WorldWideScience

Sample records for random thermal motion

  1. Disentangling random thermal motion of particles and collective expansion of source from transverse momentum spectra in high energy collisions

    Science.gov (United States)

    Wei, Hua-Rong; Liu, Fu-Hu; Lacey, Roy A.

    2016-12-01

    In the framework of a multisource thermal model, we describe experimental results of the transverse momentum spectra of final-state light flavor particles produced in gold-gold (Au-Au), copper-copper (Cu-Cu), lead-lead (Pb-Pb), proton-lead (p-Pb), and proton-proton (p -p) collisions at various energies, measured by the PHENIX, STAR, ALICE, and CMS Collaborations, by using the Tsallis-standard (Tsallis form of Fermi-Dirac or Bose-Einstein), Tsallis, and two- or three-component standard distributions which can be in fact regarded as different types of ‘thermometers’ or ‘thermometric scales’ and ‘speedometers’. A central parameter in the three distributions is the effective temperature which contains information on the kinetic freeze-out temperature of the emitting source and reflects the effects of random thermal motion of particles as well as collective expansion of the source. To disentangle both effects, we extract the kinetic freeze-out temperature from the intercept of the effective temperature (T) curve as a function of particle’s rest mass (m 0) when plotting T versus m 0, and the mean transverse flow velocity from the slope of the mean transverse momentum ( ) curve as a function of mean moving mass (\\overline{m}) when plotting versus \\overline{m}.

  2. Random motion and Brownian rotation

    International Nuclear Information System (INIS)

    Wyllie, G.

    1980-01-01

    The course is centred on the Brownian motion - the random movement of molecules arising from thermal fluctuations of the surrounding medium - and starts with the classical theory of A. Einstein, M.v. Smoluchowski and P. Langevin. The first part of this article is quite elementary, and several of the questions raised in it have been instructively treated in a much more sophisticated way in recent reviews by Pomeau and Resibois and by Fox. This simple material may nevertheless be helpful to some readers whose main interest lies in approaching the work on Brownian rotation reviewed in the latter part of the present article. The simplest, and most brutally idealised, problem in our field of interest is that of the random walk in one dimension of space. Its solution leads on, through the diffusivity-mobility relation of Einstein, to Langevin's treatment of the Brownian motion. The application of these ideas to the movement of a molecule in a medium of similar molecules is clearly unrealistic, and much energy has been devoted to finding a suitable generalisation. We shall discuss in particular ideas due to Green, Zwanzig and Mori. (orig./WL)

  3. Brownian motion in short range random potentials

    International Nuclear Information System (INIS)

    Romero, A.H.; Romero, A.H.; Sancho, J.M.

    1998-01-01

    A numerical study of Brownian motion of noninteracting particles in random potentials is presented. The dynamics are modeled by Langevin equations in the high friction limit. The random potentials are Gaussian distributed and short ranged. The simulations are performed in one and two dimensions. Different dynamical regimes are found and explained. Effective subdiffusive exponents are obtained and commented on. copyright 1998 The American Physical Society

  4. Chaos the science of predictable random motion

    CERN Document Server

    Kautz, Richard

    2011-01-01

    Based on only elementary mathematics, this engaging account of chaos theory bridges the gap between introductions for the layman and college-level texts. It develops the science of dynamics in terms of small time steps, describes the phenomenon of chaos through simple examples, and concludes with a close look at a homoclinic tangle, the mathematical monster at the heart of chaos. The presentation is enhanced by many figures, animations of chaotic motion (available on a companion CD), and biographical sketches of the pioneers of dynamics and chaos theory. To ensure accessibility to motivated high school students, care has been taken to explain advanced mathematical concepts simply, including exponentials and logarithms, probability, correlation, frequency analysis, fractals, and transfinite numbers. These tools help to resolve the intriguing paradox of motion that is predictable and yet random, while the final chapter explores the various ways chaos theory has been put to practical use.

  5. Simulating intrafraction prostate motion with a random walk model

    Directory of Open Access Journals (Sweden)

    Tobias Pommer, PhD

    2017-07-01

    Conclusions: Random walk modeling is feasible and recreated the characteristics of the observed prostate motion. Introducing artificial transient motion did not improve the overall agreement, although the first 30 seconds of the traces were better reproduced. The model provides a simple estimate of prostate motion during delivery of radiation therapy.

  6. Killing (absorption) versus survival in random motion

    Science.gov (United States)

    Garbaczewski, Piotr

    2017-09-01

    We address diffusion processes in a bounded domain, while focusing on somewhat unexplored affinities between the presence of absorbing and/or inaccessible boundaries. For the Brownian motion (Lévy-stable cases are briefly mentioned) model-independent features are established of the dynamical law that underlies the short-time behavior of these random paths, whose overall lifetime is predefined to be long. As a by-product, the limiting regime of a permanent trapping in a domain is obtained. We demonstrate that the adopted conditioning method, involving the so-called Bernstein transition function, works properly also in an unbounded domain, for stochastic processes with killing (Feynman-Kac kernels play the role of transition densities), provided the spectrum of the related semigroup operator is discrete. The method is shown to be useful in the case, when the spectrum of the generator goes down to zero and no isolated minimal (ground state) eigenvalue is in existence, like in the problem of the long-term survival on a half-line with a sink at origin.

  7. Simulating intrafraction prostate motion with a random walk model.

    Science.gov (United States)

    Pommer, Tobias; Oh, Jung Hun; Munck Af Rosenschöld, Per; Deasy, Joseph O

    2017-01-01

    Prostate motion during radiation therapy (ie, intrafraction motion) can cause unwanted loss of radiation dose to the prostate and increased dose to the surrounding organs at risk. A compact but general statistical description of this motion could be useful for simulation of radiation therapy delivery or margin calculations. We investigated whether prostate motion could be modeled with a random walk model. Prostate motion recorded during 548 radiation therapy fractions in 17 patients was analyzed and used for input in a random walk prostate motion model. The recorded motion was categorized on the basis of whether any transient excursions (ie, rapid prostate motion in the anterior and superior direction followed by a return) occurred in the trace and transient motion. This was separately modeled as a large step in the anterior/superior direction followed by a returning large step. Random walk simulations were conducted with and without added artificial transient motion using either motion data from all observed traces or only traces without transient excursions as model input, respectively. A general estimate of motion was derived with reasonable agreement between simulated and observed traces, especially during the first 5 minutes of the excursion-free simulations. Simulated and observed diffusion coefficients agreed within 0.03, 0.2 and 0.3 mm 2 /min in the left/right, superior/inferior, and anterior/posterior directions, respectively. A rapid increase in variance at the start of observed traces was difficult to reproduce and seemed to represent the patient's need to adjust before treatment. This could be estimated somewhat using artificial transient motion. Random walk modeling is feasible and recreated the characteristics of the observed prostate motion. Introducing artificial transient motion did not improve the overall agreement, although the first 30 seconds of the traces were better reproduced. The model provides a simple estimate of prostate motion during

  8. Localized motion in random matrix decomposition of complex financial systems

    Science.gov (United States)

    Jiang, Xiong-Fei; Zheng, Bo; Ren, Fei; Qiu, Tian

    2017-04-01

    With the random matrix theory, we decompose the multi-dimensional time series of complex financial systems into a set of orthogonal eigenmode functions, which are classified into the market mode, sector mode, and random mode. In particular, the localized motion generated by the business sectors, plays an important role in financial systems. Both the business sectors and their impact on the stock market are identified from the localized motion. We clarify that the localized motion induces different characteristics of the time correlations for the stock-market index and individual stocks. With a variation of a two-factor model, we reproduce the return-volatility correlations of the eigenmodes.

  9. Periodic Boundary Motion in Thermal Turbulence

    International Nuclear Information System (INIS)

    Zhang, Jun; Libchaber, Albert

    2000-01-01

    A free-floating plate is introduced in a Benard convection cell with an open surface. It partially covers the cell and distorts the local heat flux, inducing a coherent flow that in turn moves the plate. Remarkably, the plate can be driven to a periodic motion even under the action of a turbulent fluid. The period of the oscillation depends on the coverage ratio, and on the Rayleigh number of the convective system. The plate oscillatory behavior observed in this experiment may be related to a geological model, in which continents drift in a quasiperiodic fashion. (c) 2000 The American Physical Society

  10. Brownian motion, dynamical randomness and irreversibility

    International Nuclear Information System (INIS)

    Gaspard, Pierre

    2005-01-01

    A relationship giving the entropy production as the difference between a time-reversed entropy per unit time and the standard one is applied to stochastic processes of diffusion of Brownian particles between two reservoirs at different concentrations. The entropy production in the nonequilibrium steady state is interpreted in terms of a time asymmetry in the dynamical randomness between the forward and backward paths of the diffusion process

  11. Circular random motion in diatom gliding under isotropic conditions

    International Nuclear Information System (INIS)

    Gutiérrez-Medina, Braulio; Maldonado, Ana Iris Peña; Guerra, Andrés Jiménez; Rubio, Yadiralia Covarrubias; Meza, Jessica Viridiana García

    2014-01-01

    How cells migrate has been investigated primarily for the case of trajectories composed by joined straight segments. In contrast, little is known when cellular motion follows intrinsically curved paths. Here, we use time-lapse optical microscopy and automated trajectory tracking to investigate how individual cells of the diatom Nitzschia communis glide across surfaces under isotropic environmental conditions. We find a distinct kind of random motion, where trajectories are formed by circular arcs traveled at constant speed, alternated with random stoppages, direction reversals and changes in the orientation of the arcs. Analysis of experimental and computer-simulated trajectories show that the circular random motion of diatom gliding is not optimized for long-distance travel but rather for recurrent coverage of limited surface area. These results suggest that one main biological role for this type of diatom motility is to efficiently build the foundation of algal biofilms. (paper)

  12. Asymptotic properties of a simple random motion

    International Nuclear Information System (INIS)

    Ravishankar, K.

    1988-01-01

    A random walker in R/sup N/ is considered. At each step the walker picks a point in R/sup N/ from a fixed finite set of destination points. Having chosen the point, the walker moves a fraction r (r < 1) of the distance toward the point along a straight line. Assuming that the successive destination points are chosen independently, it is shown that the asymptotic distribution of the walker's position has the same mean as the destination point distribution. An estimate is obtained for the fraction of time the walker stays within a ball centered at the mean value for almost every destination sequence. Examples show that the asymptotic distribution could have intricate structure

  13. Performance characterization of Watson Ahumada motion detector using random dot rotary motion stimuli.

    Directory of Open Access Journals (Sweden)

    Siddharth Jain

    Full Text Available The performance of Watson & Ahumada's model of human visual motion sensing is compared against human psychophysical performance. The stimulus consists of random dots undergoing rotary motion, displayed in a circular annulus. The model matches psychophysical observer performance with respect to most parameters. It is able to replicate some key psychophysical findings such as invariance of observer performance to dot density in the display, and decrease of observer performance with frame duration of the display.Associated with the concept of rotary motion is the notion of a center about which rotation occurs. One might think that for accurate estimation of rotary motion in the display, this center must be accurately known. A simple vector analysis reveals that this need not be the case. Numerical simulations confirm this result, and may explain the position invariance of MST(d cells. Position invariance is the experimental finding that rotary motion sensitive cells are insensitive to where in their receptive field rotation occurs.When all the dots in the display are randomly drawn from a uniform distribution, illusory rotary motion is perceived. This case was investigated by Rose & Blake previously, who termed the illusory rotary motion the omega effect. Two important experimental findings are reported concerning this effect. First, although the display of random dots evokes perception of rotary motion, the direction of motion perceived does not depend on what dot pattern is shown. Second, the time interval between spontaneous flips in perceived direction is lognormally distributed (mode approximately 2 s. These findings suggest the omega effect fits in the category of a typical bistable illusion, and therefore the processes that give rise to this illusion may be the same processes that underlie much of other bistable phenomenon.

  14. Analysis of unbounded operators and random motion

    International Nuclear Information System (INIS)

    Jorgensen, Palle E. T.

    2009-01-01

    We study infinite weighted graphs with view to 'limits at infinity' or boundaries at infinity. Examples of such weighted graphs arise in infinite (in practice, that means 'very' large) networks of resistors or in statistical mechanics models for classical or quantum systems. However, more generally, our analysis includes reproducing kernel Hilbert spaces and associated operators on them. If X is some infinite set of vertices or nodes, in applications the essential ingredient going into the definition is a reproducing kernel Hilbert space; it measures the differences of functions on X evaluated on pairs of points in X. Moreover, the Hilbert norm-squared in H(X) will represent a suitable measure of energy. Associated unbounded operators will define a notion or dissipation, it can be a graph Laplacian or a more abstract unbounded Hermitian operator defined from the reproducing kernel Hilbert space under study. We prove that there are two closed subspaces in reproducing kernel Hilbert space H(X) that measure quantitative notions of limits at infinity in X: one generalizes finite-energy harmonic functions in H(X) and the other a deficiency index of a natural operator in H(X) associated directly with the diffusion. We establish these results in the abstract, and we offer examples and applications. Our results are related to, but different from, potential theoretic notions of 'boundaries' in more standard random walk models. Comparisons are made.

  15. Chaotic motion and random matrix theories

    International Nuclear Information System (INIS)

    Bohigas, O.; Giannoni, M.J.

    1983-01-01

    The authors discussed how to characterize level fluctuations. In full generality, one needs the set of k-level cluster functions Y/sub k/. Some of the most relevant qualitative features of GOE fluctuations have been emphasized: level repulsion (small probability of occurrence of small spacings) and spectral rigidity (for instance, logarithmic increase with L of the variance of the number of levels to be found in an interval of length L). This is in contrast with what happens for a spectrum obtained by adding spacings coming from random independent trials distributed like e/sup - x/, viz.a Poisson spectrum. In this case there is by construction no level repulsion but level clustering (the variance of the number of levels increases linearly with L). The effect of level repulsion is that levels appear rather evenly distributed, and when spectral rigidity is present the spectrum looks incompressible. It is important to notice that the spacing distribution p(x) contains no information about spacing correlations, one of the main characteristics of GOE-fluctuation patterns. The role of exact symmetries is prominent and GOE-predictions apply to levels having the same set of exact quantum number (Jπ)

  16. Diffusion in one dimensional random medium and hyperbolic Brownian motion

    International Nuclear Information System (INIS)

    Comtet, A.; Monthus, C.; Paris-6 Univ., 75

    1995-03-01

    Classical diffusion in a random medium involves an exponential functional of Brownian motion. This functional also appears in the study of Brownian diffusion on a Riemann surface of constant negative curvature. This relationship is analyzed in detail and various distributions are studied using stochastic calculus and functional integration. (author) 17 refs

  17. Random functions via Dyson Brownian Motion: progress and problems

    International Nuclear Information System (INIS)

    Wang, Gaoyuan; Battefeld, Thorsten

    2016-01-01

    We develope a computationally efficient extension of the Dyson Brownian Motion (DBM) algorithm to generate random function in C"2 locally. We further explain that random functions generated via DBM show an unstable growth as the traversed distance increases. This feature restricts the use of such functions considerably if they are to be used to model globally defined ones. The latter is the case if one uses random functions to model landscapes in string theory. We provide a concrete example, based on a simple axionic potential often used in cosmology, to highlight this problem and also offer an ad hoc modification of DBM that suppresses this growth to some degree.

  18. Random functions via Dyson Brownian Motion: progress and problems

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Gaoyuan; Battefeld, Thorsten [Institute for Astrophysics, University of Goettingen,Friedrich Hund Platz 1, D-37077 Goettingen (Germany)

    2016-09-05

    We develope a computationally efficient extension of the Dyson Brownian Motion (DBM) algorithm to generate random function in C{sup 2} locally. We further explain that random functions generated via DBM show an unstable growth as the traversed distance increases. This feature restricts the use of such functions considerably if they are to be used to model globally defined ones. The latter is the case if one uses random functions to model landscapes in string theory. We provide a concrete example, based on a simple axionic potential often used in cosmology, to highlight this problem and also offer an ad hoc modification of DBM that suppresses this growth to some degree.

  19. Random thermal stress in concrete containments

    International Nuclear Information System (INIS)

    Singh, M.P.; Heller, R.A.

    1980-01-01

    Currently, the overly conservative thermal design forces are obtained on the basis of simplified assumptions made about the temperature gradient across the containment wall. Using the method presented in this paper, a more rational and better estimate of the design forces can be obtained. Herein, the outside temperature is considered to consist of a constant mean on which yearly and daily harmonic changes plus a randomly varying part are superimposed. The random part is modeled as a stationary random process. To obtain the stresses due to random and harmonic temperatures, the complex frequency response function approach has been used. Numerical results obtained for a typical containment show that the higher frequency temperature variations, though of large magnitude, induce relatively small forces in a containment. Therefore, in a containment design, a rational separation of more effective, slowly varying temperatures, such as seasonal cycle from less effective but more frequently occuring daily and hourly changes, is desirable to obtain rational design forces. 7 refs

  20. Thermally activated dislocation motion including inertial effects in solid solutions

    International Nuclear Information System (INIS)

    Isaac, R.D.

    1977-01-01

    Dislocation motion through an array of obstacles is considered in terms of the potential energy of the dislocation as it moves through the array. The obstacles form a series of potential wells and barriers which can trap the dislocations. The effect of thermal fluctuations and of a viscous drag on the motion of the dislocation is investigated by analogy with Brownian motion in a field of force. The rate of escape of a trapped dislocation is found to depend on the damping coefficient only for a large viscous drag. The probability that a dislocation will be trapped by a well or barrier is found to depend on the damping coefficient for a small viscous drag. This inertial effect determines how far a dislocation will travel after breaking away from an obstacle

  1. Random forcing of geostrophic motion in rotating stratified turbulence

    Science.gov (United States)

    Waite, Michael L.

    2017-12-01

    Random forcing of geostrophic motion is a common approach in idealized simulations of rotating stratified turbulence. Such forcing represents the injection of energy into large-scale balanced motion, and the resulting breakdown of quasi-geostrophic turbulence into inertia-gravity waves and stratified turbulence can shed light on the turbulent cascade processes of the atmospheric mesoscale. White noise forcing is commonly employed, which excites all frequencies equally, including frequencies much higher than the natural frequencies of large-scale vortices. In this paper, the effects of these high frequencies in the forcing are investigated. Geostrophic motion is randomly forced with red noise over a range of decorrelation time scales τ, from a few time steps to twice the large-scale vortex time scale. It is found that short τ (i.e., nearly white noise) results in about 46% more gravity wave energy than longer τ, despite the fact that waves are not directly forced. We argue that this effect is due to wave-vortex interactions, through which the high frequencies in the forcing are able to excite waves at their natural frequencies. It is concluded that white noise forcing should be avoided, even if it is only applied to the geostrophic motion, when a careful investigation of spontaneous wave generation is needed.

  2. Thermal singularity and droplet motion in one-component fluids on solid substrates with thermal gradients

    KAUST Repository

    Xu, Xinpeng; Qian, Tiezheng

    2012-01-01

    Using a continuum model capable of describing the one-component liquid-gas hydrodynamics down to the contact line scale, we carry out numerical simulation and physical analysis for the droplet motion driven by thermal singularity. For liquid droplets in one-component fluids on heated or cooled substrates, the liquid-gas interface is nearly isothermal. Consequently, a thermal singularity occurs at the contact line and the Marangoni effect due to temperature gradient is suppressed. Through evaporation or condensation in the vicinity of the contact line, the thermal singularity makes the contact angle increase with the increasing substrate temperature. This effect on the contact angle can be used to move the droplets on substrates with thermal gradients. Our numerical results for this kind of droplet motion are explained by a simple fluid dynamical model at the droplet length scale. Since the mechanism for droplet motion is based on the change of contact angle, a separation of length scales is exhibited through a comparison between the droplet motion induced by a wettability gradient and that by a thermal gradient. It is shown that the flow field at the droplet length scale is independent of the statics or dynamics at the contact line scale.

  3. Thermal singularity and droplet motion in one-component fluids on solid substrates with thermal gradients

    KAUST Repository

    Xu, Xinpeng

    2012-06-26

    Using a continuum model capable of describing the one-component liquid-gas hydrodynamics down to the contact line scale, we carry out numerical simulation and physical analysis for the droplet motion driven by thermal singularity. For liquid droplets in one-component fluids on heated or cooled substrates, the liquid-gas interface is nearly isothermal. Consequently, a thermal singularity occurs at the contact line and the Marangoni effect due to temperature gradient is suppressed. Through evaporation or condensation in the vicinity of the contact line, the thermal singularity makes the contact angle increase with the increasing substrate temperature. This effect on the contact angle can be used to move the droplets on substrates with thermal gradients. Our numerical results for this kind of droplet motion are explained by a simple fluid dynamical model at the droplet length scale. Since the mechanism for droplet motion is based on the change of contact angle, a separation of length scales is exhibited through a comparison between the droplet motion induced by a wettability gradient and that by a thermal gradient. It is shown that the flow field at the droplet length scale is independent of the statics or dynamics at the contact line scale.

  4. Disc type thermal actuator with straight beams for angular motion

    International Nuclear Information System (INIS)

    Anwar, M. Arefin; Packirisamy, Muthukumaran; Ahmed, A.K. Waiz

    2013-01-01

    Motion of a micro thermal actuator largely depends on its structural topology. This paper presents designs for a novel rotary type micro thermal actuator. This actuator has unique arrangement of hot segments around the cold segment. Upon application of potential difference, hot segments expand against the cold segment of disc and make the cold disc rotate about its center. This rotary motion can be used for various optical applications like, switching, attenuation and diffraction. The actuator has been fabricated using poly MUMPS process technology. An analytical model was used for predicting steady state temperature profile along the actuator length and rotational behavior of the cold disc under different applied voltages. A finite element analysis (FEA) was carried out to predict the behavior of the actuator by defining an air volume around the structure and also between structure and substrate. Finally testing was done for predicting feasibility of the actuator. Comparison of the rotational behavior obtained from both analytical model and FEA with that of obtained from testing shows close agreement. -- Highlights: ► Electro-thermo-mechanical modeling and verification of rotary micro thermal actuator. ► Modeling with conduction, convection and radiation modes for the air gap below 3 micron. ► In micro level, shape factor and material resistivity were estimated and verified through I–V characteristics. ► Two different designs of different shape factors were designed, fabricated and tested. ► The devices were fabricated using surface micromachining technology and tested for verification

  5. Effects of thermal motion on electromagnetically induced absorption

    International Nuclear Information System (INIS)

    Tilchin, E.; Wilson-Gordon, A. D.; Firstenberg, O.

    2011-01-01

    We describe the effect of thermal motion and buffer-gas collisions on a four-level closed N system interacting with strong pump(s) and a weak probe. This is the simplest system that experiences electromagnetically induced absorption (EIA) due to transfer of coherence via spontaneous emission from the excited state to the ground state. We investigate the influence of Doppler broadening, velocity-changing collisions (VCC), and phase-changing collisions (PCC) with a buffer gas on the EIA spectrum of optically active atoms. In addition to exact expressions, we present an approximate solution for the probe absorption spectrum, which provides physical insight into the behavior of the EIA peak due to VCC, PCC, and the wave-vector difference between the pump and probe beams. VCC are shown to produce a wide pedestal at the base of the EIA peak, which is scarcely affected by the pump-probe angular deviation, whereas the sharp central EIA peak becomes weaker and broader due to the residual Doppler-Dicke effect. Using diffusionlike equations for the atomic coherences and populations, we construct a spatial-frequency filter for a spatially structured probe beam and show that Ramsey narrowing of the EIA peak is obtained for beams of finite width.

  6. Thermal motion of a holographically trapped SPM-like probe

    International Nuclear Information System (INIS)

    Simpson, Stephen H; Hanna, Simon

    2009-01-01

    By holding a complex object in multiple optical traps, it may be harmonically bound with respect to both its position and its orientation. In this way a small probe, or nanotool, can be manipulated in three dimensions and used to measure and apply directed forces, in the manner of a scanning probe microscope. In this paper we evaluate the thermal motion of such a probe held in holographic optical tweezers, by solving the Langevin equation for the general case of a set of spherical vertices linked by cylindrical rods. The concept of a corner frequency, familiar from the case of an optically trapped sphere, is appropriately extended to represent a set of characteristic frequencies given by the eigenvalues of the product of the stiffness matrix and the inverse hydrodynamic resistance matrix of the tool. These eigenvalues may alternatively be interpreted as inverses of a set of characteristic relaxation times for the system. The approach is illustrated by reference to a hypothetical tool consisting of a triangular arrangement of spheres with a lateral probe. The characteristic frequencies and theoretical resolution of the device are derived; variations of these quantities with tool size and orientation and with the optical power distribution, are also considered.

  7. Do Motion Controllers Make Action Video Games Less Sedentary? A Randomized Experiment

    OpenAIRE

    Lyons, Elizabeth J.; Tate, Deborah F.; Ward, Dianne S.; Ribisl, Kurt M.; Bowling, J. Michael; Kalyanaraman, Sriram

    2012-01-01

    Sports- and fitness-themed video games using motion controllers have been found to produce physical activity. It is possible that motion controllers may also enhance energy expenditure when applied to more sedentary games such as action games. Young adults (N = 100) were randomized to play three games using either motion-based or traditional controllers. No main effect was found for controller or game pair (P > .12). An interaction was found such that in one pair, motion control (mean [SD] 0....

  8. AC Own Motion Percentage of Randomly Sampled Cases

    Data.gov (United States)

    Social Security Administration — Longitudinal report detailing the numbers and percentages of Appeals Council (AC) own motion review actions taken on un-appealed favorable hearing level decisions...

  9. Effects of deformability and thermal motion of lipid membrane on electroporation: By molecular dynamics simulations

    KAUST Repository

    Sun, Sheng; Yin, Guangyao; Lee, Yi-Kuen; Wong, Joseph T.Y.; Zhang, Tong-Yi

    2011-01-01

    Effects of mechanical properties and thermal motion of POPE lipid membrane on electroporation were studied by molecular dynamics simulations. Among simulations in which specific atoms of lipids were artificially constrained at their equilibrium

  10. Improving Pulse Rate Measurements during Random Motion Using a Wearable Multichannel Reflectance Photoplethysmograph

    Directory of Open Access Journals (Sweden)

    Kristen M. Warren

    2016-03-01

    Full Text Available Photoplethysmographic (PPG waveforms are used to acquire pulse rate (PR measurements from pulsatile arterial blood volume. PPG waveforms are highly susceptible to motion artifacts (MA, limiting the implementation of PR measurements in mobile physiological monitoring devices. Previous studies have shown that multichannel photoplethysmograms can successfully acquire diverse signal information during simple, repetitive motion, leading to differences in motion tolerance across channels. In this paper, we investigate the performance of a custom-built multichannel forehead-mounted photoplethysmographic sensor under a variety of intense motion artifacts. We introduce an advanced multichannel template-matching algorithm that chooses the channel with the least motion artifact to calculate PR for each time instant. We show that for a wide variety of random motion, channels respond differently to motion artifacts, and the multichannel estimate outperforms single-channel estimates in terms of motion tolerance, signal quality, and PR errors. We have acquired 31 data sets consisting of PPG waveforms corrupted by random motion and show that the accuracy of PR measurements achieved was increased by up to 2.7 bpm when the multichannel-switching algorithm was compared to individual channels. The percentage of PR measurements with error ≤ 5 bpm during motion increased by 18.9% when the multichannel switching algorithm was compared to the mean PR from all channels. Moreover, our algorithm enables automatic selection of the best signal fidelity channel at each time point among the multichannel PPG data.

  11. Unified theory of dislocation motion including thermal activation and inertial effects

    International Nuclear Information System (INIS)

    Isaac, R.D.; Granato, A.V.

    1979-01-01

    Transition-state rate theory has generally been used to explain the temperature dependence of the flow stress of a crystal. However, the existence of a change in the flow stress during the superconducting transition indicates the presence of inertial effects in which dislocations overcome obstacles mechanically rather than thermally. It is shown here that the thermally activated and the inertial overcoming of obstacles are not unrelated but can both be derived from principles of stochastic motion. This leads to a theory of dislocation motion that includes both thermal activation and inertial effects. It is also shown that a distribution of activation energies must be considered to account for the experimental data

  12. Brownian Motion Problem: Random Walk and Beyond -RE ...

    Indian Academy of Sciences (India)

    was subjected to various killing treatments, liquids other .... This phrase is used for the systems rectifying the inescapable thermal noise to produce unidirectional current of particles in the .... with dispersion 2Dt (Figure 2) implying spread of the.

  13. Spherical particle Brownian motion in viscous medium as non-Markovian random process

    International Nuclear Information System (INIS)

    Morozov, Andrey N.; Skripkin, Alexey V.

    2011-01-01

    The Brownian motion of a spherical particle in an infinite medium is described by the conventional methods and integral transforms considering the entrainment of surrounding particles of the medium by the Brownian particle. It is demonstrated that fluctuations of the Brownian particle velocity represent a non-Markovian random process. The features of Brownian motion in short time intervals and in small displacements are considered. -- Highlights: → Description of Brownian motion considering the entrainment of medium is developed. → We find the equations for statistical characteristics of impulse fluctuations. → Brownian motion at small time intervals is considered. → Theoretical results and experimental data are compared.

  14. Investigation of the circular random walk motion in nematic material

    International Nuclear Information System (INIS)

    Bata, L.; Tuettoe, I.

    1976-12-01

    The molecular dynamics of liquid crystalline mesophase is investigated. A new theoretical model describing the rotational motion on a sphere with two relaxation times is worked out. Quasi-elastic neutron spectra have been measured on aligned di-butyl derivative of phenylbenzoyl azoxy-benzoate at different temperatures. The results are interpreted on the basis of the author's model and the non-equivalence of the hydrogen atom is shown. (Sz.N.Z.)

  15. Thermally induced micro-motion by inflection in optical potential

    Czech Academy of Sciences Publication Activity Database

    Šiler, Martin; Jákl, Petr; Brzobohatý, Oto; Ryabov, A.; Filip, R.; Zemánek, Pavel

    2017-01-01

    Roč. 7, MAY (2017), s. 1-8, č. článku 1697. ISSN 2045-2322 R&D Projects: GA ČR GB14-36681G; GA MŠk(CZ) LO1212; GA MŠk ED0017/01/01 Institutional support: RVO:68081731 Keywords : molecular motors * brownian-motion * manipulation * efficiency * tweezers Subject RIV: BH - Optics, Masers, Lasers OBOR OECD: Optics (including laser optics and quantum optics) Impact factor: 4.259, year: 2016

  16. Brownian Motion Problem: Random Walk and Beyond -RE ...

    Indian Academy of Sciences (India)

    by their continuous bombardment by the surrounding molecules of much smaller size (Figure 1). This effect .... of continuous impacts of the randomly moving surround- ing molecules of the fluid (the 'npise'); (ii) these ..... ually increasing range of values due to integration and, thus, keeping it alive. Consequently, the observed ...

  17. Quantal and thermal zero point motion formulae of barrier transmission probability

    International Nuclear Information System (INIS)

    Takigawa, N.; Alhassid, Y.; Balantekin, A.B.

    1992-01-01

    A Green's function method is developed to derive quantal zero point motion formulae for the barrier transmission probability in heavy ion fusion reactions corresponding to various nuclear intrinsic degrees of freedom. In order to apply to the decay of a hot nucleus, the formulae are then generalized to the case where the intrinsic degrees of freedom are in thermal equilibrium with a heat bath. A thermal zero point motion formula for vibrational coupling previously obtained through the use of influence functional methods naturally follows, and the effects of rotational coupling are found to be independent of temperature if the deformation is rigid

  18. THERMAL AND AERODYNAMIC PERFORMANCES OF THE SUPERSONIC MOTION

    Directory of Open Access Journals (Sweden)

    Dejan P Ninković

    2010-01-01

    Full Text Available Generally speaking, Mach number of 4 can be taken as a boundary value for transition from conditions for supersonic, into the area of hypersonic flow, distinguishing two areas: area of supersonic in which the effects of the aerodynamic heating can be neglected and the area of hypersonic, in which the thermal effects become dominant. This paper presents the effects in static and dynamic areas, as well as presentation of G.R.O.M. software for determination of the values of aerodynamic derivatives, which was developed on the basis of linearized theory of supersonic flow. Validation of developed software was carried out through different types of testing, proving its usefulness for engineering practice in the area of supersonic wing aerodynamic loading calculations, even at high Mach numbers, with dominant thermal effects.

  19. Random walk analysis of grain motion during superplastic deformation of TZP

    International Nuclear Information System (INIS)

    Okamoto, T; Yasuda, K; Shiota, T

    2009-01-01

    This study focuses on grain motion in TZP (Tetragonal Zirconia Polycrystal) ceramics during superplastic deformation. The specimen was 16 times elongated repeatedly at 1400 0 C in air. The increment of true plastic strain was set to be 2%, and the specimen was deformed up to 30.3% true plastic strain finally. After each deformation, displacement vectors of specified 748 grains were measured from their position vectors determined by FE-SEM micrographs. As a result, the grains move to the tensile loading direction in zigzag way. And also, the zigzag motion changes with plastic strain: The grains move randomly (random walk motion) by the first 15% true plastic strain, and then grain motion becomes spatially uniform gradually. It is related to changes of constraint of surrounding matrix.

  20. Quantifying the degree of persistence in random amoeboid motion based on the Hurst exponent of fractional Brownian motion.

    Science.gov (United States)

    Makarava, Natallia; Menz, Stephan; Theves, Matthias; Huisinga, Wilhelm; Beta, Carsten; Holschneider, Matthias

    2014-10-01

    Amoebae explore their environment in a random way, unless external cues like, e.g., nutrients, bias their motion. Even in the absence of cues, however, experimental cell tracks show some degree of persistence. In this paper, we analyzed individual cell tracks in the framework of a linear mixed effects model, where each track is modeled by a fractional Brownian motion, i.e., a Gaussian process exhibiting a long-term correlation structure superposed on a linear trend. The degree of persistence was quantified by the Hurst exponent of fractional Brownian motion. Our analysis of experimental cell tracks of the amoeba Dictyostelium discoideum showed a persistent movement for the majority of tracks. Employing a sliding window approach, we estimated the variations of the Hurst exponent over time, which allowed us to identify points in time, where the correlation structure was distorted ("outliers"). Coarse graining of track data via down-sampling allowed us to identify the dependence of persistence on the spatial scale. While one would expect the (mode of the) Hurst exponent to be constant on different temporal scales due to the self-similarity property of fractional Brownian motion, we observed a trend towards stronger persistence for the down-sampled cell tracks indicating stronger persistence on larger time scales.

  1. Catalytic micromotor generating self-propelled regular motion through random fluctuation

    Science.gov (United States)

    Yamamoto, Daigo; Mukai, Atsushi; Okita, Naoaki; Yoshikawa, Kenichi; Shioi, Akihisa

    2013-07-01

    Most of the current studies on nano/microscale motors to generate regular motion have adapted the strategy to fabricate a composite with different materials. In this paper, we report that a simple object solely made of platinum generates regular motion driven by a catalytic chemical reaction with hydrogen peroxide. Depending on the morphological symmetry of the catalytic particles, a rich variety of random and regular motions are observed. The experimental trend is well reproduced by a simple theoretical model by taking into account of the anisotropic viscous effect on the self-propelled active Brownian fluctuation.

  2. Novel Thermal Analysis Model of the Foot-Shoe Sole Interface during Gait Motion

    Directory of Open Access Journals (Sweden)

    Yasuhiro Shimazaki

    2018-02-01

    Full Text Available Excessive heat at the foot-shoe sole interface negatively affects a human’s thermal comfort. An understanding of the thermal behavior at this interface is important for alleviating this discomfort. During gait motion, a human’s body weight cyclically compresses a shoe sole (commonly constructed of viscoelastic materials, generating heat during loading. To evaluate the thermal effects of this internal heat generation on foot comfort, we developed and empirically validated a thermal analysis model during gait motion. A simple, one-dimensional prediction model for heat conduction with heat generation during compressive loading was used. Heat generation was estimated as a function of the shoe sole’s material properties (e.g., elastic modulus and various gait parameters. When compared with experimental results, the proposed model proved effective in predicting thermal behavior at the foot-shoe sole interface under various conditions and shows potential for improving a human’s thermal comfort during gait motion through informed footwear design.

  3. Neutron moderation theory with thermal motion of the moderator nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Rusov, V.D.; Tarasov, V.A.; Chernezhenko, S.A.; Kakaev, A.A.; Smolyar, V.P. [Odessa National Polytechnic University, Department of Theoretical and Experimental Nuclear Physics, Odessa (Ukraine)

    2017-09-15

    In this paper we present the analytical expression for the neutron scattering law for an isotropic source of neutrons, obtained within the framework of the gas model with the temperature of the moderating medium as a parameter. The obtained scattering law is based on the solution of the general kinematic problem of elastic scattering of neutrons on nuclei in the L-system. Both the neutron and the nucleus possess arbitrary velocities in the L-system. For the new scattering law we obtain the flux densities and neutron moderation spectra as functions of temperature for the reactor fissile medium. The expressions for the moderating neutrons spectra allow reinterpreting the physical nature of the underlying processes in the thermal region. (orig.)

  4. Scale-free animal movement patterns: Levy walks outperform fractional Brownian motions and fractional Levy motions in random search scenarios

    International Nuclear Information System (INIS)

    Reynolds, A M

    2009-01-01

    The movement patterns of a diverse range of animals have scale-free characteristics. These characteristics provide necessary but not sufficient conditions for the presence of movement patterns that can be approximated by Levy walks. Nevertheless, it has been widely assumed that the occurrence of scale-free animal movements can indeed be attributed to the presence of Levy walks. This is, in part, because it is known that the super-diffusive properties of Levy walks can be advantageous in random search scenarios when searchers have little or no prior knowledge of target locations. However, fractional Brownian motions (fBms) and fractional Levy motions (fLms) are both scale-free and super-diffusive, and so it is possible that these motions rather than Levy walks underlie some or all occurrences of scale-free animal movement patterns. Here this possibility is examined in numerical simulations through a determination of the searching efficiencies of fBm and fLm searches. It is shown that these searches are less efficient than Levy walk searches. This finding does not rule out the possibility that some animals with scale-free movement patterns are executing fBm and fLm searches, but it does make Levy walk searches the more likely possibility.

  5. The colour of thermal noise in classical Brownian motion: a feasibility study of direct experimental observation

    International Nuclear Information System (INIS)

    Berg-Soerensen, Kirstine; Flyvbjerg, Henrik

    2005-01-01

    One hundred years after Einstein modelled Brownian motion, a central aspect of this motion in incompressible fluids has not been verified experimentally: the thermal noise that drives the Brownian particle, is not white, as in Einstein's simple theory. It is slightly coloured, due to hydrodynamics and the fluctuation-dissipation theorem. This theoretical result from the 1970s was prompted by computer simulation results in apparent violation of Einstein's theory. We discuss how a direct experimental observation of this colour might be carried out by using optical tweezers to separate the thermal noise from the particle's dynamic response to it. Since the thermal noise is almost white, very good statistics is necessary to resolve its colour. That requires stable equipment and long recording times, possibly making this experiment one for the future only. We give results for experimental requirements and for stochastic errors as functions of experimental window and measurement time, and discuss some potential sources of systematic errors

  6. A Novel Motion Compensation Method for Random Stepped Frequency Radar with M-sequence

    Science.gov (United States)

    Liao, Zhikun; Hu, Jiemin; Lu, Dawei; Zhang, Jun

    2018-01-01

    The random stepped frequency radar is a new kind of synthetic wideband radar. In the research, it has been found that it possesses a thumbtack-like ambiguity function which is considered to be the ideal one. This also means that only a precise motion compensation could result in the correct high resolution range profile. In this paper, we will introduce the random stepped frequency radar coded by M-sequence firstly and briefly analyse the effect of relative motion between target and radar on the distance imaging, which is called defocusing problem. Then, a novel motion compensation method, named complementary code cancellation, will be put forward to solve this problem. Finally, the simulated experiments will demonstrate its validity and the computational analysis will show up its efficiency.

  7. An Interactive Computer Model for Improved Student Understanding of Random Particle Motion and Osmosis

    Science.gov (United States)

    Kottonau, Johannes

    2011-01-01

    Effectively teaching the concepts of osmosis to college-level students is a major obstacle in biological education. Therefore, a novel computer model is presented that allows students to observe the random nature of particle motion simultaneously with the seemingly directed net flow of water across a semipermeable membrane during osmotic…

  8. Similarity and number of alternatives in the random-dot motion paradigm

    NARCIS (Netherlands)

    van Maanen, L.; Grasman, R.P.P.P.; Forstmann, B.U.; Keuken, M.C.; Brown, S.D.; Wagenmakers, E.-J.

    2012-01-01

    The popular random-dot motion (RDM) task has recently been applied to multiple-choice perceptual decisionmaking. However, changes in the number of alternatives on an RDM display lead to changes in the similarity between the alternatives, complicating the study of multiple-choice effects. To

  9. Vestibular Stimulation for ADHD: Randomized Controlled Trial of Comprehensive Motion Apparatus

    Science.gov (United States)

    Clark, David L.; Arnold, L. Eugene; Crowl, Lindsay; Bozzolo, Hernan; Peruggia, Mario; Ramadan, Yaser; Bornstein, Robert; Hollway, Jill A.; Thompson, Susan; Malone, Krista; Hall, Kristy L.; Shelton, Sara B.; Bozzolo, Dawn R.; Cook, Amy

    2008-01-01

    Objective: This research evaluates effects of vestibular stimulation by Comprehensive Motion Apparatus (CMA) in ADHD. Method: Children ages 6 to 12 (48 boys, 5 girls) with ADHD were randomized to thrice-weekly 30-min treatments for 12 weeks with CMA, stimulating otoliths and semicircular canals, or a single-blind control of equal duration and…

  10. Random walks, Brownian motion, and interacting particle systems: a festschrift in honor of Frank Spitzer

    National Research Council Canada - National Science Library

    Durrett, Richard; Kesten, Harry; Spitzer, Frank

    1991-01-01

    ..., made the transparency used in the printing process. STUDENTS OF FRANK SPITZERSTUDENTS OF FRANK SPITZER 1957 J. W. Lamperti, On the asymptotic behavior of recurrent and almostrecurrent events. 1964 W. W. Whitman, Some strong laws for random walks and Brownian motion. 1965 J. C. Mineka, The existence and uniqueness of positive solutions to the Wien...

  11. Effects of deformability and thermal motion of lipid membrane on electroporation: By molecular dynamics simulations

    International Nuclear Information System (INIS)

    Sun, Sheng; Yin, Guangyao; Lee, Yi-Kuen; Wong, Joseph T.Y.; Zhang, Tong-Yi

    2011-01-01

    Research highlights: → MD simulations show that deformability and thermal motion of membrane affect electroporation. → Stiffer membrane inhibits electroporation and makes water penetrate from both sides. → Higher temperature accelerates electroporation. -- Abstract: Effects of mechanical properties and thermal motion of POPE lipid membrane on electroporation were studied by molecular dynamics simulations. Among simulations in which specific atoms of lipids were artificially constrained at their equilibrium positions using a spring with force constant of 2.0 kcal/(mol A 2 ) in the external electric field of 1.4 kcal/(mol A e), only constraint on lateral motions of lipid tails prohibited electroporation while non-tail parts had little effects. When force constant decreased to 0.2 kcal/(mol A 2 ) in the position constraints on lipid tails in the external electric field of 2.0 kcal/(mol A e), water molecules began to enter the membrane. Position constraints of lipid tails allow water to penetrate from both sides of membrane. Thermal motion of lipids can induce initial defects in the hydrophobic core of membrane, which are favorable nucleation sites for electroporation. Simulations at different temperatures revealed that as the temperature increases, the time taken to the initial pore formation will decrease.

  12. Intra-fraction motion of the prostate is a random walk

    Science.gov (United States)

    Ballhausen, H.; Li, M.; Hegemann, N.-S.; Ganswindt, U.; Belka, C.

    2015-01-01

    A random walk model for intra-fraction motion has been proposed, where at each step the prostate moves a small amount from its current position in a random direction. Online tracking data from perineal ultrasound is used to validate or reject this model against alternatives. Intra-fraction motion of a prostate was recorded by 4D ultrasound (Elekta Clarity system) during 84 fractions of external beam radiotherapy of six patients. In total, the center of the prostate was tracked for 8 h in intervals of 4 s. Maximum likelihood model parameters were fitted to the data. The null hypothesis of a random walk was tested with the Dickey-Fuller test. The null hypothesis of stationarity was tested by the Kwiatkowski-Phillips-Schmidt-Shin test. The increase of variance in prostate position over time and the variability in motility between fractions were analyzed. Intra-fraction motion of the prostate was best described as a stochastic process with an auto-correlation coefficient of ρ = 0.92  ±  0.13. The random walk hypothesis (ρ = 1) could not be rejected (p = 0.27). The static noise hypothesis (ρ = 0) was rejected (p test rejected the null hypothesis ρ = 1 in 25% to 32% of cases. On average, the Kwiatkowski-Phillips-Schmidt-Shin test rejected the null hypothesis ρ = 0 with a probability of 93% to 96%. The variance in prostate position increased linearly over time (r2 = 0.9  ±  0.1). Variance kept increasing and did not settle at a maximum as would be expected from a stationary process. There was substantial variability in motility between fractions and patients with maximum aberrations from isocenter ranging from 0.5 mm to over 10 mm in one patient alone. In conclusion, evidence strongly suggests that intra-fraction motion of the prostate is a random walk and neither static (like inter-fraction setup errors) nor stationary (like a cyclic motion such as breathing, for example). The prostate tends to drift away from the isocenter during a fraction, and

  13. Intra-fraction motion of the prostate is a random walk

    International Nuclear Information System (INIS)

    Ballhausen, H; Li, M; Hegemann, N-S; Ganswindt, U; Belka, C

    2015-01-01

    A random walk model for intra-fraction motion has been proposed, where at each step the prostate moves a small amount from its current position in a random direction. Online tracking data from perineal ultrasound is used to validate or reject this model against alternatives. Intra-fraction motion of a prostate was recorded by 4D ultrasound (Elekta Clarity system) during 84 fractions of external beam radiotherapy of six patients. In total, the center of the prostate was tracked for 8 h in intervals of 4 s. Maximum likelihood model parameters were fitted to the data. The null hypothesis of a random walk was tested with the Dickey–Fuller test. The null hypothesis of stationarity was tested by the Kwiatkowski–Phillips–Schmidt–Shin test. The increase of variance in prostate position over time and the variability in motility between fractions were analyzed. Intra-fraction motion of the prostate was best described as a stochastic process with an auto-correlation coefficient of ρ = 0.92  ±  0.13. The random walk hypothesis (ρ = 1) could not be rejected (p = 0.27). The static noise hypothesis (ρ = 0) was rejected (p < 0.001). The Dickey–Fuller test rejected the null hypothesis ρ = 1 in 25% to 32% of cases. On average, the Kwiatkowski–Phillips–Schmidt–Shin test rejected the null hypothesis ρ = 0 with a probability of 93% to 96%. The variance in prostate position increased linearly over time (r 2 = 0.9  ±  0.1). Variance kept increasing and did not settle at a maximum as would be expected from a stationary process. There was substantial variability in motility between fractions and patients with maximum aberrations from isocenter ranging from 0.5 mm to over 10 mm in one patient alone. In conclusion, evidence strongly suggests that intra-fraction motion of the prostate is a random walk and neither static (like inter-fraction setup errors) nor stationary (like a cyclic motion such as breathing, for example). The prostate tends to

  14. Thermally Activated Motion of Sodium Cations in Insulating Parent Low-Silica X Zeolite

    Science.gov (United States)

    Igarashi, Mutsuo; Jeglič, Peter; Mežnaršič, Tadej; Nakano, Takehito; Nozue, Yasuo; Watanabe, Naohiro; Arčon, Denis

    2017-07-01

    We report a 23Na spin-lattice relaxation rate, T1 - 1, in low-silica X zeolite. T1 - 1 follows multiple BPP-type behavior as a result of thermal motion of sodium cations in insulating material. The estimated lowest activation energy of 15 meV is much lower than 100 meV observed previously for sodium motion in heavily Na-loaded samples and is most likely attributed to short-distance jumps of sodium cations between sites within the same supercage.

  15. See-saw motion of thermal boundary layer under vibrations: An implication of forced piston effect

    Science.gov (United States)

    Sharma, D.; Erriguible, A.; Amiroudine, S.

    2017-12-01

    The phenomenon of piston effect is well known in supercritical fluids wherein the thermal homogenization of the bulk occurs on a very short time scale due to pressure change caused by expansion or contraction of the fluid in the thermal boundary layer. In this article, we highlight an interesting phenomenon wherein by the application of external forces (vibration) normal to the temperature gradient, see-saw motion of the thermal boundary layer is observed in weightlessness conditions. This is attributed to the thermomechanical coupling caused by the temperature change due to external forces. We term this change in the temperature field due to external forces as forced piston effect (FPE). A detailed investigation of this intriguing behavior shows that the see-saw motion is attributed to the variation of the relative thickness of the thermal boundary layer, defined on the basis of relative local bulk temperature, along the direction of vibration. This change in the temperature field, which is observed to be caused by FPE in vibration, is shown to depend on the compressibility (and thus proximity to the critical point), the imposed acceleration and the cell size. It is also found that see-saw motion persists in the presence of gravity and thus is described ubiquitous in nature for all conditions. A plot illustrating the maximum change in the temperature as a function of these parameters is further proposed.

  16. Inertial-particle dynamics in turbulent flows: caustics, concentration fluctuations and random uncorrelated motion

    International Nuclear Information System (INIS)

    Gustavsson, K; Mehlig, B; Meneguz, E; Reeks, M

    2012-01-01

    We have performed numerical simulations of inertial particles in random model flows in the white-noise limit (at zero Kubo number, Ku = 0) and at finite Kubo numbers. Our results for the moments of relative inertial-particle velocities are in good agreement with recent theoretical results (Gustavsson and Mehlig 2011a) based on the formation of phase-space singularities in the inertial-particle dynamics (caustics). We discuss the relation between three recent approaches describing the dynamics and spatial distribution of inertial particles suspended in turbulent flows: caustic formation, real-space singularities of the deformation tensor and random uncorrelated motion. We discuss how the phase- and real-space singularities are related. Their formation is well understood in terms of a local theory. We summarise the implications for random uncorrelated motion. (paper)

  17. Nonisothermal Brownian motion: Thermophoresis as the macroscopic manifestation of thermally biased molecular motion.

    Science.gov (United States)

    Brenner, Howard

    2005-12-01

    of the light gas's drift velocity, to each be identified with the Chapman-Enskog "thermal diffusion velocity" of the quasi-Lorentzian gas, here designated by the symbol UM/M, as calculated by de la Mora and Mercer. It is further pointed out that, modulo the collective uncertainties cited above, the common velocities UD,U, and UM/M are identical to the single-component gas's diffuse volume current jv, the latter representing yet another, independent, strictly continuum-mechanical concept. Finally, comments are offered on the extension of the single-component drift velocity notion to liquids, and its application towards rationalizing Soret thermal-diffusion separation phenomena in quasi-Lorentzian liquid-phase binary mixtures composed of disparately sized solute and solvent molecules, with the massive Brownian solute molecules (e.g., colloidal particles) present in disproportionately small amounts relative to that of the solvent.

  18. Integration of motion energy from overlapping random background noise increases perceived speed of coherently moving stimuli.

    Science.gov (United States)

    Chuang, Jason; Ausloos, Emily C; Schwebach, Courtney A; Huang, Xin

    2016-12-01

    The perception of visual motion can be profoundly influenced by visual context. To gain insight into how the visual system represents motion speed, we investigated how a background stimulus that did not move in a net direction influenced the perceived speed of a center stimulus. Visual stimuli were two overlapping random-dot patterns. The center stimulus moved coherently in a fixed direction, whereas the background stimulus moved randomly. We found that human subjects perceived the speed of the center stimulus to be significantly faster than its veridical speed when the background contained motion noise. Interestingly, the perceived speed was tuned to the noise level of the background. When the speed of the center stimulus was low, the highest perceived speed was reached when the background had a low level of motion noise. As the center speed increased, the peak perceived speed was reached at a progressively higher background noise level. The effect of speed overestimation required the center stimulus to overlap with the background. Increasing the background size within a certain range enhanced the effect, suggesting spatial integration. The speed overestimation was significantly reduced or abolished when the center stimulus and the background stimulus had different colors, or when they were placed at different depths. When the center- and background-stimuli were perceptually separable, speed overestimation was correlated with perceptual similarity between the center- and background-stimuli. These results suggest that integration of motion energy from random motion noise has a significant impact on speed perception. Our findings put new constraints on models regarding the neural basis of speed perception. Copyright © 2016 the American Physiological Society.

  19. Brownian motion properties of optoelectronic random bit generators based on laser chaos.

    Science.gov (United States)

    Li, Pu; Yi, Xiaogang; Liu, Xianglian; Wang, Yuncai; Wang, Yongge

    2016-07-11

    The nondeterministic property of the optoelectronic random bit generator (RBG) based on laser chaos are experimentally analyzed from two aspects of the central limit theorem and law of iterated logarithm. The random bits are extracted from an optical feedback chaotic laser diode using a multi-bit extraction technique in the electrical domain. Our experimental results demonstrate that the generated random bits have no statistical distance from the Brownian motion, besides that they can pass the state-of-the-art industry-benchmark statistical test suite (NIST SP800-22). All of them give a mathematically provable evidence that the ultrafast random bit generator based on laser chaos can be used as a nondeterministic random bit source.

  20. Wetting and motion behaviors of water droplet on graphene under thermal-electric coupling field

    Science.gov (United States)

    Zhang, Zhong-Qiang; Dong, Xin; Ye, Hong-Fei; Cheng, Guang-Gui; Ding, Jian-Ning; Ling, Zhi-Yong

    2015-02-01

    Wetting dynamics and motion behaviors of a water droplet on graphene are characterized under the electric-thermal coupling field using classical molecular dynamics simulation method. The water droplet on graphene can be driven by the temperature gradient, while the moving direction is dependent on the electric field intensity. Concretely, the water droplet on graphene moves from the low temperature region to the high temperature region for the relatively weak electric field intensity. The motion acceleration increases with the electric field intensity on graphene, whereas the moving direction switches when the electric field intensity increases up to a threshold. The essence is the change from hydrophilic to hydrophobic for the water droplet on graphene at a threshold of the electric field intensity. Moreover, the driven force of the water droplet caused by the overall oscillation of graphene has important influence on the motion behaviors. The results are helpful to control the wettability of graphene and further develop the graphene-based fluidic nanodevices.

  1. Thermal fluctuations in resonant motion of fluxons on a Josephson transmission line: Theory and experiment

    DEFF Research Database (Denmark)

    Jørgensen, E.; Koshelets, V. P.; Monaco, Roberto

    1982-01-01

    The radiation emission from long and narrow Josephson tunnel junctions dc-current biased on zero-field steps has been ascribed to resonant motion of fluxons on the transmission line. Within this dynamic model a theoretical expression for the radiation linewidth is derived from a full statistical ...... treatment of thermal fluctuations in the fluxon velocity. The result appears to be very general and is corroborated by experimental determination of linewidth and frequency of radiation emitted from overlap Nb-I-Pb junctions....

  2. Instanton Approach to the Langevin Motion of a Particle in a Random Potential

    International Nuclear Information System (INIS)

    Lopatin, A. V.; Vinokur, V. M.

    2001-01-01

    We develop an instanton approach to the nonequilibrium dynamics in one-dimensional random environments. The long time behavior is controlled by rare fluctuations of the disorder potential and, accordingly, by the tail of the distribution function for the time a particle needs to propagate along the system (the delay time). The proposed method allows us to find the tail of the delay time distribution function and delay time moments, providing thus an exact description of the long time dynamics. We analyze arbitrary environments covering different types of glassy dynamics: dynamics in a short-range random field, creep, and Sinai's motion

  3. Do Motion Controllers Make Action Video Games Less Sedentary? A Randomized Experiment

    Science.gov (United States)

    Lyons, Elizabeth J.; Tate, Deborah F.; Ward, Dianne S.; Ribisl, Kurt M.; Bowling, J. Michael; Kalyanaraman, Sriram

    2012-01-01

    Sports- and fitness-themed video games using motion controllers have been found to produce physical activity. It is possible that motion controllers may also enhance energy expenditure when applied to more sedentary games such as action games. Young adults (N = 100) were randomized to play three games using either motion-based or traditional controllers. No main effect was found for controller or game pair (P > .12). An interaction was found such that in one pair, motion control (mean [SD] 0.96 [0.20] kcal · kg−1 · hr−1) produced 0.10 kcal · kg−1 · hr−1 (95% confidence interval 0.03 to 0.17) greater energy expenditure than traditional control (0.86 [0.17] kcal · kg−1 · hr−1, P = .048). All games were sedentary. As currently implemented, motion control is unlikely to produce moderate intensity physical activity in action games. However, some games produce small but significant increases in energy expenditure, which may benefit health by decreasing sedentary behavior. PMID:22028959

  4. Do Motion Controllers Make Action Video Games Less Sedentary? A Randomized Experiment

    Directory of Open Access Journals (Sweden)

    Elizabeth J. Lyons

    2012-01-01

    Full Text Available Sports- and fitness-themed video games using motion controllers have been found to produce physical activity. It is possible that motion controllers may also enhance energy expenditure when applied to more sedentary games such as action games. Young adults (N = 100 were randomized to play three games using either motion-based or traditional controllers. No main effect was found for controller or game pair (P > .12. An interaction was found such that in one pair, motion control (mean [SD] 0.96 [0.20] kcal ⋅ kg-1 ⋅ hr-1 produced 0.10 kcal ⋅ kg-1 ⋅ hr-1 (95% confidence interval 0.03 to 0.17 greater energy expenditure than traditional control (0.86 [0.17] kcal ⋅ kg-1 ⋅ hr-1, P = .048. All games were sedentary. As currently implemented, motion control is unlikely to produce moderate intensity physical activity in action games. However, some games produce small but significant increases in energy expenditure, which may benefit health by decreasing sedentary behavior.

  5. Do motion controllers make action video games less sedentary? A randomized experiment.

    Science.gov (United States)

    Lyons, Elizabeth J; Tate, Deborah F; Ward, Dianne S; Ribisl, Kurt M; Bowling, J Michael; Kalyanaraman, Sriram

    2012-01-01

    Sports- and fitness-themed video games using motion controllers have been found to produce physical activity. It is possible that motion controllers may also enhance energy expenditure when applied to more sedentary games such as action games. Young adults (N = 100) were randomized to play three games using either motion-based or traditional controllers. No main effect was found for controller or game pair (P > .12). An interaction was found such that in one pair, motion control (mean [SD] 0.96 [0.20] kcal · kg(-1) · hr(-1)) produced 0.10 kcal · kg(-1) · hr(-1) (95% confidence interval 0.03 to 0.17) greater energy expenditure than traditional control (0.86 [0.17] kcal · kg(-1) · hr(-1), P = .048). All games were sedentary. As currently implemented, motion control is unlikely to produce moderate intensity physical activity in action games. However, some games produce small but significant increases in energy expenditure, which may benefit health by decreasing sedentary behavior.

