of the Sieverts constant for the T 2 -Pb 83 Li 17 system. As far as the kinetics of the tritium desorption process from the liquid phase are concerned, the hydrogen (and its isotopes) transfer rates across the liquid interphase have been evaluated. Even though in first approximation the diffusion coefficient of tritium in the molten alloy at 400 0 C has been found. Then, the processing equations of attractive tritium recovery systems have been presented, individuating the fundamental parameters and reporting an example of applied engineering of the desorption system in a packed column. None of these tritium recovery systems seem incompatible at the actual state of the research

Recovery in SoccerPart II—Recovery Strategies

OpenAIRE

Nedelec, Mathieu; McCall, Alan; Carling, Chris; Legall, Franck; Berthoin, Serge; Dupont, Grégory

2013-01-01

International audience; In the formerly published part I of this two-part review, we examined fatigue after soccer matchplay and recovery kinetics of physical performance, and cognitive, subjective and biological markers. To reduce the magnitude of fatigue and to accelerate the time to fully recover after completion, several recovery strategies are now used in professional soccer teams. During congested fixture schedules, recovery strategies are highly required to alleviate post-match fatigue...

The influence of diffusion and dispersion on heavy oil recovery by VAPEX

Energy Technology Data Exchange (ETDEWEB)

Alkindi, A. [Imperial College, London (United Kingdom); Muggeridge, A. [Society of Petroleum Engineers, London (United Kingdom)]|[Imperial College, London (United Kingdom); Al-Wahaibi, Y. [Society of Petroleum Engineers, Dubai (United Arab Emirates)]|[Sultan Qaboos Univ., Muscat (Oman)

2008-10-15

Heavy oil recovery using vapour extraction (VAPEX) is a promising improved oil recovery technique. However, field application of this process has been limited due to concerns that favourable laboratory recoveries may not scale up to the field level. Previous laboratory studies of VAPEX in porous media have obtained much higher production rates than predicted either by analytic models derived from Hele-Shaw experiments or numerical simulation. The difference between experimental and simulation models has been explained by assuming greater mixing between vapour and oil than would be expected from molecular diffusion. Convective dispersion is a plausible justification for this increase. This paper investigated the role of convective dispersion on oil recovery by VAPEX using a combination of well characterized laboratory experiments and numerical simulation. So that all mechanisms contributing to increased-mixing apart from convective dispersion were eliminated, a first contact miscible fluid system was used. Longitudinal and transverse dispersion coefficients were experimentally measured as a function of flow-rate and viscosity ratio. VAPEX drainage experiments were then conducted over a range of injection rates. The paper also discussed the comparison of laboratory measurements of oil drainage rates with those predicted by the Butler-Mokrys analytical model and numerical simulation using either molecular diffusion or convective dispersion. Last, the paper discussed the use of the numerical model in investigating the impact of rate, well separation, and reservoir geometry on recovery. 21 refs., 4 tabs., 12 figs.

Estimating temperature reactivity coefficients by experimental procedures combined with isothermal temperature coefficient measurements and dynamic identification

International Nuclear Information System (INIS)

Tsuji, Masashi; Aoki, Yukinori; Shimazu, Yoichiro; Yamasaki, Masatoshi; Hanayama, Yasushi

2006-01-01

A method to evaluate the moderator coefficient (MTC) and the Doppler coefficient through experimental procedures performed during reactor physics tests of PWR power plants is proposed. This method combines isothermal temperature coefficient (ITC) measurement experiments and reactor power transient experiments at low power conditions for dynamic identification. In the dynamic identification, either one of temperature coefficients can be determined in such a way that frequency response characteristics of the reactivity change observed by a digital reactivity meter is reproduced from measured data of neutron count rate and the average coolant temperature. The other unknown coefficient can also be determined by subtracting the coefficient obtained from the dynamic identification from ITC. As the proposed method can directly estimate the Doppler coefficient, the applicability of the conventional core design codes to predict the Doppler coefficient can be verified for new types of fuels such as mixed oxide fuels. The digital simulation study was carried out to show the feasibility of the proposed method. The numerical analysis showed that the MTC and the Doppler coefficient can be estimated accurately and even if there are uncertainties in the parameters of the reactor kinetics model, the accuracies of the estimated values are not seriously impaired. (author)

Nitrogen Recovery by Fe-Ti Alloy from Molten Lithium at High Temperatures

International Nuclear Information System (INIS)

Juro Yagi; Akihiro Suzuki; Takayuki Terai; Takeo Muroga

2006-01-01

Molten lithium will be used as a beam target of IFMIF (International Fusion Materials Irradiation Facility), and is also expected as a self-cooling and tritium breeding material in fusion reactors. Since tritium is generated in both cases, tritium recovery is required from viewpoints of safety and a feasible fuel cycle. Nitrogen impurity in the lithium, however, not only enhance corrosion to tubing materials, but also promote nitride contamination on a surface of yttrium, which is considered to be a tritium gettering candidate. In our previous study, nitrogen recovery by hot trap method with Fe + 5%Ti alloy as a gettering material showed a higher nitrogen reduction capacity than that with Ti or Cr metal. In this study, high temperature recovery of nitrogen with Fe-Ti alloy was examined to achieve more efficient recovery and higher recovery rate coefficient. Fe - 4%Ti alloy are fabricated by electron beam melting, and its thin plates (40 mm x 10 mm x 1 mm) are used in our experiments. The Fe - 4%Ti alloy plates were immersed into 25 g of liquid lithium in Mo crucible under Ar atmosphere. The crucible was put in a SUS316 stainless steel pot heated at 600, 700, or 800 o C up to 100 hours. A small portion of the liquid lithium in the crucible was sampled out with adequate time interval, and the nitrogen concentrations in the sampled lithium were observed by changing nitrogen to ammonia. Experiments using lithium containing about 100 wt. ppm of nitrogen at the beginning show that the nitrogen reduction became faster with temperature and the minimum achieved nitrogen concentration was less than 20 wppm in case of 800 C. SEM-EDS analysis on the plates after experiment shows a Ti-rich surface layer of tens of micrometers on the alloy immersed in lithium at 800 C, and XPS analysis indicates the surface layer is TiN, while no Ti-rich layer nor TiN were observed on the alloys immersed at 600 o C and 700 o C. By increasing temperature from 600 o C to 800 o C, the diffusion

Recovery from cannabis use disorders: Abstinence versus moderation and treatment-assisted recovery versus natural recovery.

Science.gov (United States)

Stea, Jonathan N; Yakovenko, Igor; Hodgins, David C

2015-09-01

The present study of recovery from cannabis use disorders was undertaken with 2 primary objectives that address gaps in the literature. The first objective was to provide an exploratory portrait of the recovery process from cannabis use disorders, comparing individuals who recovered naturally with those who were involved in treatment. The second objective was to explore systematically the similarities and differences between abstinence and moderation recoveries. Adults who have recovered from a cannabis use disorder were recruited in the community (N = 119). The abstinence and treatment-assisted participants exhibited higher levels of lifetime cannabis problem severity than the moderation and natural recovery participants, respectively. As well, cognitive factors were identified as the most useful strategies for recovery (e.g., thinking about benefits and negative consequences of cannabis), followed by behavioral factors (e.g., avoidance of triggers for use and high-risk situations). Findings lend further support to the effectiveness of cognitive, motivational, and behavioral strategies as helpful actions and maintenance factors involved in the recovery process. The findings also generally support the idea that cannabis use disorders lie on a continuum of problem severity, with moderation and natural recoveries more likely to occur at the lower end of the continuum and abstinence and treatment-assisted recoveries more likely to occur at the upper end. (c) 2015 APA, all rights reserved).

Research on friction coefficient of nuclear Reactor Vessel Internals Hold Down Spring: Stress coefficient test analysis method

International Nuclear Information System (INIS)

Linjun, Xie; Guohong, Xue; Ming, Zhang

2016-01-01

Graphical abstract: HDS stress coefficient test apparatus. - Highlights: • This paper performs mathematic deduction to the physical model of Hold Down Spring (HDS), establishes a mathematic model of axial load P and stress, stress coefficient and friction coefficient and designs a set of test apparatuses for simulating the pretightening process of the HDS for the first time according to a model similarity criterion. • The mathematical relation between the load and the strain is obtained about the HDS, and the mathematical model of the stress coefficient and the friction coefficient is established. So, a set of test apparatuses for obtaining the stress coefficient is designed according to the model scaling criterion and the friction coefficient of the K1000 HDS is calculated to be 0.336 through the obtained stress coefficient. • The relation curve between the theoretical load and the friction coefficient is obtained through analysis and indicates that the change of the friction coefficient f would influence the pretightening load under the condition of designed stress. The necessary pretightening load in the design process is calculated to be 5469 kN according to the obtained friction coefficient. Therefore, the friction coefficient and the pretightening load under the design conditions can provide accurate pretightening data for the analysis and design of the reactor HDS according to the operations. - Abstract: This paper performs mathematic deduction to the physical model of Hold Down Spring (HDS), establishes a mathematic model of axial load P and stress, stress coefficient and friction coefficient and designs a set of test apparatuses for simulating the pretightening process of the HDS for the first time according to a model similarity criterion. By carrying out tests and researches through a stress testing technique, P–σ curves in loading and unloading processes of the HDS are obtained and the stress coefficient k f of the HDS is obtained. So, the

Research on friction coefficient of nuclear Reactor Vessel Internals Hold Down Spring: Stress coefficient test analysis method

Energy Technology Data Exchange (ETDEWEB)

Linjun, Xie, E-mail: linjunx@zjut.edu.cn [College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310014 (China); Guohong, Xue; Ming, Zhang [Shanghai Nuclear Engineering Research & Design Institute, Shanghai 200233 (China)

2016-08-01

Graphical abstract: HDS stress coefficient test apparatus. - Highlights: • This paper performs mathematic deduction to the physical model of Hold Down Spring (HDS), establishes a mathematic model of axial load P and stress, stress coefficient and friction coefficient and designs a set of test apparatuses for simulating the pretightening process of the HDS for the first time according to a model similarity criterion. • The mathematical relation between the load and the strain is obtained about the HDS, and the mathematical model of the stress coefficient and the friction coefficient is established. So, a set of test apparatuses for obtaining the stress coefficient is designed according to the model scaling criterion and the friction coefficient of the K1000 HDS is calculated to be 0.336 through the obtained stress coefficient. • The relation curve between the theoretical load and the friction coefficient is obtained through analysis and indicates that the change of the friction coefficient f would influence the pretightening load under the condition of designed stress. The necessary pretightening load in the design process is calculated to be 5469 kN according to the obtained friction coefficient. Therefore, the friction coefficient and the pretightening load under the design conditions can provide accurate pretightening data for the analysis and design of the reactor HDS according to the operations. - Abstract: This paper performs mathematic deduction to the physical model of Hold Down Spring (HDS), establishes a mathematic model of axial load P and stress, stress coefficient and friction coefficient and designs a set of test apparatuses for simulating the pretightening process of the HDS for the first time according to a model similarity criterion. By carrying out tests and researches through a stress testing technique, P–σ curves in loading and unloading processes of the HDS are obtained and the stress coefficient k{sub f} of the HDS is obtained. So, the

Measuring of heat transfer coefficient

DEFF Research Database (Denmark)

Henningsen, Poul; Lindegren, Maria

Subtask 3.4 Measuring of heat transfer coefficient Subtask 3.4.1 Design and setting up of tests to measure heat transfer coefficient Objective: Complementary testing methods together with the relevant experimental equipment are to be designed by the two partners involved in order to measure...... the heat transfer coefficient for a wide range of interface conditions in hot and warm forging processes. Subtask 3.4.2 Measurement of heat transfer coefficient The objective of subtask 3.4.2 is to determine heat transfer values for different interface conditions reflecting those typically operating in hot...

Clustering Coefficients for Correlation Networks

Directory of Open Access Journals (Sweden)

Naoki Masuda

2018-03-01

Full Text Available Graph theory is a useful tool for deciphering structural and functional networks of the brain on various spatial and temporal scales. The clustering coefficient quantifies the abundance of connected triangles in a network and is a major descriptive statistics of networks. For example, it finds an application in the assessment of small-worldness of brain networks, which is affected by attentional and cognitive conditions, age, psychiatric disorders and so forth. However, it remains unclear how the clustering coefficient should be measured in a correlation-based network, which is among major representations of brain networks. In the present article, we propose clustering coefficients tailored to correlation matrices. The key idea is to use three-way partial correlation or partial mutual information to measure the strength of the association between the two neighboring nodes of a focal node relative to the amount of pseudo-correlation expected from indirect paths between the nodes. Our method avoids the difficulties of previous applications of clustering coefficient (and other measures in defining correlational networks, i.e., thresholding on the correlation value, discarding of negative correlation values, the pseudo-correlation problem and full partial correlation matrices whose estimation is computationally difficult. For proof of concept, we apply the proposed clustering coefficient measures to functional magnetic resonance imaging data obtained from healthy participants of various ages and compare them with conventional clustering coefficients. We show that the clustering coefficients decline with the age. The proposed clustering coefficients are more strongly correlated with age than the conventional ones are. We also show that the local variants of the proposed clustering coefficients (i.e., abundance of triangles around a focal node are useful in characterizing individual nodes. In contrast, the conventional local clustering coefficients

Clustering Coefficients for Correlation Networks.

Science.gov (United States)

Masuda, Naoki; Sakaki, Michiko; Ezaki, Takahiro; Watanabe, Takamitsu

2018-01-01

Graph theory is a useful tool for deciphering structural and functional networks of the brain on various spatial and temporal scales. The clustering coefficient quantifies the abundance of connected triangles in a network and is a major descriptive statistics of networks. For example, it finds an application in the assessment of small-worldness of brain networks, which is affected by attentional and cognitive conditions, age, psychiatric disorders and so forth. However, it remains unclear how the clustering coefficient should be measured in a correlation-based network, which is among major representations of brain networks. In the present article, we propose clustering coefficients tailored to correlation matrices. The key idea is to use three-way partial correlation or partial mutual information to measure the strength of the association between the two neighboring nodes of a focal node relative to the amount of pseudo-correlation expected from indirect paths between the nodes. Our method avoids the difficulties of previous applications of clustering coefficient (and other) measures in defining correlational networks, i.e., thresholding on the correlation value, discarding of negative correlation values, the pseudo-correlation problem and full partial correlation matrices whose estimation is computationally difficult. For proof of concept, we apply the proposed clustering coefficient measures to functional magnetic resonance imaging data obtained from healthy participants of various ages and compare them with conventional clustering coefficients. We show that the clustering coefficients decline with the age. The proposed clustering coefficients are more strongly correlated with age than the conventional ones are. We also show that the local variants of the proposed clustering coefficients (i.e., abundance of triangles around a focal node) are useful in characterizing individual nodes. In contrast, the conventional local clustering coefficients were strongly

Clustering Coefficients for Correlation Networks

Science.gov (United States)

Masuda, Naoki; Sakaki, Michiko; Ezaki, Takahiro; Watanabe, Takamitsu

2018-01-01

Graph theory is a useful tool for deciphering structural and functional networks of the brain on various spatial and temporal scales. The clustering coefficient quantifies the abundance of connected triangles in a network and is a major descriptive statistics of networks. For example, it finds an application in the assessment of small-worldness of brain networks, which is affected by attentional and cognitive conditions, age, psychiatric disorders and so forth. However, it remains unclear how the clustering coefficient should be measured in a correlation-based network, which is among major representations of brain networks. In the present article, we propose clustering coefficients tailored to correlation matrices. The key idea is to use three-way partial correlation or partial mutual information to measure the strength of the association between the two neighboring nodes of a focal node relative to the amount of pseudo-correlation expected from indirect paths between the nodes. Our method avoids the difficulties of previous applications of clustering coefficient (and other) measures in defining correlational networks, i.e., thresholding on the correlation value, discarding of negative correlation values, the pseudo-correlation problem and full partial correlation matrices whose estimation is computationally difficult. For proof of concept, we apply the proposed clustering coefficient measures to functional magnetic resonance imaging data obtained from healthy participants of various ages and compare them with conventional clustering coefficients. We show that the clustering coefficients decline with the age. The proposed clustering coefficients are more strongly correlated with age than the conventional ones are. We also show that the local variants of the proposed clustering coefficients (i.e., abundance of triangles around a focal node) are useful in characterizing individual nodes. In contrast, the conventional local clustering coefficients were strongly

From recovery values to recovery-oriented practice?

DEFF Research Database (Denmark)

Dalum, Helle; Pedersen, Inge Kryger; Cunningham, Harry

2015-01-01

Introduction: The recovery model has influenced mental health services and fostered new standards for best practice. However, knowledge about how mental health care professionals (HCPs) experience recoveryoriented programs is sparse. Aim/Question: This paper explores HCPs' experiences when...... facilitating a recovery-oriented rehabilitation program. The research question is howdo HCPs experience a change in their attitude and practicewhen applying recovery-oriented programs? Methods: This paper draws on semi-structured in-depth qualitative interviews conducted with 16 HCPs experienced...... in facilitating a recovery-oriented rehabilitation program in either the USA or Denmark. Results: Three themes emerged from the HCPs' reflections on changes in attitudes and practices: “Hopeful Attitude” captures a change in the HCPs' attitude toward a more positive view on the future for clients' living...

Form of multicomponent Fickian diffusion coefficients matrix

International Nuclear Information System (INIS)

Wambui Mutoru, J.; Firoozabadi, Abbas

2011-01-01

Highlights: → Irreversible thermodynamics establishes form of multicomponent diffusion coefficients. → Phenomenological coefficients and thermodynamic factors affect sign of diffusion coefficients. → Negative diagonal elements of diffusion coefficients matrix can occur in non-ideal mixtures. → Eigenvalues of the matrix of Fickian diffusion coefficients may not be all real. - Abstract: The form of multicomponent Fickian diffusion coefficients matrix in thermodynamically stable mixtures is established based on the form of phenomenological coefficients and thermodynamic factors. While phenomenological coefficients form a symmetric positive definite matrix, the determinant of thermodynamic factors matrix is positive. As a result, the Fickian diffusion coefficients matrix has a positive determinant, but its elements - including diagonal elements - can be negative. Comprehensive survey of reported diffusion coefficients data for ternary and quaternary mixtures, confirms that invariably the determinant of the Fickian diffusion coefficients matrix is positive.

Thermohaline loops, Stommel box models, and the Sandström theorem

OpenAIRE

Wunsch, Carl

2005-01-01

The Stommel two-box, two flow-regime box model is kinematically and dynamically equivalent to the flow in a onedimensional fluid loop, although one having awkward and extreme mixing coefficients. More generally, such a loop, when heated and cooled at the same geopotential, provides a simple example of the working of the Sandström theorem, with flow intensity capable of increasing or decreasing with growing diffusion. Stress dominates real oceanic flows, and its introduction into the purely th...

Uses and abuses of recovery: implementing recovery-oriented practices in mental health systems

Science.gov (United States)

Slade, Mike; Amering, Michaela; Farkas, Marianne; Hamilton, Bridget; O'Hagan, Mary; Panther, Graham; Perkins, Rachel; Shepherd, Geoff; Tse, Samson; Whitley, Rob

2014-01-01

An understanding of recovery as a personal and subjective experience has emerged within mental health systems. This meaning of recovery now underpins mental health policy in many countries. Developing a focus on this type of recovery will involve transformation within mental health systems. Human systems do not easily transform. In this paper, we identify seven mis-uses (“abuses”) of the concept of recovery: recovery is the latest model; recovery does not apply to “my” patients; services can make people recover through effective treatment; compulsory detention and treatment aid recovery; a recovery orientation means closing services; recovery is about making people independent and normal; and contributing to society happens only after the person is recovered. We then identify ten empirically-validated interventions which support recovery, by targeting key recovery processes of connectedness, hope, identity, meaning and empowerment (the CHIME framework). The ten interventions are peer support workers, advance directives, wellness recovery action planning, illness management and recovery, REFOCUS, strengths model, recovery colleges or recovery education programs, individual placement and support, supported housing, and mental health trialogues. Finally, three scientific challenges are identified: broadening cultural understandings of recovery, implementing organizational transformation, and promoting citizenship. PMID:24497237

Passive solar energy recovery in non-transparent facades; Passive solare Energiegewinnung im nicht-transparenten Fassadenbereich

Energy Technology Data Exchange (ETDEWEB)

Liersch, K.W. [Brandenburgische Technische Univ. Cottbus (Germany). Lehrstuhl fuer Baukonstruktion und Bauphysik

1999-10-01

Evaluation of theoretical and practical studies has shown that non-bearing glass facades of reduced transparency hold a considerable potential for energy recovery. The most important factors governing this process are solar irradiation and inhibition of reflection in the long-wave range. Net energy recovery can be expressed in terms of the decrease of the mean effective heat transmission coefficient. The achievable gains are the smaller the more effective the heat insulating properties of the wall are, i.e. the lower the U-value of the non-transparent wall is. In the case of outer walls with additional heat insulation and a heat transmission coefficient of less than k{sub w} = approx. 0.25 W/ (m-2K) energy recovery is practically negligible, with little scope for improvement through facade orientation. [Deutsch] Die Auswertung der theoretischen und messtechnischen Untersuchungen zeigt, dass mittels einer vorgehaengten, reduziert transparenten Glasfassade betraechtliche Waermegewinne zu erzielen sind. Diese ergeben sich aus der Sonnenzustrahlung sowie der Behinderung langwelliger Waermeabstrahlung. Die Gewinne lassen sich durch eine Abminderung des mittleren effektiven Waermedurchgangskoeffizienten darstellen. Die zu erzielenden Gewinne sind allerdings um so geringer, je besser die sonstige waermeschutztechnische Ausruestung der betreffenden Wand, d.h. je niedriger der k-Wert der nicht-transparenten Wandflaeche ist. Das bedeutet, dass bei Aussenwaenden mit Zusatzdaemmung und einem Waermedurchgangskoeffizienten unterhalb k{sub W}{approx}0,25 W/(m{sup 2}K) der Gewinn nicht mehr nennenswert ist, wobei dann auch die Ausrichtung der Fassade zur Himmelsrichtung das Ergebnis nur noch in geringem Umfang beeinflusst. (orig.)

Sabine absorption coefficients to random incidence absorption coefficients

DEFF Research Database (Denmark)

Jeong, Cheol-Ho

2014-01-01

into random incidence absorption coefficients for porous absorbers are investigated. Two optimization-based conversion methods are suggested: the surface impedance estimation for locally reacting absorbers and the flow resistivity estimation for extendedly reacting absorbers. The suggested conversion methods...

Measurement of off-diagonal transport coefficients in two-phase flow in porous media.

Science.gov (United States)

Ramakrishnan, T S; Goode, P A

2015-07-01

The prevalent description of low capillary number two-phase flow in porous media relies on the independence of phase transport. An extended Darcy's law with a saturation dependent effective permeability is used for each phase. The driving force for each phase is given by its pressure gradient and the body force. This diagonally dominant form neglects momentum transfer from one phase to the other. Numerical and analytical modeling in regular geometries have however shown that while this approximation is simple and acceptable in some cases, many practical problems require inclusion of momentum transfer across the interface. Its inclusion leads to a generalized form of extended Darcy's law in which both the diagonal relative permeabilities and the off-diagonal terms depend not only on saturation but also on the viscosity ratio. Analogous to application of thermodynamics to dynamical systems, any of the extended forms of Darcy's law assumes quasi-static interfaces of fluids for describing displacement problems. Despite the importance of the permeability coefficients in oil recovery, soil moisture transport, contaminant removal, etc., direct measurements to infer the magnitude of the off-diagonal coefficients have been lacking. The published data based on cocurrent and countercurrent displacement experiments are necessarily indirect. In this paper, we propose a null experiment to measure the off-diagonal term directly. For a given non-wetting phase pressure-gradient, the null method is based on measuring a counter pressure drop in the wetting phase required to maintain a zero flux. The ratio of the off-diagonal coefficient to the wetting phase diagonal coefficient (relative permeability) may then be determined. The apparatus is described in detail, along with the results obtained. We demonstrate the validity of the experimental results and conclude the paper by comparing experimental data to numerical simulation. Copyright © 2015 Elsevier Inc. All rights reserved.

Low degree Earth's gravity coefficients determined from different space geodetic observations and climate models

Science.gov (United States)

Wińska, Małgorzata; Nastula, Jolanta

2017-04-01

Large scale mass redistribution and its transport within the Earth system causes changes in the Earth's rotation in space, gravity field and Earth's ellipsoid shape. These changes are observed in the ΔC21, ΔS21, and ΔC20 spherical harmonics gravity coefficients, which are proportional to the mass load-induced Earth rotational excitations. In this study, linear trend, decadal, inter-annual, and seasonal variations of low degree spherical harmonics coefficients of Earth's gravity field, determined from different space geodetic techniques, Gravity Recovery and Climate Experiment (GRACE), satellite laser ranging (SLR), Global Navigation Satellite System (GNSS), Earth rotation, and climate models, are examined. In this way, the contribution of each measurement technique to interpreting the low degree surface mass density of the Earth is shown. Especially, we evaluate an usefulness of several climate models from the Coupled Model Intercomparison Project phase 5 (CMIP5) to determine the low degree Earth's gravity coefficients using GRACE satellite observations. To do that, Terrestrial Water Storage (TWS) changes from several CMIP5 climate models are determined and then these simulated data are compared with the GRACE observations. Spherical harmonics ΔC21, ΔS21, and ΔC20 changes are calculated as the sum of atmosphere and ocean mass effect (GAC values) taken from GRACE and a land surface hydrological estimate from the selected CMIP5 climate models. Low degree Stokes coefficients of the surface mass density determined from GRACE, SLR, GNSS, Earth rotation measurements and climate models are compared to each other in order to assess their consistency. The comparison is done by using different types of statistical and signal processing methods.

Transport Coefficients of Fluids

CERN Document Server

Eu, Byung Chan

2006-01-01

Until recently the formal statistical mechanical approach offered no practicable method for computing the transport coefficients of liquids, and so most practitioners had to resort to empirical fitting formulas. This has now changed, as demonstrated in this innovative monograph. The author presents and applies new methods based on statistical mechanics for calculating the transport coefficients of simple and complex liquids over wide ranges of density and temperature. These molecular theories enable the transport coefficients to be calculated in terms of equilibrium thermodynamic properties, and the results are shown to account satisfactorily for experimental observations, including even the non-Newtonian behavior of fluids far from equilibrium.

Use of satellite gravimetry for estimating recent solid Earth changes

Science.gov (United States)

Ramillien, Guillaume

2014-05-01

Since its launch in March 2002, the Gravity Recovery & Climate Experiment (GRACE) satellite mission provides a global mapping of the time variations of the Earth's gravity field for the recent period. Official centers such as Center of Space Research (CSR) in Austin, TX, Jet Propulsion Laboratory (JPL) in Pasadena, CA and GeoForschungZentrum (GFZ) in Potsdam, Germany, provide 10-day and monthly solutions of Stokes coefficients (i.e., spherical harmonic coefficients of the geopotential) up to harmonic degree 50-60 (or, equivalently, a spatial resolution of 300-400 km) for the timespan 2002-2012. Tiny variations of the gravity measured by GRACE are mainly due to the total water storage change on continents. Therefore, these solutions of water mass can be used to correct other datasets, and then isolate the gravity signatures of large and sudden earthquakes, as well as of the continuous Post Glacial Rebound (PGR) rate. As these measured seasonal variations of continental hydrology represent the variations of water mass load, it is also possible to derive the deformation of the terrestrial surface associated to this varying load using Love numbers. These latter numbers are obtained by assuming an elastic Earth model. In the center of the Amazon basin, the seasonal displacements of the surface due to hydrology reach amplitudes of a few centimeters typically. Time-series of GRACE-based radial displacement of the surface can be analysed and compared with independent local GPS records for validation.

Energy coefficients for a propeller series

DEFF Research Database (Denmark)

Olsen, Anders Smærup

2004-01-01

The efficiency for a propeller is calculated by energy coefficients. These coefficients are related to four types of losses, i.e. the axial, the rotational, the frictional, and the finite blade number loss, and one gain, i.e. the axial gain. The energy coefficients are derived by use...... of the potential theory with the propeller modelled as an actuator disk. The efficiency based on the energy coefficients is calculated for a propeller series. The results show a good agreement between the efficiency based on the energy coefficients and the efficiency obtained by a vortex-lattice method....

Analysis of potassium nitrate purification with recovery of solvent through single effect mechanical vapor compression

Directory of Open Access Journals (Sweden)

Kiprotich E. Kosgey

2017-12-01

Full Text Available Analysis of purification of potassium nitrate with incorporation of single effect mechanical vapor compressor for solvent recovery was done. Analysis focused on the effect of concentration and temperature of mother liquor on the energy efficiency of the process and the amount of recovered solvent. Performance coefficient of mechanical vapor compressor ranged between 1.5 and 7.5 depending primarily on the temperature of mother liquor. It was found that with increase in temperature of mother liquor through pre-heating, the power of the compressor, compression ratio and amount of heat supplied to the evaporator decrease. For a 40% concentrated feed solution and mother liquor temperature above 80 °C, performance coefficient is higher than 4. It is therefore concluded that preheating mother liquor and reduction of the effect of concentration of both mother liquor and concentrated waste stream through other methods reduces the power consumption of purification process. Keywords: Performance coefficient, Mother liquor, Concentrated solution, Recovered solvent, Boiling point elevation, Mechanical vapor compressor

A drying coefficient for building materials

DEFF Research Database (Denmark)

Scheffler, Gregor Albrecht; Plagge, Rudolf

2009-01-01

coefficient is defined which can be determined based on measured drying data. The correlation of this coefficient with the water absorption and the vapour diffusion coefficient is analyzed and its additional information content is critically challenged. As result, a drying coefficient has been derived......The drying experiment is an important element of the hygrothermal characterisation of building materials. Contrary to other moisture transport experiments as the vapour diffusion and the water absorption test, it is until now not possible to derive a simple coefficient for the drying. However......, in many cases such a coefficient would be highly appreciated, e.g. in interaction of industry and research or for the distinction and selection of suitable building materials throughout design and practise. This article first highlights the importance of drying experiments for hygrothermal...

Absorption and recovery of n-hexane in aqueous solutions of fluorocarbon surfactants.

Science.gov (United States)

Xiao, Xiao; Yan, Bo; Fu, Jiamo; Xiao, Xianming

2015-11-01

n-Hexane is widely used in industrial production as an organic solvent. As an industrial exhaust gas, the contribution of n-hexane to air pollution and damage to human health are attracting increasing attention. In the present study, aqueous solutions of two fluorocarbon surfactants (FSN100 and FSO100) were investigated for their properties of solubilization and dynamic absorption of n-hexane, as well as their capacity for regeneration and n-hexane recovery by thermal distillation. The results show that the two fluorocarbon surfactants enhance dissolution and absorption of n-hexane, and their effectiveness is closely related to their concentrations in solution. For low concentration solutions (0.01%-0.30%), the partition coefficient decreases dramatically and the saturation capacity increases significantly with increasing concentration, but the changes for both are more modest when the concentration is over 0.30%. The FSO100 solution presents a smaller partition coefficient and a greater saturation capacity than the FSN100 solution at the same concentration, indicating a stronger solubilization for n-hexane. Thermal distillation is a feasible method to recover n-hexane from these absorption solutions, and to regenerate them. With 90sec heating at 80-85°C, the recovery of n-hexane ranges between 81% and 85%, and the regenerated absorption solution maintains its original performance during reuse. This study provides basic information on two fluorocarbon surfactants for application in the treatment of industrial n-hexane waste gases. Copyright © 2015. Published by Elsevier B.V.

Recovery of the Aharonov-Bohm oscillations in asymmetrical quantum rings

Energy Technology Data Exchange (ETDEWEB)

Voskoboynikov, O., E-mail: vam@faculty.nctu.edu.tw [Department of Electronics Engineering, National Chiao Tung University, Hsinchu, Taiwan (China)

2016-07-15

We theoretically investigate suppression and recovery of the Aharonov-Bohm oscillations of the diamagnetic response of electrons (holes) confined in self-assembled In{sub c}Ga{sub 1−c}As/GaAs semiconductor reflection asymmetrical quantum rings. Based on the mapping method and gauge-origin-independent definition for the magnetic vector potential we simulate the energies and wave functions of the electron (hole) under external magnetic and electric fields. We examine the transformation of the ground state wave function of the electron (hole) in reflection asymmetrical rings from localized in one of the potential valleys (dotlike shape of the wave function) to distributed over all volume of the ring (ringlike shape) under an appropriate lateral electric field. This transformation greatly recovers the electron (hole) diamagnetic coefficient and Aharonov-Bohm oscillations of the diamagnetic response of the ring. However, the recovering electric field for the first Aharonov-Bohm diamagnetic oscillation of the electron is a suppressing one for the hole (and vice versa). This can block the recovery of the optical Aharonow-Bohm effect in In{sub c}Ga{sub 1−c}As/GaAs asymmetrically wobbled rings. However, the recovery of the Aharonov-Bohm oscillations for the independent electron (hole) by the external electric field remains interesting and feasible objective for the asymmetric rings.

Quadrature formulas for Fourier coefficients

KAUST Repository

Bojanov, Borislav

2009-09-01

We consider quadrature formulas of high degree of precision for the computation of the Fourier coefficients in expansions of functions with respect to a system of orthogonal polynomials. In particular, we show the uniqueness of a multiple node formula for the Fourier-Tchebycheff coefficients given by Micchelli and Sharma and construct new Gaussian formulas for the Fourier coefficients of a function, based on the values of the function and its derivatives. © 2009 Elsevier B.V. All rights reserved.

Recent Applications of Fluorescence Recovery after Photobleaching (FRAP) to Membrane Bio-Macromolecules

Science.gov (United States)

Rayan, Gamal; Guet, Jean-Erik; Taulier, Nicolas; Pincet, Frederic; Urbach, Wladimir

2010-01-01

This review examines some recent applications of fluorescence recovery after photobleaching (FRAP) to biopolymers, while mainly focusing on membrane protein studies. Initially, we discuss the lateral diffusion of membrane proteins, as measured by FRAP. Then, we talk about the use of FRAP to probe interactions between membrane proteins by obtaining fundamental information such as geometry and stoichiometry of the interacting complex. Afterwards, we discuss some applications of FRAP at the cellular level as well as the level of organisms. We conclude by comparing diffusion coefficients obtained by FRAP and several other alternative methods. PMID:22219695

Reproducibility of The Random Incidence Absorption Coefficient Converted From the Sabine Absorption Coefficient

DEFF Research Database (Denmark)

Jeong, Cheol-Ho; Chang, Ji-ho

2015-01-01

largely depending on the test room. Several conversion methods for porous absorbers from the Sabine absorption coefficient to the random incidence absorption coefficient were suggested by considering the finite size of a test specimen and non-uniformly incident energy onto the specimen, which turned out...... resistivity optimization outperforms the surface impedance optimization in terms of the reproducibility....

Uncovering Recovery: The Resistible Rise of Recovery and Resilience

Directory of Open Access Journals (Sweden)

David Harper

2012-10-01

Full Text Available Discourses of recovery and resilience have risen to positions of dominance in the mental health field. Models of recovery and resilience enjoy purchase, in both policy and practice, across a range of settings from self-described psychiatric survivors through to mental health charities through to statutory mental health service providers. Despite this ubiquity, there is confusion about what recovery means. In this article we problematize notions of recovery and resilience, and consider what, if anything, should be recovered from these concepts. We focus on three key issues, i individualization, ii the persistence of a deficit model, and iii collective approaches to recovery. Through documentary analysis we consider these issues across third sector organizations, and public and mental health policy. Firstly, definitional debates about recovery reflect wider ideological debates about the nature of mental health. The vagueness of these concepts and implicit assumptions inherent in dominant recovery and resilience discourses render them problematic because they individualize what are social problems. Secondly, these discourses, despite being seen as inherently liberatory are conceptually dependent on a notion of deficit in that talk of “positives” and “strengths” requires the existence of “negatives” and “weaknesses” for these concepts to make sense.  We argue that this does little to substantially transform dominant understandings of psychological distress. Thirdly, these issues combine to impact upon the progressive potential of recovery. It comes to be seen as an individualistic experiential narrative accompaniment to medical understandings where the structural causes of distress are obscured. This in turn impacts upon the potential for recovery to be used to explore more collective, political aspects of emotional distress. Drawing on the work of Fraser, we use this critique to characterize “recovery” as a “struggle for

Building addiction recovery capital through online participation in a recovery community.

Science.gov (United States)

Bliuc, Ana-Maria; Best, David; Iqbal, Muhammad; Upton, Katie

2017-11-01

This study examines how online participation in a community of recovery contributes to personal journeys of recovery. It investigates whether recovery capital building - as indicated by increased levels and quality of online social interactions - and markers of positive identity development predict retention in a recovery program designed around fostering community involvement for early stage recovery addicts. It was predicted that online participation on the group's Facebook page and positive identity development are associated to retention in the program. To map how participants interact online, social network analysis (SNA) based on naturally occurring online data (N = 609) on the Facebook page of a recovery community was conducted. Computerised linguistic analyses evaluated sentiment of the textual data (capturing social identity markers). Linear regression analyses evaluated whether indicators of recovery capital predict program retention. To illustrate the findings in the context of the specific recovery community, presented are two case studies of key participants who moved from the periphery to the centre of the social network. By conducting in-depth interviews with these participants, personal experiences of engagement in the online community of group members who have undergone the most significant changes since joining the community are explored. Retention in the program was determined by a) the number of comment 'likes' and all 'likes' received on the Facebook page; b) position in the social network (degree of centrality); and c) linguistic content around group identity and achievement. Positive online interactions between members of recovery communities support the recovery process through helping participants to develop recovery capital that binds them to groups supportive of positive change. Copyright © 2017 Elsevier Ltd. All rights reserved.

Drag Coefficient Estimation in Orbit Determination

Science.gov (United States)

McLaughlin, Craig A.; Manee, Steve; Lichtenberg, Travis

2011-07-01

Drag modeling is the greatest uncertainty in the dynamics of low Earth satellite orbits where ballistic coefficient and density errors dominate drag errors. This paper examines fitted drag coefficients found as part of a precision orbit determination process for Stella, Starlette, and the GEOSAT Follow-On satellites from 2000 to 2005. The drag coefficients for the spherical Stella and Starlette satellites are assumed to be highly correlated with density model error. The results using MSIS-86, NRLMSISE-00, and NRLMSISE-00 with dynamic calibration of the atmosphere (DCA) density corrections are compared. The DCA corrections were formulated for altitudes of 200-600 km and are found to be inappropriate when applied at 800 km. The yearly mean fitted drag coefficients are calculated for each satellite for each year studied. The yearly mean drag coefficients are higher for Starlette than Stella, where Starlette is at a higher altitude. The yearly mean fitted drag coefficients for all three satellites decrease as solar activity decreases after solar maximum.

Dynamics analysis of SIR epidemic model with correlation coefficients and clustering coefficient in networks.

Science.gov (United States)

Zhang, Juping; Yang, Chan; Jin, Zhen; Li, Jia

2018-07-14

In this paper, the correlation coefficients between nodes in states are used as dynamic variables, and we construct SIR epidemic dynamic models with correlation coefficients by using the pair approximation method in static networks and dynamic networks, respectively. Considering the clustering coefficient of the network, we analytically investigate the existence and the local asymptotic stability of each equilibrium of these models and derive threshold values for the prevalence of diseases. Additionally, we obtain two equivalent epidemic thresholds in dynamic networks, which are compared with the results of the mean field equations. Copyright © 2018 Elsevier Ltd. All rights reserved.

Standards for Standardized Logistic Regression Coefficients

Science.gov (United States)

Menard, Scott

2011-01-01

Standardized coefficients in logistic regression analysis have the same utility as standardized coefficients in linear regression analysis. Although there has been no consensus on the best way to construct standardized logistic regression coefficients, there is now sufficient evidence to suggest a single best approach to the construction of a…

Variation in aerodynamic coefficients with altitude

Science.gov (United States)

Shahid, Faiza; Hussain, Mukkarum; Baig, Mirza Mehmood; Haq, Ihtram ul

Precise aerodynamics performance prediction plays key role for a flying vehicle to get its mission completed within desired accuracy. Aerodynamic coefficients for same Mach number can be different at different altitude due to difference in Reynolds number. Prediction of these aerodynamics coefficients can be made through experiments, analytical solution or Computational Fluid Dynamics (CFD). Advancements in computational power have generated the concept of using CFD as a virtual Wind Tunnel (WT), hence aerodynamic performance prediction in present study is based upon CFD (numerical test rig). Simulations at different altitudes for a range of Mach numbers with zero angle of attack are performed to predict axial force coefficient behavior with altitude (Reynolds number). Similar simulations for a fixed Mach number '3' and a range of angle of attacks are also carried out to envisage the variation in normal force and pitching moment coefficients with altitude (Reynolds number). Results clearly depict that the axial force coefficient is a function of altitude (Reynolds number) and increase as altitude increases, especially for subsonic region. Variation in axial force coefficient with altitude (Reynolds number) slightly increases for larger values of angle of attacks. Normal force and pitching moment coefficients do not depend on altitude (Reynolds number) at smaller values of angle of attacks but show slight decrease as altitude increases. Present study suggests that variation of normal force and pitching moment coefficients with altitude can be neglected but the variation of axial force coefficient with altitude should be considered for vehicle fly in dense atmosphere. It is recommended to continue this study to more complex configurations for various Mach numbers with side slip and real gas effects.

Implications of NGA for NEHRP site coefficients

Science.gov (United States)

Borcherdt, Roger D.

2012-01-01

Three proposals are provided to update tables 11.4-1 and 11.4-2 of Minimum Design Loads for Buildings and Other Structures (7-10), by the American Society of Civil Engineers (2010) (ASCE/SEI 7-10), with site coefficients implied directly by NGA (Next Generation Attenuation) ground motion prediction equations (GMPEs). Proposals include a recommendation to use straight-line interpolation to infer site coefficients at intermediate values of ̅vs (average shear velocity). Site coefficients are recommended to ensure consistency with ASCE/SEI 7-10 MCER (Maximum Considered Earthquake) seismic-design maps and simplified site-specific design spectra procedures requiring site classes with associated tabulated site coefficients and a reference site class with unity site coefficients. Recommended site coefficients are confirmed by independent observations of average site amplification coefficients inferred with respect to an average ground condition consistent with that used for the MCER maps. The NGA coefficients recommended for consideration are implied directly by the NGA GMPEs and do not require introduction of additional models.

From recovery to regulation: an attempt to reconceptualize 'recovery from work'.

Science.gov (United States)

Zijlstra, F R H; Cropley, M; Rydstedt, L W

2014-08-01

The concept of 'recovery' (from work) has quickly gained in importance in the occupational health literature. However, we think that the conceptualization of 'recovery' needs some more attention. Although many authors acknowledge that 'recovery' refers to a 'process', the concept is often treated as a static construct. In this paper, we argue that recovery should be conceptualized as a dynamic construct related to changes in psychophysiological state of the person. We refer to two main theories that have provided a theoretical framework for research in this area: Meijman & Mulder's Effort-Recovery (E-R) model and Hobfoll's Conservation of Resources theory. In particular, the E-R model has been seminal in this area and stresses the element of changing psychophysiological states that has been used for reconceptualising 'recovery'. Various biological rhythms influence these changing psychophysiological states, and thus the level of energy (or effort) a person can mobilize or wants to mobilize. A distinction is made between 'physical fatigue' and 'mental fatigue' and its consequences for recovery. The discrepancy between 'actual state' and 'required state' has been suggested as the basis for 'recovery'. This emphasises that recovery is a dynamic and ongoing process, which also included motivational aspects, in particular as far as mental work is concerned. The capacity to maintain self-regulation of one's psychophysiological state is important in this respect. Thus, we propose that 'recovery' is the continuous process of harmonizing the 'actual state' with the state that is 'required' at that moment. Copyright © 2014 John Wiley & Sons, Ltd.

