Non-thermal Power-Law Distributions in Solar and Space Plasmas

Science.gov (United States)

Oka, M.; Battaglia, M.; Birn, J.; Chaston, C. C.; Effenberger, F.; Eriksson, E.; Fletcher, L.; Hatch, S.; Imada, S.; Khotyaintsev, Y. V.; Kuhar, M.; Livadiotis, G.; Miyoshi, Y.; Retino, A.

2017-12-01

Particles are accelerated to very high, non-thermal energies in solar and space plasma environments. While energy spectra of accelerated particles often exhibit a power-law and are characterized by the power-law index δ, it remains unclear how particles are accelerated to high energies and how δ is determined. Here, we review previous observations of the power-law index δ in a variety of different plasma environments with a particular focus on sub-relativistic electrons. It appears that in regions more closely related to magnetic reconnection (such as the "above-the-looptop" solar hard X-ray source and the plasma sheet in Earth's magnetotail), the spectra are typically soft (δ> 4). This is in contrast to the typically hard spectra (δuniform in the plasma sheet, while power-law distributions still exist even in quiet times. The role of magnetotail reconnection in the electron power-law formation could therefore be confounded with these background conditions. Because different regions have been studied with different instrumentations and methodologies, we point out a need for more systematic and coordinated studies of power-law distributions for a better understanding of possible scaling laws in particle acceleration as well as their universality.

Numerical investigation of magnetohydrodynamic slip flow of power-law nanofluid with temperature dependent viscosity and thermal conductivity over a permeable surface

Directory of Open Access Journals (Sweden)

Hussain Sajid

2017-12-01

Full Text Available In this paper, a numerical investigation is carried out to study the effect of temperature dependent viscosity and thermal conductivity on heat transfer and slip flow of electrically conducting non-Newtonian nanofluids. The power-law model is considered for water based nanofluids and a magnetic field is applied in the transverse direction to the flow. The governing partial differential equations(PDEs along with the slip boundary conditions are transformed into ordinary differential equations(ODEs using a similarity technique. The resulting ODEs are numerically solved by using fourth order Runge-Kutta and shooting methods. Numerical computations for the velocity and temperature profiles, the skin friction coefficient and the Nusselt number are presented in the form of graphs and tables. The velocity gradient at the boundary is highest for pseudoplastic fluids followed by Newtonian and then dilatant fluids. Increasing the viscosity of the nanofluid and the volume of nanoparticles reduces the rate of heat transfer and enhances the thickness of the momentum boundary layer. The increase in strength of the applied transverse magnetic field and suction velocity increases fluid motion and decreases the temperature distribution within the boundary layer. Increase in the slip velocity enhances the rate of heat transfer whereas thermal slip reduces the rate of heat transfer.

Source index A: Federal law, without agreements under international law. As of December 31, 1994

International Nuclear Information System (INIS)

1995-01-01

The Federal Law Catalogue and relevant sources - BGBl. III - is the basis of the source index A, which from 1st January 1966 onwards publishes the sources of laws and statutes announced in the Federal Law Gazette, part I and part II, as well as in the Federal Gazette. The source index A covers the sources of all statutes and amendments since 1st January 1964. Official directives, however, are not always announced in the Federal Law Gazette, or in the promulgation section of the Federal Gazette, but rather in the official journals of the Federal Ministries, and in the announcement section of the Federal Gazette. This also applies to amendments or cancellations of directives first published in the Federal Law Gazette or in the promulgation section of the Federal Gazette. As the latter and the official journals on the ministries are not scanned for the source index A, there is no guarantee as to complete coverage of directives. Subject scope 75 covers acts and directives relating to mining, nuclear energy, electricity, gas and power supply. (orig.) [de

Analytical Solution of Unsteady Gravity Flows of A Power-Law Fluid ...

African Journals Online (AJOL)

We present an analytical study of unsteady non-linear rheological effects of a power-law fluid under gravity. The fluid flows through a porous medium. The governing equations are derived and similarity solutions are determined. The results show the existence of traveling waves. It is assumed that the viscosity is temperature ...

Electroviscous effects in steady fully developed flow of a power-law liquid through a cylindrical microchannel

International Nuclear Information System (INIS)

Bharti, Ram P.; Harvie, Dalton J.E.; Davidson, Malcolm R.

2009-01-01

Electroviscous effects in steady, fully developed, pressure-driven flow of power-law liquids through a uniform cylindrical microchannel have been investigated numerically by solving the Poisson-Boltzmann and the momentum equations using a finite difference method. The pipe wall is considered to have uniform surface charge density and the liquid is assumed to be a symmetric 1:1 electrolyte solution. Electroviscous resistance reduces the velocity adjacent to the wall, relative to the velocity on the axis. The effect is shown to be greater when the liquid is shear-thinning, and less when it is shear-thickening, than it is for Newtonian flow. For overlapping electrical double layers and elevated surface charge density, the electroviscous reduction in the near-wall velocity can form an almost stationary (zero shear) layer there when the liquid is shear-thinning. In that case, the liquid behaves approximately as if it is flowing through a channel of reduced diameter. The induced axial electrical field shows only a weak dependence on the power-law index with the dependence being greatest for shear-thinning liquids. This field exhibits a local maximum as surface charge density increases from zero, even though the corresponding electrokinetic resistance increases monotonically. The magnitude of the electroviscous effect on the apparent viscosity, as measured by the ratio of the apparent and physical consistency indices, decreases monotonically as the power-law index increases. Thus, overall, the electroviscous effect is stronger in shear-thinning, and weaker in shear-thickening liquids, than it is when the liquid is Newtonian.

Nuclear Law Bulletin Index Nos. 1 to 99

International Nuclear Information System (INIS)

2017-01-01

This new edition of the Nuclear Law Bulletin Index covers the first 99 issues of the Nuclear Law Bulletin (NLB). By established practice, the plan of the Index is not a replica of the Bulletin, as it was considered more useful for research purposes to group together all the information concerning legislative and regulatory activities, case law and bilateral agreements and to classify this information by country. Following classification by country, references to the work of international organisations, multilateral agreements, studies and articles are set out in separate sections. The 'Bibliography and News Briefs' section is omitted from the Index. A separate chapter of the Index has been devoted to the listing of the instruments published in the Supplements to the Bulletin, or in the Chapter 'Texts' from past Bulletins, up until the present date. Each item in the Index is followed by a reference to the relevant Bulletin. Legislative and regulatory texts, as well as agreements reproduced in the Bulletins or their Supplements, are also referenced. Plan of index: 1 - Reports and commentary 1a - Classification by country Legislative and regulatory activities (Environmental protection, Food irradiation, General legislation, regulations and instruments, International co-operation, Liability and compensation, Licensing and regulatory infrastructure, Nuclear installations, Nuclear safety and radiological protection - including nuclear emergency planning, Nuclear security, Nuclear trade - including non-proliferation, Nuclear-powered ships, Organisation and structure, Radioactive materials - including physical protection, Radioactive waste management, Transport of radioactive materials); Case law; Administrative decisions; Agreements; 1b - International organisations; 1c - Multilateral agreements; 2 - Studies and articles; 3 - Texts reproduced in the nuclear law bulletin; 3a - Classification by country; 3b - International organisations; 3c

Multitude scaling laws in axisymmetric turbulent wake

Science.gov (United States)

Layek, G. C.; Sunita

2018-03-01

We establish theoretically multitude scaling laws of a self-similar (statistical) axisymmetric turbulent wake. At infinite Reynolds number limit, the flow evolves as general power law and a new exponential law of streamwise distance, consistent with the criterion of equilibrium similarity hypothesis. We found power law scalings for components of the homogeneous dissipation rate (ɛ) obeying the non-Richardson-Kolmogorov cascade as ɛu˜ku3 /2/(l R elm ) , ɛv˜kv3 /2/l , kv˜ku/R el2 m, 0 stress, l is the local length scale, and Rel is the Reynolds number. The Richardson-Kolmogorov cascade corresponds to m = 0. For m ≈ 1, the power law agrees with non-equilibrium scaling laws observed in recent experiments of the axisymmetric wake. On the contrary, the exponential scaling law follows the above dissipation law with different regions of existence for power index m = 3. At finite Reynolds number with kinematic viscosity ν, scalings obey the dissipation laws ɛu ˜ νku/l2 and ɛv ˜ νkv/l2 with kv˜ku/R eln. The value of n is preferably 0 and 2. Different possibilities of scaling laws and symmetry breaking process are discussed at length.

Numerical Study of the Magnetic Field Effects on the Heat Transfer and Entropy Generation Aspects of a Power Law Fluid over an Axisymmetric Stretching Plate Structure

Directory of Open Access Journals (Sweden)

Payam Hooshmand

2017-03-01

Full Text Available Numerical investigation of the effects of magnetic field strength, thermal radiation, Joule heating, and viscous heating on a forced convective flow of a non-Newtonian, incompressible power law fluid in an axisymmetric stretching sheet with variable temperature wall is accomplished. The power law shear thinning viscosity-shear rate model for the anisotropic solutions and the Rosseland approximation for the thermal radiation through a highly absorbing medium are considered. The temperature dependent heat sources, Joule heating, and viscous heating are considered as the source terms in the energy balance. The non-dimensional boundary layer equations are solved numerically in terms of similarity variable. A parameter study on the Nusselt number, viscous components of entropy generation, and thermal components of entropy generation in fluid is performed as a function of thermal radiation parameter (0 to 2, Brinkman number (0 to 10, Prandtl number (0 to 10, Hartmann number (0 to 1, power law index (0 to 1, and heat source coefficient (0 to 0.1.

Power-law to Power-law Mapping of Blazar Spectra from Intergalactic Absorption

International Nuclear Information System (INIS)

Stecker, F W; Scully, S T

2007-01-01

We have derived a useful analytic approximation for determining the effect of intergalactic absorption on the γ-ray spectra of TeV blazars the energy range 0.2 TeV γ γ ) is approximately logarithmic. The effect of this energy dependence is to steepen intrinsic source spectra such that a source with an approximate power-law spectral index Γ s is converted to one with an observed spectral index Γ o ≅ Γ s + ΔΓ(z) where ΔΓ(z) is a linear function of z in the redshift range 0.05-0.4. We apply this approximation to the spectra of 7 TeV blazars

Vibration analysis of FG cylindrical shells with power-law index using discrete singular convolution technique

Science.gov (United States)

Mercan, Kadir; Demir, Çiǧdem; Civalek, Ömer

2016-01-01

In the present manuscript, free vibration response of circular cylindrical shells with functionally graded material (FGM) is investigated. The method of discrete singular convolution (DSC) is used for numerical solution of the related governing equation of motion of FGM cylindrical shell. The constitutive relations are based on the Love's first approximation shell theory. The material properties are graded in the thickness direction according to a volume fraction power law indexes. Frequency values are calculated for different types of boundary conditions, material and geometric parameters. In general, close agreement between the obtained results and those of other researchers has been found.

Resurrecting power law inflation in the light of Planck results

International Nuclear Information System (INIS)

Unnikrishnan, Sanil; Sahni, Varun

2013-01-01

It is well known that a canonical scalar field with an exponential potential can drive power law inflation (PLI). However, the tensor-to-scalar ratio in such models turns out to be larger than the stringent limit set by recent Planck results. We propose a new model of power law inflation for which the scalar spectra index, the tensor-to-scalar ratio and the non-gaussianity parameter f NL equil are in excellent agreement with Planck results. Inflation, in this model, is driven by a non-canonical scalar field with an inverse power law potential. The Lagrangian for our model is structurally similar to that of a canonical scalar field and has a power law form for the kinetic term. A simple extension of our model resolves the graceful exit problem which usually afflicts models of power law inflation

Viscosity of Heterogeneous Silicate Melts: A Non-Newtonian Model

Science.gov (United States)

Liu, Zhuangzhuang; Blanpain, Bart; Guo, Muxing

2017-12-01

The recently published viscosity data of heterogeneous silicate melts with well-documented structure and experimental conditions are critically re-analyzed and tabulated. By using these data, a non-Newtonian viscosity model incorporating solid fraction, solid shape, and shear rate is proposed on the basis of the power-law equation. This model allows calculating the viscosity of the heterogeneous silicate melts with solid fraction up to 34 vol pct. The error between the calculated and measured data is evaluated to be 32 pct, which is acceptable considering the large error in viscosity measurement of the completely liquid silicate melt.

Numerical viscosity of entropy stable schemes for systems of conservation laws. Final Report

International Nuclear Information System (INIS)

Tadmor, E.

1985-11-01

Discrete approximations to hyperbolic systems of conservation laws are studied. The amount of numerical viscosity present in such schemes is quantified and related to their entropy stability by means of comparison. To this end conservative schemes which are also entropy conservative are constructed. These entropy conservative schemes enjoy second-order accuracy; moreover, they admit a particular interpretation within the finite-element frameworks, and hence can be formulated on various mesh configurations. It is then shown that conservative schemes are entropy stable if and only if they contain more viscosity than the mentioned above entropy conservative ones

New instrument for on-line viscosity measurement of fermentation media.

Science.gov (United States)

Picque, D; Corrieu, G

1988-01-01

In an attempt to resolve the difficult problem of on-line determination of the viscosity of non-Newtonian fermentation media, the authors have used a vibrating rod sensor mounted on a bioreactor. The sensor signal decreases nonlinearly with increased apparent viscosity. Electronic filtering of the signal damps the interfering effect of aeration and mechanical agitation. Sensor drift is very low (0.03% of measured value per hour). On the rheological level the sensor is primarily an empirical tool that must be specifically calibrated for each fermentation process. Once this is accomplished, it becomes possible to establish linear or second-degree correlations between the electrical signal from the sensor and the essential parameters of the fermentation process in question (pH of a fermented milk during acidification, concentration of extra cellular polysaccharide). In addition, by applying the power law to describe the rheological behavior of fermentation media, we observe a second-order polynomial correlation between the sensor signal and the behavior index (n).

Entropy Viscosity Method for High-Order Approximations of Conservation Laws

KAUST Repository

Guermond, J. L.

2010-09-17

A stabilization technique for conservation laws is presented. It introduces in the governing equations a nonlinear dissipation function of the residual of the associated entropy equation and bounded from above by a first order viscous term. Different two-dimensional test cases are simulated - a 2D Burgers problem, the "KPP rotating wave" and the Euler system - using high order methods: spectral elements or Fourier expansions. Details on the tuning of the parameters controlling the entropy viscosity are given. © 2011 Springer.

Entropy Viscosity Method for High-Order Approximations of Conservation Laws

KAUST Repository

Guermond, J. L.; Pasquetti, R.

2010-01-01

A stabilization technique for conservation laws is presented. It introduces in the governing equations a nonlinear dissipation function of the residual of the associated entropy equation and bounded from above by a first order viscous term. Different two-dimensional test cases are simulated - a 2D Burgers problem, the "KPP rotating wave" and the Euler system - using high order methods: spectral elements or Fourier expansions. Details on the tuning of the parameters controlling the entropy viscosity are given. © 2011 Springer.

Influence of power-law index on an unsteady exothermic reaction ...

African Journals Online (AJOL)

This study presents the solution of an unsteady Arrhenius exothermic reaction where we reduced the exponential term to a power-law approximation. A numerical solution of the problem is obtained using shooting technique with second order Runge-Kuta scheme. It is shown that the temperature of the reactant depends on ...

Wind Energy Potential and Power Law Indexes Assessment for Selected Near-Coastal Sites in Malaysia

Directory of Open Access Journals (Sweden)

Aliashim Albani

2017-03-01

Full Text Available This paper investigated the wind energy potential by analysing a certain amount of gathered 10-min measured data at four stations located at coastal sites in Malaysia, i.e., Kudat, Mersing, Kijal, and Langkawi. The wind data are collected from a total of four new wind measurement masts with sensors mounted at various heights on the tower. The measured data have enabled the establishment of wind resource maps and the power law indexes (PLIs analysis. In addition, the dependence of PLI upon surface temperature and terrain types is studied, as they are associated to the form of exponential fits. Moreover, the accuracy of exponential fits is assessed by comparing the results with the 1/7 law via the capacity factor (CF discrepancies. In order to do so, the wind turbine with a hub-height similar to the maximum height of the measured data at each site is selected to simulate energy production. Accordingly, the discrepancy of CF based on the extrapolated data by employing 1/7 laws and exponential fits, in spite of being computed using measured data, is determined as well. Furthermore, the large discrepancy of the wind data and the CF, which has been determined with the application of 1/7, is compared to the exponential fits. This is because; discrepancy in estimation of vertical wind speed could lead to inaccurate CF computation. Meanwhile, from the energy potential analysis based on the computed CF, only Kudat and Mersing display a promising potential to develop a medium capacity of wind turbine power, while the other sites may be suitable for wind turbines at a small scale.

Unconfined Unsteady Laminar Flow of a Power-Law Fluid across a Square Cylinder

Directory of Open Access Journals (Sweden)

Asterios Pantokratoras

2016-11-01

Full Text Available The flow of a non-Newtonian, power-law fluid, directed normally to a horizontal cylinder with square cross-section (two-dimensional flow is considered in the present paper. The problem is investigated numerically with a very large calculation domain in order that the flow could be considered unconfined. The investigation covers the power-law index from 0.1 up to 2 and the Reynolds number ranges from 60 to 160. Over this range of Reynolds numbers the flow is unsteady. It is found that the drag coefficient and the Strouhal number are higher in a confined flow compared to those of an unconfined flow. In addition some flow characteristics are lost in a confined flow. Complete results for the drag coefficient and Strouhal number in the entire shear-thinning and shear-thickening region have been produced. In shear-thinning fluids chaotic structures exist which diminish at higher values of power-law index. This study represents the first investigation of unsteady, non-Newtonian power-law flow past a square cylinder in an unconfined field.

Breakup characteristics of power-law liquid sheets formed by two impinging jets

International Nuclear Information System (INIS)

Bai, Fuqiang; Diao, Hai; Chang, Qing; Wang, Endong; Du, Qing; Zhang, Mengzheng

2014-01-01

The breakup characteristics of the shear-thinning power-law liquid sheets formed by two impinging jets have been investigated with the shadowgraph technique. This paper focuses on the effects of spray parameters (jet velocity), physical parameters (viscosity) and geometry parameters (impinging angle and nozzle cross-sectional shape) on the breakup behaviors of liquid sheets. The breakup mode, sheet length and expansion angle of the sheet are extracted from the spray images obtained by a high speed camera. Impinging angle and Weber number play the similar roles in promoting the breakup of liquid sheets. With the increase of jet velocity, five different breakup modes are observed and the expansion angle increases consistently after the closed-rim mode while the sheet length first increases and then decreases. But there exists a concave consisting of a fierce drop and a second rising process on the sheet length curve for the fluid with smaller viscosity. Different nozzle cross-sectional shapes emphasize significant effects on the sheet length and expansion angle of liquid sheets. At a fixed Weber number, the liquid sheet with greater viscosity has a greater sheet length and a smaller expansion angle due to the damping effect of viscosity. (papers)

Reduced viscosity interpreted for fluid/gas mixtures

Science.gov (United States)

Lewis, D. H.

1981-01-01

Analysis predicts decrease in fluid viscosity by comparing pressure profile of fluid/gas mixture with that of power-law fluid. Fluid is taken to be viscous, non-Newtonian, and incompressible; the gas to be ideal; the flow to be inertia-free, isothermal, and one dimensional. Analysis assists in design of flow systems for petroleum, coal, polymers, and other materials.

Thermal conductivity as influenced by the temperature and apparent viscosity of dairy products.

Science.gov (United States)

Gonçalves, B J; Pereira, C G; Lago, A M T; Gonçalves, C S; Giarola, T M O; Abreu, L R; Resende, J V

2017-05-01

This study aimed to evaluate the rheological behavior and thermal conductivity of dairy products, composed of the same chemical components but with different formulations, as a function of temperature. Subsequently, thermal conductivity was related to the apparent viscosity of yogurt, fermented dairy beverage, and fermented milk. Thermal conductivity measures and rheological tests were performed at 5, 10, 15, 20, and 25°C using linear probe heating and an oscillatory rheometer with concentric cylinder geometry, respectively. The results were compared with those calculated using the parallel, series, and Maxwell-Eucken models as a function of temperature, and the discrepancies in the results are discussed. Linear equations were fitted to evaluate the influence of temperature on the thermal conductivity of the dairy products. The rheological behavior, specifically apparent viscosity versus shear rate, was influenced by temperature. Herschel-Bulkley, power law, and Newton's law models were used to fit the experimental data. The Herschel-Bulkley model best described the adjustments for yogurt, the power law model did so for fermented dairy beverages, and Newton's law model did so for fermented milk and was then used to determine the rheological parameters. Fermented milk showed a Newtonian trend, whereas yogurt and fermented dairy beverage were shear thinning. Apparent viscosity was correlated with temperature by the Arrhenius equation. The formulation influenced the effective thermal conductivity. The relationship between the 2 properties was established by fixing the temperature and expressing conductivity as a function of apparent viscosity. Thermal conductivity increased with viscosity and decreased with increasing temperature. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

A method for matching the refractive index and kinematic viscosity of a blood analog for flow visualization in hydraulic cardiovascular models.

Science.gov (United States)

Nguyen, T T; Biadillah, Y; Mongrain, R; Brunette, J; Tardif, J C; Bertrand, O F

2004-08-01

In this work, we propose a simple method to simultaneously match the refractive index and kinematic viscosity of a circulating blood analog in hydraulic models for optical flow measurement techniques (PIV, PMFV, LDA, and LIF). The method is based on the determination of the volumetric proportions and temperature at which two transparent miscible liquids should be mixed to reproduce the targeted fluid characteristics. The temperature dependence models are a linear relation for the refractive index and an Arrhenius relation for the dynamic viscosity of each liquid. Then the dynamic viscosity of the mixture is represented with a Grunberg-Nissan model of type 1. Experimental tests for acrylic and blood viscosity were found to be in very good agreement with the targeted values (measured refractive index of 1.486 and kinematic viscosity of 3.454 milli-m2/s with targeted values of 1.47 and 3.300 milli-m2/s).

Design of Oil Viscosity Sensor Based on Plastic Optical Fiber

Science.gov (United States)

Yunus, Muhammad; Arifin, A.

2018-03-01

A research of plastic optical fiber based sensors have been studied for measurement of oil viscosity. This sensor was made with straight configuration, U configuration, and gamma configuration have two types, there are optical fiber sensor with cladding and without cladding. Viscosity sensor was made, dipped into an oil sample with a concentration of viscosity percentage about 270 mPa.s - 350 mPa.s. The light from the LED propagated into the optical fiber, then it was received by the photodetector converted to output power. When plastic optical fiber dipped into an oil sample, viscosity of oil affect increase of refractive index on optical fiber resulting in a bigger loss of power so the light intensity will be smaller, consequences the measured output power will be smaller. Sensitivity and resolution viscosity sensor without cladding peel showed the best result rather than viscosity sensor with cladding peel. The best result in the measurement showed in gamma configuration with 3 cm length of cladding peel and the diameter of bending 0,25 cm is the range 103,090 nWatt, sensitivity 1,289 nWatt/mPa.s, and resolution 0,776 mPa.s. This method is effectively and efficiently used as an oil viscosity sensor with high sensitivity and resolution.

Elongational viscosity of monodisperse and bidisperse polystyrene melts

DEFF Research Database (Denmark)

Nielsen, Jens Kromann; Rasmussen, Henrik Koblitz; Hassager, Ole

2005-01-01

The startup and steady uniaxial elongational viscosity have been measured for two monodisperse polystyrene melts with molecular weights of 52 kg/mole (PS52K) and 103 kg/mole (PS103K), and for three bidisperse polystyrene melts. The bidisperse melts consist of PS103K or PS52K and a monodisperse...... (closed loop proportional regulator) using the laser in such a way that the stretch rate at the neck is kept constant. The rheometer has been described in more detail in (A. Bach, H.K. Rasmussen and O. Hassager, Journal of Rheology, 47 (2003) 429). PS390K show a decrease in the steady viscosity as a power......-law function of the elongational rate (A. Bach, K. Almdal, H.K. Rasmussen and O. Hassager, Macromolecules 36 (2003) 5174). PS52K and PS103K show that the steady viscosity has a maximum that is respectively 100% and 50% above 3 times the zero-shear-rate viscosity. The bidisperse melts show a significant...

Empirical Modeling of the Viscosity of Supercritical Carbon Dioxide Foam Fracturing Fluid under Different Downhole Conditions

Directory of Open Access Journals (Sweden)

Shehzad Ahmed

2018-03-01

Full Text Available High-quality supercritical CO2 (sCO2 foam as a fracturing fluid is considered ideal for fracturing shale gas reservoirs. The apparent viscosity of the fracturing fluid holds an important role and governs the efficiency of the fracturing process. In this study, the viscosity of sCO2 foam and its empirical correlations are presented as a function of temperature, pressure, and shear rate. A series of experiments were performed to investigate the effect of temperature, pressure, and shear rate on the apparent viscosity of sCO2 foam generated by a widely used mixed surfactant system. An advanced high pressure, high temperature (HPHT foam rheometer was used to measure the apparent viscosity of the foam over a wide range of reservoir temperatures (40–120 °C, pressures (1000–2500 psi, and shear rates (10–500 s−1. A well-known power law model was modified to accommodate the individual and combined effect of temperature, pressure, and shear rate on the apparent viscosity of the foam. Flow indices of the power law were found to be a function of temperature, pressure, and shear rate. Nonlinear regression was also performed on the foam apparent viscosity data to develop these correlations. The newly developed correlations provide an accurate prediction of the foam’s apparent viscosity under different fracturing conditions. These correlations can be helpful for evaluating foam-fracturing efficiency by incorporating them into a fracturing simulator.

ANALYSIS OF MARANGONI CONVECTION OF NON-NEWTONIAN POWER LAW FLUIDS WITH LINEAR TEMPERATURE DISTRIBUTION

Directory of Open Access Journals (Sweden)

Yan Zhang

2011-01-01

Full Text Available The problem of steady, laminar, thermal Marangoni convection flow of non-Newtonian power law fluid along a horizontal surface with variable surface temperature is studied. The partial differential equations are transformed into ordinary differential equations by using a suitable similarity transformation and analytical approximate solutions are obtained by an efficient transformation, asymptotic expansion and Padé approximants technique. The effects of power law index and Marangoni number on velocity and temperature profiles are examined and discussed.

Fractional power-law spatial dispersion in electrodynamics

International Nuclear Information System (INIS)

Tarasov, Vasily E.; Trujillo, Juan J.

2013-01-01

Electric fields in non-local media with power-law spatial dispersion are discussed. Equations involving a fractional Laplacian in the Riesz form that describe the electric fields in such non-local media are studied. The generalizations of Coulomb’s law and Debye’s screening for power-law non-local media are characterized. We consider simple models with anomalous behavior of plasma-like media with power-law spatial dispersions. The suggested fractional differential models for these plasma-like media are discussed to describe non-local properties of power-law type. -- Highlights: •Plasma-like non-local media with power-law spatial dispersion. •Fractional differential equations for electric fields in the media. •The generalizations of Coulomb’s law and Debye’s screening for the media

Certain laws governing the influence of high molecular polymer additives on specific electrical conductivity and viscosity of zincate alkaline solution

Energy Technology Data Exchange (ETDEWEB)

Dmitrenko, V.Ye.; Toropetsera, T.N.; Zubov, M.S.

1983-01-01

A study was made of the influence of polymer additives of different nature: polyelectrolyte, copolymer of ethylene with maleic anhydride, polymethacrylic acid and nonpolyectrolyte copolymer of vinyl alcohol with vinyleneglycol and polyvinyleneglycol on specific electrical conductance and viscosity of the zincate alkaline solution. It is indicated that with an increase in the content of additives, the specific conductance of the solution diminishes according to a linear law, while the viscosity rises. The additives of polyelectrolyte nature reduce more strongly the specific conductance and increase the viscosity than the nonpolyelectrolyte additives. From a comparison of the data on specific conductance and viscosity the following conclusion is drawn: the more the polymer ''structures'' the zincate alkaline solution, the more strongly it reduces its specific electrical conductance.

Viscosity in Modified Gravity 

Directory of Open Access Journals (Sweden)

Iver Brevik

2012-11-01

Full Text Available A bulk viscosity is introduced in the formalism of modified gravity. It is shownthat, based on a natural scaling law for the viscosity, a simple solution can be found forquantities such as the Hubble parameter and the energy density. These solutions mayincorporate a viscosity-induced Big Rip singularity. By introducing a phase transition inthe cosmic fluid, the future singularity can nevertheless in principle be avoided. 

MHD free convection flow of a non-Newtonian power-law fluid over ...

African Journals Online (AJOL)

... flow have been presented for various parameters such as Prandtl number, flow behavior index (n), porous plate parameter and magnetic parameter. The local Nusselt number and skin friction coefficient is also presented graphically. Keywords: Magnetohydrodynamic flow; free convection flow; Non-Newtonian power-law

Quantum dissipation from power-law memory

International Nuclear Information System (INIS)

Tarasov, Vasily E.

2012-01-01

A new quantum dissipation model based on memory mechanism is suggested. Dynamics of open and closed quantum systems with power-law memory is considered. The processes with power-law memory are described by using integration and differentiation of non-integer orders, by methods of fractional calculus. An example of quantum oscillator with linear friction and power-law memory is considered. - Highlights: ► A new quantum dissipation model based on memory mechanism is suggested. ► The generalization of Lindblad equation is considered. ► An exact solution of generalized Lindblad equation for quantum oscillator with linear friction and power-law memory is derived.

Power law scaling in synchronization of brain signals depends on cognitive load

Directory of Open Access Journals (Sweden)

Jose Luis ePerez Velazquez

2014-05-01

Full Text Available As it has several features that optimize information processing, it has been proposed that criticality governs the dynamics of nervous system activity. Indications of such dynamics have been reported for a variety of in vitro and in vivo recordings, ranging from in vitro slice electrophysiology to human functional magnetic resonance imaging. However, there still remains considerable debate as to whether the brain actually operates close to criticality or in another governing state such as stochastic or oscillatory dynamics. A tool used to investigate the criticality of nervous system data is the inspection of power-law distributions. Although the findings are controversial, such power-law scaling has been found in different types of recordings. Here, we studied whether there is a power law scaling in the distribution of the phase synchronization derived from magnetoencephalographic recordings during executive function tasks performed by children with and without autism. Characterizing the brain dynamics that is different between autistic and non-autistic individuals is important in order to find differences that could either aid diagnosis or provide insights as to possible therapeutic interventions in autism. We report in this study that power law scaling in the distributions of a phase synchrony index is not very common and its frequency of occurrence is similar in the control and the autism group. In addition, power law scaling tends to diminish with increased cognitive load (difficulty or engagement in the task. There were indications of changes in the probability distribution functions for the phase synchrony that were associated with a transition from power law scaling to lack of power law (or vice versa, which suggests the presence of phenomenological bifurcations in brain dynamics associated with cognitive load. Hence, brain dynamics may fluctuate between criticality and other regimes depending upon context and behaviours.

Zipf's law, power laws and maximum entropy

International Nuclear Information System (INIS)

Visser, Matt

2013-01-01

Zipf's law, and power laws in general, have attracted and continue to attract considerable attention in a wide variety of disciplines—from astronomy to demographics to software structure to economics to linguistics to zoology, and even warfare. A recent model of random group formation (RGF) attempts a general explanation of such phenomena based on Jaynes' notion of maximum entropy applied to a particular choice of cost function. In the present paper I argue that the specific cost function used in the RGF model is in fact unnecessarily complicated, and that power laws can be obtained in a much simpler way by applying maximum entropy ideas directly to the Shannon entropy subject only to a single constraint: that the average of the logarithm of the observable quantity is specified. (paper)

Power Laws are Disguised Boltzmann Laws

Science.gov (United States)

Richmond, Peter; Solomon, Sorin

Using a previously introduced model on generalized Lotka-Volterra dynamics together with some recent results for the solution of generalized Langevin equations, we derive analytically the equilibrium mean field solution for the probability distribution of wealth and show that it has two characteristic regimes. For large values of wealth, it takes the form of a Pareto style power law. For small values of wealth, wGeneralized Lotka-Volterra type of stochastic dynamics. The power law that arises in the distribution function is identified with new additional logarithmic terms in the familiar Boltzmann distribution function for the system. These are a direct consequence of the multiplicative stochastic dynamics and are absent for the usual additive stochastic processes.

Study of specific loss power of magnetic fluids with various viscosities

Energy Technology Data Exchange (ETDEWEB)

Phong, P.T., E-mail: phamthanhphong@tdt.edu.vn [Department for Management of Science and Technology Development, Ton Duc Thang University, Ho Chi Minh City (Viet Nam); Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City (Viet Nam); Nguyen, L.H., E-mail: luuhuunguyen@ukh.edu.vn [Institute of Materials Science, Vietnam Academy of Science and Technology,18- Hoang Quoc Viet Street, Cau Giay District, Ha Noi City (Viet Nam); Khanh Hoa University, 1- Nguyen Chanh Street, Nha Trang City, Khanh Hoa Province (Viet Nam); Phong, L.T.H., E-mail: lthp52a@gmail.com [Institute of Materials Science, Vietnam Academy of Science and Technology,18- Hoang Quoc Viet Street, Cau Giay District, Ha Noi City (Viet Nam); Nam, P.H., E-mail: namph.ims@gmail.com [Institute of Materials Science, Vietnam Academy of Science and Technology,18- Hoang Quoc Viet Street, Cau Giay District, Ha Noi City (Viet Nam); Manh, D.H., E-mail: manhdh.ims@gmail.com [Institute of Materials Science, Vietnam Academy of Science and Technology,18- Hoang Quoc Viet Street, Cau Giay District, Ha Noi City (Viet Nam); Lee, I.J., E-mail: lij@dongguk.ac.kr [Department of Advanced Materials Chemistry, Dongguk University-Gyeongju, Dongdae-roDongdae-ro 123, Gyeongju-Si, Gyeongbuk 38066 (Korea, Republic of); Phuc, N.X., E-mail: phucnx1949@gmail.com [Institute of Materials Science, Vietnam Academy of Science and Technology,18- Hoang Quoc Viet Street, Cau Giay District, Ha Noi City (Viet Nam)

2017-04-15

Abstracts: Using hydrothermal method, CoFe{sub 2}O{sub 4} (hard ferrite) and MnFe{sub 2}O{sub 4} (soft ferrite) nanoparticles of size up to 20 nm were synthesized and the viscosities were controlled using various concentrations of agar. The hydrodynamic diameter of these particles was measured and fitted to a lognormal distribution and the results showed their polydispersity is very narrow. From the calorimetric measurements of the particles stabilized in agar solutions, we have demonstrated that at a given frequency, the dependence of the specific loss power of magnetic fluids on the viscosity is in good agreement with the theoretical predictions made in the earlier studies. - Highlights: • CoFe{sub 2}O{sub 4} (hard ferrite) and MnFe{sub 2}O{sub 4} (soft ferrite) nanoparticles size up to 20 nm were synthesized. • The relaxation loss depends on both the particle's intrinsic properties and the viscosity of the environment. • The SLP of hard nanoparticles strongly decreases with increasing the viscosity whereas that of soft nanoparticles remains almost unchanged.

Graph Structure in Three National Academic Webs: Power Laws with Anomalies.

Science.gov (United States)

Thelwall, Mike; Wilkinson, David

2003-01-01

Explains how the Web can be modeled as a mathematical graph and analyzes the graph structures of three national university publicly indexable Web sites from Australia, New Zealand, and the United Kingdom. Topics include commercial search engines and academic Web link research; method-analysis environment and data sets; and power laws. (LRW)

Buoyancy limits on magnetic viscosity stress-law scalings in quasi stellar object accretion disk models

International Nuclear Information System (INIS)

Sakimoto, P.J.

1985-01-01

Quasi-Stellar Objects (QSOs) are apparently the excessively bright nuclei of distant galaxies. They are thought to be powered by accretion disks surrounding supermassive black holes: however, proof of this presumption is hampered by major uncertainties in the viscous stress necessary for accretion to occur. Models generally assume an and hoc stress law which scales the stress with the total pressure. Near the black hole, radiation pressure dominates gas pressure; scaling the stress with the radiation pressure results in disk models that are thermally unstable and optically thin. This dissertation shows that a radiation pressure scaling for the stress is not possible if the viscosity is due to turbulent magnetic Maxwell stresses. The argument is one of internal self-consistency. First, four model accretion disks that bound the reasonably expected ranges of viscous stress scalings and vertical structures are constructed. Magnetic flux tubes of various initial field strengths are then placed within these models, nd their buoyancy is modeled numerically. In disks using the radiation pressure stress law scaling, low opacities allow rapid heat flow into the flux tubes: the tubes are extremely buoyant, and magnetic fields strong enough to provide the required stress cannot be retained. If an alternative gas pressure scaling for the stress is assumed, then the disks are optically thick; flux tubes have corresponding lower buoyancy, and magnetic fields strong enough to provide the stress can be retained for dynamically significant time periods

Stochastic model of Zipf's law and the universality of the power-law exponent.

Science.gov (United States)

Yamamoto, Ken

2014-04-01

We propose a stochastic model of Zipf's law, namely a power-law relation between rank and size, and clarify as to why a specific value of its power-law exponent is quite universal. We focus on the successive total of a multiplicative stochastic process. By employing properties of a well-known stochastic process, we concisely show that the successive total follows a stationary power-law distribution, which is directly related to Zipf's law. The formula of the power-law exponent is also derived. Finally, we conclude that the universality of the rank-size exponent is brought about by symmetry between an increase and a decrease in the random growth rate.

Power laws in Ising nanostripes

International Nuclear Information System (INIS)

Drzewinski, A.; Sznajd, J.; Szota, K.

2005-01-01

The results of high accuracy density-matrix renormalization-group calculations for infinite Ising stripes of finite widths 100 ≤ L ≤ 400 are presented. It is shown that in the presence of the small external magnetic field the infinite system critical power laws can be observed for L of order hundreds nm. The single power law describes the field dependence of the magnetization or the longitudinal correlation length only on the infinite system critical isotherm independently of the value of L. The approximate power law which describes how the magnetization varies with a distance from the infinite system critical point for several directions in the plane (temperature, external field) is also studied. (author)

Excess molar volume along with viscosity, refractive index and relative permittivity for binary mixtures of exo-tetrahydrodicyclopentadiene with four octane isomers

International Nuclear Information System (INIS)

Yue, Lei; Qin, Xiaomei; Wu, Xi; Xu, Li; Guo, Yongsheng; Fang, Wenjun

2015-01-01

Highlights: • Binary mixtures of JP-10 with octane isomers are studied as model hydrocarbon fuels. • Density, viscosity, refractive index and relative permittivity are determined. • Excess molar volumes and viscosity deviations are calculated and correlated. - Abstract: The fundamental physical properties including density, viscosity, refractive index and relative permittivity, have been measured for binary mixtures of exo-tetrahydrodicyclopentadiene (JP-10) with four octane isomers (n-octane, 3-methylheptane, 2,4-dimethylhexane and 2,2,4-trimethylpentane) over the whole composition range at temperatures T = (293.15 to 313.15) K and pressure p = 0.1 MPa. The values of excess molar volume (V m E ), viscosity deviation (Δη), refractive index deviation (Δn D ) and relative permittivity deviation (Δε r ) are then calculated. All of the values of V m E and Δη are observed to be negative, while those of Δn D and Δε r are close to zero. The effects of temperature and composition on the variation of V m E values are discussed. The negative values of V m E and Δη are conductive to high-density and low-resistance of fuels, which is favorable for the design and preparation of advanced hydrocarbon fuels

On heat transfer of weakly compressible power-law flows

Directory of Open Access Journals (Sweden)

Li Botong

2017-01-01

Full Text Available This paper completes a numerical research on steady momentum and heat transfer in power-law fluids in a channel. Weakly compressible laminar fluids are studied with no slip at the walls and uniform wall temperatures. The full governing equations are solved by continuous finite element method. Three thermal conductivity models are adopted in this paper, that is, constant thermal conductivity model, thermal conductivity varying as a function of temperature gradient, and a modified temperature-gradient-dependent thermal conductivity model. The results are compared with each other and the physical characteristics for values of parameters are also discussed in details. It is shown that the velocity curve from the solution becomes straight at higher power-law index. The effects of Reynolds numbers on the dilatant fluid and the pseudo-plastic look similar to each other and their trends can be easily predicted. Furthermore, for different models, the temperature curves also present pseudo-plastic and dilatant properties.

Power law deformation of Wishart–Laguerre ensembles of random matrices

International Nuclear Information System (INIS)

Akemann, Gernot; Vivo, Pierpaolo

2008-01-01

We introduce a one-parameter deformation of the Wishart–Laguerre or chiral ensembles of positive definite random matrices with Dyson index β = 1,2 and 4. Our generalized model has a fat-tailed distribution while preserving the invariance under orthogonal, unitary or symplectic transformations. The spectral properties are derived analytically for finite matrix size N × M for all three values of β, in terms of the orthogonal polynomials of the standard Wishart–Laguerre ensembles. For large N in a certain double-scaling limit we obtain a generalized Marčenko–Pastur distribution on the macroscopic scale, and a generalized Bessel law at the hard edge which is shown to be universal. Both macroscopic and microscopic correlations exhibit power law tails, where the microscopic limit depends on β and the difference M−N. In the limit where our parameter governing the power law goes to infinity we recover the correlations of the Wishart–Laguerre ensembles. To illustrate these findings, the generalized Marčenko–Pastur distribution is shown to be in very good agreement with empirical data from financial covariance matrices

Thermodynamic study of three pharmacologically significant drugs: Density, viscosity, and refractive index measurements at different temperatures

International Nuclear Information System (INIS)

Iqbal, Muhammad Javed; Chaudhry, Mansoora Ahmed

2009-01-01

Measurements of density, viscosity, and refractive index of three pharmacologically significant drugs, i.e. diclofenac sodium, cetrizine, and doxycycline have been carried in aqueous medium at T = (293.15 to 313.15) K. An automated vibrating-tube densimeter, viscometer, and refractometer are used in a concentration range from (7.5) . 10 -3 to 25 . 10 -3 ) mol . kg -1 . The precise density results are used to evaluate the apparent molar volume, partial molar volume, thermal expansion coefficient, partial molar expansivity, and the Hepler's constant. Viscosity results are used to calculate the Jones-Dole viscosity B-coefficient, free energy of activation of the solute and solvent, activation enthalpy, and activation entropy. The molar refractive indices of the drug solutions can be employed to calculate molar refraction. It is inferred from these results that the above mentioned drugs act as structure-making compounds due to hydrophobic hydration of the molecules in the drugs

Coffee Index as Quick and Simple Indicator of Purchasing Power Parity

Directory of Open Access Journals (Sweden)

Jakub Fischer

2018-03-01

Full Text Available Purchasing Power Parity is the corner stone of all international comparisons. Various approaches to Purchasing Power Parity, such as the Big Mac Index, KFC Index, iPad Index, Tall Latte Index or Ikea Index were popularized to the broader audience besides the OECD Purchasing Power Parity indices. The aim of this paper is to develop a new ready-to-use quick and simple index based on the prices of Nespresso coffee’s capsules and show the main challenges of such indices as well as of the PPP concept. For the purpose of our research the data on the Nespresso capsules prices were collected. Taking into account also the popularity (demand side of the capsules types, the Espresso line was chosen as the basis for which all further calculations are made. The Nespresso Index provides us with clear evidence that the Law of One Price cannot work in recent world because of three key features. Firstly, differences in taxes make the perfect parity impossible. Secondly, the price discrimination prevents the rational subjects from arbitrage. Finally, the changes in the exchange rate make such indices highly volatile. Despite these weaknesses, the Nespresso Index could be used as the useful supplement of the OECD PPP as it is low cost, easy and fast to compute and digestible for the lay public.

Power laws in citation distributions: evidence from Scopus.

Science.gov (United States)

Brzezinski, Michal

Modeling distributions of citations to scientific papers is crucial for understanding how science develops. However, there is a considerable empirical controversy on which statistical model fits the citation distributions best. This paper is concerned with rigorous empirical detection of power-law behaviour in the distribution of citations received by the most highly cited scientific papers. We have used a large, novel data set on citations to scientific papers published between 1998 and 2002 drawn from Scopus. The power-law model is compared with a number of alternative models using a likelihood ratio test. We have found that the power-law hypothesis is rejected for around half of the Scopus fields of science. For these fields of science, the Yule, power-law with exponential cut-off and log-normal distributions seem to fit the data better than the pure power-law model. On the other hand, when the power-law hypothesis is not rejected, it is usually empirically indistinguishable from most of the alternative models. The pure power-law model seems to be the best model only for the most highly cited papers in "Physics and Astronomy". Overall, our results seem to support theories implying that the most highly cited scientific papers follow the Yule, power-law with exponential cut-off or log-normal distribution. Our findings suggest also that power laws in citation distributions, when present, account only for a very small fraction of the published papers (less than 1 % for most of science fields) and that the power-law scaling parameter (exponent) is substantially higher (from around 3.2 to around 4.7) than found in the older literature.

Accuracy analysis of measurements on a stable power-law distributed series of events

International Nuclear Information System (INIS)

Matthews, J O; Hopcraft, K I; Jakeman, E; Siviour, G B

2006-01-01

We investigate how finite measurement time limits the accuracy with which the parameters of a stably distributed random series of events can be determined. The model process is generated by timing the emigration of individuals from a population that is subject to deaths and a particular choice of multiple immigration events. This leads to a scale-free discrete random process where customary measures, such as mean value and variance, do not exist. However, converting the number of events occurring in fixed time intervals to a 1-bit 'clipped' process allows the construction of well-behaved statistics that still retain vestiges of the original power-law and fluctuation properties. These statistics include the clipped mean and correlation function, from measurements of which both the power-law index of the distribution of events and the time constant of its fluctuations can be deduced. We report here a theoretical analysis of the accuracy of measurements of the mean of the clipped process. This indicates that, for a fixed experiment time, the error on measurements of the sample mean is minimized by an optimum choice of the number of samples. It is shown furthermore that this choice is sensitive to the power-law index and that the approach to Poisson statistics is dominated by rare events or 'outliers'. Our results are supported by numerical simulation

Resurrecting the Power-law, Intermediate, and Logamediate Inflations in the DBI Scenario with Constant Sound Speed

Science.gov (United States)

Amani, Roonak; Rezazadeh, Kazem; Abdolmaleki, Asrin; Karami, Kayoomars

2018-02-01

We investigate the power-law, intermediate, and logamediate inflationary models in the framework of DBI non-canonical scalar field with constant sound speed. In the DBI setting, we first represent the power spectrum of both scalar density and tensor gravitational perturbations. Then, we derive different inflationary observables including the scalar spectral index n s , the running of the scalar spectral index {{dn}}s/d{ln}k, and the tensor-to-scalar ratio r. We show that the 95% CL constraint of the Planck 2015 T + E data on the non-Gaussianity parameter {f}{NL}{DBI} leads to the sound speed bound {c}s≥slant 0.087 in the DBI inflation. Moreover, our results imply that, although the predictions of the power-law, intermediate, and logamediate inflations in the standard canonical framework (c s = 1) are not consistent with the Planck 2015 data, in the DBI scenario with constant sound speed {c}srunning of the scalar spectral index and find that it is compatible with the 95% CL constraint from the Planck 2015 TT,TE,EE+lowP data.

Thermodynamic study of three pharmacologically significant drugs: Density, viscosity, and refractive index measurements at different temperatures

Energy Technology Data Exchange (ETDEWEB)

Iqbal, Muhammad Javed [Department of Chemistry, Quaid-i-Azam University, Islamabad 45320 (Pakistan)], E-mail: mjiqauchem@yahoo.com; Chaudhry, Mansoora Ahmed [Department of Chemistry, Quaid-i-Azam University, Islamabad 45320 (Pakistan)

2009-02-15

Measurements of density, viscosity, and refractive index of three pharmacologically significant drugs, i.e. diclofenac sodium, cetrizine, and doxycycline have been carried in aqueous medium at T = (293.15 to 313.15) K. An automated vibrating-tube densimeter, viscometer, and refractometer are used in a concentration range from (7.5) . 10{sup -3} to 25 . 10{sup -3}) mol . kg{sup -1}. The precise density results are used to evaluate the apparent molar volume, partial molar volume, thermal expansion coefficient, partial molar expansivity, and the Hepler's constant. Viscosity results are used to calculate the Jones-Dole viscosity B-coefficient, free energy of activation of the solute and solvent, activation enthalpy, and activation entropy. The molar refractive indices of the drug solutions can be employed to calculate molar refraction. It is inferred from these results that the above mentioned drugs act as structure-making compounds due to hydrophobic hydration of the molecules in the drugs.

The Transient Elliptic Flow of Power-Law Fluid in Fractal Porous Media

Institute of Scientific and Technical Information of China (English)

宋付权; 刘慈群

2002-01-01

The steady oil production and pressure distribution formulae of vertically fractured well for power-law non-Newtonian fluid were derived on the basis of the elliptic flow model in fractal reservoirs. The corresponding transient flow in fractal reservoirs was studied by numerical differentiation method: the influence of fractal index to transient pressure of vertically fractured well was analyzed. Finally the approximate analytical solution of transient flow was given by average mass conservation law. The study shows that using elliptic flow method to analyze the flow of vertically fractured well is a simple method.

Power-Law Template for IR Point Source Clustering

Science.gov (United States)

Addison, Graeme E.; Dunkley, Joanna; Hajian, Amir; Viero, Marco; Bond, J. Richard; Das, Sudeep; Devlin, Mark; Halpern, Mark; Hincks, Adam; Hlozek, Renee;

Power-Law Template for Infrared Point-Source Clustering

Science.gov (United States)

Addison, Graeme E; Dunkley, Joanna; Hajian, Amir; Viero, Marco; Bond, J. Richard; Das, Sudeep; Devlin, Mark J.; Halpern, Mark; Hincks, Adam D; Hlozek, Renee;

Power law scaling for rotational energy transfer

International Nuclear Information System (INIS)

Pritchard, D.E.; Smith, N.; Driver, R.D.; Brunner, T.A.