  6. Molecular dynamics simulations for the motion of evaporative droplets driven by thermal gradients along nanochannels

    KAUST Repository

    Wu, Congmin

    2013-04-04

    For a one-component fluid on a solid substrate, a thermal singularity may occur at the contact line where the liquid-vapor interface intersects the solid surface. Physically, the liquid-vapor interface is almost isothermal at the liquid-vapor coexistence temperature in one-component fluids while the solid surface is almost isothermal for solids of high thermal conductivity. Therefore, a temperature discontinuity is formed if the two isothermal interfaces are of different temperatures and intersect at the contact line. This leads to the so-called thermal singularity. The localized hydrodynamics involving evaporation/condensation near the contact line leads to a contact angle depending on the underlying substrate temperature. This dependence has been shown to lead to the motion of liquid droplets on solid substrates with thermal gradients (Xu and Qian 2012 Phys. Rev. E 85 061603). In the present work, we carry out molecular dynamics (MD) simulations as numerical experiments to further confirm the predictions made from our previous continuum hydrodynamic modeling and simulations, which are actually semi-quantitatively accurate down to the small length scales in the problem. Using MD simulations, we investigate the motion of evaporative droplets in one-component Lennard-Jones fluids confined in nanochannels with thermal gradients. The droplet is found to migrate in the direction of decreasing temperature of solid walls, with a migration velocity linearly proportional to the temperature gradient. This agrees with the prediction of our continuum model. We then measure the effect of droplet size on the droplet motion. It is found that the droplet mobility is inversely proportional to a dimensionless coefficient associated with the total rate of dissipation due to droplet movement. Our results show that this coefficient is of order unity and increases with the droplet size for the small droplets (∼10 nm) simulated in the present work. These findings are in semi

  7. Sensitivity of neurons in the middle temporal area of marmoset monkeys to random dot motion.

    Science.gov (United States)

    Chaplin, Tristan A; Allitt, Benjamin J; Hagan, Maureen A; Price, Nicholas S C; Rajan, Ramesh; Rosa, Marcello G P; Lui, Leo L

    2017-09-01

    Neurons in the middle temporal area (MT) of the primate cerebral cortex respond to moving visual stimuli. The sensitivity of MT neurons to motion signals can be characterized by using random-dot stimuli, in which the strength of the motion signal is manipulated by adding different levels of noise (elements that move in random directions). In macaques, this has allowed the calculation of "neurometric" thresholds. We characterized the responses of MT neurons in sufentanil/nitrous oxide-anesthetized marmoset monkeys, a species that has attracted considerable recent interest as an animal model for vision research. We found that MT neurons show a wide range of neurometric thresholds and that the responses of the most sensitive neurons could account for the behavioral performance of macaques and humans. We also investigated factors that contributed to the wide range of observed thresholds. The difference in firing rate between responses to motion in the preferred and null directions was the most effective predictor of neurometric threshold, whereas the direction tuning bandwidth had no correlation with the threshold. We also showed that it is possible to obtain reliable estimates of neurometric thresholds using stimuli that were not highly optimized for each neuron, as is often necessary when recording from large populations of neurons with different receptive field concurrently, as was the case in this study. These results demonstrate that marmoset MT shows an essential physiological similarity to macaque MT and suggest that its neurons are capable of representing motion signals that allow for comparable motion-in-noise judgments. NEW & NOTEWORTHY We report the activity of neurons in marmoset MT in response to random-dot motion stimuli of varying coherence. The information carried by individual MT neurons was comparable to that of the macaque, and the maximum firing rates were a strong predictor of sensitivity. Our study provides key information regarding the neural

  8. Effects of deformability and thermal motion of lipid membrane on electroporation: By molecular dynamics simulations

    KAUST Repository

    Sun, Sheng

    2011-01-01

    Effects of mechanical properties and thermal motion of POPE lipid membrane on electroporation were studied by molecular dynamics simulations. Among simulations in which specific atoms of lipids were artificially constrained at their equilibrium positions using a spring with force constant of 2.0kcal/(molÅ2) in the external electric field of 1.4kcal/(molÅe), only constraint on lateral motions of lipid tails prohibited electroporation while non-tail parts had little effects. When force constant decreased to 0.2kcal/(molÅ2) in the position constraints on lipid tails in the external electric field of 2.0kcal/(molÅe), water molecules began to enter the membrane. Position constraints of lipid tails allow water to penetrate from both sides of membrane. Thermal motion of lipids can induce initial defects in the hydrophobic core of membrane, which are favorable nucleation sites for electroporation. Simulations at different temperatures revealed that as the temperature increases, the time taken to the initial pore formation will decrease. © 2010 Elsevier Inc.

  9. Thermally induced motion of marine sediments resulting from disposal of radioactive wastes

    International Nuclear Information System (INIS)

    Chavez, P.F.; Dawson, P.R.

    1981-01-01

    Coupled creep and heat transfer calculations have been performed to assess the sensitivity of heat load, viscosity, and canister density on the motion of waste canisters buried in marine sediments. Results indicate that no upward movement is predicted for heat loads remaining within the metallurgical and geochemical constraints placed on the temperature of sediments near the canister for the times analyzed. Upward movement of the canister is again not observed in calculations involving reasonable variations of the sediment viscosity and canister density. Maximum effective deviatoric stress levels due to thermally induced differential body forces are significantly less than the sediment's short term peak strength

  10. Review of the nuclear reactor thermal hydraulic research in ocean motions

    International Nuclear Information System (INIS)

    Yan, B.H.

    2017-01-01

    The research and development of small modular reactor in floating platform has been strongly supported by Chinese government and enterprises. Due to the effect of ocean waves, the thermal hydraulic behavior and safety characteristics of floating reactor are different from that of land-based reactor. Many scholars including the author have published their research and results in open literatures. Much of these literatures are valuable but there are also some contradictory conclusions. In this wok, the nuclear reactor thermal hydraulic research in ocean motions was systematically summarized. Valuable results and experimental data were analyzed and classified. Inherent mechanism for controversial issues in different experiments was explained. Necessary work needed in the future was suggested. Through this work, we attempt to find as many valuable results as possible for the designing and subsequent research.

  11. Review of the nuclear reactor thermal hydraulic research in ocean motions

    Energy Technology Data Exchange (ETDEWEB)

    Yan, B.H., E-mail: yanbh3@mail.sysu.edu.cn

    2017-03-15

    The research and development of small modular reactor in floating platform has been strongly supported by Chinese government and enterprises. Due to the effect of ocean waves, the thermal hydraulic behavior and safety characteristics of floating reactor are different from that of land-based reactor. Many scholars including the author have published their research and results in open literatures. Much of these literatures are valuable but there are also some contradictory conclusions. In this wok, the nuclear reactor thermal hydraulic research in ocean motions was systematically summarized. Valuable results and experimental data were analyzed and classified. Inherent mechanism for controversial issues in different experiments was explained. Necessary work needed in the future was suggested. Through this work, we attempt to find as many valuable results as possible for the designing and subsequent research.

  12. Thermal motion in proteins: Large effects on the time-averaged interaction energies

    International Nuclear Information System (INIS)

    Goethe, Martin; Rubi, J. Miguel; Fita, Ignacio

    2016-01-01

    As a consequence of thermal motion, inter-atomic distances in proteins fluctuate strongly around their average values, and hence, also interaction energies (i.e. the pair-potentials evaluated at the fluctuating distances) are not constant in time but exhibit pronounced fluctuations. These fluctuations cause that time-averaged interaction energies do generally not coincide with the energy values obtained by evaluating the pair-potentials at the average distances. More precisely, time-averaged interaction energies behave typically smoother in terms of the average distance than the corresponding pair-potentials. This averaging effect is referred to as the thermal smoothing effect. Here, we estimate the strength of the thermal smoothing effect on the Lennard-Jones pair-potential for globular proteins at ambient conditions using x-ray diffraction and simulation data of a representative set of proteins. For specific atom species, we find a significant smoothing effect where the time-averaged interaction energy of a single atom pair can differ by various tens of cal/mol from the Lennard-Jones potential at the average distance. Importantly, we observe a dependency of the effect on the local environment of the involved atoms. The effect is typically weaker for bulky backbone atoms in beta sheets than for side-chain atoms belonging to other secondary structure on the surface of the protein. The results of this work have important practical implications for protein software relying on free energy expressions. We show that the accuracy of free energy expressions can largely be increased by introducing environment specific Lennard-Jones parameters accounting for the fact that the typical thermal motion of protein atoms depends strongly on their local environment.

  13. Thermal motion in proteins: Large effects on the time-averaged interaction energies

    Energy Technology Data Exchange (ETDEWEB)

    Goethe, Martin, E-mail: martingoethe@ub.edu; Rubi, J. Miguel [Departament de Física Fonamental, Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona (Spain); Fita, Ignacio [Institut de Biologia Molecular de Barcelona, Baldiri Reixac 10, 08028 Barcelona (Spain)

    2016-03-15

    As a consequence of thermal motion, inter-atomic distances in proteins fluctuate strongly around their average values, and hence, also interaction energies (i.e. the pair-potentials evaluated at the fluctuating distances) are not constant in time but exhibit pronounced fluctuations. These fluctuations cause that time-averaged interaction energies do generally not coincide with the energy values obtained by evaluating the pair-potentials at the average distances. More precisely, time-averaged interaction energies behave typically smoother in terms of the average distance than the corresponding pair-potentials. This averaging effect is referred to as the thermal smoothing effect. Here, we estimate the strength of the thermal smoothing effect on the Lennard-Jones pair-potential for globular proteins at ambient conditions using x-ray diffraction and simulation data of a representative set of proteins. For specific atom species, we find a significant smoothing effect where the time-averaged interaction energy of a single atom pair can differ by various tens of cal/mol from the Lennard-Jones potential at the average distance. Importantly, we observe a dependency of the effect on the local environment of the involved atoms. The effect is typically weaker for bulky backbone atoms in beta sheets than for side-chain atoms belonging to other secondary structure on the surface of the protein. The results of this work have important practical implications for protein software relying on free energy expressions. We show that the accuracy of free energy expressions can largely be increased by introducing environment specific Lennard-Jones parameters accounting for the fact that the typical thermal motion of protein atoms depends strongly on their local environment.

  14. Stochastic resonance induced by novel random transitions of motion of FitzHugh-Nagumo neuron model

    International Nuclear Information System (INIS)

    Zhang Guangjun; Xu Jianxue

    2005-01-01

    In contrast to the previous studies which have dealt with stochastic resonance induced by random transitions of system motion between two coexisting limit cycle attractors in the FitzHugh-Nagumo (FHN) neuron model after Hopf bifurcation and which have dealt with the phenomenon of stochastic resonance induced by external noise when the model with periodic input has only one attractor before Hopf bifurcation, in this paper we have focused our attention on stochastic resonance (SR) induced by a novel transition behavior, the transitions of motion of the model among one attractor on the left side of bifurcation point and two attractors on the right side of bifurcation point under the perturbation of noise. The results of research show: since one bifurcation of transition from one to two limit cycle attractors and the other bifurcation of transition from two to one limit cycle attractors occur in turn besides Hopf bifurcation, the novel transitions of motion of the model occur when bifurcation parameter is perturbed by weak internal noise; the bifurcation point of the model may stochastically slightly shift to the left or right when FHN neuron model is perturbed by external Gaussian distributed white noise, and then the novel transitions of system motion also occur under the perturbation of external noise; the novel transitions could induce SR alone, and when the novel transitions of motion of the model and the traditional transitions between two coexisting limit cycle attractors after bifurcation occur in the same process the SR also may occur with complicated behaviors types; the mechanism of SR induced by external noise when FHN neuron model with periodic input has only one attractor before Hopf bifurcation is related to this kind of novel transition mentioned above

  15. Spring-like motion caused large anisotropic thermal expansion in nonporous M(eim)2 (M = Zn, Cd).

    Science.gov (United States)

    Liu, Zhanning; Liu, Chenxi; Li, Qiang; Chen, Jun; Xing, Xianran

    2017-09-20

    Two nonporous coordination polymers were found to possess large anisotropic thermal expansion, which was derived from the flexible structures. A "spring-like" thermal motion was proposed to illustrate the mechanism. Compound Cd(eim) 2 (eim = 2-ethylimidazole) possesses large linear and reversible thermal expansion properties and the emission intensity shows a linear decrease with temperature, making it a candidate for thermo-responsive materials.

  16. Utilizing Structure-from-Motion Photogrammetry with Airborne Visual and Thermal Images to Monitor Thermal Areas in Yellowstone National Park

    Science.gov (United States)

    Carr, B. B.; Vaughan, R. G.

    2017-12-01

    The thermal areas in Yellowstone National Park (Wyoming, USA) are constantly changing. Persistent monitoring of these areas is necessary to better understand the behavior and potential hazards of both the thermal features and the deeper hydrothermal system driving the observed surface activity. As part of the Park's monitoring program, thousands of visual and thermal infrared (TIR) images have been acquired from a variety of airborne platforms over the past decade. We have used structure-from-motion (SfM) photogrammetry techniques to generate a variety of data products from these images, including orthomosaics, temperature maps, and digital elevation models (DEMs). Temperature maps were generated for Upper Geyser Basin and Norris Geyser Basin for the years 2009-2015, by applying SfM to nighttime TIR images collected from an aircraft-mounted forward-looking infrared (FLIR) camera. Temperature data were preserved through the SfM processing by applying a uniform linear stretch over the entire image set to convert between temperature and a 16-bit digital number. Mosaicked temperature maps were compared to the original FLIR image frames and to ground-based temperature data to constrain the accuracy of the method. Due to pixel averaging and resampling, among other issues, the derived temperature values are typically within 5-10 ° of the values of the un-resampled image frame. We also created sub-meter resolution DEMs from airborne daytime visual images of individual thermal areas. These DEMs can be used for resource and hazard management, and in cases where multiple DEMs exist from different times, for measuring topographic change, including change due to thermal activity. For example, we examined the sensitivity of the DEMs to topographic change by comparing DEMs of the travertine terraces at Mammoth Hot Springs, which can grow at > 1 m per year. These methods are generally applicable to images from airborne platforms, including planes, helicopters, and unmanned aerial

  17. Stochastic analysis of uncertain thermal parameters for random thermal regime of frozen soil around a single freezing pipe

    Science.gov (United States)

    Wang, Tao; Zhou, Guoqing; Wang, Jianzhou; Zhou, Lei

    2018-03-01

    The artificial ground freezing method (AGF) is widely used in civil and mining engineering, and the thermal regime of frozen soil around the freezing pipe affects the safety of design and construction. The thermal parameters can be truly random due to heterogeneity of the soil properties, which lead to the randomness of thermal regime of frozen soil around the freezing pipe. The purpose of this paper is to study the one-dimensional (1D) random thermal regime problem on the basis of a stochastic analysis model and the Monte Carlo (MC) method. Considering the uncertain thermal parameters of frozen soil as random variables, stochastic processes and random fields, the corresponding stochastic thermal regime of frozen soil around a single freezing pipe are obtained and analyzed. Taking the variability of each stochastic parameter into account individually, the influences of each stochastic thermal parameter on stochastic thermal regime are investigated. The results show that the mean temperatures of frozen soil around the single freezing pipe with three analogy method are the same while the standard deviations are different. The distributions of standard deviation have a great difference at different radial coordinate location and the larger standard deviations are mainly at the phase change area. The computed data with random variable method and stochastic process method have a great difference from the measured data while the computed data with random field method well agree with the measured data. Each uncertain thermal parameter has a different effect on the standard deviation of frozen soil temperature around the single freezing pipe. These results can provide a theoretical basis for the design and construction of AGF.

  18. Intermittent thermal plasma acceleration linked to sporadic motions of the magnetopause, first Cluster results

    Directory of Open Access Journals (Sweden)

    J.-A. Sauvaud

    Full Text Available This paper presents the first observations with Cluster of a very dense population of thermal ionospheric ions (H+, He+, O+ locally "accelerated" perpendicularly to the local magnetic field in a region adjacent to the magnetopause and on its magnetospheric side. The observation periods follow a long period of very weak magnetic activity. Recurrent motions of the magnetopause are, in the presented cases, unexpectedly associated with the appearance inside closed field lines of recurrent energy structures of ionospheric ions with energies in the 5 eV to  ~1000 eV range. The heaviest ions were detected with the highest energies. Here, the ion behaviour is interpreted as resulting from local electric field enhancements/decreases which adiabatically enhance/lower the bulk energy of a local dense thermal ion population. This drift effect, which is directly linked to magnetopause motions caused by pressure changes, allows for the thermal ions to overcome the satellite potential and be detected by the suprathermal CIS Cluster experiment. When fast flowing, i.e. when detectable, the density (~ 1 cm-3 of these ions from a terrestrial origin is (in the cases presented here largely higher than the local density of ions from magnetospheric/plasma sheet origin which poses again the question of the relative importance of solar and ionospheric sources for the magnetospheric plasma even during very quiet magnetic conditions.

    Key words. Ionosphere (planetary ionosphere; plasma convection Magnetospheric physics (magnetopause, cusp and boundary layers

  19. Weak Ergodicity Breaking of Receptor Motion in Living Cells Stemming from Random Diffusivity

    Science.gov (United States)

    Manzo, Carlo; Torreno-Pina, Juan A.; Massignan, Pietro; Lapeyre, Gerald J.; Lewenstein, Maciej; Garcia Parajo, Maria F.

    2015-01-01

    Molecular transport in living systems regulates numerous processes underlying biological function. Although many cellular components exhibit anomalous diffusion, only recently has the subdiffusive motion been associated with nonergodic behavior. These findings have stimulated new questions for their implications in statistical mechanics and cell biology. Is nonergodicity a common strategy shared by living systems? Which physical mechanisms generate it? What are its implications for biological function? Here, we use single-particle tracking to demonstrate that the motion of dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin (DC-SIGN), a receptor with unique pathogen-recognition capabilities, reveals nonergodic subdiffusion on living-cell membranes In contrast to previous studies, this behavior is incompatible with transient immobilization, and, therefore, it cannot be interpreted according to continuous-time random-walk theory. We show that the receptor undergoes changes of diffusivity, consistent with the current view of the cell membrane as a highly dynamic and diverse environment. Simulations based on a model of an ordinary random walk in complex media quantitatively reproduce all our observations, pointing toward diffusion heterogeneity as the cause of DC-SIGN behavior. By studying different receptor mutants, we further correlate receptor motion to its molecular structure, thus establishing a strong link between nonergodicity and biological function. These results underscore the role of disorder in cell membranes and its connection with function regulation. Because of its generality, our approach offers a framework to interpret anomalous transport in other complex media where dynamic heterogeneity might play a major role, such as those found, e.g., in soft condensed matter, geology, and ecology.

  20. Bounds on the vibrational energy that can be harvested from random base motion

    Science.gov (United States)

    Langley, R. S.

    2015-03-01

    This paper is concerned with the development of upper bounds on the energy harvesting performance of a general multi-degree-of-freedom nonlinear electromechanical system that is subjected to random base motion and secondary applied periodic forces. The secondary forces are applied with the aim of enhancing the energy harvested from the base motion, and they may constitute direct excitation, or they may produce parametric terms in the equations of motion. It is shown that when the base motion has white noise acceleration then the power input by the base is always πS0 M / 2 where S0 is the single sided spectral density of the acceleration, and M is the mass of the system. This implies that although the secondary forces may enhance the energy harvested by causing a larger fraction of the power input from the base to be harvested rather than dissipated, there is an upper limit on the power that can be harvested. Attention is then turned to narrow band excitation, and it is found that in the absence of secondary forces a bound can be derived for a single degree of freedom system with linear damping and arbitrary nonlinear stiffness. The upper bound on the power input by the base is πM max [ S (ω) ] / 2, where S (ω) is the single sided base acceleration spectrum. The validity of this result for more general systems is found to be related to the properties of the first Wiener kernel, and this issue is explored analytically and by numerical simulation.

  1. A Randomized Controlled Trial of Lorazepam to Reduce Liver Motion in Patients Receiving Upper Abdominal Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Tsang, Derek S.; Voncken, Francine E.M.; Tse, Regina V. [Princess Margaret Cancer Centre, University Health Network, Department of Radiation Oncology, University of Toronto, Toronto (Canada); Sykes, Jenna [Department of Biostatistics, Princess Margaret Cancer Centre, University Health Network, Toronto (Canada); Wong, Rebecca K.S.; Dinniwell, Rob E.; Kim, John; Ringash, Jolie; Brierley, James D.; Cummings, Bernard J.; Brade, Anthony [Princess Margaret Cancer Centre, University Health Network, Department of Radiation Oncology, University of Toronto, Toronto (Canada); Dawson, Laura A., E-mail: laura.dawson@rmp.uhn.on.ca [Princess Margaret Cancer Centre, University Health Network, Department of Radiation Oncology, University of Toronto, Toronto (Canada)

    2013-12-01

    Purpose: Reduction of respiratory motion is desirable to reduce the volume of normal tissues irradiated, to improve concordance of planned and delivered doses, and to improve image guided radiation therapy (IGRT). We hypothesized that pretreatment lorazepam would lead to a measurable reduction of liver motion. Methods and Materials: Thirty-three patients receiving upper abdominal IGRT were recruited to a double-blinded randomized controlled crossover trial. Patients were randomized to 1 of 2 study arms: arm 1 received lorazepam 2 mg by mouth on day 1, followed by placebo 4 to 8 days later; arm 2 received placebo on day 1, followed by lorazepam 4 to 8 days later. After tablet ingestion and daily radiation therapy, amplitude of liver motion was measured on both study days. The primary outcomes were reduction in craniocaudal (CC) liver motion using 4-dimensional kV cone beam computed tomography (CBCT) and the proportion of patients with liver motion ≤5 mm. Secondary endpoints included motion measured with cine magnetic resonance imaging and kV fluoroscopy. Results: Mean relative and absolute reduction in CC amplitude with lorazepam was 21% and 2.5 mm respectively (95% confidence interval [CI] 1.1-3.9, P=.001), as assessed with CBCT. Reduction in CC amplitude to ≤5 mm residual liver motion was seen in 13% (95% CI 1%-25%) of patients receiving lorazepam (vs 10% receiving placebo, P=NS); 65% (95% CI 48%-81%) had reduction in residual CC liver motion to ≤10 mm (vs 52% with placebo, P=NS). Patients with large respiratory movement and patients who took lorazepam ≥60 minutes before imaging had greater reductions in liver CC motion. Mean reductions in liver CC amplitude on magnetic resonance imaging and fluoroscopy were nonsignificant. Conclusions: Lorazepam reduces liver motion in the CC direction; however, average magnitude of reduction is small, and most patients have residual motion >5 mm.

  2. Thermally Induced Lateral Motion of α-Zirconium Phosphate Layers Intercalated with Hexadecylamines

    Science.gov (United States)

    Char, Kookheon

    2005-03-01

    Well-defined intercalated structure, either interdigitated layers or bilayers, of hexadecylamines (HDAs) in a confined space of a highly-functionalized layered material, α- zirconium phosphate (α-ZrP), was prepared and these two distinct intercalated structures can serve as model systems to investigate the interaction of the two monolayers whose amphiphilic tails are adjacent to each other. Acidic functional groups (-POH) on the α-ZrP are in well-ordered array and the number of functional group is quite high (i.e., cationic exchange capacity (CEC) = 664 mmole/100 g, area per one charge site = 0.24 nm^2) enough to realize the bilayers (i.e., discrete two monolayers) of HDAs within the α-ZrP interlayer. We employed the two-step intercalation mechanism for the preparation of well- ordered interdigitated layers as well as the bilayers of alkyl chains attached to both sides of the α-ZrP intergallery. An intriguing lateral motion of the α-ZrP sheets was observed with in-situ SAXS measurements for the interdigitated layer during heating and cooling cycle and verified with TEM. This lateral motion is believed to be due to the transition from the tilted to the untilted conformation of the interdigitated HDA chains and this transition is found to be thermally reversible.

  3. Degree distributions of the visibility graphs mapped from fractional Brownian motions and multifractal random walks

    International Nuclear Information System (INIS)

    Ni Xiaohui; Jiang Zhiqiang; Zhou Weixing

    2009-01-01

    The dynamics of a complex system is usually recorded in the form of time series, which can be studied through its visibility graph from a complex network perspective. We investigate the visibility graphs extracted from fractional Brownian motions and multifractal random walks, and find that the degree distributions exhibit power-law behaviors, in which the power-law exponent α is a linear function of the Hurst index H of the time series. We also find that the degree distribution of the visibility graph is mainly determined by the temporal correlation of the original time series with minor influence from the possible multifractal nature. As an example, we study the visibility graphs constructed from three Chinese stock market indexes and unveil that the degree distributions have power-law tails, where the tail exponents of the visibility graphs and the Hurst indexes of the indexes are close to the α∼H linear relationship.

  4. Random blebbing motion: A simple model linking cell structural properties to migration characteristics

    Science.gov (United States)

    Woolley, Thomas E.; Gaffney, Eamonn A.; Goriely, Alain

    2017-07-01

    If the plasma membrane of a cell is able to delaminate locally from its actin cortex, a cellular bleb can be produced. Blebs are pressure-driven protrusions, which are noteworthy for their ability to produce cellular motion. Starting from a general continuum mechanics description, we restrict ourselves to considering cell and bleb shapes that maintain approximately spherical forms. From this assumption, we obtain a tractable algebraic system for bleb formation. By including cell-substrate adhesions, we can model blebbing cell motility. Further, by considering mechanically isolated blebbing events, which are randomly distributed over the cell, we can derive equations linking the macroscopic migration characteristics to the microscopic structural parameters of the cell. This multiscale modeling framework is then used to provide parameter estimates, which are in agreement with current experimental data. In summary, the construction of the mathematical model provides testable relationships between the bleb size and cell motility.

  5. Random blebbing motion: A simple model linking cell structural properties to migration characteristics.

    Science.gov (United States)

    Woolley, Thomas E; Gaffney, Eamonn A; Goriely, Alain

    2017-07-01

    If the plasma membrane of a cell is able to delaminate locally from its actin cortex, a cellular bleb can be produced. Blebs are pressure-driven protrusions, which are noteworthy for their ability to produce cellular motion. Starting from a general continuum mechanics description, we restrict ourselves to considering cell and bleb shapes that maintain approximately spherical forms. From this assumption, we obtain a tractable algebraic system for bleb formation. By including cell-substrate adhesions, we can model blebbing cell motility. Further, by considering mechanically isolated blebbing events, which are randomly distributed over the cell, we can derive equations linking the macroscopic migration characteristics to the microscopic structural parameters of the cell. This multiscale modeling framework is then used to provide parameter estimates, which are in agreement with current experimental data. In summary, the construction of the mathematical model provides testable relationships between the bleb size and cell motility.

  6. Random walks in nanotube composites: Improved algorithms and the role of thermal boundary resistance

    International Nuclear Information System (INIS)

    Duong, Hai M.; Papavassiliou, Dimitrios V.; Lee, Lloyd L.; Mullen, Kieran J.

    2005-01-01

    Random walk simulations of thermal walkers are used to study the effect of interfacial resistance on heat flow in randomly dispersed carbon nanotube composites. The adopted algorithm effectively makes the thermal conductivity of the nanotubes themselves infinite. The probability that a walker colliding with a matrix-nanotube interface reflects back into the matrix phase or crosses into the carbon nanotube phase is determined by the thermal boundary (Kapitza) resistance. The use of 'cold' and 'hot' walkers produces a steady state temperature profile that allows accurate determination of the thermal conductivity. The effects of the carbon nanotube orientation, aspect ratio, volume fraction, and Kapitza resistance on the composite effective conductivity are quantified

  7. Enhancing Motion-In-Depth Perception of Random-Dot Stereograms.

    Science.gov (United States)

    Zhang, Di; Nourrit, Vincent; De Bougrenet de la Tocnaye, Jean-Louis

    2018-07-01

    Random-dot stereograms have been widely used to explore the neural mechanisms underlying binocular vision. Although they are a powerful tool to stimulate motion-in-depth (MID) perception, published results report some difficulties in the capacity to perceive MID generated by random-dot stereograms. The purpose of this study was to investigate whether the performance of MID perception could be improved using an appropriate stimulus design. Sixteen inexperienced observers participated in the experiment. A training session was carried out to improve the accuracy of MID detection before the experiment. Four aspects of stimulus design were investigated: presence of a static reference, background texture, relative disparity, and stimulus contrast. Participants' performance in MID direction discrimination was recorded and compared to evaluate whether varying these factors helped MID perception. Results showed that only the presence of background texture had a significant effect on MID direction perception. This study provides suggestions for the design of 3D stimuli in order to facilitate MID perception.

  8. A novel approach to generate random surface thermal loads in piping

    Energy Technology Data Exchange (ETDEWEB)

    Costa Garrido, Oriol, E-mail: oriol.costa@ijs.si; El Shawish, Samir; Cizelj, Leon

    2014-07-01

    Highlights: • Approach for generating continuous and time-dependent random thermal fields. • Temperature fields simulate fluid mixing thermal loads at fluid–wall interface. • Through plane-wave decomposition, experimental temperature statistics are reproduced. • Validation of the approach with a case study from literature. • Random surface thermal loads generation for future thermal fatigue analyses of piping. - Abstract: There is a need to perform three-dimensional mechanical analyses of pipes, subjected to complex thermo-mechanical loadings such as the ones evolving from turbulent fluid mixing in a T-junction. A novel approach is proposed in this paper for fast and reliable generation of random thermal loads at the pipe surface. The resultant continuous and time-dependent temperature fields simulate the fluid mixing thermal loads at the fluid–wall interface. The approach is based on reproducing discrete fluid temperature statistics, from experimental readings or computational fluid dynamic simulation's results, at interface locations through plane-wave decomposition of temperature fluctuations. The obtained random thermal fields contain large scale instabilities such as cold and hot spots traveling at flow velocities. These low frequency instabilities are believed to be among the major causes of the thermal fatigue in T-junction configurations. The case study found in the literature has been used to demonstrate the generation of random surface thermal loads. The thermal fields generated with the proposed approach are statistically equivalent (within the first two moments) to those from CFD simulations results of similar characteristics. The fields maintain the input data at field locations for a large set of parameters used to generate the thermal loads. This feature will be of great advantage in future sensitivity fatigue analyses of three-dimensional pipe structures.

  9. A novel approach to generate random surface thermal loads in piping

    International Nuclear Information System (INIS)

    Costa Garrido, Oriol; El Shawish, Samir; Cizelj, Leon

    2014-01-01

    Highlights: • Approach for generating continuous and time-dependent random thermal fields. • Temperature fields simulate fluid mixing thermal loads at fluid–wall interface. • Through plane-wave decomposition, experimental temperature statistics are reproduced. • Validation of the approach with a case study from literature. • Random surface thermal loads generation for future thermal fatigue analyses of piping. - Abstract: There is a need to perform three-dimensional mechanical analyses of pipes, subjected to complex thermo-mechanical loadings such as the ones evolving from turbulent fluid mixing in a T-junction. A novel approach is proposed in this paper for fast and reliable generation of random thermal loads at the pipe surface. The resultant continuous and time-dependent temperature fields simulate the fluid mixing thermal loads at the fluid–wall interface. The approach is based on reproducing discrete fluid temperature statistics, from experimental readings or computational fluid dynamic simulation's results, at interface locations through plane-wave decomposition of temperature fluctuations. The obtained random thermal fields contain large scale instabilities such as cold and hot spots traveling at flow velocities. These low frequency instabilities are believed to be among the major causes of the thermal fatigue in T-junction configurations. The case study found in the literature has been used to demonstrate the generation of random surface thermal loads. The thermal fields generated with the proposed approach are statistically equivalent (within the first two moments) to those from CFD simulations results of similar characteristics. The fields maintain the input data at field locations for a large set of parameters used to generate the thermal loads. This feature will be of great advantage in future sensitivity fatigue analyses of three-dimensional pipe structures

  10. Thermal motion of carbon clusters and production of carbon nanotubes by gravity-free arc discharge

    International Nuclear Information System (INIS)

    Mieno, T.; Takeguchi, M.

    2006-01-01

    Thermal and diffusion properties of hot gas around a dc arc discharge under a gravity-free condition are investigated using a jet plane in order to improve the arc production of carbon clusters. Spherically symmetric temperature distribution of He gas around the arc plasma and monotonic slow expansion of the high-temperature region are observed. By means of the passive-type Mie scattering method, random slow diffusion of carbon clusters around the arc plasma is clearly observed under the gravity-free condition. This indicates that carbon clusters including single-walled carbon nanotubes are synthesized around the arc plasma where the He temperature is higher than 1000 K. It is confirmed that large bundles of fatter single-walled carbon nanotubes are produced under the gravity-free condition

  11. Fluids in micropores. V. Effects of thermal motion in the walls of a slit-micropore

    International Nuclear Information System (INIS)

    Diestler, D.J.; Schoen, M.

    1996-01-01

    Previous articles in this series have concerned the prototypal slit-pore with rigid walls, in which a Lennard-Jones (12,6) monatomic film is constrained between two plane-parallel walls comprising like atoms fixed in the face-centered-cubic (fcc) (100) configuration. The behavior of molecularly thin films in the rigid-wall prototype is governed by the template effect, whereby solid films can form epitaxially when the walls are properly aligned in the lateral directions. In this article the influence of thermal motion of the wall atoms on the template effect is investigated. The walls are treated as Einstein solids, the atoms moving independently in harmonic potentials centered on rigidly fixed equilibrium positions in the fcc (100) configuration. The force constant f c is a measure of the stiffness of the walls, the rigid-wall limit being f c =∞. Formal thermodynamic and statistical mechanical analyses of the system are carried out. The results of grand canonical ensemble Monte Carlo simulations indicate that for values of f c characteristic of a soft (e.g., noble-gas) crystal dynamic coupling between wall and film has a substantial influence on such equilibrium properties as normal stress (load) and interfacial tensions. In general, the softer the walls (i.e., the smaller the value of f c ), the weaker the template effect and hence the softer and more disordered the confined film. copyright 1996 American Institute of Physics

  12. Survey of strong motion earthquake effects on thermal power plants in California with emphasis on piping systems. Volume 2, Appendices

    International Nuclear Information System (INIS)

    Stevenson, J.D.

    1995-11-01

    Volume 2 of the ''Survey of Strong Motion Earthquake Effects on Thermal Power Plants in California with Emphasis on Piping Systems'' contains Appendices which detail the detail design and seismic response of several power plants subjected to strong motion earthquakes. The particular plants considered include the Ormond Beach, Long Beach and Seal Beach, Burbank, El Centro, Glendale, Humboldt Bay, Kem Valley, Pasadena and Valley power plants. Included is a typical power plant piping specification and photographs of typical power plant piping specification and photographs of typical piping and support installations for the plants surveyed. Detailed piping support spacing data are also included

  13. Heave motion prediction of a large barge in random seas by using artificial neural network

    Science.gov (United States)

    Lee, Hsiu Eik; Liew, Mohd Shahir; Zawawi, Noor Amila Wan Abdullah; Toloue, Iraj

    2017-11-01

    This paper describes the development of a multi-layer feed forward artificial neural network (ANN) to predict rigid heave body motions of a large catenary moored barge subjected to multi-directional irregular waves. The barge is idealized as a rigid plate of finite draft with planar dimensions 160m (length) and 100m (width) which is held on station using a six point chain catenary mooring in 50m water depth. Hydroelastic effects are neglected from the physical model as the chief intent of this study is focused on large plate rigid body hydrodynamics modelling using ANN. Even with this assumption, the computational requirements for time domain coupled hydrodynamic simulations of a moored floating body is considerably costly, particularly if a large number of simulations are required such as in the case of response based design (RBD) methods. As an alternative to time consuming numerical hydrodynamics, a regression-type ANN model has been developed for efficient prediction of the barge's heave responses to random waves from various directions. It was determined that a network comprising of 3 input features, 2 hidden layers with 5 neurons each and 1 output was sufficient to produce acceptable predictions within 0.02 mean squared error. By benchmarking results from the ANN with those generated by a fully coupled dynamic model in OrcaFlex, it is demonstrated that the ANN is capable of predicting the barge's heave responses with acceptable accuracy.

  14. LCoMotion - Learning, Cognition and Motion; a multicomponent cluster randomized school-based intervention aimed at increasing learning and cognition - rationale, design and methods.

    Science.gov (United States)

    Bugge, Anna; Tarp, Jakob; Østergaard, Lars; Domazet, Sidsel Louise; Andersen, Lars Bo; Froberg, Karsten

    2014-09-18

    The aim of the study; LCoMotion - Learning, Cognition and Motion was to develop, document, and evaluate a multi-component physical activity (PA) intervention in public schools in Denmark. The primary outcome was cognitive function. Secondary outcomes were academic skills, body composition, aerobic fitness and PA. The primary aim of the present paper was to describe the rationale, design and methods of the LCoMotion study. LCoMotion was designed as a cluster-randomized controlled study. Fourteen schools from all five regions in Denmark participated. All students from 6th and 7th grades were invited to participate (n = 869) and consent was obtained for 87% (n = 759). Baseline measurements were obtained in November/December 2013 and follow-up measurements in May/June 2014. The intervention lasted five months and consisted of a "package" of three main components: PA during academic lessons, PA during recess and PA homework. Furthermore a cycling campaign was conducted during the intervention period. Intervention schools should endeavor to ensure that students were physically active for at least 60 min every school day. Cognitive function was measured by a modified Eriksen flanker task and academic skills by a custom made mathematics test. PA was objectively measured by accelerometers (ActiGraph, GT3X and GT3X+) and aerobic fitness assessed by an intermittent shuttle-run test (the Andersen intermittent running test). Furthermore, compliance with the intervention was assessed by short message service (SMS)-tracking and questionnaires were delivered to students, parents and teachers. LCoMotion has ability to provide new insights on the effectiveness of a multicomponent intervention on cognitive function and academic skills in 6th and 7th grade students. Clinicaltrials.gov: NCT02012881 (10/10/2013).

  15. The effects of thermal motion of neutrals on the non-potential instabilities in a weakly sodium plasma

    International Nuclear Information System (INIS)

    Zigman, V.J.; Milic, B.S.

    1982-01-01

    The results of recent experimental measurements of the differential cross-section for elastic scattering of electrons on sodium atoms are used to evaluate the electron steady-state distribution function in a weakly ionized, uniform and non-magnetized sodium plasma placed in a d.c. electric field. The field is assumed to be of moderate intensity, so that the thermal motion of the neutrals has to be taken into account in the evaluation of the distribution function. The resulting 'modified Druyvesteinian function' is applied to study the non-potential instabilities arising from the presence of the field in this particular plasma. Threshold drifts for both very slow and slow modes are obtained and the conditions for the onset of instabilities are discussed. It is shown that the thermal motion of the neutrals affects both critical drifts and the angles of propagation. (author)

  16. Auricular Acupressure for Managing Postoperative Pain and Knee Motion in Patients with Total Knee Replacement: A Randomized Sham Control Study

    Directory of Open Access Journals (Sweden)

    Ling-hua Chang

    2012-01-01

    Full Text Available Background. Postoperative pain management remains a significant challenge for all healthcare providers. A randomized controlled trial was conducted to examine the adjuvant effects of auricular acupressure on relieving postoperative pain and improving the passive range of motion in patients with total knee replacement (TKR. Method. Sixty-two patients who had undergone a TKR were randomly assigned to the acupressure group and the sham control group. The intervention was delivered three times a day for 3 days. A visual analog scale (VAS and the Short-Form McGill Pain Questionnaire were used to assess pain intensity. Pain medication consumption was recorded, and the knee motion was measured using a goniometer. Results. The patients experienced a moderately severe level of pain postoperatively (VAS 58.66 ± 20.35 while being on the routine PCA. No differences were found in pain scores between the groups at all points. However, analgesic drug usage in the acupressure group patients was significantly lower than in the sham control group (<0.05, controlling for BMI, age, and pain score. On the 3rd day after surgery, the passive knee motion in the acupressure group patients was significantly better than in the sham control group patients (<0.05, controlling for BMI. Conclusion. The application of auricular acupressure at specific therapeutic points significantly reduces the opioid analgesia requirement and improves the knee motion in patients with TKR.

  17. Fabrication of Random Microwell Arrays as Pseudo-Thermal Speckle Light Source

    Directory of Open Access Journals (Sweden)

    Axiu Cao

    2018-05-01

    Full Text Available Quantum correlated imaging using the intensity fluctuations of thermal light possesses advantages of high resolution and strong anti-interference ability. The common method to produce pseudo-thermal light source is using a rotary ground glass and transmission of laser beam. In the present work, we propose a method for the fabrication of microwell arrays with randomly varied diameters, which could be used as a new structural element for pseudo-thermal speckle light source. If these are etched with random sizes then they may also have random and complex varying curvatures (diffusion limited etching leading to random destructive interference of the coherent beam which could be a good thing. The microwell arrays, with diameters randomly varying from 5 μm to 40 μm, height varying from 200 nm to 20 μm, were fabricated by photolithography combined with acid etching. The experimental conditions are simple and can be scaled up to for large structures. The produced microwell arrays can transform the laser beam to a pseudo-thermal light source with a certain divergent angle by rational designing of mask and adjustable process parameters.

  18. Randomness control of vehicular motion through a sequence of traffic signals at irregular intervals

    International Nuclear Information System (INIS)

    Nagatani, Takashi

    2010-01-01

    We study the regularization of irregular motion of a vehicle moving through the sequence of traffic signals with a disordered configuration. Each traffic signal is controlled by both cycle time and phase shift. The cycle time is the same for all signals, while the phase shift varies from signal to signal by synchronizing with intervals between a signal and the next signal. The nonlinear dynamic model of the vehicular motion is presented by the stochastic nonlinear map. The vehicle exhibits the very complex behavior with varying both cycle time and strength of irregular intervals. The irregular motion induced by the disordered configuration is regularized by adjusting the phase shift within the regularization regions.

  19. Deleterious Thermal Effects due to Randomized Flow Paths in Pebble Bed, and Particle Bed Style Reactors

    Science.gov (United States)

    Moran, Robert P.

    2013-01-01

    Reactor fuel rod surface area that is perpendicular to coolant flow direction (+S) i.e. perpendicular to the P creates areas of coolant stagnation leading to increased coolant temperatures resulting in localized changes in fluid properties. Changes in coolant fluid properties caused by minor increases in temperature lead to localized reductions in coolant mass flow rates leading to localized thermal instabilities. Reductions in coolant mass flow rates result in further increases in local temperatures exacerbating changes to coolant fluid properties leading to localized thermal runaway. Unchecked localized thermal runaway leads to localized fuel melting. Reactor designs with randomized flow paths are vulnerable to localized thermal instabilities, localized thermal runaway, and localized fuel melting.

  20. On correlations between certain random variables associated with first passage Brownian motion

    International Nuclear Information System (INIS)

    Kearney, Michael J; Pye, Andrew J; Martin, Richard J

    2014-01-01

    We analyse how the area swept out by a Brownian motion up to its first passage time correlates with the first passage time itself, obtaining several exact results in the process. Additionally, we analyse the relationship between the time average of a Brownian motion during a first passage and the maximum value attained. The results, which find various applications, are in excellent agreement with simulations. (paper)

  1. Correlated thermal motion of two liquid Pb inclusions attached to a fixed dislocation in an Al matrix

    DEFF Research Database (Denmark)

    Prokofjev, Sergei I.; Johnson, Erik

    2017-01-01

    of the inclusions on the dislocation line occurs as a result of their mutual repulsion and their repulsion from the fixed ends of the dislocation caused by the dislocation line tension. The oscillations of the inclusions can be considered as correlated thermal motion in coupled potential wells. The effective...... potentials, in which the inclusions move, and the effective potential of their interactions are evaluated. It is found that the spatial correlations of the positions of the inclusions on the dislocation depend strongly on the interaction potential. The observed correlations of the positions of the inclusions...

  2. High-K precession modes: Axially symmetric limit of wobbling motion in the cranked random-phase approximation description

    International Nuclear Information System (INIS)

    Shimizu, Yoshifumi R.; Matsuzaki, Masayuki; Matsuyanagi, Kenichi

    2005-01-01

    The rotational band built on the high-K multi-quasiparticle state can be interpreted as a multi-phonon band of the precession mode, which represents the precessional rotation about the axis perpendicular to the direction of the intrinsic angular momentum. By using the axially symmetric limit of the random-phase approximation (RPA) formalism developed for the nuclear wobbling motion, we study the properties of the precession modes in 178 W: the excitation energies, B(E2) and B(M1) values. We show that the excitations of such a specific type of rotation can be well described by the RPA formalism, which gives new insight into the wobbling motion in the triaxial superdeformed nuclei from a microscopic viewpoint

  3. Molecular Dynamics Study of Thermally Augmented Nanodroplet Motion on Chemical Energy Induced Wettability Gradient Surfaces.

    Science.gov (United States)

    Chakraborty, Monojit; Chowdhury, Anamika; Bhusan, Richa; DasGupta, Sunando

    2015-10-20

    Droplet motion on a surface with chemical energy induced wettability gradient has been simulated using molecular dynamics (MD) simulation to highlight the underlying physics of molecular movement near the solid-liquid interface including the contact line friction. The simulations mimic experiments in a comprehensive manner wherein microsized droplets are propelled by the surface wettability gradient against forces opposed to motion. The liquid-wall Lennard-Jones interaction parameter and the substrate temperature are varied to explore their effects on the three-phase contact line friction coefficient. The contact line friction is observed to be a strong function of temperature at atomistic scales, confirming their experimentally observed inverse functionality. Additionally, the MD simulation results are successfully compared with those from an analytical model for self-propelled droplet motion on gradient surfaces.

  4. Quantum and thermal ionic motion, oxygen isotope effect, and superexchange distribution in La2CuO4

    DEFF Research Database (Denmark)

    Haefliger, P. S.; Gerber, S.; Pramod, R.

    2014-01-01

    We study the zero-point and thermal ionic motion in La2CuO4 by means of high-resolution neutron-diffraction experiments. Our results demonstrate anisotropic motion of O and, to a lesser extent, Cu ions, both consistent with the structure of coupled CuO6 octahedra, and quantify the relative effect...... in J values that are subject to significant (8-12%) isotope effects. We demonstrate that this motional broadening of J can have substantial effects on certain electronic and magnetic properties in cuprates.......We study the zero-point and thermal ionic motion in La2CuO4 by means of high-resolution neutron-diffraction experiments. Our results demonstrate anisotropic motion of O and, to a lesser extent, Cu ions, both consistent with the structure of coupled CuO6 octahedra, and quantify the relative effects...

  5. Trunk motion visual feedback during walking improves dynamic balance in older adults: Assessor blinded randomized controlled trial.

    Science.gov (United States)

    Anson, Eric; Ma, Lei; Meetam, Tippawan; Thompson, Elizabeth; Rathore, Roshita; Dean, Victoria; Jeka, John

    2018-05-01

    Virtual reality and augmented feedback have become more prevalent as training methods to improve balance. Few reports exist on the benefits of providing trunk motion visual feedback (VFB) during treadmill walking, and most of those reports only describe within session changes. To determine whether trunk motion VFB treadmill walking would improve over-ground balance for older adults with self-reported balance problems. 40 adults (75.8 years (SD 6.5)) with self-reported balance difficulties or a history of falling were randomized to a control or experimental group. Everyone walked on a treadmill at a comfortable speed 3×/week for 4 weeks in 2 min bouts separated by a seated rest. The control group was instructed to look at a stationary bulls-eye target while the experimental group also saw a moving cursor superimposed on the stationary bulls-eye that represented VFB of their walking trunk motion. The experimental group was instructed to keep the cursor in the center of the bulls-eye. Somatosensory (monofilaments and joint position testing) and vestibular function (canal specific clinical head impulses) was evaluated prior to intervention. Balance and mobility were tested before and after the intervention using Berg Balance Test, BESTest, mini-BESTest, and Six Minute Walk. There were no significant differences between groups before the intervention. The experimental group significantly improved on the BESTest (p = 0.031) and the mini-BEST (p = 0.019). The control group did not improve significantly on any measure. Individuals with more profound sensory impairments had a larger improvement on dynamic balance subtests of the BESTest. Older adults with self-reported balance problems improve their dynamic balance after training using trunk motion VFB treadmill walking. Individuals with worse sensory function may benefit more from trunk motion VFB during walking than individuals with intact sensory function. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Effect of Continuous Motion Parameter Feedback on Laparoscopic Simulation Training: A Prospective Randomized Controlled Trial on Skill Acquisition and Retention.

    Science.gov (United States)

    Buescher, Julian Frederik; Mehdorn, Anne-Sophie; Neumann, Philipp-Alexander; Becker, Felix; Eichelmann, Ann-Kathrin; Pankratius, Ulrich; Bahde, Ralf; Foell, Daniel; Senninger, Norbert; Rijcken, Emile

    To investigate the effect of motion parameter feedback on laparoscopic basic skill acquisition and retention during a standardized box training curriculum. A Lap-X Hybrid laparoscopic simulator was designed to provide individual and continuous motion parameter feedback in a dry box trainer setting. In a prospective controlled trial, surgical novices were randomized into 2 groups (regular box group, n = 18, and Hybrid group, n = 18) to undergo an identical 5-day training program. In each group, 7 standardized tasks on laparoscopic basic skills were completed twice a day on 4 consecutive days in fixed pairs. Additionally, each participant performed a simulated standard laparoscopic cholecystectomy before (day 1) and after training (day 5) on a LAP Mentor II virtual reality (VR) trainer, allowing an independent control of skill progress in both groups. A follow-up assessment of skill retention was performed after 6 weeks with repetition of both the box tasks and VR cholecystectomy. Muenster University Hospital Training Center, Muenster, Germany. Medical students without previous surgical experience. Laparoscopic skills in both groups improved significantly during the training period, measured by the overall task performance time. The 6 week follow-up showed comparable skill retention in both groups. Evaluation of the VR cholecystectomies demonstrated significant decrease of operation time (p Simulation training on both trainers enables reliable acquisition of laparoscopic basic skills. Furthermore, individual and continuous motion feedback improves laparoscopic skill enhancement significantly in several aspects. Thus, training systems with feedback of motion parameters should be considered to achieve long-term improvement of motion economy among surgical trainees. Copyright © 2017 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  7. Thermal welding versus cold knife tonsillectomy: A prospective randomized study

    Directory of Open Access Journals (Sweden)

    Metin Yilmaz

    2012-05-01

    Full Text Available This is a prospective randomized study conducted in a group of children who underwent two methods of tonsillectomy: thermal welding or cold knife tonsillectomy. Parameters, such as postoperative pain scores, intraoperative blood loss, operation time, and postoperative bleeding rates, were analyzed to find out which technique is better. Ninety-one children (aged between 2 years and 13 years with recurrent tonsillitis, obstructive sleep apnea syndrome, or both were included in the study. According to the type of tonsillectomy procedure, the patients were divided into two groups: cold knife and thermal welding procedure. The two groups were compared on the basis of postoperative pain scores, intraoperative blood loss, operation time, and postoperative bleeding. Fifty-seven patients underwent thermal welding tonsillectomy and 34 had cold knife tonsillectomy. The mean pain score in thermal welding group was significantly lower (p<0.001. There was no remarkable blood loss intraoperatively in the thermal welding procedure. The operation time was not significantly different between two groups. No postoperative bleeding was encountered in the thermal welding group. Compared with the cold knife technique, thermal welding was found to be a relatively new and safe technique for tonsillectomy as it results in significantly less postoperative pain and no remarkable blood loss.

  8. Molecular dynamics simulations for the motion of evaporative droplets driven by thermal gradients along nanochannels

    KAUST Repository

    Wu, Congmin; Xu, Xinpeng; Qian, Tiezheng

    2013-01-01

    -vapor coexistence temperature in one-component fluids while the solid surface is almost isothermal for solids of high thermal conductivity. Therefore, a temperature discontinuity is formed if the two isothermal interfaces are of different temperatures and intersect

  9. Motional properties of unfolded ubiquitin: a model for a random coil protein

    Energy Technology Data Exchange (ETDEWEB)

    Wirmer, Julia [Johann Wolfgang GoeUniversityFrankfurt, Institute for Organic Chemistry and Chemical Biology, Center for Biomolecular Magnetic Resonance (Germany); Peti, Wolfgang [Brown University, Department of Molecular Pharmacology, Physiology and Biotechnology (United States); Schwalbe, Harald [Johann Wolfgang GoeUniversityFrankfurt, Institute for Organic Chemistry and Chemical Biology, Center for Biomolecular Magnetic Resonance (Germany)], E-mail: schwalbe@nmr.uni-frankfurt.de

    2006-07-15

    The characterization of unfolded states of proteins has recently attracted considerable interest, as the residual structure present in these states may play a crucial role in determining their folding and misfolding behavior. Here, we investigated the dynamics in the denatured state of ubiquitin in 8 M urea at pH2. Under these conditions, ubiquitin does not have any detectable local residual structure, and uniform {sup 15}N relaxation rates along the sequence indicate the absence of motional restrictions caused by residual secondary structure and/or long-range interactions. A comparison of different models to predict relaxation data in unfolded proteins suggests that the subnanosecond dynamics in unfolded states depend on segmental motions only and do not show a dependence on the residue type but for proline and glycine residues.

  10. Suppression of thermal noise in a non-Markovian random velocity field

    International Nuclear Information System (INIS)

    Ueda, Masahiko

    2016-01-01

    We study the diffusion of Brownian particles in a Gaussian random velocity field with short memory. By extending the derivation of an effective Fokker–Planck equation for the Lanvegin equation with weakly colored noise to a random velocity-field problem, we find that the effect of thermal noise on particles is suppressed by the existence of memory. We also find that the renormalization effect for the relative diffusion of two particles is stronger than that for single-particle diffusion. The results are compared with those of molecular dynamics simulations. (paper: classical statistical mechanics, equilibrium and non-equilibrium)

  11. Thermally induced high frequency random amplitude fatigue damage at sharp notches

    International Nuclear Information System (INIS)

    Lewis, M.W.J.

    1992-01-01

    Experiments have been performed using the SUPERSOMITE facility to investigate the initiation and growth of fatigue cracks at the tips of sharp surface notches subjected to random thermally-induced stress. The experimental situation is complex involving plasticity, random amplitude loading and heat transfer medium/surface coupling. Crack initiation and growth prediction have been considered using the Creager and Neuber methods to compute the strain ranges in the vicinity of the notch root. Good agreement has been obtained between the experimental results and theoretical predictions. The paper reports the results of the analysis of the notch behavior

  12. Critical currents and thermally activated flux motion in high-temperature superconductors

    NARCIS (Netherlands)

    Palstra, T.T.M.; Batlogg, B.; Dover, R.B. van; Schneemeyer, L.F.; Waszczak, J.V.

    1989-01-01

    We have measured the resistance below Tc of single crystals of the high-temperature superconductors Ba2YCu3O7 and Bi2.2Sr2Ca0.8Cu2O8+δ in magnetic fields up to 12 T. The resistive transition of both compounds is dominated by intrinsic dissipation which is thermally activated, resulting in an

  13. Thermally driven ratchet motion of a skyrmion microcrystal and topological magnon Hall effect

    NARCIS (Netherlands)

    Mochizuki, M.; Yu, X.Z.; Seki, S.; Kanazawa, N.; Koshibae, W.; Zang, J.; Mostovoy, M.; Tokura, Y.; Nagaosa, N.

    2014-01-01

    Spontaneously emergent chirality is an issue of fundamental importance across the natural sciences. It has been argued that a unidirectional (chiral) rotation of a mechanical ratchet is forbidden in thermal equilibrium, but becomes possible in systems out of equilibrium. Here we report our finding

  14. Prediction of broadband ground-motion time histories: Hybrid low/high-frequency method with correlated random source parameters

    Science.gov (United States)

    Liu, P.; Archuleta, R.J.; Hartzell, S.H.

    2006-01-01

    We present a new method for calculating broadband time histories of ground motion based on a hybrid low-frequency/high-frequency approach with correlated source parameters. Using a finite-difference method we calculate low- frequency synthetics (structure. We also compute broadband synthetics in a 1D velocity model using a frequency-wavenumber method. The low frequencies from the 3D calculation are combined with the high frequencies from the 1D calculation by using matched filtering at a crossover frequency of 1 Hz. The source description, common to both the 1D and 3D synthetics, is based on correlated random distributions for the slip amplitude, rupture velocity, and rise time on the fault. This source description allows for the specification of source parameters independent of any a priori inversion results. In our broadband modeling we include correlation between slip amplitude, rupture velocity, and rise time, as suggested by dynamic fault modeling. The method of using correlated random source parameters is flexible and can be easily modified to adjust to our changing understanding of earthquake ruptures. A realistic attenuation model is common to both the 3D and 1D calculations that form the low- and high-frequency components of the broadband synthetics. The value of Q is a function of the local shear-wave velocity. To produce more accurate high-frequency amplitudes and durations, the 1D synthetics are corrected with a randomized, frequency-dependent radiation pattern. The 1D synthetics are further corrected for local site and nonlinear soil effects by using a 1D nonlinear propagation code and generic velocity structure appropriate for the site’s National Earthquake Hazards Reduction Program (NEHRP) site classification. The entire procedure is validated by comparison with the 1994 Northridge, California, strong ground motion data set. The bias and error found here for response spectral acceleration are similar to the best results that have been published by

  15. Analysis of self-heating of thermally assisted spin-transfer torque magnetic random access memory

    Directory of Open Access Journals (Sweden)

    Austin Deschenes

    2016-11-01

    Full Text Available Thermal assistance has been shown to significantly reduce the required operation power for spin torque transfer magnetic random access memory (STT-MRAM. Proposed heating methods include modified material stack compositions that result in increased self-heating or external heat sources. In this work we analyze the self-heating process of a standard perpendicular magnetic anisotropy STT-MRAM device through numerical simulations in order to understand the relative contributions of Joule, thermoelectric Peltier and Thomson, and tunneling junction heating. A 2D rotationally symmetric numerical model is used to solve the coupled electro-thermal equations including thermoelectric effects and heat absorbed or released at the tunneling junction. We compare self-heating for different common passivation materials, positive and negative electrical current polarity, and different device thermal anchoring and boundaries resistance configurations. The variations considered are found to result in significant differences in maximum temperatures reached. Average increases of 3 K, 10 K, and 100 K for different passivation materials, positive and negative polarity, and different thermal anchoring configurations, respectively, are observed. The highest temperatures, up to 424 K, are obtained for silicon dioxide as the passivation material, positive polarity, and low thermal anchoring with thermal boundary resistance configurations. Interestingly it is also found that due to the tunneling heat, Peltier effect, device geometry, and numerous interfacial layers around the magnetic tunnel junction (MTJ, most of the heat is dissipated on the lower potential side of the magnetic junction. This asymmetry in heating, which has also been observed experimentally, is important as thermally assisted switching requires heating of the free layer specifically and this will be significantly different for the two polarity operations, set and reset.

  16. Randomized Clinical Trial with e-MotionalTraining® 1.0 for Social Cognition Rehabilitation in Schizophrenia

    Directory of Open Access Journals (Sweden)

    Yolanda Maroño Souto

    2018-02-01

    Full Text Available BackgroundSchizophrenia patients present deficits in social cognition (SC, emotion and social perception, theory of mind (ToM, and attributional style. This study tested the efficacy, in real clinical conditions, of a online self-training program in SC, e-Motional Training®, in comparison with treatment as usual.MethodA randomized single-blinded multicenter clinical trial was conducted with 60 schizophrenia stable outpatients. All patients (control and intervention were treated with drug therapy, case management, and individual and group psychotherapy (not focused on SC. Intervention group was treated with e-Motional Training®, an online program devised for SC rehabilitation.Statistical analysisA descriptive analysis and parametric/non-parametric tests were used to compare both groups at baseline. Analysis of covariance was used to compared post–pre changes in SC between the two interventions. If the group effect was significant, follow-up univariate test (t-test for dependent samples was carried out in each group to verify whether the effect was due to improvement in the intervention group or deterioration in the control group. We considered statistically significant differences with P < 0.05.ResultsSignificant improvements were obtained in the intervention group in emotion recognition and most ToM variables in comparison with the control group.Discussione-Motional Training® seems to be a promising online training tool for SC deficits in schizophrenia, covering the lack of similar intervention instruments in our community.

  17. From Gyroscopic to Thermal Motion: A Crossover in the Dynamics of Molecular Superrotors

    Science.gov (United States)

    Milner, A. A.; Korobenko, A.; Rezaiezadeh, K.; Milner, V.

    2015-07-01

    Localized heating of a gas by intense laser pulses leads to interesting acoustic, hydrodynamic, and optical effects with numerous applications in science and technology, including controlled wave guiding and remote atmosphere sensing. Rotational excitation of molecules can serve as the energy source for raising the gas temperature. Here, we study the dynamics of energy transfer from the molecular rotation to heat. By optically imaging a cloud of molecular superrotors, created with an optical centrifuge, we experimentally identify two separate and qualitatively different stages of its evolution. The first nonequilibrium "gyroscopic" stage is characterized by the modified optical properties of the centrifuged gas—its refractive index and optical birefringence, owing to the ultrafast directional molecular rotation, which survives tens of collisions. The loss of rotational directionality is found to overlap with the release of rotational energy to heat, which triggers the second stage of thermal expansion. The crossover between anisotropic rotational and isotropic thermal regimes is in agreement with recent theoretical predictions and our hydrodynamic calculations.

  18. From Gyroscopic to Thermal Motion: A Crossover in the Dynamics of Molecular Superrotors

    Directory of Open Access Journals (Sweden)

    A. A. Milner

    2015-09-01

    Full Text Available Localized heating of a gas by intense laser pulses leads to interesting acoustic, hydrodynamic, and optical effects with numerous applications in science and technology, including controlled wave guiding and remote atmosphere sensing. Rotational excitation of molecules can serve as the energy source for raising the gas temperature. Here, we study the dynamics of energy transfer from the molecular rotation to heat. By optically imaging a cloud of molecular superrotors, created with an optical centrifuge, we experimentally identify two separate and qualitatively different stages of its evolution. The first nonequilibrium “gyroscopic” stage is characterized by the modified optical properties of the centrifuged gas—its refractive index and optical birefringence, owing to the ultrafast directional molecular rotation, which survives tens of collisions. The loss of rotational directionality is found to overlap with the release of rotational energy to heat, which triggers the second stage of thermal expansion. The crossover between anisotropic rotational and isotropic thermal regimes is in agreement with recent theoretical predictions and our hydrodynamic calculations.

  19. LCoMotion - Learning, Cognition and Motion; a multicomponent cluster randomized school-based intervention aimed at increasing learning and cognition - rationale, design and methods

    DEFF Research Database (Denmark)

    Bugge, Anna; Tarp, Jakob; Ostergaard, Lars

    2014-01-01

    BACKGROUND: The aim of the study; LCoMotion - Learning, Cognition and Motion was to develop, document, and evaluate a multi-component physical activity (PA) intervention in public schools in Denmark. The primary outcome was cognitive function. Secondary outcomes were academic skills, body composi...