Correlates of justice encounter in service recovery and word-of-mouth publicity

Directory of Open Access Journals (Sweden)

Hart O. Awa

2016-12-01

Full Text Available This paper examines word-of-mouth publicity as an outcome of consumer perception of equitable recovery programs. Survey data were drawn from 317 teachers of Federal Government Colleges and 79 executives of mobile telephone firms in the southeastern and south–south zones; this sample came from locations where Global Systems for Mobile Communications and Code Data Multiple Access networks have interface. Using the partial least square to analyze the data, the path coefficients with their respective t-values greater than 1.96 confirm that the justice dimensions have statistically significant relationship with word-of-mouth. Thus, the manipulation of justice dimensions in the events of service failure affects customers’ advocacy behavior. The study recommends proactive and relational approaches in dealing with customer issues as well as fair and equitable recovery and complaint handling programs to suit the needs of the complainants, get them satisfied, and to cause them to progress in the loyalty ladder.

Probabilistic optimization of safety coefficients

International Nuclear Information System (INIS)

Marques, M.; Devictor, N.; Magistris, F. de

1999-01-01

This article describes a reliability-based method for the optimization of safety coefficients defined and used in design codes. The purpose of the optimization is to determine the partial safety coefficients which minimize an objective function for sets of components and loading situations covered by a design rule. This objective function is a sum of distances between the reliability of the components designed using the safety coefficients and a target reliability. The advantage of this method is shown on the examples of the reactor vessel, a vapour pipe and the safety injection circuit. (authors)

Estimation of the simple correlation coefficient.

Science.gov (United States)

Shieh, Gwowen

2010-11-01

This article investigates some unfamiliar properties of the Pearson product-moment correlation coefficient for the estimation of simple correlation coefficient. Although Pearson's r is biased, except for limited situations, and the minimum variance unbiased estimator has been proposed in the literature, researchers routinely employ the sample correlation coefficient in their practical applications, because of its simplicity and popularity. In order to support such practice, this study examines the mean squared errors of r and several prominent formulas. The results reveal specific situations in which the sample correlation coefficient performs better than the unbiased and nearly unbiased estimators, facilitating recommendation of r as an effect size index for the strength of linear association between two variables. In addition, related issues of estimating the squared simple correlation coefficient are also considered.

Determination of adenine based on the fluorescence recovery of the L-Tryptophan-Cu(2+) complex.

Science.gov (United States)

Duan, Ruilin; Li, Chunyan; Liu, Shaopu; Liu, Zhongfang; Li, Yuanfang; Yuan, Yusheng; Hu, Xiaoli

2016-01-05

A simple and sensitive method for determination of adenine was developed based on fluorescence quenching and recovery of L-Tryptophan (L-Trp). The fluorescence of L-Trp could efficiently quenched by copper ion compared with other common metal ions. Upon addition of adenine (Ade) in L-Trp-Cu(II) system, the fluorescence was reoccurred. Under the optimum conditions, the recovery fluorescence intensity was linearly correlated with the concentration of adenine in the range from 0.34 to 25.0μmolL(-1), with a correlation coefficient (R(2)) of 0.9994. The detection limit (3σ/k) was 0.046μmolL(-1), indicating that this method could applied to detect trace adenine. In this study, amino acids including L-Trp, D-Trp, L-Tyr, D-Tyr, L-Phe, D-Phe were investigated and only L-Trp could well chelated copper ion. Additionally, the mechanism of quench and recovery also were discussed and the method was successfully applied to detect the adenine in DNA with satisfactory results. Copyright © 2015 Elsevier B.V. All rights reserved.

Variation in aerodynamic coefficients with altitude

Directory of Open Access Journals (Sweden)

Faiza Shahid

Full Text Available Precise aerodynamics performance prediction plays key role for a flying vehicle to get its mission completed within desired accuracy. Aerodynamic coefficients for same Mach number can be different at different altitude due to difference in Reynolds number. Prediction of these aerodynamics coefficients can be made through experiments, analytical solution or Computational Fluid Dynamics (CFD. Advancements in computational power have generated the concept of using CFD as a virtual Wind Tunnel (WT, hence aerodynamic performance prediction in present study is based upon CFD (numerical test rig. Simulations at different altitudes for a range of Mach numbers with zero angle of attack are performed to predict axial force coefficient behavior with altitude (Reynolds number. Similar simulations for a fixed Mach number ‘3’ and a range of angle of attacks are also carried out to envisage the variation in normal force and pitching moment coefficients with altitude (Reynolds number. Results clearly depict that the axial force coefficient is a function of altitude (Reynolds number and increase as altitude increases, especially for subsonic region. Variation in axial force coefficient with altitude (Reynolds number slightly increases for larger values of angle of attacks. Normal force and pitching moment coefficients do not depend on altitude (Reynolds number at smaller values of angle of attacks but show slight decrease as altitude increases. Present study suggests that variation of normal force and pitching moment coefficients with altitude can be neglected but the variation of axial force coefficient with altitude should be considered for vehicle fly in dense atmosphere. It is recommended to continue this study to more complex configurations for various Mach numbers with side slip and real gas effects. Keywords: Mach number, Reynolds number, Blunt body, Altitude effect, Angle of attacks

Anomalous Seebeck coefficient in boron carbides

International Nuclear Information System (INIS)

Aselage, T.L.; Emin, D.; Wood, C.; Mackinnon, I.D.R.; Howard, I.A.

1987-01-01

Boron carbides exhibit an anomalously large Seebeck coefficient with a temperature coefficient that is characteristic of polaronic hopping between inequivalent sites. The inequivalence in the sites is associated with disorder in the solid. The temperature dependence of the Seebeck coefficient for materials prepared by different techniques provides insight into the nature of the disorder

Gini coefficient as a life table function

Directory of Open Access Journals (Sweden)

2003-06-01

Full Text Available This paper presents a toolkit for measuring and analyzing inter-individual inequality in length of life by Gini coefficient. Gini coefficient and four other inequality measures are defined on the length-of-life distribution. Properties of these measures and their empirical testing on mortality data suggest a possibility for different judgements about the direction of changes in the degree of inequality by using different measures. A new computational procedure for the estimation of Gini coefficient from life tables is developed and tested on about four hundred real life tables. The estimates of Gini coefficient are precise enough even for abridged life tables with the final age group of 85+. New formulae have been developed for the decomposition of differences between Gini coefficients by age and cause of death. A new method for decomposition of age-components into effects of mortality and composition of population by group is developed. Temporal changes in the effects of elimination of causes of death on Gini coefficient are analyzed. Numerous empirical examples show: Lorenz curves for Sweden, Russia and Bangladesh in 1995, proportional changes in Gini coefficient and four other measures of inequality for the USA in 1950-1995 and for Russia in 1959-2000. Further shown are errors of estimates of Gini coefficient when computed from various types of mortality data of France, Japan, Sweden and the USA in 1900-95, decompositions of the USA-UK difference in life expectancies and Gini coefficients by age and cause of death in 1997. As well, effects of elimination of major causes of death in the UK in 1951-96 on Gini coefficient, age-specific effects of mortality and educational composition of the Russian population on changes in life expectancy and Gini coefficient between 1979 and 1989. Illustrated as well are variations in life expectancy and Gini coefficient across 32 countries in 1996-1999 and associated changes in life expectancy and Gini

Determination of the surface drag coefficient

DEFF Research Database (Denmark)

Mahrt, L.; Vickers, D.; Sun, J.L.

2001-01-01

This study examines the dependence of the surface drag coefficient on stability, wind speed, mesoscale modulation of the turbulent flux and method of calculation of the drag coefficient. Data sets over grassland, sparse grass, heather and two forest sites are analyzed. For significantly unstable...... conditions, the drag coefficient does not depend systematically on z/L but decreases with wind speed for fixed intervals of z/L, where L is the Obukhov length. Even though the drag coefficient for weak wind conditions is sensitive to the exact method of calculation and choice of averaging time, the decrease...... of the drag coefficient with wind speed occurs for all of the calculation methods. A classification of flux calculation methods is constructed, which unifies the most common previous approaches. The roughness length corresponding to the usual Monin-Obukhov stability functions decreases with increasing wind...

Study of recovery and stability of derivatized gliphosate and AMPA in soil using national resins

OpenAIRE

Souza, Tomaz Alves de; Matta, Marcia Helena de Rizzo da; Montagner, Émerson; Abreu, Adley Bergson Gonçalves de

2006-01-01

In the present paper we studied the recoveries of glyphosate, N-(phosphonomethyl)glycine (GLY) and its major metabolite, (aminomethyl)phosphonic acid (AMPA) in soil using national (Brazilian) ion-exchange resins, derivatization by a mixture of trifluoroacetic anhydride and trifluoroethanol and analyses by GC-MS. The quantification limits were 12 ng.g-1 for both compounds and the methodology showed a range of recuperation from 85 to 94% with coefficients of variation (CV) ranging from 4.07 to ...

Improving sample recovery

International Nuclear Information System (INIS)

Blanchard, R.J.

1995-09-01

This Engineering Task Plan (ETP) describes the tasks, i.e., tests, studies, external support and modifications planned to increase the recovery of the recovery of the waste tank contents using combinations of improved techniques, equipment, knowledge, experience and testing to better the recovery rates presently being experienced

Study of transport coefficients of nanodiamond nanofluids

Science.gov (United States)

Pryazhnikov, M. I.; Minakov, A. V.; Guzei, D. V.

2017-09-01

Experimental data on the thermal conductivity coefficient and viscosity coefficient of nanodiamond nanofluids are presented. Distilled water and ethylene glycol were used as the base fluid. Dependences of transport coefficients on concentration are obtained. It was shown that the thermal conductivity coefficient increases with increasing nanodiamonds concentration. It was shown that base fluids properties and nanodiamonds concentration affect on the rheology of nanofluids.

An investigation on groundwater recovery rate within sub sea floor tunnels at closed coal mines

International Nuclear Information System (INIS)

Nakata, Eiji; Suenaga, Hiroshi; Oyama, Takahiro; Nomura, Tokisada; Ichihara, Yoshihisa

2008-01-01

The groundwater recovery rate investigated at the closed coal mines extended within sub sea floor tunnels. The Ikeshima and the Taiheiyo coal mine companies exploited the deep coal-bearing strata beneath the ocean. Ikeshima coal mine, excavated S.L. -650m to 6km offshore from Ikeshima island, was closed at November 2002, and Taiheiyo coal mine, excavated S.L. -720m to 9km offshore from Hokkaido, was stopped to excavate from the deep area at January 2003. After closing and stopping of development, we began the investigation of the groundwater recovery rate at both coal mines. The groundwater level of Ikeshima coal mine raised +405m per 1.8 years at the main shaft. The permeability coefficient estimated between 10 - 8 m /s and 10 -6 m/s to use the water recovery rate at the shaft. Otherwise, at Taiheiyo coal mine, we measured the air pressure in tubes used by 3.5km 2.5km, and 1.5km length 2mm diameters tubes to estimate the groundwater recovery level at the 3.2km offshore plug site. Groundwater didn't reach 4.7km (1.5+3.2km) area until November 2004. There were breakdown of shotcleate and rock mass from the roof of tunnel at 5.3km from offshore line. In this paper, we try to show the groundwater recovery rate of these sub sea floor collieries. (author)

Feasibility of Diffusion Tensor Imaging for Assessing Functional Recovery in Rats with Olfactory Ensheathing Cell Transplantation After Contusive Spinal Cord Injury (SCI).

Science.gov (United States)

Gu, Mengchao; Gao, Zhengchao; Li, Xiaohui; Zhao, Feng; Guo, Lei; Liu, Jiantao; He, Xijing

2017-06-17

BACKGROUND Olfactory ensheathing cell transplantation is a promising treatment for spinal cord injury. Diffusion tensor imaging has been applied to assess various kinds of spinal cord injury. However, it has rarely been used to evaluate the beneficial effects of olfactory ensheathing cell transplantation. This study aimed to explore the feasibility of diffusion tensor imaging in the evaluation of functional recovery in rats with olfactory ensheathing cell transplantation after contusive spinal cord injury. MATERIAL AND METHODS Immunofluorescence staining was performed to determine the purity of olfactory ensheathing cells. Rats received cell transplantation at week 1 after injury. Basso, Beattie, and Bresnahan score was used to assess the functional recovery. Magnetic resonance imaging was applied weekly, including diffusion tensor imaging. Diffusion tensor tractography was reconstructed to visualize the repair process. RESULTS The results showed that olfactory ensheathing cell transplantation increased the functional and histological recovery and restrained the secondary injury process after the initial spinal cord injury. The fractional anisotropy values in rats with cell transplantation were significantly higher than those in the control group, while the apparent diffusion coefficient values were significantly lower. Basso, Beattie, and Bresnahan score was positively and linearly correlated with fractional anisotropy value, and it was negatively and linearly correlated with apparent diffusion coefficient value. CONCLUSIONS These findings suggest that diffusion tensor imaging parameters are sensitive biomarker indices for olfactory ensheathing cell transplantation interventions, and diffusion tensor imaging scan can reflect the functional recovery promoted by the olfactory ensheathing cell transplantation after contusive spinal cord injury.

Meta-Analysis of Coefficient Alpha

Science.gov (United States)

Rodriguez, Michael C.; Maeda, Yukiko

2006-01-01

The meta-analysis of coefficient alpha across many studies is becoming more common in psychology by a methodology labeled reliability generalization. Existing reliability generalization studies have not used the sampling distribution of coefficient alpha for precision weighting and other common meta-analytic procedures. A framework is provided for…

Rapid Recovery Gene Downregulation during Excess-Light Stress and Recovery in Arabidopsis.

Science.gov (United States)

Crisp, Peter A; Ganguly, Diep R; Smith, Aaron B; Murray, Kevin D; Estavillo, Gonzalo M; Searle, Iain; Ford, Ethan; Bogdanović, Ozren; Lister, Ryan; Borevitz, Justin O; Eichten, Steven R; Pogson, Barry J

2017-08-01

Stress recovery may prove to be a promising approach to increase plant performance and, theoretically, mRNA instability may facilitate faster recovery. Transcriptome (RNA-seq, qPCR, sRNA-seq, and PARE) and methylome profiling during repeated excess-light stress and recovery was performed at intervals as short as 3 min. We demonstrate that 87% of the stress-upregulated mRNAs analyzed exhibit very rapid recovery. For instance, HSP101 abundance declined 2-fold every 5.1 min. We term this phenomenon rapid recovery gene downregulation (RRGD), whereby mRNA abundance rapidly decreases promoting transcriptome resetting. Decay constants ( k ) were modeled using two strategies, linear and nonlinear least squares regressions, with the latter accounting for both transcription and degradation. This revealed extremely short half-lives ranging from 2.7 to 60.0 min for 222 genes. Ribosome footprinting using degradome data demonstrated RRGD loci undergo cotranslational decay and identified changes in the ribosome stalling index during stress and recovery. However, small RNAs and 5'-3' RNA decay were not essential for recovery of the transcripts examined, nor were any of the six excess light-associated methylome changes. We observed recovery-specific gene expression networks upon return to favorable conditions and six transcriptional memory types. In summary, rapid transcriptome resetting is reported in the context of active recovery and cellular memory. © 2017 American Society of Plant Biologists. All rights reserved.

Analysis of internal conversion coefficients

International Nuclear Information System (INIS)

Coursol, N.; Gorozhankin, V.M.; Yakushev, E.A.; Briancon, C.; Vylov, Ts.

2000-01-01

An extensive database has been assembled that contains the three most widely used sets of calculated internal conversion coefficients (ICC): [Hager R.S., Seltzer E.C., 1968. Internal conversion tables. K-, L-, M-shell Conversion coefficients for Z=30 to Z=103, Nucl. Data Tables A4, 1-237; Band I.M., Trzhaskovskaya M.B., 1978. Tables of gamma-ray internal conversion coefficients for the K-, L- and M-shells, 10≤Z≤104, Special Report of Leningrad Nuclear Physics Institute; Roesel F., Fries H.M., Alder K., Pauli H.C., 1978. Internal conversion coefficients for all atomic shells, At. Data Nucl. Data Tables 21, 91-289] and also includes new Dirac-Fock calculations [Band I.M. and Trzhaskovskaya M.B., 1993. Internal conversion coefficients for low-energy nuclear transitions, At. Data Nucl. Data Tables 55, 43-61]. This database is linked to a computer program to plot ICCs and their combinations (sums and ratios) as a function of Z and energy, as well as relative deviations of ICC or their combinations for any pair of tabulated data. Examples of these analyses are presented for the K-shell and total ICCs of the gamma-ray standards [Hansen H.H., 1985. Evaluation of K-shell and total internal conversion coefficients for some selected nuclear transitions, Eur. Appl. Res. Rept. Nucl. Sci. Tech. 11.6 (4) 777-816] and for the K-shell and total ICCs of high multipolarity transitions (total, K-, L-, M-shells of E3 and M3 and K-shell of M4). Experimental data sets are also compared with the theoretical values of these specific calculations

Recent Applications of Fluorescence Recovery after Photobleaching (FRAP to Membrane Bio-Macromolecules

Directory of Open Access Journals (Sweden)

Gamal Rayan

2010-06-01

Full Text Available This review examines some recent applications of fluorescence recovery after photobleaching (FRAP to biopolymers, while mainly focusing on membrane protein studies. Initially, we discuss the lateral diffusion of membrane proteins, as measured by FRAP. Then, we talk about the use of FRAP to probe interactions between membrane proteins by obtaining fundamental information such as geometry and stoichiometry of the interacting complex. Afterwards, we discuss some applications of FRAP at the cellular level as well as the level of organisms. We conclude by comparing diffusion coefficients obtained by FRAP and several other alternative methods.

Relationship Between Magnitude of Applied Spin Recovery Moment and Ensuing Number of Recovery Turns

Science.gov (United States)

Anglin, Ernie L.

1967-01-01

An analytical study has been made to investigate the relationship between the magnitude of the applied spin recovery moment and the ensuing number of turns made during recovery from a developed spin with a view toward determining how to interpolate or extrapolate spin recovery results with regard to determining the amount of control required for a satisfactory recovery. Five configurations were used which are considered to be representative of modern airplanes: a delta-wing fighter, a stub-wing research vehicle, a boostglide configuration, a supersonic trainer, and a sweptback-wing fighter. The results obtained indicate that there is a direct relationship between the magnitude of the applied spin recovery moments and the ensuing number of recovery turns made and that this relationship can be expressed in either simple multiplicative or exponential form. Either type of relationship was adequate for interpolating or extrapolating to predict turns required for recovery with satisfactory accuracy for configurations having relatively steady recovery motions. Any two recoveries from the same developed spin condition can be used as a basis for the predicted results provided these recoveries are obtained with the same ratio of recovery control deflections. No such predictive method can be expected to give satisfactory results for oscillatory recoveries.

Digital video steganalysis using motion vector recovery-based features.

Science.gov (United States)

Deng, Yu; Wu, Yunjie; Zhou, Linna

2012-07-10

As a novel digital video steganography, the motion vector (MV)-based steganographic algorithm leverages the MVs as the information carriers to hide the secret messages. The existing steganalyzers based on the statistical characteristics of the spatial/frequency coefficients of the video frames cannot attack the MV-based steganography. In order to detect the presence of information hidden in the MVs of video streams, we design a novel MV recovery algorithm and propose the calibration distance histogram-based statistical features for steganalysis. The support vector machine (SVM) is trained with the proposed features and used as the steganalyzer. Experimental results demonstrate that the proposed steganalyzer can effectively detect the presence of hidden messages and outperform others by the significant improvements in detection accuracy even with low embedding rates.

Measuring Resource Inequality: The Gini Coefficient

Directory of Open Access Journals (Sweden)

Michael T. Catalano

2009-07-01

Full Text Available This paper stems from work done by the authors at the Mathematics for Social Justice Workshop held in June of 2007 at Middlebury College. We provide a description of the Gini coefficient and some discussion of how it can be used to promote quantitative literacy skills in mathematics courses. The Gini Coefficient was introduced in 1921 by Italian statistician Corrado Gini as a measure of inequality. It is defined as twice the area between two curves. One, the Lorenz curve for a given population with respect to a given resource, represents the cumulative percentage of the resource as a function of the cumulative percentage of the population that shares that percentage of the resource. The second curve is the line y = x which is the Lorenz curve for a population which shares the resource equally. The Gini coefficient can be interpreted as the percentage of inequality represented in the population with respect to the given resource. We propose that the Gini coefficient can be used to enhance students’ understanding of calculus concepts and provide practice for students in using both calculus and quantitative literacy skills. Our examples are based mainly on distribution of energy resources using publicly available data from the Energy Information Agency of the United States Government. For energy resources within the United States, we find that by household, the Gini coefficient is 0.346, while using the 51 data points represented by the states and Washington D.C., the Gini coefficient is 0.158. When we consider the countries of the world as a population of 210, the Gini coefficient is 0.670. We close with ideas for questions which can be posed to students and discussion of the experiences two other mathematics instructors have had incorporating the Gini coefficient into pre-calculus-level mathematics classes.

Revised Mark 22 coolant temperature coefficients

International Nuclear Information System (INIS)

Graves, W.E.

1987-01-01

Coolant temperature coefficients for the Mark 22 charge published previously are non-conservative because of the neglect of a significant mechanism which has a positive contribution to reactivity. Even after correcting for this effect, dynamic tests made on a Mark VIB charge in the early 60's suggest the results are still non-conservative. This memorandum takes both of these sources of information into account in making a best estimate of the prompt (coolant plus metal) temperature coefficient. Although no safety issues arise from this work (the overall temperature coefficient still strongly contributes to reactor stability), it is obviously desirable to use best estimates for prompt coefficients in limits and other calculations

Transport Coefficients from Large Deviation Functions

Directory of Open Access Journals (Sweden)

Chloe Ya Gao

2017-10-01

Full Text Available We describe a method for computing transport coefficients from the direct evaluation of large deviation functions. This method is general, relying on only equilibrium fluctuations, and is statistically efficient, employing trajectory based importance sampling. Equilibrium fluctuations of molecular currents are characterized by their large deviation functions, which are scaled cumulant generating functions analogous to the free energies. A diffusion Monte Carlo algorithm is used to evaluate the large deviation functions, from which arbitrary transport coefficients are derivable. We find significant statistical improvement over traditional Green–Kubo based calculations. The systematic and statistical errors of this method are analyzed in the context of specific transport coefficient calculations, including the shear viscosity, interfacial friction coefficient, and thermal conductivity.

Transport Coefficients from Large Deviation Functions

Science.gov (United States)

Gao, Chloe; Limmer, David

2017-10-01

We describe a method for computing transport coefficients from the direct evaluation of large deviation function. This method is general, relying on only equilibrium fluctuations, and is statistically efficient, employing trajectory based importance sampling. Equilibrium fluctuations of molecular currents are characterized by their large deviation functions, which is a scaled cumulant generating function analogous to the free energy. A diffusion Monte Carlo algorithm is used to evaluate the large deviation functions, from which arbitrary transport coefficients are derivable. We find significant statistical improvement over traditional Green-Kubo based calculations. The systematic and statistical errors of this method are analyzed in the context of specific transport coefficient calculations, including the shear viscosity, interfacial friction coefficient, and thermal conductivity.

Power coefficient anomaly in JOYO

Energy Technology Data Exchange (ETDEWEB)

Yamamoto, H

1980-12-15

Operation of the JOYO experimental fast reactor with the MK-I core has been divided into two phases: (1) 50 MWt power ascension and operation; and (2) 75 MWt power ascension and operation. The 50 MWt power-up tests were conducted in August 1978. In these tests, the measured reactivity loss due to power increases from 15 MWt to 50 MWt was 0.28% ..delta.. K/K, and agreed well with the predicted value of 0.27% ..delta.. K/K. The 75 MWt power ascension tests were conducted in July-August 1979. In the process of the first power increase above 50 MWt to 65 MWt conducted on July 11, 1979, an anomalously large negative power coefficient was observed. The value was about twice the power coefficient values measured in the tests below 50 MW. In order to reproduce the anomaly, the reactor power was decreased and again increased up to the maximum power of 65 MWt. However, the large negative power coefficient was not observed at this time. In the succeeding power increase from 65 MWt to 75 MWt, a similar anomalous power coefficient was again observed. This anomaly disappeared in the subsequent power ascensions to 75 MWt, and the magnitude of the power coefficient gradually decreased with power cycles above the 50 MWt level.

Effects of polymerization degree on recovery behavior of PVA/PVP hydrogels as potential articular cartilage prosthesis after fatigue test

Directory of Open Access Journals (Sweden)

Y. Shi

2016-02-01

Full Text Available Poly (vinyl alcohol/poly (vinyl pyrrolidone (PVA/PVP hydrogels with various polymerization degrees of PVA were synthesized by a repeated freezing-thawing method. The influence of polymerization degree on microstructure, water content, friction coefficient, compressive fatigue and recovery properties of PVA/PVP hydrogels were investigated. The results showed that higher polymerization degree resulted in larger compressive modulus and lower friction coefficient. The fatigue behaviors of PVA/PVP hydrogels were evaluated under sinusoidal compressive loading from 200 to 800 N at 5 Hz for up to 50 000 cycles. The unconfined uniaxial compressive tests of PVA/PVP hydrogels were performed before and after fatigue test. During the fatigue test, the height of the hydrogel rapidly decreased at first and gradually became stable with loading cycles. The compressive tangent modulus measured 0 h after fatigue was significantly larger than the values obtained before test, and then the modulus recovered to its original level for 48 h after test. However, the geometry of hydrogels could not return to the original level due to the creep effects. PVA/PVP hydrogels prepared with lower polymerization degree showed better recovery capability than that prepared with high polymerization degree.

Tropospheric mid-latitude geopotential wave characteristics associated with strong wind events in the North Atlantic/European region

Science.gov (United States)

Wild, Simon; Simmonds, Ian; Leckebusch, Gregor C.

2015-04-01

The variability of strong synoptic scale wind events in the mid-latitudes have long been linked to baroclinic wave activity in the mid troposphere. Previous studies have also shown that greater amplitudes of planetary waves in the mid troposphere are likely to increase the occurrence of regional extremes in temperature and precipitation. In this study we examine whether characteristics of planetary and synoptic mid-latitude waves show systematic anomalies in the North Atlantic/ European region which can be related to the occurrence of a strong surface wind event. We will mainly focus on two questions: 1) Do amplitudes for waves with different wave lengths show a systematic anomaly when a strong wind event occurs? 2) Can phases of the individual wave components be detected that favour strong wind events? In order to decompose the mid-tropospheric flow into longitudinal waves we employ the fast Fourier transform to the meridional mean of the geopotential height in 500hPa between 35° and 60°N for i) the entire latitude belt and ii) for a North Atlantic/European sector (36°W to 36°E). Our definition of strong wind events is based on the Storm Severity Index (SSI) alongside a wind tracking algorithm identifying areas of exceedances of the local 98th percentile of the 10m wind speed. First results using ERA-Interim Reanalysis from 1979 - 2014 for the extended winter season (ONDJFM) for the 50 most intense strong wind systems with respect to the SSI reveal a greater amplitude for all investigated wave numbers. Especially waves with wave lengths below 2000km show an increase of about 25% of the daily standard deviation on average. The distribution of wave phases for the different wave numbers with respect to the location of a strong wind event shows a less homogenous picture. There is however a high proportion of events that can be associated with phases around 3π/4 and 5π/4 of waves with lengths of around 6000km, equivalent to wave number 5 on a planetary scale

Spousal recovery support, recovery experiences, and life satisfaction crossover among dual-earner couples.

Science.gov (United States)

Park, YoungAh; Fritz, Charlotte

2015-03-01

Research has indicated the importance of recovery from work stress for employee well-being and work engagement. However, very little is known about the specific factors that may support or hinder recovery in the context of dual-earner couples. This study proposes spousal recovery support as a potential resource that dual-earner couples can draw on to enhance their recovery experiences and well-being. It was hypothesized that spousal recovery support would be related to the recipient spouse's life satisfaction via his or her own recovery experiences (i.e., psychological detachment, relaxation, and mastery experiences). The study further investigated the crossover of life satisfaction between working spouses as a potential outcome of recovery processes. Data from 318 full-time employed married couples in South Korea were analyzed using structural equation modeling. Results showed that spousal recovery support was positively related to all 3 recovery experiences of the recipient spouse. Moreover, this recovery support was related to the recipient spouse's life satisfaction via relaxation and mastery experiences. Unexpectedly, psychological detachment was negatively related to life satisfaction, possibly indicating a suppression effect. Life satisfaction crossed over between working spouses. No gender differences were found in the hypothesized paths. Based on these findings, theoretical and practical implications are discussed, and future research directions are presented. PsycINFO Database Record (c) 2015 APA, all rights reserved.

Temperature dependence of Kerr coefficient and quadratic polarized optical coefficient of a paraelectric Mn:Fe:KTN crystal

Directory of Open Access Journals (Sweden)

Qieni Lu

2015-08-01

Full Text Available We measure temperature dependence on Kerr coefficient and quadratic polarized optical coefficient of a paraelectric Mn:Fe:KTN crystal simultaneously in this work, based on digital holographic interferometry (DHI. And the spatial distribution of the field-induced refractive index change can also be visualized and estimated by numerically retrieving sequential phase maps of Mn:Fe:KTN crystal from recording digital holograms in different states. The refractive indices decrease with increasing temperature and quadratic polarized optical coefficient is insensitive to temperature. The experimental results suggest that the DHI method presented here is highly applicable in both visualizing the temporal and spatial behavior of the internal electric field and accurately measuring electro-optic coefficient for electrooptical media.

SOVENT BASED ENHANCED OIL RECOVERY FOR IN-SITU UPGRADING OF HEAVY OIL SANDS

Energy Technology Data Exchange (ETDEWEB)

Munroe, Norman

2009-01-30

With the depletion of conventional crude oil reserves in the world, heavy oil and bitumen resources have great potential to meet the future demand for petroleum products. However, oil recovery from heavy oil and bitumen reservoirs is much more difficult than that from conventional oil reservoirs. This is mainly because heavy oil or bitumen is partially or completely immobile under reservoir conditions due to its extremely high viscosity, which creates special production challenges. In order to overcome these challenges significant efforts were devoted by Applied Research Center (ARC) at Florida International University and The Center for Energy Economics (CEE) at the University of Texas. A simplified model was developed to assess the density of the upgraded crude depending on the ratio of solvent mass to crude oil mass, temperature, pressure and the properties of the crude oil. The simplified model incorporated the interaction dynamics into a homogeneous, porous heavy oil reservoir to simulate the dispersion and concentration of injected CO2. The model also incorporated the characteristic of a highly varying CO2 density near the critical point. Since the major challenge in heavy oil recovery is its high viscosity, most researchers have focused their investigations on this parameter in the laboratory as well as in the field resulting in disparaging results. This was attributed to oil being a complex poly-disperse blend of light and heavy paraffins, aromatics, resins and asphaltenes, which have diverse behaviors at reservoir temperature and pressures. The situation is exacerbated by a dearth of experimental data on gas diffusion coefficients in heavy oils due to the tedious nature of diffusivity measurements. Ultimately, the viscosity and thus oil recovery is regulated by pressure and its effect on the diffusion coefficient and oil swelling factors. The generation of a new phase within the crude and the differences in mobility between the new crude matrix and the

Myocardial T1 mapping and determination of partition coefficients at 3 tesla: comparison between gadobenate dimeglumine and gadofosveset trisodium

Directory of Open Access Journals (Sweden)

Marcelo Souto Nacif

2018-01-01

Full Text Available Abstract Objective: To compare an albumin-bound gadolinium chelate (gadofosveset trisodium and an extracellular contrast agent (gadobenate dimeglumine, in terms of their effects on myocardial longitudinal (T1 relaxation time and partition coefficient. Materials and Methods: Study subjects underwent two imaging sessions for T1 mapping at 3 tesla with a modified look-locker inversion recovery (MOLLI pulse sequence to obtain one pre-contrast T1 map and two post-contrast T1 maps (mean 15 and 21 min, respectively. The partition coefficient was calculated as ΔR1myocardium /ΔR1blood , where R1 is 1/T1. Results: A total of 252 myocardial and blood pool T1 values were obtained in 21 healthy subjects. After gadolinium administration, the myocardial T1 was longer for gadofosveset than for gadobenate, the mean difference between the two contrast agents being −7.6 ± 60 ms (p = 0.41. The inverse was true for the blood pool T1, which was longer for gadobenate than for gadofosveset, the mean difference being 56.5 ± 67 ms (p < 0.001. The partition coefficient (λ was higher for gadobenate than gadofosveset (0.41 vs. 0.33, indicating slower blood pool washout for gadofosveset than for gadobenate. Conclusion: Myocardial T1 times did not differ significantly between gadobenate and gadofosveset. At typical clinical doses of the contrast agents, partition coefficients were significantly lower for the intravascular contrast agent than for the extravascular agent.

The recovery imperative: a critical examination of mid-life women's recovery from depression.

Science.gov (United States)

O'Brien, Wendy

2012-08-01

Australia, like other countries in neo-liberal democracies, is grappling with the gendered health 'problem' of depression. More concerning is the issue of recovery and relapse, with depression being the third largest cause of disability-adjusted life years (DALY). In addition, advanced liberal discourses of health position recovery as an exercise of individual responsibility to return to a functioning and productive norm and prevent recurrence. This moral enterprise of health articulates a 'recovery imperative' which overlooks the gendered context which may have created the conditions for women's depression and may in turn impede their recovery. Drawing on insights from governmentality and feminist post-structuralism, the article critically examines the effects of normalized recovery discourses on women's subjectivities. Data for the study were collected between 2005 and 2007 through in-depth interviews with 31 mid-life Australian women. Three key themes; 'in' recovery, 'eight out of ten' recovered, and recovering the authentic self, illustrate how the 'recovery imperative' may be implicated in perpetuating the cycle of recovery and relapse. Copyright © 2012 Elsevier Ltd. All rights reserved.

Form coefficient of helical toroidal solenoids

International Nuclear Information System (INIS)

Amelin, V.Z.; Kunchenko, V.B.

1982-01-01

For toroidal solenoids with continuous spiral coil, winded according to the laws of equiinclined and simple cylindrical spirals with homogeneous, linearly increasing to the coil periphery and ''Bitter'' distribution of current density, the analytical expressions for the dependence between capacity consumed and generated magnetic field, expressions for coefficients of form similar to Fabry coefficient for cylindrical solenoids are obtained and dependence of the form coefficient and relative volume of solenoid conductor on the number of revolutions of screw line per one circumvention over the large torus radius is also investigated. Analytical expressions of form coefficients and graphical material permit to select the optimum geometry as to capacity consumed both for spiral (including ''force-free'') and conventional toroidal solenoids of magnetic systems in thermonulear installations

Friction coefficient dependence on electrostatic tribocharging.

Science.gov (United States)

Burgo, Thiago A L; Silva, Cristiane A; Balestrin, Lia B S; Galembeck, Fernando

2013-01-01

Friction between dielectric surfaces produces patterns of fixed, stable electric charges that in turn contribute electrostatic components to surface interactions between the contacting solids. The literature presents a wealth of information on the electronic contributions to friction in metals and semiconductors but the effect of triboelectricity on friction coefficients of dielectrics is as yet poorly defined and understood. In this work, friction coefficients were measured on tribocharged polytetrafluoroethylene (PTFE), using three different techniques. As a result, friction coefficients at the macro- and nanoscales increase many-fold when PTFE surfaces are tribocharged, but this effect is eliminated by silanization of glass spheres rolling on PTFE. In conclusion, tribocharging may supersede all other contributions to macro- and nanoscale friction coefficients in PTFE and probably in other insulating polymers.

Battleground Energy Recovery Project

Energy Technology Data Exchange (ETDEWEB)

Bullock, Daniel [USDOE Gulf Coast Clean Energy Application Center, Woodlands, TX (United States)

2011-12-31

In October 2009, the project partners began a 36-month effort to develop an innovative, commercial-scale demonstration project incorporating state-of-the-art waste heat recovery technology at Clean Harbors, Inc., a large hazardous waste incinerator site located in Deer Park, Texas. With financial support provided by the U.S. Department of Energy, the Battleground Energy Recovery Project was launched to advance waste heat recovery solutions into the hazardous waste incineration market, an area that has seen little adoption of heat recovery in the United States. The goal of the project was to accelerate the use of energy-efficient, waste heat recovery technology as an alternative means to produce steam for industrial processes. The project had three main engineering and business objectives: Prove Feasibility of Waste Heat Recovery Technology at a Hazardous Waste Incinerator Complex; Provide Low-cost Steam to a Major Polypropylene Plant Using Waste Heat; and Create a Showcase Waste Heat Recovery Demonstration Project.

The adsorption potential and recovery of thallium using green micro-algae from eutrophic water sources.

Science.gov (United States)

Birungi, Z S; Chirwa, E M N

2015-12-15

Thallium (Tl) is a highly volatile and toxic heavy metal regarded to cause pollution even at very low concentrations of several parts per million. Despite the extremely high risk of Tl in the environment, limited information on removal/recovery exists. The study focussed on the use of green algae to determine the sorption potential and recovery of Tl. From the study, removal efficiency was achieved at 100% for lower concentrations of ≥150 mg/L of Tl. At higher concentrations in a range of 250-500 mg/L, the performance of algae was still higher with sorption capacity (qmax) between 830 and 1000 mg/g. Generally, Chlorella vulgaris was the best adsorbent with a high qmax and lower affinity of 1000 mg/g and 1.11 L/g, respectively. When compared to other studies on Tl adsorption, the tested algae showed a better qmax than most adsorbents. The kinetic studies showed better correlation co-efficient of ≤0.99 for Pseudo-second order model than the first order model. Recovery was achieved highest for C. vulgaris using nitric acid at 93.3%. The strongest functional groups responsible for Tl binding on the algal cell wall were carboxyl and phenols. Green algae from freshwater bodies showed significant potential for Tl removal/recovery from industrial wastewater. Copyright © 2015 Elsevier B.V. All rights reserved.

Learning how to recover from job stress: effects of a recovery training program on recovery, recovery-related self-efficacy, and well-being.

Science.gov (United States)

Hahn, Verena C; Binnewies, Carmen; Sonnentag, Sabine; Mojza, Eva J

2011-04-01

This quasi-experimental study evaluated the effects of a recovery training program on recovery experiences (psychological detachment from work, relaxation, mastery experiences, and control during off-job time), recovery-related self-efficacy, and well-being outcomes. The training comprised two sessions held one week apart. Recovery experiences, recovery-related self-efficacy, and well-being outcomes were measured before the training (T1) and one week (T2) and three weeks (T3) after the training. A training group consisting of 48 individuals and a waitlist control group of 47 individuals were compared (N = 95). Analyses of covariance revealed an increase in recovery experiences at T2 and T3 (for mastery only at T2). Recovery-related self-efficacy and sleep quality increased at T2 and T3, perceived stress and state negative affect decreased at T3. No training effects were found for emotional exhaustion.

Catastrophic Incident Recovery: Long-Term Recovery from an Anthrax Event Symposium

Energy Technology Data Exchange (ETDEWEB)

Lesperance, Ann M.

2008-06-30

On March 19, 2008, policy makers, emergency managers, and medical and Public Health officials convened in Seattle, Washington, for a workshop on Catastrophic Incident Recovery: Long-Term Recovery from an Anthrax Event. The day-long symposium was aimed at generating a dialogue about restoration and recovery through a discussion of the associated challenges that impact entire communities, including people, infrastructure, and critical systems.

Friction coefficient dependence on electrostatic tribocharging

Science.gov (United States)

Burgo, Thiago A. L.; Silva, Cristiane A.; Balestrin, Lia B. S.; Galembeck, Fernando

2013-01-01

Friction between dielectric surfaces produces patterns of fixed, stable electric charges that in turn contribute electrostatic components to surface interactions between the contacting solids. The literature presents a wealth of information on the electronic contributions to friction in metals and semiconductors but the effect of triboelectricity on friction coefficients of dielectrics is as yet poorly defined and understood. In this work, friction coefficients were measured on tribocharged polytetrafluoroethylene (PTFE), using three different techniques. As a result, friction coefficients at the macro- and nanoscales increase many-fold when PTFE surfaces are tribocharged, but this effect is eliminated by silanization of glass spheres rolling on PTFE. In conclusion, tribocharging may supersede all other contributions to macro- and nanoscale friction coefficients in PTFE and probably in other insulating polymers. PMID:23934227

Picturing recovery: a photovoice exploration of recovery dimensions among people with serious mental illness.

Science.gov (United States)

Cabassa, Leopoldo J; Nicasio, Andel; Whitley, Rob

2013-09-01

Recovery from mental disorders encompasses multiple interrelated dimensions. This study used photovoice to explore how individuals with serious mental illness and a history of substance abuse and homelessness envisioned their recovery. A dimensional recovery model was applied to examine how the interrelationships between recovery dimensions supported consumers' recovery journeys. Photovoice is a participatory research method that empowers people by giving them cameras to document their experiences and inform social action. Sixteen consumers recruited from two supported housing agencies participated in six weekly sessions to which they brought photographs that they took of persons and events in their lives that reflected recovery and wellness and discussed the meaning of the photographs in individual interviews and group sessions. The authors used pile-sorting, grounded theory, and a deductive template-analytic technique to analyze narrative and visual data. Spirituality, life achievements, and receiving and providing support were the most salient themes that emerged from the analysis and illustrate beneficial interrelationships between recovery dimensions. Participants discussed how they relied on their spirituality to support their sobriety and cope with addictions-aspects of clinical recovery. Educational and vocational achievements represented gains in functioning that contributed to increasing self-esteem and self-agency and reducing self-stigma. Social dimensions of recovery, such as receiving and giving support to loved ones, rippled through consumers' lives reducing isolation and enhancing their self-worth. The findings illustrate the value of participatory methods to understand what recovery signified to people with serious mental illness and how understanding the interrelationships between recovery dimensions can inform recovery-oriented services.

Gravity Field Parameter Estimation Using QR Factorization

Science.gov (United States)

Klokocnik, J.; Wagner, C. A.; McAdoo, D.; Kostelecky, J.; Bezdek, A.; Novak, P.; Gruber, C.; Marty, J.; Bruinsma, S. L.; Gratton, S.; Balmino, G.; Baboulin, M.

2007-12-01

This study compares the accuracy of the estimated geopotential coefficients when QR factorization is used instead of the classical method applied at our institute, namely the generation of normal equations that are solved by means of Cholesky decomposition. The objective is to evaluate the gain in numerical precision, which is obtained at considerable extra cost in terms of computer resources. Therefore, a significant increase in precision must be realized in order to justify the additional cost. Numerical simulations were done in order to examine the performance of both solution methods. Reference gravity gradients were simulated, using the EIGEN-GL04C gravity field model to degree and order 300, every 3 seconds along a near-circular, polar orbit at 250 km altitude. The simulation spanned a total of 60 days. A polar orbit was selected in this simulation in order to avoid the 'polar gap' problem, which causes inaccurate estimation of the low-order spherical harmonic coefficients. Regularization is required in that case (e.g., the GOCE mission), which is not the subject of the present study. The simulated gravity gradients, to which white noise was added, were then processed with the GINS software package, applying EIGEN-CG03 as the background gravity field model, followed either by the usual normal equation computation or using the QR approach for incremental linear least squares. The accuracy assessment of the gravity field recovery consists in computing the median error degree-variance spectra, accumulated geoid errors, geoid errors due to individual coefficients, and geoid errors calculated on a global grid. The performance, in terms of memory usage, required disk space, and CPU time, of the QR versus the normal equation approach is also evaluated.

Energy Recovery from a Non-Linear Electromagnetic System

Directory of Open Access Journals (Sweden)

Kęcik Krzysztof

2018-03-01

Full Text Available The paper presents study of a pseudo-magnetic levitation system (pseudo-maglev dedicated for energy harvesting. The idea rely on motion of a pseudo-levitating magnet in a coil’s terminal. The study based on real prototype harvester system, which in the pendulum dynamic vibration absorber is applied. For some parameters, the stability loss caused by the period doubling bifurcation is detected. The coexistence of two stable solutions, one of which is much better for energy harvesting is observed. The influence of the pseudo-maglev parameters on the recovered current and stability of the periodic solutions is presented in detail. The obtained results show, that the best energy recovery occurs for the high pseudo-maglev stiffness and close to the coil resistance. The amplitude’s excitation, the load resistances and the coupling coefficient strongly influence on the system’s response.

