Uranium-bearing wastes and their radon emanation

International Nuclear Information System (INIS)

Sasaki, Tomozo; Imamura, Mitsutaka; Gunji, Yasuyoshi

2007-01-01

There are no data available with regard to radon emanation coefficients for uranium-bearing wastes; such data are needed for the assessment of radiation exposure from radon that will be generated in the distant future as one uranium progeny at shallow land disposal sites for uranium-bearing wastes. There are many kinds of uranium-bearing wastes. However, it is not necessary to measure the radon emanation coefficients for all of them for two reasons. First, the radon emanation coefficients for uranium-bearing wastes contaminated by dissolved uranium are determined by the uranium chemical form, the manner of uranium deposition on the waste matrix, and the size of the particles which constitute the waste matrix. Therefore, only a few representative measurements are sufficient for such uranium-bearing wastes. Second, it is possible to make theoretical calculations of radon emanation coefficients for uranium-bearing wastes contaminated by UO 2 particles before sintering. In the present study, simulated uranium-bearing wastes contaminated by dissolved uranium were prepared, their radon emanation coefficients were measured and radon emanation coefficients were calculated theoretically for uranium-bearing wastes contaminated by UO 2 particles before sintering. The obtained radon emanation coefficients are distributed at higher values than those for ubiquitous soils and rocks in the natural environment. Therefore, it is not correct to just compare uranium concentrations among uranium-bearing wastes, ubiquitous soils and rocks in terms of radiation exposure. The radon emanation coefficients obtained in the present study have to be employed together with the uranium concentration in uranium-bearing wastes in order to achieve proper assessment of radiation exposure. (author)

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)

Study of radon emanation from uranium mill tailings. Relations between radon emanating power and physicochemical properties of the material

International Nuclear Information System (INIS)

Pellegrini, D.

1999-01-01

The uranium extraction from ores leads to large amounts of mill tailings still containing radionuclides, such as thorium-230 and radium-226, which generate radon-222. Without protective action, radon exposition may be high enough to cause concern for health of populations living in the vicinity of an uranium mill tailings disposal. This exposition pathway has therefore to be taken into account in the radiological impact studies. The emanating power, i.e. the part of radon atoms which escape from the solid particles, is directly involved in the radon source term evaluation. It may be determined for a given material by laboratory measurements. Emanating powers from 0.08 to 0.33 have been obtained for mill tailings from Jouac (Limousin, France), at various moisture contents. In order to reduce the relations of dependence between some of the emanation parameters, more simple phases, kaolinite and polymeric resins, have been studied. Those experiments have led us to the selection of the mechanisms and the parameters to consider for the development of an emanation modelling. The whole of the results obtained point out the radon sorption, in various proportions depending on the materials. The moisture content influence on the emanation from materials containing fine particles have been confirmed: the emanation increases with this parameter until a continuous water film surrounding the particles have been formed, and then become constant. This 'water effect' occurs in a moisture content range, which depends on the material porosity. Elsewhere, the presence of amorphous phases may led to a high radon emanation. (author)

Radioactive emanations in fumarole gases of a series of volcanoes in Kamchatka

International Nuclear Information System (INIS)

Adamchuk, Yu.V.; Firstov, P.P.

1986-01-01

The results of measurements of volume activity of emanations in fumarole gases of a series of acting volcanoes in Kamchatka during 1980-1983 are presented. The value of radon concentration in Avachinski volcano fumaroles equal ∼ 2 emanes did not change substantially as compared with the data for 1966. The highest activity (11.5±0.4 emanes) is registered in the Bezymyannyj volcano fumaroles. The emanation site survey of fumarole fields of the second cone of the Great fractured Tolbachinski eruption (GFTE) revealed the narrowly localized zone of radioactive emanation emissions. The radon emission in the above zone in 1981 constitutes (2.3 ± 0.4)x10 -6 Ci/s. Using this estimation, time (34-42 days) and average rate (2.5-3.0 m/h) of depth gases hoisting from magmatic focus are calculated as well as filtration rock characteristics in the narrowly localized near-mouth zone of the second cone of GCTE North outburst in the post eruptive period: permeability coefficient (0.1-4.3 darci), porosity (3-15 %) and mean value of cracks and pores opening (0.6-2.0)x10 -3 cm). The found characteristic values proved to be compared with parameters of crushing zone near epicenters of underground nuclear explosions

Exposure emanation methods of prospecting for mineral deposits

International Nuclear Information System (INIS)

Titov, V.L.; Venkov, V.A.; Avdeeva, T.Ya.; Kuvshinnikova, E.I.

1985-01-01

Fundamentals of the theory and practice of new methods for prospecting of mineral deposits-exposure emanation surveys are stated. Different modifications of these methods are considered: emanation track method, electron alphametry, technique based on the recording of alpha radiation of radon daughter products and thermoluminescent dosemeters. Advanatges of these methods as compared with the conventional emanation survey using emanometers and methods based on the recording of gamma radiation intensity are shown. Problems of the theory and practical aspects of the concrete modifications application as well as systems for data acquisition and processing fields of the methods application, technique of works performance and survey data interpretation are considered in detail; methods sensitivity, probable mechanisms of radon transport in bowels, role of a depth component of the radiactive emanation concentration field are evaluated. Examples of the method application in practice are given, emanation anomalies and their evaluation methods are classified

Emanation of 232U and its radioactive daughter products from respirable size particles

International Nuclear Information System (INIS)

Cuddihy, R.G.; Griffith, W.C.; Hoover, M.D.; Kanapilly, G.M.; Stalnaker, N.D.

1978-01-01

This study is to develop a model for the emanation of 232 U and its radioactive daughter products from particles of Th-U fuel material. The radiation doses to internal organs following inhalation of these particles can only be calculated by knowing the rate of emanation of the daughters from particles in the lung and the subsequent excretion or translocation of the daughters to other organs. The emanation mechanisms are recoil of the daughter nuclei from the particle during alpha decay of the parent, diffusion of inert gas daughters from the particle and dissolution of the particle itself in biological fluids. Experiments to evaluate these mechanisms will involve ThO 2 and UO 2 particles in the size range 0.1 to 1.0 μm MMAD uniformly labeled with 232 U. The influence of the material temperature history on emanation will be investigated by heat treating particles at 600 and 1400 0 C

Radon emanation in tectonically active areas

International Nuclear Information System (INIS)

King, C.Y.

1980-01-01

Subsurface radon emanation has been continuously monitored for up to three years by the Track Etch method in shallow dry holes at more than 60 sites along several tectonic faults in central California and at 9 sites near the Kilauea volcano in Hawaii. The measured emanation in these tectonically active areas shows large long-term variations that may be related mainly to crustal strain changes

Emanations and 'induced' radioactivity: from mystery to (mis)use

International Nuclear Information System (INIS)

Kolar, Z.I.

1999-01-01

The natural Rn isotopes were discovered within the period 1899-1902 and at that time referred to as emanations because they came out (emanated) of sources/materials containing actinium, thorium and radium, respectively. The (somewhat mysterious) emanations appeared to disintegrate into radioactive decay products which by depositing at solid surfaces gave rise to 'induced' radioactivity i.e. radioactive substances with various half-lives. Following the discovery of the emanations the volume of the research involving them and their disintegration products grew steeply. The identity of a number of these radioactive products was soon established. Radium emanation was soon used as a source of RaD ( 210 Pb) to be applied as an 'indicator' (radiotracer) for lead in a study on the solubility of lead sulphide and lead chromate. Moreover, radium and its emanation were introduced into the medical practice. Inhaling radon and drinking radon-containing water became an accepted medicinal use (or misuse?) of that gas. Shortly after the turn of the century, the healing (?) action of natural springs (spas) was attributed to their radium emanation, i.e. radon. Bathing in radioactive spring water and drinking it became very popular. Even today, bathing in radon-containing water is still a common medical treatment in Jachymov, Czech Republic. (author)

The radium distribution in some Swedish soils and its effects on radon emanation

International Nuclear Information System (INIS)

Edsfeldt, Cecilia

2001-08-01

The aim of this study has been to clarify how the radium distribution in soils affects the radon emanation. The distribution of radium, uranium and thorium has been determined using sequential extractions. In the study, soils from two different locations were investigated. In the first part the applicability of the sequential extraction method for determining Ra distribution in different soil types was investigated, using a simple sequential extraction method. Sampled soils were clay, sand and till from the vicinity of the Stockholm Esker. The main part of Rn emanating Ra was associated with Fe oxides in the soil. The methods applied provided information about the radon risk of the soil, but, in order to gain more information on the processes governing Ra distribution and radon emanation in soils, a more detailed sequential extraction procedure would be desirable. The second part consisted of a detailed study of the radionuclide distribution and the geochemistry in a podzolised glacial till from Kloten in northern Vaestmanland. A more detailed sequential extraction procedure was used, and the specific surface area of samples was measured. Samples were taken from E, B, and C horizons; radium and thorium were enriched in the B horizon, whereas uranium had its maximum concentration in the C horizon. Extractable radium primarily occurred in the exchangeable pool, possibly organically complexed, whereas extractable uranium and thorium were mainly Fe oxide bound. Oxide-bound Ra was important only in the B horizon. The radon emanation was not correlated with the amount of exchangeable Ra, but instead with the oxide bound Ra. However, the amount of oxide-bound Ra was too small to account for all the emanated Rn, thus, exchangeable Ra was interpreted as the main source of emanated Rn. This exchangeable Ra was more emanative in the B horizon than in the C horizon. The explanation is the larger surface area of the B horizon samples; the specific surface area appears to be the

Detailed effects of particle size and surface area on 222Rn emanation of a phosphate rock.

Science.gov (United States)

Haquin, Gustavo; Yungrais, Zohar; Ilzycer, Danielle; Zafrir, Hovav; Weisbrod, Noam

2017-12-01

The dependency of radon emanation on soil texture was investigated using the closed chamber method. Ground phosphate rock with a large specific surface area was analyzed, and the presence of inner pores, as well as a high degree of roughness and heterogeneity in the phosphate particles, was found. The average radon emanation of the dry phosphate was 0.145 ± 0.016. The emanation coefficient was highest (0.169 ± 0.019) for the smallest particles (210 μm). The reduction rate followed an inverse power law. As expected, a linear dependence between the emanation coefficient and the specific surface area was found, being lower than predicted for the large specific surface area. This was most likely due to an increase in the embedding effect of radon atoms in adjacent grains separated by micropores. Results indicate that knowledge of grain radium distribution is crucial to making accurate emanation predictions. Copyright © 2017 Elsevier Ltd. All rights reserved.

The use of emanation thermal analysis for the evaluation of Fe2O3 reactivity

International Nuclear Information System (INIS)

Balek, V.

1977-01-01

The ETA method using 220 Rn was applied in studying the ZnO - Fe 2 O 3 reaction. The higher is the temperature at which the maximum is reached on the emanation vs. temperature curve of the mixture, the lower the indicated reactivity of Fe 2 O 3 used (temperature range 790 to 980 degC). The degree of order in the lattice of the ZnFe 2 O 4 formed may be judged from the emanation power at 850 to 1000 degC. Fe 2 O 3 pre-annealed to 1100 degC shows the lowest reactivity with ZnO. Associated with it is a lower capacity of forming the perfect ZnFe 2 O 4 structure. The ETA results are compared with those obtained by DTA and by dilatometry. (M.K.)

Study of radon emanation from uranium mill tailings. Relations between radon emanating power and physicochemical properties of the material; Etude de l'emanation du radon a partir de residus de traitement de minerais d'uranium. Mise en evidence de relations entre le facteur d'emanation et les caracteristiques du materiau

Energy Technology Data Exchange (ETDEWEB)

Pellegrini, D

1999-07-01

The uranium extraction from ores leads to large amounts of mill tailings still containing radionuclides, such as thorium-230 and radium-226, which generate radon-222. Without protective action, radon exposition may be high enough to cause concern for health of populations living in the vicinity of an uranium mill tailings disposal. This exposition pathway has therefore to be taken into account in the radiological impact studies. The emanating power, i.e. the part of radon atoms which escape from the solid particles, is directly involved in the radon source term evaluation. It may be determined for a given material by laboratory measurements. Emanating powers from 0.08 to 0.33 have been obtained for mill tailings from Jouac (Limousin, France), at various moisture contents. In order to reduce the relations of dependence between some of the emanation parameters, more simple phases, kaolinite and polymeric resins, have been studied. Those experiments have led us to the selection of the mechanisms and the parameters to consider for the development of an emanation modelling. The whole of the results obtained point out the radon sorption, in various proportions depending on the materials. The moisture content influence on the emanation from materials containing fine particles have been confirmed: the emanation increases with this parameter until a continuous water film surrounding the particles have been formed, and then become constant. This 'water effect' occurs in a moisture content range, which depends on the material porosity. Elsewhere, the presence of amorphous phases may led to a high radon emanation. (author)

Emanation of radon-222 in uraniferous phosphorite from Pernambuco, Brazil

International Nuclear Information System (INIS)

Santos, M.L.O.; França, E.J.; Amaral, D.S.; Silva, K.E.M.; Hazin, C.A.; Farias, E.E.G.

2017-01-01

The concentration of radon-222 activity available for transport to the surface through the pore space can be defined as radon emanation. From the decay of radium-226, whose half-life is 1850 years, it is associated with the development of neoplasia, such as lung cancer. In the Metropolitan Region of Recife, sedimentary rocks known as phosphorites have been known since 1959, so, from the radiometric characterization of the Paulista and Igarassu Municipality, in Pernambuco, emanation tests were carried out, aiming to determine the emanation power of radon in samples of uraniferous phosphorite from the Recife Metropolitan Region. Initially, 6 independent samples of phosphorites with activity concentration of 226 Ra> 400 Bq kg -1 were comminuted. Portions of 5g were conditioned in a radon chamber with 500 mL volume for measurements. The linear fit of the model converged after 200 interactions with selection of the best fit by the Chi-Square test, through the Origin® 8.0 program. After analysis of the samples, radon emanation power was estimated in the range of 7% to 15%, with a mean value of 10.8%. The methodology used to determine the emanation parameters in samples of uraniferous phosphorite was adequate, observing an inversely proportional relation between the concentration of the radium-226 and the emanation power

Present knowledge of the effect of cracks on radon emanation from tailings, with implications for mine rehabilitation at Olympic Dam

International Nuclear Information System (INIS)

Storm, J.R.; Patterson, J.R.

1997-01-01

The weather parameters of air pressure, temperature, rainfall and wind speed affect the rate of radon-222 emanation from the surface of mine tailings. A second set of conditions which form cracks or fissures in tailings and their covers, will also affect the radon flux density and they must be considered in the design of any cover for a rehabilitation program. The Olympic Dam mine expansion program, beginning in 1995, involves a substantial increase in the size of the copper/uranium tailings. As part of monitoring and progressive rehabilitation of the tailings, the rate of emanation of radon-222 from tailings' surfaces was measured, with and without the gross defects of cracking. Theoretical predictions and measurements made in the U.S., are compared with rates of emanation from a cracked surface, modelled as homogeneous with additional surface area due to cracks

Exercise-induced maximum metabolic rate scaled to body mass by ...

African Journals Online (AJOL)

Exercise-induced maximum metabolic rate scaled to body mass by the fractal ... rate scaling is that exercise-induced maximum aerobic metabolic rate (MMR) is ... muscle stress limitation, and maximized oxygen delivery and metabolic rates.

Study of radon emanation variations in Morocco soil, correlations with seismic activities and atmospheric parameters

International Nuclear Information System (INIS)

Boukhal, H.; Cherkaoui, T.E.; Lferde, M.

1994-01-01

In order to verify the possibility of radon signal use in earthquake prediction, a study of radon emanation variation in soil was undertaken. Regular measurements have been carried out in five cities of Morocco ( Rabat, Tetouan, Ifrane, Khouribga, Berchid). The measuring method is based on the solid state nuclear track detectors technique. The good correlation between the different seismic activities and the variations of radon emanation rate in the five stations, have shown the interest of radon use in the earthquake prediction. 1 tab., 2 figs., 2 refs. (author)

Measurement of radon emanation of drainage layer media by liquid scintillation counting

International Nuclear Information System (INIS)

Turtiainen, T.

2009-01-01

Slab-on-ground is a typical base floor construction type in Finland. The drainage layer between the slab and soil is a layer of sand, gravel or crushed stone. This layer has a minimum thickness of 200 mm and is sometimes even 600 mm thick, and thus may be a significant contributor to indoor air radon. In order to investigate radon emanation from the drainage layer material, a simple laboratory test was developed. Many organic solvents have high Ostwald coefficients for radon, i.e., the ratio of the volume of gas absorbed to the volume of the absorbing liquid, which enables direct absorption of radon into a liquid scintillation cocktail. Here, we first present equations relating to the processes of gas transfer in emanation measurement by direct absorption into liquid scintillation cocktails. In order to optimize the method for emanation measurement, four liquid scintillation cocktails were assessed for their ability to absorb radon from air. A simple apparatus consisting of a closed glass container holding an open liquid scintillation vial was designed and the diffusion/absorption rate and Ostwald coefficient were determined for a selected cocktail. Finally, a simple test was developed based on this work. (author)

Study of radon-222 emanation from sedimentary phosphates and corresponding phosphogypsum. Temperature effect

International Nuclear Information System (INIS)

Boujrhal, F.M.

1993-01-01

The aim of this study is to examine the effect of temperature on radon emanation from the phosphates of various regions of Morocco, from corresponding phosphogypsum and from teeth fossilized of Youssoufia phosphate. The interpretation of obtained results was carried out by the physicochemical studies with various approaches; the X-ray diffraction analysis, the measurement of the specific surface area and porousness, the determination of the oxygen content by activation analysis with 14 MeV neutron. The thermal treatment between 100 and 900 degrees C conducted to the following points: - An increase of the radon degassing rate, which is first slow when the temperature increase from 20 to 600 degrees C, then becomes brutal beyond this temperature. We attributed this variation to the training effect ( transport effect ) of radon by the others gas susceptible to be released with thermal effect, particularly the CO sub 2. - The reduction of the radon emanation power versus temperature. We could demonstrate a linear correlation between the power emanation and the specific surface area. 122 refs., 102 figs., 20 tabs. (Author)

5 CFR 531.221 - Maximum payable rate rule.

Science.gov (United States)

2010-01-01

... before the reassignment. (ii) If the rate resulting from the geographic conversion under paragraph (c)(2... previous rate (i.e., the former special rate after the geographic conversion) with the rates on the current... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Maximum payable rate rule. 531.221...

Radon emanation on San Andreas Fault

International Nuclear Information System (INIS)

King, C.-Y.

1978-01-01

It is stated that subsurface radon emanation monitored in shallow dry holes along an active segment of the San Andreas fault in central California shows spatially coherent large temporal variations that seem to be correlated with local seismicity. (author)

Radon sources emanation in granitic soil and saprolite

Energy Technology Data Exchange (ETDEWEB)

Wollenberg, H.; Flexser, S. [Lawrence Berkeley Lab., CA (United States); Brimhall, G.; Lewis, C. [California Univ., Berkeley, CA (United States). Dept. of Geology and Geophysics

1993-08-01

Petrological and geochemical examinations of soil, saprolite, and quartz diorite protolith have been made at the Small Structures field site, Ben Lomond Mountain, California. Variations in Ra in soil and saprolite are mainly controlled by heterogeneities inherited from the parent quartz diorite. Fission-track radiography shows that U is concentrated in the primary accessory minerals, zircon and sphene. However, most importantly for Rn emanation, U is also concentrated in secondary sites: weathered sphene, biotite and plagioclase, grain coatings, and Fe-rich fracture linings which also contain a rare-earth phosphate mineral. This occurrence of U along permeable fracture zones suggests that soil-gas Rn from depth (> 2 m) is a significant contributor to Rn availability near the surface. Zones highest in emanation occur where fine pedogenic phases: gibbsite, amorphous silica, and iron oxyhydroxide are most abundant. Mass balance analyses of this soil-saprolite profile are in progress and preliminary indicate that a high-emanation zone corresponds to the upper portion of a zone of accumulation of U and Ba.

Evaluation of Information Leakage via Electromagnetic Emanation and Effectiveness of Tempest

Science.gov (United States)

Tanaka, Hidema

It is well known that there is relationship between electromagnetic emanation and processing information in IT devices such as personal computers and smart cards. By analyzing such electromagnetic emanation, eavesdropper will be able to get some information, so it becomes a real threat of information security. In this paper, we show how to estimate amount of information that is leaked as electromagnetic emanation. We assume the space between the IT device and the receiver is a communication channel, and we define the amount of information leakage via electromagnetic emanations by its channel capacity. By some experimental results of Tempest, we show example estimations of amount of information leakage. Using the value of channel capacity, we can calculate the amount of information per pixel in the reconstructed image. And we evaluate the effectiveness of Tempest fonts generated by Gaussian method and its threshold of security.

Estimation of radon emanation coefficient for soil and flyash

International Nuclear Information System (INIS)

Sahu, S.K.; Swarnkar, M.; Ajmal, P.Y.; Pandit, G.G.; Puranik, V.D.

2012-01-01

Since terrestrial materials include radium ( 226 Ra) originating from the decay of uranium ( 238 U), all such materials release radon ( 222 Rn) to varying degrees. When a radium atom decays to radon, the energy generated is strong enough to send the radon atom a distance of about 40 nanometers-this is known as alpha recoil. For a radon atom to escape the radium atom must be within the recoil distance from the grain surface of flyash or soil and the direction of recoil must send the radon atom toward the outside of the grain. Therefore, all of the radon atoms generated by the radium contained in flyash or soil grain are actually not released into pore spaces and mobilized. The fraction of radon atoms generated from radium decay that are released from into flyash or soil pore space is defined as the radon emanation coefficient or emanating power, of the material. Grain size and shape are two of the important factors that control the radon emanation coefficient because they determine in part how much uranium and radium is near enough to the surface of the grain to allow the newly-formed radon to escape into a pore space. In a porous medium, where the radon is in radioactive equilibrium with its parent radium, the emanation coefficient is given by the expression: where C 0 is the undiluted radon activity concentration in the pores of the medium, and C Ra is the radium activity concentration of the sample. The 226 Ra activity concentration of the flyash and soil sample were determined by using the g-spectrometry. C 0 was determined by the can experiment using LR-115 for flyash and soil samples. The C 0 values for flyash and soil samples were found to be 245.7 Bq/m 3 and 714.3 Bq/m 3 respectively. The radon emanation coefficient for flyash was found to be 0.0024 while that for soil was 0.0092. Therefore the soil sample was found to be four times higher radon emanation coefficient than flyash which is in line with the results reported in the literatures. This may suggest

Fractal theory of radon emanation from solids

International Nuclear Information System (INIS)

Semkow, T.M.

1991-01-01

The author developed a fractal theory of Rn emanation from solids, based on α recoil from the α decay of Ra. Range straggling of the recoiling Rn atoms in the solid state is included and the fractal geometry is used to describe the roughness of the emanating surface. A fractal dimension D of the surface and the median projected range become important parameters in calculating the radon emanating power E R from solids. A relation between E R and the specific surface area measured by the gas adsorption is derived for the first time, assuming a uniform distribution of the precursor Ra throughout the samples. It is suggested that the E R measurements can be used to determine D of the surfaces on the scale from tens to hundreds of nm. One obtains, for instance, D = 2.17 ± 0.06 for Lipari volcanic glass and D = 2.83 ± 0.03 for pitchblende. In addition, the author suggests a new process of penetrating recoil and modify the role of indirect recoil. The penetrating recoil may be important for rough surfaces, in which case Rn loses its kinetic energy by penetrating a large number of small surface irregularities. The indirect recoil may be important at the very last stage of energy-loss process, for kinetic energies below ∼ 5 keV

Dinosaur Metabolism and the Allometry of Maximum Growth Rate

OpenAIRE

Myhrvold, Nathan P.

2016-01-01

The allometry of maximum somatic growth rate has been used in prior studies to classify the metabolic state of both extant vertebrates and dinosaurs. The most recent such studies are reviewed, and their data is reanalyzed. The results of allometric regressions on growth rate are shown to depend on the choice of independent variable; the typical choice used in prior studies introduces a geometric shear transformation that exaggerates the statistical power of the regressions. The maximum growth...

44 CFR 208.12 - Maximum Pay Rate Table.

Science.gov (United States)

2010-10-01

...) Physicians. DHS uses the latest Special Salary Rate Table Number 0290 for Medical Officers (Clinical... Personnel, in which case the Maximum Pay Rate Table would not apply. (3) Compensation for Sponsoring Agency... organizations, e.g., HMOs or medical or engineering professional associations, under the revised definition of...

Study of 222Rn emanation levels present in naturally occurring radioactive materials - NORM

International Nuclear Information System (INIS)

Miranda, Marcia Valeria F.E. Sa; Crispim, Verginia Reis; Lima, Clara Teresa S.

2009-01-01

The presence of Naturally Occurring Radioactive Material (NORM), contaminating oil and gas installations, is usual in the petroleum industry, and can be severe enough to expose the workers to elevated levels of radiation. The segregation of contaminated residues although necessary, is still a problem without a satisfactory solution. Currently, the most practical and economic option for discarding this material is to stock it in areas of the installation with controlled access. Certain equipment used in the petroleum industry has scale and sludge that could be associated to important levels of radioactivity. Typically, the scales are mixtures of carbonate and sulphate minerals, such as barite (BaSO 4 ), that easily incorporate 226 Ra and 228 Ra in their structures. The objective of this work was to measure the emanations of the radon present in NORM samples, via diffusion chambers containing a nuclear track detector (CR-39). The images of α particle tracks emanated by 222 Rn registered on CR-39 were observed with a Nikon E400 optic microscope and captured by a Nikon Coolpix digital camera and then stored in a database, to later count the tracks using the computational program, Image Pro plus. Since the number of those tracks resulted proportional to the emanation rate of 222 Rn this methodology allowed the comparison of contamination levels in analyzed samples. (author)

Recalibration of the 226Ra emanation analysis system

International Nuclear Information System (INIS)

Lucas, H.F. Jr.; Markun, F.

1982-01-01

The 226 Ra emanation system was found to require recalibration. The gain of the various counting systems was established to about +-0.5%. The variance introduced into the analysis by multiple counting systems was low and corresponded to a fractional standard deviation of +-0.5%. The variance introduced into the analysis by both multiple counting systems and multiple counting chambers needs to be redetermined but is less than a fractional standard deviation of +-2%. The newly established calibration factor of 5.66 cpm/pg 226 Ra is about 6% greater than that used previously. The leakage of radon into the greased fittings of the emanation flask which was indicated in an earlier study was not confirmed

A comprehensive review of radon emanation measurements for mineral, rock, soil, mill tailing and fly ash

International Nuclear Information System (INIS)

Sakoda, Akihiro; Ishimori, Yuu; Yamaoka, Kiyonori

2011-01-01

To our knowledge, this paper is the most comprehensive review to cover most studies, published in the past three decades at least, of radon emanation measurements. The radon emanation fraction, a possibility of radon atoms generated in a material escaping from its grains, has been widely measured for a variety of materials. The aim of this review is to organize a huge number of such data accumulated. The representative values of the emanation fraction for minerals, rocks, soils, mill tailings and fly ashes were derived to be 0.03, 0.13, 0.20, 0.17 and 0.03, respectively. Current knowledge of the emanation processes was also summarized to discuss their affected factors. - Highlights: → Recent radon emanation measurements were thoroughly reviewed. → Averages of radon emanation fractions: 0.03 (mineral), 0.13 (rock), 0.20 (soil), 0.17 (mill tailing) and 0.03 (fly ash). → Grain-size effect was not significantly found for size larger than 1 μm. → Pore water generally enhances the emanation fraction by a factor of 5 or less. → Definition of 'radon emanation' should be shared among researchers.

Maximum organic carbon limits at different melter feed rates (U)

International Nuclear Information System (INIS)

Choi, A.S.

1995-01-01

This report documents the results of a study to assess the impact of varying melter feed rates on the maximum total organic carbon (TOC) limits allowable in the DWPF melter feed. Topics discussed include: carbon content; feed rate; feed composition; melter vapor space temperature; combustion and dilution air; off-gas surges; earlier work on maximum TOC; overview of models; and the results of the work completed

Dinosaur Metabolism and the Allometry of Maximum Growth Rate.

Science.gov (United States)

Myhrvold, Nathan P

2016-01-01

The allometry of maximum somatic growth rate has been used in prior studies to classify the metabolic state of both extant vertebrates and dinosaurs. The most recent such studies are reviewed, and their data is reanalyzed. The results of allometric regressions on growth rate are shown to depend on the choice of independent variable; the typical choice used in prior studies introduces a geometric shear transformation that exaggerates the statistical power of the regressions. The maximum growth rates of extant groups are found to have a great deal of overlap, including between groups with endothermic and ectothermic metabolism. Dinosaur growth rates show similar overlap, matching the rates found for mammals, reptiles and fish. The allometric scaling of growth rate with mass is found to have curvature (on a log-log scale) for many groups, contradicting the prevailing view that growth rate allometry follows a simple power law. Reanalysis shows that no correlation between growth rate and basal metabolic rate (BMR) has been demonstrated. These findings drive a conclusion that growth rate allometry studies to date cannot be used to determine dinosaur metabolism as has been previously argued.

Dinosaur Metabolism and the Allometry of Maximum Growth Rate

Science.gov (United States)

Myhrvold, Nathan P.

2016-01-01

The allometry of maximum somatic growth rate has been used in prior studies to classify the metabolic state of both extant vertebrates and dinosaurs. The most recent such studies are reviewed, and their data is reanalyzed. The results of allometric regressions on growth rate are shown to depend on the choice of independent variable; the typical choice used in prior studies introduces a geometric shear transformation that exaggerates the statistical power of the regressions. The maximum growth rates of extant groups are found to have a great deal of overlap, including between groups with endothermic and ectothermic metabolism. Dinosaur growth rates show similar overlap, matching the rates found for mammals, reptiles and fish. The allometric scaling of growth rate with mass is found to have curvature (on a log-log scale) for many groups, contradicting the prevailing view that growth rate allometry follows a simple power law. Reanalysis shows that no correlation between growth rate and basal metabolic rate (BMR) has been demonstrated. These findings drive a conclusion that growth rate allometry studies to date cannot be used to determine dinosaur metabolism as has been previously argued. PMID:27828977

47 CFR 1.1507 - Rulemaking on maximum rates for attorney fees.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 1 2010-10-01 2010-10-01 false Rulemaking on maximum rates for attorney fees... § 1.1507 Rulemaking on maximum rates for attorney fees. (a) If warranted by an increase in the cost of... types of proceedings), the Commission may adopt regulations providing that attorney fees may be awarded...

Theoretical concepts of fractal geometry semkow by radon emanation in solids

International Nuclear Information System (INIS)

Cruz G, H.

1996-01-01

The objective of this work is to introduce the fractal geometry concept to the study of gaseous emanations in solids, specially with reference to radon emission in mineral grains. The basic elements of fractals theory are developed. A fractal is defined as an auto similar subassembly, which fractal dimension is greater than the topological dimension. Starting from this, and making a brief description of the physicals basis of radon emission in solids, a model between emanation power (E R ) and the ratio s/v (surface to volume), is founded. A Gaussian model is assumed for extent of recoil from alpha decay of Ra-226. Using the results of Pfeifer it is obtained that distribution of pore size is scaled like Br -D-1 , where D: fractal[dimension, B: constant and r: pore radius. After an adequate mathematics expansion, it is found that the expression for emanation power is scaled like r 0 D-3 (r 0 grain radius). We may concluded that if we have a logarithmic graph of E R vs size of grain we can deduce the fractal dimension of the emanation surface. The experimental data of different materials provides an interval into fractal dimension D , between 2.1 to 2.86. (author). 5 refs., 1 tab

Radon Emanation from NORM-Contaminated Pipe Scale, Soil, and Sediment at Petroleum Industry Sites

International Nuclear Information System (INIS)

Rood, A.S.; White, G.J.

1999-01-01

This report describes a study of radon (Rn) emanation from pipe scale and soil samples contaminated with naturally occurring radioactive material (NORM). Samples were collected at petroleum production sites in Oklahoma, Michigan, Kentucky, and Illinois. For comparison, data are also presented from preliminary studies conducted at sites in Texas and Wyoming. All samples collected were analyzed for their Rn emanation fraction, defined as the fraction of 222Rn produced that enters the interconnected pore space within a medium contaminated with 226Ra before the 222Rn undergoes radioactive decay. This measure represents one of the important parameters that determine the overall Rn activity flux from any solid medium. The goal of this project was to determine whether Rn emanation from pipe scale and soil is similar to emanation from uranium mill tailings

A micromegas detector for {sup 222}Rn emanations measurements

Energy Technology Data Exchange (ETDEWEB)

García, J. A.; Garza, J. G.; Irastorza, I. G.; Mirallas, H. [Laboratorio de Física Nuclear y Altas Energías, Universidad de Zaragoza, Zaragoza (Spain)

2013-08-08

The {sup 222}Rn emanation has significant contribution in the overall background for rare event searches experiments. In order to measure this emanations a high sensitivity detector has been designed. The detection method is based on the electrostatic collection of the {sup 222}Rn daughters on a Micromegas detector. Using a chamber with a volume of 21.2 l for the collection of {sup 218}Po and {sup 214}Po progeny of {sup 222}Rn and a 12 × 12cm{sup 2} pixelized Micromegas for the α detection. The advantages of the Micromegas detectors are the low intrinsic radioactivity and the track reconstruction of the α’s, having excellent capabilities for event discrimination.

Allometries of Maximum Growth Rate versus Body Mass at Maximum Growth Indicate That Non-Avian Dinosaurs Had Growth Rates Typical of Fast Growing Ectothermic Sauropsids

Science.gov (United States)

Werner, Jan; Griebeler, Eva Maria

2014-01-01

We tested if growth rates of recent taxa are unequivocally separated between endotherms and ectotherms, and compared these to dinosaurian growth rates. We therefore performed linear regression analyses on the log-transformed maximum growth rate against log-transformed body mass at maximum growth for extant altricial birds, precocial birds, eutherians, marsupials, reptiles, fishes and dinosaurs. Regression models of precocial birds (and fishes) strongly differed from Case’s study (1978), which is often used to compare dinosaurian growth rates to those of extant vertebrates. For all taxonomic groups, the slope of 0.75 expected from the Metabolic Theory of Ecology was statistically supported. To compare growth rates between taxonomic groups we therefore used regressions with this fixed slope and group-specific intercepts. On average, maximum growth rates of ectotherms were about 10 (reptiles) to 20 (fishes) times (in comparison to mammals) or even 45 (reptiles) to 100 (fishes) times (in comparison to birds) lower than in endotherms. While on average all taxa were clearly separated from each other, individual growth rates overlapped between several taxa and even between endotherms and ectotherms. Dinosaurs had growth rates intermediate between similar sized/scaled-up reptiles and mammals, but a much lower rate than scaled-up birds. All dinosaurian growth rates were within the range of extant reptiles and mammals, and were lower than those of birds. Under the assumption that growth rate and metabolic rate are indeed linked, our results suggest two alternative interpretations. Compared to other sauropsids, the growth rates of studied dinosaurs clearly indicate that they had an ectothermic rather than an endothermic metabolic rate. Compared to other vertebrate growth rates, the overall high variability in growth rates of extant groups and the high overlap between individual growth rates of endothermic and ectothermic extant species make it impossible to rule out either

Allometries of maximum growth rate versus body mass at maximum growth indicate that non-avian dinosaurs had growth rates typical of fast growing ectothermic sauropsids.

Science.gov (United States)

Werner, Jan; Griebeler, Eva Maria

2014-01-01

We tested if growth rates of recent taxa are unequivocally separated between endotherms and ectotherms, and compared these to dinosaurian growth rates. We therefore performed linear regression analyses on the log-transformed maximum growth rate against log-transformed body mass at maximum growth for extant altricial birds, precocial birds, eutherians, marsupials, reptiles, fishes and dinosaurs. Regression models of precocial birds (and fishes) strongly differed from Case's study (1978), which is often used to compare dinosaurian growth rates to those of extant vertebrates. For all taxonomic groups, the slope of 0.75 expected from the Metabolic Theory of Ecology was statistically supported. To compare growth rates between taxonomic groups we therefore used regressions with this fixed slope and group-specific intercepts. On average, maximum growth rates of ectotherms were about 10 (reptiles) to 20 (fishes) times (in comparison to mammals) or even 45 (reptiles) to 100 (fishes) times (in comparison to birds) lower than in endotherms. While on average all taxa were clearly separated from each other, individual growth rates overlapped between several taxa and even between endotherms and ectotherms. Dinosaurs had growth rates intermediate between similar sized/scaled-up reptiles and mammals, but a much lower rate than scaled-up birds. All dinosaurian growth rates were within the range of extant reptiles and mammals, and were lower than those of birds. Under the assumption that growth rate and metabolic rate are indeed linked, our results suggest two alternative interpretations. Compared to other sauropsids, the growth rates of studied dinosaurs clearly indicate that they had an ectothermic rather than an endothermic metabolic rate. Compared to other vertebrate growth rates, the overall high variability in growth rates of extant groups and the high overlap between individual growth rates of endothermic and ectothermic extant species make it impossible to rule out either of

Allometries of maximum growth rate versus body mass at maximum growth indicate that non-avian dinosaurs had growth rates typical of fast growing ectothermic sauropsids.

Directory of Open Access Journals (Sweden)

Jan Werner

Full Text Available We tested if growth rates of recent taxa are unequivocally separated between endotherms and ectotherms, and compared these to dinosaurian growth rates. We therefore performed linear regression analyses on the log-transformed maximum growth rate against log-transformed body mass at maximum growth for extant altricial birds, precocial birds, eutherians, marsupials, reptiles, fishes and dinosaurs. Regression models of precocial birds (and fishes strongly differed from Case's study (1978, which is often used to compare dinosaurian growth rates to those of extant vertebrates. For all taxonomic groups, the slope of 0.75 expected from the Metabolic Theory of Ecology was statistically supported. To compare growth rates between taxonomic groups we therefore used regressions with this fixed slope and group-specific intercepts. On average, maximum growth rates of ectotherms were about 10 (reptiles to 20 (fishes times (in comparison to mammals or even 45 (reptiles to 100 (fishes times (in comparison to birds lower than in endotherms. While on average all taxa were clearly separated from each other, individual growth rates overlapped between several taxa and even between endotherms and ectotherms. Dinosaurs had growth rates intermediate between similar sized/scaled-up reptiles and mammals, but a much lower rate than scaled-up birds. All dinosaurian growth rates were within the range of extant reptiles and mammals, and were lower than those of birds. Under the assumption that growth rate and metabolic rate are indeed linked, our results suggest two alternative interpretations. Compared to other sauropsids, the growth rates of studied dinosaurs clearly indicate that they had an ectothermic rather than an endothermic metabolic rate. Compared to other vertebrate growth rates, the overall high variability in growth rates of extant groups and the high overlap between individual growth rates of endothermic and ectothermic extant species make it impossible to rule

Radon and thoron emanation measurements and the effect of ground water

International Nuclear Information System (INIS)

Carriveau, G.W.; Harbottle, G.

1980-01-01

In the past, corrections for annual dose rate calculations have used a qualitative approach to the effect of ground water saturation and radon and thoron loss. An example is presented of how this correction can now be precisely determined using natural gamma-ray activities to determine the amount of emanation from ceramic sherds and soil, both in a dry state and saturated with ground water. The experimental data also provide information concerning disequilibria in 234 Th and 226 Ra regions of the decay series. Additionally, approximate values of uranium and thorium concentrations (sufficiently accurate for authenticity work) are provided

Study of the emanation levels of 222Rn present in Naturally Occurring Radioactive Materials - NORM

International Nuclear Information System (INIS)

Miranda, Marcia Valeria de Fatima da Encarnacao Sa

2009-01-01

The presence of Naturally Occurring Radioactive Material (NORM), contaminating oil and gas facilities, is a common fact in the petroleum industry, and can be severe enough to expose the workers to elevated levels of radiation. Thus, contaminated residues need to be segregated but, this is still a problem without a satisfactory solution. Currently, the most practical and economic option for discarding this material is to stock it in areas of the facility whose access is controlled. Certain equipment used in the petroleum industry has scale and sludge that could be associated to important levels of radioactivity. Typically, the scale is a mixture of carbonate and sulphate minerals, such as barite (BaSO 4 ), that easily incorporates 226 Ra and 228 Ra in its structures. The objective of this work was to measure the emanations of the radon present in these NORM samples, via diffusion chambers containing a nuclear track detector (CR-39). The images of particle alpha tracks emanated by 222 Rn registered on CR-39 were observed with a Nikon E400 optic microscope and captured by a Nikon Coolpix digital camera and then stored in a database, to later count the tracks using the computational program, Image Pro plus. Being that the emanation rate of 222 Rn was proportional to the number of these tracks the methodology permitted the comparison of contamination levels of the analyzed samples. (author)

5 CFR 9901.312 - Maximum rates of base salary and adjusted salary.

Science.gov (United States)

2010-01-01

... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Maximum rates of base salary and adjusted salary. 9901.312 Section 9901.312 Administrative Personnel DEPARTMENT OF DEFENSE HUMAN RESOURCES....312 Maximum rates of base salary and adjusted salary. (a) Subject to § 9901.105, the Secretary may...

Field fluxes and speciation of arsines emanating from soils.

Science.gov (United States)

Mestrot, Adrien; Feldmann, Joerg; Krupp, Eva M; Hossain, Mahmud S; Roman-Ross, Gabriela; Meharg, Andrew A

2011-03-01

The biogeochemical cycle of arsenic (As) has been extensively studied over the past decades because As is an environmentally ubiquitous, nonthreshold carcinogen, which is often elevated in drinking water and food. It has been known for over a century that micro-organisms can volatilize inorganic As salts to arsines (arsine AsH(3), mono-, di-, and trimethylarsines, MeAsH(2), Me(2)AsH, and TMAs, respectively), but this part of the As cycle, with the exception of geothermal environs, has been almost entirely neglected because of a lack of suited field measurement approaches. Here, a validated, robust, and low-level field-deployable method employing arsine chemotrapping was used to quantify and qualify arsines emanating from soil surfaces in the field. Up to 240 mg/ha/y arsines was released from low-level polluted paddy soils (11.3 ± 0.9 mg/kg As), primarily as TMAs, whereas arsine flux below method detection limit was measured from a highly contaminated mine spoil (1359 ± 212 mg/kg As), indicating that soil chemistry is vital in understanding this phenomenon. In microcosm studies, we could show that under reducing conditions, induced by organic matter (OM) amendment, a range of soils varied in their properties, from natural upland peats to highly impacted mine-spoils, could all volatilize arsines. Volatilization rates from 0.5 to 70 μg/kg/y were measured, and AsH(3), MeAsH(2), Me(2)AsH, and TMAs were all identified. Addition of methylated oxidated pentavalent As, namely monomethylarsonic acid (MMAA) and dimethylarsinic acid (DMAA), to soil resulted in elevated yearly rates of volatilization with up to 3.5% of the total As volatilized, suggesting that the initial conversion of inorganic As to MMAA limits the rate of arsine and methylarsines production by soils. The nature of OM amendment altered volatilization quantitatively and qualitatively, and total arsines release from soil showed correlation between the quantity of As and the concentration of dissolved organic

The scaling of maximum and basal metabolic rates of mammals and birds

Science.gov (United States)

Barbosa, Lauro A.; Garcia, Guilherme J. M.; da Silva, Jafferson K. L.

2006-01-01

Allometric scaling is one of the most pervasive laws in biology. Its origin, however, is still a matter of dispute. Recent studies have established that maximum metabolic rate scales with an exponent larger than that found for basal metabolism. This unpredicted result sets a challenge that can decide which of the concurrent hypotheses is the correct theory. Here, we show that both scaling laws can be deduced from a single network model. Besides the 3/4-law for basal metabolism, the model predicts that maximum metabolic rate scales as M, maximum heart rate as M, and muscular capillary density as M, in agreement with data.

Rate maximum calculation of Dpa in CNA-II pressure vessel

International Nuclear Information System (INIS)

Mascitti, J. A

2012-01-01

The maximum dpa rate was calculated for the reactor in the following state: fresh fuel, no Xenon, a Boron concentration of 15.3 ppm, critical state, its control rods in the criticality position, hot, at full power (2160 MW). It was determined that the maximum dpa rate under such conditions is 3.54(2)x10 12 s -1 and it is located in the positions corresponding to θ=210 o in the azimuthal direction, and z=20 cm and -60 cm respectively in the axial direction, considering the calculation mesh centered at half height of the fuel element (FE) active length. The dpa rate spectrum was determined as well as the contribution to it for 4 energy groups: a thermal group, two epithermal groups and a fast one. The maximum dpa rate considering the photo-neutrons production from (γ, n) reaction in the heavy water of coolant and moderator was 3.93(4)x10 12 s -1 that is 11% greater than the obtained without photo-neutrons. This verified significant difference between both cases, suggest that photo-neutrons in large heavy water reactors such as CNA-II should not be ignored. The maximum DPA rate in the first mm of the reactor pressure vessel was calculated too and it was obtained a value of 4.22(6)x10 12 s -1 . It should be added that the calculation was carried out with the reactor complete accurate model, with no approximations in spatial or energy variables. Each value has, between parentheses, a percentage relative error representing the statistical uncertainty due to the probabilistic Monte Carlo method used to estimate it. More representative values may be obtained with this method if equilibrium burn-up distribution is used (author)

Emanation thermal analysis of SiC based materials

Czech Academy of Sciences Publication Activity Database

Bálek, V.; Zeleňák, V.; Mitsuhashi, T.; Bakardjieva, Snejana; Šubrt, Jan; Haneda, H.

2002-01-01

Roč. 67, č. 1 (2002), s. 83-89 ISSN 1418-2874 R&D Projects: GA MŠk ME 180 Grant - others:EFDA(XE) TTMA-001 Institutional research plan: CEZ:AV0Z4032918 Keywords : emanation thermal analysis * SEM * SiC nanocomposites Subject RIV: CA - Inorganic Chemistry Impact factor: 0.598, year: 2002

Exercise-induced maximum metabolic rate scaled to body mass by ...

African Journals Online (AJOL)

user

2016-10-27

Oct 27, 2016 ... maximum aerobic metabolic rate (MMR) is proportional to the fractal extent ... metabolic rate with body mass can be obtained by taking body .... blood takes place. ..... MMR and BMR is that MMR is owing mainly to respiration in skeletal .... the spectra of surface area scaling strategies of cells and organisms:.

Stress-intensity factors for cracks emanating from the loaded fastener hole

Science.gov (United States)

Shivakumar, V.; Hsu, Y. C.

1977-01-01

Using a series approach and the Muskhelishvili formulation in the two-dimensional theory of elasticity, stress-intensity factors K are derived for problems in which cracks emanate radially from the boundary of an arbitrarily loaded internal circular hole in an infinite plate. Numerical values are obtained for K(I) and K(II) for radial cracks from a hole containing a loose-fitted pin or rivet that is pulled perpendicular to the crack direction in the plane of the plate. The method is a general one for determining K for a set of symmetrically emanating radial cracks for a variety of concentrated or distributed tractions on the circular hole.

Emanation thermal analysis. Principle of the method, preparation of samples and apparatus

International Nuclear Information System (INIS)

Balek, V.; Pentinghaus, H.J.

1993-12-01

Principles of the title method are outlined and the sample preparation procedures and instrumental designs are described. The publication is divided into chapters as follows: (I) Introduction; (II) Sample labelling: (II.1) Introducing parent nuclides as a source of inert gas in solid; Distribution of inert gas in the sample; (II.2) Introducing inert gases without parent nuclides (using the recoil effect of nuclear reactions and using ion bombardment); (II.3) Choice of the suitable labelling technique; (III) Equipment for emanation thermal analysis: (III.1) Inert gas detection and measurement of inert gas release rate; (III.2) System of carrier gas flow and stabilization; (IV) Determination of the optimal conditions for radon release rate measurement; (V) Example of ETA measurement. (P.A.). 1 tab., 10 figs. 5 refs

Radon emanation and soil moisture effects on airborne gamma-ray measurements

International Nuclear Information System (INIS)

Grasty, R.L.

1997-01-01

A theoretical model is developed to explain variations in airborne gamma-ray measurements over a calibration range near Ottawa, Ontario. The gamma-ray flux from potassium and the thorium decay series showed an expected decrease with increasing soil moisture. However, the gamma-ray flux from the uranium decay series was highest in the spring when the ground was water-saturated and even covered with snow. These results are explained through the build-up of radon and its associated gamma-ray-emitting decay products in the clay soil of the calibration range with increasing soil moisture. Similar results were found from airborne measurements over other clay soils. However, measurements over sandy soils showed that the count rates from all three radio elements increased with decreasing soil moisture. This difference between soil types was attributed to the lower radon emanation of the more coarse-grained sandy soils compared to finer-grained clay soils. The theoretical and experimental results demonstrate that any estimate of the natural gamma-ray field caused by radium in the ground must take into consideration the radon emanation coefficient of the soil. The radon diffusion coefficient of the soil must also be considered since it depends strongly on soil moisture. This has significant implications for the assessment of outdoor radiation doses using laboratory analyses of soil samples and the use of ground and airborne gamma-ray measurements for radon potential mapping

Discharge of water containing waste emanating from land to the ...

African Journals Online (AJOL)

containing waste (wastewater), which emanates from land-based sources and which directly impact on the marine environment. These sources include sea outfalls, storm water drains, canals, rivers and diffuse sources of pollution. To date ...

Estimation of maximum credible atmospheric radioactivity concentrations and dose rates from nuclear tests

International Nuclear Information System (INIS)

Telegadas, K.

1979-01-01

A simple technique is presented for estimating maximum credible gross beta air concentrations from nuclear detonations in the atmosphere, based on aircraft sampling of radioactivity following each Chinese nuclear test from 1964 to 1976. The calculated concentration is a function of the total yield and fission yield, initial vertical radioactivity distribution, time after detonation, and rate of horizontal spread of the debris with time. calculated maximum credible concentrations are compared with the highest concentrations measured during aircraft sampling. The technique provides a reasonable estimate of maximum air concentrations from 1 to 10 days after a detonation. An estimate of the whole-body external gamma dose rate corresponding to the maximum credible gross beta concentration is also given. (author)

Calculation of radon emanation from a radiferous pile

International Nuclear Information System (INIS)

Zettwoog, Pierre.

1980-07-01

The theory of unidimensional diffusion of radon in a porous medium, either radiferous or not, is presented taking into account the effects of humidity and the adsorption of radon on the medium. Experimental procedures for determining the two main characteristics of diffusion in a medium, the relaxation length of the diffusion of radon and the emanating power, are described [fr

Maximum production rate optimization for sulphuric acid decomposition process in tubular plug-flow reactor

International Nuclear Information System (INIS)

Wang, Chao; Chen, Lingen; Xia, Shaojun; Sun, Fengrui

2016-01-01

A sulphuric acid decomposition process in a tubular plug-flow reactor with fixed inlet flow rate and completely controllable exterior wall temperature profile and reactants pressure profile is studied in this paper by using finite-time thermodynamics. The maximum production rate of the aimed product SO 2 and the optimal exterior wall temperature profile and reactants pressure profile are obtained by using nonlinear programming method. Then the optimal reactor with the maximum production rate is compared with the reference reactor with linear exterior wall temperature profile and the optimal reactor with minimum entropy generation rate. The result shows that the production rate of SO 2 of optimal reactor with the maximum production rate has an increase of more than 7%. The optimization of temperature profile has little influence on the production rate while the optimization of reactants pressure profile can significantly increase the production rate. The results obtained may provide some guidelines for the design of real tubular reactors. - Highlights: • Sulphuric acid decomposition process in tubular plug-flow reactor is studied. • Fixed inlet flow rate and controllable temperature and pressure profiles are set. • Maximum production rate of aimed product SO 2 is obtained. • Corresponding optimal temperature and pressure profiles are derived. • Production rate of SO 2 of optimal reactor increases by 7%.

Theoretical aspects of the Semkow fractal model in the radon emanation in solids

International Nuclear Information System (INIS)

Cruz G, H.S.

1997-01-01

The basic elements of the Fractals theory are developed. The physical basis of radon emission in solids are described briefly. It is obtained that the emanation power E R of mineral grains is scaled as r 0 D-3 (r 0 : grain radius). From a logarithmic graph E R versus grain size is deduced the fractal dimension of the emanation surface. The experimental data of different materials give an interval in the fractal dimension D between 2.1 and 2.8 (Author)

Maximum discharge rate of liquid-vapor mixtures from vessels

International Nuclear Information System (INIS)

Moody, F.J.

1975-09-01

A discrepancy exists in theoretical predictions of the two-phase equilibrium discharge rate from pipes attached to vessels. Theory which predicts critical flow data in terms of pipe exit pressure and quality severely overpredicts flow rates in terms of vessel fluid properties. This study shows that the discrepancy is explained by the flow pattern. Due to decompression and flashing as fluid accelerates into the pipe entrance, the maximum discharge rate from a vessel is limited by choking of a homogeneous bubbly mixture. The mixture tends toward a slip flow pattern as it travels through the pipe, finally reaching a different choked condition at the pipe exit

Impulsive radon emanation on a creeping segment of the San Andreas fault, California

International Nuclear Information System (INIS)

King, C.-Y.

1984-01-01

Radon emanation was continuously monitored for several months at two locations along a creeping segment of the San Andreas fault in central California. The recorded emanations showed several impulsive increases that lasted as much as five hours with amplitudes considerably larger than meteorologically induced diurnal variations. Some of the radon increases were accompanied or followed by earthquakes or fault-creep events. They were possibly the result of some sudden outbursts of relatively radon-rich ground gas, sometimes triggered by crustal deformation or vibration. (Auth.)

Intercomparison of radon emanation in Moroccan and Tunisian phosphate rocks

International Nuclear Information System (INIS)

Khalil, A.; Membrey, F.; Klein, D.; Chambaudet, A.; Iraqui, R.

1992-01-01

We suggest a method for measuring the emanation of radon gas of phosphates mineral from different origins using solid state track nuclear detectors (CR39 and LR115) with the aim to determinate radioactivity effects on the human. (author)

Use of Emanation Thermal Analysis in the characterization of nuclear waste forms and their alteration products

International Nuclear Information System (INIS)

Balek, V; Malek, Z.; Banba, T.; Mitamura, H.; Vance, E.R.

1999-01-01

Emanation Thermal Analysis (ETA) was used for the characterization of thermal behavior of two nuclear waste glasses, basalt volcanic glass and perovskite ceramics before and after hydrolytic treatment. The release of radon, formed by the spontaneous α-decay of 228 Th and 224 Ra and incorporated into samples to a maximum depth of 100 nm from the surface due to the recoil, was measured during heating of the samples from 20 to 1200degC and subsequent cooling. Temperatures of the annealing of surface roughness, micro-cracks and other defects, produced by manufacture and/or by subsequent treatment of glass and ceramic samples, were determined using the ETA. Microstructure changes of glass corrosion accompanying their dehydration and thermal decomposition were characterized by the radon release rate changes. The effect of hydrolytic alteration on the thermal behavior of the nuclear waste glass was revealed by ETA in an early corrosion stage. In the alteration product of the perovskite ceramics the diffusion mobility of radon was assessed in the temperature range 1000-1200degC. The thermal stability of radiation-induced defects in perovskite ceramic powder bombarded by He + ions to doses of 10 14 and 10 16 ions/cm 2 was determined by means of ETA. (author)

On the equivalence between the minimum entropy generation rate and the maximum conversion rate for a reactive system

International Nuclear Information System (INIS)

Bispo, Heleno; Silva, Nilton; Brito, Romildo; Manzi, João

2013-01-01

Highlights: • Minimum entropy generation (MEG) principle improved the reaction performance. • MEG rate and the maximum conversion equivalence have been analyzed. • Temperature and residence time are used to the domain establishment of MEG. • Satisfying the temperature and residence time relationship results a optimal performance. - Abstract: The analysis of the equivalence between the minimum entropy generation (MEG) rate and the maximum conversion rate for a reactive system is the main purpose of this paper. While being used as a strategy of optimization, the minimum entropy production was applied to the production of propylene glycol in a Continuous Stirred-Tank Reactor (CSTR) with a view to determining the best operating conditions, and under such conditions, a high conversion rate was found. The effects of the key variables and restrictions on the validity domain of MEG were investigated, which raises issues that are included within a broad discussion. The results from simulations indicate that from the chemical reaction standpoint a maximum conversion rate can be considered as equivalent to MEG. Such a result can be clearly explained by examining the classical Maxwell–Boltzmann distribution, where the molecules of the reactive system under the condition of the MEG rate present a distribution of energy with reduced dispersion resulting in a better quality of collision between molecules with a higher conversion rate

Newton's Metaphysics of Space as God's Emanative Effect

Science.gov (United States)

Jacquette, Dale

2014-09-01

In several of his writings, Isaac Newton proposed that physical space is God's "emanative effect" or "sensorium," revealing something interesting about the metaphysics underlying his mathematical physics. Newton's conjectures depart from Plato and Aristotle's metaphysics of space and from classical and Cambridge Neoplatonism. Present-day philosophical concepts of supervenience clarify Newton's ideas about space and offer a portrait of Newton not only as a mathematical physicist but an independent-minded rationalist philosopher.