  20. Cerebral cortex classification by conditional random fields applied to intraoperative thermal imaging

    Directory of Open Access Journals (Sweden)

    Hoffmann Nico

    2016-09-01

    Full Text Available Intraoperative thermal neuroimaging is a novel intraoperative imaging technique for the characterization of perfusion disorders, neural activity and other pathological changes of the brain. It bases on the correlation of (sub-cortical metabolism and perfusion with the emitted heat of the cortical surface. In order to minimize required computational resources and prevent unwanted artefacts in subsequent data analysis workflows foreground detection is a important preprocessing technique to differentiate pixels representing the cerebral cortex from background objects. We propose an efficient classification framework that integrates characteristic dynamic thermal behaviour into this classification task to include additional discriminative features. The first stage of our framework consists of learning this representation of characteristic thermal time-frequency behaviour. This representation models latent interconnections in the time-frequency domain that cover specific, yet a priori unknown, thermal properties of the cortex. In a second stage these features are then used to classify each pixel’s state with conditional random fields. We quantitatively evaluate several approaches to learning high-level features and their impact to the overall prediction accuracy. The introduction of high-level features leads to a significant accuracy improvement compared to a baseline classifier.

  1. A randomized trial of prewarming on patient satisfaction and thermal comfort in outpatient surgery.

    Science.gov (United States)

    Akhtar, Zohaib; Hesler, Brian D; Fiffick, Alexa N; Mascha, Edward J; Sessler, Daniel I; Kurz, Andrea; Ayad, Sabry; Saager, Leif

    2016-09-01

    To test the primary hypothesis that forced-air prewarming improves patient satisfaction after outpatient surgery and to evaluate the effect on core temperature and thermal comfort. Prospective randomized controlled trial. Preoperative area, operating room, and postanesthesia care unit. A total of 115 patients aged 18 to 75 years with American Society of Anesthesiologists status thermal comfort via visual analog scales. Data from 102 patients were included in the final analysis. Prewarming did not significantly reduce redistribution hypothermia, with prewarmed minus not prewarmed core temperature differing by only 0.18°C (95% confidence interval [CI], -0.001 to 0.37) during the initial hour of anesthesia (P=.052). Prewarming increased the mean EVAN-G satisfaction score, although not significantly, with an overall difference (prewarmed minus not prewarmed) of 5.6 (95% CI, -0.9 to 12.2; P=.09). Prewarming increased thermal comfort, with an overall difference of 6.6 mm (95% CI, 1.0-12.9; P=.02). Active prewarming increased thermal comfort but did not significantly reduce redistribution hypothermia or improve postoperative patient satisfaction. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Application of a model to investigate the effective thermal conductivity of randomly packed fusion pebble beds

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiaoliang; Zheng, Jie; Chen, Hongli, E-mail: hlchen1@ustc.edu.cn

    2016-05-15

    In our precious study, a prediction model, which calculates the effective thermal conductivity k{sub eff} of mono-sized pebble beds, has been developed and validated. Based on this model, here the effects of these influencing factors such as pebble size, thermal radiation, contact area, filling gas, gas flow, gas pressure, etc. on the k{sub eff} of randomly packed fusion pebble beds are studied and analyzed. The pebble beds investigated include Li{sub 4}SiO{sub 4}, Li{sub 2}ZrO{sub 3}, Li{sub 2}TiO{sub 3}, Li{sub 2}O, Be and BeO pebble beds. In the current study, many important and meaningful conclusions are derived and some of them are similar to the existing research results. Particularly, some critters that under which conditions the effect of some influencing factors can be neglected or should be considered are also presented.

  3. Randomized quasi-Monte Carlo simulation of fast-ion thermalization

    International Nuclear Information System (INIS)

    Höök, L J; Johnson, T; Hellsten, T

    2012-01-01

    This work investigates the applicability of the randomized quasi-Monte Carlo method for simulation of fast-ion thermalization processes in fusion plasmas, e.g. for simulation of neutral beam injection and radio frequency heating. In contrast to the standard Monte Carlo method, the quasi-Monte Carlo method uses deterministic numbers instead of pseudo-random numbers and has a statistical weak convergence close to O(N -1 ), where N is the number of markers. We have compared different quasi-Monte Carlo methods for a neutral beam injection scenario, which is solved by many realizations of the associated stochastic differential equation, discretized with the Euler-Maruyama scheme. The statistical convergence of the methods is measured for time steps up to 2 14 . (paper)

  4. Randomized quasi-Monte Carlo simulation of fast-ion thermalization

    Science.gov (United States)

    Höök, L. J.; Johnson, T.; Hellsten, T.

    2012-01-01

    This work investigates the applicability of the randomized quasi-Monte Carlo method for simulation of fast-ion thermalization processes in fusion plasmas, e.g. for simulation of neutral beam injection and radio frequency heating. In contrast to the standard Monte Carlo method, the quasi-Monte Carlo method uses deterministic numbers instead of pseudo-random numbers and has a statistical weak convergence close to {O}(N^{-1}) , where N is the number of markers. We have compared different quasi-Monte Carlo methods for a neutral beam injection scenario, which is solved by many realizations of the associated stochastic differential equation, discretized with the Euler-Maruyama scheme. The statistical convergence of the methods is measured for time steps up to 214.

  5. Thermal SiO as a probe of high velocity motions in regions of star formation

    International Nuclear Information System (INIS)

    Downes, D.; Genzel, R.; Hjalmarson, A.; Nyman, L.A.; Roennaeng, B.

    1982-01-01

    New observations of the v = 0, J = = 2→1 line of SiO at 86.8 GHz show a close association of the thermal SiO emission and infrared and maser sources in regions of star formation. In addition to SiO emission with low velocity dispersion (Δν -1 ), we report the first detection of high velocity (''plateau'') emission toward W49 and W51. The low velocity SiO component may come from the core of the molecular cloud which contains the infrared and maser sources. The ''plateau'' may indicate mass clusters. In Orion KL, the positional centroid of the high velocity SiO emission (Vertical BarΔνVertical Bar> or =20 km s -1 ) is near that of the component we identify as the ''18 km s -1 flow''. However, the centriods of the blue- and redshifted wings are displaced from each other by a few arcseconds, to the NW and NE of the position of the 18 km s -1 component. The mass-loss rates of the high velocity flow and the 18 km s -1 flow are similar

  6. The effects of complex exercise on shoulder range of motion and pain for women with breast cancer-related lymphedema: a single-blind, randomized controlled trial.

    Science.gov (United States)

    Park, Jin-Hyuck

    2017-07-01

    This study was to investigate the effects of complex exercise on shoulder range of motion and pain for women with breast cancer-related lymphedema. 69 women participated in this study and then they were randomly allocated to complex exercise group (n = 35) or the conventional decongestive therapy group (n = 34). All subjects received 8 sessions for 4 weeks. To identify the effects on shoulder range of motion and pain, goniometer and visual analog scale were used, respectively. The outcome measurements were performed before and after the 4 week intervention. After 4 weeks, complex exercise group had greater improvements in shoulder range of motion and pain compared with the conventional decongestive therapy group (p women with breast cancer-related lymphedema. Complex exercise would be useful to improve shoulder range of motion and pain of the women with breast cancer-related lymphedema.

  7. Penetration of steady fluid motions into an outer stable layer excited by MHD thermal convection in rotating spherical shells

    Science.gov (United States)

    Takehiro, Shin-ichi; Sasaki, Youhei

    2018-03-01

    Penetration of steady magneto-hydrodynamic (MHD) disturbances into an upper strongly stratified stable layer excited by MHD thermal convection in rotating spherical shells is investigated. The theoretical model proposed by Takehiro (2015) is reexamined in the case of steady fluid motion below the bottom boundary. Steady disturbances penetrate into a density stratified MHD fluid existing in the semi-infinite region in the vertical direction. The axis of rotation of the system is tilted with respect to the vertical. The basic magnetic field is uniform and may be tilted with respect to the vertical and the rotation axis. Linear dispersion relation shows that the penetration distance with zero frequency depends on the amplitude of Alfvén wave speed. When Alfvén wave speed is small, viscous diffusion becomes dominant and penetration distance is similar to the horizontal scale of the disturbance at the lower boundary. In contrast, when Alfvén wave speed becomes larger, disturbance can penetrate deeper, and penetration distance becomes proportional to the Alfvén wave speed and inversely proportional to the geometric average of viscous and magnetic diffusion coefficients and to the total horizontal wavenumber. The analytic expression of penetration distance is in good agreement with the extent of penetration of mean zonal flow induced by finite amplitude convection in a rotating spherical shell with an upper stably stratified layer embedded in an axially uniform basic magnetic field. The theory expects that the stable layer suggested in the upper part of the outer core of the earth could be penetrated completely by mean zonal flows excited by thermal/compositional convection developing below the stable layer.

  8. From Random Walks to Brownian Motion, from Diffusion to Entropy: Statistical Principles in Introductory Physics

    Science.gov (United States)

    Reeves, Mark

    2014-03-01

    Entropy changes underlie the physics that dominates biological interactions. Indeed, introductory biology courses often begin with an exploration of the qualities of water that are important to living systems. However, one idea that is not explicitly addressed in most introductory physics or biology textbooks is dominant contribution of the entropy in driving important biological processes towards equilibrium. From diffusion to cell-membrane formation, to electrostatic binding in protein folding, to the functioning of nerve cells, entropic effects often act to counterbalance deterministic forces such as electrostatic attraction and in so doing, allow for effective molecular signaling. A small group of biology, biophysics and computer science faculty have worked together for the past five years to develop curricular modules (based on SCALEUP pedagogy) that enable students to create models of stochastic and deterministic processes. Our students are first-year engineering and science students in the calculus-based physics course and they are not expected to know biology beyond the high-school level. In our class, they learn to reduce seemingly complex biological processes and structures to be described by tractable models that include deterministic processes and simple probabilistic inference. The students test these models in simulations and in laboratory experiments that are biologically relevant. The students are challenged to bridge the gap between statistical parameterization of their data (mean and standard deviation) and simple model-building by inference. This allows the students to quantitatively describe realistic cellular processes such as diffusion, ionic transport, and ligand-receptor binding. Moreover, the students confront ``random'' forces and traditional forces in problems, simulations, and in laboratory exploration throughout the year-long course as they move from traditional kinematics through thermodynamics to electrostatic interactions. This talk

  9. Simulation of Field Dependence of Critical Current Densities of Bulk High Tc Superconducting Materials regarding Thermally Activated Flux Motion

    Science.gov (United States)

    Santosh, M.; Naik, S. Pavan Kumar; Koblischka, M. R.

    2017-07-01

    In the upcoming generation, bulk high temperature superconductors (HTS) will play a crucial and a promising role in numerous industrial applications ranging from Maglev trains to magnetic resonance imaging, etc. Especially, the bulk HTS as permanent magnets are suitable due to the fact that they can trap magnetic fields being several orders of magnitude higher than those of the best hard ferromagnets. The bulk HTS LREBa2Cu3O7-δ (LREBCO or LRE-123, LRE: Y, Gd, etc.,) materials could obtain very powerful compact superconducting super-magnets, which can be operated at the cheaper liquid nitrogen temperature or below due to higher critical temperatures (i.e., ∼90 K). As a result, the new advanced technology can be utilized in a more attractive manner for a variety of technological and medical applications which have the capacity to revolutionize the field. An understanding of the magnetic field dependence of the critical current density (J c(H)) is important to develop better adapted materials. To achieve this goal, a variety of Jc (H) behaviours of bulk LREBCO samples were modelled regarding thermally activated flux motion. In essence, the Jc (H) curves follows a certain criterion where an exponential model is applied. However, to fit the complete Jc (H) curve of the LRE-123 samples an unique model is necessary to explain the behavior at low and high fields. The modelling of the various superconducting materials could be understood in terms of the pinning mechanisms.

  10. Harmonic motion imaging for focused ultrasound (HMIFU): a fully integrated technique for sonication and monitoring of thermal ablation in tissues

    International Nuclear Information System (INIS)

    Maleke, C; Konofagou, E E

    2008-01-01

    FUS (focused ultrasound), or HIFU (high-intensity-focused ultrasound) therapy, a minimally or non-invasive procedure that uses ultrasound to generate thermal necrosis, has been proven successful in several clinical applications. This paper discusses a method for monitoring thermal treatment at different sonication durations (10 s, 20 s and 30 s) using the amplitude-modulated (AM) harmonic motion imaging for focused ultrasound (HMIFU) technique in bovine liver samples in vitro. The feasibility of HMI for characterizing mechanical tissue properties has previously been demonstrated. Here, a confocal transducer, combining a 4.68 MHz therapy (FUS) and a 7.5 MHz diagnostic (pulse-echo) transducer, was used. The therapy transducer was driven by a low-frequency AM continuous signal at 25 Hz, producing a stable harmonic radiation force oscillating at the modulation frequency. A pulser/receiver was used to drive the pulse-echo transducer at a pulse repetition frequency (PRF) of 5.4 kHz. Radio-frequency (RF) signals were acquired using a standard pulse-echo technique. The temperature near the ablation region was simultaneously monitored. Both RF signals and temperature measurements were obtained before, during and after sonication. The resulting axial tissue displacement was estimated using one-dimensional cross correlation. When temperature at the focal zone was above 48 deg. C during heating, the coagulation necrosis occurred and tissue damage was irreversible. The HMI displacement profiles in relation to the temperature and sonication durations were analyzed. At the beginning of heating, the temperature at the focus increased sharply, while the tissue stiffness decreased resulting in higher HMI displacements. This was confirmed by an increase of 0.8 μm deg. C -1 (r = 0.93, p -1 , r = -0.92, p -1 , prior to and after lesion formation in seven bovine liver samples, respectively. This technique was thus capable of following the protein-denatured lesion formation based on the

  11. A Double-Blind Placebo-Controlled Randomized Clinical Trial With Magnesium Oxide to Reduce Intrafraction Prostate Motion for Prostate Cancer Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Lips, Irene M., E-mail: i.m.lips@umcutrecht.nl [Department of Radiation Oncology, University Medical Center Utrecht, Utrecht (Netherlands); Gils, Carla H. van [Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht (Netherlands); Kotte, Alexis N.T.J. [Department of Radiation Oncology, University Medical Center Utrecht, Utrecht (Netherlands); Leerdam, Monique E. van [Department of Gastroenterology and Hepatology, Erasmus University Medical Center, Rotterdam (Netherlands); Franken, Stefan P.G.; Heide, Uulke A. van der; Vulpen, Marco van [Department of Radiation Oncology, University Medical Center Utrecht, Utrecht (Netherlands)

    2012-06-01

    Purpose: To investigate whether magnesium oxide during external-beam radiotherapy for prostate cancer reduces intrafraction prostate motion in a double-blind, placebo-controlled randomized trial. Methods and Materials: At the Department of Radiotherapy, prostate cancer patients scheduled for intensity-modulated radiotherapy (77 Gy in 35 fractions) using fiducial marker-based position verification were randomly assigned to receive magnesium oxide (500 mg twice a day) or placebo during radiotherapy. The primary outcome was the proportion of patients with clinically relevant intrafraction prostate motion, defined as the proportion of patients who demonstrated in {>=}50% of the fractions an intrafraction motion outside a range of 2 mm. Secondary outcome measures included quality of life and acute toxicity. Results: In total, 46 patients per treatment arm were enrolled. The primary endpoint did not show a statistically significant difference between the treatment arms with a percentage of patients with clinically relevant intrafraction motion of 83% in the magnesium oxide arm as compared with 80% in the placebo arm (p = 1.00). Concerning the secondary endpoints, exploratory analyses demonstrated a trend towards worsened quality of life and slightly more toxicity in the magnesium oxide arm than in the placebo arm; however, these differences were not statistically significant. Conclusions: Magnesium oxide is not effective in reducing the intrafraction prostate motion during external-beam radiotherapy, and therefore there is no indication to use it in clinical practice for this purpose.

  12. MMRW-BOOKS, Legacy books on slowing down, thermalization, particle transport theory, random processes in reactors

    International Nuclear Information System (INIS)

    Williams, M.M.R.

    2007-01-01

    Description: Prof. M.M..R Williams has now released three of his legacy books for free distribution: 1 - M.M.R. Williams: The Slowing Down and Thermalization of Neutrons, North-Holland Publishing Company - Amsterdam, 582 pages, 1966. Content: Part I - The Thermal Energy Region: 1. Introduction and Historical Review, 2. The Scattering Kernel, 3. Neutron Thermalization in an Infinite Homogeneous Medium, 4. Neutron Thermalization in Finite Media, 5. The Spatial Dependence of the Energy Spectrum, 6. Reactor Cell Calculations, 7. Synthetic Scattering Kernels. Part II - The Slowing Down Region: 8. Scattering Kernels in the Slowing Down Region, 9. Neutron Slowing Down in an Infinite Homogeneous Medium, 10.Neutron Slowing Down and Diffusion. 2 - M.M.R. Williams: Mathematical Methods in Particle Transport Theory, Butterworths, London, 430 pages, 1971. Content: 1 The General Problem of Particle Transport, 2 The Boltzmann Equation for Gas Atoms and Neutrons, 3 Boundary Conditions, 4 Scattering Kernels, 5 Some Basic Problems in Neutron Transport and Rarefied Gas Dynamics, 6 The Integral Form of the Transport Equation in Plane, Spherical and Cylindrical Geometries, 7 Exact Solutions of Model Problems, 8 Eigenvalue Problems in Transport Theory, 9 Collision Probability Methods, 10 Variational Methods, 11 Polynomial Approximations. 3 - M.M.R. Williams: Random Processes in Nuclear Reactors, Pergamon Press Oxford New York Toronto Sydney, 243 pages, 1974. Content: 1. Historical Survey and General Discussion, 2. Introductory Mathematical Treatment, 3. Applications of the General Theory, 4. Practical Applications of the Probability Distribution, 5. The Langevin Technique, 6. Point Model Power Reactor Noise, 7. The Spatial Variation of Reactor Noise, 8. Random Phenomena in Heterogeneous Reactor Systems, 9. Associated Fluctuation Problems, Appendix: Noise Equivalent Sources. Note to the user: Prof. M.M.R Williams owns the copyright of these books and he authorises the OECD/NEA Data Bank

  13. Human tracking in thermal images using adaptive particle filters with online random forest learning

    Science.gov (United States)

    Ko, Byoung Chul; Kwak, Joon-Young; Nam, Jae-Yeal

    2013-11-01

    This paper presents a fast and robust human tracking method to use in a moving long-wave infrared thermal camera under poor illumination with the existence of shadows and cluttered backgrounds. To improve the human tracking performance while minimizing the computation time, this study proposes an online learning of classifiers based on particle filters and combination of a local intensity distribution (LID) with oriented center-symmetric local binary patterns (OCS-LBP). Specifically, we design a real-time random forest (RF), which is the ensemble of decision trees for confidence estimation, and confidences of the RF are converted into a likelihood function of the target state. First, the target model is selected by the user and particles are sampled. Then, RFs are generated using the positive and negative examples with LID and OCS-LBP features by online learning. The learned RF classifiers are used to detect the most likely target position in the subsequent frame in the next stage. Then, the RFs are learned again by means of fast retraining with the tracked object and background appearance in the new frame. The proposed algorithm is successfully applied to various thermal videos as tests and its tracking performance is better than those of other methods.

  14. Static magnetism and thermal switching in randomly oriented L10 FePt thin films

    Science.gov (United States)

    Lisfi, A.; Pokharel, S.; Alqarni, A.; Akioya, O.; Morgan, W.; Wuttig, M.

    2018-05-01

    Static magnetism and thermally activated magnetic relaxation were investigated in granular FePt films (20 nm-200 nm thick) with random magnetic anisotropy through hysteresis loop, torque curve and magnetization time dependence measurements. While the magnetism of thicker film (200 nm thick) is dominated by a single switching of the ordered L10 phase, thinner film (20 nm) displays a double switching, which is indicative of the presence of the disordered cubic phase. The pronounced behavior of double switching in thinner film suggests that the film grain boundary is composed of soft cubic magnetic phase. The magnetic relaxation study reveals that magnetic viscosity S of the films is strongly dependent on the external applied field and exhibits a maximum value (12 kAm) around the switching field and a vanishing behavior at low (1 kOe) and large (12 kOe) fields. The activation volume of the thermal switching was found to be much smaller than the physical volume of the granular structure due to the incoherent rotation mode of the magnetization reversal mechanism, which is established to be domain wall nucleation.

  15. Thermal analysis studies of doping effects on the conformational motions of polymer chains in solid solutions with lasing molecules

    Science.gov (United States)

    Kalogeras, Ioannis M.; Pallikari, Fotini; Vassilikou-Dova, Aglaia; Neagu, Eugen R.

    2007-05-01

    The advancement of the solid-state dye laser performance largely depends on the systematic study of the dye-matrix interactions at the nanoscopic scale. The current work deals with blends of a comparatively inert dye host, poly(methyl methacrylate) (PMMA), with nonionic/apolar (substituted perylenes) and ionic/polar (rhodamine 6G, pyrromethene 567) dyes at ≈10-4 mol L-1 loading. Differential scanning calorimetry (DSC) and thermally stimulated currents (TSC) were used to explore the relative strength of inter- and intramolecular guest-host interactions by monitoring blending-induced modifications of the high-temperature signals: the segmental relaxation, the space-charge relaxation, and the liquid-liquid transition. Both techniques revealed the antiplasticizing role of the oligomeric organics on the relaxation dynamics of polymer segments, evidenced by clear glass-transition temperature upshifts. It becomes apparent that this effect is independent of the size, polarity, and ionicity of the dopant, signifying a common mechanism underway. It is suggested that, at least for the dyes under investigation, the chromophores simply fill the voids within the matrix, imposing strong steric hindrances on the rearrangement of the long-range structure. A comparison between the present results and earlier low-temperature dielectric data reveals that the large-scale relaxation dynamics show stronger perturbations due to blending, in comparison to the localized rotational motion of the pendant groups. DSC provided estimates for the unconverted monomer percentages in the solid blends. These were also determined more accurately by nuclear magnetic resonance (NMR), which additionally confirmed that the tacticity of the chains is not affected by the presence of the dye.

  16. Quantifying and Characterizing Tonic Thermal Pain Across Subjects From EEG Data Using Random Forest Models.

    Science.gov (United States)

    Vijayakumar, Vishal; Case, Michelle; Shirinpour, Sina; He, Bin

    2017-12-01

    Effective pain assessment and management strategies are needed to better manage pain. In addition to self-report, an objective pain assessment system can provide a more complete picture of the neurophysiological basis for pain. In this study, a robust and accurate machine learning approach is developed to quantify tonic thermal pain across healthy subjects into a maximum of ten distinct classes. A random forest model was trained to predict pain scores using time-frequency wavelet representations of independent components obtained from electroencephalography (EEG) data, and the relative importance of each frequency band to pain quantification is assessed. The mean classification accuracy for predicting pain on an independent test subject for a range of 1-10 is 89.45%, highest among existing state of the art quantification algorithms for EEG. The gamma band is the most important to both intersubject and intrasubject classification accuracy. The robustness and generalizability of the classifier are demonstrated. Our results demonstrate the potential of this tool to be used clinically to help us to improve chronic pain treatment and establish spectral biomarkers for future pain-related studies using EEG.

  17. Lagrangian modelling of plankton motion: From deceptively simple random walks to Fokker-Planck and back again

    DEFF Research Database (Denmark)

    Visser, Andre

    2008-01-01

    The movement of plankton, either by turbulent mixing or their own inherent motility, can be simulated in a Lagrangian framework as a random walk. Validation of random walk simulations is essential. There is a continuum of mathematically valid stochastic integration schemes upon which random walk...

  18. Effect of magnesium oxide on interfraction prostate motion and rectal filling in prostate cancer radiotherapy. Analysis of a randomized clinical trial

    International Nuclear Information System (INIS)

    Harder, Annemarie M. den; Kotte, Alexis N.T.J.; Vulpen, Marco van; Lips, Irene M.; Gils, Carla H. van

    2014-01-01

    To investigate whether magnesium oxide reduces the interfraction motion of the prostate and the amount of rectal filling and rectal gas, which influences prostate position during radiotherapy for prostate cancer. From December 2008 to February 2010, 92 prostate cancer patients scheduled for intensity-modulated radiotherapy (77 Gy in 35 fractions) using fiducial marker-based position verification were randomly assigned to receive magnesium oxide (500 mg twice a day) or placebo during radiotherapy. In a previous study, we investigated the effect on intrafraction motion and did not find a difference between the treatment arms. Here, we compared the interfraction prostate motion between the two treatment arms as well as the amount of rectal filling and rectal air pockets using pretreatment planning computed tomography and magnetic resonance imaging scans. There was no statistically significant difference between the treatment arms in translation and rotation of the prostate between treatment fractions, except for the rotation around the cranial caudal axis. However, the difference was less than 1 and therefore considered not clinically relevant. There was no significant difference in the amount of rectal filling and rectal air pockets between the treatment arms. Magnesium oxide is not effective in reducing the interfraction prostate motion or the amount of rectal filling and rectal gas during external-beam radiotherapy. Therefore, magnesium oxide is not recommended in clinical practice for these purposes. (orig.) [de

  19. Influence of vestibular rehabilitation on neck pain and cervical range of motion among patients with whiplash-associated disorder: a randomized controlled trial.

    Science.gov (United States)

    Hansson, Eva Ekvall; Persson, Liselott; Malmström, Eva Maj

    2013-09-01

    To describe how vestibular rehabilitation influences pain and range of motion among patients with whiplash-associated disorder and dizziness, and to describe whether pain or range of motion correlated with balance performance or self-perceived dizziness handicap. A total of 29 patients, 20 women and 9 men, age range 22-76 years. Patients with whiplash-associated disorder and dizziness were randomized to either intervention (vestibular rehabilitation) or control. Neck pain intensity, cervical range of motion (CROM), balance and self-perceived dizziness handicap were measured at baseline, 6 weeks and 3 months. There were no differences in neck pain intensity or CROM between the 2 groups either at baseline, 6 weeks or 3 months (p = 0.10-0.89). At baseline, neck pain intensity correlated with CROM (-0.406) and self-perceived dizziness handicap (0.492). CROM correlated with self-perceived dizziness handicap and with 1 balance measure (-0.432). Neck pain intensity did not correlate with balance performance (-0.188-0.049). Neck pain intensity and CROM was not influenced by vestibular rehabilitation. Importantly, the programme did not appear to increase pain or decrease neck motion, as initially thought. Neck pain intensity and CROM correlated with self-perceived dizziness handicap. CROM also correlated with 1 balance measure.

  20. A randomized, double-blind, crossover comparison of novel continuous bed motion versus traditional bed position whole-body PET/CT imaging

    International Nuclear Information System (INIS)

    Schatka, Imke; Weiberg, Desiree; Reichelt, Stephanie; Owsianski-Hille, Nicole; Derlin, Thorsten; Berding, Georg; Bengel, Frank M.

    2016-01-01

    Continuous bed motion has recently been introduced for whole-body PET/CT, and represents a paradigm shift towards individualized and flexible acquisition without the limitations of bed position-based planning. Increased patient comfort due to lack of abrupt table position changes may be another albeit still unproven advantage. For robust clinical implementation, image quality and quantitative accuracy should at least be equal to the prior standard of bed position-based step-and-shoot imaging. The study included 68 consecutive patients referred for whole-body PET/CT for various malignancies. The patients underwent traditional step-and-shoot and novel continuous bed motion acquisition in the same session in a randomized crossover design. The patients and two independent observers were blinded to the sequence of scan techniques. Patient comfort/satisfaction was examined using a standardized questionnaire. SUVs were compared for reference tissue (liver, muscle) and tumour lesions. PET image quality and misalignment with CT images were evaluated on a scale of 1 - 4. Patients preferred continuous bed motion over step-and-shoot (P = 0.0001). It was considered to be more relaxing (38 % vs. 8 %), quieter (34 % vs. 8 %), and more fluid (64 % vs. 8 %). Image quality, SUV and CT misalignment did not differ between the techniques. Continuous bed motion resulted in better end-plane image quality (P < 0.0001). Regardless of the technique, second examinations had significantly higher tumour lesion SUVmax values (P = 0.0002), and a higher CT misalignment score (P = 0.0017). Oncological PET/CT with continuous bed motion enhances patient comfort and is associated with image quality at least comparable to that with traditional bed position-based step-and-shoot acquisition. (orig.)

  1. A randomized, double-blind, crossover comparison of novel continuous bed motion versus traditional bed position whole-body PET/CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Schatka, Imke [Hannover Medical School, Department of Nuclear Medicine, Hannover (Germany); Charite, Department of Nuclear Medicine, Berlin (Germany); Weiberg, Desiree; Reichelt, Stephanie; Owsianski-Hille, Nicole; Derlin, Thorsten; Berding, Georg; Bengel, Frank M. [Hannover Medical School, Department of Nuclear Medicine, Hannover (Germany)

    2016-04-15

    Continuous bed motion has recently been introduced for whole-body PET/CT, and represents a paradigm shift towards individualized and flexible acquisition without the limitations of bed position-based planning. Increased patient comfort due to lack of abrupt table position changes may be another albeit still unproven advantage. For robust clinical implementation, image quality and quantitative accuracy should at least be equal to the prior standard of bed position-based step-and-shoot imaging. The study included 68 consecutive patients referred for whole-body PET/CT for various malignancies. The patients underwent traditional step-and-shoot and novel continuous bed motion acquisition in the same session in a randomized crossover design. The patients and two independent observers were blinded to the sequence of scan techniques. Patient comfort/satisfaction was examined using a standardized questionnaire. SUVs were compared for reference tissue (liver, muscle) and tumour lesions. PET image quality and misalignment with CT images were evaluated on a scale of 1 - 4. Patients preferred continuous bed motion over step-and-shoot (P = 0.0001). It was considered to be more relaxing (38 % vs. 8 %), quieter (34 % vs. 8 %), and more fluid (64 % vs. 8 %). Image quality, SUV and CT misalignment did not differ between the techniques. Continuous bed motion resulted in better end-plane image quality (P < 0.0001). Regardless of the technique, second examinations had significantly higher tumour lesion SUVmax values (P = 0.0002), and a higher CT misalignment score (P = 0.0017). Oncological PET/CT with continuous bed motion enhances patient comfort and is associated with image quality at least comparable to that with traditional bed position-based step-and-shoot acquisition. (orig.)

  2. Effectiveness of a School-Based Physical Activity Intervention on Cognitive Performance in Danish Adolescents: LCoMotion-Learning, Cognition and Motion - A Cluster Randomized Controlled Trial.

    Directory of Open Access Journals (Sweden)

    Jakob Tarp

    Full Text Available Physical activity is associated not only with health-related parameters, but also with cognitive and academic performance. However, no large scale school-based physical activity interventions have investigated effects on cognitive performance in adolescents. The aim of this study was to describe the effectiveness of a school-based physical activity intervention in enhancing cognitive performance in 12-14 years old adolescents.A 20 week cluster randomized controlled trial was conducted including seven intervention and seven control schools. A total of 632 students (mean (SD age: 12.9 (0.6 years completed the trial with baseline and follow-up data on primary or secondary outcomes (74% of randomized subjects. The intervention targeted physical activity during academic subjects, recess, school transportation and leisure-time. Cognitive performance was assessed using an executive functions test of inhibition (flanker task with the primary outcomes being accuracy and reaction time on congruent and incongruent trials. Secondary outcomes included mathematics performance, physical activity levels, body-mass index, waist-circumference and cardiorespiratory fitness.No significant difference in change, comparing the intervention group to the control group, was observed on the primary outcomes (p's>0.05 or mathematics skills (p>0.05. An intervention effect was found for cardiorespiratory fitness in girls (21 meters (95% CI: 4.4-38.6 and body-mass index in boys (-0.22 kg/m2 (95% CI: -0.39-0.05. Contrary to our predictions, a significantly larger change in interference control for reaction time was found in favor of the control group (5.0 milliseconds (95% CI: 0-9. Baseline to mid-intervention changes in physical activity levels did not differ significantly between groups (all p's>0.05.No evidence was found for effectiveness of a 20-week multi-faceted school-based physical activity intervention for enhancing executive functioning or mathematics skills compared

  3. Effectiveness of a School-Based Physical Activity Intervention on Cognitive Performance in Danish Adolescents: LCoMotion-Learning, Cognition and Motion - A Cluster Randomized Controlled Trial.

    Science.gov (United States)

    Tarp, Jakob; Domazet, Sidsel Louise; Froberg, Karsten; Hillman, Charles H; Andersen, Lars Bo; Bugge, Anna

    2016-01-01

    Physical activity is associated not only with health-related parameters, but also with cognitive and academic performance. However, no large scale school-based physical activity interventions have investigated effects on cognitive performance in adolescents. The aim of this study was to describe the effectiveness of a school-based physical activity intervention in enhancing cognitive performance in 12-14 years old adolescents. A 20 week cluster randomized controlled trial was conducted including seven intervention and seven control schools. A total of 632 students (mean (SD) age: 12.9 (0.6) years) completed the trial with baseline and follow-up data on primary or secondary outcomes (74% of randomized subjects). The intervention targeted physical activity during academic subjects, recess, school transportation and leisure-time. Cognitive performance was assessed using an executive functions test of inhibition (flanker task) with the primary outcomes being accuracy and reaction time on congruent and incongruent trials. Secondary outcomes included mathematics performance, physical activity levels, body-mass index, waist-circumference and cardiorespiratory fitness. No significant difference in change, comparing the intervention group to the control group, was observed on the primary outcomes (p's>0.05) or mathematics skills (p>0.05). An intervention effect was found for cardiorespiratory fitness in girls (21 meters (95% CI: 4.4-38.6) and body-mass index in boys (-0.22 kg/m2 (95% CI: -0.39-0.05). Contrary to our predictions, a significantly larger change in interference control for reaction time was found in favor of the control group (5.0 milliseconds (95% CI: 0-9). Baseline to mid-intervention changes in physical activity levels did not differ significantly between groups (all p's>0.05). No evidence was found for effectiveness of a 20-week multi-faceted school-based physical activity intervention for enhancing executive functioning or mathematics skills compared to a

  4. Efficacy of manual and manipulative therapy in the perception of pain and cervical motion in patients with tension-type headache: a randomized, controlled clinical trial.

    Science.gov (United States)

    Espí-López, Gemma V; Gómez-Conesa, Antonia

    2014-03-01

    The purpose of this study was to evaluate the efficacy of manipulative and manual therapy treatments with regard to pain perception and neck mobility in patients with tension-type headache. A randomized clinical trial was conducted on 84 adults diagnosed with tension-type headache. Eighty-four subjects were enrolled in this study: 68 women and 16 men. Mean age was 39.76 years, ranging from 18 to 65 years. A total of 57.1% were diagnosed with chronic tension-type headache and 42.9% with tension-type headache. Participants were divided into 3 treatment groups (manual therapy, manipulative therapy, a combination of manual and manipulative therapy) and a control group. Four treatment sessions were administered during 4 weeks, with posttreatment assessment and follow-up at 1 month. Cervical ranges of motion pain perception, and frequency and intensity of headaches were assessed. All 3 treatment groups showed significant improvements in the different dimensions of pain perception. Manual therapy and manipulative treatment improved some cervical ranges of motion. Headache frequency was reduced with manipulative treatment (P treatment reported improvement after the treatment (P treatment and at follow-up with manipulative therapy (P treatment (P treatments, administered both separately and combined together, showed efficacy for patients with tension-type headache with regard to pain perception. As for cervical ranges of motion, treatments produced greater effect when separately administered.

  5. Fractional Brownian motions via random walk in the complex plane and via fractional derivative. Comparison and further results on their Fokker-Planck equations

    International Nuclear Information System (INIS)

    Jumarie, Guy

    2004-01-01

    There are presently two different models of fractional Brownian motions available in the literature: the Riemann-Liouville fractional derivative of white noise on the one hand, and the complex-valued Brownian motion of order n defined by using a random walk in the complex plane, on the other hand. The paper provides a comparison between these two approaches, and in addition, takes this opportunity to contribute some complements. These two models are more or less equivalent on the theoretical standpoint for fractional order between 0 and 1/2, but their practical significances are quite different. Otherwise, for order larger than 1/2, the fractional derivative model has no counterpart in the complex plane. These differences are illustrated by an example drawn from mathematical finance. Taylor expansion of fractional order provides the expression of fractional difference in terms of finite difference, and this allows us to improve the derivation of Fokker-Planck equation and Kramers-Moyal expansion, and to get more insight in their relation with stochastic differential equations of fractional order. In the case of multi-fractal systems, the Fokker-Planck equation can be solved by using path integrals, and the fractional dynamic equations of the state moments of the stochastic system can be easily obtained. By combining fractional derivative and complex white noise of order n, one obtains a family of complex-valued fractional Brownian motions which exhibits long-range dependence. The conclusion outlines suggestions for further research, mainly regarding Lorentz transformation of fractional noises

  6. Center of Pressure Motion After Calf Vibration Is More Random in Fallers Than Non-fallers: Prospective Study of Older Individuals

    Directory of Open Access Journals (Sweden)

    Wolbert van den Hoorn

    2018-03-01

    dynamic re-weighting is required. During this period fallers exhibited more random CoP motion, which could result from a reduced ability to control balance and/or a reduced ability to dynamically reweight proprioceptive information. These results show that non-linear measures of balance provide evidence for deficits in balance control in people who go on to fall in the following 12 months.

  7. NAK WP-cave project: Thermally induced convective motion in groundwater in the near field of the WP-cave after filling and closure

    International Nuclear Information System (INIS)

    Hopkirk, R.J.

    1989-04-01

    The thermal convective motion induced in groundwater due to the decay heat generated by the high-level waste in the WP-Cave has been studied by means of coupled thermo-hydraulic numerical models. The WPC concept is proposed as an alternative to the KBS-3 repository concept for construction in crystalline rock. However, in the absence of specific site fissure data, the rock mass has been modelled as a quasi-porous medium. The repository was assumed to be filled 40 years after unloading of the spent fuel. For a further 100 years the whole repository is cooled, before being backfilled and sealed off. Maximum waste temperatures and the fluid fluxes crossing the backfilled bentonite diffusion barrier were monitored to 3000 years after fuel unloading. At the same time, the effects of the hydraulic cage and of a highly permeable rock zone beneath the central storage volume on the induced fluid flows have been assessed. (orig.)

  8. Fractional Nonablative 1540 nm Laser Resurfacing for Thermal Burn Scars: A Randomized Controlled Trial

    DEFF Research Database (Denmark)

    Haedersdal, M.; Moreau, K.E.R.; Beyer, D.M.

    2009-01-01

    Background and Objective: Burn scars cause permanent and disfiguring problems for many patients and limited treatments are available. Nonablative fractional lasers induce a wound healing response, which may lead to remodeling of burn sear texture. This randomized trial evaluates efficacy and adve......Background and Objective: Burn scars cause permanent and disfiguring problems for many patients and limited treatments are available. Nonablative fractional lasers induce a wound healing response, which may lead to remodeling of burn sear texture. This randomized trial evaluates efficacy...

  9. The efficacy of interactive, motion capture-based rehabilitation on functional outcomes in an inpatient stroke population: a randomized controlled trial.

    Science.gov (United States)

    Cannell, John; Jovic, Emelyn; Rathjen, Amy; Lane, Kylie; Tyson, Anna M; Callisaya, Michele L; Smith, Stuart T; Ahuja, Kiran Dk; Bird, Marie-Louise

    2018-02-01

    To compare the efficacy of novel interactive, motion capture-rehabilitation software to usual care stroke rehabilitation on physical function. Randomized controlled clinical trial. Two subacute hospital rehabilitation units in Australia. In all, 73 people less than six months after stroke with reduced mobility and clinician determined capacity to improve. Both groups received functional retraining and individualized programs for up to an hour, on weekdays for 8-40 sessions (dose matched). For the intervention group, this individualized program used motivating virtual reality rehabilitation and novel gesture controlled interactive motion capture software. For usual care, the individualized program was delivered in a group class on one unit and by rehabilitation assistant 1:1 on the other. Primary outcome was standing balance (functional reach). Secondary outcomes were lateral reach, step test, sitting balance, arm function, and walking. Participants (mean 22 days post-stroke) attended mean 14 sessions. Both groups improved (mean (95% confidence interval)) on primary outcome functional reach (usual care 3.3 (0.6 to 5.9), intervention 4.1 (-3.0 to 5.0) cm) with no difference between groups ( P = 0.69) on this or any secondary measures. No differences between the rehabilitation units were seen except in lateral reach (less affected side) ( P = 0.04). No adverse events were recorded during therapy. Interactive, motion capture rehabilitation for inpatients post stroke produced functional improvements that were similar to those achieved by usual care stroke rehabilitation, safely delivered by either a physical therapist or a rehabilitation assistant.

  10. Effectiveness of the Gaze Direction Recognition Task for Chronic Neck Pain and Cervical Range of Motion: A Randomized Controlled Pilot Study

    Directory of Open Access Journals (Sweden)

    Satoshi Nobusako

    2012-01-01

    Full Text Available We developed a mental task with gaze direction recognition (GDR by which subjects observed neck rotation of another individual from behind and attempted to recognize the direction of gaze. A randomized controlled trial was performed in test (=9 and control (=8 groups of subjects with chronic neck pain undergoing physical therapy either with or without the GDR task carried out over 12 sessions during a three-week period. Primary outcome measures were defined as the active range of motion and pain on rotation of the neck. Secondary outcome measures were reaction time (RT and response accuracy in the GDR task group. ANOVA indicated a main effect for task session and group, and interaction of session. Post hoc testing showed that the GDR task group exhibited a significant simple main effect upon session, and significant sequential improvement of neck motion and relief of neck pain. Rapid effectiveness was significant in both groups. The GDR task group had a significant session-to-session reduction of RTs in correct responses. In conclusion, the GDR task we developed provides a promising rehabilitation measure for chronic neck pain.

  11. Viscous Dissipation Effects on the Motion of Casson Fluid over an Upper Horizontal Thermally Stratified Melting Surface of a Paraboloid of Revolution: Boundary Layer Analysis

    Directory of Open Access Journals (Sweden)

    T. M. Ajayi

    2017-01-01

    Full Text Available The problem of a non-Newtonian fluid flow past an upper surface of an object that is neither a perfect horizontal/vertical nor inclined/cone in which dissipation of energy is associated with temperature-dependent plastic dynamic viscosity is considered. An attempt has been made to focus on the case of two-dimensional Casson fluid flow over a horizontal melting surface embedded in a thermally stratified medium. Since the viscosity of the non-Newtonian fluid tends to take energy from the motion (kinetic energy and transform it into internal energy, the viscous dissipation term is accommodated in the energy equation. Due to the existence of internal space-dependent heat source; plastic dynamic viscosity and thermal conductivity of the non-Newtonian fluid are assumed to vary linearly with temperature. Based on the boundary layer assumptions, suitable similarity variables are applied to nondimensionalized, parameterized and reduce the governing partial differential equations into a coupled ordinary differential equations. These equations along with the boundary conditions are solved numerically using the shooting method together with the Runge-Kutta technique. The effects of pertinent parameters are established. A significant increases in Rex1/2Cfx is guaranteed with St when magnitude of β is large. Rex1/2Cfx decreases with Ec and m.

  12. Using motion-sensor camera technology to infer seasonal activity and thermal niche of the desert tortoise (Gopherus agassizii)

    Science.gov (United States)

    Agha, Mickey; Augustine, Benjamin; Lovich, Jeffrey E.; Delaney, David F.; Sinervo, Barry; Murphy, Mason O.; Ennen, Joshua R.; Briggs, Jessica R.; Cooper, Robert J.; Price, Steven J.

    2015-01-01

    Understanding the relationships between environmental variables and wildlife activity is an important part of effective management. The desert tortoise (Gopherus agassizii), an imperiled species of arid environments in the southwest US, may have increasingly restricted windows for activity due to current warming trends. In summer 2013, we deployed 48 motion sensor cameras at the entrances of tortoise burrows to investigate the effects of temperature, sex, and day of the year on the activity of desert tortoises. Using generalized estimating equations, we found that the relative probability of activity was associated with temperature (linear and quadratic), sex, and day of the year. Sex effects showed that male tortoises are generally more active than female tortoises. Temperature had a quadratic effect, indicating that tortoise activity was heightened at a range of temperatures. In addition, we found significant support for interactions between sex and day of the year, and sex and temperature as predictors of the probability of activity. Using our models, we were able to estimate air temperatures and times (days and hours) that were associated with maximum activity during the study. Because tortoise activity is constrained by environmental conditions such as temperature, it is increasingly vital to conduct studies on how tortoises vary their activity throughout the Sonoran Desert to better understand the effects of a changing climate.

  13. Effect of magnesium oxide on interfraction prostate motion and rectal filling in prostate cancer radiotherapy. Analysis of a randomized clinical trial

    Energy Technology Data Exchange (ETDEWEB)

    Harder, Annemarie M. den; Kotte, Alexis N.T.J.; Vulpen, Marco van; Lips, Irene M. [University Medical Center Utrecht, Department of Radiation Oncology, Utrecht (Netherlands); Gils, Carla H. van [University Medical Center Utrecht, Julius Center for Health Sciences and Primary Care, Utrecht (Netherlands)

    2014-08-15

    To investigate whether magnesium oxide reduces the interfraction motion of the prostate and the amount of rectal filling and rectal gas, which influences prostate position during radiotherapy for prostate cancer. From December 2008 to February 2010, 92 prostate cancer patients scheduled for intensity-modulated radiotherapy (77 Gy in 35 fractions) using fiducial marker-based position verification were randomly assigned to receive magnesium oxide (500 mg twice a day) or placebo during radiotherapy. In a previous study, we investigated the effect on intrafraction motion and did not find a difference between the treatment arms. Here, we compared the interfraction prostate motion between the two treatment arms as well as the amount of rectal filling and rectal air pockets using pretreatment planning computed tomography and magnetic resonance imaging scans. There was no statistically significant difference between the treatment arms in translation and rotation of the prostate between treatment fractions, except for the rotation around the cranial caudal axis. However, the difference was less than 1 and therefore considered not clinically relevant. There was no significant difference in the amount of rectal filling and rectal air pockets between the treatment arms. Magnesium oxide is not effective in reducing the interfraction prostate motion or the amount of rectal filling and rectal gas during external-beam radiotherapy. Therefore, magnesium oxide is not recommended in clinical practice for these purposes. (orig.) [German] Ziel der Studie war es, zu untersuchen, ob Magnesiumoxid die interfraktionaere Bewegung und die rektale Fuellung sowie rektales Gas reduziert, was die Position der Prostata waehrend der Strahlentherapie bei Prostatakrebs beeinflusst. Von Dezember 2008 bis Februar 2010 haben 92 Prostatakrebspatienten die intensitaetsmodulierte Strahlentherapie (IMRT) mit bezugsmarkenbasierter Positionsverifikation erhalten (77 Gy in 35 Fraktionen). Sie wurden waehrend

  14. Measurement of moisture motion under a temperature gradient in a concrete for SNR-300 using thermal neutrons

    International Nuclear Information System (INIS)

    Zelinger, A.

    1975-01-01

    For describing the behavior of the moisture in the concrete of the containment of SNR-300 in a hypothetical accident parameters were determined experimentally. The method is based on transmission of thermal neutrons through a plate of concrete. When a temperature of 170 deg C was applied at one end of the plate migration of moisture and evaporation took place. This could be observed by neutron radiography giving a gross picture of moisture migration. Furthermore the intensity of the transmitted neutron beam was measured with a neutron counter. From these values profiles of the change of moisture concentration could be obtained with a spatial resolution of few millimeters. The method used is entirely different from the conventional moisture meters which use fast neutrons. From the experimental data the mass transfer coefficient of vapour, the diffusion coefficient of vapour in concrete and the porosity of the concrete could be determined

  15. The Relationship Between Engagement and Neurophysiological Measures of Attention in Motion-Controlled Video Games: A Randomized Controlled Trial.

    Science.gov (United States)

    Leiker, Amber M; Miller, Matthew; Brewer, Lauren; Nelson, Monica; Siow, Maria; Lohse, Keith

    2016-04-21

    Video games and virtual environments continue to be the subject of research in health sciences for their capacity to augment practice through user engagement. Creating game mechanics that increase user engagement may have indirect benefits on learning (ie, engaged learners are likely to practice more) and may also have direct benefits on learning (ie, for a fixed amount of practice, engaged learners show superior retention of information or skills). To manipulate engagement through the aesthetic features of a motion-controlled video game and measure engagement's influence on learning. A group of 40 right-handed participants played the game under two different conditions (game condition or sterile condition). The mechanics of the game and the amount of practice were constant. During practice, event-related potentials (ERPs) to task-irrelevant probe tones were recorded during practice as an index of participants' attentional reserve. Participants returned for retention and transfer testing one week later. Although both groups improved in the task, there was no difference in the amount of learning between the game and sterile groups, countering previous research. A new finding was a statistically significant relationship between self-reported engagement and the amplitude of the early-P3a (eP3a) component of the ERP waveform, such that participants who reported higher levels of engagement showed a smaller eP3a (beta=-.08, P=.02). This finding provides physiological data showing that engagement elicits increased information processing (reducing attentional reserve), which yields new insight into engagement and its underlying neurophysiological properties. Future studies may objectively index engagement by quantifying ERPs (specifically the eP3a) to task-irrelevant probes.

  16. A randomized clinical trial to compare the immediate effects of seated thoracic manipulation and targeted supine thoracic manipulation on cervical spine flexion range of motion and pain.

    Science.gov (United States)

    Karas, Steve; Olson Hunt, Megan J

    2014-05-01

    Randomized clinical trial. To determine the effectiveness of seated thoracic manipulation versus targeted supine thoracic manipulation on cervical spine pain and flexion range of motion (ROM). There is evidence that thoracic spine manipulation is an effective treatment for patients with cervical spine pain. This evidence includes a variety of techniques to manipulate the thoracic spine. Although each of them is effective, no research has compared techniques to determine which produces the best outcomes. A total of 39 patients with cervical spine pain were randomly assigned to either a seated thoracic manipulation or targeted supine thoracic manipulation group. Pain and flexion ROM measures were taken before and after the intervention. Pain reduction (post-treatment-pre-treatment) was significantly greater in those patients receiving the targeted supine thoracic manipulation compared to the seated thoracic manipulation (Pmanipulation group. The results of this study indicate that a targeted supine thoracic manipulation may be more effective in reducing cervical spine pain and improving cervical flexion ROM than a seated thoracic manipulation. Future studies should include a variety of patients and physical therapists (PTs) to validate our findings.

  17. Effects of massage therapy and occlusal splint therapy on mandibular range of motion in individuals with temporomandibular disorder: a randomized clinical trial.

    Science.gov (United States)

    Gomes, Cid André Fidelis de Paula; Politti, Fabiano; Andrade, Daniel Ventura; de Sousa, Dowglas Fernando Magalhães; Herpich, Carolina Marciela; Dibai-Filho, Almir Vieira; Gonzalez, Tabajara de Oliveira; Biasotto-Gonzalez, Daniela Aparecida

    2014-01-01

    The purpose of this study was to investigate the effects of massage therapy compared with occlusal splint therapy on mandibular range of motion (ROM) in individuals with temporomandibular disorder (TMD) and compare the results with ROM obtained in a group of individuals without this disorder. A blinded randomized clinical trial was conducted. Twenty-eight volunteers with TMD were randomly distributed into either a massage therapy group or an occlusal splint group. Both treatments were provided for 4 weeks. Fourteen individuals without TMD were consecutively allocated to a comparison group. Fonseca anamnestic index was used to characterize TMD and allocate the volunteers to either of the intervention groups or asymptomatic comparison group. Mandibular ROM was evaluated before and after treatment using a digital caliper. Two-way repeated-measures analysis of variance with a post hoc Bonferroni testing was used for intergroup and intragroup comparisons (level of significance was set to 5%). Cohen d was used to calculate the effect size. In the intragroup analysis, significant increases in ROM were found for all measures in both the massage and occlusal splint groups (P massage therapy and asymptomatic comparison groups (0.2 Massage therapy on the masticatory muscles and the use of an occlusal splint lead to an increase in mandibular ROM similar to that of the asymptomatic comparison group with regard to maximum active mouth opening and both right and left excursion in individuals with TMD. © 2013. Published by National University of Health Sciences All rights reserved.

  18. Fuzzy control with random delays using invariant cones and its application to control of energy processes in microelectromechanical motion devices

    Energy Technology Data Exchange (ETDEWEB)

    Sinha, A.S.C. [Purdue Univ., Indianapolis, IN (United States). Dept. of Electrical Engineering; Lyshevski, S. [Rochester Inst. of Technology, NY (United States)

    2005-05-01

    In this paper, a class of microelectromechanical systems described by nonlinear differential equations with random delays is examined. Robust fuzzy controllers are designed to control the energy conversion processes with the ultimate objective to guarantee optimal achievable performance. The fuzzy rule base used consists of a collection of r fuzzy IF-THEN rules defined as a function of the conditional variable. The method of the theory of cones and Lyapunov functionals is used to design a class of local fuzzy control laws. A verifiably sufficient condition for stochastic stability of fuzzy stochastic microelectromechanical systems is given. As an example, we have considered the design of a fuzzy control law for an electrostatic micromotor. (author)

  19. Fuzzy control with random delays using invariant cones and its application to control of energy processes in microelectromechanical motion devices

    International Nuclear Information System (INIS)

    Sinha, A.S.C.; Lyshevski, S.

    2005-01-01

    In this paper, a class of microelectromechanical systems described by nonlinear differential equations with random delays is examined. Robust fuzzy controllers are designed to control the energy conversion processes with the ultimate objective to guarantee optimal achievable performance. The fuzzy rule base used consists of a collection of r fuzzy IF-THEN rules defined as a function of the conditional variable. The method of the theory of cones and Lyapunov functionals is used to design a class of local fuzzy control laws. A verifiably sufficient condition for stochastic stability of fuzzy stochastic microelectromechanical systems is given. As an example, we have considered the design of a fuzzy control law for an electrostatic micromotor

  20. Thermal behavior for a nanoscale two ferromagnetic phase system based on random anisotropy model

    International Nuclear Information System (INIS)

    Muraca, D.; Sanchez, F.H.; Pampillo, L.G.; Saccone, F.D.

    2010-01-01

    Advances in theory that explain the magnetic behavior as function of temperature for two phase nanocrystalline soft magnetic materials are presented. The theory developed is based on the well known random anisotropy model, which includes the crystalline exchange stiffness and anisotropy energies in both amorphous and crystalline phases. The phenomenological behavior of the coercivity was obtained in the temperature range between the amorphous phase Curie temperature and the crystalline phase one.

  1. Thermal OH Emission, A New Tracer for Galaxy Structure: Z-Thickness and Rolling Motion of the Perseus Arm

    Science.gov (United States)

    Engelke, Philip; Allen, Ronald J.; Hogg, David E.

    2016-06-01

    Recent observations with the Green Bank Telescope (Allen et al. 2015) have shown that high-sensitivity measurements of OH 18-cm emission can be a useful alternative tracer for the large-scale distribution of molecular gas in the Galactic ISM. This component of the ISM is not well traced by 3-mm CO(1-0) emission. In the quiescent regions examined so far, fewer than half of the OH spectral features found show corresponding CO emission in the CfA survey (Dame el al. 2001). The intensities of the two main-line OH transitions at 1665 and 1667 MHz are in the “thermal” or LTE ratio of 5:9 and emanate from low-opacity gas with a wide spatial distribution similar to the HI. This morphology resembles that of the “dark gas” (or “dark neutral medium”) postulated by Grenier et al. (2005) as the possible source of target nucleii required to explain the excess gamma ray emission from the Galactic ISM. OH 18-cm emission provides a new tool for studies of the quantity, distance, and kinematics of this new CO-dark molecular component of the ISM. As a demonstration of the utility of this new tool, we apply it to two questions about the molecular structure of the Perseus Arm: the thickness in the z-direction, and the rolling motions of the arm discovered in the earliest HI maps of the Galaxy (e.g. Oort 1962, Rougoor 1964). Using OH emission as a molecular tracer, we find that the molecular component of gas in the Perseus Arm has a comparable z-thickness to that measured using HI, although it appears to be clumpier. OH also shows that the molecular component experiences the “rolling motions” known from the HI data. As a molecular tracer, OH allows more regions to be observed than can be observed using CO(1-0), and as an optically-thin emission line, OH can provide direct column density measurements.

  2. Intra-articular morphine versus bupivacaine for knee motion among patients with osteoarthritis: randomized double-blind clinical trial

    Directory of Open Access Journals (Sweden)

    Miriam Bellini Gazi

    Full Text Available CONTEXT AND OBJECTIVE: Osteoarthritis causes pain and disability in a high percentage of elderly people. The aim of the present study was to assess the efficacy of intra-articular morphine and bupivacaine on the joint flexion and extension angles of patients with knee osteoarthritis. DESIGN AND SETTING: A randomized double-blind study was performed at a pain clinic of Universidade Federal de São Paulo. METHODS: Thirty-nine patients with pain for more than three months, of intensity greater than three on a numerical scale (zero to 10, were included. G1 patients received 1 mg (1 ml of morphine diluted in 9 ml of saline, intra-articularly, and G2 patients received 25 mg (10 ml of 0.25% bupivacaine without epinephrine. Pain was assessed on a numerical scale and knee flexion and extension angles were measured after administration of the drugs at rest and during movement. The total amount of analgesic supplementation using 500 mg doses of paracetamol was also determined. RESULTS: No significant difference in pain intensity was observed between G1 and G2. Significant decreases in pain at rest and during movement and significant increases in mean flexion and extension angles were observed in both groups, with no significant difference between the two groups. The mean total amount of paracetamol used over a seven-day period was 3578 mg in G1 and 5333 mg in G2 (P = 0.2355; Mann-Whitney test. CONCLUSION: The analgesic effects of 1 mg of morphine and 25 mg of 0.25% bupivacaine were similar among patients with osteoarthritis of the knee.

  3. Pain intensity and cervical range of motion in women with myofascial pain treated with acupuncture and electroacupuncture: a double-blinded, randomized clinical trial

    Science.gov (United States)

    Aranha, Maria F. M.; Müller, Cristina E. E.; Gavião, Maria B. D.

    2015-01-01

    BACKGROUND: Acupuncture stimulates points on the body, influencing the perception of myofascial pain or altering physiologic functions. OBJECTIVE: The aim was to evaluate the effect of electroacupuncture (EAC) and acupuncture (AC) for myofascial pain of the upper trapezius and cervical range of motion, using SHAM acupuncture as control. METHOD: Sixty women presenting at least one trigger point at the upper trapezius and local or referred pain for more than six months were randomized into EAC, AC, and SHAM groups. Eight sessions were scheduled and a follow-up was conducted after 28 days. The Visual Analog Scale assessed the intensity of local and general pain. A fleximeter assessed cervical movements. Data were analyzed using paired t or Wilcoxon's tests, ANOVA or Friedman or Kruskal-Wallis tests and Pearson's correlation (α=0.05). RESULTS: There was reduction in general pain in the EAC and AC groups after eight sessions (P<0.001). A significant decrease in pain intensity occurred for the right trapezius in all groups and for the left trapezius in the EAC and AC groups. Intergroup comparisons showed improvement in general pain in the EAC and AC groups and in local pain intensity in the EAC group (P<0.05), which showed an increase in left rotation (P=0.049). The AC group showed increases in inclination (P=0.005) sustained until follow-up and rotation to the right (P=0.032). CONCLUSION : EAC and AC were effective in reducing the pain intensity compared with SHAM. EAC was better than AC for local pain relief. These treatments can assist in increasing cervical range of motion, albeit subtly. PMID:25714602

  4. Integrated thermal infrared imaging and Structure-from-Motion photogrametry to map apparent temperature and radiant hydrothermal heat flux at Mammoth Mountain, CA USA

    Science.gov (United States)

    Lewis, Aaron; George Hilley,; Lewicki, Jennifer L.

    2015-01-01

    This work presents a method to create high-resolution (cm-scale) orthorectified and georeferenced maps of apparent surface temperature and radiant hydrothermal heat flux and estimate the radiant hydrothermal heat emission rate from a study area. A ground-based thermal infrared (TIR) camera was used to collect (1) a set of overlapping and offset visible imagery around the study area during the daytime and (2) time series of co-located visible and TIR imagery at one or more sites within the study area from pre-dawn to daytime. Daytime visible imagery was processed using the Structure-from-Motion photogrammetric method to create a digital elevation model onto which pre-dawn TIR imagery was orthorectified and georeferenced. Three-dimensional maps of apparent surface temperature and radiant hydrothermal heat flux were then visualized and analyzed from various computer platforms (e.g., Google Earth, ArcGIS). We demonstrate this method at the Mammoth Mountain fumarole area on Mammoth Mountain, CA. Time-averaged apparent surface temperatures and radiant hydrothermal heat fluxes were observed up to 73.7 oC and 450 W m-2, respectively, while the estimated radiant hydrothermal heat emission rate from the area was 1.54 kW. Results should provide a basis for monitoring potential volcanic unrest and mitigating hydrothermal heat-related hazards on the volcano.