Improved NGL recovery designs maximize operating flexibility and product recoveries

International Nuclear Information System (INIS)

Wilkinson, J.D.; Hudson, H.M.

1992-01-01

This paper reports that the historically cyclical nature in the market for ethane and propane has demonstrated the need for flexible natural gas liquids (NGL) recovery plants. NEwly developed and patented processes are now available which can provide ultra-high recovery of ethane (95%+) when demand for ethane is high and provide essentially complete ethane rejection without the normally concomitant reduction in propane recovery. This provides plant operators the flexibility to respond more readily to NGL market conditions, thus maximizing plant operating profits. The new process designs provide this flexibility without increasing utility requirements. In fact, utility consumption is often lower when compared to conventional designs. This same process technology can also be easily retrofit into existing plants with relatively quick payout of the modifications from both recovery and efficiency improvements

Calculation of transport coefficients in an axisymmetric plasma

International Nuclear Information System (INIS)

Shumaker, D.E.

1976-01-01

A method of calculating the transport coefficient in an axisymmetric toroidal plasma is presented. This method is useful in calculating the transport coefficients in a Tokamak plasma confinement device. The particle density and temperature are shown to be a constant on a magnetic flux surface. Transport equations are given for the total particle flux and total energy flux crossing a closed toroidal surface. Also transport equations are given for the toroidal magnetic flux. A computer code was written to calculate the transport coefficients for a three species plasma, electrons and two species of ions. This is useful for calculating the transport coefficients of a plasma which contains impurities. It was found that the particle and energy transport coefficients are increased by a large amount, and the transport coefficients for the toroidal magnetic field are reduced by a small amount. For example, a deuterium plasma with 1.3 percent oxygen, one of the particle transport coefficients is increased by a factor of about four. The transport coefficients for the toroidal magnetic flux are reduced by about 20 percent. The increase in the particle transport coefficient is due to the collisional scattering of the deuterons by the heavy oxygen ions which is larger than the deuteron electron scattering, the normal process for particle transport in a two species plasma. The reduction in the toroidal magnetic flux transport coefficients are left unexplained

Transfer coefficients in ultracold strongly coupled plasma

Science.gov (United States)

Bobrov, A. A.; Vorob'ev, V. S.; Zelener, B. V.

2018-03-01

We use both analytical and molecular dynamic methods for electron transfer coefficients in an ultracold plasma when its temperature is small and the coupling parameter characterizing the interaction of electrons and ions exceeds unity. For these conditions, we use the approach of nearest neighbor to determine the average electron (ion) diffusion coefficient and to calculate other electron transfer coefficients (viscosity and electrical and thermal conductivities). Molecular dynamics simulations produce electronic and ionic diffusion coefficients, confirming the reliability of these results. The results compare favorably with experimental and numerical data from earlier studies.

Radionuclides distribution coefficient of soil to soil-solution

International Nuclear Information System (INIS)

1990-06-01

The present book addresses various issues related with the coefficient of radionuclides distribution between soil and soil solution. It consists of six sections and two appendices. The second section, following an introductory one, describes the definition of the coefficient and a procedures of its calculation. The third section deals with the application of the distribution coefficient to the prediction of movements of radionuclides through soil. Various methods for measuring the coefficient are described in the fourth section. The next section discusses a variety of factors (physical and chemical) that can affect the distribution coefficient. Measurements of the coefficient for different types of oils are listed in the sixth section. An appendix is attached to the book to show various models that can be helpful in applying the coefficient of distribution of radionuclides moving from soil into agricultural plants. (N.K.)

Soccer Ball Lift Coefficients via Trajectory Analysis

Science.gov (United States)

Goff, John Eric; Carre, Matt J.

2010-01-01

We performed experiments in which a soccer ball was launched from a machine while two high-speed cameras recorded portions of the trajectory. Using the trajectory data and published drag coefficients, we extracted lift coefficients for a soccer ball. We determined lift coefficients for a wide range of spin parameters, including several spin…

Business recovery: an assessment framework.

Science.gov (United States)

Stevenson, Joanne R; Brown, Charlotte; Seville, Erica; Vargo, John

2018-07-01

This paper presents a Business Recovery Assessment Framework (BRAF) to help researchers and practitioners design robust, repeatable, and comparable studies of business recovery in various post-disruption contexts. Studies assessing business recovery without adequately considering the research aims, recovery definitions, and indicators can produce misleading findings. The BRAF is composed of a series of steps that guide the decisions that researchers need to make to ensure: (i) that recovery is indeed being measured; (ii) that the indicators of recovery that are selected align with the objectives of the study and the definition of recovery; and, where necessary, (iii) that appropriate comparative control variables are in place. The paper draws on a large dataset of business surveys collected following the earthquakes in Canterbury, New Zealand, on 4 September 2010 and 22 February 2011 to demonstrate the varied conclusions that different recovery indicators can produce and to justify the need for a systematic approach to business recovery assessments. © 2018 The Author(s). Disasters © Overseas Development Institute, 2018.

Thermal Recovery from Cold-Working in Type K Bare-Wire Thermocouples

Science.gov (United States)

Greenen, A. D.; Webster, E. S.

2017-12-01

Cold-working of most thermocouples has a significant, direct impact on the Seebeck coefficient which can lead to regions of thermoelectric inhomogeneity and accelerated drift. Cold-working can occur during the wire swaging process, when winding the wire onto a bobbin, or during handling by the end user—either accidentally or deliberately. Swaging-induced cold-work in thermocouples, if uniformly applied, may result in a high level of homogeneity. However, on exposure to elevated temperatures, the subsequent recovery process from the cold-working can then result in significant drift, and this can in turn lead to erroneous temperature measurements, often in excess of the specified manufacturer tolerances. Several studies have investigated the effects of cold-work in Type K thermocouples usually by bending, or swaging. However, the amount of cold-work applied to the thermocouple is often difficult to quantify, as the mechanisms for applying the strains are typically nonlinear when applied in this fashion. A repeatable level of cold-working is applied to the different wires using a tensional loading apparatus to apply a known yield displacement to the thermoelements. The effects of thermal recovery from cold-working can then be accurately quantified as a function of temperature, using a linear gradient furnace and a high-resolution homogeneity scanner. Variation in these effects due to differing alloy compositions in Type K wire is also explored, which is obtained by sourcing wire from a selection of manufacturers. The information gathered in this way will inform users of Type K thermocouples about the potential consequences of varying levels of cold-working and its impact on the Seebeck coefficient at a range of temperatures between ˜ 70°C and 600° C. This study will also guide users on the temperatures required to rapidly alleviate the effects of cold-working using thermal annealing treatments.

Monitoring device for local power peaking coefficients

International Nuclear Information System (INIS)

Mihashi, Ishi

1987-01-01

Purpose: To determine and monitor the local power peaking coefficients by a method not depending on the combination of fuel types. Constitution: Representative values for the local power distribution can be obtained by determining corresponding burn-up degrees based on the burn-up degree of each of fuel assembly segments obtained in a power distribution monitor and by the interpolation and extrapolation of void coefficients. The typical values are multiplied with compensation coefficients for the control rod effect and coefficients for compensating the effect of adjacent fuel assemblies in a calculation device to obtain typical values for the present local power distribution compensated with all of the effects. Further, the calculation device compares them with typical values of the present local power distribution to obtain an aimed local power peaking coefficient as the maximum value thereof. According to the present invention, since the local power peaking coefficients can be determined not depending on the combination of the kind of fuels, if the combination of fuel assemblies is increased upon fuel change, the amount of operation therefor is not increased. (Kamimura, M.)

Monitoring device for local power peaking coefficient

International Nuclear Information System (INIS)

Mitsuhashi, Ishi

1987-01-01

Purpose: To monitor the local power peaking coefficients obtained by the method not depending on the combination of fuel types. Method: A plurality of representative values for the local power distribution determined by the nuclear constant calculation for one fuel assembly are memorized regarding each of the burn-up degree and the void coefficient on every positions and fuel types in fuel rod assemblies. While on the other hand, the representative values for the local power distribution as described above are compensated by a compensation coefficient considering the effect of adjacent segments and a control rod compensation coefficient considering the effect due to the control rod insertion relative to the just-mentioned compensation coefficient. Then, the maximum value among them is selected to determine the local power peaking coefficient at each of the times and each of the segments, which is monitored. According to this system, the calculation and the working required for the fitting work depending on the combination of fuel types are no more required at all to facilitate the maintenance as well. (Horiuchi, T.)

Properties of Traffic Risk Coefficient

Science.gov (United States)

Tang, Tie-Qiao; Huang, Hai-Jun; Shang, Hua-Yan; Xue, Yu

2009-10-01

We use the model with the consideration of the traffic interruption probability (Physica A 387(2008)6845) to study the relationship between the traffic risk coefficient and the traffic interruption probability. The analytical and numerical results show that the traffic interruption probability will reduce the traffic risk coefficient and that the reduction is related to the density, which shows that this model can improve traffic security.

Water Recovery Project

Data.gov (United States)

National Aeronautics and Space Administration — The AES Water Recovery Project (WRP) is advancing environmental control and life support systems water recovery technologies to support human exploration beyond low...

EPA Recovery Mapper

Data.gov (United States)

U.S. Environmental Protection Agency — The EPA Recovery Mapper is an Internet interactive mapping application that allows users to discover information about every American Recovery and Reinvestment Act...

Analysis of an optimal resorption cogeneration using mass and heat recovery processes

International Nuclear Information System (INIS)

Lu, Yiji; Wang, Yaodong; Bao, Huashan; Yuan, Ye; Wang, Liwei; Roskilly, Anthony Paul

2015-01-01

Highlights: • Resorption cogeneration for electricity and refrigeration generation. • Mass and heat recovery to further improve the performance. • The first and second law analysis. - Abstract: This paper presents an optimised resorption cogeneration using mass and heat recovery to improve the performance of a novel resorption cogeneration fist proposed by Wang et al. This system combines ammonia-resorption technology and expansion machine into one loop, which is able to generate refrigeration and electricity from low-grade heat sources such as solar energy and industrial waste heat. Two sets of resorption cycle are designed to overcome the intermittent performance of the chemisorption and produce continuous/simultaneous refrigeration and electricity. In this paper, twelve resorption working pairs of salt complex candidates are analysed by the first law analysis using Engineering Equation Solver (EES). The optimal resorption working pairs from the twelve candidates under the driven temperature from 100 °C to 300 °C are identified. By applying heat/mass recovery, the coefficient of performance (COP) improvement is increased by 38% when the high temperature salt (HTS) is NiCl 2 and by 35% when the HTS is MnCl 2 . On the other hand, the energy efficiency of electricity has also been improved from 8% to 12% with the help of heat/mass recovery. The second law analysis has also been applied to investigate the exergy utilisation and identify the key components/processes. The highest second law efficiency is achieved as high as 41% by the resorption working pair BaCl 2 –MnCl 2 under the heat source temperature at 110 °C.

Prediction of friction coefficients for gases

Science.gov (United States)

Taylor, M. F.

1969-01-01

Empirical relations are used for correlating laminar and turbulent friction coefficients for gases, with large variations in the physical properties, flowing through smooth tubes. These relations have been used to correlate friction coefficients for hydrogen, helium, nitrogen, carbon dioxide and air.

Recovery from mental illness

DEFF Research Database (Denmark)

Petersen, Kirsten Schultz; Friis, Vivi Soegaard; Haxholm, Birthe Lodahl

2015-01-01

Mental health services strive to implement a recovery-oriented approach to rehabilitation. Little is known about service users' perception of the recovery approach. The aim is to explore the service user's perspectives on facilitators and barriers associated with recovery. Twelve residents living...

Computing exact Fourier series coefficients of IC rectilinear polygons from low-resolution fast Fourier coefficients

Science.gov (United States)

Scheibler, Robin; Hurley, Paul

2012-03-01

We present a novel, accurate and fast algorithm to obtain Fourier series coefficients from an IC layer whose description consists of rectilinear polygons on a plane, and how to implement it using off-the-shelf hardware components. Based on properties of Fourier calculus, we derive a relationship between the Discrete Fourier Transforms of the sampled mask transmission function and its continuous Fourier series coefficients. The relationship leads to a straightforward algorithm for computing the continuous Fourier series coefficients where one samples the mask transmission function, compute its discrete Fourier transform and applies a frequency-dependent multiplicative factor. The algorithm is guaranteed to yield the exact continuous Fourier series coefficients for any sampling representing the mask function exactly. Computationally, this leads to significant saving by allowing to choose the maximal such pixel size and reducing the fast Fourier transform size by as much, without compromising accuracy. In addition, the continuous Fourier series is free from aliasing and follows closely the physical model of Fourier optics. We show that in some cases this can make a significant difference, especially in modern very low pitch technology nodes.

Comparing linear probability model coefficients across groups

DEFF Research Database (Denmark)

Holm, Anders; Ejrnæs, Mette; Karlson, Kristian Bernt

2015-01-01

of the following three components: outcome truncation, scale parameters and distributional shape of the predictor variable. These results point to limitations in using linear probability model coefficients for group comparisons. We also provide Monte Carlo simulations and real examples to illustrate......This article offers a formal identification analysis of the problem in comparing coefficients from linear probability models between groups. We show that differences in coefficients from these models can result not only from genuine differences in effects, but also from differences in one or more...... these limitations, and we suggest a restricted approach to using linear probability model coefficients in group comparisons....

Diffusion coefficient of three-dimensional Yukawa liquids

International Nuclear Information System (INIS)

Dzhumagulova, K. N.; Ramazanov, T. S.; Masheeva, R. U.

2013-01-01

The purpose of this work is an investigation of the diffusion coefficient of the dust component in complex plasma. The computer simulation of the Yukawa liquids was made on the basis of the Langevin equation, which takes into account the influence of buffer plasma on the dust particles dynamics. The Green–Kubo relation was used to calculate the diffusion coefficient. Calculations of the diffusion coefficient for a wide range of the system parameters were performed. Using obtained numerical data, we constructed the interpolation formula for the diffusion coefficient. We also show that the interpolation formula correctly describes experimental data obtained under microgravity conditions

Diffusion coefficients of paracetamol in aqueous solutions

International Nuclear Information System (INIS)

Ribeiro, Ana C.F.; Barros, Marisa C.F.; Veríssimo, Luís M.P.; Santos, Cecilia I.A.V.; Cabral, Ana M.T.D.P.V.; Gaspar, Gualter D.; Esteso, Miguel A.

2012-01-01

Highlights: ► Mutual diffusion coefficients of paracetamol in aqueous dilute solutions. ► Influence of the thermodynamic factors on the variation of their mutual diffusion coefficients. ► Estimation of the mutual limiting diffusion coefficients of the molecular, D m 0 , and ionized forms, D ± 0 , of this drug. - Abstract: Binary mutual diffusion coefficients measured by the Taylor dispersion method, for aqueous solutions of paracetamol (PA) at concentrations from (0.001 to 0.050) mol·dm −3 at T = 298.15 K, are reported. From the Nernst–Hartley equation and our experimental results, the limiting diffusion coefficient of this drug and its thermodynamic factors are estimated, thereby contributing in this way to a better understanding of the structure of such systems and of their thermodynamic behaviour in aqueous solution at different concentrations.

Eigennoise Speech Recovery in Adverse Environments with Joint Compensation of Additive and Convolutive Noise

Directory of Open Access Journals (Sweden)

Trung-Nghia Phung

2015-01-01

Full Text Available The learning-based speech recovery approach using statistical spectral conversion has been used for some kind of distorted speech as alaryngeal speech and body-conducted speech (or bone-conducted speech. This approach attempts to recover clean speech (undistorted speech from noisy speech (distorted speech by converting the statistical models of noisy speech into that of clean speech without the prior knowledge on characteristics and distributions of noise source. Presently, this approach has still not attracted many researchers to apply in general noisy speech enhancement because of some major problems: those are the difficulties of noise adaptation and the lack of noise robust synthesizable features in different noisy environments. In this paper, we adopted the methods of state-of-the-art voice conversions and speaker adaptation in speech recognition to the proposed speech recovery approach applied in different kinds of noisy environment, especially in adverse environments with joint compensation of additive and convolutive noises. We proposed to use the decorrelated wavelet packet coefficients as a low-dimensional robust synthesizable feature under noisy environments. We also proposed a noise adaptation for speech recovery with the eigennoise similar to the eigenvoice in voice conversion. The experimental results showed that the proposed approach highly outperformed traditional nonlearning-based approaches.

Toward a Meaningful Definition of Recovery After Hip Fracture: Comparing Two Definitions for Community-Dwelling Older Adults.

Science.gov (United States)

Auais, Mohammad; Morin, Suzanne N; Finch, Lois; Ahmed, Sara; Mayo, Nancy

2018-02-14

To examine the course of recovery and resulting health-related quality of life (HRQL) after low-trauma hip fracture using 2 different definitions of recovery. Inception cohort with 8 assessments over 1 year. Participants were recruited from a tertiary-care hospital and followed up in the community. Community-dwelling hip fracture patients (N=47, 75% of all eligible; aged ≥65y). Not applicable. Prefracture functional level was used to identify subgroups of participants with similar trajectories of mobility over time. Recovery in functional mobility was defined in 2 ways: the "traditional" definition (return to prefracture level of functional mobility) and a "targeted recovery" definition (ability to climb 10 steps). Both were measured using the Lower Extremity Functional Scale. HRQL was measured using the RAND 36-Item Short-Form Health Survey. Participants were categorized into 3 subgroups with: low, medium, and high prefracture functional abilities. Agreement between the 2 definitions of recovery (quantified using κ coefficient) was strong for the medium group (.81; 95% confidence interval, .56-1.00), weak for the high group (.46; 95% confidence interval, 0.0-.99), and minimal for the low group (.12; 95% confidence interval, 0.0-.328). Contrary to the traditional definition, patients who achieved targeted recovery had statistically and clinically better HRQL than the rest of the cohort throughout the study (estimated average difference of 10.8 points on RAND 36-Item Short-Form Health Survey; 95% confidence interval, 6.67-15.07). The agreement between the 2 definitions of recovery ranged from minimal to strong according to patient group. Using a functional target to define recovery predicted HRQL better. It is vital to consider the definition of recovery carefully for research or clinical practice because it can influence subsequent decisions (eg, endorsing a specific intervention or discharging patients). Copyright © 2018 American Congress of Rehabilitation

Approximate reflection coefficients for a thin VTI layer

KAUST Repository

Hao, Qi

2017-09-18

We present an approximate method to derive simple expressions for the reflection coefficients of P- and SV-waves for a thin transversely isotropic layer with a vertical symmetry axis (VTI) embedded in a homogeneous VTI background. The layer thickness is assumed to be much smaller than the wavelengths of P- and SV-waves inside. The exact reflection and transmission coefficients are derived by the propagator matrix method. In the case of normal incidence, the exact reflection and transmission coefficients are expressed in terms of the impedances of vertically propagating P- and S-waves. For subcritical incidence, the approximate reflection coefficients are expressed in terms of the contrast in the VTI parameters between the layer and the background. Numerical examples are designed to analyze the reflection coefficients at normal and oblique incidence, and investigate the influence of transverse isotropy on the reflection coefficients. Despite giving numerical errors, the approximate formulae are sufficiently simple to qualitatively analyze the variation of the reflection coefficients with the angle of incidence.

Recovery and money management.

Science.gov (United States)

Rowe, Michael; Serowik, Kristin L; Ablondi, Karen; Wilber, Charles; Rosen, Marc I

2013-06-01

Social recovery and external money management are important approaches in contemporary mental health care, but little research has been done on the relationship between the two or on application of recovery principles to money management for people at risk of being assigned a representative payee or conservator. Out of 49 total qualitative interviews, 25 transcripts with persons receiving Social Security insurance or Social Security disability insurance who were at risk of being assigned a money manager were analyzed to assess the presence of recognized recovery themes. The recovery principles of self-direction and responsibility were strong themes in participant comments related to money management. Money management interventions should incorporate peoples' recovery-related motivations to acquire financial management skills as a means to direct and assume responsibility for one's finances. Staff involved in money management should receive training to support client's recovery-related goals. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

Radon emanation coefficients in sandy soils

International Nuclear Information System (INIS)

Holy, K.; Polaskova, A.; Baranova, A.; Sykora, I.; Hola, O.

1998-01-01

In this contribution the results of the study of an influence of the water content on the emanation coefficient for two sandy soil samples are reported. These samples were chosen on the because of the long-term continual monitoring of the 222 Rn concentration just in such types of soils and this radon concentration showed the significant variations during a year. These variations are chiefly given in connection with the soil moisture. Therefore, the determination of the dependence of the emanation coefficient of radon on the water content can help to evaluate the influence of the soil moisture variations of radon concentrations in the soil air. The presented results show that the emanation coefficient reaches the constant value in the wide interval of the water content for both sandy soil samples. Therefore, in the common range of the soil moisture (5 - 20 %) it is impossible to expect the variations of the radon concentration in the soil air due to the change of the emanation coefficient. The expressive changes of the radon concentration in the soil air can be observed in case of the significant decrease of the emanation coefficient during the soil drying when the water content decreases under 5 % or during the complete filling of the soil pores by the water. (authors)

Friction coefficient and limiter load test analysis by flexibility coefficient model of Hold-Down Spring of nuclear reactor vessel internals

Energy Technology Data Exchange (ETDEWEB)

Xie, Linjun [Zhejiang Univ. of Technology, Hangzhou (China). College of Mechanical Engineering; Xue, Guohong; Zhang, Ming [Shanghai Nuclear Engineering Research and Design Institute, Shanghai (China)

2017-11-15

The friction force between the contact surfaces of a reactor internal hold-down spring (HDS) and core barrel flanges can directly influence the axial stiffness of an HDS. However, friction coefficient cannot be obtained through theoretical analysis. This study performs a mathematical deduction of the physical model of an HDS. Moreover, a mathematical model of axial load P, displacement δ, and flexibility coefficient is established, and a set of test apparatuses is designed to simulate the preloading process of the HDS. According to the experimental research and theoretical analysis, P-δ curves and the flexibility coefficient λ are obtained in the loading processes of the HDS. The friction coefficient f of the M1000 HDS is further calculated as 0.224. The displacement limit load value (4,638 kN) can be obtained through a displacement limit experiment. With the friction coefficient considered, the theoretical load is 4,271 kN, which is relatively close to the experimental result. Thus, the friction coefficient exerts an influence on the displacement limit load P. The friction coefficient should be considered in the design analysis for HDS.

Friction coefficient and limiter load test analysis by flexibility coefficient model of Hold-Down Spring of nuclear reactor vessel internals

International Nuclear Information System (INIS)

Xie, Linjun

2017-01-01

The friction force between the contact surfaces of a reactor internal hold-down spring (HDS) and core barrel flanges can directly influence the axial stiffness of an HDS. However, friction coefficient cannot be obtained through theoretical analysis. This study performs a mathematical deduction of the physical model of an HDS. Moreover, a mathematical model of axial load P, displacement δ, and flexibility coefficient is established, and a set of test apparatuses is designed to simulate the preloading process of the HDS. According to the experimental research and theoretical analysis, P-δ curves and the flexibility coefficient λ are obtained in the loading processes of the HDS. The friction coefficient f of the M1000 HDS is further calculated as 0.224. The displacement limit load value (4,638 kN) can be obtained through a displacement limit experiment. With the friction coefficient considered, the theoretical load is 4,271 kN, which is relatively close to the experimental result. Thus, the friction coefficient exerts an influence on the displacement limit load P. The friction coefficient should be considered in the design analysis for HDS.

Tenth oil recovery conference

International Nuclear Information System (INIS)

Sleeper, R.

1993-01-01

The Tertiary Oil Recovery Project is sponsored by the State of Kansas to introduce Kansas producers to the economic potential of enhanced recovery methods for Kansas fields. Specific objectives include estimation of the state-wide tertiary oil resource, identification and evaluation of the most applicable processes, dissemination of technical information to producers, occasional collaboration on recovery projects, laboratory studies on Kansas applicable processes, and training of students and operators in tertiary oil recovery methods. Papers have been processed separately for inclusion on the data base

On High-Frequency Topography-Implied Gravity Signals for a Height System Unification Using GOCE-Based Global Geopotential Models

Science.gov (United States)

Grombein, Thomas; Seitz, Kurt; Heck, Bernhard

2017-03-01

National height reference systems have conventionally been linked to the local mean sea level, observed at individual tide gauges. Due to variations in the sea surface topography, the reference levels of these systems are inconsistent, causing height datum offsets of up to ±1-2 m. For the unification of height systems, a satellite-based method is presented that utilizes global geopotential models (GGMs) derived from ESA's satellite mission Gravity field and steady-state Ocean Circulation Explorer (GOCE). In this context, height datum offsets are estimated within a least squares adjustment by comparing the GGM information with measured GNSS/leveling data. While the GNSS/leveling data comprises the full spectral information, GOCE GGMs are restricted to long wavelengths according to the maximum degree of their spherical harmonic representation. To provide accurate height datum offsets, it is indispensable to account for the remaining signal above this maximum degree, known as the omission error of the GGM. Therefore, a combination of the GOCE information with the high-resolution Earth Gravitational Model 2008 (EGM2008) is performed. The main contribution of this paper is to analyze the benefit, when high-frequency topography-implied gravity signals are additionally used to reduce the remaining omission error of EGM2008. In terms of a spectral extension, a new method is proposed that does not rely on an assumed spectral consistency of topographic heights and implied gravity as is the case for the residual terrain modeling (RTM) technique. In the first step of this new approach, gravity forward modeling based on tesseroid mass bodies is performed according to the Rock-Water-Ice (RWI) approach. In a second step, the resulting full spectral RWI-based topographic potential values are reduced by the effect of the topographic gravity field model RWI_TOPO_2015, thus, removing the long to medium wavelengths. By using the latest GOCE GGMs, the impact of topography

Citizenship and recovery: two intertwined concepts for civic-recovery.

Science.gov (United States)

Pelletier, Jean-François; Corbière, Marc; Lecomte, Tania; Briand, Catherine; Corrigan, Patrick; Davidson, Larry; Rowe, Michael

2015-03-04

Validation of the psychometric properties of a new measure of citizenship was required for a research project in the province of Quebec, Canada. This study was meant to study the interplay between recovery- and citizenship-oriented supportive employment. As recovery and citizenship were expected to be two related concepts, convergent validity between the Citizenship Measure (CM) and the Recovery Assessment Scale (RAS) was tested. Study objectives were to: 1) conduct exploratory factor analyses on the CM and confirmatory factor analysis on the RAS tools (construct validity), 2) calculate Cronbach's alphas for each dimension emerging from objective 1 (reliability), and 3) calculate correlations between all dimensions from both tools (convergent validity). Data were collected from 174 individuals with serious mental illness, working in social firms. Serious mental illnesses include major depression, schizophrenia, bipolar disorder, obsessive compulsive disorder, panic disorder, post traumatic stress disorder and borderline personality disorder. Five factors emerged from the exploratory factor analysis of the CM, with good reliability. Confirmatory factor analyses showed that the short and the long versions of the RAS present satisfactory results. Finally, the correlation matrix indicated that all dimensions from both tools are significantly correlated, thus confirming their convergent validity. This study confirms the validity and reliability of two tools, CM and RAS. These tools can be used in combination to assess citizenship and recovery, both of which may be combined in the new concept of civic-recovery.

Multiphoton absorption coefficients in solids: an universal curve

International Nuclear Information System (INIS)

Brandi, H.S.; Araujo, C.B. de

1983-04-01

An universal curve for the frequency dependence of the multiphoton absorption coefficient is proposed based on a 'non-perturbative' approach. Specific applications have been made to obtain two, three, four and five photons absorption coefficient in different materials. Properly scaling of the two photon absorption coefficient and the use of the universal curve yields results for the higher order absorption coefficients in good agreement with the experimental data. (Author) [pt

Computational fluid dynamic (CFD) analysis on ALUDRA SR-10 UAV with parachute recovery system

Science.gov (United States)

Saim, R.; Mohd, S.; Shamsudin, S. S.; Zulkifli, M. F.; Omar, Z.; Subari@Rahmat, Z.; Masrom, M. F. Mohd; Zaki, Y.

2017-09-01

In an operation, belly landing is mostly applied as recovery method especially on research Unmanned Aerial Vehicle (UAV) such as Aludra SR-10. This type of landing method may encounter tough landing on hard soil and gravel which create high impact load on the aircraft. The impact may cause structural or system damage which costly to be repaired. Nowadays, Parachute Recovery System (PRS) recently used in numerous different tasks such as landing purpose to replace belly landing technique. Parachute use in this system to slow down flying or falling UAV to a safe landing by opening the canopy to increase aerodynamic drag. This paper was described the Computational Fluid Dynamic (CFD) analysis on ALUDRA SR-10 model with two different conditions i.e. the UAV equipped with and without parachute in order to identify the changes of aerodynamic characteristics. This simulation studies using solid models of aircraft and hemisphere parachute and was carried out by using ANSYS 16.0 Fluent under steady and turbulent flow and was modelled using the k-epsilon (k-ε) turbulence model. This simulation was limited to determine the drag force and drag coefficient. The obtained result showed that implementation of parachute increase 0.25 drag coefficient of the aircraft that is from 0.93 to 1.18. Subsequent to the reduction of descent rate caused by the parachute, the drag force of the aircraft increase by 0.76N. These increasing of drag force of the aircraft will produce lower terminal velocity which is expected to reduce the impact force on the aircraft during landing.

Drag coefficient Variability and Thermospheric models

Science.gov (United States)

Moe, Kenneth

Satellite drag coefficients depend upon a variety of factors: The shape of the satellite, its altitude, the eccentricity of its orbit, the temperature and mean molecular mass of the ambient atmosphere, and the time in the sunspot cycle. At altitudes where the mean free path of the atmospheric molecules is large compared to the dimensions of the satellite, the drag coefficients can be determined from the theory of free-molecule flow. The dependence on altitude is caused by the concentration of atomic oxygen which plays an important role by its ability to adsorb on the satellite surface and thereby affect the energy loss of molecules striking the surface. The eccentricity of the orbit determines the satellite velocity at perigee, and therefore the energy of the incident molecules relative to the energy of adsorption of atomic oxygen atoms on the surface. The temperature of the ambient atmosphere determines the extent to which the random thermal motion of the molecules influences the momentum transfer to the satellite. The time in the sunspot cycle affects the ambient temperature as well as the concentration of atomic oxygen at a particular altitude. Tables and graphs will be used to illustrate the variability of drag coefficients. Before there were any measurements of gas-surface interactions in orbit, Izakov and Cook independently made an excellent estimate that the drag coefficient of satellites of compact shape would be 2.2. That numerical value, independent of altitude, was used by Jacchia to construct his model from the early measurements of satellite drag. Consequently, there is an altitude dependent bias in the model. From the sparce orbital experiments that have been done, we know that the molecules which strike satellite surfaces rebound in a diffuse angular distribution with an energy loss given by the energy accommodation coefficient. As more evidence accumulates on the energy loss, more realistic drag coefficients are being calculated. These improved drag

Calculation of transport coefficients in an axisymmetric plasma

International Nuclear Information System (INIS)

Shumaker, D.E.

1977-01-01

A method of calculating the transport coefficient in an axisymmetric toroidal plasma is presented. This method is useful in calculating the transport coefficients in a Tokamak plasma confinement device. The particle density and temperature are shown to be a constant on a magnetic flux surface. Transport equations are given for the total particle flux and total energy flux crossing a closed toroidal surface. Also transport equations are given for the toroidal magnetic flux. A computer code was written to calculate the transport coefficients for a three species plasma, electrons and two species of ions. This is useful for calculating the transport coefficients of a plasma which contains impurities. It was found that the particle and energy transport coefficients are increased by a large amount, and the transport coefficients for the toroidal magnetic field are reduced by a small amount

Experimental methodology for obtaining sound absorption coefficients

Directory of Open Access Journals (Sweden)

Carlos A. Macía M

2011-07-01

Full Text Available Objective: the authors propose a new methodology for estimating sound absorption coefficients using genetic algorithms. Methodology: sound waves are generated and conducted along a rectangular silencer. The waves are then attenuated by the absorbing material covering the silencer’s walls. The attenuated sound pressure level is used in a genetic algorithm-based search to find the parameters of the proposed attenuation expressions that include geometric factors, the wavelength and the absorption coefficient. Results: a variety of adjusted mathematical models were found that make it possible to estimate the absorption coefficients based on the characteristics of a rectangular silencer used for measuring the attenuation of the noise that passes through it. Conclusions: this methodology makes it possible to obtain the absorption coefficients of new materials in a cheap and simple manner. Although these coefficients might be slightly different from those obtained through other methodologies, they provide solutions within the engineering accuracy ranges that are used for designing noise control systems.

LIMB-DARKENING COEFFICIENTS FOR ECLIPSING WHITE DWARFS

Energy Technology Data Exchange (ETDEWEB)

Gianninas, A.; Strickland, B. D.; Kilic, Mukremin [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks St., Norman, OK 73019 (United States); Bergeron, P., E-mail: alexg@nhn.ou.edu, E-mail: benstrickland@ou.edu, E-mail: kilic@ou.edu, E-mail: bergeron@astro.umontreal.ca [Departement de Physique, Universite de Montreal, C.P. 6128, Succ. Centre-Ville, Montreal, Quebec H3C 3J7 (Canada)

2013-03-20

We present extensive calculations of linear and nonlinear limb-darkening coefficients as well as complete intensity profiles appropriate for modeling the light-curves of eclipsing white dwarfs. We compute limb-darkening coefficients in the Johnson-Kron-Cousins UBVRI photometric system as well as the Large Synoptic Survey Telescope (LSST) ugrizy system using the most up to date model atmospheres available. In all, we provide the coefficients for seven different limb-darkening laws. We describe the variations of these coefficients as a function of the atmospheric parameters, including the effects of convection at low effective temperatures. Finally, we discuss the importance of having readily available limb-darkening coefficients in the context of present and future photometric surveys like the LSST, Palomar Transient Factory, and the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS). The LSST, for example, may find {approx}10{sup 5} eclipsing white dwarfs. The limb-darkening calculations presented here will be an essential part of the detailed analysis of all of these systems.

LIMB-DARKENING COEFFICIENTS FOR ECLIPSING WHITE DWARFS

International Nuclear Information System (INIS)

Gianninas, A.; Strickland, B. D.; Kilic, Mukremin; Bergeron, P.

2013-01-01

We present extensive calculations of linear and nonlinear limb-darkening coefficients as well as complete intensity profiles appropriate for modeling the light-curves of eclipsing white dwarfs. We compute limb-darkening coefficients in the Johnson-Kron-Cousins UBVRI photometric system as well as the Large Synoptic Survey Telescope (LSST) ugrizy system using the most up to date model atmospheres available. In all, we provide the coefficients for seven different limb-darkening laws. We describe the variations of these coefficients as a function of the atmospheric parameters, including the effects of convection at low effective temperatures. Finally, we discuss the importance of having readily available limb-darkening coefficients in the context of present and future photometric surveys like the LSST, Palomar Transient Factory, and the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS). The LSST, for example, may find ∼10 5 eclipsing white dwarfs. The limb-darkening calculations presented here will be an essential part of the detailed analysis of all of these systems.

Static pressure and temperature coefficients of working standard microphones

DEFF Research Database (Denmark)

Barrera Figueroa, Salvador; Cutanda Henriquez, Vicente; Torras Rosell, Antoni

2016-01-01

be a significant contribution to the uncertainty of the measurement. Determining the environmental coefficients of individual specimens of measurement microphones can be a straightforward though time-consuming procedure provided the appropriate facilities are available. An alternative is to determine them using...... coefficients. For this purpose, the environmental coefficients of some commercially available microphones have been determined experimentally, and whenever possible, compared with the coefficients determined numerically using the Boundary Element Method....... for these coefficients which are used for calibration purposes. Working standard microphones are not exempt of these influences. However, manufacturers usually provide a low frequency value of the environmental coefficient. While in some applications the influence of this coefficient may be negligible, in others it may...

Apparatus for measurement of coefficient of friction

Science.gov (United States)

Slifka, A. J.; Siegwarth, J. D.; Sparks, L. L.; Chaudhuri, Dilip K.

1990-01-01

An apparatus designed to measure the coefficient of friction in certain controlled atmospheres is described. The coefficient of friction observed during high-load tests was nearly constant, with an average value of 0.56. This value is in general agreement with that found in the literature and also with the initial friction coefficient value of 0.67 measured during self-mated friction of 440C steel in an oxygen environment.

New definition of the cell diffusion coefficient

International Nuclear Information System (INIS)

Koehler, P.

1975-01-01

As was shown in a recent work by Gelbard, the usually applied Benoist definition of the cell diffusion coefficient gives two different values if two different definitions of the cell are made. A new definition is proposed that preserves the neutron balance for the homogenized lattice and that is independent of the cell definition. The resulting diffusion coefficient is identical with the main term of Benoist's diffusion coefficient

Thyroglobulin recovery test of sera containing elevated levels of anti-thyroglobulin antibodies

International Nuclear Information System (INIS)

Hervas, I.; Gonzalez-Cabezas, P.; Flores, D.; Perez-Pastor, J.L.; Bello, P.; Rivas, A.; Alonso, J.; Olivas, C.; Mateo, A.

2002-01-01

Aim: Thyroglobulin (Tg) is a macro-molecule synthesized exclusively in the thyroid gland for the synthesis of thyroid hormones. In differentiated thyroid carcinoma, after radical thyroidectomy, the discovering of measurable quantities of Tg can be indicator of relapse y/or spread of disease but Thyroglobulin antibodies can alter the determination of Tg. The aim of this study is to assess and measure the interference of Tg antibodies on the Tg determination. Methods: We have selected 50 consecutive serum whose Tg-antibodies levels were higher than the normality values (0-100 UI/mL). Tg-antibodies were measured using a 'sandwich' radioimmunometric assay on solid phase. We have performed a recovery test on these sera. This test consists on adding a known quantity (50 UI) of Tg on that sera and then measure the Tg values to find out the percentage of Tg that is recuperated. Tg was measured using a radioimmunometric assay on solid phase. Results: Sera were divided in two groups: A.- 15 sera with Tg-antibodies levels between 100-250 UI/mL: 85% of them presented a Tg recovery percentage higher than 90% (Tg-antibodies did not interfere on Tg values due to Tg was recovered almost in its totality). B.- 53 sera with Tg-antibodies levels higher than 250 UI/mL: Only 10% of them presented a Tg recovery percentage higher than >90% . (90% of sera interfered on Tg values). 70% of that sera presented percentages under 50%. The Pearson's correlation coefficient between Tg-antibodies and Tg recovery percentage was -0.34. Conclusions: The majority (90%)of sera with Tg-antibodies higher than 250 UI/mL presented an high interference on Tg determination. However the majority of sera with Tg-antibodies between 100-250 did not show any interference on Tg determination. There are not linear correlation between highest values and lowest percentages of Tg recovered. We recommend the realization of Tg recovery test on sera with elevated Tg antibodies specially when are higher than 250 UI/mL

A new proposal for Lagrangian correlation coefficient

International Nuclear Information System (INIS)

Altinsoy, N.; Tugrul, A.B.

2002-01-01

The statistical description of dispersion in turbulent flow was first considered by Taylor (Proc. London Math. Soc. 20 (1921) 196) and the statistical properties of the field were determined by Lagrangian correlation coefficient R L (τ). Frenkiel (Adv. Appl. Mech. 3 (1953) 61) has proposed several simple forms for R L (τ). Some workers have investigated for a proper form of the Lagrangian correlation coefficient. In this work, a new proposal for the Lagrangian correlation coefficient is proposed and discussed. It can be written in general form with the one of the Frenkiel's (Adv. Appl. Mech. 3 (1953) 61) Lagrangian correlation coefficient. There is very satisfactory agreement between the new correlation and the experiment

Fuel Temperature Coefficient of Reactivity

Energy Technology Data Exchange (ETDEWEB)

Loewe, W.E.

2001-07-31

A method for measuring the fuel temperature coefficient of reactivity in a heterogeneous nuclear reactor is presented. The method, which is used during normal operation, requires that calibrated control rods be oscillated in a special way at a high reactor power level. The value of the fuel temperature coefficient of reactivity is found from the measured flux responses to these oscillations. Application of the method in a Savannah River reactor charged with natural uranium is discussed.

Virial Coefficients for the Liquid Argon

Science.gov (United States)

Korth, Micheal; Kim, Saesun

2014-03-01

We begin with a geometric model of hard colliding spheres and calculate probability densities in an iterative sequence of calculations that lead to the pair correlation function. The model is based on a kinetic theory approach developed by Shinomoto, to which we added an interatomic potential for argon based on the model from Aziz. From values of the pair correlation function at various values of density, we were able to find viral coefficients of liquid argon. The low order coefficients are in good agreement with theoretical hard sphere coefficients, but appropriate data for argon to which these results might be compared is difficult to find.

Problems with Discontinuous Diffusion/Dispersion Coefficients

Directory of Open Access Journals (Sweden)

Stefano Ferraris

2012-01-01

accurate on smooth solutions and based on a special numerical treatment of the diffusion/dispersion coefficients that makes its application possible also when such coefficients are discontinuous. Numerical experiments confirm the convergence of the numerical approximation and show a good behavior on a set of benchmark problems in two space dimensions.

Modified Regression Correlation Coefficient for Poisson Regression Model

Science.gov (United States)

Kaengthong, Nattacha; Domthong, Uthumporn

2017-09-01

This study gives attention to indicators in predictive power of the Generalized Linear Model (GLM) which are widely used; however, often having some restrictions. We are interested in regression correlation coefficient for a Poisson regression model. This is a measure of predictive power, and defined by the relationship between the dependent variable (Y) and the expected value of the dependent variable given the independent variables [E(Y|X)] for the Poisson regression model. The dependent variable is distributed as Poisson. The purpose of this research was modifying regression correlation coefficient for Poisson regression model. We also compare the proposed modified regression correlation coefficient with the traditional regression correlation coefficient in the case of two or more independent variables, and having multicollinearity in independent variables. The result shows that the proposed regression correlation coefficient is better than the traditional regression correlation coefficient based on Bias and the Root Mean Square Error (RMSE).

Life cycle water demand coefficients for crude oil production from five North American locations.

Science.gov (United States)

Ali, Babkir; Kumar, Amit

2017-10-15

The production of liquid fuels from crude oil requires water. There has been limited focus on the assessment of life cycle water demand footprints for crude oil production and refining. The overall aim of this paper is address this gap. The objective of this research is to develop water demand coefficients over the life cycle of fuels produced from crude oil pathways. Five crude oil fields were selected in the three North American countries to reflect the impact of different spatial locations and technologies on water demand. These include the Alaska North Slope, California's Kern County heavy oil, and Mars in the U.S.; Maya in Mexico; and Bow River heavy oil in Alberta, Canada. A boundary for an assessment of the life cycle water footprint was set to cover the unit operations related to exploration, drilling, extraction, and refining. The recovery technology used to extract crude oil is one of the key determining factors for water demand. The amount of produced water that is re-injected to recover the oil is essential in determining the amount of fresh water that will be required. During the complete life cycle of one barrel of conventional crude oil, 1.71-8.25 barrels of fresh water are consumed and 2.4-9.51 barrels of fresh water are withdrawn. The lowest coefficients are for Bow River heavy oil and the highest coefficients are for Maya crude oil. Of all the unit operations, exploration and drilling require the least fresh water (less than 0.015 barrel of water per barrel of oil produced). A sensitivity analysis was conducted and uncertainty in the estimates was determined. Copyright © 2017 Elsevier Ltd. All rights reserved.

Temporal correlation coefficient for directed networks.

