Hubbard, W B
2016-01-01
In anticipation of new observational results for Jupiter's axial moment of inertia and gravitational zonal harmonic coefficients from the forthcoming Juno orbiter, we present a number of preliminary Jupiter interior models. We combine results from ab initio computer simulations of hydrogen-helium mixtures, including immiscibility calculations, with a new nonperturbative calculation of Jupiter's zonal harmonic coefficients, to derive a self-consistent model for the planet's external gravity and moment of inertia. We assume helium rain modified the interior temperature and composition profiles. Our calculation predicts zonal harmonic values to which measurements can be compared. Although some models fit the observed (pre-Juno) second- and fourth-order zonal harmonics to within their error bars, our preferred reference model predicts a fourth-order zonal harmonic whose absolute value lies above the pre-Juno error bars. This model has a dense core of about 12 Earth masses, and a hydrogen-helium-rich envelope with...
Hubbard, W. B.; Militzer, B.
2016-03-01
In anticipation of new observational results for Jupiter's axial moment of inertia and gravitational zonal harmonic coefficients from the forthcoming Juno orbiter, we present a number of preliminary Jupiter interior models. We combine results from ab initio computer simulations of hydrogen-helium mixtures, including immiscibility calculations, with a new nonperturbative calculation of Jupiter's zonal harmonic coefficients, to derive a self-consistent model for the planet's external gravity and moment of inertia. We assume helium rain modified the interior temperature and composition profiles. Our calculation predicts zonal harmonic values to which measurements can be compared. Although some models fit the observed (pre-Juno) second- and fourth-order zonal harmonics to within their error bars, our preferred reference model predicts a fourth-order zonal harmonic whose absolute value lies above the pre-Juno error bars. This model has a dense core of about 12 Earth masses and a hydrogen-helium-rich envelope with approximately three times solar metallicity.
Energy Technology Data Exchange (ETDEWEB)
Hubbard, W. B. [Lunar and Planetary Laboratory, The University of Arizona, Tucson, AZ 85721 (United States); Militzer, B. [Department of Earth and Planetary Science, Department of Astronomy, University of California, Berkeley, CA 94720 (United States)
2016-03-20
In anticipation of new observational results for Jupiter's axial moment of inertia and gravitational zonal harmonic coefficients from the forthcoming Juno orbiter, we present a number of preliminary Jupiter interior models. We combine results from ab initio computer simulations of hydrogen–helium mixtures, including immiscibility calculations, with a new nonperturbative calculation of Jupiter's zonal harmonic coefficients, to derive a self-consistent model for the planet's external gravity and moment of inertia. We assume helium rain modified the interior temperature and composition profiles. Our calculation predicts zonal harmonic values to which measurements can be compared. Although some models fit the observed (pre-Juno) second- and fourth-order zonal harmonics to within their error bars, our preferred reference model predicts a fourth-order zonal harmonic whose absolute value lies above the pre-Juno error bars. This model has a dense core of about 12 Earth masses and a hydrogen–helium-rich envelope with approximately three times solar metallicity.
Extended Heat Deposition in Hot Jupiters: Application to Ohmic Heating
Ginzburg, Sivan
2015-01-01
Many giant exoplanets in close orbits have observed radii which exceed theoretical predictions. One suggested explanation for this discrepancy is heat deposited deep inside the atmospheres of these "hot Jupiters". Here, we study extended power sources which distribute heat from the photosphere to the deep interior of the planet. Our analytical treatment is a generalization of a previous analysis of localized "point sources". We model the deposition profile as a power law in the optical depth and find that planetary cooling and contraction halt when the internal luminosity (i.e. cooling rate) of the planet drops below the heat deposited in the planet's convective region. A slowdown in the evolutionary cooling prior to equilibrium is possible only for sources which do not extend to the planet's center. We estimate the Ohmic dissipation resulting from the interaction between the atmospheric winds and the planet's magnetic field, and apply our analytical model to Ohmically heated planets. Our model can account fo...
Tidal Response of Preliminary Jupiter Model
Wahl, Sean M; Hubbard, Willam B.; Militzer, Burkhard
2016-01-01
In anticipation of improved observational data for Jupiter's gravitational field from the Juno spacecraft, we predict the static tidal response for a variety of Jupiter interior models based on ab initio computer simulations of hydrogen-helium mixtures. We calculate hydrostatic-equilibrium gravity terms using the non-perturbative concentric Maclaurin Spheroid (CMS) method that eliminates lengthy expansions used in the theory of figures. Our method captures terms arising from the coupled tidal...