Fumigant dosages below maximum label rate control some soilborne pathogens

Directory of Open Access Journals (Sweden)

Shachaf Triky-Dotan

2016-08-01

Full Text Available The activity of commercial soil fumigants on some key soilborne pathogens was assessed in sandy loam soil under controlled conditions. Seven soil fumigants that are registered in California or are being or have been considered for registration were used in this study: dimethyl disulfide (DMDS mixed with chloropicrin (Pic (79% DMDS and 21% Pic, Tri-Con (50% methyl bromide and 50% Pic, Midas Gold (33% methyl iodide [MI] and 67% Pic, Midas Bronze (50% MI and 50% Pic, Midas (MI, active ingredient [a.i.] 97.8%, Pic (a.i. 99% trichloronitromethane and Pic-Clor 60 (57% Pic and 37% 1,3-dichloropropene [1–3,D]. Dose-response models were calculated for pathogen mortality after 24 hours of exposure to fumigants. Overall, the tested fumigants achieved good efficacy with dosages below the maximum label rate against the tested pathogens. In this study, Pythium ultimum and citrus nematode were sensitive to all the fumigants and Verticillium dahliae was resistant. For most fumigants, California regulations restrict application rates to less than the maximum (federal label rate, meaning that it is possible that the fumigants may not control major plant pathogens. This research provides information on the effectiveness of these alternatives at these lower application rates. The results from this study will help growers optimize application rates for registered fumigants (such as Pic and 1,3-D and will help accelerate the adoption of new fumigants (such as DMDS if they are registered in California.

Interim report to the Northern Ecosystem Initiative from the Northern Ecological Monitoring and Assessment Network (EMAN-North)

International Nuclear Information System (INIS)

Wakelyn, L.; Eamer, J.

2001-01-01

The Northern Ecological Monitoring and Assessment Network (EMAN-North) has received funding for a proposal submitted to the Northern Ecosystems Initiative (NEI) in January 2001. EMAN-North is a network that coordinates ecological monitoring in northern Canada. Its geographic scope comprises 40 per cent of the geographic area of Canada, including Yukon, Northwest Territories and Nunavut, and an area near Churchill, Manitoba. Funding was awarded because the proposed EMAN-North project addressed the NEI priority of Monitoring Ecosystem Status and Trends, and Ecosystem Impacts of Climate Change. The project was also aimed at improving the network's capacity for long-term ecological monitoring, assessment and reporting. Several activities deal specifically with ecological impacts of climate change. This paper described the need and the context for ecological monitoring in northern Canada and defined a strategic direction for EMAN-North. The project will include many individuals involved in ecological monitoring in the north to deliver information on ecosystem changes to decision-makers and the public. refs., tabs., figs

Emanation-thermal characteristics of Ba-salts of some aromatic acids in the temperature range between 298 and 373 K

Energy Technology Data Exchange (ETDEWEB)

Balek, V; Prachar, M [Ustav Jaderneho Vyzkumu, Rez (Czechoslovakia); Kroupa, J [Vyzkumny Ustav Syntetickych Pryskyric a Laku, Pardubice (Czechoslovakia)

1977-01-01

The paper presents the emanation-thermal characteristics of Ba salts of some monocarboxylic acids (phtalic, isophtalic and terephtalic) and dicarboxylic acids (benzoic, salicylic, 1,4-aminobenzoic, 1,2-Cl-benzoic and 1,2-I-benzoic). It is shown that the emanation thermal characteristics measured in the temperature range between 298 and 373 K are suitable for estimating diffusion properties of studied organic solids. An apparatus for determining emanation-thermal characteristics is proposed.

Study of variations of radon emanations from soil in Morocco using solid state nuclear track detectors. Correlations with atmospheric parameters and seismic activities

International Nuclear Information System (INIS)

Boukhal, H.

1993-01-01

This study investigates the quantity variations of radon emanating from soil in accordance with time. It aims to verify the possibility of the radon sign use in earthquake prediction. Regular measures of radon concentration in soil have been carried out over the two years 1991 and 1992 in five towns of Morocco: Rabat, Tetouan, Ifrane and Khouribga, and in geophysic observatory of Ibn Rochd (Berchid region). The measuring method is based on the solid state nuclear track detectors technique. The obtained results have shown an influence of the atmospheric effects on the radon emanation. The experiment proved that, on one hand, the variations of the aforesaid influence are correlated to variations of the pluviometry and the atmospheric temperature and, on the other hand, there is no notable effect of atmospheric pressure or atmospheric humidity. The good correlations between the different seismic activities and the variations of radon emanation rate in the five measurement stations, have shown the interest of radon use in the earthquake prediction field. 81 refs., 100 figs., 17 tabs.(F. M.)

[The maximum heart rate in the exercise test: the 220-age formula or Sheffield's table?].

Science.gov (United States)

Mesquita, A; Trabulo, M; Mendes, M; Viana, J F; Seabra-Gomes, R

1996-02-01

To determine in the maximum cardiac rate in exercise test of apparently healthy individuals may be more properly estimated through 220-age formula (Astrand) or the Sheffield table. Retrospective analysis of clinical history and exercises test of apparently healthy individuals submitted to cardiac check-up. Sequential sampling of 170 healthy individuals submitted to cardiac check-up between April 1988 and September 1992. Comparison of maximum cardiac rate of individuals studied by the protocols of Bruce and modified Bruce, in interrupted exercise test by fatigue, and with the estimated values by the formulae: 220-age versus Sheffield table. The maximum cardiac heart rate is similar with both protocols. This parameter in normal individuals is better predicted by the 220-age formula. The theoretic maximum cardiac heart rate determined by 220-age formula should be recommended for a healthy, and for this reason the Sheffield table has been excluded from our clinical practice.

Fast maximum likelihood estimation of mutation rates using a birth-death process.

Science.gov (United States)

Wu, Xiaowei; Zhu, Hongxiao

2015-02-07

Since fluctuation analysis was first introduced by Luria and Delbrück in 1943, it has been widely used to make inference about spontaneous mutation rates in cultured cells. Under certain model assumptions, the probability distribution of the number of mutants that appear in a fluctuation experiment can be derived explicitly, which provides the basis of mutation rate estimation. It has been shown that, among various existing estimators, the maximum likelihood estimator usually demonstrates some desirable properties such as consistency and lower mean squared error. However, its application in real experimental data is often hindered by slow computation of likelihood due to the recursive form of the mutant-count distribution. We propose a fast maximum likelihood estimator of mutation rates, MLE-BD, based on a birth-death process model with non-differential growth assumption. Simulation studies demonstrate that, compared with the conventional maximum likelihood estimator derived from the Luria-Delbrück distribution, MLE-BD achieves substantial improvement on computational speed and is applicable to arbitrarily large number of mutants. In addition, it still retains good accuracy on point estimation. Published by Elsevier Ltd.

Modelization of the radon emanation from natural sources in the soil

International Nuclear Information System (INIS)

Sabir, A.; Marah, H.; Hlou, L.; Klein, D.; Chambaudet, A.

1996-01-01

To evaluate the radon emanation and hence the risk to populations, we have adapted an original mathematical model based on the method of distribute parcels (L. Hlou, These d'etat, Faculte des Sciences, Kenitra, MAROC, 1994). This allows us to follow the migration, in time and space, of a quantity of radon produced in a unit volume as a function of the geological, morphological and structural characteristics of the site studied. Knowing the petrographic and pedologic parameters enables us to calculate the radon concentration in all points inside the soil of the site as well as the radon emanation in the atmosphere. It is therefore possible to calculate the radiological risk for populations brought to live on the site studied. Different applications of this model have been realised in Morocco and in France to demonstrate its efficiency. (author)

13 CFR 107.845 - Maximum rate of amortization on Loans and Debt Securities.

Science.gov (United States)

2010-01-01

... ADMINISTRATION SMALL BUSINESS INVESTMENT COMPANIES Financing of Small Businesses by Licensees Structuring Licensee's Financing of An Eligible Small Business: Terms and Conditions of Financing § 107.845 Maximum... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Maximum rate of amortization on...

Measurement of 222Rn flux, 222Rn emanation and 226Ra concentration from injection well pipe scale

International Nuclear Information System (INIS)

Rood, A.S.; Kendrick, D.T.

1996-01-01

The presence of Naturally Occurring Radioactive Material (NORM) has been recognized since the early 1930s in petroleum reservoirs and in oil and gas production and processing facilities. NORM was typically observed in barite scale that accumulated on the interior of oil production tubing and in storage tank and heater-treater separation sludge. Recent concern has been expressed over the health impacts from the uncontrolled release of NORM to the public. There are several potential exposure pathways to humans from oil-field NORM. Among these is inhalation of radon gas and its daughter products. For this exposure pathway to be of any significance, radon must first be released from the NORM matrix and diffuse in free air. The radon emanation fraction refers to the fraction of radon atoms produced by the decay of radium, that migrate from the bulk material as free gaseous atoms. The purpose of this investigation was to characterize the radon release rates from NORM-scale contaminated production tubing being stored above ground, characterize the radon emanation fraction of the bulk scale material when removed from the tubing, and characterize the radium concentrations of the scale. Accurate characterization of 222 Rn emanation fractions from pipe scale may dictate the type of disposal options available for this waste. Characterization of radon release from stored pipes will assist in determining if controls are needed for workers or members of the public downwind from the source. Due to the sensitive nature of this data, the location of this facility is not disclosed

Structural, morphological and mechanical properties of niobium nitride thin films grown by ion and electron beams emanated from plasma

Science.gov (United States)

Siddiqui, Jamil; Hussain, Tousif; Ahmad, Riaz; Umar, Zeeshan A.; Abdus Samad, Ubair

2016-05-01

The influence of variation in plasma deposition parameters on the structural, morphological and mechanical characteristics of the niobium nitride films grown by plasma-emanated ion and electron beams are investigated. Crystallographic investigation made by X-ray diffractometer shows that the film synthesized at 10 cm axial distance with 15 plasma focus shots (PFS) exhibits better crystallinity when compared to the other deposition conditions. Morphological analysis made by scanning electron microscope reveals a definite granular pattern composed of homogeneously distributed nano-spheroids grown as clustered particles for the film synthesized at 10 cm axial distance for 15 PFS. Roughness analysis demonstrates higher rms roughness for the films synthesized at shorter axial distance and by greater number of PFS. Maximum niobium atomic percentage (35.8) and maximum average hardness (19.4 ± 0.4 GPa) characterized by energy-dispersive spectroscopy and nano-hardness analyzer respectively are observed for film synthesized at 10 cm axial distance with 15 PFS.

Radium-226 content and emanating power of some timepieces manufactured in the years 1926--1951

International Nuclear Information System (INIS)

Keane, A.T.; Huff, D.R.

Thirty-two radium-dial timepieces manufactured in the years 1926 to 1951 by a company in Connecticut were individually sealed in small steel cans for determination of radium-C ( 214 Bi) activity by γ-ray spectroscopy. Each can was counted within a few hours after sealing and again 5 or 6 days later; from the two observations, radium-C activities at time of sealing (nonemanating radium content) and at equilibrium (total radium content) were calculated. The mean radium-226 content of 22 pocket watches was 348 nCi (range, 159 to 606), and the mean emanating power (1-nonemanating Ra/total Ra) was 0.175 (range, 0.09 to 0.33). The mean radium-226 content of 9 wrist watches was 150 nCi (range, 54 to 449), and the mean emanating power was 0.242 (range, 0.12 to 0.34). The radium-226 content of the one small clock was 633 nCi, and its emanating power was 0.15. The concentration of radon-222 in the air of a sealed room of dimensions 3 x 3 x 3 m would be increased by about 3 pCi/l if a watch containing 400 nCi of radium-226 with an emanating power of 0.2 were left in the room for a few weeks. (U.S.)

Methodological aspects of crossover and maximum fat-oxidation rate point determination.

Science.gov (United States)

Michallet, A-S; Tonini, J; Regnier, J; Guinot, M; Favre-Juvin, A; Bricout, V; Halimi, S; Wuyam, B; Flore, P

2008-11-01

Indirect calorimetry during exercise provides two metabolic indices of substrate oxidation balance: the crossover point (COP) and maximum fat oxidation rate (LIPOXmax). We aimed to study the effects of the analytical device, protocol type and ventilatory response on variability of these indices, and the relationship with lactate and ventilation thresholds. After maximum exercise testing, 14 relatively fit subjects (aged 32+/-10 years; nine men, five women) performed three submaximum graded tests: one was based on a theoretical maximum power (tMAP) reference; and two were based on the true maximum aerobic power (MAP). Gas exchange was measured concomitantly using a Douglas bag (D) and an ergospirometer (E). All metabolic indices were interpretable only when obtained by the D reference method and MAP protocol. Bland and Altman analysis showed overestimation of both indices with E versus D. Despite no mean differences between COP and LIPOXmax whether tMAP or MAP was used, the individual data clearly showed disagreement between the two protocols. Ventilation explained 10-16% of the metabolic index variations. COP was correlated with ventilation (r=0.96, P<0.01) and the rate of increase in blood lactate (r=0.79, P<0.01), and LIPOXmax correlated with the ventilation threshold (r=0.95, P<0.01). This study shows that, in fit healthy subjects, the analytical device, reference used to build the protocol and ventilation responses affect metabolic indices. In this population, and particularly to obtain interpretable metabolic indices, we recommend a protocol based on the true MAP or one adapted to include the transition from fat to carbohydrate. The correlation between metabolic indices and lactate/ventilation thresholds suggests that shorter, classical maximum progressive exercise testing may be an alternative means of estimating these indices in relatively fit subjects. However, this needs to be confirmed in patients who have metabolic defects.

Transport properties and microstructure changes of talc characterized by emanation

Czech Academy of Sciences Publication Activity Database

Pérez-Maqueda, L. A.; Balek, Vladimír; Poyato, J.; Šubrt, Jan; Beneš, M.; Ramírez-Valle, V.; Buntseva, I.M.; Beckman, I. N.; Pérez-Rodríguez, J. L.

2008-01-01

Roč. 92, č. 1 (2008), s. 253-258 ISSN 1388-6150 R&D Projects: GA MŠk LC523 Grant - others:MST(ES) MAT 2005-04838 Institutional research plan: CEZ:AV0Z40320502 Keywords : DTA emanation thermal analysis * microstructure changes * radon diffusion Subject RIV: CA - Inorganic Chemistry Impact factor: 1.630, year: 2008

Disentangling the effects of alternation rate and maximum run length on judgments of randomness

Directory of Open Access Journals (Sweden)

Sabine G. Scholl

2011-08-01

Full Text Available Binary sequences are characterized by various features. Two of these characteristics---alternation rate and run length---have repeatedly been shown to influence judgments of randomness. The two characteristics, however, have usually been investigated separately, without controlling for the other feature. Because the two features are correlated but not identical, it seems critical to analyze their unique impact, as well as their interaction, so as to understand more clearly what influences judgments of randomness. To this end, two experiments on the perception of binary sequences orthogonally manipulated alternation rate and maximum run length (i.e., length of the longest run within the sequence. Results show that alternation rate consistently exerts a unique effect on judgments of randomness, but that the effect of alternation rate is contingent on the length of the longest run within the sequence. The effect of maximum run length was found to be small and less consistent. Together, these findings extend prior randomness research by integrating literature from the realms of perception, categorization, and prediction, as well as by showing the unique and joint effects of alternation rate and maximum run length on judgments of randomness.

19 CFR 212.07 - Rulemaking on maximum rates for attorney fees.

Science.gov (United States)

2010-04-01

... 19 Customs Duties 3 2010-04-01 2010-04-01 false Rulemaking on maximum rates for attorney fees. 212.07 Section 212.07 Customs Duties UNITED STATES INTERNATIONAL TRADE COMMISSION INVESTIGATIONS OF UNFAIR PRACTICES IN IMPORT TRADE IMPLEMENTATION OF THE EQUAL ACCESS TO JUSTICE ACT General Provisions...

Use of emanation thermal analysis in the microstructure diagnostics of aluminia coatings

Czech Academy of Sciences Publication Activity Database

Balek, V.; Beneš, M.; Šubrt, Jan

2008-01-01

Roč. 52, č. 2 (2008), s. 85-89 ISSN 0862-5468 Institutional research plan: CEZ:AV0Z40320502 Keywords : aluminia coatings * emanation thermal analysis * SEM Subject RIV: CA - Inorganic Chemistry Impact factor: 0.644, year: 2008

Connection between radon emanation and some structural properties of coal-slag as building material

International Nuclear Information System (INIS)

Somlai, J.; Jobbagy, V.; Somlai, K.; Kovacs, J.; Nemeth, Cs.; Kovacs, T.

2008-01-01

Radionuclides of natural origin may accumulate in different industrial waste materials and by-products. The use of coal bottom ash or coal-slag as building material in Hungary is widespread. Because of the elevated radium content of coal-slag, high radon concentration has been detected in buildings containing coal-slag as building material. In two towns, where buildings contain coal-slag with almost the same radium concentration, the indoor radon concentrations have been found to differ significantly. In order to investigate the cause of the difference in the emanation coefficients, slag samples from the two locations were examined for grain-size distribution, density, pore volume, and specific surface. The applied methods were: gamma spectrometry for the radium concentration of the samples; Lucas cell method for the radon emanation; nitrogen absorption-desorption isotherms analyzed using the BET theory and mercury poremeter for the specific surface and pore volume. It was found that the great difference in the emanation coefficients (1.35±0.13% and 14.3±0.92%) of the coal-slag samples is primarily influenced by the pore volume and the specific surface

Low reproducibility of maximum urinary flow rate determined by portable flowmetry

NARCIS (Netherlands)

Sonke, G. S.; Kiemeney, L. A.; Verbeek, A. L.; Kortmann, B. B.; Debruyne, F. M.; de la Rosette, J. J.

1999-01-01

To evaluate the reproducibility in maximum urinary flow rate (Qmax) in men with lower urinary tract symptoms (LUTSs) and to determine the number of flows needed to obtain a specified reliability in mean Qmax, 212 patients with LUTSs (mean age, 62 years) referred to the University Hospital Nijmegen,

Maximum inflation of the type 1 error rate when sample size and allocation rate are adapted in a pre-planned interim look.

Science.gov (United States)

Graf, Alexandra C; Bauer, Peter

2011-06-30

We calculate the maximum type 1 error rate of the pre-planned conventional fixed sample size test for comparing the means of independent normal distributions (with common known variance) which can be yielded when sample size and allocation rate to the treatment arms can be modified in an interim analysis. Thereby it is assumed that the experimenter fully exploits knowledge of the unblinded interim estimates of the treatment effects in order to maximize the conditional type 1 error rate. The 'worst-case' strategies require knowledge of the unknown common treatment effect under the null hypothesis. Although this is a rather hypothetical scenario it may be approached in practice when using a standard control treatment for which precise estimates are available from historical data. The maximum inflation of the type 1 error rate is substantially larger than derived by Proschan and Hunsberger (Biometrics 1995; 51:1315-1324) for design modifications applying balanced samples before and after the interim analysis. Corresponding upper limits for the maximum type 1 error rate are calculated for a number of situations arising from practical considerations (e.g. restricting the maximum sample size, not allowing sample size to decrease, allowing only increase in the sample size in the experimental treatment). The application is discussed for a motivating example. Copyright © 2011 John Wiley & Sons, Ltd.

Radon exhalation of cementitious materials made with coal fly ash: Part 1 - scientific background and testing of the cement and fly ash emanation

International Nuclear Information System (INIS)

Kovler, K.; Perevalov, A.; Steiner, V.; Metzger, L.A.

2005-01-01

Increased interest in measuring radionuclides and radon concentrations in fly ash, cement and other components of building products is due to the concern of health hazards of naturally occurring radioactive materials (NORM). The current work focuses on studying the influence of fly ash (FA) on radon-exhalation rate (radon flux) from cementitious materials. The tests were carried out on cement paste specimens with different FA contents. The first part of the paper presents the scientific background and describes the experiments, which we designed for testing the radon emanation of the raw materials used in the preparation of the cement-FA pastes. It is found that despite the higher 226 Ra content in FA (more than 3 times, compared with Portland cement) the radon emanation is significantly lower in FA (7.65% for cement vs. 0.52% only for FA)

Conifers in cold environments synchronize maximum growth rate of tree-ring formation with day length.

Science.gov (United States)

Rossi, Sergio; Deslauriers, Annie; Anfodillo, Tommaso; Morin, Hubert; Saracino, Antonio; Motta, Renzo; Borghetti, Marco

2006-01-01

Intra-annual radial growth rates and durations in trees are reported to differ greatly in relation to species, site and environmental conditions. However, very similar dynamics of cambial activity and wood formation are observed in temperate and boreal zones. Here, we compared weekly xylem cell production and variation in stem circumference in the main northern hemisphere conifer species (genera Picea, Pinus, Abies and Larix) from 1996 to 2003. Dynamics of radial growth were modeled with a Gompertz function, defining the upper asymptote (A), x-axis placement (beta) and rate of change (kappa). A strong linear relationship was found between the constants beta and kappa for both types of analysis. The slope of the linear regression, which corresponds to the time at which maximum growth rate occurred, appeared to converge towards the summer solstice. The maximum growth rate occurred around the time of maximum day length, and not during the warmest period of the year as previously suggested. The achievements of photoperiod could act as a growth constraint or a limit after which the rate of tree-ring formation tends to decrease, thus allowing plants to safely complete secondary cell wall lignification before winter.

Emanation thermal analysis - Ready to fulfill the future needs of materials characterization

Czech Academy of Sciences Publication Activity Database

Balek, Vladimír; Šubrt, Jan; Mitsuhashi, T.; Beckman, I. N.; Gyoryova, K.

2002-01-01

Roč. 67, č. 1 (2002), s. 15-35 ISSN 1418-2874 R&D Projects: GA MŠk LN00A028 Institutional research plan: CEZ:AV0Z4032918 Keywords : emanation thermal analysis * microstructure * sintering Subject RIV: CA - Inorganic Chemistry Impact factor: 0.598, year: 2002

Maximum Acceptable Vibrato Excursion as a Function of Vibrato Rate in Musicians and Non-musicians

DEFF Research Database (Denmark)

Vatti, Marianna; Santurette, Sébastien; Pontoppidan, Niels H.

2014-01-01

and, in most listeners, exhibited a peak at medium vibrato rates (5–7 Hz). Large across-subject variability was observed, and no significant effect of musical experience was found. Overall, most listeners were not solely sensitive to the vibrato excursion and there was a listener-dependent rate...... for which larger vibrato excursions were favored. The observed interaction between maximum excursion thresholds and vibrato rate may be due to the listeners’ judgments relying on cues provided by the rate of frequency changes (RFC) rather than excursion per se. Further studies are needed to evaluate......Human vibrato is mainly characterized by two parameters: vibrato extent and vibrato rate. These parameters have been found to exhibit an interaction both in physical recordings of singers’ voices and in listener’s preference ratings. This study was concerned with the way in which the maximum...

LASER: A Maximum Likelihood Toolkit for Detecting Temporal Shifts in Diversification Rates From Molecular Phylogenies

Directory of Open Access Journals (Sweden)

Daniel L. Rabosky

2006-01-01

Full Text Available Rates of species origination and extinction can vary over time during evolutionary radiations, and it is possible to reconstruct the history of diversification using molecular phylogenies of extant taxa only. Maximum likelihood methods provide a useful framework for inferring temporal variation in diversification rates. LASER is a package for the R programming environment that implements maximum likelihood methods based on the birth-death process to test whether diversification rates have changed over time. LASER contrasts the likelihood of phylogenetic data under models where diversification rates have changed over time to alternative models where rates have remained constant over time. Major strengths of the package include the ability to detect temporal increases in diversification rates and the inference of diversification parameters under multiple rate-variable models of diversification. The program and associated documentation are freely available from the R package archive at http://cran.r-project.org.

Maximum entropy production rate in quantum thermodynamics

Energy Technology Data Exchange (ETDEWEB)

Beretta, Gian Paolo, E-mail: beretta@ing.unibs.i [Universita di Brescia, via Branze 38, 25123 Brescia (Italy)

2010-06-01

In the framework of the recent quest for well-behaved nonlinear extensions of the traditional Schroedinger-von Neumann unitary dynamics that could provide fundamental explanations of recent experimental evidence of loss of quantum coherence at the microscopic level, a recent paper [Gheorghiu-Svirschevski 2001 Phys. Rev. A 63 054102] reproposes the nonlinear equation of motion proposed by the present author [see Beretta G P 1987 Found. Phys. 17 365 and references therein] for quantum (thermo)dynamics of a single isolated indivisible constituent system, such as a single particle, qubit, qudit, spin or atomic system, or a Bose-Einstein or Fermi-Dirac field. As already proved, such nonlinear dynamics entails a fundamental unifying microscopic proof and extension of Onsager's reciprocity and Callen's fluctuation-dissipation relations to all nonequilibrium states, close and far from thermodynamic equilibrium. In this paper we propose a brief but self-contained review of the main results already proved, including the explicit geometrical construction of the equation of motion from the steepest-entropy-ascent ansatz and its exact mathematical and conceptual equivalence with the maximal-entropy-generation variational-principle formulation presented in Gheorghiu-Svirschevski S 2001 Phys. Rev. A 63 022105. Moreover, we show how it can be extended to the case of a composite system to obtain the general form of the equation of motion, consistent with the demanding requirements of strong separability and of compatibility with general thermodynamics principles. The irreversible term in the equation of motion describes the spontaneous attraction of the state operator in the direction of steepest entropy ascent, thus implementing the maximum entropy production principle in quantum theory. The time rate at which the path of steepest entropy ascent is followed has so far been left unspecified. As a step towards the identification of such rate, here we propose a possible

Use of emanation thermal analysis to characterize thermal reactivity of brannerite mineral

Czech Academy of Sciences Publication Activity Database

Balek, V.; Vance, E.R.; Zeleňák, V.; Málek, Z.; Šubrt, Jan

2007-01-01

Roč. 88, č. 1 (2007), s. 93-98 ISSN 1388-6150 Grant - others:GA MŠk(CZ) LA 292; GA MŠk(CZ) ME 879 Institutional research plan: CEZ:AV0Z40320502 Keywords : brannerite * emanation thermal analysis Subject RIV: CA - Inorganic Chemistry Impact factor: 1.483, year: 2007

Helium and radon-emanation bibliography. Selected references of geologic interest to uranium exploration

International Nuclear Information System (INIS)

Adkisson, C.W.; Reimer, G.M.

1976-01-01

Selected references on helium and radon gas emanations and geologically related topics are given. There are 172 references primarily related to helium geology, 129 to radon geology, and 171 to helium and radon. These references are of geologic interest to uranium exploration

Emanation thermal analysis study of the preparation of ruthenia-titania-based finely dispersed powders

Czech Academy of Sciences Publication Activity Database

Balek, V.; Mitsuhashi, T.; Zeleňák, V.; Večerníková, Eva; Šubrt, Jan; Haneda, H.; Bezdička, Petr

2002-01-01

Roč. 248, č. 1 (2002), s. 47-53 ISSN 0021-9797 Institutional research plan: CEZ:AV0Z4032918 Keywords : emanation thermal analysis * TiO2 * RuO2 Subject RIV: CA - Inorganic Chemistry Impact factor: 1.466, year: 2002

7 CFR 4290.845 - Maximum rate of amortization on Loans and Debt Securities.

Science.gov (United States)

2010-01-01

...) RURAL BUSINESS-COOPERATIVE SERVICE AND RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE RURAL BUSINESS INVESTMENT COMPANY (âRBICâ) PROGRAM Financing of Enterprises by RBICs Structuring Rbic Financing of Eligible Enterprises-Types of Financings § 4290.845 Maximum rate of amortization on Loans and Debt Securities. The...

Noninvasive analysis of volatile biomarkers in human emanations for health and early disease diagnosis.

Science.gov (United States)

Kataoka, Hiroyuki; Saito, Keita; Kato, Hisato; Masuda, Kazufumi

2013-06-01

Early disease diagnosis is crucial for human healthcare and successful therapy. Since any changes in homeostatic balance can alter human emanations, the components of breath exhalations and skin emissions may be diagnostic biomarkers for various diseases and metabolic disorders. Since hundreds of endogenous and exogenous volatile organic compounds (VOCs) are released from the human body, analysis of these VOCs may be a noninvasive, painless, and easy diagnostic tool. Sampling and preconcentration by sorbent tubes/traps and solid-phase microextraction, in combination with GC or GC-MS, are usually used to analyze VOCs. In addition, GC-MS-olfactometry is useful for simultaneous analysis of odorants and odor quality. Direct MS techniques are also useful for the online real-time detection of VOCs. This review focuses on recent developments in sampling and analysis of volatile biomarkers in human odors and/or emanations, and discusses future use of VOC analysis.

Radon and Thoron emanation testwork on Nolans Rare Earths ores

International Nuclear Information System (INIS)

Sonter, Mark; Grose, Jeremy

2016-01-01

This paper reports on a series of experiments performed on two bulk ore samples for Arafura Resources' Nolans Rare Earths project, intended to derive information on radon (Rn222) and thoron (Rn220) emanation rates (fluxes) under various circumstances. This data is needed to enable development of predictions of Rn and Tn releases from exposed mine bench ore, ore stockpiles, and tailings, and thus assist in estimation of airborne concentrations within the areas of the future Mine and Processing plant. In turn these estimates will provide guidance on the quantitative risk and the necessity or otherwise of invoking specific control measures, either in design or in operating procedures. This testwork was carried out during the period 2nd to 15th July, at Arafura's Winnellie facility in Darwin. Conclusions are that for uncrushed ore, Rn flux numbers are around 1.0Bq/m"2/s, Tn numbers appear to cluster around 200-300 Bq/m"2/s. Crushing gave no change in Rn flux, Tn flux was doubled for calc-silicate material. Wetting gave significant reductions for both Rn and Tn for ores sampled, and clay capping reduced Rn flux marginally but Tn was reduced by a factor of 100.

New England observed and predicted August stream/river temperature maximum daily rate of change points

Data.gov (United States)

U.S. Environmental Protection Agency — The shapefile contains points with associated observed and predicted August stream/river temperature maximum negative rate of change in New England based on a...

Fluoride emanations from fatories: experimental study of the action of fluorine plants

Energy Technology Data Exchange (ETDEWEB)

Cristiani, H; Gautier, R

1925-01-01

Research work from 1883 onward and the author's own experiments on the damages done to plants by fluoric emanations from aluminum and/or chemical fertilizer factories are reviewed. Fluoric compounds may act through the soil and water that feed the plants, or directly on the plant organs exposed to fluorine-polluted air. Of the various toxic gases, hydrofluoric acid is the most noxious since it forms thick fogs with the humidity in the air. The effects are cumulative and may not become visible before repeated exposure of the plants to the gases. The toxic action of NaF derives from its ability to precipitate lime and to attach itself to other substances, such as proteins. Also, fluorine salts have antiseptic action on unicellular elements, and this has had practical applications. At the doses utilized, alkaline salts of fluorine do not precipitate albumin, and can hamper microbial growth. On the other hand, examination of plant lesions enables the detection of their fluoric, as opposed to other (sulfur, chlorine) origin. Stoklasa claims that the amount of emanation and smoke has increased 100-fold in the last century, reducing the crops in some regions by 30 to 90%. The work on fodder from industrial areas was confirmed by experiments with fluorine compounds in air and in water.

Emanation of radon-222 in uraniferous phosphorite from Pernambuco, Brazil; Emanação de radônio-222 em fosforito uranífero de Pernambuco

Energy Technology Data Exchange (ETDEWEB)

Santos, M.L.O.; França, E.J.; Amaral, D.S.; Silva, K.E.M.; Hazin, C.A.; Farias, E.E.G., E-mail: emersonemiliano@yahoo.com.br [Centro Regional de Ciências Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

2017-07-01

The concentration of radon-222 activity available for transport to the surface through the pore space can be defined as radon emanation. From the decay of radium-226, whose half-life is 1850 years, it is associated with the development of neoplasia, such as lung cancer. In the Metropolitan Region of Recife, sedimentary rocks known as phosphorites have been known since 1959, so, from the radiometric characterization of the Paulista and Igarassu Municipality, in Pernambuco, emanation tests were carried out, aiming to determine the emanation power of radon in samples of uraniferous phosphorite from the Recife Metropolitan Region. Initially, 6 independent samples of phosphorites with activity concentration of {sup 226}Ra> 400 Bq kg{sup -1} were comminuted. Portions of 5g were conditioned in a radon chamber with 500 mL volume for measurements. The linear fit of the model converged after 200 interactions with selection of the best fit by the Chi-Square test, through the Origin® 8.0 program. After analysis of the samples, radon emanation power was estimated in the range of 7% to 15%, with a mean value of 10.8%. The methodology used to determine the emanation parameters in samples of uraniferous phosphorite was adequate, observing an inversely proportional relation between the concentration of the radium-226 and the emanation power.

Analysis of reaction schemes using maximum rates of constituent steps

Science.gov (United States)

Motagamwala, Ali Hussain; Dumesic, James A.

2016-01-01

We show that the steady-state kinetics of a chemical reaction can be analyzed analytically in terms of proposed reaction schemes composed of series of steps with stoichiometric numbers equal to unity by calculating the maximum rates of the constituent steps, rmax,i, assuming that all of the remaining steps are quasi-equilibrated. Analytical expressions can be derived in terms of rmax,i to calculate degrees of rate control for each step to determine the extent to which each step controls the rate of the overall stoichiometric reaction. The values of rmax,i can be used to predict the rate of the overall stoichiometric reaction, making it possible to estimate the observed reaction kinetics. This approach can be used for catalytic reactions to identify transition states and adsorbed species that are important in controlling catalyst performance, such that detailed calculations using electronic structure calculations (e.g., density functional theory) can be carried out for these species, whereas more approximate methods (e.g., scaling relations) are used for the remaining species. This approach to assess the feasibility of proposed reaction schemes is exact for reaction schemes where the stoichiometric coefficients of the constituent steps are equal to unity and the most abundant adsorbed species are in quasi-equilibrium with the gas phase and can be used in an approximate manner to probe the performance of more general reaction schemes, followed by more detailed analyses using full microkinetic models to determine the surface coverages by adsorbed species and the degrees of rate control of the elementary steps. PMID:27162366

The use of geochemical barriers for reducing contaminants emanating from uranium mill tailings

International Nuclear Information System (INIS)

Groffman, A.R.; Longmire, P.; Mukhopadhyay, B.; Downs, W.

1991-01-01

A problem facing the Department of Energy's Uranium Mill Tailings Remediation Action (UMTRA) Project is the contamination of local ground water by leachate emanating form the tailings piles. These fluids have a low pH and contain heavy metals and trace elements such as arsenic, molybdenum, nitrate, selenium, and uranium. In order to meet ground water standards low hydraulic conductivity covers are installed over the tailings embankment. in some cases it may be necessary to install a geochemical barrier down gradient from the tailings embankment in order to remove the hazardous constituents. By using geochemical barriers to reduce undesirable species form a contaminant plume, fluids emanating form beneath a repository can in effect be scrubbed before entering the water table. Materials containing adsorbing clays, iron oxyhydroxides and zeolites, and reducing materials such as coal and peat, are being used effectively to attenuate contaminants form uranium mill tailings. Experiments to directly determine attenuation capacities of selected buffer/adsorption materials were conducted in the laboratory. Batch leach tests were conducted in lieu of column tests when the hydraulic conductivity of materials was too low to use in columns and shales

Divine Emanation As Cosmic Origin: Ibn Sînâ and His Critics

Directory of Open Access Journals (Sweden)

Syamsuddin Arif

2012-11-01

Full Text Available The question of cosmic beginning has always attracted considerable attention from serious thinkers past and present. Among many contesting theories that have emerged, that of emanation was appropriated by Muslim philosophers like Ibn Sînâ in order to reconcile the Aristotelian doctrine of the eternity of matter with the teaching of al-Qur’ân on the One Creator-God. According to this theory, the universe, which comprises a multitude of  entities, is generated from a transcendent Being, the One, that is unitary, through the medium of  a hierarchy of  immaterial substances. While the ultimate source is undiminished, the beings which are emanated are progressively less perfect as they are further removed from the first principle. The process is conceived as being atemporal and often compared to the efflux of light from a luminous body, or to water flowing from a spring. This metaphysical theory has enabled Ibn Sînâ to solve the vexed problem: given an eternally existing world and one eternally existing God, how can the two necessarily co-exist without having the perfect, simple unity of God destroyed by contact with the multiplicity of material things? The following essay delineates and evaluates both Ibn Sînâ’s arguments as well as the counter-arguments of  his critics.

Effects of the spatial repellent metofluthrin on landing rates of outdoor biting anophelines in Cambodia, Southeast Asia.

Science.gov (United States)

Charlwood, J D; Nenhep, S; Protopopoff, N; Sovannaroth, S; Morgan, J C; Hemingway, J

2016-06-01

The emergence of artemisinin-resistant malaria in Southeast Asia is a major problem. The fact that many people become infected with malaria when they are outside has prompted the development of 'spatial' rather than topical repellents. The respective effects of one or four slow-release emanators of metofluthrin, a pyrethroid, were tested in Pailin, Pursat and Koh Kong, Cambodia. Numbers of mosquitoes counted in outdoor landing catches when one or four emanators were suspended close to the collector were compared with control collections. In Pailin, the effects of emanators on catches in Furvela tent traps and Centers for Disease Control (CDC) light traps suspended underneath houses were also investigated. Rate ratios were used to determine differences. A total of 29 255 mosquitoes were collected over 2934 h of landing collections, 87 nights of tent trapping and 81 nights of light trap capture. In Pailin, landing rates were reduced by 48% by a single emanator and by 67% by four emanators (P metofluthrin collections (P > 0.05). These findings suggest that although the product can produce a significant effect, it requires further improvement. © 2016 The Royal Entomological Society.

The Applicability of Traditional Protection Methods to Lines Emanating from VSC-HVDC Interconnectors and a Novel Protection Principle

Directory of Open Access Journals (Sweden)

Shimin Xue

2016-05-01

Full Text Available Voltage source converter (VSC-based high voltage direct current (VSC-HVDC interconnectors can realize accurate and fast control of power transmission among AC networks, and provide emergency power support for AC networks. VSC-HVDC interconnectors bring exclusive fault characteristics to AC networks, thus influencing the performance of traditional protections. Since fault characteristics are related to the control schemes of interconnectors, a fault ride-through (FRT strategy which is applicable to the interconnector operating characteristic of working in four quadrants and capable of eliminating negative-sequence currents under unbalanced fault conditions is proposed first. Then, the additional terms of measured impedances of distance relays caused by fault resistances are derived using a symmetrical component method. Theoretical analysis shows the output currents of interconnectors are controllable after faults, which may cause malfunctions in distance protections installed on lines emanating from interconnectors under the effect of fault resistances. Pilot protection is also inapplicable to lines emanating from interconnectors. Furthermore, a novel pilot protection principle based on the ratio between phase currents and the ratio between negative-sequence currents flowing through both sides is proposed for lines emanating from the interconnectors whose control scheme aims at eliminating negative-sequence currents. The validity of theoretical analysis and the protection principle is verified by PSCAD/EMTDC simulations.

Effects of barium chlorine treatment of uranium ore on 222Rn emanation and 226Ra leachability from mill tailings

International Nuclear Information System (INIS)

Ibrahim, S.A.; Church, S.L.; Whicker, F.W.

1985-01-01

The purpose of this laboratory study was to investigate the effectiveness of barium chloride treatment of uranium ore on 222 Rn emanation from mill tailings, 226 Ra level in waste-water, and the leachability of radium from tailings. It has been shown that barium sulfate is an excellent carrier for radium and that barium sulfate crystals have high retention capacity for radon gas produced by radium trapped within the lattice. Ground uranium ore from a mine in Wyoming was mixed with water to form a 1:1 ratio before barium and potassium chlorides were added at concentrations of 0, 10, 25, 50, and 100 mg per liter of slurry. The ore was then subjected to a simulated mill process using sulfuric acid leaching. The liquid representing tailings pond water was separated and analyzed for 226 Ra and the solid fraction, representing mill tailings, was tested for radon emanation and the leachability of radium by deionized water. This study suggests that barium treatment of uranium ore prior to sulfuric acid leaching could be effective in reducing radon emanation from tailings and also in reducing the 226 Ra concentration of waste-water. Leachability of radium from treated tailings was markedly reduced

New England observed and predicted August stream/river temperature maximum positive daily rate of change points

Data.gov (United States)

U.S. Environmental Protection Agency — The shapefile contains points with associated observed and predicted August stream/river temperature maximum positive daily rate of change in New England based on a...

New England observed and predicted July stream/river temperature maximum positive daily rate of change points

Data.gov (United States)

U.S. Environmental Protection Agency — The shapefile contains points with associated observed and predicted July stream/river temperature maximum positive daily rate of change in New England based on a...

New England observed and predicted July maximum negative stream/river temperature daily rate of change points

Data.gov (United States)

U.S. Environmental Protection Agency — The shapefile contains points with associated observed and predicted July stream/river temperature maximum negative daily rate of change in New England based on a...

Effects of barium chloride treatment of uranium mill tailings and ore on radon emanation and 226Ra levels. Progress report

International Nuclear Information System (INIS)

Ibrahim, S.A.; Flot, S.L.

1983-01-01

The purpose of this study was to investigate the effect of barium chloride treatments on: reduction of 222 Rn emanation from mill wastes; reduction of 226 Ra levels in wastewater; and decreased leachability of 226 Ra from mill wastes. Baseline 226 Ra concentrations were determined for ore and tailings as well as radon emanation fractions. Uranium ore was treated with soluble barium at concentrations of 10, 25, 50, and 100 mg per litre of slurry. The leach-liquor declined in 226 Ra concentration by as much as 50%. When soluble potassium as well as barium was used in the treatment process at equal concentrations of 10, 25, 50, and 100 mg per litre of slurry, a similar reduction was observed. No significant difference was noted between the two treatment regimes. An accelerated leaching experiment was performed on the ore treated with barium chloride. All treatment groups except that treated with 10 mg of soluble barium per litre of slurry showed significant decreases in leachability. Available 222 Rn (corresponds with radon emanation fraction) was measured in treated and untreated ore. Ore treated with concentrations of Ba ++ up to 1.00 mg per gram of ore did not show a statistically significant reduction in available 222 Rn, however when potassium sulfate was also added, a significant decline was noted. This study suggests that barium chloride treatments reduce radon emanation from mill wastes and reduce 226 Ra levels in wastewater. Leachability of 226 Ra from treated samples decreased markedly. 19 references, 8 figures, 7 tables

Radiological assessment of the utilization of fly ash in concrete for building construction and the parameters affecting radon-222 emanation from fly ash concrete

International Nuclear Information System (INIS)

Hwang, J.G.

1986-01-01

In this study, the Rn-222 area exhalation rates and the maximum area exhalations for concrete containing fly ash or Ra-226 water were measured. Various concrete samples were fabricated with fly ash of known radium content as a cement substitute. Other samples were prepared with one of three concentrations of Ra-226 water solution added into the concrete mix. A newly designed Indoor/Outdoor Emanation Chamber. The Ra-225 concentrations for the fly ash used ranged from 3.42 pCi/g to 7.55 pCi/g depending upon the source of the ash and the particle size. Doses were calculated for occupants of a hypothetical house built with concrete of the type studied. Doses to the basal cells of the bronchial epithelium and the mean dose to the lung were 2.10 rad/yr and 0.37 rad/yr for standard concrete, up to 4.28 rad/yr and 0.76 rad/yr for fly ash concrete, and 3.26 rad/yr and 0.58 rad/yr for the concrete made with 25 pCI/L radium-226 water. The risk associated with utilization of standard concrete in an unventilated house was estimated to range from 560 to 1316 fatal cancers in million population. Utilization of fly ash as a cement substitute could increase the number of fatal lung cancers up to 2680. Introducing 25 pCi/L Ra-226 water into concrete will increase the fatal cancer rate up to 2042 in a million population

Emanation thermal analysis. Application in solid state chemistry, analytical chemistry and engineering

International Nuclear Information System (INIS)

Balek, V.; Tel'deshi, Yu.

1986-01-01

Voluminous material on application of emenation thermal analysis for investigation of solids is systematized. General concepts and historical review of development of the method are given. Methods of introduction of inert gases into solids are considered. Theoretical aspects of inert gas evolution from solids labelled by radioactive gas or its maternal isotope are stated. The methods for measuring inert gases are considered. The possibilities, limitations and perspectives of development of radiometric emanation methods for the solution of various problems of analytical chemistry and thechnology are discussed

30 CFR 75.601-3 - Short circuit protection; dual element fuses; current ratings; maximum values.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Short circuit protection; dual element fuses... Trailing Cables § 75.601-3 Short circuit protection; dual element fuses; current ratings; maximum values. Dual element fuses having adequate current-interrupting capacity shall meet the requirements for short...

Detailed radon emanation mapping in Northern Latium

International Nuclear Information System (INIS)

Aumento, F.

1993-01-01

Detailed radon surveys over 5,000 km 2 of Northern Latium, covering the northern part of the volcanic province of Central Italy, commenced in the mid eighties as part of a geothermal exploration programme; the surveys have subsequently been continued and amplified with environmental protection in mind. The area is now covered by ground emission maps, radon levels in water supplies, emissions from the different lithologies and concentrations in houses. The high uraniferous content of the volcanics, the porous nature of the ubiquitous pyroclastics, and active geothermal systems in the area combine to convey to ground level high concentrations of radon. The emissions show strong lateral variations which are geologically and tectonically controlled, such that only detailed surveys reveal the extent and locations of anomalous radon emanations. Unfortunately, long ago towns often developed in strategic locations. For Northern Latium this means on volcanic highs formed by faulted tuff blocks, two geological features associated with particularly high radon emissions. As a result, in contrast to the low average indoor radon concentrations for the greater part of Italy, in some of these town the average values exceed 450 Bq/m 3 . (author). 1 fig

Determination of radioactivity in and radon emanation coefficient of selected building materials and estimation of radiation exposure from their use

International Nuclear Information System (INIS)

Paredes, C.H.

1984-01-01

Building materials commonly used in the construction industry and those that were manufactured with waste products of the phosphate industry, and phosphate ores were examined for radioactivity content. Each material was analyzed for Ra-226, Ra-228, and K-40 by gamma-ray spectrometry. The measured radionuclide concentrations for the building materials examined ranged from 0.2-3.9 pCi g -1 for Ra-226, 0.3-1.8 pCi g -1 for Ra-228, and 2.3-37 pCi g -1 for K-40. Waste products of elemental phosphorus manufacture had activity concentrations that ranged from 4.2-54 pCi g -1 for Ra-226, 0.3-1.0 pCi g -1 for Ra-228, and 1.4-6.6 pCi g -1 for K-40. The activity concentrations for phosphate ores from Tennessee and Montana were 5.3 and 36 pCi g -1 for Ra-226, 0.5 and 0.6 pCi g -1 for Ra-228, and 4.8 and 9.0 pCi g -1 for K-40, respectively. The emanation coefficients for the building materials examined ranged from 6.86 x 10 -4 - 5.99 x 10 -2 . Those for the waste products of the phosphate industry ranged from 2.21 x 10 -4 - 3.06 x 10 -2 . The phosphate ores had emanation coefficients in the order of 10 -2 . The emanation coefficients for mineral wool and wall-board slightly increased when measured at a relative humidity of 100% instead of 0%. No dependence of emanation coefficient on humidity was observed for Tenn. phosphate slag

ReplacementMatrix: a web server for maximum-likelihood estimation of amino acid replacement rate matrices.

Science.gov (United States)

Dang, Cuong Cao; Lefort, Vincent; Le, Vinh Sy; Le, Quang Si; Gascuel, Olivier

2011-10-01

Amino acid replacement rate matrices are an essential basis of protein studies (e.g. in phylogenetics and alignment). A number of general purpose matrices have been proposed (e.g. JTT, WAG, LG) since the seminal work of Margaret Dayhoff and co-workers. However, it has been shown that matrices specific to certain protein groups (e.g. mitochondrial) or life domains (e.g. viruses) differ significantly from general average matrices, and thus perform better when applied to the data to which they are dedicated. This Web server implements the maximum-likelihood estimation procedure that was used to estimate LG, and provides a number of tools and facilities. Users upload a set of multiple protein alignments from their domain of interest and receive the resulting matrix by email, along with statistics and comparisons with other matrices. A non-parametric bootstrap is performed optionally to assess the variability of replacement rate estimates. Maximum-likelihood trees, inferred using the estimated rate matrix, are also computed optionally for each input alignment. Finely tuned procedures and up-to-date ML software (PhyML 3.0, XRATE) are combined to perform all these heavy calculations on our clusters. http://www.atgc-montpellier.fr/ReplacementMatrix/ olivier.gascuel@lirmm.fr Supplementary data are available at http://www.atgc-montpellier.fr/ReplacementMatrix/

Hazardous waste disposal in relationship to radon gas emanation in atmosphere

International Nuclear Information System (INIS)

Fang, H.Y.

1990-01-01

Radioactive/toxic radon gas (Rn) produced naturally in the ground by the normal decay of uranium (U) and radium (Ra) is widely distributed in trace amounts in the earth's crust. It is a colorless, odorless and tasteless element and is one of the six generally known noble gases which are inert gases lacking the usual or anticipated chemical or biological action. Most radon gas is concentrated in the oxidation belt which is at a relatively shallow depth from the ground surface. Under normal conditions, the amount of radon gas seeping into the atmosphere or entering into residential buildings is very little and will not be harmful to human health. In recent years, due to population growth, a progressive living standard and industrial progress, many natural farm lands, forests and wetlands have been destroyed by conversion into residential and industrial compounds; consequently, such construction activities and industrial waste disposal changes the dynamic equilibrium of the ecosystem which can trigger and accelerate radon gas emanation and mobilization. This change is the major reason for the problem of indoor radon concentration which has significantly increased in recent years. Recent findings indicate that radon is not a totally inert element as previously thought. It can be influenced by local environments such as temperature, pH value, ion exchange, redox reaction, etc. to some degree. Also radon gas interacts with soil, water, air and others; unfortunately, the interface mechanisms between radon and the environment are not yet clearly understood and little information on these aspects is available. In this paper only the hazardous waste disposal causes for radon emanation are discussed. To deal with such complex phenomena, a new approach is presented that assumes radon gas interaction with the environment through dust in the air and suspensions in the water and soil-water system

Maximum heart rate in brown trout (Salmo trutta fario) is not limited by firing rate of pacemaker cells.

Science.gov (United States)

Haverinen, Jaakko; Abramochkin, Denis V; Kamkin, Andre; Vornanen, Matti

2017-02-01

Temperature-induced changes in cardiac output (Q̇) in fish are largely dependent on thermal modulation of heart rate (f H ), and at high temperatures Q̇ collapses due to heat-dependent depression of f H This study tests the hypothesis that firing rate of sinoatrial pacemaker cells sets the upper thermal limit of f H in vivo. To this end, temperature dependence of action potential (AP) frequency of enzymatically isolated pacemaker cells (pacemaker rate, f PM ), spontaneous beating rate of isolated sinoatrial preparations (f SA ), and in vivo f H of the cold-acclimated (4°C) brown trout (Salmo trutta fario) were compared under acute thermal challenges. With rising temperature, f PM steadily increased because of the acceleration of diastolic depolarization and shortening of AP duration up to the break point temperature (T BP ) of 24.0 ± 0.37°C, at which point the electrical activity abruptly ceased. The maximum f PM at T BP was much higher [193 ± 21.0 beats per minute (bpm)] than the peak f SA (94.3 ± 6.0 bpm at 24.1°C) or peak f H (76.7 ± 2.4 at 15.7 ± 0.82°C) (P brown trout in vivo. Copyright © 2017 the American Physiological Society.

Calibration of a degassing-emanation line for 222Rn determination in seawater samples

International Nuclear Information System (INIS)

Farias, Luciana Aparecida

2002-01-01

The purpose of this study is to calibrate a degassing-emanation line and to determine 222 Rn and 226 Ra activity concentrations in seawater samples. This methodology, also called Lucas method, consists in the extraction of radon (originally dissolved in seawater), collection of the gas in a liquid nitrogen cold trap and transfer from the trap to an alpha scintillation cell. Total extraction efficiencies of the 4 degassing-emanation systems were determined by measuring 226 Ra reference solutions. The efficiencies obtained for these 4 systems varied from 21 % to 62%. This work also presents preliminary results of a study carried out in a series of small embayements of Ubatuba, Sao Paulo State-Brazil: Flamengo Bay, Fortaleza Bay, Mar Virado Bay and Ubatuba Bay. Concentration of Rn in excess varied from 0,011 to 0,317 Bq/L for Flamengo Bay, from 0,009 to 0,130 Bq/L for Fortaleza Bay, from 0,018 to 0,050 Bq/L for Mar Virado Bay and from 0,004 to 0,120 Bq/L for Ubatuba Bay. The results obtained for the concentration of 222 Rn in excess in a transect at Flamengo Bay varied from 0,002 to 0,036 Bq/L. Higher concentrations of 222 Rn in excess were obtained in Flamengo Bay, Fortaleza Bay and Ubatuba bay. It was also observed that the concentration of 222 Rn in excess increases with depth, as expected. (author)

Clinical evaluation of a simple uroflowmeter for categorization of maximum urinary flow rate

Directory of Open Access Journals (Sweden)

Simon Pridgeon

2007-01-01

Full Text Available Objective: To evaluate the accuracy and diagnostic usefulness of a disposable flowmeter consisting of a plastic funnel with a spout divided into three chambers. Materials and Methods: Men with lower urinary tract symptoms (LUTS voided sequentially into a standard flowmeter and the funnel device recording maximum flow rate (Q max and voided volume (V void . The device was precalibrated such that filling of the bottom, middle and top chambers categorized maximum input flows as 15 ml s -1 respectively. Subjects who agreed to use the funnel device at home obtained readings of flow category and V void twice daily for seven days. Results: A single office reading in 46 men using the device showed good agreement with standard measurement of Q max for V void > 150 ml (Kappa = 0.68. All 14 men whose void reached the top chamber had standard Q max > 15 ml s -1 (PPV = 100%, NPV = 72% whilst eight of 12 men whose void remained in the bottom chamber had standard Q max < 10 ml s -1 (PPV = 70%, NPV = 94%. During multiple home use by 14 men the device showed moderate repeatability (Kappa = 0.58 and correctly categorized Q max in comparison to standard measurement for 12 (87% men. Conclusions: This study suggests that the device has sufficient accuracy and reliability for initial flow rate assessment in men with LUTS. The device can provide a single measurement or alternatively multiple home measurements to categorize men with Q max < 15 ml s -1 .

Emanation of /sup 232/U daughter products from submicrometer particles of uranium oxide and thorium dioxide by nuclear recoil and inert gas diffusion

Energy Technology Data Exchange (ETDEWEB)

Coombs, M.A.; Cuddihy, R.G. (Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (USA). Inhalation Toxicology Research Inst.)

1983-01-01

Emanation of /sup 232/U daughter products by nuclear recoil and inert gas diffusion from spherical, submicrometer particles of uranium oxide and thorium dioxide was studied. Monodisperse samples of particles containing 1% /sup 232/U and having physical diameters between 0.1 and 1 ..mu..m were used for the emanation measurements. Thorium-228 ions recoiling from the particles after alpha-decay of /sup 232/U were collected electrostatically on a recoil cathode. Radon-220 diffusing from the particles was swept by an airstream into a 4 l. chamber where the /sup 220/Rn daughters were collected on a second cathode. Mathematical models of radionuclide emanation from spherical particles were used to calculate the recoil range of /sup 228/Th and the diffusion coefficient of /sup 220/Rn in the particle matrix. A /sup 228/Th recoil range of 0.02 ..mu..m and a /sup 220/Rn diffusion coefficient of 3 x 10/sup -14/ cm/sup 2//sec were obtained in both uranium oxide and thorium dioxide particles.

A charcoal canister survey of radon emanation at the rehabilitated uranium mine site at Nabarlek

International Nuclear Information System (INIS)

Storm, J.R.; Patterson, J.R.

1999-01-01

This paper describes a recent survey of radon emanation measurements from the rehabilitated Nabarlek mine site. It was mined out in 1979, decommissioned in 1995 and provided a good test bed for assessment of rehabilitation in terms of radon flux attenuation. Measurements have been made with charcoal canisters. Studies to measure the radon-220 flux by observing Tl-208 progeny of thoron the effectiveness of trial covers and meteorological considerations will be reported

A charcoal canister survey of radon emanation at the rehabilitated uranium mine site at Nabarlek

Energy Technology Data Exchange (ETDEWEB)

Storm, J R; Patterson, J R [University of Adelaide, Adelaide, SA (Australia). Department of Physics and Mathematical Physics

1999-07-01

This paper describes a recent survey of radon emanation measurements from the rehabilitated Nabarlek mine site. It was mined out in 1979, decommissioned in 1995 and provided a good test bed for assessment of rehabilitation in terms of radon flux attenuation. Measurements have been made with charcoal canisters. Studies to measure the radon-220 flux by observing Tl-208 progeny of thoron the effectiveness of trial covers and meteorological considerations will be reported.

AEROSOL NUCLEATION AND GROWTH DURING LAMINAR TUBE FLOW: MAXIMUM SATURATIONS AND NUCLEATION RATES. (R827354C008)

Science.gov (United States)

An approximate method of estimating the maximum saturation, the nucleation rate, and the total number nucleated per second during the laminar flow of a hot vapour–gas mixture along a tube with cold walls is described. The basis of the approach is that the temperature an...

22 CFR 201.67 - Maximum freight charges.

Science.gov (United States)

2010-04-01

..., commodity rate classification, quantity, vessel flag category (U.S.-or foreign-flag), choice of ports, and... the United States. (2) Maximum charter rates. (i) USAID will not finance ocean freight under any... owner(s). (4) Maximum liner rates. USAID will not finance ocean freight for a cargo liner shipment at a...

Radiometric maps of Israel - Partial contribution to the understanding of potential radon emanations

International Nuclear Information System (INIS)

Vulkan, U.; Shirav, M.