1979-01-01

We have applied a new scaling law to several sets of rotational energy transfer cross sections. The new law asserts that the square of the T-matrix depends on the amount of energy transferred as a power law. Two different kinds of angular momentum statistics are assumed, one corresponding to m/sub j/ being conserved and the other corresponding to m/sub j/ being completely randomized. Numerical fits are presented which demonstrate that the data follow the power law better than the widely used exponential gap law

The quick convolution of galaxy profiles, with application to power-law intensity distributions

International Nuclear Information System (INIS)

Bailey, M.E.; Sparks, W.B.

1983-01-01

The two-dimensional convolution of a circularly symmetric galaxy model with a Gaussian point-spread function of dispersion σ reduces to a single integral. This is solved analytically for models with power-law intensity distributions and results are given which relate the apparent core radius to σ and the power-law index k. The convolution integral is also simplified for the case of a point-spread function corresponding to a circular aperture. Models of galactic nuclei with stellar density cusps can only be distinguished from alternatives with small core radii if both the brightness and seeing profiles are measured accurately. The results are applied to data on the light distribution at the Galactic Centre. (author)

Visiting Power Laws in Cyber-Physical Networking Systems

Directory of Open Access Journals (Sweden)

Ming Li

2012-01-01

Full Text Available Cyber-physical networking systems (CPNSs are made up of various physical systems that are heterogeneous in nature. Therefore, exploring universalities in CPNSs for either data or systems is desired in its fundamental theory. This paper is in the aspect of data, aiming at addressing that power laws may yet be a universality of data in CPNSs. The contributions of this paper are in triple folds. First, we provide a short tutorial about power laws. Then, we address the power laws related to some physical systems. Finally, we discuss that power-law-type data may be governed by stochastically differential equations of fractional order. As a side product, we present the point of view that the upper bound of data flow at large-time scaling and the small one also follows power laws.

Helmholtz solitons in power-law optical materials

International Nuclear Information System (INIS)

Christian, J. M.; McDonald, G. S.; Potton, R. J.; Chamorro-Posada, P.

2007-01-01

A nonlinear Helmholtz equation for optical materials with regimes of power-law type of nonlinearity is proposed. This model captures the evolution of broad beams at any angle with respect to the reference direction in a wide range of media, including some semiconductors, doped glasses, and liquid crystals. Exact analytical soliton solutions are presented for a generic nonlinearity, within which known Kerr solitons comprise a subset. Three general conservation laws are also reported. Analysis and numerical simulations examine the stability of the Helmholtz power-law solitons. A propagation feature, associated with spatial solitons in power-law media, constituting a class of oscillatory solution, is identified

Power series like relation of power law and coupled creep ...

African Journals Online (AJOL)

When a solid deforms at high temperature its microstructure may in some sense be altered- holes and cracks may nucleate and grow inside the solid by various mechanism controlled by diffusion and by power law creep or by a combination of these mechanisms. Considering a coupled diffusion power law creep mechanism ...

The speed-curvature power law of movements: a reappraisal.

Science.gov (United States)

Zago, Myrka; Matic, Adam; Flash, Tamar; Gomez-Marin, Alex; Lacquaniti, Francesco

2018-01-01

Several types of curvilinear movements obey approximately the so called 2/3 power law, according to which the angular speed varies proportionally to the 2/3 power of the curvature. The origin of the law is debated but it is generally thought to depend on physiological mechanisms. However, a recent paper (Marken and Shaffer, Exp Brain Res 88:685-690, 2017) claims that this power law is simply a statistical artifact, being a mathematical consequence of the way speed and curvature are calculated. Here we reject this hypothesis by showing that the speed-curvature power law of biological movements is non-trivial. First, we confirm that the power exponent varies with the shape of human drawing movements and with environmental factors. Second, we report experimental data from Drosophila larvae demonstrating that the power law does not depend on how curvature is calculated. Third, we prove that the law can be violated by means of several mathematical and physical examples. Finally, we discuss biological constraints that may underlie speed-curvature power laws discovered in empirical studies.

Power-law-lapse time gauges

International Nuclear Information System (INIS)

Jantzen, R.T.

1988-01-01

The choice of time function for cosmological solutions of gravitational field equations is related to the action of the group of independent scale transformations of the unit of length along orthogonal spatial directions. This is accomplished by the introduction of lapse functions which depend explicitly on the spatial metric in an appropriately defined power-law fashion. The resulting power-law-lapse time gauges are the key to producing nearly all exact solutions of the class of models for which the field equations reduce to ordinary differential equations

Viscosity and Analytical Differences between Raw Milk and UHT Milk of Czech Cows

Directory of Open Access Journals (Sweden)

Kumbár V.

2015-06-01

Full Text Available Viscosity and analytical differences in four milk samples from Czech cows were described. Three samples of UHT milk (0.5%, 1.5%, and 3.5% fat and one sample of raw milk from a Czech bio-farm were analyzed. The following analytical properties were observed: titratable acidity, fat content, dry matter content, and protein content. Titratable acidity and dry matter content decreased in dependence upon the increasing milk fat content. The protein content ranged 3.51-3.57 g per 100 g milk. The milk flow behaviour represented by density, dynamic and kinematic viscosity, as well as the dependence of the milk flow behaviour on temperature were investigated. These properties were measured using a digital densitometer and a rotary viscometer. Milk density was studied at temperatures ranging 0-60 °C and dynamic viscosity at 0-100 °C. With increasing temperature, the density and dynamic viscosity of the studied milk samples decreased. The temperature dependence of dynamic viscosity was manifested in all samples. Kinematic viscosity was calculated from experimental data. Furthermore, mathematical models using Power law and Gaussian fitting were constructed. Determination coefficients achieved high values (0.843-0.997.

Viscosity effect in Landau's hydrodynamical model

International Nuclear Information System (INIS)

Hoang, T.F.; Phua, K.K.; Nanyang Univ., Singapore

1979-01-01

The Bose-Einstein distribution is used to investigate Landau's hydrodynamical model with viscosity. In case the viscosity dependence on the temperature is T 3 , the correction to the multiplicity behaves like I/E and is found to be negligible for the pp data. A discussion is presented on a possibility of reconciling E 1 / 2 and logE dependence of the multiplicity law. (orig.)

Barkhausen jumps and magnetic viscosity in NdFeB magnets

Energy Technology Data Exchange (ETDEWEB)

LoBue, M. [Instituto Elettrotecnico Nazionale Galileo Ferraris, Strada delle Cacce 91, 10135 Torino (Italy)]. E-mail: lobue@ien.it; Basso, V. [Instituto Elettrotecnico Nazionale Galileo Ferraris, Strada delle Cacce 91, 10135 Torino (Italy); Beatrice, G. [Instituto Elettrotecnico Nazionale Galileo Ferraris, Strada delle Cacce 91, 10135 Torino (Italy); Bertotti, C. [Instituto Elettrotecnico Nazionale Galileo Ferraris, Strada delle Cacce 91, 10135 Torino (Italy); Durin, G. [Instituto Elettrotecnico Nazionale Galileo Ferraris, Strada delle Cacce 91, 10135 Torino (Italy); Sasso, C.P. [Instituto Elettrotecnico Nazionale Galileo Ferraris, Strada delle Cacce 91, 10135 Torino (Italy)

2005-04-15

We present the analysis of Barkhausen noise measured on a Nd-Fe-B sintered sample during viscosity experiments at constant applied field H. The measured jump sizes give direct evidence that the dominant magnetization process is the reversal of a single or of a small group of grains. The Barkhausen noise average amplitude allows to evaluate the viscosity coefficient S and the related activation volume v{sub a}. We found v{sub a}{sup 1/3} {approx} 6nm which is comparable to the domain wall width, in agreement with previous interpretations. The Barkhausen jump sizes show a power-law distribution independent of the time elapsed from the beginning of the relaxation. This fact validates the interpretation of the observed relaxations as due to thermal activation over a distribution of energy barriers.

Barkhausen jumps and magnetic viscosity in NdFeB magnets

International Nuclear Information System (INIS)

LoBue, M.; Basso, V.; Beatrice, G.; Bertotti, C.; Durin, G.; Sasso, C.P.

2005-01-01

We present the analysis of Barkhausen noise measured on a Nd-Fe-B sintered sample during viscosity experiments at constant applied field H. The measured jump sizes give direct evidence that the dominant magnetization process is the reversal of a single or of a small group of grains. The Barkhausen noise average amplitude allows to evaluate the viscosity coefficient S and the related activation volume v a . We found v a 1/3 ∼ 6nm which is comparable to the domain wall width, in agreement with previous interpretations. The Barkhausen jump sizes show a power-law distribution independent of the time elapsed from the beginning of the relaxation. This fact validates the interpretation of the observed relaxations as due to thermal activation over a distribution of energy barriers

Non-Darcy Free Convection of Power-Law Fluids Over a Two-Dimensional Body Embedded in a Porous Medium

KAUST Repository

El-Amin, Mohamed

2010-11-27

A boundary layer analysis was presented to study the non-Darcy-free convection of a power-law fluid over a non-isothermal two-dimensional body embedded in a porous medium. The Ostwald-de Waele power-law model was used to characterize the non-Newtonian fluid behavior. Similarity solutions were obtained with variations in surface temperature or surface heat flux. In view of the fact that most of the non-Newtonian fluids have large Prandtl numbers, this study was directed toward such fluids. The effects of the porous medium parameters, k1 and k2, body shape parameter, m, and surface thermal variations parameter, p, as well as the power-law index, n, were examined. © 2010 Springer Science+Business Media B.V.

Non-Darcy Free Convection of Power-Law Fluids Over a Two-Dimensional Body Embedded in a Porous Medium

KAUST Repository

El-Amin, Mohamed; Sun, Shuyu; El-Ameen, M. A.; Jaha, Y. A.; Gorla, Rama Subba Reddy

2010-01-01

A boundary layer analysis was presented to study the non-Darcy-free convection of a power-law fluid over a non-isothermal two-dimensional body embedded in a porous medium. The Ostwald-de Waele power-law model was used to characterize the non-Newtonian fluid behavior. Similarity solutions were obtained with variations in surface temperature or surface heat flux. In view of the fact that most of the non-Newtonian fluids have large Prandtl numbers, this study was directed toward such fluids. The effects of the porous medium parameters, k1 and k2, body shape parameter, m, and surface thermal variations parameter, p, as well as the power-law index, n, were examined. © 2010 Springer Science+Business Media B.V.

Viscosity measurements on metal melts at high pressure and viscosity calculations for the earth's core

International Nuclear Information System (INIS)

Mineev, Vladimir N; Funtikov, Aleksandr I

2004-01-01

A review is given of experimental and calculated data on the viscosity of iron-based melts on the melting curve. The interest in these data originates in the division of opinion on whether viscosity increases rather moderately or considerably in the high-pressure range. This disagreement is especially pronounced in the interpretation of the values of molten iron and its compounds in the environment of the earth's outer core. The conclusion on a substantial rise in viscosity mostly follows from the universal law, proposed by Brazhkin and Lyapin [1], of viscosity changing along the metal melting curve in the high-pressure range. The review analyzes available experimental and computational data, including the most recent ones. Data on viscosity of metals under shock wave compression in the megabar pressure range are also discussed. It is shown that data on viscosity of metal melts point to a small increase of viscosity on the melting curve. Specifics are discussed of the phase diagram of iron made more complex by the presence of several phase transitions and by the uncertainty in the position of the melting curve in the high-pressure range. Inaccuracies that arise in extrapolating the results of viscosity measurements to the pressure range corresponding to the earth's core environment are pointed out. (reviews of topical problems)

Convergence of a residual based artificial viscosity finite element method

KAUST Repository

Nazarov, Murtazo

2013-02-01

We present a residual based artificial viscosity finite element method to solve conservation laws. The Galerkin approximation is stabilized by only residual based artificial viscosity, without any least-squares, SUPG, or streamline diffusion terms. We prove convergence of the method, applied to a scalar conservation law in two space dimensions, toward an unique entropy solution for implicit time stepping schemes. © 2012 Elsevier B.V. All rights reserved.

Scaling laws for fractional Brownian motion with power-law clock

International Nuclear Information System (INIS)

O'Malley, Daniel; Cushman, John H; Johnson, Graham

2011-01-01

We study the mean first passage time (MFPT) for fractional Brownian motion (fBm) in a finite interval with absorbing boundaries at each end. Analytical arguments are used to suggest a simple scaling law for the MFPT and numerical experiments are performed to verify its accuracy. The same approach is used to derive a scaling law for fBm with a power-law clock (fBm-plc). The MFPT scaling laws are employed to develop scaling laws for the finite-size Lyapunov exponent (FSLE) of fBm and fBm-plc. We apply these results to diffusion of a large polymer in a region with absorbing boundaries. (letter)

Automated image enhancement using power law transformations

Indian Academy of Sciences (India)

We propose a scheme for automating power law transformations which are used for image enhancement. The scheme we propose does not require the user to choose the exponent in the power law transformation. This method works well for images having poor contrast, especially to those images in which the peaks ...

Power-law versus log-law in wall-bounded turbulence: A large-eddy simulation perspective

Science.gov (United States)

Cheng, W.; Samtaney, R.

2014-01-01

The debate whether the mean streamwise velocity in wall-bounded turbulent flows obeys a log-law or a power-law scaling originated over two decades ago, and continues to ferment in recent years. As experiments and direct numerical simulation can not provide sufficient clues, in this study we present an insight into this debate from a large-eddy simulation (LES) viewpoint. The LES organically combines state-of-the-art models (the stretched-vortex model and inflow rescaling method) with a virtual-wall model derived under different scaling law assumptions (the log-law or the power-law by George and Castillo ["Zero-pressure-gradient turbulent boundary layer," Appl. Mech. Rev. 50, 689 (1997)]). Comparison of LES results for Reθ ranging from 105 to 1011 for zero-pressure-gradient turbulent boundary layer flows are carried out for the mean streamwise velocity, its gradient and its scaled gradient. Our results provide strong evidence that for both sets of modeling assumption (log law or power law), the turbulence gravitates naturally towards the log-law scaling at extremely large Reynolds numbers.

Power-law versus log-law in wall-bounded turbulence: A large-eddy simulation perspective

KAUST Repository

Cheng, W.

2014-01-29

The debate whether the mean streamwise velocity in wall-bounded turbulent flows obeys a log-law or a power-law scaling originated over two decades ago, and continues to ferment in recent years. As experiments and direct numerical simulation can not provide sufficient clues, in this study we present an insight into this debate from a large-eddy simulation (LES) viewpoint. The LES organically combines state-of-the-art models (the stretched-vortex model and inflow rescaling method) with a virtual-wall model derived under different scaling law assumptions (the log-law or the power-law by George and Castillo [“Zero-pressure-gradient turbulent boundary layer,” Appl. Mech. Rev.50, 689 (1997)]). Comparison of LES results for Re θ ranging from 105 to 1011 for zero-pressure-gradient turbulent boundary layer flows are carried out for the mean streamwise velocity, its gradient and its scaled gradient. Our results provide strong evidence that for both sets of modeling assumption (log law or power law), the turbulence gravitates naturally towards the log-law scaling at extremely large Reynolds numbers.

Power laws in the information production process Lotkaian informetrics

CERN Document Server

Egghe, Leo

2005-01-01

Explains many informetric regularities, only based on a decreasing power law as size-frequency function, that is Lotka''s law. This book revives the historical formulation of Alfred Lotka and shows the power of this power law, both in classical aspects of informetrics as well as in applications such as social networks and others.

Numerical analysis of the transient conjugated heat transfer in a circular duct with a power-law fluid

Energy Technology Data Exchange (ETDEWEB)

Luna, N. [Secretaria de Energia, Direccion de Operacion Petrolera, Mexico DF (Mexico); Mendez, F. [UNAM, Facultad de Ingenieria, Mexico DF (Mexico); Bautista, O. [ITESM, Division de Ingenieria y Arquitectura, Mexico DF (Mexico)

2005-05-01

We treat numerically in this paper, the transient analysis of a conjugated heat transfer process in the thermal entrance region of a circular tube with a fully developed laminar power-law fluid flow. We apply the quasi-steady approximation for the power-law fluid, identifying the suitable time scales of the process. Thus, the energy equation in the fluids is solved analytically using the well-known integral boundary layer technique. This solution is coupled to the transient energy equation for the solid where the transverse and longitudinal heat conduction effects are taken into account. The numerical results for the temporal evolution of the average temperature of the tube wall, {theta}{sub av,} is plotted for different nondimensional parameters such as conduction parameter, {alpha}, the aspect ratios of the tube, {epsilon} and {epsilon}{sub 0} and the index of power-law fluid, n. (orig.)

Power law analysis of the human microbiome.

Science.gov (United States)

Ma, Zhanshan Sam

2015-11-01

Taylor's (1961, Nature, 189:732) power law, a power function (V = am(b) ) describing the scaling relationship between the mean and variance of population abundances of organisms, has been found to govern the population abundance distributions of single species in both space and time in macroecology. It is regarded as one of few generalities in ecology, and its parameter b has been widely applied to characterize spatial aggregation (i.e. heterogeneity) and temporal stability of single-species populations. Here, we test its applicability to bacterial populations in the human microbiome using extensive data sets generated by the US-NIH Human Microbiome Project (HMP). We further propose extending Taylor's power law from the population to the community level, and accordingly introduce four types of power-law extensions (PLEs): type I PLE for community spatial aggregation (heterogeneity), type II PLE for community temporal aggregation (stability), type III PLE for mixed-species population spatial aggregation (heterogeneity) and type IV PLE for mixed-species population temporal aggregation (stability). Our results show that fittings to the four PLEs with HMP data were statistically extremely significant and their parameters are ecologically sound, hence confirming the validity of the power law at both the population and community levels. These findings not only provide a powerful tool to characterize the aggregations of population and community in both time and space, offering important insights into community heterogeneity in space and/or stability in time, but also underscore the three general properties of power laws (scale invariance, no average and universality) and their specific manifestations in our four PLEs. © 2015 John Wiley & Sons Ltd.

Jell-O Optics: Edibly Exploring Snell's Law and Optical Power

Science.gov (United States)

Hendryx, Jennifer; Reynolds, Mathias

2012-03-01

This presentation details a laboratory exercise and/or demonstration of refraction with an inexpensive, simple set-up: a pan of Jell-O, protractors, and laser pointers. This activity is presented from the perspective of an optical sciences graduate student who has spent the school year team-teaching high school math and physics (through Academic Decathlon). The goal is to present some of the fundamentals of optics with an enjoyable and affordable approach. The concepts include Snell's law, index of refraction, and optical power/focal length as they relate to the curvature of a lens.

Transient forced convection with viscous dissipation to power-law fluids in thermal entrance region of circular ducts with constant wall heat flux

International Nuclear Information System (INIS)

Dehkordi, Asghar Molaei; Mohammadi, Ali Asghar

2009-01-01

A numerical investigation was conducted on the transient behavior of a hydrodynamically, fully developed, laminar flow of power-law fluids in the thermally developing entrance region of circular ducts taking into account the effect of viscous dissipation but neglecting the effect of axial conduction. In this regard, the unsteady state thermal energy equation was solved by using a finite difference method, whereas the steady state thermal energy equation without wall heat flux was solved analytically as the initial condition of the former. The effects of the power-law index and wall heat flux on the local Nusselt number and thermal entrance length were investigated. Moreover, the local Nusselt number of steady state conditions was correlated in terms of the power-law index and wall heat flux and compared with literature data, which were obtained by an analytic solution for Newtonian fluids. Furthermore, a relationship was proposed for the thermal entrance length

Refractive index dispersion law of silica aerogel

International Nuclear Information System (INIS)

Bellunato, T.; Calvi, M.; Matteuzzi, C.; Musy, M.; Perego, D.L.; Storaci, B.

2007-01-01

This paper presents measurements of the refractive index of a hygroscopic silica aerogel block at several wavelengths. The measurements, performed with a monochromator, have been compared with different parameterisations for n(λ), in order to determine the best chromaticity law for the aerogel. This is an important input for design and operation of RICH detectors with silica aerogel radiator. (orig.)

Estimation of inflation parameters for Perturbed Power Law model using recent CMB measurements

International Nuclear Information System (INIS)

Mukherjee, Suvodip; Das, Santanu; Souradeep, Tarun; Joy, Minu

2015-01-01

Cosmic Microwave Background (CMB) is an important probe for understanding the inflationary era of the Universe. We consider the Perturbed Power Law (PPL) model of inflation which is a soft deviation from Power Law (PL) inflationary model. This model captures the effect of higher order derivative of Hubble parameter during inflation, which in turn leads to a non-zero effective mass m eff for the inflaton field. The higher order derivatives of Hubble parameter at leading order sources constant difference in the spectral index for scalar and tensor perturbation going beyond PL model of inflation. PPL model have two observable independent parameters, namely spectral index for tensor perturbation ν t and change in spectral index for scalar perturbation ν st to explain the observed features in the scalar and tensor power spectrum of perturbation. From the recent measurements of CMB power spectra by WMAP, Planck and BICEP-2 for temperature and polarization, we estimate the feasibility of PPL model with standard ΛCDM model. Although BICEP-2 claimed a detection of r=0.2, estimates of dust contamination provided by Planck have left open the possibility that only upper bound on r will be expected in a joint analysis. As a result we consider different upper bounds on the value of r and show that PPL model can explain a lower value of tensor to scalar ratio (r<0.1 or r<0.01) for a scalar spectral index of n s =0.96 by having a non-zero value of effective mass of the inflaton field m 2 eff /H 2 . The analysis with WP + Planck likelihood shows a non-zero detection of m 2 eff /H 2 with 5.7 σ and 8.1 σ respectively for r<0.1 and r<0.01. Whereas, with BICEP-2 likelihood m 2 eff /H 2  = −0.0237 ± 0.0135 which is consistent with zero

MHD axisymmetric flow of power-law fluid over an unsteady stretching sheet with convective boundary conditions

Directory of Open Access Journals (Sweden)

Jawad Ahmed

Full Text Available This paper examines the boundary layer flow and heat transfer characteristic in power law fluid model over unsteady radially stretching sheet under the influence of convective boundary conditions. A uniform magnetic field is applied transversely to the direction of the flow. The governing time dependent nonlinear boundary layer equations are reduced into nonlinear ordinary differential equations with the help of similarity transformations. The transformed coupled ordinary differential equations are then solved analytically by homotopy analysis method (HAM and numerically by shooting procedure. Effects of various governing parameters like, power law index n, magnetic parameter M, unsteadiness A, suction/injection S, Biot number γ and generalized Prandtl number Pr on velocity, temperature, local skin friction and the local Nusselt number are studied and discussed. It is found from the analysis that the magnetic parameter diminishes the velocity profile and the corresponding thermal boundary layer thickness. Keywords: Axisymmetric flow, Power law fluid, Unsteady stretching, Convective boundary conditions

Crustal Viscosity Structure Estimated from Multi-Phase Mixing Theory

Science.gov (United States)

Shinevar, W. J.; Behn, M. D.; Hirth, G.

2014-12-01

Estimates of lower crustal viscosity are typically constrained by analyses of isostatic rebound, post seismic creep, and laboratory-derived flow laws for crustal rocks and minerals. Here we follow a new approach for calculating the viscosity structure of the lower continental crust. We use Perple_X to calculate mineral assemblages for different crustal compositions. Effective viscosity is then calculated using the rheologic mixing model of Huet et al. (2014) incorporating flow laws for each mineral phase. Calculations are performed along geotherms appropriate for the Basin and Range, Tibetan Plateau, Colorado Plateau, and the San Andreas Fault. To assess the role of crustal composition on viscosity, we examined two compositional gradients extending from an upper crust with ~67 wt% SiO2 to a lower crust that is either: (i) basaltic with ~53 wt% SiO2 (Rudnick and Gao, 2003), or (ii) andesitic with ~64% SiO2 (Hacker et al., 2011). In all cases, the middle continental crust has a viscosity that is 2-3 orders of magnitude greater than that inferred for wet quartz, a common proxy for mid-crustal viscosities. An andesitic lower crust results in viscosities of 1020-1021 Pa-s and 1021-1022 Pa-s for hotter and colder crustal geotherms, respectively. A mafic lower crust predicts viscosities that are an order of magnitude higher for the same geotherm. In all cases, the viscosity calculated from the mixing model decreases less with depth compared to single-phase estimates. Lastly, for anhydrous conditions in which alpha quartz is stable, we find that there is a strong correlation between Vp/Vs and bulk viscosity; in contrast, little to no correlation exists for hydrous conditions.

Viscosity of particle laden films

Directory of Open Access Journals (Sweden)

Timounay Yousra

2017-01-01

Full Text Available We perform retraction experiments on soap films where large particles bridge the two interfaces. Local velocities are measured by PIV during the unstationnary regime. The velocity variation in time and space can be described by a continuous fluid model from which effective viscosity (shear and dilatational of particulate films is measured. The 2D effective viscosity of particulate films η2D increases with particle surface fraction ϕ: at low ϕ, it tends to the interfacial dilatational viscosity of the liquid/air interfaces and it diverges at the critical particle surface fraction ϕc ≃ 0.84. Experimental data agree with classical viscosity laws of hard spheres suspensions adapted to the 2D geometry, assuming viscous dissipation resulting from the squeeze of the liquid/air interfaces between the particles. Finally, we show that the observed viscous dissipation in particulate films has to be considered to describe the edge velocity during a retraction experiment at large particle coverage.

Viscosity of particle laden films

Science.gov (United States)

Timounay, Yousra; Rouyer, Florence

2017-06-01

We perform retraction experiments on soap films where large particles bridge the two interfaces. Local velocities are measured by PIV during the unstationnary regime. The velocity variation in time and space can be described by a continuous fluid model from which effective viscosity (shear and dilatational) of particulate films is measured. The 2D effective viscosity of particulate films η2D increases with particle surface fraction ϕ: at low ϕ, it tends to the interfacial dilatational viscosity of the liquid/air interfaces and it diverges at the critical particle surface fraction ϕc ≃ 0.84. Experimental data agree with classical viscosity laws of hard spheres suspensions adapted to the 2D geometry, assuming viscous dissipation resulting from the squeeze of the liquid/air interfaces between the particles. Finally, we show that the observed viscous dissipation in particulate films has to be considered to describe the edge velocity during a retraction experiment at large particle coverage.

Numerical simulation of nanofluids based on power-law fluids with flow and heat transfer

Science.gov (United States)

Li, Lin; Jiang, Yongyue; Chen, Aixin

2017-04-01

In this paper, we investigate the heat transfer of nanofluids based on power-law fluids and movement of nanoparticles with the effect of thermophoresis in a rotating circular groove. The velocity of circular groove rotating is a constant and the temperature on the wall is kept to be zero all the time which is different from the temperature of nanofluids in the initial time. The effects of thermophoresis and Brownian diffusion are considered in temperature and concentration equations, and it is assumed that the thermal conductivity of nanofluids is a function of concentration of nanoparticles. Based on numerical results, it can be found that nanofluids improve the process of heat transfer than base fluids in a rotating circular groove. The enhancement of heat transfer increases as the power law index of base fluids decreases.

Stability analysis of WONDY (a hydrocode based on the artifical viscosity method of von Neumann and Richtmyer) for a special case of Maxwell's Law

International Nuclear Information System (INIS)

Hicks, D.L.

1978-01-01

The artification viscosity method of von Neumann and Richtmyer was originally designed and analyzed for stability in the case when the material was an ideal gas. Recently a hydrocode (WONDY) based on the von Neumann-Richymyer scheme was used in calculating wave progagation problems in materials obeying a form of Maxwell's material law; signs of an unstable difference scheme appeared. A stability analysis shows that the timestep restrictions required for stability in certain cases can be more stringent for material laws of the Maxwell type than they are for material laws of the ideal gas type

Power-law Exponent in Multiplicative Langevin Equation with Temporally Correlated Noise

Science.gov (United States)

Morita, Satoru

2018-05-01

Power-law distributions are ubiquitous in nature. Random multiplicative processes are a basic model for the generation of power-law distributions. For discrete-time systems, the power-law exponent is known to decrease as the autocorrelation time of the multiplier increases. However, for continuous-time systems, it is not yet clear how the temporal correlation affects the power-law behavior. Herein, we analytically investigated a multiplicative Langevin equation with colored noise. We show that the power-law exponent depends on the details of the multiplicative noise, in contrast to the case of discrete-time systems.

Spreading dynamics of power-law fluid droplets

International Nuclear Information System (INIS)

Liang Zhanpeng; Peng Xiaofeng; Wang Xiaodong; Lee, D-J; Su Ay

2009-01-01

This paper aims at providing a summary of the theoretical models available for non-Newtonian fluid spreading dynamics. Experimental findings and model predictions for a Newtonian fluid spreading test are briefly reviewed. Then how the complete wetting and partial wetting power-law fluids spread over a solid substrate is examined. The possible extension of Newtonian fluid models to power-law fluids is also discussed.

Power-law relaxation in human violent conflicts

Science.gov (United States)

Picoli, Sergio; Antonio, Fernando J.; Itami, Andreia S.; Mendes, Renio S.

2017-08-01

We study relaxation patterns of violent conflicts after bursts of activity. Data were obtained from available catalogs on the conflicts in Iraq, Afghanistan and Northern Ireland. We find several examples in each catalog for which the observed relaxation curves can be well described by an asymptotic power-law decay (the analog of the Omori's law in geophysics). The power-law exponents are robust, nearly independent of the conflict. We also discuss the exogenous or endogenous nature of the shocks. Our results suggest that violent conflicts share with earthquakes and other natural and social phenomena a common feature in the dynamics of aftershocks.

POWER-LAW TEMPLATE FOR INFRARED POINT-SOURCE CLUSTERING

Energy Technology Data Exchange (ETDEWEB)

Addison, Graeme E.; Dunkley, Joanna [Sub-department of Astrophysics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH (United Kingdom); Hajian, Amir; Das, Sudeep; Hincks, Adam D.; Page, Lyman A.; Staggs, Suzanne T. [Joseph Henry Laboratories of Physics, Jadwin Hall, Princeton University, Princeton, NJ 08544 (United States); Viero, Marco [Department of Astronomy, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Bond, J. Richard [Canadian Institute for Theoretical Astrophysics, University of Toronto, Toronto, ON M5S 3H8 (Canada); Devlin, Mark J.; Reese, Erik D. [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104 (United States); Halpern, Mark; Scott, Douglas [Department of Physics and Astronomy, University of British Columbia, Vancouver, BC V6T 1Z4 (Canada); Hlozek, Renee; Marriage, Tobias A.; Spergel, David N. [Department of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ 08544 (United States); Moodley, Kavilan [Astrophysics and Cosmology Research Unit, School of Mathematical Sciences, University of KwaZulu-Natal, Durban 4041 (South Africa); Wollack, Edward [NASA/Goddard Space Flight Center, Code 665, Greenbelt, MD 20771 (United States)

2012-06-20

We perform a combined fit to angular power spectra of unresolved infrared (IR) point sources from the Planck satellite (at 217, 353, 545, and 857 GHz, over angular scales 100 {approx}< l {approx}< 2200), the Balloon-borne Large-Aperture Submillimeter Telescope (BLAST; 250, 350, and 500 {mu}m; 1000 {approx}< l {approx}< 9000), and from correlating BLAST and Atacama Cosmology Telescope (ACT; 148 and 218 GHz) maps. We find that the clustered power over the range of angular scales and frequencies considered is well fitted by a simple power law of the form C{sup clust}{sub l}{proportional_to}l{sup -n} with n = 1.25 {+-} 0.06. While the IR sources are understood to lie at a range of redshifts, with a variety of dust properties, we find that the frequency dependence of the clustering power can be described by the square of a modified blackbody, {nu}{sup {beta}} B({nu}, T{sub eff}), with a single emissivity index {beta} = 2.20 {+-} 0.07 and effective temperature T{sub eff} = 9.7 K. Our predictions for the clustering amplitude are consistent with existing ACT and South Pole Telescope results at around 150 and 220 GHz, as is our prediction for the effective dust spectral index, which we find to be {alpha}{sub 150-220} = 3.68 {+-} 0.07 between 150 and 220 GHz. Our constraints on the clustering shape and frequency dependence can be used to model the IR clustering as a contaminant in cosmic microwave background anisotropy measurements. The combined Planck and BLAST data also rule out a linear bias clustering model.

Convective hydromagnetic instabilities of a power-law liquid saturating a porous medium: Flux conditions

Science.gov (United States)

Chahtour, C.; Ben Hamed, H.; Beji, H.; Guizani, A.; Alimi, W.

2018-01-01

We investigate how an external imposed magnetic field affects thermal instability in a horizontal shallow porous cavity saturated by a non-Newtonian power-law liquid. The magnetic field is assumed to be constant and parallel to the gravity. A uniform heat flux is applied to the horizontal walls of the layer while the vertical walls are adiabatic. We use linear stability analysis to find expressions for the critical Rayleigh number as a function of the power-law index and the intensity of the magnetic field. We use nonlinear parallel flow theory to find some explicit solutions of the problem, and we use finite difference numerical simulations to solve the full nonlinear equations. We show how the presence of magnetic field alters the known hydrodynamical result of Newtonian flows and power-law flows and how it causes the presence of subcritical finite amplitude convection for both pseudoplastic and dilatant fluids. We also show that in the limit of very strong magnetic field, the dissipation of energy by Joule effect dominates the dissipation of energy by shear stress and gives to the liquid an inviscid character.

The role of fluid viscosity in an immersed granular collapse

Science.gov (United States)

Yang, Geng Chao; Kwok, Chung Yee; Sobral, Yuri Dumaresq

2017-06-01

Instabilities of immersed slopes and cliffs can lead to catastrophic events that involve a sudden release of huge soil mass. The scaled deposit height and runout distance are found to follow simple power laws when a granular column collapses on a horizontal plane. However, if the granular column is submerged in a fluid, the mobility of the granular collapse due to high inertia effects will be reduced by fluid-particle interactions. In this study, the effects of fluid viscosity on granular collapse is investigated qualitatively by adopting a numerical approach based on the coupled lattice Boltzmann method (LBM) and discrete element method (DEM). It is found that the granular collapse can be dramatically slowed down due to the presence of viscous fluids. For the considered granular configuration, when the fluid viscosity increases. the runout distance decreases and the final deposition shows a larger deposit angle.

The role of fluid viscosity in an immersed granular collapse

Directory of Open Access Journals (Sweden)

Yang Geng Chao

2017-01-01

Full Text Available Instabilities of immersed slopes and cliffs can lead to catastrophic events that involve a sudden release of huge soil mass. The scaled deposit height and runout distance are found to follow simple power laws when a granular column collapses on a horizontal plane. However, if the granular column is submerged in a fluid, the mobility of the granular collapse due to high inertia effects will be reduced by fluid-particle interactions. In this study, the effects of fluid viscosity on granular collapse is investigated qualitatively by adopting a numerical approach based on the coupled lattice Boltzmann method (LBM and discrete element method (DEM. It is found that the granular collapse can be dramatically slowed down due to the presence of viscous fluids. For the considered granular configuration, when the fluid viscosity increases. the runout distance decreases and the final deposition shows a larger deposit angle.

Power-law creep behavior of a semiflexible chain.

Science.gov (United States)

Majumdar, Arnab; Suki, Béla; Rosenblatt, Noah; Alencar, Adriano M; Stamenović, Dimitrije

2008-10-01

Rheological properties of adherent cells are essential for their physiological functions, and microrheological measurements on living cells have shown that their viscoelastic responses follow a weak power law over a wide range of time scales. This power law is also influenced by mechanical prestress borne by the cytoskeleton, suggesting that cytoskeletal prestress determines the cell's viscoelasticity, but the biophysical origins of this behavior are largely unknown. We have recently developed a stochastic two-dimensional model of an elastically joined chain that links the power-law rheology to the prestress. Here we use a similar approach to study the creep response of a prestressed three-dimensional elastically jointed chain as a viscoelastic model of semiflexible polymers that comprise the prestressed cytoskeletal lattice. Using a Monte Carlo based algorithm, we show that numerical simulations of the chain's creep behavior closely correspond to the behavior observed experimentally in living cells. The power-law creep behavior results from a finite-speed propagation of free energy from the chain's end points toward the center of the chain in response to an externally applied stretching force. The property that links the power law to the prestress is the chain's stiffening with increasing prestress, which originates from entropic and enthalpic contributions. These results indicate that the essential features of cellular rheology can be explained by the viscoelastic behaviors of individual semiflexible polymers of the cytoskeleton.

Power laws for gravity and topography of Solar System bodies

Science.gov (United States)

Ermakov, A.; Park, R. S.; Bills, B. G.

2017-12-01

When a spacecraft visits a planetary body, it is useful to be able to predict its gravitational and topographic properties. This knowledge is important for determining the level of perturbations in spacecraft's motion as well as for planning the observation campaign. It has been known for the Earth that the power spectrum of gravity follows a power law, also known as the Kaula rule (Kaula, 1963; Rapp, 1989). A similar rule was derived for topography (Vening-Meinesz, 1951). The goal of this paper is to generalize the power law that can characterize the gravity and topography power spectra for bodies across a wide range of size. We have analyzed shape power spectra of the bodies that have either global shape and gravity field measured. These bodies span across five orders of magnitude in their radii and surface gravities and include terrestrial planets, icy moons and minor bodies. We have found that despite having different internal structure, composition and mechanical properties, the topography power spectrum of these bodies' shapes can be modeled with a similar power law rescaled by the surface gravity. Having empirically found a power law for topography, we can map it to a gravity power law. Special care should be taken for low-degree harmonic coefficients due to potential isostatic compensation. For minor bodies, uniform density can be assumed. The gravity coefficients are a linear function of the shape coefficients for close-to-spherical bodoes. In this case, the power law for gravity will be steeper than the power law of topography due to the factor (2n+1) in the gravity expansion (e.g. Eq. 10 in Wieczorek & Phillips, 1998). Higher powers of topography must be retained for irregularly shaped bodies, which breaks the linearity. Therefore, we propose the following procedure to derive an a priori constraint for gravity. First, a surface gravity needs to be determined assuming typical density for the relevant class of bodies. Second, the scaling coefficient of the

On the structure and phase transitions of power-law Poissonian ensembles

Science.gov (United States)

Eliazar, Iddo; Oshanin, Gleb

2012-10-01

Power-law Poissonian ensembles are Poisson processes that are defined on the positive half-line, and that are governed by power-law intensities. Power-law Poissonian ensembles are stochastic objects of fundamental significance; they uniquely display an array of fractal features and they uniquely generate a span of important applications. In this paper we apply three different methods—oligarchic analysis, Lorenzian analysis and heterogeneity analysis—to explore power-law Poissonian ensembles. The amalgamation of these analyses, combined with the topology of power-law Poissonian ensembles, establishes a detailed and multi-faceted picture of the statistical structure and the statistical phase transitions of these elemental ensembles.

The new law on radiation and nuclear power

International Nuclear Information System (INIS)

Niittylae, A.

1990-01-01

The Law on Nuclear Energy, which entered into force in 1988, controls the use of nuclear power. The new Law on Radiation is under consideration in the Parliament. The internationally approved main principles on radiation protection are the basis of the law. In the article, these principles and the contents of the law are described

On the universality of power laws for tokamak plasma predictions

Science.gov (United States)

Garcia, J.; Cambon, D.; Contributors, JET

2018-02-01

Significant deviations from well established power laws for the thermal energy confinement time, obtained from extensive databases analysis as the IPB98(y,2), have been recently reported in dedicated power scans. In order to illuminate the adequacy, validity and universality of power laws as tools for predicting plasma performance, a simplified analysis has been carried out in the framework of a minimal modeling for heat transport which is, however, able to account for the interplay between turbulence and collinear effects with the input power known to play a role in experiments with significant deviations from such power laws. Whereas at low powers, the usual scaling laws are recovered with little influence of other plasma parameters, resulting in a robust power low exponent, at high power it is shown how the exponents obtained are extremely sensitive to the heating deposition, the q-profile or even the sampling or the number of points considered due to highly non-linear behavior of the heat transport. In particular circumstances, even a minimum of the thermal energy confinement time with the input power can be obtained, which means that the approach of the energy confinement time as a power law might be intrinsically invalid. Therefore plasma predictions with a power law approximation with a constant exponent obtained from a regression of a broad range of powers and other plasma parameters which can non-linearly affect and suppress heat transport, can lead to misleading results suggesting that this approach should be taken cautiously and its results continuously compared with modeling which can properly capture the underline physics, as gyrokinetic simulations.

Kant on causal laws and powers.

Science.gov (United States)

Henschen, Tobias

2014-12-01

The aim of the paper is threefold. Its first aim is to defend Eric Watkins's claim that for Kant, a cause is not an event but a causal power: a power that is borne by a substance, and that, when active, brings about its effect, i.e. a change of the states of another substance, by generating a continuous flow of intermediate states of that substance. The second aim of the paper is to argue against Watkins that the Kantian concept of causal power is not the pre-critical concept of real ground but the category of causality, and that Kant holds with Hume that causal laws cannot be inferred non-inductively (that he accordingly has no intention to show in the Second analogy or elsewhere that events fall under causal laws). The third aim of the paper is to compare the Kantian position on causality with central tenets of contemporary powers ontology: it argues that unlike the variants endorsed by contemporary powers theorists, the Kantian variants of these tenets are resistant to objections that neo-Humeans raise to these tenets.

The origin of power-law distributions in self-organized criticality

International Nuclear Information System (INIS)

Yang, C B

2004-01-01

The origin of power-law distributions in self-organized criticality is investigated by treating the variation of the number of active sites in the system as a stochastic process. An avalanche is then regarded as a first-return random-walk process in a one-dimensional lattice. Power-law distributions of the lifetime and spatial size are found when the random walk is unbiased with equal probability to move in opposite directions. This shows that power-law distributions in self-organized criticality may be caused by the balance of competitive interactions. At the mean time, the mean spatial size for avalanches with the same lifetime is found to increase in a power law with the lifetime. (letter to the editor)

Measurement of viscosity of slush at high shear rates

OpenAIRE

小林, 俊一; 川村, 公之; 津川, 圭一; 和泉, 薫; Kobayashi, Shun'ichi; Kawamura, Kimiyuki; Tugawa, Keiichi; Izumi, Kaoru

1988-01-01

Measurements of viscosity of slush were carried out using a method of flow along an inclined smooth surface in a 0℃cold room. The method was used to get the values of viscosity under high shear rates (25 and 75s^). From our experiments two important results were obtained: 1) the viscosity of slush decreases with increasing shear rates; 2) The fluid behavior is pseudoplastic that the values of non-Newtonian index of viscosity were less than unity.

Econophysical anchoring of unimodal power-law distributions

International Nuclear Information System (INIS)

Eliazar, Iddo I; Cohen, Morrel H

2013-01-01

The sciences are abundant with size distributions whose densities have a unimodal shape and power-law tails both at zero and at infinity. The quintessential examples of such unimodal and power-law (UPL) distributions are the sizes of income and wealth in human societies. While the tails of UPL distributions are precisely quantified by their corresponding power-law exponents, their bulks are only qualitatively characterized as unimodal. Consequently, different statistical models of UPL distributions exist, the most popular considering lognormal bulks. In this paper we present a general econophysical framework for UPL distributions termed ‘the anchoring method’. This method: (i) universally approximates UPL distributions via three ‘anchors’ set at zero, at infinity, and at an intermediate point between zero and infinity (e.g. the mode); (ii) is highly versatile and broadly applicable; (iii) encompasses the existing statistical models of UPL distributions as special cases; (iv) facilitates the introduction of new statistical models of UPL distributions and (v) yields a socioeconophysical analysis of UPL distributions. (paper)

Models of fragmentation with composite power laws

Science.gov (United States)

Tavassoli, Z.; Rodgers, G. J.

1999-06-01

Some models for binary fragmentation are introduced in which a time dependent transition size produces two regions of fragment sizes above and below the transition size. In the first model we assume a fixed rate of fragmentation for the largest fragment and two different rates of fragmentation in the two regions of sizes above and below the transition size. The model is solved exactly in the long time limit to reveal stable time-invariant solutions for the fragment size and mass distributions. These solutions exhibit composite power law behaviours; power laws with two different exponents for fragments in smaller and larger regions. A special case of the model with no fragmentation in the smaller size region is also examined. Another model is also introduced which have three regions of fragment sizes with different rates of fragmentation. The similarities between the stable distributions in our models and composite power law distributions from experimental work on shock fragmentation of long thin glass rods and thick clay plates are discussed.

Power-law and intermediate inflationary models in f(T)-gravity

Energy Technology Data Exchange (ETDEWEB)

Rezazadeh, K. [Department of Physics, University of Kurdistan,Pasdaran St., Sanandaj (Iran, Islamic Republic of); Abdolmaleki, A. [Research Institute for Astronomy Astrophysics of Maragha (RIAAM),P.O. Box 55134-441, Maragha (Iran, Islamic Republic of); Karami, K. [Department of Physics, University of Kurdistan,Pasdaran St., Sanandaj (Iran, Islamic Republic of)

2016-01-21

We study inflation in the framework of f(T)-gravity in the presence of a canonical scalar field. After reviewing the basic equations governing the background cosmology in f(T)-gravity, we turn to study the cosmological perturbations and obtain the evolutionary equations for the scalar and tensor perturbations. Solving those equations, we find the power spectra for the scalar and tensor perturbations. Then, we consider a power-law f(T) function and investigate the inflationary models with the power-law and intermediate scale factors. We see that in contrast with the standard inflationary scenario based on the Einstein gravity, the power-law and intermediate inflationary models in f(T)-gravity can be compatible with the observational results of Planck 2015 at 68% CL. We find that in our f(T) setting, the potentials responsible for the both power-law and intermediate inflationary models have the power-law form V(ϕ)∝ϕ{sup m} but the power m is different for them. Therefore, we can refine some of power-law inflationary potentials in the framework of f(T)-gravity while they are disfavored by the observational data in the standard inflationary scenario. Interestingly enough, is that the self-interacting quartic potential V(ϕ)∝ϕ{sup 4} which has special reheating properties, can be consistent with the Planck 2015 data in our f(T) scenario while it is ruled out in the standard inflationary scenario.

Power-law and intermediate inflationary models in f(T)-gravity

International Nuclear Information System (INIS)

Rezazadeh, K.; Abdolmaleki, A.; Karami, K.

2016-01-01

We study inflation in the framework of f(T)-gravity in the presence of a canonical scalar field. After reviewing the basic equations governing the background cosmology in f(T)-gravity, we turn to study the cosmological perturbations and obtain the evolutionary equations for the scalar and tensor perturbations. Solving those equations, we find the power spectra for the scalar and tensor perturbations. Then, we consider a power-law f(T) function and investigate the inflationary models with the power-law and intermediate scale factors. We see that in contrast with the standard inflationary scenario based on the Einstein gravity, the power-law and intermediate inflationary models in f(T)-gravity can be compatible with the observational results of Planck 2015 at 68% CL. We find that in our f(T) setting, the potentials responsible for the both power-law and intermediate inflationary models have the power-law form V(ϕ)∝ϕ m but the power m is different for them. Therefore, we can refine some of power-law inflationary potentials in the framework of f(T)-gravity while they are disfavored by the observational data in the standard inflationary scenario. Interestingly enough, is that the self-interacting quartic potential V(ϕ)∝ϕ 4 which has special reheating properties, can be consistent with the Planck 2015 data in our f(T) scenario while it is ruled out in the standard inflationary scenario.

Viscosity of ring polymer melts

KAUST Repository

Pasquino, Rossana

2013-10-15

We have measured the linear rheology of critically purified ring polyisoprenes, polystyrenes, and polyethyleneoxides of different molar masses. The ratio of the zero-shear viscosities of linear polymer melts η0,linear to their ring counterparts η0,ring at isofrictional conditions is discussed as a function of the number of entanglements Z. In the unentangled regime η0,linear/η 0,ring is virtually constant, consistent with the earlier data, atomistic simulations, and the theoretical expectation η0,linear/ η0,ring = 2. In the entanglement regime, the Z-dependence of ring viscosity is much weaker than that of linear polymers, in qualitative agreement with predictions from scaling theory and simulations. The power-law extracted from the available experimental data in the rather limited range 1 < Z < 20, η0,linear/η0,ring ∼ Z 1.2±0.3, is weaker than the scaling prediction (η0,linear/η0,ring ∼ Z 1.6±0.3) and the simulations (η0,linear/ η0,ring ∼ Z2.0±0.3). Nevertheless, the present collection of state-of-the-art experimental data unambiguously demonstrates that rings exhibit a universal trend clearly departing from that of their linear counterparts, and hence it represents a major step toward resolving a 30-year-old problem. © 2013 American Chemical Society.

Viscosity of ring polymer melts

KAUST Repository

Pasquino, Rossana; Vasilakopoulos, Thodoris C.; Jeong, Youncheol; Lee, Hyojoon; Rogers, Simon A.; Sakellariou, Georgios; Allgaier, Jü rgen B.; Takano, Atsushi; Brá s, Ana Rita E; Chang, Taihyun; Gooß en, Sebastian; Pyckhout-Hintzen, Wim; Wischnewski, Andreas; Hadjichristidis, Nikolaos; Richter, Dieter R.; Rubinstein, Michael H.; Vlassopoulos, Dimitris

2013-01-01

We have measured the linear rheology of critically purified ring polyisoprenes, polystyrenes, and polyethyleneoxides of different molar masses. The ratio of the zero-shear viscosities of linear polymer melts η0,linear to their ring counterparts η0,ring at isofrictional conditions is discussed as a function of the number of entanglements Z. In the unentangled regime η0,linear/η 0,ring is virtually constant, consistent with the earlier data, atomistic simulations, and the theoretical expectation η0,linear/ η0,ring = 2. In the entanglement regime, the Z-dependence of ring viscosity is much weaker than that of linear polymers, in qualitative agreement with predictions from scaling theory and simulations. The power-law extracted from the available experimental data in the rather limited range 1 < Z < 20, η0,linear/η0,ring ∼ Z 1.2±0.3, is weaker than the scaling prediction (η0,linear/η0,ring ∼ Z 1.6±0.3) and the simulations (η0,linear/ η0,ring ∼ Z2.0±0.3). Nevertheless, the present collection of state-of-the-art experimental data unambiguously demonstrates that rings exhibit a universal trend clearly departing from that of their linear counterparts, and hence it represents a major step toward resolving a 30-year-old problem. © 2013 American Chemical Society.