  5. Optimization of incremental structure from motion combining a random k-d forest and pHash for unordered images in a complex scene

    Science.gov (United States)

    Zhan, Zongqian; Wang, Chendong; Wang, Xin; Liu, Yi

    2018-01-01

    On the basis of today's popular virtual reality and scientific visualization, three-dimensional (3-D) reconstruction is widely used in disaster relief, virtual shopping, reconstruction of cultural relics, etc. In the traditional incremental structure from motion (incremental SFM) method, the time cost of the matching is one of the main factors restricting the popularization of this method. To make the whole matching process more efficient, we propose a preprocessing method before the matching process: (1) we first construct a random k-d forest with the large-scale scale-invariant feature transform features in the images and combine this with the pHash method to obtain a value of relatedness, (2) we then construct a connected weighted graph based on the relatedness value, and (3) we finally obtain a planned sequence of adding images according to the principle of the minimum spanning tree. On this basis, we attempt to thin the minimum spanning tree to reduce the number of matchings and ensure that the images are well distributed. The experimental results show a great reduction in the number of matchings with enough object points, with only a small influence on the inner stability, which proves that this method can quickly and reliably improve the efficiency of the SFM method with unordered multiview images in complex scenes.

  6. Effects of therapeutic exercise and hydrotherapy on pain severity and knee range of motion in patients with hemophilia: a randomized controlled trial.

    Science.gov (United States)

    Mazloum, Vahid; Rahnama, Nader; Khayambashi, Khalil

    2014-01-01

    Pain and limited range of motion (ROM) are the crucial subsequent results of joint hemorrhages in individuals with bleeding disorders and hemophilia. Exercise interventions are particularly recommended in treatment of such patients. The purpose of this study was to detect the influences of conventional exercise therapy and hydrotherapy on the knee joint complications in patients with hemophilia. A total of 40 patients engaging hemophilia A were randomized into one of three groups: Therapeutic exercise (N = 13), hydrotherapy (N = 14) or control (N = 13). While the first two groups followed their specific programs for 4 weeks, routine life-style was maintained by subjects in the control group in this period. To evaluate the pain level and knee ROM the visual analog scale and standard goniometer were utilized, respectively. The outcome was measured at baseline and after completing the prescribed protocols. Data analysis was performed using one-way analysis of variance and Scheffe statistical tests (P hydrotherapy in comparison to exercise therapy, the difference in ROM improvement was not statistically significant (P > 0.05). Using hydrotherapy in addition to usual rehabilitation training can result in beneficial effect in terms of pain and knee joint ROM. However, it appears that hydrotherapy is more effective in reducing pain.

  7. Eliminating thermal violin spikes from LIGO noise

    Energy Technology Data Exchange (ETDEWEB)

    Santamore, D. H.; Levin, Yuri

    2001-08-15

    We have developed a scheme for reducing LIGO suspension thermal noise close to violin-mode resonances. The idea is to monitor directly the thermally induced motion of a small portion of (a 'point' on) each suspension fiber, thereby recording the random forces driving the test-mass motion close to each violin-mode frequency. One can then suppress the thermal noise by optimally subtracting the recorded fiber motions from the measured motion of the test mass, i.e., from the LIGO output. The proposed method is a modification of an analogous but more technically difficult scheme by Braginsky, Levin and Vyatchanin for reducing broad-band suspension thermal noise. The efficiency of our method is limited by the sensitivity of the sensor used to monitor the fiber motion. If the sensor has no intrinsic noise (i.e. has unlimited sensitivity), then our method allows, in principle, a complete removal of violin spikes from the thermal-noise spectrum. We find that in LIGO-II interferometers, in order to suppress violin spikes below the shot-noise level, the intrinsic noise of the sensor must be less than {approx}2 x 10{sup -13} cm/Hz. This sensitivity is two orders of magnitude greater than that of currently available sensors.

  8. Eliminating thermal violin spikes from LIGO noise

    International Nuclear Information System (INIS)

    Santamore, D. H.; Levin, Yuri

    2001-01-01

    We have developed a scheme for reducing LIGO suspension thermal noise close to violin-mode resonances. The idea is to monitor directly the thermally induced motion of a small portion of (a 'point' on) each suspension fiber, thereby recording the random forces driving the test-mass motion close to each violin-mode frequency. One can then suppress the thermal noise by optimally subtracting the recorded fiber motions from the measured motion of the test mass, i.e., from the LIGO output. The proposed method is a modification of an analogous but more technically difficult scheme by Braginsky, Levin and Vyatchanin for reducing broad-band suspension thermal noise. The efficiency of our method is limited by the sensitivity of the sensor used to monitor the fiber motion. If the sensor has no intrinsic noise (i.e. has unlimited sensitivity), then our method allows, in principle, a complete removal of violin spikes from the thermal-noise spectrum. We find that in LIGO-II interferometers, in order to suppress violin spikes below the shot-noise level, the intrinsic noise of the sensor must be less than ∼2 x 10 -13 cm/Hz. This sensitivity is two orders of magnitude greater than that of currently available sensors

  9. [Study of blood sedimentation by photo-thermal radiometry with random excitation].

    Science.gov (United States)

    Antoniow, J S; Marx, J; Egee, M; Droulle, C; Potron, G

    1994-01-01

    The erythrocyte sedimentation rate is a complex phenomena involving a large number of parameters. The rate of sedimentation is highly dependent on the haematocrit, the internal viscosity of the red cells and the viscosity of the suspending medium and its composition. The experimental conditions also have a non-negligible effect (geometry and nature of the test tube, temperature, foreign substances in the medium...). In order to respond to the need for more precise and more rapid methods of analyzing the erythrocyte sedimentation rate, we developed new physical methods allowing a real time evaluation of the phenomena involved. Several of these new photothermal methods have already been applied for non-destructive evaluation of thin or layered material (such as composite material or glued structures) both in laboratory situations and in the industry. When a material is placed in a modulated laser beam, the incident rays absorbed heat the sample. The heat then diffuses throughout the material and the surface temperature of the sample increases locally with a periodicity. The surface thus emits a modulated flow of infrared radiation. The amplitude and phase shift of the photothermal signal generated is characteristically dependent of the optic and thermal properties of the material for a given modulation frequency. The early photothermal modelling based on a two-layer model and a physico-mathematical theory of red cell sedimentation proposed by S. Oka made it possible to simulate the phenomena as they occur over time. We hypothesize that the temperature gradients created within the sample are too small to create a convection current and that the all heat transfer occurs by conduction.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. Planar random motions with drift

    Directory of Open Access Journals (Sweden)

    E. Orsingher

    2002-01-01

    different speeds, switching at Poisson paced times. We are able to obtain, in some cases, the explicit distribution of the position (X(t,Y(t, t>0 in all its components (the discrete one, lying on the edge ∂Qt of the probability support Qt, as well as the absolutely continuous one, concentrated inside Qt.

  11. The immediate effects of two manual therapy techniques on ankle musculoarticular stiffness and dorsiflexion range of motion in people with chronic ankle rigidity: A randomized clinical trial.

    Science.gov (United States)

    Hidalgo, Benjamin; Hall, Toby; Berwart, Mathilde; Biernaux, Elinor; Detrembleur, Christine

    2017-12-29

    Ankle rigidity is a common musculoskeletal disorder affecting the talocrural joint, which can impair weight-bearing ankle dorsiflexion (WBADF) and daily-life in people with or without history of ankle injuries. Our objective was to compare the immediate effects of efficacy of Mulligan Mobilization with Movement (MWM) and Osteopathic Mobilization (OM) for improving ankle dorsiflexion range of motion (ROM) and musculoarticular stiffness (MAS) in people with chronic ankle dorsiflexion rigidity. A randomized clinical trial with two arms. Patients were recruited by word of mouth and via social network as well as posters, and analyzed in the neuro musculoskeletal laboratory of the "Université Catholique de Louvain-la-Neuve", Brussels, Belgium. 67 men (aged 18-40 years) presenting with potential chronic non-specific and unilateral ankle mobility deficit during WBDF were assessed for eligibility and finally 40 men were included and randomly allocated to single session of either MWM or OM. Two modalities of manual therapy indicated for hypothetic immediate effects in chronic ankle dorsiflexion stiffness, i.e. MWM and OM, were applied during a single session on included patients. Comprised blinding measures of MAS with a specific electromechanical device (namely: Lehmann's device) producing passive oscillatory ankle joint dorsiflexion and with clinical measures of WBADF-ROM as well. A two-way ANOVA revealed a non-significant interaction between both techniques and time for all outcome measures. For measures of MAS: elastic-stiffness (p= 0.37), viscous-stiffness (p= 0.83), total-stiffness (p= 0.58). For WBADF-ROM: toe-wall distance (p= 0.58) and angular ROM (p= 0.68). Small effect sizes between groups were determined with Cohen's d ranging from 0.05 to 0.29. One-way ANOVA demonstrated non-significant difference and small to moderate effects sizes (d= 0.003-0.58) on all outcome measures before and after interventions within both groups. A second two-way ANOVA analyzed the

  12. Visual Motion Perception

    Science.gov (United States)

    1991-08-15

    displace- ment limit for motion in random dots," Vision Res., 24, 293-300. Pantie , A. & K. Turano (1986) "Direct comparisons of apparent motions...Hicks & AJ, Pantie (1978) "Apparent movement of successively generated subjec. uve figures," Perception, 7, 371-383. Ramachandran. V.S. & S.M. Anstis...thanks think deaf girl until world uncle flag home talk finish short thee our screwdiver sonry flower wrCstlir~g plan week wait accident guilty tree

  13. Continuous passive motion and physical therapy (CPM) versus physical therapy (PT) versus delayed physical therapy (DPT) after surgical release for elbow contractures; a study protocol for a prospective randomized controlled trial.

    Science.gov (United States)

    Viveen, Jetske; Doornberg, Job N; Kodde, Izaak F; Goossens, Pjotr; Koenraadt, Koen L M; The, Bertram; Eygendaal, Denise

    2017-11-22

    The elbow is prone to stiffness after trauma. To regain functional elbow motion several conservative- and surgical treatment options are available. Conservative treatment includes physical therapy, intra-articular injections with corticosteroids and a static progressive or dynamic splinting program. If conservative treatment fails, an operative release of the posttraumatic stiff elbow is often performed. The best Evidence-Based rehabilitation protocol for patients after an operative release is unknown to date and differs per surgeon, hospital and country. Options include early- or delayed motion supervised by a physical therapist, immediate continuous passive motion (CPM), (night) splinting and a static progressive or dynamic splinting program. The SET-Study (Stiff Elbow Trial) is a single-centre, prospective, randomized controlled trial. The primary objective of this study is to compare the active Range of Motion (ROM) (flexion arc and rotational arc) twelve months after surgery between three groups. The first group will receive in-hospital CPM in combination with early motion Physical Therapy (PT) supervised by a physical therapist, the second group will receive only in-hospital early motion PT supervised by a physical therapist and the third group will receive outpatient supervised PT from postoperative day seven till ten. Secondary outcome measures will be Patient Reported Outcome Measures (PROMs) including the Mayo Elbow Performance Score (MEPS), the Oxford Elbow Score (OES), the quick Disabilities of Arm, Shoulder and Hand (qDASH) score, Visual Analogue pain Scale in rest and activity (VAS), Pain Catastrophizing Scale (PCS), the Short Form (SF)-36, the Centre for Epidemiological Studies Depression Scale Revised (CESD-R) and the Work Rehabilitation Questionnaire (WORQ) for the upper limb. A successful completion of this trial will provide evidence on the best rehabilitation protocol in order to (re)gain optimal motion after surgical release of the stiff elbow

  14. Short-term changes in neck pain, widespread pressure pain sensitivity, and cervical range of motion after the application of trigger point dry needling in patients with acute mechanical neck pain: a randomized clinical trial.

    Science.gov (United States)

    Mejuto-Vázquez, María J; Salom-Moreno, Jaime; Ortega-Santiago, Ricardo; Truyols-Domínguez, Sebastián; Fernández-de-Las-Peñas, César

    2014-04-01

    Randomized clinical trial. To determine the effects of trigger point dry needling (TrPDN) on neck pain, widespread pressure pain sensitivity, and cervical range of motion in patients with acute mechanical neck pain and active trigger points in the upper trapezius muscle. TrPDN seems to be effective for decreasing pain in individuals with upper-quadrant pain syndromes. Potential effects of TrPDN for decreasing pain and sensitization in individuals with acute mechanical neck pain are needed. Methods Seventeen patients (53% female) were randomly assigned to 1 of 2 groups: a single session of TrPDN or no intervention (waiting list). Pressure pain thresholds over the C5-6 zygapophyseal joint, second metacarpal, and tibialis anterior muscle; neck pain intensity; and cervical spine range-of-motion data were collected at baseline (pretreatment) and 10 minutes and 1 week after the intervention by an assessor blinded to the treatment allocation of the patient. Mixed-model analyses of variance were used to examine the effects of treatment on each outcome variable. Patients treated with 1 session of TrPDN experienced greater decreases in neck pain, greater increases in pressure pain threshold, and higher increases in cervical range of motion than those who did not receive an intervention at both 10 minutes and 1 week after the intervention (Ppain intensity and widespread pressure pain sensitivity, and also increase active cervical range of motion, in patients with acute mechanical neck pain. Changes in pain, pressure pain threshold, and cervical range of motion surpassed their respective minimal detectable change values, supporting clinically relevant treatment effects. Level of Evidence Therapy, level 1b-.

  15. Evaluation of the immediate effect of acupuncture on pain, cervical range of motion and electromyographic activity of the upper trapezius muscle in patients with nonspecific neck pain: study protocol for a randomized controlled trial.

    Science.gov (United States)

    Calamita, Simone Aparecida Penimpedo; Biasotto-Gonzalez, Daniela Aparecida; De Melo, Nivea Cristina; dos Santos, Douglas Meira; de Lassa, Roberta; de Mendonça, Fabiana Sarilho; Oliveira, Claudia Santos; Amorim, César Ferreira; Gonzalez, Tabajara Oliveira; Fumagalli, Marco Antônio; de Gomes, Cid André Fidelis Paula; Politti, Fabiano

    2015-03-19

    Nonspecific neck pain can cause considerable suffering, possible disability and reductions in quality of life and productivity. The aim of the proposed study is to evaluate the immediate effect of acupuncture on pain, cervical range of motion and electromyographic activity of the upper trapezius muscle in patients with nonspecific neck pain. A total of 12 patients with nonspecific neck pain and 12 healthy subjects will be enrolled in a randomized, single-blind crossover study. Each subject will receive two forms of treatment in random order: a single session of traditional acupuncture (acupoints: triple energizer 5, 'Wai-guan' and large intestine 11, 'Qu-chi') and sham acupuncture. To eliminate carry-over treatment effects, a one-week wash-out period will be respected between sessions. Surface electromyography will be used to determine motor control in the upper trapezius muscle before and after treatment. The outcome measures in the group with neck pain will be a numerical pain rating scale (range: 0 (no pain) to 10 (maximum pain)), documentation of the pain area on a body chart and cervical range of motion. Comparisons before and after acupuncture treatment will demonstrate whether acupoints affect the activity of the upper trapezius muscle, pain and cervical range of motion. The purpose of this randomized clinical trial is to evaluate the immediate effect of acupuncture on pain, cervical range of motion and electromyographic activity of the upper trapezius muscle in patients with nonspecific neck pain. Data will be published after the study is completed. The study will support the practice of evidence-based physical therapy for individuals with nonspecific neck pain. This trial was registered with Clinicaltrials.gov (identifier: NCT0984021 ) on 7 November 2013 ( https://clinicaltrials.gov/ct2/show/NCT01984021 ).

  16. Comparing the Effects of Therapeutic Exercise and Hydrotherapy on Pain Severity and Knee Range of Motion in Patients with Hemophilia: A Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    V Mazloum

    2013-10-01

    . Results: Both experimental groups exhibited significant reduction of pain along with improved knee flexion and extension compared with the control group (P<0.001. Pain reduction in subjects treated in water treatment was significantly higher than exercise group in drought (P0.05. Conclusion: The use of therapeutic exercise in water with regular exercise rehabilitation for patients with hemophilia can be helpful to reduce pain and improve range of motion in hemophilia patients. The effect of exercise therapy on pain reduction is more effective compared to traditional pain therapy. Key words: Hydrotherapy, Exercise Therapy, Hemophilia, Knee Range of Motion

  17. Universal short-time motion of a polymer in a random environment: Analytical calculations, a blob picture, and Monte Carlo results

    NARCIS (Netherlands)

    Ebert, U.; Baumgärtner, A.; Schäfer, L.

    1996-01-01

    Using a recently established renormalization group approach [U. Ebert, J. Stat. Phys. (to be published)], we analyze the center-of-mass motion of a polymer in a Gaussian disordered potential. While in the long-time limit normal diffusion is found, we concentrate here on shorter times. We discuss the

  18. Survey of strong motion earthquake effects on thermal power plants in California with emphasis on piping systems. Volume 1, Main report

    International Nuclear Information System (INIS)

    Stevenson, J.D.

    1995-11-01

    Since 1982, there has been a major effort expended to evaluate the susceptibility of nuclear Power plant equipment to failure and significant damage during seismic events. This was done by making use of data on the performance of electrical and mechanical equipment in conventional power plants and other similar industrial facilities during strong motion earthquakes. This report is intended as an extension of the seismic experience data collection effort and a compilation of experience data specific to power plant piping and supports designed and constructed US power piping code requirements which have experienced strong motion earthquakes. Eight damaging (Richter Magnitude 7.7 to 5.5) California earthquakes and their effects on 8 power generating facilities in use natural gas and California were reviewed. All of these facilities were visited and evaluated. Seven fossel-fueled (dual use natural gas and oil) and one nuclear fueled plants consisting of a total of 36 individual boiler or reactor units were investigated. Peak horizontal ground accelerations that either had been recorded on site at these facilities or were considered applicable to these power plants on the basis of nearby recordings ranged between 0.20g and 0.5lg with strong motion durations which varied from 3.5 to 15 seconds. Most US nuclear power plants are designed for a safe shutdown earthquake peak ground acceleration equal to 0.20g or less with strong motion durations which vary from 10 to 15 seconds

  19. Effects of thermal and particle-number fluctuations on the giant isovector dipole modes for the 58Ni nucleus in the finite-temperature random-phase approximation

    International Nuclear Information System (INIS)

    Nguyen Dinhdang; Nguyen Zuythang

    1988-01-01

    Using the realistic single-particle energy spectrum obtained in the Woods-Saxon nucleon mean-field potential, we calculate the BCS pairing gap for 58 Ni as a function of temperature taking into account the thermal and particle-number fluctuations. The strength distributions of the electric dipole transitions and the centroids of the isovector giant dipole resonance (IV-GDR) are computed in the framework of the finite-temperature random-phase approximation (RPA) based on the Hamiltonian of the quasiparticle-phonon nuclear model with separate dipole forces. It is shown that the change of the pairing gap at finite temperature can noticeably influence the IV-GDR localisation in realistic nuclei. By taking both thermal and quasiparticle fluctuations in the pairing gap into account the effect of the phase transition from superfluid to normal in the temperature dependence of the IV-GDR centroid is completely smeared out. (author)

  20. A new thermal conductivity model for nanofluids

    Energy Technology Data Exchange (ETDEWEB)

    Koo, Junemoo; Kleinstreuer, Clement [Department of Mechanical and Aerospace Engineering (United States)], E-mail: ck@eos.ncsu.edu

    2004-12-15

    In a quiescent suspension, nanoparticles move randomly and thereby carry relatively large volumes of surrounding liquid with them. This micro-scale interaction may occur between hot and cold regions, resulting in a lower local temperature gradient for a given heat flux compared with the pure liquid case. Thus, as a result of Brownian motion, the effective thermal conductivity, k{sub eff}, which is composed of the particles' conventional static part and the Brownian motion part, increases to result in a lower temperature gradient for a given heat flux. To capture these transport phenomena, a new thermal conductivity model for nanofluids has been developed, which takes the effects of particle size, particle volume fraction and temperature dependence as well as properties of base liquid and particle phase into consideration by considering surrounding liquid traveling with randomly moving nanoparticles.The strong dependence of the effective thermal conductivity on temperature and material properties of both particle and carrier fluid was attributed to the long impact range of the interparticle potential, which influences the particle motion. In the new model, the impact of Brownian motion is more effective at higher temperatures, as also observed experimentally. Specifically, the new model was tested with simple thermal conduction cases, and demonstrated that for a given heat flux, the temperature gradient changes significantly due to a variable thermal conductivity which mainly depends on particle volume fraction, particle size, particle material and temperature. To improve the accuracy and versatility of the k{sub eff}model, more experimental data sets are needed.

  1. Optimizing phonon scattering by tuning surface-interdiffusion-driven intermixing to break the random-alloy limit of thermal conductivity

    Science.gov (United States)

    Yang, Xiaolong; Li, Wu

    2018-01-01

    We investigate the evolution of the cross-plane thermal conductivity κ of superlattices (SLs) as interfaces change from perfectly abrupt to totally intermixed, by using nonequilibrium molecular dynamics simulations in combination with the spectral heat current calculations. We highlight the role of surface-interdiffusion-driven intermixing by calculating the κ of SLs with changing interface roughness, whose tuning allows for κ values much lower than the "alloy limit" and the abrupt interface limit in same cases. The interplay between alloy and interface scattering in different frequency ranges provides a physical basis to predict a minimum of thermal conductivity. More specifically, we also explore how the interface roughness affects the thermal conductivities for SL materials with a broad span of atomic mass and bond strength. In particular, we find that (i) only when the "spacer" thickness of SLs increases up to a critical value, κ of rough SLs can break the corresponding "alloy limit," since SLs with different "spacer" thickness have different characteristic length of phonon transport, which is influenced by surface-interdiffusion-driven intermixing to different extend. (ii) Whether κ changes monotonically with interface roughness strongly depends on the period length and intrinsic behavior of phonon transport for SL materials. Especially, for the SL with large period length, there exists an optimal interface roughness that can minimize the thermal conductivity. (iii) Surface-interdiffusion-driven intermixing is more effective in achieving a low κ below the alloy limit for SL materials with large mass mismatch than with small one. (iv) It is possible for SL materials with large lattice mismatch (i.e., bond strength) to design an ideally abrupt interface structure with κ much below the alloy limit. These results have clear implications for optimization of thermal transport for heat management and for the development of thermoelectric materials.

  2. Simulated earthquake ground motions

    International Nuclear Information System (INIS)

    Vanmarcke, E.H.; Gasparini, D.A.

    1977-01-01

    The paper reviews current methods for generating synthetic earthquake ground motions. Emphasis is on the special requirements demanded of procedures to generate motions for use in nuclear power plant seismic response analysis. Specifically, very close agreement is usually sought between the response spectra of the simulated motions and prescribed, smooth design response spectra. The features and capabilities of the computer program SIMQKE, which has been widely used in power plant seismic work are described. Problems and pitfalls associated with the use of synthetic ground motions in seismic safety assessment are also pointed out. The limitations and paucity of recorded accelerograms together with the widespread use of time-history dynamic analysis for obtaining structural and secondary systems' response have motivated the development of earthquake simulation capabilities. A common model for synthesizing earthquakes is that of superposing sinusoidal components with random phase angles. The input parameters for such a model are, then, the amplitudes and phase angles of the contributing sinusoids as well as the characteristics of the variation of motion intensity with time, especially the duration of the motion. The amplitudes are determined from estimates of the Fourier spectrum or the spectral density function of the ground motion. These amplitudes may be assumed to be varying in time or constant for the duration of the earthquake. In the nuclear industry, the common procedure is to specify a set of smooth response spectra for use in aseismic design. This development and the need for time histories have generated much practical interest in synthesizing earthquakes whose response spectra 'match', or are compatible with a set of specified smooth response spectra

  3. Continuum Regime Motion of a Growing Droplet in Opposing Thermo-Diffusiophoretic and Gravitational Fields of a Thermal Diffusion Cloud Chamber

    Czech Academy of Sciences Publication Activity Database

    Bakanov, S. P.; Smolík, Jiří; Zaripov, S. K.; Ždímal, Vladimír

    2001-01-01

    Roč. 32, č. 3 (2001), s. 341-350 ISSN 0021-8502 R&D Projects: GA ČR GA104/97/1198 Grant - others:RFBR(RU) 99-01-00-169 Institutional research plan: CEZ:AV0Z4072921 Keywords : thermal diffusion cloud chamber * droplet growth * continuum regime Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.605, year: 2001

  4. Thermal-hydraulic study of fixed bed nuclear reactor (FBNR), in FCC, BCC and pseudo-random configurations of the core through CFD method

    International Nuclear Information System (INIS)

    Luna, M.; Chavez, I.; Cajas, D.; Santos, R.

    2015-01-01

    The study of thermal-hydraulic performance of a fixed bed nuclear reactor (FBNR) core and the effect of the porosity was studied by the CFD method with 'SolidWorks' software. The representative sections of three different packed beds arrangements were analyzed: face-centered cubic (FCC), body-centered cubic (BCC), and a pseudo-random, with values of porosity of 0.28, 0.33 and 0.53 respectively. The minimum coolant flow required to avoid the phase change for each one of the configurations was determined. The results show that the heat transfer rate increases when the porosity value decreases, and consequently the minimum coolant flow in each configuration. The results of minimum coolant flow were: 728.51 kg/s for the FCC structure, 372.72 kg/s for the BCC, and 304.96 kg/s for the pseudo-random. Meanwhile, the heat transfer coefficients in each packed bed were 6480 W/m 2 *K, 3718 W/m 2 *K and 3042 W/m 2 *K respectively. Finally the pressure drop was calculated, and the results were 0.588 MPa for FCC configuration, 0.033 MPa for BCC and 0.017 MPa for the pseudo-random one. This means that with a higher porosity, the fluid can circulate easier because there are fewer obstacles to cross, so there are fewer energy losses. (authors)

  5. Use of low level of continuous heat and Ibuprofen as an adjunct to physical therapy improves pain relief, range of motion and the compliance for home exercise in patients with nonspecific neck pain: A randomized controlled trial.

    Science.gov (United States)

    Petrofsky, Jerrold S; Laymon, Michael; Alshammari, Faris; Khowailed, Iman Akef; Lee, Haneul

    2017-01-01

    It has been well documented at heat reduces pain and increases healing by increasing blood flow in tissue. The purpose of this study was to see if the use of low level continuous heat (LLCH) and Ibuprofen used as a home therapy between physical therapy sessions at a clinic resulted in better therapy outcomes in people with chronic neck pain. Ninety-two patients with chronic nonspecific neck pain were randomly divided into 4 groups; LLCH group, LLCH with Ibuprofen (IP) group, sham LLCH with sham IP group, and controls. All subjects underwent 45 minutes of conventional physical therapy twice a week for 2 weeks. the neck disability index (NDI), subjective pain, range of motion (ROM), strength of the neck, and home exercise compliance were measured. Both LLCH and IP significantly reduced pain and NDI score, and increased ROM (ppain significantly improved pain attenuation and it causes greater compliance for home.

  6. Spatial filtering precedes motion detection.

    Science.gov (United States)

    Morgan, M J

    1992-01-23

    When we perceive motion on a television or cinema screen, there must be some process that allows us to track moving objects over time: if not, the result would be a conflicting mass of motion signals in all directions. A possible mechanism, suggested by studies of motion displacement in spatially random patterns, is that low-level motion detectors have a limited spatial range, which ensures that they tend to be stimulated over time by the same object. This model predicts that the direction of displacement of random patterns cannot be detected reliably above a critical absolute displacement value (Dmax) that is independent of the size or density of elements in the display. It has been inferred that Dmax is a measure of the size of motion detectors in the visual pathway. Other studies, however, have shown that Dmax increases with element size, in which case the most likely interpretation is that Dmax depends on the probability of false matches between pattern elements following a displacement. These conflicting accounts are reconciled here by showing that Dmax is indeed determined by the spacing between the elements in the pattern, but only after fine detail has been removed by a physiological prefiltering stage: the filter required to explain the data has a similar size to the receptive field of neurons in the primate magnocellular pathway. The model explains why Dmax can be increased by removing high spatial frequencies from random patterns, and simplifies our view of early motion detection.

  7. Caffeine ingestion changes time-motion and technical-tactical aspects in simulated boxing matches: A randomized double-blind PLA-controlled crossover study.

    Science.gov (United States)

    Coswig, Victor Silveira; Gentil, Paulo; Irigon, Francine; Del Vecchio, Fabrício Boscolo

    2018-05-08

    The number of offensive actions and glycolytic energy in combat sports both increase with caffeine (CAF) ingestion. In addition, the effects of CAF on technical-tactical and time-motion analysis and physiological parameters in boxing are unknown. This study aimed to investigate the effects of CAF ingestion on physiological parameters and the notational analysis of boxing matches. Ten male boxers were recruited; the participants ingested 6 mg kg -1 BM of CAF or placebo (PLA) 30 min prior to the match in a crossover design. Heart rate (HR) and rate of perceived exertion (RPE) were collected before and after each of three 2 min rounds, interspersed by 1-min recovery; the matches were recorded for notational analysis. A two-way ANOVA for repeated measures was used for the physiological variables, and a three-way ANOVA with repeated measures was used for technical-tactical and time-motion variables. Statistical differences were found for HR and RPE between rounds (F (6, 54)  = 131.3, p = .001; [Formula: see text] = 0.93 and F (2, 18)  = 40.6, p = .001; [Formula: see text] = 0.81, respectively) but not between conditions (F (1, 9)  = 0.46; p = .51; [Formula: see text] = 0.05 and F (1, 9)  = 0.02, p = .89; [Formula: see text] = 0.002, respectively). The CAF condition induced a greater duration of interaction blocks (CAF = 6.5 ± 1.8 s; PLA = 4.4 ± 0.9 s; p = .01). Effort:pause ratio was 4.4 s:8.7 s (approx. 1:2) for PLA and 6.5 s:9.4 s (1:1.44) for CAF, which were significantly different (p boxing matches induces a greater duration of high-intensity actions, with no effects on internal load markers.

  8. Perioperative warming with a thermal gown prevents maternal temperature loss during elective cesarean section. A randomized clinical trial.

    Science.gov (United States)

    de Bernardis, Ricardo Caio Gracco; Siaulys, Monica Maria; Vieira, Joaquim Edson; Mathias, Lígia Andrade Silva Telles

    2016-01-01

    Decrease in body temperature is common during general and regional anesthesia. Forced-air warming intraoperative during cesarean section under spinal anesthesia seems not able to prevent it. The hypothesis considers that active warming before the intraoperative period avoids temperature loss during cesarean. Forty healthy pregnant patients undergoing elective cesarean section with spinal anesthesia received active warming from a thermal gown in the preoperative care unit 30min before spinal anesthesia and during surgery (Go, n=20), or no active warming at any time (Ct, n=20). After induction of spinal anesthesia, the thermal gown was replaced over the chest and upper limbs and maintained throughout study. Room temperature, hemoglobin saturation, heart rate, arterial pressure, and tympanic body temperature were registered 30min before (baseline) spinal anesthesia, right after it (time zero) and every 15min thereafter. There was no difference for temperature at baseline, but they were significant throughout the study (p<0.0001; repeated measure ANCOVA). Tympanic temperature baseline was 36.6±0.3°C, measured 36.5±0.3°C at time zero and reached 36.1±0.2°C for gown group, while control group had baseline temperature of 36.4±0.4°C, measured 36.3±0.3°C at time zero and reached 35.4±0.4°C (F=32.53; 95% CI 0.45-0.86; p<0.001). Hemodynamics did not differ throughout the study for both groups of patients. Active warming 30min before spinal anesthesia and during surgery prevented a fall in body temperature in full-term pregnant women during elective cesarean delivery. Copyright © 2015 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

  9. [Perioperative warming with a thermal gown prevents maternal temperature loss during elective cesarean section. A randomized clinical trial].

    Science.gov (United States)

    Bernardis, Ricardo Caio Gracco de; Siaulys, Monica Maria; Vieira, Joaquim Edson; Mathias, Lígia Andrade Silva Telles

    2016-01-01

    Decrease in body temperature is common during general and regional anesthesia. Forced-air warming intraoperative during cesarean section under spinal anesthesia seems not able to prevent it. The hypothesis considers that active warming before the intraoperative period avoids temperature loss during cesarean. Forty healthy pregnant patients undergoing elective cesarean section with spinal anesthesia received active warming from a thermal gown in the preoperative care unit 30min before spinal anesthesia and during surgery (Go, n=20), or no active warming at any time (Ct, n=20). After induction of spinal anesthesia, the thermal gown was replaced over the chest and upper limbs and maintained throughout study. Room temperature, hemoglobin saturation, heart rate, arterial pressure, and tympanic body temperature were registered 30min before (baseline) spinal anesthesia, right after it (time zero) and every 15min thereafter. There was no difference for temperature at baseline, but they were significant throughout the study (p<0.0001; repeated measure ANCOVA). Tympanic temperature baseline was 36.6±0.3°C, measured 36.5±0.3°C at time zero and reached 36.1±0.2°C for gown group, while control group had baseline temperature of 36.4±0.4°C, measured 36.3±0.3°C at time zero and reached 35.4±0.4°C (F=32.53; 95% CI 0.45-0.86; p<0.001). Hemodynamics did not differ throughout the study for both groups of patients. Active warming 30min before spinal anesthesia and during surgery prevented a fall in body temperature in full-term pregnant women during elective cesarean delivery. Copyright © 2015 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

  10. Thermal discomfort with cold extremities in relation to age, gender, and body mass index in a random sample of a Swiss urban population

    Directory of Open Access Journals (Sweden)

    Orgül Selim

    2010-06-01

    Full Text Available Abstract Background The aim of this epidemiological study was to investigate the relationship of thermal discomfort with cold extremities (TDCE to age, gender, and body mass index (BMI in a Swiss urban population. Methods In a random population sample of Basel city, 2,800 subjects aged 20-40 years were asked to complete a questionnaire evaluating the extent of cold extremities. Values of cold extremities were based on questionnaire-derived scores. The correlation of age, gender, and BMI to TDCE was analyzed using multiple regression analysis. Results A total of 1,001 women (72.3% response rate and 809 men (60% response rate returned a completed questionnaire. Statistical analyses revealed the following findings: Younger subjects suffered more intensely from cold extremities than the elderly, and women suffered more than men (particularly younger women. Slimmer subjects suffered significantly more often from cold extremities than subjects with higher BMIs. Conclusions Thermal discomfort with cold extremities (a relevant symptom of primary vascular dysregulation occurs at highest intensity in younger, slimmer women and at lowest intensity in elderly, stouter men.

  11. Influence of Thermal Annealing Treatment on Bipolar Switching Properties of Vanadium Oxide Thin-Film Resistance Random-Access Memory Devices

    Science.gov (United States)

    Chen, Kai-Huang; Cheng, Chien-Min; Kao, Ming-Cheng; Chang, Kuan-Chang; Chang, Ting-Chang; Tsai, Tsung-Ming; Wu, Sean; Su, Feng-Yi

    2017-04-01

    The bipolar switching properties and electrical conduction mechanism of vanadium oxide thin-film resistive random-access memory (RRAM) devices obtained using a rapid thermal annealing (RTA) process have been investigated in high-resistive status/low-resistive status (HRS/LRS) and are discussed herein. In addition, the resistance switching properties and quality improvement of the vanadium oxide thin-film RRAM devices were measured by x-ray diffraction (XRD) analysis, x-ray photoelectron spectrometry (XPS), scanning electron microscopy (SEM), atomic force microscopy (AFM), and current-voltage ( I- V) measurements. The activation energy of the hopping conduction mechanism in the devices was investigated based on Arrhenius plots in HRS and LRS. The hopping conduction distance and activation energy barrier were obtained as 12 nm and 45 meV, respectively. The thermal annealing process is recognized as a candidate method for fabrication of thin-film RRAM devices, being compatible with integrated circuit technology for nonvolatile memory devices.

  12. Thermal quantitative sensory testing to assess the sensory effects of three local anesthetic solutions in a randomized trial of interscalene blockade for shoulder surgery.

    Science.gov (United States)

    Sermeus, Luc A; Hans, Guy H; Schepens, Tom; Bosserez, Nathalie M-L; Breebaart, Margaretha B; Smitz, Carine J; Vercauteren, Marcel P

    2016-01-01

    This study investigated whether quantitative sensory testing (QST) with thermal stimulations can quantitatively measure the characteristics of an ultrasound-guided interscalene brachial plexus block (US-ISB). This was a prospective randomized trial in patients scheduled for arthroscopic shoulder surgery under general anesthesia and US-ISB. Participants and observers were blinded for the study. We assigned the study participants to one of three groups: 0.5% levobupivacaine 15 mL, 0.5% levobupivacaine 15 mL with 1:200,000 epinephrine, and 0.75% ropivacaine 15 mL. We performed thermal QST within dermatomes C4, C5, C6, and C7 before infiltration and 30 min, six hours, ten hours, and 24 hr after performing the US-ISB. In addition, we used QST, a semi-objective quantitative testing method, to measure the onset, intensity, duration, extent, and functional recovery of the sensory block. We also measured detection thresholds for cold/warm sensations and cold/heat pain. Detection thresholds for all thermal sensations within the ipsilateral C4, C5, C6, and C7 dermatomes increased rapidly (indicating the development of a hypoesthetic state) and reached a steady state after 30 min. This lasted for approximately ten hours and returned to normal detection thresholds by 24 hr. There were no differences detected between the three groups at 24 hr when we compared warm sensation thresholds on one dermatome. Visual inspection of the pooled results per dermatome suggests the ability of QST to detect clinically relevant differences in block intensity per dermatome. Quantitative sensory testing can be useful as a method for detecting the presence and characteristics of regional anesthesia-induced sensory block and may be used for the evaluation of clinical protocols. The three local anesthetic solutions exhibited a similar anesthetic effect. The results support the use of QST to assess block characteristics quantitatively under clinical research conditions. This trial was registered at

  13. Origins of ion irradiation-induced Ga nanoparticle motion on GaAs surfaces

    International Nuclear Information System (INIS)

    Kang, M.; Wu, J. H.; Chen, H. Y.; Thornton, K.; Goldman, R. S.; Sofferman, D. L.; Beskin, I.

    2013-01-01

    We have examined the origins of ion irradiation-induced nanoparticle (NP) motion. Focused-ion-beam irradiation of GaAs surfaces induces random walks of Ga NPs, which are biased in the direction opposite to that of ion beam scanning. Although the instantaneous NP velocities are constant, the NP drift velocities are dependent on the off-normal irradiation angle, likely due to a difference in surface non-stoichiometry induced by the irradiation angle dependence of the sputtering yield. It is hypothesized that the random walks are initiated by ion irradiation-induced thermal fluctuations, with biasing driven by anisotropic mass transport

  14. Correlation of photon beam motion with vacuum chamber cooling on the NSLS x-ray ring

    International Nuclear Information System (INIS)

    Johnson, E.D.; Fauchet, A.M.; Zhang, Xiaohao.

    1991-01-01

    The NSLS X-ray ring exhibits a direct correlation between photon beam motion, and distortion of the ring vacuum chamber induced by fluctuations in the cooling system. We have made long term measurements of photon beam vertical position, accelerator vacuum chamber motion, process water temperatures, and angular motions of the magnets around one superperiod of the NSLS x-ray ring. Short term transients in water temperature cause deflection of the ring vacuum chamber which have in turn been shown to induce very small angular rotations of the magnets, on the order of 10 micro-radians. A larger and more difficult to correct effect is the drift in beam position over the course of a fill. This problem has been shown to be related to the thermal gradients that develop across the vacuum chamber which, as a consequence of the configuration of the chamber cooling, depend upon stored current. Orbit simulations based upon the measured rotations are in agreement with the observed beam motions, and reveal that certain patterns of correlated motions of the magnets can produce much larger errors than random motion or concerted motion of all the magnets. During the course of these measurements global orbit feedback was installed, and found to significantly reduce the orbit errors which could not be corrected at their source

  15. Immediate changes in widespread pressure pain sensitivity, neck pain, and cervical range of motion after cervical or thoracic thrust manipulation in patients with bilateral chronic mechanical neck pain: a randomized clinical trial.

    Science.gov (United States)

    Martínez-Segura, Raquel; De-la-Llave-Rincón, Ana I; Ortega-Santiago, Ricardo; Cleland, Joshua A; Fernández-de-Las-Peñas, César

    2012-09-01

    Randomized clinical trial. To compare the effects of cervical versus thoracic thrust manipulation in patients with bilateral chronic mechanical neck pain on pressure pain sensitivity, neck pain, and cervical range of motion (CROM). Evidence suggests that spinal interventions can stimulate descending inhibitory pain pathways. To our knowledge, no study has investigated the neurophysiological effects of thoracic thrust manipulation in individuals with bilateral chronic mechanical neck pain, including widespread changes on pressure sensitivity. Ninety patients (51% female) were randomly assigned to 1 of 3 groups: cervical thrust manipulation on the right, cervical thrust manipulation on the left, or thoracic thrust manipulation. Pressure pain thresholds (PPTs) over the C5-6 zygapophyseal joint, lateral epicondyle, and tibialis anterior muscle, neck pain (11-point numeric pain rating scale), and cervical spine range of motion (CROM) were collected at baseline and 10 minutes after the intervention by an assessor blinded to the treatment allocation of the patients. Mixed-model analyses of covariance were used to examine the effects of the treatment on each outcome variable, with group as the between-subjects variable, time and side as the within-subject variables, and gender as the covariate. The primary analysis was the group-by-time interaction. No significant interactions were found with the mixed-model analyses of covariance for PPT level (C5-6, P>.210; lateral epicondyle, P>.186; tibialis anterior muscle, P>.268), neck pain intensity (P = .923), or CROM (flexion, P = .700; extension, P = .387; lateral flexion, P>.672; rotation, P>.192) as dependent variables. All groups exhibited similar changes in PPT, neck pain, and CROM (all, P.10). The results of the current randomized clinical trial suggest that cervical and thoracic thrust manipulation induce similar changes in PPT, neck pain intensity, and CROM in individuals with bilateral chronic mechanical neck pain

  16. Topics in random walks in random environment

    International Nuclear Information System (INIS)

    Sznitman, A.-S.

    2004-01-01

    Over the last twenty-five years random motions in random media have been intensively investigated and some new general methods and paradigms have by now emerged. Random walks in random environment constitute one of the canonical models of the field. However in dimension bigger than one they are still poorly understood and many of the basic issues remain to this day unresolved. The present series of lectures attempt to give an account of the progresses which have been made over the last few years, especially in the study of multi-dimensional random walks in random environment with ballistic behavior. (author)

  17. Conserved linear dynamics of single-molecule Brownian motion

    KAUST Repository

    Serag, Maged F.

    2017-06-06

    Macromolecular diffusion in homogeneous fluid at length scales greater than the size of the molecule is regarded as a random process. The mean-squared displacement (MSD) of molecules in this regime increases linearly with time. Here we show that non-random motion of DNA molecules in this regime that is undetectable by the MSD analysis can be quantified by characterizing the molecular motion relative to a latticed frame of reference. Our lattice occupancy analysis reveals unexpected sub-modes of motion of DNA that deviate from expected random motion in the linear, diffusive regime. We demonstrate that a subtle interplay between these sub-modes causes the overall diffusive motion of DNA to appear to conform to the linear regime. Our results show that apparently random motion of macromolecules could be governed by non-random dynamics that are detectable only by their relative motion. Our analytical approach should advance broad understanding of diffusion processes of fundamental relevance.

  18. Conserved linear dynamics of single-molecule Brownian motion

    Science.gov (United States)

    Serag, Maged F.; Habuchi, Satoshi

    2017-06-01

    Macromolecular diffusion in homogeneous fluid at length scales greater than the size of the molecule is regarded as a random process. The mean-squared displacement (MSD) of molecules in this regime increases linearly with time. Here we show that non-random motion of DNA molecules in this regime that is undetectable by the MSD analysis can be quantified by characterizing the molecular motion relative to a latticed frame of reference. Our lattice occupancy analysis reveals unexpected sub-modes of motion of DNA that deviate from expected random motion in the linear, diffusive regime. We demonstrate that a subtle interplay between these sub-modes causes the overall diffusive motion of DNA to appear to conform to the linear regime. Our results show that apparently random motion of macromolecules could be governed by non-random dynamics that are detectable only by their relative motion. Our analytical approach should advance broad understanding of diffusion processes of fundamental relevance.

  19. Conserved linear dynamics of single-molecule Brownian motion

    KAUST Repository

    Serag, Maged F.; Habuchi, Satoshi

    2017-01-01

    Macromolecular diffusion in homogeneous fluid at length scales greater than the size of the molecule is regarded as a random process. The mean-squared displacement (MSD) of molecules in this regime increases linearly with time. Here we show that non-random motion of DNA molecules in this regime that is undetectable by the MSD analysis can be quantified by characterizing the molecular motion relative to a latticed frame of reference. Our lattice occupancy analysis reveals unexpected sub-modes of motion of DNA that deviate from expected random motion in the linear, diffusive regime. We demonstrate that a subtle interplay between these sub-modes causes the overall diffusive motion of DNA to appear to conform to the linear regime. Our results show that apparently random motion of macromolecules could be governed by non-random dynamics that are detectable only by their relative motion. Our analytical approach should advance broad understanding of diffusion processes of fundamental relevance.

  20. Effectiveness of a School-Based Physical Activity Intervention on Cognitive Performance in Danish Adolescents: LCoMotion—Learning, Cognition and Motion – A Cluster Randomized Controlled Trial

    Science.gov (United States)

    Domazet, Sidsel Louise; Froberg, Karsten; Hillman, Charles H.; Andersen, Lars Bo; Bugge, Anna

    2016-01-01

    Background Physical activity is associated not only with health-related parameters, but also with cognitive and academic performance. However, no large scale school-based physical activity interventions have investigated effects on cognitive performance in adolescents. The aim of this study was to describe the effectiveness of a school-based physical activity intervention in enhancing cognitive performance in 12–14 years old adolescents. Methods A 20 week cluster randomized controlled trial was conducted including seven intervention and seven control schools. A total of 632 students (mean (SD) age: 12.9 (0.6) years) completed the trial with baseline and follow-up data on primary or secondary outcomes (74% of randomized subjects). The intervention targeted physical activity during academic subjects, recess, school transportation and leisure-time. Cognitive performance was assessed using an executive functions test of inhibition (flanker task) with the primary outcomes being accuracy and reaction time on congruent and incongruent trials. Secondary outcomes included mathematics performance, physical activity levels, body-mass index, waist-circumference and cardiorespiratory fitness. Results No significant difference in change, comparing the intervention group to the control group, was observed on the primary outcomes (p’s>0.05) or mathematics skills (p>0.05). An intervention effect was found for cardiorespiratory fitness in girls (21 meters (95% CI: 4.4–38.6) and body-mass index in boys (-0.22 kg/m2 (95% CI: -0.39–0.05). Contrary to our predictions, a significantly larger change in interference control for reaction time was found in favor of the control group (5.0 milliseconds (95% CI: 0–9). Baseline to mid-intervention changes in physical activity levels did not differ significantly between groups (all p’s>0.05). Conclusions No evidence was found for effectiveness of a 20-week multi-faceted school-based physical activity intervention for enhancing

  1. Apatite fission track analysis: geological thermal history analysis based on a three-dimensional random process of linear radiation damage

    International Nuclear Information System (INIS)

    Galbraith, R.F.; Laslett, G.M.; Green, P.F.; Duddy, I.R.

    1990-01-01

    Spontaneous fission of uranium atoms over geological time creates a random process of linearly shaped features (fission tracks) inside an apatite crystal. The theoretical distributions associated with this process are governed by the elapsed time and temperature history, but other factors are also reflected in empirical measurements as consequences of sampling by plane section and chemical etching. These include geometrical biases leading to over-representation of long tracks, the shape and orientation of host features when sampling totally confined tracks, and 'gaps' in heavily annealed tracks. We study the estimation of geological parameters in the presence of these factors using measurements on both confined tracks and projected semi-tracks. Of particular interest is a history of sedimentation, uplift and erosion giving rise to a two-component mixture of tracks in which the parameters reflect the current temperature, the maximum temperature and the timing of uplift. A full likelihood analysis based on all measured densities, lengths and orientations is feasible, but because some geometrical biases and measurement limitations are only partly understood it seems preferable to use conditional likelihoods given numbers and orientations of confined tracks. (author)

  2. Randomized controlled trial of increasing physical activity on objectively measured and self-reported cognitive functioning among breast cancer survivors: The memory & motion study.

    Science.gov (United States)

    Hartman, Sheri J; Nelson, Sandahl H; Myers, Emily; Natarajan, Loki; Sears, Dorothy D; Palmer, Barton W; Weiner, Lauren S; Parker, Barbara A; Patterson, Ruth E

    2018-01-01

    Increasing physical activity can improve cognition in healthy and cognitively impaired adults; however, the benefits for cancer survivors are unknown. The current study examined a 12-week physical activity intervention, compared with a control condition, on objective and self-reported cognition among breast cancer survivors. Sedentary breast cancer survivors were randomized to an exercise arm (n = 43) or a control arm (n = 44). At baseline and at 12 weeks, objective cognition was measured with the National Institutes of Health Cognitive Toolbox, and self-reported cognition using the Patient-Reported Outcomes Measurement Information System scales. Linear mixed-effects regression models tested intervention effects for changes in cognition scores. On average, participants (n = 87) were aged 57 years (standard deviation, 10.4 years) and were 2.5 years (standard deviation, 1.3 years) post surgery. Scores on the Oral Symbol Digit subscale (a measure of processing speed) evidenced differential improvement in the exercise arm versus the control arm (b = 2.01; P cognition were not statistically significant but were suggestive of potential group differences. Time since surgery moderated the correlation, and participants who were ≤2 years post surgery had a significantly greater improvement in Oral Symbol Digit score (exercise vs control (b = 4.00; P 2 years postsurgery (b = -1.19; P = .40). A significant dose response was observed with greater increased physical activity associated with objective and self-reported cognition in the exercise arm. The exercise intervention significantly improved processing speed, but only among those who had been diagnosed with breast cancer within the past 2 years. Slowed processing speed can have substantial implications for independent functioning, supporting the potential importance of early implementation of an exercise intervention among patients with breast cancer. Cancer 2018;124:192-202. © 2017

  3. Estimation of Motion Vector Fields

    DEFF Research Database (Denmark)

    Larsen, Rasmus

    1993-01-01

    This paper presents an approach to the estimation of 2-D motion vector fields from time varying image sequences. We use a piecewise smooth model based on coupled vector/binary Markov random fields. We find the maximum a posteriori solution by simulated annealing. The algorithm generate sample...... fields by means of stochastic relaxation implemented via the Gibbs sampler....

  4. Influence of cooling rate in planar thermally assisted magnetic random access memory: Improved writeability due to spin-transfer-torque influence

    International Nuclear Information System (INIS)

    Chavent, A.; Ducruet, C.; Portemont, C.; Creuzet, C.; Alvarez-Hérault, J.; Vila, L.; Sousa, R. C.; Prejbeanu, I. L.; Dieny, B.

    2015-01-01

    This paper investigates the effect of a controlled cooling rate on magnetic field reversal assisted by spin transfer torque (STT) in thermally assisted magnetic random access memory. By using a gradual linear decrease of the voltage at the end of the write pulse, the STT decays more slowly or at least at the same rate as the temperature. This condition is necessary to make sure that the storage layer magnetization remains in the desired written direction during cooling of the cell. The influence of the write current pulse decay rate was investigated on two exchange biased synthetic ferrimagnet (SyF) electrodes. For a NiFe based electrode, a significant improvement in writing reproducibility was observed using a gradual linear voltage transition. The write error rate decreases by a factor of 10 when increasing the write pulse fall-time from ∼3 ns to 70 ns. For comparison, a second CoFe/NiFe based electrode was also reversed by magnetic field assisted by STT. In this case, no difference between sharp and linear write pulse fall shape was observed. We attribute this observation to the higher thermal stability of the CoFe/NiFe electrode during cooling. In real-time measurements of the magnetization reversal, it was found that Ruderman-Kittel-Kasuya-Yosida (RKKY) coupling in the SyF electrode vanishes for the highest pulse voltages that were used due to the high temperature reached during write. As a result, during the cooling phase, the final state is reached through a spin-flop transition of the SyF storage layer

  5. Motion planning for gantry mounted manipulators

    DEFF Research Database (Denmark)

    Olsen, Anders Lau; Petersen, Henrik Gordon

    2007-01-01

    We present a roadmap based planner for finding robot motions for gantry mounted manipulators for a line welding application at Odense Steel Shipyard (OSS). The robot motions are planned subject to constraints on when the gantry may be moved. We show that random sampling of gantry configurations...

  6. Auditory Motion Elicits a Visual Motion Aftereffect

    Directory of Open Access Journals (Sweden)

    Christopher C. Berger

    2016-12-01

    Full Text Available The visual motion aftereffect is a visual illusion in which exposure to continuous motion in one direction leads to a subsequent illusion of visual motion in the opposite direction. Previous findings have been mixed with regard to whether this visual illusion can be induced cross-modally by auditory stimuli. Based on research on multisensory perception demonstrating the profound influence auditory perception can have on the interpretation and perceived motion of visual stimuli, we hypothesized that exposure to auditory stimuli with strong directional motion cues should induce a visual motion aftereffect. Here, we demonstrate that horizontally moving auditory stimuli induced a significant visual motion aftereffect—an effect that was driven primarily by a change in visual motion perception following exposure to leftward moving auditory stimuli. This finding is consistent with the notion that visual and auditory motion perception rely on at least partially overlapping neural substrates.

  7. Auditory Motion Elicits a Visual Motion Aftereffect.

    Science.gov (United States)

    Berger, Christopher C; Ehrsson, H Henrik

    2016-01-01

    The visual motion aftereffect is a visual illusion in which exposure to continuous motion in one direction leads to a subsequent illusion of visual motion in the opposite direction. Previous findings have been mixed with regard to whether this visual illusion can be induced cross-modally by auditory stimuli. Based on research on multisensory perception demonstrating the profound influence auditory perception can have on the interpretation and perceived motion of visual stimuli, we hypothesized that exposure to auditory stimuli with strong directional motion cues should induce a visual motion aftereffect. Here, we demonstrate that horizontally moving auditory stimuli induced a significant visual motion aftereffect-an effect that was driven primarily by a change in visual motion perception following exposure to leftward moving auditory stimuli. This finding is consistent with the notion that visual and auditory motion perception rely on at least partially overlapping neural substrates.

  8. Auditory motion capturing ambiguous visual motion

    Directory of Open Access Journals (Sweden)

    Arjen eAlink

    2012-01-01

    Full Text Available In this study, it is demonstrated that moving sounds have an effect on the direction in which one sees visual stimuli move. During the main experiment sounds were presented consecutively at four speaker locations inducing left- or rightwards auditory apparent motion. On the path of auditory apparent motion, visual apparent motion stimuli were presented with a high degree of directional ambiguity. The main outcome of this experiment is that our participants perceived visual apparent motion stimuli that were ambiguous (equally likely to be perceived as moving left- or rightwards more often as moving in the same direction than in the opposite direction of auditory apparent motion. During the control experiment we replicated this finding and found no effect of sound motion direction on eye movements. This indicates that auditory motion can capture our visual motion percept when visual motion direction is insufficiently determinate without affecting eye movements.

  9. Motion control report

    CERN Document Server

    2013-01-01

    Please note this is a short discount publication. In today's manufacturing environment, Motion Control plays a major role in virtually every project.The Motion Control Report provides a comprehensive overview of the technology of Motion Control:* Design Considerations* Technologies* Methods to Control Motion* Examples of Motion Control in Systems* A Detailed Vendors List

  10. Capillary waves in slow motion

    International Nuclear Information System (INIS)

    Seydel, Tilo; Tolan, Metin; Press, Werner; Madsen, Anders; Gruebel, Gerhard

    2001-01-01

    Capillary wave dynamics on glycerol surfaces has been investigated by means of x-ray photon correlation spectroscopy performed at grazing angles. The measurements show that thermally activated capillary wave motion is slowed down exponentially when the sample is cooled below 273 K. This finding directly reflects the freezing of the surface waves. The wave-number dependence of the measured time constants is in quantitative agreement with theoretical predictions for overdamped capillary waves

  11. WORKSHOP: Stable particle motion

    International Nuclear Information System (INIS)

    Ruggiero, Alessandro G.

    1993-01-01

    Full text: Particle beam stability is crucial to any accelerator or collider, particularly big ones, such as Brookhaven's RHIC heavy ion collider and the larger SSC and LHC proton collider schemes. A workshop on the Stability of Particle Motion in Storage Rings held at Brookhaven in October dealt with the important issue of determining the short- and long-term stability of single particle motion in hadron storage rings and colliders, and explored new methods for ensuring it. In the quest for realistic environments, the imperfections of superconducting magnets and the effects of field modulation and noise were taken into account. The workshop was divided into three study groups: Short-Term Stability in storage rings, including chromatic and geometric effects and correction strategies; Long-Term Stability, including modulation and random noise effects and slow varying effects; and Methods for determining the stability of particle motion. The first two were run in parallel, but the third was attended by everyone. Each group considered analytical, computational and experimental methods, reviewing work done so far, comparing results and approaches and underlining outstanding issues. By resolving conflicts, it was possible to identify problems of common interest. The workshop reaffirmed the validity of methods proposed several years ago. Major breakthroughs have been in the rapid improvement of computer capacity and speed, in the development of more sophisticated mathematical packages, and in the introduction of more powerful analytic approaches. In a typical storage ring, a particle may be required to circulate for about a billion revolutions. While ten years ago it was only possible to predict accurately stability over about a thousand revolutions, it is now possible to predict over as many as one million turns. If this trend continues, in ten years it could become feasible to predict particle stability over the entire storage period. About ninety participants

  12. Biasing the random walk of a molecular motor

    Energy Technology Data Exchange (ETDEWEB)

    Astumian, R Dean [Department of Physics, University of Maine, Orono, ME 04469-5709 (United States)

    2005-11-30

    Biomolecular motors are often described in mechanical terms, with analogy to cars, turbines, judo throws, levers, etc. It is important to remember however that because of their small size, and because of the aqueous environment in which molecular motors move, viscous drag and thermal noise dominate the inertial forces that drive macroscopic machines. The sequence of motions-conformational changes-by which a motor protein moves can best be described as a random walk, with transitions from one state to another occurring by thermal activation over energy barriers. In this paper I will address the question of how this random walk is biased by a non-equilibrium chemical reaction (ATP hydrolysis) so that the motor molecule moves preferentially (with almost unit certainty) in one direction, even when an external force is applied to drive it in the opposite direction. I will also discuss how these 'soft matter' motors can achieve thermodynamic efficiencies of nearly 100%.

  13. Biasing the random walk of a molecular motor

    International Nuclear Information System (INIS)

    Astumian, R Dean

    2005-01-01

    Biomolecular motors are often described in mechanical terms, with analogy to cars, turbines, judo throws, levers, etc. It is important to remember however that because of their small size, and because of the aqueous environment in which molecular motors move, viscous drag and thermal noise dominate the inertial forces that drive macroscopic machines. The sequence of motions-conformational changes-by which a motor protein moves can best be described as a random walk, with transitions from one state to another occurring by thermal activation over energy barriers. In this paper I will address the question of how this random walk is biased by a non-equilibrium chemical reaction (ATP hydrolysis) so that the motor molecule moves preferentially (with almost unit certainty) in one direction, even when an external force is applied to drive it in the opposite direction. I will also discuss how these 'soft matter' motors can achieve thermodynamic efficiencies of nearly 100%

  14. Motion in radiotherapy

    DEFF Research Database (Denmark)

    Korreman, Stine Sofia

    2012-01-01

    This review considers the management of motion in photon radiation therapy. An overview is given of magnitudes and variability of motion of various structures and organs, and how the motion affects images by producing artifacts and blurring. Imaging of motion is described, including 4DCT and 4DPE...

  15. Diffusion-advection within dynamic biological gaps driven by structural motion

    Science.gov (United States)

    Asaro, Robert J.; Zhu, Qiang; Lin, Kuanpo

    2018-04-01

    To study the significance of advection in the transport of solutes, or particles, within thin biological gaps (channels), we examine theoretically the process driven by stochastic fluid flow caused by random thermal structural motion, and we compare it with transport via diffusion. The model geometry chosen resembles the synaptic cleft; this choice is motivated by the cleft's readily modeled structure, which allows for well-defined mechanical and physical features that control the advection process. Our analysis defines a Péclet-like number, AD, that quantifies the ratio of time scales of advection versus diffusion. Another parameter, AM, is also defined by the analysis that quantifies the full potential extent of advection in the absence of diffusion. These parameters provide a clear and compact description of the interplay among the well-defined structural, geometric, and physical properties vis-a ̀-vis the advection versus diffusion process. For example, it is found that AD˜1 /R2 , where R is the cleft diameter and hence diffusion distance. This curious, and perhaps unexpected, result follows from the dependence of structural motion that drives fluid flow on R . AM, on the other hand, is directly related (essentially proportional to) the energetic input into structural motion, and thereby to fluid flow, as well as to the mechanical stiffness of the cleftlike structure. Our model analysis thus provides unambiguous insight into the prospect of competition of advection versus diffusion within biological gaplike structures. The importance of the random, versus a regular, nature of structural motion and of the resulting transient nature of advection under random motion is made clear in our analysis. Further, by quantifying the effects of geometric and physical properties on the competition between advection and diffusion, our results clearly demonstrate the important role that metabolic energy (ATP) plays in this competitive process.