1997-01-01

An airborne radiometric survey over parts of Israel was carried out in 1981. The system was comprised from 10 Nal 4 inch x 4 inch x 16 inch detectors, arranged in 4,4 and 2 sensors, with total volume of 1560 inch 3 , and one 4 inch x 4 inch x 16 inch uplooking Nal detector. Flight nominal height was 400 feet. It was found that the Mount Scopus Group (of Senonian origin) is the main source for high uranium - phosphorite rocks of this group contain up to 150 ppm U. Comparing the eU radiometric map with a map of potential radon emanation from rock units, reveals a fair correlation - high radon emanation usually follow the distribution of the Mount Scopus Group in Israel. The correlation between the two maps is excellent over arid terrain where soil cover is missing, whereas over semi-arid - humid areas (western and northern Israel), where soil and cultivation covers are developed, the eU levels over Mount Scopus Group's outcrops are much lower due to absorption of the radiation, and do not depict the full radon potential. Detailed mapping of radon hazards usually exhibit poor correlation between airborne eU data and direct pore radon measurements, even in arid terrain. This phenomenon is attributed to the fact that a radon ''source rock'' (e.g. phosphorite) could be covered with a few up to some tenths of meters of uranium-barren rock. About 0.5 meter cover is enough to absorb all radiation, causing very low airborne eU readings, while the radon free way in this rock is about 10 meters, yielding high pore radon levels when directly measured

Imaging VLBI polarimetry data from Active Galactic Nuclei using the Maximum Entropy Method

Directory of Open Access Journals (Sweden)

Coughlan Colm P.

2013-12-01

Full Text Available Mapping the relativistic jets emanating from AGN requires the use of a deconvolution algorithm to account for the effects of missing baseline spacings. The CLEAN algorithm is the most commonly used algorithm in VLBI imaging today and is suitable for imaging polarisation data. The Maximum Entropy Method (MEM is presented as an alternative with some advantages over the CLEAN algorithm, including better spatial resolution and a more rigorous and unbiased approach to deconvolution. We have developed a MEM code suitable for deconvolving VLBI polarisation data. Monte Carlo simulations investigating the performance of CLEAN and the MEM code on a variety of source types are being carried out. Real polarisation (VLBA data taken at multiple wavelengths have also been deconvolved using MEM, and several of the resulting polarisation and Faraday rotation maps are presented and discussed.

Maximum permissible continuous release rates of phosphorus-32 and sulphur-35 to atmosphere in a milk producing area

Energy Technology Data Exchange (ETDEWEB)

Bryant, P M

1963-01-01

A method is given for calculating, for design purposes, the maximum permissible continuous release rates of phosphorus-32 and sulphur-35 to atmosphere with respect to milk contamination. In the absence of authoritative advice from the Medical Research Council, provisional working levels for the concentration of phosphorus-32 and sulphur-35 in milk are derived, and details are given of the agricultural assumptions involved in the calculation of the relationship between the amount of the nuclide deposited on grassland and that to be found in milk. The agricultural and meteorological conditions assumed are applicable as an annual average to England and Wales. The results (in mc/day) for phosphorus-32 and sulphur-35 for a number of stack heights and distances are shown graphically; typical values, quoted in a table, include 20 mc/day of phosphorus-32 and 30 mc/day of sulfur-35 as the maximum permissible continuous release rates with respect to ground level releases at a distance of 200 metres from pastureland.

Maximum type I error rate inflation from sample size reassessment when investigators are blind to treatment labels.

Science.gov (United States)

Żebrowska, Magdalena; Posch, Martin; Magirr, Dominic

2016-05-30

Consider a parallel group trial for the comparison of an experimental treatment to a control, where the second-stage sample size may depend on the blinded primary endpoint data as well as on additional blinded data from a secondary endpoint. For the setting of normally distributed endpoints, we demonstrate that this may lead to an inflation of the type I error rate if the null hypothesis holds for the primary but not the secondary endpoint. We derive upper bounds for the inflation of the type I error rate, both for trials that employ random allocation and for those that use block randomization. We illustrate the worst-case sample size reassessment rule in a case study. For both randomization strategies, the maximum type I error rate increases with the effect size in the secondary endpoint and the correlation between endpoints. The maximum inflation increases with smaller block sizes if information on the block size is used in the reassessment rule. Based on our findings, we do not question the well-established use of blinded sample size reassessment methods with nuisance parameter estimates computed from the blinded interim data of the primary endpoint. However, we demonstrate that the type I error rate control of these methods relies on the application of specific, binding, pre-planned and fully algorithmic sample size reassessment rules and does not extend to general or unplanned sample size adjustments based on blinded data. © 2015 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd. © 2015 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.

Stress intensity factors for deep cracks emanating from the corner formed by a hole intersecting a plate surface

Science.gov (United States)

Mcgowan, J. J.; Smith, C. W.

1976-01-01

The stress intensity factors (SIFs) at the end points of flaws emanating from the corner formed by the intersection of a plate with a hole were determined using stress freezing photoelasticity and a numerical technique known as the Taylor series correction method to extract the SIF values from the photoelastic data. The geometries studied were crack depth to thickness ratios of about 0.2, 0.5, and 0.75; crack depth to crack length ratios of about 1.0 to 2.0; and crack length to hole radius ratios of about 0.5 to 2.0. The SIFs were determined at the intersection of the flaw border with the plate surface (KS) and with the edge of the hole (KH). It is shown that extension of a crack emanating from a corner of intersection of a hole with a plate under monotonically increasing load is not self-similar and that as the flaw depth increases, KH decreases and KS increases. Existing theories and design criteria significantly overestimate the SIF at both the hole and the surface except for shallow flaws at the hole and deep flaws at the surface.

Radon exhalation rates from slate stone samples in Aravali Range in Haryana

International Nuclear Information System (INIS)

Upadhyay, S.B.; Kant, K.; Chakarvarti, S.K.

2012-01-01

The slate stone tiles are very popular in covering the walls of the rooms. Radon is released into ambient air from slate stones due to ubiquitous uranium and radium in them, thus increasing the airborne radon concentration. The radioactivity in slates stones is related to radioactivity in the rocks from which the slate stone tiles are formed. In the present investigation, the radon emanated from slate stone samples collected from different slate mines in Aravali range of hills in the Haryana state of Northern India has been estimated. For the measurement of radon concentration emanated from these samples, alpha-sensitive LR-115 type II plastic track detectors have been used. The alpha particles emitted from the radon form tracks in these detectors. After chemical etching the track density of registered tracks is used to calculate radon concentration and exhalation rates of radon using required formulae. The measurements indicate normal to some higher levels of radon concentration emanated from the slat stone samples collected from Aravali range of hills in north India. The results will be discussed in full paper. (author)

Development of a Soundproof Device for 950 Watt rated Portable ...

African Journals Online (AJOL)

The noise emanating from generators has adverse effects on our health. In view of this, this paper reports the development of soundproof device for 950Watt rated generators which are widely used portable generators. Performance evaluation of the soundproof device was carried out, and the sound pressure level of the ...

Maximum power point tracking

International Nuclear Information System (INIS)

Enslin, J.H.R.

1990-01-01

A well engineered renewable remote energy system, utilizing the principal of Maximum Power Point Tracking can be m ore cost effective, has a higher reliability and can improve the quality of life in remote areas. This paper reports that a high-efficient power electronic converter, for converting the output voltage of a solar panel, or wind generator, to the required DC battery bus voltage has been realized. The converter is controlled to track the maximum power point of the input source under varying input and output parameters. Maximum power point tracking for relative small systems is achieved by maximization of the output current in a battery charging regulator, using an optimized hill-climbing, inexpensive microprocessor based algorithm. Through practical field measurements it is shown that a minimum input source saving of 15% on 3-5 kWh/day systems can easily be achieved. A total cost saving of at least 10-15% on the capital cost of these systems are achievable for relative small rating Remote Area Power Supply systems. The advantages at larger temperature variations and larger power rated systems are much higher. Other advantages include optimal sizing and system monitor and control

Radon and thoron emanation from various marble materials: impact on the workers

International Nuclear Information System (INIS)

Misdaq, M.A.; Amghar, A.

2005-01-01

Uranium ( 238 U) and thorium ( 232 Th) concentrations were measured inside different pulverized marble material samples by using a method based on determining detection efficiencies of the CR-39 and LR-115 II solid state nuclear track detectors for the emitted alpha particles. Radon ( 222 Rn) and thoron ( 220 Rn) alpha-activities per unit volume were evaluated inside and outside the marble samples studied. Radon emanation coefficient was determined for the considered marble samples. Alpha- and beta-activities per unit volume of air due to radon, thoron and their progenies were measured in the atmosphere of a marble factory. Equilibrium factors between radon and its progeny and thoron and its decay products were evaluated in the air of the studied marble factory. The committed equivalent doses due to short-lived radon decay products were determined in different regions of the respiratory tract of workers in the considered marble factory

Improving Bayesian credibility intervals for classifier error rates using maximum entropy empirical priors.

Science.gov (United States)

Gustafsson, Mats G; Wallman, Mikael; Wickenberg Bolin, Ulrika; Göransson, Hanna; Fryknäs, M; Andersson, Claes R; Isaksson, Anders

2010-06-01

Successful use of classifiers that learn to make decisions from a set of patient examples require robust methods for performance estimation. Recently many promising approaches for determination of an upper bound for the error rate of a single classifier have been reported but the Bayesian credibility interval (CI) obtained from a conventional holdout test still delivers one of the tightest bounds. The conventional Bayesian CI becomes unacceptably large in real world applications where the test set sizes are less than a few hundred. The source of this problem is that fact that the CI is determined exclusively by the result on the test examples. In other words, there is no information at all provided by the uniform prior density distribution employed which reflects complete lack of prior knowledge about the unknown error rate. Therefore, the aim of the study reported here was to study a maximum entropy (ME) based approach to improved prior knowledge and Bayesian CIs, demonstrating its relevance for biomedical research and clinical practice. It is demonstrated how a refined non-uniform prior density distribution can be obtained by means of the ME principle using empirical results from a few designs and tests using non-overlapping sets of examples. Experimental results show that ME based priors improve the CIs when employed to four quite different simulated and two real world data sets. An empirically derived ME prior seems promising for improving the Bayesian CI for the unknown error rate of a designed classifier. Copyright 2010 Elsevier B.V. All rights reserved.

Formal comment on: Myhrvold (2016) Dinosaur metabolism and the allometry of maximum growth rate. PLoS ONE; 11(11): e0163205.

Science.gov (United States)

Griebeler, Eva Maria; Werner, Jan

2018-01-01

In his 2016 paper, Myhrvold criticized ours from 2014 on maximum growth rates (Gmax, maximum gain in body mass observed within a time unit throughout an individual's ontogeny) and thermoregulation strategies (ectothermy, endothermy) of 17 dinosaurs. In our paper, we showed that Gmax values of similar-sized extant ectothermic and endothermic vertebrates overlap. This strongly questions a correct assignment of a thermoregulation strategy to a dinosaur only based on its Gmax and (adult) body mass (M). Contrary, Gmax separated similar-sized extant reptiles and birds (Sauropsida) and Gmax values of our studied dinosaurs were similar to those seen in extant similar-sized (if necessary scaled-up) fast growing ectothermic reptiles. Myhrvold examined two hypotheses (H1 and H2) regarding our study. However, we did neither infer dinosaurian thermoregulation strategies from group-wide averages (H1) nor were our results based on that Gmax and metabolic rate (MR) are related (H2). In order to assess whether single dinosaurian Gmax values fit to those of extant endotherms (birds) or of ectotherms (reptiles), we already used a method suggested by Myhrvold to avoid H1, and we only discussed pros and cons of a relation between Gmax and MR and did not apply it (H2). We appreciate Myhrvold's efforts in eliminating the correlation between Gmax and M in order to statistically improve vertebrate scaling regressions on maximum gain in body mass. However, we show here that his mass-specific maximum growth rate (kC) replacing Gmax (= MkC) does not model the expected higher mass gain in larger than in smaller species for any set of species. We also comment on, why we considered extant reptiles and birds as reference models for extinct dinosaurs and why we used phylogenetically-informed regression analysis throughout our study. Finally, we question several arguments given in Myhrvold in order to support his results.

Use of generator substitution to determine the real attenuation of informative signals in the compromising emanation

Directory of Open Access Journals (Sweden)

Alexander A. Golyakhov

2018-05-01

Full Text Available A determination of real attenuation of information signal's radiation on a way from the source to a possible location of intelligence devices is considered to be the most difficult operation while assessing information security against leakage of electromagnetic emanation. In this context the problem of automation of this kind of measurement is of great interest. It takes considerable effort and time to measure the attenuation by existing automated systems. That is why the measurements are generally taken within the limited range of frequencies only. Along with that, a spectre of a single information impulse has a leaf-structure and is solid on every frequency leaf. So electromagnetic field intensity attenuation measurement carried on the some preselected frequencies is not able to represent the complete attenuation characteristics. The measurements of attenuation in the whole informative signal spectre within the given frequency range requires a few thousand measurements, which makes the current method ineffective and time consuming. The relevant specialized automatized measurement systems of security verification has active protection system noise measurement mode, which can be used to measure the real attenuation. In this article a rather exact method of real attenuation of informative signal of video subsystem of electron-ray tube monitor measurement is described and confirmed in experiment. The measurements were made using specialized automatized system “Sigurd” and video subsystem informative signal noise generator. The described method allows a significant reduction of  the time needed for specialized investigations of security verification on electromagnetic emanation.

The power and robustness of maximum LOD score statistics.

Science.gov (United States)

Yoo, Y J; Mendell, N R

2008-07-01

The maximum LOD score statistic is extremely powerful for gene mapping when calculated using the correct genetic parameter value. When the mode of genetic transmission is unknown, the maximum of the LOD scores obtained using several genetic parameter values is reported. This latter statistic requires higher critical value than the maximum LOD score statistic calculated from a single genetic parameter value. In this paper, we compare the power of maximum LOD scores based on three fixed sets of genetic parameter values with the power of the LOD score obtained after maximizing over the entire range of genetic parameter values. We simulate family data under nine generating models. For generating models with non-zero phenocopy rates, LOD scores maximized over the entire range of genetic parameters yielded greater power than maximum LOD scores for fixed sets of parameter values with zero phenocopy rates. No maximum LOD score was consistently more powerful than the others for generating models with a zero phenocopy rate. The power loss of the LOD score maximized over the entire range of genetic parameters, relative to the maximum LOD score calculated using the correct genetic parameter value, appeared to be robust to the generating models.

Effects of adipose tissue distribution on maximum lipid oxidation rate during exercise in normal-weight women.

Science.gov (United States)

Isacco, L; Thivel, D; Duclos, M; Aucouturier, J; Boisseau, N

2014-06-01

Fat mass localization affects lipid metabolism differently at rest and during exercise in overweight and normal-weight subjects. The aim of this study was to investigate the impact of a low vs high ratio of abdominal to lower-body fat mass (index of adipose tissue distribution) on the exercise intensity (Lipox(max)) that elicits the maximum lipid oxidation rate in normal-weight women. Twenty-one normal-weight women (22.0 ± 0.6 years, 22.3 ± 0.1 kg.m(-2)) were separated into two groups of either a low or high abdominal to lower-body fat mass ratio [L-A/LB (n = 11) or H-A/LB (n = 10), respectively]. Lipox(max) and maximum lipid oxidation rate (MLOR) were determined during a submaximum incremental exercise test. Abdominal and lower-body fat mass were determined from DXA scans. The two groups did not differ in aerobic fitness, total fat mass, or total and localized fat-free mass. Lipox(max) and MLOR were significantly lower in H-A/LB vs L-A/LB women (43 ± 3% VO(2max) vs 54 ± 4% VO(2max), and 4.8 ± 0.6 mg min(-1)kg FFM(-1)vs 8.4 ± 0.9 mg min(-1)kg FFM(-1), respectively; P normal-weight women, a predominantly abdominal fat mass distribution compared with a predominantly peripheral fat mass distribution is associated with a lower capacity to maximize lipid oxidation during exercise, as evidenced by their lower Lipox(max) and MLOR. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

From Sakata model to Goldberg-Ne'eman quarks and Nambu QCD phenomenology and 'right' and 'wrong' experiments

International Nuclear Information System (INIS)

Lipkin, Harry J.

2007-01-01

The basic theoretical milestones were the Sakata SU(3) symmetry, the Goldberg-Ne'eman composite model with SU(3) triplets having baryon number (1/3) and the Nambu color gauge Lagrangian. The transition was led in right and wrong directions by experiments interpreted by phenomenology. A 'good' experiment on p-bar p annihilation at rest showed that the Sakata model predictions disagreed with experiment. A 'bad' experiment prevented the use of the Goldberg-Ne'eman triplet model to predict the existence and masses of the Ξ * and Ω - . More 'good' experiments revealed the existence and mass of the Ξ * and the Ω - and the absence of positive strangeness baryon resonances, thus confirming the 'tenfold way'. Further 'good experiments' revealed the existence of the vector meson nonet, SU(3) breaking with singlet-octet mixing and the suppression of the φ → ρπ decay. These led to the quark triplet model. The paradox of peculiar statistics then arose as the Δ ++ and Ω - contained three identical spin-1/2 fermions coupled symmetrically to spin (3/2). This led to color and the Nambu QCD. The book 'Lie Groups for Pedestrians' used the Sakata model with the name 'sakaton' for the pnΛ triplet to teach the algebra of SU(3) to particle physicists in the U.S. and Europe who knew no group theory. The Sakata model had a renaissance in hypernuclear physics in the 1970's. (author)

Estimation of effective dose from Rn emanating from 'the minus ion' effect wallpaper

International Nuclear Information System (INIS)

Yoshizawa, Y.; Minowa, H.; Morita-Murase, Y.; Furuta, E.

2006-01-01

We have examined the wall papers which declared 'the minus ion' effect to estimate external and internal exposure dose from them. Results of gamma-ray spectrometry revealed that they contain 0.03 to 0.35 Bq·g -1 of Th-series nuclides, 208 Tl, 212 Pb, 212 Bi and 228 Ac, and U-series one, 214 Pb. Distributions of radioactive nuclides in the samples were measured using an imaging plate and a FLA-2000 (Fuji Photo Film). The radiation doses from the printed side of the wall papers were 5 to 15 times higher than that of the back side. The 222 Rn concentrations emanating from the wall papers in a sealed container of 50 liter were measured using the PICO-RAD radon detectors. One wall paper showed two to five times higher than the background value. (author)

Reducing biting rates of Aedes aegypti with metofluthrin: investigations in time and space.

Science.gov (United States)

Darbro, Jonathan M; Muzari, M Odwell; Giblin, Arthur; Adamczyk, Rebecca M; Ritchie, Scott A; Devine, Gregor J

2017-02-07

Indoor residual spraying is key to dengue control in Cairns and other parts of northern Queensland, Australia, where Aedes aegypti is prevalent, but the strategy faces challenges with regards to slow application time and, therefore, community coverage. A faster potential improvement might be the use of polyethylene netting impregnated with the volatile pyrethroid metofluthrin (SumiOne™). This formulation was assessed in rooms in three houses in Cairns, Australia. One emanator was placed in each room and cages of 10 female Aedes aegypti were exposed at distances of 1 and 3 m. Knockdown and landings on a human hand were counted before metofluthrin exposure and at 10, 30, 60, 90 and 120 min during exposure. In addition, two trials continued over 48 h of exposure to assess the long-term sublethal effects of metofluthrin on caged mosquitoes. Percentage landing rates fell to 0-2.5% in the first 10 min of exposure. Knockdown was most evident between 10 and 30 min (54% at 1 m and 33% at 3 m). Distance from the emanator strongly affected the results: mosquitoes at 3 m exhibited less knockdown and more landings than those at 1 m. As room volume increased, knockdown decreased and the number of landing increased. There is a cumulative mortality and landing inhibition and, for mosquitoes exposed to metofluthrin for > 48 h, mortality was 100% at 1 m and 90% at 3 m. Of those still alive, a small number continued to land and bite. After being removed from metofluthrin-treated rooms, exposed insect cages were found to reducing landing rates for up to 2 h. Despite only moderate levels of knockdown during the initial hours of exposure, metofluthrin emanators were effective in reducing mosquito landing rates, especially within 1 m, even when exposed on an open veranda. The evaluation methods and results described in this paper will help inform the optimal conditions of deployment of metofluthrin emanators. These devices have the potential to reduce contact between

Radon exhalation rate and natural radionuclide content in building materials of high background areas of Ramsar, Iran.

Science.gov (United States)

Bavarnegin, E; Fathabadi, N; Vahabi Moghaddam, M; Vasheghani Farahani, M; Moradi, M; Babakhni, A

2013-03-01

Radon exhalation rates from building materials used in high background radiation areas (HBRA) of Ramsar were measured using an active radon gas analyzer with an emanation container. Radon exhalation rates from these samples varied from below the lower detection limit up to 384 Bq.m(-2) h(-1). The (226)Ra, (232)Th and (40)K contents were also measured using a high resolution HPGe gamma- ray spectrometer system. The activity concentration of (226)Ra, (232)Th and (40)K content varied from below the minimum detection limit up to 86,400 Bq kg(-1), 187 Bq kg(-1) and 1350 Bq kg(-1), respectively. The linear correlation coefficient between radon exhalation rate and radium concentration was 0.90. The result of this survey shows that radon exhalation rate and radium content in some local stones used as basements are extremely high and these samples are main sources of indoor radon emanation as well as external gamma radiation from uranium series. Copyright © 2012 Elsevier Ltd. All rights reserved.

Maximum Entropy in Drug Discovery

Directory of Open Access Journals (Sweden)

Chih-Yuan Tseng

2014-07-01

Full Text Available Drug discovery applies multidisciplinary approaches either experimentally, computationally or both ways to identify lead compounds to treat various diseases. While conventional approaches have yielded many US Food and Drug Administration (FDA-approved drugs, researchers continue investigating and designing better approaches to increase the success rate in the discovery process. In this article, we provide an overview of the current strategies and point out where and how the method of maximum entropy has been introduced in this area. The maximum entropy principle has its root in thermodynamics, yet since Jaynes’ pioneering work in the 1950s, the maximum entropy principle has not only been used as a physics law, but also as a reasoning tool that allows us to process information in hand with the least bias. Its applicability in various disciplines has been abundantly demonstrated. We give several examples of applications of maximum entropy in different stages of drug discovery. Finally, we discuss a promising new direction in drug discovery that is likely to hinge on the ways of utilizing maximum entropy.

The mechanics of granitoid systems and maximum entropy production rates.

Science.gov (United States)

Hobbs, Bruce E; Ord, Alison

2010-01-13

A model for the formation of granitoid systems is developed involving melt production spatially below a rising isotherm that defines melt initiation. Production of the melt volumes necessary to form granitoid complexes within 10(4)-10(7) years demands control of the isotherm velocity by melt advection. This velocity is one control on the melt flux generated spatially just above the melt isotherm, which is the control valve for the behaviour of the complete granitoid system. Melt transport occurs in conduits initiated as sheets or tubes comprising melt inclusions arising from Gurson-Tvergaard constitutive behaviour. Such conduits appear as leucosomes parallel to lineations and foliations, and ductile and brittle dykes. The melt flux generated at the melt isotherm controls the position of the melt solidus isotherm and hence the physical height of the Transport/Emplacement Zone. A conduit width-selection process, driven by changes in melt viscosity and constitutive behaviour, operates within the Transport Zone to progressively increase the width of apertures upwards. Melt can also be driven horizontally by gradients in topography; these horizontal fluxes can be similar in magnitude to vertical fluxes. Fluxes induced by deformation can compete with both buoyancy and topographic-driven flow over all length scales and results locally in transient 'ponds' of melt. Pluton emplacement is controlled by the transition in constitutive behaviour of the melt/magma from elastic-viscous at high temperatures to elastic-plastic-viscous approaching the melt solidus enabling finite thickness plutons to develop. The system involves coupled feedback processes that grow at the expense of heat supplied to the system and compete with melt advection. The result is that limits are placed on the size and time scale of the system. Optimal characteristics of the system coincide with a state of maximum entropy production rate. This journal is © 2010 The Royal Society

Modelling maximum canopy conductance and transpiration in ...

African Journals Online (AJOL)

There is much current interest in predicting the maximum amount of water that can be transpired by Eucalyptus trees. It is possible that industrial waste water may be applied as irrigation water to eucalypts and it is important to predict the maximum transpiration rates of these plantations in an attempt to dispose of this ...

A simulation study of Linsley's approach to infer elongation rate and fluctuations of the EAS maximum depth from muon arrival time distributions

International Nuclear Information System (INIS)

Badea, A.F.; Brancus, I.M.; Rebel, H.; Haungs, A.; Oehlschlaeger, J.; Zazyan, M.

1999-01-01

The average depth of the maximum X m of the EAS (Extensive Air Shower) development depends on the energy E 0 and the mass of the primary particle, and its dependence from the energy is traditionally expressed by the so-called elongation rate D e defined as change in the average depth of the maximum per decade of E 0 i.e. D e = dX m /dlog 10 E 0 . Invoking the superposition model approximation i.e. assuming that a heavy primary (A) has the same shower elongation rate like a proton, but scaled with energies E 0 /A, one can write X m = X init + D e log 10 (E 0 /A). In 1977 an indirect approach studying D e has been suggested by Linsley. This approach can be applied to shower parameters which do not depend explicitly on the energy of the primary particle, but do depend on the depth of observation X and on the depth X m of shower maximum. The distribution of the EAS muon arrival times, measured at a certain observation level relatively to the arrival time of the shower core reflect the pathlength distribution of the muon travel from locus of production (near the axis) to the observation locus. The basic a priori assumption is that we can associate the mean value or median T of the time distribution to the height of the EAS maximum X m , and that we can express T = f(X,X m ). In order to derive from the energy variation of the arrival time quantities information about elongation rate, some knowledge is required about F i.e. F = - ∂ T/∂X m ) X /∂(T/∂X) X m , in addition to the variations with the depth of observation and the zenith-angle (θ) dependence, respectively. Thus ∂T/∂log 10 E 0 | X = - F·D e ·1/X v ·∂T/∂secθ| E 0 . In a similar way the fluctuations σ(X m ) of X m may be related to the fluctuations σ(T) of T i.e. σ(T) = - σ(X m )· F σ ·1/X v ·∂T/∂secθ| E 0 , with F σ being the corresponding scaling factor for the fluctuation of F. By simulations of the EAS development using the Monte Carlo code CORSIKA the energy and angle

Scintillation camera for high activity sources

International Nuclear Information System (INIS)

Arseneau, R.E.

1976-01-01

A scintillation camera is provided with electrical components which expand the intrinsic maximum rate of acceptance for processing of pulses emanating from detected radioactive events. Buffer storage is provided to accommodate temporary increases in the level of radioactivity. An early provisional determination of acceptability of pulses allows many unacceptable pulses to be discarded at an early stage

Maximum type 1 error rate inflation in multiarmed clinical trials with adaptive interim sample size modifications.

Science.gov (United States)

Graf, Alexandra C; Bauer, Peter; Glimm, Ekkehard; Koenig, Franz

2014-07-01

Sample size modifications in the interim analyses of an adaptive design can inflate the type 1 error rate, if test statistics and critical boundaries are used in the final analysis as if no modification had been made. While this is already true for designs with an overall change of the sample size in a balanced treatment-control comparison, the inflation can be much larger if in addition a modification of allocation ratios is allowed as well. In this paper, we investigate adaptive designs with several treatment arms compared to a single common control group. Regarding modifications, we consider treatment arm selection as well as modifications of overall sample size and allocation ratios. The inflation is quantified for two approaches: a naive procedure that ignores not only all modifications, but also the multiplicity issue arising from the many-to-one comparison, and a Dunnett procedure that ignores modifications, but adjusts for the initially started multiple treatments. The maximum inflation of the type 1 error rate for such types of design can be calculated by searching for the "worst case" scenarios, that are sample size adaptation rules in the interim analysis that lead to the largest conditional type 1 error rate in any point of the sample space. To show the most extreme inflation, we initially assume unconstrained second stage sample size modifications leading to a large inflation of the type 1 error rate. Furthermore, we investigate the inflation when putting constraints on the second stage sample sizes. It turns out that, for example fixing the sample size of the control group, leads to designs controlling the type 1 error rate. © 2014 The Author. Biometrical Journal published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Quantitative aspects of highly emanating geologic materials and their role in creating high indoor radon. Final report, April 1, 1994--March 31, 1996

International Nuclear Information System (INIS)

Gundersen, L.C.S.; Schumann, R.R.; Gates, A.E.; Price, P.

1996-01-01

Indoor radon hot spots, areas where indoor radon commonly exceeds 20 pCi/L, are often caused by unusually highly emanating soils or rock and their interaction with ambient climatic conditions and a building's architecture. Highly emanating soils and rocks include glacial deposits; dry fractured clays; black shales; limestone-derived soils; karst and cave areas, fractured or sheared granitic crystalline rocks; mine tailings; uraniferous backfill; and most uranium deposits. The above list probably accounts for 90% of the Nation's indoor radon over 20 pCi/L. In several of these high indoor radon areas, there appears to be a link between the nature of the radon source in the ground, the architecture of the home, and the relative magnitude and ease of mitigation of the indoor air problem. Quantification of geologic materials in terms of their radon potential with respect to climatic and architectural considerations has never been accomplished. Recent studies have attempted semi-quantitative rankings but rigorous analysis has not been done. In this investigation the authors have attempted to develop the quantitative aspects of geologic materials for prediction of very high indoor radon at several scales of observation from national to census tract

Releasable activity and maximum permissible leakage rate within a transport cask of Tehran Research Reactor fuel samples

Directory of Open Access Journals (Sweden)

Rezaeian Mahdi

2015-01-01

Full Text Available Containment of a transport cask during both normal and accident conditions is important to the health and safety of the public and of the operators. Based on IAEA regulations, releasable activity and maximum permissible volumetric leakage rate within the cask containing fuel samples of Tehran Research Reactor enclosed in an irradiated capsule are calculated. The contributions to the total activity from the four sources of gas, volatile, fines, and corrosion products are treated separately. These calculations are necessary to identify an appropriate leak test that must be performed on the cask and the results can be utilized as the source term for dose evaluation in the safety assessment of the cask.

Maximum Evaporation Rates of Water Droplets Approaching Obstacles in the Atmosphere Under Icing Conditions

Science.gov (United States)

Lowell, H. H.

1953-01-01

When a closed body or a duct envelope moves through the atmosphere, air pressure and temperature rises occur ahead of the body or, under ram conditions, within the duct. If cloud water droplets are encountered, droplet evaporation will result because of the air-temperature rise and the relative velocity between the droplet and stagnating air. It is shown that the solution of the steady-state psychrometric equation provides evaporation rates which are the maximum possible when droplets are entrained in air moving along stagnation lines under such conditions. Calculations are made for a wide variety of water droplet diameters, ambient conditions, and flight Mach numbers. Droplet diameter, body size, and Mach number effects are found to predominate, whereas wide variation in ambient conditions are of relatively small significance in the determination of evaporation rates. The results are essentially exact for the case of movement of droplets having diameters smaller than about 30 microns along relatively long ducts (length at least several feet) or toward large obstacles (wings), since disequilibrium effects are then of little significance. Mass losses in the case of movement within ducts will often be significant fractions (one-fifth to one-half) of original droplet masses, while very small droplets within ducts will often disappear even though the entraining air is not fully stagnated. Wing-approach evaporation losses will usually be of the order of several percent of original droplet masses. Two numerical examples are given of the determination of local evaporation rates and total mass losses in cases involving cloud droplets approaching circular cylinders along stagnation lines. The cylinders chosen were of 3.95-inch (10.0+ cm) diameter and 39.5-inch 100+ cm) diameter. The smaller is representative of icing-rate measurement cylinders, while with the larger will be associated an air-flow field similar to that ahead of an airfoil having a leading-edge radius

78 FR 13999 - Maximum Interest Rates on Guaranteed Farm Loans

Science.gov (United States)

2013-03-04

..., cost-plus, flat-rate, or market based) to price guaranteed loans, provided the rates do not exceed the... (LIBOR) or the 5-year Treasury note rate, unless the lender uses a formal written risk-based pricing... cost in the form of a lower interest rate than the borrower would otherwise receive. Therefore, the FSA...

Estimation of the players maximum heart rate in real game situations in team sports: a practical propose

Directory of Open Access Journals (Sweden)

Jorge Cuadrado Reyes

2011-05-01

Full Text Available Abstract   This  research developed a logarithms  for calculating the maximum heart rate (max. HR for players in team sports in  game situations. The sample was made of  thirteen players (aged 24 ± 3   to a  Division Two Handball team. HR was initially measured by Course Navette test.  Later, twenty one training sessions were conducted  in which HR and Rate of Perceived Exertion (RPE, were  continuously monitored, in each task. A lineal regression analysis was done  to help find a max. HR prediction equation from the max. HR of the three highest intensity sessions. Results from  this equation correlate significantly with data obtained in the Course Navette test and with those obtained by other indirect methods. The conclusion of this research is that this equation provides a very useful and easy way to measure the max. HR in real game situations, avoiding non-specific analytical tests and, therefore laboratory testing..   Key words: workout control, functional evaluation, prediction equation.

On the Five-Moment Hamburger Maximum Entropy Reconstruction

Science.gov (United States)

Summy, D. P.; Pullin, D. I.

2018-05-01

We consider the Maximum Entropy Reconstruction (MER) as a solution to the five-moment truncated Hamburger moment problem in one dimension. In the case of five monomial moment constraints, the probability density function (PDF) of the MER takes the form of the exponential of a quartic polynomial. This implies a possible bimodal structure in regions of moment space. An analytical model is developed for the MER PDF applicable near a known singular line in a centered, two-component, third- and fourth-order moment (μ _3 , μ _4 ) space, consistent with the general problem of five moments. The model consists of the superposition of a perturbed, centered Gaussian PDF and a small-amplitude packet of PDF-density, called the outlying moment packet (OMP), sitting far from the mean. Asymptotic solutions are obtained which predict the shape of the perturbed Gaussian and both the amplitude and position on the real line of the OMP. The asymptotic solutions show that the presence of the OMP gives rise to an MER solution that is singular along a line in (μ _3 , μ _4 ) space emanating from, but not including, the point representing a standard normal distribution, or thermodynamic equilibrium. We use this analysis of the OMP to develop a numerical regularization of the MER, creating a procedure we call the Hybrid MER (HMER). Compared with the MER, the HMER is a significant improvement in terms of robustness and efficiency while preserving accuracy in its prediction of other important distribution features, such as higher order moments.

Radon exhalation rates from soil and sand samples collected from the vicinity of Yamuna river

International Nuclear Information System (INIS)

Garg, A.K.; Sushil Kumar; Chauhan, Pooja; Chauhan, R.P.

2011-01-01

Soil, sand and stones are the most popular building materials for Indian dwellings. Radon is released into ambient air from these materials due to ubiquitous uranium and radium in them, thus increasing the airborne radon concentration. The radioactivity in sand and soils is related to radioactivity in the rocks from which they are formed. These materials contain varying amount of uranium. In the present investigation, the radon emanated from soil and sand samples from different locations in the vicinity of Yamuna river has been estimated. The samples have been collected from different locations near the Yamuna river. The samples collecting sites are from Yamunanagar in Haryana to Delhi. The radon concentration in different samples has been calculated, based upon the data, the mass and the surface exhalation rates of radon emanated from them have also been calculated

A theoretical and experimental EPFM study of cracks emanating from a hole

International Nuclear Information System (INIS)

Broekhoven, M.J.G.

1978-01-01

Results are presented of a combined theoretical and experimental study on the onset of crack extension in the EPFM regime for through cracks emanating from a circular hole in a plate under tensile load, with emphasis on the applicability of the J-concept for predicting such extensions. This configuration was selected both because of its general importance and as a first approximation for a nozzle-to-vessel geometry. Theoretical investigations consisted of elastic-plastic finite element computations both for 3-point bend specimens and for plate geometry. J values were calculated using the contour-integral definition for J, and by the method of virtual crack extension. The applicability of simplified analytical approximations for J was also investigated. COD data were derived from finite element computed displacements. Experimental investigations included Jsub(Ic) tests on a series of bend specimens and crack extensions tests on a series of cracked perforated plate models. For practical reasons aluminium 2024-T 351 was selected as a suitable model material within the aims of the study. Onset of crack extension was determined by the heat-tinting procedure throughout the experiments, in some cases supplemented by fractographic investigations. The various theoretical solutions and experimental observations were compared and a number of conclusions were drawn. (author)

Petroleum production at Maximum Efficient Rate Naval Petroleum Reserve No. 1 (Elk Hills), Kern County, California

International Nuclear Information System (INIS)

1993-07-01

This document provides an analysis of the potential impacts associated with the proposed action, which is continued operation of Naval Petroleum Reserve No. I (NPR-1) at the Maximum Efficient Rate (MER) as authorized by Public law 94-258, the Naval Petroleum Reserves Production Act of 1976 (Act). The document also provides a similar analysis of alternatives to the proposed action, which also involve continued operations, but under lower development scenarios and lower rates of production. NPR-1 is a large oil and gas field jointly owned and operated by the federal government and Chevron U.SA Inc. (CUSA) pursuant to a Unit Plan Contract that became effective in 1944; the government's interest is approximately 78% and CUSA's interest is approximately 22%. The government's interest is under the jurisdiction of the United States Department of Energy (DOE). The facility is approximately 17,409 acres (74 square miles), and it is located in Kern County, California, about 25 miles southwest of Bakersfield and 100 miles north of Los Angeles in the south central portion of the state. The environmental analysis presented herein is a supplement to the NPR-1 Final Environmental Impact Statement of that was issued by DOE in 1979 (1979 EIS). As such, this document is a Supplemental Environmental Impact Statement (SEIS)

Radiofrequency Ablation of an Atrial Tachycardia Emanating From the Non-coronary Aortic Cusp Guided by an Electroanatomic Navigation System

Directory of Open Access Journals (Sweden)

Agustin Bortone

2010-02-01

Full Text Available We report on an atrial tachycardia (AT, emanating from the non-coronary (NC aortic cusp, ablated with the aid of an electro-anatomical navigation system. In this setting, the electrocardiographic, electrophysiologic (EP, anatomical, and ablative considerations are discussed.Although NC aortic cusp focal ATs are an uncommon EP finding, their ablation is effective and safe, especially from an atrio-ventricular (AV conductive point of view. This origin of AT must be invoked and systematically disclosed when a peri-AV nodal AT origin is suspected, in order to avoid a potentially harmful energy application at the vicinity of the AV conductive tissue.

An assessment on the recycling opportunities of wastes emanating from scrap metal processing in Mauritius

Energy Technology Data Exchange (ETDEWEB)

Mauthoor, Sumayya, E-mail: sumayya.mauthoor@umail.uom.ac.mu [Department of Chemical and Environmental Engineering, University of Mauritius, Réduit (Mauritius); Mohee, Romeela [Professor of Chemical and Environmental Engineering, National Research Chair in Solid Waste Management, Mauritius Research Council (Mauritius); Kowlesser, Prakash [Solid Waste/Beach Management Unit, Ministry of Local Government and Outer Islands (Mauritius)

2014-10-15

Highlights: • Scrap metal processing wastes. • Areas of applications for slag, electric arc furnace dust, mill scale and wastewater sludge. • Waste generation factor of 349.3 kg per ton of steel produced. • Waste management model. - Abstract: This paper presents an assessment on the wastes namely slag, dust, mill scale and sludge resulting from scrap metal processing. The aim of this study is to demonstrate that there are various ways via which scrap metal processing wastes can be reused or recycled in other applications instead of simply diverting them to the landfill. These wastes are briefly described and an overview on the different areas of applications is presented. Based on the results obtained, the waste generation factor developed was 349.3 kg per ton of steel produced and it was reported that slag represents 72% of the total wastes emanating from the iron and steel industry in Mauritius. Finally the suitability of the different treatment and valorisation options in the context of Mauritius is examined.

The human volatilome: volatile organic compounds (VOCs) in exhaled breath, skin emanations, urine, feces and saliva.

Science.gov (United States)

Amann, Anton; Costello, Ben de Lacy; Miekisch, Wolfram; Schubert, Jochen; Buszewski, Bogusław; Pleil, Joachim; Ratcliffe, Norman; Risby, Terence

2014-09-01

Breath analysis is a young field of research with its roots in antiquity. Antoine Lavoisier discovered carbon dioxide in exhaled breath during the period 1777-1783, Wilhelm (Vilém) Petters discovered acetone in breath in 1857 and Johannes Müller reported the first quantitative measurements of acetone in 1898. A recent review reported 1765 volatile compounds appearing in exhaled breath, skin emanations, urine, saliva, human breast milk, blood and feces. For a large number of compounds, real-time analysis of exhaled breath or skin emanations has been performed, e.g., during exertion of effort on a stationary bicycle or during sleep. Volatile compounds in exhaled breath, which record historical exposure, are called the 'exposome'. Changes in biogenic volatile organic compound concentrations can be used to mirror metabolic or (patho)physiological processes in the whole body or blood concentrations of drugs (e.g. propofol) in clinical settings-even during artificial ventilation or during surgery. Also compounds released by bacterial strains like Pseudomonas aeruginosa or Streptococcus pneumonia could be very interesting. Methyl methacrylate (CAS 80-62-6), for example, was observed in the headspace of Streptococcus pneumonia in concentrations up to 1420 ppb. Fecal volatiles have been implicated in differentiating certain infectious bowel diseases such as Clostridium difficile, Campylobacter, Salmonella and Cholera. They have also been used to differentiate other non-infectious conditions such as irritable bowel syndrome and inflammatory bowel disease. In addition, alterations in urine volatiles have been used to detect urinary tract infections, bladder, prostate and other cancers. Peroxidation of lipids and other biomolecules by reactive oxygen species produce volatile compounds like ethane and 1-pentane. Noninvasive detection and therapeutic monitoring of oxidative stress would be highly desirable in autoimmunological, neurological, inflammatory diseases and cancer

Should measurement of maximum urinary flow rate and residual urine volume be a part of a "minimal care" assessment programme in female incontinence?

DEFF Research Database (Denmark)

Sander, Pia; Mouritsen, L; Andersen, J Thorup

2002-01-01

OBJECTIVE: The aim of this study was to evaluate the value of routine measurements of urinary flow rate and residual urine volume as a part of a "minimal care" assessment programme for women with urinary incontinence in detecting clinical significant bladder emptying problems. MATERIAL AND METHODS....... Twenty-six per cent had a maximum flow rate less than 15 ml/s, but only 4% at a voided volume > or =200 ml. Residual urine more than 149 ml was found in 6%. Two women had chronic retention with overflow incontinence. Both had typical symptoms with continuous leakage, stranguria and chronic cystitis...

TU-FG-209-03: Exploring the Maximum Count Rate Capabilities of Photon Counting Arrays Based On Polycrystalline Silicon

Energy Technology Data Exchange (ETDEWEB)

Liang, A K; Koniczek, M; Antonuk, L E; El-Mohri, Y; Zhao, Q [University of Michigan, Ann Arbor, MI (United States)

2016-06-15

Purpose: Photon counting arrays (PCAs) offer several advantages over conventional, fluence-integrating x-ray imagers, such as improved contrast by means of energy windowing. For that reason, we are exploring the feasibility and performance of PCA pixel circuitry based on polycrystalline silicon. This material, unlike the crystalline silicon commonly used in photon counting detectors, lends itself toward the economic manufacture of radiation tolerant, monolithic large area (e.g., ∼43×43 cm2) devices. In this presentation, exploration of maximum count rate, a critical performance parameter for such devices, is reported. Methods: Count rate performance for a variety of pixel circuit designs was explored through detailed circuit simulations over a wide range of parameters (including pixel pitch and operating conditions) with the additional goal of preserving good energy resolution. The count rate simulations assume input events corresponding to a 72 kVp x-ray spectrum with 20 mm Al filtration interacting with a CZT detector at various input flux rates. Output count rates are determined at various photon energy threshold levels, and the percentage of counts lost (e.g., due to deadtime or pile-up) is calculated from the ratio of output to input counts. The energy resolution simulations involve thermal and flicker noise originating from each circuit element in a design. Results: Circuit designs compatible with pixel pitches ranging from 250 to 1000 µm that allow count rates over a megacount per second per pixel appear feasible. Such rates are expected to be suitable for radiographic and fluoroscopic imaging. Results for the analog front-end circuitry of the pixels show that acceptable energy resolution can also be achieved. Conclusion: PCAs created using polycrystalline silicon have the potential to offer monolithic large-area detectors with count rate performance comparable to those of crystalline silicon detectors. Further improvement through detailed circuit

The tropical lapse rate steepened during the Last Glacial Maximum

NARCIS (Netherlands)

Loomis, S.E.; Russell, J.M.; Verschuren, D.; Morrill, C.; De Cort, G.; Sinninghe Damsté, J.S.; Olago, D.; Eggermont, H.; Street-Perrott, F.A.; Kelly, M.A.

2017-01-01

The gradient of air temperature with elevation (the temperature lapse rate) in the tropics is predicted to become lesssteep during the coming century as surface temperature rises, enhancing the threat of warming in high-mountainenvironments. However, the sensitivity of the lapse rate to climate

Finite mixture model: A maximum likelihood estimation approach on time series data

Science.gov (United States)

Yen, Phoong Seuk; Ismail, Mohd Tahir; Hamzah, Firdaus Mohamad

2014-09-01

Recently, statistician emphasized on the fitting of finite mixture model by using maximum likelihood estimation as it provides asymptotic properties. In addition, it shows consistency properties as the sample sizes increases to infinity. This illustrated that maximum likelihood estimation is an unbiased estimator. Moreover, the estimate parameters obtained from the application of maximum likelihood estimation have smallest variance as compared to others statistical method as the sample sizes increases. Thus, maximum likelihood estimation is adopted in this paper to fit the two-component mixture model in order to explore the relationship between rubber price and exchange rate for Malaysia, Thailand, Philippines and Indonesia. Results described that there is a negative effect among rubber price and exchange rate for all selected countries.

Natural radioactivity and radon specific exhalation rate of zircon sands

International Nuclear Information System (INIS)

Righi, S.; Verita, S.; Bruzzi, L.; Albertazzi, A.

2006-01-01

The study focuses on the radon emanation from zircon sands and their derivatives, which are widely used in many sectors of industry. In particular, the results obtained by experimental measurements on samples of zircon sands and zircon flours commonly used in Italian ceramic industries are reported. Zircon sands contain a significant concentration of natural radioactivity because Th and U may substitute zirconium in the zircon crystal lattice. The relevant routes of exposure of workers to T.E.N.O.R.M. from zircon materials are external radiation and internal exposure, either by inhalation of aerosols in dusty working conditions or by inhalation of radon in workplaces. The main objective of this investigation is to provide experimental data able to better calculate the internal exposure of workers due to radon inhalation. Zircon samples were surveyed for natural radioactivity, radon specific exhalation rate and emanation fraction. Measurements of radioactivity concentration were carried out using γ-spectrometry. Methods used for determining radon consisted in determining the 222 Rn activity accumulated in a vessel after a given accumulation build-up time. The average activity concentrations of 238 U and 232 Th in samples result about 2600 and 550 Bq kg-1, respectively; these concentrations are significantly higher than the world average noticed in soils, rocks and Earth crust. The 222 Rn specific exhalation rates result very low probably due to the low porosity of the material and the consequent difficulty for radon to be released from the zircon crystal lattice. (author)

The tropical lapse rate steepened during the Last Glacial Maximum

NARCIS (Netherlands)

Loomis, Shannon E; Russell, James M; Verschuren, Dirk; Morrill, Carrie; De Cort, Gijs; Sinninghe Damsté, Jaap S; Olago, Daniel; Eggermont, Hilde; Street-Perrott, F Alayne; Kelly, Meredith A

The gradient of air temperature with elevation (the temperature lapse rate) in the tropics is predicted to become less steep during the coming century as surface temperature rises, enhancing the threat of warming in high-mountain environments. However, the sensitivity of the lapse rate to climate

Investigation of the Maximum Spin-Up Coefficients of Friction Obtained During Tests of a Landing Gear Having a Static-Load Rating of 20,000 Pounds

Science.gov (United States)

Batterson, Sidney A.

1959-01-01

An experimental investigation was made at the Langley landing loads track to obtain data on the maximum spin-up coefficients of friction developed by a landing gear having a static-load rating of 20,000 pounds. The forward speeds ranged from 0 to approximately 180 feet per second and the sinking speeds, from 2.7 feet per second to 9.4 feet per second. The results indicated the variation of the maximum spin-up coefficient of friction with forward speed and vertical load. Data obtained during this investigation are also compared with some results previously obtained for nonrolling tires to show the effect of forward speed.

Test-Retest Reliability of Rating of Perceived Exertion and Agreement With 1-Repetition Maximum in Adults.

Science.gov (United States)

Bove, Allyn M; Lynch, Andrew D; DePaul, Samantha M; Terhorst, Lauren; Irrgang, James J; Fitzgerald, G Kelley

2016-09-01

Study Design Clinical measurement. Background It has been suggested that rating of perceived exertion (RPE) may be a useful alternative to 1-repetition maximum (1RM) to determine proper resistance exercise dosage. However, the test-retest reliability of RPE for resistance exercise has not been determined. Additionally, prior research regarding the relationship between 1RM and RPE is conflicting. Objectives The purpose of this study was to (1) determine test-retest reliability of RPE related to resistance exercise and (2) assess agreement between percentages of 1RM and RPE during quadriceps resistance exercise. Methods A sample of participants with and without knee pathology completed a series of knee extension exercises and rated the perceived difficulty of each exercise on a 0-to-10 RPE scale, then repeated the procedure 1 to 2 weeks later for test-retest reliability. To determine agreement between RPE and 1RM, participants completed knee extension exercises at various percentages of their 1RM (10% to 130% of predicted 1RM) and rated the perceived difficulty of each exercise on a 0-to-10 RPE scale. Percent agreement was calculated between the 1RM and RPE at each resistance interval. Results The intraclass correlation coefficient indicated excellent test-retest reliability of RPE for quadriceps resistance exercises (intraclass correlation coefficient = 0.895; 95% confidence interval: 0.866, 0.918). Overall percent agreement between RPE and 1RM was 60%, but agreement was poor within the ranges that would typically be used for training (50% 1RM for muscle endurance, 70% 1RM and greater for strength). Conclusion Test-retest reliability of perceived exertion during quadriceps resistance exercise was excellent. However, agreement between the RPE and 1RM was poor, especially in common training zones for knee extensor strengthening. J Orthop Sports Phys Ther 2016;46(9):768-774. Epub 5 Aug 2016. doi:10.2519/jospt.2016.6498.

To the elementary theory of critical (maximum) flow rate of two-phase mixture in channels with various sections

International Nuclear Information System (INIS)

Nigmatulin, B.I.; Soplenkov, K.I.

1978-01-01

On the basis of the concepts of two-phase dispersive flow with various structures (bubble, vapour-drop etc) in the framework of the two-speed and two-temperature one-dimension stationary model of the current with provision for phase transitions the conditions, under which a critical (maximum) flow rate of two-phase mixture is achieved during its outflowing from a channel with the pre-set geometry, have been determined. It is shown, that for the choosen set of two-phase flow equations with the known parameters of deceleration and structure one of the critical conditions is satisfied: either solution of the set of equations corresponding a critical flow rate is a special one, i.e. passes through a special point locating between minimum and outlet channel sections where the carrying phase velocity approaches the value of decelerated sound speed in the mixture or the determinator of the initial set of equations equals zero for the outlet channel sections, i.e. gradients of the main flow parameters tend to +-infinity in this section, and carrying phase velocity also approaches the value of the decelerated sound velocity in the mixture

Determination of radon exhalation rates from tiles using active and passive techniques

International Nuclear Information System (INIS)

Al-Jarallah, M.I.; Abu-Jarad, F.; Fazal-ur-Rehman

2001-01-01

Measurements of radon exhalation rates for selected samples of tiles used in Saudi Arabia were carried out using active and passive measuring techniques. These samples were granite, marble and ceramic. In the active method, a PC-based radon gas analyzer with emanation container was used, while, in the passive method, PM-355 nuclear track detectors with the 'can technique' were applied for 180 days. A comparison of the exhalation rates measured by the two techniques showed a good linear correlation coefficient of 0.7. The granite samples showed an average radon exhalation rate of 0.7 Bq m -2 h -1 , which was higher than that of marble and ceramic by more than twofold. The radon exhalation rates measured by the 'can technique' showed a non-uniform exhalation from the surface of the same tile

Impact of marine reserve on maximum sustainable yield in a traditional prey-predator system

Science.gov (United States)

Paul, Prosenjit; Kar, T. K.; Ghorai, Abhijit

2018-01-01

Multispecies fisheries management requires managers to consider the impact of fishing activities on several species as fishing impacts both targeted and non-targeted species directly or indirectly in several ways. The intended goal of traditional fisheries management is to achieve maximum sustainable yield (MSY) from the targeted species, which on many occasions affect the targeted species as well as the entire ecosystem. Marine reserves are often acclaimed as the marine ecosystem management tool. Few attempts have been made to generalize the ecological effects of marine reserve on MSY policy. We examine here how MSY and population level in a prey-predator system are affected by the low, medium and high reserve size under different possible scenarios. Our simulation works shows that low reserve area, the value of MSY for prey exploitation is maximum when both prey and predator species have fast movement rate. For medium reserve size, our analysis revealed that the maximum value of MSY for prey exploitation is obtained when prey population has fast movement rate and predator population has slow movement rate. For high reserve area, the maximum value of MSY for prey's exploitation is very low compared to the maximum value of MSY for prey's exploitation in case of low and medium reserve. On the other hand, for low and medium reserve area, MSY for predator exploitation is maximum when both the species have fast movement rate.

The maximum entropy production and maximum Shannon information entropy in enzyme kinetics

Science.gov (United States)

Dobovišek, Andrej; Markovič, Rene; Brumen, Milan; Fajmut, Aleš

2018-04-01

We demonstrate that the maximum entropy production principle (MEPP) serves as a physical selection principle for the description of the most probable non-equilibrium steady states in simple enzymatic reactions. A theoretical approach is developed, which enables maximization of the density of entropy production with respect to the enzyme rate constants for the enzyme reaction in a steady state. Mass and Gibbs free energy conservations are considered as optimization constraints. In such a way computed optimal enzyme rate constants in a steady state yield also the most uniform probability distribution of the enzyme states. This accounts for the maximal Shannon information entropy. By means of the stability analysis it is also demonstrated that maximal density of entropy production in that enzyme reaction requires flexible enzyme structure, which enables rapid transitions between different enzyme states. These results are supported by an example, in which density of entropy production and Shannon information entropy are numerically maximized for the enzyme Glucose Isomerase.

Rare-gas yields in 238U and 232Th fission by 14MeV neutrons, measured by an emanating method

International Nuclear Information System (INIS)

Feu Alvim, C.A.; Bocquet, J.P.; Brissot, R.; Crancon, J.; Moussa, A.

1977-01-01

A direct method, using emanation of rare gases by uranyle stearate and thorium stearate, has been applied to the measurement of cumulative fractional yields of certain isotopes of krypton and xenon, in the fissions of 238 U and 232 Th by 14MeV-neutrons. The independent yields of the same isotopes were measured previously by means of isotopic on-line separation. From these results, the widths of the mass and charge distributions, the relative chain yields, the fractional cumulative yields of certain bromine and iodine isotopes, the values of Zsub(p) the most probable charge, in the isobaric chains 87-93 and 137-142, and the elemental yields of krypton and xenon were calculated [fr

Radon exhalation rate and natural radionuclide content in building materials of high background areas of Ramsar, Iran

International Nuclear Information System (INIS)

Bavarnegin, E.; Fathabadi, N.; Vahabi Moghaddam, M.; Vasheghani Farahani, M.; Moradi, M.; Babakhni, A.

2013-01-01

Radon exhalation rates from building materials used in high background radiation areas (HBRA) of Ramsar were measured using an active radon gas analyzer with an emanation container. Radon exhalation rates from these samples varied from below the lower detection limit up to 384 Bq.m −2 h −1 . The 226 Ra, 232 Th and 40 K contents were also measured using a high resolution HPGe gamma- ray spectrometer system. The activity concentration of 226 Ra, 232 Th and 40 K content varied from below the minimum detection limit up to 86,400 Bq kg −1 , 187 Bq kg −1 and 1350 Bq kg −1 , respectively. The linear correlation coefficient between radon exhalation rate and radium concentration was 0.90. The result of this survey shows that radon exhalation rate and radium content in some local stones used as basements are extremely high and these samples are main sources of indoor radon emanation as well as external gamma radiation from uranium series. -- Highlights: ► In the selection process of local samples, portable scintillometer (NaI) was used. ► The activity concentration of 226 Ra varied from below the MDL up to 86400 Bq kg −1 . ► The activity concentration of 232 Th varied from below the MDL up to 187 Bq kg −1 . ► The activity concentration of 40 K varied from below the MDL up to 1350 Bq kg −1

Maximum-Entropy Inference with a Programmable Annealer

Science.gov (United States)

Chancellor, Nicholas; Szoke, Szilard; Vinci, Walter; Aeppli, Gabriel; Warburton, Paul A.

2016-03-01

Optimisation problems typically involve finding the ground state (i.e. the minimum energy configuration) of a cost function with respect to many variables. If the variables are corrupted by noise then this maximises the likelihood that the solution is correct. The maximum entropy solution on the other hand takes the form of a Boltzmann distribution over the ground and excited states of the cost function to correct for noise. Here we use a programmable annealer for the information decoding problem which we simulate as a random Ising model in a field. We show experimentally that finite temperature maximum entropy decoding can give slightly better bit-error-rates than the maximum likelihood approach, confirming that useful information can be extracted from the excited states of the annealer. Furthermore we introduce a bit-by-bit analytical method which is agnostic to the specific application and use it to show that the annealer samples from a highly Boltzmann-like distribution. Machines of this kind are therefore candidates for use in a variety of machine learning applications which exploit maximum entropy inference, including language processing and image recognition.