Tidal Response of Preliminary Jupiter Model
Wahl, Sean M; Militzer, Burkhard
2016-01-01
In anticipation of improved observational data for Jupiter's gravitational field from the Juno spacecraft, we predict the static tidal response for a variety of Jupiter interior models based on ab initio computer simulations of hydrogen-helium mixtures. We calculate hydrostatic-equilibrium gravity terms using the non-perturbative concentric Maclaurin Spheroid (CMS) method that eliminates lengthy expansions used in the theory of figures. Our method captures terms arising from the coupled tidal and rotational perturbations, which we find to be important for a rapidly-rotating planet like Jupiter. Our predicted static tidal Love number $k_2 = 0.5900$ is $\\sim$10\\% larger than previous estimates. The value is, as expected, highly correlated with the zonal harmonic coefficient $J_2$, and is thus nearly constant when plausible changes are made to interior structure while holding $J_2$ fixed at the observed value. We note that the predicted static $k_2$ might change due to Jupiter's dynamical response to the Galilea...
Penne, Barbra
2017-01-01
Our solar system's largest planet is huge enough that all of the system's other planets could fit inside it. Although Jupiter has been known since ancient times, scientists are still learning exciting new information about the planet and its satellites today. In fact, several of its moons are now believed to have oceans below their icy surfaces. Chapters focus on topics such as Jupiter's orbit and rotation, rings, atmosphere, and moons, as well as on the space missions that have helped us get a closer look at the planet and its moons over the past decades.
Extended Heat Deposition in Hot Jupiters: Application to Ohmic Heating
Ginzburg, Sivan; Sari, Re'em
2016-03-01
The observed radii of many giant exoplanets in close orbits exceed theoretical predictions. One suggested origin for this discrepancy is heat deposited deep inside the atmospheres of these “hot Jupiters”. Here, we study extended power sources that distribute heat from the photosphere to the deep interior of the planet. Our analytical treatment is a generalization of a previous analysis of localized “point sources”. We model the deposition profile as a power law in the optical depth and find that planetary cooling and contraction halt when the internal luminosity (i.e., cooling rate) of the planet drops below the heat deposited in the planet’s convective region. A slowdown in the evolutionary cooling prior to equilibrium is possible only for sources that do not extend to the planet’s center. We estimate the ohmic dissipation resulting from the interaction between the atmospheric winds and the planet’s magnetic field, and apply our analytical model to ohmically heated planets. Our model can account for the observed radii of most inflated planets, which have equilibrium temperatures of ≈1500-2500 K and are inflated to a radius of ≈ 1.6{R}J. However, some extremely inflated planets remain unexplained by our model. We also argue that ohmically inflated planets have already reached their equilibrium phase, and no longer contract. Following Wu & Lithwick, who argued that ohmic heating could only suspend and not reverse contraction, we calculate the time it takes ohmic heating to re-inflate a cold planet to its equilibrium configuration. We find that while it is possible to re-inflate a cold planet, the re-inflation timescales are longer by a factor of ≈ 30 than the cooling time.
Modeling Jupiter's Quasi Quadrennial Oscillation (QQO) with Wave Drag Parameterizations
Cosentino, Rick; Morales-Juberias, Raul; Greathouse, Thomas K.; Orton, Glenn S.