Science.gov (United States)

Büttner, Kathrin; Salau, Jennifer; Krieter, Joachim

2016-01-01

Previous studies dealing with network theory focused mainly on the static aggregation of edges over specific time window lengths. Thus, most of the dynamic information gets lost. To assess the quality of such a static aggregation the temporal correlation coefficient can be calculated. It measures the overall possibility for an edge to persist between two consecutive snapshots. Up to now, this measure is only defined for undirected networks. Therefore, we introduce the adaption of the temporal correlation coefficient to directed networks. This new methodology enables the distinction between ingoing and outgoing edges. Besides a small example network presenting the single calculation steps, we also calculated the proposed measurements for a real pig trade network to emphasize the importance of considering the edge direction. The farm types at the beginning of the pork supply chain showed clearly higher values for the outgoing temporal correlation coefficient compared to the farm types at the end of the pork supply chain. These farm types showed higher values for the ingoing temporal correlation coefficient. The temporal correlation coefficient is a valuable tool to understand the structural dynamics of these systems, as it assesses the consistency of the edge configuration. The adaption of this measure for directed networks may help to preserve meaningful additional information about the investigated network that might get lost if the edge directions are ignored.

Kubo Formulas for Second-Order Hydrodynamic Coefficients

International Nuclear Information System (INIS)

Moore, Guy D.; Sohrabi, Kiyoumars A.

2011-01-01

At second order in gradients, conformal relativistic hydrodynamics depends on the viscosity η and on five additional ''second-order'' hydrodynamical coefficients τ Π , κ, λ 1 , λ 2 , and λ 3 . We derive Kubo relations for these coefficients, relating them to equilibrium, fully retarded three-point correlation functions of the stress tensor. We show that the coefficient λ 3 can be evaluated directly by Euclidean means and does not in general vanish.

Irrational "Coefficients" in Renaissance Algebra.

Science.gov (United States)

Oaks, Jeffrey A

2017-06-01

Argument From the time of al-Khwārizmī in the ninth century to the beginning of the sixteenth century algebraists did not allow irrational numbers to serve as coefficients. To multiply by x, for instance, the result was expressed as the rhetorical equivalent of . The reason for this practice has to do with the premodern concept of a monomial. The coefficient, or "number," of a term was thought of as how many of that term are present, and not as the scalar multiple that we work with today. Then, in sixteenth-century Europe, a few algebraists began to allow for irrational coefficients in their notation. Christoff Rudolff (1525) was the first to admit them in special cases, and subsequently they appear more liberally in Cardano (1539), Scheubel (1550), Bombelli (1572), and others, though most algebraists continued to ban them. We survey this development by examining the texts that show irrational coefficients and those that argue against them. We show that the debate took place entirely in the conceptual context of premodern, "cossic" algebra, and persisted in the sixteenth century independent of the development of the new algebra of Viète, Decartes, and Fermat. This was a formal innovation violating prevailing concepts that we propose could only be introduced because of the growing autonomy of notation from rhetorical text.

Regional radiation dose susceptibility within the parotid gland: Effects on salivary loss and recovery

Energy Technology Data Exchange (ETDEWEB)

Clark, Haley, E-mail: hdclark@phas.ubc.ca; Reinsberg, Stefan [Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1 (Canada); Hovan, Allan [Oral Oncology/Dentistry, British Columbia Cancer Agency–Vancouver Centre, Vancouver, British Columbia V5Z 4E6 (Canada); Moiseenko, Vitali [Department of Radiation Medicine and Applied Sciences, University of California–San Diego, La Jolla, California 92093 (United States); Thomas, Steven [Department of Medical Physics, British Columbia Cancer Agency–Vancouver Centre, Vancouver, British Columbia V5Z 4E6 (Canada); Wu, Jonn [Radiation Oncology, British Columbia Cancer Agency–Vancouver Centre, Vancouver, British Columbia V5Z 4E6 (Canada)

2015-04-15

Purpose: Xerostomia is one of the most likely late toxic effects of radiotherapy treatment in patients with head-and-neck cancers. Modern treatment techniques can incorporate knowledge of complication risk into treatment plans. To this end, the authors attempt to quantify the regional radiotherapy dose-dependence of salivary output loss and recovery in a prospective study. Methods: Salivary output was collected from patients undergoing radiotherapy treatment for head-and-neck cancers at the BC Cancer Agency between February 2008 and May 2013. Regional dose-dependence (i.e., dose susceptibility) of loss and recovery is quantified using nonparametric (Spearman’s rank correlation coefficients, local linear regression) and parametric (least-sum of squares, least-median of squares) techniques. Results: Salivary flow recovery was seen in 79 of 102 patients considered (p < 0.0001, Wilcoxon sign rank test). Output loss was strongly correlated with left- and right parotid combined dose φ = min (D{sub L},  45 Gy) + min (D{sub R},  45 Gy), and can be accurately predicted. Median early loss (three months) was 72% of baseline, while median overall loss (1 yr) was 56% of baseline. Fitting an exponential model to whole parotid yields dose sensitivities A{sub 3m} = 0.0604 Gy{sup −1} and A{sub 1y} = 0.0379 Gy{sup −1}. Recovery was not significantly associated with dose. Hints of lateral organ sub-segment dose–response dimorphism were observed. Conclusions: Sub-segmentation appears to predict neither loss nor recovery with any greater precision than whole parotid mean dose, though it is not any worse. Sparing the parotid to a combined dose φ of <50 Gy is recommended for a patient to keep ≈40% of baseline function and thus avoid severe xerostomia at 12 months post-treatment. It seems unlikely that a population’s mean recovery will exceed 20%–30% of baseline output at 1 yr after radiotherapy treatment using current (whole-organ based) clinical guidelines.

Umbilical Cable Recovery Load Analysis

Institute of Scientific and Technical Information of China (English)

YAN Shu-wang; JIA Zhao-lin; FENG Xiao-wei; LI Shi-tao

2013-01-01

Umbilical cable is a kind of integrated subsea cable widely used in the exploration and exploitation of oil and gas field.The severe ocean environment makes great challenges to umbilical maintenance and repair work.Damaged umbilical is usually recovered for the regular operation of the offshore production system.Analysis on cables in essence is a two-point boundary problem.The tension load at the mudline must be known first,and then the recovery load and recovery angle on the vessel can be solved by use of catenary equation.The recovery analysis also involves umbilicalsoil interaction and becomes more complicated.Calculation methods for recovery load of the exposed and buried umbilical are established and the relationship between the position of touch down point and the recovery load as well as the recovery angle and recovery load are analyzed.The analysis results provide a theoretical reference for offshore on-deck operation.

Activity coefficients of electrons and holes in semiconductors

International Nuclear Information System (INIS)

Orazem, M.E.; Newman, J.

1984-01-01

Dilute-solution transport equations with constant activity coefficients are commonly used to model semiconductors. These equations are consistent with a Boltzmann distribution and are invalid in regions where the species concentration is close to the respective site concentration. A more rigorous treatment of transport in a semiconductor requires activity coefficients which are functions of concentration. Expressions are presented for activity coefficients of electrons and holes in semiconductors for which conduction- and valence-band energy levels are given by the respective bandedge energy levels. These activity coefficients are functions of concentration and are thermodynamically consistent. The use of activity coefficients in macroscopic transport relationships allows a description of electron transport in a manner consistent with the Fermi-Dirac distribution

Extracting electron backscattering coefficients from backscattered electron micrographs

International Nuclear Information System (INIS)

Zupanic, F.

2010-01-01

Electron backscattering micrographs possess the so-called Z-contrast, carrying information about the chemical compositions of phases present in microstructures. The intensity at a particular point in the backscattered electron micrograph is proportional to the signal detected at a corresponding point in the scan raster, which is, in turn, proportional to the electron backscattering coefficient of a phase at that point. This article introduces a simple method for extracting the electron backscattering coefficients of phases present in the microstructure, from the backscattered electron micrographs. This method is able to convert the micrograph's greyscale to the backscattering-coefficient-scale. The prerequisite involves the known backscattering coefficients for two phases in the micrograph. In this way, backscattering coefficients of other phases can be determined. The method is unable to determine the chemical compositions of phases or the presence of an element only from analysing the backscattered electron micrograph. Nevertheless, this method was found to be very powerful when combined with energy dispersive spectroscopy, and the calculations of backscattering coefficients. - Research Highlights: →A simple method for extracting the electron backscattering coefficients →The prerequisite is known backscattering coefficients for two phases →The information is complementary to the EDS-results. →This method is especially useful when a phase contains a light element (H, Li, Be, and B)

Attenuation coefficients of soils

International Nuclear Information System (INIS)

Martini, E.; Naziry, M.J.

1989-01-01

As a prerequisite to the interpretation of gamma-spectrometric in situ measurements of activity concentrations of soil radionuclides the attenuation of 60 to 1332 keV gamma radiation by soil samples varying in water content and density has been investigated. A useful empirical equation could be set up to describe the dependence of the mass attenuation coefficient upon photon energy for soil with a mean water content of 10%, with the results comparing well with data in the literature. The mean density of soil in the GDR was estimated at 1.6 g/cm 3 . This value was used to derive the linear attenuation coefficients, their range of variation being 10%. 7 figs., 5 tabs. (author)

Anomaly coefficients: Their calculation and congruences

International Nuclear Information System (INIS)

Braden, H.W.

1988-01-01

A new method for the calculation of anomaly coefficients is presented. For su(n) some explicit and general expressions are given for these. In particular, certain congruences are discovered and investigated among the leading anomaly coefficients. As an application of these congruences, the absence of global six-dimensional gauge anomalies is shown

A new consistent definition of the homogenized diffusion coefficient of a lattice, limitations of the homogenization concept, and discussion of previously defined coefficients

International Nuclear Information System (INIS)

Deniz, V.C.

1978-01-01

The problem concerned with the correct definition of the homogenized diffusion coefficient of a lattice, and the concurrent problem of whether or not a homogenized diffusion equation can be formally set up, is studied by a space-energy angle dependent treatment for a general lattice cell; using an operator notation which applies to any eigen-problem. It is shown that the diffusion coefficient should represent only leakage effects. A new definition of the diffusion coefficient is given, which combines within itself the individual merits of each of the two definitions of Benoist, and reduces to the 'uncorrected' Benoist coefficient in certain cases. The conditions under which a homogenized diffusion equation can be obtained are discussed. A compatison is made between the approach via a diffusion equation and the approach via the eigen-coefficients of Deniz. Previously defined diffusion coefficients are discussed, and it is shown that the transformed eigen-coefficients proposed by Gelbard and by Larsen are unsuitable as diffusion coefficients, and that the cell-edge normalization of the Bonalumi coefficient is not physically justifiable. (author)

Digital recovery management: Characterizing recovery-specific social network site participation and perceived benefit.

Science.gov (United States)

Bergman, Brandon G; Kelly, Nathaniel W; Hoeppner, Bettina B; Vilsaint, Corrie L; Kelly, John F

2017-06-01

Research shows that digital social network sites (SNSs) may be valuable platforms to effect health behavior change. Little is known specifically about their ability to help address alcohol and other drug problems. This gap is noteworthy, given that individuals are already participating in existing, recovery-specific SNSs (hereafter referred to as recovery SNSs): online communities with the functionality of conventional SNSs (e.g., Facebook) that focus on substance use disorder (SUD) recovery. For example, InTheRooms.com (ITR) is a large, well-known recovery SNS that is available for free 24 hr/day via website and mobile smartphone applications. It offers recovery tools within a digital social milieu for over 430,000 registered users. To augment the knowledge base on recovery SNS platforms, we conducted an online survey of 123 ITR participants (M = 50.8 years old; 56.9% female; 93.5% White; M = 7.3 years of abstinence, range of 0-30 years; 65% cited alcohol as their primary substance). Respondents engaged with ITR, on average, for about 30 min/day several times each week. Daily meditation prompts and live online video meetings were the most commonly utilized resources. Participants generally endorsed ITR as a helpful platform, particularly with respect to increased abstinence/recovery motivation and self-efficacy. Compared to individuals abstinent for 1 or more years, those abstinent less than 1 year (including nonabstinent individuals) showed similar rates of engagement with ITR activities and similar levels of perceived benefit. Our findings suggest that longitudinal studies are warranted to examine the clinical utility of ITR and other recovery SNSs as SUD treatment adjuncts and/or recovery self-management tools. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Probability based calibration of pressure coefficients

DEFF Research Database (Denmark)

Hansen, Svend Ole; Pedersen, Marie Louise; Sørensen, John Dalsgaard

2015-01-01

Normally, a consistent basis for calculating partial factors focuses on a homogeneous reliability index neither depending on which material the structure is constructed of nor the ratio between the permanent and variable actions acting on the structure. Furthermore, the reliability index should n...... the characteristic shape coefficients are based on mean values as specified in background documents to the Eurocodes. Importance of hidden safeties judging the reliability is discussed for wind actions on low-rise structures....... not depend on the type of variable action. A probability based calibration of pressure coefficients have been carried out using pressure measurements on the standard CAARC building modelled on scale of 1:383. The extreme pressures measured on the CAARC building model in the wind tunnel have been fitted.......3, the Eurocode partial factor of 1.5 for variable actions agrees well with the inherent uncertainties of wind actions when the pressure coefficients are determined using wind tunnel test results. The increased bias and uncertainty when pressure coefficients mainly are based on structural codes lead to a larger...

Role of self-efficacy and social support in short-term recovery after total hip replacement: a prospective cohort study.

Science.gov (United States)

Brembo, Espen Andreas; Kapstad, Heidi; Van Dulmen, Sandra; Eide, Hilde

2017-04-11

Despite the overall success of total hip replacement (THR) in patients with symptomatic osteoarthritis (OA), up to one-quarter of patients report suboptimal recovery. The aim of this study was to determine whether social support and general self-efficacy predict variability in short-term recovery in a Norwegian cohort. We performed secondary analysis of a prospective multicenter study of 223 patients who underwent THR for OA in 2003-2004. The total score of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) at 3 months after surgery was used as the recovery variable. We measured self-efficacy using the General Self-Efficacy Scale (GSES) and social support with the Social Provisions Scale (SPS). Preoperative and postoperative scores were compared using Wilcoxon tests. The Mann-Whitney U test compared scores between groups that differed in gender and age. Spearman's rho correlation coefficients were used to evaluate associations between selected predictor variables and the recovery variable. We performed univariate and multiple linear regression analyses to identify independent variables and their ability to predict short-term recovery after THR. The median preoperative WOMAC score was 58.3 before and 23.9 after surgery. The mean absolute change was 31.9 (standard deviation [SD] 17.0) and the mean relative change was 54.8% (SD 26.6). Older age, female gender, higher educational level, number of comorbidities, baseline WOMAC score, self-efficacy, and three of six individual provisions correlated significantly with short-term recovery after THR and predicted the variability in recovery in the univariate regression model. In multiple regression models, baseline WOMAC was the most consistent predictor of short-term recovery: a higher preoperative WOMAC score predicted worse short-term recovery (β = 0.44 [0.29, 0.59]). Higher self-efficacy predicted better recovery (β = -0.44 [-0.87, -0.02]). Reliable alliance was a significant predictor

Axially symmetric reconstruction of plasma emission and absorption coefficients

International Nuclear Information System (INIS)

Yang Lixin; Jia Hui; Yang Jiankun; Li Xiujian; Chen Shaorong; Liu Xishun

2013-01-01

A layered structure imaging model is developed in order to reconstruct emission coefficients and absorption coefficients simultaneously, in laser fusion core plasma diagnostics. A novel axially symmetric reconstruction method that utilizes the LM (Levenberg-Marquardt) nonlinear least squares minimization algorithm is proposed based on the layered structure. Numerical simulation results demonstrate that the proposed method is sufficiently accurate to reconstruct emission coefficients and absorption coefficients, and when the standard deviation of noise is 0.01, the errors of emission coefficients and absorption coefficients are 0.17, 0.22, respectively. Furthermore, this method could perform much better on reconstruction effect compared with traditional inverse Abel transform algorithms. (authors)

Estimating Runoff Coefficients Using Weather Radars

DEFF Research Database (Denmark)

Ahm, Malte; Thorndahl, Søren Liedtke; Rasmussen, Michael R.

2012-01-01

This paper presents a method for estimating runoff coefficients of urban drainage catchments based on a combination of high resolution weather radar data and insewer flow measurements. By utilising the spatial variability of the precipitation it is possible to estimate the runoff coefficients...... of separate subcatchments. The method is demonstrated through a case study of an urban drainage catchment (678ha) located in the municipality of Aarhus, Denmark. The study has proven it is possible to use corresponding measurements of the relative rainfall distribution over the catchment and runoff...... measurements to identify the runoff coefficients at subcatchment level. The number of potential subcatchments is limited by the number of available rainfall events with a sufficient spatial variability....

Disaster recovery using VMware vSphere Replication and vCenter Site Recovery Manager

CERN Document Server

GB, Abhilash

2014-01-01

This is a step-by-step guide that will help you understand disaster recovery using VMware vSphere Replication 5.5 and VMware vCenter Site Recovery Manager (SRM) 5.5. The topics and configuration procedures are accompanied with relevant screenshots, flowcharts, and logical diagrams that makes grasping the concepts easier. This book is a guide for anyone who is keen on using vSphere Replication or vCenter Site Recovery Manager as a disaster recovery solution. This is an excellent handbook for solution architects, administrators, on-field engineers, and support professionals. Although the book as

Diffusion coefficient adaptive correction in Lagrangian puff model

International Nuclear Information System (INIS)

Tan Wenji; Wang Dezhong; Ma Yuanwei; Ji Zhilong

2014-01-01

Lagrangian puff model is widely used in the decision support system for nuclear emergency management. The diffusion coefficient is one of the key parameters impacting puff model. An adaptive method was proposed in this paper, which could correct the diffusion coefficient in Lagrangian puff model, and it aimed to improve the accuracy of calculating the nuclide concentration distribution. This method used detected concentration data, meteorological data and source release data to estimate the actual diffusion coefficient with least square method. The diffusion coefficient adaptive correction method was evaluated by Kincaid data in MVK, and was compared with traditional Pasquill-Gifford (P-G) diffusion scheme method. The results indicate that this diffusion coefficient adaptive correction method can improve the accuracy of Lagrangian puff model. (authors)

Taylor coefficients and coefficient multipliers of Hardy and Bergman-type spaces

CERN Document Server

Jevtić, Miroljub; Arsenović, Miloš

2016-01-01

This book provides a systematic overview of the theory of Taylor coefficients of functions in some classical spaces of analytic functions and especially of the coefficient multipliers between spaces of Hardy type. Offering a comprehensive reference guide to the subject, it is the first of its kind in this area. After several introductory chapters covering the basic material, a large variety of results obtained over the past 80 years, including the most recent ones, are treated in detail. Several chapters end with discussions of practical applications and related topics that graduate students and experts in other subjects may find useful for their own purposes. Thus, a further aim of the book is to communicate to non-specialists some concrete facts that may be of value in their own work. The book can also be used as a textbook or a supplementary reference for an advanced graduate course. It is primarily intended for specialists in complex and functional analysis, graduate students, and experts in other related...

Roughness coefficient and its uncertainty in gravel-bed river

Directory of Open Access Journals (Sweden)

Ji-Sung Kim

2010-06-01

Full Text Available Manning's roughness coefficient was estimated for a gravel-bed river reach using field measurements of water level and discharge, and the applicability of various methods used for estimation of the roughness coefficient was evaluated. Results show that the roughness coefficient tends to decrease with increasing discharge and water depth, and over a certain range it appears to remain constant. Comparison of roughness coefficients calculated by field measurement data with those estimated by other methods shows that, although the field-measured values provide approximate roughness coefficients for relatively large discharge, there seems to be rather high uncertainty due to the difference in resultant values. For this reason, uncertainty related to the roughness coefficient was analyzed in terms of change in computed variables. On average, a 20% increase of the roughness coefficient causes a 7% increase in the water depth and an 8% decrease in velocity, but there may be about a 15% increase in the water depth and an equivalent decrease in velocity for certain cross-sections in the study reach. Finally, the validity of estimated roughness coefficient based on field measurements was examined. A 10% error in discharge measurement may lead to more than 10% uncertainty in roughness coefficient estimation, but corresponding uncertainty in computed water depth and velocity is reduced to approximately 5%. Conversely, the necessity for roughness coefficient estimation by field measurement is confirmed.

Assessing the additional impact of Process Recovery Communications on Customer Outcomes: A Comprehensive Service Recovery Approach

OpenAIRE

Y. VAN VAERENBERGH; B. LARIVIÈRE; I. VERMEIR

2009-01-01

Purpose – Services recoveries following service failures not only imply customer recovery opportunities in which customer-company relationships can be restored, they can also result in process improvements (i.e. process recoveries in literature). This paper seeks to identify the additional impact of process recoveries on four customer outcome variables (satisfaction with service recovery, overall satisfaction, repurchase intent and word-of-mouth) by communicating these improvements back to th...

A gain-coefficient switched Alexandrite laser

International Nuclear Information System (INIS)

Lee, Chris J; Van der Slot, Peter J M; Boller, Klaus-J

2013-01-01

We report on a gain-coefficient switched Alexandrite laser. An electro-optic modulator is used to switch between high and low gain states by making use of the polarization dependent gain of Alexandrite. In gain-coefficient switched mode, the laser produces 85 ns pulses with a pulse energy of 240 mJ at a repetition rate of 5 Hz.

the dutch crisis and recovery act: economic recovery and legal crisis

African Journals Online (AJOL)

Jonathan

THE DUTCH CRISIS AND RECOVERY ACT: ECONOMIC RECOVERY AND. LEGAL CRISIS? J Verschuuren. 1 Introduction. Throughout the world, governments are responding to the financial and economic crisis. Such responses vary from supporting the banking system to adopting economic stimulus packages. The latter ...

Quantum Non-Markovian Langevin Equations and Transport Coefficients

International Nuclear Information System (INIS)

Sargsyan, V.V.; Antonenko, N.V.; Kanokov, Z.; Adamian, G.G.

2005-01-01

Quantum diffusion equations featuring explicitly time-dependent transport coefficients are derived from generalized non-Markovian Langevin equations. Generalized fluctuation-dissipation relations and analytic expressions for calculating the friction and diffusion coefficients in nuclear processes are obtained. The asymptotic behavior of the transport coefficients and correlation functions for a damped harmonic oscillator that is linearly coupled in momentum to a heat bath is studied. The coupling to a heat bath in momentum is responsible for the appearance of the diffusion coefficient in coordinate. The problem of regression of correlations in quantum dissipative systems is analyzed

Roughness coefficients for stream channels in Arizona

Science.gov (United States)

Aldridge, B.N.; Garrett, J.M.

1973-01-01

When water flows in an open channel, energy is lost through friction along the banks and bed of the channel and through turbulence within the channel. The amount of energy lost is governed by channel roughness, which is expressed in terms of a roughness coefficient. An evaluation of the roughness coefficient is necessary in many hydraulic computations that involve flow in an open channel. Owing to the lack of satisfactory quantitative procedure, the ability of evaluate roughness coefficients can be developed only through experience; however, a basic knowledge of the methods used to assign the coefficients and the factors affecting them will be a great help. One of the most commonly used equations in open-channel hydraulics is that of Manning. The Manning equation is       1.486

Is high recovery more effective than expected recovery in addressing service failure? - a moral judgment perspective

OpenAIRE

Chen, Tong; Ma, Ke; Bian, Xuemei; Zheng, Chundong; Devlin, James

2018-01-01

In the context of two distinctive consumer categories and two different product settings, this research examines the effects of recovery on recovery performance as a function of consumer moral judgment of service failure. The findings of two studies reveal that consumers' response to recovery anchors on the magnitude of recovery but these responses are adjusted according to consumers' moral judgment of service failure. Specifically, consumers react more positively toward expected recovery tha...

Heat conduction coefficient and coefficient of linear thermal expansion of electric insulation materials for superconducting magnetic system

International Nuclear Information System (INIS)

Deev, V.I.; Sobolev, V.P.; Kruglov, A.B.; Pridantsev, A.I.

1984-01-01

Results of experimental investigation of heat conduction coefficient and coefficient of linear thermal expansion and thermal shrinkages of the STEF-1 textolite-glass widely used in superconducting magnetic systems as electric insulating and structural material are presented. Samples of two types have been died: sample axisa is perpendicular to a plae of fiberglass layers ad sample axis is parallel to a plane of fiberglass layers. Heat conduction coefficient was decreased almost a five times with temperature decrease from 300 up to 5K and was slightly dependent on a sample type. Temperature variation of linear dimensions in a sample of the first type occurs in twice as fast as compared to the sample of the second type

Maximization of energy recovery inside supersonic separator in the presence of condensation and normal shock wave

International Nuclear Information System (INIS)

Shooshtari, S.H. Rajaee; Shahsavand, A.

2017-01-01

Natural gases provide around a quarter of energy consumptions around the globe. Supersonic separators (3S) play multifaceted role in natural gas industry processing, especially for water and hydrocarbon dew point corrections. These states of the art devices have minimum energy requirement and favorable process economy compared to conventional facilities. Their relatively large pressure drops may limit their application in some situations. To maximize the energy recovery of the dew point correction facility, the pressure loss across the 3S unit should be minimized. The optimal structure of 3s unit (including shock wave location and diffuser angle) is selected using simultaneous combination of normal shock occurrence and condensation in the presence of nucleation and growth processes. The condense-free gas enters the non-isentropic normal shock wave. The simulation results indicate that the normal shock location, pressure recovery coefficient and onset position strongly vary up to a certain diffuser angle (β = 8°) with the maximum pressure recovery of 0.88 which leads to minimum potential energy loss. Computational fluid dynamic simulations show that separation of boundary layer does not happen for the computed optimal value of β and it is essentially constant when the inlet gas temperatures and pressures vary over a relatively broad range. - Highlights: • Supersonic separators have found numerous applications in oil and gas industries. • Maximum pressure recovery is crucial for such units to maximize energy efficiency. • Simultaneous condensation and shock wave occurrence are studied for the first time. • Diverging nozzle angle of 8° can provide maximum pressure recovery of 0.88. • The optimal diffuser angle remains constant over a broad range of inlet conditions.

Breakdown coefficients and scaling properties of rain fields

Directory of Open Access Journals (Sweden)

D. Harris

1998-01-01

Full Text Available The theory of scale similarity and breakdown coefficients is applied here to intermittent rainfall data consisting of time series and spatial rain fields. The probability distributions (pdf of the logarithm of the breakdown coefficients are the principal descriptor used. Rain fields are distinguished as being either multiscaling or multiaffine depending on whether the pdfs of breakdown coefficients are scale similar or scale dependent, respectively. Parameter  estimation techniques are developed which are applicable to both multiscaling and multiaffine fields. The scale parameter (width, σ, of the pdfs of the log-breakdown coefficients is a measure of the intermittency of a field. For multiaffine fields, this scale parameter is found to increase with scale in a power-law fashion consistent with a bounded-cascade picture of rainfall modelling. The resulting power-law exponent, H, is indicative of the smoothness of the field. Some details of breakdown coefficient analysis are addressed and a theoretical link between this analysis and moment scaling analysis is also presented. Breakdown coefficient properties of cascades are also investigated in the context of parameter estimation for modelling purposes.

Recovery Spirituality

Directory of Open Access Journals (Sweden)

Ernest Kurtz

2015-01-01

Full Text Available There is growing interest in Alcoholics Anonymous (A.A. and other secular, spiritual, and religious frameworks of long-term addiction recovery. The present paper explores the varieties of spiritual experience within A.A., with particular reference to the growth of a wing of recovery spirituality promoted within A.A. It is suggested that the essence of secular spirituality is reflected in the experience of beyond (horizontal and vertical transcendence and between (connection and mutuality and in six facets of spirituality (Release, Gratitude, Humility, Tolerance, Forgiveness, and a Sense of Being-at-home shared across religious, spiritual, and secular pathways of addiction recovery. The growing varieties of A.A. spirituality (spanning the “Christianizers” and “Seculizers” reflect A.A.’s adaptation to the larger diversification of religious experience and the growing secularization of spirituality across the cultural contexts within which A.A. is nested.

Vehicle recovery and towing guideline

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-01-15

This guideline was developed to provide light and medium duty vehicles operators in the oil and gas industry with a set of best practices for avoiding injury and damage during the recovery of stuck vehicles. The aim of the guideline was to increase awareness of safety issues and promote the safe usage of the vehicles by personnel throughout the petroleum industry and to establish minimum standards of practice for vehicle recovery. The guideline included a step-by-step guide for pulling out a vehicle with a recovery strap as well as vehicle-mounted winch procedures. Pre-job checklists for both procedures were provided. Issues related to the strength rating of vehicle tow hooks and hitch receivers were discussed, as well as some of the hazards associated with steep terrains and heavy mud. The guideline also included recommendations for a vehicle recovery kit with instructions on vehicle recovery, a recovery strap, a recovery hitch and shackle, a collapsible shovel, traffic cones and reflector flares, and a heavy blanket and gloves. 7 refs., 2 tabs., 13 figs.

Recovery from a psychiatrist's viewpoint.

Science.gov (United States)

Diamond, Ronald J

2006-09-01

Recovery is not the same as cure. Recovery from mental illness is the process of having more to life than just illness. It is an ongoing process rather than simply a goal that can be achieved. Recovery from the stigma of mental illness may be as difficult as recovery from the illness itself. Several common, but incorrect, beliefs can interfere with the recovery process. Myths include the belief that the illness has an inherently downhill course, that rehabilitation is useful only after stabilization, and that people with schizophrenia can only work at low-level jobs. People who have schizophrenia have reported that their own process of recovery was helped by their determination to get better, an understanding of the illness, taking personal responsibility, having friends who accept them, an optimistic attitude, and spiritual beliefs that help them find meaning in life.

Houston Recovery Initiative: A Rich Case Study of Building Recovery Communities One Voice at a Time.

Science.gov (United States)

Bitting, Sara; Nash, Angela; Ochoa, Ashley

2016-01-01

Recovery from alcohol and drug problems is a process of change through which an individual achieves control and improved quality of life. Recovery is a primary goal for individuals with substance use disorder as it provides hope that treatment and overall health are possible for every individual. More than 23 million Americans are in recovery from addiction to alcohol and other drugs.Recovery-oriented systems of care (ROSC) are networks of community services and peer support that help individuals and families achieve recovery from substances and improve overall health. ROSC is a strengths-based and person-centered model that leverages existing community resources to address the needs of individuals and families as they progress through the journey of recovery. The ROSC model serves as the foundation of the Houston Recovery Initiative (HRI).The purpose of this article is to describe the history, development, and infrastructure of the HRI, which is a volunteer collaboration whose main goal is to educate the community on recovery and broaden the recovery safety net for people with substance use disorder in Houston, Texas. Since 2010, the HRI has grown to include more than 200 agencies across the spectrum of treatment and recovery support services in Houston so as to provide a resource for the community. Herein, we detail efforts to grow the HRI, lessons learned, future plans, and resources needed to move the HRI forward.

Lattice cell diffusion coefficients. Definitions and comparisons

International Nuclear Information System (INIS)

Hughes, R.P.

1980-01-01

Definitions of equivalent diffusion coefficients for regular lattices of heterogeneous cells have been given by several authors. The paper begins by reviewing these different definitions and the unification of their derivation. This unification makes clear how accurately each definition (together with appropriate cross-section definitions to preserve the eigenvalue) represents the individual reaction rates within the cell. The approach can be extended to include asymmetric cells and whereas before, the buckling describing the macroscopic flux shape was real, here it is found to be complex. A neutron ''drift'' coefficient as well as a diffusion coefficient is necessary to produce the macroscopic flux shape. The numerical calculation of the various different diffusion coefficients requires the solutions of equations similar to the ordinary transport equation for an infinite lattice. Traditional reactor physics codes are not sufficiently flexible to solve these equations in general. However, calculations in certain simple cases are presented and the theoretical results quantified. In difficult geometries, Monte Carlo techniques can be used to calculate an effective diffusion coefficient. These methods relate to those already described provided that correlation effects between different generations of neutrons are included. Again, these effects are quantified in certain simple cases. (author)

Heat transfer coefficient of cryotop during freezing.

Science.gov (United States)

Li, W J; Zhou, X L; Wang, H S; Liu, B L; Dai, J J

2013-01-01

Cryotop is an efficient vitrification method for cryopreservation of oocytes. It has been widely used owing to its simple operation and high freezing rate. Recently, the heat transfer performance of cryotop was studied by numerical simulation in several studies. However, the range of heat transfer coefficient in the simulation is uncertain. In this study, the heat transfer coefficient for cryotop during freezing process was analyzed. The cooling rates of 40 percent ethylene glycol (EG) droplet in cryotop during freezing were measured by ultra-fast measurement system and calculated by numerical simulation at different value of heat transfer coefficient. Compared with the results obtained by two methods, the range of the heat transfer coefficient necessary for the numerical simulation of cryotop was determined, which is between 9000 W/(m(2)·K) and 10000 W/(m (2)·K).

PET attenuation coefficients from CT images: experimental evaluation of the transformation of CT into PET 511-keV attenuation coefficients.

Science.gov (United States)

Burger, C; Goerres, G; Schoenes, S; Buck, A; Lonn, A H R; Von Schulthess, G K

2002-07-01

The CT data acquired in combined PET/CT studies provide a fast and essentially noiseless source for the correction of photon attenuation in PET emission data. To this end, the CT values relating to attenuation of photons in the range of 40-140 keV must be transformed into linear attenuation coefficients at the PET energy of 511 keV. As attenuation depends on photon energy and the absorbing material, an accurate theoretical relation cannot be devised. The transformation implemented in the Discovery LS PET/CT scanner (GE Medical Systems, Milwaukee, Wis.) uses a bilinear function based on the attenuation of water and cortical bone at the CT and PET energies. The purpose of this study was to compare this transformation with experimental CT values and corresponding PET attenuation coefficients. In 14 patients, quantitative PET attenuation maps were calculated from germanium-68 transmission scans, and resolution-matched CT images were generated. A total of 114 volumes of interest were defined and the average PET attenuation coefficients and CT values measured. From the CT values the predicted PET attenuation coefficients were calculated using the bilinear transformation. When the transformation was based on the narrow-beam attenuation coefficient of water at 511 keV (0.096 cm(-1)), the predicted attenuation coefficients were higher in soft tissue than the measured values. This bias was reduced by replacing 0.096 cm(-1) in the transformation by the linear attenuation coefficient of 0.093 cm(-1) obtained from germanium-68 transmission scans. An analysis of the corrected emission activities shows that the resulting transformation is essentially equivalent to the transmission-based attenuation correction for human tissue. For non-human material, however, it may assign inaccurate attenuation coefficients which will also affect the correction in neighbouring tissue.

Soccer ball lift coefficients via trajectory analysis

International Nuclear Information System (INIS)

Goff, John Eric; Carre, Matt J

2010-01-01

We performed experiments in which a soccer ball was launched from a machine while two high-speed cameras recorded portions of the trajectory. Using the trajectory data and published drag coefficients, we extracted lift coefficients for a soccer ball. We determined lift coefficients for a wide range of spin parameters, including several spin parameters that have not been obtained by today's wind tunnels. Our trajectory analysis technique is not only a valuable tool for professional sports scientists, it is also accessible to students with a background in undergraduate-level classical mechanics.

Soccer ball lift coefficients via trajectory analysis

Energy Technology Data Exchange (ETDEWEB)

Goff, John Eric [Department of Physics, Lynchburg College, Lynchburg, VA 24501 (United States); Carre, Matt J, E-mail: goff@lynchburg.ed [Department of Mechanical Engineering, University of Sheffield, Sheffield S1 3JD (United Kingdom)

2010-07-15

We performed experiments in which a soccer ball was launched from a machine while two high-speed cameras recorded portions of the trajectory. Using the trajectory data and published drag coefficients, we extracted lift coefficients for a soccer ball. We determined lift coefficients for a wide range of spin parameters, including several spin parameters that have not been obtained by today's wind tunnels. Our trajectory analysis technique is not only a valuable tool for professional sports scientists, it is also accessible to students with a background in undergraduate-level classical mechanics.

Factorization of Transport Coefficients in Macroporous Media

DEFF Research Database (Denmark)

Shapiro, Alexander; Stenby, Erling Halfdan

2000-01-01

We prove the fundamental theorem about factorization of the phenomenological coefficients for transport in macroporous media. By factorization we mean the representation of the transport coefficients as products of geometric parameters of the porous medium and the parameters characteristic...

Loop transfer recovery for general observer architecture

DEFF Research Database (Denmark)

Niemann, Hans Henrik; Søgaard-Andersen, Per; Stoustrup, Jakob

1991-01-01

A general and concise formulation is given of the loop transfer recovery (LTR) design problem based on recovery errors. Three types of recovery errors are treated: open loop recovery, sensitivity recovery and input-output recovery errors. The three corresponding versions of the asymptotic recovery...... recovery cases. This general recovery formulation covers all known observer based compensator types as special cases. The conditions given in this setting are effectively the aim of all known LTR design methods. The recovery formulation is interpreted in terms of a modelmatching problem as well, which...... is examined by means of the Q-parametrization. It is shown how the general controller obtained by the Q-parametrization can be written as a Luenberger observer based controller. In all cases, n controller states suffice to achieve recovery. The compensators are characterized for errors both on the input...

Quality of Recovery after Anesthesia: Validation of the Portuguese Version of the 'Quality of Recovery 15' Questionnaire.

Science.gov (United States)

Sá, Ana Carolina; Sousa, Gabriela; Santos, Alice; Santos, Cristina; Abelha, Fernando José

2015-01-01

The "Quality of Recovery 15" questionnaire is used for the study of quality recovery after anesthesia. The aim of this study was to validate the Portuguese version of "Quality of Recovery 15" questionnaire. After study approval by the institutional ethics committee, an observational and cohort prospective study was conducted on patients scheduled for elective surgery from June to August 2013. The "Quality of Recovery 15" questionnaire was translated in accordance with available guidelines. The "Quality of Recovery 15" Portuguese version was used before surgery (T0) and 24h postoperatively (T1) on 170 patients. Patients who were unable to give informed consent or had cognitive impairment were excluded. Poor quality of recovery was defined for "Quality of Recovery 15" score at T1 lower than the mean "Quality of Recovery 15" score minus 1 standard deviation. Reliability and observer disagreement was assessed using interclass correlation. Non-parametric tests were used for comparisons. There was a negative correlation between "Quality of Recovery 15" score and time spent in the postanesthesia care(p = -0.264, p = 0.004) and length of hospital stay (p = -0.274, p = 0.004). Thirty-two patients (19%) had poor quality of recovery. Patients with poor quality of recovery had more frequently diabetes mellitus and hypertension and they were taking antidepressants drugs more frequently. Patients with poor quality of recovery were more frequently submitted to combined anesthesia and less frequently to general anesthesia and locoregional anesthesia (p = 0.008). The questionnaire had a good internal consistency and test-retest reliability was good. The Portuguese version of the "Quality of Recovery 15" showed a good correlation with the original. This questionnaire appears to be an accurate and reliable assessment for quality of recovery.

The Time Course of the Loss and Recovery of Contracture Ability in Frog Striated Muscle Following Exposure to Ca-Free Solutions

Science.gov (United States)

Milligan, J. V.

1965-01-01

Using area under the contracture curve to quantitate contractures, the diffusion coefficient of calcium ions within the frog toe muscle during washout in a calcium-free solution and subsequent recovery after reintroduction of calcium to the bathing solution was calculated to be about 2 x 10-6 cm2/sec. The diffusion coefficient measured during washout was found to be independent of temperature or initial calcium ion concentration. During recovery it was found to decrease if the temperature was lowered. This was likely due to the repolarization occurring after the depolarizing effect of the calcium-free solution. The relation between contracture area and [Ca]o was found to be useful over a wider range than that between maximum tension and [Ca]o. The normalized contracture areas were larger at lower calcium concentrations if the contractures were produced with cold potassium solutions or if NO3 replaced Cl in the bathing solutions. Decreasing the potassium concentration of the contracture solution to 50 mM from 115 mM did not change the relation between [Ca]o and the normalized area. If the K concentration of the bathing solution was increased, the areas were decreased at lower concentrations of Ca. PMID:14324991

Monte Carlo based diffusion coefficients for LMFBR analysis

International Nuclear Information System (INIS)

Van Rooijen, Willem F.G.; Takeda, Toshikazu; Hazama, Taira

2010-01-01

A method based on Monte Carlo calculations is developed to estimate the diffusion coefficient of unit cells. The method uses a geometrical model similar to that used in lattice theory, but does not use the assumption of a separable fundamental mode used in lattice theory. The method uses standard Monte Carlo flux and current tallies, and the continuous energy Monte Carlo code MVP was used without modifications. Four models are presented to derive the diffusion coefficient from tally results of flux and partial currents. In this paper the method is applied to the calculation of a plate cell of the fast-spectrum critical facility ZEBRA. Conventional calculations of the diffusion coefficient diverge in the presence of planar voids in the lattice, but our Monte Carlo method can treat this situation without any problem. The Monte Carlo method was used to investigate the influence of geometrical modeling as well as the directional dependence of the diffusion coefficient. The method can be used to estimate the diffusion coefficient of complicated unit cells, the limitation being the capabilities of the Monte Carlo code. The method will be used in the future to confirm results for the diffusion coefficient obtained of the Monte Carlo code. The method will be used in the future to confirm results for the diffusion coefficient obtained with deterministic codes. (author)

Magnetic blocking direct-recovery efficiency

International Nuclear Information System (INIS)

Whealton, J.H.; Wooten, J.H.; McGaffey, R.W.

1981-10-01

The ion recovery efficiency of a transverse magnetic field monochromatic direct recovery device intended for intense neutral beams is examined theoretically by solving a Poisson-Vlasov equation. An optimum in recovery efficiency is obtained for finite ion current density and excess initial speed

Torsion method for measuring piezooptic coefficients

Energy Technology Data Exchange (ETDEWEB)

Skab, I.; Smaga, I.; Savaryn, V.; Vasylkiv, Yu.; Vlokh, R. [Institute of Physical Optics, Lviv (Ukraine)

2011-01-15

We develop and describe analytically a torsion method for measuring piezooptic coefficients associated with shear stresses. It is shown that the method enables to increase significantly the accuracy of determination of piezooptic coefficients. The method and the appropriate apparatus are verified experimentally on the example of LiNbO{sub 3} crystals. (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Transfer coefficients for terrestrial foodchain: their derivation and limitations

International Nuclear Information System (INIS)

Ng, Y.C.; Colsher, C.S.; Thompson, S.E.

1979-01-01

Transfer coefficients to predict the passage of isotopes from the environment to terrestrial foods have been derived for various radionuclides of importance in the nuclear fuel cycle. These data update and extend previously recommended handbook values. We derive transfer coefficients to terrestrial foods and describe the systematics of the derived transfer coefficients. Suggestions are offered for changes in the values of transfer coefficients to terrestrial foods that now appear in federal regulatory guides. Deficiencies in our present knowledge concerning transfer coefficients and limitations in the use of these values to ensure compliance with radiation protection standards are discussed

The use of helical heat exchanger for heat recovery domestic water-cooled air-conditioners

International Nuclear Information System (INIS)

Yi Xiaowen; Lee, W.L.