Adaptive transition rates in excitable membranes

Directory of Open Access Journals (Sweden)

Shimon Marom

2009-02-01

Full Text Available Adaptation of activity in excitable membranes occurs over a wide range of timescales. Standard computational approaches handle this wide temporal range in terms of multiple states and related reaction rates emanating from the complexity of ionic channels. The study described here takes a different (perhaps complementary approach, by interpreting ion channel kinetics in terms of population dynamics. I show that adaptation in excitable membranes is reducible to a simple Logistic-like equation in which the essential non-linearity is replaced by a feedback loop between the history of activation and an adaptive transition rate that is sensitive to a single dimension of the space of inactive states. This physiologically measurable dimension contributes to the stability of the system and serves as a powerful modulator of input-output relations that depends on the patterns of prior activity; an intrinsic scale free mechanism for cellular adaptation that emerges from the microscopic biophysical properties of ion channels of excitable membranes.

Maximum Smoke Temperature in Non-Smoke Model Evacuation Region for Semi-Transverse Tunnel Fire

OpenAIRE

B. Lou; Y. Qiu; X. Long

2017-01-01

Smoke temperature distribution in non-smoke evacuation under different mechanical smoke exhaust rates of semi-transverse tunnel fire were studied by FDS numerical simulation in this paper. The effect of fire heat release rate (10MW 20MW and 30MW) and exhaust rate (from 0 to 160m3/s) on the maximum smoke temperature in non-smoke evacuation region was discussed. Results show that the maximum smoke temperature in non-smoke evacuation region decreased with smoke exhaust rate. Plug-holing was obse...

Maximum Aerobic Capacity of Underground Coal Miners in India

Directory of Open Access Journals (Sweden)

Ratnadeep Saha

2011-01-01

Full Text Available Miners fitness test was assessed in terms of determination of maximum aerobic capacity by an indirect method following a standard step test protocol before going down to mine by taking into consideration of heart rates (Telemetric recording and oxygen consumption of the subjects (Oxylog-II during exercise at different working rates. Maximal heart rate was derived as 220−age. Coal miners reported a maximum aerobic capacity within a range of 35–38.3 mL/kg/min. It also revealed that oldest miners (50–59 yrs had a lowest maximal oxygen uptake (34.2±3.38 mL/kg/min compared to (42.4±2.03 mL/kg/min compared to (42.4±2.03 mL/kg/min the youngest group (20–29 yrs. It was found to be negatively correlated with age (r=−0.55 and −0.33 for younger and older groups respectively and directly associated with the body weight of the subjects (r=0.57 – 0.68, P≤0.001. Carriers showed maximum cardio respiratory capacity compared to other miners. Indian miners VO2max was found to be lower both compared to their abroad mining counterparts and various other non-mining occupational working groups in India.

Growth and maximum size of tiger sharks (Galeocerdo cuvier) in Hawaii.

Science.gov (United States)

Meyer, Carl G; O'Malley, Joseph M; Papastamatiou, Yannis P; Dale, Jonathan J; Hutchinson, Melanie R; Anderson, James M; Royer, Mark A; Holland, Kim N

2014-01-01

Tiger sharks (Galecerdo cuvier) are apex predators characterized by their broad diet, large size and rapid growth. Tiger shark maximum size is typically between 380 & 450 cm Total Length (TL), with a few individuals reaching 550 cm TL, but the maximum size of tiger sharks in Hawaii waters remains uncertain. A previous study suggested tiger sharks grow rather slowly in Hawaii compared to other regions, but this may have been an artifact of the method used to estimate growth (unvalidated vertebral ring counts) compounded by small sample size and narrow size range. Since 1993, the University of Hawaii has conducted a research program aimed at elucidating tiger shark biology, and to date 420 tiger sharks have been tagged and 50 recaptured. All recaptures were from Hawaii except a single shark recaptured off Isla Jacques Cousteau (24°13'17″N 109°52'14″W), in the southern Gulf of California (minimum distance between tag and recapture sites  =  approximately 5,000 km), after 366 days at liberty (DAL). We used these empirical mark-recapture data to estimate growth rates and maximum size for tiger sharks in Hawaii. We found that tiger sharks in Hawaii grow twice as fast as previously thought, on average reaching 340 cm TL by age 5, and attaining a maximum size of 403 cm TL. Our model indicates the fastest growing individuals attain 400 cm TL by age 5, and the largest reach a maximum size of 444 cm TL. The largest shark captured during our study was 464 cm TL but individuals >450 cm TL were extremely rare (0.005% of sharks captured). We conclude that tiger shark growth rates and maximum sizes in Hawaii are generally consistent with those in other regions, and hypothesize that a broad diet may help them to achieve this rapid growth by maximizing prey consumption rates.

Radon emanation rate as a function of monazite grain size

International Nuclear Information System (INIS)

Yogesan, S.; Stanley, J.D.; Rosli Mahat; Yusof Md Amin

1995-01-01

In this study, a sample of monazite from local mining area was divided to 7 parts according to size (μm) and each sample was analysed using silicon surface barrier detector and multichannel analyser. From this study it has found that small grain monazite produced more radon that big grain monazite and radium is distributed on or near the surface of the monazite grain

Characterization of the National Petroleum Reserve No. 3 (NPR-3) Site for Naturally Occurring Radioactive Material(NORM)

Energy Technology Data Exchange (ETDEWEB)

White, G.J; Rood, A.S.

1999-01-21

The National Petroleum Reserve No. 3 site (NPR-3) near Casper, Wyoming is being prepared for transfer to private industry. Remediation of the NPR-3 site has already begun in anticipation of this transfer. This document describes the characterization of the NPR-3 site for Naturally Occurring Radioactive Materials (NORM). Data generated on radionuclide concentrations and radon emanation may be used to determine disposal options and the need for remediation at this site. A preliminary gamma survey of the NPR-3 site was conducted to identify areas of potential NORM contamination. Based on these gamma surveys, two general areas of NORM contamination were found: the North Water Flood area and the BTP-10 produced water discharge steam. A maximum surface exposure rate of 120 {micro}R h{sup -1} was observed in the North Water Flood area, with the highest readings found along the drainage channel from the area. Exposure rates dropped to background quickly with increasing distance from the center of the drainage. The maximum observed exposure rate in the BTP-10 produced water drainage was 40 {micro}R h{sup -1}. Soil and sediment sampling were concentrated in these two areas. All samples were analyzed for concentration of {sup 226}Ra, {sup 228}Ra, and {sup 40}K. Maximum {sup 226}Ra concentrations observed in the samples collected were 46 pCi g{sup -1} for soil and 78 pCi g{sup -1} for sediment. Concentrations in most samples were considerably lower than these values. Radon emanation fraction was also measured for a randomly selected fraction of the samples. The mean Rn emanation fraction measured was 0.10, indicating that on average only 10 percent of the Rn produced is released from the medium. Based on the results of these analyses, NORM contamination at the NPR-3 site is minimal, and appears to be restricted to the two general areas sampled. Concentrations of NORM radionuclides found soils and sediments in these two locations do not justify remedial actions at present

Determination of radon exhalation rates from tiles using active and passive techniques

Energy Technology Data Exchange (ETDEWEB)

Al-Jarallah, M.I. E-mail: mibrahim@kfupm.edu.sa; Abu-Jarad, F.; Fazal-ur-Rehman

2001-06-01

Measurements of radon exhalation rates for selected samples of tiles used in Saudi Arabia were carried out using active and passive measuring techniques. These samples were granite, marble and ceramic. In the active method, a PC-based radon gas analyzer with emanation container was used, while, in the passive method, PM-355 nuclear track detectors with the 'can technique' were applied for 180 days. A comparison of the exhalation rates measured by the two techniques showed a good linear correlation coefficient of 0.7. The granite samples showed an average radon exhalation rate of 0.7 Bq m{sup -2} h{sup -1}, which was higher than that of marble and ceramic by more than twofold. The radon exhalation rates measured by the 'can technique' showed a non-uniform exhalation from the surface of the same tile.

Approximate maximum parsimony and ancestral maximum likelihood.

Science.gov (United States)

Alon, Noga; Chor, Benny; Pardi, Fabio; Rapoport, Anat

2010-01-01

We explore the maximum parsimony (MP) and ancestral maximum likelihood (AML) criteria in phylogenetic tree reconstruction. Both problems are NP-hard, so we seek approximate solutions. We formulate the two problems as Steiner tree problems under appropriate distances. The gist of our approach is the succinct characterization of Steiner trees for a small number of leaves for the two distances. This enables the use of known Steiner tree approximation algorithms. The approach leads to a 16/9 approximation ratio for AML and asymptotically to a 1.55 approximation ratio for MP.

ON THE MAXIMUM MASS OF STELLAR BLACK HOLES

International Nuclear Information System (INIS)

Belczynski, Krzysztof; Fryer, Chris L.; Bulik, Tomasz; Ruiter, Ashley; Valsecchi, Francesca; Vink, Jorick S.; Hurley, Jarrod R.

2010-01-01

We present the spectrum of compact object masses: neutron stars and black holes (BHs) that originate from single stars in different environments. In particular, we calculate the dependence of maximum BH mass on metallicity and on some specific wind mass loss rates (e.g., Hurley et al. and Vink et al.). Our calculations show that the highest mass BHs observed in the Galaxy M bh ∼ 15 M sun in the high metallicity environment (Z = Z sun = 0.02) can be explained with stellar models and the wind mass loss rates adopted here. To reach this result we had to set luminous blue variable mass loss rates at the level of ∼10 -4 M sun yr -1 and to employ metallicity-dependent Wolf-Rayet winds. With such winds, calibrated on Galactic BH mass measurements, the maximum BH mass obtained for moderate metallicity (Z = 0.3 Z sun = 0.006) is M bh,max = 30 M sun . This is a rather striking finding as the mass of the most massive known stellar BH is M bh = 23-34 M sun and, in fact, it is located in a small star-forming galaxy with moderate metallicity. We find that in the very low (globular cluster-like) metallicity environment the maximum BH mass can be as high as M bh,max = 80 M sun (Z = 0.01 Z sun = 0.0002). It is interesting to note that X-ray luminosity from Eddington-limited accretion onto an 80 M sun BH is of the order of ∼10 40 erg s -1 and is comparable to luminosities of some known ultra-luminous X-ray sources. We emphasize that our results were obtained for single stars only and that binary interactions may alter these maximum BH masses (e.g., accretion from a close companion). This is strictly a proof-of-principle study which demonstrates that stellar models can naturally explain even the most massive known stellar BHs.

n-Order and maximum fuzzy similarity entropy for discrimination of signals of different complexity: Application to fetal heart rate signals.

Science.gov (United States)

Zaylaa, Amira; Oudjemia, Souad; Charara, Jamal; Girault, Jean-Marc

2015-09-01

This paper presents two new concepts for discrimination of signals of different complexity. The first focused initially on solving the problem of setting entropy descriptors by varying the pattern size instead of the tolerance. This led to the search for the optimal pattern size that maximized the similarity entropy. The second paradigm was based on the n-order similarity entropy that encompasses the 1-order similarity entropy. To improve the statistical stability, n-order fuzzy similarity entropy was proposed. Fractional Brownian motion was simulated to validate the different methods proposed, and fetal heart rate signals were used to discriminate normal from abnormal fetuses. In all cases, it was found that it was possible to discriminate time series of different complexity such as fractional Brownian motion and fetal heart rate signals. The best levels of performance in terms of sensitivity (90%) and specificity (90%) were obtained with the n-order fuzzy similarity entropy. However, it was shown that the optimal pattern size and the maximum similarity measurement were related to intrinsic features of the time series. Copyright © 2015 Elsevier Ltd. All rights reserved.

A comparison of methods of predicting maximum oxygen uptake.

OpenAIRE

Grant, S; Corbett, K; Amjad, A M; Wilson, J; Aitchison, T

1995-01-01

The aim of this study was to compare the results from a Cooper walk run test, a multistage shuttle run test, and a submaximal cycle test with the direct measurement of maximum oxygen uptake on a treadmill. Three predictive tests of maximum oxygen uptake--linear extrapolation of heart rate of VO2 collected from a submaximal cycle ergometer test (predicted L/E), the Cooper 12 min walk, run test, and a multi-stage progressive shuttle run test (MST)--were performed by 22 young healthy males (mean...

Maximum Urine Flow Rate of Less than 15ml/Sec Increasing Risk of Urine Retention and Prostate Surgery among Patients with Alpha-1 Blockers: A 10-Year Follow Up Study.

Directory of Open Access Journals (Sweden)

Hsin-Ho Liu

Full Text Available The aim of this study was to determine the subsequent risk of acute urine retention and prostate surgery in patients receiving alpha-1 blockers treatment and having a maximum urinary flow rate of less than 15ml/sec.We identified patients who were diagnosed with benign prostate hyperplasia (BPH and had a maximum uroflow rate of less than 15ml/sec between 1 January, 2002 to 31 December, 2011 from Taiwan's National Health Insurance Research Database into study group (n = 303. The control cohort included four BPH/LUTS patients without 5ARI used for each study group, randomly selected from the same dataset (n = 1,212. Each patient was monitored to identify those who subsequently developed prostate surgery and acute urine retention.Prostate surgery and acute urine retention are detected in 5.9% of control group and 8.3% of study group during 10-year follow up. Compared with the control group, there was increase in the risk of prostate surgery and acute urine retention in the study group (HR = 1.83, 95% CI: 1.16 to 2.91 after adjusting for age, comorbidities, geographic region and socioeconomic status.Maximum urine flow rate of less than 15ml/sec is a risk factor of urinary retention and subsequent prostate surgery in BPH patients receiving alpha-1 blocker therapy. This result can provide a reference for clinicians.

ORIGINAL ARTICLES Surgical practice in a maximum security prison

African Journals Online (AJOL)

Prison Clinic, Mangaung Maximum Security Prison, Bloemfontein. F Kleinhans, BA (Cur) .... HIV positivity rate and the use of the rectum to store foreign objects. ... fruit in sunlight. Other positive health-promoting factors may also play a role,.

Information Entropy Production of Maximum Entropy Markov Chains from Spike Trains

Science.gov (United States)

Cofré, Rodrigo; Maldonado, Cesar

2018-01-01

We consider the maximum entropy Markov chain inference approach to characterize the collective statistics of neuronal spike trains, focusing on the statistical properties of the inferred model. We review large deviations techniques useful in this context to describe properties of accuracy and convergence in terms of sampling size. We use these results to study the statistical fluctuation of correlations, distinguishability and irreversibility of maximum entropy Markov chains. We illustrate these applications using simple examples where the large deviation rate function is explicitly obtained for maximum entropy models of relevance in this field.

Rating Movies and Rating the Raters Who Rate Them.

Science.gov (United States)

Zhou, Hua; Lange, Kenneth

2009-11-01

The movie distribution company Netflix has generated considerable buzz in the statistics community by offering a million dollar prize for improvements to its movie rating system. Among the statisticians and computer scientists who have disclosed their techniques, the emphasis has been on machine learning approaches. This article has the modest goal of discussing a simple model for movie rating and other forms of democratic rating. Because the model involves a large number of parameters, it is nontrivial to carry out maximum likelihood estimation. Here we derive a straightforward EM algorithm from the perspective of the more general MM algorithm. The algorithm is capable of finding the global maximum on a likelihood landscape littered with inferior modes. We apply two variants of the model to a dataset from the MovieLens archive and compare their results. Our model identifies quirky raters, redefines the raw rankings, and permits imputation of missing ratings. The model is intended to stimulate discussion and development of better theory rather than to win the prize. It has the added benefit of introducing readers to some of the issues connected with analyzing high-dimensional data.

Preparation of radionuclide {sup 212}Pb by emanation method and its subsequent application in radioindicator study of adsorption processes on the bentonite rocks; Priprava radionuklidu {sup 212}Pb emanacnou metodou a jeho nasledna aplikacia pri radioindikatorovom studiu adsorpcnych procesov na bentonitovych horninach

Energy Technology Data Exchange (ETDEWEB)

Viglasova, E; Rosskopfova, O; Galambos, M [Univerzita Komenskeho v Bratislave, Prirodovedecka fakulta, Katedra jadrovej chemie, 84215 Bratislava (Slovakia)

2012-04-25

The paper deals with the preparation of the radionuclide {sup 212}Pb by emanation and its further application in the study of adsorption processes in bentonite rocks. Chronic toxicity of Pb, as of one of the oldest contaminants, causes disturbances in reproductive behaviour, brain damage, neurological disorders, kidney activity damage and many others. {sup 212}Pb has radiogenic origin, it belongs to a series of {sup 232}Th and considering its short half-time time its occurrence is linked primarily to Th. Emanation is a suitable method for preparation of {sup 212}Pb, as a subsidiary radionuclide of a decay series of {sup 232}Th. Due to the electric field at a voltage of 310 V the {sup 212}Pb was captured from Th-source on niobium emanator sheets. Then it leached from there into HNO{sub 3} solution. After adjusting the pH solution and sample preparation there took place a radioindicator study of the effect of mixing time of solid and liquid phase on adsorption percentage of Pb. Adsorption of Pb was studied on bentonite from Slovakian deposits Lieskovec in relation to their use as a tightening barrier of different landfill sites. (authors)

Extracting volatility signal using maximum a posteriori estimation

Science.gov (United States)

Neto, David

2016-11-01

This paper outlines a methodology to estimate a denoised volatility signal for foreign exchange rates using a hidden Markov model (HMM). For this purpose a maximum a posteriori (MAP) estimation is performed. A double exponential prior is used for the state variable (the log-volatility) in order to allow sharp jumps in realizations and then log-returns marginal distributions with heavy tails. We consider two routes to choose the regularization and we compare our MAP estimate to realized volatility measure for three exchange rates.

Maximum permissible dose

International Nuclear Information System (INIS)

Anon.

1979-01-01

This chapter presents a historic overview of the establishment of radiation guidelines by various national and international agencies. The use of maximum permissible dose and maximum permissible body burden limits to derive working standards is discussed

Simultaneous and multi-point measurement of ammonia emanating from human skin surface for the estimation of whole body dermal emission rate.

Science.gov (United States)

Furukawa, Shota; Sekine, Yoshika; Kimura, Keita; Umezawa, Kazuo; Asai, Satomi; Miyachi, Hayato

2017-05-15

Ammonia is one of the members of odor gases and a possible source of odor in indoor environment. However, little has been known on the actual emission rate of ammonia from the human skin surface. Then, this study aimed to estimate the whole-body dermal emission rate of ammonia by simultaneous and multi-point measurement of emission fluxes of ammonia employing a passive flux sampler - ion chromatography system. Firstly, the emission fluxes of ammonia were non-invasively measured for ten volunteers at 13 sampling positions set in 13 anatomical regions classified by Kurazumi et al. The measured emission fluxes were then converted to partial emission rates using the surface body areas estimated by weights and heights of volunteers and partial rates of 13 body regions. Subsequent summation of the partial emission rates provided the whole body dermal emission rate of ammonia. The results ranged from 2.9 to 12mgh -1 with an average of 5.9±3.2mgh -1 per person for the ten healthy young volunteers. The values were much greater than those from human breath, and thus the dermal emission of ammonia was found more significant odor source than the breath exhalation in indoor environment. Copyright © 2017 Elsevier B.V. All rights reserved.

Hydraulic Limits on Maximum Plant Transpiration

Science.gov (United States)

Manzoni, S.; Vico, G.; Katul, G. G.; Palmroth, S.; Jackson, R. B.; Porporato, A. M.

2011-12-01

Photosynthesis occurs at the expense of water losses through transpiration. As a consequence of this basic carbon-water interaction at the leaf level, plant growth and ecosystem carbon exchanges are tightly coupled to transpiration. In this contribution, the hydraulic constraints that limit transpiration rates under well-watered conditions are examined across plant functional types and climates. The potential water flow through plants is proportional to both xylem hydraulic conductivity (which depends on plant carbon economy) and the difference in water potential between the soil and the atmosphere (the driving force that pulls water from the soil). Differently from previous works, we study how this potential flux changes with the amplitude of the driving force (i.e., we focus on xylem properties and not on stomatal regulation). Xylem hydraulic conductivity decreases as the driving force increases due to cavitation of the tissues. As a result of this negative feedback, more negative leaf (and xylem) water potentials would provide a stronger driving force for water transport, while at the same time limiting xylem hydraulic conductivity due to cavitation. Here, the leaf water potential value that allows an optimum balance between driving force and xylem conductivity is quantified, thus defining the maximum transpiration rate that can be sustained by the soil-to-leaf hydraulic system. To apply the proposed framework at the global scale, a novel database of xylem conductivity and cavitation vulnerability across plant types and biomes is developed. Conductivity and water potential at 50% cavitation are shown to be complementary (in particular between angiosperms and conifers), suggesting a tradeoff between transport efficiency and hydraulic safety. Plants from warmer and drier biomes tend to achieve larger maximum transpiration than plants growing in environments with lower atmospheric water demand. The predicted maximum transpiration and the corresponding leaf water

Maximum rates of climate change are systematically underestimated in the geological record.

Science.gov (United States)

Kemp, David B; Eichenseer, Kilian; Kiessling, Wolfgang

2015-11-10

Recently observed rates of environmental change are typically much higher than those inferred for the geological past. At the same time, the magnitudes of ancient changes were often substantially greater than those established in recent history. The most pertinent disparity, however, between recent and geological rates is the timespan over which the rates are measured, which typically differ by several orders of magnitude. Here we show that rates of marked temperature changes inferred from proxy data in Earth history scale with measurement timespan as an approximate power law across nearly six orders of magnitude (10(2) to >10(7) years). This scaling reveals how climate signals measured in the geological record alias transient variability, even during the most pronounced climatic perturbations of the Phanerozoic. Our findings indicate that the true attainable pace of climate change on timescales of greatest societal relevance is underestimated in geological archives.

Tip Speed Ratio Based Maximum Power Tracking Control of Variable Speed Wind Turbines; A Comprehensive Design

Directory of Open Access Journals (Sweden)

Murat Karabacak

2017-08-01

Full Text Available The most primitive control method of wind turbines used to generate electric energy from wind is the fixed speed control method. With this method, it is not possible that turbine input power is transferred to grid at maximum rate. For this reason, Maximum Power Tracking (MPT schemes are proposed. In order to implement MPT, the propeller has to rotate at a different speed for every different wind speed. This situation has led MPT based systems to be called Variable Speed Wind Turbine (VSWT systems. In VSWT systems, turbine input power can be transferred to grid at rates close to maximum power. When MPT based control of VSWT systems is the case, two important processes come into prominence. These are instantaneously determination and tracking of MPT point. In this study, using a Maximum Power Point Tracking (MPPT method based on tip speed ratio, power available in wind is transferred into grid over a back to back converter at maximum rate via a VSWT system with permanent magnet synchronous generator (PMSG. Besides a physical wind turbine simulator is modelled and simulated. Results show that a time varying MPPT point is tracked with a high performance.

Future changes over the Himalayas: Maximum and minimum temperature

Science.gov (United States)

Dimri, A. P.; Kumar, D.; Choudhary, A.; Maharana, P.

2018-03-01

An assessment of the projection of minimum and maximum air temperature over the Indian Himalayan region (IHR) from the COordinated Regional Climate Downscaling EXperiment- South Asia (hereafter, CORDEX-SA) regional climate model (RCM) experiments have been carried out under two different Representative Concentration Pathway (RCP) scenarios. The major aim of this study is to assess the probable future changes in the minimum and maximum climatology and its long-term trend under different RCPs along with the elevation dependent warming over the IHR. A number of statistical analysis such as changes in mean climatology, long-term spatial trend and probability distribution function are carried out to detect the signals of changes in climate. The study also tries to quantify the uncertainties associated with different model experiments and their ensemble in space, time and for different seasons. The model experiments and their ensemble show prominent cold bias over Himalayas for present climate. However, statistically significant higher warming rate (0.23-0.52 °C/decade) for both minimum and maximum air temperature (Tmin and Tmax) is observed for all the seasons under both RCPs. The rate of warming intensifies with the increase in the radiative forcing under a range of greenhouse gas scenarios starting from RCP4.5 to RCP8.5. In addition to this, a wide range of spatial variability and disagreements in the magnitude of trend between different models describes the uncertainty associated with the model projections and scenarios. The projected rate of increase of Tmin may destabilize the snow formation at the higher altitudes in the northern and western parts of Himalayan region, while rising trend of Tmax over southern flank may effectively melt more snow cover. Such combined effect of rising trend of Tmin and Tmax may pose a potential threat to the glacial deposits. The overall trend of Diurnal temperature range (DTR) portrays increasing trend across entire area with

Radon emanation of heterogeneous basin deposits in Kathmandu Valley, Nepal

Science.gov (United States)

Girault, Frédéric; Gajurel, Ananta Prasad; Perrier, Frédéric; Upreti, Bishal Nath; Richon, Patrick

2011-01-01

Effective radium-226 concentration ( EC Ra) has been measured in soil samples from seven horizontal and vertical profiles of terrace scarps in the northern part of Kathmandu Valley, Nepal. The samples belong to the Thimi, Gokarna, and Tokha Formations, dated from 50 to 14 ky BP, and represent a diverse fluvio-deltaic sedimentary facies mainly consisting of gravelly to coarse sands, black, orange and brown clays. EC Ra was measured in the laboratory by radon-222 emanation. The samples ( n = 177) are placed in air-tight glass containers, from which, after an accumulation time varying from 3 to 18 days, the concentration of radon-222, radioactive decay product of radium-226 and radioactive gas with a half-life of 3.8 days, is measured using scintillation flasks. The EC Ra values from the seven different profiles of the terrace deposits vary from 0.4 to 43 Bq kg -1, with profile averages ranging from 12 ± 1 to 27 ± 2 Bq kg -1. The values have a remarkable consistency along a particular horizon of sediment layers, clearly demonstrating that these values can be used for long distance correlations of the sediment horizons. Widely separated sediment profiles, representing similar stratigraphic positions, exhibit consistent EC Ra values in corresponding stratigraphic sediment layers. EC Ra measurements therefore appear particularly useful for lithologic and stratigraphic discriminations. For comparison, EC Ra values of soils from different localities having various sources of origin were also obtained: 9.2 ± 0.4 Bq kg -1 in soils of Syabru-Bensi (Central Nepal), 23 ± 1 Bq kg -1 in red residual soils of the Bhattar-Trisuli Bazar terrace (North of Kathmandu), 17.1 ± 0.3 Bq kg -1 in red residual soils of terrace of Kalikasthan (North of Trisuli Bazar) and 10 ± 1 Bq kg -1 in red residual soils of a site near Nagarkot (East of Kathmandu). The knowledge of EC Ra values for these various soils is important for modelling radon exhalation at the ground surface, in particular

Radon emanation of heterogeneous basin deposits in Kathmandu Valley, Nepal

International Nuclear Information System (INIS)

Girault, F.; Perrier, F.; Ananta Prasad Gajurel; Bishal Nath Upreti; Richon, P.

2011-01-01

Effective radium-226 concentration (EC Ra ) has been measured in soil samples from seven horizontal and vertical profiles of terrace scarps in the northern part of Kathmandu Valley, Nepal. The samples belong to the Thimi, Gokarna, and Tokha Formations, dated from 50 to 14 ky BP, and represent a diverse fluvio-deltaic sedimentary facies mainly consisting of gravelly to coarse sands, black, orange and brown clays. EC Ra was measured in the laboratory by radon-222 emanation. The samples (n = 177) are placed in airtight glass containers, from which, after an accumulation time varying from 3 to 18 days, the concentration of radon-222, radioactive decay product of radium-226 and radioactive gas with a half-life of 3.8 days, is measured using scintillation flasks. The EC Ra values from the seven different profiles of the terrace deposits vary from 0.4 to 43 Bq kg -1 , with profile averages ranging from 12 ± 1 to 27 ± 2 Bq kg -1 . The values have a remarkable consistency along a particular horizon of sediment layers, clearly demonstrating that these values can be used for long distance correlations of the sediment horizons. Widely separated sediment profiles, representing similar stratigraphic positions, exhibit consistent EC Ra values in corresponding stratigraphic sediment layers. EC Ra measurements therefore appear particularly useful for lithologic and stratigraphic discriminations. For comparison, EC Ra values of soils from different localities having various sources of origin were also obtained: 9.2 ± 0.4 Bq kg -1 in soils of Syabru-Bensi (Central Nepal), 23 ± 1 Bq kg -1 in red residual soils of the Bhattar-Trisuli Bazar terrace (North of Kathmandu), 17.1 ± 0.3 Bq kg -1 in red residual soils of terrace of Kalikasthan (North of Trisuli Bazar) and 10 ± 1 Bq kg -1 in red residual soils of a site near Nagarkot (East of Kathmandu). The knowledge of EC Ra values for these various soils is important for modelling radon exhalation at the ground surface, in particular

Maximum Entropy and Theory Construction: A Reply to Favretti

Directory of Open Access Journals (Sweden)

John Harte

2018-04-01

Full Text Available In the maximum entropy theory of ecology (METE, the form of a function describing the distribution of abundances over species and metabolic rates over individuals in an ecosystem is inferred using the maximum entropy inference procedure. Favretti shows that an alternative maximum entropy model exists that assumes the same prior knowledge and makes predictions that differ from METE’s. He shows that both cannot be correct and asserts that his is the correct one because it can be derived from a classic microstate-counting calculation. I clarify here exactly what the core entities and definitions are for METE, and discuss the relevance of two critical issues raised by Favretti: the existence of a counting procedure for microstates and the choices of definition of the core elements of a theory. I emphasize that a theorist controls how the core entities of his or her theory are defined, and that nature is the final arbiter of the validity of a theory.

Heat transfer and flow structure evaluation of a synthetic jet emanating from a planar heat sink

International Nuclear Information System (INIS)

Manning, Paul; Persoons, Tim; Murray, Darina

2014-01-01

Direct impinging synthetic jets are a proven method for heat transfer enhancement, and have been subject to extensive research. However, despite the vast amount of research into direct synthetic jet impingement, there has been little research investigating the effects of a synthetic jet emanating from a heated surface, this forms the basis of the current research investigation. Both single and multiple orifices are integrated into a planar heat sink forming a synthetic jet, thus allowing the heat transfer enhancement and flow structures to be assessed. The heat transfer analysis highlighted that the multiple orifice synthetic jet resulted in the greatest heat transfer enhancements. The flow structures responsible for these enhancements were identified using a combination of flow visualisation, thermal imaging and thermal boundary layer analysis. The flow structure analysis identified that the synthetic jets decreased the thermal boundary layer thickness resulting in a more effective convective heat transfer process. Flow visualisation revealed entrainment of local air adjacent to the heated surface; this occurred from vortex roll-up at the surface of the heat sink and from the highly sheared jet flow. Furthermore, a secondary entrainment was identified which created a surface impingement effect. It is proposed that all three flow features enhance the heat transfer characteristics of the system.

Maximum likelihood convolutional decoding (MCD) performance due to system losses

Science.gov (United States)

Webster, L.

1976-01-01

A model for predicting the computational performance of a maximum likelihood convolutional decoder (MCD) operating in a noisy carrier reference environment is described. This model is used to develop a subroutine that will be utilized by the Telemetry Analysis Program to compute the MCD bit error rate. When this computational model is averaged over noisy reference phase errors using a high-rate interpolation scheme, the results are found to agree quite favorably with experimental measurements.

75 FR 52947 - Maximum Per Diem Rates for the Continental United States (CONUS)

Science.gov (United States)

2010-08-30

... per diem rate setting process enhances the government's ability to obtain policy-compliant lodging where it is needed. In conjunction with the annual lodging study, GSA identified five new non-standard... diem localities and updates the standard CONUS rate. The CONUS per diem rates prescribed in Bulletin 11...

STUDY ON MAXIMUM SPECIFIC SLUDGE ACIVITY OF DIFFERENT ANAEROBIC GRANULAR SLUDGE BY BATCH TESTS

Institute of Scientific and Technical Information of China (English)

无

2001-01-01

The maximum specific sludge activity of granular sludge from large-scale UASB, IC and Biobed anaerobic reactors were investigated by batch tests. The limitation factors related to maximum specific sludge activity (diffusion, substrate sort, substrate concentration and granular size) were studied. The general principle and procedure for the precise measurement of maximum specific sludge activity were suggested. The potential capacity of loading rate of the IC and Biobed anaerobic reactors were analyzed and compared by use of the batch tests results.

What controls the maximum magnitude of injection-induced earthquakes?

Science.gov (United States)

Eaton, D. W. S.

2017-12-01

Three different approaches for estimation of maximum magnitude are considered here, along with their implications for managing risk. The first approach is based on a deterministic limit for seismic moment proposed by McGarr (1976), which was originally designed for application to mining-induced seismicity. This approach has since been reformulated for earthquakes induced by fluid injection (McGarr, 2014). In essence, this method assumes that the upper limit for seismic moment release is constrained by the pressure-induced stress change. A deterministic limit is given by the product of shear modulus and the net injected fluid volume. This method is based on the assumptions that the medium is fully saturated and in a state of incipient failure. An alternative geometrical approach was proposed by Shapiro et al. (2011), who postulated that the rupture area for an induced earthquake falls entirely within the stimulated volume. This assumption reduces the maximum-magnitude problem to one of estimating the largest potential slip surface area within a given stimulated volume. Finally, van der Elst et al. (2016) proposed that the maximum observed magnitude, statistically speaking, is the expected maximum value for a finite sample drawn from an unbounded Gutenberg-Richter distribution. These three models imply different approaches for risk management. The deterministic method proposed by McGarr (2014) implies that a ceiling on the maximum magnitude can be imposed by limiting the net injected volume, whereas the approach developed by Shapiro et al. (2011) implies that the time-dependent maximum magnitude is governed by the spatial size of the microseismic event cloud. Finally, the sample-size hypothesis of Van der Elst et al. (2016) implies that the best available estimate of the maximum magnitude is based upon observed seismicity rate. The latter two approaches suggest that real-time monitoring is essential for effective management of risk. A reliable estimate of maximum

Cosmic shear measurement with maximum likelihood and maximum a posteriori inference

Science.gov (United States)

Hall, Alex; Taylor, Andy

2017-06-01

We investigate the problem of noise bias in maximum likelihood and maximum a posteriori estimators for cosmic shear. We derive the leading and next-to-leading order biases and compute them in the context of galaxy ellipticity measurements, extending previous work on maximum likelihood inference for weak lensing. We show that a large part of the bias on these point estimators can be removed using information already contained in the likelihood when a galaxy model is specified, without the need for external calibration. We test these bias-corrected estimators on simulated galaxy images similar to those expected from planned space-based weak lensing surveys, with promising results. We find that the introduction of an intrinsic shape prior can help with mitigation of noise bias, such that the maximum a posteriori estimate can be made less biased than the maximum likelihood estimate. Second-order terms offer a check on the convergence of the estimators, but are largely subdominant. We show how biases propagate to shear estimates, demonstrating in our simple set-up that shear biases can be reduced by orders of magnitude and potentially to within the requirements of planned space-based surveys at mild signal-to-noise ratio. We find that second-order terms can exhibit significant cancellations at low signal-to-noise ratio when Gaussian noise is assumed, which has implications for inferring the performance of shear-measurement algorithms from simplified simulations. We discuss the viability of our point estimators as tools for lensing inference, arguing that they allow for the robust measurement of ellipticity and shear.

Maximum Power Point Tracking of Photovoltaic System for Traffic Light Application

Directory of Open Access Journals (Sweden)

Riza Muhida

2013-07-01

Full Text Available Photovoltaic traffic light system is a significant application of renewable energy source. The development of the system is an alternative effort of local authority to reduce expenditure for paying fees to power supplier which the power comes from conventional energy source. Since photovoltaic (PV modules still have relatively low conversion efficiency, an alternative control of maximum power point tracking (MPPT method is applied to the traffic light system. MPPT is intended to catch up the maximum power at daytime in order to charge the battery at the maximum rate in which the power from the battery is intended to be used at night time or cloudy day. MPPT is actually a DC-DC converter that can step up or down voltage in order to achieve the maximum power using Pulse Width Modulation (PWM control. From experiment, we obtained the voltage of operation using MPPT is at 16.454 V, this value has error of 2.6%, if we compared with maximum power point voltage of PV module that is 16.9 V. Based on this result it can be said that this MPPT control works successfully to deliver the power from PV module to battery maximally.

Probable Maximum Earthquake Magnitudes for the Cascadia Subduction

Science.gov (United States)

Rong, Y.; Jackson, D. D.; Magistrale, H.; Goldfinger, C.

2013-12-01

The concept of maximum earthquake magnitude (mx) is widely used in seismic hazard and risk analysis. However, absolute mx lacks a precise definition and cannot be determined from a finite earthquake history. The surprising magnitudes of the 2004 Sumatra and the 2011 Tohoku earthquakes showed that most methods for estimating mx underestimate the true maximum if it exists. Thus, we introduced the alternate concept of mp(T), probable maximum magnitude within a time interval T. The mp(T) can be solved using theoretical magnitude-frequency distributions such as Tapered Gutenberg-Richter (TGR) distribution. The two TGR parameters, β-value (which equals 2/3 b-value in the GR distribution) and corner magnitude (mc), can be obtained by applying maximum likelihood method to earthquake catalogs with additional constraint from tectonic moment rate. Here, we integrate the paleoseismic data in the Cascadia subduction zone to estimate mp. The Cascadia subduction zone has been seismically quiescent since at least 1900. Fortunately, turbidite studies have unearthed a 10,000 year record of great earthquakes along the subduction zone. We thoroughly investigate the earthquake magnitude-frequency distribution of the region by combining instrumental and paleoseismic data, and using the tectonic moment rate information. To use the paleoseismic data, we first estimate event magnitudes, which we achieve by using the time interval between events, rupture extent of the events, and turbidite thickness. We estimate three sets of TGR parameters: for the first two sets, we consider a geographically large Cascadia region that includes the subduction zone, and the Explorer, Juan de Fuca, and Gorda plates; for the third set, we consider a narrow geographic region straddling the subduction zone. In the first set, the β-value is derived using the GCMT catalog. In the second and third sets, the β-value is derived using both the GCMT and paleoseismic data. Next, we calculate the corresponding mc

Fragile-to-fragile liquid transition at Tg and stable-glass phase nucleation rate maximum at the Kauzmann temperature TK

International Nuclear Information System (INIS)

Tournier, Robert F.

2014-01-01

An undercooled liquid is unstable. The driving force of the glass transition at T g is a change of the undercooled-liquid Gibbs free energy. The classical Gibbs free energy change for a crystal formation is completed including an enthalpy saving. The crystal growth critical nucleus is used as a probe to observe the Laplace pressure change Δp accompanying the enthalpy change −V m ×Δp at T g where V m is the molar volume. A stable glass–liquid transition model predicts the specific heat jump of fragile liquids at T≤T g , the Kauzmann temperature T K where the liquid entropy excess with regard to crystal goes to zero, the equilibrium enthalpy between T K and T g , the maximum nucleation rate at T K of superclusters containing magic atom numbers, and the equilibrium latent heats at T g and T K . Strong-to-fragile and strong-to-strong liquid transitions at T g are also described and all their thermodynamic parameters are determined from their specific heat jumps. The existence of fragile liquids quenched in the amorphous state, which do not undergo liquid–liquid transition during heating preceding their crystallization, is predicted. Long ageing times leading to the formation at T K of a stable glass composed of superclusters containing up to 147 atom, touching and interpenetrating, are evaluated from nucleation rates. A fragile-to-fragile liquid transition occurs at T g without stable-glass formation while a strong glass is stable after transition

Measuring maximum and standard metabolic rates using intermittent-flow respirometry: a student laboratory investigation of aerobic metabolic scope and environmental hypoxia in aquatic breathers.

Science.gov (United States)

Rosewarne, P J; Wilson, J M; Svendsen, J C

2016-01-01

Metabolic rate is one of the most widely measured physiological traits in animals and may be influenced by both endogenous (e.g. body mass) and exogenous factors (e.g. oxygen availability and temperature). Standard metabolic rate (SMR) and maximum metabolic rate (MMR) are two fundamental physiological variables providing the floor and ceiling in aerobic energy metabolism. The total amount of energy available between these two variables constitutes the aerobic metabolic scope (AMS). A laboratory exercise aimed at an undergraduate level physiology class, which details the appropriate data acquisition methods and calculations to measure oxygen consumption rates in rainbow trout Oncorhynchus mykiss, is presented here. Specifically, the teaching exercise employs intermittent flow respirometry to measure SMR and MMR, derives AMS from the measurements and demonstrates how AMS is affected by environmental oxygen. Students' results typically reveal a decline in AMS in response to environmental hypoxia. The same techniques can be applied to investigate the influence of other key factors on metabolic rate (e.g. temperature and body mass). Discussion of the results develops students' understanding of the mechanisms underlying these fundamental physiological traits and the influence of exogenous factors. More generally, the teaching exercise outlines essential laboratory concepts in addition to metabolic rate calculations, data acquisition and unit conversions that enhance competency in quantitative analysis and reasoning. Finally, the described procedures are generally applicable to other fish species or aquatic breathers such as crustaceans (e.g. crayfish) and provide an alternative to using higher (or more derived) animals to investigate questions related to metabolic physiology. © 2016 The Fisheries Society of the British Isles.

A conrparison of optirnunl and maximum reproduction using the rat ...

African Journals Online (AJOL)

of pigs to increase reproduction rate of sows (te Brake,. 1978; Walker et at., 1979; Kemm et at., 1980). However, no experimental evidence exists that this strategy would in fact improve biological efficiency. In this pilot experiment, an attempt was made to compare systems of optimum or maximum reproduction using the rat.

Influence of phase separation on the anaerobic digestion of glucose: maximum COD turnover rate during continuous operation

Energy Technology Data Exchange (ETDEWEB)

Cohen, A; Van Andel, J G; Breure, A M; Van Deursen, A

1980-01-01

A mineral medium containing 1% of glucose as the main carbon source was subjected to one-phase and two-phase anaerobic digestion processes under comparable conditions. The one-phase system combined acidogenic and methanogenic populations allowing a complete conversion of the carbon source into gaseous end products and biomass. The two-phase system consists of an acid reactor and a methane reactor connected in series allowing sequential acidogenesis and methanogenesis. Performance of the one-phase system is compared with that of the two-phase system. Maximum turnover of COD was determined for each system. Maximum specific sludge loading of the two-phase system was more than three times higher than that of the one-phase system. Effects of overloading each system were determined. The eco-physiological significance of phase separation is discussed briefly. (2 diagrams, 5 graphs, 41 references, 5 tables)

Tracing Fast Electron Beams Emanating from the Magnetic Reconnection Site in a Solar Jet

Science.gov (United States)

Chen, B.; Yu, S.; Battaglia, M.; Krucker, S.

2017-12-01

Fast electron beams propagating in the solar corona can emit radio waves commonly known as type III radio bursts. At decimetric wavelengths, these bursts are emitted from the low corona where flare energy release is thought to take place. As such, decimetric type III radio bursts can serve as an excellent tool to directly trace fast electron beams in the vicinity of the flare energy release site. Here we report observations of decimetric type III bursts during a jet event using the Jansky Very Large Array (VLA) in 1-2 GHz. Taking advantage of VLA's highly sensitive spectral imaging capability with an ultra-high cadence of 50 ms, we derive detailed trajectories of fast electron beams (with a bulk speed of at least 0.3-0.5c, or several tens of keV) and place them in the context of extreme ultraviolet and X-ray images obtained by SDO/AIA and RHESSI. Our results show that the electron beams originated in a region just below the jet and above the lower-lying small-scale flare loops, presumably where the magnetic energy release took place. We show that the electron beams appear in groups, each with a duration of only a few seconds. Each group, consisting of beams propagating along magnetic field lines at different angles, is seen to emanate from a single site trailing the jet, interpreted as the magnetic reconnection null point. Our results suggest, at least for the present case, that the fast electron beams were energized directly at the magnetic reconnection site which was highly inhomogeneous and fragmentary possibly down to kilometer scales.

Maximum power point tracking: a cost saving necessity in solar energy systems

Energy Technology Data Exchange (ETDEWEB)

Enslin, J H.R. [Stellenbosch Univ. (South Africa). Dept. of Electrical and Electronic Engineering

1992-12-01

A well engineered renewable remote energy system, utilizing the principal of Maximum Power Point Tracking (MPPT) can improve cost effectiveness, has a higher reliability and can improve the quality of life in remote areas. A high-efficient power electronic converter, for converting the output voltage of a solar panel, or wind generator, to the required DC battery bus voltage has been realized. The converter is controlled to track the maximum power point of the input source under varying input and output parameters. Maximum power point tracking for relative small systems is achieved by maximization of the output current in a battery charging regulator, using an optimized hill-climbing, inexpensive microprocessor based algorithm. Through practical field measurements it is shown that a minimum input source saving of between 15 and 25% on 3-5 kWh/day systems can easily be achieved. A total cost saving of at least 10-15% on the capital cost of these systems are achievable for relative small rating Remote Area Power Supply (RAPS) systems. The advantages at large temperature variations and high power rated systems are much higher. Other advantages include optimal sizing and system monitor and control. (author).

Maximum Acceleration Recording Circuit

Science.gov (United States)

Bozeman, Richard J., Jr.

1995-01-01

Coarsely digitized maximum levels recorded in blown fuses. Circuit feeds power to accelerometer and makes nonvolatile record of maximum level to which output of accelerometer rises during measurement interval. In comparison with inertia-type single-preset-trip-point mechanical maximum-acceleration-recording devices, circuit weighs less, occupies less space, and records accelerations within narrower bands of uncertainty. In comparison with prior electronic data-acquisition systems designed for same purpose, circuit simpler, less bulky, consumes less power, costs and analysis of data recorded in magnetic or electronic memory devices. Circuit used, for example, to record accelerations to which commodities subjected during transportation on trucks.

The response of the southern Greenland ice sheet to the Holocene thermal maximum

DEFF Research Database (Denmark)

Larsen, Nicolaj Krog; Kjaer, Kurt H.; Lecavalier, Benoit

2015-01-01

contribution of 0.16 m sea-level equivalent from the entire Greenland ice sheet, with a centennial ice loss rate of as much as 100 Gt/yr for several millennia during the Holocene thermal maximum. Our results provide an estimate of the long-term rates of volume loss that can be expected in the future...

Neutron spectra unfolding with maximum entropy and maximum likelihood

International Nuclear Information System (INIS)

Itoh, Shikoh; Tsunoda, Toshiharu

1989-01-01

A new unfolding theory has been established on the basis of the maximum entropy principle and the maximum likelihood method. This theory correctly embodies the Poisson statistics of neutron detection, and always brings a positive solution over the whole energy range. Moreover, the theory unifies both problems of overdetermined and of underdetermined. For the latter, the ambiguity in assigning a prior probability, i.e. the initial guess in the Bayesian sense, has become extinct by virtue of the principle. An approximate expression of the covariance matrix for the resultant spectra is also presented. An efficient algorithm to solve the nonlinear system, which appears in the present study, has been established. Results of computer simulation showed the effectiveness of the present theory. (author)

Maximum Power from a Solar Panel

Directory of Open Access Journals (Sweden)

Michael Miller

2010-01-01

Full Text Available Solar energy has become a promising alternative to conventional fossil fuel sources. Solar panels are used to collect solar radiation and convert it into electricity. One of the techniques used to maximize the effectiveness of this energy alternative is to maximize the power output of the solar collector. In this project the maximum power is calculated by determining the voltage and the current of maximum power. These quantities are determined by finding the maximum value for the equation for power using differentiation. After the maximum values are found for each time of day, each individual quantity, voltage of maximum power, current of maximum power, and maximum power is plotted as a function of the time of day.

Petroleum production at Maximum Efficient Rate Naval Petroleum Reserve No. 1 (Elk Hills), Kern County, California. Final Supplemental Environmental Impact Statement

Energy Technology Data Exchange (ETDEWEB)

1993-07-01

This document provides an analysis of the potential impacts associated with the proposed action, which is continued operation of Naval Petroleum Reserve No. I (NPR-1) at the Maximum Efficient Rate (MER) as authorized by Public law 94-258, the Naval Petroleum Reserves Production Act of 1976 (Act). The document also provides a similar analysis of alternatives to the proposed action, which also involve continued operations, but under lower development scenarios and lower rates of production. NPR-1 is a large oil and gas field jointly owned and operated by the federal government and Chevron U.SA Inc. (CUSA) pursuant to a Unit Plan Contract that became effective in 1944; the government`s interest is approximately 78% and CUSA`s interest is approximately 22%. The government`s interest is under the jurisdiction of the United States Department of Energy (DOE). The facility is approximately 17,409 acres (74 square miles), and it is located in Kern County, California, about 25 miles southwest of Bakersfield and 100 miles north of Los Angeles in the south central portion of the state. The environmental analysis presented herein is a supplement to the NPR-1 Final Environmental Impact Statement of that was issued by DOE in 1979 (1979 EIS). As such, this document is a Supplemental Environmental Impact Statement (SEIS).

Radon emanations: a tectonic indicator in the Dharamsala area of Himalayan Frontal Zone, Himachal Pradesh

International Nuclear Information System (INIS)

Dhar, Sunil

2013-01-01

While throughout the length of Himalayas good exposures of the tertiary and the pre-Tertiary occurs occur, but in the Dharamsala and its adjoining areas of Himalayan Frontal Zone, tertiary and the pre-Tertiary rocks are present within a short aerial distance. This diverse lithology within a short span of distance along with the structural heterogeneity has made this region of Himalayas tectonically significant. This unique tectano-stratigraphic configuration of this area is primarily attributed to the major faults and folds which are either along the Himalayan trend or transverse to it. Interestingly the area is seismically active and falls in the High Seismic Zone-V of seismic atlas of India. It has been observed that regional thrusts systems and lineaments, control seismo-tectonic activity in the region. Contemporary geomorphological re-adjustments in the form of erosion intensity (meandering/drainage pattern or river incision) as a result of active nature of lineaments have been observed. In addition, due to the rampant seismic activity in the region especially in year 2013, the area has witnessed a sequence of landslides. The study further reveals these the signatures of morphological adjustment coincide with zones which have deciphered higher proportions of radon activity. Because radon transport through rocks is largely dependent on the geology of the area, which includes lithology, compaction, porosity structural/tectonic features like thrusts, faults, joints and fractures. Occurrences of landslide the thrust zones, coupled with high emanations of radon (both in soil and water) alludes attention towards dominant role of neo-tectonic activity in the area. (author)

Maximum heat flux in boiling in a large volume

International Nuclear Information System (INIS)

Bergmans, Dzh.

1976-01-01

Relationships are derived for the maximum heat flux qsub(max) without basing on the assumptions of both the critical vapor velocity corresponding to the zero growth rate, and planar interface. The Helmholz nonstability analysis of vapor column has been made to this end. The results of this examination have been used to find maximum heat flux for spherical, cylindric and flat plate heaters. The conventional hydrodynamic theory was found to be incapable of producing a satisfactory explanation of qsub(max) for small heaters. The occurrence of qsub(max) in the present case can be explained by inadequate removal of vapor output from the heater (the force of gravity for cylindrical heaters and surface tension for the spherical ones). In case of flat plate heater the qsub(max) value can be explained with the help of the hydrodynamic theory

Development of a Soundproof Device for 950 Watt rated Portable ...

African Journals Online (AJOL)

Dr. N.A Musa

ABSTRACT: The noise emanating from generators has adverse effects on ... soundproof device was carried out, and the sound pressure level of the ... Heat resistance rubber pipe and. 8. ... attached to the exhaust of the generator, respectively.

Noncircular Chainrings Do Not Influence Maximum Cycling Power.

Science.gov (United States)

Leong, Chee-Hoi; Elmer, Steven J; Martin, James C

2017-12-01

Noncircular chainrings could increase cycling power by prolonging the powerful leg extension/flexion phases, and curtailing the low-power transition phases. We compared maximal cycling power-pedaling rate relationships, and joint-specific kinematics and powers across 3 chainring eccentricities (CON = 1.0; LOW ecc  = 1.13; HIGH ecc  = 1.24). Part I: Thirteen cyclists performed maximal inertial-load cycling under 3 chainring conditions. Maximum cycling power and optimal pedaling rate were determined. Part II: Ten cyclists performed maximal isokinetic cycling (120 rpm) under the same 3 chainring conditions. Pedal and joint-specific powers were determined using pedal forces and limb kinematics. Neither maximal cycling power nor optimal pedaling rate differed across chainring conditions (all p > .05). Peak ankle angular velocity for HIGH ecc was less than CON (p pedal system allowed cyclists to manipulate ankle angular velocity to maintain their preferred knee and hip actions, suggesting maximizing extension/flexion and minimizing transition phases may be counterproductive for maximal power.

Optimized measurement of radium-226 concentration in liquid samples with radon-222 emanation

International Nuclear Information System (INIS)

Perrier, Frédéric; Aupiais, Jean; Girault, Frédéric; Przylibski, Tadeusz A.; Bouquerel, Hélène

2016-01-01

Measuring radium-226 concentration in liquid samples using radon-222 emanation remains competitive with techniques such as liquid scintillation, alpha or mass spectrometry. Indeed, we show that high-precision can be obtained without air circulation, using an optimal air to liquid volume ratio and moderate heating. Cost-effective and efficient measurement of radon concentration is achieved by scintillation flasks and sufficiently long counting times for signal and background. More than 400 such measurements were performed, including 39 dilution experiments, a successful blind measurement of six reference test solutions, and more than 110 repeated measurements. Under optimal conditions, uncertainties reach 5% for an activity concentration of 100 mBq L"−"1 and 10% for 10 mBq L"−"1. While the theoretical detection limit predicted by Monte Carlo simulation is around 3 mBq L"−"1, a conservative experimental estimate is rather 5 mBq L"−"1, corresponding to 0.14 fg g"−"1. The method was applied to 47 natural waters, 51 commercial waters, and 17 wine samples, illustrating that it could be an option for liquids that cannot be easily measured by other methods. Counting of scintillation flasks can be done in remote locations in absence of electricity supply, using a solar panel. Thus, this portable method, which has demonstrated sufficient accuracy for numerous natural liquids, could be useful in geological and environmental problems, with the additional benefit that it can be applied in isolated locations and in circumstances when samples cannot be transported. - Highlights: • Radium-226 concentration measured with optimized accumulation in a container. • Radon-222 in air measured precisely with scintillation flasks and long countings. • Method tested by repetition tests, dilution experiments, and successful blind tests. • Estimated conservative detection limit without pre-concentration is 5 mBq L"−"1. • Method is portable, cost

Maximum concentrations at work and maximum biologically tolerable concentration for working materials 1991

International Nuclear Information System (INIS)

1991-01-01

The meaning of the term 'maximum concentration at work' in regard of various pollutants is discussed. Specifically, a number of dusts and smokes are dealt with. The valuation criteria for maximum biologically tolerable concentrations for working materials are indicated. The working materials in question are corcinogeneous substances or substances liable to cause allergies or mutate the genome. (VT) [de

A thermoelectric generator using loop heat pipe and design match for maximum-power generation

KAUST Repository

Huang, Bin-Juine

2015-09-05

The present study focuses on the thermoelectric generator (TEG) using loop heat pipe (LHP) and design match for maximum-power generation. The TEG uses loop heat pipe, a passive cooling device, to dissipate heat without consuming power and free of noise. The experiments for a TEG with 4W rated power show that the LHP performs very well with overall thermal resistance 0.35 K W-1, from the cold side of TEG module to the ambient. The LHP is able to dissipate heat up to 110W and is maintenance free. The TEG design match for maximum-power generation, called “near maximum-power point operation (nMPPO)”, is studied to eliminate the MPPT (maximum-power point tracking controller). nMPPO is simply a system design which properly matches the output voltage of TEG with the battery. It is experimentally shown that TEG using design match for maximum-power generation (nMPPO) performs better than TEG with MPPT.

40 CFR 1042.140 - Maximum engine power, displacement, power density, and maximum in-use engine speed.

Science.gov (United States)

2010-07-01

... cylinders having an internal diameter of 13.0 cm and a 15.5 cm stroke length, the rounded displacement would... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Maximum engine power, displacement... Maximum engine power, displacement, power density, and maximum in-use engine speed. This section describes...

Credal Networks under Maximum Entropy

OpenAIRE

Lukasiewicz, Thomas

2013-01-01

We apply the principle of maximum entropy to select a unique joint probability distribution from the set of all joint probability distributions specified by a credal network. In detail, we start by showing that the unique joint distribution of a Bayesian tree coincides with the maximum entropy model of its conditional distributions. This result, however, does not hold anymore for general Bayesian networks. We thus present a new kind of maximum entropy models, which are computed sequentially. ...

The maximum contraceptive prevalence 'demand curve': guiding discussions on programmatic investments.

Science.gov (United States)

Weinberger, Michelle; Sonneveldt, Emily; Stover, John

2017-12-22

Most frameworks for family planning include both access and demand interventions. Understanding how these two are linked and when each should be prioritized is difficult. The maximum contraceptive prevalence 'demand curve' was created based on a relationship between the modern contraceptive prevalence rate (mCPR) and mean ideal number of children to allow for a quantitative assessment of the balance between access and demand interventions. The curve represents the maximum mCPR that is likely to be seen given fertility intentions and related norms and constructs that influence contraceptive use. The gap between a country's mCPR and this maximum is referred to as the 'potential use gap.' This concept can be used by countries to prioritize access investments where the gap is large, and discuss implications for future contraceptive use where the gap is small. It is also used within the FP Goals model to ensure mCPR growth from access interventions does not exceed available demand.

Maximum Quantum Entropy Method

OpenAIRE

Sim, Jae-Hoon; Han, Myung Joon

2018-01-01

Maximum entropy method for analytic continuation is extended by introducing quantum relative entropy. This new method is formulated in terms of matrix-valued functions and therefore invariant under arbitrary unitary transformation of input matrix. As a result, the continuation of off-diagonal elements becomes straightforward. Without introducing any further ambiguity, the Bayesian probabilistic interpretation is maintained just as in the conventional maximum entropy method. The applications o...