2016-10-01
The QQO in Jupiter's atmosphere was first discovered after 7.8 micron infrared observations spanning the 1980's and 1990's detected a temperature oscillation near 10 hPa (Orton et al. 1991, Science 252, 537, Leovy et. al. 1991, Nature 354, 380, Friedson 1999, Icarus 137, 34). New observations using the Texas Echelon cross-dispersed Echelle Spectrograph (TEXES), mounted on the NASA Infrared Telescope facility (IRTF), have been used to characterize a complete cycle of the QQO between January 2012 and January 2016 (Greathouse et al. 2016, DPS) . These new observations not only show the thermal oscillation at 10 hPa, but they also show that the QQO extends upwards in Jupiter's atmosphere to pressures as high as 0.4 hPa. We incorporated three different wave-drag parameterizations into the EPIC General Circulation Model (Dowling et al. 1998, Icarus 132, 221) to simulate the observed Jovian QQO temperature signatures as a function of latitude, pressure and time using results from the TEXES datasets as new constraints. Each parameterization produces unique results and offers insight into the spectra of waves that likely exist in Jupiter's atmosphere to force the QQO. High-frequency gravity waves produced from convection are extremely difficult to directly observe but likely contribute a significant portion to the QQO momentum budget. We use different models to simulate the effects of waves such as these, to indirectly explore their spectrum in Jupiter's atmosphere by varying their properties. The model temperature outputs show strong correlations to equatorial and mid-latitude temperature fields retrieved from the TEXES datasets at different epochs. Our results suggest the QQO phenomenon could be more than one alternating zonal jet that descends over time in response to Jovian atmospheric forcing (e.g. gravity waves from convection).Research funding provided by the NRAO Grote Reber Pre-Doctoral Fellowship. Computing resources include the NMT PELICAN cluster and the CISL
Radiative and dynamical modeling of Jupiter's atmosphere
Guerlet, Sandrine; Spiga, Aymeric
2016-04-01
Jupiter's atmosphere harbours a rich meteorology, with alternate westward and eastward zonal jets, waves signatures and long-living storms. Recent ground-based and spacecraft measurements have also revealed a rich stratospheric dynamics, with the observation of thermal signatures of planetary waves, puzzling meridional distribution of hydrocarbons at odds with predictions of photochemical models, and a periodic equatorial oscillation analogous to the Earth's quasi-biennal oscillation and Saturn's equatorial oscillation. These recent observations, along with the many unanswered questions (What drives and maintain the equatorial oscillations? How important is the seasonal forcing compared to the influence of internal heat? What is the large-scale stratospheric circulation of these giant planets?) motivated us to develop a complete 3D General Circulation Model (GCM) of Saturn and Jupiter. We aim at exploring the large-scale circulation, seasonal variability, and wave activity from the troposphere to the stratosphere of these giant planets. We will briefly present how we adapted our existing Saturn GCM to Jupiter. One of the main change is the addition of a stratospheric haze layer made of fractal aggregates in the auroral regions (poleward of 45S and 30N). This haze layer has a significant radiative impact by modifying the temperature up to +/- 15K in the middle stratosphere. We will then describe the results of radiative-convective simulations and how they compare to recent Cassini and ground-based temperature measurements. These simulations reproduce surprisingly well some of the observed thermal vertical and meridional gradients, but several important mismatches at low and high latitudes suggest that dynamics also plays an important role in shaping the temperature field. Finally, we will present full GCM simulations and discuss the main resulting features (waves and instabilities). We will also and discuss the impact of the choice of spatial resolution and
Tidal Response of Preliminary Jupiter Model
Wahl, Sean M.; Hubbard, William B.; Militzer, Burkhard
2016-11-01
In anticipation of improved observational data for Jupiter’s gravitational field, from the Juno spacecraft, we predict the static tidal response for a variety of Jupiter interior models based on ab initio computer simulations of hydrogen-helium mixtures. We calculate hydrostatic-equilibrium gravity terms, using the non-perturbative concentric Maclaurin Spheroid method that eliminates lengthy expansions used in the theory of figures. Our method captures terms arising from the coupled tidal and rotational perturbations, which we find to be important for a rapidly rotating planet like Jupiter. Our predicted static tidal Love number, {k}2=0.5900, is ˜10% larger than previous estimates. The value is, as expected, highly correlated with the zonal harmonic coefficient J 2, and is thus nearly constant when plausible changes are made to the interior structure while holding J 2 fixed at the observed value. We note that the predicted static k 2 might change, due to Jupiter’s dynamical response to the Galilean moons, and find reasons to argue that the change may be detectable—although we do not present here a theory of dynamical tides for highly oblate Jovian planets. An accurate model of Jupiter’s tidal response will be essential for interpreting Juno observations and identifying tidal signals from effects of other interior dynamics of Jupiter’s gravitational field.
2008-01-01
[figure removed for brevity, see original site] Click on the image for high resolution image of Nature Cover Detailed analysis of two continent-sized storms that erupted in Jupiter's atmosphere in March 2007 shows that Jupiter's internal heat plays a significant role in generating atmospheric disturbances. Understanding these outbreaks could be the key to unlock the mysteries buried in the deep Jovian atmosphere, say astronomers. This visible-light image is from NASA's Hubble Space Telescope taken on May 11, 2007. It shows the turbulent pattern generated by the two plumes on the upper left part of Jupiter. Understanding these phenomena is important for Earth's meteorology where storms are present everywhere and jet streams dominate the atmospheric circulation. Jupiter is a natural laboratory where atmospheric scientists study the nature and interplay of the intense jets and severe atmospheric phenomena. According to the analysis, the bright plumes were storm systems triggered in Jupiter's deep water clouds that moved upward in the atmosphere vi gorously and injected a fresh mixture of ammonia ice and water about 20 miles (30 kilometers) above the visible clouds. The storms moved in the peak of a jet stream in Jupiter's atmosphere at 375 miles per hour (600 kilometers per hour). Models of the disturbance indicate that the jet stream extends deep in the buried atmosphere of Jupiter, more than 60 miles (approximately100 kilometers) below the cloud tops where most sunlight is absorbed.