2009-01-01

An experimental study on the performance of a domestic water-cooled air-conditioner (WAC) using tube-in-tube helical heat exchanger for preheating of domestic hot water was carried out. The main aims are to identify the comprehensive energy performance (space cooling and hot water preheating) of the WAC and the optimum design of the helical heat exchanger taking into account the variation in tap water flow rate. A split-type WAC was set up for experimental study at different indoor and outdoor conditions. The cooling output, the amount of recovered heat, and the power consumption for different hot water flow rates were measured. The experimental results showed that the cooling coefficient of performance (COP) of the WAC improves with the inclusion of the heat recovery option by a minimum of 12.3%. This can be further improved to 20.6% by an increase in tap water flow rate. Same result was observed for the comprehensive COP of the WAC. The maximum achievable comprehensive COP was 4.92 when the tap water flow rate was set at 7.7 L/min. The overall heat transfer coefficient of the helical heat exchanger under various operating conditions were determined by Wilson plot. A mathematical model relating the over all heat transfer coefficient to the outer pipe diameter was established which provides a convenient way of optimising the design of the helical heat exchanger

Ideal related K-theory with coefficients

DEFF Research Database (Denmark)

Eilers, Soren; Restorff, Gunnar; Ruiz, Efren

2017-01-01

In this paper, we define an invariant, which we believe should be the substitute for total K-theory in the case when there is one distinguished ideal. Moreover, some diagrams relating the new groups to the ordinary K-groups with coefficients are constructed. These diagrams will in most cases help...... to determine the new groups, and will in a companion paper be used to prove a universal multi-coefficient theorem for the one distinguished ideal case for a large class of algebras......In this paper, we define an invariant, which we believe should be the substitute for total K-theory in the case when there is one distinguished ideal. Moreover, some diagrams relating the new groups to the ordinary K-groups with coefficients are constructed. These diagrams will in most cases help...

Novel Pendant Benzene Disulfonic Acid Blended SPPO Membranes for Alkali Recovery: Fabrication and Properties.

Science.gov (United States)

Mondal, Abhishek N; Dai, Chunhua; Pan, Jiefeng; Zheng, Chunlei; Hossain, Md Masem; Khan, Muhammad Imran; Wu, Liang; Xu, Tongwen

2015-07-29

To reconcile the trade-off between separation performance and availability of desired material for cation exchange membranes (CEMs), we designed and successfully prepared a novel sulfonated aromatic backbone-based cation exchange precursor named sodium 4,4'-(((((3,3'-disulfo-[1,1'-biphenyl]-4,4'-diyl)bis(oxy)) bis(4,1-phenylene))bis(azanediyl))bis(methylene))bis(benzene-1,3-disulfonate) [DSBPB] from 4,4'-bis(4-aminophenoxy)-[1,1'-biphenyl]-3,3'-disulfonic acid [BAPBDS] by a three-step procedure that included sulfonation, Michael condensation followed by reduction. Prepared DSBPB was used to blend with sulfonated poly(2,6-dimethyl-1,4-phenylene oxide) (SPPO) to get CEMs for alkali recovery via diffusion dialysis. Physiochemical properties and electrochemical performance of prepared membranes can be tuned by varying the dosage of DSBPB. All the thermo-mechanical properties like DMA and TGA were investigated along with water uptake (WR), ion exchange capacity (IEC), dimensional stability, etc. The effect of DSBPB was discussed in brief in connection with alkali recovery and ion conducting channels. The SPPO/DSBPB membranes possess both high water uptake as well as ion exchange capacity with high thermo-mechanical stability. At 25 °C the dialysis coefficients (UOH) appeared to be in the range of 0.0048-0.00814 m/h, whereas the separation factor (S) ranged from 12.61 to 36.88 when the membranes were tested for base recovery in Na2WO4/NaOH waste solution. Prepared membranes showed much improved DD performances compared to traditional SPPO membrane and possess the potentiality to be a promising candidate for alkali recovery via diffusion dialysis.

Recovery of uranium and of rare earths from Moroccan phosphates

International Nuclear Information System (INIS)

Ezahr, I.; El Houari, A.; Smani, S.M.

1984-01-01

The contents of uranium and of rare earths in Moroccan phosphates vary from 75 to 250 ppm and from 900 to 1500 ppm, respectively. The phosphates produced in Morocco contain therefore about 2500 t of uranium and 25 000 t of rare earths, compared with annual productions of uranium and of rare earths of 43 000 t and 33 000 t, respectively. During the sulphuric leaching of the phosphate ores, uranium is found to 80-90% in the phosphoric acid. Research into the extraction of uranium has shown that for the phosphoric acids produced at Safi the coefficient of extraction: is not very sensitive to the P 2 O 5 concentration on the 28-30% region; is not affected by the sulphur level up to the concentration of 4%; is very sensitive to the fluorine content beyond 1%. On the level of the first cycle of the process in Depa-Topo, four extraction stages permit a yield of between 92 and 98% to be reached. The addition of an oxidizing agent to the phosphoric acids under examination was not necessary, as their potential level is high. The purity of the yellow-cakes obtained varies from 94 to 99%. The overall recovery efficiency lies between 67 and 71%. In a second part, this paper deals with the recovery of the rare earths [fr

Resummed coefficient function for the shape function

OpenAIRE

Aglietti, U.

2001-01-01

We present a leading evaluation of the resummed coefficient function for the shape function. It is also shown that the coefficient function is short-distance-dominated. Our results allow relating the shape function computed on the lattice to the physical QCD distributions.

Alternatives to Pearson's and Spearman's Correlation Coefficients

OpenAIRE

Smarandache, Florentin

2008-01-01

This article presents several alternatives to Pearson's correlation coefficient and many examples. In the samples where the rank in a discrete variable counts more than the variable values, the mixtures that we propose of Pearson's and Spearman's correlation coefficients give better results.

Course of Recovery from Alcoholism

Science.gov (United States)

Venner, Kamilla L.; Matzger, Helen; Forcehimes, Alyssa A.; Moos, Rudolf H.; Feldstein, Sarah W.; Willenbring, Mark L.; Weisner, Constance

2010-01-01

This article represents the proceedings of a symposium at the 2005 Research Society on Alcoholism meeting in Santa Barbara, California, organized and chaired by Kamilla L. Venner. This symposium integrated current empirical research on the course of recovery from alcoholism from multiple perspectives, an aim that is consistent with NIAAA's new focus on the process of recovery. The presentations and presenters were as follows: (1) The Role of Community Services and Informal Support on 7-Year Drinking Outcomes in Treated and Untreated Drinkers, by Helen Matzger; (2) The Sequence of Recovery Events in a Native American Sample, by Kamilla L. Venner; (3) Transformational Change in Recovery, by Alyssa A. Forcehimes; (4) Social Settings and Substance Use: Contextual Factors in Recovery, by Rudolf H. Moos; and (5) A Broader View of Change in Drinking Behavior, by discussant Mark L. Willenbring. A theme connecting the presentations was that treatment is but one discrete aspect to recovery and that sustained recovery is often influenced by an individual interaction with others within a social context. Collectively, presentations underscored the need to think more broadly about factors contributing to the remission of alcohol dependence. PMID:16737468

Coefficients of tracer transfer through membranes. Pt. 7

Energy Technology Data Exchange (ETDEWEB)

Dorabialska, A; Hawlicka, E; Plonka, A [Politechnika Lodzka (Poland)

1974-01-01

The doubled value of the tracer transfer coefficient in the self-diffusion process is equal to the sum of tracer transfer coefficients in the diffusion and interfusion processes. The fundamental phenomenological relation can be deduced for the coefficients of tracer transfer between two phases of electrolyte solutions spearated by a virtual boundary. Indeed, the doubled value of the tracer mobility in the self-diffusion experiment (no concentration gradient of the traced substance) is equal to the sum of the tracer mobilities in the diffusion (tracer movement along with the concentration gradient of the traced substance) and interfusion experiments (tracer movement against the concentration gradient of the traced substance). Thus the doubled value of the tracer transfer coefficient in the self-diffusion process should be equal to the sum of tracer transfer coefficients in the diffusion and interfusion processes. The experimental verification of that fundamental relation is presented.

Algebraic polynomials with random coefficients

Directory of Open Access Journals (Sweden)

K. Farahmand

2002-01-01

Full Text Available This paper provides an asymptotic value for the mathematical expected number of points of inflections of a random polynomial of the form a0(ω+a1(ω(n11/2x+a2(ω(n21/2x2+…an(ω(nn1/2xn when n is large. The coefficients {aj(w}j=0n, w∈Ω are assumed to be a sequence of independent normally distributed random variables with means zero and variance one, each defined on a fixed probability space (A,Ω,Pr. A special case of dependent coefficients is also studied.

Estimating varying coefficients for partial differential equation models.

Science.gov (United States)

Zhang, Xinyu; Cao, Jiguo; Carroll, Raymond J

2017-09-01

Partial differential equations (PDEs) are used to model complex dynamical systems in multiple dimensions, and their parameters often have important scientific interpretations. In some applications, PDE parameters are not constant but can change depending on the values of covariates, a feature that we call varying coefficients. We propose a parameter cascading method to estimate varying coefficients in PDE models from noisy data. Our estimates of the varying coefficients are shown to be consistent and asymptotically normally distributed. The performance of our method is evaluated by a simulation study and by an empirical study estimating three varying coefficients in a PDE model arising from LIDAR data. © 2017, The International Biometric Society.

Improved Materials for Use as Components in Kraft Black Liquor Recovery Boilers; TOPICAL

International Nuclear Information System (INIS)

Keiser, J.R.

2001-01-01

This Cooperative Research and Development Agreement (CRADA) was undertaken to evaluate current and improved materials and materials processing conditions for use as components in kraft black liquor recovery boilers and other unit processes. The main areas addressed were: (1) Improved Black Liquor Nozzles, (2) Weld Overlay of Composite Floor Tubes, and (3) Materials for Lime Kilns. Iron aluminide was evaluated as an alternate material for the nozzles used to inject an aqueous solution known as black liquor into recovery boilers as well for the uncooled lining in the ports used for the nozzles. Although iron aluminide is known to have much better sulfidation resistance in gases than low alloy and stainless steels, it did not perform adequately in the environment where it came into contact with molten carbonate, sulfide and sulfate salts. Weld overlaying carbon steel tubes with a layer of stainless weld metal was a proposed method of extending the life of recovery boiler floor tubes that have experienced considerable fireside corrosion. After exposure under service conditions, sections of weld overlaid floor tubes were removed from a boiler floor and examined metallographically. Examination results indicated satisfactory performance of the tubes. Refractory-lined lime kilns are a critical component of the recovery process in kraft pulp mills, and the integrity of the lining is essential to the successful operation of the kiln. A modeling study was performed to determine the cause of, and possible solutions for, the repeated loss of the refractory lining from the cooled end of a particular kiln. The evaluation showed that the temperature, the brick shape and the coefficient of friction between the bricks were the most important parameters influencing the behavior of the refractory lining

Clebsch-Gordan and Racah coefficients of SUpq(2)

International Nuclear Information System (INIS)

Kachurik, I.I.

1993-01-01

Explicit expressions for the Clebsch-Gordan coefficients and for the Racah coefficients of the two-parametric quantum algebra SU pq (2) are derived. They are given as finite sums and as terminating basic hypergeometric functions 3 φ 2 and 4 φ 3 . It is indicated how other expressions for these coefficients can be derived with the help of basic hypergeometric functions. (author). 11 refs

On some properties of SU(3 fusion coefficients

Directory of Open Access Journals (Sweden)

Robert Coquereaux

2016-11-01

Full Text Available Three aspects of the SU(3 fusion coefficients are revisited: the generating polynomials of fusion coefficients are written explicitly; some curious identities generalizing the classical Freudenthal–de Vries formula are derived; and the properties of the fusion coefficients under conjugation of one of the factors, previously analyzed in the classical case, are extended to the affine algebra suˆ(3 at finite level.

Membrane mobility and microdomain association of the dopaminetransporter studied with fluorescence correlation spectroscopy and fluorescence recovery after photobleaching

DEFF Research Database (Denmark)

Adkins, Erika; Samuvel, Devadoss; Fog, Jacob

2007-01-01

To investigate microdomain association of the dopamine transporter (DAT), we employed FCS (fluorescence correlation spectroscopy) and FRAP (fluorescence recovery after photobleaching). In non-neuronal cells (HEK293), FCS measurements revealed for the YFP-DAT (DAT tagged with yellow fluorescent...... protein) a diffusion coefficient (D) of ~3.6 × 10-9 cm2/s, consistent with a relatively freely diffusible protein. In neuronally derived cells (N2a), we were unable to perform FCS measurements on plasma membrane-associated protein due to photobleaching, suggesting partial immobilization...

Variable-coefficient higher-order nonlinear Schroedinger model in optical fibers: Variable-coefficient bilinear form, Baecklund transformation, brightons and symbolic computation

International Nuclear Information System (INIS)

Tian Bo; Gao Yitian; Zhu Hongwu

2007-01-01

Symbolically investigated in this Letter is a variable-coefficient higher-order nonlinear Schroedinger (vcHNLS) model for ultrafast signal-routing, fiber laser systems and optical communication systems with distributed dispersion and nonlinearity management. Of physical and optical interests, with bilinear method extend, the vcHNLS model is transformed into a variable-coefficient bilinear form, and then an auto-Baecklund transformation is constructed. Constraints on coefficient functions are analyzed. Potentially observable with future optical-fiber experiments, variable-coefficient brightons are illustrated. Relevant properties and features are discussed as well. Baecklund transformation and other results of this Letter will be of certain value to the studies on inhomogeneous fiber media, core of dispersion-managed brightons, fiber amplifiers, laser systems and optical communication links with distributed dispersion and nonlinearity management

Micro- and macroscale coefficients of friction of cementitious materials

International Nuclear Information System (INIS)

Lomboy, Gilson; Sundararajan, Sriram; Wang, Kejin

2013-01-01

Millions of metric tons of cementitious materials are produced, transported and used in construction each year. The ease or difficulty of handling cementitious materials is greatly influenced by the material friction properties. In the present study, the coefficients of friction of cementitious materials were measured at the microscale and macroscale. The materials tested were commercially-available Portland cement, Class C fly ash, and ground granulated blast furnace slag. At the microscale, the coefficient of friction was determined from the interaction forces between cementitious particles using an Atomic Force Microscope. At the macroscale, the coefficient of friction was determined from stresses on bulk cementitious materials under direct shear. The study indicated that the microscale coefficient of friction ranged from 0.020 to 0.059, and the macroscale coefficient of friction ranged from 0.56 to 0.75. The fly ash studied had the highest microscale coefficient of friction and the lowest macroscale coefficient of friction. -- Highlights: •Microscale (interparticle) coefficient of friction (COF) was determined with AFM. •Macroscale (bulk) COF was measured under direct shear. •Fly ash had the highest microscale COF and the lowest macroscale COF. •Portland cement against GGBFS had the lowest microscale COF. •Portland cement against Portland cement had the highest macroscale COF

Heat transfer coefficient for boiling carbon dioxide

DEFF Research Database (Denmark)

Knudsen, Hans Jørgen Høgaard; Jensen, Per Henrik

1998-01-01

Heat transfer coefficient and pressure drop for boiling carbon dioxide (R744) flowing in a horizontal pipe has been measured. The calculated heat transfer coeeficient has been compared with the Chart correlation of Shah. The Chart Correlation predits too low heat transfer coefficient but the ratio...... between the measured and the calculated heat transfer coefficient is nearly constant and equal 1.9. With this factor the correlation predicts the measured data within 14% (RMS). The pressure drop is of the same order as the measuring uncertainty and the pressure drop has not been compared with correlation's....

Analysis of stable components in the extended-range forecast for the coming 10–30 days in winter 2010 and 2011

International Nuclear Information System (INIS)

Wang Kuo; Zeng Yu-Xing; Wang Xu-Jia; Feng Guo-Lin

2013-01-01

In this paper we try to extract stable components in the extended-range forecast for the coming 10–30 days by using empirical orthogonal function (EOF) analysis, similarity coefficient, and some other methods based on the National Center for Environmental Prediction (NCEP)/National Center for Atmospheric Research (NCAR) reanalysis daily data. The comparisons of the coefficient of variance of climatological background field and truth data in winter between 2010 and 2011 are made. The method of extracting stable components and climatological background field can be helpful to increase forecasting skill. The forecasting skill improvement of air temperature is better than geopotential height at 500 hPa. Moreover, this method improves the predictability better in the Pacific Ocean. In China, the forecast in winter in Northeast China is more uncertain than in the other parts. (geophysics, astronomy, and astrophysics)

Defining recovery in adult bulimia nervosa.

Science.gov (United States)

Yu, Jessica; Agras, W Stewart; Bryson, Susan

2013-01-01

To examine how different definitions of recovery lead to varying rates of recovery, maintenance of recovery, and relapse in bulimia nervosa (BN), end-of-treatment (EOT) and follow-up data were obtained from 96 adults with BN. Combining behavioral, physical, and psychological criteria led to recovery rates between 15.5% and 34.4% at EOT, though relapse was approximately 50%. Combining these criteria and requiring abstinence from binge eating and purging when defining recovery may lead to lower recovery rates than those found in previous studies; however, a strength of this definition is that individuals who meet this criteria have no remaining disordered behaviors or symptoms.

Probabilistic accident sequence recovery analysis

International Nuclear Information System (INIS)

Stutzke, Martin A.; Cooper, Susan E.

2004-01-01

Recovery analysis is a method that considers alternative strategies for preventing accidents in nuclear power plants during probabilistic risk assessment (PRA). Consideration of possible recovery actions in PRAs has been controversial, and there seems to be a widely held belief among PRA practitioners, utility staff, plant operators, and regulators that the results of recovery analysis should be skeptically viewed. This paper provides a framework for discussing recovery strategies, thus lending credibility to the process and enhancing regulatory acceptance of PRA results and conclusions. (author)

Recovery of antimony-125 from tin-124 irradiated by neutrons

International Nuclear Information System (INIS)

Baluev, A.V.; Mityakhina, V.S.; Krasnikov, L.V.; Galkin, B.Ya.; Besnosyuk, V.I.

2003-01-01

Separation of 125 Sb from tin using highly basic, medium-basic, and weakly basic ion-exchangers was studied. The best results were obtained for AN-31 weakly basic anion exchanger. The yield of 125 Sb was 95 -98 % of the initial activity, the yield of tin, 98 ± 0.5% of the initial amount. The separation coefficient is 10 6 -10 7 for one cycle. A procedure based on ion exchange was developed. Extraction procedures of separation of 125 Sb from tin were studied. Isoamyl alcohol, ethyl acetate, and di-n-butyl ether were used as extracting agents. The most efficient extracting agent is di-n-butyl ether. Carrier-free radiochemically pure sample of 125 Sb was produced. More than 20 mCi of the target product was recovered. The extraction recovery procedure of 125 Sb has been developed. (author)

Power coefficient anomaly in Joyo, (2)

International Nuclear Information System (INIS)

Ishikawa, Makoto; Yamashita, Yoshioki; Sasaki, Makoto; Nara, Yoshihiko.

1981-12-01

In this report, the presumption about the mechanism having caused the power coefficient anomaly in Joyo during the 75 MW power-raising test in 1979 is described. After the previous report, the new information about the results of the post-irradiation examination and the analysis of the power coefficient of Joyo were able to be obtained. From these information, the mechanism of causing the anomaly was presumed as follows. In 50 MW operation, the fuel burnup reached about 10,000 MWD/ton at the end of second cycle, and produced fission gas was almost retained in fuel pellets. When the power was raised from 50 MW to 75 MW for the first time, the fission gas began to be released when 50 MW was somewhat exceeded. The fission gas release caused the temperature rise and cracking of fuel pellets, and elongated fuel stack length abruptly. These phenomena induced to enlarge the fuel expansion reactivity effect and Doppler reactivity effect, and caused the anomalous behavior of power coefficient. After reaching 75 MW, the fuel stack length did not respond normally to reactor power change, and the magnitude of power coefficient became smaller. The reactivity was lost considerably from the core after the anomaly. (Kako, I.)

Transport Coefficients for dense hard-disk systems

NARCIS (Netherlands)

Garcia-Rojo, R.; Luding, Stefan; Brey, J. Javier; Ooms, G.; Hoogendoorn, C.J.

2007-01-01

A study of the transport coefficients of a system of elastic hard disks, based on the use of Helfand-Einstein expressions is reported. The pressure, the viscosity, and the heat conductivity are examined for different density and system-size. While most transport coefficients agree with Enskog theory

Riesz frames and approximation of the frame coefficients

DEFF Research Database (Denmark)

Casazza, P.; Christensen, Ole

1998-01-01

A frame is a fmaily {f i } i=1 ∞ of elements in a Hilbert space with the property that every element in can be written as a (infinite) linear combination of the frame elements. Frame theory describes how one can choose the corresponding coefficients, which are called frame coefficients. From...... the mathematical point of view this is gratifying, but for applications it is a problem that the calculation requires inversion of an operator on . The projection method is introduced in order to avoid this problem. The basic idea is to consider finite subfamilies {f i } i=1 n of the frame and the orthogonal...... projection Pn onto its span. For has a representation as a linear combination of fi, i=1,2,..., n and the corresponding coefficients can be calculated using finite dimensional methods. We find conditions implying that those coefficients converge to the correct frame coefficients as n→∞, in which case we have...

Regional water coefficients for U.S. industrial sectors

Directory of Open Access Journals (Sweden)

Riccardo Boero

2017-12-01

Full Text Available Designing policies for water systems management requires the capability to assess the economic impacts of water availability and to effectively couple water withdrawals by human activities with natural hydrologic dynamics. At the core of any scientific approach to these issues there is the estimation of water withdrawals by industrial sectors in the form of water coefficients, which are measurements of the quantity of water withdrawn per dollar of GDP or output. In this work we focus on the contiguous United States and on the estimation of water coefficients for regional scale analyses. We first compare an established methodology for the estimation of national water coefficients with a parametric one we propose. Second, we introduce a method to estimate water coefficients at the level of ecological regions and we discuss how they reduce possible biases in regional analyses of water systems. We conclude discussing advantages and limits of regional water coefficients.

Numerical Modeling of Fin and Tube Heat Exchanger for Waste Heat Recovery

DEFF Research Database (Denmark)

Singh, Shobhana; Sørensen, Kim; Condra, Thomas Joseph

In the present work, multiphysics numerical modeling is carried out to predict the performance of a liquid-gas fin and tube heat exchanger design. Three-dimensional (3D) steady-state numerical model using commercial software COMSOL based on finite element method (FEM) is developed. The study...... associates conjugate heat transfer phenomenon with the turbulent flow to describe the variable temperature and velocity profile. The performance of heat exchanger design is investigated in terms of overall heat transfer coefficient, Nusselt number, Colburn j-factor, flow resistance factor, and efficiency...... between fin and tube. The present numerical model predicts the performance of the heat exchanger design, therefore, can be applied to existing waste heat recovery systems to improve the overall performance with optimized design and process-dependent parameters....

Heart Attack Recovery FAQs

Science.gov (United States)

... recommendations to make a full recovery. View an animation of a heart attack . Heart Attack Recovery Questions ... Support Network Popular Articles 1 Understanding Blood Pressure Readings 2 Sodium and Salt 3 Heart Attack Symptoms ...

On finding algebraic expressions for genealogical coefficients

International Nuclear Information System (INIS)

Kanyauskas, J.M.; Shimonis, V.Ch.; Rudzikas, Z.B.

1979-01-01

It has been attempted to obtain analytical expressions for genealogical coefficients with one detached electron in the case of L-S coupling. A method of second quantization and tensorial properties of the quasi-spin operator are applied. It is restricted to the states for the classification of which the seigniority quantum number v is sufficient. Three ways of the acquirement of these expressions are discussed: 1. In the recurrent way wave functions of N and N-1 electrons are built, consequently expressing these functions in terms of the creation-annihilation operators. 2. Recurrent summation with the use of evident, simple genealogical coefficients. 3. Using the ratios, connecting the genealogical coefficients with the normalized multiplier. The data are presented in formulae and discussions. The generalization of the Redmond's formula is obtained and relatively simple algebraic expressions of the genealogical coefficients of the equivalent electron configurations, for the distinction of the recurrent terms of which introduction of the seigniority quantum number v is sufficient, are given

Rate coefficient for the reaction N + NO

Science.gov (United States)

Fox, J. L.

1994-01-01

Evidence has been advanced that the rate coefficient for the reaction N + NO right arrow N2 + O has a small positive temperature dependence at the high temperatures (900 to 1500 K) that prevail in the terrestrial middle and upper thermosphere by Siskind and Rusch (1992), and at the low temperatures (100 to 200 K) of the Martian lower thermosphere by Fox (1993). Assuming that the rate coefficient recommended by the Jet Propulsion Laboratory evaluation (DeMore et al., 1992) is accurate at 300 K, we derive here the low temperature value of the activation energy for this reaction and thus the rate coefficient that best fits the Viking 1 measured NO densities. We find that the fit is acceptable for a rate coefficient of about 1.3 x 10(exp -10)(T/300)(exp 0.5)exp(-400/T) and better for a value of about 2.5 x 10(exp -10)(T/300)(exp 0.5)exp(-600/T)cu cm/s.

Spatially Dispersed Employee Recovery

DEFF Research Database (Denmark)

Hvass, Kristian Anders; Torfadóttir, Embla

2014-01-01

Employee recovery addresses either employee well-being or management's practices in aiding employees in recovering themselves following a service failure. This paper surveys the cabin crew at a small, European, low-cost carrier and investigates employees' perceptions of management practices to aid...... personnel achieve service recovery. Employee recovery within service research often focuses on front-line employees that work in a fixed location, however a contribution to the field is made by investigating the recovery of spatially dispersed personnel, such as operational personnel in the transport sector......, who have a work place away from a fixed or central location and have minimal management contact. Results suggest that the support employees receive from management, such as recognition, information sharing, training, and strategic awareness are all important for spatially dispersed front...

Structuring Disaster Recovery Infrastructure Decisions: Lessons from Boulder County's 2013 Flood Recovery

Science.gov (United States)

Clavin, C.; Petropoulos, Z.

2017-12-01

Recovery phase decision making processes, as compared to mitigation and response phase decision making processes, require communities make significant financial and capital decisions in the months after a disaster. Collectively, these investments may significantly contribute to the resilience of a community to future hazards. Pre-disaster administrative decisions are well-established within existing planning processes. Post-event recovery requires community decision makers to quickly evaluate technical proposals and manage significant recovery financial resources to ensure their community rebuilds in a manner that will be more resilient to future events. These technical and administrative hurdles in the aftermath of a disaster create a challenging atmosphere to make sound, scientifically-informed decisions leading to resilient recovery. In September 2013, a 1,000-year rain event that resulted in flooding throughout the Front Range of Colorado, significantly impacting Boulder County. While the event is long past, disaster recovery efforts still continue in parts of Boulder County. Boulder County officials formed a county collaborative that adapted the NIST Community Resilience Planning Guide for Buildings and Infrastructure Systems to facilitate a goals-based multi-criteria decision making process. Rather than use hazard-based information to guide infrastructure design, the county's decision process established time-to-recovery goals for infrastructure systems that were used as criteria for project design. This presentation explores the decision-making process employed by Boulder County to specify design standards for resilient rebuilding of infrastructure systems and examine how this infrastructure planning model could be extrapolated to other situations where there is uncertainty regarding future infrastructure design standards.

The Binomial Coefficient for Negative Arguments

OpenAIRE

Kronenburg, M. J.

2011-01-01

The definition of the binomial coefficient in terms of gamma functions also allows non-integer arguments. For nonnegative integer arguments the gamma functions reduce to factorials, leading to the well-known Pascal triangle. Using a symmetry formula for the gamma function, this definition is extended to negative integer arguments, making the symmetry identity for binomial coefficients valid for all integer arguments. The agreement of this definition with some other identities and with the bin...

A method to simulate motor control strategies to recover from perturbations: application to a stumble recovery during gait.

Science.gov (United States)

Forner-Cordero, Arturo; Ackermann, Marko; de Lima Freitas, Mateus

2011-01-01

Perturbations during human gait such as a trip or a slip can result in a fall, especially among frail populations such as the elderly. In order to recover from a trip or a stumble during gait, humans perform different types of recovery strategies. It is very useful to uncover the mechanisms of the recovery to improve training methods for populations at risk of falling. Moreover, human recovery strategies could be applied to implement controllers for bipedal robot walker, as an application of biomimetic design. A biomechanical model of the response to a trip during gait might uncover the control mechanisms underlying the different recovery strategies and the adaptation of the responses found during the execution of successive perturbation trials. This paper introduces a model of stumble in the multibody system framework. This model is used to assess different feedforward strategies to recover from a trip. First of all, normal gait patterns for the musculoskeletal system model are obtained by solving an optimal control problem. Secondly, the reference gait is perturbed by the application of forces on the swinging foot in different ways: as an instantaneous inelastic collision of the foot with an obstacle, as an impulsive horizontal force or using a force curve measured experimentally during gait perturbation experiments. The influence of the type of perturbation, the timing of the collision with respect to the gait cycle, as well as of the coefficient of restitution was investigated previously. Finally, in order to test the effects of different muscle excitation levels on the initial phases of the recovery response, several muscle excitations were added to selected muscles of the legs, thus providing a simulation of the recovery reactions. These results pave the way for future analysis and modeling of the control mechanisms of gait.

Forecast Correlation Coefficient Matrix of Stock Returns in Portfolio Analysis

OpenAIRE

Zhao, Feng

2013-01-01

In Modern Portfolio Theory, the correlation coefficients decide the risk of a set of stocks in the portfolio. So, to understand the correlation coefficients between returns of stocks, is a challenge but is very important for the portfolio management. Usually, the stocks with small correlation coefficients or even negative correlation coefficients are preferred. One can calculate the correlation coefficients of stock returns based on the historical stock data. However, in order to control the ...

Negative power coefficient on PHWRs with CARA fuel

International Nuclear Information System (INIS)

Lestani, H.A.; González, H.J.; Florido, P.C.

2014-01-01

Highlights: • A PHWR fuel was optimized to obtain a negative power coefficient. • Fuel cost, being a measure of design investment efficiency, was optimized. • Influence on power coefficient of geometrical and economical parameters’ was studied. • Different neutronic absorbers were studied; pure absorbers can be used. • Thermal and economical models were developed to complement neutronic assessment. - Abstract: A study of power coefficient of reactivity in heavy water reactors is made analyzing the reactivity components of fuels with several modifications oriented at reducing the coefficient. A cell model is used for neutronics calculations; a non-linear two dimensional model is used to evaluate the thermal changes that follow a power change; and a levelized unit energy cost model is used to assess the economical feasibility of the design changes introduced to reduce power coefficient. The necessity of modelling all the aforementioned quantities in a coupled scheme is stressed, as a strong interdependence was found. A series of design changes complied with a negative power coefficient of reactivity, with a feasible power radial distribution and with low refuelling cost. Some investigation lines that exceed the fuel cell study and deal with the plant operation are marked as potentially addressing the stable operation of big heavy water reactors

Exploring the Framework Hydrophobicity and Flexibility of ZIF-8: From Biofuel Recovery to Hydrocarbon Separations

KAUST Repository

Zhang, Ke

2013-11-07

The framework hydrophobicity and flexibility of ZIF-8 are investigated by a detailed adsorption and diffusion study of a series of probe molecules including ethanol, 1-butanol, water, hexane isomers, xylene isomers, and 1,2,4-trimethylbenzene. The prospects for using ZIF-8 in biofuel recovery and hydrocarbon separations are discussed in terms of adsorption or kinetic selectivities. ZIF-8 shows extremely low water vapor uptakes and is especially suitable for vapor phase butanol-based biofuel recovery. The extraordinary framework flexibility of ZIF-8 is demonstrated by the adsorption of hydrocarbon molecules that are much larger than its nominal pore size, such as m-xylene, o-xylene and 1,2,4-trimethylbenzene. The calculation of corrected diffusion coefficients reveals an interesting spectrum of promising kinetic hydrocarbon separations by ZIF-8. These findings confirm that a molecular sieving effect tends to occur in the sorbate molecular size range of 4-6 Å rather than around the nominal ZIF-8 pore size of 3.4 Å, due to its surprising framework flexibility. © 2013 American Chemical Society.

Minimum wall pressure coefficient of orifice plate energy dissipater

Directory of Open Access Journals (Sweden)

Wan-zheng Ai

2015-01-01

Full Text Available Orifice plate energy dissipaters have been successfully used in large-scale hydropower projects due to their simple structure, convenient construction procedure, and high energy dissipation ratio. The minimum wall pressure coefficient of an orifice plate can indirectly reflect its cavitation characteristics: the lower the minimum wall pressure coefficient is, the better the ability of the orifice plate to resist cavitation damage is. Thus, it is important to study the minimum wall pressure coefficient of the orifice plate. In this study, this coefficient and related parameters, such as the contraction ratio, defined as the ratio of the orifice plate diameter to the flood-discharging tunnel diameter; the relative thickness, defined as the ratio of the orifice plate thickness to the tunnel diameter; and the Reynolds number of the flow through the orifice plate, were theoretically analyzed, and their relationships were obtained through physical model experiments. It can be concluded that the minimum wall pressure coefficient is mainly dominated by the contraction ratio and relative thickness. The lower the contraction ratio and relative thickness are, the larger the minimum wall pressure coefficient is. The effects of the Reynolds number on the minimum wall pressure coefficient can be neglected when it is larger than 105. An empirical expression was presented to calculate the minimum wall pressure coefficient in this study.

In vivo 31P NMR spectroscopic assessment of the endurance and recovery capacity of skeletal muscle: Comparison between the sedentaries and canoe athletes

International Nuclear Information System (INIS)

Lim, Tae Hawn; Lee, Tae Keun; Seong, Ki Hong; Mun, Chi Woong; Kim, Sang Tae; Shin, Myung Jin

1992-01-01

In vivo 3P NMR spectroscopic study of forearm wrist flexor muscles was performed in two groups of volunteers composed respectively of 6 sedentaries and 6 canoe athletes. A continuous isometric contraction of endurance exercise was adopted in order to assess the endurance capacity and recovery potential of skeletal muscles. Differences in high energy phosphorus metabolism between the sedentaries and athletes were evaluated with and emphasis on the intracellular pH and Pi/PCr ratio as indicators of high energy phosphorus metabolism, There were no differences of baseline pH and Pi/ PCr ratio between the two groups. The athletes sustained the exercise at a more acidic intracellular pH and at a higher Pi/ PCr radio of intracellular conditions for an all out than did the sedentaries. The recovery rate of pH showed no difference between the two groups. There was a tendency of faster recovery of Pi/ PCr in athletes showing half recovery time (T 1/2 ) of 39.0 ± 3.0 seconds as compared to that of sedentaries (55.7 ± 7.5 seconds). The recovery rate of Pi/ PCr as a function of Pi/ PCr rate at a given period of time was significantly faster in athletes than in sedentaries (P<0.001). The correlation coefficient of the recovery rate of Pi/ PCr against the Pi/ PCr ratio was 0.985 and 0.914 respectively for the athletes and sedentaries. The pH and the Pi/ PCr ratio at an all-out state can be used as indicators of endurance capacity and the recovery rate of Pi/ PCr, as a recovery potential of skeletal muscles

Network Efficiency and Posterior Alpha Patterns Are Markers of Recovery from General Anesthesia: A High-Density Electroencephalography Study in Healthy Volunteers

Directory of Open Access Journals (Sweden)

Stefanie Blain-Moraes

2017-06-01

Full Text Available Recent studies have investigated local oscillations, long-range connectivity, and global network patterns to identify neural changes associated with anesthetic-induced unconsciousness. These studies typically employ anesthetic protocols that either just cross the threshold of unconsciousness, or induce deep unconsciousness for a brief period of time—neither of which models general anesthesia for major surgery. To study neural patterns of unconsciousness and recovery in a clinically-relevant context, we used a realistic anesthetic regimen to induce and maintain unconsciousness in eight healthy participants for 3 h. High-density electroencephalogram (EEG was acquired throughout and for another 3 h after emergence. Seven epochs of 5-min eyes-closed resting states were extracted from the data at baseline as well as 30, 60, 90, 120, 150, and 180-min post-emergence. Additionally, 5-min epochs were extracted during induction, unconsciousness, and immediately prior to recovery of consciousness, for a total of 10 analysis epochs. The EEG data in each epoch were analyzed using source-localized spectral analysis, phase-lag index, and graph theoretical techniques. Posterior alpha power was significantly depressed during unconsciousness, and gradually approached baseline levels over the 3 h recovery period. Phase-lag index did not distinguish between states of consciousness or stages of recovery. Network efficiency was significantly depressed and network clustering coefficient was significantly increased during unconsciousness; these graph theoretical measures returned to baseline during the 3 h recovery period. Posterior alpha power may be a potential biomarker for normal recovery of functional brain networks after general anesthesia.

Damage Recovery in Carrara Marble

Science.gov (United States)

Meyer, G.; Brantut, N.; Mitchell, T. M.; Meredith, P. G.

2017-12-01

We investigate the effect of confining pressure on the recovery of elastic wave velocities following deformation episodes in Carrara Marble. Dry Carrara Marble cores were deformed in the ductile regime (Pc = 40 MPa) up to 3% axial strain. After deformation, samples were held at constant stress conditions for extended periods of time (5-8 days) whilst continuously recording volumetric strain and seismic wave velocities. The velocity data were used to invert for microcrack densities using an effective medium approach. Finally, thin sections were produced to characterise the microstructures after recovery. During deformation, elastic wave speeds decreased with increasing strain by more than 30% of the value for the intact rock due to the formation of distributed microcracks. Under constant hydrostatic pressure, wave speeds progressively recovered 12-90% of the initial drop, depending on the applied confining pressure. In contrast, the strain recovery (deformation towards the initial shape of the sample) during holding time is negligible (of the order of 10-4). Tests performed under nonhydrostatic (triaxial) stress conditions during recovery showed some time-dependent creep deformation together with very significant recovery of wave velocities. The recovery is interpreted as a progressive reduction in crack density within the sample. The process is highly dependent on confining pressure, which favours it. We propose that the driving process for wave speed recovery is the time-dependent increase of contact area between crack surfaces due to the formation and growth of asperity contacts. We develop a micromechanical model for crack closure driven by asperity creep, which shows a good fit to the experimental data. Most of the recovery is achieved in the initial few hours, implying it is the fastest recovery or healing process, and thus occurs prior to any chemical healing or mineral precipitation. Our data corroborate field observations of post-seismic fault behavior.

Simultaneous Description of Activity Coefficients and Solubility with eCPA

DEFF Research Database (Denmark)

Schlaikjer, Anders; Thomsen, Kaj; Kontogeorgis, Georgios

2017-01-01

with salt specific parameters. The focus is on accurate description of the salt solubility, and low deviation correlations are obtained for all salts investigated. The inclusion of the solubility data in the parametrization has, compared to parameters only parametrized to osmotic coefficients and activity...... coefficients, not significantly affected the deviations of the osmotic coefficients and activity coefficients. The average deviations of the activity coefficient does increase slightly and it was found that the increase in deviations was almost entirely due to reduced accuracy at high temperature and high...... molality. The model is, furthermore, compared to the activity coefficient model, Extended UNIQUAC. It is shown that the eCPA provides more accurate solubility description at higher temperatures than Extended UNIQUAC but also that Extended UNIQUAC is slightly better at describing the activity coefficients...

Recovery rates, enhanced oil recovery and technological limits.

Science.gov (United States)

Muggeridge, Ann; Cockin, Andrew; Webb, Kevin; Frampton, Harry; Collins, Ian; Moulds, Tim; Salino, Peter

2014-01-13

Enhanced oil recovery (EOR) techniques can significantly extend global oil reserves once oil prices are high enough to make these techniques economic. Given a broad consensus that we have entered a period of supply constraints, operators can at last plan on the assumption that the oil price is likely to remain relatively high. This, coupled with the realization that new giant fields are becoming increasingly difficult to find, is creating the conditions for extensive deployment of EOR. This paper provides a comprehensive overview of the nature, status and prospects for EOR technologies. It explains why the average oil recovery factor worldwide is only between 20% and 40%, describes the factors that contribute to these low recoveries and indicates which of those factors EOR techniques can affect. The paper then summarizes the breadth of EOR processes, the history of their application and their current status. It introduces two new EOR technologies that are beginning to be deployed and which look set to enter mainstream application. Examples of existing EOR projects in the mature oil province of the North Sea are discussed. It concludes by summarizing the future opportunities for the development and deployment of EOR.

Measuring device for the temperature coefficient of reactor moderators

International Nuclear Information System (INIS)

Nakano, Yuzo.

1987-01-01

Purpose: To rapidly determine by automatic calculation the temperature coefficient for moderators which has been determined so far by a log of manual processings. Constitution: Each of signals from a control rod position indicator, a reactor reactivity, instrument and moderator temperature meter are inputted, and each of the signals and designed valued for the doppler temperature coefficients are stored. Recurling calculation is conducted based on the reactivity and the moderator temperature at an interval where the temperature changes of the moderators are equalized at an identical control rod position, to determine isothermic coefficient. Then, the temperature coefficient for moderator are calculated from the isothermic coefficient and the doppler temperature coefficient. The relationship between the reactivity and the moderator temperature is plotted on a X-Y recorder. The stored signals and the calculated temperature coefficient for moderators are sequentially displayed and the results are printed out when the measurement is completed. According to the present device, since the real time processing is conducted, the processing time can be shortened remarkably. Accordingly, it is possible to save the man power for the test of the nuclear reactor and improve the reactor operation performance. (Kamimura, M.)

Non-linear Bayesian update of PCE coefficients

KAUST Repository

Litvinenko, Alexander

2014-01-06

Given: a physical system modeled by a PDE or ODE with uncertain coefficient q(?), a measurement operator Y (u(q), q), where u(q, ?) uncertain solution. Aim: to identify q(?). The mapping from parameters to observations is usually not invertible, hence this inverse identification problem is generally ill-posed. To identify q(!) we derived non-linear Bayesian update from the variational problem associated with conditional expectation. To reduce cost of the Bayesian update we offer a unctional approximation, e.g. polynomial chaos expansion (PCE). New: We apply Bayesian update to the PCE coefficients of the random coefficient q(?) (not to the probability density function of q).

Non-linear Bayesian update of PCE coefficients

KAUST Repository

Litvinenko, Alexander; Matthies, Hermann G.; Pojonk, Oliver; Rosic, Bojana V.; Zander, Elmar

2014-01-01

Given: a physical system modeled by a PDE or ODE with uncertain coefficient q(?), a measurement operator Y (u(q), q), where u(q, ?) uncertain solution. Aim: to identify q(?). The mapping from parameters to observations is usually not invertible, hence this inverse identification problem is generally ill-posed. To identify q(!) we derived non-linear Bayesian update from the variational problem associated with conditional expectation. To reduce cost of the Bayesian update we offer a unctional approximation, e.g. polynomial chaos expansion (PCE). New: We apply Bayesian update to the PCE coefficients of the random coefficient q(?) (not to the probability density function of q).

Non-vanishing of Taylor coefficients and Poincaré series

DEFF Research Database (Denmark)

O'Sullivan, C.; Risager, Morten S.

2013-01-01

We prove recursive formulas for the Taylor coefficients of cusp forms, such as Ramanujan's Delta function, at points in the upper half-plane. This allows us to show the non-vanishing of all Taylor coefficients of Delta at CM points of small discriminant as well as the non-vanishing of certain...... Poincaré series. At a "generic" point, all Taylor coefficients are shown to be non-zero. Some conjectures on the Taylor coefficients of Delta at CM points are stated....

Development of reflectance-based crop coefficients for corn

International Nuclear Information System (INIS)

Neale, C.M.U.; Bausch, W.C.; Heermann, D.F.

1989-01-01

Concurrent measurements of reflected canopy radiation and the basal crop coefficient (K^b) for corn were conducted throughout a season in order to develop a reflectance-based crop coefficient model. Reflectance was measured in Landsat Thematic Mapper bands TM3 (0.63 - 0.69 um) and TM4 (0.76 - 0.90 um) and used in the calculation of a vegetation index called the normalized difference (ND). A linear transformation of the ND was used as the reflectance-based crop coefficient (Kcr). The transformation equates the ND for dry bare soil and the ND at effective cover, to the basal crop coefficient for dry soil evaporation and at effective cover, respectively. Basal crop coefficient values for com were obtained from daily evapotranspiration measurements of corn and alfalfa, using hydraulic weighing lysimeters. The Richards growth curve function was fitted to both sets of data. The K^b values were determined to be within -2.6% and 4.7% of the K^^ values. The date of effective cover obtained from the K^b data was within four days of the date on which the ND curve reached its maxima according to the Richards function. A comparison of the Kcr with basal crop curves from the literature for several years of data indicated good agreement. Reflectance-based crop coefficients are sensitive to periods of slow and fast growth induced by weather conditions, resulting in a real time coefficient, independent from the traditional time base parameters based on the day of planting and effective cover

A new consistent definition of the homogenized diffusion coefficient of a lattice, limitations of the homogenization concept, and discussion of previously defined coefficients

International Nuclear Information System (INIS)

Deniz, V.C.