  16. Motion Transplantation Techniques: A Survey

    NARCIS (Netherlands)

    van Basten, Ben; Egges, Arjan

    2012-01-01

    During the past decade, researchers have developed several techniques for transplanting motions. These techniques transplant a partial auxiliary motion, possibly defined for a small set of degrees of freedom, on a base motion. Motion transplantation improves motion databases' expressiveness and

  17. Anomalous Brownian motion of colloidal particle in a nematic environment: effect of the director fluctuations

    Directory of Open Access Journals (Sweden)

    T. Turiv

    2015-06-01

    Full Text Available As recently reported [Turiv T. et al., Science, 2013, Vol. 342, 1351], fluctuations in the orientation of the liquid crystal (LC director can transfer momentum from the LC to a colloid, such that the diffusion of the colloid becomes anomalous on a short time scale. Using video microscopy and single particle tracking, we investigate random thermal motion of colloidal particles in a nematic liquid crystal for the time scales shorter than the expected time of director fluctuations. At long times, compared to the characteristic time of the nematic director relaxation we observe typical anisotropic Brownian motion with the mean square displacement (MSD linear in time τ and inversly proportional to the effective viscosity of the nematic medium. At shorter times, however, the dynamics is markedly nonlinear with MSD growing more slowly (subdiffusion or faster (superdiffusion than τ. These results are discussed in the context of coupling of colloidal particle's dynamics to the director fluctuation dynamics.

  18. Nano-motion dynamics are determined by surface-tethered selectin mechanokinetics and bond formation.

    Directory of Open Access Journals (Sweden)

    Brian J Schmidt

    2009-12-01

    -dimensional bond formation gained from flow cell assays might therefore be important to understand processes involving extended cellular interactions, such as immunological synapse formation. A biologically informative in silico system was created with minimal, high-confidence inputs. Incorporating random effects in surface separation through thermal motion enabled new deductions of the effects of surface-constrained biomolecular function. Important molecular information is embedded in the patterns and statistics of motion.

  19. Phonon assisted thermophoretic motion of gold nanoparticles inside carbon nanotubes

    DEFF Research Database (Denmark)

    Schoen, Philipp A.E.; Walther, Jens Honore; Poulikakos, Dimos

    2007-01-01

    The authors investigate the thermally driven mass transport of gold nanoparticles confined inside carbon nanotubes using molecular dynamics simulations. The observed thermophoretic motion of the gold nanoparticles correlates with the phonon dispersion exhibited by a standard carbon nanotube and...

  20. Attention and apparent motion.

    Science.gov (United States)

    Horowitz, T; Treisman, A

    1994-01-01

    Two dissociations between short- and long-range motion in visual search are reported. Previous research has shown parallel processing for short-range motion and apparently serial processing for long-range motion. This finding has been replicated and it has also been found that search for short-range targets can be impaired both by using bicontrast stimuli, and by prior adaptation to the target direction of motion. Neither factor impaired search in long-range motion displays. Adaptation actually facilitated search with long-range displays, which is attributed to response-level effects. A feature-integration account of apparent motion is proposed. In this theory, short-range motion depends on specialized motion feature detectors operating in parallel across the display, but subject to selective adaptation, whereas attention is needed to link successive elements when they appear at greater separations, or across opposite contrasts.

  1. Sound-contingent visual motion aftereffect

    Directory of Open Access Journals (Sweden)

    Kobayashi Maori

    2011-05-01

    Full Text Available Abstract Background After a prolonged exposure to a paired presentation of different types of signals (e.g., color and motion, one of the signals (color becomes a driver for the other signal (motion. This phenomenon, which is known as contingent motion aftereffect, indicates that the brain can establish new neural representations even in the adult's brain. However, contingent motion aftereffect has been reported only in visual or auditory domain. Here, we demonstrate that a visual motion aftereffect can be contingent on a specific sound. Results Dynamic random dots moving in an alternating right or left direction were presented to the participants. Each direction of motion was accompanied by an auditory tone of a unique and specific frequency. After a 3-minutes exposure, the tones began to exert marked influence on the visual motion perception, and the percentage of dots required to trigger motion perception systematically changed depending on the tones. Furthermore, this effect lasted for at least 2 days. Conclusions These results indicate that a new neural representation can be rapidly established between auditory and visual modalities.

  2. Brownian motion using video capture

    International Nuclear Information System (INIS)

    Salmon, Reese; Robbins, Candace; Forinash, Kyle

    2002-01-01

    Although other researchers had previously observed the random motion of pollen grains suspended in water through a microscope, Robert Brown's name is associated with this behaviour based on observations he made in 1828. It was not until Einstein's work in the early 1900s however, that the origin of this irregular motion was established to be the result of collisions with molecules which were so small as to be invisible in a light microscope (Einstein A 1965 Investigations on the Theory of the Brownian Movement ed R Furth (New York: Dover) (transl. Cowper A D) (5 papers)). Jean Perrin in 1908 (Perrin J 1923 Atoms (New York: Van Nostrand-Reinhold) (transl. Hammick D)) was able, through a series of painstaking experiments, to establish the validity of Einstein's equation. We describe here the details of a junior level undergraduate physics laboratory experiment where students used a microscope, a video camera and video capture software to verify Einstein's famous calculation of 1905. (author)

  3. Objects in Motion

    Science.gov (United States)

    Damonte, Kathleen

    2004-01-01

    One thing scientists study is how objects move. A famous scientist named Sir Isaac Newton (1642-1727) spent a lot of time observing objects in motion and came up with three laws that describe how things move. This explanation only deals with the first of his three laws of motion. Newton's First Law of Motion says that moving objects will continue…

  4. Motion compensated digital tomosynthesis

    NARCIS (Netherlands)

    van der Reijden, Anneke; van Herk, Marcel; Sonke, Jan-Jakob

    2013-01-01

    Digital tomosynthesis (DTS) is a limited angle image reconstruction method for cone beam projections that offers patient surveillance capabilities during VMAT based SBRT delivery. Motion compensation (MC) has the potential to mitigate motion artifacts caused by respiratory motion, such as blur. The

  5. Rolling Shutter Motion Deblurring

    KAUST Repository

    Su, Shuochen

    2015-06-07

    Although motion blur and rolling shutter deformations are closely coupled artifacts in images taken with CMOS image sensors, the two phenomena have so far mostly been treated separately, with deblurring algorithms being unable to handle rolling shutter wobble, and rolling shutter algorithms being incapable of dealing with motion blur. We propose an approach that delivers sharp and undis torted output given a single rolling shutter motion blurred image. The key to achieving this is a global modeling of the camera motion trajectory, which enables each scanline of the image to be deblurred with the corresponding motion segment. We show the results of the proposed framework through experiments on synthetic and real data.

  6. Smoothing Motion Estimates for Radar Motion Compensation.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-07-01

    Simple motion models for complex motion environments are often not adequate for keeping radar data coherent. Eve n perfect motion samples appli ed to imperfect models may lead to interim calculations e xhibiting errors that lead to degraded processing results. Herein we discuss a specific i ssue involving calculating motion for groups of pulses, with measurements only available at pulse-group boundaries. - 4 - Acknowledgements This report was funded by General A tomics Aeronautical Systems, Inc. (GA-ASI) Mission Systems under Cooperative Re search and Development Agre ement (CRADA) SC08/01749 between Sandia National Laboratories and GA-ASI. General Atomics Aeronautical Systems, Inc. (GA-ASI), an affilia te of privately-held General Atomics, is a leading manufacturer of Remotely Piloted Aircraft (RPA) systems, radars, and electro-optic and rel ated mission systems, includin g the Predator(r)/Gray Eagle(r)-series and Lynx(r) Multi-mode Radar.

  7. Curves from Motion, Motion from Curves

    Science.gov (United States)

    2000-01-01

    De linearum curvarum cum lineis rectis comparatione dissertatio geometrica - an appendix to a treatise by de Lalouv~re (this was the only publication... correct solution to the problem of motion in the gravity of a permeable rotating Earth, considered by Torricelli (see §3). If the Earth is a homogeneous...in 1686, which contains the correct solution as part of a remarkably comprehensive theory of orbital motions under centripetal forces. It is a

  8. Structural motion engineering

    CERN Document Server

    Connor, Jerome

    2014-01-01

    This innovative volume provides a systematic treatment of the basic concepts and computational procedures for structural motion design and engineering for civil installations. The authors illustrate the application of motion control to a wide spectrum of buildings through many examples. Topics covered include optimal stiffness distributions for building-type structures, the role of damping in controlling motion, tuned mass dampers, base isolation systems, linear control, and nonlinear control. The book's primary objective is the satisfaction of motion-related design requirements, such as restrictions on displacement and acceleration. The book is ideal for practicing engineers and graduate students. This book also: ·         Broadens practitioners' understanding of structural motion control, the enabling technology for motion-based design ·         Provides readers the tools to satisfy requirements of modern, ultra-high strength materials that lack corresponding stiffness, where the motion re...

  9. Confirmation, refinement, and extension of a study in intrafraction motion interplay with sliding jaw motion

    International Nuclear Information System (INIS)

    Kissick, Michael W.; Boswell, Sarah A.; Jeraj, Robert; Mackie, T. Rockwell

    2005-01-01

    The interplay between a constant scan speed and intrafraction oscillatory motion produces interesting fluence intensity modulations along the axis of motion that are sensitive to the motion function, as originally shown in a classic paper by Yu et al. [Phys. Med. Biol. 43, 91-104 (1998)]. The fluence intensity profiles are explored in this note for an intuitive understanding, then compared with Yu et al., and finally further explored for the effects of low scan speed and random components of both intrafraction and interfraction motion. At slow scan speeds typical of helical tomotherapy, these fluence intensity modulations are only a few percent. With the addition of only a small amount of cycle-to-cycle randomness in frequency and amplitude, the fluence intensity profiles change dramatically. It is further shown that after a typical 30-fraction treatment, the sensitivities displayed in the single fraction fluence intensity profiles greatly diminish

  10. Unilateral Versus Bilateral Laparoscopic Ovarian Drilling Using Thermal Dose Adjusted According to Ovarian Volume in CC-Resistant PCOS, A Randomized Study.

    Science.gov (United States)

    El-Sayed, Mohamed Lotfy Mohamed; Ahmed, Mostafa Abdo; Mansour, Marwa Abdel Azim; Mansour, Shymma Abdel Azim

    2017-10-01

    This study aimed to evaluate the efficacy of unilateral laparoscopic ovarian drilling versus bilateral laparoscopic ovarian drilling with thermal dose adjusted according to ovarian volume in clomiphene citrate (CC)-resistant PCOS patients in terms of endocrine changes, menstrual cycle resumption, ovulation and pregnancy rates. This study was conducted in the Department of Obstetrics and Gynecology, Zagazig university hospitals. One hundred CC-resistant PCOS patients were divided into two groups. Group (I) (50 patients) underwent unilateral laparoscopic ovarian drilling with thermal dose adjusted according to ovarian volume (60 J/cm 3 of ovarian tissue), and group (II) (50 patients) underwent bilateral laparoscopic ovarian drilling using the same previously mentioned thermal dose. Endocrinal changes and menstrual cycle resumption were assessed within 8 weeks postoperatively, but the ovulation and pregnancy rates were estimated after 6-month follow-up period. There was no statistically significant difference between the two groups as regards demographic data ( p  > 0.05). As regards menstruation cycle resumption (62.5 vs. 81%) ( p  = 0.047), total ovulation rate (54.2 vs. 78.7%) ( p  = 0.011) and cumulative pregnancy rate (33.3 vs. 55.3%) ( p  = 0.031), there was statistically significant difference between both groups. After drilling, there were highly statistically significant decrease in the mean serum levels of luteinizing hormone (LH) and significant decrease in the mean serum levels of testosterone in both groups. Mean serum level of follicle stimulating hormone (FSH) did not change significantly in both groups after drilling. Bilateral laparoscopic ovarian drilling with thermal dose adjusted according to ovarian volume is more effective than the right-sided unilateral technique with thermal dose adjusted according to ovarian volume in terms of menstrual cycle resumption, ovulation and cumulative pregnancy rates in CC-resistant PCOS patients.

  11. Real-Time Motion Management of Prostate Cancer Radiotherapy

    DEFF Research Database (Denmark)

    Pommer, Tobias

    , and for prostate cancer treatments, the proximity of the bladder and rectum makes radiotherapy treatment of this site a challenging task. Furthermore, the prostate may move during the radiation delivery and treatment margins are necessary to ensure that it is still receiving the intended dose. The main aim...... of the MLC on the performance of DMLC tracking were investigated. We found that for prostate motion, the main tracking error arose from the finite leaf width affecting the MLCs ability to construct the desired shape. Furthermore, we also attempted to model prostate motion using a random walk model. We found...... that for the slow and drifting motion, the model could satisfactory replicate the motion of the prostate, while the rapid and transient prostate motion observed in some cases was challenging for the model. We therefore added simulated transient motion to the random walk model, which slightly improved the results...

  12. Thermal properties of the mixed spin-1 and spin-3/2 Ising ferrimagnetic system with two different random single-ion anisotropies

    Science.gov (United States)

    Pereira, J. R. V.; Tunes, T. M.; de Arruda, A. S.; Godoy, M.

    2018-06-01

    In this work, we have performed Monte Carlo simulations to study a mixed spin-1 and spin-3/2 Ising ferrimagnetic system on a square lattice with two different random single-ion anisotropies. This lattice is divided in two interpenetrating sublattices with spins SA = 1 in the sublattice A and SB = 3 / 2 in the sublattice B. The exchange interaction between the spins on the sublattices is antiferromagnetic (J single-ion anisotropies, DiA and DjB , on the sublattices A and B, respectively. We have determined the phase diagram of the model in the critical temperature Tc versus strength of the random single-ion anisotropy D plane and we shown that it exhibits only second-order phase transition lines. We also shown that this system displays compensation temperatures for some cases of the random single-ion distribution.

  13. Synchronization and collective motion of globally coupled Brownian particles

    International Nuclear Information System (INIS)

    Sevilla, Francisco J; Heiblum-Robles, Alexandro; Dossetti, Victor

    2014-01-01

    In this work, we study a system of passive Brownian (non-self-propelled) particles in two dimensions, interacting only through a social-like force (velocity alignment in this case) that resembles Kuramoto's coupling among phase oscillators. We show that the kinematical stationary states of the system go from a phase in thermal equilibrium with no net flux of particles, to far-from-equilibrium phases exhibiting collective motion by increasing the coupling among particles. The mechanism that leads to the instability of the equilibrium phase relies on the competition between two time scales, namely, the mean collision time of the Brownian particles in a thermal bath and the time it takes for a particle to orient its direction of motion along the direction of motion of the group. Our results show a clear connection between collective motion and the Kuramoto model for synchronization, in our case, for the direction of motion of the particles. (paper)

  14. Motion and relativity

    CERN Document Server

    Infeld, Leopold

    1960-01-01

    Motion and Relativity focuses on the methodologies, solutions, and approaches involved in the study of motion and relativity, including the general relativity theory, gravitation, and approximation.The publication first offers information on notation and gravitational interaction and the general theory of motion. Discussions focus on the notation of the general relativity theory, field values on the world-lines, general statement of the physical problem, Newton's theory of gravitation, and forms for the equation of motion of the second kind. The text then takes a look at the approximation meth

  15. Brain Image Motion Correction

    DEFF Research Database (Denmark)

    Jensen, Rasmus Ramsbøl; Benjaminsen, Claus; Larsen, Rasmus

    2015-01-01

    The application of motion tracking is wide, including: industrial production lines, motion interaction in gaming, computer-aided surgery and motion correction in medical brain imaging. Several devices for motion tracking exist using a variety of different methodologies. In order to use such devices...... offset and tracking noise in medical brain imaging. The data are generated from a phantom mounted on a rotary stage and have been collected using a Siemens High Resolution Research Tomograph for positron emission tomography. During acquisition the phantom was tracked with our latest tracking prototype...

  16. Rectified motion in an asymmetrically structured channel due to induced-charge electrokinetic and thermo-kinetic phenomena

    International Nuclear Information System (INIS)

    Sugioka, Hideyuki

    2016-01-01

    It would be advantageous to move fluid by the gradient of random thermal noises that are omnipresent in the natural world. To achieve this motion, we propose a rectifier that uses a thermal noise along with induced-charge electroosmosis and electrophoresis (ICEO and ICEP) around a metal post cylinder in an asymmetrically structured channel and numerically examine its rectification performance. By the boundary element method combined with the thin double layer approximation, we find that rectified motion occurs in the asymmetrically structured channel due to ICEO and ICEP. Further, by thermodynamical and equivalent circuit methods, we discuss a thermal voltage that drives a rectifier consisting of a fluidic channel of an electrolyte and an impedance as a noise source. Our calculations show that fluid can be moved in the asymmetrically structured channel by the fluctuation of electric fields due to a thermal noise only when there is a temperature difference. In addition, our simple noise argument provides a different perspective for the thermo-kinetic phenomena (around a metal post) which was predicted based on the electrolyte Seebeck effect in our previous paper [H. Sugioka, “Nonlinear thermokinetic phenomena due to the Seebeck effect,” Langmuir 30, 8621 (2014)

  17. Rectified motion in an asymmetrically structured channel due to induced-charge electrokinetic and thermo-kinetic phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Sugioka, Hideyuki, E-mail: hsugioka@shinshu-u.ac.jp [Frontier Research Center, Canon Inc. 30-2, Shimomaruko 3-chome, Ohta-ku, Tokyo 146-8501, Japan and Department of Mechanical Systems Engineering, Shinshu University 4-17-1 Wakasato, Nagano 380-8553 (Japan)

    2016-02-15

    It would be advantageous to move fluid by the gradient of random thermal noises that are omnipresent in the natural world. To achieve this motion, we propose a rectifier that uses a thermal noise along with induced-charge electroosmosis and electrophoresis (ICEO and ICEP) around a metal post cylinder in an asymmetrically structured channel and numerically examine its rectification performance. By the boundary element method combined with the thin double layer approximation, we find that rectified motion occurs in the asymmetrically structured channel due to ICEO and ICEP. Further, by thermodynamical and equivalent circuit methods, we discuss a thermal voltage that drives a rectifier consisting of a fluidic channel of an electrolyte and an impedance as a noise source. Our calculations show that fluid can be moved in the asymmetrically structured channel by the fluctuation of electric fields due to a thermal noise only when there is a temperature difference. In addition, our simple noise argument provides a different perspective for the thermo-kinetic phenomena (around a metal post) which was predicted based on the electrolyte Seebeck effect in our previous paper [H. Sugioka, “Nonlinear thermokinetic phenomena due to the Seebeck effect,” Langmuir 30, 8621 (2014)].

  18. Non-Fourier based thermal-mechanical tissue damage prediction for thermal ablation.

    Science.gov (United States)

    Li, Xin; Zhong, Yongmin; Smith, Julian; Gu, Chengfan

    2017-01-02

    Prediction of tissue damage under thermal loads plays important role for thermal ablation planning. A new methodology is presented in this paper by combing non-Fourier bio-heat transfer, constitutive elastic mechanics as well as non-rigid motion of dynamics to predict and analyze thermal distribution, thermal-induced mechanical deformation and thermal-mechanical damage of soft tissues under thermal loads. Simulations and comparison analysis demonstrate that the proposed methodology based on the non-Fourier bio-heat transfer can account for the thermal-induced mechanical behaviors of soft tissues and predict tissue thermal damage more accurately than classical Fourier bio-heat transfer based model.

  19. Directional Limits on Motion Transparency Assessed Through Colour-Motion Binding.

    Science.gov (United States)

    Maloney, Ryan T; Clifford, Colin W G; Mareschal, Isabelle

    2018-03-01

    Motion-defined transparency is the perception of two or more distinct moving surfaces at the same retinal location. We explored the limits of motion transparency using superimposed surfaces of randomly positioned dots defined by differences in motion direction and colour. In one experiment, dots were red or green and we varied the proportion of dots of a single colour that moved in a single direction ('colour-motion coherence') and measured the threshold direction difference for discriminating between two directions. When colour-motion coherences were high (e.g., 90% of red dots moving in one direction), a smaller direction difference was required to correctly bind colour with direction than at low coherences. In another experiment, we varied the direction difference between the surfaces and measured the threshold colour-motion coherence required to discriminate between them. Generally, colour-motion coherence thresholds decreased with increasing direction differences, stabilising at direction differences around 45°. Different stimulus durations were compared, and thresholds were higher at the shortest (150 ms) compared with the longest (1,000 ms) duration. These results highlight different yet interrelated aspects of the task and the fundamental limits of the mechanisms involved: the resolution of narrowly separated directions in motion processing and the local sampling of dot colours from each surface.

  20. Predictive local receptive fields based respiratory motion tracking for motion-adaptive radiotherapy.

    Science.gov (United States)

    Yubo Wang; Tatinati, Sivanagaraja; Liyu Huang; Kim Jeong Hong; Shafiq, Ghufran; Veluvolu, Kalyana C; Khong, Andy W H

    2017-07-01

    Extracranial robotic radiotherapy employs external markers and a correlation model to trace the tumor motion caused by the respiration. The real-time tracking of tumor motion however requires a prediction model to compensate the latencies induced by the software (image data acquisition and processing) and hardware (mechanical and kinematic) limitations of the treatment system. A new prediction algorithm based on local receptive fields extreme learning machines (pLRF-ELM) is proposed for respiratory motion prediction. All the existing respiratory motion prediction methods model the non-stationary respiratory motion traces directly to predict the future values. Unlike these existing methods, the pLRF-ELM performs prediction by modeling the higher-level features obtained by mapping the raw respiratory motion into the random feature space of ELM instead of directly modeling the raw respiratory motion. The developed method is evaluated using the dataset acquired from 31 patients for two horizons in-line with the latencies of treatment systems like CyberKnife. Results showed that pLRF-ELM is superior to that of existing prediction methods. Results further highlight that the abstracted higher-level features are suitable to approximate the nonlinear and non-stationary characteristics of respiratory motion for accurate prediction.

  1. Randomness at the root of things 1: Random walks

    Science.gov (United States)

    Ogborn, Jon; Collins, Simon; Brown, Mick

    2003-09-01

    This is the first of a pair of articles about randomness in physics. In this article, we use some variations on the idea of a `random walk' to consider first the path of a particle in Brownian motion, and then the random variation to be expected in radioactive decay. The arguments are set in the context of the general importance of randomness both in physics and in everyday life. We think that the ideas could usefully form part of students' A-level work on random decay and quantum phenomena, as well as being good for their general education. In the second article we offer a novel and simple approach to Poisson sequences.

  2. Fokker-Planck equation for the non-Markovian Brownian motion in the presence of a magnetic field

    Science.gov (United States)

    Das, Joydip; Mondal, Shrabani; Bag, Bidhan Chandra

    2017-10-01

    In the present study, we have proposed the Fokker-Planck equation in a simple way for a Langevin equation of motion having ordinary derivative (OD), the Gaussian random force and a generalized frictional memory kernel. The equation may be associated with or without conservative force field from harmonic potential. We extend this method for a charged Brownian particle in the presence of a magnetic field. Thus, the present method is applicable for a Langevin equation of motion with OD, the Gaussian colored thermal noise and any kind of linear force field that may be conservative or not. It is also simple to apply this method for the colored Gaussian noise that is not related to the damping strength.

  3. Projectile Motion Hoop Challenge

    Science.gov (United States)

    Jordan, Connor; Dunn, Amy; Armstrong, Zachary; Adams, Wendy K.

    2018-01-01

    Projectile motion is a common phenomenon that is used in introductory physics courses to help students understand motion in two dimensions. Authors have shared a range of ideas for teaching this concept and the associated kinematics in "The Physics Teacher" ("TPT"); however, the "Hoop Challenge" is a new setup not…

  4. Temporal logic motion planning

    CSIR Research Space (South Africa)

    Seotsanyana, M

    2010-01-01

    Full Text Available In this paper, a critical review on temporal logic motion planning is presented. The review paper aims to address the following problems: (a) In a realistic situation, the motion planning problem is carried out in real-time, in a dynamic, uncertain...

  5. Aristotle, Motion, and Rhetoric.

    Science.gov (United States)

    Sutton, Jane

    Aristotle rejects a world vision of changing reality as neither useful nor beneficial to human life, and instead he reaffirms both change and eternal reality, fuses motion and rest, and ends up with "well-behaved" changes. This concept of motion is foundational to his world view, and from it emerges his theory of knowledge, philosophy of…

  6. Quantifying motion for pancreatic radiotherapy margin calculation

    International Nuclear Information System (INIS)

    Whitfield, Gillian; Jain, Pooja; Green, Melanie; Watkins, Gillian; Henry, Ann; Stratford, Julie; Amer, Ali; Marchant, Thomas; Moore, Christopher; Price, Patricia

    2012-01-01

    Background and purpose: Pancreatic radiotherapy (RT) is limited by uncertain target motion. We quantified 3D patient/organ motion during pancreatic RT and calculated required treatment margins. Materials and methods: Cone-beam computed tomography (CBCT) and orthogonal fluoroscopy images were acquired post-RT delivery from 13 patients with locally advanced pancreatic cancer. Bony setup errors were calculated from CBCT. Inter- and intra-fraction fiducial (clip/seed/stent) motion was determined from CBCT projections and orthogonal fluoroscopy. Results: Using an off-line CBCT correction protocol, systematic (random) setup errors were 2.4 (3.2), 2.0 (1.7) and 3.2 (3.6) mm laterally (left–right), vertically (anterior–posterior) and longitudinally (cranio-caudal), respectively. Fiducial motion varied substantially. Random inter-fractional changes in mean fiducial position were 2.0, 1.6 and 2.6 mm; 95% of intra-fractional peak-to-peak fiducial motion was up to 6.7, 10.1 and 20.6 mm, respectively. Calculated clinical to planning target volume (CTV–PTV) margins were 1.4 cm laterally, 1.4 cm vertically and 3.0 cm longitudinally for 3D conformal RT, reduced to 0.9, 1.0 and 1.8 cm, respectively, if using 4D planning and online setup correction. Conclusions: Commonly used CTV–PTV margins may inadequately account for target motion during pancreatic RT. Our results indicate better immobilisation, individualised allowance for respiratory motion, online setup error correction and 4D planning would improve targeting.

  7. Stochastic ground motion simulation

    Science.gov (United States)

    Rezaeian, Sanaz; Xiaodan, Sun; Beer, Michael; Kougioumtzoglou, Ioannis A.; Patelli, Edoardo; Siu-Kui Au, Ivan

    2014-01-01

    Strong earthquake ground motion records are fundamental in engineering applications. Ground motion time series are used in response-history dynamic analysis of structural or geotechnical systems. In such analysis, the validity of predicted responses depends on the validity of the input excitations. Ground motion records are also used to develop ground motion prediction equations(GMPEs) for intensity measures such as spectral accelerations that are used in response-spectrum dynamic analysis. Despite the thousands of available strong ground motion records, there remains a shortage of records for large-magnitude earthquakes at short distances or in specific regions, as well as records that sample specific combinations of source, path, and site characteristics.

  8. The open quantum Brownian motions

    International Nuclear Information System (INIS)

    Bauer, Michel; Bernard, Denis; Tilloy, Antoine

    2014-01-01

    Using quantum parallelism on random walks as the original seed, we introduce new quantum stochastic processes, the open quantum Brownian motions. They describe the behaviors of quantum walkers—with internal degrees of freedom which serve as random gyroscopes—interacting with a series of probes which serve as quantum coins. These processes may also be viewed as the scaling limit of open quantum random walks and we develop this approach along three different lines: the quantum trajectory, the quantum dynamical map and the quantum stochastic differential equation. We also present a study of the simplest case, with a two level system as an internal gyroscope, illustrating the interplay between the ballistic and diffusive behaviors at work in these processes. Notation H z : orbital (walker) Hilbert space, C Z in the discrete, L 2 (R) in the continuum H c : internal spin (or gyroscope) Hilbert space H sys =H z ⊗H c : system Hilbert space H p : probe (or quantum coin) Hilbert space, H p =C 2 ρ t tot : density matrix for the total system (walker + internal spin + quantum coins) ρ-bar t : reduced density matrix on H sys : ρ-bar t =∫dxdy ρ-bar t (x,y)⊗|x〉 z 〈y| ρ-hat t : system density matrix in a quantum trajectory: ρ-hat t =∫dxdy ρ-hat t (x,y)⊗|x〉 z 〈y|. If diagonal and localized in position: ρ-hat t =ρ t ⊗|X t 〉 z 〈X t | ρ t : internal density matrix in a simple quantum trajectory X t : walker position in a simple quantum trajectory B t : normalized Brownian motion ξ t , ξ t † : quantum noises (paper)

  9. Effects of ship motions on laminar flow in tubes

    Energy Technology Data Exchange (ETDEWEB)

    Yan, B.H., E-mail: yanbh1986@163.co [Department of Nuclear Science and Engineering, Naval University of Engineering, 717 Jiefang Street, Wuhan 430033 (China); Yu, L. [Department of Nuclear Science and Engineering, Naval University of Engineering, 717 Jiefang Street, Wuhan 430033 (China); Yang, Y.H. [School of Nuclear Science and Engineering, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240 (China)

    2010-01-15

    The thermal-hydraulics of barge-mounted floating nuclear desalination plants is the incentive for this study. Laminar flow in tubes in heaving motion is modeled. The friction factor and heat transfer coefficient are obtained. All the equations of laminar flow in steady state are applicable for heeling motion. The effect of ship motions on the laminar developing region is also analyzed. The ship motions can weaken the boundary layer in the laminar developing region and strengthen the laminar frictional resistance. The effect of ship motions on the instability of laminar flow is also investigated. The ship motions do not affect the instability point, but they can shorten the distance between the instability point and the transition point, and cause the transition from laminar flow to turbulent flow to occur earlier.

  10. Measurement and Compensation of BPM Chamber Motion in HLS

    Science.gov (United States)

    Li, J. W.; Sun, B. G.; Cao, Y.; Xu, H. L.; Lu, P.; Li, C.; Xuan, K.; Wang, J. G.

    2010-06-01

    Significant horizontal drifts in the beam orbit in the storage ring of HLS (Hefei Light Source) have been seen for many years. What leads to the motion of Beam Position Monitor (BPM) chamber is thermal expansion mainly caused by the synchrotron light. To monitor the BPM chamber motions for all BPMs, a BPM chamber motion measurement system is built in real-time. The raster gauges are used to measure the displacements. The results distinctly show the relation between the BPM chamber motion and the beam current. To suppress the effect of BPM chamber motion, a compensation strategy is implemented at HLS. The horizontal drifts of beam orbit have been really suppressed within 20μm without the compensation of BPM chamber motion in the runtime.

  11. Measurement and Compensation of BPM Chamber Motion in HLS

    International Nuclear Information System (INIS)

    Li, J. W.; Sun, B. G.; Cao, Y.; Xu, H. L.; Lu, P.; Li, C.; Xuan, K.; Wang, J. G.

    2010-01-01

    Significant horizontal drifts in the beam orbit in the storage ring of HLS (Hefei Light Source) have been seen for many years. What leads to the motion of Beam Position Monitor (BPM) chamber is thermal expansion mainly caused by the synchrotron light. To monitor the BPM chamber motions for all BPMs, a BPM chamber motion measurement system is built in real-time. The raster gauges are used to measure the displacements. The results distinctly show the relation between the BPM chamber motion and the beam current. To suppress the effect of BPM chamber motion, a compensation strategy is implemented at HLS. The horizontal drifts of beam orbit have been really suppressed within 20μm without the compensation of BPM chamber motion in the runtime.

  12. Guidelines for determining design basis ground motions

    International Nuclear Information System (INIS)

    1993-11-01

    This report develops and applies a method for estimating strong earthquake ground motion. The emphasis of this study is on ground motion estimation in Eastern North America (east of the Rocky Mountains), with particular emphasis on the Eastern United States and southeastern Canada. Specifically considered are ground motions resulting from earthquakes with magnitudes from 5 to 8, fault distances from 0 to 500 km, and frequencies from 1 to 35 Hz. The two main objectives were: (1) to develop generic relations for estimating ground motion appropriate for site screening; and (2) to develop a guideline for conducting a thorough site investigation needed to define the seismic design basis. For the first objective, an engineering model was developed to predict the expected ground motion on rock sites, with an additional set of amplification factors to account for the response of the soil column over rock at soil sites. The results incorporate best estimates of ground motion as well as the randomness and uncertainty associated with those estimates. For the second objective, guidelines were developed for gathering geotechnical information at a site and using this information in calculating site response. As a part of this development, an extensive set of geotechnical and seismic investigations was conducted at three reference sites. Together, the engineering model and guidelines provide the means to select and assess the seismic suitability of a site

  13. The effects of the calcium-magnesium-bicarbonate content in thermal mineral water on chronic low back pain: a randomized, controlled follow-up study

    Science.gov (United States)

    Gáti, Tamás; Tefner, Ildikó Katalin; Kovács, Lajos; Hodosi, Katalin; Bender, Tamás

    2018-05-01

    The aim of this study was to investigate the effects of balneotherapy on chronic low back pain. This is a minimized, follow-up study evaluated according to the analysis of intention to treat. The subjects included in the study were 105 patients suffering from chronic low back pain. The control group ( n = 53) received the traditional musculoskeletal pain killer treatment, while the target group ( n = 52) attended thermal mineral water treatment for 3 weeks for 15 occasions on top of the usual musculoskeletal pain killer treatment. The following parameters were measured before, right after, and 9 weeks after the 3-week therapy: the level of low back pain in rest and the level during activity are tested using the Visual Analog Scale (VAS); specific questionnaire on the back pain (Oswestry); and a questionnaire on quality of life (EuroQual-5D). All of the investigated parameters improved significantly ( p low back pain.

  14. The effects of the calcium-magnesium-bicarbonate content in thermal mineral water on chronic low back pain: a randomized, controlled follow-up study

    Science.gov (United States)

    Tamás, Gáti; Katalin, Tefner Ildikó; Lajos, Kovács; Katalin, Hodosi; Tamás, Bender

    2018-01-01

    The aim of this study was to investigate the effects of balneotherapy on chronic low back pain. This is a minimized, follow-up study evaluated according to the analysis of intention to treat. The subjects included in the study were 105 patients suffering from chronic low back pain. The control group (n = 53) received the traditional musculoskeletal pain killer treatment, while the target group (n = 52) attended thermal mineral water treatment for 3 weeks for 15 occasions on top of the usual musculoskeletal pain killer treatment. The following parameters were measured before, right after, and 9 weeks after the 3-week therapy: the level of low back pain in rest and the level during activity are tested using the Visual Analog Scale (VAS); specific questionnaire on the back pain (Oswestry); and a questionnaire on quality of life (EuroQual-5D). All of the investigated parameters improved significantly (p chronic low back pain.

  15. Ground motion improvements in SPEAR3

    Energy Technology Data Exchange (ETDEWEB)

    Safranek, James A.; Yan, Yiton T.; Dell’Orco, Domenico; Gassner, Georg; Sunilkumar, Nikita

    2016-09-01

    SPEAR3 is a third-generation synchrotron light source storage ring, about 234 meters in circumference. To meet the beam stability requirement, our goal is to ultimately achieve an orbit variation (relative to the photon beam lines) of less than 10% of the beam size, which is about 1 micron in the vertical plane. Hydrostatic leveling system (HLS) measurements show that the height of the SPEAR3 tunnel floor can vary by tens of microns daily without thermal insulation improvements. We present an analysis of the HLS data that shows that adding thermal insulation to the concrete walls of the storage ring tunnel dramatically decreased diurnal tunnel floor motion.

  16. Wave propagation and scattering in random media

    CERN Document Server

    Ishimaru, Akira

    1978-01-01

    Wave Propagation and Scattering in Random Media, Volume 2, presents the fundamental formulations of wave propagation and scattering in random media in a unified and systematic manner. The topics covered in this book may be grouped into three categories: waves in random scatterers, waves in random continua, and rough surface scattering. Random scatterers are random distributions of many particles. Examples are rain, fog, smog, hail, ocean particles, red blood cells, polymers, and other particles in a state of Brownian motion. Random continua are the media whose characteristics vary randomly an

  17. Random walks, random fields, and disordered systems

    CERN Document Server

    Černý, Jiří; Kotecký, Roman

    2015-01-01

    Focusing on the mathematics that lies at the intersection of probability theory, statistical physics, combinatorics and computer science, this volume collects together lecture notes on recent developments in the area. The common ground of these subjects is perhaps best described by the three terms in the title: Random Walks, Random Fields and Disordered Systems. The specific topics covered include a study of Branching Brownian Motion from the perspective of disordered (spin-glass) systems, a detailed analysis of weakly self-avoiding random walks in four spatial dimensions via methods of field theory and the renormalization group, a study of phase transitions in disordered discrete structures using a rigorous version of the cavity method, a survey of recent work on interacting polymers in the ballisticity regime and, finally, a treatise on two-dimensional loop-soup models and their connection to conformally invariant systems and the Gaussian Free Field. The notes are aimed at early graduate students with a mod...

  18. CRDM motion analysis using machine learning technique

    International Nuclear Information System (INIS)

    Nishimura, Takuya; Nakayama, Hiroyuki; Saitoh, Mayumi; Yaguchi, Seiji

    2017-01-01

    Magnetic jack type Control Rod Drive Mechanism (CRDM) for pressurized water reactor (PWR) plant operates control rods in response to electrical signals from a reactor control system. CRDM operability is evaluated by quantifying armature's response of closed/opened time which means interval time between coil energizing/de-energizing points and armature closed/opened points. MHI has already developed an automatic CRDM motion analysis and applied it to actual plants so far. However, CRDM operational data has wide variation depending on their characteristics such as plant condition, plant, etc. In the existing motion analysis, there is an issue of analysis accuracy for applying a single analysis technique to all plant conditions, plants, etc. In this study, MHI investigated motion analysis using machine learning (Random Forests) which is flexibly accommodated to CRDM operational data with wide variation, and is improved analysis accuracy. (author)

  19. Thermal conductivity of nanofluids and size distribution of nanoparticles by Monte Carlo simulations

    International Nuclear Information System (INIS)

    Feng Yongjin; Yu Boming; Feng Kaiming; Xu Peng; Zou Mingqing

    2008-01-01

    Nanofluids, a class of solid-liquid suspensions, have received an increasing attention and studied intensively because of their anomalously high thermal conductivites at low nanoparticle concentration. Based on the fractal character of nanoparticles in nanofluids, the probability model for nanoparticle's sizes and the effective thermal conductivity model are derived, in which the effect of the microconvection due to the Brownian motion of nanoparticles in the fluids is taken into account. The proposed model is expressed as a function of the thermal conductivities of the base fluid and the nanoparticles, the volume fraction, fractal dimension for particles, the size of nanoparticles, and the temperature, as well as random number. This model has the characters of both analytical and numerical solutions. The Monte Carlo simulations combined with the fractal geometry theory are performed. The predictions by the present Monte Carlo simulations are shown in good accord with the existing experimental data.

  20. Toying with Motion.

    Science.gov (United States)

    Galus, Pamela J.

    2002-01-01

    Presents a variety of activities that support the development of an understanding of Newton's laws of motion. Activities use toy cars, mobile roads, and a seat-of-nails. Includes a scoring rubric. (DDR)

  1. Projectile Motion Hoop Challenge

    Science.gov (United States)

    Jordan, Connor; Dunn, Amy; Armstrong, Zachary; Adams, Wendy K.

    2018-04-01

    Projectile motion is a common phenomenon that is used in introductory physics courses to help students understand motion in two dimensions. Authors have shared a range of ideas for teaching this concept and the associated kinematics in The Physics Teacher; however, the "Hoop Challenge" is a new setup not before described in TPT. In this article an experiment is illustrated to explore projectile motion in a fun and challenging manner that has been used with both high school and university students. With a few simple materials, students have a vested interest in being able to calculate the height of the projectile at a given distance from its launch site. They also have an exciting visual demonstration of projectile motion when the lab is over.

  2. Travelers' Health: Motion Sickness

    Science.gov (United States)

    ... sickness, especially when pregnant, menstruating, or on hormones. Race/ethnicity—Asians may be more susceptible to motion ... it, sitting in the front seat of a car or bus, sitting over the wing of an ...

  3. Dizziness and Motion Sickness

    Science.gov (United States)

    ... that extends into the inner ear can completely destroy both the hearing and equilibrium function of that ... motion sickness: •Do not read while traveling •Avoid sitting in the rear seat •Do not sit in ...

  4. Motion Sickness: First Aid

    Science.gov (United States)

    ... com. Accessed July 29, 2017. Priesol AJ. Motion sickness. https://www.uptodate.com/content/search. Accessed July 29, 2017. Brunette GW, et al. CDC Health Information for International Travel 2018. New York, N. ...

  5. Coupled transverse motion

    International Nuclear Information System (INIS)

    Teng, L.C.

    1989-01-01

    The magnetic field in an accelerator or a storage ring is usually so designed that the horizontal (x) and the vertical (y) motions of an ion are uncoupled. However, because of imperfections in construction and alignment, some small coupling is unavoidable. In this lecture, we discuss in a general way what is known about the behaviors of coupled motions in two degrees-of-freedom. 11 refs., 6 figs

  6. Quasiperiodicity in time evolution of the Bloch vector under the thermal Jaynes-Cummings model

    Science.gov (United States)

    Azuma, Hiroo; Ban, Masashi

    2014-07-01

    We study a quasiperiodic structure in the time evolution of the Bloch vector, whose dynamics is governed by the thermal Jaynes-Cummings model (JCM). Putting the two-level atom into a certain pure state and the cavity field into a mixed state in thermal equilibrium at initial time, we let the whole system evolve according to the JCM Hamiltonian. During this time evolution, motion of the Bloch vector seems to be in disorder. Because of the thermal photon distribution, both a norm and a direction of the Bloch vector change hard at random. In this paper, taking a different viewpoint compared with ones that we have been used to, we investigate quasiperiodicity of the Bloch vector’s trajectories. Introducing the concept of the quasiperiodic motion, we can explain the confused behaviour of the system as an intermediate state between periodic and chaotic motions. More specifically, we discuss the following two facts: (1) If we adjust the time interval Δt properly, figures consisting of plotted dots at the constant time interval acquire scale invariance under replacement of Δt by sΔt, where s(>1) is an arbitrary real but not transcendental number. (2) We can compute values of the time variable t, which let |Sz(t)| (the absolute value of the z-component of the Bloch vector) be very small, with the Diophantine approximation (a rational approximation of an irrational number).

  7. The upper spatial limit for perception of displacement is affected by preceding motion.

    Science.gov (United States)

    Stefanova, Miroslava; Mateeff, Stefan; Hohnsbein, Joachim

    2009-03-01

    The upper spatial limit D(max) for perception of apparent motion of a random dot pattern may be strongly affected by another, collinear, motion that precedes it [Mateeff, S., Stefanova, M., &. Hohnsbein, J. (2007). Perceived global direction of a compound of real and apparent motion. Vision Research, 47, 1455-1463]. In the present study this phenomenon was studied with two-dimensional motion stimuli. A random dot pattern moved alternately in the vertical and oblique direction (zig-zag motion). The vertical motion was of 1.04 degrees length; it was produced by three discrete spatial steps of the dots. Thereafter the dots were displaced by a single spatial step in oblique direction. Each motion lasted for 57ms. The upper spatial limit for perception of the oblique motion was measured under two conditions: the vertical component of the oblique motion and the vertical motion were either in the same or in opposite directions. It was found that the perception of the oblique motion was strongly influenced by the relative direction of the vertical motion that preceded it; in the "same" condition the upper spatial limit was much shorter than in the "opposite" condition. Decreasing the speed of the vertical motion reversed this effect. Interpretations based on networks of motion detectors and on Gestalt theory are discussed.

  8. Time-averaged MSD of Brownian motion

    OpenAIRE

    Andreanov, Alexei; Grebenkov, Denis

    2012-01-01

    We study the statistical properties of the time-averaged mean-square displacements (TAMSD). This is a standard non-local quadratic functional for inferring the diffusion coefficient from an individual random trajectory of a diffusing tracer in single-particle tracking experiments. For Brownian motion, we derive an exact formula for the Laplace transform of the probability density of the TAMSD by mapping the original problem onto chains of coupled harmonic oscillators. From this formula, we de...

  9. Depinning of interacting particles in random media

    Science.gov (United States)

    Zapperi, Stefano; Andrade, José S., Jr.; Mendes Filho, Josué

    2000-06-01

    We study the overdamped motion of interacting particles in a random medium using the model introduced by Pla and Nori [Phys. Rev. Lett. 67, 919 (1991)]. We investigate the associated depinning transition by numerical integration of the equation of motion and show evidence that the model is in the same universality class of a driven elastic chain on a rough substrate. We discuss the implications of these results for flux line motion in type-II superconductors.

  10. Randomization tests

    CERN Document Server

    Edgington, Eugene

    2007-01-01

    Statistical Tests That Do Not Require Random Sampling Randomization Tests Numerical Examples Randomization Tests and Nonrandom Samples The Prevalence of Nonrandom Samples in Experiments The Irrelevance of Random Samples for the Typical Experiment Generalizing from Nonrandom Samples Intelligibility Respect for the Validity of Randomization Tests Versatility Practicality Precursors of Randomization Tests Other Applications of Permutation Tests Questions and Exercises Notes References Randomized Experiments Unique Benefits of Experiments Experimentation without Mani

  11. Theoretical Exploration of Exponential Heat Source and Thermal Stratification Effects on The Motion of 3-Dimensional Flow of Casson Fluid Over a Low Heat Energy Surface at Initial Unsteady Stage

    Science.gov (United States)

    Sandeep, N.; Animasaun, I. L.

    2017-06-01

    Within the last few decades, experts and scientists dealing with the flow of non-Newtonian fluids (most especially Casson fluid) have confirmed the existence of such flow on a stretchable surface with low heat energy (i.e. absolute zero of temperature). This article presents the motion of a three-dimensional of such fluid. Influence of uniform space dependent internal heat source on the intermolecular forces holding the molecules of Casson fluid is investigated. It is assumed that the stagnation flow was induced by an external force (pressure gradient) together with impulsive. Based on these assumptions, variable thermophysical properties are most suitable; hence modified kinematic viscosity model is presented. The system of governing equations of 3-dimensional unsteady Casson fluid was non-dimensionalized using suitable similarity transformation which unravels the behavior of the flow at full fledge short period. The numerical solution of the corresponding boundary value problem (ODE) was obtained using Runge-Kutta fourth order along with shooting technique. The intermolecular forces holding the molecules of Casson fluid flow in both horizontal directions when magnitude of velocity ratio parameters are greater than unity breaks continuously with an increase in Casson parameter and this leads to an increase in velocity profiles in both directions.

  12. Theoretical Exploration of Exponential Heat Source and Thermal Stratification Effects on The Motion of 3-Dimensional Flow of Casson Fluid Over a Low Heat Energy Surface at Initial Unsteady Stage

    Directory of Open Access Journals (Sweden)

    Sandeep N.

    2017-06-01

    Full Text Available Within the last few decades, experts and scientists dealing with the flow of non-Newtonian fluids (most especially Casson fluid have confirmed the existence of such flow on a stretchable surface with low heat energy (i.e. absolute zero of temperature. This article presents the motion of a three-dimensional of such fluid. Influence of uniform space dependent internal heat source on the intermolecular forces holding the molecules of Casson fluid is investigated. It is assumed that the stagnation flow was induced by an external force (pressure gradient together with impulsive. Based on these assumptions, variable thermophysical properties are most suitable; hence modified kinematic viscosity model is presented. The system of governing equations of 3-dimensional unsteady Casson fluid was non-dimensionalized using suitable similarity transformation which unravels the behavior of the flow at full fledge short period. The numerical solution of the corresponding boundary value problem (ODE was obtained using Runge-Kutta fourth order along with shooting technique. The intermolecular forces holding the molecules of Casson fluid flow in both horizontal directions when magnitude of velocity ratio parameters are greater than unity breaks continuously with an increase in Casson parameter and this leads to an increase in velocity profiles in both directions.

  13. Exit from Synchrony in Joint Improvised Motion.

    Directory of Open Access Journals (Sweden)

    Assi Dahan

    Full Text Available Motion synchrony correlates with effective and well-rated human interaction. However, people do not remain locked in synchrony; Instead, they repeatedly enter and exit synchrony. In many important interactions, such as therapy, marriage and parent-infant communication, it is the ability to exit and then re-enter synchrony that is thought to build strong relationship. The phenomenon of entry into zero-phase synchrony is well-studied experimentally and in terms of mathematical modeling. In contrast, exit-from-synchrony is under-studied. Here, we focus on human motion coordination, and examine the exit-from-synchrony phenomenon using experimental data from the mirror game paradigm, in which people perform joint improvised motion, and from human tracking of computer-generated stimuli. We present a mathematical mechanism that captures aspects of exit-from-synchrony in human motion. The mechanism adds a random motion component when the accumulated velocity error between the players is small. We introduce this mechanism to several models for human coordinated motion, including the widely studied HKB model, and the predictor-corrector model of Noy, Dekel and Alon. In all models, the new mechanism produces realistic simulated behavior when compared to experimental data from the mirror game and from tracking of computer generated stimuli, including repeated entry and exit from zero-phase synchrony that generates a complexity of motion similar to that of human players. We hope that these results can inform future research on exit-from-synchrony, to better understand the dynamics of coordinated action of people and to enhance human-computer and human-robot interaction.

  14. THERMAL: A routine designed to calculate neutron thermal scattering

    International Nuclear Information System (INIS)

    Cullen, D.E.

    1995-01-01

    THERMAL is designed to calculate neutron thermal scattering that is isotropic in the center of mass system. At low energy thermal motion will be included. At high energies the target nuclei are assumed to be stationary. The point of transition between low and high energies has been defined to insure a smooth transition. It is assumed that at low energy the elastic cross section is constant in the center of mass system. At high energy the cross section can be of any form. You can use this routine for all energies where the elastic scattering is isotropic in the center of mass system. In most materials this will be a fairly high energy

  15. Thermal stress relaxation in magnesium composites during thermal cycling

    Energy Technology Data Exchange (ETDEWEB)

    Trojanova, Z.; Lukac, P. (Karlova Univ., Prague (Czech Republic)); Kiehn, J.; Kainer, K.U.; Mordike, B.L. (Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany))

    1998-01-01

    It has been shown that the internal friction of Mg - Saffil metal matrix composites can be influenced by thermal stresses, if MMCc are submitted to thermal cycling between room temperature and an upper temperature of cycling. These stresses can be accommodated by generation and motion of dislocations giving the formation of the microplastic zones. The thermal stress relaxation depends on the upper temperature of cycling, the volume fraction of reinforcement and the matrix composition and can result in plastic deformation and strain hardening of the matrix without applied stress. The internal friction measurements can be used for non destructive investigation of processes which influence the mechanical properties. (orig.)

  16. Design of the muscles in motion study: a randomized controlled trial to evaluate the efficacy and feasibility of an individually tailored home-based exercise training program for children and adolescents with juvenile dermatomyositis

    Directory of Open Access Journals (Sweden)

    Habers Esther A

    2012-06-01

    Full Text Available Abstract Background Juvenile dermatomyositis (JDM is a rare, often chronic, systemic autoimmune disease of childhood, characterized by inflammation of the microvasculature of the skeletal muscle and skin. Prominent clinical features include significant exercise intolerance, muscle weakness, and fatigue. Despite pharmacological improvements, these clinical features continue to affect patients with JDM, even when the disease is in remission. Exercise training is increasingly utilized as a non-pharmacological intervention in the clinical management of (adult patients with chronic inflammatory conditions; however no randomized controlled trials (RCT have been performed in JDM. In the current study, the efficacy and feasibility of an exercise training program in patients with JDM will be examined. Methods/design Subjects (n = 30 will include 8–18 year olds diagnosed with JDM. The intervention consists of an individually tailored 12-weeks home-based exercise training program in which interval training on a treadmill is alternated with strength training during each session. The program is based on previous literature and designed with a defined frequency, intensity, time, and type of exercise (FITT principles. Primary outcome measures include aerobic exercise capacity, isometric muscle strength, and perception of fatigue. The study methodology has been conceived according to the standards of the CONSORT guidelines. The current study will be a multi-center (4 Dutch University Medical Centers RCT, with the control group also entering the training arm directly after completion of the initial protocol. Randomization is stratified according to age and gender. Discussion The current study will provide evidence on the efficacy and feasibility of an individually tailored 12-week home-based exercise training program in youth with JDM. Trial registration Medical Ethics Committee of the University Medical Center Utrecht, the Netherlands: 11–336

  17. Ground motion predictions

    Energy Technology Data Exchange (ETDEWEB)

    Loux, P C [Environmental Research Corporation, Alexandria, VA (United States)

    1969-07-01

    Nuclear generated ground motion is defined and then related to the physical parameters that cause it. Techniques employed for prediction of ground motion peak amplitude, frequency spectra and response spectra are explored, with initial emphasis on the analysis of data collected at the Nevada Test Site (NTS). NTS postshot measurements are compared with pre-shot predictions. Applicability of these techniques to new areas, for example, Plowshare sites, must be questioned. Fortunately, the Atomic Energy Commission is sponsoring complementary studies to improve prediction capabilities primarily in new locations outside the NTS region. Some of these are discussed in the light of anomalous seismic behavior, and comparisons are given showing theoretical versus experimental results. In conclusion, current ground motion prediction techniques are applied to events off the NTS. Predictions are compared with measurements for the event Faultless and for the Plowshare events, Gasbuggy, Cabriolet, and Buggy I. (author)

  18. Method through motion

    DEFF Research Database (Denmark)

    Steijn, Arthur

    2016-01-01

    Contemporary scenography often consists of video-projected motion graphics. The field is lacking in academic methods and rigour: descriptions and models relevant for the creation as well as in the analysis of existing works. In order to understand the phenomenon of motion graphics in a scenographic...... construction as a support to working systematically practice-led research project. The design model is being developed through design laboratories and workshops with students and professionals who provide feedback that lead to incremental improvements. Working with this model construction-as-method reveals...... context, I have been conducting a practice-led research project. Central to the project is construction of a design model describing sets of procedures, concepts and terminology relevant for design and studies of motion graphics in spatial contexts. The focus of this paper is the role of model...

  19. Ground motion predictions

    International Nuclear Information System (INIS)

    Loux, P.C.

    1969-01-01

    Nuclear generated ground motion is defined and then related to the physical parameters that cause it. Techniques employed for prediction of ground motion peak amplitude, frequency spectra and response spectra are explored, with initial emphasis on the analysis of data collected at the Nevada Test Site (NTS). NTS postshot measurements are compared with pre-shot predictions. Applicability of these techniques to new areas, for example, Plowshare sites, must be questioned. Fortunately, the Atomic Energy Commission is sponsoring complementary studies to improve prediction capabilities primarily in new locations outside the NTS region. Some of these are discussed in the light of anomalous seismic behavior, and comparisons are given showing theoretical versus experimental results. In conclusion, current ground motion prediction techniques are applied to events off the NTS. Predictions are compared with measurements for the event Faultless and for the Plowshare events, Gasbuggy, Cabriolet, and Buggy I. (author)

  20. Langevin theory of anomalous Brownian motion made simple

    International Nuclear Information System (INIS)

    Tothova, Jana; Vasziova, Gabriela; Lisy, VladimIr; Glod, Lukas

    2011-01-01

    During the century from the publication of the work by Einstein (1905 Ann. Phys. 17 549) Brownian motion has become an important paradigm in many fields of modern science. An essential impulse for the development of Brownian motion theory was given by the work of Langevin (1908 C. R. Acad. Sci., Paris 146 530), in which he proposed an 'infinitely more simple' description of Brownian motion than that by Einstein. The original Langevin approach has however strong limitations, which were rigorously stated after the creation of the hydrodynamic theory of Brownian motion (1945). Hydrodynamic Brownian motion is a special case of 'anomalous Brownian motion', now intensively studied both theoretically and in experiments. We show how some general properties of anomalous Brownian motion can be easily derived using an effective method that allows one to convert the stochastic generalized Langevin equation into a deterministic Volterra-type integro-differential equation for the mean square displacement of the particle. Within the Gibbs statistics, the method is applicable to linear equations of motion with any kind of memory during the evolution of the system. We apply it to memoryless Brownian motion in a harmonic potential well and to Brownian motion in fluids, taking into account the effects of hydrodynamic memory. Exploring the mathematical analogy between Brownian motion and electric circuits, which are at nanoscales also described by the generalized Langevin equation, we calculate the fluctuations of charge and current in RLC circuits that are in contact with the thermal bath. Due to the simplicity of our approach it could be incorporated into graduate courses of statistical physics. Once the method is established, it allows bringing to the attention of students and effectively solving a number of attractive problems related to Brownian motion.

  1. Bell inequalities for random fields

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, Peter [Physics Department, Yale University, CT 06520 (United States)

    2006-06-09

    The assumptions required for the derivation of Bell inequalities are not satisfied for random field models in which there are any thermal or quantum fluctuations, in contrast to the general satisfaction of the assumptions for classical two point particle models. Classical random field models that explicitly include the effects of quantum fluctuations on measurement are possible for experiments that violate Bell inequalities.

  2. Bell inequalities for random fields

    OpenAIRE

    Morgan, Peter

    2004-01-01

    The assumptions required for the derivation of Bell inequalities are not usually satisfied for random fields in which there are any thermal or quantum fluctuations, in contrast to the general satisfaction of the assumptions for classical two point particle models. Classical random field models that explicitly include the effects of quantum fluctuations on measurement are possible for experiments that violate Bell inequalities.

  3. Leap Motion development essentials

    CERN Document Server

    Spiegelmock, Mischa

    2013-01-01

    This book is a fast-paced guide with practical examples that aims to help you understand and master the Leap Motion SDK.This book is for developers who are either involved in game development or who are looking to utilize Leap Motion technology in order to create brand new user interaction experiences to distinguish their products from the mass market. You should be comfortable with high-level languages and object-oriented development concepts in order to get the most out of this book.

  4. Generating random numbers by means of nonlinear dynamic systems

    Science.gov (United States)

    Zang, Jiaqi; Hu, Haojie; Zhong, Juhua; Luo, Duanbin; Fang, Yi

    2018-07-01

    To introduce the randomness of a physical process to students, a chaotic pendulum experiment was opened in East China University of Science and Technology (ECUST) on the undergraduate level in the physics department. It was shown chaotic motion could be initiated through adjusting the operation of a chaotic pendulum. By using the data of the angular displacements of chaotic motion, random binary numerical arrays can be generated. To check the randomness of generated numerical arrays, the NIST Special Publication 800-20 method was adopted. As a result, it was found that all the random arrays which were generated by the chaotic motion could pass the validity criteria and some of them were even better than the quality of pseudo-random numbers generated by a computer. Through the experiments, it is demonstrated that chaotic pendulum can be used as an efficient mechanical facility in generating random numbers, and can be applied in teaching random motion to the students.

  5. Design of the Quality of Life in Motion (QLIM) study: a randomized controlled trial to evaluate the effectiveness and cost-effectiveness of a combined physical exercise and psychosocial training program to improve physical fitness in children with cancer

    International Nuclear Information System (INIS)

    Braam, Katja I; Huisman, Jaap; Kaspers, Gertjan JL; Dulmen-den Broeder, Eline van; Dijk, Elisabeth M van; Veening, Margreet A; Bierings, Marc B; Merks, Johannes HM; Grootenhuis, Martha A; Chinapaw, Mai JM; Sinnema, Gerben; Takken, Tim

    2010-01-01

    Childhood cancer and its treatment have considerable impact on a child's physical and mental wellbeing. Especially long-term administration of chemotherapy and/or radiotherapy impairs physical fitness both during and after therapy, when children often present with muscle weakness and/or low cardiorespiratory fitness. Physical exercise can improve these two elements of physical fitness, but the positive effects of physical exercise might be further increased when a child's wellbeing is simultaneously enhanced by psychosocial training. Feeling better may increase the willingness and motivation to engage in sports activities. Therefore, this multi-centre study evaluates the short and long-term changes in physical fitness of a child with a childhood malignancy, using a combined physical exercise and psychosocial intervention program, implemented during or shortly after treatment. Also examined is whether positive effects on physical fitness reduce inactivity-related adverse health problems, improve quality of life, and are cost-effective. This multi-centre randomized controlled trial compares a combined physical and psychosocial intervention program for children with cancer, with care as usual (controls). Children with cancer (aged 8-18 years) treated with chemotherapy and/or radiotherapy, and who are no longer than 1 year post-treatment, are eligible for participation. A total of 100 children are being recruited from the paediatric oncology/haematology departments of three Dutch university medical centres. Patients are stratified according to pubertal stage (girls: age ≤10 or >10 years; boys: ≤11 or >11 years), type of malignancy (haematological or solid tumour), and moment of inclusion into the study (during or after treatment), and are randomly assigned to the intervention or control group. Childhood cancer patients undergoing long-term cancer therapy may benefit from a combined physical exercise and psychosocial intervention program since it may

  6. Design of the Quality of Life in Motion (QLIM study: a randomized controlled trial to evaluate the effectiveness and cost-effectiveness of a combined physical exercise and psychosocial training program to improve physical fitness in children with cancer

    Directory of Open Access Journals (Sweden)

    Takken Tim

    2010-11-01

    Full Text Available Abstract Background Childhood cancer and its treatment have considerable impact on a child's physical and mental wellbeing. Especially long-term administration of chemotherapy and/or radiotherapy impairs physical fitness both during and after therapy, when children often present with muscle weakness and/or low cardiorespiratory fitness. Physical exercise can improve these two elements of physical fitness, but the positive effects of physical exercise might be further increased when a child's wellbeing is simultaneously enhanced by psychosocial training. Feeling better may increase the willingness and motivation to engage in sports activities. Therefore, this multi-centre study evaluates the short and long-term changes in physical fitness of a child with a childhood malignancy, using a combined physical exercise and psychosocial intervention program, implemented during or shortly after treatment. Also examined is whether positive effects on physical fitness reduce inactivity-related adverse health problems, improve quality of life, and are cost-effective. Methods This multi-centre randomized controlled trial compares a combined physical and psychosocial intervention program for children with cancer, with care as usual (controls. Children with cancer (aged 8-18 years treated with chemotherapy and/or radiotherapy, and who are no longer than 1 year post-treatment, are eligible for participation. A total of 100 children are being recruited from the paediatric oncology/haematology departments of three Dutch university medical centres. Patients are stratified according to pubertal stage (girls: age ≤10 or >10 years; boys: ≤11 or >11 years, type of malignancy (haematological or solid tumour, and moment of inclusion into the study (during or after treatment, and are randomly assigned to the intervention or control group. Discussion Childhood cancer patients undergoing long-term cancer therapy may benefit from a combined physical exercise and

  7. Wiimote Experiments: Circular Motion

    Science.gov (United States)

    Kouh, Minjoon; Holz, Danielle; Kawam, Alae; Lamont, Mary

    2013-01-01

    The advent of new sensor technologies can provide new ways of exploring fundamental physics. In this paper, we show how a Wiimote, which is a handheld remote controller for the Nintendo Wii video game system with an accelerometer, can be used to study the dynamics of circular motion with a very simple setup such as an old record player or a…

  8. Ship Roll Motion Control

    DEFF Research Database (Denmark)

    Perez, Tristan; Blanke, Mogens

    2010-01-01

    . This tutorial paper presents an account of the development of various ship roll motion control systems and the challenges associated with their design. The paper discusses how to assess performance, the applicability of dierent models, and control methods that have been applied in the past....