Modelling of Jupiter's Innermost Radiation Belt
Mihalov, J. D.; DeVincenzi, Donald (Technical Monitor)
1999-01-01
In order to understand better source and loss processes for energetic trapped protons near Jupiter, a modification of de Pater and Goertz' finite difference diffusion calculations for Jovian equatorial energetic electrons is made to apply to the case of protons inside the orbit of Metis. Explicit account is taken of energy loss in the Jovian ring. Comparison of the results is made with Galileo Probe measurements.
Atmospheric Circulation on Hot Jupiters: Modeling and Observable Signatures
Rauscher, Emily Christine
2010-12-01
Hot Jupiters are unlike any planets in our Solar System and yet one of the most common types of extrasolar planet discovered. These gas giants orbit their parent stars with periods of a few days. Expected to be tidally locked into synchronous rotation, hot Jupiters experience intense, asymmetric heating from stellar irradiation, such that day-night temperature contrasts could reach hundreds of degrees Kelvin. This unique state of radiative forcing, as well as the slow rotation rates of these planets, places hot Jupiters within a new regime of atmospheric circulation. Hot Jupiters have also been the first type of extrasolar planet with direct detections of their atmospheres, through measurements of emitted, reflected, and transmitted light. This thesis investigates observational methods to distinguish between various atmospheric models, observational signatures of potential atmospheric variability, and presents a three dimensional model with which to study hot Jupiter circulation patterns. First, we find that eclipse mapping is a technique that can be used to image the day sides of these planets and although this is beyond the ability of current instruments, it will be achievable with future missions, such as the James Webb Space Telescope. Second, we consider the signatures of large-scale atmospheric variability in measurements of secondary eclipses and thermal orbital phase curves. For various models we predict the amount of variation in eclipse depth, and the amplitudes and detailed shapes of phase curves. Lastly, we develop a three-dimensional model of hot Jupiter atmospheric dynamics with simplified forcing and adopt a set-up nearly identical to work by another group to facilitate code inter-comparison. Our results are broadly consistent with theirs, with a transonic flow and the hottest region of the atmosphere advected eastward of the substellar point. However, we note important differences and identify areas of concern for future modeling efforts.
Measuring Jupiter's water abundance by Juno: the link between interior and formation models
Helled, Ravit
2014-01-01
The JUNO mission to Jupiter is planned to measure the water abundance in Jupiter's atmosphere below the cloud layer. This measurement is important because it can be used to reveal valuable information on Jupiter's origin and its composition. In this paper we discuss the importance of this measurement, the challenges in its interpretation, and address how it can be connected to interior and formation models of Jupiter.
Brax, Philippe; Tamanini, Nicola
2016-05-01
We extend the chameleon models by considering scalar-fluid theories where the coupling between matter and the scalar field can be represented by a quadratic effective potential with density-dependent minimum and mass. In this context, we study the effects of the scalar field on Solar System tests of gravity and show that models passing these stringent constraints can still induce large modifications of Newton's law on galactic scales. On these scales we analyze models which could lead to a percent deviation of Newton's law outside the virial radius. We then model the dark matter halo as a Navarro-Frenk-White profile and explicitly find that the fifth force can give large contributions around the galactic core in a particular model where the scalar field mass is constant and the minimum of its potential varies linearly with the matter density. At cosmological distances, we find that this model does not alter the growth of large scale structures and therefore would be best tested on galactic scales, where interesting signatures might arise in the galaxy rotation curves.
The evolution of asteroids in the jumping-Jupiter migration model
Roig, Fernando
2015-01-01
In this work, we investigate the evolution of a primordial belt of asteroids, represented by a large number of massless test particles, under the gravitational effect of migrating Jovian planets in the framework of the jumping-Jupiter model. We perform several simulations considering test particles distributed in the Main Belt, as well as in the Hilda and Trojan groups. The simulations start with Jupiter and Saturn locked in the mutual 3:2 mean motion resonance plus 3 Neptune-mass planets in a compact orbital configuration. Mutual planetary interactions during migration led one of the Neptunes to be ejected in less than 10 Myr of evolution, causing Jupiter to jump by about 0.3 au in semi-major axis. This introduces a large scale instability in the studied populations of small bodies. After the migration phase, the simulations are extended over 4 Gyr, and we compare the final orbital structure of the simulated test particles to the current Main Belt of asteroids with absolute magnitude $H<9.7$. The results ...