The Maximum Flux of Star-Forming Galaxies

Science.gov (United States)

Crocker, Roland M.; Krumholz, Mark R.; Thompson, Todd A.; Clutterbuck, Julie

2018-04-01

The importance of radiation pressure feedback in galaxy formation has been extensively debated over the last decade. The regime of greatest uncertainty is in the most actively star-forming galaxies, where large dust columns can potentially produce a dust-reprocessed infrared radiation field with enough pressure to drive turbulence or eject material. Here we derive the conditions under which a self-gravitating, mixed gas-star disc can remain hydrostatic despite trapped radiation pressure. Consistently taking into account the self-gravity of the medium, the star- and dust-to-gas ratios, and the effects of turbulent motions not driven by radiation, we show that galaxies can achieve a maximum Eddington-limited star formation rate per unit area \\dot{Σ }_*,crit ˜ 10^3 M_{⊙} pc-2 Myr-1, corresponding to a critical flux of F*, crit ˜ 1013L⊙ kpc-2 similar to previous estimates; higher fluxes eject mass in bulk, halting further star formation. Conversely, we show that in galaxies below this limit, our one-dimensional models imply simple vertical hydrostatic equilibrium and that radiation pressure is ineffective at driving turbulence or ejecting matter. Because the vast majority of star-forming galaxies lie below the maximum limit for typical dust-to-gas ratios, we conclude that infrared radiation pressure is likely unimportant for all but the most extreme systems on galaxy-wide scales. Thus, while radiation pressure does not explain the Kennicutt-Schmidt relation, it does impose an upper truncation on it. Our predicted truncation is in good agreement with the highest observed gas and star formation rate surface densities found both locally and at high redshift.

Weighted Maximum-Clique Transversal Sets of Graphs

OpenAIRE

Chuan-Min Lee

2011-01-01

A maximum-clique transversal set of a graph G is a subset of vertices intersecting all maximum cliques of G. The maximum-clique transversal set problem is to find a maximum-clique transversal set of G of minimum cardinality. Motivated by the placement of transmitters for cellular telephones, Chang, Kloks, and Lee introduced the concept of maximum-clique transversal sets on graphs in 2001. In this paper, we study the weighted version of the maximum-clique transversal set problem for split grap...

Calibration of a degassing-emanation line for 222Rn determination in seawater samples; Calibracao de uma linha de emanacao para determinacao de {sup 222}Rn em amostras de agua do mar

Energy Technology Data Exchange (ETDEWEB)

Farias, Luciana Aparecida

2002-07-01

The purpose of this study is to calibrate a degassing-emanation line and to determine {sup 222}Rn and {sup 226}Ra activity concentrations in seawater samples. This methodology, also called Lucas method, consists in the extraction of radon (originally dissolved in seawater), collection of the gas in a liquid nitrogen cold trap and transfer from the trap to an alpha scintillation cell. Total extraction efficiencies of the 4 degassing-emanation systems were determined by measuring {sup 226}Ra reference solutions. The efficiencies obtained for these 4 systems varied from 21 % to 62%. This work also presents preliminary results of a study carried out in a series of small embayements of Ubatuba, Sao Paulo State-Brazil: Flamengo Bay, Fortaleza Bay, Mar Virado Bay and Ubatuba Bay. Concentration of Rn in excess varied from 0,011 to 0,317 Bq/L for Flamengo Bay, from 0,009 to 0,130 Bq/L for Fortaleza Bay, from 0,018 to 0,050 Bq/L for Mar Virado Bay and from 0,004 to 0,120 Bq/L for Ubatuba Bay. The results obtained for the concentration of {sup 222}Rn in excess in a transect at Flamengo Bay varied from 0,002 to 0,036 Bq/L. Higher concentrations of {sup 222}Rn in excess were obtained in Flamengo Bay, Fortaleza Bay and Ubatuba bay. It was also observed that the concentration of {sup 222}Rn in excess increases with depth, as expected. (author)

Erich Regener and the ionisation maximum of the atmosphere

Science.gov (United States)

Carlson, P.; Watson, A. A.

2014-12-01

In the 1930s the German physicist Erich Regener (1881-1955) did important work on the measurement of the rate of production of ionisation deep under water and in the atmosphere. Along with one of his students, Georg Pfotzer, he discovered the altitude at which the production of ionisation in the atmosphere reaches a maximum, often, but misleadingly, called the Pfotzer maximum. Regener was one of the first to estimate the energy density of cosmic rays, an estimate that was used by Baade and Zwicky to bolster their postulate that supernovae might be their source. Yet Regener's name is less recognised by present-day cosmic ray physicists than it should be, largely because in 1937 he was forced to take early retirement by the National Socialists as his wife had Jewish ancestors. In this paper we briefly review his work on cosmic rays and recommend an alternative naming of the ionisation maximum. The influence that Regener had on the field through his son, his son-in-law, his grandsons and his students, and through his links with Rutherford's group in Cambridge, is discussed in an appendix. Regener was nominated for the Nobel Prize in Physics by Schrödinger in 1938. He died in 1955 at the age of 73.

Maximum power demand cost

International Nuclear Information System (INIS)

Biondi, L.

1998-01-01

The charging for a service is a supplier's remuneration for the expenses incurred in providing it. There are currently two charges for electricity: consumption and maximum demand. While no problem arises about the former, the issue is more complicated for the latter and the analysis in this article tends to show that the annual charge for maximum demand arbitrarily discriminates among consumer groups, to the disadvantage of some [it

Novel methods for estimating lithium-ion battery state of energy and maximum available energy

International Nuclear Information System (INIS)

Zheng, Linfeng; Zhu, Jianguo; Wang, Guoxiu; He, Tingting; Wei, Yiying

2016-01-01

Highlights: • Study on temperature, current, aging dependencies of maximum available energy. • Study on the various factors dependencies of relationships between SOE and SOC. • A quantitative relationship between SOE and SOC is proposed for SOE estimation. • Estimate maximum available energy by means of moving-window energy-integral. • The robustness and feasibility of the proposed approaches are systematic evaluated. - Abstract: The battery state of energy (SOE) allows a direct determination of the ratio between the remaining and maximum available energy of a battery, which is critical for energy optimization and management in energy storage systems. In this paper, the ambient temperature, battery discharge/charge current rate and cell aging level dependencies of battery maximum available energy and SOE are comprehensively analyzed. An explicit quantitative relationship between SOE and state of charge (SOC) for LiMn_2O_4 battery cells is proposed for SOE estimation, and a moving-window energy-integral technique is incorporated to estimate battery maximum available energy. Experimental results show that the proposed approaches can estimate battery maximum available energy and SOE with high precision. The robustness of the proposed approaches against various operation conditions and cell aging levels is systematically evaluated.

The Effects Of Asymmetric Transmission Of Exchange Rate On Inflation In Iran: Application Of Threshold Models

Directory of Open Access Journals (Sweden)

Naghdi Yazdan

2015-08-01

Full Text Available Given the recent fluctuation in the exchange rate and the presence of several factors such as the various economy-political sanctions (mainly embargos on oil and banking, extreme volatility in different economic fields, and consequently the devaluation of national and public procurement -A landmark that is emanating from exchange rate fluctuation - two points should be noted: First, it is essential to review the effect of exchange rate fluctuation on macro economic variables such as inflation and to provide appropriate policies. Second, the existence of this condition provides the chance to study the relation between exchange rate and inflation in a non-linear and asymmetric method. Hence, the present study seeks to use TAR model and, on the basis of monthly time series data over the period March 2002 to March 2014, to analyze the cross-asymmetric and non-linear exchange rate on consumer price index (CPI in Iran. The results also show the presence of an asymmetric long-term relationship between these variables (exchange rate and CPI. Also, in the Iranian economy, the effect of negative shocks of exchange rate on inflation is more sustainable than the one from positive shocks.

Relationship between visual prostate score (VPSS and maximum flow rate (Qmax in men with urinary tract symptoms

Directory of Open Access Journals (Sweden)

Mazhar A. Memon

2016-04-01

Full Text Available ABSTRACT Objective: To evaluate correlation between visual prostate score (VPSS and maximum flow rate (Qmax in men with lower urinary tract symptoms. Material and Methods: This is a cross sectional study conducted at a university Hospital. Sixty-seven adult male patients>50 years of age were enrolled in the study after signing an informed consent. Qmax and voided volume recorded at uroflowmetry graph and at the same time VPSS were assessed. The education level was assessed in various defined groups. Pearson correlation coefficient was computed for VPSS and Qmax. Results: Mean age was 66.1±10.1 years (median 68. The mean voided volume on uroflowmetry was 268±160mL (median 208 and the mean Qmax was 9.6±4.96mLs/sec (median 9.0. The mean VPSS score was 11.4±2.72 (11.0. In the univariate linear regression analysis there was strong negative (Pearson's correlation between VPSS and Qmax (r=848, p<0.001. In the multiple linear regression analyses there was a significant correlation between VPSS and Qmax (β-http://www.blogapaixonadosporviagens.com.br/p/caribe.html after adjusting the effect of age, voided volume (V.V and level of education. Multiple linear regression analysis done for independent variables and results showed that there was no significant correlation between the VPSS and independent factors including age (p=0.27, LOE (p=0.941 and V.V (p=0.082. Conclusion: There is a significant negative correlation between VPSS and Qmax. The VPSS can be used in lieu of IPSS score. Men even with limited educational background can complete VPSS without assistance.

Maximum Plant Uptakes for Water, Nutrients, and Oxygen Are Not Always Met by Irrigation Rate and Distribution in Water-based Cultivation Systems.

Science.gov (United States)

Blok, Chris; Jackson, Brian E; Guo, Xianfeng; de Visser, Pieter H B; Marcelis, Leo F M

2017-01-01

Growing on rooting media other than soils in situ -i.e., substrate-based growing- allows for higher yields than soil-based growing as transport rates of water, nutrients, and oxygen in substrate surpass those in soil. Possibly water-based growing allows for even higher yields as transport rates of water and nutrients in water surpass those in substrate, even though the transport of oxygen may be more complex. Transport rates can only limit growth when they are below a rate corresponding to maximum plant uptake. Our first objective was to compare Chrysanthemum growth performance for three water-based growing systems with different irrigation. We compared; multi-point irrigation into a pond (DeepFlow); one-point irrigation resulting in a thin film of running water (NutrientFlow) and multi-point irrigation as droplets through air (Aeroponic). Second objective was to compare press pots as propagation medium with nutrient solution as propagation medium. The comparison included DeepFlow water-rooted cuttings with either the stem 1 cm into the nutrient solution or with the stem 1 cm above the nutrient solution. Measurements included fresh weight, dry weight, length, water supply, nutrient supply, and oxygen levels. To account for differences in radiation sum received, crop performance was evaluated with Radiation Use Efficiency (RUE) expressed as dry weight over sum of Photosynthetically Active Radiation. The reference, DeepFlow with substrate-based propagation, showed the highest RUE, even while the oxygen supply provided by irrigation was potentially growth limiting. DeepFlow with water-based propagation showed 15-17% lower RUEs than the reference. NutrientFlow showed 8% lower RUE than the reference, in combination with potentially limiting irrigation supply of nutrients and oxygen. Aeroponic showed RUE levels similar to the reference and Aeroponic had non-limiting irrigation supply of water, nutrients, and oxygen. Water-based propagation affected the subsequent

Heart rate profile during exercise in patients with early repolarization.

Science.gov (United States)

Cay, Serkan; Cagirci, Goksel; Atak, Ramazan; Balbay, Yucel; Demir, Ahmet Duran; Aydogdu, Sinan

2010-09-01

Both early repolarization and altered heart rate profile are associated with sudden death. In this study, we aimed to demonstrate an association between early repolarization and heart rate profile during exercise. A total of 84 subjects were included in the study. Comparable 44 subjects with early repolarization and 40 subjects with normal electrocardiogram underwent exercise stress testing. Resting heart rate, maximum heart rate, heart rate increment and decrement were analyzed. Both groups were comparable for baseline characteristics including resting heart rate. Maximum heart rate, heart rate increment and heart rate decrement of the subjects in early repolarization group had significantly decreased maximum heart rate, heart rate increment and heart rate decrement compared to control group (all P decrement (multiple-adjusted OR of the risk of presence of early repolarization was 2.98 (95%CI 1.21-7.34) (P = 0.018) and 7.73 (95%CI 2.84-21.03) (P decrement compared to higher levels, respectively. Subjects with early repolarization have altered heart rate profile during exercise compared to control subjects. This can be related to sudden death.

49 CFR 230.24 - Maximum allowable stress.

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Maximum allowable stress. 230.24 Section 230.24... Allowable Stress § 230.24 Maximum allowable stress. (a) Maximum allowable stress value. The maximum allowable stress value on any component of a steam locomotive boiler shall not exceed 1/4 of the ultimate...

Hydraulic limits on maximum plant transpiration and the emergence of the safety-efficiency trade-off.

Science.gov (United States)

Manzoni, Stefano; Vico, Giulia; Katul, Gabriel; Palmroth, Sari; Jackson, Robert B; Porporato, Amilcare

2013-04-01

Soil and plant hydraulics constrain ecosystem productivity by setting physical limits to water transport and hence carbon uptake by leaves. While more negative xylem water potentials provide a larger driving force for water transport, they also cause cavitation that limits hydraulic conductivity. An optimum balance between driving force and cavitation occurs at intermediate water potentials, thus defining the maximum transpiration rate the xylem can sustain (denoted as E(max)). The presence of this maximum raises the question as to whether plants regulate transpiration through stomata to function near E(max). To address this question, we calculated E(max) across plant functional types and climates using a hydraulic model and a global database of plant hydraulic traits. The predicted E(max) compared well with measured peak transpiration across plant sizes and growth conditions (R = 0.86, P efficiency trade-off in plant xylem. Stomatal conductance allows maximum transpiration rates despite partial cavitation in the xylem thereby suggesting coordination between stomatal regulation and xylem hydraulic characteristics. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

A maximum power point tracking for photovoltaic-SPE system using a maximum current controller

Energy Technology Data Exchange (ETDEWEB)

Muhida, Riza [Osaka Univ., Dept. of Physical Science, Toyonaka, Osaka (Japan); Osaka Univ., Dept. of Electrical Engineering, Suita, Osaka (Japan); Park, Minwon; Dakkak, Mohammed; Matsuura, Kenji [Osaka Univ., Dept. of Electrical Engineering, Suita, Osaka (Japan); Tsuyoshi, Akira; Michira, Masakazu [Kobe City College of Technology, Nishi-ku, Kobe (Japan)

2003-02-01

Processes to produce hydrogen from solar photovoltaic (PV)-powered water electrolysis using solid polymer electrolysis (SPE) are reported. An alternative control of maximum power point tracking (MPPT) in the PV-SPE system based on the maximum current searching methods has been designed and implemented. Based on the characteristics of voltage-current and theoretical analysis of SPE, it can be shown that the tracking of the maximum current output of DC-DC converter in SPE side will track the MPPT of photovoltaic panel simultaneously. This method uses a proportional integrator controller to control the duty factor of DC-DC converter with pulse-width modulator (PWM). The MPPT performance and hydrogen production performance of this method have been evaluated and discussed based on the results of the experiment. (Author)

MEGA5: Molecular Evolutionary Genetics Analysis Using Maximum Likelihood, Evolutionary Distance, and Maximum Parsimony Methods

Science.gov (United States)

Tamura, Koichiro; Peterson, Daniel; Peterson, Nicholas; Stecher, Glen; Nei, Masatoshi; Kumar, Sudhir

2011-01-01

Comparative analysis of molecular sequence data is essential for reconstructing the evolutionary histories of species and inferring the nature and extent of selective forces shaping the evolution of genes and species. Here, we announce the release of Molecular Evolutionary Genetics Analysis version 5 (MEGA5), which is a user-friendly software for mining online databases, building sequence alignments and phylogenetic trees, and using methods of evolutionary bioinformatics in basic biology, biomedicine, and evolution. The newest addition in MEGA5 is a collection of maximum likelihood (ML) analyses for inferring evolutionary trees, selecting best-fit substitution models (nucleotide or amino acid), inferring ancestral states and sequences (along with probabilities), and estimating evolutionary rates site-by-site. In computer simulation analyses, ML tree inference algorithms in MEGA5 compared favorably with other software packages in terms of computational efficiency and the accuracy of the estimates of phylogenetic trees, substitution parameters, and rate variation among sites. The MEGA user interface has now been enhanced to be activity driven to make it easier for the use of both beginners and experienced scientists. This version of MEGA is intended for the Windows platform, and it has been configured for effective use on Mac OS X and Linux desktops. It is available free of charge from http://www.megasoftware.net. PMID:21546353

Lake Basin Fetch and Maximum Length/Width

Data.gov (United States)

Minnesota Department of Natural Resources — Linear features representing the Fetch, Maximum Length and Maximum Width of a lake basin. Fetch, maximum length and average width are calcuated from the lake polygon...

Maximum permissible voltage of YBCO coated conductors

Energy Technology Data Exchange (ETDEWEB)

Wen, J.; Lin, B.; Sheng, J.; Xu, J.; Jin, Z. [Department of Electrical Engineering, Shanghai Jiao Tong University, Shanghai (China); Hong, Z., E-mail: zhiyong.hong@sjtu.edu.cn [Department of Electrical Engineering, Shanghai Jiao Tong University, Shanghai (China); Wang, D.; Zhou, H.; Shen, X.; Shen, C. [Qingpu Power Supply Company, State Grid Shanghai Municipal Electric Power Company, Shanghai (China)

2014-06-15

Highlights: • We examine three kinds of tapes’ maximum permissible voltage. • We examine the relationship between quenching duration and maximum permissible voltage. • Continuous I{sub c} degradations under repetitive quenching where tapes reaching maximum permissible voltage. • The relationship between maximum permissible voltage and resistance, temperature. - Abstract: Superconducting fault current limiter (SFCL) could reduce short circuit currents in electrical power system. One of the most important thing in developing SFCL is to find out the maximum permissible voltage of each limiting element. The maximum permissible voltage is defined as the maximum voltage per unit length at which the YBCO coated conductors (CC) do not suffer from critical current (I{sub c}) degradation or burnout. In this research, the time of quenching process is changed and voltage is raised until the I{sub c} degradation or burnout happens. YBCO coated conductors test in the experiment are from American superconductor (AMSC) and Shanghai Jiao Tong University (SJTU). Along with the quenching duration increasing, the maximum permissible voltage of CC decreases. When quenching duration is 100 ms, the maximum permissible of SJTU CC, 12 mm AMSC CC and 4 mm AMSC CC are 0.72 V/cm, 0.52 V/cm and 1.2 V/cm respectively. Based on the results of samples, the whole length of CCs used in the design of a SFCL can be determined.

Maximum-power-point tracking control of solar heating system

KAUST Repository

Huang, Bin-Juine

2012-11-01

The present study developed a maximum-power point tracking control (MPPT) technology for solar heating system to minimize the pumping power consumption at an optimal heat collection. The net solar energy gain Q net (=Q s-W p/η e) was experimentally found to be the cost function for MPPT with maximum point. The feedback tracking control system was developed to track the optimal Q net (denoted Q max). A tracking filter which was derived from the thermal analytical model of the solar heating system was used to determine the instantaneous tracking target Q max(t). The system transfer-function model of solar heating system was also derived experimentally using a step response test and used in the design of tracking feedback control system. The PI controller was designed for a tracking target Q max(t) with a quadratic time function. The MPPT control system was implemented using a microprocessor-based controller and the test results show good tracking performance with small tracking errors. It is seen that the average mass flow rate for the specific test periods in five different days is between 18.1 and 22.9kg/min with average pumping power between 77 and 140W, which is greatly reduced as compared to the standard flow rate at 31kg/min and pumping power 450W which is based on the flow rate 0.02kg/sm 2 defined in the ANSI/ASHRAE 93-1986 Standard and the total collector area 25.9m 2. The average net solar heat collected Q net is between 8.62 and 14.1kW depending on weather condition. The MPPT control of solar heating system has been verified to be able to minimize the pumping energy consumption with optimal solar heat collection. © 2012 Elsevier Ltd.

Receiver function estimated by maximum entropy deconvolution

Institute of Scientific and Technical Information of China (English)

吴庆举; 田小波; 张乃铃; 李卫平; 曾融生

2003-01-01

Maximum entropy deconvolution is presented to estimate receiver function, with the maximum entropy as the rule to determine auto-correlation and cross-correlation functions. The Toeplitz equation and Levinson algorithm are used to calculate the iterative formula of error-predicting filter, and receiver function is then estimated. During extrapolation, reflective coefficient is always less than 1, which keeps maximum entropy deconvolution stable. The maximum entropy of the data outside window increases the resolution of receiver function. Both synthetic and real seismograms show that maximum entropy deconvolution is an effective method to measure receiver function in time-domain.

Radiological analyses of France Telecom surge arresters. Study performed for the CGT FAPT Cantal

International Nuclear Information System (INIS)

2010-02-01

This document reports the radiological characterization of various versions of surge arresters used in the past to protect telephone lines against over-voltages. These equipment, which use various radioactive materials, were assessed by gamma radiation flow measurements, alpha-beta-gamma count rate measurements, dose rate measurements, gamma spectrometry analyses, tritium emanation test, radon 222 emanation test, smearing. Recommendations are formulated to manage radioactive surge arresters which are still being operated

Role of biodiesel-diesel blends in alteration of particulate matter emanated by diesel engine

International Nuclear Information System (INIS)

Shah, A.N.; Shahid, E.M.

2015-01-01

The current study is focused on the investigation of the role of biodiesel in the alteration of particulate matter (PM) composition emitted from a direct injection-compression ignition. Two important blends of biodiesel with commercial diesel known as B20 (20% biodiesel and 80% diesel by volume) and B50 were used for the comparative analysis of their pollutants with those of 100% or traditional diesel (D). The experiments were performed under the auspices of the Chinese 8-mode steady-state cycle on a test bench by coupling the engine with an AC electrical dynamometer. As per experimental results, over-50 nm aerosols were abated by 8.7-47% and 6-51% with B20 and B50, respectively, on account of lofty nitrogen dioxide to nitrogen oxides (NO2/NO) ratios. In case of B50, sub-50 nm aerosols and sulphates were higher at maximum load modes of the test, owing to adsorption phenomenon of inorganic nuclei leading to heterogeneous nucleation. Moreover, trace metal emissions (TME) were substantially reduced reflecting the reduction rates of 42-57% and 64-80% with B20 and B50, respectively, relative to baseline measurements taken with diesel. In addition to this, individual elements such as Ca and Fe were greatly minimised, while Na was enhanced with biodiesel blended fuels. (author)

Data compilation of respiration, feeding, and growth rates of marine pelagic organisms

DEFF Research Database (Denmark)

2013-01-01

's adaptation to the environment, with consequently less universal mass scaling properties. Data on body mass, maximum ingestion and clearance rates, respiration rates and maximum growth rates of animals living in the ocean epipelagic were compiled from the literature, mainly from original papers but also from...

Maximum total organic carbon limit for DWPF melter feed

International Nuclear Information System (INIS)

Choi, A.S.

1995-01-01

DWPF recently decided to control the potential flammability of melter off-gas by limiting the total carbon content in the melter feed and maintaining adequate conditions for combustion in the melter plenum. With this new strategy, all the LFL analyzers and associated interlocks and alarms were removed from both the primary and backup melter off-gas systems. Subsequently, D. Iverson of DWPF- T ampersand E requested that SRTC determine the maximum allowable total organic carbon (TOC) content in the melter feed which can be implemented as part of the Process Requirements for melter feed preparation (PR-S04). The maximum TOC limit thus determined in this study was about 24,000 ppm on an aqueous slurry basis. At the TOC levels below this, the peak concentration of combustible components in the quenched off-gas will not exceed 60 percent of the LFL during off-gas surges of magnitudes up to three times nominal, provided that the melter plenum temperature and the air purge rate to the BUFC are monitored and controlled above 650 degrees C and 220 lb/hr, respectively. Appropriate interlocks should discontinue the feeding when one or both of these conditions are not met. Both the magnitude and duration of an off-gas surge have a major impact on the maximum TOC limit, since they directly affect the melter plenum temperature and combustion. Although the data obtained during recent DWPF melter startup tests showed that the peak magnitude of a surge can be greater than three times nominal, the observed duration was considerably shorter, on the order of several seconds. The long surge duration assumed in this study has a greater impact on the plenum temperature than the peak magnitude, thus making the maximum TOC estimate conservative. Two models were used to make the necessary calculations to determine the TOC limit

Maximum Gene-Support Tree

Directory of Open Access Journals (Sweden)

Yunfeng Shan

2008-01-01

Full Text Available Genomes and genes diversify during evolution; however, it is unclear to what extent genes still retain the relationship among species. Model species for molecular phylogenetic studies include yeasts and viruses whose genomes were sequenced as well as plants that have the fossil-supported true phylogenetic trees available. In this study, we generated single gene trees of seven yeast species as well as single gene trees of nine baculovirus species using all the orthologous genes among the species compared. Homologous genes among seven known plants were used for validation of the finding. Four algorithms—maximum parsimony (MP, minimum evolution (ME, maximum likelihood (ML, and neighbor-joining (NJ—were used. Trees were reconstructed before and after weighting the DNA and protein sequence lengths among genes. Rarely a gene can always generate the “true tree” by all the four algorithms. However, the most frequent gene tree, termed “maximum gene-support tree” (MGS tree, or WMGS tree for the weighted one, in yeasts, baculoviruses, or plants was consistently found to be the “true tree” among the species. The results provide insights into the overall degree of divergence of orthologous genes of the genomes analyzed and suggest the following: 1 The true tree relationship among the species studied is still maintained by the largest group of orthologous genes; 2 There are usually more orthologous genes with higher similarities between genetically closer species than between genetically more distant ones; and 3 The maximum gene-support tree reflects the phylogenetic relationship among species in comparison.

Gender-specific feeding rates in planktonic copepods with different feeding behavior

DEFF Research Database (Denmark)

van Someren Gréve, Hans; Almeda, Rodrigo; Lindegren, Martin

2017-01-01

Planktonic copepods have sexually dimorphic behaviors, which can cause differences in feeding efficiency between genders. Copepod feeding rates have been studied extensively but most studies have focused only on females. In this study, we experimentally quantified feeding rates of males and females...... copepods, particularly in ambush feeders, where the males must sacrifice feeding for mate searching. We conducted gender-specific functional feeding response experiments using prey of different size and motility. In most cases, gender-specific maximum ingestion and clearance rates were largely explained...... in copepods with different feeding behavior: ambush feeding (Oithona nana), feeding-current feeding (Temora longicornis) and cruising feeding (Centropages hamatus). We hypothesize that carbon-specific maximum ingestion rates are similar between genders, but that maximum clearance rates are lower for male...

Maximum Throughput in a C-RAN Cluster with Limited Fronthaul Capacity

OpenAIRE

Duan , Jialong; Lagrange , Xavier; Guilloud , Frédéric

2016-01-01

International audience; Centralized/Cloud Radio Access Network (C-RAN) is a promising future mobile network architecture which can ease the cooperation between different cells to manage interference. However, the feasibility of C-RAN is limited by the large bit rate requirement in the fronthaul. This paper study the maximum throughput of different transmission strategies in a C-RAN cluster with transmission power constraints and fronthaul capacity constraints. Both transmission strategies wit...

Maximum neutron flux in thermal reactors

International Nuclear Information System (INIS)

Strugar, P.V.

1968-12-01

Direct approach to the problem is to calculate spatial distribution of fuel concentration if the reactor core directly using the condition of maximum neutron flux and comply with thermal limitations. This paper proved that the problem can be solved by applying the variational calculus, i.e. by using the maximum principle of Pontryagin. Mathematical model of reactor core is based on the two-group neutron diffusion theory with some simplifications which make it appropriate from maximum principle point of view. Here applied theory of maximum principle are suitable for application. The solution of optimum distribution of fuel concentration in the reactor core is obtained in explicit analytical form. The reactor critical dimensions are roots of a system of nonlinear equations and verification of optimum conditions can be done only for specific examples

Excess Readmission vs Excess Penalties: Maximum Readmission Penalties as a Function of Socioeconomics and Geography.

Science.gov (United States)

Caracciolo, Chris; Parker, Devin; Marshall, Emily; Brown, Jeremiah

2017-08-01

The Hospital Readmission Reduction Program (HRRP) penalizes hospitals with "excess" readmissions up to 3% of Medicare reimbursement. Approximately 75% of eligible hospitals received penalties, worth an estimated $428 million, in fiscal year 2015. To identify demographic and socioeconomic disparities between matched and localized maximum-penalty and no-penalty hospitals. A case-control study in which cases included were hospitals to receive the maximum 3% penalty under the HRRP during the 2015 fiscal year. Controls were drawn from no-penalty hospitals and matched to cases by hospital characteristics (primary analysis) or geographic proximity (secondary analysis). A selectiion of 3383 US hospitals eligible for HRRP. Thirty-nine case and 39 control hospitals from the HRRP cohort. Socioeconomic status variables were collected by the American Community Survey. Hospital and health system characteristics were drawn from Centers for Medicare and Medicaid Services, American Hospital Association, and Dartmouth Atlas of Health Care. The statistical analysis was conducted using Student t tests. Thirty-nine hospitals received a maximum penalty. Relative to controls, maximum-penalty hospitals in counties with lower SES profiles are defined by increased poverty rates (19.1% vs 15.5%, = 0.015) and lower rates of high school graduation (82.2% vs 87.5%, = 0.001). County level age, sex, and ethnicity distributions were similar between cohorts. Cases were more likely than controls to be in counties with low socioeconomic status; highlighting potential unintended consequences of national benchmarks for phenomena underpinned by environmental factors; specifically, whether maximum penalties under the HRRP are a consequence of underperforming hospitals or a manifestation of underserved communities. © 2017 Society of Hospital Medicine

Measurement of 222Rn and 220Rn exhalation rate from soil samples of Kumaun Hills, India

Science.gov (United States)

Semwal, Poonam; Singh, Kuldeep; Agarwal, T. K.; Joshi, Manish; Pant, Preeti; Kandari, Tushar; Ramola, R. C.

2018-03-01

The source terms, i.e., exhalation and emanation from soil and building materials are the primary contributors to the radon (222Rn)/thoron (220Rn) concentration levels in the dwellings, while the ecological constraints like ventilation rate, temperature, pressure, humidity, etc., are the influencing factors. The present study is focused on Almora District of Kumaun, located in Himalayan belt of Uttarakhand, India. For the measurement of 222Rn and 220Rn exhalation rates, 24 soil samples were collected from different locations. Gamma radiation level was measured at each of these locations. Chamber technique associated with Smart Rn Duo portable monitor was employed for the estimation of 222Rn and 220Rn exhalation rates. Radionuclides (226Ra, 232Th and 40K) concentrations were also measured in soil samples using NaI(Tl) scintillation based gamma ray spectrometry. The mass exhalation rate for 222Rn was varying between 16 and 54 mBq/kg/h, while the 220Rn surface exhalation rate was in the range of 0.65-6.43 Bq/m2/s. Measured gamma dose rate for the same region varied from 0.10 to 0.31 µSv/h. Inter-correlation of exhalation rates and intra-correlation with background gamma levels were studied.

The effects of a pilates-aerobic program on maximum exercise capacity of adult women

Directory of Open Access Journals (Sweden)

Milena Mikalački

Full Text Available ABSTRACT Introduction: Physical exercise such as the Pilates method offers clinical benefits on the aging process. Likewise, physiologic parameters may be improved through aerobic exercise. Methods: In order to compare the differences of a Pilates-Aerobic intervention program on physiologic parameters such as the maximum heart rate (HRmax, relative maximal oxygen consumption (relative VO2max and absolute (absolute VOmax, maximum heart rate during maximal oxygen consumption (VO2max-HRmax, maximum minute volume (VE and forced vital capacity (FVC, a total of 64 adult women (active group = 48.1 ± 6.7 years; control group = 47.2 ± 7.4 years participated in the study. The physiological parameters, the maximal speed and total duration of test were measured by maximum exercise capacity testing through Bruce protocol. The HRmax was calculated by a cardio-ergometric software. Pulmonary function tests, maximal speed and total time during the physical test were performed in a treadmill (Medisoft, model 870c. Likewise, the spirometry analyzed the impact on oxygen uptake parameters, including FVC and VE. Results: The VO2max (relative and absolute, VE (all, P<0.001, VO2max-HRmax (P<0.05 and maximal speed of treadmill test (P<0.001 showed significant difference in the active group after a physical exercise interventional program. Conclusion: The present study indicates that the Pilates exercises through a continuous training program might significantly improve the cardiovascular system. Hence, mixing strength and aerobic exercises into a training program is considered the optimal mechanism for healthy aging.

Experimental technique to measure thoron generation rate of building material samples using RAD7 detector

International Nuclear Information System (INIS)

Csige, I.; Szabó, Zs.; Szabó, Cs.

2013-01-01

Thoron ( 220 Rn) is the second most abundant radon isotope in our living environment. In some dwellings it is present in significant amount which calls for its identification and remediation. Indoor thoron originates mainly from building materials. In this work we have developed and tested an experimental technique to measure thoron generation rate in building material samples using RAD7 radon-thoron detector. The mathematical model of the measurement technique provides the thoron concentration response of RAD7 as a function of the sample thickness. For experimental validation of the technique an adobe building material sample was selected for measuring the thoron concentration at nineteen different sample thicknesses. Fitting the parameters of the model to the measurement results, both the generation rate and the diffusion length of thoron was estimated. We have also determined the optimal sample thickness for estimating the thoron generation rate from a single measurement. -- Highlights: • RAD7 is used for the determination of thoron generation rate (emanation). • The described model takes into account the thoron decay and attenuation. • The model describes well the experimental results. • A single point measurement method is offered at a determined sample thickness

Adoption of the American Academy of Pediatrics’ neonatal hyperbilirubinemia guidelines and its effect on blood exchange transfusion rate in a tertiary care center in Amman, Jordan

OpenAIRE

Al-Lawama M; Al-Rimawi E; Al-Shibi R; Badran E

2018-01-01

Manar Al-Lawama, Eman Al-Rimawi, Rawan Al-Shibi, Eman Badran Department of Pediatrics, The University of Jordan, School of Medicine, Amman, Jordan Introduction: Severe neonatal hyperbilirubinemia can cause mortality and serious morbidities. When phototherapy fails, neonates with severe hyperbilirubinemia should undergo double volume blood exchange transfusion (BET). As this procedure carries a significant risk of mortality and morbidity, adopting guidelines for the ...

75 FR 43840 - Inflation Adjustment of the Ordinary Maximum and Aggravated Maximum Civil Monetary Penalties for...

Science.gov (United States)

2010-07-27

...-17530; Notice No. 2] RIN 2130-ZA03 Inflation Adjustment of the Ordinary Maximum and Aggravated Maximum... remains at $250. These adjustments are required by the Federal Civil Penalties Inflation Adjustment Act [email protected] . SUPPLEMENTARY INFORMATION: The Federal Civil Penalties Inflation Adjustment Act of 1990...

Half-width at half-maximum, full-width at half-maximum analysis

Indian Academy of Sciences (India)

addition to the well-defined parameter full-width at half-maximum (FWHM). The distribution of ... optical side-lobes in the diffraction pattern resulting in steep central maxima [6], reduc- tion of effects of ... and broad central peak. The idea of.

Two-dimensional maximum entropy image restoration

International Nuclear Information System (INIS)

Brolley, J.E.; Lazarus, R.B.; Suydam, B.R.; Trussell, H.J.

1977-07-01

An optical check problem was constructed to test P LOG P maximum entropy restoration of an extremely distorted image. Useful recovery of the original image was obtained. Comparison with maximum a posteriori restoration is made. 7 figures

76 FR 53134 - Maximum Per Diem Rates for the Continental United States (CONUS)

Science.gov (United States)

2011-08-25

... in the per diem rate setting process enhances the Government's ability to obtain policy-compliant...-standard area (NSA): Alexandria/Leesville/Natchitoches, Louisiana (Allen, Jefferson Davis, Natchitoches... the standard CONUS designation in FY 2011. Of those locations, the following areas will once again...

Debris prevention system, radiation system, and lithograpic apparatus

NARCIS (Netherlands)

2009-01-01

A debris prevention system is constructed and arranged to prevent debris that emanates from a radiation source from propagating with radiation from the radiation source into or within a lithographic apparatus. The debris prevention system includes an aperture that defines a maximum emission angle of

Heart rate monitoring mobile applications

OpenAIRE

Chaudhry, Beenish M.

2016-01-01

Total number of times a heart beats in a minute is known as the heart rate. Traditionally, heart rate was measured using clunky gadgets but these days it can be measured with a smartphone?s camera. This can help you measure your heart rate anywhere and at anytime, especially during workouts so you can adjust your workout intensity to achieve maximum health benefits. With simple and easy to use mobile app, ?Unique Heart Rate Monitor?, you can also maintain your heart rate history for personal ...

Instantaneous global nitrous oxide photochemical rates

International Nuclear Information System (INIS)

Johnston, H.S.; Serang, O.; Podolske, J.

1979-01-01

In recent years, vertical profiles of nitrous oxide have been measured by balloon up to midstratosphere at several latitudes between 63 0 N and 73 0 S, including one profile in the tropical zone at 9 0 N. Two rocket flights measured nitrous oxide mixing ratios at 44 and 49 km. From these experimental data plus a large amount of interpolation and extrapolation, we have estimated a global distribution of nitrous oxide up to the altitude of 50 km. With standard global distributions of oxygen and ozone we carried out instantaneous, three-dimensional, global photochemical calculations, using recently measured temperature-dependent cross sections for nitrous oxide. The altitude of maximum photolysis rate of N 2 O is about 30 km at all latitudes, and the rate of photolysis is a maximum in tropical latitudes. The altitude of maximum rate of formation of nitric oxide is latitude dependent, about 26 km at the equator, about 23 km over temperate zones, and 20 km at the summer pole. The global rate of N 2 O destruction is 6.2 x 10 27 molecules s -1 , and the global rate of formation of NO from N 2 O is 1.4 x 10 27 molecules s -1 . The global N 2 O inventory divided by the stratospheric loss rate gives a residence time of about 175 years with respect to this loss process. From the global average N 2 O profile a vertical eddy diffusion profile was derived, and this profile agrees very closely with that of Stewart and Hoffert

A Modified Levenberg-Marquardt Method for Nonsmooth Equations with Finitely Many Maximum Functions

Directory of Open Access Journals (Sweden)

Shou-qiang Du

2008-01-01

Full Text Available For solving nonsmooth systems of equations, the Levenberg-Marquardt method and its variants are of particular importance because of their locally fast convergent rates. Finitely many maximum functions systems are very useful in the study of nonlinear complementarity problems, variational inequality problems, Karush-Kuhn-Tucker systems of nonlinear programming problems, and many problems in mechanics and engineering. In this paper, we present a modified Levenberg-Marquardt method for nonsmooth equations with finitely many maximum functions. Under mild assumptions, the present method is shown to be convergent Q-linearly. Some numerical results comparing the proposed method with classical reformulations indicate that the modified Levenberg-Marquardt algorithm works quite well in practice.

CHARACTERISTICS OF MAXIMUM PERFORMANCE OF PEDALING EXERCISE IN RECUMBENT AND SUPINE POSITIONS

Directory of Open Access Journals (Sweden)

Morimasa Kato

2011-09-01

Full Text Available To determine the characteristics of maximum pedaling performance in the recumbent and supine positions, maximum isokinetic leg muscle strength was measured in eight healthy male subjects during pedaling at three velocities (300°/s, 480°/s, and 660°/s, and maximum incremental tests were performed for each position. The maximum isokinetic muscle strength in the recumbent position was 210.0 ± 29.2 Nm at 300°/s, 158.4 ± 19.8 Nm at 480°/s, and 110.6 ± 13.2 at 660°/s. In contrast, the muscle strength in the supine position was 229.3 ± 36.7 Nm at 300°/s, 180. 7 ± 20.3 Nm at 480°/s, and 129.6 ± 14.0 Nm at 660°/s. Thus, the maximum isokinetic muscle strength showed significantly higher values in the supine position than in the recumbent position at all angular velocities. The knee and hip joint angles were measured at peak torque using a goniometer; the knee joint angle was not significantly different between both positions, whereas the hip joint angle was greater in the supine position than in the recumbent position (Supine position: 137.3 ± 9. 33 degree at 300°/s, 140.0 ± 11.13 degrees at 480°/s, and 141.0 ± 9.61 degrees at 660°/s. Recumbent position: 99.5 ± 12.21 degrees at 300°/s, 101.6 ± 12.29 degrees at 480°/s, and 105.8 ± 14.28 degrees at 660°/s. Peak oxygen uptake was higher in the recumbent position (50.3 ± 4.43 ml·kg-1·min-1 than in the supine position (48.7 ± 5.10 ml·kg-1·min-1. At maximum exertion, the heart rate and whole-body rate of perceived exertion (RPE were unaffected by position, but leg muscle RPE was higher in the supine position (19.5 ± 0.53 than in the recumbent position (18.8 ± 0.71. These results suggest that the supine position is more suitable for muscle strength exertion than the recumbent position, and this may be due to different hip joint angles between the positions. On the contrary, the endurance capacity was higher in the recumbent position than in the supine position. Since leg muscle

MXLKID: a maximum likelihood parameter identifier

International Nuclear Information System (INIS)

Gavel, D.T.

1980-07-01

MXLKID (MaXimum LiKelihood IDentifier) is a computer program designed to identify unknown parameters in a nonlinear dynamic system. Using noisy measurement data from the system, the maximum likelihood identifier computes a likelihood function (LF). Identification of system parameters is accomplished by maximizing the LF with respect to the parameters. The main body of this report briefly summarizes the maximum likelihood technique and gives instructions and examples for running the MXLKID program. MXLKID is implemented LRLTRAN on the CDC7600 computer at LLNL. A detailed mathematical description of the algorithm is given in the appendices. 24 figures, 6 tables

Does shoe heel design influence ground reaction forces and knee moments during maximum lunges in elite and intermediate badminton players?

Directory of Open Access Journals (Sweden)

Wing-Kai Lam

Full Text Available Lunge is one frequently executed movement in badminton and involves a unique sagittal footstrike angle of more than 40 degrees at initial ground contact compared with other manoeuvres. This study examined if the shoe heel curvature design of a badminton shoe would influence shoe-ground kinematics, ground reaction forces, and knee moments during lunge.Eleven elite and fifteen intermediate players performed five left-forward maximum lunge trials with Rounded Heel Shoe (RHS, Flattened Heel Shoe (FHS, and Standard Heel Shoes (SHS. Shoe-ground kinematics, ground reaction forces, and knee moments were measured by using synchronized force platform and motion analysis system. A 2 (Group x 3 (Shoe ANOVA with repeated measures was performed to determine the effects of different shoes and different playing levels, as well as the interaction of two factors on all variables.Shoe effect indicated that players demonstrated lower maximum vertical loading rate in RHS than the other two shoes (P < 0.05. Group effect revealed that elite players exhibited larger footstrike angle, faster approaching speed, lower peak horizontal force and horizontal loading rates but higher vertical loading rates and larger peak knee flexion and extension moments (P < 0.05. Analysis of Interactions of Group x Shoe for maximum and mean vertical loading rates (P < 0.05 indicated that elite players exhibited lower left maximum and mean vertical loading rates in RHS compared to FHS (P < 0.01, while the intermediate group did not show any Shoe effect on vertical loading rates.These findings indicate that shoe heel curvature would play some role in altering ground reaction force impact during badminton lunge. The differences in impact loads and knee moments between elite and intermediate players may be useful in optimizing footwear design and training strategy to minimize the potential risks for impact related injuries in badminton.

Measurement of Strain and Strain Rate during the Impact of Tennis Ball Cores

Directory of Open Access Journals (Sweden)

Ben Lane

2018-03-01

Full Text Available The aim of this investigation was to establish the strains and strain rates experienced by tennis ball cores during impact to inform material characterisation testing and finite element modelling. Three-dimensional surface strains and strain rates were measured using two high-speed video cameras and corresponding digital image correlation software (GOM Correlate Professional. The results suggest that material characterisation testing to a maximum strain of 0.4 and a maximum rate of 500 s−1 in tension and to a maximum strain of −0.4 and a maximum rate of −800 s−1 in compression would encapsulate the demands placed on the material during impact and, in turn, define the range of properties required to encapsulate the behavior of the material during impact, enabling testing to be application-specific and strain-rate-dependent properties to be established and incorporated in finite element models.

Optimal operating conditions for maximum biogas production in anaerobic bioreactors

International Nuclear Information System (INIS)

Balmant, W.; Oliveira, B.H.; Mitchell, D.A.; Vargas, J.V.C.; Ordonez, J.C.

2014-01-01

The objective of this paper is to demonstrate the existence of optimal residence time and substrate inlet mass flow rate for maximum methane production through numerical simulations performed with a general transient mathematical model of an anaerobic biodigester introduced in this study. It is herein suggested a simplified model with only the most important reaction steps which are carried out by a single type of microorganisms following Monod kinetics. The mathematical model was developed for a well mixed reactor (CSTR – Continuous Stirred-Tank Reactor), considering three main reaction steps: acidogenesis, with a μ max of 8.64 day −1 and a K S of 250 mg/L, acetogenesis, with a μ max of 2.64 day −1 and a K S of 32 mg/L, and methanogenesis, with a μ max of 1.392 day −1 and a K S of 100 mg/L. The yield coefficients were 0.1-g-dry-cells/g-pollymeric compound for acidogenesis, 0.1-g-dry-cells/g-propionic acid and 0.1-g-dry-cells/g-butyric acid for acetogenesis and 0.1 g-dry-cells/g-acetic acid for methanogenesis. The model describes both the transient and the steady-state regime for several different biodigester design and operating conditions. After model experimental validation, a parametric analysis was performed. It was found that biogas production is strongly dependent on the input polymeric substrate and fermentable monomer concentrations, but fairly independent of the input propionic, acetic and butyric acid concentrations. An optimisation study was then conducted and optimal residence time and substrate inlet mass flow rate were found for maximum methane production. The optima found were very sharp, showing a sudden drop of methane mass flow rate variation from the observed maximum to zero, within a 20% range around the optimal operating parameters, which stresses the importance of their identification, no matter how complex the actual bioreactor design may be. The model is therefore expected to be a useful tool for simulation, design, control and

Heart rate monitoring mobile applications.

Science.gov (United States)

Chaudhry, Beenish M

2016-01-01

Total number of times a heart beats in a minute is known as the heart rate. Traditionally, heart rate was measured using clunky gadgets but these days it can be measured with a smartphone's camera. This can help you measure your heart rate anywhere and at anytime, especially during workouts so you can adjust your workout intensity to achieve maximum health benefits. With simple and easy to use mobile app, 'Unique Heart Rate Monitor', you can also maintain your heart rate history for personal reflection and sharing with a provider.

Potential transport pathways of dust emanating from the playa of Ebinur Lake, Xinjiang, in arid northwest China

Science.gov (United States)

Ge, Yongxiao; Abuduwaili, Jilili; Ma, Long; Wu, Na; Liu, Dongwei

2016-09-01

In this paper, the HYSPLIT model, driven with reanalysis meteorological data from 1978 to 2013, was used to understand the potential transport characteristics of dust and salt dust emanating from the playa of Ebinur Lake in arid northwest China. Daily air parcel trajectories were computed forward for 8 days from an origin centered over Ebinur Lake at 100 m above ground level. Air parcel trajectory density plots were mapped for seven levels: 0-100 m agl., 100-500 m agl., 500-1000 m agl., 1000-1500 m agl., 1500-2000 m agl., 2000-3000 m agl., and 3000-5000 m agl. These show that potential dust transport pathways have clear seasonal differentiation. The potential transport distance of dust and salt dust is greatest in spring and summer. In autumn and winter, the potential transport of the high-density air trajectory is below 1000 m traveling a shorter distance. Potential dust transport pathways showed notifying directivity in different seasons and heights. Southeast in spring and summer, and north to northeast in autumn and winter are the two main potential transport channels of dust and salt dust. Accordingly, dust and salt dust from the playa of Ebinur Lake may influence the atmospheric processes and biogeochemical cycles of a vast region. The main area of influence of dust and salt dust is close to the source area, and will significantly accelerate the melting of snow and ice in the Tianshan Mountains. This highlights the urgent need to combine remote sensing, isotope and other methods to further research the transport characteristics of dust and salt dust from the playa of the Ebinur Lake.

Standard values of maximum tongue pressure taken using newly developed disposable tongue pressure measurement device.

Science.gov (United States)

Utanohara, Yuri; Hayashi, Ryo; Yoshikawa, Mineka; Yoshida, Mitsuyoshi; Tsuga, Kazuhiro; Akagawa, Yasumasa

2008-09-01

It is clinically important to evaluate tongue function in terms of rehabilitation of swallowing and eating ability. We have developed a disposable tongue pressure measurement device designed for clinical use. In this study we used this device to determine standard values of maximum tongue pressure in adult Japanese. Eight hundred fifty-three subjects (408 male, 445 female; 20-79 years) were selected for this study. All participants had no history of dysphagia and maintained occlusal contact in the premolar and molar regions with their own teeth. A balloon-type disposable oral probe was used to measure tongue pressure by asking subjects to compress it onto the palate for 7 s with maximum voluntary effort. Values were recorded three times for each subject, and the mean values were defined as maximum tongue pressure. Although maximum tongue pressure was higher for males than for females in the 20-49-year age groups, there was no significant difference between males and females in the 50-79-year age groups. The maximum tongue pressure of the seventies age group was significantly lower than that of the twenties to fifties age groups. It may be concluded that maximum tongue pressures were reduced with primary aging. Males may become weaker with age at a faster rate than females; however, further decreases in strength were in parallel for male and female subjects.

78 FR 9845 - Minimum and Ordinary Maximum and Aggravated Maximum Civil Monetary Penalties for a Violation of...

Science.gov (United States)

2013-02-12

... maximum penalty amount of $75,000 for each violation, except that if the violation results in death... the maximum civil penalty for a violation is $175,000 if the violation results in death, serious... Penalties for a Violation of the Hazardous Materials Transportation Laws or Regulations, Orders, Special...

12 CFR 619.9170 - Fixed interest rate.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Fixed interest rate. 619.9170 Section 619.9170 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM DEFINITIONS § 619.9170 Fixed interest rate. The rate of interest specified in the note or loan document which will prevail as the maximum...

Performance analysis and comparison of an Atkinson cycle coupled to variable temperature heat reservoirs under maximum power and maximum power density conditions

International Nuclear Information System (INIS)

Wang, P.-Y.; Hou, S.-S.

2005-01-01

In this paper, performance analysis and comparison based on the maximum power and maximum power density conditions have been conducted for an Atkinson cycle coupled to variable temperature heat reservoirs. The Atkinson cycle is internally reversible but externally irreversible, since there is external irreversibility of heat transfer during the processes of constant volume heat addition and constant pressure heat rejection. This study is based purely on classical thermodynamic analysis methodology. It should be especially emphasized that all the results and conclusions are based on classical thermodynamics. The power density, defined as the ratio of power output to maximum specific volume in the cycle, is taken as the optimization objective because it considers the effects of engine size as related to investment cost. The results show that an engine design based on maximum power density with constant effectiveness of the hot and cold side heat exchangers or constant inlet temperature ratio of the heat reservoirs will have smaller size but higher efficiency, compression ratio, expansion ratio and maximum temperature than one based on maximum power. From the view points of engine size and thermal efficiency, an engine design based on maximum power density is better than one based on maximum power conditions. However, due to the higher compression ratio and maximum temperature in the cycle, an engine design based on maximum power density conditions requires tougher materials for engine construction than one based on maximum power conditions

Accuracy of maximum likelihood estimates of a two-state model in single-molecule FRET

Energy Technology Data Exchange (ETDEWEB)

Gopich, Irina V. [Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892 (United States)

2015-01-21

Photon sequences from single-molecule Förster resonance energy transfer (FRET) experiments can be analyzed using a maximum likelihood method. Parameters of the underlying kinetic model (FRET efficiencies of the states and transition rates between conformational states) are obtained by maximizing the appropriate likelihood function. In addition, the errors (uncertainties) of the extracted parameters can be obtained from the curvature of the likelihood function at the maximum. We study the standard deviations of the parameters of a two-state model obtained from photon sequences with recorded colors and arrival times. The standard deviations can be obtained analytically in a special case when the FRET efficiencies of the states are 0 and 1 and in the limiting cases of fast and slow conformational dynamics. These results are compared with the results of numerical simulations. The accuracy and, therefore, the ability to predict model parameters depend on how fast the transition rates are compared to the photon count rate. In the limit of slow transitions, the key parameters that determine the accuracy are the number of transitions between the states and the number of independent photon sequences. In the fast transition limit, the accuracy is determined by the small fraction of photons that are correlated with their neighbors. The relative standard deviation of the relaxation rate has a “chevron” shape as a function of the transition rate in the log-log scale. The location of the minimum of this function dramatically depends on how well the FRET efficiencies of the states are separated.

Methodology for determination of radon-222 production rate of residential building and experimental verification

International Nuclear Information System (INIS)

Tung, Thomas C.W.; Niu, J.L.; Burnett, J.; Lau, Judy O.W.

2005-01-01

Indoor radon concentration is mainly associated with the radon production rate of building material, ventilation rate, and the outdoor radon concentrations. Radon production rate of a room is defined as the sum of the products of the radon emanation rates and the exposed areas of the materials. Since the selection of the building materials and the exposed areas are different from room to room, it makes the radon production rate of homes fall in a wide range. Here, the radon production rate of a room is suggested to be quantified by a sealing method, in which the systematic radon growth curve is obtained. The radon production rate of the room can be determined from the initial slope of the growth curve. Three rooms at different homes in Hong Kong were selected in the study for verifying the methodology. The uncertainty characterized by data scatter arisen from the coupling effect of the leakage rate and outdoor radon was also included in the discussion. During the measurements, no occupant was allowed into the home. No mechanical ventilation was involved in the measurement. The indoor and outdoor radon concentrations of the sampled homes were monitored simultaneously and lasted for more than three days. The radon production rates and the uncertainties of three rooms at Homes 1, 2, and 3 were found to be 232.8, 46.0, 414.6, and 20.3, 9.4, 59.2Bqh -1 , respectively. The approach is valid when the air leakage rate of the room is controlled below 0.1h -1

Analytical methods of leakage rate estimation from a containment under a LOCA

International Nuclear Information System (INIS)

Chun, M.H.

1981-01-01

Three most outstanding maximum flow rate formulas are identified from many existing models. Outlines of the three limiting mass flow rate models are given along with computational procedures to estimate approximate amount of fission products released from a containment to environment for a given characteristic hole size for containment-isolation failure and containment pressure and temperature under a loss of coolant accident. Sample calculations are performed using the critical ideal gas flow rate model and the Moody's graphs for the maximum two-phase flow rates, and the results are compared with the values obtained from then mass leakage rate formula of CONTEMPT-LT code for converging nozzle and sonic flow. It is shown that the critical ideal gas flow rate formula gives almost comparable results as one can obtain from the Moody's model. It is also found that a more conservative approach to estimate leakage rate from a containment under a LOCA is to use the maximum ideal gas flow rate equation rather than the mass leakage rate formula of CONTEMPT-LT. (author)

What if the Diatoms of the Deep Chlorophyll Maximum Can Ascend?

Science.gov (United States)

Villareal, T. A.

2016-02-01

Buoyancy regulation is an integral part of diatom ecology via its role in sinking rates and is fundamental to understanding their distribution and abundance. Numerous studies have documented the effects of size and nutrition on sinking rates. Many pelagic diatoms have low intrinsic sinking rates when healthy and nutrient-replete (deep chlorophyll maximum. The potential for ascending behavior adds an additional layer of complexity by allowing both active depth regulation similar to that observed in flagellated taxa and upward transport by some fraction of deep euphotic zone diatom blooms supported by nutrient injection. In this talk, I review the data documenting positive buoyancy in small diatoms, offer direct visual evidence of ascending behavior in common diatoms typical of both oceanic and coastal zones, and note the characteristics of sinking rate distributions within a single species. Buoyancy control leads to bidirectional movement at similar rates across a wide size spectrum of diatoms although the frequency of ascending behavior may be only a small portion of the individual species' abundance. While much remains to be learned, the paradigm of unidirectional downward movement by diatoms is both inaccurate and an oversimplification.

The eukaryotic bell-shaped temporal rate of DNA replication origin firing emanates from a balance between origin activation and passivation.

Science.gov (United States)

Arbona, Jean-Michel; Goldar, Arach; Hyrien, Olivier; Arneodo, Alain; Audit, Benjamin

2018-06-01

The time-dependent rate I(t) of origin firing per length of unreplicated DNA presents a universal bell shape in eukaryotes that has been interpreted as the result of a complex time-evolving interaction between origins and limiting firing factors. Here we show that a normal diffusion of replication fork components towards localized potential replication origins (p-oris) can more simply account for the I(t) universal bell shape, as a consequence of a competition between the origin firing time and the time needed to replicate DNA separating two neighboring p-oris . We predict the I(t) maximal value to be the product of the replication fork speed with the squared p-ori density. We show that this relation is robustly observed in simulations and in experimental data for several eukaryotes. Our work underlines that fork-component recycling and potential origins localization are sufficient spatial ingredients to explain the universality of DNA replication kinetics. © 2018, Arbona et al.