Power-law and runaway growth in conserved aggregation systems

International Nuclear Information System (INIS)

Yamamoto, Hiroshi; Ohtsuki, Toshiya; Fujihara, Akihiro; Tanimoto, Satoshi

2006-01-01

The z-transform technique is used to analyze the Smoluchowski coagulation equation for conserved aggregation systems. A universal power law with the exponent -5/2 appears when a total 'mass' has a certain critical value. Below the threshold, ordinary scaling relations hold and the system exhibits a behavior like usual critical phenomena. Above the threshold, in contrast, the excess amount of mass coagulates into a runaway member, and remaining members follow the power law. Here the runaway growth coexists with the power law. It is argued that these behaviors are observed universally in conserved aggregation processes

Financial power laws: Empirical evidence, models, and mechanisms

International Nuclear Information System (INIS)

Lux, Thomas; Alfarano, Simone

2016-01-01

Financial markets (share markets, foreign exchange markets and others) are all characterized by a number of universal power laws. The most prominent example is the ubiquitous finding of a robust, approximately cubic power law characterizing the distribution of large returns. A similarly robust feature is long-range dependence in volatility (i.e., hyperbolic decline of its autocorrelation function). The recent literature adds temporal scaling of trading volume and multi-scaling of higher moments of returns. Increasing awareness of these properties has recently spurred attempts at theoretical explanations of the emergence of these key characteristics form the market process. In principle, different types of dynamic processes could be responsible for these power-laws. Examples to be found in the economics literature include multiplicative stochastic processes as well as dynamic processes with multiple equilibria. Though both types of dynamics are characterized by intermittent behavior which occasionally generates large bursts of activity, they can be based on fundamentally different perceptions of the trading process. The present paper reviews both the analytical background of the power laws emerging from the above data generating mechanisms as well as pertinent models proposed in the economics literature.

glutamic acid from high-viscosity fermentation broth

African Journals Online (AJOL)

Measurement of IR spectrum was performed using an IR spectrophotometer with ... Results: The results showed that the γ-PGA yield was 35 g/L. The viscosity of ... of Pharmaceutical Research is indexed by Science Citation Index (SciSearch), ...

Testing power-law cross-correlations: Rescaled covariance test

Czech Academy of Sciences Publication Activity Database

Krištoufek, Ladislav

2013-01-01

Roč. 86, č. 10 (2013), 418-1-418-15 ISSN 1434-6028 R&D Projects: GA ČR GA402/09/0965 Institutional support: RVO:67985556 Keywords : power-law cross-correlations * testing * long-term memory Subject RIV: AH - Economics Impact factor: 1.463, year: 2013 http://library.utia.cas.cz/separaty/2013/E/kristoufek-testing power-law cross-correlations rescaled covariance test.pdf

Formation of hard power laws in the energetic particle spectra resulting from relativistic magnetic reconnection.

Science.gov (United States)

Guo, Fan; Li, Hui; Daughton, William; Liu, Yi-Hsin

2014-10-10

Using fully kinetic simulations, we demonstrate that magnetic reconnection in relativistic plasmas is highly efficient at accelerating particles through a first-order Fermi process resulting from the curvature drift of particles in the direction of the electric field induced by the relativistic flows. This mechanism gives rise to the formation of hard power-law spectra in parameter regimes where the energy density in the reconnecting field exceeds the rest mass energy density σ ≡ B(2)/(4πnm(e)c(2))>1 and when the system size is sufficiently large. In the limit σ ≫ 1, the spectral index approaches p = 1 and most of the available energy is converted into nonthermal particles. A simple analytic model is proposed which explains these key features and predicts a general condition under which hard power-law spectra will be generated from magnetic reconnection.

High-pressure viscosity measurements for the ethanol plus toluene binary system

DEFF Research Database (Denmark)

Zeberg-Mikkelsen, Claus Kjær; Baylaucq, A.; Watson, G.

2005-01-01

measured with a classical capillary viscometer (Ubbelohde) with an uncertainty of 1%. A total of 209 experimental measurements have been obtained for this binary system, which reveals a non-monotonic behavior of the viscosity as a function of the composition, with a minimum. The viscosity behavior...... interacting system showing a negative deviation from ideality. The viscosity of this binary system is represented by the Grunberg-Nissan and the Katti-Chaudhri mixing laws with an overall uncertainty of 12% and 8%, respectively. The viscosity of methanol (23 point) has also been measured in order to verify...

Online shear viscosity measurement of starchy melts enriched in wheat bran.

Science.gov (United States)

Robin, Frédéric; Bovet, Nicolas; Pineau, Nicolas; Schuchmann, Heike P; Palzer, Stefan

2011-01-01

Addition of wheat bran to flours modifies their expansion properties after cooking extrusion. This can be attributed to changes in the melt shear viscosity at the die. The effect of wheat bran concentration added to achieve 2 levels of dietary fibers of 12. 6% and 24.4%, and process conditions on the shear viscosity of wheat flour was therefore assessed using an online twin-slit rheometer. The shear viscosity measured at 30 s⁻¹ ranged from 9.5 × 10³ to 53.4 × 10³ Pa s. Regardless of the process conditions and bran concentration, the extruded melts showed a pseudoplastic behavior with a power law index n ranging from 0.05 to 0.27. Increasing the barrel temperature of the extruder from 120 to 180 °C, the water content from 18% to 22% or the screw speed from 400 to 800 rpm significantly decreased the melt shear viscosity at the extruder exit. The addition of bran significantly increased the melt shear viscosity only at the highest bran concentration. The effect was process condition dependant. Mathematical interpretations, based upon observations, of the experimental data were carried out. They can be used to predict the effect of the process conditions on the melt shear viscosity at the die of extruded wheat flour with increasing bran concentration. The viscosity data will be applied in future works to study the expansion properties of extruded wheat flour supplemented with bran. Incorporation of wheat bran, a readily available and low cost by-product, in extruded puffed foods is constrained due to its negative effect on the product texture. Understanding the effect of wheat bran on rheological properties of extruded melts, driving the final product properties, is essential to provide solutions to the food industry and enhance its use. © 2011 Institute of Food Technologists®

Evapotranspiration Power Law in Self-Organized and Human-Managed Ecosystems

Science.gov (United States)

Zeng, R.; Cai, X.

2017-12-01

Natural systems display a profound degree of self-organization, often apparent even to the untrained eye. However, in this age of increased coupling among human and natural systems, it is unclear to what degree natural organization principles continue to govern human-managed landscapes. Here we present an emerging characteristic of terrestrial evapotranspiration (ET), one of the key components of the water cycle and energy budget, adhered to by both naturally organized and intensively managed landscapes. We find that ET variance and ET mean for ecosystems throughout the world with diverse climate conditions, vegetation structures, and land covers and land uses organize themselves according to a specific power law curve. From multi-source observations, the ET power law curve stands true through varying spatial scales, from field to region. Moreover, a phenomenon of similar ecosystems gravitating toward particular segments of the power law curve, suggests that the feature of self-optimization of ecosystems establishes the ET power law together with climatic conditions. Perhaps surprisingly, we find that landscapes persistently follow the power law curve even upon human-induced transition from rain-fed to irrigated agriculture in the American High Plains and from wetland to agricultural land in American Midwest. As such, the ET power law can be an informative tool for predicting consequences of anthropogenic disturbances to the hydrologic cycle and understanding constraints to sustainable land use.

Pareto law and Pareto index in the income distribution of Japanese companies

OpenAIRE

Ishikawa, Atushi

2004-01-01

In order to study the phenomenon in detail that income distribution follows Pareto law, we analyze the database of high income companies in Japan. We find a quantitative relation between the average capital of the companies and the Pareto index. The larger the average capital becomes, the smaller the Pareto index becomes. From this relation, we can possibly explain that the Pareto index of company income distribution hardly changes, while the Pareto index of personal income distribution chang...

Power-law and exponential rank distributions: A panoramic Gibbsian perspective

International Nuclear Information System (INIS)

Eliazar, Iddo

2015-01-01

Rank distributions are collections of positive sizes ordered either increasingly or decreasingly. Many decreasing rank distributions, formed by the collective collaboration of human actions, follow an inverse power-law relation between ranks and sizes. This remarkable empirical fact is termed Zipf’s law, and one of its quintessential manifestations is the demography of human settlements — which exhibits a harmonic relation between ranks and sizes. In this paper we present a comprehensive statistical-physics analysis of rank distributions, establish that power-law and exponential rank distributions stand out as optimal in various entropy-based senses, and unveil the special role of the harmonic relation between ranks and sizes. Our results extend the contemporary entropy-maximization view of Zipf’s law to a broader, panoramic, Gibbsian perspective of increasing and decreasing power-law and exponential rank distributions — of which Zipf’s law is one out of four pillars

Power-law and exponential rank distributions: A panoramic Gibbsian perspective

Energy Technology Data Exchange (ETDEWEB)

Eliazar, Iddo, E-mail: eliazar@post.tau.ac.il

2015-04-15

Rank distributions are collections of positive sizes ordered either increasingly or decreasingly. Many decreasing rank distributions, formed by the collective collaboration of human actions, follow an inverse power-law relation between ranks and sizes. This remarkable empirical fact is termed Zipf’s law, and one of its quintessential manifestations is the demography of human settlements — which exhibits a harmonic relation between ranks and sizes. In this paper we present a comprehensive statistical-physics analysis of rank distributions, establish that power-law and exponential rank distributions stand out as optimal in various entropy-based senses, and unveil the special role of the harmonic relation between ranks and sizes. Our results extend the contemporary entropy-maximization view of Zipf’s law to a broader, panoramic, Gibbsian perspective of increasing and decreasing power-law and exponential rank distributions — of which Zipf’s law is one out of four pillars.

Variable viscosity and thermal conductivity effects on MHD flow and heat transfer in viscoelastic fluid over a stretching sheet

International Nuclear Information System (INIS)

Salem, Ahmed M.

2007-01-01

The problem of flow and heat transfer of an electrically conducting viscoelastic fluid over a continuously stretching sheet in the presence of a uniform magnetic field is analyzed for the case of power-law variation in the sheet temperature. The fluid viscosity and thermal conductivity are assumed to vary as a function of temperature. The basic equations comprising the balance laws of mass, linear momentum, and energy modified to include the electromagnetic force effect, the viscous dissipation, internal heat generation or absorption and work due to deformation are solved numerically

Constraints on cosmological parameters in power-law cosmology

International Nuclear Information System (INIS)

Rani, Sarita; Singh, J.K.; Altaibayeva, A.; Myrzakulov, R.; Shahalam, M.

2015-01-01

In this paper, we examine observational constraints on the power law cosmology; essentially dependent on two parameters H 0 (Hubble constant) and q (deceleration parameter). We investigate the constraints on these parameters using the latest 28 points of H(z) data and 580 points of Union2.1 compilation data and, compare the results with the results of ΛCDM . We also forecast constraints using a simulated data set for the future JDEM, supernovae survey. Our studies give better insight into power law cosmology than the earlier done analysis by Kumar [arXiv:1109.6924] indicating it tuning well with Union2.1 compilation data but not with H(z) data. However, the constraints obtained on and i.e. H 0 average and q average using the simulated data set for the future JDEM, supernovae survey are found to be inconsistent with the values obtained from the H(z) and Union2.1 compilation data. We also perform the statefinder analysis and find that the power-law cosmological models approach the standard ΛCDM model as q → −1. Finally, we observe that although the power law cosmology explains several prominent features of evolution of the Universe, it fails in details

Do wealth distributions follow power laws? Evidence from ‘rich lists’

Science.gov (United States)

Brzezinski, Michal

2014-07-01

We use data on the wealth of the richest persons taken from the 'rich lists' provided by business magazines like Forbes to verify if the upper tails of wealth distributions follow, as often claimed, a power-law behaviour. The data sets used cover the world's richest persons over 1996-2012, the richest Americans over 1988-2012, the richest Chinese over 2006-2012, and the richest Russians over 2004-2011. Using a recently introduced comprehensive empirical methodology for detecting power laws, which allows for testing the goodness of fit as well as for comparing the power-law model with rival distributions, we find that a power-law model is consistent with data only in 35% of the analysed data sets. Moreover, even if wealth data are consistent with the power-law model, they are usually also consistent with some rivals like the log-normal or stretched exponential distributions.

Kinetics of sub-spinodal dewetting of thin films of thickness dependent viscosity.

Science.gov (United States)

Kotni, Tirumala Rao; Khanna, Rajesh; Sarkar, Jayati

2017-05-04

An alternative explanation of the time varying and very low growth exponents in dewetting of polymer films like polystyrene films is presented based on non-linear simulations. The kinetics of these films is explored within the framework of experimentally observed thickness dependent viscosity. These films exhibit sub-spinodal dewetting via formation of satellite holes in between primary dewetted holes under favorable conditions of excess intermolecular forces and film thicknesses. We find that conditions responsible for sub-spinodal dewetting concurrently lead to remarkable changes in the kinetics of dewetting of even primary holes. For example, the radius of the hole grows in time with a power-law growth exponent sequence of [Formula: see text], in contrast to the usual  ∼4/5. This is due to the cumulative effect of reduced rim mobility due to thickness dependent viscosity and hindrance created by satellite holes.

The p-sphere and the geometric substratum of power-law probability distributions

International Nuclear Information System (INIS)

Vignat, C.; Plastino, A.

2005-01-01

Links between power law probability distributions and marginal distributions of uniform laws on p-spheres in R n show that a mathematical derivation of the Boltzmann-Gibbs distribution necessarily passes through power law ones. Results are also given that link parameters p and n to the value of the non-extensivity parameter q that characterizes these power laws in the context of non-extensive statistics

Unobserved heterogeneity in the power law nonhomogeneous Poisson process

International Nuclear Information System (INIS)

Asfaw, Zeytu Gashaw; Lindqvist, Bo Henry

2015-01-01

A study of possible consequences of heterogeneity in the failure intensity of repairable systems is presented. The basic model studied is the nonhomogeneous Poisson process with power law intensity function. When several similar systems are under observation, the assumption that the corresponding processes are independent and identically distributed is often questionable. In practice there may be an unobserved heterogeneity among the systems. The heterogeneity is modeled by introduction of unobserved gamma distributed frailties. The relevant likelihood function is derived, and maximum likelihood estimation is illustrated. In a simulation study we then compare results when using a power law model without taking into account heterogeneity, with the corresponding results obtained when the heterogeneity is accounted for. A motivating data example is also given. - Highlights: • Consequences of overlooking heterogeneity in similar repairable systems are studied. • Likelihood functions are established for power law NHPP w/ and w/o heterogeneity. • ML estimators for parameters of power law NHPP with heterogeneity are derived. • A simulation study shows the effects of heterogeneity and its ignorance in models

Power laws from linear neuronal cable theory

DEFF Research Database (Denmark)

Pettersen, Klas H; Lindén, Henrik Anders; Tetzlaff, Tom

2014-01-01

suggested to be at the root of this phenomenon, we here demonstrate a possible origin of such power laws in the biophysical properties of single neurons described by the standard cable equation. Taking advantage of the analytical tractability of the so called ball and stick neuron model, we derive general...... are homogeneously distributed across the neural membranes and themselves exhibit pink ([Formula: see text]) noise distributions. While the PSD noise spectra at low frequencies may be dominated by synaptic noise, our findings suggest that the high-frequency power laws may originate in noise from intrinsic ion...

Human learning: Power laws or multiple characteristic time scales?

Directory of Open Access Journals (Sweden)

Gottfried Mayer-Kress

2006-09-01

Full Text Available The central proposal of A. Newell and Rosenbloom (1981 was that the power law is the ubiquitous law of learning. This proposition is discussed in the context of the key factors that led to the acceptance of the power law as the function of learning. We then outline the principles of an epigenetic landscape framework for considering the role of the characteristic time scales of learning and an approach to system identification of the processes of performance dynamics. In this view, the change of performance over time is the product of a superposition of characteristic exponential time scales that reflect the influence of different processes. This theoretical approach can reproduce the traditional power law of practice – within the experimental resolution of performance data sets - but we hypothesize that this function may prove to be a special and perhaps idealized case of learning.

Effects of viscosity on power and hand injection of iso-osmolar iodinated contrast media through thin catheters.

Science.gov (United States)

Zhang, James J; Hogstrom, Barry; Malinak, Jiri; Ikei, Nobuhiro

2016-05-01

It can be challenging to achieve adequate vessel opacification during percutaneous coronary interventions when using thin catheters, hand injection, and iso-osmolar contrast media (CM) such as iodixanol (Visipaque™). To explore these limitations and the possibility to overcome them with iosimenol, a novel CM. Three X-ray contrast media with different concentrations were used in this study. A series of in vitro experiments established the relationship between injection pressure and flow rate in angiography catheters under various conditions. The experiments were conducted with power and hand injections and included a double-blind evaluation of user perception. By using hand injection, it was generally not possible to reach a maximum injection pressure exceeding 50 psi. The time within which volunteers were able to complete the injections, the area under the pressure-time curve (AUC), and assessment of ease of injection all were in favor of iosimenol compared with iodixanol, especially when using the 4F thin catheter. Within the pressure ranges tested, the power injections demonstrated that the amount of iodine delivered at a fixed pressure was strongly related to viscosity but unrelated to iodine concentration. There are substantial limitations to the amount of iodine that can be delivered through thin catheters by hand injection when iso-osmolar CM with high viscosity is used. The only viable solution, besides increasing the injection pressure, is to use a CM with lower viscosity, since the cost of increasing the concentration, in terms of increased viscosity and consequent reduction in flow, is too high. Iosimenol, an iso-osmolar CM with lower viscosity than iodixanol might therefore be a better alternative when thinner catheters are preferred, especially when the radial artery is used as the access site. © The Foundation Acta Radiologica 2015.

The distance-decay function of geographical gravity model: Power law or exponential law?

International Nuclear Information System (INIS)

Chen, Yanguang

2015-01-01

Highlights: •The distance-decay exponent of the gravity model is a fractal dimension. •Entropy maximization accounts for the gravity model based on power law decay. •Allometric scaling relations relate gravity models with spatial interaction models. •The four-parameter gravity models have dual mathematical expressions. •The inverse power law is the most probable distance-decay function. -- Abstract: The distance-decay function of the geographical gravity model is originally an inverse power law, which suggests a scaling process in spatial interaction. However, the distance exponent of the model cannot be reasonably explained with the ideas from Euclidean geometry. This results in a dimension dilemma in geographical analysis. Consequently, a negative exponential function was used to replace the inverse power function to serve for a distance-decay function. But a new puzzle arose that the exponential-based gravity model goes against the first law of geography. This paper is devoted for solving these kinds of problems by mathematical reasoning and empirical analysis. New findings are as follows. First, the distance exponent of the gravity model is demonstrated to be a fractal dimension using the geometric measure relation. Second, the similarities and differences between the gravity models and spatial interaction models are revealed using allometric relations. Third, a four-parameter gravity model possesses a symmetrical expression, and we need dual gravity models to describe spatial flows. The observational data of China's cities and regions (29 elements indicative of 841 data points) in 2010 are employed to verify the theoretical inferences. A conclusion can be reached that the geographical gravity model based on power-law decay is more suitable for analyzing large, complex, and scale-free regional and urban systems. This study lends further support to the suggestion that the underlying rationale of fractal structure is entropy maximization. Moreover

Exponential and power laws in public procurement markets

Czech Academy of Sciences Publication Activity Database

Krištoufek, Ladislav; Skuhrovec, J.

2012-01-01

Roč. 99, č. 2 (2012), 28005-1-28005-6 ISSN 0295-5075 R&D Projects: GA ČR GA402/09/0965 Grant - others:GA UK(CZ) 118310; SVV(CZ) 265 504; GA TA ČR(CZ) TD010133 Institutional support: RVO:67985556 Keywords : Public procurement * Scaling * Power law Subject RIV: AH - Economics Impact factor: 2.260, year: 2012 http://library.utia.cas.cz/separaty/2012/E/kristoufek-exponential and power laws in public procurement markets.pdf

Power-law versus log-law in wall-bounded turbulence: A large-eddy simulation perspective

KAUST Repository

Cheng, W.; Samtaney, Ravi

2014-01-01

The debate whether the mean streamwise velocity in wall-bounded turbulent flows obeys a log-law or a power-law scaling originated over two decades ago, and continues to ferment in recent years. As experiments and direct numerical simulation can

Refractive index of silica aerogel: Uniformity and dispersion law

International Nuclear Information System (INIS)

Bellunato, T.; Calvi, M.; Matteuzzi, C.; Musy, M.; Perego, D.L.; Storaci, B.

2008-01-01

Two methods for the measurement of the uniformity of the refractive index n within a single block of silica aerogel are described. One is based on the deflection of a laser beam induced by transverse index gradients. The second exploits the Cherenkov effect, measuring the emission angle of photons radiated by 500 MeV electrons traversing the aerogel. The beam can scan the full aerogel surface providing information on point to point variations of n. The measurement of the dispersion law n(λ) is also reported. An Xe lamp coupled to a diffraction grating provides the monochromatic source. The index for each λ is measured by the prism method at a corner of an aerogel sample. A Sellmeier functional form for n(λ) is assumed, and the parameters best fitting the experimental data are given

Stretched exponentials and power laws in granular avalanching

Science.gov (United States)

Head, D. A.; Rodgers, G. J.

1999-02-01

We introduce a model for granular surface flow which exhibits both stretched exponential and power law avalanching over its parameter range. Two modes of transport are incorporated, a rolling layer consisting of individual particles and the overdamped, sliding motion of particle clusters. The crossover in behaviour observed in experiments on piles of rice is attributed to a change in the dominant mode of transport. We predict that power law avalanching will be observed whenever surface flow is dominated by clustered motion.

The Effect of International Trade on Rule of Law

Directory of Open Access Journals (Sweden)

Junsok Yang

2013-03-01

Full Text Available In this paper, we look at the relationship between international trade and the rule of law, using the World Justice Project Rule of Law Index, which include index figures on human rights, limits on government powers, transparency and regulatory efficiency. Based on regression analyses using the rule of law index figures and international trade figures (merchandise trade, service trade, exports and importsIn this paper, we look at the relationship between international trade and the rule of law, using the World Justice Project Rule of Law Index, which include index figures on human rights, limits on government powers, transparency and regulatory efficiency. Based on regression analyses using the rule of law index figures and international trade figures (merchandise trade, service trade, exports and imports as percentage of GDP, international trade and basic human rights seem to have little relationship; but trade has a close positive relationship with strong order and security. Somewhat surprisingly, regulatory transparency and effective implementation seems to have little or no effect on international trade and vice versa. International trade shows a clear positive relationship with the country’s criminal justice system, but the relationship with the civil justice system is not as clear as such. For regulatory implementation and civil justice, services trade positively affect these institutions, but these institutions in turn affect exports more strongly than services trade. Finally, the effect of trade on rule of law is stronger on a medium to long term (10-20 year time horizon.

Power-law thermal model for blackbody sources

International Nuclear Information System (INIS)

Del Grande, N.K.

1979-01-01

The spectral radiant emittance W/sub E/ from a blackbody at a temperature kT for photons at energies E above the spectral peak (2.82144 kT) varies as (kT)/sup E/kT/. This power-law temperature dependence, an approximation of Planck's radiation law, may have applications for measuring the emissivity of sources emitting in the soft x-ray region

KKL correlation for simulation of nanofluid flow and heat transfer in a permeable channel

Energy Technology Data Exchange (ETDEWEB)

Sheikholeslami Kandelousi, Mohsen, E-mail: m_sh_3750@yahoo.com

2014-10-03

Hydrothermal behavior of nanofluid fluid between two parallel plates is studied. One of the plates is externally heated, and the other plate, through which coolant fluid is injected, expands or contracts with time. The effective thermal conductivity and viscosity of nanofluid are calculated by KKL correlation. The effects of the nanoparticle volume fraction, Reynolds number, Expansion ratio and power law index on Hydrothermal behavior are investigated. Results show that heat transfer enhancement has direct relationship with Reynolds number when power law index is equals to zero but opposite trend is observed for other values of power law index. - Highlights: • Nanofluid Hydrothermal behavior in a porous channel is considered. • Nusselt number is an increasing function of ϕ, R and m. • Nusselt number is a decreasing function of α.

Mixed-correlated ARFIMA processes for power-law cross-correlations

Czech Academy of Sciences Publication Activity Database

Krištoufek, Ladislav

2013-01-01

Roč. 392, č. 24 (2013), s. 6484-6493 ISSN 0378-4371 R&D Projects: GA ČR GA402/09/0965 Institutional support: RVO:67985556 Keywords : power-law cross-correlations * long - term memory * econophysics Subject RIV: AH - Economics Impact factor: 1.722, year: 2013 http://library.utia.cas.cz/separaty/2013/E/kristoufek-mixed-correlated arfima processes for power-law cross-correlations.pdf

Mobile user forecast and power-law acceleration invariance of scale-free networks

International Nuclear Information System (INIS)

Guo Jin-Li; Guo Zhao-Hua; Liu Xue-Jiao

2011-01-01

This paper studies and predicts the number growth of China's mobile users by using the power-law regression. We find that the number growth of the mobile users follows a power law. Motivated by the data on the evolution of the mobile users, we consider scenarios of self-organization of accelerating growth networks into scale-free structures and propose a directed network model, in which the nodes grow following a power-law acceleration. The expressions for the transient and the stationary average degree distributions are obtained by using the Poisson process. This result shows that the model generates appropriate power-law connectivity distributions. Therefore, we find a power-law acceleration invariance of the scale-free networks. The numerical simulations of the models agree with the analytical results well. (interdisciplinary physics and related areas of science and technology)

Power-law ansatz in complex systems: Excessive loss of information

Science.gov (United States)

Tsai, Sun-Ting; Chang, Chin-De; Chang, Ching-Hao; Tsai, Meng-Xue; Hsu, Nan-Jung; Hong, Tzay-Ming

2015-12-01

The ubiquity of power-law relations in empirical data displays physicists' love of simple laws and uncovering common causes among seemingly unrelated phenomena. However, many reported power laws lack statistical support and mechanistic backings, not to mention discrepancies with real data are often explained away as corrections due to finite size or other variables. We propose a simple experiment and rigorous statistical procedures to look into these issues. Making use of the fact that the occurrence rate and pulse intensity of crumple sound obey a power law with an exponent that varies with material, we simulate a complex system with two driving mechanisms by crumpling two different sheets together. The probability function of the crumple sound is found to transit from two power-law terms to a bona fide power law as compaction increases. In addition to showing the vicinity of these two distributions in the phase space, this observation nicely demonstrates the effect of interactions to bring about a subtle change in macroscopic behavior and more information may be retrieved if the data are subject to sorting. Our analyses are based on the Akaike information criterion that is a direct measurement of information loss and emphasizes the need to strike a balance between model simplicity and goodness of fit. As a show of force, the Akaike information criterion also found the Gutenberg-Richter law for earthquakes and the scale-free model for a brain functional network, a two-dimensional sandpile, and solar flare intensity to suffer an excessive loss of information. They resemble more the crumpled-together ball at low compactions in that there appear to be two driving mechanisms that take turns occurring.

Power-law ansatz in complex systems: Excessive loss of information.

Science.gov (United States)

Tsai, Sun-Ting; Chang, Chin-De; Chang, Ching-Hao; Tsai, Meng-Xue; Hsu, Nan-Jung; Hong, Tzay-Ming

2015-12-01

The ubiquity of power-law relations in empirical data displays physicists' love of simple laws and uncovering common causes among seemingly unrelated phenomena. However, many reported power laws lack statistical support and mechanistic backings, not to mention discrepancies with real data are often explained away as corrections due to finite size or other variables. We propose a simple experiment and rigorous statistical procedures to look into these issues. Making use of the fact that the occurrence rate and pulse intensity of crumple sound obey a power law with an exponent that varies with material, we simulate a complex system with two driving mechanisms by crumpling two different sheets together. The probability function of the crumple sound is found to transit from two power-law terms to a bona fide power law as compaction increases. In addition to showing the vicinity of these two distributions in the phase space, this observation nicely demonstrates the effect of interactions to bring about a subtle change in macroscopic behavior and more information may be retrieved if the data are subject to sorting. Our analyses are based on the Akaike information criterion that is a direct measurement of information loss and emphasizes the need to strike a balance between model simplicity and goodness of fit. As a show of force, the Akaike information criterion also found the Gutenberg-Richter law for earthquakes and the scale-free model for a brain functional network, a two-dimensional sandpile, and solar flare intensity to suffer an excessive loss of information. They resemble more the crumpled-together ball at low compactions in that there appear to be two driving mechanisms that take turns occurring.

The Normalising Power of Marriage Law: An Irish Genealogy, 1945 – 2010

OpenAIRE

McGowan, Deirdre

2015-01-01

Marriage law is often conceptualised as an instrument of power that illegitimately imposes the will of the State on its citizens. Paradoxically, marriage law is also offered as a route to liberation. In this thesis, I question the efficacy of this type of analysis by investigating the actual power effects of marriage law. Using Michel Foucault’s concepts of bio-power and government, and his genealogical approach to history, I identify the role played by marriage law in governing the social do...

Stable power laws in variable economies; Lotka-Volterra implies Pareto-Zipf

Science.gov (United States)

Solomon, S.; Richmond, P.

2002-05-01

In recent years we have found that logistic systems of the Generalized Lotka-Volterra type (GLV) describing statistical systems of auto-catalytic elements posses power law distributions of the Pareto-Zipf type. In particular, when applied to economic systems, GLV leads to power laws in the relative individual wealth distribution and in market returns. These power laws and their exponent α are invariant to arbitrary variations in the total wealth of the system and to other endogenously and exogenously induced variations.

Consistency relation in power law G-inflation

International Nuclear Information System (INIS)

Unnikrishnan, Sanil; Shankaranarayanan, S.

2014-01-01

In the standard inflationary scenario based on a minimally coupled scalar field, canonical or non-canonical, the subluminal propagation of speed of scalar perturbations ensures the following consistency relation: r ≤ −8n T , where r is the tensor-to-scalar-ratio and n T is the spectral index for tensor perturbations. However, recently, it has been demonstrated that this consistency relation could be violated in Galilean inflation models even in the absence of superluminal propagation of scalar perturbations. It is therefore interesting to investigate whether the subluminal propagation of scalar field perturbations impose any bound on the ratio r/|n T | in G-inflation models. In this paper, we derive the consistency relation for a class of G-inflation models that lead to power law inflation. Within these class of models, it turns out that one can have r > −8n T or r ≤ −8n T depending on the model parameters. However, the subluminal propagation of speed of scalar field perturbations, as required by causality, restricts r ≤ −(32/3) n T

29 CFR 102.35 - Duties and powers of administrative law judges; stipulations of cases to administrative law...

Science.gov (United States)

2010-07-01

..., the judge (or the Board) will decide the case or make other disposition of it. (10) To make and file... 29 Labor 2 2010-07-01 2010-07-01 false Duties and powers of administrative law judges; stipulations of cases to administrative law judges or to the Board; assignment and powers of settlement judges...

Power-Law Statistics of Driven Reconnection in the Magnetically Closed Corona

Science.gov (United States)

Klimchuk, J. A.; DeVore, C. R.; Knizhnik, K. J.; Uritskiy, V. M.

2018-01-01

Numerous observations have revealed that power-law distributions are ubiquitous in energetic solar processes. Hard X-rays, soft X-rays, extreme ultraviolet radiation, and radio waves all display power-law frequency distributions. Since magnetic reconnection is the driving mechanism for many energetic solar phenomena, it is likely that reconnection events themselves display such power-law distributions. In this work, we perform numerical simulations of the solar corona driven by simple convective motions at the photospheric level. Using temperature changes, current distributions, and Poynting fluxes as proxies for heating, we demonstrate that energetic events occurring in our simulation display power-law frequency distributions, with slopes in good agreement with observations. We suggest that the braiding-associated reconnection in the corona can be understood in terms of a self-organized criticality model driven by convective rotational motions similar to those observed at the photosphere.

Power-law Statistics of Driven Reconnection in the Magnetically Closed Corona

Science.gov (United States)

Knizhnik, K. J.; Uritsky, V. M.; Klimchuk, J. A.; DeVore, C. R.

2018-01-01

Numerous observations have revealed that power-law distributions are ubiquitous in energetic solar processes. Hard X-rays, soft X-rays, extreme ultraviolet radiation, and radio waves all display power-law frequency distributions. Since magnetic reconnection is the driving mechanism for many energetic solar phenomena, it is likely that reconnection events themselves display such power-law distributions. In this work, we perform numerical simulations of the solar corona driven by simple convective motions at the photospheric level. Using temperature changes, current distributions, and Poynting fluxes as proxies for heating, we demonstrate that energetic events occurring in our simulation display power-law frequency distributions, with slopes in good agreement with observations. We suggest that the braiding-associated reconnection in the corona can be understood in terms of a self-organized criticality model driven by convective rotational motions similar to those observed at the photosphere.

Power Laws in Stochastic Processes for Social Phenomena: An Introductory Review

Science.gov (United States)

Kumamoto, Shin-Ichiro; Kamihigashi, Takashi

2018-03-01

Many phenomena with power laws have been observed in various fields of the natural and social sciences, and these power laws are often interpreted as the macro behaviors of systems that consist of micro units. In this paper, we review some basic mathematical mechanisms that are known to generate power laws. In particular, we focus on stochastic processes including the Yule process and the Simon process as well as some recent models. The main purpose of this paper is to explain the mathematical details of their mechanisms in a self-contained manner.

Power-law citation distributions are not scale-free.

Science.gov (United States)

Golosovsky, Michael

2017-09-01

We analyze time evolution of statistical distributions of citations to scientific papers published in the same year. While these distributions seem to follow the power-law dependence we find that they are nonstationary and the exponent of the power-law fit decreases with time and does not come to saturation. We attribute the nonstationarity of citation distributions to different longevity of the low-cited and highly cited papers. By measuring citation trajectories of papers we found that citation careers of the low-cited papers come to saturation after 10-15 years while those of the highly cited papers continue to increase indefinitely: The papers that exceed some citation threshold become runaways. Thus, we show that although citation distribution can look as a power-law dependence, it is not scale free and there is a hidden dynamic scale associated with the onset of runaways. We compare our measurements to our recently developed model of citation dynamics based on copying-redirection-triadic closure and find explanations to our empirical observations.

Lack of age-related increase in carotid artery wall viscosity in cardiorespiratory fit men

Science.gov (United States)

Kawano, Hiroshi; Yamamoto, Kenta; Gando, Yuko; Tanimoto, Michiya; Murakami, Haruka; Ohmori, Yumi; Sanada, Kiyoshi; Tabata, Izumi; Higuchi, Mitsuru; Miyachi, Motohiko

2013-01-01

Objectives: Age-related arterial stiffening and reduction of arterial elasticity are attenuated in individuals with high levels of cardiorespiratory fitness. Viscosity is another mechanical characteristic of the arterial wall; however, the effects of age and cardiorespiratory fitness have not been determined. We examined the associations among age, cardiorespiratory fitness and carotid arterial wall viscosity. Methods: A total of 111 healthy men, aged 25–39 years (young) and 40–64 years (middle-aged), were divided into either cardiorespiratory fit or unfit groups on the basis of peak oxygen uptake. The common carotid artery was measured noninvasively by tonometry and automatic tracking of B-mode images to obtain instantaneous pressure and diameter hysteresis loops, and we calculated the effective compliance, isobaric compliance and viscosity index. Results: In the middle-aged men, the viscosity index was larger in the unfit group than in the fit group (2533 vs. 2018 mmHg·s/mm, respectively: P viscosity index was increased with advancing age, but these parameters were unaffected by cardiorespiratory fitness level. Conclusion: These results suggest that the wall viscosity in the central artery is increased with advancing age and that the age-associated increase in wall viscosity may be attenuated in cardiorespiratory fit men. PMID:24029868

Contingency management of power system with Interline Power Flow Controller using Real Power Performance Index and Line Stability Index

Directory of Open Access Journals (Sweden)

Akanksha Mishra

2016-03-01

Full Text Available As a result of privatization of the electrical industry the power transmission lines have to transfer power at their maximum transmission limits because of the competitive scenario of the electrical market. Hence, secured operation of power system has become one of the most important issues of modern era. In this paper, a probability of severity based placement strategy for Interline Power Flow Controller (IPFC has been proposed based on Composite Severity Index (CSI. The composite severity index provides an exact measure of stress in the line in terms of mega watt overloading and voltage instability. IPFC is placed on the line which has the highest probability of severity during the occurrence of different outages. The IPFC has been tuned for a multi-objective function using Differential Evolution (DE and the results have been compared with genetic Algorithm (GA. To verify the proposed method, it has been tested and implemented on IEEE 14 and 57 bus systems.

Uniformity measure for power-law mass spectrum in nuclear fragmentation

International Nuclear Information System (INIS)

Wislicki, W.

1992-11-01

Description is given in terms of the Renyi entropy and the uniformity for the canonical ensemble, the grand canonical ensemble and the power-law probability measures. The study is presented of the power-law spectra of cluster masses observed in nuclear interactions in the vicinity of the liquid-gas transition point. 6 figs., 1 tab., 15 refs. (author)

Concentration dependences of the density, viscosity, and refraction index of Cu(NO3)2 · 3H2O solutions in DMSO at 298 K

Science.gov (United States)

Mamyrbekova, A. K.

2013-03-01

Physicochemical properties (density, dynamic viscosity, refraction index) of the DMSO-Cu(NO3)2 · 3H2O system are studied in the concentration range of 0.01-2 M at 298 K. The refraction index of a solution of copper(II) nitrate in dimethylsulfoxide (DMSO) is measured at 288-318 K. The excess and partial molar volumes of the solvent and dissolved substance are calculated analytically.

Experimental contribution to the understanding of the dynamics of spreading of Newtonian fluids: effect of volume, viscosity and surfactant.

Science.gov (United States)

Roques-Carmes, Thibault; Mathieu, Vincent; Gigante, Alexandra

2010-04-01

The dynamics of drop spreading of glycerol-water mixtures with and without surfactant on hydrophilic glass surfaces has been investigated. The influence of different factors, such as viscosity, drop volume and non-ionic alkyl (8-16) glucoside (Plantacare) surfactant concentration on the number and the nature of the spreading regimes is systematically investigated. More than 25 spreading experiments have been performed in order to obtain clear trends. The results confirm the existence of several spreading regimes for the duration of an experiment (200 s). For each regime, the radius can be expressed by a power law of the form R=Kt(n). Both n and K are necessary to identify the regime. The experimental data are compared with the analytical predictions of the combined theory of spreading. One of the main results of this study is that the nature of the regimes is strongly affected by the drop volume, the viscosity and the surfactant concentration. This behavior is not predicted by the theory. For drop volume less than or equal to 15 microL, a succession of two different regimes which depend on the viscosity and surfactant concentration are observed in the following order: a molecular-kinetic regime followed by a hydrodynamic regime (for high viscosity in the presence of surfactant) or a hydrodynamic regime and lastly a final asymptotic regime corresponding to a long relaxation time to equilibrium (for high viscosity in absence of surfactant and for low viscosity regardless of the presence of surfactant). The spreading follows quantitatively the predictions of the theory. Our results demonstrate that the theory is still valid for low viscosity liquids and in the presence of surfactant. The contact angle for which the crossover between molecular-kinetic regime and hydrodynamic regime occurs is thoroughly estimated since the theories do not allow the exact calculation of this value. Here for the first time, an empirical power law exponent (n=0.08+/-0.05) is proposed for

Nondimensional quasi-steady analysis of magnetorheological dampers utilizing a Herschel-Bulkley model with preyield viscosity

Science.gov (United States)

John, Shaju; Wereley, Norman M.

2003-07-01

Dampers based on electrorheological (ER) and magnetorheolgical (MR) fluids can be analyzed under assumptions of quasi-steady, fully developed flow behavior. Models that have been used to characterize ER and MR dampers include the Bingham-plastic, the Herschel-Bulkley and biviscous models. In the Bingham-plastic and the Herschel-Bulkley models, the fluid exhibits rigid behavior in the preyield flow region. The difference between these two models lie in the modeling of the postyield behavior. In the case of the Bingham-plastic model, the postyield behavior is such that the shear stress is proportional to the shear rate. In contrast, the Herschel-Bulkley model assumes that the shear stress is proportional to a power law of the shearrate. In the biciscous model, the relationship between the shear stres and shear rate is linear in both the preyield and postyield regions with constant values of viscosities for the two regions. However, the preyield flow behavior exhibits a much high viscosity than that in the postyield. In the propose model, the assumption of preyield rigid behavior within the Herschel-Bulkley model has been relaxed while the postyield relationship based on the power law has been retained. Here the fluid undergoes Newtonian preyield viscous flow and has a non-Newtonian postyield behavior. Based on this model, we have analyzed the performance of a rectangular duct ER or MR valve. Typical results include shear stress and velocity profiles across the valve gap, equivalent damping and damping coefficients.

Observational constraints on phantom power-law cosmology

International Nuclear Information System (INIS)

Kaeonikhom, Chakkrit; Gumjudpai, Burin; Saridakis, Emmanuel N.

2011-01-01

We investigate phantom cosmology in which the scale factor is a power law, and we use cosmological observations from Cosmic Microwave Background (CMB), Baryon Acoustic Oscillations (BAO) and observational Hubble data, in order to impose complete constraints on the model parameters. We find that the power-law exponent is β∼-6.51 -0.25 +0.24 , while the Big Rip is realized at t s ∼104.5 -2.0 +1.9 Gyr, in 1σ confidence level. Providing late-time asymptotic expressions, we find that the dark-energy equation-of-state parameter at the Big Rip remains finite and equal to w DE ∼-1.153, with the dark-energy density and pressure diverging. Finally, we reconstruct the phantom potential.

Dynamic intersectoral models with power-law memory

Science.gov (United States)

Tarasova, Valentina V.; Tarasov, Vasily E.

2018-01-01

Intersectoral dynamic models with power-law memory are proposed. The equations of open and closed intersectoral models, in which the memory effects are described by the Caputo derivatives of non-integer orders, are derived. We suggest solutions of these equations, which have the form of linear combinations of the Mittag-Leffler functions and which are characterized by different effective growth rates. Examples of intersectoral dynamics with power-law memory are suggested for two sectoral cases. We formulate two principles of intersectoral dynamics with memory: the principle of changing of technological growth rates and the principle of domination change. It has been shown that in the input-output economic dynamics the effects of fading memory can change the economic growth rate and dominant behavior of economic sectors.

Variational principle for the Pareto power law.

Science.gov (United States)

Chakraborti, Anirban; Patriarca, Marco

2009-11-27

A mechanism is proposed for the appearance of power-law distributions in various complex systems. It is shown that in a conservative mechanical system composed of subsystems with different numbers of degrees of freedom a robust power-law tail can appear in the equilibrium distribution of energy as a result of certain superpositions of the canonical equilibrium energy densities of the subsystems. The derivation only uses a variational principle based on the Boltzmann entropy, without assumptions outside the framework of canonical equilibrium statistical mechanics. Two examples are discussed, free diffusion on a complex network and a kinetic model of wealth exchange. The mechanism is illustrated in the general case through an exactly solvable mechanical model of a dimensionally heterogeneous system.

Body fat and blood rheology: Evaluation of the association between different adiposity indices and blood viscosity.

Science.gov (United States)

Tripolino, Cesare; Irace, Concetta; Carallo, Claudio; Scavelli, Faustina Barbara; Gnasso, Agostino

2017-01-01

In recent years, new measures of body adiposity have been introduced: lipid accumulation product (LAP), body adiposity index (BAI) and body shape index (ABSI). These indices have been demonstrated to better associate with cardiovascular disease than other measures of adiposity. The aim of the present study was to evaluate if LAP or BAI better associate with blood viscosity than other measures of adiposity (body mass index, BMI; waist circumference, WC; waist-to-hip ratio, W/HR; waist-to-height ratio, W/HtR). 344 subjects were recruited for the present investigation. Exclusion criteria were: diabetes, elevated triglycerides, smoking and drug use. Blood lipids and glucose were measured by routine methods. Blood and plasma viscosity were measured by a cone-plate viscometer. Adiposity measures were computed as previously described. In simple correlation analyses, blood viscosity (BV) correlated with BMI, BAI, and LAP in males and with LAP in females. Correlations between plasma viscosity and adiposity indices were weak and not statistically significant. Other variables significantly related with BV were: gender, HDL- and LDL-Cholesterol, and triglycerides (p index is strongly associated to blood viscosity. This result, along with previous evidence, identifies LAP index as a potential cardiovascular risk marker.

Exploring the effect of power law social popularity on language evolution.

Science.gov (United States)

Gong, Tao; Shuai, Lan

2014-01-01

We evaluate the effect of a power-law-distributed social popularity on the origin and change of language, based on three artificial life models meticulously tracing the evolution of linguistic conventions including lexical items, categories, and simple syntax. A cross-model analysis reveals an optimal social popularity, in which the λ value of the power law distribution is around 1.0. Under this scaling, linguistic conventions can efficiently emerge and widely diffuse among individuals, thus maintaining a useful level of mutual understandability even in a big population. From an evolutionary perspective, we regard this social optimality as a tradeoff among social scaling, mutual understandability, and population growth. Empirical evidence confirms that such optimal power laws exist in many large-scale social systems that are constructed primarily via language-related interactions. This study contributes to the empirical explorations and theoretical discussions of the evolutionary relations between ubiquitous power laws in social systems and relevant individual behaviors.

Chebyshev super spectral viscosity method for a fluidized bed model

International Nuclear Information System (INIS)

Sarra, Scott A.

2003-01-01

A Chebyshev super spectral viscosity method and operator splitting are used to solve a hyperbolic system of conservation laws with a source term modeling a fluidized bed. The fluidized bed displays a slugging behavior which corresponds to shocks in the solution. A modified Gegenbauer postprocessing procedure is used to obtain a solution which is free of oscillations caused by the Gibbs-Wilbraham phenomenon in the spectral viscosity solution. Conservation is maintained by working with unphysical negative particle concentrations

Simple model for the power-law blinking of single semiconductor nanocrystals

NARCIS (Netherlands)

Verberk, Rogier; Oijen, Antoine M. van; Orrit, Michel

2002-01-01

We assign the blinking of nanocrystals to electron tunneling towards a uniform spatial distribution of traps. This naturally explains the power-law distribution of off times, and the power-law correlation function we measured on uncapped CdS dots. Capped dots, on the other hand, present extended on

Power Distance and Verbal Index in Kazakh Business Discourse

Directory of Open Access Journals (Sweden)

Buadat Karibayeva

2017-01-01

Full Text Available Kazakh business discourse is a relatively new area for research, and hence many of the cultural preferences are yet to be explored. This paper focuses on measuring Hofstede’s power distance index for Kazakh culture. A novel technique is proposed, where verbal index is calculated from analysis of publically available texts delivered by representatives of different cultures. In particular, we analyzed public speeches delivered by leaders ofNew Zealand,UK,Germany,Australia,USA,Greece,China,India, andKazakhstan. From these texts we derived a verbal index, which closely correlated to Hofstede’s power distance data. As a result, we were able to obtain a power distance index of 58 forKazakhstan, which was previously unavailable in literature. Furthermore, this method can be used as a cheaper alternative to conducting surveys in estimating Hofstede’s power distance indexes for different cultures.

Regulatory Powers in Public Procurement Law of Peruvian Administrative Agencies

Directory of Open Access Journals (Sweden)

Juan Carlos Morón Urbina

2017-12-01

Full Text Available Peruvian law has explicitly recognized regulatory powers to administrative agencies, which allows them to have a preponderant role in the production of rules in public procurement. Although these delegations of legislative authority are positively defined, distortions in the system of legal sources arise when agencies exceed delegated powers or when measures issued by administrative entities are mistaken for regulations. This paper aims to identify regulatory powers of Peruvian administrative agencies, as well as the regulatory measures they issue, and their relation with other sources of law.

Whole-blood viscosity and the insulin-resistance syndrome.

Science.gov (United States)

Høieggen, A; Fossum, E; Moan, A; Enger, E; Kjeldsen, S E

1998-02-01

In a previous study we found that elevated blood viscosity was linked to the insulin resistance syndrome, and we proposed that high blood viscosity may increase insulin resistance. That study was based on calculated viscosity. To determine whether directly measured whole-blood viscosity was related to the insulin-resistance syndrome in the same way as calculated viscosity had been found to be. Healthy young men were examined with the hyperinsulinemic isoglycemic glucose clamp technique, and we related insulin sensitivity (glucose disposal rate) to other metabolic parameters and to blood viscosity. We established a technique for direct measurement of whole-blood viscosity. There were statistically significant negative correlations between glucose disposal rate and whole-blood viscosity at low and high shear rates (r = -0.41, P = 0.007 for both, n = 42). Whole-blood viscosity was correlated positively (n = 15) to serum triglyceride (r = 0.54, P = 0.04) and total cholesterol (r = 0.52, P = 0.05), and negatively with high-density lipoprotein cholesterol (r = -0.53, P = 0.04) concentrations. Insulin sensitivity index was correlated positively to high-density lipoprotein cholesterol (r = 0.54, P = 0.04) and negatively to serum triglyceride (r = -0.69, P = 0.005) and to total cholesterol (r = -0.81, P = 0.0003) concentrations. The present results demonstrate for the first time that there is a negative relationship between directly measured whole-blood viscosity and insulin sensitivity as a part of the insulin-resistance syndrome. Whole-blood viscosity contributes to the total peripheral resistance, and these results support the hypothesis that insulin resistance has a hemodynamic basis.