  9. Motion of magnetotactic microorganisms

    International Nuclear Information System (INIS)

    Esquivel, D.M.S.; Barros, H.G. de P.L. de.

    1985-01-01

    Magnetic moments for different magnetotactic microorganisms are obtained by electron microscopy analyses and studies of motion by optical microscopy. The results are analysed in terms of a model due to C.Bean. The considerations presented suggest that magnetotaxy is an efficient mechanism for orientation only if the time for reorientation is smaller than the cycles of environmental perturbations. (Author) [pt

  10. Stochastic Blind Motion Deblurring

    KAUST Repository

    Xiao, Lei; Gregson, James; Heide, Felix; Heidrich, Wolfgang

    2015-01-01

    Blind motion deblurring from a single image is a highly under-constrained problem with many degenerate solutions. A good approximation of the intrinsic image can therefore only be obtained with the help of prior information in the form of (often non

  11. Markerless Motion Tracking

    DEFF Research Database (Denmark)

    Brooks, Anthony Lewis; Czarowicz, Alex

    2012-01-01

    This contribution focuses on the Associated Technologies aspect of the ICDVRAT event. Two industry leading markerless motion capture systems are examined that offer advancement in the field of rehabilitation. Residing at each end of the cost continuum, technical differences such as 3D versus 360 ...

  12. Motion sensing energy controller

    International Nuclear Information System (INIS)

    Saphir, M.E.; Reed, M.A.

    1984-01-01

    A moving object sensing processor responsive to slowly varying motions of a human being or other moving object in a zone of interest employs high frequency pulse modulated non-visible radiation generated by a radiation generating source, such as an LED, and detected by a detector sensitive to radiation of a preselected wavelength which generates electrical signals representative of the reflected radiation received from the zone of interest. The detectorsignals are processed to normalize the base level and remove variations due to background level changes, and slowly varying changes in the signals are detected by a bi-polar threshold detector. The control signals generated by the threshold detector in response to slowly varying motion are used to control the application of power to a utilization device, such as a set of fluoroescent lights in a room, the power being applied in response to detection of such motion and being automatically terminated in the absence of such motion after a predetermined time period established by a settable incrementable counter

  13. Algebraic Description of Motion

    Science.gov (United States)

    Davidon, William C.

    1974-01-01

    An algebraic definition of time differentiation is presented and used to relate independent measurements of position and velocity. With this, students can grasp certain essential physical, geometric, and algebraic properties of motion and differentiation before undertaking the study of limits. (Author)

  14. Rotational motion in nuclei

    International Nuclear Information System (INIS)

    Bohr, A.

    1977-01-01

    History is surveyed of the development of the theory of rotational states in nuclei. The situation in the 40's when ideas formed of the collective states of a nucleus is evoked. The general rotation theory and the relation between the single-particle and rotational motion are briefly discussed. Future prospects of the rotation theory development are indicated. (I.W.)

  15. Motion Control with Vision

    NARCIS (Netherlands)

    Ir. Dick van Schenk Brill; Ir Peter Boots

    2001-01-01

    This paper describes the work that is done by a group of I3 students at Philips CFT in Eindhoven, Netherlands. I3 is an initiative of Fontys University of Professional Education also located in Eindhoven. The work focuses on the use of computer vision in motion control. Experiments are done with

  16. Superluminal motion (review)

    Science.gov (United States)

    Malykin, G. B.; Romanets, E. A.

    2012-06-01

    Prior to the development of Special Relativity, no restrictions were imposed on the velocity of the motion of particles and material bodies, as well as on energy transfer and signal propagation. At the end of the 19th century and the beginning of the 20th century, it was shown that a charge that moves at a velocity faster than the speed of light in an optical medium, in particular, in vacuum, gives rise to impact radiation, which later was termed the Vavilov-Cherenkov radiation. Shortly after the development of Special Relativity, some researchers considered the possibility of superluminal motion. In 1923, the Soviet physicist L.Ya. Strum suggested the existence of tachyons, which, however, have not been discovered yet. Superluminal motions can occur only for images, e.g., for so-called "light spots," which were considered in 1972 by V.L. Ginzburg and B.M. Bolotovskii. These spots can move with a superluminal phase velocity but are incapable of transferring energy and information. Nevertheless, these light spots may induce quite real generation of microwave radiation in closed waveguides and create the Vavilov-Cherenkov radiation in vacuum. In this work, we consider various paradoxes, illusions, and artifacts associated with superluminal motion.

  17. A Harmonic Motion Experiment

    Science.gov (United States)

    Gluck, P.; Krakower, Zeev

    2010-01-01

    We present a unit comprising theory, simulation and experiment for a body oscillating on a vertical spring, in which the simultaneous use of a force probe and an ultrasonic range finder enables one to explore quantitatively and understand many aspects of simple and damped harmonic motions. (Contains 14 figures.)

  18. Choosing a Motion Detector.

    Science.gov (United States)

    Ballard, David M.

    1990-01-01

    Examines the characteristics of three types of motion detectors: Doppler radar, infrared, and ultrasonic wave, and how they are used on school buses to prevent students from being killed by their own school bus. Other safety devices cited are bus crossing arms and a camera monitor system. (MLF)

  19. S4-3: Spatial Processing of Visual Motion

    Directory of Open Access Journals (Sweden)

    Shin'ya Nishida

    2012-10-01

    Full Text Available Local motion signals are extracted in parallel by a bank of motion detectors, and their spatiotemporal interactions are processed in subsequent stages. In this talk, I will review our recent studies on spatial interactions in visual motion processing. First, we found two types of spatial pooling of local motion signals. Directionally ambiguous 1D local motion signals are pooled across orientation and space for solution of the aperture problem, while 2D local motion signals are pooled for estimation of global vector average (e.g., Amano et al., 2009 Journal of Vision 9(3:4 1–25. Second, when stimulus presentation is brief, coherent motion detection of dynamic random-dot kinematogram is not efficient. Nevertheless, it is significantly improved by transient and synchronous presentation of a stationary surround pattern. This suggests that centre-surround spatial interaction may help rapid perception of motion (Linares et al., submitted. Third, to know how the visual system encodes pairwise relationships between remote motion signals, we measured the temporal rate limit for perceiving the relationship of two motion directions presented at the same time at different spatial locations. Compared with similar tasks with luminance or orientation signals, motion comparison was more rapid and hence efficient. This high performance was affected little by inter-element separation even when it was increased up to 100 deg. These findings indicate the existence of specialized processes to encode long-range relationships between motion signals for quick appreciation of global dynamic scene structure (Maruya et al., in preparation.

  20. Fractional Brownian motion and long term clinical trial recruitment.

    Science.gov (United States)

    Zhang, Qiang; Lai, Dejian

    2011-05-01

    Prediction of recruitment in clinical trials has been a challenging task. Many methods have been studied, including models based on Poisson process and its large sample approximation by Brownian motion (BM), however, when the independent incremental structure is violated for BM model, we could use fractional Brownian motion to model and approximate the underlying Poisson processes with random rates. In this paper, fractional Brownian motion (FBM) is considered for such conditions and compared to BM model with illustrated examples from different trials and simulations.

  1. Speed and accuracy of visual motion discrimination by rats.

    Directory of Open Access Journals (Sweden)

    Pamela Reinagel

    Full Text Available Animals must continuously evaluate sensory information to select the preferable among possible actions in a given context, including the option to wait for more information before committing to another course of action. In experimental sensory decision tasks that replicate these features, reaction time distributions can be informative about the implicit rules by which animals determine when to commit and what to do. We measured reaction times of Long-Evans rats discriminating the direction of motion in a coherent random dot motion stimulus, using a self-paced two-alternative forced-choice (2-AFC reaction time task. Our main findings are: (1 When motion strength was constant across trials, the error trials had shorter reaction times than correct trials; in other words, accuracy increased with response latency. (2 When motion strength was varied in randomly interleaved trials, accuracy increased with motion strength, whereas reaction time decreased. (3 Accuracy increased with reaction time for each motion strength considered separately, and in the interleaved motion strength experiment overall. (4 When stimulus duration was limited, accuracy improved with stimulus duration, whereas reaction time decreased. (5 Accuracy decreased with response latency after stimulus offset. This was the case for each stimulus duration considered separately, and in the interleaved duration experiment overall. We conclude that rats integrate visual evidence over time, but in this task the time of their response is governed more by elapsed time than by a criterion for sufficient evidence.

  2. ORTEP-III: Oak Ridge Thermal Ellipsoid Plot Program for crystal structure illustrations

    Energy Technology Data Exchange (ETDEWEB)

    Burnett, M.N.; Johnson, C.K.

    1996-07-01

    This report describes a computer program for drawing crystal structure illustrations. Ball-and-stick type illustrations of a quality suitable for publication are produced with either spheres or thermal-motion probability ellipsoids on the atomic sites. The program can also produce stereoscopic pairs of illustrations which aid in the visualization of complex packing arrangements of atoms and thermal motion patterns. Interatomic distances, bond angles, and principal axes of thermal motion are also calculated to aid the structural study.

  3. PET motion correction using PRESTO with ITK motion estimation

    Energy Technology Data Exchange (ETDEWEB)

    Botelho, Melissa [Institute of Biophysics and Biomedical Engineering, Science Faculty of University of Lisbon (Portugal); Caldeira, Liliana; Scheins, Juergen [Institute of Neuroscience and Medicine (INM-4), Forschungszentrum Jülich (Germany); Matela, Nuno [Institute of Biophysics and Biomedical Engineering, Science Faculty of University of Lisbon (Portugal); Kops, Elena Rota; Shah, N Jon [Institute of Neuroscience and Medicine (INM-4), Forschungszentrum Jülich (Germany)

    2014-07-29

    The Siemens BrainPET scanner is a hybrid MRI/PET system. PET images are prone to motion artefacts which degrade the image quality. Therefore, motion correction is essential. The library PRESTO converts motion-corrected LORs into highly accurate generic projection data [1], providing high-resolution PET images. ITK is an open-source software used for registering multidimensional data []. ITK provides motion estimation necessary to PRESTO.

  4. PET motion correction using PRESTO with ITK motion estimation

    International Nuclear Information System (INIS)

    Botelho, Melissa; Caldeira, Liliana; Scheins, Juergen; Matela, Nuno; Kops, Elena Rota; Shah, N Jon

    2014-01-01

    The Siemens BrainPET scanner is a hybrid MRI/PET system. PET images are prone to motion artefacts which degrade the image quality. Therefore, motion correction is essential. The library PRESTO converts motion-corrected LORs into highly accurate generic projection data [1], providing high-resolution PET images. ITK is an open-source software used for registering multidimensional data []. ITK provides motion estimation necessary to PRESTO.

  5. A multiscale guide to Brownian motion

    International Nuclear Information System (INIS)

    Grebenkov, Denis S; Belyaev, Dmitry; Jones, Peter W

    2016-01-01

    We revise the Lévy construction of Brownian motion as a simple though rigorous approach to operate with various Gaussian processes. A Brownian path is explicitly constructed as a linear combination of wavelet-based ‘geometrical features’ at multiple length scales with random weights. Such a wavelet representation gives a closed formula mapping of the unit interval onto the functional space of Brownian paths. This formula elucidates many classical results about Brownian motion (e.g., non-differentiability of its path), providing an intuitive feeling for non-mathematicians. The illustrative character of the wavelet representation, along with the simple structure of the underlying probability space, is different from the usual presentation of most classical textbooks. Similar concepts are discussed for the Brownian bridge, fractional Brownian motion, the Ornstein-Uhlenbeck process, Gaussian free fields, and fractional Gaussian fields. Wavelet representations and dyadic decompositions form the basis of many highly efficient numerical methods to simulate Gaussian processes and fields, including Brownian motion and other diffusive processes in confining domains. (topical review)

  6. Thermal comfort

    CSIR Research Space (South Africa)

    Osburn, L

    2010-01-01

    Full Text Available Thermal comfort is influenced by environmental parameters as well as other influences including asymmetric heating and cooling conditions. Additionally, some aspects of thermal comfort may be exploited so as to enable a building to operate within a...

  7. Contribution of thermal expansion and

    Directory of Open Access Journals (Sweden)

    O.I.Pursky

    2007-01-01

    Full Text Available A theoretical model is developed to describe the experimental results obtained for the isobaric thermal conductivity of rare gas solids (RGS. The isobaric thermal conductivity of RGS has been analysed within Debye approximation with regard to the effect of thermal expansion. The suggested model takes into consideration the fact that thermal conductivity is determined by U-processes while above the phonon mobility edge it is determined by "diffusive" modes migrating randomly from site to site. The mobility edge ω0 is determined from the condition that the phonon mean-free path restricted by the U-processes cannot be smaller than half of the phonon wavelength.

  8. Precision of working memory for visual motion sequences and transparent motion surfaces.

    Science.gov (United States)

    Zokaei, Nahid; Gorgoraptis, Nikos; Bahrami, Bahador; Bays, Paul M; Husain, Masud

    2011-12-01

    Recent studies investigating working memory for location, color, and orientation support a dynamic resource model. We examined whether this might also apply to motion, using random dot kinematograms (RDKs) presented sequentially or simultaneously. Mean precision for motion direction declined as sequence length increased, with precision being lower for earlier RDKs. Two alternative models of working memory were compared specifically to distinguish between the contributions of different sources of error that corrupt memory (W. Zhang & S. J. Luck, 2008 vs. P. M. Bays, R. F. G. Catalao, & M. Husain, 2009). The latter provided a significantly better fit for the data, revealing that decrease in memory precision for earlier items is explained by an increase in interference from other items in a sequence rather than random guessing or a temporal decay of information. Misbinding feature attributes is an important source of error in working memory. Precision of memory for motion direction decreased when two RDKs were presented simultaneously as transparent surfaces, compared to sequential RDKs. However, precision was enhanced when one motion surface was prioritized, demonstrating that selective attention can improve recall precision. These results are consistent with a resource model that can be used as a general conceptual framework for understanding working memory across a range of visual features.

  9. Spatial design and control of graphene flake motion

    Science.gov (United States)

    Ghorbanfekr-Kalashami, H.; Peeters, F. M.; Novoselov, K. S.; Neek-Amal, M.

    2017-08-01

    The force between a sharp scanning probe tip and a surface can drive a graphene flake over crystalline substrates. The recent design of particular patterns of structural defects on a graphene surface allows us to propose an alternative approach for controlling the motion of a graphene flake over a graphene substrate. The thermally induced motion of a graphene flake is controlled by engineering topological defects in the substrate. Such defect regions lead to an inhomogeneous energy landscape and are energetically unfavorable for the motion of the flake, and will invert and scatter graphene flakes when they are moving toward the defect line. Engineering the distribution of these energy barriers results in a controllable trajectory for the thermal motion of the flake without using any external force. We predict superlubricity of the graphene flake for motion along and between particular defect lines. This Rapid Communication provides insights into the frictional forces of interfaces and opens a route to the engineering of the stochastic motion of a graphene flake over any crystalline substrate.

  10. Low level cloud motion vectors from Kalpana-1 visible images

    Indian Academy of Sciences (India)

    . In this paper, an attempt has been made to retrieve low-level cloud motion vectors using Kalpana-1 visible (VIS) images at every half an hour. The VIS channel provides better detection of low level clouds, which remain obscure in thermal IR ...

  11. Thermophoretic Motion of Water Nanodroplets confined inside Carbon Nanotubes

    DEFF Research Database (Denmark)

    Zambrano, Harvey A; Walther, Jens Honore; Koumoutsakos, Petros

    2009-01-01

    We study the thermophoretic motion of water nanodroplets confined inside carbon nanotubes using molecular dynamics simulations. We find that the nanodroplets move in the direction opposite the imposed thermal gradient with a terminal velocity that is linearly proportional to the gradient....... The translational motion is associated with a solid body rotation of the water nanodroplet coinciding with the helical symmetry of the carbon nanotube. The thermal diffusion displays a weak dependence on the wetting of the water-carbon nanotube interface. We introduce the use of the Moment Scaling Spectrum (MSS......) in order to determine the characteristics of the motion of the nanoparticles inside the carbon nanotube. The MSS indicates that affinity of the nanodroplet with the walls of the carbon nanotubes is important for the isothermal diffusion, and hence for the Soret coefficient of the system....

  12. Random walk on random walks

    NARCIS (Netherlands)

    Hilário, M.; Hollander, den W.Th.F.; Sidoravicius, V.; Soares dos Santos, R.; Teixeira, A.

    2014-01-01

    In this paper we study a random walk in a one-dimensional dynamic random environment consisting of a collection of independent particles performing simple symmetric random walks in a Poisson equilibrium with density ¿¿(0,8). At each step the random walk performs a nearest-neighbour jump, moving to

  13. Contributions of Platform Motion to Simulator Training Effectiveness: Study II--Aerobatics. Interim Report for Period March 1976-November 1977.

    Science.gov (United States)

    Martin, Elizabeth L.; Waag, Wayne L.

    A transfer-of-training design was used to evaluate the contributions of simulator training with synergistic six-degrees-of-freedom platform motion to aerobatic skills acquisition in the novice pilot. Thirty-six undergraduate pilot trainees were randomly assigned to one of three treatment groups: motion, no-motion, and control. Those in the control…

  14. Ground motion effects

    Energy Technology Data Exchange (ETDEWEB)

    Blume, J A [John A. Blume and Associates, San Francisco, CA (United States)

    1969-07-01

    Ground motion caused by natural earthquakes or by nuclear explosion causes buildings and other structures to respond in such manner as possibly to have high unit stresses and to be subject to damage or-in some cases-collapse. Even minor damage may constitute a hazard to persons within or adjacent to buildings. The risk of damage may well be the governing restraint on the uses of nuclear energy for peaceful purposes. Theory is advanced regarding structural-dynamic response but real buildings and structures are complex, highly variable, and often difficult to model realistically. This paper discusses the state of knowledge, the art of damage prediction and safety precautions, and shows ground motion effects from explosions of underground nuclear devices in the continental United States including events Salmon, Gasbuggy, Boxcar, Faultless and Benham. (author)

  15. Ground motion effects

    International Nuclear Information System (INIS)

    Blume, J.A.

    1969-01-01

    Ground motion caused by natural earthquakes or by nuclear explosion causes buildings and other structures to respond in such manner as possibly to have high unit stresses and to be subject to damage or-in some cases-collapse. Even minor damage may constitute a hazard to persons within or adjacent to buildings. The risk of damage may well be the governing restraint on the uses of nuclear energy for peaceful purposes. Theory is advanced regarding structural-dynamic response but real buildings and structures are complex, highly variable, and often difficult to model realistically. This paper discusses the state of knowledge, the art of damage prediction and safety precautions, and shows ground motion effects from explosions of underground nuclear devices in the continental United States including events Salmon, Gasbuggy, Boxcar, Faultless and Benham. (author)

  16. Motion of the esophagus due to cardiac motion.

    Directory of Open Access Journals (Sweden)

    Jacob Palmer

    Full Text Available When imaging studies (e.g. CT are used to quantify morphological changes in an anatomical structure, it is necessary to understand the extent and source of motion which can give imaging artifacts (e.g. blurring or local distortion. The objective of this study was to assess the magnitude of esophageal motion due to cardiac motion. We used retrospective electrocardiogram-gated contrast-enhanced computed tomography angiography images for this study. The anatomic region from the carina to the bottom of the heart was taken at deep-inspiration breath hold with the patients' arms raised above their shoulders, in a position similar to that used for radiation therapy. The esophagus was delineated on the diastolic phase of cardiac motion, and deformable registration was used to sequentially deform the images in nearest-neighbor phases among the 10 cardiac phases, starting from the diastolic phase. Using the 10 deformation fields generated from the deformable registration, the magnitude of the extreme displacements was then calculated for each voxel, and the mean and maximum displacement was calculated for each computed tomography slice for each patient. The average maximum esophageal displacement due to cardiac motion for all patients was 5.8 mm (standard deviation: 1.6 mm, maximum: 10.0 mm in the transverse direction. For 21 of 26 patients, the largest esophageal motion was found in the inferior region of the heart; for the other patients, esophageal motion was approximately independent of superior-inferior position. The esophagus motion was larger at cardiac phases where the electrocardiogram R-wave occurs. In conclusion, the magnitude of esophageal motion near the heart due to cardiac motion is similar to that due to other sources of motion, including respiratory motion and intra-fraction motion. A larger cardiac motion will result into larger esophagus motion in a cardiac cycle.

  17. Brownian Optimal Stopping and Random Walks

    International Nuclear Information System (INIS)

    Lamberton, D.

    2002-01-01

    One way to compute the value function of an optimal stopping problem along Brownian paths consists of approximating Brownian motion by a random walk. We derive error estimates for this type of approximation under various assumptions on the distribution of the approximating random walk

  18. Why do adults with dyslexia have poor global motion sensitivity?

    Directory of Open Access Journals (Sweden)

    Elizabeth eConlon

    2013-12-01

    Full Text Available Two experiments aimed to determine why adults with dyslexia have higher global motion thresholds than typically reading controls. In Experiment 1, the dot density and number of animation frames presented in the dot stimulus were manipulated because of findings that use of a high dot density can normalise coherence thresholds in individuals with dyslexia. Dot densities were 14.15 dots/deg2 and 3.54 dots/deg2. These were presented for five (84ms or eight (134ms frames. The dyslexia group had higher coherence thresholds in all conditions than controls. However, in the high dot density, long duration condition, both reader groups had the lowest thresholds indicating normal temporal recruitment. These results indicated that the dyslexia group could sample the additional signals dots over space and then integrate these with the same efficiency as controls. In Experiment 2, we determined whether briefly presenting a fully coherent prime moving in either the same or opposite direction of motion to a partially coherent test stimulus would systematically increase and decrease global motion thresholds in the reader groups. When the direction of motion in the prime and test was the same, global motion thresholds increased for both reader groups. The increase in coherence thresholds was significantly greater for the dyslexia group. When the motion of the prime and test were presented in opposite directions, coherence thresholds were reduced in both groups. No group threshold differences were found. We concluded that the global motion processing deficit found in adults with dyslexia can be explained by undersampling of the target motion signals. This might occur because of difficulties directing attention to the relevant motion signals in the random dot pattern, and not a specific difficulty integrating global motion signals. These effects are most likely to occur in the group with dyslexia when more complex computational processes are required to process

  19. Why do adults with dyslexia have poor global motion sensitivity?

    Science.gov (United States)

    Conlon, Elizabeth G; Lilleskaret, Gry; Wright, Craig M; Stuksrud, Anne

    2013-01-01

    Two experiments aimed to determine why adults with dyslexia have higher global motion thresholds than typically reading controls. In Experiment 1, the dot density and number of animation frames presented in the dot stimulus were manipulated because of findings that use of a high dot density can normalize coherence thresholds in individuals with dyslexia. Dot densities were 14.15 and 3.54 dots/deg(2). These were presented for five (84 ms) or eight (134 ms) frames. The dyslexia group had higher coherence thresholds in all conditions than controls. However, in the high dot density, long duration condition, both reader groups had the lowest thresholds indicating normal temporal recruitment. These results indicated that the dyslexia group could sample the additional signals dots over space and then integrate these with the same efficiency as controls. In Experiment 2, we determined whether briefly presenting a fully coherent prime moving in either the same or opposite direction of motion to a partially coherent test stimulus would systematically increase and decrease global motion thresholds in the reader groups. When the direction of motion in the prime and test was the same, global motion thresholds increased for both reader groups. The increase in coherence thresholds was significantly greater for the dyslexia group. When the motion of the prime and test were presented in opposite directions, coherence thresholds were reduced in both groups. No group threshold differences were found. We concluded that the global motion processing deficit found in adults with dyslexia can be explained by undersampling of the target motion signals. This might occur because of difficulties directing attention to the relevant motion signals in the random dot pattern, and not a specific difficulty integrating global motion signals. These effects are most likely to occur in the group with dyslexia when more complex computational processes are required to process global motion.

  20. Motional spin relaxation in photoexcited triplet states

    International Nuclear Information System (INIS)

    Harryvan, D.; Faassen, E. van

    1997-01-01

    Transient EPR experiments were performed on photoexcited spin triplet states of the luminescent dye EOSIN-Y in diluted (order of 1 nMol) frozen propane-1-ol solutions at various temperatures. Photoexcitation was achieved by irradiation with intense, short laser pulses. The details of the spin relaxation, in particular the dependence on time, magnetic field and microwave field strength are all reproduced by a model which computes the total magnetization in a population of photoexcited triplet states undergoing random reorientational motion. Using this model, we estimated the motional correlation times to be around a microsecond. This timescale is two orders of magnitude slower than the phase memory time of the triplets. (author)

  1. Force and motion

    CERN Document Server

    Robertson, William C

    2002-01-01

    Intimidated by inertia? Frightened by forces? Mystified by Newton s law of motion? You re not alone and help is at hand. The stop Faking It! Series is perfect for science teachers, home-schoolers, parents wanting to help with homework all of you who need a jargon-free way to learn the background for teaching middle school physical science with confidence. With Bill Roberton as your friendly, able but somewhat irreverent guide, you will discover you CAN come to grips with the basics of force and motion. Combining easy-to-understand explanations with activities using commonly found equipment, this book will lead you through Newton s laws to the physics of space travel. The book is as entertaining as it is informative. Best of all, the author understands the needs of adults who want concrete examples, hands-on activities, clear language, diagrams and yes, a certain amount of empathy. Ideas For Use Newton's laws, and all of the other motion principles presented in this book, do a good job of helping us to underst...

  2. Parallel search for conjunctions with stimuli in apparent motion.

    Science.gov (United States)

    Casco, C; Ganis, G

    1999-01-01

    A series of experiments was conducted to determine whether apparent motion tends to follow the similarity rule (i.e. is attribute-specific) and to investigate the underlying mechanism. Stimulus duration thresholds were measured during a two-alternative forced-choice task in which observers detected either the location or the motion direction of target groups defined by the conjunction of size and orientation. Target element positions were randomly chosen within a nominally defined rectangular subregion of the display (target region). The target region was presented either statically (followed by a 250 ms duration mask) or dynamically, displaced by a small distance (18 min of arc) from frame to frame. In the motion display, the position of both target and background elements was changed randomly from frame to frame within the respective areas to abolish spatial correspondence over time. Stimulus duration thresholds were lower in the motion than in the static task, indicating that target detection in the dynamic condition does not rely on the explicit identification of target elements in each static frame. Increasing the distractor-to-target ratio was found to reduce detectability in the static, but not in the motion task. This indicates that the perceptual segregation of the target is effortless and parallel with motion but not with static displays. The pattern of results holds regardless of the task or search paradigm employed. The detectability in the motion condition can be improved by increasing the number of frames and/or by reducing the width of the target area. Furthermore, parallel search in the dynamic condition can be conducted with both short-range and long-range motion stimuli. Finally, apparent motion of conjunctions is insufficient on its own to support location decision and is disrupted by random visual noise. Overall, these findings show that (i) the mechanism underlying apparent motion is attribute-specific; (ii) the motion system mediates temporal

  3. Thermal-mechanical deformation modelling of soft tissues for thermal ablation.

    Science.gov (United States)

    Li, Xin; Zhong, Yongmin; Jazar, Reza; Subic, Aleksandar

    2014-01-01

    Modeling of thermal-induced mechanical behaviors of soft tissues is of great importance for thermal ablation. This paper presents a method by integrating the heating process with thermal-induced mechanical deformations of soft tissues for simulation and analysis of the thermal ablation process. This method combines bio-heat transfer theories, constitutive elastic material law under thermal loads as well as non-rigid motion dynamics to predict and analyze thermal-mechanical deformations of soft tissues. The 3D governing equations of thermal-mechanical soft tissue deformation are discretized by using the finite difference scheme and are subsequently solved by numerical algorithms. Experimental results show that the proposed method can effectively predict the thermal-induced mechanical behaviors of soft tissues, and can be used for the thermal ablation therapy to effectively control the delivered heat energy for cancer treatment.

  4. Random walk of passive tracers among randomly moving obstacles.

    Science.gov (United States)

    Gori, Matteo; Donato, Irene; Floriani, Elena; Nardecchia, Ilaria; Pettini, Marco

    2016-04-14

    This study is mainly motivated by the need of understanding how the diffusion behavior of a biomolecule (or even of a larger object) is affected by other moving macromolecules, organelles, and so on, inside a living cell, whence the possibility of understanding whether or not a randomly walking biomolecule is also subject to a long-range force field driving it to its target. By means of the Continuous Time Random Walk (CTRW) technique the topic of random walk in random environment is here considered in the case of a passively diffusing particle among randomly moving and interacting obstacles. The relevant physical quantity which is worked out is the diffusion coefficient of the passive tracer which is computed as a function of the average inter-obstacles distance. The results reported here suggest that if a biomolecule, let us call it a test molecule, moves towards its target in the presence of other independently interacting molecules, its motion can be considerably slowed down.

  5. Dynamic pathways to mediate reactions buried in thermal fluctuations. I. Time-dependent normal form theory for multidimensional Langevin equation.

    Science.gov (United States)

    Kawai, Shinnosuke; Komatsuzaki, Tamiki

    2009-12-14

    We present a novel theory which enables us to explore the mechanism of reaction selectivity and robust functions in complex systems persisting under thermal fluctuation. The theory constructs a nonlinear coordinate transformation so that the equation of motion for the new reaction coordinate is independent of the other nonreactive coordinates in the presence of thermal fluctuation. In this article we suppose that reacting systems subject to thermal noise are described by a multidimensional Langevin equation without a priori assumption for the form of potential. The reaction coordinate is composed not only of all the coordinates and velocities associated with the system (solute) but also of the random force exerted by the environment (solvent) with friction constants. The sign of the reaction coordinate at any instantaneous moment in the region of a saddle determines the fate of the reaction, i.e., whether the reaction will proceed through to the products or go back to the reactants. By assuming the statistical properties of the random force, one can know a priori a well-defined boundary of the reaction which separates the full position-velocity space in the saddle region into mainly reactive and mainly nonreactive regions even under thermal fluctuation. The analytical expression of the reaction coordinate provides the firm foundation on the mechanism of how and why reaction proceeds in thermal fluctuating environments.

  6. Effect of thermal friction on the generation and transport of interstitial defects in irradiated metals

    CERN Document Server

    Dudarev, S L

    2002-01-01

    Generation of interstitial and vacancy defects under 14.1 MeV neutron irradiation is expected to drive the evolution of microstructure of materials in a future fusion power station. We investigate effects of thermal friction associated with the interaction between mobile clusters of interstitial atoms produced in collision cascades and phonon excitations. Phonons give rise to the random Brownian motion of clusters in the crystal lattice. Phonon excitations are also responsible for the dissipation of energy of rapidly moving clusters formed at the periphery of collision cascades. We investigate how the coefficient of thermal friction depends on the structure of clusters. We also discuss implications of our findings for understanding the origin of higher resistance of bcc metals to irradiation and the connection between this phenomenon and the long-range effect observed in experiments on ion implantation.

  7. Computational micromagnetics: prediction of time dependent and thermal properties

    International Nuclear Information System (INIS)

    Schrefl, T.; Scholz, W.; Suess, Dieter; Fidler, J.

    2001-01-01

    Finite element modeling treats magnetization processes on a length scale of several nanometers and thus gives a quantitative correlation between the microstructure and the magnetic properties of ferromagnetic materials. This work presents a novel finite element/boundary element micro-magnetics solver that combines a wavelet-based matrix compression technique for magnetostatic field calculations with a BDF/GMRES method for the time integration of the Gilbert equation of motion. The simulations show that metastable energy minima and nonuniform magnetic states within the grains are important factors in the reversal dynamics at finite temperature. The numerical solution of the Gilbert equation shows how reversed domains nucleate and expand. The switching time of submicron magnetic elements depends on the shape of the elements. Elements with slanted ends decrease the overall reversal time, as a transverse demagnetizing field suppresses oscillations of the magnetization. Thermal activated processes can be included adding a random thermal field to the effective magnetic field. Thermally assisted reversal was studied for CoCrPtTa thin-film media

  8. Non-Markovian quantum Brownian motion in one dimension in electric fields

    Science.gov (United States)

    Shen, H. Z.; Su, S. L.; Zhou, Y. H.; Yi, X. X.

    2018-04-01

    Quantum Brownian motion is the random motion of quantum particles suspended in a field (or an effective field) resulting from their collision with fast-moving modes in the field. It provides us with a fundamental model to understand various physical features concerning open systems in chemistry, condensed-matter physics, biophysics, and optomechanics. In this paper, without either the Born-Markovian or rotating-wave approximation, we derive a master equation for a charged-Brownian particle in one dimension coupled with a thermal reservoir in electric fields. The effect of the reservoir and the electric fields is manifested as time-dependent coefficients and coherent terms, respectively, in the master equation. The two-photon correlation between the Brownian particle and the reservoir can induce nontrivial squeezing dynamics to the particle. We derive a current equation including the source from the driving fields, transient current from the system flowing into the environment, and the two-photon current caused by the non-rotating-wave term. The presented results then are compared with that given by the rotating-wave approximation in the weak-coupling limit, and these results are extended to a more general quantum network involving an arbitrary number of coupled-Brownian particles. The presented formalism might open a way to better understand exactly the non-Markovian quantum network.

  9. Tuning for temporal interval in human apparent motion detection.

    Science.gov (United States)

    Bours, Roger J E; Stuur, Sanne; Lankheet, Martin J M

    2007-01-08

    Detection of apparent motion in random dot patterns requires correlation across time and space. It has been difficult to study the temporal requirements for the correlation step because motion detection also depends on temporal filtering preceding correlation and on integration at the next levels. To specifically study tuning for temporal interval in the correlation step, we performed an experiment in which prefiltering and postintegration were held constant and in which we used a motion stimulus containing coherent motion for a single interval value only. The stimulus consisted of a sparse random dot pattern in which each dot was presented in two frames only, separated by a specified interval. On each frame, half of the dots were refreshed and the other half was a displaced reincarnation of the pattern generated one or several frames earlier. Motion energy statistics in such a stimulus do not vary from frame to frame, and the directional bias in spatiotemporal correlations is similar for different interval settings. We measured coherence thresholds for left-right direction discrimination by varying motion coherence levels in a Quest staircase procedure, as a function of both step size and interval. Results show that highest sensitivity was found for an interval of 17-42 ms, irrespective of viewing distance. The falloff at longer intervals was much sharper than previously described. Tuning for temporal interval was largely, but not completely, independent of step size. The optimal temporal interval slightly decreased with increasing step size. Similarly, the optimal step size decreased with increasing temporal interval.

  10. EDITORIAL: Nanotechnology in motion Nanotechnology in motion

    Science.gov (United States)

    Demming, Anna

    2012-02-01

    , Toshio Ando from the University of Kanazawa provides an overview of developments that have allowed atomic force microscopy to move from rates of the order of one frame a minute to over a thousand frames per second in constant height mode, as reported by Mervyn Miles and colleagues at Bristol University and University College London [8]. Among the pioneers in the field, Ando's group demonstrated the ability to record the Brownian motion of myosin V molecules on mica with image capture rates of 100 x 100 pixels in 80 ms over a decade ago [9]. The developments unleash the potential of atomic force microscopy to observe the dynamics of biological and materials systems. If seeing is believing, the ability to present real motion pictures of the nanoworld cannot fail to capture the public imagination and stimulate burgeoning new avenues of scientific endeavour. Nearly 350 years on from the publication Micrographia, images in microscopy have moved from the page to the movies. References [1] Binnig G, Quate C F, and Gerber Ch 1986 Phys. Rev. Lett. 56 930-3 [2] Ando T 2012 Nanotechnology 23 062001 [3] J G 1934 Nature 134 635-6 [4] Bharadwaj P, Anger P and Novotny L 2007 Nanotechnology 18 044017 [5] The Nobel Prize in Physics 1986 Nobelprize.org [6] Kim K K, Reina A, Shi Y, Park H, Li L-J, Lee Y H and Kong J 2010 Nanotechnology 21 285205 [7] Phillips D B, Grieve J A, Olof S N, Kocher S J, Bowman R, Padgett M J, Miles M J and Carberry D M 2011 Nanotechnology 22 285503 [8] Picco L M, Bozec L, Ulcinas A, Engledew D J, Antognozzi M, Horton M A and Miles M J 2007 Nanotechnology 18 044030 [9] Ando T, Kodera N, Takai E, Maruyama D, Saito K and Toda A 2001 Proc. Natl. Acad. Sci. 98 12468

  11. Human motion simulation predictive dynamics

    CERN Document Server

    Abdel-Malek, Karim

    2013-01-01

    Simulate realistic human motion in a virtual world with an optimization-based approach to motion prediction. With this approach, motion is governed by human performance measures, such as speed and energy, which act as objective functions to be optimized. Constraints on joint torques and angles are imposed quite easily. Predicting motion in this way allows one to use avatars to study how and why humans move the way they do, given specific scenarios. It also enables avatars to react to infinitely many scenarios with substantial autonomy. With this approach it is possible to predict dynamic motion without having to integrate equations of motion -- rather than solving equations of motion, this approach solves for a continuous time-dependent curve characterizing joint variables (also called joint profiles) for every degree of freedom. Introduces rigorous mathematical methods for digital human modelling and simulation Focuses on understanding and representing spatial relationships (3D) of biomechanics Develops an i...

  12. Random magnetism

    International Nuclear Information System (INIS)

    Tahir-Kheli, R.A.

    1975-01-01

    A few simple problems relating to random magnetic systems are presented. Translational symmetry, only on the macroscopic scale, is assumed for these systems. A random set of parameters, on the microscopic scale, for the various regions of these systems is also assumed. A probability distribution for randomness is obeyed. Knowledge of the form of these probability distributions, is assumed in all cases [pt

  13. Time-averaged MSD of Brownian motion

    International Nuclear Information System (INIS)

    Andreanov, Alexei; Grebenkov, Denis S

    2012-01-01

    We study the statistical properties of the time-averaged mean-square displacements (TAMSD). This is a standard non-local quadratic functional for inferring the diffusion coefficient from an individual random trajectory of a diffusing tracer in single-particle tracking experiments. For Brownian motion, we derive an exact formula for the Laplace transform of the probability density of the TAMSD by mapping the original problem onto chains of coupled harmonic oscillators. From this formula, we deduce the first four cumulant moments of the TAMSD, the asymptotic behavior of the probability density and its accurate approximation by a generalized Gamma distribution

  14. Time-averaged MSD of Brownian motion

    Science.gov (United States)

    Andreanov, Alexei; Grebenkov, Denis S.

    2012-07-01

    We study the statistical properties of the time-averaged mean-square displacements (TAMSD). This is a standard non-local quadratic functional for inferring the diffusion coefficient from an individual random trajectory of a diffusing tracer in single-particle tracking experiments. For Brownian motion, we derive an exact formula for the Laplace transform of the probability density of the TAMSD by mapping the original problem onto chains of coupled harmonic oscillators. From this formula, we deduce the first four cumulant moments of the TAMSD, the asymptotic behavior of the probability density and its accurate approximation by a generalized Gamma distribution.

  15. Action Video Games Improve Direction Discrimination of Parafoveal Translational Global Motion but Not Reaction Times.

    Science.gov (United States)

    Pavan, Andrea; Boyce, Matthew; Ghin, Filippo

    2016-10-01

    Playing action video games enhances visual motion perception. However, there is psychophysical evidence that action video games do not improve motion sensitivity for translational global moving patterns presented in fovea. This study investigates global motion perception in action video game players and compares their performance to that of non-action video game players and non-video game players. Stimuli were random dot kinematograms presented in the parafovea. Observers discriminated the motion direction of a target random dot kinematogram presented in one of the four visual quadrants. Action video game players showed lower motion coherence thresholds than the other groups. However, when the task was performed at threshold, we did not find differences between groups in terms of distributions of reaction times. These results suggest that action video games improve visual motion sensitivity in the near periphery of the visual field, rather than speed response. © The Author(s) 2016.

  16. Ultrafast Thermal Transport at Interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Cahill, David [Univ. of Illinois, Champaign, IL (United States); Murphy, Catherine [Univ. of Illinois, Champaign, IL (United States); Martin, Lane [Univ. of Illinois, Champaign, IL (United States)

    2014-10-21

    Our research program on Ultrafast Thermal Transport at Interfaces advanced understanding of the mesoscale science of heat conduction. At the length and time scales of atoms and atomic motions, energy is transported by interactions between single-particle and collective excitations. At macroscopic scales, entropy, temperature, and heat are the governing concepts. Key gaps in fundamental knowledge appear at the transitions between these two regimes. The transport of thermal energy at interfaces plays a pivotal role in these scientific issues. Measurements of heat transport with ultrafast time resolution are needed because picoseconds are the fundamental scales where the lack of equilibrium between various thermal excitations becomes a important factor in the transport physics. A critical aspect of our work has been the development of experimental methods and model systems that enabled more precise and sensitive investigations of nanoscale thermal transport.

  17. Temporomandibular joint motion

    International Nuclear Information System (INIS)

    Maeda, M.; Kawamura, Y.; Matsuda, T.; Itou, S.; Odori, T.; Ishii, Y.; Torizuka, K.

    1990-01-01

    This paper evaluates MR imaging with the therapeutic effect after splint therapy in internal derangement of the temporomandibular joint (TMJ). Fifteen patients (19 TMJs) with internal derangement of the TMJ and five normal volunteers (10 TMJs) were examined with sagittal T1-weighted spin-echo and gradient recalled acquisition in a steady state (GRASS) MR imaging. MR studies of the patients undergoing splint therapy were performed with an without splints. Pseudodynamic images of TMJ motion provide information that was not available from spin-echo T1-weighted images

  18. Motion Capturing Emotions

    OpenAIRE

    Wood Karen; Cisneros Rosemary E.; Whatley Sarah

    2017-01-01

    The paper explores the activities conducted as part of WhoLoDancE: Whole Body Interaction Learning for Dance Education which is an EU-funded Horizon 2020 project. In particular, we discuss the motion capture sessions that took place at Motek, Amsterdam as well as the dancers’ experience of being captured and watching themselves or others as varying visual representations through the HoloLens. HoloLens is Microsoft’s first holographic computer that you wear as you would a pair of glasses. The ...

  19. Electromechanical motion devices

    CERN Document Server

    Krause, Paul C; Pekarek, Steven D

    2012-01-01

    This text provides a basic treatment of modern electric machine analysis that gives readers the necessary background for comprehending the traditional applications and operating characteristics of electric machines-as well as their emerging applications in modern power systems and electric drives, such as those used in hybrid and electric vehicles. Through the appropriate use of reference frame theory, Electromagnetic Motion Devices, Second Edition introduces readers to field-oriented control of induction machines, constant-torque, and constant-power control of dc, permanent-magnet ac

  20. Patellofemoral joint motion

    International Nuclear Information System (INIS)

    Stanford, W.; Phelan, J.; Albright, J.; Kathol, M.; Rooholamini, S.A.; El-Khoury, G.Y.; Palutsis, G.R.

    1988-01-01

    This paper describes the use of ultrafast computed tomography (CT) to obtain dynamic images of the patellofemoral joint during active motion. Thirty-eight patients underwent measurements of tangent offset, bisect offset, congruence angle, patellar tilt angle, lateral patellofemoral angle, sulcus angle, and sulcus depth made during leg movement. Selected parameters were compared with Merchant views. Significant correlations were obtained between Merchant views and comparable ultrafast CT views for all parameters except sulcus angle. Correlations between the other parameters were poor. Cine strips showed two patterns of movement; the patella remained centered either throughout excursion or until the last 20 0 of full extension, when it would sublux laterally

  1. Infrasonic induced ground motions

    Science.gov (United States)

    Lin, Ting-Li

    On January 28, 2004, the CERI seismic network recorded seismic signals generated by an unknown source. Our conclusion is that the acoustic waves were initiated by an explosive source near the ground surface. The meteorological temperature and effective sound speed profiles suggested existence of an efficient near-surface waveguide that allowed the acoustic disturbance to propagate to large distances. An explosion occurring in an area of forest and farms would have limited the number of eyewitnesses. Resolution of the source might be possible by experiment or by detailed analysis of the ground motion data. A seismo-acoustic array was built to investigate thunder-induced ground motions. Two thunder events with similar N-wave waveforms but different horizontal slownesses are chosen to evaluate the credibility of using thunder as a seismic source. These impulsive acoustic waves excited P and S reverberations in the near surface that depend on both the incident wave horizontal slowness and the velocity structure in the upper 30 meters. Nineteen thunder events were chosen to further investigate the seismo-acoustic coupling. The consistent incident slowness differences between acoustic pressure and ground motions suggest that ground reverberations were first initiated somewhat away from the array. Acoustic and seismic signals were used to generate the time-domain transfer function through the deconvolution technique. Possible non-linear interaction for acoustic propagation into the soil at the surface was observed. The reverse radial initial motions suggest a low Poisson's ratio for the near-surface layer. The acoustic-to-seismic transfer functions show a consistent reverberation series of the Rayleigh wave type, which has a systematic dispersion relation to incident slownesses inferred from the seismic ground velocity. Air-coupled Rayleigh wave dispersion was used to quantitatively constrain the near-surface site structure with constraints afforded by near-surface body

  2. Rotational motion in nuclei

    International Nuclear Information System (INIS)

    Bohr, A.

    1976-01-01

    Nuclear structure theories are reviewed concerned with nuclei rotational motion. The development of the deformed nucleus model facilitated a discovery of rotational spectra of nuclei. Comprehensive verification of the rotational scheme and a successful classification of corresponding spectra stimulated investigations of the rotational movement dynamics. Values of nuclear moments of inertia proved to fall between two marginal values corresponding to rotation of a solid and hydrodynamic pattern of an unrotating flow, respectively. The discovery of governing role of the deformation and a degree of a symmetry violence for determining rotational degrees of freedon is pointed out to pave the way for generalization of the rotational spectra

  3. Contrast thresholds for component motion with full and poor attention.

    Science.gov (United States)

    Tsuchiya, Naotsugu; Braun, Jochen

    2007-02-12

    We compare luminance-contrast-masking thresholds for fully and poorly attended stimuli, controlling attention with a demanding concurrent task. We use dynamic displays composed of discrete spatiotemporal wavelets, comparing three conditions ("single," "parallel," and "random"). In contrast to static displays, we do not find that attention modulates the "dipper" regime for masks of low luminance contrast. Nor does attention alter direction-selective masking by multiple wavelets moving in random directions, a condition designed to isolate effects on component motion. However, direction-selective masking by multiple wavelets moving in parallel is significantly reduced by attention. As the latter condition is expected to excite both component and pattern motion mechanisms, this implies that attention may alter the visual representation of pattern motion. In addition, attention exhibits its well-known effect of reducing lateral masking between nearby spatiotemporal wavelets.

  4. Thermal insulation

    International Nuclear Information System (INIS)

    Aspden, G.J.; Howard, R.S.

    1988-01-01

    The patent concerns high temperature thermal insulation of large vessels, such as the primary vessel of a liquid metal cooled nuclear reactor. The thermal insulation consists of multilayered thermal insulation modules, and each module comprises a number of metal sheet layers sandwiched between a back and front plate. The layers are linked together by straps and clips to control the thickness of the module. (U.K.)

  5. A synchronous surround increases the motion strength gain of motion.

    Science.gov (United States)

    Linares, Daniel; Nishida, Shin'ya

    2013-11-12

    Coherent motion detection is greatly enhanced by the synchronous presentation of a static surround (Linares, Motoyoshi, & Nishida, 2012). To further understand this contextual enhancement, here we measured the sensitivity to discriminate motion strength for several pedestal strengths with and without a surround. We found that the surround improved discrimination of low and medium motion strengths, but did not improve or even impaired discrimination of high motion strengths. We used motion strength discriminability to estimate the perceptual response function assuming additive noise and found that the surround increased the motion strength gain, rather than the response gain. Given that eye and body movements continuously introduce transients in the retinal image, it is possible that this strength gain occurs in natural vision.

  6. Stochastic Blind Motion Deblurring

    KAUST Repository

    Xiao, Lei

    2015-05-13

    Blind motion deblurring from a single image is a highly under-constrained problem with many degenerate solutions. A good approximation of the intrinsic image can therefore only be obtained with the help of prior information in the form of (often non-convex) regularization terms for both the intrinsic image and the kernel. While the best choice of image priors is still a topic of ongoing investigation, this research is made more complicated by the fact that historically each new prior requires the development of a custom optimization method. In this paper, we develop a stochastic optimization method for blind deconvolution. Since this stochastic solver does not require the explicit computation of the gradient of the objective function and uses only efficient local evaluation of the objective, new priors can be implemented and tested very quickly. We demonstrate that this framework, in combination with different image priors produces results with PSNR values that match or exceed the results obtained by much more complex state-of-the-art blind motion deblurring algorithms.

  7. Perceptually Uniform Motion Space.

    Science.gov (United States)

    Birkeland, Asmund; Turkay, Cagatay; Viola, Ivan

    2014-11-01

    Flow data is often visualized by animated particles inserted into a flow field. The velocity of a particle on the screen is typically linearly scaled by the velocities in the data. However, the perception of velocity magnitude in animated particles is not necessarily linear. We present a study on how different parameters affect relative motion perception. We have investigated the impact of four parameters. The parameters consist of speed multiplier, direction, contrast type and the global velocity scale. In addition, we investigated if multiple motion cues, and point distribution, affect the speed estimation. Several studies were executed to investigate the impact of each parameter. In the initial results, we noticed trends in scale and multiplier. Using the trends for the significant parameters, we designed a compensation model, which adjusts the particle speed to compensate for the effect of the parameters. We then performed a second study to investigate the performance of the compensation model. From the second study we detected a constant estimation error, which we adjusted for in the last study. In addition, we connect our work to established theories in psychophysics by comparing our model to a model based on Stevens' Power Law.

  8. Effects of Second-Order Sum- and Difference-Frequency Wave Forces on the Motion Response of a Tension-Leg Platform Considering the Set-down Motion

    Science.gov (United States)

    Wang, Bin; Tang, Yougang; Li, Yan; Cai, Runbo

    2018-04-01

    This paper presents a study on the motion response of a tension-leg platform (TLP) under first- and second-order wave forces, including the mean-drift force, difference and sum-frequency forces. The second-order wave force is calculated using the full-field quadratic transfer function (QTF). The coupled effect of the horizontal motions, such as surge, sway and yaw motions, and the set-down motion are taken into consideration by the nonlinear restoring matrix. The time-domain analysis with 50-yr random sea state is performed. A comparison of the results of different case studies is made to assess the influence of second-order wave force on the motions of the platform. The analysis shows that the second-order wave force has a major impact on motions of the TLP. The second-order difference-frequency wave force has an obvious influence on the low-frequency motions of surge and sway, and also will induce a large set-down motion which is an important part of heave motion. Besides, the second-order sum-frequency force will induce a set of high-frequency motions of roll and pitch. However, little influence of second-order wave force is found on the yaw motion.

  9. Randomized random walk on a random walk

    International Nuclear Information System (INIS)

    Lee, P.A.

    1983-06-01

    This paper discusses generalizations of the model introduced by Kehr and Kunter of the random walk of a particle on a one-dimensional chain which in turn has been constructed by a random walk procedure. The superimposed random walk is randomised in time according to the occurrences of a stochastic point process. The probability of finding the particle in a particular position at a certain instant is obtained explicitly in the transform domain. It is found that the asymptotic behaviour for large time of the mean-square displacement of the particle depends critically on the assumed structure of the basic random walk, giving a diffusion-like term for an asymmetric walk or a square root law if the walk is symmetric. Many results are obtained in closed form for the Poisson process case, and these agree with those given previously by Kehr and Kunter. (author)

  10. Quantitative PET image reconstruction employing nested expectation-maximization deconvolution for motion compensation

    NARCIS (Netherlands)

    Karakatsanis, Nicolas A.; Tsoumpas, Charalampos; Zaidi, Habib

    Bulk body motion may randomly occur during PET acquisitions introducing blurring, attenuation emission mismatches and, in dynamic PET, discontinuities in the measured time activity curves between consecutive frames. Meanwhile, dynamic PET scans are longer, thus increasing the probability of bulk

  11. Success and Failure of Parliamentary Motions: A Social Dilemma Approach.

    Science.gov (United States)

    Popping, Roel; Wittek, Rafael

    2015-01-01

    Parliamentary motions are a vital and frequently used element of political control in democratic regimes. Despite their high incidence and potential impact on the political fate of a government and its policies, we know relatively little about the conditions under which parliamentary motions are likely to be accepted or rejected. Current collective decision-making models use a voting power framework in which power and influence of the involved parties are the main predictors. We propose an alternative, social dilemma approach, according to which a motion's likelihood to be accepted depends on the severity of the social dilemma underlying the decision issue. Actor- and dilemma-centered hypotheses are developed and tested with data from a stratified random sample of 822 motions that have been voted upon in the Dutch Parliament between September 2009 and February 2011. The social dilemma structure of each motion is extracted through content coding, applying a cognitive mapping technique developed by Anthony, Heckathorn and Maser. Logistic regression analyses are in line with both, actor-centered and social-dilemma centered approaches, though the latter show stronger effect sizes. Motions have a lower chance to be accepted if voting potential is low, the proposer is not from the voting party, and if the problem underlying the motion reflects a prisoner's dilemma or a pure competition game as compared to a coordination game. The number of proposing parties or a battle of the sexes structure does not significantly affect the outcome.

  12. The application of mean field theory to image motion estimation.

    Science.gov (United States)

    Zhang, J; Hanauer, G G

    1995-01-01

    Previously, Markov random field (MRF) model-based techniques have been proposed for image motion estimation. Since motion estimation is usually an ill-posed problem, various constraints are needed to obtain a unique and stable solution. The main advantage of the MRF approach is its capacity to incorporate such constraints, for instance, motion continuity within an object and motion discontinuity at the boundaries between objects. In the MRF approach, motion estimation is often formulated as an optimization problem, and two frequently used optimization methods are simulated annealing (SA) and iterative-conditional mode (ICM). Although the SA is theoretically optimal in the sense of finding the global optimum, it usually takes many iterations to converge. The ICM, on the other hand, converges quickly, but its results are often unsatisfactory due to its "hard decision" nature. Previously, the authors have applied the mean field theory to image segmentation and image restoration problems. It provides results nearly as good as SA but with much faster convergence. The present paper shows how the mean field theory can be applied to MRF model-based motion estimation. This approach is demonstrated on both synthetic and real-world images, where it produced good motion estimates.

  13. Receptive fields for smooth pursuit eye movements and motion perception.

    Science.gov (United States)

    Debono, Kurt; Schütz, Alexander C; Spering, Miriam; Gegenfurtner, Karl R

    2010-12-01

    Humans use smooth pursuit eye movements to track moving objects of interest. In order to track an object accurately, motion signals from the target have to be integrated and segmented from motion signals in the visual context. Most studies on pursuit eye movements used small visual targets against a featureless background, disregarding the requirements of our natural visual environment. Here, we tested the ability of the pursuit and the perceptual system to integrate motion signals across larger areas of the visual field. Stimuli were random-dot kinematograms containing a horizontal motion signal, which was perturbed by a spatially localized, peripheral motion signal. Perturbations appeared in a gaze-contingent coordinate system and had a different direction than the main motion including a vertical component. We measured pursuit and perceptual direction discrimination decisions and found that both steady-state pursuit and perception were influenced most by perturbation angles close to that of the main motion signal and only in regions close to the center of gaze. The narrow direction bandwidth (26 angular degrees full width at half height) and small spatial extent (8 degrees of visual angle standard deviation) correspond closely to tuning parameters of neurons in the middle temporal area (MT). Copyright © 2010 Elsevier Ltd. All rights reserved.

  14. Cell motility as persistent random motion: Theories from experiments

    DEFF Research Database (Denmark)

    Selmeczi, D.; Mosler, S.; Hagedorn, P.H.

    2005-01-01

    Experimental time series for trajectories of motile cells may contain so much information that a systematic analysis will yield cell-type- specific motility models. Here we demonstrate how, using human keratinocytes and fibroblasts as examples. The two resulting models reflect the cells' differen...

  15. Directed motion emerging from two coupled random processes

    DEFF Research Database (Denmark)

    Ambjörnsson, T.; Lomholt, Michael Andersen; Metzler, R.

    2005-01-01

    detail, we develop a dynamical description of the process in terms of a (2+1)-variable master equation for the probability of having m monomers on the target side of the membrane with n bound chaperones at time t. Emphasis is put on the calculation of the mean first passage time as a function of total...... dynamics ( and ), we perform the adiabatic elimination of the fast variable n, and find that for a very long polymer , but with a smaller prefactor than for ratchet-like dynamics. We solve the general case numerically as a function of the dimensionless parameters λ, κ and γ, and compare to the three...

  16. Shannon versus Kullback-Leibler entropies in nonequilibrium random motion

    International Nuclear Information System (INIS)

    Garbaczewski, Piotr

    2005-01-01

    We analyze dynamical properties of the Shannon information entropy of a continuous probability distribution, which is driven by a standard diffusion process. This entropy choice is confronted with another option, employing the conditional Kullback-Leibler entropy. Both entropies discriminate among various probability distributions, either statically or in the time domain. An asymptotic approach towards equilibrium is typically monotonic in terms of the Kullback entropy. The Shannon entropy time rate needs not to be positive and is a sensitive indicator of the power transfer processes (removal/supply) due to an active environment. In the case of Smoluchowski diffusions, the Kullback entropy time rate coincides with the Shannon entropy 'production' rate

  17. The Humidity in a Low-Flow Dräger Fabius Anesthesia Workstation with or without Thermal Insulation or a Heat and Moisture Exchanger: A Prospective Randomized Clinical Trial.

    Science.gov (United States)

    de Oliveira, Sergius A R; Lucio, Lorena M C; Modolo, Norma S P; Hayashi, Yoko; Braz, Mariana G; de Carvalho, Lídia R; Braz, Leandro G; Braz, José Reinaldo C

    2017-01-01

    During anesthesia, as compared with intensive care, the time of the tracheal intubation is much shorter. An inhaled gas minimum humidity of 20 mgH2O.L-1 is recommended to reduce the deleterious effects of dry gas on the airways during anesthesia with tracheal intubation. The Fabius GS Premium® anesthesia workstation (Dräger Medical, Lübeck, Germany) has a built-in hotplate to heat gases in the breathing circuit. A heat and moisture exchanger (HME) is used to further heat and humidify the inhaled gas. The humidity of the gases in the breathing circuit is influenced by the ambient temperature. We compared the humidity of the inhaled gases from a low-flow Fabius anesthesia workstation with or without thermal insulation (TI) of the breathing circuit and with or without an HME. We conducted a prospective randomized trial in 41 adult female patients who underwent elective abdominal surgery. The patients were allocated into four groups according to the devices used to ventilate their lungs using a Dräger Fabius anesthesia workstation with a low gas flow (1 L.min-1): control, with TI, with an HME or with TI and an HME (TIHME). The mean temperature and humidity of the inhaled gases were measured during 2-h after connecting the patients to the breathing circuit. The mean inhaled gas temperature and absolute humidity were higher in the HME (29.2±1.3°C; 28.1±2.3 mgH2O·L-1) and TIHME (30.1±1.2°C; 29.4±2.0 mgH2O·L-1) groups compared with the control (27.5±1.0°C; 25.0±1.8 mgH2O·L-1) and TI (27.2±1.1°C; 24.9±1.8 mgH2O·L-1) groups (P = 0.003 and Phumidity level of inhaled gases to avoid damage to the tracheobronchial epithelia during anesthesia. TI of the breathing circuit does not increase the humidity of the inhaled gases, whereas inserting an HME increases the moisture of the inhaled gases closer to physiological values.