Paddle River Dam : review of probable maximum flood

Energy Technology Data Exchange (ETDEWEB)

Clark, D. [UMA Engineering Ltd., Edmonton, AB (Canada); Neill, C.R. [Northwest Hydraulic Consultants Ltd., Edmonton, AB (Canada)

2008-07-01

The Paddle River Dam was built in northern Alberta in the mid 1980s for flood control. According to the 1999 Canadian Dam Association (CDA) guidelines, this 35 metre high, zoned earthfill dam with a spillway capacity sized to accommodate a probable maximum flood (PMF) is rated as a very high hazard. At the time of design, it was estimated to have a peak flow rate of 858 centimetres. A review of the PMF in 2002 increased the peak flow rate to 1,890 centimetres. In light of a 2007 revision of the CDA safety guidelines, the PMF was reviewed and the inflow design flood (IDF) was re-evaluated. This paper discussed the levels of uncertainty inherent in PMF determinations and some difficulties encountered with the SSARR hydrologic model and the HEC-RAS hydraulic model in unsteady mode. The paper also presented and discussed the analysis used to determine incremental damages, upon which a new IDF of 840 m{sup 3}/s was recommended. The paper discussed the PMF review, modelling methodology, hydrograph inputs, and incremental damage of floods. It was concluded that the PMF review, involving hydraulic routing through the valley bottom together with reconsideration of the previous runoff modeling provides evidence that the peak reservoir inflow could reasonably be reduced by approximately 20 per cent. 8 refs., 5 tabs., 8 figs.

LCLS Maximum Credible Beam Power

International Nuclear Information System (INIS)

Clendenin, J.

2005-01-01

The maximum credible beam power is defined as the highest credible average beam power that the accelerator can deliver to the point in question, given the laws of physics, the beam line design, and assuming all protection devices have failed. For a new accelerator project, the official maximum credible beam power is determined by project staff in consultation with the Radiation Physics Department, after examining the arguments and evidence presented by the appropriate accelerator physicist(s) and beam line engineers. The definitive parameter becomes part of the project's safety envelope. This technical note will first review the studies that were done for the Gun Test Facility (GTF) at SSRL, where a photoinjector similar to the one proposed for the LCLS is being tested. In Section 3 the maximum charge out of the gun for a single rf pulse is calculated. In Section 4, PARMELA simulations are used to track the beam from the gun to the end of the photoinjector. Finally in Section 5 the beam through the matching section and injected into Linac-1 is discussed

Parametric characteristics of a solar thermophotovoltaic system at the maximum efficiency

International Nuclear Information System (INIS)

Liao, Tianjun; Chen, Xiaohang; Yang, Zhimin; Lin, Bihong; Chen, Jincan

2016-01-01

Graphical abstract: A model of the far-field TPVC driven by solar energy, which consists of an optical concentrator, an absorber, an emitter, and a PV cell and is simply referred as to the far-field STPVS. - Highlights: • A model of the far-field solar thermophotovoltaic system (STPVS) is established. • External and internal irreversible losses are considered. • The maximum efficiency of the STPVS is calculated. • Optimal values of key parameters at the maximum efficiency are determined. • Effects of the concentrator factor on the performance of the system are discussed. - Abstract: A model of the solar thermophotovoltaic system (STPVS) consisting of an optical concentrator, a thermal absorber, an emitter, and a photovoltaic (PV) cell is proposed, where the far-field thermal emission between the emitter and the PV cell, the radiation losses from the absorber and emitter to the environment, the reflected loss from the absorber, and the finite-rate heat exchange between the PV cell and the environment are taken into account. Analytical expressions for the power output of and overall efficiency of the STPVS are derived. By solving thermal equilibrium equations, the operating temperatures of the emitter and PV cell are determined and the maximum efficiency of the system is calculated numerically for given values of the output voltage of the PV cell and the ratio of the front surface area of the absorber to that of the emitter. For different bandgaps, the maximum efficiencies of the system are calculated and the corresponding optimum values of several operating parameters are obtained. The effects of the concentrator factor on the optimum performance of the system are also discussed.

13 CFR 107.840 - Maximum term of Financing.

Science.gov (United States)

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Maximum term of Financing. 107.840... COMPANIES Financing of Small Businesses by Licensees Structuring Licensee's Financing of An Eligible Small Business: Terms and Conditions of Financing § 107.840 Maximum term of Financing. The maximum term of any...

Adoption of the American Academy of Pediatrics’ neonatal hyperbilirubinemia guidelines and its effect on blood exchange transfusion rate in a tertiary care center in Amman, Jordan

Directory of Open Access Journals (Sweden)

Al-Lawama M

2018-04-01

Full Text Available Manar Al-Lawama, Eman Al-Rimawi, Rawan Al-Shibi, Eman Badran Department of Pediatrics, The University of Jordan, School of Medicine, Amman, Jordan Introduction: Severe neonatal hyperbilirubinemia can cause mortality and serious morbidities. When phototherapy fails, neonates with severe hyperbilirubinemia should undergo double volume blood exchange transfusion (BET. As this procedure carries a significant risk of mortality and morbidity, adopting guidelines for the treatment of neonatal hyperbilirubinemia is critical to avoid hyperbilirubinemia toxicity and also the complication of an unindicated procedure. Methods: This study investigated the causes, complications, and trend of BET rate in our unit over a 13-year period. The medical charts and laboratory databases of all infants who underwent BET in Jordan University Hospital between 2003 and 2015 were retrospectively reviewed. Results: The rate of exchange cases decreased significantly after adopting the guidelines of American Academy of Pediatrics (P<0.0001. Most neonates were term newborns (69%. Average birth weight was 2,800 g. The most common causes of exchange transfusion were non-hemolytic conditions. Late prematurity alone accounted for 20% of the cases. Thrombocytopenia was the most commonly encountered complication (33%. Chronic neurological complications were seen in 12% of those who were followed for >12 months of age. Conclusions: This study showed a clear decline in the rate of BET after implementing the guidelines of American Academy of Pediatrics. In addition to improving the strategies for the identification and follow-up of at-risk newborns, we should intensify our efforts to prevent the progression of neonatal hyperbilirubinemia to the exchange level by enhancing parents’ ­awareness of this potentially harmful neonatal condition. Keywords: neonate, exchange transfusion, hyperbilirubinemia, guidelines, Jordan

Estimation of the Maximum Theoretical Productivity of Fed-Batch Bioreactors

Energy Technology Data Exchange (ETDEWEB)

Bomble, Yannick J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); St. John, Peter C [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Crowley, Michael F [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-10-18

A key step towards the development of an integrated biorefinery is the screening of economically viable processes, which depends sharply on the yields and productivities that can be achieved by an engineered microorganism. In this study, we extend an earlier method which used dynamic optimization to find the maximum theoretical productivity of batch cultures to explicitly include fed-batch bioreactors. In addition to optimizing the intracellular distribution of metabolites between cell growth and product formation, we calculate the optimal control trajectory of feed rate versus time. We further analyze how sensitive the productivity is to substrate uptake and growth parameters.

20 CFR 226.52 - Total annuity subject to maximum.

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Total annuity subject to maximum. 226.52... COMPUTING EMPLOYEE, SPOUSE, AND DIVORCED SPOUSE ANNUITIES Railroad Retirement Family Maximum § 226.52 Total annuity subject to maximum. The total annuity amount which is compared to the maximum monthly amount to...

Application of the maximum entropy production principle to electrical systems

International Nuclear Information System (INIS)

Christen, Thomas

2006-01-01

For a simple class of electrical systems, the principle of the maximum entropy production rate (MaxEP) is discussed. First, we compare the MaxEP principle and the principle of the minimum entropy production rate and illustrate the superiority of the MaxEP principle for the example of two parallel constant resistors. Secondly, we show that the Steenbeck principle for the electric arc as well as the ohmic contact behaviour of space-charge limited conductors follow from the MaxEP principle. In line with work by Dewar, the investigations seem to suggest that the MaxEP principle can also be applied to systems far from equilibrium, provided appropriate information is available that enters the constraints of the optimization problem. Finally, we apply the MaxEP principle to a mesoscopic system and show that the universal conductance quantum, e 2 /h, of a one-dimensional ballistic conductor can be estimated

Maximum And Minimum Temperature Trends In Mexico For The Last 31 Years

Science.gov (United States)

Romero-Centeno, R.; Zavala-Hidalgo, J.; Allende Arandia, M. E.; Carrasco-Mijarez, N.; Calderon-Bustamante, O.

2013-05-01

Based on high-resolution (1') daily maps of the maximum and minimum temperatures in Mexico, an analysis of the last 31-year trends is performed. The maps were generated using all the available information from more than 5,000 stations of the Mexican Weather Service (Servicio Meteorológico Nacional, SMN) for the period 1979-2009, along with data from the North American Regional Reanalysis (NARR). The data processing procedure includes a quality control step, in order to eliminate erroneous daily data, and make use of a high-resolution digital elevation model (from GEBCO), the relationship between air temperature and elevation by means of the average environmental lapse rate, and interpolation algorithms (linear and inverse-distance weighting). Based on the monthly gridded maps for the mentioned period, the maximum and minimum temperature trends calculated by least-squares linear regression and their statistical significance are obtained and discussed.

Global view of F-region electron density and temperature at solar maximum

International Nuclear Information System (INIS)

Brace, L.H.; Theis, R.F.; Hoegy, W.R.

1982-01-01

Dynamics Explorer-2 is permitting the first measurements of the global structure of the F-regions at very high levels of solar activity (S>200). Selected full orbits of Langmuir probe measurements of electron temperature, T/sub e/, and density, N/sub e/, are shown to illustrate this global structure and some of the ionospheric features that are the topic of other papers in this issue. The ionospheric thermal structure is of particular interest because T/sub e/ is a sensitive indicator of the coupling of magnetospheric energy into the upper atmosphere. A comparison of these heating effects with those observed at solar minimum shows that the magnetospheric sources are more important at solar maximum, as might have been expected. Heating at the cusp, the auroral oval and the plasma-pause is generally both greater and more variable. Electron cooling rate calculations employing low latitude measurements indicate that solar extreme ultraviolet heating of the F region at solar maximum is enhanced by a factor that is greater than the increase in solar flux. Some of this enhanced electron heating arises from the increase in electron heating efficiency at the higher N/sub e/ of solar maximum, but this appears insufficient to completely resolve the discrepancy

Maximum likely scale estimation

DEFF Research Database (Denmark)

Loog, Marco; Pedersen, Kim Steenstrup; Markussen, Bo

2005-01-01

A maximum likelihood local scale estimation principle is presented. An actual implementation of the estimation principle uses second order moments of multiple measurements at a fixed location in the image. These measurements consist of Gaussian derivatives possibly taken at several scales and/or ...

A discussion about maximum uranium concentration in digestion solution of U3O8 type uranium ore concentrate

International Nuclear Information System (INIS)

Xia Dechang; Liu Chao

2012-01-01

On the basis of discussing the influence of single factor on maximum uranium concentration in digestion solution,the influence degree of some factors such as U content, H 2 O content, mass ratio of P and U was compared and analyzed. The results indicate that the relationship between U content and maximum uranium concentration in digestion solution was direct ratio, while the U content increases by 1%, the maximum uranium concentration in digestion solution increases by 4.8%-5.7%. The relationship between H 2 O content and maximum uranium concentration in digestion solution was inverse ratio, the maximum uranium concentration in digestion solution decreases by 46.1-55.2 g/L while H 2 O content increases by 1%. The relationship between mass ratio of P and U and maximum uranium concentration in digestion solution was inverse ratio, the maximum uranium concentration in digestion solution decreases by 116.0-181.0 g/L while the mass ratio of P and U increase 0.1%. When U content equals 62.5% and the influence of mass ratio of P and U is no considered, the maximum uranium concentration in digestion solution equals 1 578 g/L; while mass ratio of P and U equals 0.35%, the maximum uranium concentration decreases to 716 g/L, the decreased rate is 54.6%, so the mass ratio of P and U in U 3 O 8 type uranium ore concentrate is the main controlling factor. (authors)

Temperature effects on lithium-nitrogen reaction rates

International Nuclear Information System (INIS)

Ijams, W.J.; Kazimi, M.S.

1985-08-01

A series of experiments have been run with the aim of measuring the reaction rate of lithium and nitrogen over a wide spectrum of lithium pool temperatures. In these experiments, pure nitrogen was blown at a controlled flow rate over a preheated lithium pool. The pool had a surface area of approximately 4 cm 2 and a total volume of approximately 6 cm 3 . The system pressure varied from 0 to 4 psig. The reaction rate was very small - approximately 0.002 to 0.003 g Li min cm 2 for lithium temperatures below 500 0 C. Above 500 0 C the reaction rate began to increase sharply, and reached a maximum of approximately 0.80 g Li min cm 2 above 700 0 C. It dropped off beyond 1000 0 C and seemed to approach zero at 1150 0 C. The maximum reaction rate observed in these forced convection experiments was higher by 60% than those previously observed in experiments where the nitrogen flowed to the reaction site by means of natural convection. During a reaction, a hard nitride layer built up on the surface of the lithium pool - its effect on the reaction rate was observed. The effect of the nitrogen flow rate on the reaction rate was also observed

The Hengill geothermal area, Iceland: Variation of temperature gradients deduced from the maximum depth of seismogenesis

Science.gov (United States)

Foulger, G. R.

1995-04-01

Given a uniform lithology and strain rate and a full seismic data set, the maximum depth of earthquakes may be viewed to a first order as an isotherm. These conditions are approached at the Hengill geothermal area S. Iceland, a dominantly basaltic area. The likely strain rate calculated from thermal and tectonic considerations is 10 -15 s -1, and temperature measurements from four drill sites within the area indicate average, near-surface geothermal gradients of up to 150 °C km -1 throughout the upper 2 km. The temperature at which seismic failure ceases for the strain rates likely at the Hengill geothermal area is determined by analogy with oceanic crust, and is about 650 ± 50 °C. The topographies of the top and bottom of the seismogenic layer were mapped using 617 earthquakes located highly accurately by performing a simultaneous inversion for three-dimensional structure and hypocentral parameters. The thickness of the seismogenic layer is roughly constant and about 3 km. A shallow, aseismic, low-velocity volume within the spreading plate boundary that crosses the area occurs above the top of the seismogenic layer and is interpreted as an isolated body of partial melt. The base of the seismogenic layer has a maximum depth of about 6.5 km beneath the spreading axis and deepens to about 7 km beneath a transform zone in the south of the area. Beneath the high-temperature part of the geothermal area, the maximum depth of earthquakes may be as shallow as 4 km. The geothermal gradient below drilling depths in various parts of the area ranges from 84 ± 9 °Ckm -1 within the low-temperature geothermal area of the transform zone to 138 ± 15 °Ckm -1 below the centre of the high-temperature geothermal area. Shallow maximum depths of earthquakes and therefore high average geothermal gradients tend to correlate with the intensity of the geothermal area and not with the location of the currently active spreading axis.

Maximum gravitational redshift of white dwarfs

International Nuclear Information System (INIS)

Shapiro, S.L.; Teukolsky, S.A.

1976-01-01

The stability of uniformly rotating, cold white dwarfs is examined in the framework of the Parametrized Post-Newtonian (PPN) formalism of Will and Nordtvedt. The maximum central density and gravitational redshift of a white dwarf are determined as functions of five of the nine PPN parameters (γ, β, zeta 2 , zeta 3 , and zeta 4 ), the total angular momentum J, and the composition of the star. General relativity predicts that the maximum redshifts is 571 km s -1 for nonrotating carbon and helium dwarfs, but is lower for stars composed of heavier nuclei. Uniform rotation can increase the maximum redshift to 647 km s -1 for carbon stars (the neutronization limit) and to 893 km s -1 for helium stars (the uniform rotation limit). The redshift distribution of a larger sample of white dwarfs may help determine the composition of their cores

Revealing the Maximum Strength in Nanotwinned Copper

DEFF Research Database (Denmark)

Lu, L.; Chen, X.; Huang, Xiaoxu

2009-01-01

boundary–related processes. We investigated the maximum strength of nanotwinned copper samples with different twin thicknesses. We found that the strength increases with decreasing twin thickness, reaching a maximum at 15 nanometers, followed by a softening at smaller values that is accompanied by enhanced...

49 CFR 195.406 - Maximum operating pressure.

Science.gov (United States)

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false Maximum operating pressure. 195.406 Section 195.406 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS... HAZARDOUS LIQUIDS BY PIPELINE Operation and Maintenance § 195.406 Maximum operating pressure. (a) Except for...

Improving the maximum transmission distance of continuous-variable quantum key distribution with noisy coherent states using a noiseless amplifier

International Nuclear Information System (INIS)

Wang, Tianyi; Yu, Song; Zhang, Yi-Chen; Gu, Wanyi; Guo, Hong

2014-01-01

By employing a nondeterministic noiseless linear amplifier, we propose to increase the maximum transmission distance of continuous-variable quantum key distribution with noisy coherent states. With the covariance matrix transformation, the expression of secret key rate under reverse reconciliation is derived against collective entangling cloner attacks. We show that the noiseless linear amplifier can compensate the detrimental effect of the preparation noise with an enhancement of the maximum transmission distance and the noise resistance. - Highlights: • Noiseless amplifier is applied in noisy coherent state quantum key distribution. • Negative effect of preparation noise is compensated by noiseless amplification. • Maximum transmission distance and noise resistance are both enhanced

Increasing preferred step rate during running reduces plantar pressures.

Science.gov (United States)

Gerrard, James M; Bonanno, Daniel R

2018-01-01

Increasing preferred step rate during running is a commonly used strategy in the management of running-related injuries. This study investigated the effect of different step rates on plantar pressures during running. Thirty-two healthy runners ran at a comfortable speed on a treadmill at five step rates (preferred, ±5%, and ±10%). For each step rate, plantar pressure data were collected using the pedar-X in-shoe system. Compared to running with a preferred step rate, a 10% increase in step rate significantly reduced peak pressure (144.5±46.5 vs 129.3±51 kPa; P=.033) and maximum force (382.3±157.6 vs 334.0±159.8 N; P=.021) at the rearfoot, and reduced maximum force (426.4±130.4 vs 400.0±116.6 N; P=.001) at the midfoot. In contrast, a 10% decrease in step rate significantly increased peak pressure (144.5±46.5 vs 161.5±49.3 kPa; P=.011) and maximum force (382.3±157.6 vs 425.4±155.3 N; P=.032) at the rearfoot. Changing step rate by 5% provided no effect on plantar pressures, and no differences in plantar pressures were observed at the medial forefoot, lateral forefoot or hallux between the step rates. This study's findings indicate that increasing preferred step rate by 10% during running will reduce plantar pressures at the rearfoot and midfoot, while decreasing step rate by 10% will increase plantar pressures at the rearfoot. However, changing preferred step rate by 5% will provide no effect on plantar pressures, and forefoot pressures are unaffected by changes in step rate. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Maximum spectral demands in the near-fault region

Science.gov (United States)

Huang, Yin-Nan; Whittaker, Andrew S.; Luco, Nicolas

2008-01-01

The Next Generation Attenuation (NGA) relationships for shallow crustal earthquakes in the western United States predict a rotated geometric mean of horizontal spectral demand, termed GMRotI50, and not maximum spectral demand. Differences between strike-normal, strike-parallel, geometric-mean, and maximum spectral demands in the near-fault region are investigated using 147 pairs of records selected from the NGA strong motion database. The selected records are for earthquakes with moment magnitude greater than 6.5 and for closest site-to-fault distance less than 15 km. Ratios of maximum spectral demand to NGA-predicted GMRotI50 for each pair of ground motions are presented. The ratio shows a clear dependence on period and the Somerville directivity parameters. Maximum demands can substantially exceed NGA-predicted GMRotI50 demands in the near-fault region, which has significant implications for seismic design, seismic performance assessment, and the next-generation seismic design maps. Strike-normal spectral demands are a significantly unconservative surrogate for maximum spectral demands for closest distance greater than 3 to 5 km. Scale factors that transform NGA-predicted GMRotI50 to a maximum spectral demand in the near-fault region are proposed.

A rotation-symmetric, position-sensitive annular detector for maximum counting rates

International Nuclear Information System (INIS)

Igel, S.

1993-12-01

The Germanium Wall is a semiconductor detector system containing up to four annular position sensitive ΔE-detectors from high purity germanium (HPGe) planned to complement the BIG KARL spectrometer in COSY experiments. The first diode of the system, the Quirl-detector, has a two dimensional position sensitive structure defined by 200 Archimedes' spirals on each side with opposite orientation. In this way about 40000 pixels are defined. Since each spiral element detects almost the same number of events in an experiment the whole system can be optimized for maximal counting rates. This paper describes a test setup for a first prototype of the Quirl-detector and the results of test measurements with an α-source. The detector current and the electrical separation of the spiral elements were measured. The splitting of signals due to the spread of charge carriers produced by an incident ionizing particle on several adjacent elements was investigated in detail and found to be twice as high as expected from calculations. Its influence on energy and position resolution is discussed. Electronic crosstalk via signal wires and the influence of noise from the magnetic spectrometer has been tested under experimental conditions. Additionally, vacuum feedthroughs based on printed Kapton foils pressed between Viton seals were fabricated and tested successfully concerning their vacuum and thermal properties. (orig.)

Maximum allowable load on wheeled mobile manipulators

International Nuclear Information System (INIS)

Habibnejad Korayem, M.; Ghariblu, H.

2003-01-01

This paper develops a computational technique for finding the maximum allowable load of mobile manipulator during a given trajectory. The maximum allowable loads which can be achieved by a mobile manipulator during a given trajectory are limited by the number of factors; probably the dynamic properties of mobile base and mounted manipulator, their actuator limitations and additional constraints applied to resolving the redundancy are the most important factors. To resolve extra D.O.F introduced by the base mobility, additional constraint functions are proposed directly in the task space of mobile manipulator. Finally, in two numerical examples involving a two-link planar manipulator mounted on a differentially driven mobile base, application of the method to determining maximum allowable load is verified. The simulation results demonstrates the maximum allowable load on a desired trajectory has not a unique value and directly depends on the additional constraint functions which applies to resolve the motion redundancy

Robust Maximum Association Estimators

NARCIS (Netherlands)

A. Alfons (Andreas); C. Croux (Christophe); P. Filzmoser (Peter)

2017-01-01

textabstractThe maximum association between two multivariate variables X and Y is defined as the maximal value that a bivariate association measure between one-dimensional projections αX and αY can attain. Taking the Pearson correlation as projection index results in the first canonical correlation

Selection of the Maximum Spatial Cluster Size of the Spatial Scan Statistic by Using the Maximum Clustering Set-Proportion Statistic.

Science.gov (United States)

Ma, Yue; Yin, Fei; Zhang, Tao; Zhou, Xiaohua Andrew; Li, Xiaosong

2016-01-01

Spatial scan statistics are widely used in various fields. The performance of these statistics is influenced by parameters, such as maximum spatial cluster size, and can be improved by parameter selection using performance measures. Current performance measures are based on the presence of clusters and are thus inapplicable to data sets without known clusters. In this work, we propose a novel overall performance measure called maximum clustering set-proportion (MCS-P), which is based on the likelihood of the union of detected clusters and the applied dataset. MCS-P was compared with existing performance measures in a simulation study to select the maximum spatial cluster size. Results of other performance measures, such as sensitivity and misclassification, suggest that the spatial scan statistic achieves accurate results in most scenarios with the maximum spatial cluster sizes selected using MCS-P. Given that previously known clusters are not required in the proposed strategy, selection of the optimal maximum cluster size with MCS-P can improve the performance of the scan statistic in applications without identified clusters.

Maximum-Likelihood Detection Of Noncoherent CPM

Science.gov (United States)

Divsalar, Dariush; Simon, Marvin K.

1993-01-01

Simplified detectors proposed for use in maximum-likelihood-sequence detection of symbols in alphabet of size M transmitted by uncoded, full-response continuous phase modulation over radio channel with additive white Gaussian noise. Structures of receivers derived from particular interpretation of maximum-likelihood metrics. Receivers include front ends, structures of which depends only on M, analogous to those in receivers of coherent CPM. Parts of receivers following front ends have structures, complexity of which would depend on N.

Maximum solid concentrations of coal water slurries predicted by neural network models

Energy Technology Data Exchange (ETDEWEB)

Cheng, Jun; Li, Yanchang; Zhou, Junhu; Liu, Jianzhong; Cen, Kefa

2010-12-15

The nonlinear back-propagation (BP) neural network models were developed to predict the maximum solid concentration of coal water slurry (CWS) which is a substitute for oil fuel, based on physicochemical properties of 37 typical Chinese coals. The Levenberg-Marquardt algorithm was used to train five BP neural network models with different input factors. The data pretreatment method, learning rate and hidden neuron number were optimized by training models. It is found that the Hardgrove grindability index (HGI), moisture and coalification degree of parent coal are 3 indispensable factors for the prediction of CWS maximum solid concentration. Each BP neural network model gives a more accurate prediction result than the traditional polynomial regression equation. The BP neural network model with 3 input factors of HGI, moisture and oxygen/carbon ratio gives the smallest mean absolute error of 0.40%, which is much lower than that of 1.15% given by the traditional polynomial regression equation. (author)

Maximum total organic carbon limits at different DWPF melter feed maters (U)

International Nuclear Information System (INIS)

Choi, A.S.

1996-01-01

The document presents information on the maximum total organic carbon (TOC) limits that are allowable in the DWPF melter feed without forming a potentially flammable vapor in the off-gas system were determined at feed rates varying from 0.7 to 1.5 GPM. At the maximum TOC levels predicted, the peak concentration of combustible gases in the quenched off-gas will not exceed 60 percent of the lower flammable limit during a 3X off-gas surge, provided that the indicated melter vapor space temperature and the total air supply to the melter are maintained. All the necessary calculations for this study were made using the 4-stage cold cap model and the melter off-gas dynamics model. A high-degree of conservatism was included in the calculational bases and assumptions. As a result, the proposed correlations are believed to by conservative enough to be used for the melter off-gas flammability control purposes

Maximum mass ratio of am CVn-type binary systems and maximum white dwarf mass in ultra-compact x-ray binaries (addendum - Serb. Astron. J. No. 183 (2011, 63

Directory of Open Access Journals (Sweden)

Arbutina B.

2012-01-01

Full Text Available We recalculated the maximum white dwarf mass in ultra-compact X-ray binaries obtained in an earlier paper (Arbutina 2011, by taking the effects of super-Eddington accretion rate on the stability of mass transfer into account. It is found that, although the value formally remains the same (under the assumed approximations, for white dwarf masses M2 >~0.1MCh mass ratios are extremely low, implying that the result for Mmax is likely to have little if any practical relevance.

Maximum Entropy Fundamentals

Directory of Open Access Journals (Sweden)

F. Topsøe

2001-09-01

Full Text Available Abstract: In its modern formulation, the Maximum Entropy Principle was promoted by E.T. Jaynes, starting in the mid-fifties. The principle dictates that one should look for a distribution, consistent with available information, which maximizes the entropy. However, this principle focuses only on distributions and it appears advantageous to bring information theoretical thinking more prominently into play by also focusing on the "observer" and on coding. This view was brought forward by the second named author in the late seventies and is the view we will follow-up on here. It leads to the consideration of a certain game, the Code Length Game and, via standard game theoretical thinking, to a principle of Game Theoretical Equilibrium. This principle is more basic than the Maximum Entropy Principle in the sense that the search for one type of optimal strategies in the Code Length Game translates directly into the search for distributions with maximum entropy. In the present paper we offer a self-contained and comprehensive treatment of fundamentals of both principles mentioned, based on a study of the Code Length Game. Though new concepts and results are presented, the reading should be instructional and accessible to a rather wide audience, at least if certain mathematical details are left aside at a rst reading. The most frequently studied instance of entropy maximization pertains to the Mean Energy Model which involves a moment constraint related to a given function, here taken to represent "energy". This type of application is very well known from the literature with hundreds of applications pertaining to several different elds and will also here serve as important illustration of the theory. But our approach reaches further, especially regarding the study of continuity properties of the entropy function, and this leads to new results which allow a discussion of models with so-called entropy loss. These results have tempted us to speculate over

Theory and application of maximum magnetic energy in toroidal plasmas

International Nuclear Information System (INIS)

Chu, T.K.

1992-02-01

The magnetic energy in an inductively driven steady-state toroidal plasma is a maximum for a given rate of dissipation of energy (Poynting flux). A purely resistive steady state of the piecewise force-free configuration, however, cannot exist, as the periodic removal of the excess poloidal flux and pressure, due to heating, ruptures the static equilibrium of the partitioning rational surfaces intermittently. The rupture necessitates a plasma with a negative q'/q (as in reverse field pinches and spheromaks) to have the same α in all its force-free regions and with a positive q'/q (as in tokamaks) to have centrally peaked α's

Variable Step Size Maximum Correntropy Criteria Based Adaptive Filtering Algorithm

Directory of Open Access Journals (Sweden)

S. Radhika

2016-04-01

Full Text Available Maximum correntropy criterion (MCC based adaptive filters are found to be robust against impulsive interference. This paper proposes a novel MCC based adaptive filter with variable step size in order to obtain improved performance in terms of both convergence rate and steady state error with robustness against impulsive interference. The optimal variable step size is obtained by minimizing the Mean Square Deviation (MSD error from one iteration to the other. Simulation results in the context of a highly impulsive system identification scenario show that the proposed algorithm has faster convergence and lesser steady state error than the conventional MCC based adaptive filters.

Surface of Maximums of AR(2 Process Spectral Densities and its Application in Time Series Statistics

Directory of Open Access Journals (Sweden)

Alexander V. Ivanov

2017-09-01

Conclusions. The obtained formula of surface of maximums of noise spectral densities gives an opportunity to realize for which values of AR(2 process characteristic polynomial coefficients it is possible to look for greater rate of convergence to zero of the probabilities of large deviations of the considered estimates.

Determination of the maximum-depth to potential field sources by a maximum structural index method

Science.gov (United States)

Fedi, M.; Florio, G.

2013-01-01

A simple and fast determination of the limiting depth to the sources may represent a significant help to the data interpretation. To this end we explore the possibility of determining those source parameters shared by all the classes of models fitting the data. One approach is to determine the maximum depth-to-source compatible with the measured data, by using for example the well-known Bott-Smith rules. These rules involve only the knowledge of the field and its horizontal gradient maxima, and are independent from the density contrast. Thanks to the direct relationship between structural index and depth to sources we work out a simple and fast strategy to obtain the maximum depth by using the semi-automated methods, such as Euler deconvolution or depth-from-extreme-points method (DEXP). The proposed method consists in estimating the maximum depth as the one obtained for the highest allowable value of the structural index (Nmax). Nmax may be easily determined, since it depends only on the dimensionality of the problem (2D/3D) and on the nature of the analyzed field (e.g., gravity field or magnetic field). We tested our approach on synthetic models against the results obtained by the classical Bott-Smith formulas and the results are in fact very similar, confirming the validity of this method. However, while Bott-Smith formulas are restricted to the gravity field only, our method is applicable also to the magnetic field and to any derivative of the gravity and magnetic field. Our method yields a useful criterion to assess the source model based on the (∂f/∂x)max/fmax ratio. The usefulness of the method in real cases is demonstrated for a salt wall in the Mississippi basin, where the estimation of the maximum depth agrees with the seismic information.

Studying radon exhalation rates variability from phosphogypsum piles in the SW of Spain

Energy Technology Data Exchange (ETDEWEB)

López-Coto, I., E-mail: israel.lopez@dfa.uhu.es [Dpto. Física Aplicada, Facultad CC. Experimentales, University of Huelva, Campus de El Carmen s/n, 21007 Huelva (Spain); Mas, J.L. [Dpto. Física Aplicada I. Escuela Politécnica Superior, University of Sevilla, C/Virgen de Africa 7, 41012 Sevilla (Spain); Vargas, A. [Universitat Politècnica de Catalunya, Instituto de Técnicas Energéticas, Campus Sud Edificio ETSEIB, Planta 0, Pabellón C, Av. Diagonal 647, 08028 Barcelona (Spain); Bolívar, J.P. [Dpto. Física Aplicada, Facultad CC. Experimentales, University of Huelva, Campus de El Carmen s/n, 21007 Huelva (Spain)

2014-09-15

Highlights: • Variability of radon exhalation rates from PG piles has been studied using numerical simulation supported by experimental data. • Most relevant parameters controlling the exhalation rate are radon potential and moisture saturation. • Piling up the waste increasing the height instead of the surface allows the reduction of the exhalation rate. • A proposed cover here is expected to allow exhalation rates reductions up to 95%. - Abstract: Nearly 1.0 × 10{sup 8} tonnes of phosphogypsum were accumulated during last 50 years on a 1200 ha disposal site near Huelva town (SW of Spain). Previous measurements of exhalation rates offered very variable values, in such a way that a worst case scenario could not be established. Here, new experimental data coupled to numerical simulations show that increasing the moisture contents or the temperature reduces the exhalation rate whilst increasing the radon potential or porosity has the contrary effect. Once the relative effects are compared, it can be drawn that the most relevant parameters controlling the exhalation rate are radon potential (product of emanation factor by {sup 226}Ra concentration) and moisture saturation of PG. From wastes management point of view, it can be concluded that piling up the waste increasing the height instead of the surface allows the reduction of the exhalation rate. Furthermore, a proposed cover here is expected to allow exhalation rates reductions up to 95%. We established that the worst case scenario corresponds to a situation of extremely dry winter. Under these conditions, the radon exhalation rate (0.508 Bq m{sup −2} s{sup −1}) would be below though close to the upper limit established by U.S.E.P.A. for inactive phopsphogypsum piles (0.722 Bq m{sup −2} s{sup −1})

LIBOR troubles: Anomalous movements detection based on maximum entropy

Science.gov (United States)

Bariviera, Aurelio F.; Martín, María T.; Plastino, Angelo; Vampa, Victoria

2016-05-01

According to the definition of the London Interbank Offered Rate (LIBOR), contributing banks should give fair estimates of their own borrowing costs in the interbank market. Between 2007 and 2009, several banks made inappropriate submissions of LIBOR, sometimes motivated by profit-seeking from their trading positions. In 2012, several newspapers' articles began to cast doubt on LIBOR integrity, leading surveillance authorities to conduct investigations on banks' behavior. Such procedures resulted in severe fines imposed to involved banks, who recognized their financial inappropriate conduct. In this paper, we uncover such unfair behavior by using a forecasting method based on the Maximum Entropy principle. Our results are robust against changes in parameter settings and could be of great help for market surveillance.

Optimization between heating load and entropy-production rate for endoreversible absorption heat-transformers

International Nuclear Information System (INIS)

Sun Fengrui; Qin Xiaoyong; Chen Lingen; Wu Chih

2005-01-01

For an endoreversible four-heat-reservoir absorption heat-transformer cycle, for which a linear (Newtonian) heat-transfer law applies, an ecological optimization criterion is proposed for the best mode of operation of the cycle. This involves maximizing a function representing the compromise between the heating load and the entropy-production rate. The optimal relation between the ecological criterion and the COP (coefficient of performance), the maximum ecological criterion and the corresponding COP, heating load and entropy production rate, as well as the ecological criterion and entropy-production rate at the maximum heating load are derived using finite-time thermodynamics. Moreover, compared with the heating-load criterion, the effects of the cycle parameters on the ecological performance are studied by numerical examples. These show that achieving the maximum ecological criterion makes the entropy-production rate decrease by 77.0% and the COP increase by 55.4% with only 27.3% heating-load losses compared with the maximum heating-load objective. The results reflect that the ecological criterion has long-term significance for optimal design of absorption heat-transformers

40 CFR 141.13 - Maximum contaminant levels for turbidity.

Science.gov (United States)

2010-07-01

... turbidity. 141.13 Section 141.13 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER... Maximum contaminant levels for turbidity. The maximum contaminant levels for turbidity are applicable to... part. The maximum contaminant levels for turbidity in drinking water, measured at a representative...

40 CFR 141.62 - Maximum contaminant levels for inorganic contaminants.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Maximum contaminant levels for inorganic contaminants. 141.62 Section 141.62 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Water Regulations: Maximum Contaminant Levels and Maximum Residual Disinfectant Levels § 141.62 Maximum...

Assessment of maximum available work of a hydrogen fueled compression ignition engine using exergy analysis

International Nuclear Information System (INIS)

Chintala, Venkateswarlu; Subramanian, K.A.

2014-01-01

This work is aimed at study of maximum available work and irreversibility (mixing, combustion, unburned, and friction) of a dual-fuel diesel engine (H 2 (hydrogen)–diesel) using exergy analysis. The maximum available work increased with H 2 addition due to reduction in irreversibility of combustion because of less entropy generation. The irreversibility of unburned fuel with the H 2 fuel also decreased due to the engine combustion with high temperature whereas there is no effect of H 2 on mixing and friction irreversibility. The maximum available work of the diesel engine at rated load increased from 29% with conventional base mode (without H 2 ) to 31.7% with dual-fuel mode (18% H 2 energy share) whereas total irreversibility of the engine decreased drastically from 41.2% to 39.3%. The energy efficiency of the engine with H 2 increased about 10% with 36% reduction in CO 2 emission. The developed methodology could also be applicable to find the effect and scope of different technologies including exhaust gas recirculation and turbo charging on maximum available work and energy efficiency of diesel engines. - Highlights: • Energy efficiency of diesel engine increases with hydrogen under dual-fuel mode. • Maximum available work of the engine increases significantly with hydrogen. • Combustion and unburned fuel irreversibility decrease with hydrogen. • No significant effect of hydrogen on mixing and friction irreversibility. • Reduction in CO 2 emission along with HC, CO and smoke emissions

Weak scale from the maximum entropy principle

Science.gov (United States)

Hamada, Yuta; Kawai, Hikaru; Kawana, Kiyoharu

2015-03-01

The theory of the multiverse and wormholes suggests that the parameters of the Standard Model (SM) are fixed in such a way that the radiation of the S3 universe at the final stage S_rad becomes maximum, which we call the maximum entropy principle. Although it is difficult to confirm this principle generally, for a few parameters of the SM, we can check whether S_rad actually becomes maximum at the observed values. In this paper, we regard S_rad at the final stage as a function of the weak scale (the Higgs expectation value) vh, and show that it becomes maximum around vh = {{O}} (300 GeV) when the dimensionless couplings in the SM, i.e., the Higgs self-coupling, the gauge couplings, and the Yukawa couplings are fixed. Roughly speaking, we find that the weak scale is given by vh ˜ T_{BBN}2 / (M_{pl}ye5), where ye is the Yukawa coupling of electron, T_BBN is the temperature at which the Big Bang nucleosynthesis starts, and M_pl is the Planck mass.

Accurate modeling and maximum power point detection of ...

African Journals Online (AJOL)

Accurate modeling and maximum power point detection of photovoltaic ... Determination of MPP enables the PV system to deliver maximum available power. ..... adaptive artificial neural network: Proposition for a new sizing procedure.

40 CFR 141.61 - Maximum contaminant levels for organic contaminants.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Maximum contaminant levels for organic contaminants. 141.61 Section 141.61 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER... Regulations: Maximum Contaminant Levels and Maximum Residual Disinfectant Levels § 141.61 Maximum contaminant...

Maximum Power Training and Plyometrics for Cross-Country Running.

Science.gov (United States)

Ebben, William P.

2001-01-01

Provides a rationale for maximum power training and plyometrics as conditioning strategies for cross-country runners, examining: an evaluation of training methods (strength training and maximum power training and plyometrics); biomechanic and velocity specificity (role in preventing injury); and practical application of maximum power training and…

Extraction and purification of {sup 227}Ac and development of solid {sup 219}Rn source

Energy Technology Data Exchange (ETDEWEB)

Tang, Quan; Qiu, Shoukang; Xiao, Detao; Zhou, Yaohui; An, Xiaogang [University of South China, Hengyang (China). Radon Key Laboratory of Hunan Province/School of Nuclear Science and Technology

2014-04-01

The method of {sup 227}Ac extraction and purification from high-grade uranium ore and the test results of solid {sup 219}Rn source made from {sup 227}Ac are reported in this paper. With five years of follow-up monitoring, radiochemical purity of {sup 227}Ac and the emanation power of solid {sup 219}Rn source has been checked by emanation method and γ-spectrometry, the results showed that {sup 228}Th, {sup 231}Pa and {sup 226}Ra have been effectively removed and the emanation power of {sup 219}Rn source is about 80%. The long-term test results also showed that the {sup 219}Rn emanation rate remains stable in a wide air humidity range (40% ∝ 90%). Though the {sup 219}Rn source has not been accurately calibrated yet, it has been applied in the research for delay coincidence measurement of {sup 223}Ra. (orig.)

Outpacing the Anthropocene: New Constraints for the Rate of Carbon Release at the Paleocene-Eocene Thermal Maximum

Science.gov (United States)

Wright, J. D.; Schaller, M. F.

2012-12-01

The Paleocene/Eocene Thermal Maximum (PETM) Carbon Isotope Excursion (CIE) is linked to benthic foraminiferal extinction and excursion taxa in planktonic foraminifera and calcareous nannofossils. Previous studies have used integrated bio-magneto-stratigraphies, cycle counting, and extraterrestrial 3He accumulation rates to produce a range of estimates for the duration of the initial onset of the PETM CIE between 750 years to 30 kyr. Durations for the total release time (onset to initiation of recovery) range from 45 to 95 kyr. Uncertainty in the timing of the onset of the PETM CIE prevents the identification of a causal mechanism, and hence understanding the biological responses. Recent work on the Paleocene/Eocene Marlboro Clay has unveiled the presence of regular couplets (~2 cm) expressed in multiple cores and exposures throughout the Atlantic Coastal Plain. Specifically, the Millville and newly recovered Wilson Lake B cores contain 750 and 660 layers through the CIE, respectively. These couplets have corresponding oxygen stable isotope cycles, arguing for a climatic origin. Orbital and millennial periodicities are far too long to explain the ~750 layers identified in the Millville core. Seasonal insolation is the only regular climate cycle that can plausibly account for the observed δ18O amplitudes (~1‰, with some cycles up to 2‰) and layer counts. Seasonal freshwater input can also augment the cyclic oscillations in δ18O, but the majority of the variability is most plausibly ascribed to temperature. Wilson Lake B and Millville have total δ13C excursions of -5 and -4.5‰ respectively, as well as highly expanded sections of the PETM CIE. In the Millville core, high-resolution, bulk stable isotope records show a 3.5‰ δ13C decrease over 12 layers across the PETM CIE onset. Concomitant with this δ13C decrease is a sharp drop in CaCO3. Decreases in both proxies require a large, sudden release of isotopically light carbon. The couplet chronology indicates

The last glacial maximum

Science.gov (United States)

Clark, P.U.; Dyke, A.S.; Shakun, J.D.; Carlson, A.E.; Clark, J.; Wohlfarth, B.; Mitrovica, J.X.; Hostetler, S.W.; McCabe, A.M.

2009-01-01

We used 5704 14C, 10Be, and 3He ages that span the interval from 10,000 to 50,000 years ago (10 to 50 ka) to constrain the timing of the Last Glacial Maximum (LGM) in terms of global ice-sheet and mountain-glacier extent. Growth of the ice sheets to their maximum positions occurred between 33.0 and 26.5 ka in response to climate forcing from decreases in northern summer insolation, tropical Pacific sea surface temperatures, and atmospheric CO2. Nearly all ice sheets were at their LGM positions from 26.5 ka to 19 to 20 ka, corresponding to minima in these forcings. The onset of Northern Hemisphere deglaciation 19 to 20 ka was induced by an increase in northern summer insolation, providing the source for an abrupt rise in sea level. The onset of deglaciation of the West Antarctic Ice Sheet occurred between 14 and 15 ka, consistent with evidence that this was the primary source for an abrupt rise in sea level ???14.5 ka.

Maximum physical capacity testing in cancer patients undergoing chemotherapy

DEFF Research Database (Denmark)

Knutsen, L.; Quist, M; Midtgaard, J

2006-01-01

BACKGROUND: Over the past few years there has been a growing interest in the field of physical exercise in rehabilitation of cancer patients, leading to requirements for objective maximum physical capacity measurement (maximum oxygen uptake (VO(2max)) and one-repetition maximum (1RM)) to determin...... early in the treatment process. However, the patients were self-referred and thus highly motivated and as such are not necessarily representative of the whole population of cancer patients treated with chemotherapy....... in performing maximum physical capacity tests as these motivated them through self-perceived competitiveness and set a standard that served to encourage peak performance. CONCLUSION: The positive attitudes in this sample towards maximum physical capacity open the possibility of introducing physical testing...

Value of volume measurements in evaluating abdominal aortic aneurysms growth rate and need for surgical treatment

Energy Technology Data Exchange (ETDEWEB)

Kontopodis, Nikolaos, E-mail: kontopodisn@yahoo.gr [Department of Vascular Surgery, University of Crete Medical School, Heraklion (Greece); Metaxa, Eleni, E-mail: emmetaxa@gmail.com [Institute of Applied and Computational Mathematics, Foundation for Research and Technology-Hellas, Heraklion, Crete (Greece); Papaharilaou, Yannis, E-mail: yannisp@iacm.forth.gr [Institute of Applied and Computational Mathematics, Foundation for Research and Technology-Hellas, Heraklion, Crete (Greece); Georgakarakos, Efstratios, E-mail: efstratiosgeorg@gmail.com [Vascular Surgery Department, “Demokritus” University of Thrace Medical School, Alexandroupolis (Greece); Tsetis, Dimitris, E-mail: tsetis@med.uoc.gr [Interventional Radiology Unit, Department of Radiology, University of Crete Medical School, Heraklion, Crete (Greece); Ioannou, Christos V., E-mail: ioannou@med.uoc.gr [Department of Vascular Surgery, University of Crete Medical School, Heraklion (Greece)

2014-07-15

Purpose: To examine whether indices other than the traditionally used abdominal aortic aneurysm (AAA) maximum diameter, such as AAA volume, intraluminal thrombus (ILT) thickness and ILT volume, may be superior to evaluate aneurismal enlargement. Materials and methods: Thirty-four small AAAs (initially presenting a maximum diameter <5.5 cm which is the threshold for surgical repair) with an initial and a follow-up CT were examined. Median increase and percentile annual change of these variables was calculated. Correlation between growth rates as determined by the new indices under evaluation and those of maximum diameter were assessed. AAAs were divided according to outcome (surveillance vs. elective repair after follow-up which is based on the maximum diameter criterion) and according to growth rate (high vs. low) based on four indices. Contingency between groups of high/low growth rate regarding each of the four indices on one hand and those regarding need for surgical repair on the other was assessed. Results: A strong correlation between growth rates of maximum diameter and those of AAA and ILT volumes could be established. Evaluation of contingency between groups of outcome and those of growth rate revealed significant associations only for AAA and ILT volumes. Subsequently AAAs with a rapid volumetric increase over time had a likelihood ratio of 10 to be operated compared to those with a slower enlargement. Regarding increase of maximum diameter, likelihood ratio between AAAs with rapid and those with slow expansion was only 3. Conclusion: Growth rate of aneurysms regarding 3Dimensional indices of AAA and ILT volumes is significantly associated with the need for surgical intervention while the same does not hold for growth rates determined by 2Dimensional indices of maximum diameter and ILT thickness.

Value of volume measurements in evaluating abdominal aortic aneurysms growth rate and need for surgical treatment

International Nuclear Information System (INIS)

Kontopodis, Nikolaos; Metaxa, Eleni; Papaharilaou, Yannis; Georgakarakos, Efstratios; Tsetis, Dimitris; Ioannou, Christos V.

2014-01-01

Purpose: To examine whether indices other than the traditionally used abdominal aortic aneurysm (AAA) maximum diameter, such as AAA volume, intraluminal thrombus (ILT) thickness and ILT volume, may be superior to evaluate aneurismal enlargement. Materials and methods: Thirty-four small AAAs (initially presenting a maximum diameter <5.5 cm which is the threshold for surgical repair) with an initial and a follow-up CT were examined. Median increase and percentile annual change of these variables was calculated. Correlation between growth rates as determined by the new indices under evaluation and those of maximum diameter were assessed. AAAs were divided according to outcome (surveillance vs. elective repair after follow-up which is based on the maximum diameter criterion) and according to growth rate (high vs. low) based on four indices. Contingency between groups of high/low growth rate regarding each of the four indices on one hand and those regarding need for surgical repair on the other was assessed. Results: A strong correlation between growth rates of maximum diameter and those of AAA and ILT volumes could be established. Evaluation of contingency between groups of outcome and those of growth rate revealed significant associations only for AAA and ILT volumes. Subsequently AAAs with a rapid volumetric increase over time had a likelihood ratio of 10 to be operated compared to those with a slower enlargement. Regarding increase of maximum diameter, likelihood ratio between AAAs with rapid and those with slow expansion was only 3. Conclusion: Growth rate of aneurysms regarding 3Dimensional indices of AAA and ILT volumes is significantly associated with the need for surgical intervention while the same does not hold for growth rates determined by 2Dimensional indices of maximum diameter and ILT thickness

MAXIMUM PRINCIPLE FOR SUBSONIC FLOW WITH VARIABLE ENTROPY

Directory of Open Access Journals (Sweden)

B. Sizykh Grigory

2017-01-01

Full Text Available Maximum principle for subsonic flow is fair for stationary irrotational subsonic gas flows. According to this prin- ciple, if the value of the velocity is not constant everywhere, then its maximum is achieved on the boundary and only on the boundary of the considered domain. This property is used when designing form of an aircraft with a maximum critical val- ue of the Mach number: it is believed that if the local Mach number is less than unit in the incoming flow and on the body surface, then the Mach number is less then unit in all points of flow. The known proof of maximum principle for subsonic flow is based on the assumption that in the whole considered area of the flow the pressure is a function of density. For the ideal and perfect gas (the role of diffusion is negligible, and the Mendeleev-Clapeyron law is fulfilled, the pressure is a function of density if entropy is constant in the entire considered area of the flow. Shows an example of a stationary sub- sonic irrotational flow, in which the entropy has different values on different stream lines, and the pressure is not a function of density. The application of the maximum principle for subsonic flow with respect to such a flow would be unreasonable. This example shows the relevance of the question about the place of the points of maximum value of the velocity, if the entropy is not a constant. To clarify the regularities of the location of these points, was performed the analysis of the com- plete Euler equations (without any simplifying assumptions in 3-D case. The new proof of the maximum principle for sub- sonic flow was proposed. This proof does not rely on the assumption that the pressure is a function of density. Thus, it is shown that the maximum principle for subsonic flow is true for stationary subsonic irrotational flows of ideal perfect gas with variable entropy.

Maximum power point tracker based on fuzzy logic

International Nuclear Information System (INIS)

Daoud, A.; Midoun, A.

2006-01-01

The solar energy is used as power source in photovoltaic power systems and the need for an intelligent power management system is important to obtain the maximum power from the limited solar panels. With the changing of the sun illumination due to variation of angle of incidence of sun radiation and of the temperature of the panels, Maximum Power Point Tracker (MPPT) enables optimization of solar power generation. The MPPT is a sub-system designed to extract the maximum power from a power source. In the case of solar panels power source. the maximum power point varies as a result of changes in its electrical characteristics which in turn are functions of radiation dose, temperature, ageing and other effects. The MPPT maximum the power output from panels for a given set of conditions by detecting the best working point of the power characteristic and then controls the current through the panels or the voltage across them. Many MPPT methods have been reported in literature. These techniques of MPPT can be classified into three main categories that include: lookup table methods, hill climbing methods and computational methods. The techniques vary according to the degree of sophistication, processing time and memory requirements. The perturbation and observation algorithm (hill climbing technique) is commonly used due to its ease of implementation, and relative tracking efficiency. However, it has been shown that when the insolation changes rapidly, the perturbation and observation method is slow to track the maximum power point. In recent years, the fuzzy controllers are used for maximum power point tracking. This method only requires the linguistic control rules for maximum power point, the mathematical model is not required and therefore the implementation of this control method is easy to real control system. In this paper, we we present a simple robust MPPT using fuzzy set theory where the hardware consists of the microchip's microcontroller unit control card and

Maximum entropy methods

International Nuclear Information System (INIS)

Ponman, T.J.

1984-01-01

For some years now two different expressions have been in use for maximum entropy image restoration and there has been some controversy over which one is appropriate for a given problem. Here two further entropies are presented and it is argued that there is no single correct algorithm. The properties of the four different methods are compared using simple 1D simulations with a view to showing how they can be used together to gain as much information as possible about the original object. (orig.)

Two-Stage Maximum Likelihood Estimation (TSMLE for MT-CDMA Signals in the Indoor Environment

Directory of Open Access Journals (Sweden)

Sesay Abu B

2004-01-01

Full Text Available This paper proposes a two-stage maximum likelihood estimation (TSMLE technique suited for multitone code division multiple access (MT-CDMA system. Here, an analytical framework is presented in the indoor environment for determining the average bit error rate (BER of the system, over Rayleigh and Ricean fading channels. The analytical model is derived for quadrature phase shift keying (QPSK modulation technique by taking into account the number of tones, signal bandwidth (BW, bit rate, and transmission power. Numerical results are presented to validate the analysis, and to justify the approximations made therein. Moreover, these results are shown to agree completely with those obtained by simulation.

Maximum entropy deconvolution of low count nuclear medicine images

International Nuclear Information System (INIS)

McGrath, D.M.

1998-12-01

Maximum entropy is applied to the problem of deconvolving nuclear medicine images, with special consideration for very low count data. The physics of the formation of scintigraphic images is described, illustrating the phenomena which degrade planar estimates of the tracer distribution. Various techniques which are used to restore these images are reviewed, outlining the relative merits of each. The development and theoretical justification of maximum entropy as an image processing technique is discussed. Maximum entropy is then applied to the problem of planar deconvolution, highlighting the question of the choice of error parameters for low count data. A novel iterative version of the algorithm is suggested which allows the errors to be estimated from the predicted Poisson mean values. This method is shown to produce the exact results predicted by combining Poisson statistics and a Bayesian interpretation of the maximum entropy approach. A facility for total count preservation has also been incorporated, leading to improved quantification. In order to evaluate this iterative maximum entropy technique, two comparable methods, Wiener filtering and a novel Bayesian maximum likelihood expectation maximisation technique, were implemented. The comparison of results obtained indicated that this maximum entropy approach may produce equivalent or better measures of image quality than the compared methods, depending upon the accuracy of the system model used. The novel Bayesian maximum likelihood expectation maximisation technique was shown to be preferable over many existing maximum a posteriori methods due to its simplicity of implementation. A single parameter is required to define the Bayesian prior, which suppresses noise in the solution and may reduce the processing time substantially. Finally, maximum entropy deconvolution was applied as a pre-processing step in single photon emission computed tomography reconstruction of low count data. Higher contrast results were

Maximum Principles for Discrete and Semidiscrete Reaction-Diffusion Equation

Directory of Open Access Journals (Sweden)

Petr Stehlík

2015-01-01

Full Text Available We study reaction-diffusion equations with a general reaction function f on one-dimensional lattices with continuous or discrete time ux′  (or  Δtux=k(ux-1-2ux+ux+1+f(ux, x∈Z. We prove weak and strong maximum and minimum principles for corresponding initial-boundary value problems. Whereas the maximum principles in the semidiscrete case (continuous time exhibit similar features to those of fully continuous reaction-diffusion model, in the discrete case the weak maximum principle holds for a smaller class of functions and the strong maximum principle is valid in a weaker sense. We describe in detail how the validity of maximum principles depends on the nonlinearity and the time step. We illustrate our results on the Nagumo equation with the bistable nonlinearity.

Minimal length, Friedmann equations and maximum density

Energy Technology Data Exchange (ETDEWEB)

Awad, Adel [Center for Theoretical Physics, British University of Egypt,Sherouk City 11837, P.O. Box 43 (Egypt); Department of Physics, Faculty of Science, Ain Shams University,Cairo, 11566 (Egypt); Ali, Ahmed Farag [Centre for Fundamental Physics, Zewail City of Science and Technology,Sheikh Zayed, 12588, Giza (Egypt); Department of Physics, Faculty of Science, Benha University,Benha, 13518 (Egypt)

2014-06-16

Inspired by Jacobson’s thermodynamic approach, Cai et al. have shown the emergence of Friedmann equations from the first law of thermodynamics. We extend Akbar-Cai derivation http://dx.doi.org/10.1103/PhysRevD.75.084003 of Friedmann equations to accommodate a general entropy-area law. Studying the resulted Friedmann equations using a specific entropy-area law, which is motivated by the generalized uncertainty principle (GUP), reveals the existence of a maximum energy density closed to Planck density. Allowing for a general continuous pressure p(ρ,a) leads to bounded curvature invariants and a general nonsingular evolution. In this case, the maximum energy density is reached in a finite time and there is no cosmological evolution beyond this point which leaves the big bang singularity inaccessible from a spacetime prospective. The existence of maximum energy density and a general nonsingular evolution is independent of the equation of state and the spacial curvature k. As an example we study the evolution of the equation of state p=ωρ through its phase-space diagram to show the existence of a maximum energy which is reachable in a finite time.

Probabilistic maximum-value wind prediction for offshore environments

DEFF Research Database (Denmark)

Staid, Andrea; Pinson, Pierre; Guikema, Seth D.

2015-01-01

statistical models to predict the full distribution of the maximum-value wind speeds in a 3 h interval. We take a detailed look at the performance of linear models, generalized additive models and multivariate adaptive regression splines models using meteorological covariates such as gust speed, wind speed......, convective available potential energy, Charnock, mean sea-level pressure and temperature, as given by the European Center for Medium-Range Weather Forecasts forecasts. The models are trained to predict the mean value of maximum wind speed, and the residuals from training the models are used to develop...... the full probabilistic distribution of maximum wind speed. Knowledge of the maximum wind speed for an offshore location within a given period can inform decision-making regarding turbine operations, planned maintenance operations and power grid scheduling in order to improve safety and reliability...

Halo-independence with quantified maximum entropy at DAMA/LIBRA

Energy Technology Data Exchange (ETDEWEB)

Fowlie, Andrew, E-mail: andrew.j.fowlie@googlemail.com [ARC Centre of Excellence for Particle Physics at the Tera-scale, Monash University, Melbourne, Victoria 3800 (Australia)

2017-10-01

Using the DAMA/LIBRA anomaly as an example, we formalise the notion of halo-independence in the context of Bayesian statistics and quantified maximum entropy. We consider an infinite set of possible profiles, weighted by an entropic prior and constrained by a likelihood describing noisy measurements of modulated moments by DAMA/LIBRA. Assuming an isotropic dark matter (DM) profile in the galactic rest frame, we find the most plausible DM profiles and predictions for unmodulated signal rates at DAMA/LIBRA. The entropic prior contains an a priori unknown regularisation factor, β, that describes the strength of our conviction that the profile is approximately Maxwellian. By varying β, we smoothly interpolate between a halo-independent and a halo-dependent analysis, thus exploring the impact of prior information about the DM profile.