1980-01-01

The problem concerned with the correct definition of the homogenized diffusion coefficient of a lattice, and the concurrent problem of whether or not a homogenized diffusion equation can be formally set up, is studied by a space-energy-angle dependent treatment for a general lattice cell using an operator notation which applies to any eigen-problem. A new definition of the diffusion coefficient is given, which combines within itself the individual merits of the two definitions of Benoist. The relation between the new coefficient and the ''uncorrected'' Benoist coefficient is discussed by considering continuous-spectrum and multi-group diffusion equations. Other definitions existing in the literature are briefly discussed. It is concluded that a diffusion coefficient should represent only leakage effects. A comparison is made between the homogenization approach and the approach via eigen-coefficients, and brief indications are given of a possible scheme for the latter. (author)

Systematic Risk on Istanbul Stock Exchange: Traditional Beta Coefficient Versus Downside Beta Coefficient

Directory of Open Access Journals (Sweden)

Gülfen TUNA

2013-03-01

Full Text Available The aim of this study is to test the validity of Downside Capital Asset Pricing Model (D-CAPM on the ISE. At the same time, the explanatory power of CAPM's traditional beta and D-CAPM's downside beta on the changes in the average return values are examined comparatively. In this context, the monthly data for seventy three stocks that are continuously traded on the ISE for the period 1991-2009 is used. Regression analysis is applied in this study. The research results have shown that D-CAPM is valid on the ISE. In addition, it is obtained that the power of downside beta coefficient is higher than traditional beta coefficient on explaining the return changes. Therefore, it can be said that the downside beta is superior to traditional beta in the ISE for chosen period.

Experimental study on an innovative multifunction heat pipe type heat recovery two-stage sorption refrigeration system

International Nuclear Information System (INIS)

Li, T.X.; Wang, R.Z.; Wang, L.W.; Lu, Z.S.

2008-01-01

An innovative multifunction heat pipe type sorption refrigeration system is designed, in which a two-stage sorption thermodynamic cycle based on two heat recovery processes was employed to reduce the driving heat source temperature, and the composite sorbent of CaCl 2 and activated carbon was used to improve the mass and heat transfer performances. For this test unit, the heating, cooling and heat recovery processes between two reactive beds are performed by multifunction heat pipes. The aim of this paper is to investigate the cycled characteristics of two-stage sorption refrigeration system with heat recovery processes. The two sub-cycles of a two-stage cycle have different sorption platforms though the adsorption and desorption temperatures are equivalent. The experimental results showed that the pressure evolutions of two beds are nearly equivalent during the first stage, and desorption pressure during the second stage is large higher than that in the first stage while the desorption temperatures are same during the two operation stages. In comparison with conventional two-stage cycle, the two-stage cycle with heat recovery processes can reduce the heating load for desorber and cooling load for adsorber, the coefficient of performance (COP) has been improved more than 23% when both cycles have the same regeneration temperature of 103 deg. C and the cooling water temperature of 30 deg. C. The advanced two-stage cycle provides an effective method for application of sorption refrigeration technology under the condition of low-grade temperature heat source or utilization of renewable energy

Solving Variable Coefficient Fourth-Order Parabolic Equation by ...

African Journals Online (AJOL)

Solving Variable Coefficient Fourth-Order Parabolic Equation by Modified initial guess Variational ... variable coefficient fourth order parabolic partial differential equations. The new method shows rapid convergence to the exact solution.

Clustering coefficient and community structure of bipartite networks

Science.gov (United States)

Zhang, Peng; Wang, Jinliang; Li, Xiaojia; Li, Menghui; Di, Zengru; Fan, Ying

2008-12-01

Many real-world networks display natural bipartite structure, where the basic cycle is a square. In this paper, with the similar consideration of standard clustering coefficient in binary networks, a definition of the clustering coefficient for bipartite networks based on the fraction of squares is proposed. In order to detect community structures in bipartite networks, two different edge clustering coefficients LC4 and LC3 of bipartite networks are defined, which are based on squares and triples respectively. With the algorithm of cutting the edge with the least clustering coefficient, communities in artificial and real world networks are identified. The results reveal that investigating bipartite networks based on the original structure can show the detailed properties that is helpful to get deep understanding about the networks.

Measuring the Recovery Orientation of ACT

Science.gov (United States)

Salyers, Michelle P.; Stull, Laura G.; Rollins, Angela L.; McGrew, John H.; Hicks, Lia J.; Thomas, Dave; Strieter, Doug

2014-01-01

Background Approaches to measuring recovery orientation are needed, particularly for programs that may struggle with implementing recovery-oriented treatment. Objective A mixed methods comparative study was conducted to explore effective approaches to measuring recovery orientation of Assertive Community Treatment (ACT) teams. Design Two ACT teams exhibiting high and low recovery orientation were compared using surveys, treatment plan ratings, diaries of treatment visits, and team-leader-reported treatment control mechanisms. Results The recovery-oriented team differed on one survey measure (higher expectations for consumer recovery), treatment planning (greater consumer involvement and goal-directed content), and use of control mechanisms (less use of representative payee, agency-held lease, daily medication delivery, and family involvement). Staff and consumer diaries showed the most consistent differences (e.g., conveying hope and choice) and were the least susceptible to observer bias, but had the lowest response rates. Conclusions Several practices differentiate recovery orientation on ACT teams, and a mixed-methods assessment approach is feasible. PMID:23690285

Indium recovery by solvent extraction

International Nuclear Information System (INIS)

Fortes, Marilia Camargos Botelho

1999-04-01

Indium has been recovered as a byproduct from residues generated from the sulfuric acid leaching circuits in mineral plants for zinc recovery. Once its recovery comes from the slags of other metals recovery, it is necessary to separate it from the other elements which usually are present in high concentrations. Many works have been approaching this separation and indicate the solvent extraction process as the main technique used. In Brazilian case, indium recovery depends on the knowledge of this technique and its development. This paper describes the solvent extraction knowledge for the indium recovery from aqueous solutions generated in mineral plants. The results for determination of the best experimental conditions to obtain a high indium concentration solution and minimum iron poisoning by solvent extraction with di (2-ethylhexyl)-phosphoric acid (D2EHPA) solubilized in isoparafin and exxsol has been presented. (author)

Improved diffusion coefficients generated from Monte Carlo codes

International Nuclear Information System (INIS)

Herman, B. R.; Forget, B.; Smith, K.; Aviles, B. N.

2013-01-01

Monte Carlo codes are becoming more widely used for reactor analysis. Some of these applications involve the generation of diffusion theory parameters including macroscopic cross sections and diffusion coefficients. Two approximations used to generate diffusion coefficients are assessed using the Monte Carlo code MC21. The first is the method of homogenization; whether to weight either fine-group transport cross sections or fine-group diffusion coefficients when collapsing to few-group diffusion coefficients. The second is a fundamental approximation made to the energy-dependent P1 equations to derive the energy-dependent diffusion equations. Standard Monte Carlo codes usually generate a flux-weighted transport cross section with no correction to the diffusion approximation. Results indicate that this causes noticeable tilting in reconstructed pin powers in simple test lattices with L2 norm error of 3.6%. This error is reduced significantly to 0.27% when weighting fine-group diffusion coefficients by the flux and applying a correction to the diffusion approximation. Noticeable tilting in reconstructed fluxes and pin powers was reduced when applying these corrections. (authors)

The influence of hydrogen bonding on partition coefficients

Science.gov (United States)

Borges, Nádia Melo; Kenny, Peter W.; Montanari, Carlos A.; Prokopczyk, Igor M.; Ribeiro, Jean F. R.; Rocha, Josmar R.; Sartori, Geraldo Rodrigues

2017-02-01

This Perspective explores how consideration of hydrogen bonding can be used to both predict and better understand partition coefficients. It is shown how polarity of both compounds and substructures can be estimated from measured alkane/water partition coefficients. When polarity is defined in this manner, hydrogen bond donors are typically less polar than hydrogen bond acceptors. Analysis of alkane/water partition coefficients in conjunction with molecular electrostatic potential calculations suggests that aromatic chloro substituents may be less lipophilic than is generally believed and that some of the effect of chloro-substitution stems from making the aromatic π-cloud less available to hydrogen bond donors. Relationships between polarity and calculated hydrogen bond basicity are derived for aromatic nitrogen and carbonyl oxygen. Aligned hydrogen bond acceptors appear to present special challenges for prediction of alkane/water partition coefficients and this may reflect `frustration' of solvation resulting from overlapping hydration spheres. It is also shown how calculated hydrogen bond basicity can be used to model the effect of aromatic aza-substitution on octanol/water partition coefficients.

Correlation Coefficients: Appropriate Use and Interpretation.

Science.gov (United States)

Schober, Patrick; Boer, Christa; Schwarte, Lothar A

2018-05-01

Correlation in the broadest sense is a measure of an association between variables. In correlated data, the change in the magnitude of 1 variable is associated with a change in the magnitude of another variable, either in the same (positive correlation) or in the opposite (negative correlation) direction. Most often, the term correlation is used in the context of a linear relationship between 2 continuous variables and expressed as Pearson product-moment correlation. The Pearson correlation coefficient is typically used for jointly normally distributed data (data that follow a bivariate normal distribution). For nonnormally distributed continuous data, for ordinal data, or for data with relevant outliers, a Spearman rank correlation can be used as a measure of a monotonic association. Both correlation coefficients are scaled such that they range from -1 to +1, where 0 indicates that there is no linear or monotonic association, and the relationship gets stronger and ultimately approaches a straight line (Pearson correlation) or a constantly increasing or decreasing curve (Spearman correlation) as the coefficient approaches an absolute value of 1. Hypothesis tests and confidence intervals can be used to address the statistical significance of the results and to estimate the strength of the relationship in the population from which the data were sampled. The aim of this tutorial is to guide researchers and clinicians in the appropriate use and interpretation of correlation coefficients.

Membrane mobility and microdomain association of the dopamine transporter studied with fluorescence correlation spectroscopy and fluorescence recovery after photobleaching

DEFF Research Database (Denmark)

Adkins, Erika M; Samuvel, Devadoss J; Fog, Jacob U

2007-01-01

To investigate microdomain association of the dopamine transporter (DAT), we employed FCS (fluorescence correlation spectroscopy) and FRAP (fluorescence recovery after photobleaching). In non-neuronal cells (HEK293), FCS measurements revealed for the YFP-DAT (DAT tagged with yellow fluorescent...... protein) a diffusion coefficient (D) of approximately 3.6 x 10(-9) cm2/s, consistent with a relatively freely diffusible protein. In neuronally derived cells (N2a), we were unable to perform FCS measurements on plasma membrane-associated protein due to photobleaching, suggesting partial immobilization...

Amide temperature coefficients in the protein G B1 domain

International Nuclear Information System (INIS)

Tomlinson, Jennifer H.; Williamson, Mike P.

2012-01-01

Temperature coefficients have been measured for backbone amide 1 H and 15 N nuclei in the B1 domain of protein G (GB1), using temperatures in the range 283–313 K, and pH values from 2.0 to 9.0. Many nuclei display pH-dependent coefficients, which were fitted to one or two pK a values. 1 H coefficients showed the expected behaviour, in that hydrogen-bonded amides have less negative values, but for those amides involved in strong hydrogen bonds in regular secondary structure there is a negative correlation between strength of hydrogen bond and size of temperature coefficient. The best correlation to temperature coefficient is with secondary shift, indicative of a very approximately uniform thermal expansion. The largest pH-dependent changes in coefficient are for amides in loops adjacent to sidechain hydrogen bonds rather than the amides involved directly in hydrogen bonds, indicating that the biggest determinant of the temperature coefficient is temperature-dependent loss of structure, not hydrogen bonding. Amide 15 N coefficients have no clear relationship with structure.

Personality and recovery: integrating personality assessment data to facilitate the recovery process.

Science.gov (United States)

Donat, D C

2001-01-01

The relatively enduring and persistent nature of personality traits means that they will likely continue to impact the course of psychiatric recovery after Axis I symptoms are stabilized. These traits can significantly impact the choices that recovering persons make and the quality of interpersonal relationships with care providers who are trying to facilitate the recovery process. Despite this, they are often inadequately assessed and considered in providing psychiatric care. This manuscript reviews the common combinations of personality traits that have emerged across a variety of clinical samples. The implications of these personality features for the provision of care in an inpatient setting to facilitate recovery are discussed.

Reference-free determination of tissue absorption coefficient by modulation transfer function characterization in spatial frequency domain.

Science.gov (United States)

Chen, Weiting; Zhao, Huijuan; Li, Tongxin; Yan, Panpan; Zhao, Kuanxin; Qi, Caixia; Gao, Feng

2017-08-08

Spatial frequency domain (SFD) measurement allows rapid and non-contact wide-field imaging of the tissue optical properties, thus has become a potential tool for assessing physiological parameters and therapeutic responses during photodynamic therapy of skin diseases. The conventional SFD measurement requires a reference measurement within the same experimental scenario as that for a test one to calibrate mismatch between the real measurements and the model predictions. Due to the individual physical and geometrical differences among different tissues, organs and patients, an ideal reference measurement might be unavailable in clinical trials. To address this problem, we present a reference-free SFD determination of absorption coefficient that is based on the modulation transfer function (MTF) characterization. Instead of the absolute amplitude that is used in the conventional SFD approaches, we herein employ the MTF to characterize the propagation of the modulated lights in tissues. With such a dimensionless relative quantity, the measurements can be naturally corresponded to the model predictions without calibrating the illumination intensity. By constructing a three-dimensional database that portrays the MTF as a function of the optical properties (both the absorption coefficient μ a and the reduced scattering coefficient [Formula: see text]) and the spatial frequency, a look-up table approach or a least-square curve-fitting method is readily applied to recover the absorption coefficient from a single frequency or multiple frequencies, respectively. Simulation studies have verified the feasibility of the proposed reference-free method and evaluated its accuracy in the absorption recovery. Experimental validations have been performed on homogeneous tissue-mimicking phantoms with μ a ranging from 0.01 to 0.07 mm -1 and [Formula: see text] = 1.0 or 2.0 mm -1 . The results have shown maximum errors of 4.86 and 7% for [Formula: see text] = 1.0 mm -1 and

Kinetic theory of the interdiffusion coefficient in dense plasmas

International Nuclear Information System (INIS)

Boercker, D.B.

1986-08-01

Naive applications of Spitzer's theory to very dense plasmas can lead to negative diffusion coefficients. The interdiffusion coefficients in Binary Ionic Mixtures (two species of point ions in a uniform neutralizing background) have been calculated recently using molecular dynamics techniques. These calculations can provide useful benchmarks for theoretical evaluations of the diffusion coefficient in dense plasma mixtures. This paper gives a brief description of a kinetic theoretic approximation to the diffusion coefficient which generalizes Spitzer to high density and is in excellent agreement with the computer simulations. 15 refs., 1 fig., 2 tabs

Addiction recovery: its definition and conceptual boundaries.

Science.gov (United States)

White, William L

2007-10-01

The addiction field's failure to achieve consensus on a definition of "recovery" from severe and persistent alcohol and other drug problems undermines clinical research, compromises clinical practice, and muddles the field's communications to service constituents, allied service professionals, the public, and policymakers. This essay discusses 10 questions critical to the achievement of such a definition and offers a working definition of recovery that attempts to meet the criteria of precision, inclusiveness, exclusiveness, measurability, acceptability, and simplicity. The key questions explore who has professional and cultural authority to define recovery, the defining ingredients of recovery, the boundaries (scope and depth) of recovery, and temporal benchmarks of recovery (when recovery begins and ends). The process of defining recovery touches on some of the most controversial issues within the addictions field.

Higher-order Cn dispersion coefficients for hydrogen

International Nuclear Information System (INIS)

Mitroy, J.; Bromley, M.W.J.

2005-01-01

The complete set of second-, third-, and fourth-order van der Waals coefficients C n up to n=32 for the H(1s)-H(1s) dimer have been determined. They are computed by diagonalizing the nonrelativistic Hamiltonian for hydrogen to obtain a set of pseudostates that are used to evaluate the appropriate sum rules. A study of the convergence pattern for n≤16 indicates that all the C n/16 coefficients are accurate to 13 significant digits. The relative size of the fourth-order C n (4) to the second-order C n (2) coefficients is seen to increase as n increases and at n=32 the fourth-order term is actually larger

Determination of beta attenuation coefficients by means of timing method

International Nuclear Information System (INIS)

Ermis, E.E.; Celiktas, C.

2012-01-01

Highlights: ► Beta attenuation coefficients of absorber materials were found in this study. ► For this process, a new method (timing method) was suggested. ► The obtained beta attenuation coefficients were compatible with the results from the traditional one. ► The timing method can be used to determine beta attenuation coefficient. - Abstract: Using a counting system with plastic scintillation detector, beta linear and mass attenuation coefficients were determined for bakelite, Al, Fe and plexiglass absorbers by means of timing method. To show the accuracy and reliability of the obtained results through this method, the coefficients were also found via conventional energy method. Obtained beta attenuation coefficients from both methods were compared with each other and the literature values. Beta attenuation coefficients obtained through timing method were found to be compatible with the values obtained from conventional energy method and the literature.

Mortality, recovery, and community shifts of scleractinian corals in Puerto Rico one decade after the 2005 regional bleaching event.

Science.gov (United States)

García-Sais, Jorge R; Williams, Stacey M; Amirrezvani, Ali

2017-01-01

This work analyzes the mortality, recovery, and shifts in the composition of scleractinian corals from Puerto Rico one decade after the 2005 regional coral bleaching event. Temporal and spatial patterns of coral community structure were examined using a stratified, non-random sampling approach based on five permanent transects per reef at 16 reef stations. A negative correlation between percent coral cover loss and light attenuation coefficient (Kd 490 ) was observed, suggesting that light attenuation, as influenced by water turbidity and depth, played a major role in coral protection during the bleaching event ("sunblock effect"). Responses of coral assemblages varied after the bleaching event, including shifts of cover from massive corals ( Orbicella spp.) to opportunistic ( Porites astreoides ) and branching corals ( Madracis auretenra , P. porites ) and/or turf algae; partial recovery of reef substrate cover by O. annularis complex; and no measurable changes in coral assemblages before and after the event.

Cognitive performance and aphasia recovery.

Science.gov (United States)

Fonseca, José; Raposo, Ana; Martins, Isabel Pavão

2018-03-01

Objectives This study assessed cognitive performance of subjects with aphasia during the acute stage of stroke and evaluated how such performance relates to recovery at 3 months. Materials & methods Patients with aphasia following a left hemisphere stroke were evaluated during the first (baseline) and the fourth-month post onset. Assessment comprised non-verbal tests of attention/processing speed (Symbol Search, Cancelation Task), executive functioning (Matrix Reasoning, Tower of Hanoi, Clock Drawing, Motor Initiative), semantic (Camel and Cactus Test), episodic and immediate memory (Memory for Faces Test, 5 Objects Memory Test, and Spatial Span. Recovery was measured by the Token Test score at 3 months. The impact of baseline performance on recovery was evaluated by logistic regression adjusting for age, education, severity of aphasia and the Alberta Stroke Program Early CT (ASPECT) score. Results Thirty-nine subjects (with a mean of 66.5 ± 10.6 years of age, 17 men) were included. Average baseline cognitive performance was within normal range in all tests except in memory tests (semantic, episodic and immediate memory) for which scores were ≤-1.5sd. Subjects with poor aphasia recovery (N = 27) were older and had fewer years of formal education but had identical ASPECT score compared to those with favorable recovery. Considering each test individually, the score obtained on the Matrix Reasoning test was the only one to predict aphasia recovery (Exp(B)=24.085 p = 0.038). Conclusions The Matrix Reasoning Test may contribute to predict aphasia recovery. Cognitive performance is a measure of network disruption but may also indicate the availability of recovery strategies.

Mayer coefficients in two-dimensional Coulomb systems

International Nuclear Information System (INIS)

Speer, E.R.

1986-01-01

It is shown that, for neutral systems of particles of arbitrary charges in two dimensions, with hard cores, coefficients of the Mayer series for the pressure exist in the thermodynamic limit below certain thresholds in the temperature. The methods used here apply also to correlation functions and yield bounds on the asymptotic behavior of their Mayer coefficients

Helioseismic Solar Cycle Changes and Splitting Coefficients

Indian Academy of Sciences (India)

tribpo

Abstract. Using the GONG data for a period over four years, we have studied the variation of frequencies and splitting coefficients with solar cycle. Frequencies and even-order coefficients are found to change signi- ficantly with rising phase of the solar cycle. We also find temporal varia- tions in the rotation rate near the solar ...

Illness management and recovery

DEFF Research Database (Denmark)

Dalum, Helle Stentoft; Waldemar, Anna Kristine; Korsbek, Lisa

2018-01-01

OBJECTIVE: Illness Management and Recovery (IMR) is a psychosocial intervention with a recovery-oriented approach. The program has been evaluated in different settings; however evidence for the effects of IMR is still deficient. The aim of this trial was to investigate the benefits and harms...

Changes in Electrokinetic Coupling Coefficients of Granite under Triaxial Deformation

Directory of Open Access Journals (Sweden)

Osamu Kuwano

2012-01-01

Full Text Available Electrokinetic phenomena are believed to be the most likely origin of electromagnetic signals preceding or accompanying earthquakes. The intensity of the source current due to the electrokinetic phenomena is determined by the fluid flux and the electrokinetic coupling coefficient called streaming current coefficient; therefore, how the coefficient changes before rupture is essential. Here, we show how the electrokinetic coefficients change during the rock deformation experiment up to failure. The streaming current coefficient did not increase before failure, but continued to decrease up to failure, which is explained in terms of the elastic closure of capillary. On the other hand, the streaming potential coefficient, which is the product of the streaming current coefficient and bulk resistivity of the rock, increased at the onset of dilatancy. It may be due to change in bulk resistivity. Our result indicates that the zeta potential of the newly created surface does not change so much from that of the preexisting fluid rock interface.

Reaction rate calculations via transmission coefficients

International Nuclear Information System (INIS)

Feit, M.D.; Alder, B.J.

1985-01-01

The transmission coefficient of a wavepacket traversing a potential barrier can be determined by steady state calculations carried out in imaginary time instead of by real time dynamical calculations. The general argument is verified for the Eckart barrier potential by a comparison of transmission coefficients calculated from real and imaginary time solutions of the Schroedinger equation. The correspondence demonstrated here allows a formulation for the reaction rate that avoids difficulties due to both rare events and explicitly time dependent calculations. 5 refs., 2 figs

Dual-earner couples' weekend recovery support, state of recovery, and work engagement: Work-linked relationship as a moderator.

Science.gov (United States)

Park, YoungAh; Haun, Verena C

2017-10-01

Despite growing recovery research, little is known about couple-dyadic processes of recovery from work. Given that dual-earner couples experience most of their recovery opportunities during nonwork times when they are together, partners in a couple relationship may substantially affect recovery and work engagement. In this study, we propose a couple-dyadic model in which weekend partner recovery support (reported by the recipient partner) is positively related to the recipient partner's state of recovery after the weekend which, in turn, increases the recipient's work engagement the following week (actor-actor mediation effect). We also test the effect of one's state of recovery on the partner's subsequent work engagement (partner effect). Additionally, work-linked relationship status is tested as a moderator of the partner effect. Actor-partner interdependence mediation modeling is used to analyze the data from 167 dual-earner couples who answered surveys on 4 measurement occasions. The results support the indirect effect of partner recovery support on work engagement through the postweekend state of recovery. Multigroup analysis results reveal that the partner effect of state of recovery on work engagement is significant for work-linked couples only and is absent for non-work-linked couples. Theoretical and practical implications, limitations, and future research directions are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Measuring individual disaster recovery: a socioecological framework.

Science.gov (United States)

Abramson, David M; Stehling-Ariza, Tasha; Park, Yoon Soo; Walsh, Lauren; Culp, Derrin

2010-09-01

Disaster recovery is a complex phenomenon. Too often, recovery is measured in singular fashion, such as quantifying rebuilt infrastructure or lifelines, without taking in to account the affected population's individual and community recovery. A comprehensive framework is needed that encompasses a much broader and far-reaching construct with multiple underlying dimensions and numerous causal pathways; without the consideration of a comprehensive framework that investigates relationships between these factors, an accurate measurement of recovery may not be valid. This study proposes a model that encapsulates these ideas into a single framework, the Socio-Ecological Model of Recovery. Using confirmatory factor analysis, an operational measure of recovery was developed and validated using the five measures of housing stability, economic stability, physical health, mental health, and social role adaptation. The data were drawn from a sample of displaced households following Hurricane Katrina. Measures of psychological strength, risk, disaster exposure, neighborhood contextual effects, and formal and informal help were modeled to examine their direct and indirect effects on recovery using a structural equation model. All five elements of the recovery measure were positively correlated with a latent measure of recovery, although mental health and social role adaptation displayed the strongest associations. An individual's psychological strength had the greatest association with positive recovery, followed by having a household income greater than $20,000 and having informal social support. Those factors most strongly associated with an absence of recovery included the time displaced since the hurricane, being disabled, and living in a community with substantial social disorder. The socio-ecological framework provides a robust means for measuring recovery, and for testing those factors associated with the presence or absence of recovery.

Effect of rolling motion on the expansion and contraction loss coefficients

International Nuclear Information System (INIS)

Yan, B.H.; Gu, H.Y.

2013-01-01

Highlights: ► The expansion and contraction loss coefficients in rolling motion are analyzed. ► Effects of rolling motion on the expansion and contraction loss coefficients are different. ► The spanwise and transverse additional forces contribute slightly to the local loss. ► The oscillations of loss coefficients increase as the strengthening of rolling motion. - Abstract: The sudden expansion and sudden contraction loss coefficients in rolling motion are investigated with CFD code FLUENT. The calculation results are validated with experimental and theoretical results in steady state. The effects of rolling motion on the expansion and contraction loss coefficients are different. The effects of spanwise and transverse additional forces on the expansion and contraction loss coefficients are weak. The effect of velocity oscillation on the contraction loss coefficient is more significant than that on the expansion loss coefficient. The oscillation of local loss coefficient also becomes more and more irregular as the strengthening of rolling motion

Theoretical investigation of the extinction coefficient of magnetic fluid

Energy Technology Data Exchange (ETDEWEB)

Fang Xiaopeng; Xuan Yimin, E-mail: ymxuan@mail.njust.edu.cn; Li Qiang [Nanjing University of Science and Technology, School of Energy and Power Engineering (China)

2013-05-15

A new theoretical approach for calculating the extinction coefficient of magnetic fluid is proposed, which is based on molecular dynamics (MD) simulation and T-matrix method. By means of this approach, the influence of particle diameter, particle volume fraction, and external magnetic filed on the extinction coefficient of magnetic fluid is investigated. The results show that the extinction coefficient of the magnetic fluid linearly increases with increase in the particle volume fraction. For a given particle volume fraction, the extinction coefficient increases with increase in the particle diameter which varies from 5 to 20 nm. When a uniform external magnetic filed is applied to the magnetic fluid, the extinction coefficient of the magnetic fluid presents an anisotropic feature. These results agree well with the reported experimental results. The proposed approach is applicable to investigating the optical properties of magnetic fluids.

Technique for Determining Lock Coefficient of Differential "Quif"

Directory of Open Access Journals (Sweden)

A. B. Fominyh

2015-01-01

Full Text Available Increasing the traction qualities of cars on the black ice and snow-covered roads is a relevant task. There are two ways to solve this task, i.e. optimize distribution of the power stream between the driving wheels of the car; introduce a differential (differentials of the increased friction in transmission.Now, an installation of the increased friction differential in transmission is the most widespread measure to increase traction properties of cars. The differential of design "Quif" is one of such differentials. To estimate the efficiency degree of using such a differential is possible either experimentally or theoretically. In case of theoretically determined usefulness of this differential design, as an estimate indicator of the differential installation in transmission a coefficient of lock is accepted.The article considers an algorithm and a technique to calculate a lock coefficient of the differential design "Quif" allowing us to define numeric values of the lock coefficient of such differential at designing stage. It also considers how the lock coefficient depends on the gearing angle and tilt angle of the gear wheel teeth of differential. The given estimating algorithm of designated parameter of differential has more logical and compact structure with regard to the known ones. The lock coefficient values calculated by the offered technique differ from the experimental data by no more than 12%. Taking into account abovementioned, the presented technique for calculating lock coefficient of differential "Quif" is advisable for practical application.

Tritium recovery from co-deposited layers using 193-nm laser

Science.gov (United States)

Shu, W. M.; Kawakubo, Y.; Nishi, M. F.

Recovery of tritium from co-deposited layers formed in deuterium-tritium plasma operations of the TFTR (Tokamak Fusion Test Reactor) was investigated by the use of an ArF excimer laser operating at the wavelength of 193 nm. At the laser energy density of 0.1 J/cm2, a transient spike of the tritium-release rate was observed at initial irradiation. Hydrogen isotopes were released in the form of hydrogen-isotope molecules during the laser irradiation in vacuum, suggesting that tritium can be recovered readily from the released gases. In a second experiment, hydrogen (tritium) recovery from the co-deposited layers on JT-60 tiles that had experienced hydrogen-plasma operations was investigated by laser ablation with a focused beam of the excimer laser. The removal rate of the co-deposited layers was quite low when the laser energy density was smaller than the ablation threshold (1.0 J/cm2), but reached 1.1 μm/pulse at the laser energy density of 7.6 J/cm2. The effective absorption coefficient in the co-deposited layers at the laser wavelength was determined to be 1.9 μm-1. The temperature of the surface during the irradiation at the laser energy density of 0.5 J/cm2 was measured on the basis of Planck's law of radiation, and the maximum temperature during the irradiation decreased from 3570 K at the initial irradiation to 2550 K at the 1000th pulse of the irradiation.

Reactor kinetics revisited: a coefficient based model (CBM)

International Nuclear Information System (INIS)

Ratemi, W.M.

2011-01-01

In this paper, a nuclear reactor kinetics model based on Guelph expansion coefficients calculation ( Coefficients Based Model, CBM), for n groups of delayed neutrons is developed. The accompanying characteristic equation is a polynomial form of the Inhour equation with the same coefficients of the CBM- kinetics model. Those coefficients depend on Universal abc- values which are dependent on the type of the fuel fueling a nuclear reactor. Furthermore, such coefficients are linearly dependent on the inserted reactivity. In this paper, the Universal abc- values have been presented symbolically, for the first time, as well as with their numerical values for U-235 fueled reactors for one, two, three, and six groups of delayed neutrons. Simulation studies for constant and variable reactivity insertions are made for the CBM kinetics model, and a comparison of results, with numerical solutions of classical kinetics models for one, two, three, and six groups of delayed neutrons are presented. The results show good agreements, especially for single step insertion of reactivity, with the advantage of the CBM- solution of not encountering the stiffness problem accompanying the numerical solutions of the classical kinetics model. (author)

Teaching recovery to medical students.

LENUS (Irish Health Repository)

Feeney, Larkin

2013-03-01

Community mental health services are evolving toward more holistic, patient-centered, recovery-based practices. This change necessitates an attitudinal shift from mental health workers, and training in recovery principles is helpful in achieving this change. Medical students often have narrow, doctor-centered concepts of mental health care. Traditional clinical placements in psychiatry do little to address this. We evaluated a recovery-focused teaching program for medical students in psychiatry.

Riesz Frames and Approximation of the Frame Coefficients

DEFF Research Database (Denmark)

Christensen, Ole

1996-01-01

A frame is a familyof elements in a Hilbert space with the propertythat every element in the Hilbert space can be written as a (infinite)linear combination of the frame elements. Frame theory describes howone can choose the corresponding coefficients, which are calledframe coefficients. From...... the mathematical point of view this isgratifying, but for applications it is a problem that the calculationrequires inversion of an operator on the Hilbert space.The projection method is introduced in order to avoid this problem.The basic idea is to consider finite subfamiliesof the frame and the orthogonal...... projection onto its span. Forfin QTR H,P_nf has a representation as a linear combinationof f_i,i=1,2,..,n, and the corresponding coefficients can be calculatedusing finite dimensional methods. We find conditions implying that thosecoefficients converge to the correct frame coefficients as n goes...

[Electroencephalogram Feature Selection Based on Correlation Coefficient Analysis].

Science.gov (United States)

Zhou, Jinzhi; Tang, Xiaofang

2015-08-01

In order to improve the accuracy of classification with small amount of motor imagery training data on the development of brain-computer interface (BCD systems, we proposed an analyzing method to automatically select the characteristic parameters based on correlation coefficient analysis. Throughout the five sample data of dataset IV a from 2005 BCI Competition, we utilized short-time Fourier transform (STFT) and correlation coefficient calculation to reduce the number of primitive electroencephalogram dimension, then introduced feature extraction based on common spatial pattern (CSP) and classified by linear discriminant analysis (LDA). Simulation results showed that the average rate of classification accuracy could be improved by using correlation coefficient feature selection method than those without using this algorithm. Comparing with support vector machine (SVM) optimization features algorithm, the correlation coefficient analysis can lead better selection parameters to improve the accuracy of classification.

Mass: Fortran program for calculating mass-absorption coefficients

International Nuclear Information System (INIS)

Nielsen, Aa.; Svane Petersen, T.

1980-01-01

Determinations of mass-absorption coefficients in the x-ray analysis of trace elements are an important and time consuming part of the arithmetic calculation. In the course of time different metods have been used. The program MASS calculates the mass-absorption coefficients from a given major element analysis at the x-ray wavelengths normally used in trace element determinations and lists the chemical analysis and the mass-absorption coefficients. The program is coded in FORTRAN IV, and is operational on the IBM 370/165 computer, on the UNIVAC 1110 and on PDP 11/05. (author)

Variable-coefficient nonisospectral Toda lattice hierarchy and its ...

Indian Academy of Sciences (India)

In this paper, a hierarchy of nonisospectral equations with variable coefficients is derived from the ..... from the definitions of Lax integrability and Lax pairs [26] that the variable-coefficient ..... studying which will be the topic for our future study.

Perceptions about recovery needs and drug-avoidance recovery behaviors among youth in substance abuse treatment.

Science.gov (United States)

Gonzales, Rachel; Anglin, M Douglas; Glik, Deborah C; Zavalza, Christina

2013-01-01

This study used mixed methods to explore youth attitudes about recovery-related needs and important drug-avoidance behaviors after treatment. Focus groups were conducted with 118 substance using youth in treatment (four residential and 10 outpatient settings) throughout Los Angeles County. The average age was 17.4 (SD = 2.9); 78.3% were male, 66.1% Latino; and most were in treatment for primary marijuana (40.9%) or methamphetamine (30.4%) abuse. Quantitatve results from the drug-avoidance activity survey identified the following factors youth rated as important to their recovery after treatment: lifestyle improvement activities (95.7%); changing personal drug behaviors (89.6%); drug environment/culture change activities (82.5%); with the least important being therapeutic activities (78.5%). Qualitative findings from focus groups that asked what youth think are important for recovery programs to address after treatment revealed the following four areas: (1) recovery promotion to developmentally appropriate activities (95%); (2) facilitating the use of coping skills to deal with stress (85%); (3) offering alternative recovery support options (not just abstinence only) (75%); and (4) continuing to provide substance use education (65%). Findings highlight essential aspects of recovery in terms of need and drug-avoidance behaviors considered important to youth in treatment. Such information will help to better address clinical and recovery support models aimed at relapse prevention to ensure that the perceived problems of substance-abusing youth are adequately met.

Diffusion coefficients in 4-component mixture expressed explicitly in terms of binary diffusion coefficients and mole fractions

International Nuclear Information System (INIS)

Furuta, Hiroshi; Yamamoto, Ichiro

1996-01-01

Diffusion coefficients in 4-component mixture D ij (4) were expressed explicitly in terms of binary diffusion coefficients and mole fractions by solving a ratio of determinants defined by Hirschfelder et al. The explicit expressions of D ij (4) were divided into two terms, a term due to the i-j pairs of attention and a term common to all the pairs out of the 4 components. The two terms of D ij (4) had extended structures similar to corresponding those of D ij (3) respectively. (author)

Transfer of risk coefficients across populations

International Nuclear Information System (INIS)

Rasmussen, L.R.

1992-01-01

The variation of lifetime risk projections for a Canadian population caused by the uncertainty in the choice of method for transferring excess relative risk coefficients between populations is assessed. Site-specific projections, varied by factors up to 3.5 when excess risk coefficients of the BEIR V relative risk models were transferred to the Canadian population using an additive and multiplicative method. When the risk from all cancers are combined, differences between transfer methods were no longer significant. The Canadian projections were consistent with the ICRP-60 nominal fatal cancer risk estimates. (author)

Recovery of personal neglect.

Science.gov (United States)

Iosa, Marco; Guariglia, Cecilia; Matano, Alessandro; Paolucci, Stefano; Pizzamiglio, Luigi

2016-12-01

Extrapersonal unilateral spatial neglect after stroke is associated to a poor rehabilitation outcome. Minor attention has been paid to the recovery of personal neglect, to its relationship with the recovery of extrapersonal neglect and of independency in activities of daily living. The present study aims at evaluating whether there is an association between recovery of extrapersonal and personal neglect. The secondary aim was to investigate if personal neglect may affect the effectiveness of neurorehabilitation in patients with subacute stroke. Observational study. Neurorehabilitation Hospital in Rome, Italy, inpatients. A sample of 49 patients with unilateral spatial neglect resulting from right ischemic cerebral infarction was enrolled in this study, divided into three subgroups according to the presence and the degree of personal neglect, and evaluated pre and postneurorehabilitation. Personal neglect was evaluated using Zoccolotti and Judica's Scale, extrapersonal neglect using Letter Cancellation Test, Barrage Test, Sentence Reading Test and Wundt-Jastrow Area Illusion Test. Barthel Index (BI), Rivermead Mobility Index, and Canadian Neurological Scale were also administered. Results showed the following: 1) recovery of personal neglect was not significantly correlated with that of extrapersonal neglect, despite both the disorders were ameliorated after a "non-specific" rehabilitation treatment; 2) personal neglect per se was not an additional negative prognostic factor in the rehabilitation findings. Our results suggested that the recoveries of the two types of neglect are independent from each other, and that the presence of personal neglect does not imply significant additional problems to the functional outcomes. Our study highlighted the need of novel tools to assess the presence and to improve the recovery of personal neglect.

Absorption coefficients of silicon: A theoretical treatment

Science.gov (United States)

Tsai, Chin-Yi

2018-05-01

A theoretical model with explicit formulas for calculating the optical absorption and gain coefficients of silicon is presented. It incorporates direct and indirect interband transitions and considers the effects of occupied/unoccupied carrier states. The indirect interband transition is calculated from the second-order time-independent perturbation theory of quantum mechanics by incorporating all eight possible routes of absorption or emission of photons and phonons. Absorption coefficients of silicon are calculated from these formulas. The agreements and discrepancies among the calculated results, the Rajkanan-Singh-Shewchun (RSS) formula, and Green's data are investigated and discussed. For example, the RSS formula tends to overestimate the contributions of indirect transitions for cases with high photon energy. The results show that the state occupied/unoccupied effect is almost negligible for silicon absorption coefficients up to the onset of the optical gain condition where the energy separation of Quasi-Femi levels between electrons and holes is larger than the band-gap energy. The usefulness of using the physics-based formulas, rather than semi-empirical fitting ones, for absorption coefficients in theoretical studies of photovoltaic devices is also discussed.

Substances stimulating recovery for radiation injury

Energy Technology Data Exchange (ETDEWEB)

Takeda, A; Yonezawa, M; Katoh, N [Radiation Center of Osaka Prefecture, Sakai (Japan)

1978-11-01

A relationship between radiation injury and its recovery (intracellular recovery, intercellular recovery, or individual recovery) was discussed. In addition to histological researches in Japan, some substances (free radicals, endotoxin, vaccine, crude drugs, tissue extracts, blood platelet, etc.) stimulating recovery for radiation injury were introduced, and the progress of the study by the authors was summarized. Effects of a root of Panax ginseng (it is believed to accelerate segmentation of marrow cells, and synthesis of DNA and protein in rats and men), methods of its extracting and administration, its influences upon hemogram and organ weight in animal experiments, exclusion of side effects, period of administration, and purification of its effective components were reported.

Recovery of oil from underground drill sites

International Nuclear Information System (INIS)

Streeter, W.S.; Hutchinson, T.S.; Ameri, S.; Wasson, J.A.; Aminian, K.

1991-01-01

This paper reports that a significant quantity of oil is left in reservoirs after conventional oil recovery techniques have been applied. In West Virginia and Pennsylvania alone, this oil has been estimated at over 4.5 billion barrels (0.72 billion m 3 ). Conventional recovery methods are already being used when applicable. But a new recovery method is needed for use in reservoirs that have been abandoned. One alternative method for recovery of the residual oil is known as oil recovery from underground drill sites. This recovery technology is a combination of proven methods and equipment from the petroleum, mining, and civil construction industries. Underground oil recovery can be an economically viable method of producing oil. This has been shown in producing fields, field tests, and feasibility, studies. Faced with decreasing domestic oil production, the petroleum industry should give serious consideration to the use of oil recovery from underground drill sites as a safe, practical, and environmentally sensitive alternative method of producing oil from many reservoirs

The Stigma of Mental Illness and Recovery.

Science.gov (United States)

Avdibegović, Esmina; Hasanović, Mevludin

2017-12-01

Stigma and recovery "from" and "in" mental illness are associated in many various ways. While recovery gives opportunities, makes person stronger, gives purpose and meaning to their lives and leads to social inclusion, in the same time stigma reduces opportunities, reduces self-esteem and self-efficacy, reduces the belief in own abilities and contributes to social exclusion through discrimination. The recovery of a person with mental illness means to get and keep hope, to understand their own possibilities and impossibilities, active living, to be autonomous, to have a social identity and to give meaning and purpose of our own lives. The care system, recovery-oriented, provides help and support to people with mental disorders in his/her recovery, which contributes to reduction of self-stigma, to the elimination of stigmatizing attitudes and beliefs in mental health services which consequently may have a positive reflection in reducing the stigma of mental illness in the community. It is important to look at the stigma and recovery from the perspective of individual experience of each person with a mental illness in the process of recovery. A support to the recovery concept and the development of a recovery-oriented system of care should be one of the key segments of any strategy to combat the stigma of mental illness. Also, the cultural and the social stigma aspects of stigma would be taken into account in the developing of the recovery concept and on the recovery-oriented care system.

Recovery and Performance in Sport: Consensus Statement.

Science.gov (United States)

Kellmann, Michael; Bertollo, Maurizio; Bosquet, Laurent; Brink, Michel; Coutts, Aaron J; Duffield, Rob; Erlacher, Daniel; Halson, Shona L; Hecksteden, Anne; Heidari, Jahan; Kallus, K Wolfgang; Meeusen, Romain; Mujika, Iñigo; Robazza, Claudio; Skorski, Sabrina; Venter, Ranel; Beckmann, Jürgen

2018-02-01

The relationship between recovery and fatigue and its impact on performance has attracted the interest of sport science for many years. An adequate balance between stress (training and competition load, other life demands) and recovery is essential for athletes to achieve continuous high-level performance. Research has focused on the examination of physiological and psychological recovery strategies to compensate external and internal training and competition loads. A systematic monitoring of recovery and the subsequent implementation of recovery routines aims at maximizing performance and preventing negative developments such as underrecovery, nonfunctional overreaching, the overtraining syndrome, injuries, or illnesses. Due to the inter- and intraindividual variability of responses to training, competition, and recovery strategies, a diverse set of expertise is required to address the multifaceted phenomena of recovery, performance, and their interactions to transfer knowledge from sport science to sport practice. For this purpose, a symposium on Recovery and Performance was organized at the Technical University Munich Science and Study Center Raitenhaslach (Germany) in September 2016. Various international experts from many disciplines and research areas gathered to discuss and share their knowledge of recovery for performance enhancement in a variety of settings. The results of this meeting are outlined in this consensus statement that provides central definitions, theoretical frameworks, and practical implications as a synopsis of the current knowledge of recovery and performance. While our understanding of the complex relationship between recovery and performance has significantly increased through research, some important issues for future investigations are also elaborated.