  18. Estimating network effect in geocenter motion: Theory

    Science.gov (United States)

    Zannat, Umma Jamila; Tregoning, Paul

    2017-10-01

    Geophysical models and their interpretations of several processes of interest, such as sea level rise, postseismic relaxation, and glacial isostatic adjustment, are intertwined with the need to realize the International Terrestrial Reference Frame. However, this realization needs to take into account the geocenter motion, that is, the motion of the center of figure of the Earth surface, due to, for example, deformation of the surface by earthquakes or hydrological loading effects. Usually, there is also a discrepancy, known as the network effect, between the theoretically convenient center of figure and the physically accessible center of network frames, because of unavoidable factors such as uneven station distribution, lack of stations in the oceans, disparity in the coverage between the two hemispheres, and the existence of tectonically deforming zones. Here we develop a method to estimate the magnitude of the network effect, that is, the error introduced by the incomplete sampling of the Earth surface, in measuring the geocenter motion, for a network of space geodetic stations of a fixed size N. For this purpose, we use, as our proposed estimate, the standard deviations of the changes in Helmert parameters measured by a random network of the same size N. We show that our estimate scales as 1/√N and give an explicit formula for it in terms of the vector spherical harmonics expansion of the displacement field. In a complementary paper we apply this formalism to coseismic displacements and elastic deformations due to surface water movements.

  19. Thermal insulation

    International Nuclear Information System (INIS)

    Pinsky, G.P.

    1977-01-01

    Thermal insulation for vessels and piping within the reactor containment area of nuclear power plants is disclosed. The thermal insulation of this invention can be readily removed and replaced from the vessels and piping for inservice inspection, can withstand repeated wettings and dryings, and can resist high temperatures for long periods of time. 4 claims, 3 figures

  20. Quincke random walkers

    Science.gov (United States)

    Pradillo, Gerardo; Heintz, Aneesh; Vlahovska, Petia

    2017-11-01

    The spontaneous rotation of a sphere in an applied uniform DC electric field (Quincke effect) has been utilized to engineer self-propelled particles: if the sphere is initially resting on a surface, it rolls. The Quincke rollers have been widely used as a model system to study collective behavior in ``active'' suspensions. If the applied field is DC, an isolated Quincke roller follows a straight line trajectory. In this talk, we discuss the design of a Quincke roller that executes a random-walk-like behavior. We utilize AC field - upon reversal of the field direction a fluctuation in the axis of rotation (which is degenerate in the plane perpendicular to the field and parallel to the surface) introduces randomness in the direction of motion. The MSD of an isolated Quincke walker depends on frequency, amplitude, and waveform of the electric field. Experiment and theory are compared. We also investigate the collective behavior of Quincke walkers,the transport of inert particles in a bath of Quincke walkers, and the spontaneous motion of a drop containing Quincke active particle. supported by NSF Grant CBET 1437545.

  1. Motion camouflage in three dimensions

    OpenAIRE

    Reddy, P. V.; Justh, E. W.; Krishnaprasad, P. S.

    2006-01-01

    We formulate and analyze a three-dimensional model of motion camouflage, a stealth strategy observed in nature. A high-gain feedback law for motion camouflage is formulated in which the pursuer and evader trajectories are described using natural Frenet frames (or relatively parallel adapted frames), and the corresponding natural curvatures serve as controls. The biological plausibility of the feedback law is discussed, as is its connection to missile guidance. Simulations illustrating motion ...

  2. Markerless motion estimation for motion-compensated clinical brain imaging

    Science.gov (United States)

    Kyme, Andre Z.; Se, Stephen; Meikle, Steven R.; Fulton, Roger R.

    2018-05-01

    Motion-compensated brain imaging can dramatically reduce the artifacts and quantitative degradation associated with voluntary and involuntary subject head motion during positron emission tomography (PET), single photon emission computed tomography (SPECT) and computed tomography (CT). However, motion-compensated imaging protocols are not in widespread clinical use for these modalities. A key reason for this seems to be the lack of a practical motion tracking technology that allows for smooth and reliable integration of motion-compensated imaging protocols in the clinical setting. We seek to address this problem by investigating the feasibility of a highly versatile optical motion tracking method for PET, SPECT and CT geometries. The method requires no attached markers, relying exclusively on the detection and matching of distinctive facial features. We studied the accuracy of this method in 16 volunteers in a mock imaging scenario by comparing the estimated motion with an accurate marker-based method used in applications such as image guided surgery. A range of techniques to optimize performance of the method were also studied. Our results show that the markerless motion tracking method is highly accurate (brain imaging and holds good promise for a practical implementation in clinical PET, SPECT and CT systems.

  3. Visual motion influences the contingent auditory motion aftereffect

    NARCIS (Netherlands)

    Vroomen, J.; de Gelder, B.

    2003-01-01

    In this study, we show that the contingent auditory motion aftereffect is strongly influenced by visual motion information. During an induction phase, participants listened to rightward-moving sounds with falling pitch alternated with leftward-moving sounds with rising pitch (or vice versa).

  4. Respiratory impact on motion sickness induced by linear motion

    NARCIS (Netherlands)

    Mert, A.; Klöpping-Ketelaars, I.; Bles, W.

    2009-01-01

    Motion sickness incidence (MSI) for vertical sinusoidal motion reaches a maximum at 0.167 Hz. Normal breathing frequency is close to this frequency. There is some evidence for synchronization of breathing with this stimulus frequency. If this enforced breathing takes place over a larger frequency

  5. 41 CFR 60-30.8 - Motions; disposition of motions.

    Science.gov (United States)

    2010-07-01

    ... a supporting memorandum. Within 10 days after a written motion is served, or such other time period... writing. If made at the hearing, motions may be stated orally; but the Administrative Law Judge may require that they be reduced to writing and filed and served on all parties in the same manner as a formal...

  6. Motion-encoded dose calculation through fluence/sinogram modification

    International Nuclear Information System (INIS)

    Lu, Weiguo; Olivera, Gustavo H.; Mackie, Thomas R.

    2005-01-01

    Conventional radiotherapy treatment planning systems rely on a static computed tomography (CT) image for planning and evaluation. Intra/inter-fraction patient motions may result in significant differences between the planned and the delivered dose. In this paper, we develop a method to incorporate the knowledge of intra/inter-fraction patient motion directly into the dose calculation. By decomposing the motion into a parallel (to beam direction) component and perpendicular (to beam direction) component, we show that the motion effects can be accounted for by simply modifying the fluence distribution (sinogram). After such modification, dose calculation is the same as those based on a static planning image. This method is superior to the 'dose-convolution' method because it is not based on 'shift invariant' assumption. Therefore, it deals with material heterogeneity and surface curvature very well. We test our method using extensive simulations, which include four phantoms, four motion patterns, and three plan beams. We compare our method with the 'dose-convolution' and the 'stochastic simulation' methods (gold standard). As for the homogeneous flat surface phantom, our method has similar accuracy as the 'dose-convolution' method. As for all other phantoms, our method outperforms the 'dose-convolution'. The maximum motion encoded dose calculation error using our method is within 4% of the gold standard. It is shown that a treatment planning system that is based on 'motion-encoded dose calculation' can incorporate random and systematic motion errors in a very simple fashion. Under this approximation, in principle, a planning target volume definition is not required, since it already accounts for the intra/inter-fraction motion variations and it automatically optimizes the cumulative dose rather than the single fraction dose

  7. Single molecule detection, thermal fluctuation and life

    Science.gov (United States)

    YANAGIDA, Toshio; ISHII, Yoshiharu

    2017-01-01

    Single molecule detection has contributed to our understanding of the unique mechanisms of life. Unlike artificial man-made machines, biological molecular machines integrate thermal noises rather than avoid them. For example, single molecule detection has demonstrated that myosin motors undergo biased Brownian motion for stepwise movement and that single protein molecules spontaneously change their conformation, for switching to interactions with other proteins, in response to thermal fluctuation. Thus, molecular machines have flexibility and efficiency not seen in artificial machines. PMID:28190869

  8. Standardized rendering from IR surveillance motion imagery

    Science.gov (United States)

    Prokoski, F. J.

    2014-06-01

    Government agencies, including defense and law enforcement, increasingly make use of video from surveillance systems and camera phones owned by non-government entities.Making advanced and standardized motion imaging technology available to private and commercial users at cost-effective prices would benefit all parties. In particular, incorporating thermal infrared into commercial surveillance systems offers substantial benefits beyond night vision capability. Face rendering is a process to facilitate exploitation of thermal infrared surveillance imagery from the general area of a crime scene, to assist investigations with and without cooperating eyewitnesses. Face rendering automatically generates greyscale representations similar to police artist sketches for faces in surveillance imagery collected from proximate locations and times to a crime under investigation. Near-realtime generation of face renderings can provide law enforcement with an investigation tool to assess witness memory and credibility, and integrate reports from multiple eyewitnesses, Renderings can be quickly disseminated through social media to warn of a person who may pose an immediate threat, and to solicit the public's help in identifying possible suspects and witnesses. Renderings are pose-standardized so as to not divulge the presence and location of eyewitnesses and surveillance cameras. Incorporation of thermal infrared imaging into commercial surveillance systems will significantly improve system performance, and reduce manual review times, at an incremental cost that will continue to decrease. Benefits to criminal justice would include improved reliability of eyewitness testimony and improved accuracy of distinguishing among minority groups in eyewitness and surveillance identifications.

  9. Random Fields

    Science.gov (United States)

    Vanmarcke, Erik

    1983-03-01

    Random variation over space and time is one of the few attributes that might safely be predicted as characterizing almost any given complex system. Random fields or "distributed disorder systems" confront astronomers, physicists, geologists, meteorologists, biologists, and other natural scientists. They appear in the artifacts developed by electrical, mechanical, civil, and other engineers. They even underlie the processes of social and economic change. The purpose of this book is to bring together existing and new methodologies of random field theory and indicate how they can be applied to these diverse areas where a "deterministic treatment is inefficient and conventional statistics insufficient." Many new results and methods are included. After outlining the extent and characteristics of the random field approach, the book reviews the classical theory of multidimensional random processes and introduces basic probability concepts and methods in the random field context. It next gives a concise amount of the second-order analysis of homogeneous random fields, in both the space-time domain and the wave number-frequency domain. This is followed by a chapter on spectral moments and related measures of disorder and on level excursions and extremes of Gaussian and related random fields. After developing a new framework of analysis based on local averages of one-, two-, and n-dimensional processes, the book concludes with a chapter discussing ramifications in the important areas of estimation, prediction, and control. The mathematical prerequisite has been held to basic college-level calculus.

  10. Visual motion perception predicts driving hazard perception ability.

    Science.gov (United States)

    Lacherez, Philippe; Au, Sandra; Wood, Joanne M

    2014-02-01

    To examine the basis of previous findings of an association between indices of driving safety and visual motion sensitivity and to examine whether this association could be explained by low-level changes in visual function. A total of 36 visually normal participants (aged 19-80 years) completed a battery of standard vision tests including visual acuity, contrast sensitivity and automated visual fields and two tests of motion perception including sensitivity for movement of a drifting Gabor stimulus and sensitivity for displacement in a random dot kinematogram (Dmin ). Participants also completed a hazard perception test (HPT), which measured participants' response times to hazards embedded in video recordings of real-world driving, which has been shown to be linked to crash risk. Dmin for the random dot stimulus ranged from -0.88 to -0.12 log minutes of arc, and the minimum drift rate for the Gabor stimulus ranged from 0.01 to 0.35 cycles per second. Both measures of motion sensitivity significantly predicted response times on the HPT. In addition, while the relationship involving the HPT and motion sensitivity for the random dot kinematogram was partially explained by the other visual function measures, the relationship with sensitivity for detection of the drifting Gabor stimulus remained significant even after controlling for these variables. These findings suggest that motion perception plays an important role in the visual perception of driving-relevant hazards independent of other areas of visual function and should be further explored as a predictive test of driving safety. Future research should explore the causes of reduced motion perception to develop better interventions to improve road safety. © 2012 The Authors. Acta Ophthalmologica © 2012 Acta Ophthalmologica Scandinavica Foundation.

  11. Thermal equilibrium, stability and burn control

    International Nuclear Information System (INIS)

    Cohn, D.

    1982-01-01

    A number of aspects of the thermal stability and equilibrium control of ignited tokamak plasma have been investigated. Examined approaches were passive control (the effect of radial motion, the effect of radial motion and small additional transport loss), active control (the compression and decompression of plasma, subignited operation with small amount of variable external heating, and density control), and thermal equilibrium control (additional power loss from impurity radiation and enhanced transport from increased ripple). One-D calculation has been made on thermal instability eigen-modes. It was found that for electron thermal induction loss given by Alcator scaling and for neoclassical ion transport, there was at most one unstable mode with a temperature profile which maintains the temperature profile at thermal equilibrium. The effect of the coupling of temperature fluctuation and the fluctuation in major radius was investigated. Temperature driven radial motion combined with a small amount of ripple transport loss was found to be a very effective mechanism for passive thermal stability control. (Kato, T.)

  12. Algorithmic Issues in Modeling Motion

    DEFF Research Database (Denmark)

    Agarwal, P. K; Guibas, L. J; Edelsbrunner, H.

    2003-01-01

    This article is a survey of research areas in which motion plays a pivotal role. The aim of the article is to review current approaches to modeling motion together with related data structures and algorithms, and to summarize the challenges that lie ahead in producing a more unified theory of mot...

  13. Rolling motion in moving droplets

    Indian Academy of Sciences (India)

    motions. The two limits of a thin sheet-like drop in sliding motion on a surface, and a spherical drop in roll, have been extensively .... rigid body rotation. The solid body rotation makes sense in the context of small Reynolds. (Re) number flows ...

  14. Commercially available video motion detectors

    International Nuclear Information System (INIS)

    1979-01-01

    A market survey of commercially available video motion detection systems was conducted by the Intrusion Detection Systems Technology Division of Sandia Laboratories. The information obtained from this survey is summarized in this report. The cutoff date for this information is May 1978. A list of commercially available video motion detection systems is appended

  15. Motion simulator with exchangeable unit

    NARCIS (Netherlands)

    Mulder, J.A.; Beukers, A.; Baarspul, M.; Van Tooren, M.J.; De Winter, S.E.E.

    2001-01-01

    A motion simulator provided with a movable housing, preferably carried by a number of length-adjustable legs, in which housing projection means are arranged for visual information supply, while in the housing a control environment of a motion apparatus to be simulated is situated, the control

  16. Nanoparticle mediated micromotor motion

    Science.gov (United States)

    Liu, Mei; Liu, Limei; Gao, Wenlong; Su, Miaoda; Ge, Ya; Shi, Lili; Zhang, Hui; Dong, Bin; Li, Christopher Y.

    2015-03-01

    In this paper, we report the utilization of nanoparticles to mediate the motion of a polymer single crystal catalytic micromotor. Micromotors have been fabricated by directly self-assembling functional nanoparticles (platinum and iron oxide nanoparticles) onto one or both sides of two-dimensional polymer single crystals. We show that the moving velocity of these micromotors in fluids can be readily tuned by controlling the nanoparticles' surface wettability and catalytic activity. A 3 times velocity increase has been achieved for a hydrophobic micromotor as opposed to the hydrophilic ones. Furthermore, we demonstrate that the catalytic activity of platinum nanoparticles inside the micromotor can be enhanced by their synergetic interactions with iron oxide nanoparticles and an electric field. Both strategies lead to dramatically increased moving velocities, with the highest value reaching ~200 μm s-1. By decreasing the nanoparticles' surface wettability and increasing their catalytic activity, a maximum of a ~10-fold increase in the moving speed of the nanoparticle based micromotor can be achieved. Our results demonstrate the advantages of using nanoparticles in micromotor systems.In this paper, we report the utilization of nanoparticles to mediate the motion of a polymer single crystal catalytic micromotor. Micromotors have been fabricated by directly self-assembling functional nanoparticles (platinum and iron oxide nanoparticles) onto one or both sides of two-dimensional polymer single crystals. We show that the moving velocity of these micromotors in fluids can be readily tuned by controlling the nanoparticles' surface wettability and catalytic activity. A 3 times velocity increase has been achieved for a hydrophobic micromotor as opposed to the hydrophilic ones. Furthermore, we demonstrate that the catalytic activity of platinum nanoparticles inside the micromotor can be enhanced by their synergetic interactions with iron oxide nanoparticles and an electric

  17. Random processes in nuclear reactors

    CERN Document Server

    Williams, M M R

    1974-01-01

    Random Processes in Nuclear Reactors describes the problems that a nuclear engineer may meet which involve random fluctuations and sets out in detail how they may be interpreted in terms of various models of the reactor system. Chapters set out to discuss topics on the origins of random processes and sources; the general technique to zero-power problems and bring out the basic effect of fission, and fluctuations in the lifetime of neutrons, on the measured response; the interpretation of power reactor noise; and associated problems connected with mechanical, hydraulic and thermal noise sources

  18. Thermal expansion

    International Nuclear Information System (INIS)

    Yun, Y.

    2015-01-01

    Thermal expansion of fuel pellet is an important property which limits the lifetime of the fuels in reactors, because it affects both the pellet and cladding mechanical interaction and the gap conductivity. By fitting a number of available measured data, recommended equations have been presented and successfully used to estimate thermal expansion coefficient of the nuclear fuel pellet. However, due to large scatter of the measured data, non-consensus data have been omitted in formulating the equations. Also, the equation is strongly governed by the lack of appropriate experimental data. For those reasons, it is important to develop theoretical methodologies to better describe thermal expansion behaviour of nuclear fuel. In particular, first-principles and molecular dynamics simulations have been certainly contributed to predict reliable thermal expansion without fitting the measured data. Furthermore, the two theoretical techniques have improved on understanding the change of fuel dimension by describing the atomic-scale processes associated with lattice expansion in the fuels. (author)

  19. Relativistic many-body theory of atomic transitions: the relativistic equation-of-motion approach

    International Nuclear Information System (INIS)

    Huang, K.N.

    1981-01-01

    An equation-of-motion approach is used to develop the relativistic many-body theory of atomic transitions. The relativistic equations of motion for transition matrices are formulated using techniques of quantum field theory. To reduce the equation of motion to a tractable form which is appropriate for numerical calculations, a graphical method is employed to resolve the complication arising from the antisymmetrization and angular momentum coupling. The relativistic equation-of-motion method allows an ab initio treatment of correlation and relativistic effects in both closed- and open-shell many-body systems. A special case of the present formulation reduces to the relativistic random-phase approximation

  20. Thermophoresis as persistent random walk

    International Nuclear Information System (INIS)

    Plyukhin, A.V.

    2009-01-01

    In a simple model of a continuous random walk a particle moves in one dimension with the velocity fluctuating between +v and -v. If v is associated with the thermal velocity of a Brownian particle and allowed to be position dependent, the model accounts readily for the particle's drift along the temperature gradient and recovers basic results of the conventional thermophoresis theory.

  1. Motion Capturing Emotions

    Directory of Open Access Journals (Sweden)

    Wood Karen

    2017-12-01

    Full Text Available The paper explores the activities conducted as part of WhoLoDancE: Whole Body Interaction Learning for Dance Education which is an EU-funded Horizon 2020 project. In particular, we discuss the motion capture sessions that took place at Motek, Amsterdam as well as the dancers’ experience of being captured and watching themselves or others as varying visual representations through the HoloLens. HoloLens is Microsoft’s first holographic computer that you wear as you would a pair of glasses. The study embraced four dance genres: Ballet, Contemporary, Flamenco and Greek Folk dance. We are specifically interested in the kinesthetic and emotional engagement with the moving body and what new corporeal awareness may be experienced. Positioning the moving, dancing body as fundamental to technological advancements, we discuss the importance of considering the dancer’s experience in the real and virtual space. Some of the artists involved in the project have offered their experiences, which are included, and they form the basis of the discussion. In addition, we discuss the affect of immersive environments, how these environments expand reality and what effect (emotionally and otherwise that has on the body. The research reveals insights into relationships between emotion, movement and technology and what new sensorial knowledge this evokes for the dancer.

  2. Measurement of shoulder motion fraction and motion ratio

    International Nuclear Information System (INIS)

    Kang, Yeong Han

    2006-01-01

    This study was to understand about the measurement of shoulder motion fraction and motion ratio. We proposed the radiological criterior of glenohumeral and scapulothoracic movement ratio. We measured the motion fraction of the glenohumeral and scapulothoracic movement using CR (computed radiological system) of arm elevation at neutral, 90 degree, full elevation. Central ray was 15 .deg., 19 .deg., 22 .deg. to the cephald for the parallel scapular spine, and the tilting of torso was external oblique 40 .deg., 36 .deg., 22 .deg. for perpendicular to glenohumeral surface. Healthful donor of 100 was divided 5 groups by age (20, 30, 40, 50, 60). The angle of glenohumeral motion and scapulothoracic motion could be taken from gross arm angle and radiological arm angle. We acquired 3 images at neutral, 90 .deg. and full elevation position and measured radiographic angle of glenoheumeral, scapulothoracic movement respectively. While the arm elevation was 90 .deg., the shoulder motion fraction was 1.22 (M), 1.70 (W) in right arm and 1.31, 1.54 in left. In full elevation, Right arm fraction was 1.63, 1.84 and left was 1.57, 1.32. In right dominant arm (78%), 90 .deg. and Full motion fraction was 1.58, 1.43, in left (22%) 1.82, 1.94. In generation 20, 90 .deg. and Full motion fraction was 1.56, 1.52, 30' was 1.82, 1.43, 40' was 1.23, 1.16, 50' was 1.80, 1.28,60' was 1.24, 1.75. There was not significantly by gender, dominant arm and age. The criteria of motion fraction was useful reference for clinical diagnosis the shoulder instability

  3. Locally Perturbed Random Walks with Unbounded Jumps

    OpenAIRE

    Paulin, Daniel; Szász, Domokos

    2010-01-01

    In \\cite{SzT}, D. Sz\\'asz and A. Telcs have shown that for the diffusively scaled, simple symmetric random walk, weak convergence to the Brownian motion holds even in the case of local impurities if $d \\ge 2$. The extension of their result to finite range random walks is straightforward. Here, however, we are interested in the situation when the random walk has unbounded range. Concretely we generalize the statement of \\cite{SzT} to unbounded random walks whose jump distribution belongs to th...

  4. Manipulation and controlled amplification of Brownian motion of microcantilever sensors

    International Nuclear Information System (INIS)

    Mehta, Adosh; Cherian, Suman; Hedden, David; Thundat, Thomas

    2001-01-01

    Microcantilevers, such as those used in atomic force microscopy, undergo Brownian motion due to mechanical thermal noise. The root mean square amplitude of the Brownian motion of a cantilever typically ranges from 0.01--0.1 nm, which limits its use in practical applications. Here we describe a technique by which the Brownian amplitude and the Q factor in air and water can be amplified by three and two orders of magnitude, respectively. This technique is similar to a positive feedback oscillator, wherein the Brownian motion of the vibrating cantilever controls the frequency output of the oscillator. This technique can be exploited to improve sensitivity of microcantilever-based chemical and biological sensors, especially for sensors in liquid environments

  5. QUANTUM MECHANICS. Quantum squeezing of motion in a mechanical resonator.

    Science.gov (United States)

    Wollman, E E; Lei, C U; Weinstein, A J; Suh, J; Kronwald, A; Marquardt, F; Clerk, A A; Schwab, K C

    2015-08-28

    According to quantum mechanics, a harmonic oscillator can never be completely at rest. Even in the ground state, its position will always have fluctuations, called the zero-point motion. Although the zero-point fluctuations are unavoidable, they can be manipulated. Using microwave frequency radiation pressure, we have manipulated the thermal fluctuations of a micrometer-scale mechanical resonator to produce a stationary quadrature-squeezed state with a minimum variance of 0.80 times that of the ground state. We also performed phase-sensitive, back-action evading measurements of a thermal state squeezed to 1.09 times the zero-point level. Our results are relevant to the quantum engineering of states of matter at large length scales, the study of decoherence of large quantum systems, and for the realization of ultrasensitive sensing of force and motion. Copyright © 2015, American Association for the Advancement of Science.

  6. Marker-Free Human Motion Capture

    DEFF Research Database (Denmark)

    Grest, Daniel

    Human Motion Capture is a widely used technique to obtain motion data for animation of virtual characters. Commercial optical motion capture systems are marker-based. This book is about marker-free motion capture and its possibilities to acquire motion from a single viewing direction. The focus...

  7. Motion perception in motion : how we perceive object motion during smooth pursuit eye movements

    NARCIS (Netherlands)

    Souman, J.L.

    2005-01-01

    Eye movements change the retinal image motion of objects in the visual field. When we make an eye movement, the image of a stationary object will move across the retinae, while the retinal image of an object that we follow with the eyes is approximately stationary. To enable us to perceive motion in

  8. Thermally stimulated discharge current (TSDC) and dielectric ...

    Indian Academy of Sciences (India)

    Unknown

    2001-10-09

    Oct 9, 2001 ... Measurements of TSDC and dielectric constant, ε′, have been ... Keywords. Semiconducting glass; TSDC; trap energy; dielectric constant. 1. ... determination of mean depth of the internal charge, activation ... thermal charging, viz. (i) internal ... the basis of d.c. conductivity and short range Na+ ion motion.

  9. Thermal process of an air column

    International Nuclear Information System (INIS)

    Lee, F.T.

    1994-01-01

    Thermal process of a hot air column is discussed based on laws of thermodynamics. The kinetic motion of the air mass in the column can be used as a power generator. Alternatively, the column can also function as a exhaust/cooler

  10. Solid state engine with alternating motion

    Science.gov (United States)

    Golestaneh, Ahmad A.

    1982-01-01

    Heat energy is converted to mechanical motion utilizing apparatus including a cylinder, a piston having openings therein reciprocable in the cylinder, inlet and outlet ports for warm water at one end of the cylinder, inlet and outlet ports for cool water at the other end of the cylinder, gates movable with the piston and slidably engaging the cylinder wall to alternately open and close the warm and cool water ports, a spring bearing against the warm water side of the piston and a double helix of a thermal shape memory material attached to the cool end of the cylinder and to the piston. The piston is caused to reciprocate by alternately admitting cool water and warm water to the cylinder.

  11. Thermal Properties and Thermal Analysis:

    Science.gov (United States)

    Kasap, Safa; Tonchev, Dan

    The chapter provides a summary of the fundamental concepts that are needed to understand the heat capacity C P, thermal conductivity κ, and thermal expansion coefficient α L of materials. The C P, κ, and α of various classes of materials, namely, semiconductors, polymers, and glasses, are reviewed, and various typical characteristics are summarized. A key concept in crystalline solids is the Debye theory of the heat capacity, which has been widely used for many decades for calculating the C P of crystals. The thermal properties are interrelated through Grüneisen's theorem. Various useful empirical rules for calculating C P and κ have been used, some of which are summarized. Conventional differential scanning calorimetry (DSC) is a powerful and convenient thermal analysis technique that allows various important physical and chemical transformations, such as the glass transition, crystallization, oxidation, melting etc. to be studied. DSC can also be used to obtain information on the kinetics of the transformations, and some of these thermal analysis techniques are summarized. Temperature-modulated DSC, TMDSC, is a relatively recent innovation in which the sample temperature is ramped slowly and, at the same time, sinusoidally modulated. TMDSC has a number of distinct advantages compared with the conventional DSC since it measures the complex heat capacity. For example, the glass-transition temperature T g measured by TMDSC has almost no dependence on the thermal history, and corresponds to an almost step life change in C P. The new Tzero DSC has an additional thermocouple to calibrate better for thermal lags inherent in the DSC measurement, and allows more accurate thermal analysis.

  12. Analytical Analysis of Motion Separability

    Directory of Open Access Journals (Sweden)

    Marjan Hadian Jazi

    2013-01-01

    Full Text Available Motion segmentation is an important task in computer vision and several practical approaches have already been developed. A common approach to motion segmentation is to use the optical flow and formulate the segmentation problem using a linear approximation of the brightness constancy constraints. Although there are numerous solutions to solve this problem and their accuracies and reliabilities have been studied, the exact definition of the segmentation problem, its theoretical feasibility and the conditions for successful motion segmentation are yet to be derived. This paper presents a simplified theoretical framework for the prediction of feasibility, of segmentation of a two-dimensional linear equation system. A statistical definition of a separable motion (structure is presented and a relatively straightforward criterion for predicting the separability of two different motions in this framework is derived. The applicability of the proposed criterion for prediction of the existence of multiple motions in practice is examined using both synthetic and real image sequences. The prescribed separability criterion is useful in designing computer vision applications as it is solely based on the amount of relative motion and the scale of measurement noise.

  13. Cervical spine motion: radiographic study

    International Nuclear Information System (INIS)

    Morgan, J.P.; Miyabayashi, T.; Choy, S.

    1986-01-01

    Knowledge of the acceptable range of motion of the cervical spine of the dog is used in the radiographic diagnosis of both developmental and degenerative diseases. A series of radiographs of mature Beagle dogs was used to identify motion within sagittal and transverse planes. Positioning of the dog's head and neck was standardized, using a restraining board, and mimicked those thought to be of value in diagnostic radiology. The range of motion was greatest between C2 and C5. Reports of severe disk degeneration in the cervical spine of the Beagle describe the most severely involved disks to be C4 through C7. Thus, a high range of motion between vertebral segments does not seem to be the cause for the severe degenerative disk disease. Dorsoventral slippage between vertebral segments was seen, but was not accurately measured. Wedging of disks was clearly identified. At the atlantoaxio-occipital region, there was a high degree of motion within the sagittal plane at the atlantoaxial and atlanto-occipital joints; the measurement can be a guideline in the radiographic diagnosis of instability due to developmental anomalies in this region. Lateral motion within the transverse plane was detected at the 2 joints; however, motion was minimal, and the measurements seemed to be less accurate because of rotation of the cervical spine. Height of the vertebral canal was consistently noted to be greater at the caudal orifice, giving some warning to the possibility of overdiagnosis in suspected instances of cervical spondylopathy

  14. Effects of quantum statistics of phonons on the thermal conductivity of silicon and germanium nanoribbons

    Science.gov (United States)

    Kosevich, Yuriy A.; Savin, Alexander V.; Cantarero, Andrés

    2013-01-01

    We present molecular dynamics simulation of phonon thermal conductivity of semiconductor nanoribbons with an account for phonon quantum statistics. In our semiquantum molecular dynamics simulation, dynamics of the system is described with the use of classical Newtonian equations of motion where the effect of phonon quantum statistics is introduced through random Langevin-like forces with a specific power spectral density (color noise). The color noise describes interaction of the molecular system with the thermostat. The thermal transport of silicon and germanium nanoribbons with atomically smooth (perfect) and rough (porous) edges are studied. We show that the existence of rough (porous) edges and the quantum statistics of phonon change drastically the low-temperature thermal conductivity of the nanoribbon in comparison with that of the perfect nanoribbon with atomically smooth edges and classical phonon dynamics and statistics. The rough-edge phonon scattering and weak anharmonicity of the considered lattice produce a weakly pronounced maximum of thermal conductivity of the nanoribbon at low temperature.

  15. Fundamentals - longitudinal motion

    International Nuclear Information System (INIS)

    Weng, W.T.

    1989-01-01

    There are many ways to accelerate charged particles to high energy for physics research. Each has served its purpose but eventually has encountered fundamental limitations of one kind or another. Looking at the famous Livingston curve, the initial birth and final level-off of all types of accelerators is seen. In fact, in the mid-80s we personally witnessed the creation of a new type of collider - the Stanford Linear Collider. Also witnessed, was the resurgence of study into novel methods of acceleration. This paper will cover acceleration and longitudinal motion in a synchrotron. A synchrotron is a circular accelerator with the following three characteristics: (1) Magnetic guiding (dipole) and confinement (quadrupole) components are placed in a small neighborhood around the equilibrium orbit. (2) Particles are kept in resonance with the radio-frequency electric field indefinitely to achieve acceleration to higher energies. (3) Magnetic fields are varied adiabatically with the energy of the particle. D. Edwards described the transverse oscillations of particles in a synchrotron. Here the author talks about the longitudinal oscillations of particles. The phase stability principle was invented by V. Veksler and E. McMillan independently in 1945. The phase stability and strong focusing principle, invented by Courant and Livingston in 1952, enabled the steady energy gain of accelerators and storage rings witnessed during the past 30 years. This paper is a unified overview of the related rf subjects in an accelerator and a close coupling between accelerator physics and engineering practices, which is essential for the major progress in areas such as high intensity synchrotrons, a multistage accelerator complex, and anti-proton production and cooling, made possible in the past 20 years

  16. A Motion Planning Approach to Studying Molecular Motions

    KAUST Repository

    Amato, Nancy M.; Tapia, Lydia; Thomas, Shawna

    2010-01-01

    While structurally very different, protein and RNA molecules share an important attribute. The motions they undergo are strongly related to the function they perform. For example, many diseases such as Mad Cow disease or Alzheimer's disease

  17. What motion is: William Neile and the laws of motion.

    Science.gov (United States)

    Kemeny, Max

    2017-07-01

    In 1668-1669 William Neile and John Wallis engaged in a protracted correspondence regarding the nature of motion. Neile was unhappy with the laws of motion that had been established by the Royal Society in three papers published in 1668, deeming them not explanations of motion at all, but mere descriptions. Neile insisted that science could not be informative without a discussion of causes, meaning that Wallis's purely kinematic account of collision could not be complete. Wallis, however, did not consider Neile's objections to his work to be serious. Rather than engage in a discussion of the proper place of natural philosophy in science, Wallis decided to show how Neile's preferred treatment of motion lead to absurd conclusions. This dispute is offered as a case study of dispute resolution within the early Royal Society.

  18. Nonlinear optomechanical measurement of mechanical motion

    DEFF Research Database (Denmark)

    Brawley, G.A.; Vanner, M R; Larsen, Peter Emil

    2016-01-01

    Precision measurement of nonlinear observables is an important goal in all facets of quantum optics. This allows measurement-based non-classical state preparation, which has been applied to great success in various physical systems, and provides a route for quantum information processing with oth......Precision measurement of nonlinear observables is an important goal in all facets of quantum optics. This allows measurement-based non-classical state preparation, which has been applied to great success in various physical systems, and provides a route for quantum information processing...... with otherwise linear interactions. In cavity optomechanics much progress has been made using linear interactions and measurement, but observation of nonlinear mechanical degrees-of-freedom remains outstanding. Here we report the observation of displacement-squared thermal motion of a micro-mechanical resonator...... by exploiting the intrinsic nonlinearity of the radiation-pressure interaction. Using this measurement we generate bimodal mechanical states of motion with separations and feature sizes well below 100 pm. Future improvements to this approach will allow the preparation of quantum superposition states, which can...

  19. Algebraic motion of vertically displacing plasmas

    Science.gov (United States)

    Pfefferlé, D.; Bhattacharjee, A.

    2018-02-01

    The vertical motion of a tokamak plasma is analytically modelled during its non-linear phase by a free-moving current-carrying rod inductively coupled to a set of fixed conducting wires or a cylindrical conducting shell. The solutions capture the leading term in a Taylor expansion of the Green's function for the interaction between the plasma column and the surrounding vacuum vessel. The plasma shape and profiles are assumed not to vary during the vertical drifting phase such that the plasma column behaves as a rigid body. In the limit of perfectly conducting structures, the plasma is prevented to come in contact with the wall due to steep effective potential barriers created by the induced Eddy currents. Resistivity in the wall allows the equilibrium point to drift towards the vessel on the slow timescale of flux penetration. The initial exponential motion of the plasma, understood as a resistive vertical instability, is succeeded by a non-linear "sinking" behaviour shown to be algebraic and decelerating. The acceleration of the plasma column often observed in experiments is thus concluded to originate from an early sharing of toroidal current between the core, the halo plasma, and the wall or from the thermal quench dynamics precipitating loss of plasma current.

  20. Velocity navigator for motion compensated thermometry.

    Science.gov (United States)

    Maier, Florian; Krafft, Axel J; Yung, Joshua P; Stafford, R Jason; Elliott, Andrew; Dillmann, Rüdiger; Semmler, Wolfhard; Bock, Michael

    2012-02-01

    Proton resonance frequency shift thermometry is sensitive to breathing motion that leads to incorrect phase differences. In this work, a novel velocity-sensitive navigator technique for triggering MR thermometry image acquisition is presented. A segmented echo planar imaging pulse sequence was modified for velocity-triggered temperature mapping. Trigger events were generated when the estimated velocity value was less than 0.2 cm/s during the slowdown phase in parallel to the velocity-encoding direction. To remove remaining high-frequency spikes from pulsation in real time, a Kalman filter was applied to the velocity navigator data. A phantom experiment with heating and an initial volunteer experiment without heating were performed to show the applicability of this technique. Additionally, a breath-hold experiment was conducted for comparison. A temperature rise of ΔT = +37.3°C was seen in the phantom experiment, and a root mean square error (RMSE) outside the heated region of 2.3°C could be obtained for periodic motion. In the volunteer experiment, a RMSE of 2.7°C/2.9°C (triggered vs. breath hold) was measured. A novel velocity navigator with Kalman filter postprocessing in real time significantly improves the temperature accuracy over non-triggered acquisitions and suggests being comparable to a breath-held acquisition. The proposed technique might be clinically applied for monitoring of thermal ablations in abdominal organs.

  1. Macroscopic dynamics of thermal nuclear excitations

    International Nuclear Information System (INIS)

    Bastrukov, S.I.; Deak, F.; Kiss, A.; Seres, Z.

    1989-11-01

    The concept of kinetic temperature as a local dynamical variable of thermal nuclear collective motion is formulated using long-mean-free-path approach based on the Landau-Vlasov kinetic equation. In the Fermi drop model the thermal fluid dynamics of the spherical nucleus is analyzed. It is shown that in a compressible Fermi liquid the temperature pulses propagate in the form of spherical wave in phase with the acoustic wave. The thermal and compressional excitations are caused by the isotropic harmonic oscillations of the Fermi sphere in momentum space. (author) 25 refs.; 2 figs

  2. Adaptive Motion Compensation in Radiotherapy

    CERN Document Server

    Murphy, Martin J

    2011-01-01

    External-beam radiotherapy has long been challenged by the simple fact that patients can (and do) move during the delivery of radiation. Recent advances in imaging and beam delivery technologies have made the solution--adapting delivery to natural movement--a practical reality. Adaptive Motion Compensation in Radiotherapy provides the first detailed treatment of online interventional techniques for motion compensation radiotherapy. This authoritative book discusses: Each of the contributing elements of a motion-adaptive system, including target detection and tracking, beam adaptation, and pati

  3. Scaling earthquake ground motions for performance-based assessment of buildings

    Science.gov (United States)

    Huang, Y.-N.; Whittaker, A.S.; Luco, N.; Hamburger, R.O.

    2011-01-01

    The impact of alternate ground-motion scaling procedures on the distribution of displacement responses in simplified structural systems is investigated. Recommendations are provided for selecting and scaling ground motions for performance-based assessment of buildings. Four scaling methods are studied, namely, (1)geometric-mean scaling of pairs of ground motions, (2)spectrum matching of ground motions, (3)first-mode-period scaling to a target spectral acceleration, and (4)scaling of ground motions per the distribution of spectral demands. Data were developed by nonlinear response-history analysis of a large family of nonlinear single degree-of-freedom (SDOF) oscillators that could represent fixed-base and base-isolated structures. The advantages and disadvantages of each scaling method are discussed. The relationship between spectral shape and a ground-motion randomness parameter, is presented. A scaling procedure that explicitly considers spectral shape is proposed. ?? 2011 American Society of Civil Engineers.

  4. Thermal comfort

    DEFF Research Database (Denmark)

    d’Ambrosio Alfano, Francesca Romana; Olesen, Bjarne W.; Palella, Boris Igor

    2014-01-01

    Thermal comfort is one of the most important aspects of the indoor environmental quality due to its effects on well-being, people's performance and building energy requirements. Its attainment is not an easy task requiring advanced design and operation of building and HVAC systems, taking...... into account all parameters involved. Even though thermal comfort fundamentals are consolidated topics for more than forty years, often designers seem to ignore or apply them in a wrong way. Design input values from standards are often considered as universal values rather than recommended values to be used...... under specific conditions. At operation level, only few variables are taken into account with unpredictable effects on the assessment of comfort indices. In this paper, the main criteria for the design and assessment of thermal comfort are discussed in order to help building and HVAC systems designers...

  5. Robust motion estimation using connected operators

    OpenAIRE

    Salembier Clairon, Philippe Jean; Sanson, H

    1997-01-01

    This paper discusses the use of connected operators for robust motion estimation The proposed strategy involves a motion estimation step extracting the dominant motion and a ltering step relying on connected operators that remove objects that do not fol low the dominant motion. These two steps are iterated in order to obtain an accurate motion estimation and a precise de nition of the objects fol lowing this motion This strategy can be applied on the entire frame or on individual connected c...

  6. Quantum signature of chaos and thermalization in the kicked Dicke model

    Science.gov (United States)

    Ray, S.; Ghosh, A.; Sinha, S.

    2016-09-01

    We study the quantum dynamics of the kicked Dicke model (KDM) in terms of the Floquet operator, and we analyze the connection between chaos and thermalization in this context. The Hamiltonian map is constructed by suitably taking the classical limit of the Heisenberg equation of motion to study the corresponding phase-space dynamics, which shows a crossover from regular to chaotic motion by tuning the kicking strength. The fixed-point analysis and calculation of the Lyapunov exponent (LE) provide us with a complete picture of the onset of chaos in phase-space dynamics. We carry out a spectral analysis of the Floquet operator, which includes a calculation of the quasienergy spacing distribution and structural entropy to show the correspondence to the random matrix theory in the chaotic regime. Finally, we analyze the thermodynamics and statistical properties of the bosonic sector as well as the spin sector, and we discuss how such a periodically kicked system relaxes to a thermalized state in accordance with the laws of statistical mechanics.

  7. Deterministic Brownian motion generated from differential delay equations.

    Science.gov (United States)

    Lei, Jinzhi; Mackey, Michael C

    2011-10-01

    This paper addresses the question of how Brownian-like motion can arise from the solution of a deterministic differential delay equation. To study this we analytically study the bifurcation properties of an apparently simple differential delay equation and then numerically investigate the probabilistic properties of chaotic solutions of the same equation. Our results show that solutions of the deterministic equation with randomly selected initial conditions display a Gaussian-like density for long time, but the densities are supported on an interval of finite measure. Using these chaotic solutions as velocities, we are able to produce Brownian-like motions, which show statistical properties akin to those of a classical Brownian motion over both short and long time scales. Several conjectures are formulated for the probabilistic properties of the solution of the differential delay equation. Numerical studies suggest that these conjectures could be "universal" for similar types of "chaotic" dynamics, but we have been unable to prove this.

  8. Matrix thermalization

    International Nuclear Information System (INIS)

    Craps, Ben; Evnin, Oleg; Nguyen, Kévin

    2017-01-01

    Matrix quantum mechanics offers an attractive environment for discussing gravitational holography, in which both sides of the holographic duality are well-defined. Similarly to higher-dimensional implementations of holography, collapsing shell solutions in the gravitational bulk correspond in this setting to thermalization processes in the dual quantum mechanical theory. We construct an explicit, fully nonlinear supergravity solution describing a generic collapsing dilaton shell, specify the holographic renormalization prescriptions necessary for computing the relevant boundary observables, and apply them to evaluating thermalizing two-point correlation functions in the dual matrix theory.

  9. Matrix thermalization

    Science.gov (United States)

    Craps, Ben; Evnin, Oleg; Nguyen, Kévin

    2017-02-01

    Matrix quantum mechanics offers an attractive environment for discussing gravitational holography, in which both sides of the holographic duality are well-defined. Similarly to higher-dimensional implementations of holography, collapsing shell solutions in the gravitational bulk correspond in this setting to thermalization processes in the dual quantum mechanical theory. We construct an explicit, fully nonlinear supergravity solution describing a generic collapsing dilaton shell, specify the holographic renormalization prescriptions necessary for computing the relevant boundary observables, and apply them to evaluating thermalizing two-point correlation functions in the dual matrix theory.

  10. Matrix thermalization

    Energy Technology Data Exchange (ETDEWEB)

    Craps, Ben [Theoretische Natuurkunde, Vrije Universiteit Brussel (VUB), and International Solvay Institutes, Pleinlaan 2, B-1050 Brussels (Belgium); Evnin, Oleg [Department of Physics, Faculty of Science, Chulalongkorn University, Thanon Phayathai, Pathumwan, Bangkok 10330 (Thailand); Theoretische Natuurkunde, Vrije Universiteit Brussel (VUB), and International Solvay Institutes, Pleinlaan 2, B-1050 Brussels (Belgium); Nguyen, Kévin [Theoretische Natuurkunde, Vrije Universiteit Brussel (VUB), and International Solvay Institutes, Pleinlaan 2, B-1050 Brussels (Belgium)

    2017-02-08

    Matrix quantum mechanics offers an attractive environment for discussing gravitational holography, in which both sides of the holographic duality are well-defined. Similarly to higher-dimensional implementations of holography, collapsing shell solutions in the gravitational bulk correspond in this setting to thermalization processes in the dual quantum mechanical theory. We construct an explicit, fully nonlinear supergravity solution describing a generic collapsing dilaton shell, specify the holographic renormalization prescriptions necessary for computing the relevant boundary observables, and apply them to evaluating thermalizing two-point correlation functions in the dual matrix theory.

  11. Dance notations and robot motion

    CERN Document Server

    Abe, Naoko

    2016-01-01

    How and why to write a movement? Who is the writer? Who is the reader? They may be choreographers working with dancers. They may be roboticists programming robots. They may be artists designing cartoons in computer animation. In all such fields the purpose is to express an intention about a dance, a specific motion or an action to perform, in terms of intelligible sequences of elementary movements, as a music score that would be devoted to motion representation. Unfortunately there is no universal language to write a motion. Motion languages live together in a Babel tower populated by biomechanists, dance notators, neuroscientists, computer scientists, choreographers, roboticists. Each community handles its own concepts and speaks its own language. The book accounts for this diversity. Its origin is a unique workshop held at LAAS-CNRS in Toulouse in 2014. Worldwide representatives of various communities met there. Their challenge was to reach a mutual understanding allowing a choreographer to access robotics ...

  12. Generalized quantal equation of motion

    International Nuclear Information System (INIS)

    Morsy, M.W.; Embaby, M.

    1986-07-01

    In the present paper, an attempt is made for establishing a generalized equation of motion for quantal objects, in which intrinsic self adjointness is naturally built in, independently of any prescribed representation. This is accomplished by adopting Hamilton's principle of least action, after incorporating, properly, the quantal features and employing the generalized calculus of variations, without being restricted to fixed end points representation. It turns out that our proposed equation of motion is an intrinsically self-adjoint Euler-Lagrange's differential equation that ensures extremization of the quantal action as required by Hamilton's principle. Time dependence is introduced and the corresponding equation of motion is derived, in which intrinsic self adjointness is also achieved. Reducibility of the proposed equation of motion to the conventional Schroedinger equation is examined. The corresponding continuity equation is established, and both of the probability density and the probability current density are identified. (author)

  13. On the equations of motion

    International Nuclear Information System (INIS)

    Jannussis, A.; Streclas, A.; Sourlas, D.; Vlachos, K.

    1977-01-01

    Using the theorem of the derivative of a function of operators with respect to any parameter, we can find the equation of motion of a system in classical mechanics, in canonical as well as in non-canonical mechanics

  14. Weigh-in-Motion Stations

    Data.gov (United States)

    Department of Homeland Security — The data included in the GIS Traffic Stations Version database have been assimilated from station description files provided by FHWA for Weigh-in-Motion (WIM), and...

  15. Physical chemistry: Molecular motion watched

    Science.gov (United States)

    Siwick, Bradley; Collet, Eric

    2013-04-01

    A laser pulse can switch certain crystals from an insulating phase to a highly conducting phase. The ultrafast molecular motions that drive the transition have been directly observed using electron diffraction. See Letter p.343

  16. Is Diaphragm Motion a Good Surrogate for Liver Tumor Motion?

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Juan [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); School of Information Science and Engineering, Shandong University, Jinan, Shandong (China); Cai, Jing [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Wang, Hongjun [School of Information Science and Engineering, Shandong University, Jinan, Shandong (China); Chang, Zheng; Czito, Brian G. [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Bashir, Mustafa R. [Department of Radiology, Duke University Medical Center, Durham, North Carolina (United States); Palta, Manisha [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Yin, Fang-Fang, E-mail: fangfang.yin@duke.edu [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States)

    2014-11-15

    Purpose: To evaluate the relationship between liver tumor motion and diaphragm motion. Methods and Materials: Fourteen patients with hepatocellular carcinoma (10 of 14) or liver metastases (4 of 14) undergoing radiation therapy were included in this study. All patients underwent single-slice cine–magnetic resonance imaging simulations across the center of the tumor in 3 orthogonal planes. Tumor and diaphragm motion trajectories in the superior–inferior (SI), anterior–posterior (AP), and medial–lateral (ML) directions were obtained using an in-house-developed normalized cross-correlation–based tracking technique. Agreement between the tumor and diaphragm motion was assessed by calculating phase difference percentage, intraclass correlation coefficient, and Bland-Altman analysis (Diff). The distance between the tumor and tracked diaphragm area was analyzed to understand its impact on the correlation between the 2 motions. Results: Of all patients, the mean (±standard deviation) phase difference percentage values were 7.1% ± 1.1%, 4.5% ± 0.5%, and 17.5% ± 4.5% in the SI, AP, and ML directions, respectively. The mean intraclass correlation coefficient values were 0.98 ± 0.02, 0.97 ± 0.02, and 0.08 ± 0.06 in the SI, AP, and ML directions, respectively. The mean Diff values were 2.8 ± 1.4 mm, 2.4 ± 1.1 mm, and 2.2 ± 0.5 mm in the SI, AP, and ML directions, respectively. Tumor and diaphragm motions had high concordance when the distance between the tumor and tracked diaphragm area was small. Conclusions: This study showed that liver tumor motion had good correlation with diaphragm motion in the SI and AP directions, indicating diaphragm motion in the SI and AP directions could potentially be used as a reliable surrogate for liver tumor motion.

  17. Storyboard dalam Pembuatan Motion Graphic

    OpenAIRE

    Satrya Mahardhika; A.F. Choiril Anam Fathoni

    2013-01-01

    Motion graphics is one category in the animation that makes animation with lots of design elements in each component. Motion graphics needs long process including preproduction, production, and postproduction. Preproduction has an important role so that the next stage may provide guidance or instructions for the production process or the animation process. Preproduction includes research, making the story, script, screenplay, character, environment design and storyboards. The storyboard will ...

  18. q-deformed Brownian motion

    CERN Document Server

    Man'ko, V I

    1993-01-01

    Brownian motion may be embedded in the Fock space of bosonic free field in one dimension.Extending this correspondence to a family of creation and annihilation operators satisfying a q-deformed algebra, the notion of q-deformation is carried from the algebra to the domain of stochastic processes.The properties of q-deformed Brownian motion, in particular its non-Gaussian nature and cumulant structure,are established.

  19. Latent stereopsis for motion in depth in strabismic amblyopia.

    Science.gov (United States)

    Hess, Robert F; Mansouri, Behzad; Thompson, Benjamin; Gheorghiu, Elena

    2009-10-01

    To investigate the residual stereo function of a group of 15 patients with strabismic amblyopia, by using motion-in-depth stimuli that allow discrimination of contributions from local disparity as opposed to those from local velocity mechanisms as a function of the rate of depth change. The stereo performance (percentage correct) was measured as a function of the rate of depth change for dynamic random dot stimuli that were either temporally correlated or uncorrelated. Residual stereoscopic function was demonstrated for motion in depth based on local disparity information in 2 of the 15 observers with strabismic amblyopia. The use of a neutral-density (ND) filter in front of the fixing eye enhanced motion-in-depth performance in four subjects randomly selected from the group that originally displayed only chance performance. This finding was true across temporal rate and for correlated and uncorrelated stimuli, suggesting that it was disparity based. The opposite occurred in a group of normal subjects. In a separate experiment, the hypothesis was that the beneficial effect of the ND filter is due to its contrast and/or mean luminance-reducing effects rather than any interocular time delay that it may introduce and that it is specific to motion-in-depth performance, as similar improvements were not found for static stereopsis. A small proportion of observers with strabismic amblyopia exhibit residual performance for motion in depth, and it is disparity based. Furthermore, some observers with strabismic amblyopia who do not display any significant stereo performance for motion in depth under normal binocular viewing may display above-chance stereo performance if the degree of interocular suppression is reduced. The authors term this phenomenon latent stereopsis.

  20. Collective cell motion in endothelial monolayers

    International Nuclear Information System (INIS)

    Szabó, A; Ünnep, R; Méhes, E; Czirók, A; Twal, W O; Argraves, W S; Cao, Y

    2010-01-01

    Collective cell motility is an important aspect of several developmental and pathophysiological processes. Despite its importance, the mechanisms that allow cells to be both motile and adhere to one another are poorly understood. In this study we establish statistical properties of the random streaming behavior of endothelial monolayer cultures. To understand the reported empirical findings, we expand the widely used cellular Potts model to include active cell motility. For spontaneous directed motility we assume a positive feedback between cell displacements and cell polarity. The resulting model is studied with computer simulations and is shown to exhibit behavior compatible with experimental findings. In particular, in monolayer cultures both the speed and persistence of cell motion decreases, transient cell chains move together as groups and velocity correlations extend over several cell diameters. As active cell motility is ubiquitous both in vitro and in vivo, our model is expected to be a generally applicable representation of cellular behavior

  1. Passive infrared motion sensing technology

    International Nuclear Information System (INIS)

    Doctor, A.P.

    1994-01-01

    In the last 10 years passive IR based (8--12 microns) motion sensing has matured to become the dominant method of volumetric space protection and surveillance. These systems currently cost less than $25 to produce and yet use traditionally expensive IR optics, filters, sensors and electronic circuitry. This IR application is quite interesting in that the volumes of systems produced and the costs and performance level required prove that there is potential for large scale commercial applications of IR technology. This paper will develop the basis and principles of operation of a staring motion sensor system using a technical approach. A model for the motion of the target is developed and compared to the background. The IR power difference between the target and the background as well as the optical requirements are determined from basic principles and used to determine the performance of the system. Low cost reflective and refractive IR optics and bandpass IR filters are discussed. The pyroelectric IR detector commonly used is fully discussed and characterized. Various schemes for ''false alarms'' have been developed and are also explained. This technology is also used in passive IR based motion sensors for other applications such as lighting control. These applications are also discussed. In addition the paper will discuss new developments in IR surveillance technology such as the use of linear motion sensing arrays. This presentation can be considered a ''primer'' on the art of Passive IR Motion Sensing as applied to Surveillance Technology

  2. Research progress of the static and dynamic characteristics and motion errors of hydrostatic supports

    Directory of Open Access Journals (Sweden)

    Zhiwei WANG

    2016-06-01

    Full Text Available At present, the research on static and dynamic characteristics of hydrostatic supports depend on the form and structure of the restrictor, which are mainly focused on the influences of recess shape, bearing structure, bearing surface roughness, lubricant and elastic deformations of the bearing. There are few studies on the thermal effect of hydrostatic supports and static and dynamic characteristics of hydrostatic guideways. The research on motion errors of hydrostatic supports is primarily based on the static equilibrium of the moving part. The effects of the motion speed of the moving part and structural deformation on the motion errors are not considered. Finally, the research prospects from the standardization, modularization and industrialization of hydrostatic supports, thermal effect of hydrostatic bearing, the static and dynamic characteristics of hydrostatic guideways and motion errors of hydrostatic supports under operating conditions are concluded.

  3. Seismic Excitation of the Polar Motion

    Science.gov (United States)

    Chao, Benjamin Fong; Gross, Richard S.; Han, Yan-Ben

    1996-01-01

    The mass redistribution in the earth as a result of an earthquake faulting changes the earth's inertia tensor, and hence its rotation. Using the complete formulae developed by Chao and Gross (1987) based on the normal mode theory, we calculated the earthquake-induced polar motion excitation for the largest 11,015 earthquakes that occurred during 1977.0-1993.6. The seismic excitations in this period are found to be two orders of magnitude below the detection threshold even with today's high precision earth rotation measurements. However, it was calculated that an earthquake of only one tenth the size of the great 1960 Chile event, if happened today, could be comfortably detected in polar motion observations. Furthermore, collectively these seismic excitations have a strong statistical tendency to nudge the pole towards approx. 140 deg E, away from the actually observed polar drift direction. This non-random behavior, similarly found in other earthquake-induced changes in earth rotation and low-degree gravitational field by Chao and Gross (1987), manifests some geodynamic behavior yet to be explored.

  4. A scalable distributed RRT for motion planning

    KAUST Repository

    Jacobs, Sam Ade

    2013-05-01

    Rapidly-exploring Random Tree (RRT), like other sampling-based motion planning methods, has been very successful in solving motion planning problems. Even so, sampling-based planners cannot solve all problems of interest efficiently, so attention is increasingly turning to parallelizing them. However, one challenge in parallelizing RRT is the global computation and communication overhead of nearest neighbor search, a key operation in RRTs. This is a critical issue as it limits the scalability of previous algorithms. We present two parallel algorithms to address this problem. The first algorithm extends existing work by introducing a parameter that adjusts how much local computation is done before a global update. The second algorithm radially subdivides the configuration space into regions, constructs a portion of the tree in each region in parallel, and connects the subtrees,i removing cycles if they exist. By subdividing the space, we increase computation locality enabling a scalable result. We show that our approaches are scalable. We present results demonstrating almost linear scaling to hundreds of processors on a Linux cluster and a Cray XE6 machine. © 2013 IEEE.

  5. A scalable distributed RRT for motion planning

    KAUST Repository

    Jacobs, Sam Ade; Stradford, Nicholas; Rodriguez, Cesar; Thomas, Shawna; Amato, Nancy M.

    2013-01-01

    Rapidly-exploring Random Tree (RRT), like other sampling-based motion planning methods, has been very successful in solving motion planning problems. Even so, sampling-based planners cannot solve all problems of interest efficiently, so attention is increasingly turning to parallelizing them. However, one challenge in parallelizing RRT is the global computation and communication overhead of nearest neighbor search, a key operation in RRTs. This is a critical issue as it limits the scalability of previous algorithms. We present two parallel algorithms to address this problem. The first algorithm extends existing work by introducing a parameter that adjusts how much local computation is done before a global update. The second algorithm radially subdivides the configuration space into regions, constructs a portion of the tree in each region in parallel, and connects the subtrees,i removing cycles if they exist. By subdividing the space, we increase computation locality enabling a scalable result. We show that our approaches are scalable. We present results demonstrating almost linear scaling to hundreds of processors on a Linux cluster and a Cray XE6 machine. © 2013 IEEE.

  6. Indeterminism in Classical Dynamics of Particle Motion

    Science.gov (United States)

    Eyink, Gregory; Vishniac, Ethan; Lalescu, Cristian; Aluie, Hussein; Kanov, Kalin; Burns, Randal; Meneveau, Charles; Szalay, Alex

    2013-03-01

    We show that ``God plays dice'' not only in quantum mechanics but also in the classical dynamics of particles advected by turbulent fluids. With a fixed deterministic flow velocity and an exactly known initial position, the particle motion is nevertheless completely unpredictable! In analogy with spontaneous magnetization in ferromagnets which persists as external field is taken to zero, the particle trajectories in turbulent flow remain random as external noise vanishes. The necessary ingredient is a rough advecting field with a power-law energy spectrum extending to smaller scales as noise is taken to zero. The physical mechanism of ``spontaneous stochasticity'' is the explosive dispersion of particle pairs proposed by L. F. Richardson in 1926, so the phenomenon should be observable in laboratory and natural turbulent flows. We present here the first empirical corroboration of these effects in high Reynolds-number numerical simulations of hydrodynamic and magnetohydrodynamic fluid turbulence. Since power-law spectra are seen in many other systems in condensed matter, geophysics and astrophysics, the phenomenon should occur rather widely. Fast reconnection in solar flares and other astrophysical systems can be explained by spontaneous stochasticity of magnetic field-line motion

  7. Audiovisual associations alter the perception of low-level visual motion

    Directory of Open Access Journals (Sweden)

    Hulusi eKafaligonul

    2015-03-01

    Full Text Available Motion perception is a pervasive nature of vision and is affected by both immediate pattern of sensory inputs and prior experiences acquired through associations. Recently, several studies reported that an association can be established quickly between directions of visual motion and static sounds of distinct frequencies. After the association is formed, sounds are able to change the perceived direction of visual motion. To determine whether such rapidly acquired audiovisual associations and their subsequent influences on visual motion perception are dependent on the involvement of higher-order attentive tracking mechanisms, we designed psychophysical experiments using regular and reverse-phi random dot motions isolating low-level pre-attentive motion processing. Our results show that an association between the directions of low-level visual motion and static sounds can be formed and this audiovisual association alters the subsequent perception of low-level visual motion. These findings support the view that audiovisual associations are not restricted to high-level attention based motion system and early-level visual motion processing has some potential role.