Characterizing graphs of maximum matching width at most 2

DEFF Research Database (Denmark)

Jeong, Jisu; Ok, Seongmin; Suh, Geewon

2017-01-01

The maximum matching width is a width-parameter that is de ned on a branch-decomposition over the vertex set of a graph. The size of a maximum matching in the bipartite graph is used as a cut-function. In this paper, we characterize the graphs of maximum matching width at most 2 using the minor o...

The Hengill geothermal area, Iceland: variation of temperature gradients deduced from the maximum depth of seismogenesis

Science.gov (United States)

Foulger, G.R.

1995-01-01

Given a uniform lithology and strain rate and a full seismic data set, the maximum depth of earthquakes may be viewed to a first order as an isotherm. These conditions are approached at the Hengill geothermal area, S. Iceland, a dominantly basaltic area. The temperature at which seismic failure ceases for the strain rates likely at the Hengill geothermal area is determined by analogy with oceanic crust, and is about 650 ?? 50??C. The topographies of the top and bottom of the seismogenic layer were mapped using 617 earthquakes. The thickness of the seismogenic layer is roughly constant and about 3 km. A shallow, aseismic, low-velocity volume within the spreading plate boundary that crosses the area occurs above the top of the seismogenic layer and is interpreted as an isolated body of partial melt. The base of the seismogenic layer has a maximum depth of about 6.5 km beneath the spreading axis and deepens to about 7 km beneath a transform zone in the south of the area. -from Author

The Maximum Resource Bin Packing Problem

DEFF Research Database (Denmark)

Boyar, J.; Epstein, L.; Favrholdt, L.M.

2006-01-01

Usually, for bin packing problems, we try to minimize the number of bins used or in the case of the dual bin packing problem, maximize the number or total size of accepted items. This paper presents results for the opposite problems, where we would like to maximize the number of bins used...... algorithms, First-Fit-Increasing and First-Fit-Decreasing for the maximum resource variant of classical bin packing. For the on-line variant, we define maximum resource variants of classical and dual bin packing. For dual bin packing, no on-line algorithm is competitive. For classical bin packing, we find...

Maximum entropy analysis of EGRET data

DEFF Research Database (Denmark)

Pohl, M.; Strong, A.W.

1997-01-01

EGRET data are usually analysed on the basis of the Maximum-Likelihood method \\cite{ma96} in a search for point sources in excess to a model for the background radiation (e.g. \\cite{hu97}). This method depends strongly on the quality of the background model, and thus may have high systematic unce...... uncertainties in region of strong and uncertain background like the Galactic Center region. Here we show images of such regions obtained by the quantified Maximum-Entropy method. We also discuss a possible further use of MEM in the analysis of problematic regions of the sky....

Density estimation by maximum quantum entropy

International Nuclear Information System (INIS)

Silver, R.N.; Wallstrom, T.; Martz, H.F.

1993-01-01

A new Bayesian method for non-parametric density estimation is proposed, based on a mathematical analogy to quantum statistical physics. The mathematical procedure is related to maximum entropy methods for inverse problems and image reconstruction. The information divergence enforces global smoothing toward default models, convexity, positivity, extensivity and normalization. The novel feature is the replacement of classical entropy by quantum entropy, so that local smoothing is enforced by constraints on differential operators. The linear response of the estimate is proportional to the covariance. The hyperparameters are estimated by type-II maximum likelihood (evidence). The method is demonstrated on textbook data sets

Maximum power point tracking-based control algorithm for PMSG wind generation system without mechanical sensors

International Nuclear Information System (INIS)

Hong, Chih-Ming; Chen, Chiung-Hsing; Tu, Chia-Sheng

2013-01-01

Highlights: ► This paper presents MPPT based control for optimal wind energy capture using RBFN. ► MPSO is adopted to adjust the learning rates to improve the learning capability. ► This technique can maintain the system stability and reach the desired performance. ► The EMF in the rotating reference frame is utilized in order to estimate speed. - Abstract: This paper presents maximum-power-point-tracking (MPPT) based control algorithms for optimal wind energy capture using radial basis function network (RBFN) and a proposed torque observer MPPT algorithm. The design of a high-performance on-line training RBFN using back-propagation learning algorithm with modified particle swarm optimization (MPSO) regulating controller for the sensorless control of a permanent magnet synchronous generator (PMSG). The MPSO is adopted in this study to adapt the learning rates in the back-propagation process of the RBFN to improve the learning capability. The PMSG is controlled by the loss-minimization control with MPPT below the base speed, which corresponds to low and high wind speed, and the maximum energy can be captured from the wind. Then the observed disturbance torque is feed-forward to increase the robustness of the PMSG system

Multiphase radon generation and transport in porous materials

International Nuclear Information System (INIS)

Rogers, V.C.; Nielson, K.K.

1991-01-01

Radon generation and transport in porous materials involve solid, liquid, and gas phases in the processes of emanation, diffusion, advection, absorption, and adsorption. Oversimplifications, such as representing moist soil systems by air-phase emanation and transport models, cause theoretical inconsistencies and biases in resulting calculations. Detailed Rn rate balance equations for solid, liquid, and gas phases were analyzed and combined using phase equilibrium constants to derive a single diffusive-advective rate balance equation in the traditional form. The emanation, diffusion, and permeability coefficients in the new equation have expanded definitions and interpretations to include Rn phase transfer. Radon adsorption was characterized by an exponential moisture dependence, and diffusion and permeability constants utilized previous moisture relationships. Correct boundary and interface conditions were defined, and the unified theoretical approach was applied to field data from a diffusion-dominated system and to laboratory data from an advection-dominated system. Measured 222 Rn fluxes and concentrations validated the modeled values within the measurement variability in both applications

Tritium migration studies at the Nevada Test Site

International Nuclear Information System (INIS)

Schulz, R.K.; Weaver, M.O.

1993-05-01

Emanation of tritium from waste containers is a commonly known phenomenon. Release of tritium from buried waste packages was anticipated; therefore, a research program was developed to study both the rate of tritium release from buried containers and subsequent migration of tritium through soil. Migration of tritium away from low-level radioactive wastes buried in Area 5 of the Nevada Test Site was studied. Four distinct disposal events were investigated. The oldest burial event studied was a 1976 emplacement of 3.5 million curies of tritium in a shallow land burial trench. In another event, 248 thousand curies of tritium was disposed of in an overpack emplaced 6 m below the floor of a low-level waste disposal pit. Measurement of the emanation rate of tritium out of 55 gallon drums to the overpack was studied, and an annual doubling of the emanation rate over a seven year period, ending in 1990, was found. In a third study, upward tritium migration in the soil, resulting in releases in the atmosphere were observed in a greater confinement disposal test. Releases of tritium to the atmosphere were found to be insignificant. The fourth event consisted of burial of 2.2 million curies of tritium in a greater confinement disposal operation. Emanation of tritium from the buried containers has been increasing since disposal, but no significant migration was found four years following backfilling of the disposal hole

Heat release rate of wood-plastic composites

Science.gov (United States)

N. M. Stark; R. H. White; C. M. Clemons

1997-01-01

Wood-plastic composites are becoming more important as a material that fulfills recycling needs. In this study, fire performance tests were conducted on several compositions of wood and plastic materials using the Ohio State University rate of heat release apparatus. Test results included five-minute average heat release rate in kW/m2 (HRR avg) and maximum heat release...

The numerical evaluation of maximum-likelihood estimates of the parameters for a mixture of normal distributions from partially identified samples

Science.gov (United States)

Walker, H. F.

1976-01-01

Likelihood equations determined by the two types of samples which are necessary conditions for a maximum-likelihood estimate are considered. These equations, suggest certain successive-approximations iterative procedures for obtaining maximum-likelihood estimates. These are generalized steepest ascent (deflected gradient) procedures. It is shown that, with probability 1 as N sub 0 approaches infinity (regardless of the relative sizes of N sub 0 and N sub 1, i=1,...,m), these procedures converge locally to the strongly consistent maximum-likelihood estimates whenever the step size is between 0 and 2. Furthermore, the value of the step size which yields optimal local convergence rates is bounded from below by a number which always lies between 1 and 2.

Tracking the maximum efficiency point for the FC system based on extremum seeking scheme to control the air flow

International Nuclear Information System (INIS)

Bizon, Nicu

2014-01-01

Highlights: • The Maximum Efficiency Point (MEP) is tracked based on air flow rate. • The proposed Extremum Seeking (ES) control assures high performances. • About 10 kW/s search speed and 99.99% stationary accuracy can be obtained. • The energy efficiency increases with 3–12%, according to the power losses. • The control strategy is robust based on self-optimizing ES scheme proposed. - Abstract: An advanced control of the air compressor for the Proton Exchange Membrane Fuel Cell (PEMFC) system is proposed in this paper based on Extremum Seeking (ES) control scheme. The FC net power is mainly depended on the air and hydrogen flow rate and pressure, and heat and water management. This paper proposes to compute the optimal value for the air flow rate based on the advanced ES control scheme in order to maximize the FC net power. In this way, the Maximum Efficiency Point (MEP) will be tracked in real time, with about 10 kW/s search speed and a stationary accuracy of 0.99. Thus, energy efficiency will be close to the maximum value that can be obtained for a given PEMFC stack and compressor group under dynamic load. It is shown that the MEP tracking allows an increasing of the FC net power with 3–12%, depending on the percentage of the FC power supplied to the compressor and the level of the load power. Simulations shows that the performances mentioned above are effective

Analogue of Pontryagin's maximum principle for multiple integrals minimization problems

OpenAIRE

Mikhail, Zelikin

2016-01-01

The theorem like Pontryagin's maximum principle for multiple integrals is proved. Unlike the usual maximum principle, the maximum should be taken not over all matrices, but only on matrices of rank one. Examples are given.

Microprocessor Controlled Maximum Power Point Tracker for Photovoltaic Application

International Nuclear Information System (INIS)

Jiya, J. D.; Tahirou, G.

2002-01-01

This paper presents a microprocessor controlled maximum power point tracker for photovoltaic module. Input current and voltage are measured and multiplied within the microprocessor, which contains an algorithm to seek the maximum power point. The duly cycle of the DC-DC converter, at which the maximum power occurs is obtained, noted and adjusted. The microprocessor constantly seeks for improvement of obtained power by varying the duty cycle

Measurement of the Depth of Maximum of Extensive Air Showers above 10^18 eV

Energy Technology Data Exchange (ETDEWEB)

Abraham, J.; /Buenos Aires, CONICET; Abreu, P.; /Lisbon, IST; Aglietta, M.; /Turin U. /INFN, Turin; Ahn, E.J.; /Fermilab; Allard, D.; /APC, Paris; Allekotte, I.; /Centro Atomico Bariloche /Buenos Aires, CONICET; Allen, J.; /New York U.; Alvarez-Muniz, J.; /Santiago de Compostela U.; Ambrosio, M.; /Naples U.; Anchordoqui, L.; /Wisconsin U., Milwaukee; Andringa, S.; /Lisbon, IST /Boskovic Inst., Zagreb

2010-02-01

We describe the measurement of the depth of maximum, X{sub max}, of the longitudinal development of air showers induced by cosmic rays. Almost 4000 events above 10{sup 18} eV observed by the fluorescence detector of the Pierre Auger Observatory in coincidence with at least one surface detector station are selected for the analysis. The average shower maximum was found to evolve with energy at a rate of (106{sub -21}{sup +35}) g/cm{sup 2}/decade below 10{sup 18.24 {+-} 0.05}eV, and (24 {+-} 3) g/cm{sup 2}/decade above this energy. The measured shower-to-shower fluctuations decrease from about 55 to 26 g/cm{sup 2}. The interpretation of these results in terms of the cosmic ray mass composition is briefly discussed.

Maximum entropy reconstructions for crystallographic imaging; Cristallographie et reconstruction d`images par maximum d`entropie

Energy Technology Data Exchange (ETDEWEB)

Papoular, R

1997-07-01

The Fourier Transform is of central importance to Crystallography since it allows the visualization in real space of tridimensional scattering densities pertaining to physical systems from diffraction data (powder or single-crystal diffraction, using x-rays, neutrons, electrons or else). In turn, this visualization makes it possible to model and parametrize these systems, the crystal structures of which are eventually refined by Least-Squares techniques (e.g., the Rietveld method in the case of Powder Diffraction). The Maximum Entropy Method (sometimes called MEM or MaxEnt) is a general imaging technique, related to solving ill-conditioned inverse problems. It is ideally suited for tackling undetermined systems of linear questions (for which the number of variables is much larger than the number of equations). It is already being applied successfully in Astronomy, Radioastronomy and Medical Imaging. The advantages of using MAXIMUM Entropy over conventional Fourier and `difference Fourier` syntheses stem from the following facts: MaxEnt takes the experimental error bars into account; MaxEnt incorporate Prior Knowledge (e.g., the positivity of the scattering density in some instances); MaxEnt allows density reconstructions from incompletely phased data, as well as from overlapping Bragg reflections; MaxEnt substantially reduces truncation errors to which conventional experimental Fourier reconstructions are usually prone. The principles of Maximum Entropy imaging as applied to Crystallography are first presented. The method is then illustrated by a detailed example specific to Neutron Diffraction: the search for proton in solids. (author). 17 refs.

Comprehensive performance analyses and optimization of the irreversible thermodynamic cycle engines (TCE) under maximum power (MP) and maximum power density (MPD) conditions

International Nuclear Information System (INIS)

Gonca, Guven; Sahin, Bahri; Ust, Yasin; Parlak, Adnan

2015-01-01

This paper presents comprehensive performance analyses and comparisons for air-standard irreversible thermodynamic cycle engines (TCE) based on the power output, power density, thermal efficiency, maximum dimensionless power output (MP), maximum dimensionless power density (MPD) and maximum thermal efficiency (MEF) criteria. Internal irreversibility of the cycles occurred during the irreversible-adiabatic processes is considered by using isentropic efficiencies of compression and expansion processes. The performances of the cycles are obtained by using engine design parameters such as isentropic temperature ratio of the compression process, pressure ratio, stroke ratio, cut-off ratio, Miller cycle ratio, exhaust temperature ratio, cycle temperature ratio and cycle pressure ratio. The effects of engine design parameters on the maximum and optimal performances are investigated. - Highlights: • Performance analyses are conducted for irreversible thermodynamic cycle engines. • Comprehensive computations are performed. • Maximum and optimum performances of the engines are shown. • The effects of design parameters on performance and power density are examined. • The results obtained may be guidelines to the engine designers

Shower maximum detector for SDC calorimetry

International Nuclear Information System (INIS)

Ernwein, J.

1994-01-01

A prototype for the SDC end-cap (EM) calorimeter complete with a pre-shower and a shower maximum detector was tested in beams of electrons and Π's at CERN by an SDC subsystem group. The prototype was manufactured from scintillator tiles and strips read out with 1 mm diameter wave-length shifting fibers. The design and construction of the shower maximum detector is described, and results of laboratory tests on light yield and performance of the scintillator-fiber system are given. Preliminary results on energy and position measurements with the shower max detector in the test beam are shown. (authors). 4 refs., 5 figs

GAS SURFACE DENSITY, STAR FORMATION RATE SURFACE DENSITY, AND THE MAXIMUM MASS OF YOUNG STAR CLUSTERS IN A DISK GALAXY. II. THE GRAND-DESIGN GALAXY M51

International Nuclear Information System (INIS)

González-Lópezlira, Rosa A.; Pflamm-Altenburg, Jan; Kroupa, Pavel

2013-01-01

We analyze the relationship between maximum cluster mass and surface densities of total gas (Σ gas ), molecular gas (Σ H 2 ), neutral gas (Σ H I ), and star formation rate (Σ SFR ) in the grand-design galaxy M51, using published gas data and a catalog of masses, ages, and reddenings of more than 1800 star clusters in its disk, of which 223 are above the cluster mass distribution function completeness limit. By comparing the two-dimensional distribution of cluster masses and gas surface densities, we find for clusters older than 25 Myr that M 3rd ∝Σ H I 0.4±0.2 , whereM 3rd is the median of the five most massive clusters. There is no correlation withΣ gas ,Σ H2 , orΣ SFR . For clusters younger than 10 Myr, M 3rd ∝Σ H I 0.6±0.1 and M 3rd ∝Σ gas 0.5±0.2 ; there is no correlation with either Σ H 2 orΣ SFR . The results could hardly be more different from those found for clusters younger than 25 Myr in M33. For the flocculent galaxy M33, there is no correlation between maximum cluster mass and neutral gas, but we have determined M 3rd ∝Σ gas 3.8±0.3 , M 3rd ∝Σ H 2 1.2±0.1 , and M 3rd ∝Σ SFR 0.9±0.1 . For the older sample in M51, the lack of tight correlations is probably due to the combination of strong azimuthal variations in the surface densities of gas and star formation rate, and the cluster ages. These two facts mean that neither the azimuthal average of the surface densities at a given radius nor the surface densities at the present-day location of a stellar cluster represent the true surface densities at the place and time of cluster formation. In the case of the younger sample, even if the clusters have not yet traveled too far from their birth sites, the poor resolution of the radio data compared to the physical sizes of the clusters results in measuredΣ that are likely quite diluted compared to the actual densities relevant for the formation of the clusters.

Maximum Power Point Tracking in Variable Speed Wind Turbine Based on Permanent Magnet Synchronous Generator Using Maximum Torque Sliding Mode Control Strategy

Institute of Scientific and Technical Information of China (English)

Esmaeil Ghaderi; Hossein Tohidi; Behnam Khosrozadeh

2017-01-01

The present study was carried out in order to track the maximum power point in a variable speed turbine by minimizing electromechanical torque changes using a sliding mode control strategy.In this strategy,fhst,the rotor speed is set at an optimal point for different wind speeds.As a result of which,the tip speed ratio reaches an optimal point,mechanical power coefficient is maximized,and wind turbine produces its maximum power and mechanical torque.Then,the maximum mechanical torque is tracked using electromechanical torque.In this technique,tracking error integral of maximum mechanical torque,the error,and the derivative of error are used as state variables.During changes in wind speed,sliding mode control is designed to absorb the maximum energy from the wind and minimize the response time of maximum power point tracking (MPPT).In this method,the actual control input signal is formed from a second order integral operation of the original sliding mode control input signal.The result of the second order integral in this model includes control signal integrity,full chattering attenuation,and prevention from large fluctuations in the power generator output.The simulation results,calculated by using MATLAB/m-file software,have shown the effectiveness of the proposed control strategy for wind energy systems based on the permanent magnet synchronous generator (PMSG).

Evaluation of adaptation to visually induced motion sickness based on the maximum cross-correlation between pulse transmission time and heart rate

Directory of Open Access Journals (Sweden)

Chiba Shigeru

2007-09-01

Full Text Available Abstract Background Computer graphics and virtual reality techniques are useful to develop automatic and effective rehabilitation systems. However, a kind of virtual environment including unstable visual images presented to wide field screen or a head mounted display tends to induce motion sickness. The motion sickness induced in using a rehabilitation system not only inhibits effective training but also may harm patients' health. There are few studies that have objectively evaluated the effects of the repetitive exposures to these stimuli on humans. The purpose of this study is to investigate the adaptation to visually induced motion sickness by physiological data. Methods An experiment was carried out in which the same video image was presented to human subjects three times. We evaluated changes of the intensity of motion sickness they suffered from by a subjective score and the physiological index ρmax, which is defined as the maximum cross-correlation coefficient between heart rate and pulse wave transmission time and is considered to reflect the autonomic nervous activity. Results The results showed adaptation to visually-induced motion sickness by the repetitive presentation of the same image both in the subjective and the objective indices. However, there were some subjects whose intensity of sickness increased. Thus, it was possible to know the part in the video image which related to motion sickness by analyzing changes in ρmax with time. Conclusion The physiological index, ρmax, will be a good index for assessing the adaptation process to visually induced motion sickness and may be useful in checking the safety of rehabilitation systems with new image technologies.

32 CFR 842.35 - Depreciation and maximum allowances.

Science.gov (United States)

2010-07-01

... 32 National Defense 6 2010-07-01 2010-07-01 false Depreciation and maximum allowances. 842.35... LITIGATION ADMINISTRATIVE CLAIMS Personnel Claims (31 U.S.C. 3701, 3721) § 842.35 Depreciation and maximum allowances. The military services have jointly established the “Allowance List-Depreciation Guide” to...

13 CFR 120.213 - What fixed interest rates may a Lender charge?

Science.gov (United States)

2010-01-01

... Lender charge? 120.213 Section 120.213 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION... have a reasonable fixed interest rate. SBA periodically publishes the maximum allowable rate in the... government determines the interest rate on direct loans. SBA publishes the rate periodically in the Federal...

Investigation of some factors affecting on release of radon-222 from phosphogypsum waste associated with phosphate ore processing.

Science.gov (United States)

Hilal, M A; El Afifi, E M; Nayl, A A

2015-07-01

The aim of this study is oriented to investigate the influence of some physicochemical factors such as radium distribution, grain size, moisture content and chemical constituents on releases of radon-222 from the accumulated phosphogypsum (PG) waste. The emanation fraction, activity concentration in the pore and the surface exhalation rate of radon-222 in the bulk PG waste are 34.5 ± 0.3%, 238.6 ± 7.8 kBq m(-3) and 213 ± 6.9 mBq m(-2) s(-1), respectively. These values were varied and enhanced slightly in the fine grain sizes (F1 factor of 1.05 folds compared to the bulk residue. It was also found that release of radon from residue PG waste was controlled positively by radium (Ra-226), calcium (CaSO4) and strontium (SrO). About 67% of radon release attributed to the grain size below 0.5 mm, while 33% due to the large grain size above 0.5 mm. The emanation fraction of Rn-222 is increased with moisture content and the maximum emanation is ∼43% of moisture of 3-8%. It reduced slowly with the continuous increase in moisture till 20%. Due to PG waste in situ can be enhancing the background to the surround workers and/or public. Therefore, the environmental negative impacts due to release of Rn-222 can be minimized by legislation to restrict its civil uses, or increasing its moisture to ∼10%, or by the particle size separation of the fine fraction containing the high levels of Ra-226 followed by a suitable chemical treatment or disposal; whereas the low release amount can be diluted and used in cement industry, roads or dam construction. Copyright © 2015 Elsevier Ltd. All rights reserved.

An iterative procedure for obtaining maximum-likelihood estimates of the parameters for a mixture of normal distributions

Science.gov (United States)

Peters, B. C., Jr.; Walker, H. F.

1978-01-01

This paper addresses the problem of obtaining numerically maximum-likelihood estimates of the parameters for a mixture of normal distributions. In recent literature, a certain successive-approximations procedure, based on the likelihood equations, was shown empirically to be effective in numerically approximating such maximum-likelihood estimates; however, the reliability of this procedure was not established theoretically. Here, we introduce a general iterative procedure, of the generalized steepest-ascent (deflected-gradient) type, which is just the procedure known in the literature when the step-size is taken to be 1. We show that, with probability 1 as the sample size grows large, this procedure converges locally to the strongly consistent maximum-likelihood estimate whenever the step-size lies between 0 and 2. We also show that the step-size which yields optimal local convergence rates for large samples is determined in a sense by the 'separation' of the component normal densities and is bounded below by a number between 1 and 2.

Is there a maximum star formation rate in high-redshift galaxies? , , ,

International Nuclear Information System (INIS)

Barger, A. J.; Cowie, L. L.; Chen, C.-C.; Casey, C. M.; Lee, N.; Sanders, D. B.; Williams, J. P.; Owen, F. N.; Wang, W.-H.

2014-01-01

We use the James Clerk Maxwell Telescope's SCUBA-2 camera to image a 400 arcmin 2 area surrounding the GOODS-N field. The 850 μm rms noise ranges from a value of 0.49 mJy in the central region to 3.5 mJy at the outside edge. From these data, we construct an 850 μm source catalog to 2 mJy containing 49 sources detected above the 4σ level. We use an ultradeep (11.5 μJy at 5σ) 1.4 GHz image obtained with the Karl G. Jansky Very Large Array together with observations made with the Submillimeter Array to identify counterparts to the submillimeter galaxies. For most cases of multiple radio counterparts, we can identify the correct counterpart from new and existing Submillimeter Array data. We have spectroscopic redshifts for 62% of the radio sources in the 9' radius highest sensitivity region (556/894) and 67% of the radio sources in the GOODS-N region (367/543). We supplement these with a modest number of additional photometric redshifts in the GOODS-N region (30). We measure millimetric redshifts from the radio to submillimeter flux ratios for the unidentified submillimeter sample, assuming an Arp 220 spectral energy distribution. We find a radio-flux-dependent K – z relation for the radio sources, which we use to estimate redshifts for the remaining radio sources. We determine the star formation rates (SFRs) of the submillimeter sources based on their radio powers and their submillimeter fluxes and find that they agree well. The radio data are deep enough to detect star-forming galaxies with SFRs >2000 M ☉ yr –1 to z ∼ 6. We find galaxies with SFRs up to ∼6000 M ☉ yr –1 over the redshift range z = 1.5-6, but we see evidence for a turn-down in the SFR distribution function above 2000 M ☉ yr –1 .

40 CFR 141.63 - Maximum contaminant levels (MCLs) for microbiological contaminants.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Maximum contaminant levels (MCLs) for microbiological contaminants. 141.63 Section 141.63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Water Regulations: Maximum Contaminant Levels and Maximum Residual Disinfectant Levels § 141.63 Maximum...

Behavior of quenched and tempered steels under high strain rate compression loading

International Nuclear Information System (INIS)

Meyer, L.W.; Seifert, K.; Abdel-Malek, S.

1997-01-01

Two quenched and tempered steels were tested under compression loading at strain rates of ε = 2.10 2 s -1 and ε = 2.10 3 s -1 . By applying the thermal activation theory, the flow stress at very high strain rates of 10 5 to 10 6 s -1 is derived from low temperature and high strain rate tests. Dynamic true stress - true strain behaviour presents, that stress increases with increasing strain until a maximum, then it decreases. Because of the adiabatic process under dynamic loading the maximum flow stress will occur at a lower strain if the strain rate is increased. Considering strain rate, strain hardening, strain rate hardening and strain softening, a constitutive equation with different additive terms is successfully used to describe the behaviour of material under dynamic compression loading. Results are compared with other models of constitutive equations. (orig.)

How to design your stand-by diesel generator unit for maximum reliability

International Nuclear Information System (INIS)

Kauffmann, W.M.

1979-01-01

Critical stand-by power applications, such as in a nuclear plant, or radio support stations, demand exacting guidelines for positive start, rapid acceleration, load acceptance with minimum voltage drop, and quick recovery to rated voltage. The design of medium-speed turbocharged and intercooled diesel-engine-generator for this purpose is considered. Selection of the diesel engine, size, and number of units, from the standpoint of cost, favors minimum number of units with maximum horsepower capability. Four-cycle diesels are available in 16 to 20 cyinders V-configurations, with 200 BMEP (brake mean-effective pressure) continuous and 250 BMEP peaking

Particle Swarm Optimization Based of the Maximum Photovoltaic ...

African Journals Online (AJOL)

Photovoltaic electricity is seen as an important source of renewable energy. The photovoltaic array is an unstable source of power since the peak power point depends on the temperature and the irradiation level. A maximum peak power point tracking is then necessary for maximum efficiency. In this work, a Particle Swarm ...

40 CFR 1045.140 - What is my engine's maximum engine power?

Science.gov (United States)

2010-07-01

...) Maximum engine power for an engine family is generally the weighted average value of maximum engine power... engine family's maximum engine power apply in the following circumstances: (1) For outboard or personal... value for maximum engine power from all the different configurations within the engine family to...

The influence of age on the composting rate of organic material by Eisenia fetida (Oligochaeta

Directory of Open Access Journals (Sweden)

Editorial Office

1995-07-01

Full Text Available One of the main objectives of a vermicomposting plant is to achieve a maximum composting rate of organic waste. Apart from population densities, substrate characteristics and environmental factors, age structure of the population is expected to affect the rate of composting. The composting rate of worms was studied in the laboratory under optimal conditions over a period of 55 days. Growth and sexual maturity were monitored as well as the composting rate during various stages of the life-cycle of Eisenia fetida. The composting rate was initially slow and reached a maximum peak when the worms were pre-clitellate.

42 CFR 409.62 - Lifetime maximum on inpatient psychiatric care.

Science.gov (United States)

2010-10-01

... 42 Public Health 2 2010-10-01 2010-10-01 false Lifetime maximum on inpatient psychiatric care. 409....62 Lifetime maximum on inpatient psychiatric care. There is a lifetime maximum of 190 days on inpatient psychiatric hospital services available to any beneficiary. Therefore, once an individual receives...

Maximum-entropy description of animal movement.

Science.gov (United States)

Fleming, Chris H; Subaşı, Yiğit; Calabrese, Justin M

2015-03-01

We introduce a class of maximum-entropy states that naturally includes within it all of the major continuous-time stochastic processes that have been applied to animal movement, including Brownian motion, Ornstein-Uhlenbeck motion, integrated Ornstein-Uhlenbeck motion, a recently discovered hybrid of the previous models, and a new model that describes central-place foraging. We are also able to predict a further hierarchy of new models that will emerge as data quality improves to better resolve the underlying continuity of animal movement. Finally, we also show that Langevin equations must obey a fluctuation-dissipation theorem to generate processes that fall from this class of maximum-entropy distributions when the constraints are purely kinematic.

Max-Min Optimality of Service Rate Control in Closed Queueing Networks

KAUST Repository

Xia, Li

2013-04-01

In this technical note, we discuss the optimality properties of service rate control in closed Jackson networks. We prove that when the cost function is linear to a particular service rate, the system performance is monotonic w.r.t. (with respect to) that service rate and the optimal value of that service rate can be either maximum or minimum (we call it Max-Min optimality); When the second-order derivative of the cost function w.r.t. a particular service rate is always positive (negative), which makes the cost function strictly convex (concave), the optimal value of such service rate for the performance maximization (minimization) problem can be either maximum or minimum. To the best of our knowledge, this is the most general result for the optimality of service rates in closed Jackson networks and all the previous works only involve the first conclusion. Moreover, our result is also valid for both the state-dependent and load-dependent service rates, under both the time-average and customer-average performance criteria.

Extreme Maximum Land Surface Temperatures.

Science.gov (United States)

Garratt, J. R.

1992-09-01

There are numerous reports in the literature of observations of land surface temperatures. Some of these, almost all made in situ, reveal maximum values in the 50°-70°C range, with a few, made in desert regions, near 80°C. Consideration of a simplified form of the surface energy balance equation, utilizing likely upper values of absorbed shortwave flux (1000 W m2) and screen air temperature (55°C), that surface temperatures in the vicinity of 90°-100°C may occur for dry, darkish soils of low thermal conductivity (0.1-0.2 W m1 K1). Numerical simulations confirm this and suggest that temperature gradients in the first few centimeters of soil may reach 0.5°-1°C mm1 under these extreme conditions. The study bears upon the intrinsic interest of identifying extreme maximum temperatures and yields interesting information regarding the comfort zone of animals (including man).

On Maximum Entropy and Inference

Directory of Open Access Journals (Sweden)

Luigi Gresele

2017-11-01

Full Text Available Maximum entropy is a powerful concept that entails a sharp separation between relevant and irrelevant variables. It is typically invoked in inference, once an assumption is made on what the relevant variables are, in order to estimate a model from data, that affords predictions on all other (dependent variables. Conversely, maximum entropy can be invoked to retrieve the relevant variables (sufficient statistics directly from the data, once a model is identified by Bayesian model selection. We explore this approach in the case of spin models with interactions of arbitrary order, and we discuss how relevant interactions can be inferred. In this perspective, the dimensionality of the inference problem is not set by the number of parameters in the model, but by the frequency distribution of the data. We illustrate the method showing its ability to recover the correct model in a few prototype cases and discuss its application on a real dataset.

Fractal Dimension and Maximum Sunspot Number in Solar Cycle

Directory of Open Access Journals (Sweden)

R.-S. Kim

2006-09-01

Full Text Available The fractal dimension is a quantitative parameter describing the characteristics of irregular time series. In this study, we use this parameter to analyze the irregular aspects of solar activity and to predict the maximum sunspot number in the following solar cycle by examining time series of the sunspot number. For this, we considered the daily sunspot number since 1850 from SIDC (Solar Influences Data analysis Center and then estimated cycle variation of the fractal dimension by using Higuchi's method. We examined the relationship between this fractal dimension and the maximum monthly sunspot number in each solar cycle. As a result, we found that there is a strong inverse relationship between the fractal dimension and the maximum monthly sunspot number. By using this relation we predicted the maximum sunspot number in the solar cycle from the fractal dimension of the sunspot numbers during the solar activity increasing phase. The successful prediction is proven by a good correlation (r=0.89 between the observed and predicted maximum sunspot numbers in the solar cycles.

Automatic maximum entropy spectral reconstruction in NMR

International Nuclear Information System (INIS)

Mobli, Mehdi; Maciejewski, Mark W.; Gryk, Michael R.; Hoch, Jeffrey C.

2007-01-01

Developments in superconducting magnets, cryogenic probes, isotope labeling strategies, and sophisticated pulse sequences together have enabled the application, in principle, of high-resolution NMR spectroscopy to biomolecular systems approaching 1 megadalton. In practice, however, conventional approaches to NMR that utilize the fast Fourier transform, which require data collected at uniform time intervals, result in prohibitively lengthy data collection times in order to achieve the full resolution afforded by high field magnets. A variety of approaches that involve nonuniform sampling have been proposed, each utilizing a non-Fourier method of spectrum analysis. A very general non-Fourier method that is capable of utilizing data collected using any of the proposed nonuniform sampling strategies is maximum entropy reconstruction. A limiting factor in the adoption of maximum entropy reconstruction in NMR has been the need to specify non-intuitive parameters. Here we describe a fully automated system for maximum entropy reconstruction that requires no user-specified parameters. A web-accessible script generator provides the user interface to the system

Stationary neutrino radiation transport by maximum entropy closure

International Nuclear Information System (INIS)

Bludman, S.A.

1994-11-01

The authors obtain the angular distributions that maximize the entropy functional for Maxwell-Boltzmann (classical), Bose-Einstein, and Fermi-Dirac radiation. In the low and high occupancy limits, the maximum entropy closure is bounded by previously known variable Eddington factors that depend only on the flux. For intermediate occupancy, the maximum entropy closure depends on both the occupation density and the flux. The Fermi-Dirac maximum entropy variable Eddington factor shows a scale invariance, which leads to a simple, exact analytic closure for fermions. This two-dimensional variable Eddington factor gives results that agree well with exact (Monte Carlo) neutrino transport calculations out of a collapse residue during early phases of hydrostatic neutron star formation

Toward Improved Rotor-Only Axial Fans—Part II: Design Optimization for Maximum Efficiency

DEFF Research Database (Denmark)

Sørensen, Dan Nørtoft; Thompson, M. C.; Sørensen, Jens Nørkær

2000-01-01

Numerical design optimization of the aerodynamic performance of axial fans is carried out, maximizing the efficiency in a designinterval of flow rates. Tip radius, number of blades, and angular velocity of the rotor are fixed, whereas the hub radius andspanwise distributions of chord length......, stagger angle, and camber angle are varied to find the optimum rotor geometry.Constraints ensure a pressure rise above a specified target and an angle of attack on the blades below stall. The optimizationscheme is used to investigate the dependence of maximum efficiency on the width of the design interval...

Maximum power per VA control of vector controlled interior ...

Indian Academy of Sciences (India)

Thakur Sumeet Singh

2018-04-11

Apr 11, 2018 ... Department of Electrical Engineering, Indian Institute of Technology Delhi, New ... The MPVA operation allows maximum-utilization of the drive-system. ... Permanent magnet motor; unity power factor; maximum VA utilization; ...

Application of maximum entropy to neutron tunneling spectroscopy

International Nuclear Information System (INIS)

Mukhopadhyay, R.; Silver, R.N.

1990-01-01

We demonstrate the maximum entropy method for the deconvolution of high resolution tunneling data acquired with a quasielastic spectrometer. Given a precise characterization of the instrument resolution function, a maximum entropy analysis of lutidine data obtained with the IRIS spectrometer at ISIS results in an effective factor of three improvement in resolution. 7 refs., 4 figs

The maximum economic depth of groundwater abstraction for irrigation

Science.gov (United States)

Bierkens, M. F.; Van Beek, L. P.; de Graaf, I. E. M.; Gleeson, T. P.

2017-12-01

Over recent decades, groundwater has become increasingly important for agriculture. Irrigation accounts for 40% of the global food production and its importance is expected to grow further in the near future. Already, about 70% of the globally abstracted water is used for irrigation, and nearly half of that is pumped groundwater. In many irrigated areas where groundwater is the primary source of irrigation water, groundwater abstraction is larger than recharge and we see massive groundwater head decline in these areas. An important question then is: to what maximum depth can groundwater be pumped for it to be still economically recoverable? The objective of this study is therefore to create a global map of the maximum depth of economically recoverable groundwater when used for irrigation. The maximum economic depth is the maximum depth at which revenues are still larger than pumping costs or the maximum depth at which initial investments become too large compared to yearly revenues. To this end we set up a simple economic model where costs of well drilling and the energy costs of pumping, which are a function of well depth and static head depth respectively, are compared with the revenues obtained for the irrigated crops. Parameters for the cost sub-model are obtained from several US-based studies and applied to other countries based on GDP/capita as an index of labour costs. The revenue sub-model is based on gross irrigation water demand calculated with a global hydrological and water resources model, areal coverage of crop types from MIRCA2000 and FAO-based statistics on crop yield and market price. We applied our method to irrigated areas in the world overlying productive aquifers. Estimated maximum economic depths range between 50 and 500 m. Most important factors explaining the maximum economic depth are the dominant crop type in the area and whether or not initial investments in well infrastructure are limiting. In subsequent research, our estimates of

Topics in Bayesian statistics and maximum entropy

International Nuclear Information System (INIS)

Mutihac, R.; Cicuttin, A.; Cerdeira, A.; Stanciulescu, C.

1998-12-01

Notions of Bayesian decision theory and maximum entropy methods are reviewed with particular emphasis on probabilistic inference and Bayesian modeling. The axiomatic approach is considered as the best justification of Bayesian analysis and maximum entropy principle applied in natural sciences. Particular emphasis is put on solving the inverse problem in digital image restoration and Bayesian modeling of neural networks. Further topics addressed briefly include language modeling, neutron scattering, multiuser detection and channel equalization in digital communications, genetic information, and Bayesian court decision-making. (author)

The relationship between the parameters (Heart rate, Ejection fraction and BMI) and the maximum enhancement time of ascending aorta

International Nuclear Information System (INIS)

Jang, Young Ill; June, Woon Kwan; Dong, Kyeong Rae

2007-01-01

In this study, Bolus Tracking method was used to investigate the parameters affecting the time when contrast media is reached at 100 HU (T 100 ) and studied the relationship between parameters and T 100 because the time which is reached at aorta through antecubital vein after injecting contrast media is different from person to person. Using 64 MDCT, Cadiac CT, the data were obtained from 100 patients (male: 50, female: 50, age distribution: 21⁓81, average age: 57.5) during July and September, 2007 by injecting the contrast media at 4 ml∙sec -1 through their antecubital vein except having difficulties in stopping their breath and having arrhythmia. Using Somatom Sensation Cardiac 64 Siemens, patients’ height and weight were measured to know their mean Heart rate and BMI. Ejection Fraction was measured using Argus Program at Wizard Workstation. Variances of each parameter were analyzed depending on T 100 ’s variation with multiple comparison and the correlation of Heart rate, Ejection Fraction and BMI were analyzed, as well. According to T 100 ’s variation caused by Heart rate, Ejection Fraction and BMI variations, the higher patients’ Heart Rate and Ejection Fraction were, the faster T 100 ’s variations caused by Heart Rate and Ejection Fraction were. The lower their Heart Rate and Ejection Fraction were, the slower T 100 ’s variations were, but T 100 ’s variations caused by BMI were not affected. In the correlation between T 100 and parameters, Heart Rate (p⁄0.01) and Ejection Fraction (p⁄0.05) were significant, but BMI was not significant (p¤0.05). In the Heart Rate, Ejection Fraction and BMI depending on Fast (17 sec and less), Medium (18⁓21 sec), Slow (22 sec and over) Heart Rate was significant at Fast and Slow and Ejection Fraction was significant Fast and Slow as well as Medium and Slow (p⁄0.05), but BMI was not statistically significant. Of the parameters (Heart Rate, Ejection Fraction and BMI) which would affect T 100 , Heart

Maximum vehicle cabin temperatures under different meteorological conditions

Science.gov (United States)

Grundstein, Andrew; Meentemeyer, Vernon; Dowd, John

2009-05-01

A variety of studies have documented the dangerously high temperatures that may occur within the passenger compartment (cabin) of cars under clear sky conditions, even at relatively low ambient air temperatures. Our study, however, is the first to examine cabin temperatures under variable weather conditions. It uses a unique maximum vehicle cabin temperature dataset in conjunction with directly comparable ambient air temperature, solar radiation, and cloud cover data collected from April through August 2007 in Athens, GA. Maximum cabin temperatures, ranging from 41-76°C, varied considerably depending on the weather conditions and the time of year. Clear days had the highest cabin temperatures, with average values of 68°C in the summer and 61°C in the spring. Cloudy days in both the spring and summer were on average approximately 10°C cooler. Our findings indicate that even on cloudy days with lower ambient air temperatures, vehicle cabin temperatures may reach deadly levels. Additionally, two predictive models of maximum daily vehicle cabin temperatures were developed using commonly available meteorological data. One model uses maximum ambient air temperature and average daily solar radiation while the other uses cloud cover percentage as a surrogate for solar radiation. From these models, two maximum vehicle cabin temperature indices were developed to assess the level of danger. The models and indices may be useful for forecasting hazardous conditions, promoting public awareness, and to estimate past cabin temperatures for use in forensic analyses.

Combining Experiments and Simulations Using the Maximum Entropy Principle

DEFF Research Database (Denmark)

Boomsma, Wouter; Ferkinghoff-Borg, Jesper; Lindorff-Larsen, Kresten

2014-01-01

are not in quantitative agreement with experimental data. The principle of maximum entropy is a general procedure for constructing probability distributions in the light of new data, making it a natural tool in cases when an initial model provides results that are at odds with experiments. The number of maximum entropy...... in the context of a simple example, after which we proceed with a real-world application in the field of molecular simulations, where the maximum entropy procedure has recently provided new insight. Given the limited accuracy of force fields, macromolecular simulations sometimes produce results....... Three very recent papers have explored this problem using the maximum entropy approach, providing both new theoretical and practical insights to the problem. We highlight each of these contributions in turn and conclude with a discussion on remaining challenges....

Leaf Dynamics of Panicum maximum under Future Climatic Changes.

Science.gov (United States)

Britto de Assis Prado, Carlos Henrique; Haik Guedes de Camargo-Bortolin, Lívia; Castro, Érique; Martinez, Carlos Alberto

2016-01-01

Panicum maximum Jacq. 'Mombaça' (C4) was grown in field conditions with sufficient water and nutrients to examine the effects of warming and elevated CO2 concentrations during the winter. Plants were exposed to either the ambient temperature and regular atmospheric CO2 (Control); elevated CO2 (600 ppm, eC); canopy warming (+2°C above regular canopy temperature, eT); or elevated CO2 and canopy warming (eC+eT). The temperatures and CO2 in the field were controlled by temperature free-air controlled enhancement (T-FACE) and mini free-air CO2 enrichment (miniFACE) facilities. The most green, expanding, and expanded leaves and the highest leaf appearance rate (LAR, leaves day(-1)) and leaf elongation rate (LER, cm day(-1)) were observed under eT. Leaf area and leaf biomass were higher in the eT and eC+eT treatments. The higher LER and LAR without significant differences in the number of senescent leaves could explain why tillers had higher foliage area and leaf biomass in the eT treatment. The eC treatment had the lowest LER and the fewest expanded and green leaves, similar to Control. The inhibitory effect of eC on foliage development in winter was indicated by the fewer green, expanded, and expanding leaves under eC+eT than eT. The stimulatory and inhibitory effects of the eT and eC treatments, respectively, on foliage raised and lowered, respectively, the foliar nitrogen concentration. The inhibition of foliage by eC was confirmed by the eC treatment having the lowest leaf/stem biomass ratio and by the change in leaf biomass-area relationships from linear or exponential growth to rectangular hyperbolic growth under eC. Besides, eC+eT had a synergist effect, speeding up leaf maturation. Therefore, with sufficient water and nutrients in winter, the inhibitory effect of elevated CO2 on foliage could be partially offset by elevated temperatures and relatively high P. maximum foliage production could be achieved under future climatic change.

Novel maximum-margin training algorithms for supervised neural networks.

Science.gov (United States)

Ludwig, Oswaldo; Nunes, Urbano

2010-06-01

This paper proposes three novel training methods, two of them based on the backpropagation approach and a third one based on information theory for multilayer perceptron (MLP) binary classifiers. Both backpropagation methods are based on the maximal-margin (MM) principle. The first one, based on the gradient descent with adaptive learning rate algorithm (GDX) and named maximum-margin GDX (MMGDX), directly increases the margin of the MLP output-layer hyperplane. The proposed method jointly optimizes both MLP layers in a single process, backpropagating the gradient of an MM-based objective function, through the output and hidden layers, in order to create a hidden-layer space that enables a higher margin for the output-layer hyperplane, avoiding the testing of many arbitrary kernels, as occurs in case of support vector machine (SVM) training. The proposed MM-based objective function aims to stretch out the margin to its limit. An objective function based on Lp-norm is also proposed in order to take into account the idea of support vectors, however, overcoming the complexity involved in solving a constrained optimization problem, usually in SVM training. In fact, all the training methods proposed in this paper have time and space complexities O(N) while usual SVM training methods have time complexity O(N (3)) and space complexity O(N (2)) , where N is the training-data-set size. The second approach, named minimization of interclass interference (MICI), has an objective function inspired on the Fisher discriminant analysis. Such algorithm aims to create an MLP hidden output where the patterns have a desirable statistical distribution. In both training methods, the maximum area under ROC curve (AUC) is applied as stop criterion. The third approach offers a robust training framework able to take the best of each proposed training method. The main idea is to compose a neural model by using neurons extracted from three other neural networks, each one previously trained by

TRENDS IN ESTIMATED MIXING DEPTH DAILY MAXIMUMS

Energy Technology Data Exchange (ETDEWEB)

Buckley, R; Amy DuPont, A; Robert Kurzeja, R; Matt Parker, M

2007-11-12

Mixing depth is an important quantity in the determination of air pollution concentrations. Fireweather forecasts depend strongly on estimates of the mixing depth as a means of determining the altitude and dilution (ventilation rates) of smoke plumes. The Savannah River United States Forest Service (USFS) routinely conducts prescribed fires at the Savannah River Site (SRS), a heavily wooded Department of Energy (DOE) facility located in southwest South Carolina. For many years, the Savannah River National Laboratory (SRNL) has provided forecasts of weather conditions in support of the fire program, including an estimated mixing depth using potential temperature and turbulence change with height at a given location. This paper examines trends in the average estimated mixing depth daily maximum at the SRS over an extended period of time (4.75 years) derived from numerical atmospheric simulations using two versions of the Regional Atmospheric Modeling System (RAMS). This allows for differences to be seen between the model versions, as well as trends on a multi-year time frame. In addition, comparisons of predicted mixing depth for individual days in which special balloon soundings were released are also discussed.

Maximum entropy beam diagnostic tomography

International Nuclear Information System (INIS)

Mottershead, C.T.

1985-01-01

This paper reviews the formalism of maximum entropy beam diagnostic tomography as applied to the Fusion Materials Irradiation Test (FMIT) prototype accelerator. The same formalism has also been used with streak camera data to produce an ultrahigh speed movie of the beam profile of the Experimental Test Accelerator (ETA) at Livermore

Maximum-Likelihood Sequence Detection of Multiple Antenna Systems over Dispersive Channels via Sphere Decoding

Directory of Open Access Journals (Sweden)

Hassibi Babak

2002-01-01

Full Text Available Multiple antenna systems are capable of providing high data rate transmissions over wireless channels. When the channels are dispersive, the signal at each receive antenna is a combination of both the current and past symbols sent from all transmit antennas corrupted by noise. The optimal receiver is a maximum-likelihood sequence detector and is often considered to be practically infeasible due to high computational complexity (exponential in number of antennas and channel memory. Therefore, in practice, one often settles for a less complex suboptimal receiver structure, typically with an equalizer meant to suppress both the intersymbol and interuser interference, followed by the decoder. We propose a sphere decoding for the sequence detection in multiple antenna communication systems over dispersive channels. The sphere decoding provides the maximum-likelihood estimate with computational complexity comparable to the standard space-time decision-feedback equalizing (DFE algorithms. The performance and complexity of the sphere decoding are compared with the DFE algorithm by means of simulations.

A Maximum Radius for Habitable Planets.

Science.gov (United States)

Alibert, Yann

2015-09-01

We compute the maximum radius a planet can have in order to fulfill two constraints that are likely necessary conditions for habitability: 1- surface temperature and pressure compatible with the existence of liquid water, and 2- no ice layer at the bottom of a putative global ocean, that would prevent the operation of the geologic carbon cycle to operate. We demonstrate that, above a given radius, these two constraints cannot be met: in the Super-Earth mass range (1-12 Mearth), the overall maximum that a planet can have varies between 1.8 and 2.3 Rearth. This radius is reduced when considering planets with higher Fe/Si ratios, and taking into account irradiation effects on the structure of the gas envelope.

Case mix adjusted variation in cesarean section rate in Sweden.

Science.gov (United States)

Mesterton, Johan; Ladfors, Lars; Ekenberg Abreu, Anna; Lindgren, Peter; Saltvedt, Sissel; Weichselbraun, Marianne; Amer-Wåhlin, Isis

2017-05-01

Cesarean section (CS) rate is a well-established indicator of performance in maternity care and is also related to resource use. Case mix adjustment of CS rates when performing comparisons between hospitals is important. The objective of this study was to estimate case mix adjusted variation in CS rate between hospitals in Sweden. In total, 139 756 deliveries in 2011 and 2012 were identified in administrative systems in seven regions covering 67% of all deliveries in Sweden. Data were linked to the Medical birth register and population data. Twenty-three different sociodemographic and clinical characteristics were used for adjustment. Analyses were performed for the entire study population as well as for two subgroups. Logistic regression was used to analyze differences between hospitals. The overall CS rate was 16.9% (hospital minimum-maximum 12.1-22.6%). Significant variations in CS rate between hospitals were observed after case mix adjustment: hospital odds ratios for CS varied from 0.62 (95% CI 0.53-0.73) to 1.45 (95% CI 1.37-1.52). In nulliparous, cephalic, full-term, singletons the overall CS rate was 14.3% (hospital minimum-maximum: 9.0-19.0%), whereas it was 4.7% for multiparous, cephalic, full-term, singletons with no previous CS (hospital minimum-maximum: 3.2-6.7%). In both subgroups significant variations were observed in case mix adjusted CS rates. Significant differences in CS rate between Swedish hospitals were found after adjusting for differences in case mix. This indicates a potential for fewer interventions and lower resource use in Swedish childbirth care. Best practice sharing and continuous monitoring are important tools for improving childbirth care. © 2017 Nordic Federation of Societies of Obstetrics and Gynecology.

On semidefinite programming relaxations of maximum k-section

NARCIS (Netherlands)

de Klerk, E.; Pasechnik, D.V.; Sotirov, R.; Dobre, C.

2012-01-01

We derive a new semidefinite programming bound for the maximum k -section problem. For k=2 (i.e. for maximum bisection), the new bound is at least as strong as a well-known bound by Poljak and Rendl (SIAM J Optim 5(3):467–487, 1995). For k ≥ 3the new bound dominates a bound of Karisch and Rendl

Maximum Recoverable Gas from Hydrate Bearing Sediments by Depressurization

KAUST Repository

Terzariol, Marco

2017-11-13

The estimation of gas production rates from hydrate bearing sediments requires complex numerical simulations. This manuscript presents a set of simple and robust analytical solutions to estimate the maximum depressurization-driven recoverable gas. These limiting-equilibrium solutions are established when the dissociation front reaches steady state conditions and ceases to expand further. Analytical solutions show the relevance of (1) relative permeabilities between the hydrate free sediment, the hydrate bearing sediment, and the aquitard layers, and (2) the extent of depressurization in terms of the fluid pressures at the well, at the phase boundary, and in the far field. Close form solutions for the size of the produced zone allow for expeditious financial analyses; results highlight the need for innovative production strategies in order to make hydrate accumulations an economically-viable energy resource. Horizontal directional drilling and multi-wellpoint seafloor dewatering installations may lead to advantageous production strategies in shallow seafloor reservoirs.

Modeling multisite streamflow dependence with maximum entropy copula

Science.gov (United States)

Hao, Z.; Singh, V. P.

2013-10-01

Synthetic streamflows at different sites in a river basin are needed for planning, operation, and management of water resources projects. Modeling the temporal and spatial dependence structure of monthly streamflow at different sites is generally required. In this study, the maximum entropy copula method is proposed for multisite monthly streamflow simulation, in which the temporal and spatial dependence structure is imposed as constraints to derive the maximum entropy copula. The monthly streamflows at different sites are then generated by sampling from the conditional distribution. A case study for the generation of monthly streamflow at three sites in the Colorado River basin illustrates the application of the proposed method. Simulated streamflow from the maximum entropy copula is in satisfactory agreement with observed streamflow.

Distribution of photon absorption rates across the rat retina.

Science.gov (United States)

Williams, T P; Webbers, J P; Giordano, L; Henderson, R P

1998-04-15

1. An investigation into the distribution of light intensity across the rat retina was carried out on excised, intact rat eyes exposed to Ganzfeld illumination from a helium-neon laser (543 nm). 2. Some of the light entering the eyes exits through the sclera where its intensity can be monitored with an optical 'pick-up' that samples the intensity coming from a small region of external sclera and underlying retina. The spatial resolution of the pick-up is such that it samples light that has passed through ca 2 % of the rods in the rat eye. 3. Some of the laser light is absorbed by the rod pigment, rhodopsin, which gradually bleaches. Bleaching in the retina, in turn, causes an exponential increase in intensity emanating from the sclera. By monitoring this intensity increase, we are able to measure two important parameters in a single bleaching run: the local rhodopsin concentration and the local intensity falling on the rods. 4. With an ocular transmission photometer, we have measured both the local intensity and the local rhodopsin concentration across wide regions of rat retina. Both pigmented and albino rats were studied. 5. The distributions of rhodopsin and intensity were both nearly uniform; consequently, the product, (rhodopsin concentration) x (intensity), was similarly nearly equal across the retina. This means that the initial rate of photon absorption is about the same at all retinal locations. 6. Interpreted in terms of photostasis (the regulation of daily photon catch), this means that the rate of photon absorption is about the same in each rod, viz. 14 400 photons absorbed per rod per second. Since this rate of absorption is sufficient to saturate the rod, one possible purpose of photostasis is to maintain the rod system in a saturated state during daylight hours.

Maximum stellar iron core mass

Indian Academy of Sciences (India)

60, No. 3. — journal of. March 2003 physics pp. 415–422. Maximum stellar iron core mass. F W GIACOBBE. Chicago Research Center/American Air Liquide ... iron core compression due to the weight of non-ferrous matter overlying the iron cores within large .... thermal equilibrium velocities will tend to be non-relativistic.

An iterative procedure for obtaining maximum-likelihood estimates of the parameters for a mixture of normal distributions, 2

Science.gov (United States)

Peters, B. C., Jr.; Walker, H. F.

1976-01-01

The problem of obtaining numerically maximum likelihood estimates of the parameters for a mixture of normal distributions is addressed. In recent literature, a certain successive approximations procedure, based on the likelihood equations, is shown empirically to be effective in numerically approximating such maximum-likelihood estimates; however, the reliability of this procedure was not established theoretically. Here, a general iterative procedure is introduced, of the generalized steepest-ascent (deflected-gradient) type, which is just the procedure known in the literature when the step-size is taken to be 1. With probability 1 as the sample size grows large, it is shown that this procedure converges locally to the strongly consistent maximum-likelihood estimate whenever the step-size lies between 0 and 2. The step-size which yields optimal local convergence rates for large samples is determined in a sense by the separation of the component normal densities and is bounded below by a number between 1 and 2.

The maximum and minimum values of the heat Q transmitted from metal to boiling water under atmospheric pressure

International Nuclear Information System (INIS)

Nukiyama, S.

1991-01-01

The quantity of heat transmitted from a metal surface to boiling water increases as the temperature difference ΔT is increased, but after the ΔT has reached a certain limit, quantity Q decreases with further increase in ΔT. This turning point is the maximum value of heat transmitted. The existence of this point was actually observed in the experiment. Under atmospheric pressure, ΔT corresponding to the maximum value of heat transfer for water at 100 degrees C falls between 20-40 degrees C, and Q is between 1,080,000 and 1,800,000 kcal/m 2 h (i.e. between 2,000 and 3,000 kg/m 2 h, if expressed in constant evaporation rate at 100 degrees C); this figure is larger than the maximum value of heat transfer as was previously considered. In this paper the minimum value of heat transfer was obtained, and in the Q-ΔT curve for the high temperature region, the burn-out effect is discussed

The regulation of starch accumulation in Panicum maximum Jacq ...

African Journals Online (AJOL)

... decrease the starch level. These observations are discussed in relation to the photosynthetic characteristics of P. maximum. Keywords: accumulation; botany; carbon assimilation; co2 fixation; growth conditions; mesophyll; metabolites; nitrogen; nitrogen levels; nitrogen supply; panicum maximum; plant physiology; starch; ...