Transport coefficients in Lorentz plasmas with the power-law kappa-distribution

International Nuclear Information System (INIS)

Jiulin, Du

2013-01-01

Transport coefficients in Lorentz plasma with the power-law κ-distribution are studied by means of using the transport equation and macroscopic laws of Lorentz plasma without magnetic field. Expressions of electric conductivity, thermoelectric coefficient, and thermal conductivity for the power-law κ-distribution are accurately derived. It is shown that these transport coefficients are significantly modified by the κ-parameter, and in the limit of the parameter κ→∞ they are reduced to the standard forms for a Maxwellian distribution

A comparative study of high-viscosity cement percutaneous vertebroplasty vs. low-viscosity cement percutaneous kyphoplasty for treatment of osteoporotic vertebral compression fractures.

Science.gov (United States)

Sun, Kai; Liu, Yang; Peng, Hao; Tan, Jun-Feng; Zhang, Mi; Zheng, Xian-Nian; Chen, Fang-Zhou; Li, Ming-Hui

2016-06-01

The clinical effects of two different methods-high-viscosity cement percutaneous vertebroplasty (PVP) and low-viscosity cement percutaneous kyphoplasty (PKP) in the treatment of osteoporotic vertebral compression fractures (OVCFs) were investigated. From June 2010 to August 2013, 98 cases of OVCFs were included in our study. Forty-six patients underwent high-viscosity PVP and 52 patients underwent low-viscosity PKP. The occurrence of cement leakage was observed. Pain relief and functional activity were evaluated using the Visual Analog Scale (VAS) and Oswestry Disability Index (ODI), respectively. Restoration of the vertebral body height and angle of kyphosis were assessed by comparing preoperative and postoperative measurements of the anterior heights, middle heights and the kyphotic angle of the fractured vertebra. Nine out of the 54 vertebra bodies and 11 out of the 60 vertebra bodies were observed to have cement leakage in the high-viscosity PVP and low-viscosity PKP groups, respectively. The rate of cement leakage, correction of anterior vertebral height and kyphotic angles showed no significant differences between the two groups (P>0.05). Low-viscosity PKP had significant advantage in terms of the restoration of middle vertebral height as compared with the high-viscosity PVP (Pviscosity PVP and low-viscosity PKP have similar clinical effects in terms of the rate of cement leakage, restoration of the anterior vertebral body height, changes of kyphotic angles, functional activity, and pain relief. Low-viscosity PKP is better than high-viscosity PVP in restoring the height of the middle vertebra.

Predicting the long tail of book sales: Unearthing the power-law exponent

Science.gov (United States)

Fenner, Trevor; Levene, Mark; Loizou, George

2010-06-01

The concept of the long tail has recently been used to explain the phenomenon in e-commerce where the total volume of sales of the items in the tail is comparable to that of the most popular items. In the case of online book sales, the proportion of tail sales has been estimated using regression techniques on the assumption that the data obeys a power-law distribution. Here we propose a different technique for estimation based on a generative model of book sales that results in an asymptotic power-law distribution of sales, but which does not suffer from the problems related to power-law regression techniques. We show that the proportion of tail sales predicted is very sensitive to the estimated power-law exponent. In particular, if we assume that the power-law exponent of the cumulative distribution is closer to 1.1 rather than to 1.2 (estimates published in 2003, calculated using regression by two groups of researchers), then our computations suggest that the tail sales of Amazon.com, rather than being 40% as estimated by Brynjolfsson, Hu and Smith in 2003, are actually closer to 20%, the proportion estimated by its CEO.

On the power law of passive scalars in turbulence

Science.gov (United States)

Gotoh, Toshiyuki; Watanabe, Takeshi

2015-11-01

It has long been considered that the moments of the scalar increment with separation distance r obey power law with scaling exponents in the inertial convective range and the exponents are insensitive to variation of pumping of scalar fluctuations at large scales, thus the scaling exponents are universal. We examine the scaling behavior of the moments of increments of passive scalars 1 and 2 by using DNS up to the grid points of 40963. They are simultaneously convected by the same isotropic steady turbulence atRλ = 805 , but excited by two different methods. Scalar 1 is excited by the random scalar injection which is isotropic, Gaussian and white in time at law wavenumber band, while Scalar 2 is excited by the uniform mean scalar gradient. It is found that the local scaling exponents of the scalar 1 has a logarithmic correction, meaning that the moments of the scalar 1 do not obey simple power law. On the other hand, the moments of the scalar 2 is found to obey the well developed power law with exponents consistent with those in the literature. Physical reasons for the difference are explored. Grants-in-Aid for Scientific Research 15H02218 and 26420106, NIFS14KNSS050, HPCI project hp150088 and hp140024, JHPCN project jh150012.

Spatial variation of AIA coronal Fourier power spectra

Science.gov (United States)

Ireland, J.; Mcateer, R. T. J.

2015-12-01

We describe a study of the spatial distribution of the properties of the Fourier power spectrum of time-series of AIA 171Å and 193Å data. The area studied includes examples of physically different components of the corona, such as coronal moss, a sunspot, quiet Sun and fan loop footpoints. We show that a large fraction of the power spectra are well modeled by a power spectrum that behaves like a power law f-n (n>0)at lower frequencies f, dropping to a constant value at higher frequencies. We also show that there are areas where the power spectra are better described by the above power spectrum model, plus a narrow band oscillatory feature, centered in the 3-5 minute oscillation range. These narrow-band spectral features are thought to be due to the propagation of oscillations from lower down in solar atmosphere to hotter. This allows us to produce maps of large areas of the corona showing where the propagation from one waveband to another does and does not occur. This is an important step in understanding wave propagation in different layers in the corona. We also show the 171Å and 193Å power spectrum power law indices are correlated, with 171Å power law indices in the range n = 1.8 to 2.8, and 193Å power law indices n = 2 to 3.5 approximately. Maps of the power law index show that different ranges of values of the power law indices occur in spatially contiguous parts of the corona, indicating that local spatial structure may play a role in defining the power law index value. Taken with our previous result from Ireland et al. (2015) that physically different parts of the corona have different mean values of the power law index, this new result strongly suggests that the same mechanism producing the observed power law power spectrum is operating everywhere across the corona. We discuss the nanoflare hypothesis as a possible explanation of these observations.

A theory of power-law distributions in financial market fluctuations.

Science.gov (United States)

Gabaix, Xavier; Gopikrishnan, Parameswaran; Plerou, Vasiliki; Stanley, H Eugene

2003-05-15

Insights into the dynamics of a complex system are often gained by focusing on large fluctuations. For the financial system, huge databases now exist that facilitate the analysis of large fluctuations and the characterization of their statistical behaviour. Power laws appear to describe histograms of relevant financial fluctuations, such as fluctuations in stock price, trading volume and the number of trades. Surprisingly, the exponents that characterize these power laws are similar for different types and sizes of markets, for different market trends and even for different countries--suggesting that a generic theoretical basis may underlie these phenomena. Here we propose a model, based on a plausible set of assumptions, which provides an explanation for these empirical power laws. Our model is based on the hypothesis that large movements in stock market activity arise from the trades of large participants. Starting from an empirical characterization of the size distribution of those large market participants (mutual funds), we show that the power laws observed in financial data arise when the trading behaviour is performed in an optimal way. Our model additionally explains certain striking empirical regularities that describe the relationship between large fluctuations in prices, trading volume and the number of trades.

Index-based reactive power compensation scheme for voltage regulation

Science.gov (United States)

Dike, Damian Obioma

2008-10-01

Increasing demand for electrical power arising from deregulation and the restrictions posed to the construction of new transmission lines by environment, socioeconomic, and political issues had led to higher grid loading. Consequently, voltage instability has become a major concern, and reactive power support is vital to enhance transmission grid performance. Improved reactive power support to distressed grid is possible through the application of relatively unfamiliar emerging technologies of "Flexible AC Transmission Systems (FACTS)" devices and "Distributed Energy Resources (DERS)." In addition to these infrastructure issues, a lack of situational awareness by system operators can cause major power outages as evidenced by the August 14, 2003 widespread North American blackout. This and many other recent major outages have highlighted the inadequacies of existing power system indexes. In this work, a novel "Index-based reactive compensation scheme" appropriate for both on-line and off-line computation of grid status has been developed. A new voltage stability index (Ls-index) suitable for long transmission lines was developed, simulated, and compared to the existing two-machine modeled L-index. This showed the effect of long distance power wheeling amongst regional transmission organizations. The dissertation further provided models for index modulated voltage source converters (VSC) and index-based load flow analysis of both FACTS and microgrid interconnected power systems using the Newton-Raphson's load flow model incorporated with multi-FACTS devices. The developed package has been made user-friendly through the embodiment of interactive graphical user interface and implemented on the IEEE 14, 30, and 300 bus systems. The results showed reactive compensation has system wide-effect, provided readily accessible system status indicators, ensured seamless DERs interconnection through new islanding modes and enhanced VSC utilization. These outcomes may contribute

Strong Law of Large Numbers for Hidden Markov Chains Indexed by an Infinite Tree with Uniformly Bounded Degrees

Directory of Open Access Journals (Sweden)

Huilin Huang

2014-01-01

Full Text Available We study strong limit theorems for hidden Markov chains fields indexed by an infinite tree with uniformly bounded degrees. We mainly establish the strong law of large numbers for hidden Markov chains fields indexed by an infinite tree with uniformly bounded degrees and give the strong limit law of the conditional sample entropy rate.

Dynamics of warm power-law plateau inflation with a generalized inflaton decay rate: predictions and constraints after Planck 2015

Energy Technology Data Exchange (ETDEWEB)

Jawad, Abdul [COMSATS Institute of Information Technology, Department of Mathematics, Lahore (Pakistan); Videla, Nelson [FCFM, Universidad de Chile, Departamento de Fisica, Santiago (Chile); Gulshan, Faiza [Lahore Leads University, Department of Mathematics, Lahore (Pakistan)

2017-05-15

In the present work, we study the consequences of considering a new family of single-field inflation models, called power-law plateau inflation, in the warm inflation framework. We consider the inflationary expansion is driven by a standard scalar field with a decay ratio Γ having a generic power-law dependence with the scalar field φ and the temperature of the thermal bath T given by Γ(φ,T) = C{sub φ}(T{sup a})/(φ{sup a-1}). Assuming that our model evolves according to the strong dissipative regime, we study the background and perturbative dynamics, obtaining the most relevant inflationary observable as the scalar power spectrum, the scalar spectral index and its running and the tensor-to-scalar ratio. The free parameters characterizing our model are constrained by considering the essential condition for warm inflation, the conditions for the model evolves according to the strong dissipative regime and the 2015 Planck results through the n{sub s}-r plane. For completeness, we study the predictions in the n{sub s}-dn{sub s}/d ln k plane. The model is consistent with a strong dissipative dynamics and predicts values for the tensor-to-scalar ratio and for the running of the scalar spectral index consistent with current bounds imposed by Planck and we conclude that the model is viable. (orig.)

Dynamics of warm power-law plateau inflation with a generalized inflaton decay rate: predictions and constraints after Planck 2015

International Nuclear Information System (INIS)

Jawad, Abdul; Videla, Nelson; Gulshan, Faiza

2017-01-01

In the present work, we study the consequences of considering a new family of single-field inflation models, called power-law plateau inflation, in the warm inflation framework. We consider the inflationary expansion is driven by a standard scalar field with a decay ratio Γ having a generic power-law dependence with the scalar field φ and the temperature of the thermal bath T given by Γ(φ,T) = C_φ(T"a)/(φ"a"-"1). Assuming that our model evolves according to the strong dissipative regime, we study the background and perturbative dynamics, obtaining the most relevant inflationary observable as the scalar power spectrum, the scalar spectral index and its running and the tensor-to-scalar ratio. The free parameters characterizing our model are constrained by considering the essential condition for warm inflation, the conditions for the model evolves according to the strong dissipative regime and the 2015 Planck results through the n_s-r plane. For completeness, we study the predictions in the n_s-dn_s/d ln k plane. The model is consistent with a strong dissipative dynamics and predicts values for the tensor-to-scalar ratio and for the running of the scalar spectral index consistent with current bounds imposed by Planck and we conclude that the model is viable. (orig.)

Tunable power law in the desynchronization events of coupled chaotic electronic circuits

International Nuclear Information System (INIS)

Oliveira, Gilson F. de; Lorenzo, Orlando di; Chevrollier, Martine; Passerat de Silans, Thierry; Oriá, Marcos; Souza Cavalcante, Hugo L. D. de

2014-01-01

We study the statistics of the amplitude of the synchronization error in chaotic electronic circuits coupled through linear feedback. Depending on the coupling strength, our system exhibits three qualitatively different regimes of synchronization: weak coupling yields independent oscillations; moderate to strong coupling produces a regime of intermittent synchronization known as attractor bubbling; and stronger coupling produces complete synchronization. In the regime of moderate coupling, the probability distribution for the sizes of desynchronization events follows a power law, with an exponent that can be adjusted by changing the coupling strength. Such power-law distributions are interesting, as they appear in many complex systems. However, most of the systems with such a behavior have a fixed value for the exponent of the power law, while here we present an example of a system where the exponent of the power law is easily tuned in real time

Implementation of the entropy viscosity method with the discontinuous Galerkin method

KAUST Repository

Zingan, Valentin

2013-01-01

The notion of entropy viscosity method introduced in Guermond and Pasquetti [21] is extended to the discontinuous Galerkin framework for scalar conservation laws and the compressible Euler equations. © 2012 Elsevier B.V.

Preliminary limits on deviation from the inverse-square law of gravity in the solar system: a power-law parameterization

International Nuclear Information System (INIS)

Liu Meng-Yao; Zhong Ze-Hao; Han Yi-Chen; Wang Xiao-Yu; Yang Zong-Shui; Xie Yi

2014-01-01

New physics beyond the standard model of particles might cause a deviation from the inverse-square law of gravity. In some theories, it is parameterized by a power-law correction to the Newtonian gravitational force, which might originate from the simultaneous exchange of particles or modified and extended theories of gravity. Using the supplementary advances of the perihelia provided by INPOP10a (IMCCE, France) and EPM2011 (IAA RAS, Russia) ephemerides, we obtain preliminary limits on this correction. In our estimation, we take the Lense-Thirring effect due to the Sun's angular momentum into account. The parameters of the power-law correction and the uncertainty of the Sun's quadrupole moment are simultaneously estimated with the method of minimizing χ 2 . From INPOP10a, we find N = 0.605 for the exponent of the power-law correction. However, from EPM2011, we find that, although it yields N = 3.001, the estimated uncertainty in the Sun's quadrupole moment is much larger than the value given by current observations. This might be caused by the intrinsic nonlinearity in the power-law correction, which makes the estimation very sensitive to the supplementary advances of the perihelia. (research papers)

Pascal (Yang Hui) triangles and power laws in the logistic map

International Nuclear Information System (INIS)

Velarde, Carlos; Robledo, Alberto

2015-01-01

We point out the joint occurrence of Pascal triangle patterns and power-law scaling in the standard logistic map, or more generally, in unimodal maps. It is known that these features are present in its two types of bifurcation cascades: period and chaotic-band doubling of attractors. Approximate Pascal triangles are exhibited by the sets of lengths of supercycle diameters and by the sets of widths of opening bands. Additionally, power-law scaling manifests along periodic attractor supercycle positions and chaotic band splitting points. Consequently, the attractor at the mutual accumulation point of the doubling cascades, the onset of chaos, displays both Gaussian and power-law distributions. Their combined existence implies both ordinary and exceptional statistical-mechanical descriptions of dynamical properties. (paper)

Energy consumption reduction in existing HVAC-R systems via a power law controlling kit

International Nuclear Information System (INIS)

Pinnola, C.F.; Vargas, J.V.C.; Buiar, C.L.; Ordonez, J.C.

2015-01-01

This paper presents an alternative solution for reducing energy consumption in heating, ventilation, air conditioning and refrigeration (HVAC-R) systems. For that, an existing typical commercial refrigeration system was equipped with a novel control system based on a power law, using a frequency inverter and a programmable logic controller (PLC). Hence, it was possible to compare the operation and energy consumption of the system with the power law control and with the on-off system, quantifying the obtained gains. The experimental unit consisted of a cooling chamber, an enclosing chamber (antechamber), and a vapor compression refrigeration system, i.e., an example of a practical commercial cooling system. A set of graphs shows the experimental measurements performed with the two systems. In this way, the measured temperatures in some selected points of the two systems, as well as the consumption in kWh for a period of 6 h and 10 min were compared in the tests. The main conclusions of this work are: i) The system operating with the power law control with respect to the conventional on-off control, showed energy consumption savings of up to 31% in a test period of 6 h and 10 min, and ii) The system compressor cycling frequency in the system operating with the power law control is smaller than with the traditional on-off system. Therefore, the study shows that the developed power law control kit has potential to be installed in any existing system with immediate significant energy savings with no need for HVAC-R hardware changes. - Highlights: • An energy consumption reduction strategy for HVAC-R systems is presented. • Power law and on-off control actions are experimentally compared. • Energy savings of 31% were obtained with power law control. • Compressor cycling frequency is smaller with power law control. • Power law control kit has potential to be installed in any existing system

Proposed law concerning the phase-out of nuclear power

International Nuclear Information System (INIS)

1997-01-01

This Government bill that will be presented to the Swedish Parliament, gives the Government the right to revoke the licence of operating a nuclear power plant at a certain time. The operator is given the right to a financial compensation when the licence is revoked, in line with the rules in the expropriation laws. Safety aspects of operation of nuclear installations are not regulated in this law, i.e. the law can not be used when the operating licence is revoked due to safety reasons

Poissonian renormalizations, exponentials, and power laws.

Science.gov (United States)

Eliazar, Iddo

2013-05-01

This paper presents a comprehensive "renormalization study" of Poisson processes governed by exponential and power-law intensities. These Poisson processes are of fundamental importance, as they constitute the very bedrock of the universal extreme-value laws of Gumbel, Fréchet, and Weibull. Applying the method of Poissonian renormalization we analyze the emergence of these Poisson processes, unveil their intrinsic dynamical structures, determine their domains of attraction, and characterize their structural phase transitions. These structural phase transitions are shown to be governed by uniform and harmonic intensities, to have universal domains of attraction, to uniquely display intrinsic invariance, and to be intimately connected to "white noise" and to "1/f noise." Thus, we establish a Poissonian explanation to the omnipresence of white and 1/f noises.

Evaluation of 'period-generated' control laws for the time-optimal control of reactor power

International Nuclear Information System (INIS)

Bernard, J.A.

1988-01-01

Time-Optimal control of neutronic power has recently been achieved by developing control laws that determine the actuator mechanism velocity necessary to produce a specified reactor period. These laws are designated as the 'MIT-SNL Period-Generated Minimum Time Control Laws'. Relative to time-optimal response, they function by altering the rate of change of reactivity so that the instantaneous period is stepped from infinity to its minimum allowed value, held at that value until the desired power level is attained, and then stepped back to infinity. The results of a systematic evaluation of these laws are presented. The behavior of each term in the control laws is shown and the capability of these laws to control properly the reactor power is demonstrated. Factors affecting the implementation of these laws, such as the prompt neutron lifetime and the differential reactivity worth of the actuators, are discussed. Finally, the results of an experimental study in which these laws were used to adjust the power of the 5 MWt MIT Research Reactor are shown. The information presented should be of interest to those designing high performance control systems for test, spacecraft, or, in certain instances, commercial reactors

COSMOLOGY OF CHAMELEONS WITH POWER-LAW COUPLINGS

International Nuclear Information System (INIS)

Mota, David F.; Winther, Hans A.

2011-01-01

In chameleon field theories, a scalar field can couple to matter with gravitational strength and still evade local gravity constraints due to a combination of self-interactions and the couplings to matter. Originally, these theories were proposed with a constant coupling to matter; however, the chameleon mechanism also extends to the case where the coupling becomes field dependent. We study the cosmology of chameleon models with power-law couplings and power-law potentials. It is found that these generalized chameleons, when viable, have a background expansion very close to ΛCDM, but can in some special cases enhance the growth of the linear perturbations at low redshifts. For the models we consider, it is found that this region of the parameter space is ruled out by local gravity constraints. Imposing a coupling to dark matter only, the local constraints are avoided, and it is possible to have observable signatures on the linear matter perturbations.

Constraints on the tensor-to-scalar ratio for non-power-law models

International Nuclear Information System (INIS)

Vázquez, J. Alberto; Bridges, M.; Ma, Yin-Zhe; Hobson, M.P.

2013-01-01

Recent cosmological observations hint at a deviation from the simple power-law form of the primordial spectrum of curvature perturbations. In this paper we show that in the presence of a tensor component, a turn-over in the initial spectrum is preferred by current observations, and hence non-power-law models ought to be considered. For instance, for a power-law parameterisation with both a tensor component and running parameter, current data show a preference for a negative running at more than 2.5σ C.L. As a consequence of this deviation from a power-law, constraints on the tensor-to-scalar ratio r are slightly broader. We also present constraints on the inflationary parameters for a model-independent reconstruction and the Lasenby and Doran (LD) model. In particular, the constraints on the tensor-to-scalar ratio from the LD model are: r LD = 0.11±0.024. In addition to current data, we show expected constraints from Planck-like and CMB-Pol sensitivity experiments by using Markov-Chain-Monte-Carlo sampling chains. For all the models, we have included the Bayesian Evidence to perform a model selection analysis. The Bayes factor, using current observations, shows a strong preference for the LD model over the standard power-law parameterisation, and provides an insight into the accuracy of differentiating models through future surveys

The relationship between blood viscosity and blood pressure in a random sample of the population aged 55 to 74 years.

Science.gov (United States)

Fowkes, F G; Lowe, G D; Rumley, A; Lennie, S E; Smith, F B; Donnan, P T

1993-05-01

Blood viscosity is elevated in hypertensive subjects, but the association of viscosity with arterial blood pressure in the general population, and the influence of social, lifestyle and disease characteristics on this association, are not established. In the Edinburgh Artery Study, 1592 men and women aged 55-74 years selected randomly from the general population attended a university clinic. A fasting blood sample was taken for the measurement of blood viscosity and its major determinants (haematocrit, plasma viscosity and fibrinogen). Systolic pressure was related univariately to blood viscosity (P viscosity (P index. Diastolic pressure was related univariately to blood viscosity (P viscosity (P viscosity and systolic pressure was confined to males. Blood viscosity was associated equally with systolic and diastolic pressures in males, and remained independently related on multivariate analysis adjusting for age, sex, body mass index, social class, smoking, alcohol intake, exercise, angina, HDL and non-HDL cholesterol, diabetes mellitus, plasma viscosity, fibrinogen, and haematocrit.

Agreements concluded by the Federal Republic of Germany under international law in the field of environmental protection. Annex: Treaties with the GDR. (Source index in the Federal Law Gazette, part II). (As of September 15, 1987)

International Nuclear Information System (INIS)

Lohse, S.

1987-01-01

This compilation contains all agreements under international law in the field of environmental protection, the FRG has joined and that have been published and/or announced in the Federal Law Gazette, part II. The summary is of September 15, 1987. The classification is made according to the subjects: waste management law, pollution abatement law, nuclear law and energy and mining law and within these according to the date of treaty/agreement. For easier access, there are a chronological index, an index of the contracting states and an index of the places of contract. In the annex the relevant treaties with the German Democratic Republic are indicated. (orig./HP) [de

Dual plane problems for creeping flow of power-law incompressible medium

Directory of Open Access Journals (Sweden)

Dmitriy S. Petukhov

2016-09-01

Full Text Available In this paper, we consider the class of solutions for a creeping plane flow of incompressible medium with power-law rheology, which are written in the form of the product of arbitrary power of the radial coordinate by arbitrary function of the angular coordinate of the polar coordinate system covering the plane. This class of solutions represents the asymptotics of fields in the vicinity of singular points in the domain occupied by the examined medium. We have ascertained the duality of two problems for a plane with wedge-shaped notch, at which boundaries in one of the problems the vector components of the surface force vanish, while in the other—the vanishing components are the vector components of velocity, We have investigated the asymptotics and eigensolutions of the dual nonlinear eigenvalue problems in relation to the rheological exponent and opening angle of the notch for the branch associated with the eigenvalue of the Hutchinson–Rice–Rosengren problem learned from the problem of stress distribution over a notched plane for a power law medium. In the context of the dual problem we have determined the velocity distribution in the flow of power-law medium at the vertex of a rigid wedge, We have also found another two eigenvalues, one of which was determined by V. V. Sokolovsky for the problem of power-law fluid flow in a convergent channel.

Empirical Scaling Laws of Neutral Beam Injection Power in HL-2A Tokamak

International Nuclear Information System (INIS)

Cao Jian-Yong; Wei Hui-Ling; Liu He; Yang Xian-Fu; Zou Gui-Qing; Yu Li-Ming; Li Qing; Luo Cui-Wen; Pan Yu-Dong; Jiang Shao-Feng; Lei Guang-Jiu; Li Bo; Rao Jun; Duan Xu-Ru

2015-01-01

We present an experimental method to obtain neutral beam injection (NBI) power scaling laws with operating parameters of the NBI system on HL-2A, including the beam divergence angle, the beam power transmission efficiency, the neutralization efficiency and so on. With the empirical scaling laws, the estimating power can be obtained in every shot of experiment on time, therefore the important parameters such as the energy confinement time can be obtained precisely. The simulation results by the tokamak simulation code (TSC) show that the evolution of the plasma parameters is in good agreement with the experimental results by using the NBI power from the empirical scaling law. (paper)

Mathematical modeling for laminar flow of power law fluid in porous media

Energy Technology Data Exchange (ETDEWEB)

Silva, Renato A.; Mesquita, Maximilian S. [Universidade Federal do Espirito Santo (UFES), Sao Mateus, ES (Brazil). Centro Universitario Norte do Espirito Santo. Dept. de Engenharias e Computacao

2010-07-01

In this paper, the macroscopic equations for laminar power-law fluid flow is obtained for a porous medium starting from traditional equations (Navier-Stokes). Then, the volume averaging is applied in traditional transport equations with the power-law fluid model. This procedure leads to macroscopic transport equations set for non-Newtonian fluid. (author)

A common mode of origin of power laws in models of market and earthquake

Science.gov (United States)

Bhattacharyya, Pratip; Chatterjee, Arnab; Chakrabarti, Bikas K.

2007-07-01

We show that there is a common mode of origin for the power laws observed in two different models: (i) the Pareto law for the distribution of money among the agents with random-saving propensities in an ideal gas-like market model and (ii) the Gutenberg-Richter law for the distribution of overlaps in a fractal-overlap model for earthquakes. We find that the power laws appear as the asymptotic forms of ever-widening log-normal distributions for the agents’ money and the overlap magnitude, respectively. The identification of the generic origin of the power laws helps in better understanding and in developing generalized views of phenomena in such diverse areas as economics and geophysics.

Modified Thermoresponsive Hyperbranched Polymers for Improved Viscosity and Enhanced Lubricity of Engine Oils

Energy Technology Data Exchange (ETDEWEB)

Cosimbescu, Lelia [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Robinson, Joshua W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bays, John Timothy [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Qu, Jun [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); West, Brian [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2016-09-30

The manuscript captures the chronological succession of the molecular design progression through multiple architectures and topologies of the polymeric viscosity index improvers and their rheology bench test performance. Tribology testing was also performed on selected analogs and their friction and wear was evaluated. Finally, a top performing polymer was selected for engine testing, scaled-up, and its rheological performance in a complete formulation was assessed. The engine performance of the viscosity index improver was examined against an industry-established baseline.

Classical orbits in power-law potentials

International Nuclear Information System (INIS)

Grant, A.K.; Rosner, J.L.

1994-01-01

The motion of bodies in power-law potentials of the form V(r)=λr α has been of interest ever since the time of Newton and Hooke. Aspects of the relation between powers α and bar α, where (α+2)(bar α+2)=4, are derived for classical motion and the relation to the quantum-mechanical problem is given. An improvement on a previous expression for the WKB quantization condition for nonzero orbital angular momenta is obtained. Relations with previous treatments, such as those of Newton, Bertrand, Bohlin, Faure, and Arnold, are noted, and a brief survey of the literature on the problem over more than three centuries is given

Determining Rheological Parameters of Generalized Yield-Power-Law Fluid Model

Directory of Open Access Journals (Sweden)

Stryczek Stanislaw

2004-09-01

Full Text Available The principles of determining rheological parameters of drilling muds described by a generalized yield-power-law are presented in the paper. Functions between tangent stresses and shear rate are given. The conditions of laboratory measurements of rheological parameters of generalized yield-power-law fluids are described and necessary mathematical relations for rheological model parameters given. With the block diagrams, the methodics of numerical solution of these relations has been presented. Rheological parameters of an exemplary drilling mud have been calculated with the use of this numerical program.

Electrohydrodynamic stability of two stratified power law liquid in couette flow

International Nuclear Information System (INIS)

Eldabe, N.T.

1988-01-01

Consideration is given to the stability of the flow of two power law liquids under the influence of normal electric field between two infinite parallel planes when one of the planes moves with constant velocity in its own plane. It is found that the electric fields have a dramatic effect and can be chosen to stabilize or destabilize the flow. The effects of the power law parameters on the problem are examinated

Power-law versus exponential relaxation of {sup 29}Si nucleus spins in Si:B crystals

Energy Technology Data Exchange (ETDEWEB)

Koplak, O.V. [Institute of Problems of Chemical Physics, 142432 Chernogolovka, Moscow (Russian Federation); Taras Shevchenko Kiev National University and National Academy of Sciences, 01033 Kiev (Ukraine); Talantsev, A.D., E-mail: adt@icp.ac.ru [Institute of Problems of Chemical Physics, 142432 Chernogolovka, Moscow (Russian Federation); Morgunov, R.B. [Institute of Problems of Chemical Physics, 142432 Chernogolovka, Moscow (Russian Federation); Sholokhov Moscow State University for the Humanities, 109240 Moscow (Russian Federation)

2016-02-15

The Si:B micro-crystals enriched with {sup 29}Si isotope have been studied by high resolution nuclear magnetic resonance (NMR) in the 300–800 K temperature range. The recovery of nuclear magnetization saturated by radiofrequency impulses follows pure power-law kinetics at 300 K, while admixture of exponential relaxation takes place at 500 K. The power-law relaxation corresponds to direct electron–nuclear relaxation due to the inhomogeneous distribution of paramagnetic centers, while exponential kinetics corresponds to the nuclear spin diffusion mechanism. The inhomogeneous distribution of deformation defects is a most probable reason of the power-law kinetics of nuclear spin relaxation. - Highlights: • {sup 29}Si nuclear magnetization relaxation follows mixed power-exponential law. • Power-law corresponds to direct electron–nuclear relaxation. • Admixture of exponential relaxation corresponds to the nuclear spin diffusion. • Inhomogeneously distributed deformation defects are responsible for power low. • Homogeneously distributed Boron acceptors are responsible for exponential part.

Poissonian renormalizations, exponentials, and power laws

Science.gov (United States)

Eliazar, Iddo

2013-05-01

This paper presents a comprehensive “renormalization study” of Poisson processes governed by exponential and power-law intensities. These Poisson processes are of fundamental importance, as they constitute the very bedrock of the universal extreme-value laws of Gumbel, Fréchet, and Weibull. Applying the method of Poissonian renormalization we analyze the emergence of these Poisson processes, unveil their intrinsic dynamical structures, determine their domains of attraction, and characterize their structural phase transitions. These structural phase transitions are shown to be governed by uniform and harmonic intensities, to have universal domains of attraction, to uniquely display intrinsic invariance, and to be intimately connected to “white noise” and to “1/f noise.” Thus, we establish a Poissonian explanation to the omnipresence of white and 1/f noises.

Digital viscosity controller for fossil power plants; Controlador digital de viscosidad para plantas termoelectricas

Energy Technology Data Exchange (ETDEWEB)

Bautista B, Amberto; Ocampo P, Carlos; Gutierrez A, Ruben; Madinaveitia V, Miguel [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

1990-12-31

Upon the need of increasing the efficiency of the existing fossil power plants in Mexico, the Instrumentation and Control Department of the Instituto de Investigaciones Electricas (IIE) designed and built a viscosity controller to enhance the fuel oil heating process. The system strategy, that allows the control either by temperature or viscosity considers, as an important element, the changing characteristics of the supplied fuels. The equipment that is utilized forms apart of the line Acquisition and Control System (ACS) developed at the same Institute, that has been successfully applied in other systems. [Espanol] Ante la necesidad de aumentar la eficiencia de las plantas termoelectricas existentes en Mexico, el Departamento de Instrumentacion y Control, del Instituto de Investigaciones Electricas (IIE), diseno y construyo un controlador de viscosidad para mejorar el proceso de calentamiento del aceite combustible. La estrategia del sistema, que permite controlar ya sea por viscosidad o por temperatura, considera como elemento importante las caracteristicas cambiantes de los combustibles suministrados. El equipo que se utiliza forma parte de la linea SAC (sistema de adquisicion y control), desarrollada en el mismo Instituto, que se ha aplicado satisfactoriamente en otros sistemas.

Digital viscosity controller for fossil power plants; Controlador digital de viscosidad para plantas termoelectricas

Energy Technology Data Exchange (ETDEWEB)

Bautista B, Amberto; Ocampo P, Carlos; Gutierrez A, Ruben; Madinaveitia V, Miguel [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

1989-12-31

Upon the need of increasing the efficiency of the existing fossil power plants in Mexico, the Instrumentation and Control Department of the Instituto de Investigaciones Electricas (IIE) designed and built a viscosity controller to enhance the fuel oil heating process. The system strategy, that allows the control either by temperature or viscosity considers, as an important element, the changing characteristics of the supplied fuels. The equipment that is utilized forms apart of the line Acquisition and Control System (ACS) developed at the same Institute, that has been successfully applied in other systems. [Espanol] Ante la necesidad de aumentar la eficiencia de las plantas termoelectricas existentes en Mexico, el Departamento de Instrumentacion y Control, del Instituto de Investigaciones Electricas (IIE), diseno y construyo un controlador de viscosidad para mejorar el proceso de calentamiento del aceite combustible. La estrategia del sistema, que permite controlar ya sea por viscosidad o por temperatura, considera como elemento importante las caracteristicas cambiantes de los combustibles suministrados. El equipo que se utiliza forma parte de la linea SAC (sistema de adquisicion y control), desarrollada en el mismo Instituto, que se ha aplicado satisfactoriamente en otros sistemas.

Relation of the second law of thermodynamics to the power conversion of energy fluctuations

International Nuclear Information System (INIS)

Yater, J.C.

1979-01-01

The relation of the second law of thermodynamics to the power conversion of fluctuation energy is analyzed using the master equation of the model for the conversion circuit. The performance equation for independent particles shows that the power-conversion performance is given by the second law both for classical and quantum-effect diodes. The relation of the second law to power-conversion models based on the theoretical and experimental results for diode performance for interacting particles exhibiting many-body, multiparticle, or other anomalous and excess-current effects is examined. The performance equations are derived from the master equation for models for interacting particles to determine the conditions required by the second law for power conversion. These conditions are given in terms of the distribution throughout the power-conversion circuit for all the parameters that determine the particle and multiparticle barrier-crossing probability such as the effective mass and spectral density functions. Circuits for spectroscopic measurements for power-conversion circuits with interacting particles are noted. Using selected experimental values for the diode nonlinearity factors in these circuits, open circuit voltages are computed that are not predicted by the second law of thermodynamics

A molecular dynamics examination of the relationship between self-diffusion and viscosity in liquid metals

Science.gov (United States)

Lü, Yongjun; Cheng, Hao; Chen, Min

2012-06-01

The self-diffusion coefficients D and the viscosities η of elemental Ni, Cu, and Ni-Si alloys have been calculated over a wide temperature range by molecular dynamics simulations. For elemental Ni and Cu, Arrhenius-law variations of D and η with temperature dominate. The temperature dependence of Dη can be approximated by a linear relation, whereas the Stokes-Einstein relation is violated. The calculations of D and η are extended to the regions close to the crystallization of Ni95Si5, Ni90Si10, and the glass transitions of Ni80Si20 and Ni75Si25. The results show that both D and η strongly deviate from the Arrhenius law in the vicinity of phase transitions, exhibiting a power-law divergence. We find a decoupling of diffusion and viscous flow just above the crystallization of Ni95Si5 and Ni90Si10. For the two glass-forming alloys, Ni80Si20 and Ni75Si25, the relation Dη = const is obeyed as the glass transition is approached, indicating a dynamic coupling as predicted by the mode-coupling theory. This coupling is enhanced with increasing Si composition and at 25%, Si spans a wide temperature range through the melting point. The decoupling is found to be related to the distribution of local ordered structure in the melts. The power-law governing the growth of solid-like clusters prior to crystallization creates a dynamic heterogeneity responsible for decoupling.

Dynamics of a map with a power-law tail

International Nuclear Information System (INIS)

Botella-Soler, V; Ros, J; Oteo, J A

2009-01-01

We analyze a one-dimensional piecewise continuous discrete model proposed originally in studies on population ecology. The map is composed of a linear part and a power-law decreasing piece, and has three parameters. The system presents both regular and chaotic behavior. We study numerically and, in part, analytically different bifurcation structures. Particularly interesting is the description of the abrupt order-to-chaos transition mediated by an attractor made of an infinite number of limit cycles with only a finite number of different periods. It is shown that the power-law piece in the map is at the origin of this type of bifurcation. The system exhibits interior crises and crisis-induced intermittency.

Characterizing and predicting the robustness of power-law networks

International Nuclear Information System (INIS)

LaRocca, Sarah; Guikema, Seth D.

2015-01-01

Power-law networks such as the Internet, terrorist cells, species relationships, and cellular metabolic interactions are susceptible to node failures, yet maintaining network connectivity is essential for network functionality. Disconnection of the network leads to fragmentation and, in some cases, collapse of the underlying system. However, the influences of the topology of networks on their ability to withstand node failures are poorly understood. Based on a study of the response of 2000 randomly-generated power-law networks to node failures, we find that networks with higher nodal degree and clustering coefficient, lower betweenness centrality, and lower variability in path length and clustering coefficient maintain their cohesion better during such events. We also find that network robustness, i.e., the ability to withstand node failures, can be accurately predicted a priori for power-law networks across many fields. These results provide a basis for designing new, more robust networks, improving the robustness of existing networks such as the Internet and cellular metabolic pathways, and efficiently degrading networks such as terrorist cells. - Highlights: • Examine relationship between network topology and robustness to failures. • Relationship is statistically significant for scale-free networks. • Use statistical models to estimate robustness to failures for real-world networks

Phase diagram of power law and Lennard-Jones systems: Crystal phases

International Nuclear Information System (INIS)

Travesset, Alex

2014-01-01

An extensive characterization of the low temperature phase diagram of particles interacting with power law or Lennard-Jones potentials is provided from Lattice Dynamical Theory. For power law systems, only two lattice structures are stable for certain values of the exponent (or softness) (A15, body centered cube (bcc)) and two more (face centered cubic (fcc), hexagonal close packed (hcp)) are always stable. Among them, only the fcc and bcc are equilibrium states. For Lennard-Jones systems, the equilibrium states are either hcp or fcc, with a coexistence curve in pressure and temperature that shows reentrant behavior. The hcp solid never coexists with the liquid. In all cases analyzed, for both power law and Lennard-Jones potentials, the fcc crystal has higher entropy than the hcp. The role of anharmonic terms is thoroughly analyzed and a general thermodynamic integration to account for them is proposed

The power of law : Spinoza’s contribution to legal theory

NARCIS (Netherlands)

Gribnau, J.L.M.

1995-01-01

Spinoza’s legal theoretical ideas are based on psychological and sociological regularities in human behaviour of knowledge. His naturalistic and descriptive approach of the relationship between law and power shows that the exercise of state power on that basis - within the constitutional constraints

A comparison of performance of several artificial intelligence methods for predicting the dynamic viscosity of TiO2/SAE 50 nano-lubricant

Science.gov (United States)

Hemmat Esfe, Mohammad; Tatar, Afshin; Ahangar, Mohammad Reza Hassani; Rostamian, Hossein

2018-02-01

Since the conventional thermal fluids such as water, oil, and ethylene glycol have poor thermal properties, the tiny solid particles are added to these fluids to increase their heat transfer improvement. As viscosity determines the rheological behavior of a fluid, studying the parameters affecting the viscosity is crucial. Since the experimental measurement of viscosity is expensive and time consuming, predicting this parameter is the apt method. In this work, three artificial intelligence methods containing Genetic Algorithm-Radial Basis Function Neural Networks (GA-RBF), Least Square Support Vector Machine (LS-SVM) and Gene Expression Programming (GEP) were applied to predict the viscosity of TiO2/SAE 50 nano-lubricant with Non-Newtonian power-law behavior using experimental data. The correlation factor (R2), Average Absolute Relative Deviation (AARD), Root Mean Square Error (RMSE), and Margin of Deviation were employed to investigate the accuracy of the proposed models. RMSE values of 0.58, 1.28, and 6.59 and R2 values of 0.99998, 0.99991, and 0.99777 reveal the accuracy of the proposed models for respective GA-RBF, CSA-LSSVM, and GEP methods. Among the developed models, the GA-RBF shows the best accuracy.

Power Laws, Scale-Free Networks and Genome Biology

CERN Document Server

Koonin, Eugene V; Karev, Georgy P

2006-01-01

Power Laws, Scale-free Networks and Genome Biology deals with crucial aspects of the theoretical foundations of systems biology, namely power law distributions and scale-free networks which have emerged as the hallmarks of biological organization in the post-genomic era. The chapters in the book not only describe the interesting mathematical properties of biological networks but moves beyond phenomenology, toward models of evolution capable of explaining the emergence of these features. The collection of chapters, contributed by both physicists and biologists, strives to address the problems in this field in a rigorous but not excessively mathematical manner and to represent different viewpoints, which is crucial in this emerging discipline. Each chapter includes, in addition to technical descriptions of properties of biological networks and evolutionary models, a more general and accessible introduction to the respective problems. Most chapters emphasize the potential of theoretical systems biology for disco...

Solution for laminar natural convection flows in a square cavity with temperature dependent viscosity

Energy Technology Data Exchange (ETDEWEB)

Sanchez, J.G. [Parsons Brinckerhoff, New York, NY (United States)

1995-12-31

This paper presents an examination of numerical results for the buoyancy-driven convection heat transfer problem, in a two-dimensional enclosure under steady-state, laminar, incompressible, and temperature dependent viscosity fluid flow conditions. The vertical walls are exposed to different temperatures and the top and bottom are insulated. Rayleigh numbers of 10{sup 4}, 10{sup 5}, and 10{sup 6} are considered. Specific heat, thermal conductivity, and the thermal expansion coefficient are assumed constant. Density variation is included using the Oberbeck-Boussinesq approximation. The results are obtained using the SIMPLEC solution technique based on a power-law, finite-volume discretization scheme. The hydrodynamic and thermal fields are presented at various locations in the enclosures.

Phenomenological and statistical analyses of turbulence in forced convection with temperature-dependent viscosity under non-Boussinesq condition.

Science.gov (United States)

Yahya, S M; Anwer, S F; Sanghi, S

2013-10-01

In this work, Thermal Large Eddy Simulation (TLES) is performed to study the behavior of weakly compressible Newtonian fluids with anisotropic temperature-dependent viscosity in forced convection turbulent flow. A systematic analysis of variable-viscosity effects, isolated from gravity, with relevance to industrial cooling/heating applications is being carried out. A LES of a planar channel flow with significant heat transfer at a low Mach number was performed to study effects of fluid property variation on the near-wall turbulence structure. In this flow configuration the top wall is maintained at a higher temperature (T hot ) than the bottom wall (T cold ). The temperature ratio (R θ = T hot /T cold ) is fixed at 1.01, 2 and 3 to study the effects of property variations at low Mach number. Results indicate that average and turbulent fields undergo significant changes. Compared with isothermal flow with constant viscosity, we observe that turbulence is enhanced in the cold side of the channel, characterized by locally lower viscosity whereas a decrease of turbulent kinetic energy is found at the hot wall. The turbulent structures near the cold wall are very short and densely populated vortices but near the hot wall there seems to be a long streaky structure or large elongated vortices. Spectral study reveals that turbulence is completely suppressed at the hot side of the channel at a large temperature ratio because no inertial zone is obtained (i.e. index of Kolmogorov scaling law is zero) from the spectra in these region.

Judicial law-making: Unlocking the creative powers of judges in ...

African Journals Online (AJOL)

... the creative powers of judges in terms of Section 39(2) of the constitution. ... that judges do indeed have a law-making function in the process of interpretation. ... The article examines the extent to which the judiciary can use this power in a ...

Statistical interpretation of transient current power-law decay in colloidal quantum dot arrays

Energy Technology Data Exchange (ETDEWEB)

Sibatov, R T, E-mail: ren_sib@bk.ru [Ulyanovsk State University, 432000, 42 Leo Tolstoy Street, Ulyanovsk (Russian Federation)

2011-08-01

A new statistical model of the charge transport in colloidal quantum dot arrays is proposed. It takes into account Coulomb blockade forbidding multiple occupancy of nanocrystals and the influence of energetic disorder of interdot space. The model explains power-law current transients and the presence of the memory effect. The fractional differential analogue of the Ohm law is found phenomenologically for nanocrystal arrays. The model combines ideas that were considered as conflicting by other authors: the Scher-Montroll idea about the power-law distribution of waiting times in localized states for disordered semiconductors is applied taking into account Coulomb blockade; Novikov's condition about the asymptotic power-law distribution of time intervals between successful current pulses in conduction channels is fulfilled; and the carrier injection blocking predicted by Ginger and Greenham (2000 J. Appl. Phys. 87 1361) takes place.

Statistical interpretation of transient current power-law decay in colloidal quantum dot arrays

International Nuclear Information System (INIS)

Sibatov, R T

2011-01-01

A new statistical model of the charge transport in colloidal quantum dot arrays is proposed. It takes into account Coulomb blockade forbidding multiple occupancy of nanocrystals and the influence of energetic disorder of interdot space. The model explains power-law current transients and the presence of the memory effect. The fractional differential analogue of the Ohm law is found phenomenologically for nanocrystal arrays. The model combines ideas that were considered as conflicting by other authors: the Scher-Montroll idea about the power-law distribution of waiting times in localized states for disordered semiconductors is applied taking into account Coulomb blockade; Novikov's condition about the asymptotic power-law distribution of time intervals between successful current pulses in conduction channels is fulfilled; and the carrier injection blocking predicted by Ginger and Greenham (2000 J. Appl. Phys. 87 1361) takes place.

Indian English Evolution and Focusing Visible Through Power Laws

Directory of Open Access Journals (Sweden)

Vineeta Chand

2017-11-01

Full Text Available New dialect emergence and focusing in language contact settings is difficult to capture and date in terms of global structural dialect stabilization. This paper explores whether diachronic power law frequency distributions can provide evidence of dialect evolution and new dialect focusing, by considering the quantitative frequency characteristics of three diachronic Indian English (IE corpora (1970s–2008. The results demonstrate that IE consistently follows power law frequency distributions and the corpora are each best fit by Mandelbrot’s Law. Diachronic changes in the constants are interpreted as evidence of lexical and syntactic collocational focusing within the process of new dialect formation. Evidence of new dialect focusing is also visible through apparent time comparison of spoken and written data. Age and gender-separated sub-corpora of the most recent corpus show minimal deviation, providing apparent time evidence for emerging IE dialect stability. From these findings, we extend the interpretation of diachronic changes in the β coefficient—as indicative of changes in the degree of synthetic/analytic structure—so that β is also sensitive to grammaticalization and changes in collocational patterns.

Blinking in quantum dots: The origin of the grey state and power law statistics

Science.gov (United States)

Ye, Mao; Searson, Peter C.

2011-09-01

Quantum dot (QD) blinking is characterized by switching between an “on” state and an “off” state, and a power-law distribution of on and off times with exponents from 1.0 to 2.0. The origin of blinking behavior in QDs, however, has remained a mystery. Here we describe an energy-band model for QDs that captures the full range of blinking behavior reported in the literature and provides new insight into features such as the gray state, the power-law distribution of on and off times, and the power-law exponents.

The speed-curvature power law in Drosophila larval locomotion.

Science.gov (United States)

Zago, Myrka; Lacquaniti, Francesco; Gomez-Marin, Alex

2016-10-01

We report the discovery that the locomotor trajectories of Drosophila larvae follow the power-law relationship between speed and curvature previously found in the movements of human and non-human primates. Using high-resolution behavioural tracking in controlled but naturalistic sensory environments, we tested the law in maggots tracing different trajectory types, from reaching-like movements to scribbles. For most but not all flies, we found that the law holds robustly, with an exponent close to three-quarters rather than to the usual two-thirds found in almost all human situations, suggesting dynamic effects adding on purely kinematic constraints. There are different hypotheses for the origin of the law in primates, one invoking cortical computations, another viscoelastic muscle properties coupled with central pattern generators. Our findings are consistent with the latter view and demonstrate that the law is possible in animals with nervous systems orders of magnitude simpler than in primates. Scaling laws might exist because natural selection favours processes that remain behaviourally efficient across a wide range of neural and body architectures in distantly related species. © 2016 The Authors.

Density, refractive index, interfacial tension, and viscosity of ionic liquids [EMIM][EtSO4], [EMIM][NTf2], [EMIM][N(CN)2], and [OMA][NTf2] in dependence on temperature at atmospheric pressure.