  8. [Temporal Analysis of Body Sway during Reciprocator Motion Movie Viewing].

    Science.gov (United States)

    Sugiura, Akihiro; Tanaka, Kunihiko; Wakatabe, Shun; Matsumoto, Chika; Miyao, Masaru

    2016-01-01

    We aimed to investigate the effect of stereoscopic viewing and the degree of awareness of motion sickness on posture by measuring body sway during motion movie viewing. Nineteen students (12 men and 7 women; age range, 21-24 years) participated in this study. The movie, which showed several balls randomly positioned, was projected on a white wall 2 m in front of the subjects through a two-dimensional (2-D)/three-dimensional (3-D) convertible projector. To measure body sway during movie viewing, the subjects stood statically erect on a Wii balance board, with the toe opening at 18 degrees. The study protocol was as follows: The subjects watched (1) a nonmoving movie for 1 minute as the pretest and then (2) a round-trip sinusoidally moving-in-depth-direction movie for 3 minutes. (3) The initial static movie was shown again for 1 minute. Steps (2) and (3) were treated as one trial, after which two trials (2-D and 3-D movies) were performed in a random sequence. In this study, we found that posture changed according to the motion in the movie and that the longer the viewing time, the higher the synchronization accuracy. These tendencies depended on the level of awareness of motion sickness or the 3-D movie viewed. The mechanism of postural change in movie viewing was not vection but self-defense to resolve sensory conflict between visual information (spatial swing) and equilibrium sense (motionlessness).

  9. Designing a compact MRI motion phantom

    Directory of Open Access Journals (Sweden)

    Schmiedel Max

    2016-09-01

    Full Text Available Even today, dealing with motion artifacts in magnetic resonance imaging (MRI is a challenging task. Image corruption due to spontaneous body motion complicates diagnosis. In this work, an MRI phantom for rigid motion is presented. It is used to generate motion-corrupted data, which can serve for evaluation of blind motion compensation algorithms. In contrast to commercially available MRI motion phantoms, the presented setup works on small animal MRI systems. Furthermore, retrospective gating is performed on the data, which can be used as a reference for novel motion compensation approaches. The motion of the signal source can be reconstructed using motor trigger signals and be utilized as the ground truth for motion estimation. The proposed setup results in motion corrected images. Moreover, the importance of preprocessing the MRI raw data, e.g. phase-drift correction, is demonstrated. The gained knowledge can be used to design an MRI phantom for elastic motion.

  10. Random magnetism

    International Nuclear Information System (INIS)

    Tsallis, C.

    1980-03-01

    The 'ingredients' which control a phase transition in well defined system as well as in random ones (e.g. random magnetic systems) are listed and discussed within a somehow unifying perspective. Among these 'ingredients' we find the couplings and elements responsible for the cooperative phenomenon, the topological connectivity as well as possible topological incompatibilities, the influence of new degrees of freedom, the order parameter dimensionality, the ground state degeneracy and finally the 'quanticity' of the system. The general trends, though illustrated in magnetic systems, essentially hold for all phase transitions, and give a basis for connection of this area with Field theory, Theory of dynamical systems, etc. (Author) [pt

  11. Random magnetism

    International Nuclear Information System (INIS)

    Tsallis, C.

    1981-01-01

    The 'ingredients' which control a phase transition in well defined systems as well as in random ones (e.q. random magnetic systems) are listed and discussed within a somehow unifying perspective. Among these 'ingredients' the couplings and elements responsible for the cooperative phenomenon, the topological connectivity as well as possible topological incompatibilities, the influence of new degrees of freedom, the order parameter dimensionality, the ground state degeneracy and finally the 'quanticity' of the system are found. The general trends, though illustrated in magnetic systems, essentially hold for all phase transitions, and give a basis for connection of this area with Field theory, Theory of dynamical systems, etc. (Author) [pt

  12. New methods for simulation of fractional Brownian motion

    International Nuclear Information System (INIS)

    Yin, Z.M.

    1996-01-01

    We present new algorithms for simulation of fractional Brownian motion (fBm) which comprises a set of important random functions widely used in geophysical and physical modeling, fractal image (landscape) simulating, and signal processing. The new algorithms, which are both accurate and efficient, allow us to generate not only a one-dimensional fBm process, but also two- and three-dimensional fBm fields. 23 refs., 3 figs

  13. Random paths with curvature dependent action

    International Nuclear Information System (INIS)

    Ambjoern, J.; Durhuus, B.

    1986-11-01

    We study discretized random paths with a curvature dependent action. The scaling limits of the corresponding statistical mechanical models can be constructed explicitly and are either usual Brownian motion or a theory where the correlations of tangents are nonzero and described by diffusion on the unit sphere. In the latter case the two point function has an anomalous dimension η = 1. (orig.)

  14. Study on convective mixing for thermal striping phenomena. Thermal-hydraulic analyses on mixing process in parallel triple-jet and comparisons between numerical methods

    International Nuclear Information System (INIS)

    Kimura, Nobuyuki; Nishimura, Motohiko; Kamide, Hideki

    2000-03-01

    A quantitative evaluation on thermal striping, in which temperature fluctuation due to convective mixing among jets imposes thermal fatigue on structural components, is of importance for reactor safety. In the present study, a water experiment was performed on parallel triple-jet: cold jet at the center and hot jets in both sides. Three kinds of numerical analyses based on the finite difference method were carried out to compare the similarity with the experiment by use of respective different handling of turbulence such as a k-ε two equation turbulence model (k-ε Model), a low Reynolds number stress and heat flux equation model (LRSFM) and a direct numerical simulation (DNS). In the experiment, the jets were mainly mixed due to the coherent oscillation. The numerical result using k-ε Model could not reproduce the coherent oscillating motion of jets due to rolling-up fluid. The oscillations of the jets predicted by LRSFM and DNS were in good agreements with the experiment. The comparison between the coherent and random components in experimental temperature fluctuation obtained by using the phase-averaging shows that k-ε Model and LRSFM overestimated the random component and the coherent component respectively. The ratios of coherent to random components in total temperature fluctuation obtained from DNS were in good agreements with the experiment. The numerical analysis using DNS can reproduce the coherent oscillation of the jets and the coherent / random components in temperature fluctuation. The analysis using LRSFM could simulate the mixing process of the jets with the low frequency. (author)

  15. Rapid sampling of molecular motions with prior information constraints.

    Science.gov (United States)

    Raveh, Barak; Enosh, Angela; Schueler-Furman, Ora; Halperin, Dan

    2009-02-01

    Proteins are active, flexible machines that perform a range of different functions. Innovative experimental approaches may now provide limited partial information about conformational changes along motion pathways of proteins. There is therefore a need for computational approaches that can efficiently incorporate prior information into motion prediction schemes. In this paper, we present PathRover, a general setup designed for the integration of prior information into the motion planning algorithm of rapidly exploring random trees (RRT). Each suggested motion pathway comprises a sequence of low-energy clash-free conformations that satisfy an arbitrary number of prior information constraints. These constraints can be derived from experimental data or from expert intuition about the motion. The incorporation of prior information is very straightforward and significantly narrows down the vast search in the typically high-dimensional conformational space, leading to dramatic reduction in running time. To allow the use of state-of-the-art energy functions and conformational sampling, we have integrated this framework into Rosetta, an accurate protocol for diverse types of structural modeling. The suggested framework can serve as an effective complementary tool for molecular dynamics, Normal Mode Analysis, and other prevalent techniques for predicting motion in proteins. We applied our framework to three different model systems. We show that a limited set of experimentally motivated constraints may effectively bias the simulations toward diverse predicates in an outright fashion, from distance constraints to enforcement of loop closure. In particular, our analysis sheds light on mechanisms of protein domain swapping and on the role of different residues in the motion.

  16. Rapid sampling of molecular motions with prior information constraints.

    Directory of Open Access Journals (Sweden)

    Barak Raveh

    2009-02-01

    Full Text Available Proteins are active, flexible machines that perform a range of different functions. Innovative experimental approaches may now provide limited partial information about conformational changes along motion pathways of proteins. There is therefore a need for computational approaches that can efficiently incorporate prior information into motion prediction schemes. In this paper, we present PathRover, a general setup designed for the integration of prior information into the motion planning algorithm of rapidly exploring random trees (RRT. Each suggested motion pathway comprises a sequence of low-energy clash-free conformations that satisfy an arbitrary number of prior information constraints. These constraints can be derived from experimental data or from expert intuition about the motion. The incorporation of prior information is very straightforward and significantly narrows down the vast search in the typically high-dimensional conformational space, leading to dramatic reduction in running time. To allow the use of state-of-the-art energy functions and conformational sampling, we have integrated this framework into Rosetta, an accurate protocol for diverse types of structural modeling. The suggested framework can serve as an effective complementary tool for molecular dynamics, Normal Mode Analysis, and other prevalent techniques for predicting motion in proteins. We applied our framework to three different model systems. We show that a limited set of experimentally motivated constraints may effectively bias the simulations toward diverse predicates in an outright fashion, from distance constraints to enforcement of loop closure. In particular, our analysis sheds light on mechanisms of protein domain swapping and on the role of different residues in the motion.

  17. Random Decrement

    DEFF Research Database (Denmark)

    Asmussen, J.C.; Ibrahim, S.R.; Brincker, Rune

    Abstraet Thispaper demansirates how to use the Random Decrement (RD) technique for identification o flinear structures subjected to ambient excitation. The theory behind the technique will be presented and guidelines how to choose the different variables will be given. This is done by introducing...

  18. Random Decrement

    DEFF Research Database (Denmark)

    Asmussen, J. C.; Ibrahim, S. R.; Brincker, Rune

    This paper demonstrates how to use the Random Decrement (RD) technique for identification of linear structures subjected to ambient excitation. The theory behind the technique will be presented and guidelines how to choose the different variables will be given. This is done by introducing a new...

  19. Random Decrement

    DEFF Research Database (Denmark)

    Asmussen, J. C.; Ibrahim, R.; Brincker, Rune

    1998-01-01

    This paper demonstrates how to use the Random Decrement (RD) technique for identification of linear structures subjected to ambient excitation. The theory behind the technique will be presented and guidelines how to choose the different variables will be given. This is done by introducing a new...

  20. Random dynamics

    International Nuclear Information System (INIS)

    Bennett, D.L.; Brene, N.; Nielsen, H.B.

    1986-06-01

    The goal of random dynamics is the derivation of the laws of Nature as we know them (standard model) from inessential assumptions. The inessential assumptions made here are expressed as sets of general models at extremely high energies: gauge glass and spacetime foam. Both sets of models lead tentatively to the standard model. (orig.)

  1. Random dynamics

    International Nuclear Information System (INIS)

    Bennett, D.L.

    1987-01-01

    The goal of random dynamics is the derivation of the laws of Nature as we know them (standard model) from inessential assumptions. The inessential assumptions made here are expressed as sets of general models at extremely high energies: Gauge glass and spacetime foam. Both sets of models lead tentatively to the standard model. (orig.)

  2. Random Dynamics

    Science.gov (United States)

    Bennett, D. L.; Brene, N.; Nielsen, H. B.

    1987-01-01

    The goal of random dynamics is the derivation of the laws of Nature as we know them (standard model) from inessential assumptions. The inessential assumptions made here are expressed as sets of general models at extremely high energies: gauge glass and spacetime foam. Both sets of models lead tentatively to the standard model.

  3. The role of topography and lateral velocity heterogeneities on near-source scattering and ground-motion variability

    KAUST Repository

    Imperatori, W.; Mai, Paul Martin

    2015-01-01

    The scattering of seismic waves travelling in the Earth is not only caused by random velocity heterogeneity but also by surface topography. Both factors are known to strongly affect ground-motion complexity even at relatively short distance from

  4. Quantification of renal and diaphragmatic interfractional motion in pediatric image-guided radiation therapy: A multicenter study

    NARCIS (Netherlands)

    Huijskens, Sophie C.; van Dijk, Irma W. E. M.; de Jong, Rianne; Visser, Jorrit; Fajardo, Raquel Dávila; Ronckers, Cécile M.; Janssens, Geert O. R. J.; Maduro, John H.; Rasch, Coen R. N.; Alderliesten, Tanja; Bel, Arjan

    2015-01-01

    To quantify renal and diaphragmatic interfractional motion in order to estimate systematic and random errors, and to investigate the correlation between interfractional motion and patient-specific factors. We used 527 retrospective abdominal-thoracic cone beam CT scans of 39 childhood cancer

  5. Quantification of renal and diaphragmatic interfractional motion in pediatric image-guided radiation therapy: A multicenter study

    NARCIS (Netherlands)

    Huijskens, S.C.; Dijk, I.W. van; Jong, R. de; Visser, J.; Fajardo, R.D.; Ronckers, C.M.; Janssens, G.O.R.J.; Maduro, J.H.; Rasch, C.R.; Alderliesten, T.; Bel, A.

    2015-01-01

    BACKGROUND AND PURPOSE: To quantify renal and diaphragmatic interfractional motion in order to estimate systematic and random errors, and to investigate the correlation between interfractional motion and patient-specific factors. MATERIAL AND METHODS: We used 527 retrospective abdominal-thoracic

  6. 19 CFR 210.26 - Other motions.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 3 2010-04-01 2010-04-01 false Other motions. 210.26 Section 210.26 Customs Duties UNITED STATES INTERNATIONAL TRADE COMMISSION INVESTIGATIONS OF UNFAIR PRACTICES IN IMPORT TRADE ADJUDICATION AND ENFORCEMENT Motions § 210.26 Other motions. Motions pertaining to discovery shall be filed in...

  7. 6 CFR 13.28 - Motions.

    Science.gov (United States)

    2010-01-01

    ... 6 Domestic Security 1 2010-01-01 2010-01-01 false Motions. 13.28 Section 13.28 Domestic Security DEPARTMENT OF HOMELAND SECURITY, OFFICE OF THE SECRETARY PROGRAM FRAUD CIVIL REMEDIES § 13.28 Motions. (a) Any application to the ALJ for an order or ruling will be by motion. Motions will state the relief...

  8. Motion-compensated processing of image signals

    NARCIS (Netherlands)

    2010-01-01

    In a motion-compensated processing of images, input images are down-scaled (scl) to obtain down-scaled images, the down-scaled images are subjected to motion- compensated processing (ME UPC) to obtain motion-compensated images, the motion- compensated images are up-scaled (sc2) to obtain up-scaled

  9. 12 CFR 747.23 - Motions.

    Science.gov (United States)

    2010-01-01

    ... written motions except as otherwise directed by the administrative law judge. Written memorandum, briefs... Procedure § 747.23 Motions. (a) In writing. (1) Except as otherwise provided herein, an application or request for an order or ruling must be made by written motion. (2) All written motions must state with...

  10. 7 CFR 1.327 - Motions.

    Science.gov (United States)

    2010-01-01

    ... be in writing. The ALJ may require that oral motions be reduced to writing. (c) The ALJ may require written motions to be accompanied by supporting memorandums. (d) Within 15 days after a written motion is...) The ALJ may not grant a written motion prior to expiration of the time for filing responses thereto...

  11. A reduced-dimensionality approach to uncovering dyadic modes of body motion in conversations.

    Science.gov (United States)

    Gaziv, Guy; Noy, Lior; Liron, Yuvalal; Alon, Uri

    2017-01-01

    Face-to-face conversations are central to human communication and a fascinating example of joint action. Beyond verbal content, one of the primary ways in which information is conveyed in conversations is body language. Body motion in natural conversations has been difficult to study precisely due to the large number of coordinates at play. There is need for fresh approaches to analyze and understand the data, in order to ask whether dyads show basic building blocks of coupled motion. Here we present a method for analyzing body motion during joint action using depth-sensing cameras, and use it to analyze a sample of scientific conversations. Our method consists of three steps: defining modes of body motion of individual participants, defining dyadic modes made of combinations of these individual modes, and lastly defining motion motifs as dyadic modes that occur significantly more often than expected given the single-person motion statistics. As a proof-of-concept, we analyze the motion of 12 dyads of scientists measured using two Microsoft Kinect cameras. In our sample, we find that out of many possible modes, only two were motion motifs: synchronized parallel torso motion in which the participants swayed from side to side in sync, and still segments where neither person moved. We find evidence of dyad individuality in the use of motion modes. For a randomly selected subset of 5 dyads, this individuality was maintained for at least 6 months. The present approach to simplify complex motion data and to define motion motifs may be used to understand other joint tasks and interactions. The analysis tools developed here and the motion dataset are publicly available.

  12. Thermal insulation

    International Nuclear Information System (INIS)

    Durston, J.G.; Birch, W.; Facer, R.I.; Stuart, R.A.

    1977-01-01

    Reference is made to liquid metal cooled nuclear reactors. In the arrangement described the reactor vessel is clad with thermal insulation comprising a layer of insulating blocks spaced from the wall and from each other; each block is rigidly secured to the wall, and the interspaces are substantially closed against convectional flow of liquid by resilient closure members. A membrane covering is provided for the layer of blocks, with venting means to allow liquid from the reactor vessel to penetrate between the covering and the layer of blocks. The membrane covering may comprise a stainless steel sheet ribbed in orthogonal pattern to give flexibility for the accommodation of thermal strain. The insulating blocks may be comprised of stainless steel or cellular or porous material and may be hollow shells containing ceramic material or gas fillings. (U.K.)

  13. Thermal conductivity of granular materials

    Energy Technology Data Exchange (ETDEWEB)

    Buyevich, Yu A

    1974-01-01

    Stationary heat transfer in a granular material consisting of a continuous medium containing spherical granules of other substances is considered under the assumption that the spatial distribution of granules is random. The effective thermal conductivity characterizing macroscopic heat transfer in such a material is expressed as a certain function of the conductivities and volume fractions of the medium and dispersed substances. For reasons of mathematical analogy, all the results obtained for the thermal conductivity are valid while computing the effective diffusivity of some admixture in granular materials as well as for evaluation of the effective electric conductivity or the mean dielectric and magnetic permeabilities of granular conductors and dielectrics. (23 refs.)

  14. Solar thermal

    International Nuclear Information System (INIS)

    Jones, J.

    2006-01-01

    While wind power is widely acknowledged as the most developed of the 'new' renewables, the number two technology, in terms of installed capacity functioning worldwide, is solar heating, or solar thermal. The author has investigated recent industry reports on how these markets are developing. The authors of an International Energy Agency (IEA) survey studied 41 countries in depth at the end of 2004, revealing that 141 million m 3 - corresponding to an installed capacity of 98.4 GWth - were installed in the sample countries (these nations represent 3.74 billion people, about 57% of the world's population). The installed capacity within the areas studied represents approximately 85%-90% of the solar thermal market worldwide. The use of solar heating varies greatly between countries - even close neighbours - and between economic regions. Its uptake often has more to do with policy than solar resource. There is also different uptake of technology. In China, Europe and Japan, plants with flat-plate and evacuated tube collectors are used, mainly to heat water and for space heating. Unglazed plastic collectors, used mainly for swimming pool heating, meanwhile, dominate the North American markets. Though the majority of solar heating installations today are installed on domestic rooftops, the larger-scale installations should not be overlooked. One important part of the market is the hotel sector - in particular hotels in locations that serve the seasonal summer holiday market, where solar is extremely effective. Likewise hospitals and residential homes, multi-family apartment blocks and sports centres are all good examples of places where solar thermal can deliver results. There are also a growing number of industrial applications, where solar thermal can meet the hot water needs (and possibly more) of a range of industries, such as food processing and agriculture. The ability of solar to provide a heat source for cooling is expected to become increasingly important as

  15. Solar thermal

    Energy Technology Data Exchange (ETDEWEB)

    Jones, J.

    2006-07-15

    While wind power is widely acknowledged as the most developed of the 'new' renewables, the number two technology, in terms of installed capacity functioning worldwide, is solar heating, or solar thermal. The author has investigated recent industry reports on how these markets are developing. The authors of an International Energy Agency (IEA) survey studied 41 countries in depth at the end of 2004, revealing that 141 million m{sup 3} - corresponding to an installed capacity of 98.4 GWth - were installed in the sample countries (these nations represent 3.74 billion people, about 57% of the world's population). The installed capacity within the areas studied represents approximately 85%-90% of the solar thermal market worldwide. The use of solar heating varies greatly between countries - even close neighbours - and between economic regions. Its uptake often has more to do with policy than solar resource. There is also different uptake of technology. In China, Europe and Japan, plants with flat-plate and evacuated tube collectors are used, mainly to heat water and for space heating. Unglazed plastic collectors, used mainly for swimming pool heating, meanwhile, dominate the North American markets. Though the majority of solar heating installations today are installed on domestic rooftops, the larger-scale installations should not be overlooked. One important part of the market is the hotel sector - in particular hotels in locations that serve the seasonal summer holiday market, where solar is extremely effective. Likewise hospitals and residential homes, multi-family apartment blocks and sports centres are all good examples of places where solar thermal can deliver results. There are also a growing number of industrial applications, where solar thermal can meet the hot water needs (and possibly more) of a range of industries, such as food processing and agriculture. The ability of solar to provide a heat source for cooling is expected to become

  16. Motion Learning Based on Bayesian Program Learning

    Directory of Open Access Journals (Sweden)

    Cheng Meng-Zhen

    2017-01-01

    Full Text Available The concept of virtual human has been highly anticipated since the 1980s. By using computer technology, Human motion simulation could generate authentic visual effect, which could cheat human eyes visually. Bayesian Program Learning train one or few motion data, generate new motion data by decomposing and combining. And the generated motion will be more realistic and natural than the traditional one.In this paper, Motion learning based on Bayesian program learning allows us to quickly generate new motion data, reduce workload, improve work efficiency, reduce the cost of motion capture, and improve the reusability of data.

  17. Vertical Motions of Oceanic Volcanoes

    Science.gov (United States)

    Clague, D. A.; Moore, J. G.

    2006-12-01

    Oceanic volcanoes offer abundant evidence of changes in their elevations through time. Their large-scale motions begin with a period of rapid subsidence lasting hundreds of thousands of years caused by isostatic compensation of the added mass of the volcano on the ocean lithosphere. The response is within thousands of years and lasts as long as the active volcano keeps adding mass on the ocean floor. Downward flexure caused by volcanic loading creates troughs around the growing volcanoes that eventually fill with sediment. Seismic surveys show that the overall depression of the old ocean floor beneath Hawaiian volcanoes such as Mauna Loa is about 10 km. This gross subsidence means that the drowned shorelines only record a small part of the total subsidence the islands experienced. In Hawaii, this history is recorded by long-term tide-gauge data, the depth in drill holes of subaerial lava flows and soil horizons, former shorelines presently located below sea level. Offshore Hawaii, a series of at least 7 drowned reefs and terraces record subsidence of about 1325 m during the last half million years. Older sequences of drowned reefs and terraces define the early rapid phase of subsidence of Maui, Molokai, Lanai, Oahu, Kauai, and Niihau. Volcanic islands, such as Maui, tip down toward the next younger volcano as it begins rapid growth and subsidence. Such tipping results in drowned reefs on Haleakala as deep as 2400 m where they are tipped towards Hawaii. Flat-topped volcanoes on submarine rift zones also record this tipping towards the next younger volcano. This early rapid subsidence phase is followed by a period of slow subsidence lasting for millions of years caused by thermal contraction of the aging ocean lithosphere beneath the volcano. The well-known evolution along the Hawaiian chain from high to low volcanic island, to coral island, and to guyot is due to this process. This history of rapid and then slow subsidence is interrupted by a period of minor uplift

  18. Femtosecond quantum dynamics and laser-cooling in thermal molecular systems

    International Nuclear Information System (INIS)

    Warmuth, C.

    2000-01-01

    This work deals with coherent and incoherent vibrational phenomena in thermal systems, wave packet motion and laser-cooling. In the first part, the principle of COIN (Coherence Observation by Interference Noise) has been applied as a new approach to measuring wave packet motion. In the experiment pairs of phase-randomized femtosecond pulses with relative delay-time τ prepare interference fluctuations in the excited state population, so the variance of the correlated fluorescence intensity directly mimics the dynamics of the propagating wave packet. The scheme is demonstrated by measuring the vibrational coherence of wave packet-motion in the B-state of gaseous iodine. The COIN-interferograms obtained recover propagation, recurrences, spreading, and revivals as the typical signature of wave packets. Due to the disharmony of the B-state-potential, fractional revivals have also been found showing the potential of the COIN-technique in quantum-dynamical research. In the second part the fluorescence lifetime of trans-stilbene, isolated and in the presence of 1 atm of Ar gas, respectively, was measured as a function of the detuning of the excitation frequency from the frequency of the 0-0-transition ω 0 . The lifetime was found to decrease on both sides of ω 0 , but the dependence of the lifetime on detuning in the presence of Ar gas is much weaker than for the isolated molecule. Both observations corroborate previous theoretical predictions of laser-cooling of thermal trans-stilbene upon excitation at the ω 0 frequency. The experimental results are in good agreement with theoretical analysis. (author)

  19. OR TEP-II: a FORTRAN Thermal-Ellipsoid Plot Program for crystal structure illustrations

    International Nuclear Information System (INIS)

    Johnson, C.K.

    1976-03-01

    A computer program is described for drawing crystal structure illustrations using a mechanical plotter. Ball-and-stick type illustrations of a quality suitable for publication are produced with either spheres or thermal-motion probability ellipsoids on the atomic sites. The program can produce stereoscopic pairs of illustrations which aid in the visualization of complex packing arrangements of atoms and thermal motion patterns. Interatomic distances, bond angles, and principal axes of thermal motion are also calculated to aid the structural study. The most recent version of the program, OR TEP-II, has a hidden-line-elimination feature to omit those portions of atoms or bonds behind other atoms or bonds

  20. OR TEP-II: a FORTRAN Thermal-Ellipsoid Plot Program for crystal structure illustrations

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, C.K.

    1976-03-01

    A computer program is described for drawing crystal structure illustrations using a mechanical plotter. Ball-and-stick type illustrations of a quality suitable for publication are produced with either spheres or thermal-motion probability ellipsoids on the atomic sites. The program can produce stereoscopic pairs of illustrations which aid in the visualization of complex packing arrangements of atoms and thermal motion patterns. Interatomic distances, bond angles, and principal axes of thermal motion are also calculated to aid the structural study. The most recent version of the program, OR TEP-II, has a hidden-line-elimination feature to omit those portions of atoms or bonds behind other atoms or bonds.

  1. Robot Motion and Control 2011

    CERN Document Server

    2012-01-01

    Robot Motion Control 2011 presents very recent results in robot motion and control. Forty short papers have been chosen from those presented at the sixth International Workshop on Robot Motion and Control held in Poland in June 2011. The authors of these papers have been carefully selected and represent leading institutions in this field. The following recent developments are discussed: • Design of trajectory planning schemes for holonomic and nonholonomic systems with optimization of energy, torque limitations and other factors. • New control algorithms for industrial robots, nonholonomic systems and legged robots. • Different applications of robotic systems in industry and everyday life, like medicine, education, entertainment and others. • Multiagent systems consisting of mobile and flying robots with their applications The book is suitable for graduate students of automation and robotics, informatics and management, mechatronics, electronics and production engineering systems as well as scientists...

  2. Compensation for incoherent ground motion

    International Nuclear Information System (INIS)

    Shigeru, Takeda; Hiroshi, Matsumoto; Masakazu, Yoshioka; Yasunori, Takeuchi; Kikuo, Kudo; Tsuneya, Tsubokawa; Mitsuaki, Nozaki; Kiyotomo, Kawagoe

    1999-01-01

    The power spectrum density and coherence function for ground motions are studied for the construction of the next generation electron-positron linear collider. It should provide a center of mass energy between 500 GeV-1 TeV with luminosity as high as 10 33 to 10 34 cm -2 sec -1 . Since the linear collider has a relatively slow repetition rate, large number of particles and small sizes of the beam should be generated and preserved in the machine to obtain the required high luminosity. One of the most critical parameters is the extremely small vertical beam size at the interaction point, thus a proper alignment system for the focusing and accelerating elements of the machine is necessary to achieve the luminosity. We describe recent observed incoherent ground motions and an alignment system to compensate the distortion by the ground motions. (authors)

  3. Motion sensor technologies in education

    Directory of Open Access Journals (Sweden)

    T. Bratitsis

    2014-05-01

    Full Text Available This paper attempts to raise a discussion regarding motion sensor technologies, mainly seen as peripherals of contemporary video game consoles, by examining their exploitation within educational context. An overview of the existing literature is presented, while attempting to categorize the educational approaches which involve motion sensor technologies, in two parts. The first one concerns the education of people with special needs. The utilization of motion sensor technologies, incorporated by game consoles, in the education of such people is examined. The second one refers to various educational approaches in regular education, under which not so many research approaches, but many teaching ideas can be found. The aim of the paper is to serve as a reference point for every individual/group, willing to explore the Sensor-Based Games Based Learning (SBGBL research area, by providing a complete and structured literature review.

  4. Restoration of motion blurred images

    Science.gov (United States)

    Gaxiola, Leopoldo N.; Juarez-Salazar, Rigoberto; Diaz-Ramirez, Victor H.

    2017-08-01

    Image restoration is a classic problem in image processing. Image degradations can occur due to several reasons, for instance, imperfections of imaging systems, quantization errors, atmospheric turbulence, relative motion between camera or objects, among others. Motion blur is a typical degradation in dynamic imaging systems. In this work, we present a method to estimate the parameters of linear motion blur degradation from a captured blurred image. The proposed method is based on analyzing the frequency spectrum of a captured image in order to firstly estimate the degradation parameters, and then, to restore the image with a linear filter. The performance of the proposed method is evaluated by processing synthetic and real-life images. The obtained results are characterized in terms of accuracy of image restoration given by an objective criterion.

  5. Visualization system of swirl motion

    International Nuclear Information System (INIS)

    Nakayama, K.; Umeda, K.; Ichikawa, T.; Nagano, T.; Sakata, H.

    2004-01-01

    The instrumentation of a system composed of an experimental device and numerical analysis is presented to visualize flow and identify swirling motion. Experiment is performed with transparent material and PIV (Particle Image Velocimetry) instrumentation, by which velocity vector field is obtained. This vector field is then analyzed numerically by 'swirling flow analysis', which estimates its velocity gradient tensor and the corresponding eigenvalue (swirling function). Since an instantaneous flow field in steady/unsteady states is captured by PIV, the flow field is analyzed, and existence of vortices or swirling motions and their locations are identified in spite of their size. In addition, intensity of swirling is evaluated. The analysis enables swirling motion to emerge, even though it is hidden in uniform flow and velocity filed does not indicate any swirling. This visualization system can be applied to investigate condition to control flow or design flow. (authors)

  6. Alpha motion based on a motion detector, but not on the Müller-Lyer illusion

    Science.gov (United States)

    Suzuki, Masahiro

    2014-07-01

    This study examined the mechanism of alpha motion, the apparent motion of the Müller-Lyer figure's shaft that occurs when the arrowheads and arrow tails are alternately presented. The following facts were found: (a) reduced exposure duration decreased the amount of alpha motion, and this phenomenon was not explainable by the amount of the Müller-Lyer illusion; (b) the motion aftereffect occurred after adaptation to alpha motion; (c) occurrence of alpha motion became difficult when the temporal frequency increased, and this characteristic of alpha motion was similar to the characteristic of a motion detector that motion detection became difficult when the temporal frequency increased from the optimal frequency. These findings indicated that alpha motion occurs on the basis of a motion detector but not on the Müller-Lyer illusion, and that the mechanism of alpha motion is the same as that of general motion perception.

  7. Motion artifacts in computed tomography

    International Nuclear Information System (INIS)

    Yang, C.K.

    1979-01-01

    In the year 1972, the first Computed Tomography Scanner (or CT) was introduced and caused a revolution in the field of Diagnostic Radiology. A tomogram is a cross-sectional image of a three-dimensional object obtained through non-invasive measurements. The image that is presented is very similar to what would be seen if a thin cross-sectional slice of the patient was examined. In Computed Tomography, x-rays are passed through the body of a patient in many different directions and their attenuation is detected. By using some mathematical theorems, the attenuation information can be converted into the density of the patient along the x-ray path. Combined with modern sophisticated computer signal processing technology, a cross-sectional image can be generated and displayed on a TV monitor. Usually a good CT image relies on the patient not moving during the x-ray scanning. However, for some unconscious or severely ill patients, this is very difficult to achieve. Thus, the motion during the scan causes the so-called motion artifacts which distort the displayed image and sometimes these motion artifacts make diagnosis impossible. Today, to remove or avoid motion artifacts is one of the major efforts in developing new scanner systems. In this thesis, a better understanding of the motion artifacts problem in CT scaning is gained through computer simulations, real scanner experiments and theoretical analyses. The methods by which the distorted image can be improved are simulated also. In particular, it is assumed that perfect knowledge of the patient motion is known since this represents the theoretical limit on how well the distorted image can be improved

  8. Mental imagery of gravitational motion.

    Science.gov (United States)

    Gravano, Silvio; Zago, Myrka; Lacquaniti, Francesco

    2017-10-01

    There is considerable evidence that gravitational acceleration is taken into account in the interaction with falling targets through an internal model of Earth gravity. Here we asked whether this internal model is accessed also when target motion is imagined rather than real. In the main experiments, naïve participants grasped an imaginary ball, threw it against the ceiling, and caught it on rebound. In different blocks of trials, they had to imagine that the ball moved under terrestrial gravity (1g condition) or under microgravity (0g) as during a space flight. We measured the speed and timing of the throwing and catching actions, and plotted ball flight duration versus throwing speed. Best-fitting duration-speed curves estimate the laws of ball motion implicit in the participant's performance. Surprisingly, we found duration-speed curves compatible with 0g for both the imaginary 0g condition and the imaginary 1g condition, despite the familiarity with Earth gravity effects and the added realism of performing the throwing and catching actions. In a control experiment, naïve participants were asked to throw the imaginary ball vertically upwards at different heights, without hitting the ceiling, and to catch it on its way down. All participants overestimated ball flight durations relative to the durations predicted by the effects of Earth gravity. Overall, the results indicate that mental imagery of motion does not have access to the internal model of Earth gravity, but resorts to a simulation of visual motion. Because visual processing of accelerating/decelerating motion is poor, visual imagery of motion at constant speed or slowly varying speed appears to be the preferred mode to perform the tasks. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Roll motion stimuli : sensory conflict, perceptual weighting and motion sickness

    NARCIS (Netherlands)

    Graaf, B. de; Bles, W.; Bos, J.E.

    1998-01-01

    In an experiment with seventeen subjects interactions of visual roll motion stimuli and vestibular body tilt stimuli were examined in determining the subjective vertical. Interindi-vidual differences in weighting the visual information were observed, but in general visual and vestibular responses

  10. Motion Model Employment using interacting Motion Model Algorithm

    DEFF Research Database (Denmark)

    Hussain, Dil Muhammad Akbar

    2006-01-01

    The paper presents a simulation study to track a maneuvering target using a selective approach in choosing Interacting Multiple Models (IMM) algorithm to provide a wider coverage to track such targets.  Initially, there are two motion models in the system to track a target.  Probability of each m...

  11. Wave motion in elastic solids

    CERN Document Server

    Graff, Karl F

    1991-01-01

    This highly useful textbook presents comprehensive intermediate-level coverage of nearly all major topics of elastic wave propagation in solids. The subjects range from the elementary theory of waves and vibrations in strings to the three-dimensional theory of waves in thick plates. The book is designed not only for a wide audience of engineering students, but also as a general reference for workers in vibrations and acoustics. Chapters 1-4 cover wave motion in the simple structural shapes, namely strings, longitudinal rod motion, beams and membranes, plates and (cylindrical) shells. Chapter

  12. Motion of rectangular prismatic bodies

    International Nuclear Information System (INIS)

    Poreh, M.; Wray, R.N.

    1979-01-01

    Rectangular prismatic bodies can assume either a translatory or an auto-rotating mode of motion during free motion in the atmosphere. The translatory mode is stable only when the dimensionless moment of inertia of the bodies is large, however, large perturbations will always start auto-rotation. The characteristics of the auto-rotational mode are shown to depend primarily on the aspect ratio of the bodies which determines the dimensionless rotational speed and the lift coefficient. Both the average drag and lift-coefficients of auto-rotating bodies are estimated, but it is shown that secondary effects make it impossible to determine their exact trajectories in atmospheric flows

  13. Estimation of strong ground motion

    International Nuclear Information System (INIS)

    Watabe, Makoto

    1993-01-01

    Fault model has been developed to estimate a strong ground motion in consideration of characteristics of seismic source and propagation path of seismic waves. There are two different approaches in the model. The first one is a theoretical approach, while the second approach is a semi-empirical approach. Though the latter is more practical than the former to be applied to the estimation of input motions, it needs at least the small-event records, the value of the seismic moment of the small event and the fault model of the large event

  14. Biological Motion Perception in Autism

    Directory of Open Access Journals (Sweden)

    J Cusack

    2011-04-01

    Full Text Available Typically developing adults can readily recognize human actions, even when conveyed to them via point-like markers placed on the body of the actor (Johansson, 1973. Previous research has suggested that children affected by autism spectrum disorder (ASD are not equally sensitive to this type of visual information (Blake et al, 2003, but it remains unknown why ASD would impact the ability to perceive biological motion. We present evidence which looks at how adolescents and adults with autism are affected by specific factors which are important in biological motion perception, such as (eg, inter-agent synchronicity, upright/inverted, etc.

  15. Empirical recurrence rates for ground motion signals on planetary surfaces

    Science.gov (United States)

    Lorenz, Ralph D.; Panning, Mark

    2018-03-01

    We determine the recurrence rates of ground motion events as a function of sensed velocity amplitude at several terrestrial locations, and make a first interplanetary comparison with measurements on the Moon, Mars, Venus and Titan. This empirical approach gives an intuitive order-of-magnitude guide to the observed ground motion (including both tectonic and ocean- and atmosphere-forced signals) of these locations as a guide to instrument expectations on future missions, without invoking interior models and specific sources: for example a Venera-14 observation of possible ground motion indicates a microseismic environment mid-way between noisy and quiet terrestrial locations. Quiet terrestrial regions see a peak velocity amplitude in mm/s roughly equal to 0.3*N(-0.7), where N is the number of "events" (half-hour intervals in which a given peak ground motion is exceeded) observed per year. The Apollo data show endogenous seismic signals for a given recurrence rate that are typically about 10,000 times smaller in amplitude than a quiet site on Earth, although local thermally-induced moonquakes are much more common. Viking data masked for low-wind periods appear comparable with a quiet terrestrial site, whereas a Venera observation of microseisms suggests ground motion more similar to a more active terrestrial location. Recurrence rate plots from in-situ measurements provide a context for seismic instrumentation on future planetary missions, e.g. to guide formulation of data compression schemes. While even small geophones can discriminate terrestrial activity rates, observations with guidance accelerometers are typically too insensitive to provide meaningful constraints (i.e. a non-zero number of "events") on actual ground motion observations unless operated for very long periods.

  16. Example-based human motion denoising.

    Science.gov (United States)

    Lou, Hui; Chai, Jinxiang

    2010-01-01

    With the proliferation of motion capture data, interest in removing noise and outliers from motion capture data has increased. In this paper, we introduce an efficient human motion denoising technique for the simultaneous removal of noise and outliers from input human motion data. The key idea of our approach is to learn a series of filter bases from precaptured motion data and use them along with robust statistics techniques to filter noisy motion data. Mathematically, we formulate the motion denoising process in a nonlinear optimization framework. The objective function measures the distance between the noisy input and the filtered motion in addition to how well the filtered motion preserves spatial-temporal patterns embedded in captured human motion data. Optimizing the objective function produces an optimal filtered motion that keeps spatial-temporal patterns in captured motion data. We also extend the algorithm to fill in the missing values in input motion data. We demonstrate the effectiveness of our system by experimenting with both real and simulated motion data. We also show the superior performance of our algorithm by comparing it with three baseline algorithms and to those in state-of-art motion capture data processing software such as Vicon Blade.

  17. Simulation of respiratory motion during IMRT dose delivery

    International Nuclear Information System (INIS)

    Mohn, Silje; Wasboe, Ellen

    2011-01-01

    Background. When intensity modulated radiation therapy (IMRT) is realised with dynamic multi-leaf collimators (MLC) and given under respiratory motion, dosimetric errors may occur. These errors are a consequence of the dose blurring and the interplay between the organ motion and the leaf motion. In the present study, a model for evaluating these dosimetric effects for patient-specific cases has been developed and tested. Material and methods. In the purpose written software, three dimensional (3D) dose distributions can be calculated both with and without a generated breathing cycle. To validate the presented model and illustrate its application, periodic breathing cycles were generated, where the starting phase was set randomly for each field during the calculations. Respiration in the anterior-posterior (AP), superior-inferior (SI) and left-right (LR) direction was tested and verified. To illustrate the application of the presented model, two 5-fields IMRT plans with different complexity were calculated with a 2 cm peak-to-peak motion in the AP direction for one fraction and for 25 fractions. Results. The results showed that the calculation method is of good accuracy, in particular for IMRT plans consisting of several fields, where 97% of the pixels within the body fulfilled a tolerance set to 4% dose difference and 4 mm distance to agreement (DTA). For the two IMRT plans with different complexity, pronounced respiratory induced dose errors, which increased with increasing complexity, were found for both one fraction and 25 fractions, but due to the random stating phase the interplay effect was considerably reduced for the plans consisting of 25 fractions. This illustrates how the dosimetric effects will vary depending on the dose plan and on the number of fractions investigated. Conclusion. For patient specific cases, the model can with good accuracy calculate 3D dose distributions both with and without respiratory motion, and evaluate the dosimetric effects

  18. Effects on ground motion related to spatial variability

    International Nuclear Information System (INIS)

    Vanmarcke, E.H.

    1987-01-01

    Models of the spectral content and the space-time correlation structure of strong earthquake ground motion are combined with transient random vibration analysis to yield site-specific response spectra that can account for the effect of local spatial averaging of the ground motion across a rigid foundation of prescribed size. The methodology is presented with reference to sites in eastern North America, although the basic approach is applicable to other seismic regions provided the source and attenuation parameters are regionally adjusted. Parameters in the spatial correlation model are based on data from the SMART-I accelerograph array, and the sensitivity of response spectra reduction factors with respect to these parameters is examined. The starting point of the analysis is the Fourier amplitude spectrum of site displacement expresses as a function of earthquake source parameters and source-to-site distance. The bedrock acceleration spectral density function at a point, derived from the displacement spectrum, is modified to account for anelastic attenuation, and where appropriate, for local soil effects and/or local spatial averaging across a foundation. Transient random vibration analysis yields approximate analytical expressions for median ground motion amplitudes and median response spectra of an earthquake defined in terms of its spectral density function and strong motion duration. The methodology is illustrated for three events characterized by their m b magnitude and epicentral distance. The focus in this paper is on the stochastic response prediction methodology enabling explicit accounting for strong motion duration and the effect of local spatial averaging on response spectra. The numerical examples enable a preliminary assessment of the reduction of response spectral amplitudes attributable to local spatial averaging across rigid foundations of different sizes. 36 refs

  19. Magnetic field line random walk in non-axisymmetric turbulence

    International Nuclear Information System (INIS)

    Tautz, R.C.; Lerche, I.

    2011-01-01

    Including a random component of a magnetic field parallel to an ambient field introduces a mean perpendicular motion to the average field line. This effect is normally not discussed because one customarily chooses at the outset to ignore such a field component in discussing random walk and diffusion of field lines. A discussion of the basic effect is given, indicating that any random magnetic field with a non-zero helicity will lead to such a non-zero perpendicular mean motion. Several exact analytic illustrations are given of the effect as well as a simple numerical illustration. -- Highlights: → For magnetic field line random walk all magnetic field components are important. → Non-vanishing magnetic helicity leads to mean perpendicular motion. → Analytically exact stream functions illustrate that the novel transverse effect exists.

  20. Functionals of Brownian motion, localization and metric graphs

    International Nuclear Information System (INIS)

    Comtet, Alain; Desbois, Jean; Texier, Christophe

    2005-01-01

    We review several results related to the problem of a quantum particle in a random environment. In an introductory part, we recall how several functionals of Brownian motion arise in the study of electronic transport in weakly disordered metals (weak localization). Two aspects of the physics of the one-dimensional strong localization are reviewed: some properties of the scattering by a random potential (time delay distribution) and a study of the spectrum of a random potential on a bounded domain (the extreme value statistics of the eigenvalues). Then we mention several results concerning the diffusion on graphs, and more generally the spectral properties of the Schroedinger operator on graphs. The interest of spectral determinants as generating functions characterizing the diffusion on graphs is illustrated. Finally, we consider a two-dimensional model of a charged particle coupled to the random magnetic field due to magnetic vortices. We recall the connection between spectral properties of this model and winding functionals of planar Brownian motion. (topical review)

  1. Root cause analysis of thermal sleeve separation

    Energy Technology Data Exchange (ETDEWEB)

    Jo, J. C.; Jhung, M. J.; Yu, S. O.; Kim, H. J.; Yune, Y. K.; Park, J. Y

    2006-01-15

    Thermal sleeves in the shape of thin wall cylinder seated inside the nozzle part of each Safety Injection (SI) line at Pressurized Water Reactors (PWRs) have such functions as prevention and relief of potential excessive transient thermal stress in the wall of SI line nozzle part which is initially heated up with hot water flowing in the primary coolant piping system when cold water is injected into the system through the SI nozzles during the SI operation mode. Recently, mechanical failures that the sleeves were separated from the SI branch pipe and fell into the connected cold leg main pipe occurred in sequence at some typical PWR plants in Korea. To find out the root cause of thermal sleeve breakaway failures, the flow situation in the junction of primary coolant main pipe and SI branch pipe, and the vibration modal characteristics of the thermal sleeve are investigated in detail by using both Computational Fluid Dynamic (CFD) code and structure analysis finite element code. As the results, the transient response in fluid force exerting on the local part of thermal sleeve wall surface to the primary coolant flow through the pipe junction area during the normal reactor operation mode shows oscillatory characteristics with frequencies ranging from 17 to 18, which coincide with one of the lower mode natural frequencies of thermal sleeve having a pinned support condition on the circumferential prominence on the outer surface of thermal sleeve which is put into the circumferential groove on the inner surface of SI nozzle at the mid-height of the thermal sleeve. In addition, the variation of force on the thermal sleeve surface yields alternating torques in the directions of two rectangular axes which are perpendicular to the longitudinal axis of cylindrical thermal sleeve, which cause rolling, pitching and rotating motions of the thermal sleeve. Consequently, it is seen that this flow situation surrounding the thermal sleeve during the normal reactor operation can

  2. Dynamic chaos phenomenon and coherent radiation accompanying high energy particle motion through crystals

    International Nuclear Information System (INIS)

    Akhiezer, A.I.; Truten', V.I.; Shul'ga, N.F.

    1991-01-01

    A crystal has a regular structure, therefore every motion in such a structure seems to be regular. However, it is not actually so and even in perfect crystals the particle motion may be either regular or chaotic. Everything depends on the number of integrals of motion determining a particle trajectory. The character of particle motion in a crystal, i.e. its regularity or chaoticity, affects many physical processes accompanying the particle's motion. In this paper we shall consider the effect of dynamic chaos on the coherent radiation of fast particles in a crystal. We also consider the validity conditions of coherent radiation theory results, the role of the second and higher Born approximations in the radiation theory of fast particles in crystals, the continuous string approximation in this theory, the coherent radiation in the model of random strings, and the multiple scattering effect on the coherent radiation. (author)

  3. A triboelectric motion sensor in wearable body sensor network for human activity recognition.

    Science.gov (United States)

    Hui Huang; Xian Li; Ye Sun

    2016-08-01

    The goal of this study is to design a novel triboelectric motion sensor in wearable body sensor network for human activity recognition. Physical activity recognition is widely used in well-being management, medical diagnosis and rehabilitation. Other than traditional accelerometers, we design a novel wearable sensor system based on triboelectrification. The triboelectric motion sensor can be easily attached to human body and collect motion signals caused by physical activities. The experiments are conducted to collect five common activity data: sitting and standing, walking, climbing upstairs, downstairs, and running. The k-Nearest Neighbor (kNN) clustering algorithm is adopted to recognize these activities and validate the feasibility of this new approach. The results show that our system can perform physical activity recognition with a successful rate over 80% for walking, sitting and standing. The triboelectric structure can also be used as an energy harvester for motion harvesting due to its high output voltage in random low-frequency motion.

  4. Nuclear moments of inertia and wobbling motions in triaxial superdeformed nuclei

    International Nuclear Information System (INIS)

    Matsuzaki, Masayuki; Shimizu, Yoshifumi R.; Matsuyanagi, Kenichi

    2004-01-01

    The wobbling motion excited on triaxial superdeformed nuclei is studied in terms of the cranked shell model plus random phase approximation. First, by calculating at a low rotational frequency the γ dependence of the three moments of inertia associated with the wobbling motion, the mechanism of the appearance of the wobbling motion in positive-γ nuclei is clarified theoretically--the rotational alignment of the πi 13/2 quasiparticle(s) is the essential condition. This indicates that the wobbling motion is a collective motion that is sensitive to the single-particle alignment. Second, we prove that the observed unexpected rotational-frequency dependence of the wobbling frequency is an outcome of the rotational-frequency dependent dynamical moments of inertia

  5. Integration time for the perception of depth from motion parallax.

    Science.gov (United States)

    Nawrot, Mark; Stroyan, Keith

    2012-04-15

    The perception of depth from relative motion is believed to be a slow process that "builds-up" over a period of observation. However, in the case of motion parallax, the potential accuracy of the depth estimate suffers as the observer translates during the viewing period. Our recent quantitative model for the perception of depth from motion parallax proposes that relative object depth (d) can be determined from retinal image motion (dθ/dt), pursuit eye movement (dα/dt), and fixation distance (f) by the formula: d/f≈dθ/dα. Given the model's dynamics, it is important to know the integration time required by the visual system to recover dα and dθ, and then estimate d. Knowing the minimum integration time reveals the incumbent error in this process. A depth-phase discrimination task was used to determine the time necessary to perceive depth-sign from motion parallax. Observers remained stationary and viewed a briefly translating random-dot motion parallax stimulus. Stimulus duration varied between trials. Fixation on the translating stimulus was monitored and enforced with an eye-tracker. The study found that relative depth discrimination can be performed with presentations as brief as 16.6 ms, with only two stimulus frames providing both retinal image motion and the stimulus window motion for pursuit (mean range=16.6-33.2 ms). This was found for conditions in which, prior to stimulus presentation, the eye was engaged in ongoing pursuit or the eye was stationary. A large high-contrast masking stimulus disrupted depth-discrimination for stimulus presentations less than 70-75 ms in both pursuit and stationary conditions. This interval might be linked to ocular-following response eye-movement latencies. We conclude that neural mechanisms serving depth from motion parallax generate a depth estimate much more quickly than previously believed. We propose that additional sluggishness might be due to the visual system's attempt to determine the maximum dθ/dα ratio

  6. Storyboard dalam Pembuatan Motion Graphic

    Directory of Open Access Journals (Sweden)

    Satrya Mahardhika

    2013-10-01

    Full Text Available Motion graphics is one category in the animation that makes animation with lots of design elements in each component. Motion graphics needs long process including preproduction, production, and postproduction. Preproduction has an important role so that the next stage may provide guidance or instructions for the production process or the animation process. Preproduction includes research, making the story, script, screenplay, character, environment design and storyboards. The storyboard will be determined through camera angles, blocking, sets, and many supporting roles involved in a scene. Storyboard is also useful as a production reference in recording or taping each scene in sequence or as an efficient priority. The example used is an ad creation using motion graphic animation storyboard which has an important role as a blueprint for every scene and giving instructions to make the transition movement, layout, blocking, and defining camera movement that everything should be done periodically in animation production. Planning before making the animation or motion graphic will make the job more organized, presentable, and more efficient in the process.  

  7. Rotational damping motion in nuclei

    International Nuclear Information System (INIS)

    Egido, J.L.; Faessler, A.

    1991-01-01

    The recently proposed model to explain the mechanism of the rotational motion damping in nuclei is exactly solved. When compared with the earlier approximative solution, we find significative differences in the low excitation energy limit (i.e. Γ μ 0 ). For the strength functions we find distributions going from the Wigner semicircle through gaussians to Breit-Wigner shapes. (orig.)

  8. Procedure to describe clavicular motion.

    Science.gov (United States)

    Gutierrez Delgado, Guivey; De Beule, Matthieu; Ortega Cardentey, Dolgis R; Segers, Patrick; Iznaga Benítez, Arsenio M; Rodríguez Moliner, Tania; Verhegghe, Benedict; Palmans, Tanneke; Van Hoof, Tom; Van Tongel, Alexander

    2017-03-01

    For many years, researchers have attempted to describe shoulder motions by using different mathematical methods. The aim of this study was to describe a procedure to quantify clavicular motion. The procedure proposed for the kinematic analysis consists of 4 main processes: 3 transcortical pins in the clavicle, motion capture, obtaining 3-dimensional bone models, and data processing. Clavicular motion by abduction (30° to 150°) and flexion (55° to 165°) were characterized by an increment of retraction of 27° to 33°, elevation of 25° to 28°, and posterior rotation of 14° to 15°, respectively. In circumduction, clavicular movement described an ellipse, which was reflected by retraction and elevation. Kinematic analysis shows that the articular surfaces move by simultaneously rolling and sliding on the convex surface of the sternum for the 3 movements of abduction, flexion, and circumduction. The use of 3 body landmarks in the clavicle and the direct measurement of bone allowed description of the osteokinematic and arthrokinematic movement of the clavicle. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  9. Pendulum Motion and Differential Equations

    Science.gov (United States)

    Reid, Thomas F.; King, Stephen C.

    2009-01-01

    A common example of real-world motion that can be modeled by a differential equation, and one easily understood by the student, is the simple pendulum. Simplifying assumptions are necessary for closed-form solutions to exist, and frequently there is little discussion of the impact if those assumptions are not met. This article presents a…

  10. Motion planning for multiple robots

    NARCIS (Netherlands)

    Aronov, B.; Berg, de M.; van der Stappen, A.F.; Svestka, P.; Vleugels, J.M.

    1999-01-01

    We study the motion-planning problem for pairs and triples of robots operating in a shared workspace containing n obstacles. A standard way to solve such problems is to view the collection of robots as one composite robot, whose number of degrees of freedom is d , the sum of the numbers of degrees

  11. Quantum equations from Brownian motions

    International Nuclear Information System (INIS)

    Rajput, B.S.

    2011-01-01

    Classical Schrodinger and Dirac equations have been derived from Brownian motions of a particle, it has been shown that the classical Schrodinger equation can be transformed to usual Schrodinger Quantum equation on applying Heisenberg uncertainty principle between position and momentum while Dirac Quantum equation follows it's classical counter part on applying Heisenberg uncertainly principle between energy and time without applying any analytical continuation. (author)

  12. Molecular motion in restricted geometries

    Indian Academy of Sciences (India)

    Molecular dynamics in restricted geometries is known to exhibit anomalous behaviour. Diffusion, translational or rotational, of molecules is altered significantly on confinement in restricted geometries. Quasielastic neutron scattering (QENS) offers a unique possibility of studying molecular motion in such systems. Both time ...

  13. Anharmonicity in nuclear wobbling motion

    International Nuclear Information System (INIS)

    Oi, M.

    2007-01-01

    An unexpected strong anharmonicity was observed in the wobbling spectrum in 163 Lu. In an attempt to understand what causes the deviation from the original wobbling model by Bohr and Mottelson, an analysis is presented using several different approaches, such as exact diagonalization, a semiclassical model to deal with anharmonic wobbling motion, and a microscopic method based on the self-consistent cranking calculation

  14. Genetics Home Reference: motion sickness

    Science.gov (United States)

    ... motion, particularly traveling in a car, bus, train, airplane, or boat. Amusement park rides, skiing, and virtual ... Association ClinicalTrials.gov (1 link) ClinicalTrials.gov Scientific Articles on PubMed (1 link) PubMed OMIM (1 link) ...

  15. Faraday's Law and Seawater Motion

    Science.gov (United States)

    De Luca, R.

    2010-01-01

    Using Faraday's law, one can illustrate how an electromotive force generator, directly utilizing seawater motion, works. The conceptual device proposed is rather simple in its components and can be built in any high school or college laboratory. The description of the way in which the device generates an electromotive force can be instructive not…

  16. Annotated Bibliography on Relative Motion

    Science.gov (United States)

    1992-03-01

    displace the sheave, and motive means operating the power ram. Preferably, the power run is subjected to i constant upward pneumatic force to provide...NCIEI- Report N- 1187 (Oct 1971). The theory is de\\ eloped for the swinging rmotion induced in a wire suspended load due to the hori7zontal motion of a

  17. Edge dependent motion blur reduction

    NARCIS (Netherlands)

    2010-01-01

    The invention relates to a method and a circuit arrangement to reduce motion blur of images shown in non-stroboscopic display devices, in particular Liquid Crystal Display Panels (LCDs). Thin Film Transistor Displays (TFTs), Color Sequential Displays. Plasma Display Panels (PDPs), Digital Micro

  18. Smoothing of respiratory motion traces for motion-compensated radiotherapy.

    Science.gov (United States)

    Ernst, Floris; Schlaefer, Alexander; Schweikard, Achim

    2010-01-01

    The CyberKnife system has been used successfully for several years to radiosurgically treat tumors without the need for stereotactic fixation or sedation of the patient. It has been shown that tumor motion in the lung, liver, and pancreas can be tracked with acceptable accuracy and repeatability. However, highly precise targeting for tumors in the lower abdomen, especially for tumors which exhibit strong motion, remains problematic. Reasons for this are manifold, like the slow tracking system operating at 26.5 Hz, and using the signal from the tracking camera "as is." Since the motion recorded with the camera is used to compensate for system latency by prediction and the predicted signal is subsequently used to infer the tumor position from a correlation model based on x-ray imaging of gold fiducials around the tumor, camera noise directly influences the targeting accuracy. The goal of this work is to establish the suitability of a new smoothing method for respiratory motion traces used in motion-compensated radiotherapy. The authors endeavor to show that better prediction--With a lower rms error of the predicted signal--and/or smoother prediction is possible using this method. The authors evaluated six commercially available tracking systems (NDI Aurora, PolarisClassic, Polaris Vicra, MicronTracker2 H40, FP5000, and accuTrack compact). The authors first tracked markers both stationary and while in motion to establish the systems' noise characteristics. Then the authors applied a smoothing method based on the a trous wavelet decomposition to reduce the devices' noise level. Additionally, the smoothed signal of the moving target and a motion trace from actual human respiratory motion were subjected to prediction using the MULIN and the nLMS2 algorithms. The authors established that the noise distribution for a static target is Gaussian and that when the probe is moved such as to mimic human respiration, it remains Gaussian with the exception of the FP5000 and the

  19. Smoothing of respiratory motion traces for motion-compensated radiotherapy

    International Nuclear Information System (INIS)

    Ernst, Floris; Schlaefer, Alexander; Schweikard, Achim

    2010-01-01

    Purpose: The CyberKnife system has been used successfully for several years to radiosurgically treat tumors without the need for stereotactic fixation or sedation of the patient. It has been shown that tumor motion in the lung, liver, and pancreas can be tracked with acceptable accuracy and repeatability. However, highly precise targeting for tumors in the lower abdomen, especially for tumors which exhibit strong motion, remains problematic. Reasons for this are manifold, like the slow tracking system operating at 26.5 Hz, and using the signal from the tracking camera ''as is''. Since the motion recorded with the camera is used to compensate for system latency by prediction and the predicted signal is subsequently used to infer the tumor position from a correlation model based on x-ray imaging of gold fiducials around the tumor, camera noise directly influences the targeting accuracy. The goal of this work is to establish the suitability of a new smoothing method for respiratory motion traces used in motion-compensated radiotherapy. The authors endeavor to show that better prediction--With a lower rms error of the predicted signal--and/or smoother prediction is possible using this method. Methods: The authors evaluated six commercially available tracking systems (NDI Aurora, PolarisClassic, Polaris Vicra, MicronTracker2 H40, FP5000, and accuTrack compact). The authors first tracked markers both stationary and while in motion to establish the systems' noise characteristics. Then the authors applied a smoothing method based on the a trous wavelet decomposition to reduce the devices' noise level. Additionally, the smoothed signal of the moving target and a motion trace from actual human respiratory motion were subjected to prediction using the MULIN and the nLMS 2 algorithms. Results: The authors established that the noise distribution for a static target is Gaussian and that when the probe is moved such as to mimic human respiration, it remains Gaussian with the

  20. Dynamical correlations for circular ensembles of random matrices

    International Nuclear Information System (INIS)

    Nagao, Taro; Forrester, Peter

    2003-01-01

    Circular Brownian motion models of random matrices were introduced by Dyson and describe the parametric eigenparameter correlations of unitary random matrices. For symmetric unitary, self-dual quaternion unitary and an analogue of antisymmetric Hermitian matrix initial conditions, Brownian dynamics toward the unitary symmetry is analyzed. The dynamical correlation functions of arbitrary number of Brownian particles at arbitrary number of times are shown to be written in the forms of quaternion determinants, similarly as in the case of Hermitian random matrix models