Effect of background music on maximum acceptable weight of manual lifting tasks.

Science.gov (United States)

Yu, Ruifeng

2014-01-01

This study used the psychophysical approach to investigate the impact of tempo and volume of background music on the maximum acceptable weight of lift (MAWL), heart rate (HR) and rating of perceived exertion (RPE) of participants engaged in lifting. Ten male college students participated in this study. They lifted a box from the floor, walked 1-2 steps as required, placed the box on a table and walked back twice per minute. The results showed that the tempo of music had a significant effect on both MAWL and HR. Fast tempo background music resulted in higher MAWL and HR values than those resulting from slow tempo music. The effects of both the tempo and volume on the RPE were insignificant. The results of this study suggest fast tempo background music may be used in manual materials handling tasks to increase performance without increasing perceived exertion because of its ergogenic effect on human psychology and physiology.

Leak rate test of containment personnel lock

International Nuclear Information System (INIS)

Julien, J.T.; Peters, S.W.

1988-01-01

As part of the US NRC Containment Integrity Program, a leak rate test was performed on a full size personnel airlock for a nuclear containment building. The airlock was subjected to conditions simulating severe accident conditions. The objective of the test was to characterize the performance of airlock door seals when subjected to conditions that exceeded design. The seals tested were a double dog-ear configuration and made from EPDM E603. The data obtained from this test will be used by SNL as a benchmark for development of analytical methods. In addition to leak rate information, strain, temperature, displacements, and pressure data were measured and recorded from over 330 transducers. The test lasted approximately 60 hours. Data were recorded at regular intervals and during heating, pressurization and depressurization. The inner airlock door and bulkhead were exposed to a maximum air temperature of 850 F and a maximum air pressure of 300 psig. The airlock was originally designed for 340 F and 60 psig. Two heating and pressurization cycles were planned; one to heat to 400 F and pressurize to 300 psig, and the second to heat to 800 F and pressurize to 300 psig. No significant leakage was recorded during these two cycles. A third cycle was added to the test program. The air temperature was increased to 850 F and held at this temperature for approximately 10 hours. The inner door seal failed quickly at a pressure of 150.5 psig. The maximum leak rate was 706 SCFM

Maximum entropy beam diagnostic tomography

International Nuclear Information System (INIS)

Mottershead, C.T.

1985-01-01

This paper reviews the formalism of maximum entropy beam diagnostic tomography as applied to the Fusion Materials Irradiation Test (FMIT) prototype accelerator. The same formalism has also been used with streak camera data to produce an ultrahigh speed movie of the beam profile of the Experimental Test Accelerator (ETA) at Livermore. 11 refs., 4 figs

A portable storage maximum thermometer

International Nuclear Information System (INIS)

Fayart, Gerard.

1976-01-01

A clinical thermometer storing the voltage corresponding to the maximum temperature in an analog memory is described. End of the measurement is shown by a lamp switch out. The measurement time is shortened by means of a low thermal inertia platinum probe. This portable thermometer is fitted with cell test and calibration system [fr

A Maximum Resonant Set of Polyomino Graphs

Directory of Open Access Journals (Sweden)

Zhang Heping

2016-05-01

Full Text Available A polyomino graph P is a connected finite subgraph of the infinite plane grid such that each finite face is surrounded by a regular square of side length one and each edge belongs to at least one square. A dimer covering of P corresponds to a perfect matching. Different dimer coverings can interact via an alternating cycle (or square with respect to them. A set of disjoint squares of P is a resonant set if P has a perfect matching M so that each one of those squares is M-alternating. In this paper, we show that if K is a maximum resonant set of P, then P − K has a unique perfect matching. We further prove that the maximum forcing number of a polyomino graph is equal to the cardinality of a maximum resonant set. This confirms a conjecture of Xu et al. [26]. We also show that if K is a maximal alternating set of P, then P − K has a unique perfect matching.

Spatio-temporal observations of the tertiary ozone maximum

Directory of Open Access Journals (Sweden)

V. F. Sofieva

2009-07-01

Full Text Available We present spatio-temporal distributions of the tertiary ozone maximum (TOM, based on GOMOS (Global Ozone Monitoring by Occultation of Stars ozone measurements in 2002–2006. The tertiary ozone maximum is typically observed in the high-latitude winter mesosphere at an altitude of ~72 km. Although the explanation for this phenomenon has been found recently – low concentrations of odd-hydrogen cause the subsequent decrease in odd-oxygen losses – models have had significant deviations from existing observations until recently. Good coverage of polar night regions by GOMOS data has allowed for the first time to obtain spatial and temporal observational distributions of night-time ozone mixing ratio in the mesosphere.

The distributions obtained from GOMOS data have specific features, which are variable from year to year. In particular, due to a long lifetime of ozone in polar night conditions, the downward transport of polar air by the meridional circulation is clearly observed in the tertiary ozone maximum time series. Although the maximum tertiary ozone mixing ratio is achieved close to the polar night terminator (as predicted by the theory, TOM can be observed also at very high latitudes, not only in the beginning and at the end, but also in the middle of winter. We have compared the observational spatio-temporal distributions of the tertiary ozone maximum with that obtained using WACCM (Whole Atmosphere Community Climate Model and found that the specific features are reproduced satisfactorily by the model.

Since ozone in the mesosphere is very sensitive to HO_x concentrations, energetic particle precipitation can significantly modify the shape of the ozone profiles. In particular, GOMOS observations have shown that the tertiary ozone maximum was temporarily destroyed during the January 2005 and December 2006 solar proton events as a result of the HO_x enhancement from the increased ionization.

Is There a Maximum Star Formation Rate in High-redshift Galaxies?

Science.gov (United States)

Barger, A. J.; Cowie, L. L.; Chen, C.-C.; Owen, F. N.; Wang, W.-H.; Casey, C. M.; Lee, N.; Sanders, D. B.; Williams, J. P.

2014-03-01

We use the James Clerk Maxwell Telescope's SCUBA-2 camera to image a 400 arcmin2 area surrounding the GOODS-N field. The 850 μm rms noise ranges from a value of 0.49 mJy in the central region to 3.5 mJy at the outside edge. From these data, we construct an 850 μm source catalog to 2 mJy containing 49 sources detected above the 4σ level. We use an ultradeep (11.5 μJy at 5σ) 1.4 GHz image obtained with the Karl G. Jansky Very Large Array together with observations made with the Submillimeter Array to identify counterparts to the submillimeter galaxies. For most cases of multiple radio counterparts, we can identify the correct counterpart from new and existing Submillimeter Array data. We have spectroscopic redshifts for 62% of the radio sources in the 9' radius highest sensitivity region (556/894) and 67% of the radio sources in the GOODS-N region (367/543). We supplement these with a modest number of additional photometric redshifts in the GOODS-N region (30). We measure millimetric redshifts from the radio to submillimeter flux ratios for the unidentified submillimeter sample, assuming an Arp 220 spectral energy distribution. We find a radio-flux-dependent K - z relation for the radio sources, which we use to estimate redshifts for the remaining radio sources. We determine the star formation rates (SFRs) of the submillimeter sources based on their radio powers and their submillimeter fluxes and find that they agree well. The radio data are deep enough to detect star-forming galaxies with SFRs >2000 M ⊙ yr-1 to z ~ 6. We find galaxies with SFRs up to ~6000 M ⊙ yr-1 over the redshift range z = 1.5-6, but we see evidence for a turn-down in the SFR distribution function above 2000 M ⊙ yr-1. The James Clerk Maxwell Telescope is operated by the Joint Astronomy Centre on behalf of the Science and Technology Facilities Council of the United Kingdom, the National Research Council of Canada, and (until 2013 March 31) the Netherlands Organisation for Scientific

A new method for the determination of radium-228, thorium-228, and radium-224 in groundwaters via thoron (radon-220)

International Nuclear Information System (INIS)

Smith, M.R.; Lautensleger, A.W.; Laul, J.C.

1988-01-01

An improved method for determining radium and thorium from the 232 Th decay series has been developed which measures the activity of 220 Rn as an assay of its parents. Although some ingrowth corrections and minor separation procedures for Th are required, the results to date show that the dynamic counting of 220 Rn via de-emanation and alpha counting by the alpha-scintillation method is preferable. The method for lower limit detection depends on the emanation rate. (author) 3 refs.; 6 figs

Association of heart rate profile during exercise with the severity of coronary artery disease.

Science.gov (United States)

Cay, Serkan; Ozturk, Sezgin; Biyikoglu, Funda; Yildiz, Abdulkadir; Cimen, Tolga; Uygur, Belma; Tuna, Funda

2009-05-01

Coronary artery disease is the leading cause of morbidity and mortality around the world. Autonomic nervous system abnormalities are associated with coronary artery disease and its complications. Exercise stress tests are routinely used for the detection of the presence of coronary artery disease. In this study, we observed the association between heart rate profile during exercise and the severity of coronary artery disease. One hundred and sixty patients with abnormal exercise treadmill test (> or =1 mm horizontal or downsloping ST-segment depression; 119 men, 41 women; mean age = 57 +/- 9 years) were included in the study. Use of any drug affecting heart rate was not permitted. Resting heart rate before exercise, maximum heart rate during exercise, and resting heart rate after exercise (5 min later) were measured and two parameters were calculated: heart rate increment (maximum heart rate - resting heart rate before exercise) and heart rate decrement (maximum heart rate - resting heart rate after exercise). All patients underwent selective coronary angiography and subclassified into two groups according to stenotic lesion severity. Group 1 had at least 50% of stenotic lesion and group 2 had less than 50%. Patients in the first group had increased resting heart rate, decreased maximum heart rate, decreased heart rate increment, and decreased heart rate decrement compared with second group. All patients were classified into tertiles of resting heart rate, heart rate increment, and heart rate decrement level to evaluate whether these parameters were associated with severity of coronary artery stenosis in the study. The multiple-adjusted odds ratio of the risk of severe coronary atherosclerosis was 21.888 (95% confidence interval 6.983-68.606) for the highest tertile of resting heart rate level compared with the lowest tertile. In addition, the multiple-adjusted odds ratio of the risk of severe coronary atherosclerosis was 20.987 (95% confidence interval 6

A maximum pseudo-likelihood approach for estimating species trees under the coalescent model

Directory of Open Access Journals (Sweden)

Edwards Scott V

2010-10-01

Full Text Available Abstract Background Several phylogenetic approaches have been developed to estimate species trees from collections of gene trees. However, maximum likelihood approaches for estimating species trees under the coalescent model are limited. Although the likelihood of a species tree under the multispecies coalescent model has already been derived by Rannala and Yang, it can be shown that the maximum likelihood estimate (MLE of the species tree (topology, branch lengths, and population sizes from gene trees under this formula does not exist. In this paper, we develop a pseudo-likelihood function of the species tree to obtain maximum pseudo-likelihood estimates (MPE of species trees, with branch lengths of the species tree in coalescent units. Results We show that the MPE of the species tree is statistically consistent as the number M of genes goes to infinity. In addition, the probability that the MPE of the species tree matches the true species tree converges to 1 at rate O(M -1. The simulation results confirm that the maximum pseudo-likelihood approach is statistically consistent even when the species tree is in the anomaly zone. We applied our method, Maximum Pseudo-likelihood for Estimating Species Trees (MP-EST to a mammal dataset. The four major clades found in the MP-EST tree are consistent with those in the Bayesian concatenation tree. The bootstrap supports for the species tree estimated by the MP-EST method are more reasonable than the posterior probability supports given by the Bayesian concatenation method in reflecting the level of uncertainty in gene trees and controversies over the relationship of four major groups of placental mammals. Conclusions MP-EST can consistently estimate the topology and branch lengths (in coalescent units of the species tree. Although the pseudo-likelihood is derived from coalescent theory, and assumes no gene flow or horizontal gene transfer (HGT, the MP-EST method is robust to a small amount of HGT in the

Direct maximum parsimony phylogeny reconstruction from genotype data

OpenAIRE

Sridhar, Srinath; Lam, Fumei; Blelloch, Guy E; Ravi, R; Schwartz, Russell

2007-01-01

Abstract Background Maximum parsimony phylogenetic tree reconstruction from genetic variation data is a fundamental problem in computational genetics with many practical applications in population genetics, whole genome analysis, and the search for genetic predictors of disease. Efficient methods are available for reconstruction of maximum parsimony trees from haplotype data, but such data are difficult to determine directly for autosomal DNA. Data more commonly is available in the form of ge...

Rates and limits of climatic change: Discussion of possible targets; Rates and limits of temperature, precipitation, and sea-level changes

Energy Technology Data Exchange (ETDEWEB)

Gleick, P H [Pacific Inst. for SiDES, Berkeley, CA (US); Sassin, W [Landl (AT)

1990-10-01

The rate of sea-level rise over the next century is likely to accelerate rapidly and exceed rates of rise experienced over the last several thousand years. Under these conditions, adverse effects on natural ecosystems such as coastal marshes and coral reef islands would be widely observable by 2050, and would be noticeable in vulnerable ecosystems by the year 2000, even under low sea-level rise scenario. Non-linearities and sudden events such as storm surges and a change in storm frequency and intensity could lead to damages even earlier. Similarly, change in temperature and precipitation patterns far greater than those experienced in the last 10000to 100000 years seem likely unless strong actions are taken soon. Rates of change in temperature, precipitation, and sea level over geologic time have often exceeded the rates expected over the next century from global warming. These large excursions, however, were often accompanied by dramatic changes in ecosystems and by large species extinctions, and they occurred when no human infrastructure existed. The adaptive abilities of natural ecosystems can be used to define targets of maximum rates of rise. For coral reef islands and coastal marshes, the maximum rate of accretion of materials is 10 to 15 mm/yr. At this rate, however, many reefs and marshes that accrete materials at slower rates will be inundated and destroyed. Average rates of accretion for marshes are lower - between 2 and 5 mm/yr, and between 5 and 10 mm/yr for coral reefs. Even at these lower rates, some ecosystem losses are to be expected. This information leads to a recommended target for the rate of sea-level rise of between 20 and 50 mm per decade, and a target for absolute sea-level rise of between 0.2 and 0.5 above the 1990 global mean sea level. (authors).

Implantation rate effects on microstructure

International Nuclear Information System (INIS)

Choyke, W.J.; Spitznagel, J.A.; Wood, S.; Doyle, N.J.

1981-01-01

We report a detailed TEM study of rate effects in a metal (304 SS) where we dope with an insoluble atom (He) and create the displacement damage with high energy Si. The rates of doping and the rates of producing lattice damage are independently varied during dual implantation. In addition to varying the doping rates of the He the magnitude of the displacement damage prior to He implantation is also varied (beam history). We find that the beam history has virtually no effect on maximum bubble size but it has a major effect on the average cavity diameter. A weak dependence of cavity number density on helium implantation rate is found. The total dislocation density is relatively independent of the doping rate and beam history at 550 and 700 0 C, whereas the loop fraction is sensitive to beam history at these temperatures. Acicular precipitate formation is weakly dependent on doping, doping rate and more strongly dependent on doping concentration and temperature. This form of solute segregation is very sensitive to beam history. (orig.)

Fungic microflora of Panicum maximum and Styosanthes spp. commercial seed / Microflora fúngica de sementes comerciais de Panicum maximum e Stylosanthes spp.

Directory of Open Access Journals (Sweden)

Larissa Rodrigues Fabris

2010-09-01

Full Text Available The sanitary quality of 26 lots commercial seeds of tropical forages, produced in different regions (2004-05 and 2005-06 was analyzed. The lots were composed of seeds of Panicum maximum ('Massai', 'Mombaça' e 'Tanzânia' and stylo ('Estilosantes Campo Grande' - ECG. Additionally, seeds of two lots of P. maximum for exportation were analyzed. The blotter test was used, at 20ºC under alternating light and darkness in a 12 h photoperiod, for seven days. The Aspergillus, Cladosporium and Rhizopus genus consisted the secondary or saprophytes fungi (FSS with greatest frequency in P. maximum lots. In general, there was low incidence of these fungus in the seeds. In relation to pathogenic fungi (FP, it was detected high frequency of contaminated lots by Bipolaris, Curvularia, Fusarium and Phoma genus. Generally, there was high incidence of FP in P. maximum seeds. The occurrence of Phoma sp. was hight, because in 81% of the lots showed incidence superior to 50%. In 'ECG' seeds it was detected FSS (Aspergillus, Cladosporium, and Penicillium genus and FP (Bipolaris, Curvularia, Fusarium and Phoma genus, usually, in low incidence. FSS and FP were associated to P. maximum seeds for exportation, with significant incidence in some cases. The results indicated that there was a limiting factor in all producer regions regarding sanitary quality of the seeds.Sementes comerciais de forrageiras tropicais, pertencente a 26 lotes produzidos em diferentes regiões (safras 2004-05 e 2005-06, foram avaliadas quanto à sanidade. Foram analisadas sementes de cultivares de Panicum maximum (Massai, Mombaça e Tanzânia e de estilosantes (Estilosantes Campo Grande – ECG. Adicionalmente, avaliou-se a qualidade sanitária de dois lotes de sementes de P. maximum destinados à exportação. Para isso, as sementes foram submetidas ao teste de papel de filtro em gerbox, os quais foram incubados a 20ºC, com fotoperíodo de 12 h, durante sete dias. Os fungos saprófitos ou

78 FR 49370 - Inflation Adjustment of Maximum Forfeiture Penalties

Science.gov (United States)

2013-08-14

... ``civil monetary penalties provided by law'' at least once every four years. DATES: Effective September 13... increases the maximum civil monetary forfeiture penalties available to the Commission under its rules... maximum civil penalties established in that section to account for inflation since the last adjustment to...

5 CFR 838.711 - Maximum former spouse survivor annuity.

Science.gov (United States)

2010-01-01

... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Maximum former spouse survivor annuity... Orders Awarding Former Spouse Survivor Annuities Limitations on Survivor Annuities § 838.711 Maximum former spouse survivor annuity. (a) Under CSRS, payments under a court order may not exceed the amount...

Cross-layer optimized rate adaptation and scheduling for multiple-user wireless video streaming

NARCIS (Netherlands)

Ozcelebi, T.; Sunay, M.O.; Tekalp, A.M.; Civanlar, M.R.

2007-01-01

We present a cross-layer optimized video rate adaptation and user scheduling scheme for multi-user wireless video streaming aiming for maximum quality of service (QoS) for each user,, maximum system video throughput, and QoS fairness among users. These objectives are jointly optimized using a

A tropospheric ozone maximum over the equatorial Southern Indian Ocean

Directory of Open Access Journals (Sweden)

L. Zhang

2012-05-01

Full Text Available We examine the distribution of tropical tropospheric ozone (O₃ from the Microwave Limb Sounder (MLS and the Tropospheric Emission Spectrometer (TES by using a global three-dimensional model of tropospheric chemistry (GEOS-Chem. MLS and TES observations of tropospheric O₃ during 2005 to 2009 reveal a distinct, persistent O₃ maximum, both in mixing ratio and tropospheric column, in May over the Equatorial Southern Indian Ocean (ESIO. The maximum is most pronounced in 2006 and 2008 and less evident in the other three years. This feature is also consistent with the total column O₃ observations from the Ozone Mapping Instrument (OMI and the Atmospheric Infrared Sounder (AIRS. Model results reproduce the observed May O₃ maximum and the associated interannual variability. The origin of the maximum reflects a complex interplay of chemical and dynamic factors. The O₃ maximum is dominated by the O₃ production driven by lightning nitrogen oxides (NO_x emissions, which accounts for 62% of the tropospheric column O₃ in May 2006. We find the contribution from biomass burning, soil, anthropogenic and biogenic sources to the O₃ maximum are rather small. The O₃ productions in the lightning outflow from Central Africa and South America both peak in May and are directly responsible for the O₃ maximum over the western ESIO. The lightning outflow from Equatorial Asia dominates over the eastern ESIO. The interannual variability of the O₃ maximum is driven largely by the anomalous anti-cyclones over the southern Indian Ocean in May 2006 and 2008. The lightning outflow from Central Africa and South America is effectively entrained by the anti-cyclones followed by northward transport to the ESIO.

Solar maximum observatory

International Nuclear Information System (INIS)

Rust, D.M.

1984-01-01

The successful retrieval and repair of the Solar Maximum Mission (SMM) satellite by Shuttle astronauts in April 1984 permitted continuance of solar flare observations that began in 1980. The SMM carries a soft X ray polychromator, gamma ray, UV and hard X ray imaging spectrometers, a coronagraph/polarimeter and particle counters. The data gathered thus far indicated that electrical potentials of 25 MeV develop in flares within 2 sec of onset. X ray data show that flares are composed of compressed magnetic loops that have come too close together. Other data have been taken on mass ejection, impacts of electron beams and conduction fronts with the chromosphere and changes in the solar radiant flux due to sunspots. 13 references

Post optimization paradigm in maximum 3-satisfiability logic programming

Science.gov (United States)

Mansor, Mohd. Asyraf; Sathasivam, Saratha; Kasihmuddin, Mohd Shareduwan Mohd

2017-08-01

Maximum 3-Satisfiability (MAX-3SAT) is a counterpart of the Boolean satisfiability problem that can be treated as a constraint optimization problem. It deals with a conundrum of searching the maximum number of satisfied clauses in a particular 3-SAT formula. This paper presents the implementation of enhanced Hopfield network in hastening the Maximum 3-Satisfiability (MAX-3SAT) logic programming. Four post optimization techniques are investigated, including the Elliot symmetric activation function, Gaussian activation function, Wavelet activation function and Hyperbolic tangent activation function. The performances of these post optimization techniques in accelerating MAX-3SAT logic programming will be discussed in terms of the ratio of maximum satisfied clauses, Hamming distance and the computation time. Dev-C++ was used as the platform for training, testing and validating our proposed techniques. The results depict the Hyperbolic tangent activation function and Elliot symmetric activation function can be used in doing MAX-3SAT logic programming.

9 CFR 381.67 - Young chicken and squab slaughter inspection rate maximums under traditional inspection procedure.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Young chicken and squab slaughter... INSPECTION REGULATIONS Operating Procedures § 381.67 Young chicken and squab slaughter inspection rate... inspector per minute under the traditional inspection procedure for the different young chicken and squab...

Mass mortality of the vermetid gastropod Ceraesignum maximum

Science.gov (United States)

Brown, A. L.; Frazer, T. K.; Shima, J. S.; Osenberg, C. W.

2016-09-01

Ceraesignum maximum (G.B. Sowerby I, 1825), formerly Dendropoma maximum, was subject to a sudden, massive die-off in the Society Islands, French Polynesia, in 2015. On Mo'orea, where we have detailed documentation of the die-off, these gastropods were previously found in densities up to 165 m-2. In July 2015, we surveyed shallow back reefs of Mo'orea before, during and after the die-off, documenting their swift decline. All censused populations incurred 100% mortality. Additional surveys and observations from Mo'orea, Tahiti, Bora Bora, and Huahine (but not Taha'a) suggested a similar, and approximately simultaneous, die-off. The cause(s) of this cataclysmic mass mortality are currently unknown. Given the previously documented negative effects of C. maximum on corals, we expect the die-off will have cascading effects on the reef community.

Statistic method of research reactors maximum permissible power calculation

International Nuclear Information System (INIS)

Grosheva, N.A.; Kirsanov, G.A.; Konoplev, K.A.; Chmshkyan, D.V.

1998-01-01

The technique for calculating maximum permissible power of a research reactor at which the probability of the thermal-process accident does not exceed the specified value, is presented. The statistical method is used for the calculations. It is regarded that the determining function related to the reactor safety is the known function of the reactor power and many statistically independent values which list includes the reactor process parameters, geometrical characteristics of the reactor core and fuel elements, as well as random factors connected with the reactor specific features. Heat flux density or temperature is taken as a limiting factor. The program realization of the method discussed is briefly described. The results of calculating the PIK reactor margin coefficients for different probabilities of the thermal-process accident are considered as an example. It is shown that the probability of an accident with fuel element melting in hot zone is lower than 10 -8 1 per year for the reactor rated power [ru

Multifield stochastic particle production: beyond a maximum entropy ansatz

Energy Technology Data Exchange (ETDEWEB)

Amin, Mustafa A.; Garcia, Marcos A.G.; Xie, Hong-Yi; Wen, Osmond, E-mail: mustafa.a.amin@gmail.com, E-mail: marcos.garcia@rice.edu, E-mail: hxie39@wisc.edu, E-mail: ow4@rice.edu [Physics and Astronomy Department, Rice University, 6100 Main Street, Houston, TX 77005 (United States)

2017-09-01

We explore non-adiabatic particle production for N {sub f} coupled scalar fields in a time-dependent background with stochastically varying effective masses, cross-couplings and intervals between interactions. Under the assumption of weak scattering per interaction, we provide a framework for calculating the typical particle production rates after a large number of interactions. After setting up the framework, for analytic tractability, we consider interactions (effective masses and cross couplings) characterized by series of Dirac-delta functions in time with amplitudes and locations drawn from different distributions. Without assuming that the fields are statistically equivalent, we present closed form results (up to quadratures) for the asymptotic particle production rates for the N {sub f}=1 and N {sub f}=2 cases. We also present results for the general N {sub f} >2 case, but with more restrictive assumptions. We find agreement between our analytic results and direct numerical calculations of the total occupation number of the produced particles, with departures that can be explained in terms of violation of our assumptions. We elucidate the precise connection between the maximum entropy ansatz (MEA) used in Amin and Baumann (2015) and the underlying statistical distribution of the self and cross couplings. We provide and justify a simple to use (MEA-inspired) expression for the particle production rate, which agrees with our more detailed treatment when the parameters characterizing the effective mass and cross-couplings between fields are all comparable to each other. However, deviations are seen when some parameters differ significantly from others. We show that such deviations become negligible for a broad range of parameters when N {sub f}>> 1.

Intelligent approach to maximum power point tracking control strategy for variable-speed wind turbine generation system

Energy Technology Data Exchange (ETDEWEB)

Lin, Whei-Min; Hong, Chih-Ming [Department of Electrical Engineering, National Sun Yat-Sen University, Kaohsiung 80424 (China)

2010-06-15

To achieve maximum power point tracking (MPPT) for wind power generation systems, the rotational speed of wind turbines should be adjusted in real time according to wind speed. In this paper, a Wilcoxon radial basis function network (WRBFN) with hill-climb searching (HCS) MPPT strategy is proposed for a permanent magnet synchronous generator (PMSG) with a variable-speed wind turbine. A high-performance online training WRBFN using a back-propagation learning algorithm with modified particle swarm optimization (MPSO) regulating controller is designed for a PMSG. The MPSO is adopted in this study to adapt to the learning rates in the back-propagation process of the WRBFN to improve the learning capability. The MPPT strategy locates the system operation points along the maximum power curves based on the dc-link voltage of the inverter, thus avoiding the generator speed detection. (author)

Maximum power point tracking controller for PV systems using neural networks

Energy Technology Data Exchange (ETDEWEB)

Bahgat, A.B.G. [Cairo Univ. (Egypt). Faculty of Engineering; Helwa, N.H.; Ahmad, G.E.; El Shenawy, E.T. [National Research Center, Dokki, Cairo (Egypt). Solar Energy Dept.

2005-07-01

This paper presents a development and implementation of a PC-based maximum power point tracker (MPPT) for PV system using neural networks (NN). The system consists of a PV module via a MPPT supplying a dc motor that drives an air fan. The control algorithm is developed to use the artificial NN for detecting the optimal operating point under different operating conditions, then the control action gives the driving signals to the MPPT. A PC is used for data acquisition, running the control algorithm, data storage, as well as data display and analysis. The system has been implemented and tested under various operating conditions. The experimental results showed that the PV system with MPPT always tracks the peak power point of the PV module under various operating conditions. The MPPT transmits about 97% of the actual maximum power generated by the PV module. The MPPT not only increases the power from the PV module to the load, but also maintains longer operating periods for the PV system. The air velocity and the air mass flow rate of the mechanical load are increased considerably, due to the increase of the PV system power. It is also found that the increase in the output energy due to using the MPPT is about 45.2% for a clear sunny day. (Author)

Maximum phytoplankton concentrations in the sea

DEFF Research Database (Denmark)

Jackson, G.A.; Kiørboe, Thomas

2008-01-01

A simplification of plankton dynamics using coagulation theory provides predictions of the maximum algal concentration sustainable in aquatic systems. These predictions have previously been tested successfully against results from iron fertilization experiments. We extend the test to data collect...

Rate enhancement in microfabricated chemical reactors under fast forced temperature oscillations

DEFF Research Database (Denmark)

Hansen, Heine Anton; Olsen, Jakob L.; Jensen, Søren

2006-01-01

Oxidation of CO under fast forced temperature oscillations shows increased reaction rate compared to steady state. A maximum increase of 40% is observed relative to steady state. The reaction rate is investigated for varying mean temperature, amplitude and frequency. As function of mean temperatu...

On the Pontryagin maximum principle for systems with delays. Economic applications

Science.gov (United States)

Kim, A. V.; Kormyshev, V. M.; Kwon, O. B.; Mukhametshin, E. R.

2017-11-01

The Pontryagin maximum principle [6] is the key stone of finite-dimensional optimal control theory [1, 2, 5]. So beginning with opening the maximum principle it was important to extend the maximum principle on various classes of dynamical systems. In t he paper we consider some aspects of application of i-smooth analysis [3, 4] in the theory of the Pontryagin maximum principle [6] for systems with delays, obtained results can be applied by elaborating optimal program controls in economic models with delays.

Efficient high-peak-power and high-repetition-rate eye-safe laser using an intracavity KTP OPO

International Nuclear Information System (INIS)

Guo, J; Jiao, Z X; Wang, B; He, G Y

2015-01-01

An efficient high-peak-power and high-repetition-rate intracavity KTP optical parametric oscillator pumped by a Q-switched Nd:YVO 4 laser is demonstrated. We achieved 1.5 W output power of 1.5 μm at 10 kHz repetition rate with the pulse duration of 6 ns. The maximum peak power of 25 kW and the maximum pulse energy of 150 μJ have been obtained. The maximum conversion efficiency of 9.5% is achieved with respect to a laser diode power of 10.5 W. (paper)

MAXIMUM CORONAL MASS EJECTION SPEED AS AN INDICATOR OF SOLAR AND GEOMAGNETIC ACTIVITIES

International Nuclear Information System (INIS)

Kilcik, A.; Yurchyshyn, V. B.; Abramenko, V.; Goode, P. R.; Gopalswamy, N.; Ozguc, A.; Rozelot, J. P.

2011-01-01

We investigate the relationship between the monthly averaged maximal speeds of coronal mass ejections (CMEs), international sunspot number (ISSN), and the geomagnetic Dst and Ap indices covering the 1996-2008 time interval (solar cycle 23). Our new findings are as follows. (1) There is a noteworthy relationship between monthly averaged maximum CME speeds and sunspot numbers, Ap and Dst indices. Various peculiarities in the monthly Dst index are correlated better with the fine structures in the CME speed profile than that in the ISSN data. (2) Unlike the sunspot numbers, the CME speed index does not exhibit a double peak maximum. Instead, the CME speed profile peaks during the declining phase of solar cycle 23. Similar to the Ap index, both CME speed and the Dst indices lag behind the sunspot numbers by several months. (3) The CME number shows a double peak similar to that seen in the sunspot numbers. The CME occurrence rate remained very high even near the minimum of the solar cycle 23, when both the sunspot number and the CME average maximum speed were reaching their minimum values. (4) A well-defined peak of the Ap index between 2002 May and 2004 August was co-temporal with the excess of the mid-latitude coronal holes during solar cycle 23. The above findings suggest that the CME speed index may be a useful indicator of both solar and geomagnetic activities. It may have advantages over the sunspot numbers, because it better reflects the intensity of Earth-directed solar eruptions.

Power converter with maximum power point tracking MPPT for small wind-electric pumping systems

International Nuclear Information System (INIS)

Lara, David; Merino, Gabriel; Salazar, Lautaro

2015-01-01

Highlights: • We implement a wind electric pumping system of small power. • The power converter allowed to change the operating point of the electro pump. • Two control techniques were implemented in the power converter. • The control V/f variable allowed to increase the power generated by the permanent magnet generator. - Abstract: In this work, an AC–DC–AC direct-drive power converter was implemented for a wind electric pumping system consisting of a permanent magnet generator (PMG) of 1.3 kW and a peripheral single phase pump of 0.74 kW. In addition, the inverter linear V/f control scheme and the maximum power point tracking (MPPT) algorithm with variable V/f were developed. MPPT algorithm seeks to extract water in a wide range of power input using the maximum amount of wind power available. Experimental trials at different pump pressures were conducted. With a MPPT tracking system with variable V/f, a power value of 1.3 kW was obtained at a speed of 350 rpm and a maximum operating hydraulic head of 50 m. At lower operating heads pressures (between 10 and 40 m), variable V/f control increases the power generated by the PMG compared to the linear V/f control. This increase ranged between 4% and 23% depending on the operating pressure, with an average of 13%, getting close to the maximum electrical power curve of the PMG. The pump was driven at variable frequency reaching a minimum speed of 0.5 times the rated speed. Efficiency of the power converter ranges between 70% and 95% with a power factor between 0.4 and 0.85, depending on the operating pressure

Spiral CT portography: correlation with different injection rate

International Nuclear Information System (INIS)

Wu Dong; Zhou Kangrong; Chen Zuwang; Chen Gang; Chen Jin; Chen Huiming

2000-01-01

Objective: To choose optimal injection rate in spiral CT portography(CTP) by comparing 3D CTP images using different injection rates. Methods: Thirty-seven patients were randomly divided into 2 groups (11 and 26 cases in each group). Single-level dynamic scan was completed at the first liver hilus, starting at 15s or 30s after initial contrast injection(2 ml/kg) with injection rate 1.5 ml/s (slow group) or 3.0 ml/s (rapid group). The continuous scan were repeated every 5s for 120s or 135s. ROI was used to measure the CT value of the portal vein and the liver parenchyma, respectively, and then the time-density curves were drawn. Spiral CT portography were performed at injection rate of 1.5 ml/s or 3.0 ml/s as the delay time designed described above, including 98 cases in rapid group and 12 cases in slow group. Both MPVR (multi-projection volume reconstruction) and MIP (maximum intensity projection) were employed for reconstruction. All images were ranked according to the grade of portal vein, the different CT value between the portal vein and the liver parenchyma, the edge's definition of blood vessel, the grade of hepatic vein and the display of IVC by 2 radiologists. Results: The maximum density difference in average between the portal vein and the liver parenchyma was 53.4 HU and 83.9 HU, respectively (t = 16.418, P < 0.001) in slow group and rapid one, and the mean reaching time was 80s and 60s, respectively (t = 13.394, P < 0.001). In slow injection group, the average score of MPVR image was 9.3, while it was 12.5 (t = 3.514, P < 0.01) in rapid injection group. Rapid group was better than slow one at the PV-L, the grade of the portal vein, and the edge's definition of blood vessel. Conclusion: Using rapid injection rate (3.0 ml/s), the maximum density difference between the portal vein and the liver parenchyma increases, and the mean reaching time shortens. The quality of 3D CTP image of rapid injection rate (3.0 ml/s) is superior to that of slow injection rate

Parametric optimization of thermoelectric elements footprint for maximum power generation

DEFF Research Database (Denmark)

Rezania, A.; Rosendahl, Lasse; Yin, Hao

2014-01-01

The development studies in thermoelectric generator (TEG) systems are mostly disconnected to parametric optimization of the module components. In this study, optimum footprint ratio of n- and p-type thermoelectric (TE) elements is explored to achieve maximum power generation, maximum cost......-performance, and variation of efficiency in the uni-couple over a wide range of the heat transfer coefficient on the cold junction. The three-dimensional (3D) governing equations of the thermoelectricity and the heat transfer are solved using the finite element method (FEM) for temperature dependent properties of TE...... materials. The results, which are in good agreement with the previous computational studies, show that the maximum power generation and the maximum cost-performance in the module occur at An/Ap

Coronary ligation reduces maximum sustained swimming speed in Chinook salmon, Oncorhynchus tshawytscha

DEFF Research Database (Denmark)

Farrell, A P; Steffensen, J F

1987-01-01

The maximum aerobic swimming speed of Chinook salmon (Oncorhynchus tshawytscha) was measured before and after ligation of the coronary artery. Coronary artery ligation prevented blood flow to the compact layer of the ventricular myocardium, which represents 30% of the ventricular mass, and produced...... a statistically significant 35.5% reduction in maximum swimming speed. We conclude that the coronary circulation is important for maximum aerobic swimming and implicit in this conclusion is that maximum cardiac performance is probably necessary for maximum aerobic swimming performance....

Exchange Rate and Interest Rate in the Monetary Policy Reaction Function

Directory of Open Access Journals (Sweden)

Krušković Borivoje D.

2017-01-01

Full Text Available In recent years there has been a particular interest in the relation between exchange rates and interest rates both in developed countries and emerging countries. This is understandable given the important role that these variables have in determining the movement of nominal and real economic variables, including the movement of domestic inflation, real output, exports and imports, foreign exchange reserves, etc. To realized the importance of the given instruments selected macroeconomic indicators, data analysis (monthly data relating to Serbia was made on the basis of the Transfer Function Model, a data analysis (annual data relating to emerging countries was done on the basis of the Stepvise Multiple Regression model. In the transfer function model we used the Maximum Likelihood method for assessing unknown coefficients. In the gradual multiple regression model we used the Least Square method for the evaluation of unknown coefficients. All indicator values were used in the original unmodified form, i.e. there was no need for a variety of transformations. Empirical analysis showed that the exchange rate is a more significant transmission mechanism than the interest rate both in emerging markets and Serbia.

Reducing biting rates of Aedes aegypti with metofluthrin: investigations in time and space

OpenAIRE

Darbro, Jonathan M.; Muzari, M. Odwell; Giblin, Arthur; Adamczyk, Rebecca M.; Ritchie, Scott A.; Devine, Gregor J.

2017-01-01

Background Indoor residual spraying is key to dengue control in Cairns and other parts of northern Queensland, Australia, where Aedes aegypti is prevalent, but the strategy faces challenges with regards to slow application time and, therefore, community coverage. A faster potential improvement might be the use of polyethylene netting impregnated with the volatile pyrethroid metofluthrin (SumiOne?). This formulation was assessed in rooms in three houses in Cairns, Australia. One emanator was p...

Wavelength selection in injection-driven Hele-Shaw flows: A maximum amplitude criterion

Science.gov (United States)

Dias, Eduardo; Miranda, Jose

2013-11-01

As in most interfacial flow problems, the standard theoretical procedure to establish wavelength selection in the viscous fingering instability is to maximize the linear growth rate. However, there are important discrepancies between previous theoretical predictions and existing experimental data. In this work we perform a linear stability analysis of the radial Hele-Shaw flow system that takes into account the combined action of viscous normal stresses and wetting effects. Most importantly, we introduce an alternative selection criterion for which the selected wavelength is determined by the maximum of the interfacial perturbation amplitude. The effectiveness of such a criterion is substantiated by the significantly improved agreement between theory and experiments. We thank CNPq (Brazilian Sponsor) for financial support.

SCEPTIC, Pressure Drop, Flow Rate, Heat Transfer, Temperature in Reactor Heat Exchanger

International Nuclear Information System (INIS)

Kattchee, N.; Reynolds, W.C.

1975-01-01

1 - Nature of physical problem solved: SCEPTIC is a program for calculating pressure drop, flow rates, heat transfer rates, and temperature in heat exchangers such as fuel elements of typical gas or liquid cooled nuclear reactors. The effects of turbulent and heat interchange between flow passages are considered. 2 - Method of solution: The computation procedure amounts to a nodal of lumped parameter type of calculation. The axial mesh size is automatically selected to assure that a prescribed accuracy of results is obtained. 3 - Restrictions on the complexity of the problem: Maximum number of subchannels is 25, maximum number of heated surfaces is 46

LSHINSE, Air Scattering Neutron and Gamma Dose rates for Complex Shielding Geometry

International Nuclear Information System (INIS)

Baran, A.; Gruen, M.; Leicht, R.

1991-01-01

1 - Description of program or function: The program LSHINSE is used to calculate the flux and the dose rate caused by gamma radiation emanating from a point source and being scattered in surrounding air. The program considers all forms of single scattering. Multiple scattering is taken into account in an approximate way by use of buildup factors. 2 - Method of solution: The program LSHINSE solves the equations for skyshine by use of Simpson integration. The integration limits are chosen such that the partial shielding is approximated by rectangular walls around the source. In addition, the attenuation of the primary radiation by a room ceiling can be calculated for several materials. By giving the height of the ceiling, the scattering in the air of the room can be calculated. By specifying energy groups the spectrum of the scattered radiation can be obtained. Valid energy range is 0.1 - 0.2 MeV, where the lower limit is due to uncertainties in the buildup factors. 3 - Restrictions on the complexity of the problem: The program is restricted to rectangular shielding problems involving gamma radiation in the range of 0.1 to 2.0 MeV

Effects of bruxism on the maximum bite force

Directory of Open Access Journals (Sweden)

Todić Jelena T.

2017-01-01

Full Text Available Background/Aim. Bruxism is a parafunctional activity of the masticatory system, which is characterized by clenching or grinding of teeth. The purpose of this study was to determine whether the presence of bruxism has impact on maximum bite force, with particular reference to the potential impact of gender on bite force values. Methods. This study included two groups of subjects: without and with bruxism. The presence of bruxism in the subjects was registered using a specific clinical questionnaire on bruxism and physical examination. The subjects from both groups were submitted to the procedure of measuring the maximum bite pressure and occlusal contact area using a single-sheet pressure-sensitive films (Fuji Prescale MS and HS Film. Maximal bite force was obtained by multiplying maximal bite pressure and occlusal contact area values. Results. The average values of maximal bite force were significantly higher in the subjects with bruxism compared to those without bruxism (p 0.01. Maximal bite force was significantly higher in the males compared to the females in all segments of the research. Conclusion. The presence of bruxism influences the increase in the maximum bite force as shown in this study. Gender is a significant determinant of bite force. Registration of maximum bite force can be used in diagnosing and analysing pathophysiological events during bruxism.

Allometric equations for maximum filtration rate in blue mussels Mytilus edulis and importance of condition index

DEFF Research Database (Denmark)

Riisgård, Hans Ulrik; Larsen, Poul Scheel; Pleissner, Daniel

2014-01-01

rate (F, l h-1), W (g), and L (mm) as described by the equations: FW = aWb and FL = cLd, respectively. This is done by using available and new experimental laboratory data on M. edulis obtained by members of the same research team using different methods and controlled diets of cultivated algal cells...

Neural Network Based Maximum Power Point Tracking Control with Quadratic Boost Converter for PMSG—Wind Energy Conversion System

Directory of Open Access Journals (Sweden)

Ramji Tiwari

2018-02-01

Full Text Available This paper proposes an artificial neural network (ANN based maximum power point tracking (MPPT control strategy for wind energy conversion system (WECS implemented with a DC/DC converter. The proposed topology utilizes a radial basis function network (RBFN based neural network control strategy to extract the maximum available power from the wind velocity. The results are compared with a classical Perturb and Observe (P&O method and Back propagation network (BPN method. In order to achieve a high voltage rating, the system is implemented with a quadratic boost converter and the performance of the converter is validated with a boost and single ended primary inductance converter (SEPIC. The performance of the MPPT technique along with a DC/DC converter is demonstrated using MATLAB/Simulink.

77 FR 38397 - Agency Information Collection (Interest Rate Reduction Refinancing Loan Worksheet) Activities...

Science.gov (United States)

2012-06-27

... . Please refer to ``OMB Control No. 2900- 0386.'' SUPPLEMENTARY INFORMATION: Title: Interest Rate Reduction... guaranty on all interest rate reduction refinancing loan and provide a receipt as proof that the funding... ensure lenders computed the funding fee and the maximum permissible loan amount for interest rate...

Effects of sublethal exposure to metofluthrin on the fitness of Aedes aegypti in a domestic setting in Cairns, Queensland.

Science.gov (United States)

Buhagiar, Tamara S; Devine, Gregor J; Ritchie, Scott A

2017-05-31

Metofluthrin is highly effective at reducing biting activity in Aedes aegypti. Its efficacy lies in the rapid onset of confusion, knockdown, and subsequent kill of a mosquito. In the field, there are a variety of scenarios that might result in sublethal exposure to metofluthrin, including mosquitoes that are active at the margins of the chemical's lethal range, brief exposure as mosquitoes fly in and out of treated spaces or decreasing efficacy of the emanators with time. Sublethal effects are key elements of insecticide exposure and selection. The metofluthrin dose for each treatment group of male and female Ae. aegypti was controlled using exposure time intervals to a 10% active ingredient (AI) metofluthrin emanator. Room size and distance from the emanator for all groups was maintained at 3 m. In bioassay cages, male Ae. aegypti were exposed at 0, 5, 10, 20, 30 and 40-min intervals. Females were exposed in bioassay cages at 0, 10, 20, 30, 40 and 60-min intervals. Mortality rates and fecundity were observed between the exposure time groups for both sexes. Female Ae. aegypti exposed for 60 min had a significantly higher mortality rate (50%), after a 24-h recovery period, than other exposure times, 10, 20, 30 and 40 min (P metofluthrin exposure were as likely to produce viable eggs with an unexposed female as males that had not been exposed (P > 0.05). Regardless of sex, if a mosquito survived exposure, it would be as biologically successful as its unexposed counterpart. Portability of the metofluthrin emanator and delayed knockdown effects create opportunities for sublethal exposure and potential pyrethroid resistance development in Ae. aegypti, and should be taken into consideration in recommendations for field application of this product, including minimum exposure periods and a prescribed number of emanators per room based on volume.

Acumulación de hojarasca en un pastizal de Panicum maximum y en un sistema silvopastoril de Panicum maximum y Leucaena leucocephala Litter accumulation in a Panicum maximum grassland and in a silvopastoral system of Panicum maximum and Leucaena leucocephala

Directory of Open Access Journals (Sweden)

Saray Sánchez

2007-09-01

Full Text Available Se realizó un estudio en la Estación Experimental de Pastos y Forrajes "Indio Hatuey", Matanzas, Cuba, con el objetivo de determinar la acumulación de la hojarasca en un pastizal de Panicum maximum Jacq cv. Likoni y en un sistema silvopastoril de Panicum maximum y Leucaena leucocephala (Lam de Wit cv. Cunningham. En los pastizales de P. maximum de ambos sistemas se determinó la acumulación de la hojarasca según la técnica propuesta por Bruce y Ebershon (1982, mientras que la hojarasca de L. leucocephala acumulada en el sistema silvopastoril se determinó según Santa Regina et al. (1997. De forma general, los resultados demostraron que en ambos pastizales la guinea acumuló una menor cantidad de hojarasca durante el período junio-diciembre, etapa en la que se produce su mayor desarrollo vegetativo. En la leucaena la mayor producción de hojarasca ocurrió en el período de diciembre a enero, asociada con la caída natural de sus hojas que se produce por efecto de las temperaturas más bajas y la escasa humedad en el suelo. En el sistema silvopastoril la hojarasca de leucaena representó el mayor porcentaje de peso dentro de la producción total, con un contenido más alto de nitrógeno y de calcio que el de la hojarasca del estrato herbáceo. En la guinea la lluvia fue el factor climático que mayor correlación negativa presentó con la producción de hojarasca en ambos sistemas, y en la leucaena la mayor correlación negativa se encontró con la temperatura mínima.A study was carried out at the Experimental Station of Pastures and Forages "Indio Hatuey", Matanzas, Cuba, with the objective of determining the litter accumulation in a pastureland of Panicum maximum Jacq cv. Likoni and in a silvopastoral system of Panicum maximum and Leucaena leucocephala (Lam de Wit cv. Cunningham. In the P. maximum pasturelands of both systems the litter accumulation was determined by means of the technique proposed by Bruce and Ebershon (1982, while

Parameters determining maximum wind velocity in a tropical cyclone

International Nuclear Information System (INIS)

Choudhury, A.M.

1984-09-01

The spiral structure of a tropical cyclone was earlier explained by a tangential velocity distribution which varies inversely as the distance from the cyclone centre outside the circle of maximum wind speed. The case has been extended in the present paper by adding a radial velocity. It has been found that a suitable combination of radial and tangential velocities can account for the spiral structure of a cyclone. This enables parametrization of the cyclone. Finally a formula has been derived relating maximum velocity in a tropical cyclone with angular momentum, radius of maximum wind speed and the spiral angle. The shapes of the spirals have been computed for various spiral angles. (author)

Novel Fingertip Image-Based Heart Rate Detection Methods for a Smartphone

Directory of Open Access Journals (Sweden)

Rifat Zaman

2017-02-01

Full Text Available We hypothesize that our fingertip image-based heart rate detection methods using smartphone reliably detect the heart rhythm and rate of subjects. We propose fingertip curve line movement-based and fingertip image intensity-based detection methods, which both use the movement of successive fingertip images obtained from smartphone cameras. To investigate the performance of the proposed methods, heart rhythm and rate of the proposed methods are compared to those of the conventional method, which is based on average image pixel intensity. Using a smartphone, we collected 120 s pulsatile time series data from each recruited subject. The results show that the proposed fingertip curve line movement-based method detects heart rate with a maximum deviation of 0.0832 Hz and 0.124 Hz using time- and frequency-domain based estimation, respectively, compared to the conventional method. Moreover, another proposed fingertip image intensity-based method detects heart rate with a maximum deviation of 0.125 Hz and 0.03 Hz using time- and frequency-based estimation, respectively.

Electron density distribution in Si and Ge using multipole, maximum ...

Indian Academy of Sciences (India)

Si and Ge has been studied using multipole, maximum entropy method (MEM) and ... and electron density distribution using the currently available versatile ..... data should be subjected to maximum possible utility for the characterization of.

Hollow-duct radiation delivery system investigation

Directory of Open Access Journals (Sweden)

Kramer D.

2013-05-01

Full Text Available Investigation of hollow-duct structure for high-power laser-diode-array radiation delivery into the end-pumped large-aperture gain media is reported. A ray tracing method has been used to evaluate the performance of the structure designed for maximum transmission efficiency and output beam profile homogeneity. Variable hollow-duct lengths as well as emanating angles of laser-diode-array have been taken into account.

The maximum-entropy method in superspace

Czech Academy of Sciences Publication Activity Database

van Smaalen, S.; Palatinus, Lukáš; Schneider, M.

2003-01-01

Roč. 59, - (2003), s. 459-469 ISSN 0108-7673 Grant - others:DFG(DE) XX Institutional research plan: CEZ:AV0Z1010914 Keywords : maximum-entropy method, * aperiodic crystals * electron density Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.558, year: 2003

Maximum-entropy clustering algorithm and its global convergence analysis

Institute of Scientific and Technical Information of China (English)

无

2001-01-01

Constructing a batch of differentiable entropy functions touniformly approximate an objective function by means of the maximum-entropy principle, a new clustering algorithm, called maximum-entropy clustering algorithm, is proposed based on optimization theory. This algorithm is a soft generalization of the hard C-means algorithm and possesses global convergence. Its relations with other clustering algorithms are discussed.

Temporal relationships between the variations of diffuse gaseous emanations and the explosive activity of some active volcanoes of Costa-Rica, examples at the Arenal, Irazu and at the Rincon de la Vieja; Relations temporelles entre les variations des emanations gazeuses diffuses et l`activite explosive de quelques volcans actifs du Costa-Rica, exemples a l`Arenal, l`Irazu et au Rincon de la Vieja

Energy Technology Data Exchange (ETDEWEB)

Baubron, J C [BRGM, 45 - Orleans (France); Allard, P [CEA Centre d` Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France). Direction des Sciences de la Matiere; Fernandez, E [Obviscori, Heridia (Costa Rica); Hammouya, G [Observatoire de la Soufriere, IPG-P, le Houelmont, 97 - Gourgeyre (France); Soto, G J [ICE, San Jose (Costa Rica)

1997-12-31

The surveillance of the temporal evolution of radon and helium concentrations in the carbon dioxide of crater fumaroles and gaseous emanations is performed since 1992 on the Irazu, Arenal, Poas and Rincon de la Vieja volcanoes in Costa-Rica. The {sup 3}He/{sup 4}He ratio is used as an indicator of the deep origin of the volcanic gas while radon is an indicator of the CO{sub 2} flux. Radon measurements performed on the Irazu show a continuous decay of radon concentration in the intra-crater fumaroles with an important increase of the gaseous flux since 1992. On the contrary, the external fumaroles on the NW flank were characterized by an important increase in radon concentration in 1994 with a stable flux. The radon surveillance performed in soils around the volcano has shown an intense increase of the diffuse gaseous flows probably linked to the micro-seismic activity of the volcano. Similar observations are reported for the Rincon de la Vieja volcano and correlated with its eruptive history and its phreatic and phreato-magmatic activity. Short paper. (J.S.).

Temporal relationships between the variations of diffuse gaseous emanations and the explosive activity of some active volcanoes of Costa-Rica, examples at the Arenal, Irazu and at the Rincon de la Vieja; Relations temporelles entre les variations des emanations gazeuses diffuses et l`activite explosive de quelques volcans actifs du Costa-Rica, exemples a l`Arenal, l`Irazu et au Rincon de la Vieja

Energy Technology Data Exchange (ETDEWEB)

Baubron, J.C. [BRGM, 45 - Orleans (France); Allard, P. [CEA Centre d`Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France). Direction des Sciences de la Matiere; Fernandez, E. [Obviscori, Heridia (Costa Rica); Hammouya, G. [Observatoire de la Soufriere, IPG-P, le Houelmont, 97 - Gourgeyre (France); Soto, G.J. [ICE, San Jose (Costa Rica)

1996-12-31

The surveillance of the temporal evolution of radon and helium concentrations in the carbon dioxide of crater fumaroles and gaseous emanations is performed since 1992 on the Irazu, Arenal, Poas and Rincon de la Vieja volcanoes in Costa-Rica. The {sup 3}He/{sup 4}He ratio is used as an indicator of the deep origin of the volcanic gas while radon is an indicator of the CO{sub 2} flux. Radon measurements performed on the Irazu show a continuous decay of radon concentration in the intra-crater fumaroles with an important increase of the gaseous flux since 1992. On the contrary, the external fumaroles on the NW flank were characterized by an important increase in radon concentration in 1994 with a stable flux. The radon surveillance performed in soils around the volcano has shown an intense increase of the diffuse gaseous flows probably linked to the micro-seismic activity of the volcano. Similar observations are reported for the Rincon de la Vieja volcano and correlated with its eruptive history and its phreatic and phreato-magmatic activity. Short paper. (J.S.).

Productivity feedback did not terminate the Paleocene-Eocene Thermal Maximum (PETM

Directory of Open Access Journals (Sweden)

A. Torfstein

2010-04-01

Full Text Available The Paleocene-Eocene Thermal Maximum (PETM occurred approximately 55 million years ago, and is one of the most dramatic abrupt global warming events in the geological record. This warming was triggered by the sudden release of thousands of gigatons of carbon into the atmosphere and is widely perceived to be the best analogue for current anthropogenic climate change. Yet, the mechanism of recovery from this event remains controversial. A massive increase in the intensity of the marine biological pump ("productivity feedback" has been suggested to cause a drawdown of atmospheric CO₂ and subsequent carbon sequestration in the ocean. A re-evaluation of the "productivity feedback hypothesis", based on biogenic barium mass accumulation rates (Ba-MARs for a site in the Southern Ocean, finds that any increase in export production lagged the initial carbon release by at least ~70 000 years. This implies that export production did not facilitate rapid removal of excess carbon from the atmosphere. Thus, the most likely mechanism for carbon removal appears to be silicate weathering, which occurred at much slower rates than previously assumed.

Multiple Maximum Exposure Rates in Computerized Adaptive Testing

Science.gov (United States)

Ramon Barrada, Juan; Veldkamp, Bernard P.; Olea, Julio

2009-01-01

Computerized adaptive testing is subject to security problems, as the item bank content remains operative over long periods and administration time is flexible for examinees. Spreading the content of a part of the item bank could lead to an overestimation of the examinees' trait level. The most common way of reducing this risk is to impose a…

On Maximum Likelihood Estimation for Left Censored Burr Type III Distribution

Directory of Open Access Journals (Sweden)

Navid Feroze

2015-12-01

Full Text Available Burr type III is an important distribution used to model the failure time data. The paper addresses the problem of estimation of parameters of the Burr type III distribution based on maximum likelihood estimation (MLE when the samples are left censored. As the closed form expression for the MLEs of the parameters cannot be derived, the approximate solutions have been obtained through iterative procedures. An extensive simulation study has been carried out to investigate the performance of the estimators with respect to sample size, censoring rate and true parametric values. A real life example has also been presented. The study revealed that the proposed estimators are consistent and capable of providing efficient results under small to moderate samples.

maximum neutron flux at thermal nuclear reactors

International Nuclear Information System (INIS)

Strugar, P.

1968-10-01

Since actual research reactors are technically complicated and expensive facilities it is important to achieve savings by appropriate reactor lattice configurations. There is a number of papers, and practical examples of reactors with central reflector, dealing with spatial distribution of fuel elements which would result in higher neutron flux. Common disadvantage of all the solutions is that the choice of best solution is done starting from the anticipated spatial distributions of fuel elements. The weakness of these approaches is lack of defined optimization criteria. Direct approach is defined as follows: determine the spatial distribution of fuel concentration starting from the condition of maximum neutron flux by fulfilling the thermal constraints. Thus the problem of determining the maximum neutron flux is solving a variational problem which is beyond the possibilities of classical variational calculation. This variational problem has been successfully solved by applying the maximum principle of Pontrjagin. Optimum distribution of fuel concentration was obtained in explicit analytical form. Thus, spatial distribution of the neutron flux and critical dimensions of quite complex reactor system are calculated in a relatively simple way. In addition to the fact that the results are innovative this approach is interesting because of the optimization procedure itself [sr