Science.gov (United States)

Fröba, Andreas P; Kremer, Heiko; Leipertz, Alfred

2008-10-02

The density, refractive index, interfacial tension, and viscosity of ionic liquids (ILs) [EMIM][EtSO 4] (1-ethyl-3-methylimidazolium ethylsulfate), [EMIM][NTf 2] (1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide), [EMIM][N(CN) 2] (1-ethyl-3-methylimidazolium dicyanimide), and [OMA][NTf 2] (trioctylmethylammonium bis(trifluoromethylsulfonyl)imide) were studied in dependence on temperature at atmospheric pressure both by conventional techniques and by surface light scattering (SLS). A vibrating tube densimeter was used for the measurement of density at temperatures from (273.15 to 363.15) K and the results have an expanded uncertainty ( k = 2) of +/-0.02%. Using an Abbe refractometer, the refractive index was measured for temperatures between (283.15 and 313.15) K with an expanded uncertainty ( k = 2) of about +/-0.0005. The interfacial tension was obtained from the pendant drop technique at a temperature of 293.15 K with an expanded uncertainty ( k = 2) of +/-1%. For higher and lower temperatures, the interfacial tension was estimated by an adequate prediction scheme based on the datum at 293.15 K and the temperature dependence of density. For the ILs studied within this work, at a first order approximation, the quantity directly accessible by the SLS technique was the ratio of surface tension to dynamic viscosity. By combining the experimental results of the SLS technique with density and interfacial tension from conventional techniques, the dynamic viscosity could be obtained for temperatures between (273.15 and 333.15) K with an estimated expanded uncertainty ( k = 2) of less than +/-3%. The measured density, refractive index, and viscosity are represented by interpolating expressions with differences between the experimental and calculated values that are comparable with but always smaller than the expanded uncertainties ( k = 2). Besides a comparison with the literature, the influence of structural variations on the thermophysical properties of the

Power-law Decay and the Ergodic-Nonergodic Transition in Simple Fluids

OpenAIRE

Spyridis, Paul; Mazenko, Gene F.

2013-01-01

It is well known that mode coupling theory (MCT) leads to a two step power-law time decay in dense simple fluids. We show that much of the mathematical machinery used in the MCT analysis can be taken over to the analysis of the systematic theory developed in the Fundamental Theory of Statistical Particle Dynamics (arXiv:0905.4904). We show how the power-law exponents can be computed in the second-order approximation where we treat hard-sphere fluids with statics described by the Percus-Yevick...

Refractive index and solubility control of para-cymene solutions for index-matched fluid-structure interaction studies

Science.gov (United States)

Fort, Charles; Fu, Christopher D.; Weichselbaum, Noah A.; Bardet, Philippe M.

2015-12-01

To deploy optical diagnostics such as particle image velocimetry or planar laser-induced fluorescence (PLIF) in complex geometries, it is beneficial to use index-matched facilities. A binary mixture of para-cymene and cinnamaldehyde provides a viable option for matching the refractive index of acrylic, a common material for scaled models and test sections. This fluid is particularly appropriate for large-scale facilities and when a low-density and low-viscosity fluid is sought, such as in fluid-structure interaction studies. This binary solution has relatively low kinematic viscosity and density; its use enables the experimentalist to select operating temperature and to increase fluorescence signal in PLIF experiments. Measurements of spectral and temperature dependence of refractive index, density, and kinematic viscosity are reported. The effect of the binary mixture on solubility control of Rhodamine 6G is also characterized.

Problems of cartel law in license contracts within the power economy

International Nuclear Information System (INIS)

Hueffer, U.

1992-01-01

First the licence contract is presented as a particularly important instrument of the power economy. In a second step a link is established with cartel law; that is, the special status of the power economy under cartel law and the significance of the licence contract within this context are illuminated. On this basis then, a very controversial complex of problems is entered into: the assessment of so-called expiration clauses in licence contracts, i.e. the legal situation upon expiration of a licence contract. It turns out that qualms about the time value being the takeover price have no legal basis. The fact that they were expressed at all is due to the lack of a synopsis of the relevant subareas of commercial law. Scientific purposes require a synopsis of the commercial law concerned rather than an argument in which each party splits off single aspects of the issue. (orig./HSCH) [de

Preinflationary dynamics in loop quantum cosmology: Power-law potentials

Science.gov (United States)

Shahalam, M.; Sharma, Manabendra; Wu, Qiang; Wang, Anzhong

2017-12-01

In this paper, we study the preinflationary dynamics for the power-law potential [V (ϕ )∝ϕn] with n consideration and compare our results with the ones obtained previously for different potentials.

Energy law. The legal boundary conditions of power supply. 2. rev. ed.

International Nuclear Information System (INIS)

Stuhlmacher, Gerd; Stappert, Holger; Jansen, Guido

2015-01-01

Now appearing in its second edition, this book presents a comprehensive overview of the legal framework governing the energy sector. It provides readily understandable coverage, across the relevant subfields of law, of the legal regulations applicable to any manner of activity in the energy sector along with a wealth of practical advice on the interpretation and application of legal provisions. The content has been thoroughly revised, updated to reflect the current status of legislation and supplemented with numerous chapters. The 2014 amendment of the Renewable Energy Law (EEG) and its practical impact have also been taken into account. The following topics are covered amongst others: unbundling of network operation; connection and access to networks and metering; network charges and incentive regulation; easement contracts; energy supply and basic services; energy and electricity taxes; cartel law, law on operating aids, procurement law; energy trade OTC and at exchanges; energy trade surveillance law; fuel production and fracking; conventional and nuclear power production; renewable energy production (including offshore production); energy storage and power-to-gas; transmission line construction; climate protection (including the 2014 EEG, emission trade and the Law on the Promotion of Renewable Energy in the Heat Sector); cogeneration law, district heating and contracting; and investment protection.

A Dual Power Law Distribution for the Stellar Initial Mass Function

Science.gov (United States)

Hoffmann, Karl Heinz; Essex, Christopher; Basu, Shantanu; Prehl, Janett

2018-05-01

We introduce a new dual power law (DPL) probability distribution function for the mass distribution of stellar and substellar objects at birth, otherwise known as the initial mass function (IMF). The model contains both deterministic and stochastic elements, and provides a unified framework within which to view the formation of brown dwarfs and stars resulting from an accretion process that starts from extremely low mass seeds. It does not depend upon a top down scenario of collapsing (Jeans) masses or an initial lognormal or otherwise IMF-like distribution of seed masses. Like the modified lognormal power law (MLP) distribution, the DPL distribution has a power law at the high mass end, as a result of exponential growth of mass coupled with equally likely stopping of accretion at any time interval. Unlike the MLP, a power law decay also appears at the low mass end of the IMF. This feature is closely connected to the accretion stopping probability rising from an initially low value up to a high value. This might be associated with physical effects of ejections sometimes (i.e., rarely) stopping accretion at early times followed by outflow driven accretion stopping at later times, with the transition happening at a critical time (therefore mass). Comparing the DPL to empirical data, the critical mass is close to the substellar mass limit, suggesting that the onset of nuclear fusion plays an important role in the subsequent accretion history of a young stellar object.

Revision of by-laws about effluents of EdF's nuclear power plants

International Nuclear Information System (INIS)

2002-01-01

In France, in application of the clean water law from January 3, 1992 and since the decree 95-540 from May 4, 1995, each basic nuclear facility receives a single permission which covers both its water takes and its radioactive and non-radioactive effluents. This decree, initially dedicated to new facilities has been enlarged to all existing installations for which the prefectorial by-laws have reached their date-line. Thus, up to now, five inter-ministerial by-laws have renewed the permissions of water takes and effluents evacuation of the power plants of Saint-Laurent-des-Eaux (Loir-et-Cher), Flamanville (Manche), Paluel (Seine-Maritime), Belleville (Cher) and Saint-Alban (Isere). These by-laws foresee an important abatement of the effluents and concern more particularly the tritium, 14 C, the iodine isotopes and also some other non-radioactive chemical compounds. This document is a compilation of all revised by-laws about effluents and concerning the nuclear power plants listed above. (J.S.)

[Index of Nutritional Purchasing Power Parity: comparison of caloric costs of a healthy versus an unhealthy diet].

Science.gov (United States)

Mendoza Velázquez, Alfonso

2012-01-01

Develop the Index of Nutritional Purchasing Power Parity (Nut3-CiO) as an instrument to compare the caloric costs of a healthy versus an unhealthy diet between regions or cities in a country over time. Indices of caloric prices were constructed and the "law of one price" was used to derive the Nut3-CiO index. Caloric inflation rates were obtained using basic descriptive statistics. The Nut3-CiO was applied in the major cities of Mexico during the period from January 1996 to December 2010. The statistical behavior of the Nut3-CiO revealed that, in Mexican cities, products for a typical diet are less expensive than products for a healthy diet. The findings showed a cyclical behavior to the index, a high correlation between inflation for the typical diet and inflation for the market basket, and a high persistence of prices. The Nut3-CiO index makes it possible to periodically compare the price differential of two types of diets-typical and healthy-between cities in a single country. This instrument could help health authorities identify the cities where it is easier or more difficult for consumers to access a typical or healthy diet in terms of cost. Furthermore, it makes it possible to estimate the percentage adjustment necessary in each city to attain levels of nutritional purchasing power parity.

Using Power-Law Degree Distribution to Accelerate PageRank

Directory of Open Access Journals (Sweden)

Zhaoyan Jin

2012-12-01

Full Text Available The PageRank vector of a network is very important, for it can reflect the importance of a Web page in the World Wide Web, or of a people in a social network. However, with the growth of the World Wide Web and social networks, it needs more and more time to compute the PageRank vector of a network. In many real-world applications, the degree and PageRank distributions of these complex networks conform to the Power-Law distribution. This paper utilizes the degree distribution of a network to initialize its PageRank vector, and presents a Power-Law degree distribution accelerating algorithm of PageRank computation. Experiments on four real-world datasets show that the proposed algorithm converges more quickly than the original PageRank algorithm.

Phase space analysis for anisotropic universe with nonlinear bulk viscosity

Science.gov (United States)

Sharif, M.; Mumtaz, Saadia

2018-06-01

In this paper, we discuss phase space analysis of locally rotationally symmetric Bianchi type I universe model by taking a noninteracting mixture of dust like and viscous radiation like fluid whose viscous pressure satisfies a nonlinear version of the Israel-Stewart transport equation. An autonomous system of equations is established by defining normalized dimensionless variables. In order to investigate stability of the system, we evaluate corresponding critical points for different values of the parameters. We also compute power-law scale factor whose behavior indicates different phases of the universe model. It is found that our analysis does not provide a complete immune from fine-tuning because the exponentially expanding solution occurs only for a particular range of parameters. We conclude that stable solutions exist in the presence of nonlinear model for bulk viscosity with different choices of the constant parameter m for anisotropic universe.

Spreading law of non-Newtonian power-law liquids on a spherical substrate by an energy-balance approach.

Science.gov (United States)

Iwamatsu, Masao

2017-07-01

The spreading of a cap-shaped spherical droplet of non-Newtonian power-law liquids, both shear-thickening and shear-thinning liquids, that completely wet a spherical substrate is theoretically investigated in the capillary-controlled spreading regime. The crater-shaped droplet model with the wedge-shaped meniscus near the three-phase contact line is used to calculate the viscous dissipation near the contact line. Then the energy balance approach is adopted to derive the equation that governs the evolution of the contact line. The time evolution of the dynamic contact angle θ of a droplet obeys a power law θ∼t^{-α} with the spreading exponent α, which is different from Tanner's law for Newtonian liquids and those for non-Newtonian liquids on a flat substrate. Furthermore, the line-tension dominated spreading, which could be realized on a spherical substrate for late-stage of spreading when the contact angle becomes low and the curvature of the contact line becomes large, is also investigated.

Geomorphological and hydrological implications of a given hydraulic geometry relationship, beyond the power-law

Science.gov (United States)

Kim, JongChun; Paik, Kyungrock

2015-04-01

Channel geometry and hydraulic characteristics of a given river network, i.e., spatio-temporal variability of width, depth, and velocity, can be described as power functional relationships of flow discharge, named 'hydraulic geometry' (Leopold and Maddock, 1953). Many studies have focused on the implication of this power-law itself, i.e., self-similarity, and accordingly its exponents. Coefficients of the power functional relationships, on the contrary, have received little attention. They are often regarded as empirical constants, determined by 'best fitting' to the power-law without significant scientific implications. Here, we investigate and claim that power-law coefficients of hydraulic geometry relationships carry vital information of a given river system. We approach the given problem on the basis of 'basin hydraulic geometry' formulation (Stall and Fok, 1968) which decomposes power-law coefficients into more elementary constants. The linkage between classical power-law relationship (Leopold and Maddock, 1953) and the basin hydraulic geometry is provided by Paik and Kumar (2004). On the basis of this earlier study, it can be shown that coefficients and exponents of power-law hydraulic geometry are interrelated. In this sense, we argue that more elementary constants that constitute both exponents and coefficients carry important messages. In this presentation, we will demonstrate how these elementary constants vary over a wide range of catchments provided from Stall and Fok (1968) and Stall and Yang (1970). Findings of this study can provide new insights on fundamental understanding about hydraulic geometry relationships. Further, we expect that this understanding can help interpretation of hydraulic geometry relationship in the context of flood propagation through a river system as well. Keywords: Hydraulic geometry; Power-law; River network References Leopold, L. B., & Maddock, T. J. (1953). The hydraulic geometry of stream channels and some physiographic

A recommended procedure for estimating the cosmic-ray spectral parameter of a simple power law

CERN Document Server

Howell, L W

2002-01-01

A simple power law model with single spectral index alpha sub 1 is believed to be an adequate description of the galactic cosmic-ray (GCR) proton flux at energies below 10 sup 1 sup 3 eV. Two procedures for estimating alpha sub 1 --the method of moments and maximum likelihood (ML)--are developed and their statistical performance are compared. The ML procedure is shown to be the superior approach and is then generalized for application to real cosmic-ray data sets. Several other important results, such as the relationship between collecting power and detector energy resolution and inclusion of a non-Gaussian detector response function, are presented. These results have many practical benefits in the design phase of a cosmic-ray detector as they permit instrument developers to make important trade studies in design parameters as a function of one of the science objectives.

Hydrodynamics-based functional forms of activity metabolism: a case for the power-law polynomial function in animal swimming energetics.

Science.gov (United States)

Papadopoulos, Anthony

2009-01-01

The first-degree power-law polynomial function is frequently used to describe activity metabolism for steady swimming animals. This function has been used in hydrodynamics-based metabolic studies to evaluate important parameters of energetic costs, such as the standard metabolic rate and the drag power indices. In theory, however, the power-law polynomial function of any degree greater than one can be used to describe activity metabolism for steady swimming animals. In fact, activity metabolism has been described by the conventional exponential function and the cubic polynomial function, although only the power-law polynomial function models drag power since it conforms to hydrodynamic laws. Consequently, the first-degree power-law polynomial function yields incorrect parameter values of energetic costs if activity metabolism is governed by the power-law polynomial function of any degree greater than one. This issue is important in bioenergetics because correct comparisons of energetic costs among different steady swimming animals cannot be made unless the degree of the power-law polynomial function derives from activity metabolism. In other words, a hydrodynamics-based functional form of activity metabolism is a power-law polynomial function of any degree greater than or equal to one. Therefore, the degree of the power-law polynomial function should be treated as a parameter, not as a constant. This new treatment not only conforms to hydrodynamic laws, but also ensures correct comparisons of energetic costs among different steady swimming animals. Furthermore, the exponential power-law function, which is a new hydrodynamics-based functional form of activity metabolism, is a special case of the power-law polynomial function. Hence, the link between the hydrodynamics of steady swimming and the exponential-based metabolic model is defined.

Hydrodynamics-based functional forms of activity metabolism: a case for the power-law polynomial function in animal swimming energetics.

Directory of Open Access Journals (Sweden)

Anthony Papadopoulos

Full Text Available The first-degree power-law polynomial function is frequently used to describe activity metabolism for steady swimming animals. This function has been used in hydrodynamics-based metabolic studies to evaluate important parameters of energetic costs, such as the standard metabolic rate and the drag power indices. In theory, however, the power-law polynomial function of any degree greater than one can be used to describe activity metabolism for steady swimming animals. In fact, activity metabolism has been described by the conventional exponential function and the cubic polynomial function, although only the power-law polynomial function models drag power since it conforms to hydrodynamic laws. Consequently, the first-degree power-law polynomial function yields incorrect parameter values of energetic costs if activity metabolism is governed by the power-law polynomial function of any degree greater than one. This issue is important in bioenergetics because correct comparisons of energetic costs among different steady swimming animals cannot be made unless the degree of the power-law polynomial function derives from activity metabolism. In other words, a hydrodynamics-based functional form of activity metabolism is a power-law polynomial function of any degree greater than or equal to one. Therefore, the degree of the power-law polynomial function should be treated as a parameter, not as a constant. This new treatment not only conforms to hydrodynamic laws, but also ensures correct comparisons of energetic costs among different steady swimming animals. Furthermore, the exponential power-law function, which is a new hydrodynamics-based functional form of activity metabolism, is a special case of the power-law polynomial function. Hence, the link between the hydrodynamics of steady swimming and the exponential-based metabolic model is defined.

Fractal approach towards power-law coherency to measure cross-correlations between time series

Czech Academy of Sciences Publication Activity Database

Krištoufek, Ladislav

2017-01-01

Roč. 50, č. 1 (2017), s. 193-200 ISSN 1007-5704 R&D Projects: GA ČR(CZ) GP14-11402P Institutional support: RVO:67985556 Keywords : power- law coherency * power- law cross-correlations * correlations Subject RIV: AH - Economics OBOR OECD: Applied Economics, Econometrics Impact factor: 2.784, year: 2016 http://library.utia.cas.cz/separaty/2017/E/kristoufek-0473066.pdf

Characterising rock fracture aperture-spacing relationships using power-law relationships: some considerations

Science.gov (United States)

Brook, Martin; Hebblewhite, Bruce; Mitra, Rudrajit

2016-04-01

The size-scaling of rock fractures is a well-studied problem in geology, especially for permeability quantification. The intensity of fractures may control the economic exploitation of fractured reservoirs because fracture intensity describes the abundance of fractures potentially available for fluid flow. Moreover, in geotechnical engineering, fractures are important for parameterisation of stress models and excavation design. As fracture data is often collected from widely-spaced boreholes where core recovery is often incomplete, accurate interpretation and representation of fracture aperture-frequency relationships from sparse datasets is important. Fracture intensity is the number of fractures encountered per unit length along a sample scanline oriented perpendicular to the fractures in a set. Cumulative frequency of fractures (F) is commonly related to fracture aperture (A) in the form of a power-law (F = aA-b), with variations in the size of the a coefficient between sites interpreted to equate to fracture frequency for a given aperture (A). However, a common flaw in this approach is that even a small change in b can have a large effect on the response of the fracture frequency (F) parameter. We compare fracture data from the Late Permian Rangal Coal Measures from Australia's Bowen Basin, with fracture data from Jurassic carbonates from the Sierra Madre Oriental, northeastern Mexico. Both power-law coefficient a and exponent b control the fracture aperture-frequency relationship in conjunction with each other; that is, power-laws with relatively low a coefficients have relatively high b exponents and vice versa. Hence, any comparison of different power-laws must take both a and b into consideration. The corollary is that different sedimentary beds in the Sierra Madre carbonates do not show ˜8× the fracture frequency for a given fracture aperture, as based solely on the comparison of coefficient a. Rather, power-law "sensitivity factors" developed from both

Anisotropic power-law inflation for a conformal-violating Maxwell model

Science.gov (United States)

Do, Tuan Q.; Kao, W. F.

2018-05-01

A set of power-law solutions of a conformal-violating Maxwell model with a non-standard scalar-vector coupling will be shown in this paper. In particular, we are interested in a coupling term of the form X^{2n} F^{μ ν }F_{μ ν } with X denoting the kinetic term of the scalar field. Stability analysis indicates that the new set of anisotropic power-law solutions is unstable during the inflationary phase. The result is consistent with the cosmic no-hair conjecture. We show, however, that a set of stable slowly expanding solutions does exist for a small range of parameters λ and n. Hence a small anisotropy can survive during the slowly expanding phase.

Power-law connections: From Zipf to Heaps and beyond

International Nuclear Information System (INIS)

Eliazar, Iddo I.; Cohen, Morrel H.

2013-01-01

In this paper we explore the asymptotic statistics of a general model of rank distributions in the large-ensemble limit; the construction of the general model is motivated by recent empirical studies of rank distributions. Applying Lorenzian, oligarchic, and Heapsian asymptotic analyses we establish a comprehensive set of closed-form results linking together rank distributions, probability distributions, oligarchy sizes, and innovation rates. In particular, the general results reveal the fundamental underlying connections between Zipf’s law, Pareto’s law, and Heaps’ law—three elemental empirical power-laws that are ubiquitously observed in the sciences. -- Highlights: ► The large-ensemble asymptotic statistics of rank distributions are explored. ► Lorenzian, oligarchic, and Heapsian asymptotic analyses are applied. ► Associated oligarchy sizes and induced innovation rates are analyzed. ► General elemental statistical connections are established. ► The underlying connections between Zipf’s, Pareto’s and Heaps’ laws are unveiled

Tachyon with an inverse power-law potential in a braneworld cosmology

Science.gov (United States)

Bilić, Neven; Domazet, Silvije; Djordjevic, Goran S.

2017-08-01

We study a tachyon cosmological model based on the dynamics of a 3-brane in the bulk of the second Randall-Sundrum model extended to more general warp functions. A well known prototype of such a generalization is the bulk with a selfinteracting scalar field. As a consequence of a generalized bulk geometry the cosmology on the observer brane is modified by the scale dependent four-dimensional gravitational constant. In particular, we study a power law warp factor which generates an inverse power-law potential V\\propto \\varphi-n of the tachyon field φ. We find a critical power n cr that divides two subclasses with distinct asymptotic behaviors: a dust universe for n>n_cr and a quasi de Sitter universe for 0.

Power law for the duration of recession and prosperity in Latin American countries

Science.gov (United States)

Redelico, Francisco O.; Proto, Araceli N.; Ausloos, Marcel

2008-11-01

Ormerod and Mounfield [P. Ormerod, C. Mounfield, Power law distribution of duration and magnitude of recessions in capitalist economies: Breakdown of scaling, Physica A 293 (2001) 573] and Ausloos et al. [M. Ausloos, J. Mikiewicz, M. Sanglier, The durations of recession and prosperity: Does their distribution follow a power or an exponential law? Physica A 339 (2004) 548] have independently analyzed the duration of recessions for developed countries through the evolution of the GDP in different time windows. It was found that there is a power law governing the duration distribution. We have analyzed data collected from 19 Latin American countries in order to observe whether such results are valid or not for developing countries. The case of prosperity years is also discussed. We observe that the power law of recession time intervals, see Ref. [1], is valid for Latin American countries as well. Thus an interesting point is discovered: the same scaling time is found in the case of recessions for the three data sets (ca. 1 year), and this could represent a universal feature. Other time scale parameters differ significantly from each other.

Power laws and elastic nonlinearity in materials with complex microstructure

Energy Technology Data Exchange (ETDEWEB)

Scalerandi, M., E-mail: marco.scalerandi@infm.polito.it

2016-01-28

Nonlinear ultrasonic methods have been widely used to characterize the microstructure of damaged solids and consolidated granular media. Besides distinguishing between materials exhibiting classical nonlinear behaviors from those exhibiting hysteresis, it could be of importance the discrimination between ultrasonic indications from different physical sources (scatterers). Elastic hysteresis could indeed be due to dislocations, grain boundaries, stick-slip at interfaces, etc. Analyzing data obtained on various concrete samples, we show that the power law behavior of the nonlinear indicator vs. the energy of excitation could be used to classify different microscopic features. In particular, the power law exponent ranges between 1 and 3, depending on the nature of nonlinearity. We also provide a theoretical interpretation of the collected data using models for clapping and hysteretic nonlinearities. - Highlights: • Several materials exhibit a nontrivial nonlinear elastic behavior which can be ascribed to different physical sources. • The quantitative nonlinear response is dependent on the type of microstructure present in the material. • A nonlinear indicator could be defined which depends on the excitation energy of the sample. • Assuming a power law dependence, the exponent depends on the microstructure of the material and could evolve in time. • Experimental results on concrete are discussed and a theoretical description is proposed.

Isomorphs in the phase diagram of a model liquid without inverse power law repulsion

DEFF Research Database (Denmark)

Veldhorst, Arnold Adriaan; Bøhling, Lasse; Dyre, J. C.

2012-01-01

scattering function are calculated. The results are shown to reflect a hidden scale invariance; despite its exponential repulsion the Buckingham potential is well approximated by an inverse power-law plus a linear term in the region of the first peak of the radial distribution function. As a consequence...... the dynamics of the viscous Buckingham liquid is mimicked by a corresponding model with purely repulsive inverse-power-law interactions. The results presented here closely resemble earlier results for Lennard-Jones type liquids, demonstrating that the existence of strong correlations and isomorphs does...... not depend critically on the mathematical form of the repulsion being an inverse power law....

Analysis of the geomagnetic activity of the Dst index and self-affine fractals using wavelet transforms

Directory of Open Access Journals (Sweden)

H. L. Wei

2004-01-01

Full Text Available The geomagnetic activity of the Dst index is analyzed using wavelet transforms and it is shown that the Dst index possesses properties associated with self-affine fractals. For example, the power spectral density obeys a power-law dependence on frequency, and therefore the Dst index can be viewed as a self-affine fractal dynamic process. In fact, the behaviour of the Dst index, with a Hurst exponent H≈0.5 (power-law exponent β≈2 at high frequency, is similar to that of Brownian motion. Therefore, the dynamical invariants of the Dst index may be described by a potential Brownian motion model. Characterization of the geomagnetic activity has been studied by analysing the geomagnetic field using a wavelet covariance technique. The wavelet covariance exponent provides a direct effective measure of the strength of persistence of the Dst index. One of the advantages of wavelet analysis is that many inherent problems encountered in Fourier transform methods, such as windowing and detrending, are not necessary.

Power-law modulation of the scalar power spectrum from a heavy field with a monomial potential

Science.gov (United States)

Huang, Qing-Guo; Pi, Shi

2018-04-01

The effects of heavy fields modulate the scalar power spectrum during inflation. We analytically calculate the modulations of the scalar power spectrum from a heavy field with a separable monomial potential, i.e. V(phi)~ phin. In general the modulation is characterized by a power-law oscillation which is reduced to the logarithmic oscillation in the case of n=2.

The enforcement order for the law for arrangement of surrounding areas of power generating facilities

International Nuclear Information System (INIS)

1980-01-01

This rule is established under the provisions of the law for the redevelopment of the surrounding areas of power generating facilities. Persons who install power generating facilities under the law include general electric power enterprises and wholesale electric power enterprises defined under the electric enterprises act and the Power Reactor and Nuclear Fuel Development Corporation. The scale of these facilities defined under the law is 350,000 kilo-watts output for atomic and thermal power generating facilities, 10,000 kilo-watts output for the facilities utilizing geothermal energy, 100,000 kilo-watts output for facilities whose main fuel is coal, and 1,000 kilo-watts output for hydraulic power generating facilities, etc. The facilities closely related to atomic power generation include the reprocessing and examination facilities of fuel materials spent in atomic power reactors, the reactors installed by the Japan Atomic Energy Research Institute for studying on the safety of atomic power reactors, the experimental fast reactors and the uranium enrichment facilities established by the Power Reactor and Nuclear Fuel Development Corporation. The public facilities in this rule are those for communication, sport and recreation, environment hygiene, education and culture, medicine, social welfare, fire fighting, etc. Governors of prefectures who intend to get approval under the law shall file redevelopment plans to the competent minister through the Minister of the International Trade and Industry. (Okada, K.)

Convergence of spectral methods for nonlinear conservation laws. Final report

International Nuclear Information System (INIS)

Tadmor, E.

1987-08-01

The convergence of the Fourier method for scalar nonlinear conservation laws which exhibit spontaneous shock discontinuities is discussed. Numerical tests indicate that the convergence may (and in fact in some cases must) fail, with or without post-processing of the numerical solution. Instead, a new kind of spectrally accurate vanishing viscosity is introduced to augment the Fourier approximation of such nonlinear conservation laws. Using compensated compactness arguments, it is shown that this spectral viscosity prevents oscillations, and convergence to the unique entropy solution follows

Macro impact of the law on prevention and control of atmospheric pollution on power industry development

Energy Technology Data Exchange (ETDEWEB)

Wang, Z. [State Power Corporation (China). Dept. of Science, Technology and Environment

2001-07-01

The newly revised and enlarged main contents of China's Law of Prevention and Control of Atmospheric Pollution, which came into force on 1 September 2000, are described. The macro impacts of the law on the power industry development are analyzed mainly in respect to power demand and readjustment of power structure and layout, clean production and pollution control level, scientific management of environmental protection, in accordance with law as well as changes of construction and operation costs. Several questions worthy to be noted in course of implementation of the new law are enumerated. 1 tab.

The experimental viscosity and calculated relative viscosity of liquid In-Sn allcoys

International Nuclear Information System (INIS)

Wu, A.Q.; Guo, L.J.; Liu, C.S.; Jia, E.G.; Zhu, Z.G.

2007-01-01

The experimental measured viscosity of liquid pure Sn, In 20 Sn 80 and In 80 Sn 20 alloys was studied, and to make a comparison, the calculated relative viscosity based on the pair distribution functions, g(r), has also been studied. There is one peak in each experimental viscosity and calculated relative-viscosity curve of liquid pure Sn about 1000 deg. C. One valley appears in each experimental viscosity and calculated viscosity curve of liquid In 20 Sn 80 alloy about 700 deg. C. There is no abnormal behavior on In 80 Sn 20 alloy. The behavior of experimental viscosity and calculated relative viscosity is coincident with each other. Those results conformed that the temperature-induced structure anomalies reported before did take place

Explaining the power-law distribution of human mobility through transportation modality decomposition

Science.gov (United States)

Zhao, Kai; Musolesi, Mirco; Hui, Pan; Rao, Weixiong; Tarkoma, Sasu

2015-03-01

Human mobility has been empirically observed to exhibit Lévy flight characteristics and behaviour with power-law distributed jump size. The fundamental mechanisms behind this behaviour has not yet been fully explained. In this paper, we propose to explain the Lévy walk behaviour observed in human mobility patterns by decomposing them into different classes according to the different transportation modes, such as Walk/Run, Bike, Train/Subway or Car/Taxi/Bus. Our analysis is based on two real-life GPS datasets containing approximately 10 and 20 million GPS samples with transportation mode information. We show that human mobility can be modelled as a mixture of different transportation modes, and that these single movement patterns can be approximated by a lognormal distribution rather than a power-law distribution. Then, we demonstrate that the mixture of the decomposed lognormal flight distributions associated with each modality is a power-law distribution, providing an explanation to the emergence of Lévy Walk patterns that characterize human mobility patterns.

A study on the sensitivity depletion laws for rhodium self-powered neutron detectors

International Nuclear Information System (INIS)

Kim, Gil Gon

1999-02-01

The rhodium self-powered neutron detectors (SPND) in a reactor core provide the operator with the on-line 3-dimensional nuclear power distribution. The signal produced by rhodium SPND is interpreted into the local neutron flux by using a sensitivity depletion law and the local neutron flux is interpreted into the local power by using a power conversion factor. This work on the sensitivity depletion laws for rhodium self-powered neutron detectors (SPND) is performed to improve the uncertainty of the sensitivity depletion law used in ABB-CE reactors employing a rhodium SPND and to develop a calculational tool for providing the sensitivity depletion laws to interpret the signal of the newly designed rhodium SPND into the local neutron flux. The calculational tools for a time dependent neutron flux distribution in the rhodium emitter during depletion and for a time dependent beta escape probability that a beta generated in the emitter is escaped into the collector were developed. Due to the cost, the exposure to the radiation, and the longer fuel cycle, there is a strong incentive that the loading density of an in-core instrumentation is reduced and the lifetime of the detector is lengthened. These objectives can be achieved by reducing the uncertainty which is amplified as it depletes. The calculational tools above provide the sensitivity depletion law and show the reduction of the uncertainty to about 1 % in interpreting the signal into the local neutron flux compared to the method employed by ABB-CE. The reduction in the uncertainty of 1 % in interpreting the signal into the local neutron flux is equivalent to the reduction in the uncertainty of 1 % or more in interpreting the signal into the local power and to the extension of the lifetime of rhodium SPND to about 10 % as reported by ABB-CE

Non-power law behavior of the radial profile of phase-space density of halos

International Nuclear Information System (INIS)

Popolo, A. Del

2011-01-01

We study the pseudo phase-space density, ρ(r)/σ 3 (r), of ΛCDM dark matter halos with and without baryons (baryons+DM, and pure DM), by using the model introduced in Del Popolo (2009), which takes into account the effect of dynamical friction, ordered and random angular momentum, baryons adiabatic contraction and dark matter baryons interplay. We examine the radial dependence of ρ(r)/σ 3 (r) over 9 orders of magnitude in radius for structures on galactic and cluster of galaxies scales. We find that ρ(r)/σ 3 (r) is approximately a power-law only in the range of halo radius resolved by current simulations (down to 0.1% of the virial radius) while it has a non-power law behavior below the quoted scale, with inner profiles changing with mass. The non-power-law behavior is more evident for halos constituted both of dark matter and baryons while halos constituted just of dark matter and with angular momentum chosen to reproduce a Navarro-Frenk-White (NFW) density profile, are characterized by an approximately power-law behavior. The results of the present paper lead to conclude that density profiles of the NFW type are compatible with a power-law behavior of ρ(r)/σ 3 (r), while those flattening to the halo center, like those found in Del Popolo (2009) or the Einasto profile, or the Burkert profile, cannot produce radial profile of the pseudo-phase-space density that are power-laws at all radii. The results argue against universality of the pseudo phase-space density and as a consequence argue against universality of density profiles constituted by dark matter and baryons as also discussed in Del Popolo (2009)

How Power-Laws Re-Write The Rules Of Cyber Warfare

Directory of Open Access Journals (Sweden)

David L. Bibighaus

2015-12-01

Full Text Available All warfare contains and element of randomness. This article will argue that, the kind uncertainty encountered in cyber warfare (Power-Law randomness is fundamentally different from the uncertainty the military has evolved to deal with in the physical world (Gaussian-Randomness. The article will explain the difference between these two kinds of randomness, and how cyber weapons appear to operate under Power-Law randomness. It then will show how in cyberspace, key aspects of strategic thought are based on a flaws assumption of randomness. Finally, this article shall argue that if the American military is going to be effective in cyberspace, it must re-examine the way the military assumes risk, recruits is forces, plans for war and maintains the peace.

Fall Velocities of Hydrometeors in the Atmosphere: Refinements to a Continuous Analytical Power Law.

Science.gov (United States)

Khvorostyanov, Vitaly I.; Curry, Judith A.

2005-12-01

This paper extends the previous research of the authors on the unified representation of fall velocities for both liquid and crystalline particles as a power law over the entire size range of hydrometeors observed in the atmosphere. The power-law coefficients are determined as continuous analytical functions of the Best or Reynolds number or of the particle size. Here, analytical expressions are formulated for the turbulent corrections to the Reynolds number and to the power-law coefficients that describe the continuous transition from the laminar to the turbulent flow around a falling particle. A simple analytical expression is found for the correction of fall velocities for temperature and pressure. These expressions and the resulting fall velocities are compared with observations and other calculations for a range of ice crystal habits and sizes. This approach provides a continuous analytical power-law description of the terminal velocities of liquid and crystalline hydrometeors with sufficiently high accuracy and can be directly used in bin-resolving models or incorporated into parameterizations for cloud- and large-scale models and remote sensing techniques.

Role of medium heterogeneity and viscosity contrast in miscible flow regimes and mixing zone growth: A computational pore-scale approach

Science.gov (United States)

Afshari, Saied; Hejazi, S. Hossein; Kantzas, Apostolos

2018-05-01

Miscible displacement of fluids in porous media is often characterized by the scaling of the mixing zone length with displacement time. Depending on the viscosity contrast of fluids, the scaling law varies between the square root relationship, a sign for dispersive transport regime during stable displacement, and the linear relationship, which represents the viscous fingering regime during an unstable displacement. The presence of heterogeneities in a porous medium significantly affects the scaling behavior of the mixing length as it interacts with the viscosity contrast to control the mixing of fluids in the pore space. In this study, the dynamics of the flow and transport during both unit and adverse viscosity ratio miscible displacements are investigated in heterogeneous packings of circular grains using pore-scale numerical simulations. The pore-scale heterogeneity level is characterized by the variations of the grain diameter and velocity field. The growth of mixing length is employed to identify the nature of the miscible transport regime at different viscosity ratios and heterogeneity levels. It is shown that as the viscosity ratio increases to higher adverse values, the scaling law of mixing length gradually shifts from dispersive to fingering nature up to a certain viscosity ratio and remains almost the same afterwards. In heterogeneous media, the mixing length scaling law is observed to be generally governed by the variations of the velocity field rather than the grain size. Furthermore, the normalization of mixing length temporal plots with respect to the governing parameters of viscosity ratio, heterogeneity, medium length, and medium aspect ratio is performed. The results indicate that mixing length scales exponentially with log-viscosity ratio and grain size standard deviation while the impact of aspect ratio is insignificant. For stable flows, mixing length scales with the square root of medium length, whereas it changes linearly with length during

A Note on the Invariance Properties and Conservation Laws of the Kadomstev—Petviashvili Equation with Power Law Nonlinearity

International Nuclear Information System (INIS)

Bokhari A H; Zaman F D; Fakhar K; Kara A H

2011-01-01

First, we studied the invariance properties of the Kadomstev—Petviashvili equation with power law nonlinearity. Then, we determined the complete class of conservation laws and stated the corresponding conserved densities which are useful in finding the conserved quantities of the equation. The point symmetry generators were also used to reduce the equation to an exact solution and to verify the invariance properties of the conserved flows. (general)

Problems and legislative remedies of the parallel law systems in Japan for nuclear power reactors

International Nuclear Information System (INIS)

Irie, Kazutomo

2011-01-01

There are two established laws governing nuclear power reactors in Japan. One is the Electricity Utilities Industry Law, which regulates the nuclear power reactors, and the other is the so-called 'Reactor Regulation Law', which dually regulates the reactors in some phases. When a graded approach on the regulation of nuclear reactors was adopted, it extended over these two laws and was legislatively imperfect. Such imperfection created problems from the beginning. Also, the original regulatory structures presented by these laws had become obscure during the operation process of the graded regulation. The situation becomes further complicated by the revision of these laws in recent years. It appears that the trait of the regulatory procedural structure of the Electricity Utilities Industry Law has been weakened. As there is a pressing need to review the entire regulatory structure and to propose a unified regulatory system by combining these laws, this paper examines the merits and demerits of combining these laws under a unified regulation. (author)

Power-law cross-correlations estimation under heavy tails

Czech Academy of Sciences Publication Activity Database

Krištoufek, Ladislav

2016-01-01

Roč. 40, č. 1 (2016), s. 163-172 ISSN 1007-5704 R&D Projects: GA ČR(CZ) GP14-11402P Institutional support: RVO:67985556 Keywords : Power-law cross-correlations * Heavy tails * Monte Carlo study Subject RIV: AH - Economics Impact factor: 2.784, year: 2016 http://library.utia.cas.cz/separaty/2016/E/kristoufek-0472030.pdf

Strong Law of Large Numbers for Countable Markov Chains Indexed by an Infinite Tree with Uniformly Bounded Degree

Directory of Open Access Journals (Sweden)

Bao Wang

2014-01-01

Full Text Available We study the strong law of large numbers for the frequencies of occurrence of states and ordered couples of states for countable Markov chains indexed by an infinite tree with uniformly bounded degree, which extends the corresponding results of countable Markov chains indexed by a Cayley tree and generalizes the relative results of finite Markov chains indexed by a uniformly bounded tree.

Determination of Viscosity-Average Molecular Weight of Chitosan using Intrinsic Viscosity Measurement

International Nuclear Information System (INIS)

Norzita Yacob; Norhashidah Talip; Maznah Mahmud

2011-01-01

Molecular weight of chitosan can be determined by different techniques such as Gel Permeation Chromatography (GPC), Static Light Scattering (SLS) and intrinsic viscosity measurement. Determination of molecular weight by intrinsic viscosity measurement is a simple method for characterization of chitosan. Different concentrations of chitosan were prepared and measurement was done at room temperature. The flow time data was used to calculate the intrinsic viscosity by extrapolating the reduced viscosity to zero concentration. The value of intrinsic viscosity was then recalculated into the viscosity-average molecular weight using Mark-Houwink equation. (author)

Power laws and inverse motion modelling: application to turbulence measurements from satellite images

Directory of Open Access Journals (Sweden)

Pablo D. Mininni

2012-01-01

Full Text Available In the context of tackling the ill-posed inverse problem of motion estimation from image sequences, we propose to introduce prior knowledge on flow regularity given by turbulence statistical models. Prior regularity is formalised using turbulence power laws describing statistically self-similar structure of motion increments across scales. The motion estimation method minimises the error of an image observation model while constraining second-order structure function to behave as a power law within a prescribed range. Thanks to a Bayesian modelling framework, the motion estimation method is able to jointly infer the most likely power law directly from image data. The method is assessed on velocity fields of 2-D or quasi-2-D flows. Estimation accuracy is first evaluated on a synthetic image sequence of homogeneous and isotropic 2-D turbulence. Results obtained with the approach based on physics of fluids outperform state-of-the-art. Then, the method analyses atmospheric turbulence using a real meteorological image sequence. Selecting the most likely power law model enables the recovery of physical quantities, which are of major interest for turbulence atmospheric characterisation. In particular, from meteorological images we are able to estimate energy and enstrophy fluxes of turbulent cascades, which are in agreement with previous in situ measurements.

Melter feed viscosity during conversion to glass: Comparison between low-activity waste and high-level waste feeds

Energy Technology Data Exchange (ETDEWEB)

Jin, Tongan [Pacific Northwest National Laboratory, Richland Washington; Chun, Jaehun [Pacific Northwest National Laboratory, Richland Washington; Dixon, Derek R. [Pacific Northwest National Laboratory, Richland Washington; Kim, Dongsang [Pacific Northwest National Laboratory, Richland Washington; Crum, Jarrod V. [Pacific Northwest National Laboratory, Richland Washington; Bonham, Charles C. [Pacific Northwest National Laboratory, Richland Washington; VanderVeer, Bradley J. [Pacific Northwest National Laboratory, Richland Washington; Rodriguez, Carmen P. [Pacific Northwest National Laboratory, Richland Washington; Weese, Brigitte L. [Pacific Northwest National Laboratory, Richland Washington; Schweiger, Michael J. [Pacific Northwest National Laboratory, Richland Washington; Kruger, Albert A. [U.S. Department of Energy, Office of River Protection, Richland Washington; Hrma, Pavel [Pacific Northwest National Laboratory, Richland Washington

2017-12-07

During nuclear waste vitrification, a melter feed (generally a slurry-like mixture of a nuclear waste and various glass forming and modifying additives) is charged into the melter where undissolved refractory constituents are suspended together with evolved gas bubbles from complex reactions. Knowledge of flow properties of various reacting melter feeds is necessary to understand their unique feed-to-glass conversion processes occurring within a floating layer of melter feed called a cold cap. The viscosity of two low-activity waste (LAW) melter feeds were studied during heating and correlated with volume fractions of undissolved solid phase and gas phase. In contrast to the high-level waste (HLW) melter feed, the effects of undissolved solid and gas phases play comparable roles and are required to represent the viscosity of LAW melter feeds. This study can help bring physical insights to feed viscosity of reacting melter feeds with different compositions and foaming behavior in nuclear waste vitrification.

The rate coefficients of unimolecular reactions in the systems with power-law distributions

Science.gov (United States)

Yin, Cangtao; Guo, Ran; Du, Jiulin

2014-08-01

The rate coefficient formulae of unimolecular reactions are generalized to the systems with the power-law distributions based on nonextensive statistics, and the power-law rate coefficients are derived in the high and low pressure limits, respectively. The numerical analyses are made of the rate coefficients as functions of the ν-parameter, the threshold energy, the temperature and the number of degrees of freedom. We show that the new rate coefficients depend strongly on the ν-parameter different from one (thus from a Boltzmann-Gibbs distribution). Two unimolecular reactions, CH3CO→CH3+CO and CH3NC→CH3CN, are taken as application examples to calculate their power-law rate coefficients, which obtained with the ν-parameters slightly different from one can be exactly in agreement with all the experimental studies on these two reactions in the given temperature ranges.

Extremal dependencies and rank correlations in power law networks

NARCIS (Netherlands)

Volkovich, Y.; Litvak, Nelli; Zwart, B.; Jie, Z.

2009-01-01

We analyze dependencies in complex networks characterized by power laws (Web sample, Wikipedia sample and a preferential attachment graph) using statistical techniques from the extreme value theory and the theory of multivariate regular variation. To the best of our knowledge, this is the first

Sharing Powers Within Exclusive Competences: Rethinking EU Antitrust Law Enforcement

OpenAIRE

Van Cleynenbreugel, Pieter

2016-01-01

Although the establishment of competition rules forms part of the EU’s exclusive competences, the application and enforcement of those rules has always been shared consistently between the EU and its Member States.The sharing of enforcement powers is conceptualised traditionally as a delegation of the exercise of exclusively conferred competences. The Court of Justice of the European Union’s case law in the context of EU antitrust law enforcement nevertheless raises profound questions as to t...

The mean first passage time in an energy-diffusion controlled regime with power-law distributions

International Nuclear Information System (INIS)

Zhou, Yanjun; Du, Jiulin

2013-01-01

Based on the mean first passage time (MFPT) theory, we derive an expression of the MFPT in an energy-diffusion controlled regime with a power-law distribution. We discuss the finite barrier effect (i.e. the thermal energy k B T is not small with respect to the potential barrier E b ) and compare it with Kramers’ infinite barrier result both in a power-law distribution and in a Maxwell–Boltzmann distribution. It is shown that the MFPT with a power-law distribution extends Kramers’ low-damping result to a relatively low barrier. We pay attention to the energy-diffusion controlled regime, which is of great interest in the context of Josephson junctions, and study how the power-law parameter κ affects the current distribution function in experiments with Josephson junctions. (paper)

The Legal Regime of Nuclear Power Satellites-A Problem at the Cross-Roads of Nuclear Law and Space Law

International Nuclear Information System (INIS)

Courteix, S.

1992-01-01

The number of nuclear-powered satellites rises constantly and, recalling the fear generated by the crash of the Cosmos 954 satellite, the author points out that radioactive debris falling on earth could represent as great a hazard as accidental releases of radioactive material from land-based nuclear installations. Such satellites, therefore, can be governed by both space law and nuclear law. On the basis of international conventions applicable in the two fields and also with reference to the Law of the Sea and environmental law, the article analyses preventive and radiation protection measures as well as emergency plans and also raises the problem of liability and compensation for damage. (NEA)

Legal basis of energy economy. Collection of important laws and regulations of the amended power economy law. 7. ed.; Rechtsgrundlagen der Energiewirtschaft. Sammlung wichtiger Gesetze und Vorschriften zum novellierten Energiewirtschaftsrecht

Energy Technology Data Exchange (ETDEWEB)

Herrmann, B.J.; Schweers, E.

2007-07-01

The book under consideration is an actual collection of important laws and regulations according to the amended power economy law. It is the 7th edition and contains components of the European and national cartel law. Furthermore, the power economy law, the regulations of mains access, and the regulations of mains fee are revised editorial. The book consist of four main chapters: (a) General energy law; (b) Bylaws to energy economical laws; (c) Law of privileged energy supports; (d) cartel law.

Power-law cosmic expansion in f(R) gravity models

International Nuclear Information System (INIS)

Goheer, Naureen; Larena, Julien; Dunsby, Peter K. S.

2009-01-01

We show that within the class of f(R) gravity theories, Friedmann-Lemaitre-Robertson-Walker power-law perfect fluid solutions only exist for R n gravity. This significantly restricts the set of exact cosmological solutions which have similar properties to what is found in standard general relativity.

Statistical Properties of the Australian ``All Ordinaries'' Index

Science.gov (United States)

Storer, Robin; Gunner, Susan M.

Price changes of the primary index of the Australian Stock Market are analyzed over a period of about 20 years. The probability distribution of the relative changes in the index (returns) satisfies a distribution which is almost independent of the time interval chosen to measure the change. The distribution is consistent with the analysis of New York and other stock exchanges and also seems to satisfy a power law with exponent consistent with an inverse cubic law. If the data are separated into positive and negative returns this conclusion is not justified, particularly for the rising market. Thus there seems to be a significant asymmetry in the distribution.

Discovery of Power-Law Growth in the Self-Renewal of Heterogeneous Glioma Stem Cell Populations.

Directory of Open Access Journals (Sweden)

Michiya Sugimori

Full Text Available Accumulating evidence indicates that cancer stem cells (CSCs drive tumorigenesis. This suggests that CSCs should make ideal therapeutic targets. However, because CSC populations in tumors appear heterogeneous, it remains unclear how CSCs might be effectively targeted. To investigate the mechanisms by which CSC populations maintain heterogeneity during self-renewal, we established a glioma sphere (GS forming model, to generate a population in which glioma stem cells (GSCs become enriched. We hypothesized, based on the clonal evolution concept, that with each passage in culture, heterogeneous clonal sublines of GSs are generated that progressively show increased proliferative ability.To test this hypothesis, we determined whether, with each passage, glioma neurosphere culture generated from four different glioma cell lines become progressively proliferative (i.e., enriched in large spheres. Rather than monitoring self-renewal, we measured heterogeneity based on neurosphere clone sizes (#cells/clone. Log-log plots of distributions of clone sizes yielded a good fit (r>0.90 to a straight line (log(% total clones = k*log(#cells/clone indicating that the system follows a power-law (y = xk with a specific degree exponent (k = -1.42. Repeated passaging of the total GS population showed that the same power-law was maintained over six passages (CV = -1.01 to -1.17. Surprisingly, passage of either isolated small or large subclones generated fully heterogeneous populations that retained the original power-law-dependent heterogeneity. The anti-GSC agent Temozolomide, which is well known as a standard therapy for glioblastoma multiforme (GBM, suppressed the self-renewal of clones, but it never disrupted the power-law behavior of a GS population.Although the data above did not support the stated hypothesis, they did strongly suggest a novel mechanism that underlies CSC heterogeneity. They indicate that power-law growth governs the self-renewal of heterogeneous

On stability and monotonicity requirements of finite difference approximations of stochastic conservation laws with random viscosity

KAUST Repository

Pettersson, Per

2013-05-01

The stochastic Galerkin and collocation methods are used to solve an advection-diffusion equation with uncertain and spatially varying viscosity. We investigate well-posedness, monotonicity and stability for the extended system resulting from the Galerkin projection of the advection-diffusion equation onto the stochastic basis functions. High-order summation-by-parts operators and weak imposition of boundary conditions are used to prove stability of the semi-discrete system.It is essential that the eigenvalues of the resulting viscosity matrix of the stochastic Galerkin system are positive and we investigate conditions for this to hold. When the viscosity matrix is diagonalizable, stochastic Galerkin and stochastic collocation are similar in terms of computational cost, and for some cases the accuracy is higher for stochastic Galerkin provided that monotonicity requirements are met. We also investigate the total spatial operator of the semi-discretized system and its impact on the convergence to steady-state. © 2013 Elsevier B.V.