Kinetic coefficients for the biological treatment of tannery wastewater

International Nuclear Information System (INIS)

Haydar, S.

2008-01-01

Determination of kinetic coefficients for a particular wastewater is imperative for the rational design of biological treatment-facilities. The present study was undertaken with the objective of finding out kinetic coefficients for tannery wastewater. A bench-scale model of aerated lagoon, consisting of an aeration tank and final clarifier, was use to conduct the studies. The model was operated continuously for 96 days, by varying the detention times from 3 to 9 days. Influent for the aerated lagoon was settled tannery wastewater. Biochemical oxygen demand (BOD) of the influent and effluent and the mixed-liquor suspended solids (MLSS) of aeration tank were determined at various detention-times so as to generate data for kinetic coefficients. The kinetic coefficients k, Ks, Y and Ed were found to be 3.125 day/sup -1/, 488 mg/L, 0.64 and 0.035 day/sup -1/ respectively. Overall rate-constant of BOD, removal 'K' was also determined and was found to be 1.43 day/sup -1/. Kinetic coefficients were determined, at mean reactor-temperature of 30.2 degree C. These coefficients may be utilized for the design of biological-treatment facilities for tannery wastewater. (author)

A feasibility study on wavelet transform for reactivity coefficient estimation

International Nuclear Information System (INIS)

Shimazu, Yoichiro

2000-01-01

Recently, a new method using Fourier transform has been introduced in place of the conventional method in order to reduce the time required for the measurement of moderator temperature coefficient in domestic PWRs. The basic concept of these methods is to eliminate noise in the reactivity signal. From this point of view, wavelet analysis is also known as an effective method. In this paper, we tried to apply this method to estimate reactivity coefficients of a nuclear reactor. The basic idea of the reactivity coefficient estimation is to analyze the ratios themselves of the corresponding expansion coefficients of the wavelet transform of the signals of reactivity and the relevant parameter. The concept requires no inverse wavelet transform. Based on numerical simulations, it is found that the method can reasonably estimate reactivity coefficient, for example moderator temperature coefficient, with less length of time sequence data than those required for Fourier transform method. We will continue this study to examine the validity of the estimation procedure for the actual reactor data and further to estimate the other reactivity coefficients. (author)

Transport Coefficients for Holographic Hydrodynamics at Finite Energy Scale

International Nuclear Information System (INIS)

Ge, Xian-Hui; Fang, Li Qing; Yang, Guo-Hong; Leng, Hong-Qiang

2014-01-01

We investigate the relations between black hole thermodynamics and holographic transport coefficients in this paper. The formulae for DC conductivity and diffusion coefficient are verified for electrically single-charged black holes. We examine the correctness of the proposed expressions by taking charged dilatonic and single-charged STU black holes as two concrete examples, and compute the flows of conductivity and diffusion coefficient by solving the linear order perturbation equations. We then check the consistence by evaluating the Brown-York tensor at a finite radial position. Finally, we find that the retarded Green functions for the shear modes can be expressed easily in terms of black hole thermodynamic quantities and transport coefficients

[Recovery: systematic review of a concept].

Science.gov (United States)

Baccari, Ivana Oliveira Preto; Campos, Rosana Teresa Onocko; Stefanello, Sabrina

2015-01-01

The concept of recovery has been described in papers as a state of psychic, physical and social recuperation of day-to-day functions. The scope of this article is to analyze the concepts of the term in different research methodologies and the paradigmatic evolution of the recovery concept. Systematic bibliographical research was conducted in the Pubmed database using the words "recovery + schizophrenia" limited to freely available full papers published in the previous two years. Nineteen papers were analyzed. The majority of the papers sought associations between characteristic data and recovery; few papers discussed the concept in a way to distinguish it from other words like cure or rehabilitation. Recovery as a state in which people with severe mental illness can feel like the creators of their own itinerary tend to be found in qualitative studies and in bibliographic reviews in which the meaning of recovery is not related to the lack of symptoms and tends to prioritize how participative the life of an individual can be despite the disease. Some quantitative studies detect this conceptual difference. In qualitative research there is an increase in the concept of recovery and in ways of promoting it.

Relationship intention and satisfaction following service recovery: The mediating role of perceptions of service recovery in the cell phone industry

Directory of Open Access Journals (Sweden)

L Kruger

2015-11-01

Full Text Available In an industry characterised by fierce competition, cell phone network providers find it increasingly difficult to retain their customers after service failure. It is therefore essential for cell phone network providers to offer effective service recovery when they attempt to restore customer satisfaction following service failure. As it has been argued that relationships between customers and service providers should be considered a key determinant of the service recovery required to restore post-recovery attitudes and behavioural intentions, the purpose of this study was to determine the relationships between South African cell phone customers’ relationship intentions, their perceptions of service recovery and their satisfaction following service recovery. Personal in-home interviews were conducted to collect data from 605 cell phone customers residing in the Johannesburg metropolitan area. In addition to the significant positive relationships found between cell phone users’ relationship intentions, perceived service recovery and satisfaction after service recovery, this study found that perceived service recovery played a mediating role in the relationship between relationship intention and satisfaction following service recovery. The study concludes that, although a direct relationship exists between relationship intention and satisfaction following service recovery, perceived service recovery plays an additional indirect complementary role in this relationship. It is recommended that, in addition to focusing their relationship efforts on customers with relationship intentions, cell phone network providers also offer positively perceived service recovery to these customers, as this would lead to greater satisfaction following service recovery.

Prediction of Partition Coefficients of Organic Compounds for SPME/PDMS

Directory of Open Access Journals (Sweden)

Liao Hsuan-Yu

2016-01-01

Full Text Available The partition coefficients of 51 organic compounds between SPME/PDMS and gas were compiled from the literature sources in this study. The effect of physicochemical properties and descriptors on the partitioning process of partition coefficients was explicated by the correlation analysis. The PDMS-gas partition coefficients were well correlated to the molecular weight of organic compounds (r = 0.832, p < 0.05. An empirical model, consisting of the molecular weight and the polarizability, was developed to appropriately predict the partition coefficients of organic compounds. The empirical model for estimating the PDMS-gas partition coefficient will contribute to the practical applications of the SPME technique.

75 FR 25840 - Endangered and Threatened Species; Recovery Plans; Recovery Plan for the Kemp's Ridley Sea Turtle

Science.gov (United States)

2010-05-10

... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration RIN 0648-XS00 Endangered and Threatened Species; Recovery Plans; Recovery Plan for the Kemp's Ridley Sea Turtle AGENCIES...-National Recovery Plan (Plan) for the Kemp's Ridley Sea Turtle (Lepidochelys kempii). The Kemp's Ridley...

75 FR 12496 - Endangered and Threatened Species; Recovery Plans; Recovery Plan for the Kemp's Ridley Sea Turtle

Science.gov (United States)

2010-03-16

... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration RIN 0648-XS00 Endangered and Threatened Species; Recovery Plans; Recovery Plan for the Kemp's Ridley Sea Turtle AGENCIES... Plan (Plan) for the Kemp's Ridley Sea Turtle (Lepidochelys kempii). The Kemp's Ridley Recovery Plan is...

Comparison of activity coefficient models for electrolyte systems

DEFF Research Database (Denmark)

Lin, Yi; ten Kate, Antoon; Mooijer, Miranda

2010-01-01

Three activity coefficient models for electrolyte solutions were evaluated and compared. The activity coefficient models are: The electrolyte NRTL model (ElecNRTL) by Aspentech, the mixed solvent electrolyte model (MSE) by OLI Systems Inc., and the Extended UNIQUAC model from the Technical Univer...

On the Connection Coefficients of the Chebyshev-Boubaker Polynomials

Directory of Open Access Journals (Sweden)

Paul Barry

2013-01-01

Full Text Available The Chebyshev-Boubaker polynomials are the orthogonal polynomials whose coefficient arrays are defined by ordinary Riordan arrays. Examples include the Chebyshev polynomials of the second kind and the Boubaker polynomials. We study the connection coefficients of this class of orthogonal polynomials, indicating how Riordan array techniques can lead to closed-form expressions for these connection coefficients as well as recurrence relations that define them.

Wavelet Correlation Coefficient of 'strongly correlated' financial time series

OpenAIRE

Razdan, Ashok

2003-01-01

In this paper we use wavelet concepts to show that correlation coefficient between two financial data's is not constant but varies with scale from high correlation value to strongly anti-correlation value This studies is important because correlation coefficient is used to quantify degree of independence between two variables. In econophysics correlation coefficient forms important input to evolve hierarchial tree and minimum spanning tree of financial data.

The effect of follicular fluid hormones on oocyte recovery after ovarian stimulation: FSH level predicts oocyte recovery

Directory of Open Access Journals (Sweden)

Rinaudo Paolo F

2009-04-01

Full Text Available Abstract Background Ovarian stimulation for assisted reproductive technology (ART overcomes the physiologic process to develop a single dominant follicle. However, following stimulation, egg recovery rates are not 100%. The objective of this study is to determine if the follicular fluid hormonal environment is associated with oocyte recovery. Methods This is a prospective study involving patients undergoing ART by standard ovarian stimulation protocols at an urban academic medical center. A total of 143 follicular fluid aspirates were collected from 80 patients. Concentrations of FSH, hCG, estradiol, progesterone, testosterone and prolactin were determined. A multivariable regression analysis was used to investigate the relationship between the follicular fluid hormones and oocyte recovery. Results Intrafollicular FSH was significantly associated with oocyte recovery after adjustment for hCG (Adjusted odds ratio (AOR = 1.21, 95%CI 1.03–1.42. The hCG concentration alone, in the range tested, did not impact the odds of oocyte recovery (AOR = 0.99, 95%CI 0.93–1.07. Estradiol was significantly associated with oocyte recovery (AOR = 0.98, 95% CI 0.96–0.99. After adjustment for progesterone, the strength of association between FSH and oocyte recovery increased (AOR = 1.84, 95%CI 1.45–2.34. Conclusion The relationship between FSH and oocyte recovery is significant and appears to work through mechanisms independent of the sex hormones. FSH may be important for the physiologic event of separation of the cumulus-oocyte complex from the follicle wall, thereby influencing oocyte recovery. Current methods for inducing the final stages of oocyte maturation, with hCG administration alone, may not be optimal. Modifications of treatment protocols utilizing additional FSH may enhance oocyte recovery.

Experimental determination of fission gas adsorption coefficients

International Nuclear Information System (INIS)

Lovell, R.; Underhill, D.W.

1979-01-01

Large charcoal beds have been used for a number of years for the holdup and decay of radioactive isotopes of krypton and xenon. Reliable design of these beds depends on an accurate knowledge of the adsorption coefficient of krypton and xenon on the adsorbents used in these beds. It is somewhat surprising that there is no standard procedure of determining the adsorption coefficient for krypton and xenon. Fundamental information needed to establish a standardized reproducible test procedure is given emphasizing the breakthrough curves commonly used to analyze dynamic adsorption data can lead to serious systematic errors and the fact that the adsorption coefficient, if calculated from the arithmetic holding time, is independent of geometric factors such as the shape of the adsorption bed and the irregular shape of the adsorbent

Disaster Debris Recovery Database - Landfills

Data.gov (United States)

U.S. Environmental Protection Agency — The US EPA Disaster Debris Recovery Database (DDRD) promotes the proper recovery, recycling, and disposal of disaster debris for emergency responders at the federal,...

Coefficients of productivity for Yellowstone's grizzly bear habitat

Science.gov (United States)

Mattson, David John; Barber, Kim; Maw, Ralene; Renkin, Roy

2004-01-01

This report describes methods for calculating coefficients used to depict habitat productivity for grizzly bears in the Yellowstone ecosystem. Calculations based on these coefficients are used in the Yellowstone Grizzly Bear Cumulative Effects Model to map the distribution of habitat productivity and account for the impacts of human facilities. The coefficients of habitat productivity incorporate detailed information that was collected over a 20-year period (1977-96) on the foraging behavior of Yellowstone's bears and include records of what bears were feeding on, when and where they fed, the extent of that feeding activity, and relative measures of the quantity consumed. The coefficients also incorporate information, collected primarily from 1986 to 1992, on the nutrient content of foods that were consumed, their digestibility, characteristic bite sizes, and the energy required to extract and handle each food. Coefficients were calculated for different time periods and different habitat types, specific to different parts of the Yellowstone ecosystem. Stratifications included four seasons of bear activity (spring, estrus, early hyperphagia, late hyperphagia), years when ungulate carrion and whitebark pine seed crops were abundant versus not, areas adjacent to (bear activity in each region, habitat type, and time period were incorporated into calculations, controlling for the effects of proximity to human facilities. The coefficients described in this report and associated estimates of grizzly bear habitat productivity are unique among many efforts to model the conditions of bear habitat because calculations include information on energetics derived from the observed behavior of radio-marked bears.

Effect of Variable Manning Coefficients on Tsunami Inundation

Science.gov (United States)

Barberopoulou, A.; Rees, D.

2017-12-01

Numerical simulations are commonly used to help estimate tsunami hazard, improve evacuation plans, issue or cancel tsunami warnings, inform forecasting and hazard assessments and have therefore become an integral part of hazard mitigation among the tsunami community. Many numerical codes exist for simulating tsunamis, most of which have undergone extensive benchmarking and testing. Tsunami hazard or risk assessments employ these codes following a deterministic or probabilistic approach. Depending on the scope these studies may or may not consider uncertainty in the numerical simulations, the effects of tides, variable friction or estimate financial losses, none of which are necessarily trivial. Distributed manning coefficients, the roughness coefficients used in hydraulic modeling, are commonly used in simulating both riverine and pluvial flood events however, their use in tsunami hazard assessments is primarily part of limited scope studies and for the most part, not a standard practice. For this work, we investigate variations in manning coefficients and their effects on tsunami inundation extent, pattern and financial loss. To assign manning coefficients we use land use maps that come from the New Zealand Land Cover Database (LCDB) and more recent data from the Ministry of the Environment. More than 40 classes covering different types of land use are combined into major classes such as cropland, grassland and wetland representing common types of land use in New Zealand, each of which is assigned a unique manning coefficient. By utilizing different data sources for variable manning coefficients, we examine the impact of data sources and classification methodology on the accuracy of model outputs.

Varying coefficients model with measurement error.

Science.gov (United States)

Li, Liang; Greene, Tom

2008-06-01

We propose a semiparametric partially varying coefficient model to study the relationship between serum creatinine concentration and the glomerular filtration rate (GFR) among kidney donors and patients with chronic kidney disease. A regression model is used to relate serum creatinine to GFR and demographic factors in which coefficient of GFR is expressed as a function of age to allow its effect to be age dependent. GFR measurements obtained from the clearance of a radioactively labeled isotope are assumed to be a surrogate for the true GFR, with the relationship between measured and true GFR expressed using an additive error model. We use locally corrected score equations to estimate parameters and coefficient functions, and propose an expected generalized cross-validation (EGCV) method to select the kernel bandwidth. The performance of the proposed methods, which avoid distributional assumptions on the true GFR and residuals, is investigated by simulation. Accounting for measurement error using the proposed model reduced apparent inconsistencies in the relationship between serum creatinine and GFR among different clinical data sets derived from kidney donor and chronic kidney disease source populations.

76 FR 58781 - Endangered and Threatened Species; Recovery Plans; Recovery Plan for the Kemp's Ridley Sea Turtle

Science.gov (United States)

2011-09-22

... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration RIN 0648-XS00 Endangered and Threatened Species; Recovery Plans; Recovery Plan for the Kemp's Ridley Sea Turtle AGENCY... Sea Turtle (Lepidochelys kempii). The Recovery Plan is a bi-national plan developed by the NMFS and...

Delimiting coefficient alpha from internal consistency and unidimensionality

NARCIS (Netherlands)

Sijtsma, K.

2015-01-01

I discuss the contribution by Davenport, Davison, Liou, & Love (2015) in which they relate reliability represented by coefficient α to formal definitions of internal consistency and unidimensionality, both proposed by Cronbach (1951). I argue that coefficient α is a lower bound to reliability and

Simultaneous interferometric measurement of linear coefficient of thermal expansion and temperature-dependent refractive index coefficient of optical materials.

Science.gov (United States)

Corsetti, James A; Green, William E; Ellis, Jonathan D; Schmidt, Greg R; Moore, Duncan T

2016-10-10

Characterizing the thermal properties of optical materials is necessary for understanding how to design an optical system for changing environmental conditions. A method is presented for simultaneously measuring both the linear coefficient of thermal expansion and the temperature-dependent refractive index coefficient of a sample interferometrically in air. Both the design and fabrication of the interferometer is presented as well as a discussion of the results of measuring both a steel and a CaF2 sample.

Questionnaire on the measurement condition of distribution coefficient

International Nuclear Information System (INIS)

Takebe, Shinichi; Kimura, Hideo; Matsuzuru, Hideo

2001-05-01

The distribution coefficient is used for various transport models to evaluate the migration behavior of radionuclides in the environment and is very important parameter in environmental impact assessment of nuclear facility. The questionnaire was carried out for the purpose of utilizing for the proposal of the standard measuring method of distribution coefficient. This report is summarized the result of questionnairing on the sampling methods and storage condition, the pretreatment methods, the analysis items in the physical/chemical characteristics of the sample, and the distribution coefficient measuring method and the measurement conditions in the research institutes within country. (author)

Apparent Coefficient of Friction of Wheat on Denim.

Science.gov (United States)

Schwab, Charles V

2017-07-31

Calculation of the extraction force for a grain entrapment victim requires a coefficient of friction between the grain and the surface of the victim. Because denim is a common fabric for the work clothes that cover entrapment victims, the coefficient of friction between grain and denim becomes necessary. The purpose of this research was to calculate the apparent coefficient of friction of wheat on denim fabric using a proven procedure. The expectation is to improve the current understanding of conditions that influence extraction forces for victims buried in wheat. The apparent coefficient of friction of wheat on denim fabric was calculated to be 0.167 with a standard deviation of ±0.013. The wheat had a moisture content of 10.7% (w.b.) and bulk density of 778.5 kg m-3. The apparent coefficient of friction of wheat on denim was not significantly affected by pull speeds of 0.004, 0.008, and 0.021 mm s-1 nor normal grain pressures of 3.2, 4.8, 6.3, 7.9, and 11.1 kPa. This is a beginning of understanding the conditions that influence the extraction forces for grain entrapment victims. Copyright© by the American Society of Agricultural Engineers.

The theoretical ultimate magnetoelectric coefficients of magnetoelectric composites by optimization design

International Nuclear Information System (INIS)

Wang, H.-L.; Liu, B.

2014-01-01

This paper investigates what is the largest magnetoelectric (ME) coefficient of ME composites, and how to realize it. From the standpoint of energy conservation, a theoretical analysis is carried out on an imaginary lever structure consisting of a magnetostrictive phase, a piezoelectric phase, and a rigid lever. This structure is a generalization of various composite layouts for optimization on ME effect. The predicted theoretical ultimate ME coefficient plays a similar role as the efficiency of ideal heat engine in thermodynamics, and is used to evaluate the existing typical ME layouts, such as the parallel sandwiched layout and the serial layout. These two typical layouts exhibit ME coefficient much lower than the theoretical largest values, because in the general analysis the stress amplification ratio and the volume ratio can be optimized independently and freely, but in typical layouts they are dependent or fixed. To overcome this shortcoming and achieve the theoretical largest ME coefficient, a new design is presented. In addition, it is found that the most commonly used electric field ME coefficient can be designed to be infinitely large. We doubt the validity of this coefficient as a reasonable ME effect index and consider three more ME coefficients, namely the electric charge ME coefficient, the voltage ME coefficient, and the static electric energy ME coefficient. We note that the theoretical ultimate value of the static electric energy ME coefficient is finite and might be a more proper measure of ME effect

On the Decrease of the Oceanic Drag Coefficient in High Winds

Science.gov (United States)

Donelan, Mark A.

2018-02-01

The sheltering coefficient - prefixing Jeffreys' concept of the exponential wave growth rate at a gas-liquid interface - is shown to be Reynolds number dependent from laboratory measurements of waves and Reynolds stresses. There are two turbulent flow regimes: wind speed range of 2.5 to 30 m/s where the drag coefficients increase with wind speed, and wind speed range of 30 to 50 m/s where sheltering/drag coefficients decrease/saturate with wind speed. By comparing model calculations of drag coefficients - using a fixed sheltering coefficient - with ocean observations over a wind speed range of 1 to 50 m/s a similar Reynolds number dependence of the oceanic sheltering coefficient is revealed. In consequence the drag coefficient is a function of Reynolds number and wave age, and not just wind speed as frequently assumed. The resulting decreasing drag coefficient above 30 m/s is shown to be critical in explaining the rapid intensification so prominent in the climatology of Atlantic hurricanes. The Reynolds number dependence of the sheltering coefficient, when employed in coupled models, should lead to significant improvements in the prediction of intensification and decay of tropical cyclones. A calculation of curvature at the wave crest suggests that at wind speeds above 56.15 m/s all waves-breaking or not-induce steady flow separation leading to a minimum in the drag coefficient. This is further evidence of the veracity of the observations of the oceanic drag coefficient at high winds.

The adsorption coefficient (KOC) of chlorpyrifos in clay soil

International Nuclear Information System (INIS)

Halimah Muhamad; Nashriyah Mat; Tan Yew Ai; Ismail Sahid

2005-01-01

The purpose of this study was to determine the adsorption coefficient (KOC) of chlorpyrifos in clay soil by measuring the Freundlich adsorption coefficient (Kads(f)) and desorption coefficient (1/n value) of chlorpyrifos. It was found that the Freundlich adsorption coefficient (Kads(f)) and the linear regression (r2) of the Freundlich adsorption isotherm for chlorpyrifos in the clay soil were 52.6 L/kg and 0.5244, respectively. Adsorption equilibrium time was achieved within 24 hours for clay soil. This adsorption equilibrium time was used to determine the effect of concentration on adsorption. The adsorption coefficient (KOC) of clay soil was found to be 2783 L/kg with an initial concentration solution of 1 μg/g, soil-solution ratio (1:5) at 300 C when the equilibrium between the soil matrix and solution was 24 hours. The Kdes decreased over four repetitions of the desorption process. The chlorpyrifos residues may be strongly adsorbed onto the surface of clay. (Author)

Studies on absorption coefficient near edge of multi elements

International Nuclear Information System (INIS)

Eisa, M.H.; Shen, H.; Yao, H.Y.; Mi, Y.; Zhou, Z.Y.; Hu, T.D.; Xie, Y.N.

2005-01-01

X-ray absorption near edge structure (XANES) was used to study the near edge mass-absorption coefficients of seven elements, such as, Ti, V, Fe, Co, Ni, Cu and Zn. It is well known that, on the near edge absorption of element, when incident X-ray a few eV change can make the absorption coefficient an order magnitude alteration. So that, there are only a few points mass-absorption coefficient at the near edge absorption and that always average value in published table. Our results showed a wide range of data, the total measured data of mass-absorption coefficient of the seven elements was about 505. The investigation confirmed that XANES is useful technique for multi-element absorption coefficient measurement. Details of experimental methods and results are given and discussed. The experimental work has been performed at Beijing Synchrotron Radiation Facility. The measured values were compared with the published data. Good agreement between experimental results and published data is obtained

Studies on absorption coefficient near edge of multi elements

Science.gov (United States)

Eisa, M. H.; Shen, H.; Yao, H. Y.; Mi, Y.; Zhou, Z. Y.; Hu, T. D.; Xie, Y. N.

2005-12-01

X-ray absorption near edge structure (XANES) was used to study the near edge mass-absorption coefficients of seven elements, such as, Ti, V, Fe, Co, Ni, Cu and Zn. It is well known that, on the near edge absorption of element, when incident X-ray a few eV change can make the absorption coefficient an order magnitude alteration. So that, there are only a few points mass-absorption coefficient at the near edge absorption and that always average value in published table. Our results showed a wide range of data, the total measured data of mass-absorption coefficient of the seven elements was about 505. The investigation confirmed that XANES is useful technique for multi-element absorption coefficient measurement. Details of experimental methods and results are given and discussed. The experimental work has been performed at Beijing Synchrotron Radiation Facility. The measured values were compared with the published data. Good agreement between experimental results and published data is obtained.

Exact coefficients for higher dimensional operators with sixteen supersymmetries

Energy Technology Data Exchange (ETDEWEB)

Chen, Wei-Ming [Department of Physics and Astronomy, National Taiwan University,Taipei 10617, Taiwan, R.O.C. (China); Huang, Yu-tin [Department of Physics and Astronomy, National Taiwan University,Taipei 10617, Taiwan, R.O.C. (China); School of Natural Sciences, Institute for Advanced Study,Princeton, NJ 08540 (United States); Wen, Congkao [INFN Sezione di Roma “Tor Vergata' ,Via della Ricerca Scientifica, 00133 Roma (Italy)

2015-09-15

We consider constraints on higher-dimensional operators for supersymmetric effective field theories. In four dimensions with maximal supersymmetry and SU(4) R-symmetry, we demonstrate that the coefficients of abelian operators F{sup n} with MHV helicity configurations must satisfy a recursion relation, and are completely determined by that of F{sup 4}. As the F{sup 4} coefficient is known to be one-loop exact, this allows us to derive exact coefficients for all such operators. We also argue that the results are consistent with the SL(2,Z) duality symmetry. Breaking SU(4) to Sp(4), in anticipation for the Coulomb branch effective action, we again find an infinite class of operators whose coefficients are determined exactly. We also consider three-dimensional N=8 as well as six-dimensional N=(2,0),(1,0) and (1,1) theories. In all cases, we demonstrate that the coefficient of dimension-six operator must be proportional to the square of that of dimension-four.

The Recovery Knowledge Inventory for Measurement of Nursing Student Views on Recovery-oriented Mental Health Services.

Science.gov (United States)

Happell, Brenda; Byrne, Louise; Platania-Phung, Chris

2015-01-01

Recovery-oriented services are a goal for policy and practice in the Australian mental health service system. Evidence-based reform requires an instrument to measure knowledge of recovery concepts. The Recovery Knowledge Inventory (RKI) was designed for this purpose, however, its suitability and validity for student health professionals has not been evaluated. The purpose of the current article is to report the psychometric features of the RKI for measuring nursing students' views on recovery. The RKI, a self-report measure, consists of four scales: (I) Roles and Responsibilities, (II) Non-Linearity of the Recovery Process, (III) Roles of Self-Definition and Peers, and (IV) Expectations Regarding Recovery. Confirmatory and exploratory factor analyses of the baseline data (n = 167) were applied to assess validity and reliability. Exploratory factor analyses generally replicated the item structure suggested by the three main scales, however more stringent analyses (confirmatory factor analysis) did not provide strong support for convergent validity. A refined RKI with 16 items had internal reliabilities of α = .75 for Roles and Responsibilities, α = .49 for Roles of Self-Definition and Peers, and α = .72, for Recovery as Non-Linear Process. If the RKI is to be applied to nursing student populations, the conceptual underpinning of the instrument needs to be reworked, and new items should be generated to evaluate and improve scale validity and reliability.

Age-dependent dose coefficients for tritium in Asian populations

Energy Technology Data Exchange (ETDEWEB)

Trivedi, A

1999-10-01

The International Commission on Radiological Protection (ICRP) Publications 56 (1989) and 67 (1993) have prescribed the biokinetic models and age-dependent dose coefficients for tritiated water and organically bound tritium. The dose coefficients are computed from values selected to specify the anatomical, morphological and physiological characteristics of a three-month-old, one-year-old, five-year-old, 10-year-old, 15-year-old and adult (Reference Man) Caucasian living in North America and Western Europe. However, values for Reference Man and other age groups are not directly applicable to Asians, because of differences in race, custom, dietary habits and climatic conditions. An Asian Man model, including five age groups, has been proposed by Tanaka and Kawamura (1996, 1998) for use in internal dosimetry. The basic concept of the ICRP Reference Man and the system describing body composition in ICRP Publication 23 (1975) were used. Reference values for Asians were given for the body weight and height, the mass of soft tissue, the mass of body water and the daily fluid balance, and are used to compute the dose coefficients for tritium. The age-dependent dose coefficients for Asians for tritiated water intakes are smaller by 20 to 30% of the currently prescribed values (Trivedi, 1998). The reduction in the dose coefficient values is caused by the increased daily fluid balance among Asians. The dose coefficient for tritiated water is 1.4 x 10{sup -11} Sv Bq{sup -1} for Asian Man compared to 2.0 x 10{sup -11} Sv Bq{sup -1} for Reference Man. The dose coefficients for organically bound tritium are only marginally different from those of the ICRP values. The dose coefficient for organically bound tritium for Asian Man is 4.0 x 10{sup -11} Sv Bq{sup -11} compared to 4.6 x 10{sup -11} Sv Bq{sup -1} for Reference Man. (author)

Age-dependent dose coefficients for tritium in Asian populations

International Nuclear Information System (INIS)

Trivedi, A.

1999-10-01

The International Commission on Radiological Protection (ICRP) Publications 56 (1989) and 67 (1993) have prescribed the biokinetic models and age-dependent dose coefficients for tritiated water and organically bound tritium. The dose coefficients are computed from values selected to specify the anatomical, morphological and physiological characteristics of a three-month-old, one-year-old, five-year-old, 10-year-old, 15-year-old and adult (Reference Man) Caucasian living in North America and Western Europe. However, values for Reference Man and other age groups are not directly applicable to Asians, because of differences in race, custom, dietary habits and climatic conditions. An Asian Man model, including five age groups, has been proposed by Tanaka and Kawamura (1996, 1998) for use in internal dosimetry. The basic concept of the ICRP Reference Man and the system describing body composition in ICRP Publication 23 (1975) were used. Reference values for Asians were given for the body weight and height, the mass of soft tissue, the mass of body water and the daily fluid balance, and are used to compute the dose coefficients for tritium. The age-dependent dose coefficients for Asians for tritiated water intakes are smaller by 20 to 30% of the currently prescribed values (Trivedi, 1998). The reduction in the dose coefficient values is caused by the increased daily fluid balance among Asians. The dose coefficient for tritiated water is 1.4 x 10 -11 Sv Bq -1 for Asian Man compared to 2.0 x 10 -11 Sv Bq -1 for Reference Man. The dose coefficients for organically bound tritium are only marginally different from those of the ICRP values. The dose coefficient for organically bound tritium for Asian Man is 4.0 x 10 -11 Sv Bq -11 compared to 4.6 x 10 -11 Sv Bq -1 for Reference Man. (author)

Calibration factor or calibration coefficient?

International Nuclear Information System (INIS)

Meghzifene, A.; Shortt, K.R.

2002-01-01

Full text: The IAEA/WHO network of SSDLs was set up in order to establish links between SSDL members and the international measurement system. At the end of 2001, there were 73 network members in 63 Member States. The SSDL network members provide calibration services to end-users at the national or regional level. The results of the calibrations are summarized in a document called calibration report or calibration certificate. The IAEA has been using the term calibration certificate and will continue using the same terminology. The most important information in a calibration certificate is a list of calibration factors and their related uncertainties that apply to the calibrated instrument for the well-defined irradiation and ambient conditions. The IAEA has recently decided to change the term calibration factor to calibration coefficient, to be fully in line with ISO [ISO 31-0], which recommends the use of the term coefficient when it links two quantities A and B (equation 1) that have different dimensions. The term factor should only be used for k when it is used to link the terms A and B that have the same dimensions A=k.B. However, in a typical calibration, an ion chamber is calibrated in terms of a physical quantity such as air kerma, dose to water, ambient dose equivalent, etc. If the chamber is calibrated together with its electrometer, then the calibration refers to the physical quantity to be measured per electrometer unit reading. In this case, the terms referred have different dimensions. The adoption by the Agency of the term coefficient to express the results of calibrations is consistent with the 'International vocabulary of basic and general terms in metrology' prepared jointly by the BIPM, IEC, ISO, OIML and other organizations. The BIPM has changed from factor to coefficient. The authors believe that this is more than just a matter of semantics and recommend that the SSDL network members adopt this change in terminology. (author)

Criticality coefficient calculation for a small PWR using Monte Carlo Transport Code

Energy Technology Data Exchange (ETDEWEB)

Trombetta, Debora M.; Su, Jian, E-mail: dtrombetta@nuclear.ufrj.br, E-mail: sujian@nuclear.ufrj.br [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil); Chirayath, Sunil S., E-mail: sunilsc@tamu.edu [Department of Nuclear Engineering and Nuclear Security Science and Policy Institute, Texas A and M University, TX (United States)

2015-07-01

Computational models of reactors are increasingly used to predict nuclear reactor physics parameters responsible for reactivity changes which could lead to accidents and losses. In this work, preliminary results for criticality coefficient calculation using the Monte Carlo transport code MCNPX were presented for a small PWR. The computational modeling developed consists of the core with fuel elements, radial reflectors, and control rods inside a pressure vessel. Three different geometries were simulated, a single fuel pin, a fuel assembly and the core, with the aim to compare the criticality coefficients among themselves.The criticality coefficients calculated were: Doppler Temperature Coefficient, Coolant Temperature Coefficient, Coolant Void Coefficient, Power Coefficient, and Control Rod Worth. The coefficient values calculated by the MCNP code were compared with literature results, showing good agreement with reference data, which validate the computational model developed and allow it to be used to perform more complex studies. Criticality Coefficient values for the three simulations done had little discrepancy for almost all coefficients investigated, the only exception was the Power Coefficient. Preliminary results presented show that simple modelling as a fuel assembly can describe changes at almost all the criticality coefficients, avoiding the need of a complex core simulation. (author)

Mortality, recovery, and community shifts of scleractinian corals in Puerto Rico one decade after the 2005 regional bleaching event

Directory of Open Access Journals (Sweden)

Jorge R. García-Sais

2017-07-01

Full Text Available This work analyzes the mortality, recovery, and shifts in the composition of scleractinian corals from Puerto Rico one decade after the 2005 regional coral bleaching event. Temporal and spatial patterns of coral community structure were examined using a stratified, non-random sampling approach based on five permanent transects per reef at 16 reef stations. A negative correlation between percent coral cover loss and light attenuation coefficient (Kd490 was observed, suggesting that light attenuation, as influenced by water turbidity and depth, played a major role in coral protection during the bleaching event (“sunblock effect”. Responses of coral assemblages varied after the bleaching event, including shifts of cover from massive corals (Orbicella spp. to opportunistic (Porites astreoides and branching corals (Madracis auretenra, P. porites and/or turf algae; partial recovery of reef substrate cover by O. annularis complex; and no measurable changes in coral assemblages before and after the event.

Seeley-Gilkey coefficients for fourth-order operators on Riemannian manifold

International Nuclear Information System (INIS)

Gusynin, V.P.

1990-01-01

The covariant pseudodifferential-operator method of Widom is developed for computing the coefficients in the heat kernel expansion. It allows one to calculate Seeley-Gilkey coefficients for both minimal and nonminimal differential operators acting on a vector bundle over a riemannian manifold. The coefficients for the fourth-order minimal operators in arbitrary dimensions of space are calculated. In contrast to the second-order operators the coefficients for the fourth-order (and higher) operators turn out to be essentially dependent on the space dimension. The algorithmic character of the method allows one to calculate the coefficients by computer using an analytical calculation system. The method also permits a simple generalization to manifolds with torsion and supermanifolds. (orig.)

Contested understandings of recovery in mental health.

Science.gov (United States)

McCabe, Rhiannah; Whittington, Richard; Cramond, Laura; Perkins, Elizabeth

2018-05-17

The concept of recovery is contested throughout the existing literature and in mental health services. Little research exists that gives voice to service user perspectives of recovery. This paper explores how service users in two recovery oriented services run by the National Health Service in North West England talked about recovery and what it meant to them. 14 service users accessing these services took part in semi-structured qualitative interviews focusing on the concept of recovery. Data were analysed using an interpretive phenomenological analysis approach. Service users talked about recovery as a dynamic, day to day process as well as an outcome; specifically related to being discharged from inpatient settings. A number of factors including relationships and medication were cited to have the potential to make or break recovery. The study highlights the continued dominance of the biomedical model in mental health services. Service users appear to have internalised staff and services' understanding of recovery perhaps unsurprisingly given the power differential in these relationships. Implications for clinical practice are explored.

Isothermal recovery rates in shape memory polyurethanes

International Nuclear Information System (INIS)

Azra, Charly; Plummer, Christopher J G; Månson, Jan-Anders E

2011-01-01

This work compares the time dependence of isothermal shape recovery in thermoset and thermoplastic shape memory polyurethanes (SMPUs) with comparable glass transition temperatures. In each case, tensile tests have been used to quantify the influence of various thermo-mechanical programming parameters (deformation temperature, recovery temperature, and stress and storage times following the deformation step) on strain recovery under zero load (free recovery) and stress recovery under fixed strain (constrained recovery). It is shown that the duration of the recovery event may be tuned over several decades of time with an appropriate choice of programming parameters, but that there is a trade-off between the rate of shape recovery and the recoverable stress level. The results are discussed in terms of the thermal characteristics of the SMPUs in the corresponding temperature range as characterized by modulated differential scanning calorimetry and dynamic mechanical analysis, with the emphasis on the role of the effective width of the glass transition temperature and the stability of the network that gives rise to the shape memory effect. (fast track communication)

Uncertainties in Cancer Risk Coefficients for Environmental Exposure to Radionuclides. An Uncertainty Analysis for Risk Coefficients Reported in Federal Guidance Report No. 13

Energy Technology Data Exchange (ETDEWEB)

Pawel, David [U.S. Environmental Protection Agency; Leggett, Richard Wayne [ORNL; Eckerman, Keith F [ORNL; Nelson, Christopher [U.S. Environmental Protection Agency

2007-01-01

Federal Guidance Report No. 13 (FGR 13) provides risk coefficients for estimation of the risk of cancer due to low-level exposure to each of more than 800 radionuclides. Uncertainties in risk coefficients were quantified in FGR 13 for 33 cases (exposure to each of 11 radionuclides by each of three exposure pathways) on the basis of sensitivity analyses in which various combinations of plausible biokinetic, dosimetric, and radiation risk models were used to generate alternative risk coefficients. The present report updates the uncertainty analysis in FGR 13 for the cases of inhalation and ingestion of radionuclides and expands the analysis to all radionuclides addressed in that report. The analysis indicates that most risk coefficients for inhalation or ingestion of radionuclides are determined within a factor of 5 or less by current information. That is, application of alternate plausible biokinetic and dosimetric models and radiation risk models (based on the linear, no-threshold hypothesis with an adjustment for the dose and dose rate effectiveness factor) is unlikely to change these coefficients by more than a factor of 5. In this analysis the assessed uncertainty in the radiation risk model was found to be the main determinant of the uncertainty category for most risk coefficients, but conclusions concerning the relative contributions of risk and dose models to the total uncertainty in a risk coefficient may depend strongly on the method of assessing uncertainties in the risk model.

Total Value of Phosphorus Recovery.

Science.gov (United States)

Mayer, Brooke K; Baker, Lawrence A; Boyer, Treavor H; Drechsel, Pay; Gifford, Mac; Hanjra, Munir A; Parameswaran, Prathap; Stoltzfus, Jared; Westerhoff, Paul; Rittmann, Bruce E

2016-07-05

Phosphorus (P) is a critical, geographically concentrated, nonrenewable resource necessary to support global food production. In excess (e.g., due to runoff or wastewater discharges), P is also a primary cause of eutrophication. To reconcile the simultaneous shortage and overabundance of P, lost P flows must be recovered and reused, alongside improvements in P-use efficiency. While this motivation is increasingly being recognized, little P recovery is practiced today, as recovered P generally cannot compete with the relatively low cost of mined P. Therefore, P is often captured to prevent its release into the environment without beneficial recovery and reuse. However, additional incentives for P recovery emerge when accounting for the total value of P recovery. This article provides a comprehensive overview of the range of benefits of recovering P from waste streams, i.e., the total value of recovering P. This approach accounts for P products, as well as other assets that are associated with P and can be recovered in parallel, such as energy, nitrogen, metals and minerals, and water. Additionally, P recovery provides valuable services to society and the environment by protecting and improving environmental quality, enhancing efficiency of waste treatment facilities, and improving food security and social equity. The needs to make P recovery a reality are also discussed, including business models, bottlenecks, and policy and education strategies.

Global patterns of drought recovery

Energy Technology Data Exchange (ETDEWEB)

Schwalm, Christopher R.; Anderegg, William R. L.; Michalak, Anna M.; Fisher, Joshua B.; Biondi, Franco; Koch, George; Litvak, Marcy; Ogle, Kiona; Shaw, John D.; Wolf, Adam; Huntzinger, Deborah N.; Schaefer, Kevin; Cook, Robert; Wei, Yaxing; Fang, Yuanyuan; Hayes, Daniel; Huang, Maoyi; Jain, Atul; Tian, Hanqin

2017-08-09

Drought is a recurring multi-factor phenomenon with major impacts on natural and human systems1-3. Drought is especially important for land carbon sink variability, influencing climate regulation of the terrestrial biosphere4. While 20th Century trends in drought regime are ambiguous, “more extreme extremes” as well as more frequent and severe droughts3,7 are expected in the 21st Century. Recovery time, the length of time an ecosystem requires to revert to its pre-drought functional state, is a critical metric of drought impact. Yet the spatiotemporal patterning and controls of drought recovery are largely unknown. Here we use three distinct global datasets of gross primary productivity to show that across diverse terrestrial ecosystems drought recovery times are driven by biological productivity and biodiversity, with drought length and severity of secondary importance. Recovery time, especially for extreme droughts, and the areal extent of ecosystems in recovery from drought generally increase over the 20th Century, supporting an increase globally in drought impact8. Our results indicate that if future Anthropocene droughts become more widespread as expected, that droughts will become more frequent relative to recovery time. This increases the risk of entering a new regime where vegetation never recovers to its original state and widespread degradation of the land carbon sink ensues.

Stochastic Modelling of the Diffusion Coefficient for Concrete

DEFF Research Database (Denmark)

Thoft-Christensen, Palle

In the paper, a new stochastic modelling of the diffusion coefficient D is presented. The modelling is based on physical understanding of the diffusion process and on some recent experimental results. The diffusion coefficients D is strongly dependent on the w/c ratio and the temperature....

Recovery of heart rate variability after treadmill exercise analyzed by lagged Poincaré plot and spectral characteristics.

Science.gov (United States)

Shi, Ping; Hu, Sijung; Yu, Hongliu

2018-02-01

The aim of this study was to analyze the recovery of heart rate variability (HRV) after treadmill exercise and to investigate the autonomic nervous system response after exercise. Frequency domain indices, i.e., LF(ms 2 ), HF(ms 2 ), LF(n.u.), HF(n.u.) and LF/HF, and lagged Poincaré plot width (SD1 m ) and length (SD2 m ) were introduced for comparison between the baseline period (Pre-E) before treadmill running and two periods after treadmill running (Post-E1 and Post-E2). The correlations between lagged Poincaré plot indices and frequency domain indices were applied to reveal the long-range correlation between linear and nonlinear indices during the recovery of HRV. The results suggested entirely attenuated autonomic nervous activity to the heart following the treadmill exercise. After the treadmill running, the sympathetic nerves achieved dominance and the parasympathetic activity was suppressed, which lasted for more than 4 min. The correlation coefficients between lagged Poincaré plot indices and spectral power indices could separate not only Pre-E and two sessions after the treadmill running, but also the two sessions in recovery periods, i.e., Post-E1 and Post-E2. Lagged Poincaré plot as an innovative nonlinear method showed a better performance over linear frequency domain analysis and conventional nonlinear Poincaré plot.