On stability and monotonicity requirements of finite difference approximations of stochastic conservation laws with random viscosity

KAUST Repository

Pettersson, Per; Doostan, Alireza; Nordströ m, Jan

2013-01-01

The stochastic Galerkin and collocation methods are used to solve an advection-diffusion equation with uncertain and spatially varying viscosity. We investigate well-posedness, monotonicity and stability for the extended system resulting from the Galerkin projection of the advection-diffusion equation onto the stochastic basis functions. High-order summation-by-parts operators and weak imposition of boundary conditions are used to prove stability of the semi-discrete system.It is essential that the eigenvalues of the resulting viscosity matrix of the stochastic Galerkin system are positive and we investigate conditions for this to hold. When the viscosity matrix is diagonalizable, stochastic Galerkin and stochastic collocation are similar in terms of computational cost, and for some cases the accuracy is higher for stochastic Galerkin provided that monotonicity requirements are met. We also investigate the total spatial operator of the semi-discretized system and its impact on the convergence to steady-state. © 2013 Elsevier B.V.

The Power Laws of Violence against Women: Rescaling Research and Policies

Science.gov (United States)

Kappler, Karolin E.; Kaltenbrunner, Andreas

2012-01-01

Background Violence against Women –despite its perpetuation over centuries and its omnipresence at all social levels– entered into social consciousness and the general agenda of Social Sciences only recently, mainly thanks to feminist research, campaigns, and general social awareness. The present article analyzes in a secondary analysis of German prevalence data on Violence against Women, whether the frequency and severity of Violence against Women can be described with power laws. Principal Findings Although the investigated distributions all resemble power-law distributions, a rigorous statistical analysis accepts this hypothesis at a significance level of 0.1 only for 1 of 5 cases of the tested frequency distributions and with some restrictions for the severity of physical violence. Lowering the significance level to 0.01 leads to the acceptance of the power-law hypothesis in 2 of the 5 tested frequency distributions and as well for the severity of domestic violence. The rejections might be mainly due to the noise in the data, with biases caused by self-reporting, errors through rounding, desirability response bias, and selection bias. Conclusion Future victimological surveys should be designed explicitly to avoid these deficiencies in the data to be able to clearly answer the question whether Violence against Women follows a power-law pattern. This finding would not only have statistical implications for the processing and presentation of the data, but also groundbreaking consequences on the general understanding of Violence against Women and policy modeling, as the skewed nature of the underlying distributions makes evident that Violence against Women is a highly disparate and unequal social problem. This opens new questions for interdisciplinary research, regarding the interplay between environmental, experimental, and social factors on victimization. PMID:22768348

Rehabilitation after stroke: predictive power of Barthel Index versus a cognitive and a motor index

DEFF Research Database (Denmark)

Engberg, A; Bentzen, L; Garde, B

1995-01-01

The aim of the present study was to investigate the predictive power of ratings of Barthel Index at Day 40 post stroke, compared with and/or combined with simultaneous ratings from a mobility scale (EG motor index) and a rather simple cognitive test scale (CT50). The parameter to be individually...

Effect of Qingnao tablet on blood viscosity of rat model of blood stasis induced by epinephrine

Science.gov (United States)

Xie, Guoqi; Hao, Shaojun; Ma, Zhenzhen; Liu, Xiaobin; Li, Jun; Li, Wenjun; Zhang, Zhengchen

2018-04-01

To establish a rat model of blood stasis with adrenaline (Adr) subcutaneous injection and ice bath stimulation. The effects of different doses on the blood viscosity of blood stasis model rats were observed. The rats were randomly divided into 6 groups: blank control group (no model), model group, positive control group, high, middle and low dose group. The whole blood viscosity and plasma viscosity were detected by blood viscosity instrument. Compared with the blank group, model group, high shear, low shear whole blood viscosity and plasma viscosity were significantly increased, TT PT significantly shortened, APTT was significantly prolonged, FIB increased significantly, indicating that the model was successful. Compared with the model group, can significantly reduce the Naoluotong group (cut, low cut). Qingnaopian high dose group (low cut), middle dose group (cut, low shear blood viscosity) (Pgroup, high dose group (Pgroup (Pblood rheology of blood stasis mice abnormal index, decrease the blood viscosity, blood stasis has certain hemostatic effect.

Around power law for PageRank components in Buckley-Osthus model of web graph

OpenAIRE

Gasnikov, Alexander; Zhukovskii, Maxim; Kim, Sergey; Noskov, Fedor; Plaunov, Stepan; Smirnov, Daniil

2017-01-01

In the paper we investigate power law for PageRank components for the Buckley-Osthus model for web graph. We compare different numerical methods for PageRank calculation. With the best method we do a lot of numerical experiments. These experiments confirm the hypothesis about power law. At the end we discuss real model of web-ranking based on the classical PageRank approach.

Dense power-law networks and simplicial complexes

Science.gov (United States)

Courtney, Owen T.; Bianconi, Ginestra

2018-05-01

There is increasing evidence that dense networks occur in on-line social networks, recommendation networks and in the brain. In addition to being dense, these networks are often also scale-free, i.e., their degree distributions follow P (k ) ∝k-γ with γ ∈(1 ,2 ] . Models of growing networks have been successfully employed to produce scale-free networks using preferential attachment, however these models can only produce sparse networks as the numbers of links and nodes being added at each time step is constant. Here we present a modeling framework which produces networks that are both dense and scale-free. The mechanism by which the networks grow in this model is based on the Pitman-Yor process. Variations on the model are able to produce undirected scale-free networks with exponent γ =2 or directed networks with power-law out-degree distribution with tunable exponent γ ∈(1 ,2 ) . We also extend the model to that of directed two-dimensional simplicial complexes. Simplicial complexes are generalization of networks that can encode the many body interactions between the parts of a complex system and as such are becoming increasingly popular to characterize different data sets ranging from social interacting systems to the brain. Our model produces dense directed simplicial complexes with power-law distribution of the generalized out-degrees of the nodes.

Densities, viscosities, and refractive indexes for {C2H5CO2(CH2)2CH3+C6H13OH+C6H6} at T=308.15 K

International Nuclear Information System (INIS)

Casas, Herminio; Garcia-Garabal, Sandra; Segade, Luisa; Cabeza, Oscar.; Franjo, Carlos; Jimenez, Eulogio

2003-01-01

In this work we present densities, kinematic viscosities, and refractive indexes of the ternary system {C 2 H 5 CO 2 (CH 2 ) 2 CH 3 +C 6 H 13 OH+C 6 H 6 } and the corresponding binary mixtures {C 2 H 5 CO 2 (CH 2 ) 2 CH 3 +C 6 H 6 }, {C 2 H 5 CO 2 (CH 2 ) 2 CH 3 +C 6 H 13 OH}, and {C 6 H 13 OH+C 6 H 6 }. All data have been measured at T=308.15 K and atmospheric pressure over the whole composition range. The excess molar volumes, dynamic viscosity deviations, and changes of the refractive index on mixing were calculated from experimental measurements. The results for binary mixtures were fitted to a polynomial relationship to estimate the coefficients and standard deviations. The Cibulka equation has been used to correlate the experimental values of ternary mixtures. Also, the experimental values obtained for the ternary mixture were used to test the empirical methods of Kohler, Jacob and Fitzner, Colinet, Tsao and Smith, Toop, Scatchard et al., and Hillert. These methods predict excess properties of the ternary mixtures from those of the involved binary mixtures. The results obtained for dynamic viscosities of the binary mixtures were used to test the semi-empirical relations of Grunberg-Nissan, McAllister, Auslaender, and Teja-Rice. Finally, the experimental refractive indexes were compared with the predicted results for the Lorentz-Lorenz, Gladstone-Dale, Wiener, Heller, and Arago-Biot equations. In all cases, we give the standard deviation between the experimental data and that calculated with the above named relations

Second-order small-disturbance solutions for hypersonic flow over power-law bodies

Science.gov (United States)

Townsend, J. C.

1975-01-01

Similarity solutions were found which give the adiabatic flow of an ideal gas about two-dimensional and axisymmetric power-law bodies at infinite Mach number to second order in the body slenderness parameter. The flow variables were expressed as a sum of zero-order and perturbation similarity functions for which the axial variations in the flow equations separated out. The resulting similarity equations were integrated numerically. The solutions, which are universal functions, are presented in graphic and tabular form. To avoid a singularity in the calculations, the results are limited to body power-law exponents greater than about 0.85 for the two-dimensional case and 0.75 for the axisymmetric case. Because of the entropy layer induced by the nose bluntness (for power-law bodies other than cones and wedges), only the pressure function is valid at the body surface. The similarity results give excellent agreement with the exact solutions for inviscid flow over wedges and cones having half-angles up to about 20 deg. They give good agreement with experimental shock-wave shapes and surface-pressure distributions for 3/4-power axisymmetric bodies, considering that Mach number and boundary-layer displacement effects are not included in the theory.

Emergence of power-law in a market with mixed models

Science.gov (United States)

Ali Saif, M.; Gade, Prashant M.

2007-10-01

We investigate the problem of wealth distribution from the viewpoint of asset exchange. Robust nature of Pareto's law across economies, ideologies and nations suggests that this could be an outcome of trading strategies. However, the simple asset exchange models fail to reproduce this feature. A Yardsale (YS) model in which amount put on the bet is a fraction of minimum of the two players leads to condensation of wealth in hands of some agent while theft and fraud (TF) model in which the amount to be exchanged is a fraction of loser's wealth leads to an exponential distribution of wealth. We show that if we allow few agents to follow a different model than others, i.e., there are some agents following TF model while rest follow YS model, it leads to distribution with power-law tails. Similar effect is observed when one carries out transactions for a fraction of one's wealth using TF model and for the rest YS model is used. We also observe a power-law tail in wealth distribution if we allow the agents to follow either of the models with some probability.

Vapor pressure, density, viscosity and refractive index of dimethyl sulfoxide + 1,4-dimethylbenzene system

Directory of Open Access Journals (Sweden)

OANA CIOCIRLAN

2008-01-01

Full Text Available This paper reports the experimental results of isothermal vapor–liquid equilibrium data between 303.15 and 333.15 K, and densities, viscosities, refractive indices from 298.15 to 323.15 K of the dimethyl sulfoxide + 1,4-dimethylbenzene system over the entire range of mixture composition. The obtained PTX data were correlated by the Wilson and NRTL models and estimated by the UNIFAC model. The excess Gibbs energy and activity coefficients were calculated and compared with others excess properties. Excess molar volumes, viscosity deviations and deviations in refractivity were calculated from the experimental data; all the computed quantities were fitted to the Redlich–Kister equation. The resulting excess functions were interpreted in terms of structure and interactions.

Learning curves in highly skilled chess players: a test of the generality of the power law of practice.

Science.gov (United States)

Howard, Robert W

2014-09-01

The power law of practice holds that a power function best interrelates skill performance and amount of practice. However, the law's validity and generality are moot. Some researchers argue that it is an artifact of averaging individual exponential curves while others question whether the law generalizes to complex skills and to performance measures other than response time. The present study tested the power law's generality to development over many years of a very complex cognitive skill, chess playing, with 387 skilled participants, most of whom were grandmasters. A power or logarithmic function best fit grouped data but individuals showed much variability. An exponential function usually was the worst fit to individual data. Groups differing in chess talent were compared and a power function best fit the group curve for the more talented players while a quadratic function best fit that for the less talented. After extreme amounts of practice, a logarithmic function best fit grouped data but a quadratic function best fit most individual curves. Individual variability is great and the power law or an exponential law are not the best descriptions of individual chess skill development. Copyright © 2014 Elsevier B.V. All rights reserved.

Power-law behavior in complex organizational communication networks during crisis

Science.gov (United States)

Uddin, Shahadat; Murshed, Shahriar Tanvir Hasan; Hossain, Liaquat

2011-08-01

Communication networks can be described as patterns of contacts which are created due to the flow of messages and information shared among participating actors. Contemporary organizations are now commonly viewed as dynamic systems of adaptation and evolution containing several parts, which interact with one another both in internal and in external environment. Although there is limited consensus among researchers on the precise definition of organizational crisis, there is evidence of shared meaning: crisis produces individual crisis, crisis can be associated with positive or negative conditions, crises can be situations having been precipitated quickly or suddenly or situations that have developed over time and are predictable etc. In this research, we study the power-law behavior of an organizational email communication network during crisis from complexity perspective. Power law simply describes that, the probability that a randomly selected node has k links (i.e. degree k) follows P(k)∼k, where γ is the degree exponent. We used social network analysis tools and techniques to analyze the email communication dataset. We tested two propositions: (1) as organization goes through crisis, a few actors, who are prominent or more active, will become central, and (2) the daily communication network as well as the actors in the communication network exhibit power-law behavior. Our preliminary results support these two propositions. The outcome of this study may provide significant advancement in exploring organizational communication network behavior during crisis.

Instabilities in power law gradient hardening materials

DEFF Research Database (Denmark)

Niordson, Christian Frithiof; Tvergaard, Viggo

2005-01-01

Tension and compression instabilities are investigated for specimens with dimensions in the micron range. A finite strain generalization of a higher order strain gradient plasticity theory is implemented in a finite element scheme capable of modeling power law hardening materials. Effects...... of gradient hardening are found to delay the onset of localization under plane strain tension, and significantly reduce strain gradients in the localized zone. For plane strain compression gradient hardening is found to increase the load-carrying capacity significantly....

Determination of viscosity-average molecular weight of chitosan using intrinsic viscosity measurement

International Nuclear Information System (INIS)

Norzita Yacob; Norhashidah Talip; Maznah Mahmud; Nurul Aizam Idayu Mat Sani; Nor Akma Samsuddin; Norafifah Ahmad Fabillah

2013-01-01

Determination of molecular weight by intrinsic viscosity measurement is a simple method for characterization of chitosan. To study the effect of radiation on molecular weight, chitosan was first irradiated using electron beam at different doses prior to measurement. Different concentrations of chitosan were prepared and measurement was done at room temperature. The flow time data was used to calculate the intrinsic viscosity by extrapolating the reduced viscosity to zero concentration. The value of intrinsic viscosity was then recalculated into the viscosity-average molecular weight using Mark-Houwink equation. (Author)

THE FUNDAMENTAL SOLUTIONS FOR MULTI-TERM MODIFIED POWER LAW WAVE EQUATIONS IN A FINITE DOMAIN.

Science.gov (United States)

Jiang, H; Liu, F; Meerschaert, M M; McGough, R J

2013-01-01

Fractional partial differential equations with more than one fractional derivative term in time, such as the Szabo wave equation, or the power law wave equation, describe important physical phenomena. However, studies of these multi-term time-space or time fractional wave equations are still under development. In this paper, multi-term modified power law wave equations in a finite domain are considered. The multi-term time fractional derivatives are defined in the Caputo sense, whose orders belong to the intervals (1, 2], [2, 3), [2, 4) or (0, n ) ( n > 2), respectively. Analytical solutions of the multi-term modified power law wave equations are derived. These new techniques are based on Luchko's Theorem, a spectral representation of the Laplacian operator, a method of separating variables and fractional derivative techniques. Then these general methods are applied to the special cases of the Szabo wave equation and the power law wave equation. These methods and techniques can also be extended to other kinds of the multi-term time-space fractional models including fractional Laplacian.

Development and characterization of adjustable refractive index scattering epoxy acrylate polymer layers

Science.gov (United States)

Eiselt, Thomas; Preinfalk, Jan; Gleißner, Uwe; Lemmer, Uli; Hanemann, Thomas

2017-03-01

Several polymer films for improved optical properties in optoelectronic devices are presented. In such optical applications, it is sometimes important to have a film with an adjusted refractive index, scattering properties, and a low surface roughness. These diffusing films can be used to increase the efficiency of optoelectronic components, such as organic light-emitting diodes. Three different epoxy acrylate mixtures containing Syntholux 291 EA, bisphenol A glycerolate dimethacrylate, and Sartomer SR 348 L are characterized and optimized with different additives. The adjustable refractive index of the material is achieved by chemical doping using 9-vinylcarbazole. Titanium nanoparticles in the mixtures generate light scattering and increase the refractive index additionally. A high-power stirrer is used to mix and disperse all chemical substances together to a homogenous mixture. The viscosity behavior of the mixtures is an important property for the selection of the production method and, therefore, the viscosity measurement results are presented. After the mixing, the monomer mixture is applied on glass substrates by screen printing. To initiate polymerization, the produced films are irradiated for 10 min with ultraviolet radiation and heat. Transmission measurements of the polymer matrix and roughness measurements complement the characterization.

Propagation of waves in a randomly inhomogeneous medium with strongly developed fluctuations. III. Arbitrary power-law noise correlation function

International Nuclear Information System (INIS)

Adzhemyan, L.Ts.; Vasil'ev, A.N.; Pis'mak, Yu.M.

1988-01-01

The investigation of the infrared behavior of the propagator of a light wave in a randomly inhomogeneous medium with massless Gaussian noise is continued. The infrared representation of the propagator for correlation function D varphi (k)∼k -2 is generalized to the case of an arbitrary power-law noise correlation function is rigorously established in the first two orders of the infrared asymptotic behavior by construction of a suitable R operation. As a consequence, the results are generalized to the case of critical opalescence, when D varphi (k)∼k -2+η , where η ∼ 0.03 is the Fisher index

Finite sample properties of power-law cross-correlations estimators

Czech Academy of Sciences Publication Activity Database

Krištoufek, Ladislav

2015-01-01

Roč. 419, č. 1 (2015), s. 513-525 ISSN 0378-4371 R&D Projects: GA ČR(CZ) GP14-11402P Keywords : power-law cross-correlations * long - term memory * econophysics Subject RIV: AH - Economics Impact factor: 1.785, year: 2015 http://library.utia.cas.cz/separaty/2014/E/kristoufek-0433530.pdf

Power laws and fragility in flow networks.

Science.gov (United States)

Shore, Jesse; Chu, Catherine J; Bianchi, Matt T

2013-01-01

What makes economic and ecological networks so unlike other highly skewed networks in their tendency toward turbulence and collapse? Here, we explore the consequences of a defining feature of these networks: their nodes are tied together by flow. We show that flow networks tend to the power law degree distribution (PLDD) due to a self-reinforcing process involving position within the global network structure, and thus present the first random graph model for PLDDs that does not depend on a rich-get-richer function of nodal degree. We also show that in contrast to non-flow networks, PLDD flow networks are dramatically more vulnerable to catastrophic failure than non-PLDD flow networks, a finding with potential explanatory power in our age of resource- and financial-interdependence and turbulence.

A New Vogel-Like Law: Ionic Conductivity, Dielectric Relaxation and Viscosity Near the Glass Transition

National Research Council Canada - National Science Library

Bendler, John

2001-01-01

A model, based on defect diffusion, is developed that describes temperature and pressure dependence of dielectric relaxation, ionic conductivity and viscosity of glass-forming liquids near the glass...

On Origin of Power-Law Distributions in Self-Organized Criticality from Random Walk Treatment

International Nuclear Information System (INIS)

Cao Xiaofeng; Deng Zongwei; Yang Chunbin

2008-01-01

The origin of power-law distributions in self-organized criticality is investigated by treating the variation of the number of active sites in the system as a stochastic process. An avalanche is then regarded as a first-return random walk process in a one-dimensional lattice. We assume that the variation of the number of active sites has three possibilities in each update: to increase by 1 with probability f 1 , to decrease by 1 with probability f 2 , or remain unchanged with probability 1-f 1 -f 2 . This mimics the dynamics in the system. Power-law distributions of the lifetime are found when the random walk is unbiased with equal probability to move in opposite directions. This shows that power-law distributions in self-organized criticality may be caused by the balance of competitive interactions.

Power law load dependence of atomic friction

OpenAIRE

Fusco, C.; Fasolino, A.

2004-01-01

We present a theoretical study of the dynamics of a tip scanning a graphite surface as a function of the applied load. From the analysis of the lateral forces, we extract the friction force and the corrugation of the effective tip-surface interaction potential. We find both the friction force and potential amplitude to have a power-law dependence on applied load with exponent similar to1.6. We interpret these results as characteristic of sharp undeformable tips in contrast to the case of macr...

Power Politics and the Rule of Law in Post-Dayton Bosnia

Directory of Open Access Journals (Sweden)

Timothy Donais

2013-06-01

Full Text Available Over the past two decades, therule of law has emerged as a key priority within contemporary peacebuildingefforts. Drawing on examples from post-Dayton Bosnia, this article examines theimpact of rule of law reform efforts on broader patterns of power and politicalauthority in peacebuilding contexts. It suggests that in the case of Bosnia,the use of rule of law strategies to restructure political life has largelyfailed. Thus, despite some notable achievements on the rule of law front, thecore dynamics of Bosnia’s political conflict remain intact, and country’s peaceprocess is as fragile as ever. The article concludes by noting that charting acourse between accepting the political status quo and fundamentallytransforming it requires more nuanced approaches that advance the rule of laweven while accepting its limits as an instrument of deep politicaltransformation.

Regularized lattice Boltzmann model for immiscible two-phase flows with power-law rheology

Science.gov (United States)

Ba, Yan; Wang, Ningning; Liu, Haihu; Li, Qiang; He, Guoqiang

2018-03-01

In this work, a regularized lattice Boltzmann color-gradient model is developed for the simulation of immiscible two-phase flows with power-law rheology. This model is as simple as the Bhatnagar-Gross-Krook (BGK) color-gradient model except that an additional regularization step is introduced prior to the collision step. In the regularization step, the pseudo-inverse method is adopted as an alternative solution for the nonequilibrium part of the total distribution function, and it can be easily extended to other discrete velocity models no matter whether a forcing term is considered or not. The obtained expressions for the nonequilibrium part are merely related to macroscopic variables and velocity gradients that can be evaluated locally. Several numerical examples, including the single-phase and two-phase layered power-law fluid flows between two parallel plates, and the droplet deformation and breakup in a simple shear flow, are conducted to test the capability and accuracy of the proposed color-gradient model. Results show that the present model is more stable and accurate than the BGK color-gradient model for power-law fluids with a wide range of power-law indices. Compared to its multiple-relaxation-time counterpart, the present model can increase the computing efficiency by around 15%, while keeping the same accuracy and stability. Also, the present model is found to be capable of reasonably predicting the critical capillary number of droplet breakup.

New power economy law for electricity and gas

International Nuclear Information System (INIS)

Heller, W.

2004-01-01

Since August 4, 2003, the so-called Directives on Speeding up Common Regulations for the Single Market for Electricity and Common Regulations for the Single Market for Gas have been in force (Official Journal of the European Communities L 176/37). These Directives must be translated into national law by July 1, 2004. The national legislative process in Germany for a Power Economy Act adapted accordingly is presented and evaluated. (orig.)

Power-law behaviour evaluation from foreign exchange market data using a wavelet transform method

Science.gov (United States)

Wei, H. L.; Billings, S. A.

2009-09-01

Numerous studies in the literature have shown that the dynamics of many time series including observations in foreign exchange markets exhibit scaling behaviours. A simple new statistical approach, derived from the concept of the continuous wavelet transform correlation function (WTCF), is proposed for the evaluation of power-law properties from observed data. The new method reveals that foreign exchange rates obey power-laws and thus belong to the class of self-similarity processes.

Power-law behaviour evaluation from foreign exchange market data using a wavelet transform method

Energy Technology Data Exchange (ETDEWEB)

Wei, H.L., E-mail: w.hualiang@sheffield.ac.u [Department of Automatic Control and Systems Engineering, the University of Sheffield, Mappin Street, Sheffield, S1 3JD (United Kingdom); Billings, S.A., E-mail: s.billings@sheffield.ac.u [Department of Automatic Control and Systems Engineering, the University of Sheffield, Mappin Street, Sheffield, S1 3JD (United Kingdom)

2009-09-07

Numerous studies in the literature have shown that the dynamics of many time series including observations in foreign exchange markets exhibit scaling behaviours. A simple new statistical approach, derived from the concept of the continuous wavelet transform correlation function (WTCF), is proposed for the evaluation of power-law properties from observed data. The new method reveals that foreign exchange rates obey power-laws and thus belong to the class of self-similarity processes.

Power-law behaviour evaluation from foreign exchange market data using a wavelet transform method

International Nuclear Information System (INIS)

Wei, H.L.; Billings, S.A.

2009-01-01

Numerous studies in the literature have shown that the dynamics of many time series including observations in foreign exchange markets exhibit scaling behaviours. A simple new statistical approach, derived from the concept of the continuous wavelet transform correlation function (WTCF), is proposed for the evaluation of power-law properties from observed data. The new method reveals that foreign exchange rates obey power-laws and thus belong to the class of self-similarity processes.

The Dynamics of Power laws: Fitness and Aging in Preferential Attachment Trees

Science.gov (United States)

Garavaglia, Alessandro; van der Hofstad, Remco; Woeginger, Gerhard

2017-09-01

Continuous-time branching processes describe the evolution of a population whose individuals generate a random number of children according to a birth process. Such branching processes can be used to understand preferential attachment models in which the birth rates are linear functions. We are motivated by citation networks, where power-law citation counts are observed as well as aging in the citation patterns. To model this, we introduce fitness and age-dependence in these birth processes. The multiplicative fitness moderates the rate at which children are born, while the aging is integrable, so that individuals receives a finite number of children in their lifetime. We show the existence of a limiting degree distribution for such processes. In the preferential attachment case, where fitness and aging are absent, this limiting degree distribution is known to have power-law tails. We show that the limiting degree distribution has exponential tails for bounded fitnesses in the presence of integrable aging, while the power-law tail is restored when integrable aging is combined with fitness with unbounded support with at most exponential tails. In the absence of integrable aging, such processes are explosive.

Air-chemistry "turbulence": power-law scaling and statistical regularity

Directory of Open Access Journals (Sweden)

H.-m. Hsu

2011-08-01

Full Text Available With the intent to gain further knowledge on the spectral structures and statistical regularities of surface atmospheric chemistry, the chemical gases (NO, NO₂, NO_x, CO, SO₂, and O₃ and aerosol (PM₁₀ measured at 74 air quality monitoring stations over the island of Taiwan are analyzed for the year of 2004 at hourly resolution. They represent a range of surface air quality with a mixed combination of geographic settings, and include urban/rural, coastal/inland, plain/hill, and industrial/agricultural locations. In addition to the well-known semi-diurnal and diurnal oscillations, weekly, and intermediate (20 ~ 30 days peaks are also identified with the continuous wavelet transform (CWT. The spectra indicate power-law scaling regions for the frequencies higher than the diurnal and those lower than the diurnal with the average exponents of −5/3 and −1, respectively. These dual-exponents are corroborated with those with the detrended fluctuation analysis in the corresponding time-lag regions. These exponents are mostly independent of the averages and standard deviations of time series measured at various geographic settings, i.e., the spatial inhomogeneities. In other words, they possess dominant universal structures. After spectral coefficients from the CWT decomposition are grouped according to the spectral bands, and inverted separately, the PDFs of the reconstructed time series for the high-frequency band demonstrate the interesting statistical regularity, −3 power-law scaling for the heavy tails, consistently. Such spectral peaks, dual-exponent structures, and power-law scaling in heavy tails are important structural information, but their relations to turbulence and mesoscale variability require further investigations. This could lead to a better understanding of the processes controlling air quality.

Determination of viscosity of fayalite slags for kv model and measurements by means of inclined plane

International Nuclear Information System (INIS)

Bazan, V.; Goni, C.; Castella, L.; Brandaleze, E.; Verdeja, L. F.; Parra, R.

2006-01-01

The viscosity of the lands represents one of the most relevant variables of most of the processes metallurgical and kinetics of the refine operations, since it is one of the decisive factors of the efficiency in the reactions between metal and lag, as much as slag-refractory. In the last decades, the mathematical models of different metallurgical processes have established methods to predict viscosity of mixtures of oxides fused to high temperatures in function of the chemical composition. The model developed by Toguri, based on the data reported by Johasen and Winterhager et al has proposed the Kv model. The used index it is similar to the relationship used in the steel industry like the basicity index. It is presented in this work values determined of viscosity in experimental form by means of the technique of inclined plane. (Author)

Cluster tails for critical power-law inhomogeneous random graphs

NARCIS (Netherlands)

van der Hofstad, R.; Kliem, S.; van Leeuwaarden, J.S.H.

2018-01-01

Recently, the scaling limit of cluster sizes for critical inhomogeneous random graphs of rank-1 type having finite variance but infinite third moment degrees was obtained in Bhamidi et al. (Ann Probab 40:2299–2361, 2012). It was proved that when the degrees obey a power law with exponent τ∈ (3 , 4)

Hypersonic aerodynamic characteristics of a family of power-law, wing body configurations

Science.gov (United States)

Townsend, J. C.

1973-01-01

The configurations analyzed are half-axisymmetric, power-law bodies surmounted by thin, flat wings. The wing planform matches the body shock-wave shape. Analytic solutions of the hypersonic small disturbance equations form a basis for calculating the longitudinal aerodynamic characteristics. Boundary-layer displacement effects on the body and the wing upper surface are approximated. Skin friction is estimated by using compressible, laminar boundary-layer solutions. Good agreement was obtained with available experimental data for which the basic theoretical assumptions were satisfied. The method is used to estimate the effects of power-law, fineness ratio, and Mach number variations at full-scale conditions. The computer program is included.

Bounds and inequalities relating h-index, g-index, e-index and generalized impact factor: an improvement over existing models.

Science.gov (United States)

Abbas, Ash Mohammad

2012-01-01

In this paper, we describe some bounds and inequalities relating h-index, g-index, e-index, and generalized impact factor. We derive the bounds and inequalities relating these indexing parameters from their basic definitions and without assuming any continuous model to be followed by any of them. We verify the theorems using citation data for five Price Medalists. We observe that the lower bound for h-index given by Theorem 2, [formula: see text], g ≥ 1, comes out to be more accurate as compared to Schubert-Glanzel relation h is proportional to C(2/3)P(-1/3) for a proportionality constant of 1, where C is the number of citations and P is the number of papers referenced. Also, the values of h-index obtained using Theorem 2 outperform those obtained using Egghe-Liang-Rousseau power law model for the given citation data of Price Medalists. Further, we computed the values of upper bound on g-index given by Theorem 3, g ≤ (h + e), where e denotes the value of e-index. We observe that the upper bound on g-index given by Theorem 3 is reasonably tight for the given citation record of Price Medalists.

“Slimming” of power-law tails by increasing market returns

Science.gov (United States)

Sornette, D.

2002-06-01

We introduce a simple generalization of rational bubble models which removes the fundamental problem discovered by Lux and Sornette (J. Money, Credit and Banking, preprint at http://xxx.lanl.gov/abs/cond-mat/9910141) that the distribution of returns is a power law with exponent discount rate rδ, the distribution of returns of the observable price, sum of the bubble component and of the fundamental price, exhibits an intermediate tail with an exponent which can be larger than 1. This regime r> rδ corresponds to a generalization of the rational bubble model in which the fundamental price is no more given by the discounted value of future dividends. We explain how this is possible. Our model predicts that, the higher is the market remuneration r above the discount rate, the larger is the power-law exponent and thus the thinner is the tail of the distribution of price returns.

Nonlinear damping for vibration isolation of microsystems using shear thickening fluid

Science.gov (United States)

Iyer, S. S.; Vedad-Ghavami, R.; Lee, H.; Liger, M.; Kavehpour, H. P.; Candler, R. N.

2013-06-01

This work reports the measurement and analysis of nonlinear damping of micro-scale actuators immersed in shear thickening fluids (STFs). A power-law damping term is added to the linear second-order model to account for the shear-dependent viscosity of the fluid. This nonlinear model is substantiated by measurements of oscillatory motion of a torsional microactuator. At high actuation forces, the vibration velocity amplitude saturates. The model accurately predicts the nonlinear damping characteristics of the STF using a power-law index extracted from independent rheology experiments. This result reveals the potential to use STFs as adaptive, passive dampers for vibration isolation of microelectromechanical systems.

Simple inflationary quintessential model. II. Power law potentials

Science.gov (United States)

de Haro, Jaume; Amorós, Jaume; Pan, Supriya

2016-09-01

The present work is a sequel of our previous work [Phys. Rev. D 93, 084018 (2016)] which depicted a simple version of an inflationary quintessential model whose inflationary stage was described by a Higgs-type potential and the quintessential phase was responsible due to an exponential potential. Additionally, the model predicted a nonsingular universe in past which was geodesically past incomplete. Further, it was also found that the model is in agreement with the Planck 2013 data when running is allowed. But, this model provides a theoretical value of the running which is far smaller than the central value of the best fit in ns , r , αs≡d ns/d l n k parameter space where ns, r , αs respectively denote the spectral index, tensor-to-scalar ratio and the running of the spectral index associated with any inflationary model, and consequently to analyze the viability of the model one has to focus in the two-dimensional marginalized confidence level in the allowed domain of the plane (ns,r ) without taking into account the running. Unfortunately, such analysis shows that this model does not pass this test. However, in this sequel we propose a family of models runs by a single parameter α ∈[0 ,1 ] which proposes another "inflationary quintessential model" where the inflation and the quintessence regimes are respectively described by a power law potential and a cosmological constant. The model is also nonsingular although geodesically past incomplete as in the cited model. Moreover, the present one is found to be more simple compared to the previous model and it is in excellent agreement with the observational data. In fact, we note that, unlike the previous model, a large number of the models of this family with α ∈[0 ,1/2 ) match with both Planck 2013 and Planck 2015 data without allowing the running. Thus, the properties in the current family of models compared to its past companion justify its need for a better cosmological model with the successive

Browse Title Index

African Journals Online (AJOL)

Items 201 - 250 of 531 ... Journal Home > Advanced Search > Browse Title Index ... thermal conductivity and viscosity in a flat plate solar collector, Abstract PDF .... similarity method in unsteady two-dimensional MHD boundary layer on the body ...

Mapping the Power of Law Professors: The Role of Scientific and Social Capital

Science.gov (United States)

Bühlmann, Felix; Benz, Pierre; Mach, André; Rossier, Thierry

2017-01-01

As a scientific discipline and profession, law has been for centuries at the heart of social and political power of many Western societies. Professors of law, as influential representatives of the profession, are important powerbrokers between academia, politics and the corporate world. Their influence is based on scientific reputation,…

IMPLEMENTATION OF ENERGY LAW OF HYBRID POWER STATION FOR SOCIAL WELFARE

Directory of Open Access Journals (Sweden)

Dyah Ayu Widowati

2014-11-01

Full Text Available This study was aimed to investigate the Implementation of Energy Law of Hybrid Power Station for Social Welfare in Pantai Baru. The problem formulations are the management and utilization of hybrid power station in Pantai Baru and implementation of energy law of hybrid power station for social welfare in the fields of economy and information in Pantai Baru. Based on data analysis it is concluded that the management of hybrid power station in Pantai Baru is performed collaboratively between government and the society. The existence of hybrid power station in pantai baru has positive impacts in economy and information. Penelitian ini meneliti Pelaksanaan Hukum Energi Pembangkit Listrik Tenaga Hibrid untuk Kesejahteraan Rakyat di Bidang Ekonomi dan Informasi di Pantai Baru. Masalah yang diteliti adalah bentuk pengelolaan dan pemanfaatan pembangkit listrik tenaga hibrid di Pantai Baru dan pelaksanaan hukum energi pembangkit listrik tenaga hibrid untuk kesejahteraan rakyat di bidang ekonomi dan informasi di Pantai Baru. Berdasarkan analisis data dapat disimpulkan bahwa pengelolaan pembangkit listrik tenaga hibrid yang ada di pantai baru dilakukan secara kolaboratif, antara pemerintah dengan masyarakat. Kehadiran pembangkit listrik tenaga hibrid yang ada di pantai baru telah memberikan dampak positif di bidang ekonomi dan informasi.

Law concerning water and nuclear power station licensing

International Nuclear Information System (INIS)

Anon.

1985-01-01

The competent water authority, within the purview of the legal provisions concerning water is entitled to define a maximum of radioactive contamination of cooling water taken from and re-fed into the Rhine river, and is entitled to make such limit form part of the permit granted to a nuclear power station (here: Biblis B reactor). This right is not overruled by sections 45, 46 of the Rad. Protection Ordinance which determine dose limits (among others also for radioactivity released through waste water), and which state the competent licensing authority under atomic energy law to be entitled to set higher or lower limits by discretion. The provisions of sections 45 ff Rad. Prot. Ordinance are to be interpreted to mean that since the competent authority in accordance with section 46, sub-sections (2) and (5) Rad. Prot. Ordinance is given the right to define maximum acceptable radioactivity release through water discharge, it many also define the lowest limit of contamination and is hence entitled to declare discharged cooling water not to fall under atomic energy law, but rather under the law relating to water management. (orig.) [de

A Study on Sunward-propagating Alfvénic Fluctuations with a Power-law Spectrum (SAFP) Observed by the WIND Spacecraft

Science.gov (United States)

Wang, X.; Wu, H.; Tu, C. Y.; Wang, L.; He, J.; Tian, H.

2017-12-01

Sunward-propagating Alfvénic fluctuations with a power-law spectrum (SAFP) have been recently reported to be a significant physical phenomenon in the solar wind. However, some characteristics of these SAFPs are still unknown. Here we develop a new method for identifying SAFPs. In this method, we can identify all SAFPs with any value of θRB (angle between the global magnetic field and the radial direction). We find 508 SAFPs using the WIND spacecraft observation from 1995 to 2014. We also find that SAFP occurs more frequently when θRB equals 90°. The spectral index with an average -1.77 changes continuously from -2.18 for the parallel to -1.71 for the perpendicular. SAFPs occur more at the maximum and tend to be observed in the slow solar wind especially at solar minimum. We also apply the new method to identify anti-sunward-propagating Alfvénic fluctuations with a power-law spectrum (AFP) for comparison. The number of SAFPs is much less than AFPs, and the cases with local bending account for about half of all observed cases. SAFPs have a preference for negative σc and ASFs for positive. The statistical results demonstrate that SAFP has a steeper and weaker power spectrum and present a weaker power anisotropy than that of AFP. These new results may reveal new insight into the physical mechanism of the SAFP generation.

Study on the evaluation index of active power reserve

Science.gov (United States)

Guo, Xiaorui; Liu, Jiantao; Wang, Ke; Min, Lu

2018-01-01

Based on the role of active reserve at different time scales, divides the evaluation dimension of active reserve. Analysis the calculation principle of traditional reliability index such as probability of system safety, lack of power shortage and electricity shortage expectancy, and studies the applicability of these indicators to evaluate the reserve capacity on different dimensions. Resolves the evaluation index of active reserve capacity from the dimensions of time dimension, spatial dimension, system state, risk degree and economy, then construct evaluation index of active reserve capacity.

Mapping Power Law Distributions in Digital Health Social Networks: Methods, Interpretations, and Practical Implications.

Science.gov (United States)

van Mierlo, Trevor; Hyatt, Douglas; Ching, Andrew T

2015-06-25

Social networks are common in digital health. A new stream of research is beginning to investigate the mechanisms of digital health social networks (DHSNs), how they are structured, how they function, and how their growth can be nurtured and managed. DHSNs increase in value when additional content is added, and the structure of networks may resemble the characteristics of power laws. Power laws are contrary to traditional Gaussian averages in that they demonstrate correlated phenomena. The objective of this study is to investigate whether the distribution frequency in four DHSNs can be characterized as following a power law. A second objective is to describe the method used to determine the comparison. Data from four DHSNs—Alcohol Help Center (AHC), Depression Center (DC), Panic Center (PC), and Stop Smoking Center (SSC)—were compared to power law distributions. To assist future researchers and managers, the 5-step methodology used to analyze and compare datasets is described. All four DHSNs were found to have right-skewed distributions, indicating the data were not normally distributed. When power trend lines were added to each frequency distribution, R(2) values indicated that, to a very high degree, the variance in post frequencies can be explained by actor rank (AHC .962, DC .975, PC .969, SSC .95). Spearman correlations provided further indication of the strength and statistical significance of the relationship (AHC .987. DC .967, PC .983, SSC .993, Ppower distributions across multiple DHSNs, each addressing a unique condition. Results indicate that despite vast differences in theme, content, and length of existence, DHSNs follow properties of power laws. The structure of DHSNs is important as it gives insight to researchers and managers into the nature and mechanisms of network functionality. The 5-step process undertaken to compare actor contribution patterns can be replicated in networks that are managed by other organizations, and we conjecture that

Viscosity of diluted suspensions of vegetal particles in water

Directory of Open Access Journals (Sweden)

Szydłowska Adriana

2017-01-01

Full Text Available Viscosity and rheological behaviour of sewage as well as sludge are essential while designing apparatuses and operations employed in the sewage treatment process and its processing. With reference to these substances, the bio-suspensions samples of three size fractions ((i 150÷212 μm, (ii 106÷150 μm and (iii below106 μm of dry grass in water with solid volume fraction 8%, 10% and 11% were prepared. After twenty four hours prior to their preparation time, the suspension samples underwent rheometeric measurements with the use of a rotational rheometer with coaxial cylinders. On the basis of the obtained results, flow curves were plotted and described with both the power model and Herschel-Bulkley model. Moreover, the viscosity of the studied substances was determined that allowed to conclude that the studied bio-suspensions display features of viscoelastic fluids. The experimentally established viscosity was compared to the calculated one according to Manley and Manson equation, recommended in the literature. It occurred that the measured viscosity values substantially exceed the calculation viscosity values, even by 105 times. The observations suggest that it stems from water imbibition of fibrous vegetal particles, which causes their swelling and decreases the amount of liquid phase in the suspension.

Power Law Distributions in the Experiment for Adjustment of the Ion Source of the NBI System

International Nuclear Information System (INIS)

Han Xiaopu; Hu Chundong

2005-01-01

The experiential adjustment process in an experiment on the ion source of the neutral beam injector system for the HT-7 Tokamak is reported in this paper. With regard to the data obtained in the same condition, in arranging the arc current intensities of every shot with a decay rank, the distributions of the arc current intensity correspond to the power laws, and the distribution obtained in the condition with the cryo-pump corresponds to the double Pareto distribution. Using the similar study method, the distributions of the arc duration are close to the power laws too. These power law distributions are formed rather naturally instead of being the results of purposeful seeking

Electron-processing technology: A promising application for the viscose industry

Science.gov (United States)

Stepanik, T. M.; Rajagopal, S.; Ewing, D.; Whitehouse, R.

1998-06-01

In marketing its IMPELA ® line of high power, high-throughput industrial accelerators, Atomic Energy of Canada Limited (AECL) is working with viscose (rayon) companies world-wide to integrate electron-processing technology as part of the viscose manufacturing process. The viscose industry converts cellulose wood pulp into products such as staple fiber, filament, cord, film, packaging, and non-edible sausage casings. This multibillion dollar industry is currently suffering from high production costs, and is facing increasingly stringent environmental regulations. The use of electron-treated pulp can significantly lower production costs and can provide equally significant environmental benefits. This paper describes our current understanding of the benefits of using electron-treated pulp in this process, and AECL's efforts in developing this technology.

Prevention of damage and 'residual risk' in nuclear power laws

International Nuclear Information System (INIS)

Greipl, C.

1992-01-01

The concept of prevention of damage within the framework of nuclear power laws includes averting danger for the protection of third parties and preventing risks for the partial protection of third parties with the proviso that still a desire to use the concept 'residual risk' in addition, it should be limited, on the grounds of what can be reasonably expected, to those risks which cannot be reduced any further by the government, i.e. to risks which the public in general and third parties ('actually') must accept. In the future, questions regarding safety systems should be taken into account exclusively withing the context of 'what is necessary for protection against damage in keeping with the latest developments in science and technology' and not at the discretion of the law in denying permission according to Article 7 Paragraph 2 Atomic Energy Law. (orig.) [de

Orbits in elementary, power-law galaxy bars - 1. Occurrence and role of single loops

Science.gov (United States)

Struck, Curtis

2018-05-01

Orbits in galaxy bars are generally complex, but simple closed loop orbits play an important role in our conceptual understanding of bars. Such orbits are found in some well-studied potentials, provide a simple model of the bar in themselves, and may generate complex orbit families. The precessing, power ellipse (p-ellipse) orbit approximation provides accurate analytic orbit fits in symmetric galaxy potentials. It remains useful for finding and fitting simple loop orbits in the frame of a rotating bar with bar-like and symmetric power-law potentials. Second-order perturbation theory yields two or fewer simple loop solutions in these potentials. Numerical integrations in the parameter space neighbourhood of perturbation solutions reveal zero or one actual loops in a range of such potentials with rising rotation curves. These loops are embedded in a small parameter region of similar, but librating orbits, which have a subharmonic frequency superimposed on the basic loop. These loops and their librating companions support annular bars. Solid bars can be produced in more complex potentials, as shown by an example with power-law indices varying with radius. The power-law potentials can be viewed as the elementary constituents of more complex potentials. Numerical integrations also reveal interesting classes of orbits with multiple loops. In two-dimensional, self-gravitating bars, with power-law potentials, single-loop orbits are very rare. This result suggests that gas bars or oval distortions are unlikely to be long-lived, and that complex orbits or three-dimensional structure must support self-gravitating stellar bars.

Non-coulombic effective power-law potential for the heavy quarkoniums

Energy Technology Data Exchange (ETDEWEB)

Barik, N; Jena, S N [Utkal Univ., Bhubaneswar (India). Dept. of Physics

1980-12-01

An effective power-law potential of the form V(r) = 6.08 r/sup 0/sup(.)/sup 106/ - 6.41 is found to describe satisfactorily the gross features of the mass spectra and the leptonic width ratios of the cc and bb systems in a flavour-independent manner.

Networks of power in digital copyright law and policy political salience, expertise and the legislative process

CERN Document Server

Farrand, Benjamin

2014-01-01

In this book, Benjamin Farrand employs an interdisciplinary approach that combines legal analysis with political theory to explore the development of copyright law in the EU. Farrand utilises Foucault's concept of Networks of Power and Culpepper's Quiet Politics to assess the adoption and enforcement of copyright law in the EU, including the role of industry representative, cross-border licensing, and judicial approaches to territorial restrictions. Focusing in particular on legislative initiatives concerning copyright, digital music and the internet, Networks of Power in Digital Copyright Law and Policy: Political Salience, Expertise and the Legislative Process demonstrates the connection between copyright law and complex network relationships. This book presents an original socio-political theoretical framework for assessing developments in copyright law that will interest researchers and post-graduate students of law and politics, as well as those more particularly concerned with political theory, EU and c...

Excess molar volume, viscosity, and refractive index study for the ternary mixture {2-methyl-2-butanol (1) + tetrahydrofuran (2) + propylamine (3)} at different temperatures. Application of the ERAS-model and Peng-Robinson-Stryjek-Vera equation of state

International Nuclear Information System (INIS)

Fattahi, M.; Iloukhani, H.

2010-01-01

Densities, viscosities, and refractive indices of the ternary mixture consist of {2-methyl-2-butanol (1) + tetrahydrofuran (THF) (2) + propylamine (3)} at a temperature of 298.15 K and related binary mixtures were measured at temperatures of (288.15, 298.15, and 308.15) K at ambient pressure. Data were used to calculate the excess molar volumes and the deviations of the viscosity and refractive index. The Redlich-Kister and the Cibulka equations were used for correlating binary and ternary properties, respectively. The ERAS-model has been applied for describing the binary and ternary excess molar volumes and also Peng-Robinson-Stryjek-Vera (PRSV) equation of state (EOS) has been used to predict the binary and ternary excess molar volumes and viscosities.

Effect of Yixinkangtai Capsule combined with diltiazem on endothelial function, blood viscosity and lipid metabolism in patients with unstable angina pectoris

Directory of Open Access Journals (Sweden)

Yu-Feng Yuan

2017-10-01

Full Text Available Objective: To discuss the effect of Yixinkangtai Capsule combined with diltiazem on endothelial function, blood viscosity and lipid metabolism in patients with unstable angina pectoris. Methods: A total of 150 patients with unstable angina pectoris who were treated in the hospital between February 2014 and February 2017 were divided into the control group (n=75 and the research group (n=75 according to the random number table method. Control group received clinical conventional therapy, research group received Yixinkangtai Capsule combined with diltiazem therapy on the basis of conventional therapy, and both groups received 3 months of treatment. Differences in endothelial function, blood viscosity and lipid metabolism were compared between the two groups of patients before and after treatment. Results: Before treatment, the differences in serum levels of endothelial function indexes, blood viscosity indexes and lipid metabolism indexes were not statistically significant between the two groups. After 3 months of treatment, serum NO level of research group was higher than that of control group while ET-1 level was lower than that of control group; serum blood viscosity index TXB2 content of research group was lower than that of control group while PGI2 content was higher than that of control group; serum lipid metabolism indexes TG, TC and LDL-C contents of research group were lower than those of control group while HDL-C content was higher than that of control group. Conclusion: Yixinkangtai Capsule combined with diltiazem therapy can effectively optimize the endothelial function, reduce the blood viscosity and balance the lipid metabolism in patients with unstable angina pectoris.

Finite-size effects in transcript sequencing count distribution: its power-law correction necessarily precedes downstream normalization and comparative analysis.

Science.gov (United States)

Wong, Wing-Cheong; Ng, Hong-Kiat; Tantoso, Erwin; Soong, Richie; Eisenhaber, Frank

2018-02-12

Though earlier works on modelling transcript abundance from vertebrates to lower eukaroytes have specifically singled out the Zip's law, the observed distributions often deviate from a single power-law slope. In hindsight, while power-laws of critical phenomena are derived asymptotically under the conditions of infinite observations, real world observations are finite where the finite-size effects will set in to force a power-law distribution into an exponential decay and consequently, manifests as a curvature (i.e., varying exponent values) in a log-log plot. If transcript abundance is truly power-law distributed, the varying exponent signifies changing mathematical moments (e.g., mean, variance) and creates heteroskedasticity which compromises statistical rigor in analysis. The impact of this deviation from the asymptotic power-law on sequencing count data has never truly been examined and quantified. The anecdotal description of transcript abundance being almost Zipf's law-like distributed can be conceptualized as the imperfect mathematical rendition of the Pareto power-law distribution when subjected to the finite-size effects in the real world; This is regardless of the advancement in sequencing technology since sampling is finite in practice. Our conceptualization agrees well with our empirical analysis of two modern day NGS (Next-generation sequencing) datasets: an in-house generated dilution miRNA study of two gastric cancer cell lines (NUGC3 and AGS) and a publicly available spike-in miRNA data; Firstly, the finite-size effects causes the deviations of sequencing count data from Zipf's law and issues of reproducibility in sequencing experiments. Secondly, it manifests as heteroskedasticity among experimental replicates to bring about statistical woes. Surprisingly, a straightforward power-law correction that restores the distribution distortion to a single exponent value can dramatically reduce data heteroskedasticity to invoke an instant increase in

[Relations between plasma-erythrocyte viscosity factors and ESR].

Science.gov (United States)

Cortinovis, A; Crippa, A; Crippa, M; Bosoni, T; Moratti, R

1992-09-01

The ESR is usually put in relationship: to the real density of the RBCs (erythrocytes) (difference between the RBC specific gravity and the plasma one), and to the resistance that the RBCs meet moving in a medium, which is due to the plasma viscosity and to the total external RBC surface. When the RBCs take shape of aggregates, their external surface is decreased and ESR increases. The most important plasma factor causing changes in ESR is the fibrinogen level followed by the plasma globulins and by the products arising from the tissue damage. The resistance that the RBCs meet moving in the plasma is well expressed by the measurement of the plasma-RBC viscosity considering that is inclusive of both factors that are the plasma viscosity and the external RBC surface. The plasma-RBC viscosity is the resultant of several factors: Fa = Fb - Fe - Fs - Fm, were: Fa is the resultant, Fb the attracting forces due to the proteic macromolecules, Fe the repulsing forces due the negative charges. Fs the repulsing forces due to the shear-stress, Fm the force which opposes itself against the surface tension of the aggregation; it depends on the RBC morphology and on the RBC rigidity. The ESR has been recently used like an index of the RBC aggregation. The Authors study the relationship between several hemorheological parameters and the ESR in infective and inflammatory processes.(ABSTRACT TRUNCATED AT 250 WORDS)

The United Kingdom Law on the authorisation of nuclear power stations

International Nuclear Information System (INIS)

Savinson, R.

1977-01-01

This paper explains the requirements of the law of the United Kingdom as to the authorisations needed to construct and operate nuclear power plants in Great Britain. For simplicity, the texts referred to apply to England and Wales, Scottish law differing in detail but not in principle. Implementation of this legal system is studied in particular from the viewpoint of the Central Electricity Generating Board (CEGB) which is at present the body exclusively responsible for generating and supplying electricity in England and Wales. (NEA) [fr

Rehabilitation after stroke: predictive power of Barthel Index versus a cognitive and a motor index

DEFF Research Database (Denmark)

Engberg, A; Bentzen, L; Garde, B

1995-01-01

The aim of the present study was to investigate the predictive power of ratings of Barthel Index at Day 40 post stroke, compared with and/or combined with simultaneous ratings from a mobility scale (EG motor index) and a rather simple cognitive test scale (CT50). The parameter to be individually...... predicted was the need for special living facilities and support at discharge from a rehabilitation hospital, as well as six months later; 53 stroke patients with age median 68 years were included in this prospective study. It was shown that a combination of Barthel Index and CT50 had a stronger predictive...

Power law distributions of patents as indicators of innovation.

Directory of Open Access Journals (Sweden)

Dion R J O'Neale

Full Text Available The total number of patents produced by a country (or the number of patents produced per capita is often used as an indicator for innovation. Here we present evidence that the distribution of patents amongst applicants within many countries is well-described by power laws with exponents that vary between 1.66 (Japan and 2.37 (Poland. We suggest that this exponent is a useful new metric for studying innovation. Using simulations based on simple preferential attachment-type rules that generate power laws, we find we can explain some of the variation in exponents between countries, with countries that have larger numbers of patents per applicant generally exhibiting smaller exponents in both the simulated and actual data. Similarly we find that the exponents for most countries are inversely correlated with other indicators of innovation, such as research and development intensity or the ubiquity of export baskets. This suggests that in more advanced economies, which tend to have smaller values of the exponent, a greater proportion of the total number of patents are filed by large companies than in less advanced countries.

Lack of association between systolic blood pressure and blood viscosity in normotensive healthy subjects.

Science.gov (United States)

Irace, Concetta; Carallo, Claudio; Scavelli, Faustina; Loprete, Antonio; Merante, Valentina; Gnasso, Agostino

2012-01-01

A direct relationship between blood pressure and viscosity has frequently been reported, although clear data are not available. To better understand the relationship between these two variables, we evaluated blood viscosity and blood pressure in a group of healthy subjects without cardiovascular risk factors. Healthy subjects were selected from participants in a campaign of prevention of cardiovascular disease (n = 103). They underwent blood sampling for measurement of plasma and blood viscosity, haematocrit, blood lipids and glucose. The quantity and distribution of body fat was assessed by body mass index and waist/hip ratio, respectively. Systolic blood pressure (SBP) correlated significantly with age (r = 0.222) and waist/hip ratio (r = 0.374). Diastolic blood pressure (DBP) correlated significantly with waist/hip ratio (r = 0.216), haematocrit (r = 0.333) and blood viscosity (r = 0.258). Multiple linear regression analyses demonstrated that the only variable significantly associated with SBP was age, while haematocrit was the only variable significantly associated with DBP. Blood viscosity was closely related to waist/hip ratio. These findings show that SBP, in healthy subjects, is not influenced by haematocrit and blood viscosity. In contrast, DBP is related to the values of haematocrit. Among classical cardiovascular risk factors, waist/hip ratio is closely related to blood viscosity.

Nonlinear quenches of power-law confining traps in quantum critical systems

International Nuclear Information System (INIS)

Collura, Mario; Karevski, Dragi

2011-01-01

We describe the coherent quantum evolution of a quantum many-body system with a time-dependent power-law confining potential. The amplitude of the inhomogeneous potential is driven in time along a nonlinear ramp which crosses a critical point. Using Kibble-Zurek-like scaling arguments we derive general scaling laws for the density of excitations and energy excess generated during the nonlinear sweep of the confining potential. It is shown that, with respect to the sweeping rate, the densities follow algebraic laws with exponents that depend on the space-time properties of the potential and on the scaling dimensions of the densities. We support our scaling predictions with both analytical and numerical results on the Ising quantum chain with an inhomogeneous transverse field varying in time.

A Simple BODIPY-Based Viscosity Probe for Imaging of Cellular Viscosity in Live Cells

Directory of Open Access Journals (Sweden)

Dongdong Su

2016-08-01

Full Text Available Intracellular viscosity is a fundamental physical parameter that indicates the functioning of cells. In this work, we developed a simple boron-dipyrromethene (BODIPY-based probe, BTV, for cellular mitochondria viscosity imaging by coupling a simple BODIPY rotor with a mitochondria-targeting unit. The BTV exhibited a significant fluorescence intensity enhancement of more than 100-fold as the solvent viscosity increased. Also, the probe showed a direct linear relationship between the fluorescence lifetime and the media viscosity, which makes it possible to trace the change of the medium viscosity. Furthermore, it was demonstrated that BTV could achieve practical applicability in the monitoring of mitochondrial viscosity changes in live cells through fluorescence lifetime imaging microscopy (FLIM.

Increases in core temperature counterbalance effects of haemoconcentration on blood viscosity during prolonged exercise in the heat.

Science.gov (United States)

Buono, Michael J; Krippes, Taylor; Kolkhorst, Fred W; Williams, Alexander T; Cabrales, Pedro

2016-02-01

What is the central question of this study? The purpose of the present study was to determine the effects of exercise-induced haemoconcentration and hyperthermia on blood viscosity. What is the main finding and its importance? Exercise-induced haemoconcentration, increased plasma viscosity and increased blood aggregation, all of which increased blood viscosity, were counterbalanced by increased red blood cell (RBC) deformability (e.g. RBC membrane shear elastic modulus and elongation index) caused by the hyperthermia. Thus, blood viscosity remained unchanged following prolonged moderate-intensity exercise in the heat. Previous studies have reported that blood viscosity is significantly increased following exercise. However, these studies measured both pre- and postexercise blood viscosity at 37 °C even though core and blood temperatures would be expected to have increased during the exercise. Consequently, the effect of exercise-induced hyperthermia on mitigating change in blood viscosity may have been missed. The purpose of this study was to isolate the effects of exercise-induced haemoconcentration and hyperthermia and to determine their combined effects on blood viscosity. Nine subjects performed 2 h of moderate-intensity exercise in the heat (37 °C, 40% relative humidity), which resulted in significant increases from pre-exercise values for rectal temperature (from 37.11 ± 0.35 to 38.76 ± 0.13 °C), haemoconcentration (haematocrit increased from 43.6 ± 3.6 to 45.6 ± 3.5%) and dehydration (change in body weight = -3.6 ± 0.7%). Exercise-induced haemoconcentration significantly (P blood viscosity by 9% (from 3.97 to 4.33 cP at 300 s(-1)), whereas exercise-induced hyperthermia significantly decreased blood viscosity by 7% (from 3.97 to 3.69 cP at 300 s(-1)). When both factors were considered together, there was no overall change in blood viscosity (from 3.97 to 4.03 cP at 300 s(-1)). The effects of exercise-induced haemoconcentration, increased plasma

Reduced viscosity for flagella moving in a solution of long polymer chains

Science.gov (United States)

Zhang, Yuchen; Li, Gaojin; Ardekani, Arezoo M.

2018-02-01

The bacterial flagellum thickness is smaller than the radius of gyration of long polymer chain molecules. The flow velocity gradient over the length of polymer chains can be nonuniform and continuum models of polymeric liquids break in this limit. In this work, we use Brownian dynamics simulations to study a rotating helical flagellum in a polymer solution and overcome this limitation. As the polymer size increases, the viscosity experienced by the flagellum asymptotically reduces to the solvent viscosity. The contribution of polymer molecules to the local viscosity in a solution of long polymer chains decreases with the inverse of polymer size to the power 1/2. The difference in viscosity experienced by the bacterial cell body and flagella can predict the nonmonotonic swimming speed of bacteria in polymer solutions.

Dynamic viscosity of polymer solutions

Energy Technology Data Exchange (ETDEWEB)

Peterlin, A

1982-03-01

The dynamic viscosity investigation of solutions of long chain polymers in very viscous solvents has definitely shown the existence of the low and high frequency plateau with the gradual transition between them. In both extreme cases the extrapolation of the measured Newtonian viscosities of the plateaus to the infinite dilution yields the limiting intrinsic viscosities. Such a behavior is expected from the dynamic intrinsic viscosity of the necklace model of the linear polymer with finite internal viscosity. The plateau at low frequency shows up in any model of polymer solution. This work shows the constant dynamic intrinsic viscosity in both extreme cases is well reproducible by the necklace model with the internal viscosity acting only between the beads on the same link. 20 references.

Black swans, power laws, and dragon-kings: Earthquakes, volcanic eruptions, landslides, wildfires, floods, and SOC models

Science.gov (United States)

Sachs, M. K.; Yoder, M. R.; Turcotte, D. L.; Rundle, J. B.; Malamud, B. D.

2012-05-01

Extreme events that change global society have been characterized as black swans. The frequency-size distributions of many natural phenomena are often well approximated by power-law (fractal) distributions. An important question is whether the probability of extreme events can be estimated by extrapolating the power-law distributions. Events that exceed these extrapolations have been characterized as dragon-kings. In this paper we consider extreme events for earthquakes, volcanic eruptions, wildfires, landslides and floods. We also consider the extreme event behavior of three models that exhibit self-organized criticality (SOC): the slider-block, forest-fire, and sand-pile models. Since extrapolations using power-laws are widely used in probabilistic hazard assessment, the occurrence of dragon-king events have important practical implications.

Influence of dispersing additives and blend composition on stability of marine high-viscosity fuels

Directory of Open Access Journals (Sweden)

Т. Н. Митусова

2017-12-01

Full Text Available The article offers a definition of the stability of marine high-viscosity fuel from the point of view of the colloid-chemical concept of oil dispersed systems. The necessity and importance of the inclusion in the current regulatory requirements of this quality parameter of high-viscosity marine fuel is indicated. The objects of the research are high-viscosity marine fuels, the basic components of which are heavy oil residues: fuel oil that is the atmospheric residue of oil refining and viscosity breaking residue that is the product of light thermal cracking of fuel oil. As a thinning agent or distillate component, a light gas oil was taken from the catalytic cracking unit. The stability of the obtained samples was determined through the xylene equivalent index, which characterizes the stability of marine high-viscosity fuel to lamination during storage, transportation and operation processes. To improve performance, the resulting base compositions of high-viscosity marine fuels were modified by introducing small concentrations (0.05 % by weight of stabilizing additives based on oxyethylated amines of domestic origin and alkyl naphthalenes of foreign origin.

Power laws and self-organized criticality in theory and nature

International Nuclear Information System (INIS)

Marković, Dimitrije; Gros, Claudius

2014-01-01

Power laws and distributions with heavy tails are common features of many complex systems. Examples are the distribution of earthquake magnitudes, solar flare intensities and the sizes of neuronal avalanches. Previously, researchers surmised that a single general concept may act as an underlying generative mechanism, with the theory of self organized criticality being a weighty contender. The power-law scaling observed in the primary statistical analysis is an important, but by far not the only feature characterizing experimental data. The scaling function, the distribution of energy fluctuations, the distribution of inter-event waiting times, and other higher order spatial and temporal correlations, have seen increased consideration over the last years. Leading to realization that basic models, like the original sandpile model, are often insufficient to adequately describe the complexity of real-world systems with power-law distribution. Consequently, a substantial amount of effort has gone into developing new and extended models and, hitherto, three classes of models have emerged. The first line of models is based on a separation between the time scales of an external drive and an internal dissipation, and includes the original sandpile model and its extensions, like the dissipative earthquake model. Within this approach the steady state is close to criticality in terms of an absorbing phase transition. The second line of models is based on external drives and internal dynamics competing on similar time scales and includes the coherent noise model, which has a non-critical steady state characterized by heavy-tailed distributions. The third line of models proposes a non-critical self-organizing state, being guided by an optimization principle, such as the concept of highly optimized tolerance. We present a comparative overview regarding distinct modeling approaches together with a discussion of their potential relevance as underlying generative models for real

Power laws and self-organized criticality in theory and nature

Energy Technology Data Exchange (ETDEWEB)

Marković, Dimitrije, E-mail: markovic@cbs.mpg.de [Institute for Theoretical Physics, Goethe University Frankfurt (Germany); Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig (Germany); Biomagnetic Center, Hans Berger Clinic for Neurology, University Hospital Jena, Jena (Germany); Gros, Claudius, E-mail: gros@itp.uni-frankfurt.de [Institute for Theoretical Physics, Goethe University Frankfurt (Germany)

2014-03-01

Power laws and distributions with heavy tails are common features of many complex systems. Examples are the distribution of earthquake magnitudes, solar flare intensities and the sizes of neuronal avalanches. Previously, researchers surmised that a single general concept may act as an underlying generative mechanism, with the theory of self organized criticality being a weighty contender. The power-law scaling observed in the primary statistical analysis is an important, but by far not the only feature characterizing experimental data. The scaling function, the distribution of energy fluctuations, the distribution of inter-event waiting times, and other higher order spatial and temporal correlations, have seen increased consideration over the last years. Leading to realization that basic models, like the original sandpile model, are often insufficient to adequately describe the complexity of real-world systems with power-law distribution. Consequently, a substantial amount of effort has gone into developing new and extended models and, hitherto, three classes of models have emerged. The first line of models is based on a separation between the time scales of an external drive and an internal dissipation, and includes the original sandpile model and its extensions, like the dissipative earthquake model. Within this approach the steady state is close to criticality in terms of an absorbing phase transition. The second line of models is based on external drives and internal dynamics competing on similar time scales and includes the coherent noise model, which has a non-critical steady state characterized by heavy-tailed distributions. The third line of models proposes a non-critical self-organizing state, being guided by an optimization principle, such as the concept of highly optimized tolerance. We present a comparative overview regarding distinct modeling approaches together with a discussion of their potential relevance as underlying generative models for real

Quantum dots with indirect band gap: power-law photoluminescence decay

Czech Academy of Sciences Publication Activity Database

Král, Karel; Menšík, Miroslav

2014-01-01

Roč. 11, č. 5 (2014), s. 507-512 ISSN 1708-5284 R&D Projects: GA MŠk LH12236; GA MŠk LH12186 Institutional support: RVO:68378271 ; RVO:61389013 Keywords : photoluminescence * quantum dots * electron-phonon interaction * inter-valley deformation potential interaction * power-law decay Subject RIV: BM - Solid Matter Physics ; Magnetism

High viscosity fluid simulation using particle-based method

KAUST Repository

Chang, Yuanzhang

2011-03-01

We present a new particle-based method for high viscosity fluid simulation. In the method, a new elastic stress term, which is derived from a modified form of the Hooke\\'s law, is included in the traditional Navier-Stokes equation to simulate the movements of the high viscosity fluids. Benefiting from the Lagrangian nature of Smoothed Particle Hydrodynamics method, large flow deformation can be well handled easily and naturally. In addition, in order to eliminate the particle deficiency problem near the boundary, ghost particles are employed to enforce the solid boundary condition. Compared with Finite Element Methods with complicated and time-consuming remeshing operations, our method is much more straightforward to implement. Moreover, our method doesn\\'t need to store and compare to an initial rest state. The experimental results show that the proposed method is effective and efficient to handle the movements of highly viscous flows, and a large variety of different kinds of fluid behaviors can be well simulated by adjusting just one parameter. © 2011 IEEE.

Kinetic Theory Derivation of the Adiabatic Law for Ideal Gases.

Science.gov (United States)

Sobel, Michael I.

1980-01-01

Discusses how the adiabatic law for ideal gases can be derived from the assumption of a Maxwell-Boltzmann (or any other) distribution of velocities--in contrast to the usual derivations from thermodynamics alone, and the higher-order effect that leads to one-body viscosity. An elementary derivation of the adiabatic law is given. (Author/DS)

An explanation for the universal 3.5 power-law observed in currency markets

Directory of Open Access Journals (Sweden)

Nicholas A. Johnson

Full Text Available We present a mathematical theory to explain a recent empirical finding in the Physics literature (Zhao et al., 2013 in which the distributions of waiting-times between discrete events were found to exhibit power-law tails with an apparent universal exponent: α∼3.5. This new theory provides the first ever qualitative and quantitative explanation of Zhao et al.’s surprising finding. It also provides a mechanistic description of the origin of the observed universality, assigning its cause to the emergence of dynamical feedback processes between evolving clusters of like-minded agents. Keywords: Complex systems, Econophysics, Collective, Power law

Microfluidics for simultaneous quantification of platelet adhesion and blood viscosity

Science.gov (United States)

Yeom, Eunseop; Park, Jun Hong; Kang, Yang Jun; Lee, Sang Joon

2016-01-01

Platelet functions, including adhesion, activation, and aggregation have an influence on thrombosis and the progression of atherosclerosis. In the present study, a new microfluidic-based method is proposed to estimate platelet adhesion and blood viscosity simultaneously. Blood sample flows into an H-shaped microfluidic device with a peristaltic pump. Since platelet aggregation may be initiated by the compression of rotors inside the peristaltic pump, platelet aggregates may adhere to the H-shaped channel. Through correlation mapping, which visualizes decorrelation of the streaming blood flow, the area of adhered platelets (APlatelet) can be estimated without labeling platelets. The platelet function is estimated by determining the representative index IA·T based on APlatelet and contact time. Blood viscosity is measured by monitoring the flow conditions in the one side channel of the H-shaped device. Based on the relation between interfacial width (W) and pressure ratio of sample flows to the reference, blood sample viscosity (μ) can be estimated by measuring W. Biophysical parameters (IA·T, μ) are compared for normal and diabetic rats using an ex vivo extracorporeal model. This microfluidic-based method can be used for evaluating variations in the platelet adhesion and blood viscosity of animal models with cardiovascular diseases under ex vivo conditions. PMID:27118101

Effect of temperature and viscosity on swimming velocity of the copepod Acartia tonsa, brine shrimp Artemia salina and rotifer Brachionus plicatilis

DEFF Research Database (Denmark)

Larsen, Poul Scheel; Madsen, C.V.; Riisgard, H.U.

2008-01-01

Beating cilia are important organelles for swimming in many zooplanktonic aquatic organisms, including many invertebrate larvae, rotifers and ciliates, but other planktonic organisms, such as copepods and brine shrimps, use muscle-powered swimming appendages. In recent studies we found...... of swimming velocity for a 10 degrees C temperature reduction) that is found to be largest for the brine shrimp Artemia salina nauplius (37 %) and the rotifer Brachionus plicatilis (26%), but negligible for the copepod Acartia tonsa (4%). We suggest that experimental data on change in swimming velocity (V......) due to change in kinematic viscosity (v) be correlated in terms of a power law, V proportional to v(-m). The present data on swimming velocity of copepods, brine shrimps and rotifers show values of exponent m approximate to 1.5 to 3, with a trend of decreasing values for increasing size of species...

The end of nuclear power? The conflict of politics, ecology and law

International Nuclear Information System (INIS)

Strassburg, W.

1999-01-01

The German federal government's demand to opt out of the peaceful use of nuclear power is examined under aspects of constitutional law. Constitutional barriers allow the peaceful use of nuclear power to be discontinued without any compensation only in the distant future. A general restriction of the useful life of plants does not constitute a modification of ownership rights but deprivation, i.e., expropriation. In this politically desired opt-out, the government also must bear in mind that the constitution protects not only the property but also the freedom to exercise their profession (Article 12, para. 1, German Basic Law) of all those who have been committed to this industry for decades. Also a national ban on reprocessing with transborder effects violates existing law, counteracting the requirement of a free exchange of goods and services within the single European market. Moreover, the existing reprocessing contracts with foreign companies may be terminated unilaterally only subject to indemnification, as they constitute obligations under international law, unless German customers were to exercise their contractual right to cancel. In addition, it is to be feared that discontinuation of the peaceful uses of nuclear power manifests itself in the absence of provisions for the back end of the fuel cycle. Prolonging the exploration of repositories and, consequently, relying more and more heavily on interim stores, is bound to raise the question of the evidence of spent fuel and waste management in these latter facilities. In the absence of sufficient proof of waste management provisions in interim stores, the accusation could be leveled that it was not certain whether these interim stores were not turning into final stores. (orig.) [de

Universal correlations and power-law tails in financial covariance matrices

Science.gov (United States)

Akemann, G.; Fischmann, J.; Vivo, P.

2010-07-01

We investigate whether quantities such as the global spectral density or individual eigenvalues of financial covariance matrices can be best modelled by standard random matrix theory or rather by its generalisations displaying power-law tails. In order to generate individual eigenvalue distributions a chopping procedure is devised, which produces a statistical ensemble of asset-price covariances from a single instance of financial data sets. Local results for the smallest eigenvalue and individual spacings are very stable upon reshuffling the time windows and assets. They are in good agreement with the universal Tracy-Widom distribution and Wigner surmise, respectively. This suggests a strong degree of robustness especially in the low-lying sector of the spectra, most relevant for portfolio selections. Conversely, the global spectral density of a single covariance matrix as well as the average over all unfolded nearest-neighbour spacing distributions deviate from standard Gaussian random matrix predictions. The data are in fair agreement with a recently introduced generalised random matrix model, with correlations showing a power-law decay.

German atomic energy law in the international framework

International Nuclear Information System (INIS)

Pelzer, N.

1992-01-01

The regional conference was devoted to the legal problems that ensue from German reunification against the background of the integration of German atomic energy law within international law. The elements of national atomic energy legislation required by international law and recent developments in international nuclear liability law were discussed from different perspectives. The particular problems of the application of the German Atomic Energy Act in the 5 new Laender (the territories of the former GDR) were presented and discussed, namely: The continued validity of old licences issued by the GDR; practical legal problems connected with the construction of nuclear power plants in the 5 new Laender; the legal issues connected with the final repository for radioactive wastes at Morsleben; and the new developments in radiation protection law following from the Unification Treaty and the new ICRP recommendations. All 14 lectures have been abstracted and indexed individually. (orig.) [de

Power-law index and penetration depth of (Nd_xSm_xGd_1−2x)Ba2Cu₃O_7−δ films studied by AC susceptibility

DEFF Research Database (Denmark)

Li, Xiaofen; He, Dong; Grivel, Jean-Claude

2012-01-01

Superconducting (NdxSmxGd1−2x)Ba2Cu3O7−δ films with x=0, 0.1, 0.25, 0.33 were grown by PLD on STO single crystal substrates. The power-law index n and penetration depth λ are studied by AC susceptibility. During cooling, n in films with x ≠ 0 increases much slower compared with the films with x =....... The films with x ≠ 0 also tend to have a longer penetration depth. These properties might be related to the higher possibility for disorder in the mixed (Nd,Sm,Gd)BCO films....

Dust-acoustic waves and stability in the permeating dusty plasma. II. Power-law distributions

International Nuclear Information System (INIS)

Gong Jingyu; Du Jiulin; Liu Zhipeng

2012-01-01

The dust-acoustic waves and the stability theory for the permeating dusty plasma with power-law distributions are studied by using nonextensive q-statistics. In two limiting physical cases, when the thermal velocity of the flowing dusty plasma is much larger than, and much smaller than the phase velocity of the waves, we derived the dust-acoustic wave frequency, the instability growth rate, and the instability critical flowing velocity. As compared with the formulae obtained in part I [Gong et al., Phys. Plasmas 19, 043704 (2012)], all formulae of the present cases and the resulting plasma characteristics are q-dependent, and the power-law distribution of each plasma component of the permeating dusty plasma has a different q-parameter and thus has a different nonextensive effect. Further, we make numerical analyses of an example that a cometary plasma tail is passing through the interplanetary space dusty plasma and we show that these power-law distributions have significant effects on the plasma characteristics of this kind of plasma environment.

The Inverse System Method Applied to the Derivation of Power System Non—linear Control Laws

Institute of Scientific and Technical Information of China (English)

DonghaiLI; XuezhiJIANG; 等

1997-01-01

The differential geometric method has been applied to a series of power system non-linear control problems effectively.However a set of differential equations must be solved for obtaining the required diffeomorphic transformation.Therefore the derivation of control laws is very complicated.In fact because of the specificity of power system models the required diffeomorphic transformation may be obtained directly,so it is unnecessary to solve a set of differential equations.In addition inverse system method is equivalent to differential geometric method in reality and not limited to affine nonlinear systems,Its physical meaning is able to be viewed directly and its deduction needs only algebraic operation and derivation,so control laws can be obtained easily and the application to engineering is very convenient.Authors of this paper take steam valving control of power system as a typical case to be studied.It is demonstrated that the control law deduced by inverse system method is just the same as one by differential geometric method.The conclusion will simplify the control law derivations of steam valving,excitation,converter and static var compensator by differential geometric method and may be suited to similar control problems in other areas.

The Causal Connection Between Disc and Power-Law Variability in Hard State Black Hole X-Ray Binaries

Science.gov (United States)

Uttley, P.; Wilkinson, T.; Cassatella, P.; Wilms, J.; Pottschimdt, K.; Hanke, M.; Boeck, M.

2010-01-01

We use the XMM-Newton EPIC-pn instrument in timing mode to extend spectral time-lag studies of hard state black hole X-ray binaries into the soft X-ray band. \\Ve show that variations of the disc blackbody emission substantially lead variations in the power-law emission, by tenths of a second on variability time-scales of seconds or longer. The large lags cannot be explained by Compton scattering but are consistent with time-delays due to viscous propagation of mass accretion fluctuations in the disc. However, on time-scales less than a second the disc lags the power-law variations by a few ms, consistent with the disc variations being dominated by X-ray heating by the power-law, with the short lag corresponding to the light-travel time between the power-law emitting region and the disc. Our results indicate that instabilities in the accretion disc are responsible for continuum variability on time-scales of seconds or longer and probably also on shorter time-scales.

Theories of Power, Poverty, and Law: In Commemoration of the Contributions of Peter Bachrach--Power, Law, and Final Thoughts: The Contributions of Peter Bachrach

Science.gov (United States)

Schneider, Elizabeth M.

2010-01-01

I am pleased to be part of this symposium to celebrate the life and work of Peter Bachrach. Although my focus is the relevance of Peter's ideas of power to law, I want to begin with some personal comments as well as raise some final thoughts, drawing on others' contributions. Like so many of Peter's other students, I adored him. Peter's joy in…

Power law of distribution of emergency situations on main gas pipeline

Science.gov (United States)

Voronin, K. S.; Akulov, K. A.

2018-05-01

The article presents the results of the analysis of emergency situations on a main gas pipeline. A power law of distribution of emergency situations is revealed. The possibility of conducting further scientific research to ensure the predictability of emergency situations on pipelines is justified.

Active Power Filter DC Bus Voltage Piecewise Reaching Law Variable Structure Control

OpenAIRE

Liu, Baolian; Ding, Zujun; Zhao, Huanyu; Jin, Defei

2014-01-01

The DC bus voltage stability control is one key technology to ensure that Active Power Filter (APF) operates stably. The external disturbances such as power grid and load fluctuation and the system parameters changing may affect the stability of APF DC bus voltage and the normal operation of APF. The mathematical model of DC bus voltage is established according to power balance principle and a DC bus voltage piecewise reaching law variable structure control algorithm is proposed to solve the ...

SUBJECT INDEX

Indian Academy of Sciences (India)

Unknown

Activation energy of viscous flow. Density and viscosity of magnesium sulphate formamide + ethylene glycol mixed solvents ... high average power TEA CO2 laser. 659. Carpaine ... organic sulphides 2,2′-bipyridinium chlo- rochromate. 137.

Band head spin assignment of superdeformed bands in Hg isotopes through power index formula

Science.gov (United States)

Sharma, Honey; Mittal, H. M.

2018-05-01

The power index formula has been used to obtain the band head spin (I 0) of all the superdeformed (SD) bands in Hg isotopes. A least squares fitting approach is used. The root mean square deviations between the determined and the observed transition energies are calculated by extracting the model parameters using the power index formula. Whenever definite spins are available, the determined and the observed transition energies are in accordance with each other. The computed values of dynamic moment of inertia J (2) obtained by using the power index formula and its deviation with the rotational frequency is also studied. Excellent agreement is shown between the calculated and the experimental results for J (2) versus the rotational frequency. Hence, the power index formula works very well for all the SD bands in Hg isotopes expect for 195Hg(2, 3, 4).

The use of energy analysis and indexes of energy efficiency in nuclear power

International Nuclear Information System (INIS)

D'yakonov, E.I.; Ignatenko, E.I.

1991-01-01

The results of calculating the indexes of energy efficiency for NPPs with the WWER-1000 and RBMK-1000 reactors, heat and power NPPs with the WWER-1000 and dictrict heating NPPs with the AST-500 reactor in three fuel cycles, namely, the open one and with uranium and plutonium recycles, are considered. Complex account for the quantity and quality of produced and consumed energy provides for objective evaluation of the indexes of energy efficiency during comparative analysis of nuclear power plants with different types of reactors. It is shown that complex use of the energy produced at a NPP provides for increase of indexes of energy efficiency. The highest indexes are obtained for heat and power NPP with the WWER-1000 reactor in the open fuel cycle, with uranium and plutonium recycle and for NPP with the WWER-1000 reactor with plutonium recycle

Tornado outbreak variability follows Taylor's power law of fluctuation scaling and increases dramatically with severity.

Science.gov (United States)

Tippett, Michael K; Cohen, Joel E

2016-02-29

Tornadoes cause loss of life and damage to property each year in the United States and around the world. The largest impacts come from 'outbreaks' consisting of multiple tornadoes closely spaced in time. Here we find an upward trend in the annual mean number of tornadoes per US tornado outbreak for the period 1954-2014. Moreover, the variance of this quantity is increasing more than four times as fast as the mean. The mean and variance of the number of tornadoes per outbreak vary according to Taylor's power law of fluctuation scaling (TL), with parameters that are consistent with multiplicative growth. Tornado-related atmospheric proxies show similar power-law scaling and multiplicative growth. Path-length-integrated tornado outbreak intensity also follows TL, but with parameters consistent with sampling variability. The observed TL power-law scaling of outbreak severity means that extreme outbreaks are more frequent than would be expected if mean and variance were independent or linearly related.

Tornado outbreak variability follows Taylor's power law of fluctuation scaling and increases dramatically with severity

Science.gov (United States)

Tippett, Michael K.; Cohen, Joel E.

2016-01-01

Tornadoes cause loss of life and damage to property each year in the United States and around the world. The largest impacts come from ‘outbreaks' consisting of multiple tornadoes closely spaced in time. Here we find an upward trend in the annual mean number of tornadoes per US tornado outbreak for the period 1954–2014. Moreover, the variance of this quantity is increasing more than four times as fast as the mean. The mean and variance of the number of tornadoes per outbreak vary according to Taylor's power law of fluctuation scaling (TL), with parameters that are consistent with multiplicative growth. Tornado-related atmospheric proxies show similar power-law scaling and multiplicative growth. Path-length-integrated tornado outbreak intensity also follows TL, but with parameters consistent with sampling variability. The observed TL power-law scaling of outbreak severity means that extreme outbreaks are more frequent than would be expected if mean and variance were independent or linearly related. PMID:26923210

A non-coulombic effective power-law potential for the heavy quarkoniums

International Nuclear Information System (INIS)

Barik, N.; Jena, S.N.

1980-01-01

An effective power-law potential of the form V(r) = 6.08 r 0 sup(.) 106 - 6.41 is found to describe satisfactorily the gross features of the mass spectra and the leptonic width ratios of the cc and bb systems in a flavour-independent manner. (orig.)

Breaking the power law: Multiscale simulations of self-ion irradiated tungsten

Science.gov (United States)

Jin, Miaomiao; Permann, Cody; Short, Michael P.

2018-06-01

The initial stage of radiation defect creation has often been shown to follow a power law distribution at short time scales, recently so with tungsten, following many self-organizing patterns found in nature. The evolution of this damage, however, is dominated by interactions between defect clusters, as the coalescence of smaller defects into clusters depends on the balance between transport, absorption, and emission to/from existing clusters. The long-time evolution of radiation-induced defects in tungsten is studied with cluster dynamics parameterized with lower length scale simulations, and is shown to deviate from a power law size distribution. The effects of parameters such as dose rate and total dose, as parameters affecting the strength of the driving force for defect evolution, are also analyzed. Excellent agreement is achieved with regards to an experimentally measured defect size distribution at 30 K. This study provides another satisfactory explanation for experimental observations in addition to that of primary radiation damage, which should be reconciled with additional validation data.

Power-law photoluminescence decay in indirect gap quantum dots

Czech Academy of Sciences Publication Activity Database

Menšík, Miroslav; Král, Karel

2013-01-01

Roč. 111, November (2013), s. 170-174 ISSN 0167-9317 R&D Projects: GA MŠk(CZ) OC10007; GA MŠk LH12186; GA MŠk LH12236; GA ČR(CZ) GAP205/10/2280 Institutional support: RVO:61389013 ; RVO:68378271 Keywords : quantum dots * indirect gap transition * power-law photoluminescence decay Subject RIV: BM - Solid Matter Physics ; Magnetism; BE - Theoretical Physics (FZU-D) Impact factor: 1.338, year: 2013

The Nucleolus as a Consistent Power Index in Noncooerative Majority Games

NARCIS (Netherlands)

Montero, M.P.

2001-01-01

This paper studies noncooperative bargaining with random proposers in proper single games. A power index is called consistent if it can be obtained as an equilibrium of the game with random proposers using the index itself as probability vector. Unlike the Shapley-Shubik and Banzhaf indices, the

Practical experience with second law power plant monitoring

International Nuclear Information System (INIS)

Lang, F.D.; Horn, K.F.

1992-01-01

This article discusses the use of an ultimate performance monitoring technique derived from Second Law concepts. Other techniques and their methods have been reported. If electricity is to be produced with the minimum of unproductive consumption of fuel - then fundamental thermodynamic losses must be understood on a system bases. Such understanding cuts across vendor curves, plant design, fuels, etc. Thermal losses in a nuclear unit are comparable at a prime facia level to losses at any other thermal system. They are what we must minimize in the production of electricity, no manner the method of that production. The Second Law offers the only foundation for the study of such losses, and thus affords the bases for a true and ultimate indicator of system performance. From such a foundation, a parameter is needed to tell us specifically what components are thermodynamically responsible for fuel consumption given either their direct creation of electricity or their contribution to thermodynamic losses. The Fuel Consumption Index, discussed in this article, is this parameter. It can be used for thermodynamic system design, monitoring, diagnosing problems, and economic dispatching. It tells us why fuel is being consumed; consumed by a nuclear plant, trash burner, a 40 year-old fossil plant, etc

High Resolution Viscosity Measurement by Thermal Noise Detection

Directory of Open Access Journals (Sweden)

Felipe Aguilar Sandoval

2015-11-01

Full Text Available An interferometric method is implemented in order to accurately assess the thermal fluctuations of a micro-cantilever sensor in liquid environments. The power spectrum density (PSD of thermal fluctuations together with Sader’s model of the cantilever allow for the indirect measurement of the liquid viscosity with good accuracy. The good quality of the deflection signal and the characteristic low noise of the instrument allow for the detection and corrections of drawbacks due to both the cantilever shape irregularities and the uncertainties on the position of the laser spot at the fluctuating end of the cantilever. Variation of viscosity below 0.03 mPa·s was detected with the alternative to achieve measurements with a volume as low as 50 µL.

Foaming Index of CaO-SiO2-FeO-MgO Slag System

Science.gov (United States)

Park, Youngjoo; Min, Dong Joon

A study on the effect of FeO and MgO content on foaming index in EAF slag system was carried out. The height of the slag foam was measured by electric probe maintaining steady state in gas formation and escape. Foaming index, which is the measurement of gas capturing potential of the slag, is calculated from the foam height and gas flow rate. Viscosity and surface tension, which are the key properties for the foaming index, are calculated by Urbain's model and additive method, respectively. Dimensional analysis also performed to determine the dominancy of properties and resulted that the important factor was a ratio between viscosity and surface tension. The effect of each component on the viscosity, surface tension and foaming index of the slag is evaluated to be in strong relationship.

Experimental evaluation of the MIT-SNL period-generated minimum time control laws for the rapid adjustment of reactor power

International Nuclear Information System (INIS)

Bernard, J.A.; Kwok, K.S.; Menadier, P.T.; Thome, F.V.; Wyant, F.J.

1987-01-01

The rapid adjustment of reactor neutronic power has recently been achieved by developing control laws that determine the actuator mechanism velocity necessary to produce a specified reactor period. Designated as the 'MIT-SNL Period-Generated Minimum Time Control Laws,' these relations are closed-form expressions of general applicability. In particular, if there is no limitation on the available rate of change of reactivity, these laws can be used to achieve virtually any desired power profile including time optimal ones. The innovative aspect of these laws is that the rate of change of reactivity rather than the reactivity itself is used as the control signal. For example, relative to a time-optimal response, these laws function by altering the rate of change of reactivity so that the instantaneous period is stepped from infinity to its minimum allowed value, held at that value until the desired power level is attained, and then stepped back to infinity. The response is time-optimal because the power adjustment is continuously made at the maximum allowed rate

Index: Mizan Law Review (Vol. 1 to 10)

African Journals Online (AJOL)

eliasn

Environmental Law. Evidence .... Protection of the Environment and the. International ..... Counter-intervention, Invitation, Both or. Neither: An ... Prioritizing Water Use Rights in Ethiopia: ... Notes on Jurisprudence: Natural Law (169-. 178).

Modeling the Multiband Afterglows of GRB 060614 and GRB 060908: Further Evidence for a Double Power-law Hard Electron Energy Spectrum

Science.gov (United States)

Zhang, Q.; Xiong, S. L.; Song, L. M.

2018-04-01

Electrons accelerated in relativistic collisionless shocks are usually assumed to follow a power-law energy distribution with an index of p. Observationally, although most gamma-ray bursts (GRBs) have afterglows that are consistent with p > 2, there are still a few GRBs suggestive of a hard (p law hard electron energy (DPLH) spectrum with 1 2 and an “injection break” assumed as γ b ∝ γ q in the highly relativistic regime, where γ is the bulk Lorentz factor of the jet. In this paper, we show that GRB 060614 and GRB 060908 provide further evidence for such a DPLH spectrum. We interpret the multiband afterglow of GRB 060614 with the DPLH model in a homogeneous interstellar medium by taking into account a continuous energy injection process, while, for GRB 060908, a wind-like circumburst density profile is used. The two bursts, along with GRB 091127, suggest a similar behavior in the evolution of the injection break, with q ∼ 0.5. Whether this represents a universal law of the injection break remains uncertain and more afterglow observations such as these are needed to test this conjecture.

Power-law Growth and Punctuated Equilibrium Dynamics in Water Resources Systems

Science.gov (United States)

Parolari, A.; Katul, G. G.; Porporato, A. M.

2015-12-01

The global rise in population-driven water scarcity and recent appreciation of strong dynamic coupling between human and natural systems has called for new approaches to predict the future sustainability of regional and global water resources systems. The dynamics of coupled human-water systems are driven by a complex set of social, environmental, and technological factors. Present projections of water resources systems range from a finite carrying capacity regulated by accessible freshwater, or `peak renewable water,' to punctuated evolution with new supplied and improved efficiency gained from technological and social innovation. However, these projections have yet to be quantified from observations or in a comprehensive theoretical framework. Using data on global water withdrawals and storage capacity of regional water supply systems, non-trivial dynamics are identified in water resources systems development over time, including power-law growth and punctuated equilibria. Two models are introduced to explain this behavior: (1) a delay differential equation and (2) a power-law with log-periodic oscillations, both of which rely on past conditions (or system memory) to describe the present rate of growth in the system. In addition, extension of the first model demonstrates how system delays and punctuated equilibria can emerge from coupling between human population growth and associated resource demands. Lastly, anecdotal evidence is used to demonstrate the likelihood of power-law growth in global water use from the agricultural revolution 3000 BC to the present. In a practical sense, the presence of these patterns in models with delayed oscillations suggests that current decision-making related to water resources development results from the historical accumulation of resource use decisions, technological and social changes, and their consequences.

The shape of the primordial power spectrum: A last stand before Planck data

International Nuclear Information System (INIS)

Peiris, Hiranya V.; Verde, Licia

2010-01-01

We present a minimally parametric reconstruction of the primordial power spectrum using the most recent cosmic microwave background and large-scale structure data sets. Our goal is to constrain the shape of the power spectrum while simultaneously avoiding strong theoretical priors and over-fitting of the data. We find no evidence for any departure from a power-law spectral index. We also find that an exact scale-invariant power spectrum is disfavored by the data, but this conclusion is weaker than the corresponding result assuming a theoretically-motivated power-law spectral index prior. The reconstruction shows that better data are crucial to justify the adoption of such a strong theoretical prior observationally. These results can be used to determine the robustness of our present knowledge when compared with forthcoming precision data from Planck.

Shear viscosity and imperfect fluidity in bosonic and fermionic superfluids

Science.gov (United States)

Boyack, Rufus; Guo, Hao; Levin, K.

2014-12-01

In this paper we address the ratio of the shear viscosity to entropy density η /s in bosonic and fermionic superfluids. A small η /s is associated with nearly perfect fluidity, and more general measures of the fluidity perfection/imperfection are of wide interest to a number of communities. We use a Kubo approach to concretely address this ratio via low-temperature transport associated with the quasiparticles. Our analysis for bosonic superfluids utilizes the framework of the one-loop Bogoliubov approximation, whereas for fermionic superfluids we apply BCS theory and its BCS-BEC extension. Interestingly, we find that the transport properties of strict BCS and Bogoliubov superfluids have very similar structures, albeit with different quasiparticle dispersion relations. While there is a dramatic contrast between the power law and exponential temperature dependence for η alone, the ratio η /s for both systems is more similar. Specifically, we find the same linear dependence (on the ratio of temperature T to inverse lifetime γ (T ) ) with η /s ∝T /γ (T ) , corresponding to imperfect fluidity. By contrast, near the unitary limit of BCS-BEC superfluids a very different behavior results, which is more consistent with near-perfect fluidity.

Nuclear power performance and safety. V.6.: Indexes and lists

International Nuclear Information System (INIS)

1988-01-01

The sixth volume of the proceedings of the international conference on nuclear power performance and safety organized by the IAEA and held in Vienna between 28 September and 2 October 1987 presents the contents of volumes 1-5, the list of Chairmen of Sessions and the Secretariat of the Conference, the list of participants, the author and transliteration indexes, the index of papers and posters by number

Inference of viscosity jump at 670 km depth and lower mantle viscosity structure from GIA observations

Science.gov (United States)

Nakada, Masao; Okuno, Jun'ichi; Irie, Yoshiya

2018-03-01

A viscosity model with an exponential profile described by temperature (T) and pressure (P) distributions and constant activation energy (E_{{{um}}}^{{*}} for the upper mantle and E_{{{lm}}}^* for the lower mantle) and volume (V_{{{um}}}^{{*}} and V_{{{lm}}}^*) is employed in inferring the viscosity structure of the Earth's mantle from observations of glacial isostatic adjustment (GIA). We first construct standard viscosity models with an average upper-mantle viscosity ({\\bar{η }_{{{um}}}}) of 2 × 1020 Pa s, a typical value for the oceanic upper-mantle viscosity, satisfying the observationally derived three GIA-related observables, GIA-induced rate of change of the degree-two zonal harmonic of the geopotential, {\\dot{J}_2}, and differential relative sea level (RSL) changes for the Last Glacial Maximum sea levels at Barbados and Bonaparte Gulf in Australia and for RSL changes at 6 kyr BP for Karumba and Halifax Bay in Australia. Standard viscosity models inferred from three GIA-related observables are characterized by a viscosity of ˜1023 Pa s in the deep mantle for an assumed viscosity at 670 km depth, ηlm(670), of (1 - 50) × 1021 Pa s. Postglacial RSL changes at Southport, Bermuda and Everglades in the intermediate region of the North American ice sheet, largely dependent on its gross melting history, have a crucial potential for inference of a viscosity jump at 670 km depth. The analyses of these RSL changes based on the viscosity models with {\\bar{η }_{{{um}}}} ≥ 2 × 1020 Pa s and lower-mantle viscosity structures for the standard models yield permissible {\\bar{η }_{{{um}}}} and ηlm (670) values, although there is a trade-off between the viscosity and ice history models. Our preferred {\\bar{η }_{{{um}}}} and ηlm (670) values are ˜(7 - 9) × 1020 and ˜1022 Pa s, respectively, and the {\\bar{η }_{{{um}}}} is higher than that for the typical value of oceanic upper mantle, which may reflect a moderate laterally heterogeneous upper

An objective decision model of power grid environmental protection based on environmental influence index and energy-saving and emission-reducing index

Science.gov (United States)

Feng, Jun-shu; Jin, Yan-ming; Hao, Wei-hua

2017-01-01

Based on modelling the environmental influence index of power transmission and transformation project and energy-saving and emission-reducing index of source-grid-load of power system, this paper establishes an objective decision model of power grid environmental protection, with constraints of power grid environmental protection objectives being legal and economical, and considering both positive and negative influences of grid on the environmental in all-life grid cycle. This model can be used to guide the programming work of power grid environmental protection. A numerical simulation of Jiangsu province’s power grid environmental protection objective decision model has been operated, and the results shows that the maximum goal of energy-saving and emission-reducing benefits would be reached firstly as investment increasing, and then the minimum goal of environmental influence.

Modeling the complexity of acoustic emission during intermittent plastic deformation: Power laws and multifractal spectra.

Science.gov (United States)

Kumar, Jagadish; Ananthakrishna, G

2018-01-01

Scale-invariant power-law distributions for acoustic emission signals are ubiquitous in several plastically deforming materials. However, power-law distributions for acoustic emission energies are reported in distinctly different plastically deforming situations such as hcp and fcc single and polycrystalline samples exhibiting smooth stress-strain curves and in dilute metallic alloys exhibiting discontinuous flow. This is surprising since the underlying dislocation mechanisms in these two types of deformations are very different. So far, there have been no models that predict the power-law statistics for discontinuous flow. Furthermore, the statistics of the acoustic emission signals in jerky flow is even more complex, requiring multifractal measures for a proper characterization. There has been no model that explains the complex statistics either. Here we address the problem of statistical characterization of the acoustic emission signals associated with the three types of the Portevin-Le Chatelier bands. Following our recently proposed general framework for calculating acoustic emission, we set up a wave equation for the elastic degrees of freedom with a plastic strain rate as a source term. The energy dissipated during acoustic emission is represented by the Rayleigh-dissipation function. Using the plastic strain rate obtained from the Ananthakrishna model for the Portevin-Le Chatelier effect, we compute the acoustic emission signals associated with the three Portevin-Le Chatelier bands and the Lüders-like band. The so-calculated acoustic emission signals are used for further statistical characterization. Our results show that the model predicts power-law statistics for all the acoustic emission signals associated with the three types of Portevin-Le Chatelier bands with the exponent values increasing with increasing strain rate. The calculated multifractal spectra corresponding to the acoustic emission signals associated with the three band types have a maximum

Numerical simulation of heat transfer in power law fluid flow through a stenosed artery

Science.gov (United States)

Talib, Amira Husni; Abdullah, Ilyani

2017-11-01

A numerical study of heat transfer in a power law fluid is investigated in this paper. The blood flow is treated as power law fluid with a presence of cosine shaped stenosis. This study reveals the effect of stenosis on the heat transfer and velocity of blood flowing in the constricted artery. The governing and energy equations are formulated in a cylindrical coordinate system. Hence, the set of equations and boundary conditions are solved numerically by Marker and Cell (MAC) method. The graphical result shows the profile of blood temperature is increased while the blood velocity is decreased at the critical height of stenosis.