Music and psychophysiological recovery from stress.

Science.gov (United States)

Radstaak, Mirjam; Geurts, Sabine A E; Brosschot, Jos F; Kompier, Michiel A J

2014-09-01

This experimental study examined whether listening to self-chosen music after stress exposure improves mood, decreases subjective arousal and rumination, and facilitates cardiovascular recovery. Participants (N = 123) were exposed to a mental arithmetic task with harassment to induce stress. Afterward, participants were randomly assigned to one of four "recovery" conditions where they (1) listened to self-chosen relaxing music, (2) listened to self-chosen happy music, (3) listened to an audio book, or (4) sat in silence. After this 5-minute "recovery manipulation period," participants sat in silence for another 5 minutes. Systolic blood pressure, diastolic blood pressure, and heart rate were continuously measured. The recovery conditions caused differences in positive affect (F(3,119) = 13.13, p music or happy music. The conditions showed no differences in subjective arousal (F(3,117) = 2.03, p = .11) and rumination (F(3,119) = 1.10, p = .35). Systolic blood pressure recovery, however, differed between the conditions (linear time trend: F(3,116) = 4.50, p = .005; quadratic time trend: F(3,115) = 5.24, p = .002). Listening to both relaxing and happy music delayed systolic blood pressure recovery when compared with both control conditions. Listening to self-selected music is an effective mood enhancer, but it delays blood pressure recovery.

Launch and Recovery System Literature Review

Science.gov (United States)

2010-12-01

water. Goldie [21] suggests a sled or cart recovery system for use with UAV’s on the Littoral Combatant Ship (LCS) and other small deck navy ships...21. Goldie , J., “A Recovery System for Unmanned Aerial Vehicles (UAVs) Aboard LCS and other Small-Deck Navy Ships,” ASNE Launch and Recovery of

Coping and recovery in whiplash-associated disorders

DEFF Research Database (Denmark)

Carroll, Linda J; Ferrari, Robert; Cassidy, John David

2014-01-01

Management Inventory, and neck pain recovery was assessed at each subsequent follow-up, using a 100 mm visual analogue scale (VAS). Disability was assessed at each follow-up using the Pain Disability Index (PDI). Pain recovery was defined as a VAS score of 0 to 10; disability recovery was defined as a PDI...... recovery, reductions in neck pain, and in disability. METHODS: A population-based prospective cohort study design was used to study 2986 adults with traffic-related WAD. Participants were assessed at baseline, 6 weeks, and 4, 8, and 12 months postinjury. Coping was measured at 6 weeks using the Pain...... score of 0 to 4. Data analysis used multivariable Cox proportional hazards models. RESULTS: Those using high versus low levels of passive coping at 6 weeks postinjury experienced 28% slower pain recovery and 43% slower disability recovery. Adjusted hazard rate ratios for pain recovery and disability...

Object detection by correlation coefficients using azimuthally averaged reference projections.

Science.gov (United States)

Nicholson, William V

2004-11-01

A method of computing correlation coefficients for object detection that takes advantage of using azimuthally averaged reference projections is described and compared with two alternative methods-computing a cross-correlation function or a local correlation coefficient versus the azimuthally averaged reference projections. Two examples of an application from structural biology involving the detection of projection views of biological macromolecules in electron micrographs are discussed. It is found that a novel approach to computing a local correlation coefficient versus azimuthally averaged reference projections, using a rotational correlation coefficient, outperforms using a cross-correlation function and a local correlation coefficient in object detection from simulated images with a range of levels of simulated additive noise. The three approaches perform similarly in detecting macromolecular views in electron microscope images of a globular macrolecular complex (the ribosome). The rotational correlation coefficient outperforms the other methods in detection of keyhole limpet hemocyanin macromolecular views in electron micrographs.

All-Coefficient Adaptive Control of Dual-Motor Driving Servo System

Directory of Open Access Journals (Sweden)

Zhao Haibo

2017-01-01

Full Text Available Backlash nonlinearity and friction nonlinearity exist in dual-motor driving servo system, which reducing system response speed, steady accuracy and anti-interference ability. In order to diminish the adverse effects of backlash and friction nonlinearity to system, we proposed a new all-coefficient adaptive control method. Firstly, we introduced the dynamic model of backlash and friction nonlinearity respectively. Then on this basis, we established the characteristic model when backlash and friction nonlinearity coexist. We used recursive least square method for parameter estimation. Finally we designed the all-coefficient adaptive controller. On the basis of simplex all-coefficient adaptive controller, we designed a feedforward all-coefficient adaptive controller. The simulations of feedforward all-coefficient adaptive control and simplex all-coefficient adaptive control were compared. The results show that the former has quicker response speed, higher steady accuracy, stronger anti-interference performance and better robustness, which validating the efficacy of the proposed control strategy.

Coefficient of restitution of model repaired car body parts

OpenAIRE

D. Hadryś; M. Miros

2008-01-01

Purpose: The qualification of influence of model repaired car body parts on the value of coefficient of restitution and evaluation of impact energy absorption of model repaired car body parts.Design/methodology/approach: Investigation of plastic strain and coefficient of restitution of new and repaired model car body parts with using impact test machine for different impact energy.Findings: The results of investigations show that the value of coefficient of restitution changes with speed (ene...

Purification, crystallization and preliminary X-ray diffraction of fluorescence recovery protein from Synechocystis PCC 6803

International Nuclear Information System (INIS)

Liu, Ting; Shuai, Yingli; Zhou, Honggang

2011-01-01

Fluorescence recovery protein from Synechocystis PCC 6803 plays a key role in the orange carotenoid protein-related photoprotective mechanism in cyanobacteria. The full-length form and a truncated form were overexpressed, purified and crystallized, and diffraction was observed to 2.75 Å resolution. Fluorescence recovery protein (FRP), which is encoded by the slr1964 gene in Synechocystis PCC 6803, plays a key role in the orange carotenoid protein-related photoprotective mechanism in cyanobacteria. As the crystal structure of FRP may provide information about the biological functions and mechanism of action of the protein, recombinant full-length FRP and a truncated form were overexpressed, purified and crystallized at 291 K using ethylene imine polymer as the precipitant. An FRP data set was collected to a resolution of 2.75 Å at low temperature (100 K). The crystal belonged to space group P4 1 2 1 2, with unit-cell parameters a = b = 61.9, c = 160.7 Å, α = β = γ = 90°. Assuming that the asymmetric unit contains three molecules, the Matthews coefficient was calculated to be 2.1 Å 3 Da −1

Recovery i fællesskaber

DEFF Research Database (Denmark)

Nielsen, Diana Astrup

2013-01-01

in present day practice. The dissertation aims at examining the potentials and limitations of recovery-orientation in a context of practice, and is thus concerned with the question: Which limitations and potentials emerge for recovery-orientation, when the applications of the the-ory are investigated...... gathered consists of interviews with the residents and recordings from institutional staff meetings at the establishment. The analyses presented in the dissertation are from in-depth studies of two select cases with resi-dents of the establishment. Two theoretical approaches are applied to each case...... as for identifying suggestions for improving and developing such practice. 4 The analyses of the empirical data presented serve to identify limitations, as well as potentials for practice based upon recovery-orientation. The approach from critical psychology supports that the concepts of recovery-orientation lack...

Transport coefficients for dense hard-disk systems.

Science.gov (United States)

García-Rojo, Ramón; Luding, Stefan; Brey, J Javier

2006-12-01

A study of the transport coefficients of a system of elastic hard disks based on the use of Helfand-Einstein expressions is reported. The self-diffusion, the viscosity, and the heat conductivity are examined with averaging techniques especially appropriate for event-driven molecular dynamics algorithms with periodic boundary conditions. The density and size dependence of the results are analyzed, and comparison with the predictions from Enskog's theory is carried out. In particular, the behavior of the transport coefficients in the vicinity of the fluid-solid transition is investigated and a striking power law divergence of the viscosity with density is obtained in this region, while all other examined transport coefficients show a drop in that density range in relation to the Enskog's prediction. Finally, the deviations are related to shear band instabilities and the concept of dilatancy.

Changes in transcription during recovery from heat injury in Salmonella typhimurium and effects of BCAA on recovery.

Science.gov (United States)

Hsu-Ming, Wen; Naito, Kimitaka; Kinoshita, Yoshimasa; Kobayashi, Hiroshi; Honjoh, Ken-ichi; Tashiro, Kousuke; Miyamoto, Takahisa

2012-06-01

Mechanisms of recovery from heat injury in Salmonella typhimurium were elucidated. Recovery of the heat-injured S. typhimurium cells in TSB resulted in full recovery after 3 h of incubation at 37°C. The DNA microarray analysis of 30- and 60-min recovering cells resulted in an increase in transcription of 89 and 141 genes, respectively. Among them, 15 genes, with known function, seemed to be somewhat involved in recovery. They encoded proteins involved in branched-chain amino acid (BCAA) transport (livJ, livH), cell envelope integrity (ddg), heat-shock response (cpxP, rrmJ), phage shock protein (pspA), ribosome modulation factor (rmf), virulence (sseB) transcriptional regulation (rpoE, rpoH, rseA, rseB, rseC) and ArcB signal transduction (sixA) and cytoplasmic membrane protein (fxsA). Among them, the effects of BCAA supplementation on recovery from heat injury were studied to confirm the importance of the BCAA transport liv genes during recovery. It was found that supplementation of TSB with 0.1% BCAA resulted in an enhanced recovery of injured cells in comparison to those recovered in TSB without BCAA. Supplementation of BCAA at 0.1% resulted in a cell count increase 4.4-fold greater than that of the control after 1 h incubation. It seems that BCAA promoted the recovery by promoting protein synthesis either directly through their use in translation or indirectly through stimulation of protein synthesis by activation of the Lrp protein.

Modeling a Thermoelectric Generator Applied to Diesel Automotive Heat Recovery

Science.gov (United States)

Espinosa, N.; Lazard, M.; Aixala, L.; Scherrer, H.

2010-09-01

Thermoelectric generators (TEGs) are outstanding devices for automotive waste heat recovery. Their packaging, lack of moving parts, and direct heat to electrical conversion are the main benefits. Usually, TEGs are modeled with a constant hot-source temperature. However, energy in exhaust gases is limited, thus leading to a temperature decrease as heat is recovered. Therefore thermoelectric properties change along the TEG, affecting performance. A thermoelectric generator composed of Mg2Si/Zn4Sb3 for high temperatures followed by Bi2Te3 for low temperatures has been modeled using engineering equation solver (EES) software. The model uses the finite-difference method with a strip-fins convective heat transfer coefficient. It has been validated on a commercial module with well-known properties. The thermoelectric connection and the number of thermoelements have been addressed as well as the optimum proportion of high-temperature material for a given thermoelectric heat exchanger. TEG output power has been estimated for a typical commercial vehicle at 90°C coolant temperature.

Stress and Recovery during Simulated Microgravity

Science.gov (United States)

Nicolas, Michel

The aim of this study was to determine the effects of a 60-day head-down tilt long-term bed rest (HDT) on stress and recovery in sixteen healthy female volunteers during the WISE-2005 study (Women International Space Simulation for Exploration). Participants were randomly assigned to either an exercise group (Exe) that followed a training program combining resistive and aerobic exercises, or to a no-exercise control group (Ctl). Psychological states were assessed using the Rest-Q, a validated questionnaire based on stress-recovery responses. A longitudinal analysis revealed significant changes in the general and specific stress scales for all participants throughout the experiment with a critical stage from supine to standing posture leading to a significant decrease in physical recovery. During HDT, Exe reported higher scores in stress subscales, as well as lower recovery scores compared to the Ctl. During the post HDT ambulatory recovery period, the exercisers still reported higher scores than the non-exercisers on the Lack of energy stress related scale, along with lower scores in general well-being and personal accomplishment. The present findings show that simulated weightlessness such as HDT may induce psychological stress and lead to subsequent alterations in perceived recovery. Exercise did not reduce HDT impaired effects on stress and recovery states. In the perspective of spaceflights of long-duration such as the future missions to Mars, there is a need for additional experiments to further investigate spaceflight-induced changes of stress and recovery parameters and the effects of exercise on these parameters. Further studies might determine and analyze the psychological factors involved, but also how to intervene concerning these factors with efficient psychological preparation which, although not yet fully investigated, may reduce stress, promote recovery and support adaptive responses to such extreme environments.

Microfluidic diffusivity meter: a tool to optimize CO2 driven enhanced oil recovery

Science.gov (United States)

Puneeth, S. B.; Kim, Young Ho; Goel, Sanket

2017-02-01

As the energy demands continue to swell with growing population and there persists a lack of unexploited oilfields, the prime focus of any nation would be to maximize the oil recovery factor from existing oil fields. CO2-Enhanced oil recovery is a process to improve the recovery of crude oil from an oil field and works at high pressure and in very deep conditions. CO2 and oil are miscible at high pressure, resulting in low viscosity and oil swells. This swelling can be measured based on mathematical calculations in real time and correlated with the CO2 concentration. This process has myriad advantages over its counterparts which include being able to harness oil trapped in reservoirs besides being cheaper and more efficient. A Diffusivity meter is inevitable in the measurement of the diffusion co-efficient of two samples. Diffusivity meters currently available in the market are weighed down by disadvantages like the requirement of large samples for testing, high cost and complexity. This elicits the need for a Microfluidic based diffusivity meter capable of analyzing Nano-liter sample volumes besides being more precise and affordable. The scope of this work involves the design and development of a Microfluidic robust and inexpensive prototype diffusivity meter using a capillary tube and endorsing its performance by comparison of results with known diffusivity range and supervision of the results with an electronic microscope coupled to PC and Data Acquisition System. The prototype produced at the end of the work is expected to outweigh disadvantages in existing products in terms of sample size, efficiency and time saving.

On the Occurrence of Standardized Regression Coefficients Greater than One.

Science.gov (United States)

Deegan, John, Jr.

1978-01-01

It is demonstrated here that standardized regression coefficients greater than one can legitimately occur. Furthermore, the relationship between the occurrence of such coefficients and the extent of multicollinearity present among the set of predictor variables in an equation is examined. Comments on the interpretation of these coefficients are…

Simulating WTP Values from Random-Coefficient Models

OpenAIRE

Maurus Rischatsch

2009-01-01

Discrete Choice Experiments (DCEs) designed to estimate willingness-to-pay (WTP) values are very popular in health economics. With increased computation power and advanced simulation techniques, random-coefficient models have gained an increasing importance in applied work as they allow for taste heterogeneity. This paper discusses the parametrical derivation of WTP values from estimated random-coefficient models and shows how these values can be simulated in cases where they do not have a kn...

Investigation of photon attenuation coefficients for marble

International Nuclear Information System (INIS)

Basyigit, C; Akkurt, I; Kilincarslan, S; Akkurt, A

2005-01-01

The total linear attenuation coefficients μ (cm -1 ) have been obtained using the XCOM program at photon energies of 1 keV to 1 GeV for six different natural marbles produced in different places in Turkey. The individual contribution of photon interaction processes to the total linear attenuation coefficients for marble has been investigated. The calculated results were also compared with the measurements. The results obtained for marble were also compared with concrete. (note)

Thermal recovery gaining importance, says expert

Energy Technology Data Exchange (ETDEWEB)

1964-12-21

In a forecast presented to the Calgary section CIM- AIME at a recent monthly technical meeting, J.V. Howard, Core Labs. Inc., predicted that within the next 2 to 5 yr, California oil production will come from thermal recovery schemes to the extent of 200,000 bpd. One American major oil company is planning a fire flood in a heavy oil reservoir at 12,000 ft depth, where primary recovery is estimated as only 3% of original oil in place. It is estimated that the minimum oil saturation feasible for thermal recovery is 950 bbl per acre-ft. The larger number of variables that will determine the success or failure of thermal recovery makes it essential to have thorough and complete studies of all the thermal processes before one is selected for a given set of reservoir and economic conditions. The number of thermal recovery projects will increase rapidly and the success of any project will depend upon the proper application of experience and technology in thermal recovery.

Recovery and permanent radiation damage of plastic scintillators at different dose rates

International Nuclear Information System (INIS)

Bicken, B.; Holm, U.; Marckmann, T.; Wick, K.; Rhode, M.

1990-01-01

This paper reports on the radiation stability of plastic scintillators and wavelength shifters for the calorimeter of the ZEUS detector by irradiating them with protons, a 60 Co-source, and depleted uranium. Changes in light yield, absorption length and absorption coefficient have been measured for storage in inert and oxygen atmospheres during and after irradiation. Radiation doses up to 40 kGy with dose rates of 30 up to 2000 Gy/h have been applied. The polystyrene based scintillator SCSN-38 and the wavelength shifters Y-7 and K-27 in PMMA show an additional absorption but a recovery in air to a low permanent damage (at 10 kGy) which is proportional to the applied dose. Series investigations on samples of all production cycles of the ZEUS scintillators with high dose rates show only minor differences in radiation hardness. The recovery is described by a simple oxygen diffusion model for high and medium dose rates down to 30 Gy/h. During long term irradiations at low dose rates (<100 Gy/h) of 3 mm thick SCSN-38 in air the radiation damage recovers to a permanent damage which does not depend on the dose rate. On the other hand the radiation damage at very low dose rates (17 Gy/a) seems to be higher than expected for the accumulated dose

Conservation genetics in the recovery of endangered animal species: a review of US endangered species recovery plans (1977-1998

Directory of Open Access Journals (Sweden)

Moyle, L. C.

2003-12-01

Full Text Available The utility of genetic data in conservation efforts, particularly in comparison to demographic information, is the subject of ongoing debate. Using a database of information surveyed from 181 US endangered and threatened species recovery plans, we addressed the following questions concerning the use of genetic information in animal recovery plans: I. What is the relative prominence of genetic vs. demographic data in recovery plan development? and, II. When are genetic factors viewed as a threat, and how do plans respond to genetic threats? In general, genetics appear to play a minor and relatively ill-defined part in the recovery planning process; demographic data are both more abundant and more requested in recovery plans, and tasks are more frequently assigned to the collection / monitoring of demographic rather than genetic information. Nonetheless, genetic threats to species persistence and recovery are identified in a substantial minority (22% of recovery plans, although there is little uniform response to these perceived threats in the form of specific proposed recovery or management tasks. Results indicate that better guidelines are needed to identify how and when genetic information is most useful for species recovery; we highlight specific contexts in which genetics may provide unique management information, beyond that provided by other kinds of data.

Long recovery VLF perturbations associated with lightning discharges

Science.gov (United States)

Salut, M. M.; Abdullah, M.; Graf, K. L.; Cohen, M. B.; Cotts, B. R. T.; Kumar, Sushil

2012-08-01

Long D-region ionospheric recovery perturbations are a recently discovered and poorly understood subcategory of early VLF events, distinguished by exceptionally long ionospheric recovery times of up to 20 min (compared to more typical ˜1 min recovery times). Characteristics and occurrence rates of long ionospheric recovery events on the NWC transmitter signal recorded at Malaysia are presented. 48 long recovery events were observed. The location of the causative lightning discharge for each event is determined from GLD360 and WWLLN data, and each discharge is categorized as being over land or sea. Results provide strong evidence that long recovery events are attributed predominately to lightning discharges occurring over the sea, despite the fact that lightning activity in the region is more prevalent over land. Of the 48 long recovery events, 42 were attributed to lightning activity over water. Analysis of the causative lightning of long recovery events in comparison to all early VLF events reveals that these long recovery events are detectable for lighting discharges at larger distances from the signal path, indicating a different scattering pattern for long recovery events.

Delimiting Coefficient a from Internal Consistency and Unidimensionality

Science.gov (United States)

Sijtsma, Klaas

2015-01-01

I discuss the contribution by Davenport, Davison, Liou, & Love (2015) in which they relate reliability represented by coefficient a to formal definitions of internal consistency and unidimensionality, both proposed by Cronbach (1951). I argue that coefficient a is a lower bound to reliability and that concepts of internal consistency and…

Research on the Fault Coefficient in Complex Electrical Engineering

Directory of Open Access Journals (Sweden)

Yi Sun

2015-08-01

Full Text Available Fault detection and isolation in a complex system are research hotspots and frontier problems in the reliability engineering field. Fault identification can be regarded as a procedure of excavating key characteristics from massive failure data, then classifying and identifying fault samples. In this paper, based on the fundamental of feature extraction about the fault coefficient, we will discuss the fault coefficient feature in complex electrical engineering in detail. For general fault types in a complex power system, even if there is a strong white Gaussian stochastic interference, the fault coefficient feature is still accurate and reliable. The results about comparative analysis of noise influence will also demonstrate the strong anti-interference ability and great redundancy of the fault coefficient feature in complex electrical engineering.

Determination of ion diffusion coefficients by the electromigration method

International Nuclear Information System (INIS)

Bonchev, G.D.; Milanov, M.V.; Bozhikov, G.A.; Ivanov, P.I.; Priemyshev, A.N.; Maslov, O.D.; Dmitriev, S.N.

2003-01-01

An electrophoretic method for measuring ion diffusion coefficients in aqueous solutions is developed. The value of the diffusion coefficient can be determined from the linear relationship between the square standard deviation of the electrophoretic zone and the time from the start of the diffusion process. Using the device for horizontal zone electrophoresis in a free electrolyte, a series of diffusion experiments are performed with no-carrier-added radionuclides in microconcentrations (10 -9 - 10 -10 M). Diffusion coefficients of 111 In(III), 175 Hf(IV) and 237 Pu(VI) ions at 25 0 C are determined in nitric acid media. Simultaneous determination of the diffusion coefficient and electrophoretic mobility allows one to calculate the effective charge of the investigated ions in accordance with the Nernst-Einstein law

Nutrition for recovery in aquatic sports.

Science.gov (United States)

Burke, Louise M; Mujika, Iñigo

2014-08-01

Postexercise recovery is an important topic among aquatic athletes and involves interest in the quality, quantity, and timing of intake of food and fluids after workouts or competitive events to optimize processes such as refueling, rehydration, repair, and adaptation. Recovery processes that help to minimize the risk of illness and injury are also important but are less well documented. Recovery between workouts or competitive events may have two separate goals: (a) restoration of body losses and changes caused by the first session to restore performance for the next and (b) maximization of the adaptive responses to the stress provided by the session to gradually make the body become better at the features of exercise that are important for performance. In some cases, effective recovery occurs only when nutrients are supplied, and an early supply of nutrients may also be valuable in situations in which the period immediately after exercise provides an enhanced stimulus for recovery. This review summarizes contemporary knowledge of nutritional strategies to promote glycogen resynthesis, restoration of fluid balance, and protein synthesis after different types of exercise stimuli. It notes that some scenarios benefit from a proactive approach to recovery eating, whereas others may not need such attention. In fact, in some situations it may actually be beneficial to withhold nutritional support immediately after exercise. Each athlete should use a cost-benefit analysis of the approaches to recovery after different types of workouts or competitive events and then periodize different recovery strategies into their training or competition programs.

An Investigation of the Sampling Distribution of the Congruence Coefficient.

Science.gov (United States)

Broadbooks, Wendy J.; Elmore, Patricia B.

This study developed and investigated an empirical sampling distribution of the congruence coefficient. The effects of sample size, number of variables, and population value of the congruence coefficient on the sampling distribution of the congruence coefficient were examined. Sample data were generated on the basis of the common factor model and…

Characterization of the effective electrostriction coefficients in ferroelectric thin films

Science.gov (United States)

Kholkin, A. L.; Akdogan, E. K.; Safari, A.; Chauvy, P.-F.; Setter, N.

2001-06-01

Electromechanical properties of a number of ferroelectric films including PbZrxTi1-xO3(PZT), 0.9PbMg1/3Nb2/3O3-0.1PbTiO3(PMN-PT), and SrBi2Ta2O9(SBT) are investigated using laser interferometry combined with conventional dielectric measurements. Effective electrostriction coefficients of the films, Qeff, are determined using a linearized electrostriction equation that couples longitudinal piezoelectric coefficient, d33, with the polarization and dielectric constant. It is shown that, in PZT films, electrostriction coefficients slightly increase with applied electric field, reflecting the weak contribution of non-180° domains to piezoelectric properties. In contrast, in PMN-PT and SBT films electrostriction coefficients are field independent, indicating the intrinsic nature of the piezoelectric response. The experimental values of Qeff are significantly smaller than those of corresponding bulk materials due to substrate clamping and possible size effects. Electrostriction coefficients of PZT layers are shown to depend strongly on the composition and preferred orientation of the grains. In particular, Qeff of (100) textured rhombohedral films (x=0.7) is significantly greater than that of (111) layers. Thus large anisotropy of the electrostrictive coefficients is responsible for recently observed large piezoelectric coefficients of (100) textured PZT films. Effective electrostriction coefficients obtained by laser interferometry allow evaluation of the electromechanical properties of ferroelectric films based solely on the dielectric parameters and thus are very useful in the design and fabrication of microsensors and microactuators.

Development and validation of attitudes towards Recovery Questionnaire across Chinese people in recovery, their family carers, and service providers in Hong Kong.

Science.gov (United States)

Mak, Winnie W S; Chan, Randolph C H; Yau, Sania S W

2018-05-29

Considering the lack of existing measures on attitudes toward personal recovery and the need to acknowledge the cultural milieu in recovery attitude assessment, the present study developed and validated the Attitudes towards Recovery Questionnaire (ARQ) in a sample of people in recovery of mental illness, family carers, and mental health service providers in Hong Kong. The ARQ was developed based on existing literature and measures of recovery, and focus group discussions with various stakeholders. Findings of the multi-sample confirmatory factor analyses supported a five-factor structure: (1) resilience as a person in recovery, (2) self-appreciation and development, (3) self-direction, (4) family involvement, and (5) social ties and integration. The ARQ was positively correlated with recovery outcomes, empowerment, recovery knowledge, and recovery orientation of mental health services. As a tool for examining recovery attitudes, the ARQ informs us of the mindset across stakeholders and areas that need enhancement to facilitate the recovery process. Copyright © 2018. Published by Elsevier B.V.

Table for constructing the spin coefficients in general relativity

International Nuclear Information System (INIS)

Cocke, W.J.

1989-01-01

The spin coefficients in spinor calculus in Riemannian space-time are linear functions of the curls of the connecting quantities (the Infeld--Van der Waerden symbols). We show that in the Newman-Penrose formalism the expressions for the spin coefficients are quite manageable, if they are written in terms of the Newman-Penrose tetrad vectors. We present a table of the components of the spin coefficients explicitly in terms of the curls of the individual tetrad vectors

Coefficients of viscosity for heavy impurity element in tokamak

Energy Technology Data Exchange (ETDEWEB)

El-Sharif, R N; Bekhit, A M [Plasma Physics dept., NRC, Atomic energy Authority, Cairo, (Egypt)

1997-12-31

The transport of heavy impurity element in to tokamak was studied theoretically. The viscosity coefficients of chromium impurities has been calculated in 13 and 21 moment approximation, in the limit of strong fields where is the gyrofrequency of species it was found that the off diagonal coefficient approximately tends to zero. This means that the friction force in the off-diagonal direction is very small, for the perpendicular viscosity coefficient the two approximation coincide to each other. 3 figs.

Leading a Recovery-oriented Social Enterprise.

Science.gov (United States)

Raeburn, Toby; Hungerford, Catherine; Sayers, Jan; Escott, Phil; Lopez, Violeta; Cleary, Michelle

2015-05-01

Recovery-oriented mental health services promote the principles of recovery, such as hope and optimism, and are characterized by a personalized approach to developing consumer self-determination. Nurse leaders are increasingly developing such services as social enterprises, but there is limited research on the leadership of these programs. Leading a recovery-oriented mental health nurse social enterprise requires visionary leadership, collaboration with consumers and local health providers, financial viability, and commitment to recovery-focused practice. This article describes the framework of an Australian mental health nursing social enterprise, including the service attributes and leadership lessons that have been learned from developing program sustainability.

Consideration on Singularities in Learning Theory and the Learning Coefficient

Directory of Open Access Journals (Sweden)

Miki Aoyagi

2013-09-01

Full Text Available We consider the learning coefficients in learning theory and give two new methods for obtaining these coefficients in a homogeneous case: a method for finding a deepest singular point and a method to add variables. In application to Vandermonde matrix-type singularities, we show that these methods are effective. The learning coefficient of the generalization error in Bayesian estimation serves to measure the learning efficiency in singular learning models. Mathematically, the learning coefficient corresponds to a real log canonical threshold of singularities for the Kullback functions (relative entropy in learning theory.

Quadrature formulas for Fourier coefficients

KAUST Repository

Bojanov, Borislav; Petrova, Guergana

2009-01-01

We consider quadrature formulas of high degree of precision for the computation of the Fourier coefficients in expansions of functions with respect to a system of orthogonal polynomials. In particular, we show the uniqueness of a multiple node

Statistical Study of Turbulence: Spectral Functions and Correlation Coefficients

Science.gov (United States)

Frenkiel, Francois N.

1958-01-01

In reading the publications on turbulence of different authors, one often runs the risk of confusing the various correlation coefficients and turbulence spectra. We have made a point of defining, by appropriate concepts, the differences which exist between these functions. Besides, we introduce in the symbols a few new characteristics of turbulence. In the first chapter, we study some relations between the correlation coefficients and the different turbulence spectra. Certain relations are given by means of demonstrations which could be called intuitive rather than mathematical. In this way we demonstrate that the correlation coefficients between the simultaneous turbulent velocities at two points are identical, whether studied in Lagrange's or in Euler's systems. We then consider new spectra of turbulence, obtained by study of the simultaneous velocities along a straight line of given direction. We determine some relations between these spectra and the correlation coefficients. Examining the relation between the spectrum of the turbulence measured at a fixed point and the longitudinal-correlation curve given by G. I. Taylor, we find that this equation is exact only when the coefficient is very small.

Similarity analysis between chromosomes of Homo sapiens and monkeys with correlation coefficient, rank correlation coefficient and cosine similarity measures

OpenAIRE

Someswara Rao, Chinta; Viswanadha Raju, S.

2016-01-01

In this paper, we consider correlation coefficient, rank correlation coefficient and cosine similarity measures for evaluating similarity between Homo sapiens and monkeys. We used DNA chromosomes of genome wide genes to determine the correlation between the chromosomal content and evolutionary relationship. The similarity among the H. sapiens and monkeys is measured for a total of 210 chromosomes related to 10 species. The similarity measures of these different species show the relationship b...

A Note on the Correlated Random Coefficient Model

DEFF Research Database (Denmark)

Kolodziejczyk, Christophe

In this note we derive the bias of the OLS estimator for a correlated random coefficient model with one random coefficient, but which is correlated with a binary variable. We provide set-identification to the parameters of interest of the model. We also show how to reduce the bias of the estimator...

Energy-neutral sustainable nutrient recovery incorporated with the wastewater purification process in an enlarged microbial nutrient recovery cell

Science.gov (United States)

Sun, Dongya; Gao, Yifan; Hou, Dianxun; Zuo, Kuichang; Chen, Xi; Liang, Peng; Zhang, Xiaoyuan; Ren, Zhiyong Jason; Huang, Xia

2018-04-01

Recovery of nutrient resources from the wastewater is now an inevitable strategy to maintain the supply of both nutrient and water for our huge population. While the intensive energy consumption in conventional nutrient recovery technologies still remained as the bottleneck towards the sustainable nutrient recycle. This study proposed an enlarged microbial nutrient recovery cell (EMNRC) which was powered by the energy contained in wastewater and achieved multi-cycle nutrient recovery incorporated with in situ wastewater treatment. With the optimal recovery solution of 3 g/L NaCl and the optimal volume ratio of wastewater to recovery solution of 10:1, >89% of phosphorus and >62% of ammonium nitrogen were recovered into struvite. An extremely low water input ratio of water. It was proved the EMNRC system was a promising technology which could utilize the chemical energy contained in wastewater itself and energy-neutrally recover nutrient during the continuous wastewater purification process.

Recovery post treatment: plans, barriers and motivators.

Science.gov (United States)

Duffy, Paul; Baldwin, Helen

2013-01-30

The increasing focus on achieving a sustained recovery from substance use brings with it a need to better understand the factors (recovery capital) that contribute to recovery following treatment. This work examined the factors those in recovery perceive to be barriers to (lack of capital) or facilitators of (presence of capital) sustained recovery post treatment. A purposive sample of 45 participants was recruited from 11 drug treatment services in northern England. Semi-structured qualitative interviews lasting between 30 and 90 minutes were conducted one to three months after participants completed treatment. Interviews examined key themes identified through previous literature but focused on allowing participants to explore their unique recovery journey. Interviews were transcribed and analysed thematically using a combination of deductive and inductive approaches. Participants generally reported high levels of confidence in maintaining their recovery with most planning to remain abstinent. There were indications of high levels of recovery capital. Aftercare engagement was high, often through self referral, with non substance use related activity felt to be particularly positive. Supported housing was critical and concerns were raised about the ability to afford to live independently with financial stability and welfare availability a key concern in general. Employment, often in the substance use treatment field, was a desire. However, it was a long term goal, with substantial risks associated with pursuing this too early. Positive social support was almost exclusively from within the recovery community although the re-building of relationships with family (children in particular) was a key motivator post treatment. Addressing internal factors and underlying issues i.e. 'human capital', provided confidence for continued recovery whilst motivators focused on external factors such as family and maintaining aspects of a 'normal' life i.e. 'social and physical

Recovery post treatment: plans, barriers and motivators

Directory of Open Access Journals (Sweden)

Duffy Paul

2013-01-01

Full Text Available Abstract Background The increasing focus on achieving a sustained recovery from substance use brings with it a need to better understand the factors (recovery capital that contribute to recovery following treatment. This work examined the factors those in recovery perceive to be barriers to (lack of capital or facilitators of (presence of capital sustained recovery post treatment. Methods A purposive sample of 45 participants was recruited from 11 drug treatment services in northern England. Semi-structured qualitative interviews lasting between 30 and 90 minutes were conducted one to three months after participants completed treatment. Interviews examined key themes identified through previous literature but focused on allowing participants to explore their unique recovery journey. Interviews were transcribed and analysed thematically using a combination of deductive and inductive approaches. Results Participants generally reported high levels of confidence in maintaining their recovery with most planning to remain abstinent. There were indications of high levels of recovery capital. Aftercare engagement was high, often through self referral, with non substance use related activity felt to be particularly positive. Supported housing was critical and concerns were raised about the ability to afford to live independently with financial stability and welfare availability a key concern in general. Employment, often in the substance use treatment field, was a desire. However, it was a long term goal, with substantial risks associated with pursuing this too early. Positive social support was almost exclusively from within the recovery community although the re-building of relationships with family (children in particular was a key motivator post treatment. Conclusions Addressing internal factors and underlying issues i.e. ‘human capital’, provided confidence for continued recovery whilst motivators focused on external factors such as family and

The Vessel Schedule Recovery Problem

DEFF Research Database (Denmark)

Brouer, Berit Dangaard; Plum, Christian Edinger Munk; Vaaben, Bo

Maritime transportation is the backbone of world trade and is accountable for around 3% of the worlds CO2 emissions. We present the Vessel Schedule Recovery Problem (VSRP) to evaluate a given disruption scenario and to select a recovery action balancing the trade off between increased bunker cons...... consumption and the impact on the remaining network and the customer service level. The model is applied to 4 real cases from Maersk Line. Solutions are comparable or superior to those chosen by operations managers. Cost savings of up to 58% may be achieved.......Maritime transportation is the backbone of world trade and is accountable for around 3% of the worlds CO2 emissions. We present the Vessel Schedule Recovery Problem (VSRP) to evaluate a given disruption scenario and to select a recovery action balancing the trade off between increased bunker...

Recovery of Areas Degraded by Mining Within the Amazon Forest: Interaction of the Physical Condition of Soil and Biological Activity

Science.gov (United States)

Ribeiro, A. I.; Mello, G. F.; Longo, R. M.; Fengler, F. H.; Peche Filho, A., Sr.

2017-12-01

One of the greatest natural riches of Brazil is the Amazon rainforest. The Amazon region is known for its abundance of mineral resources, and may include topaz, oil, and especially cassiterite. In this scope, the mining sector in Brazil has great strategic importance because it accounts for approximately 30% of the country's exports with a mineral production of 40 billion dollars (Brazilian Mining Institute, 2015). In this scenario, as a consequence of mining, the Amazonian ecosystem has been undergoing a constant process of degradation. An important artifice in the exploitation of mineral resources is the rehabilitation and/or recovery of degraded areas. This recovery requires the establishment of degradation indicators and also the quality of the soil associated with its biota, since the Amazonian environment is dynamic, heterogeneous and complex in its physical, chemical and biological characteristics. In this way, this work presupposes that it is possible to characterize the different stages of recovery of tillage floor areas in deactivated cassiterite mines, within the Amazonian forest, in order to evaluate the interactions between the level of biological activity (Serrapilheira Height, Coefficient Metabolic, Basal Breath) and physical soil characteristics (aggregate DMG, Porosity, Total Soil Density, Moisture Content), through canonical correlation analysis. The results present correlations between the groups of indicators. Thus, from the use of the groups defined by canonical correlations, it was possible to identify the response of the set of physical and biological variables to the areas at different stages of recovery.

Limits of the memory coefficient in measuring correlated bursts

Science.gov (United States)

Jo, Hang-Hyun; Hiraoka, Takayuki

2018-03-01

Temporal inhomogeneities in event sequences of natural and social phenomena have been characterized in terms of interevent times and correlations between interevent times. The inhomogeneities of interevent times have been extensively studied, while the correlations between interevent times, often called correlated bursts, are far from being fully understood. For measuring the correlated bursts, two relevant approaches were suggested, i.e., memory coefficient and burst size distribution. Here a burst size denotes the number of events in a bursty train detected for a given time window. Empirical analyses have revealed that the larger memory coefficient tends to be associated with the heavier tail of the burst size distribution. In particular, empirical findings in human activities appear inconsistent, such that the memory coefficient is close to 0, while burst size distributions follow a power law. In order to comprehend these observations, by assuming the conditional independence between consecutive interevent times, we derive the analytical form of the memory coefficient as a function of parameters describing interevent time and burst size distributions. Our analytical result can explain the general tendency of the larger memory coefficient being associated with the heavier tail of burst size distribution. We also find that the apparently inconsistent observations in human activities are compatible with each other, indicating that the memory coefficient has limits to measure the correlated bursts.

Relativistic neoclassical transport coefficients with momentum correction

International Nuclear Information System (INIS)

Marushchenko, I.; Azarenkov, N.A.

2016-01-01

The parallel momentum correction technique is generalized for relativistic approach. It is required for proper calculation of the parallel neoclassical flows and, in particular, for the bootstrap current at fusion temperatures. It is shown that the obtained system of linear algebraic equations for parallel fluxes can be solved directly without calculation of the distribution function if the relativistic mono-energetic transport coefficients are already known. The first relativistic correction terms for Braginskii matrix coefficients are calculated.

On computing Laplace's coefficients and their derivatives.

Science.gov (United States)

Gerasimov, I. A.; Vinnikov, E. L.

The algorithm of computing Laplace's coefficients and their derivatives is proposed with application of recurrent relations. The A.G.M.-method is used for the calculation of values L0(0), L0(1). The FORTRAN-program corresponding to the algorithm is given. The precision control was provided with numerical integrating by Simpsons method. The behavior of Laplace's coefficients and their third derivatives whith varying indices K, n for fixed values of the α-parameter is presented graphically.

Controller recovery from equipment failures in air traffic control: A framework for the quantitative assessment of the recovery context

International Nuclear Information System (INIS)

Subotic, Branka; Schuster, Wolfgang; Majumdar, Arnab; Ochieng, Washington

2014-01-01

Air Traffic Control (ATC) involves a complex interaction of human operators (primarily air traffic controllers), equipment and procedures. On the rare occasions when equipment malfunctions, controllers play a crucial role in the recovery process of the ATC system for continued safe operation. Research on human performance in other safety critical industries using human reliability assessment techniques has shown that the context in which recovery from failures takes place has a significant influence on the outcome of the process. This paper investigates the importance of context in which air traffic controller recovery from equipment failures takes place, defining it in terms of 20 Recovery Influencing Factors (RIFs). The RIFs are used to develop a novel approach for the quantitative assessment of the recovery context based on a metric referred to as the Recovery Context Indicator (RCI). The method is validated by a series of simulation exercises conducted at a specific ATC Centre. The proposed method is useful to assess recovery enhancement approaches within ATC centres

Brain Pathways to Recovery from Alcohol Dependence

Science.gov (United States)

Cui, Changhai; Noronha, Antonio; Warren, Kenneth; Koob, George F.; Sinha, Rajita; Thakkar, Mahesh; Matochik, John; Crews, Fulton T.; Chandler, L. Judson; Pfefferbaum, Adolf; Becker, Howard C.; Lovinger, David; Everitt, Barry; Egli, Mark; Mandyam, Chitra; Fein, George; Potenza, Marc N.; Harris, R. Adron; Grant, Kathleen A.; Roberto, Marisa; Meyerhoff, Dieter J.; Sullivan, Edith V.

2015-01-01

This article highlights the research presentations at the satellite symposium on “Brain Pathways to Recovery from Alcohol Dependence” held at the 2013 Society for Neuroscience Annual Meeting. The purpose of this symposium was to provide an up to date overview of research efforts focusing on understanding brain mechanisms that contribute to recovery from alcohol dependence. A panel of scientists from the alcohol and addiction research field presented their insights and perspectives on brain mechanisms that may underlie both recovery and lack of recovery from alcohol dependence. The four sessions of the symposium encompassed multilevel studies exploring mechanisms underlying relapse and craving associated with sustained alcohol abstinence, cognitive function deficit and recovery, and translational studies on preventing relapse and promoting recovery. Gaps in our knowledge and research opportunities were also discussed. PMID:26074423

Experimental and numerical modeling of heavy-oil recovery by electrical heating

Energy Technology Data Exchange (ETDEWEB)

Hascakir, B.; Akin, S. [Middle East Technical Univ., Ankara (Turkey); Babadagli, T. [Alberta Univ., Edmonton, AB (Canada)

2008-10-15

This study examined the applicability of electrical heating as a heavy oil recovery system in 2 heavy oil fields in Turkey. The physical and chemical properties of samples from the 2 fields were compiled and measured. The samples were then subjected to electrical heating. A retort technique was used to determine oil recovery performance under various conditions. Different types of iron powders were also applied in order to reduce oil viscosity. In situ viscosity reduction levels during the heating process were measured using a history matching procedure that considered data obtained during the laboratory experiments. The study demonstrated that the addition of iron power to the oil samples caused the polar components of the oil to decrease. Oil viscosity was strongly influenced by the magnetic fields created by the iron powders. An analysis of the experimental data showed that significant viscosity reductions of 88 per cent were obtained for the samples when iron additions of 0.5 per cent were used. Data from the experiments were used to develop mathematical models in order to consider thermal diffusion coefficients, oil viscosity, and relative permeability parameters. It was concluded that the cost of producing 1 barrel of oil using the method cost approximately US $5. After a period of 70 days, 320 barrels of petroleum were produced using the method. Oil production rates increased to 440 barrels over the same time period when iron additions were used. 30 refs., 6 tabs., 12 figs.

Curvature of Indoor Sensor Network: Clustering Coefficient

Directory of Open Access Journals (Sweden)

2009-03-01

Full Text Available We investigate the geometric properties of the communication graph in realistic low-power wireless networks. In particular, we explore the concept of the curvature of a wireless network via the clustering coefficient. Clustering coefficient analysis is a computationally simplified, semilocal approach, which nevertheless captures such a large-scale feature as congestion in the underlying network. The clustering coefficient concept is applied to three cases of indoor sensor networks, under varying thresholds on the link packet reception rate (PRR. A transition from positive curvature (“meshed” network to negative curvature (“core concentric” network is observed by increasing the threshold. Even though this paper deals with network curvature per se, we nevertheless expand on the underlying congestion motivation, propose several new concepts (network inertia and centroid, and finally we argue that greedy routing on a virtual positively curved network achieves load balancing on the physical network.

General introduction and recovery factors