Dewetting of low-viscosity films at solid/liquid interfaces.

Science.gov (United States)

Péron, Nicolas; Brochard-Wyart, Françoise; Duval, Hervé

2012-11-13

We report new experimental results on the dewetting of a mercury film (A) intercalated between a glass slab and an external nonmiscible liquid phase (B) under conditions of a large equilibrium contact angle. The viscosity of the external phase, ηB, was varied over 7 orders of magnitude. We observe a transition between two regimes of dewetting at a threshold viscosity of η(B)* ≈ (ρ(A)e|S̃|)(1/2), where ρ(A) is the mercury density, e is the film thickness, and |S̃| is the effective spreading coefficient. For η(B) dewetting is constant and ruled by Culick’s law, V ≈ (|S̃|/(ρ(A)e))(1/2). Capillary waves were observed at high dewetting velocities: they are a signature of hydraulic shock. For η(B) > η(B)*, the regime is viscous. The dewetting velocity is constant and scales as V ≈ |S̃|/η(B) in the limit of large η(B). We interpret this regime by a balance between the surface energy released during dewetting and the viscous dissipation in the surrounding liquid.

Second Law Analysis for a Variable Viscosity Reactive Couette Flow under Arrhenius Kinetics

Directory of Open Access Journals (Sweden)

N. S. Kobo

2010-01-01

Full Text Available This study investigates the inherent irreversibility associated with the Couette flow of a reacting variable viscosity combustible material under Arrhenius kinetics. The nonlinear equations of momentum and energy governing the flow system are solved both analytically using a perturbation method and numerically using the standard Newton Raphson shooting method along with a fourth-order Runge Kutta integration algorithm to obtain the velocity and temperature distributions which essentially expedite to obtain expressions for volumetric entropy generation numbers, irreversibility distribution ratio, and the Bejan number in the flow field.

Powerful subjects of tax law enforcement

Directory of Open Access Journals (Sweden)

Igor Dementyev

2017-01-01

Full Text Available УДК 342.6The subject. Competence of government bodies and their officials in the sphere of application of the tax law is considered in the article.The purpose of research is to determine the ratio of tax enforcement and application of the tax law, as well as the relationship between the concepts “party of tax enforcement” and “participant of tax legal relations”.Main results and scope of their application. The circle of participants of tax legal relations is broader than the circle of parties of tax law enforcement. The participants of tax legal relations are simultaneously the subjects of tax law, because they realize their tax status when enter into the tax relationships. The tax and customs authorities are the undoubted parties of the tax law enforcement.Although the financial authorities at all levels of government are not mentioned by article 9 of the Tax Code of the Russian Federation as participants of tax relations, they are parties of tax enforcement, because they make the agreement for deferment or installment payment of regional and local taxes.Scope of application. Clarification of participants of tax legal relations and determination of their mutual responsibility is essential to effective law enforcement.Conclusion. It was concluded that the scope tax law enforcement is tax proceedings, not administrative proceedings, civil (arbitration proceedings or enforcement proceedings.The application of the tax law is carried out not only in the form of tax relations, but also in relations of other branches of law.

Power Law Distributions in Two Community Currencies

Science.gov (United States)

Kichiji, N.; Nishibe, M.

2007-07-01

The purpose of this paper is to highlight certain newly discovered social phenomena that accord with Zipf's law, in addition to the famous natural and social phenomena including word frequencies, earthquake magnitude, city size, income1 etc. that are already known to follow it. These phenomena have recently been discovered within the transaction amount (payments or receipts) distributions within two different Community Currencies (CC) that had been initiated as social experiments. One is a local CC circulating in a specific geographical area, such as a town. The other is a virtual CC used among members who belong to a certain community of interest (COI) on the Internet. We conducted two empirical studies to estimate the economic vitalization effects they had on their respective local economies. The results we found were that the amount of transactions (payments and receipts) of the two CCs was distributed according to a power-law distribution with a unity rank exponent. In addition, we found differences between the two CCs with regard to the shapes of their distribution over a low-transaction range. The result may originate from the difference in methods of issuing CCs or in the magnitudes of the minimum-value unit; however, this result calls for further investigation.

Mathematical analysis of the global dynamics of a power law model ...

African Journals Online (AJOL)

We analyze a mathematical power law model that describes HIV infection of CD4+ T cells. We report that the number of critical points depends on , where is a positive integer. We show that for any positive integer the infection – free equilibrium is asymptotically stable if the reproduction number R0 1.

Universal power-law diet partitioning by marine fish and squid with surprising stability–diversity implications

Science.gov (United States)

Rossberg, Axel G.; Farnsworth, Keith D.; Satoh, Keisuke; Pinnegar, John K.

2011-01-01

A central question in community ecology is how the number of trophic links relates to community species richness. For simple dynamical food-web models, link density (the ratio of links to species) is bounded from above as the number of species increases; but empirical data suggest that it increases without bounds. We found a new empirical upper bound on link density in large marine communities with emphasis on fish and squid, using novel methods that avoid known sources of bias in traditional approaches. Bounds are expressed in terms of the diet-partitioning function (DPF): the average number of resources contributing more than a fraction f to a consumer's diet, as a function of f. All observed DPF follow a functional form closely related to a power law, with power-law exponents independent of species richness at the measurement accuracy. Results imply universal upper bounds on link density across the oceans. However, the inherently scale-free nature of power-law diet partitioning suggests that the DPF itself is a better defined characterization of network structure than link density. PMID:21068048

The law governing power generation and the atomic energy law in Japan, with special regard to the current situation in the energy sector

International Nuclear Information System (INIS)

Fujiwara, J.

1984-01-01

This contribution characterises Japanese legislation on power generation and supply, goes into detail with regard to the current Atomic Energy Law within the framework of the overall legal concept governing power supply, and presents an outlook on future developments. A table summarizes the main problems in this field. (orig./HSCH) [de

Densities, refractive indices, and viscosities of N,N-diethylethanol ammonium chloride–glycerol or –ethylene glycol deep eutectic solvents and their aqueous solutions

International Nuclear Information System (INIS)

Siongco, Kathrina R.; Leron, Rhoda B.; Li, Meng-Hui

2013-01-01

Highlights: • The densities, refractive indices, and viscosities of aqueous DES solutions were measured. • DES are made from N,N-diethylethanol ammonium chloride + glycerol or ethylene glycol. • The temperature studied was (298.15 to 343.15) K. • The measured data were reported as functions of temperature and composition. • The measured data were represented satisfactorily by the applied correlations. -- Abstract: In this work, we report new experimental data on density, ρ, refractive index, n D, and viscosity, η, of two deep eutectic solvents, N,N-diethylethanol ammonium chloride–glycerol (DEACG) and N,N-diethylethanol ammonium chloride–ethylene glycol (DEACEG), and their aqueous solutions, over the complete composition range, at temperatures from (298.15 to 343.15) K. Densities and viscosities were measured using the vibrating tube and the falling ball techniques, respectively, while the refractive index at the sodium D line was measured using an automatic refractometer. We aimed to represent the measured properties as a function of temperature and composition, and correlated them using the Redlich–Kister-type equation, for density, a polynomial function, for refractive index, and the Vogel–Fulcher–Tammann (VFT) equation, for viscosity

Determination of the Real Loss of Power for a Condensing and a Backpressure Turbine by Means of Second Law Analysis

Directory of Open Access Journals (Sweden)

Henrik Holmberg

2009-10-01

Full Text Available All real processes generate entropy and the power/exergy loss is usually determined by means of the Gouy-Stodola law. If the system only exchanges heat at the environmental temperature, the Gouy-Stodola law gives the correct loss of power. However, most industrial processes exchange heat at higher or lower temperatures than the actual environmental temperature. When calculating the real loss of power in these cases, the Gouy-Stodola law does not give the correct loss if the actual environmental temperature is used. The first aim of this paper is to show through simple steam turbine examples that the previous statement is true. The second aim of the paper is to define the effective temperature to calculate the real power loss of the system with the Gouy-Stodola law, and to apply it to turbine examples. Example calculations also show that the correct power loss can be defined if the effective temperature is used instead of the real environmental temperature.

Technological characteristics of meat - viscosity

OpenAIRE

DIBĎÁK, Tomáš

2012-01-01

This bachelor thesis is focused on the technological characteristics of meat, mainly viscosity of meat. At the beginning I dealt with construction of meat and various types of meat: beef, veal, pork, mutton, rabbit, poultry and venison. Then I described basic chemical composition of meat and it?s characteristic. In detail I dealt with viscosity of meat. Viscosity is the ability of meat to bind water both own and added. I mentioned influences, which effects viscosity and I presented the possib...

Power-law tails and non-Markovian dynamics in open quantum systems: An exact solution from Keldysh field theory

Science.gov (United States)

Chakraborty, Ahana; Sensarma, Rajdeep

2018-03-01

The Born-Markov approximation is widely used to study the dynamics of open quantum systems coupled to external baths. Using Keldysh formalism, we show that the dynamics of a system of bosons (fermions) linearly coupled to a noninteracting bosonic (fermionic) bath falls outside this paradigm if the bath spectral function has nonanalyticities as a function of frequency. In this case, we show that the dissipative and noise kernels governing the dynamics have distinct power-law tails. The Green's functions show a short-time "quasi"-Markovian exponential decay before crossing over to a power-law tail governed by the nonanalyticity of the spectral function. We study a system of bosons (fermions) hopping on a one-dimensional lattice, where each site is coupled linearly to an independent bath of noninteracting bosons (fermions). We obtain exact expressions for the Green's functions of this system, which show power-law decay ˜|t - t'|-3 /2 . We use these to calculate the density and current profile, as well as unequal-time current-current correlators. While the density and current profiles show interesting quantitative deviations from Markovian results, the current-current correlators show qualitatively distinct long-time power-law tails |t - t'|-3 characteristic of non-Markovian dynamics. We show that the power-law decays survive in the presence of interparticle interaction in the system, but the crossover time scale is shifted to larger values with increasing interaction strength.

SUBSTANTIAL EXCEPTIONS AND (DELIMITATIONS OF THE POWERS OF THE JUDGES ON CIVIL PROCEDURAL LAW

Directory of Open Access Journals (Sweden)

Igor Raatz

2017-08-01

Full Text Available This essay aims to unveil the role of the substantial exceptions on delimiting the powers of the judges on civil procedural law, especially regarding the ex officio judicial activity. This way, under a phenomenological method and based on a vision of guarantee of rights on procedural law, the article offers a brief explanation of the question concerning the content of the object under litigation and its role of (delimiting the powers of the judges. The work hypothesis is the addition of the substantial exceptions among the content of the object under litigation, along with the claim itself and the cause of action. The results lie on the premise that, by the substantial exceptions, the defendant extends the object under litigation – which is formed dynamically on civil procedure. The conclusion points towards the idea that the substantial exceptions act in a way of limiting the ex officio judicial activity on civil procedural law

Beta Function Quintessence Cosmological Parameters and Fundamental Constants I: Power and Inverse Power Law Dark Energy Potentials

Science.gov (United States)

Thompson, Rodger I.

2018-04-01

This investigation explores using the beta function formalism to calculate analytic solutions for the observable parameters in rolling scalar field cosmologies. The beta function in this case is the derivative of the scalar ϕ with respect to the natural log of the scale factor a, β (φ )=d φ /d ln (a). Once the beta function is specified, modulo a boundary condition, the evolution of the scalar ϕ as a function of the scale factor is completely determined. A rolling scalar field cosmology is defined by its action which can contain a range of physically motivated dark energy potentials. The beta function is chosen so that the associated "beta potential" is an accurate, but not exact, representation of the appropriate dark energy model potential. The basic concept is that the action with the beta potential is so similar to the action with the model potential that solutions using the beta action are accurate representations of solutions using the model action. The beta function provides an extra equation to calculate analytic functions of the cosmologies parameters as a function of the scale factor that are that are not calculable using only the model action. As an example this investigation uses a quintessence cosmology to demonstrate the method for power and inverse power law dark energy potentials. An interesting result of the investigation is that the Hubble parameter H is almost completely insensitive to the power of the potentials and that ΛCDM is part of the family of quintessence cosmology power law potentials with a power of zero.

Modification of rice starch by gamma irradiation to produce soluble starch of low viscosity for industrial purposes

International Nuclear Information System (INIS)

El Saadany, R.M.A.; El Saadany, F.M.; Foda, Y.H.

1974-01-01

Because starch of low viscosity is important for industrial purposes this research was carried out to study the possibility of producing this sort of starch by treating rice starch with γ-irradiation. Results indicated than when rice starch was modified by γ-irradiation, the reducing power increased and degradation as well as molecular breakdown occured followed by sharp decrease of its viscosity, specific viscosity and intrisinc viscosity. Results showed that starch became more soluble by treating with γ-irradiation and lost its resistance to water as its swelling capacity decreased. All these changes were proportional to the doses of γ-irradiation. (orig.) [de

Dynamic bounds for power and efficiency of non-ideal energy converters under nonlinear transfer laws

International Nuclear Information System (INIS)

Sieniutycz, Stanislaw

2009-01-01

We present a thermodynamic approach to simulation and modeling of nonlinear energy converters, in particular radiation engines. Novel results are obtained especially for dynamical engines when the temperature of the propelling medium decreases in time due to a continual decrease of the medium's internal energy caused by the power production. Basic thermodynamic principles determine the converter's efficiency and work limits in terms of the entropy production. The real work is a cumulative effect obtained in a system of a resource fluid, a sequence of engines, and an infinite bath. Nonlinear modeling involves dynamic optimization in which the classical expression for efficiency at maximum power is generalized to endoirreversible machines and nonlinear transfer laws. The primary result is a finite-rate generalization of the classical, reversible work potential (exergy). The generalized work function depends on thermal coordinates and a dissipation index, h, i.e. a Hamiltonian of the minimum entropy production problem. This generalized work function implies stronger bounds on work delivered or supplied than the reversible work potential. The role of the nonlinear analyses and dynamic optimization is shown especially for radiation engines. As an example of the kinetic work limit, generalized exergy of radiation fluid is estimated in terms of finite rates, quantified by the Hamiltonian h

Power laws reveal phase transitions in landscape controls of fire regimes

Science.gov (United States)

Donald McKenzie; Maureen C. Kennedy

2012-01-01

Understanding the environmental controls on historical wildfires, and how they changed across spatial scales, is difficult because there are no surviving explicit records of either weather or vegetation (fuels). Here we show how power laws associated with fire-event time series arise in limited domains of parameters that represent critical transitions in the controls...

Asymptotic expansion of unsteady gravity flow of a power-law fluid ...

African Journals Online (AJOL)

We present a paper on the asymptotic expansion of unsteady non-linear rheological effects of a power-law fluid under gravity. The fluid flows through a porous medium. The asymptotic expansion is employed to obtain solution of the nonlinear problem. The results show the existence of traveling waves. It is assumed that the ...

The Effects of Earth's Outer Core's Viscosity on Geodynamo Models

Science.gov (United States)

Dong, C.; Jiao, L.; Zhang, H.

2017-12-01

Geodynamo process is controlled by mathematic equations and input parameters. To study effects of parameters on geodynamo system, MoSST model has been used to simulate geodynamo outputs under different outer core's viscosity ν. With spanning ν for nearly three orders when other parameters fixed, we studied the variation of each physical field and its typical length scale. We find that variation of ν affects the velocity field intensely. The magnetic field almost decreases monotonically with increasing of ν, while the variation is no larger than 30%. The temperature perturbation increases monotonically with ν, but by a very small magnitude (6%). The averaged velocity field (u) of the liquid core increases with ν as a simple fitted scaling relation: u∝ν0.49. The phenomenon that u increases with ν is essentially that increasing of ν breaks the Taylor-Proudman constraint and drops the critical Rayleigh number, and thus u increases under the same thermal driving force. Forces balance is analyzed and balance mode shifts with variation of ν. When compared with former studies of scaling laws, this study supports the conclusion that in a certain parameter range, the magnetic field strength doesn't vary much with the viscosity, but opposes to the assumption that the velocity field has nothing to do with the outer core viscosity.

Focus-based filtering + clustering technique for power-law networks with small world phenomenon

Science.gov (United States)

Boutin, François; Thièvre, Jérôme; Hascoët, Mountaz

2006-01-01

Realistic interaction networks usually present two main properties: a power-law degree distribution and a small world behavior. Few nodes are linked to many nodes and adjacent nodes are likely to share common neighbors. Moreover, graph structure usually presents a dense core that is difficult to explore with classical filtering and clustering techniques. In this paper, we propose a new filtering technique accounting for a user-focus. This technique extracts a tree-like graph with also power-law degree distribution and small world behavior. Resulting structure is easily drawn with classical force-directed drawing algorithms. It is also quickly clustered and displayed into a multi-level silhouette tree (MuSi-Tree) from any user-focus. We built a new graph filtering + clustering + drawing API and report a case study.

Numerical convergence of the self-diffusion coefficient and viscosity obtained with Thomas-Fermi-Dirac molecular dynamics

Science.gov (United States)

Danel, J.-F.; Kazandjian, L.; Zérah, G.

2012-06-01

Computations of the self-diffusion coefficient and viscosity in warm dense matter are presented with an emphasis on obtaining numerical convergence and a careful evaluation of the standard deviation. The transport coefficients are computed with the Green-Kubo relation and orbital-free molecular dynamics at the Thomas-Fermi-Dirac level. The numerical parameters are varied until the Green-Kubo integral is equal to a constant in the t→+∞ limit; the transport coefficients are deduced from this constant and not by extrapolation of the Green-Kubo integral. The latter method, which gives rise to an unknown error, is tested for the computation of viscosity; it appears that it should be used with caution. In the large domain of coupling constant considered, both the self-diffusion coefficient and viscosity turn out to be well approximated by simple analytical laws using a single effective atomic number calculated in the average-atom model.

The relationship between randomness and power-law distributed move lengths in random walk algorithms

Science.gov (United States)

Sakiyama, Tomoko; Gunji, Yukio-Pegio

2014-05-01

Recently, we proposed a new random walk algorithm, termed the REV algorithm, in which the agent alters the directional rule that governs it using the most recent four random numbers. Here, we examined how a non-bounded number, i.e., "randomness" regarding move direction, was important for optimal searching and power-law distributed step lengths in rule change. We proposed two algorithms: the REV and REV-bounded algorithms. In the REV algorithm, one of the four random numbers used to change the rule is non-bounded. In contrast, all four random numbers in the REV-bounded algorithm are bounded. We showed that the REV algorithm exhibited more consistent power-law distributed step lengths and flexible searching behavior.

Formulation and experimental evaluation of closed-form control laws for the rapid maneuvering of reactor neutronic power

International Nuclear Information System (INIS)

Bernard, J.A.

1989-09-01

This report describes both the theoretical development and the experimental evaluation of a novel, robust methodology for the time-optimal adjustment of a reactor's neutronic power under conditions of closed-loop digital control. Central to the approach are the 'MIT-SNL Period-Generated Minimum Time Control Laws' which determine the rate at which reactivity should be changed in order to cause a reactor's neutronic power to conform to a specified trajectory. Using these laws, reactor power can be safely raised by five to seven orders of magnitude in a few seconds. The MIT-SNL laws were developed to facilitate rapid increases of neutronic power on spacecraft reactors operating in an SDI environment. However, these laws are generic and have other applications including the rapid recovery of research and test reactors subsequent to an unanticipated shutdown, power increases following the achievement of criticality on commercial reactors, power adjustments on commercial reactors so as to minimize thermal stress, and automated startups. The work reported here was performed by the Massachusetts Institute of Technology under contract to the Sandia National Laboratories. Support was also provided by the US Department of Energy's Division of University and Industry Programs. The work described in this report is significant in that a novel solution to the problem of time-optimal control of neutronic power was identified, in that a rigorous description of a reactor's dynamics was derived in that the rate of change of reactivity was recognized as the proper control signal, and in that extensive experimental trials were conducted of these newly developed concepts on actual nuclear reactors. 43 refs., 118 figs., 11 tabs

Evidence for intermittency and a truncated power law from highly resolved aphid movement data.

Science.gov (United States)

Mashanova, Alla; Oliver, Tom H; Jansen, Vincent A A

2010-01-06

Power laws are increasingly used to describe animal movement. Despite this, the use of power laws has been criticized on both empirical and theoretical grounds, and alternative models based on extensions of conventional random walk theory (Brownian motion) have been suggested. In this paper, we analyse a large volume of data of aphid walking behaviour (65,068 data points), which provides a highly resolved dataset to investigate the pattern of movement. We show that aphid movement is intermittent--with alternations of a slow movement with frequent change of direction and a fast, relatively directed movement--and that the fast movement consists of two phases--a strongly directed phase that gradually changes into an uncorrelated random walk. By measuring the mean-squared displacement and the duration of non-stop movement episodes we found that both spatial and temporal aspects of aphid movement are best described using a truncated power law approach. We suggest that the observed spatial pattern arises from the duration of non-stop movement phases rather than from correlations in turning angles. We discuss the implications of these findings for interpreting movement data, such as distinguishing between movement and non-movement, and the effect of the range of data used in the analysis on the conclusions.

Capillary waves with surface viscosity

Science.gov (United States)

Shen, Li; Denner, Fabian; Morgan, Neal; van Wachem, Berend; Dini, Daniele

2017-11-01

Experiments over the last 50 years have suggested a correlation between the surface (shear) viscosity and the stability of a foam or emulsion. With recent techniques allowing more accurate measurements of the elusive surface viscosity, we examine this link theoretically using small-amplitude capillary waves in the presence of the Marangoni effect and surface viscosity modelled via the Boussinesq-Scriven model. The surface viscosity effect is found to contribute a damping effect on the amplitude of the capillary wave with subtle differences to the effect of the convective-diffusive Marangoni transport. The general wave dispersion is augmented to take into account the Marangoni and surface viscosity effects, and a first-order correction to the critical damping wavelength is derived. The authors acknowledge the financial support of the Shell University Technology Centre for fuels and lubricants.

Comparative power law analysis of structured breast phantom and patient images in digital mammography and breast tomosynthesis.

Science.gov (United States)

Cockmartin, L; Bosmans, H; Marshall, N W

2013-08-01

This work characterizes three candidate mammography phantoms with structured background in terms of power law analysis in the low frequency region of the power spectrum for 2D (planar) mammography and digital breast tomosynthesis (DBT). The study was performed using three phantoms (spheres in water, Voxmam, and BR3D CIRS phantoms) on two DBT systems from two different vendors (Siemens Inspiration and Hologic Selenia Dimensions). Power spectra (PS) were calculated for planar projection, DBT projection, and reconstructed images and curve fitted in the low frequency region from 0.2 to 0.7 mm(-1) with a power law function characterized by an exponent β and magnitude κ. The influence of acquisition dose and tube voltage on the power law parameters was first explored. Then power law parameters were calculated from images acquired with the same anode∕filter combination and tube voltage for the three test objects, and compared with each other. Finally, PS curves for automatic exposure controlled acquisitions (anode∕filter combination and tube voltages selected by the systems based on the breast equivalent thickness of the test objects) were compared against PS analysis performed on patient data (for Siemens 80 and for Hologic 48 mammograms and DBT series). Dosimetric aspects of the three test objects were also examined. The power law exponent (β) was found to be independent of acquisition dose for planar mammography but varied more for DBT projections of the sphere-phantom. Systematic increase of tube voltage did not affect β but decreased κ, both in planar and DBT projection phantom images. Power spectra of the BR3D phantom were closer to those of the patients than these of the Voxmam phantom; the Voxmam phantom gave high values of κ compared to the other phantoms and the patient series. The magnitude of the PS curves of the BR3D phantom was within the patient range but β was lower than the average patient value. Finally, PS magnitude for the sphere

Self-diffusion coefficients and shear viscosity of inverse power fluids: from hard- to soft-spheres.

Science.gov (United States)

Heyes, D M; Brańka, A C

2008-07-21

Molecular dynamics computer simulation has been used to compute the self-diffusion coefficient, D, and shear viscosity, eta(s), of soft-sphere fluids, in which the particles interact through the soft-sphere or inverse power pair potential, phi(r) = epsilon(sigma/r)(n), where n measures the steepness or stiffness of the potential, and epsilon and sigma are a characteristic energy and distance, respectively. The simulations were carried out on monodisperse systems for a range of n values from the hard-sphere (n --> infinity) limit down to n = 4, and up to densities in excess of the fluid-solid co-existence value. A new analytical procedure is proposed which reproduces the transport coefficients at high densities, and can be used to extrapolate the data to densities higher than accurately accessible by simulation or experiment, and tending to the glass transition. This formula, DX(c-1) proportional, variant A/X + B, where c is an adjustable parameter, and X is either the packing fraction or the pressure, is a development of one proposed by Dymond. In the expression, -A/B is the value of X at the ideal glass transition (i.e., where D and eta(s)(-1) --> 0). Estimated values are presented for the packing fraction and the pressure at the glass transition for n values between the hard and soft particle limits. The above expression is also shown to reproduce the high density viscosity data of supercritical argon, krypton and nitrogen. Fits to the soft-sphere simulation transport coefficients close to solid-fluid co-existence are also made using the analytic form, ln(D) = alpha(X)X, and n-dependence of the alpha(X) is presented (X is either the packing fraction or the pressure).

On the Nature of the Variability Power Decay towards Soft Spectral States in X-Ray Binaries. Case Study in Cyg X-1

Science.gov (United States)

Titarchuk, Lev; Shaposhinikov, Nikolai

2007-01-01

A characteristic feature of the Fourier Power Density Spectrum (PDS) observed from black hole X-ray binaries in low/hard and intermediate spectral states is a broad band-limited noise, characterized by a constant below some frequency (a "break" frequency) and a power law above this frequency. It has been shown that the variability of this type can be produced by the inward diffusion of the local driving perturbations in a bounded configuration (accretion disk or corona). In the framework of this model, the perturbation diffusion time to is related to the phenomenological break frequency, while the PDS power-law slope above the "break" is determined by the viscosity distribution over the configuration. The perturbation diffusion scenario explains the decay of the power of X-ray variability observed in a number of compact sources (containing black hole and neutron star) during an evolution of theses sources from low/hard to high/soft states. We compare the model predictions with the subset of data from Cyg X-1 collected by the Rossi X-ray Time Explorer (RXTE). Our extensive analysis of the Cyg X-1 PDSs demonstrates that the observed integrated power P(sub x), decreases approximately as a square root of the characteristic frequency of the driving oscillations v(sub dr). The RXTE observations of Cyg X-1 allow us to infer P(sub dr), and t(sub o) as a function of v(sub dr). We also apply the basic parameters of observed PDSs, power-law index and low frequency quasiperiodic oscillations. to infer Reynolds (Re) number from the observations using the method developed in our previous paper. Our analysis shows that Re-number increases from values about 10 in low/hard state to that about 70 during the high/soft state. Subject headings: accretion, accretion disks-black hole physics-stars:individual (Cyg X-1) :radiation mechanisms: nonthermal-physical data and processes

Densities and viscosities for ionic liquids mixtures containing [eOHmim][BF4], [bmim][BF4] and [bpy][BF4

International Nuclear Information System (INIS)

Song, Dayong; Chen, Jing

2014-01-01

Highlights: • Targets of this research are ILs mixtures. • Densities and viscosities were measured for three ILs mixtures. • Excess molar properties were deduced from the experiments. • Viscosities were discussed by the ideal Grunberg and Nissan mixing law. - Abstract: Densities and viscosities of binary ionic liquids mixtures, 1-(2-hydroxyethyl)-3-methylimidazolium tetrafluoroborate ([eOHmim][BF 4 ]) + 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF 4 ]), 1-(2-hydroxyethyl)-3-methylimidazolium tetrafluoroborate ([eOHmim][BF 4 ]) + N-butylpyridinium tetrafluoroborate ([bpy][BF 4 ]) and 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF 4 ]) + N-butylpyridinium tetrafluoroborate ([bpy][BF 4 ]) were measured over the entire mole fraction from T = (298.15 to 343.15) K. The excess molar volumes were calculated and correlated by Redlich–Kiser polynomial expansions. The viscosities for pure ionic liquids were analyzed by means of the Vogel–Tammann–Fulcher equation and ideal mixing rules were applied for the ILs mixtures

Inertia effects in the laminar radial flow of a power law fluid with an electromagnetic field

International Nuclear Information System (INIS)

Chen, C.-K.; Chen, K.-H.; Wu, C.-Y.

1984-01-01

An approximate study of the pressure distribution for the radial flow of a non-newtonian (power law) fluid between two parallel disks in the presence of an axial electrical field is obtained by using the momentum and energy integral methods. For a non-newtonian fluid it is shown that the inertia effect must be considered to be significant for the pressure distribution, especially for the power law fluids with n >= 1. Furthermore, it is seen that the inertia effect will also lower the load capacity of the disks. (Auth.)

Power-law neuronal fluctuations in a recurrent network model of parametric working memory.

Science.gov (United States)

Miller, Paul; Wang, Xiao-Jing

2006-02-01

In a working memory system, persistent activity maintains information in the absence of external stimulation, therefore the time scale and structure of correlated neural fluctuations reflect the intrinsic microcircuit dynamics rather than direct responses to sensory inputs. Here we show that a parametric working memory model capable of graded persistent activity is characterized by arbitrarily long correlation times, with Fano factors and power spectra of neural activity described by the power laws of a random walk. Collective drifts of the mnemonic firing pattern induce long-term noise correlations between pairs of cells, with the sign (positive or negative) and amplitude proportional to the product of the gradients of their tuning curves. None of the power-law behavior was observed in a variant of the model endowed with discrete bistable neural groups, where noise fluctuations were unable to cause long-term changes in rate. Therefore such behavior can serve as a probe for a quasi-continuous attractor. We propose that the unusual correlated fluctuations have important implications for neural coding in parametric working memory circuits.

Converging cylindrical magnetohydrodynamic shock collapse onto a power-law-varying line current

KAUST Repository

Mostert, W.; Pullin, D. I.; Samtaney, Ravi; Wheatley, V.

2016-01-01

We investigate the convergence behaviour of a cylindrical, fast magnetohydrodynamic (MHD) shock wave in a neutrally ionized gas collapsing onto an axial line current that generates a power law in time, azimuthal magnetic field. The analysis is done

Spectral derivation of the classic laws of wall-bounded turbulent flows.

Science.gov (United States)

Gioia, Gustavo; Chakraborty, Pinaki

2017-08-01

We show that the classic laws of the mean-velocity profiles (MVPs) of wall-bounded turbulent flows-the 'law of the wall,' the 'defect law' and the 'log law'-can be predicated on a sufficient condition with no manifest ties to the MVPs, namely that viscosity and finite turbulent domains have a depressive effect on the spectrum of turbulent energy. We also show that this sufficient condition is consistent with empirical data on the spectrum and may be deemed a general property of the energetics of wall turbulence. Our findings shed new light on the physical origin of the classic laws and their immediate offshoot, Prandtl's theory of turbulent friction.

Floquet states of a kicked particle in a singular potential: Exponential and power-law profiles

Science.gov (United States)

Paul, Sanku; Santhanam, M. S.

2018-03-01

It is well known that, in the chaotic regime, all the Floquet states of kicked rotor system display an exponential profile resulting from dynamical localization. If the kicked rotor is placed in an additional stationary infinite potential well, its Floquet states display power-law profile. It has also been suggested in general that the Floquet states of periodically kicked systems with singularities in the potential would have power-law profile. In this work, we study the Floquet states of a kicked particle in finite potential barrier. By varying the height of finite potential barrier, the nature of transition in the Floquet state from exponential to power-law decay profile is studied. We map this system to a tight-binding model and show that the nature of decay profile depends on energy band spanned by the Floquet states (in unperturbed basis) relative to the potential height. This property can also be inferred from the statistics of Floquet eigenvalues and eigenvectors. This leads to an unusual scenario in which the level spacing distribution, as a window in to the spectral correlations, is not a unique characteristic for the entire system.

Axial annular flow of power-law fluids - applicability of the limiting cases

Czech Academy of Sciences Publication Activity Database

Filip, Petr; David, Jiří

2007-01-01

Roč. 52, č. 4 (2007), s. 365-371 ISSN 0001-7043 R&D Projects: GA ČR GA103/06/1033 Institutional research plan: CEZ:AV0Z20600510 Keywords : Concentric annuli * Poiseuile flow * annular flow * power- law fluids * flow rate * pressure drop Subject RIV: BK - Fluid Dynamics

Power spectrum analysis of polarized emission from the Canadian galactic plane survey

Energy Technology Data Exchange (ETDEWEB)

Stutz, R. A.; Rosolowsky, E. W. [University of British Columbia Okanagan, 3333 University Way, Kelowna BC, V1V 1V7 (Canada); Kothes, R.; Landecker, T. L. [National Research Council Canada, Dominion Radio Astrophysical Observatory, Box 248, Penticton, BC, V2A 6J9 (Canada)

2014-05-20

Angular power spectra are calculated and presented for the entirety of the Canadian Galactic Plane Survey polarization data set at 1.4 GHz covering an area of 1060 deg{sup 2}. The data analyzed are a combination of data from the 100 m Effelsberg Telescope, the 26 m Telescope at the Dominion Radio Astrophysical Observatory, and the Synthesis Telescope at the Dominion Radio Astrophysical Observatory, allowing all scales to be sampled down to arcminute resolution. The resulting power spectra cover multipoles from ℓ ≈ 60 to ℓ ≈ 10{sup 4} and display both a power-law component at low multipoles and a flattening at high multipoles from point sources. We fit the power spectrum with a model that accounts for these components and instrumental effects. The resulting power-law indices are found to have a mode of 2.3, similar to previous results. However, there are significant regional variations in the index, defying attempts to characterize the emission with a single value. The power-law index is found to increase away from the Galactic plane. A transition from small-scale to large-scale structure is evident at b = 9°, associated with the disk-halo transition in a 15° region around l = 108°. Localized variations in the index are found toward H II regions and supernova remnants, but the interpretation of these variations is inconclusive. The power in the polarized emission is anticorrelated with bright thermal emission (traced by Hα emission) indicating that the thermal emission depolarizes background synchrotron emission.

Anisotropic power spectrum of refractive-index fluctuation in hypersonic turbulence.

Science.gov (United States)

Li, Jiangting; Yang, Shaofei; Guo, Lixin; Cheng, Mingjian

2016-11-10

An anisotropic power spectrum of the refractive-index fluctuation in hypersonic turbulence was obtained by processing the experimental image of the hypersonic plasma sheath and transforming the generalized anisotropic von Kármán spectrum. The power spectrum suggested here can provide as good a fit to measured spectrum data for hypersonic turbulence as that recorded from the nano-planar laser scattering image. Based on the newfound anisotropic hypersonic turbulence power spectrum, Rytov approximation was employed to establish the wave structure function and the spatial coherence radius model of electromagnetic beam propagation in hypersonic turbulence. Enhancing the anisotropy characteristics of the hypersonic turbulence led to a significant improvement in the propagation performance of electromagnetic beams in hypersonic plasma sheath. The influence of hypersonic turbulence on electromagnetic beams increases with the increase of variance of the refractive-index fluctuation and the decrease of turbulence outer scale and anisotropy parameters. The spatial coherence radius was much smaller than that in atmospheric turbulence. These results are fundamental to understanding electromagnetic wave propagation in hypersonic turbulence.

The Forbes 400, the Pareto power-law and efficient markets

Science.gov (United States)

Klass, O. S.; Biham, O.; Levy, M.; Malcai, O.; Solomon, S.

2007-01-01

Statistical regularities at the top end of the wealth distribution in the United States are examined using the Forbes 400 lists of richest Americans, published between 1988 and 2003. It is found that the wealths are distributed according to a power-law (Pareto) distribution. This result is explained using a simple stochastic model of multiple investors that incorporates the efficient market hypothesis as well as the multiplicative nature of financial market fluctuations.

A technique for evaluating the oil/heavy-oil viscosity changes under ultrasound in a simulated porous medium.

Science.gov (United States)

Hamidi, Hossein; Mohammadian, Erfan; Junin, Radzuan; Rafati, Roozbeh; Manan, Mohammad; Azdarpour, Amin; Junid, Mundzir

2014-02-01

Theoretically, Ultrasound method is an economical and environmentally friendly or "green" technology, which has been of interest for more than six decades for the purpose of enhancement of oil/heavy-oil production. However, in spite of many studies, questions about the effective mechanisms causing increase in oil recovery still existed. In addition, the majority of the mechanisms mentioned in the previous studies are theoretical or speculative. One of the changes that could be recognized in the fluid properties is viscosity reduction due to radiation of ultrasound waves. In this study, a technique was developed to investigate directly the effect of ultrasonic waves (different frequencies of 25, 40, 68 kHz and powers of 100, 250, 500 W) on viscosity changes of three types of oil (Paraffin oil, Synthetic oil, and Kerosene) and a Brine sample. The viscosity calculations in the smooth capillary tube were based on the mathematical models developed from the Poiseuille's equation. The experiments were carried out for uncontrolled and controlled temperature conditions. It was observed that the viscosity of all the liquids was decreased under ultrasound in all the experiments. This reduction was more significant for uncontrolled temperature condition cases. However, the reduction in viscosity under ultrasound was higher for lighter liquids compare to heavier ones. Pressure difference was diminished by decreasing in the fluid viscosity in all the cases which increases fluid flow ability, which in turn aids to higher oil recovery in enhanced oil recovery (EOR) operations. Higher ultrasound power showed higher liquid viscosity reduction in all the cases. Higher ultrasound frequency revealed higher and lower viscosity reduction for uncontrolled and controlled temperature condition experiments, respectively. In other words, the reduction in viscosity was inversely proportional to increasing the frequency in temperature controlled experiments. It was concluded that cavitation

Analysis of diodes used as precision power detectors above the square law region

DEFF Research Database (Denmark)

Guldbrandsen, Tom

1990-01-01

The deviation from square law found in diode power detectors at moderate power levels has been modeled for a general system consisting of a number of diode detectors connected to a common arbitrary linear passive network, containing an approximately sinusoidal source. This situation covers the case...... if an extra-set of measurements is made in situ. For precision measurements the maximum power level can be increased by about 10 dB. The dynamic range can thus be increased sufficiently to enable fast measurements to be made with an accuracy of 10-3 dB...

Effect of ionic and non-ionic contrast media on whole blood viscosity, plasma viscosity and hematocrit in vitro

International Nuclear Information System (INIS)

Aspelin, P.

1978-01-01

The effect of the ionic contrast media diatrizoate, iocarmate and metrizoate and the non-ionic metrizamide on whole blood viscosity, plasma viscosity and hematocrit was investigated. All the contrast media increased whole blood and plasma viscosity and reduced the hematocrit. The whole blood viscosity increased with increasing osmolality of the contrast medium solutions, whereas the plasma viscosity increased with increasing viscosity of the contrast medium solutions. The higher the osmolality of the contrast media, the lower the hematocrit became. The normal shear-thinning (decreasing viscosity with increasing shear rate) property of blood was reduced when contrast medium was added to the blood. At 50 per cent volume ratio (contrast medium to blood), the ionic contrast media converted the blood into a shear-thickening (increasing viscosity with increasing shear rate) suspension, indicating a marked rigidification of the single red cell, while the non-ionic contrast medium still produced shear-thinning, indicating less rigidification of the red cell (p<0.01). (Auth.)

Chaotic improved PSO-based multi-objective optimization for minimization of power losses and L index in power systems

International Nuclear Information System (INIS)

Chen, Gonggui; Liu, Lilan; Song, Peizhu; Du, Yangwei

2014-01-01

Highlights: • New method for MOORPD problem using MOCIPSO and MOIPSO approaches. • Constrain-prior Pareto-dominance method is proposed to meet the constraints. • The limits of the apparent power flow of transmission line are considered. • MOORPD model is built up for MOORPD problem. • The achieved results by MOCIPSO and MOIPSO approaches are better than MOPSO method. - Abstract: Multi-objective optimal reactive power dispatch (MOORPD) seeks to not only minimize power losses, but also improve the stability of power system simultaneously. In this paper, the static voltage stability enhancement is achieved through incorporating L index in MOORPD problem. Chaotic improved PSO-based multi-objective optimization (MOCIPSO) and improved PSO-based multi-objective optimization (MOIPSO) approaches are proposed for solving complex multi-objective, mixed integer nonlinear problems such as minimization of power losses and L index in power systems simultaneously. In MOCIPSO and MOIPSO based optimization approaches, crossover operator is proposed to enhance PSO diversity and improve their global searching capability, and for MOCIPSO based optimization approach, chaotic sequences based on logistic map instead of random sequences is introduced to PSO for enhancing exploitation capability. In the two approaches, constrain-prior Pareto-dominance method (CPM) is proposed to meet the inequality constraints on state variables, the sorting and crowding distance methods are considered to maintain a well distributed Pareto optimal solutions, and moreover, fuzzy set theory is employed to extract the best compromise solution over the Pareto optimal curve. The proposed approaches have been examined and tested in the IEEE 30 bus and the IEEE 57 bus power systems. The performances of MOCIPSO, MOIPSO, and multi-objective PSO (MOPSO) approaches are compared with respect to multi-objective performance measures. The simulation results are promising and confirm the ability of MOCIPSO and

Association of rule of law and health outcomes: an ecological study

Science.gov (United States)

Pinzon-Rondon, Angela Maria; Attaran, Amir; Botero, Juan Carlos; Ruiz-Sternberg, Angela Maria

2015-01-01

Objectives To explore whether the rule of law is a foundational determinant of health that underlies other socioeconomic, political and cultural factors that have been associated with health outcomes. Setting Global project. Participants Data set of 96 countries, comprising 91% of the global population. Primary and secondary outcome measures The following health indicators, infant mortality rate, maternal mortality rate, life expectancy, and cardiovascular disease and diabetes mortality rate, were included to explore their association with the rule of law. We used a novel Rule of Law Index, gathered from survey sources, in a cross-sectional and ecological design. The Index is based on eight subindices: (1) Constraints on Government Powers; (2) Absence of Corruption; (3) Order and Security; (4) Fundamental Rights; (5) Open Government; (6) Regulatory Enforcement, (7) Civil Justice; and (8) Criminal Justice. Results The rule of law showed an independent association with infant mortality rate, maternal mortality rate, life expectancy, and cardiovascular disease and diabetes mortality rate, after adjusting for the countries’ level of per capita income, their expenditures in health, their level of political and civil freedom, their Gini measure of inequality and women's status (pconstitute a structural barrier to health improvement. PMID:26515684

Comment on "Time needed to board an airplane: a power law and the structure behind it".

Science.gov (United States)

Bernstein, Noam

2012-08-01

Frette and Hemmer [Phys. Rev. E 85, 011130 (2012)] recently showed that for a simple model for the boarding of an airplane, the mean time to board scales as a power law with the number of passengers N and the exponent is less than 1. They note that this scaling leads to the prediction that the "back-to-front" strategy, where passengers are divided into groups from contiguous ranges of rows and each group is allowed to board in turn from back to front once the previous group has found their seats, has a longer boarding time than would a single group. Here I extend their results to a larger number of passengers using a sampling approach and explore a scenario where the queue is presorted into groups from back to front, but allowed to enter the plane as soon as they can. I show that the power law dependence on passenger numbers is different for large N and that there is a boarding time reduction for presorted groups, with a power law dependence on the number of presorted groups.

True Multilateral Indexes for International Comparisons of Purchasing Power and Real Income

OpenAIRE

J.P. Neary

1997-01-01

I consider the problem of choosing index numbers of purchasing power and real income for international comparisons. I show that the desirable properties of methods based on the Fisher "Ideal" index do not extend to multilateral comparisons, except when tastes are homothetic. By contrast, the Geary method, which underlies the Penn World Tables, provides an approximation to a set of "true" exchange rate indexes which have many desirable properties. In particular, if demands exhibit generalized ...

The viscosity of dimethyl ether

DEFF Research Database (Denmark)

Sivebæk, Ion Marius; Jakobsen, Jørgen

2007-01-01

and NOx traps are installed. The most significant problem encountered when engines are fuelled with DME is that the injection equipment breaks down prematurely due to extensive wear. This tribology issue can be explained by the very low lubricity and viscosity of DME. Recently, laboratory methods have...... appeared capable of measuring these properties of DME. The development of this is rendered difficult because DME has to be pressurised to remain in the liquid state and it dissolves most of the commercially available elastomers. This paper deals fundamentally with the measurement of the viscosity of DME...... and extends the discussion to the difficulty of viscosity establishing of very thin fluids. The main issue here is that it is not easy to calibrate the viscometers in the very low viscosity range corresponding to about one-fifth of that of water. The result is that the low viscosity is measured at high...

On the classical theory of ordinary linear differential equations of the second order and the Schroedinger equation for power law potentials

International Nuclear Information System (INIS)

Lima, M.L.; Mignaco, J.A.

1983-01-01

The power law potentials in the Schroedinger equation solved recently are shown to come from the classical treatment of the singularities of a linear, second order differential equation. This allows to enlarge the class of solvable power law potentials. (Author) [pt

The enforcement order for the law for arrangement of surrounding areas of power generating facilities

International Nuclear Information System (INIS)

1979-01-01

The order is defined under the law for arrangement of surrounding areas of power generating facilities. Establishers of power generating facilities shall be hereunder general electric enterprisers, wholesale electric enterprisers and the Power Reactor and Nuclear Fuel Development Corporation. The scale of power generating facilities provided by the order is 350,000 kilo-watts for atomic and steam power generation and 5,000 kilo-watts for hydroelectric power. Equipment closely related to atomic power generation shall include facilities for reprocessing and examination of nuclear fuel materials spent for power generating reactors, reactors used for research of the safety of power generating reactors, experimental fast breeding reactors and experimental uranium enrichment facilities. Requisites for the extent of industrial accumulation are that the area belongs to those self-governing bodies whose industrial accumulation is more than the 8th degree. Public facilities specified are those for communication, sports or recreation, environmental hygiene, education and culture, medicine, social welfare, fire fighting and heat supplying, etc. Governors of the prefectures shall file arrangement programs to the Minister in charge through the Minister of International Trade and Industry to get the permission stipulated by the law. Subsidies shall not be paid to those enterprises which are executed by the government or a part of the expenses is born or supported by it. (Okada, K.)

Neste Oy starts the production of extra high viscosity index lubricating oil in Porvoo

International Nuclear Information System (INIS)

Kilander, H.

1997-01-01

Neste Oy is starting the manufacture of basic oil, used in advanced motor lubricants, in Finland. The plant will start the manufacture of the EHVI (Extra High Viscosity) by the end of 1997. The EHVI basic oil is a synthetic-like oil product, suitable for manufacture of high-quality lubricants. In the beginning the production of the basic oil will be about 50 000 tons/a. The investment costs of the plants are 180 million FIM

Laboratory constraints on chameleon dark energy and power-law fields

OpenAIRE

Steffen, Jason H.; Upadhye, Amol; Baumbaugh, Al; Chou, Aaron S.; Mazur, Peter O.; Tomlin, Ray; Weltman, Amanda; Wester, William

2010-01-01

We report results from the GammeV Chameleon Afterglow Search---a search for chameleon particles created via photon/chameleon oscillations within a magnetic field. This experiment is sensitive to a wide class of chameleon power-law models and dark energy models not previously explored. These results exclude five orders of magnitude in the coupling of chameleons to photons covering a range of four orders of magnitude in chameleon effective mass and, for individual chameleon models, exclude betw...

Laboratory Constraints on Chameleon Dark Energy and Power-Law Fields

International Nuclear Information System (INIS)

Steffen, J. H.; Baumbaugh, A.; Chou, A. S.; Mazur, P. O.; Tomlin, R.; Wester, W.; Upadhye, A.; Weltman, A.

2010-01-01

We report results from a search for chameleon particles created via photon-chameleon oscillations within a magnetic field. This experiment is sensitive to a wide class of unexplored chameleon power-law and dark energy models. These results exclude 5 orders of magnitude in the coupling of chameleons to photons covering a range of 4 orders of magnitude in chameleon effective mass and, for individual models, exclude between 4 and 12 orders of magnitude in chameleon couplings to matter.

The rule of law

Directory of Open Access Journals (Sweden)

Besnik Murati

2015-07-01

Full Text Available The state as an international entity and its impact on the individual’s right has been and still continues to be a crucial factor in the relationship between private and public persons. States vary in terms of their political system, however, democratic states are based on the separation of powers and human rights within the state. Rule of law is the product of many actors in a state, including laws, individuals, society, political system, separation of powers, human rights, the establishment of civil society, the relationship between law and the individual, as well as, individual-state relations. Purpose and focus of this study is the importance of a functioning state based on law, characteristics of the rule of law, separation of powers and the basic concepts of the rule of law.

Flow of power-law fluids in fixed beds of cylinders or spheres

KAUST Repository

Singh, John P.; Padhy, Sourav; Shaqfeh, Eric S. G.; Koch, Donald L.

2012-01-01

is influenced by the Newtonian fluid stress and a body force representing the linear drag on the surrounding particles. We consider a similar analysis for a power-law fluid where the stress τ is related to the rate of strain e by τ = 2m en-1e, where m and n

On minimally parametric primordial power spectrum reconstruction and the evidence for a red tilt