Models of Warm Jupiter Atmospheres: Observable Signatures of Obliquity
Rauscher, Emily
2017-09-01
We present three-dimensional atmospheric circulation models of a hypothetical “warm Jupiter” planet, for a range of possible obliquities from 0° to 90°. We model a Jupiter-mass planet on a 10 day orbit around a Sun-like star, since this hypothetical planet sits at the boundary between planets for which we expect that tidal forces should have aligned their rotation axes with their orbital axes (i.e., ones with zero obliquity) and planets whose timescale for tidal alignment is longer than the typical age of an exoplanet system. In line with observational progress, which is pushing atmospheric characterization for planets on longer orbital periods, we calculate the observable signatures of obliquity for a transiting warm Jupiter: in orbital phase curves of thermal emission and in the hemispheric flux gradients that could be measured by eclipse mapping. For both of these predicted measurements, the signal that we would see depends strongly on our viewing geometry relative to the orientation of the planet’s rotation axis, and we thoroughly identify the degeneracies that result. We compare these signals to the predicted sensitivities of current and future instruments and determine that the James Webb Space Telescope should be able to constrain the obliquities of nearby warm Jupiters to be small (if ≤slant 10^\\circ ) or to directly measure them if significantly non-zero (≥slant 30^\\circ ) using the technique of eclipse mapping. For a bright target and assuming photon-limited precision, this could be done with a single secondary eclipse observation.
Extending reference assembly models
DEFF Research Database (Denmark)
Church, Deanna M.; Schneider, Valerie A.; Steinberg, Karyn Meltz
2015-01-01
The human genome reference assembly is crucial for aligning and analyzing sequence data, and for genome annotation, among other roles. However, the models and analysis assumptions that underlie the current assembly need revising to fully represent human sequence diversity. Improved analysis tools...
Extending reference assembly models
DEFF Research Database (Denmark)
Church, Deanna M.; Schneider, Valerie A.; Steinberg, Karyn Meltz;
2015-01-01
The human genome reference assembly is crucial for aligning and analyzing sequence data, and for genome annotation, among other roles. However, the models and analysis assumptions that underlie the current assembly need revising to fully represent human sequence diversity. Improved analysis tools...
THE EVOLUTION OF ASTEROIDS IN THE JUMPING-JUPITER MIGRATION MODEL
Energy Technology Data Exchange (ETDEWEB)
Roig, Fernando [Observatòrio Nacional, Rua Gal. Jose Cristino 77, Rio de Janeiro, RJ 20921-400 (Brazil); Nesvorný, David, E-mail: froig@on.br, E-mail: davidn@boulder.swri.edu [Southwest Research Institute, 1050 Walnut St., Suite 300, Boulder, CO 80302 (United States)
2015-12-15
In this work, we investigate the evolution of a primordial belt of asteroids, represented by a large number of massless test particles, under the gravitational effect of migrating Jovian planets in the framework of the jumping-Jupiter model. We perform several simulations considering test particles distributed in the Main Belt, as well as in the Hilda and Trojan groups. The simulations start with Jupiter and Saturn locked in the mutual 3:2 mean motion resonance plus three Neptune-mass planets in a compact orbital configuration. Mutual planetary interactions during migration led one of the Neptunes to be ejected in less than 10 Myr of evolution, causing Jupiter to jump by about 0.3 AU in semimajor axis. This introduces a large-scale instability in the studied populations of small bodies. After the migration phase, the simulations are extended over 4 Gyr, and we compare the final orbital structure of the simulated test particles to the current Main Belt of asteroids with absolute magnitude H < 9.7. The results indicate that, in order to reproduce the present Main Belt, the primordial belt should have had a distribution peaked at ∼10° in inclination and at ∼0.1 in eccentricity. We discuss the implications of this for the Grand Tack model. The results also indicate that neither primordial Hildas, nor Trojans, survive the instability, confirming the idea that such populations must have been implanted from other sources. In particular, we address the possibility of implantation of Hildas and Trojans from the Main Belt population, but find that this contribution should be minor.
Transmission Spectra of Three-Dimensional Hot Jupiter Model Atmospheres
Fortney, J J; Showman, A P; Lian, Y; Freedman, R S; Marley, M S; Lewis, N K
2009-01-01
We compute models of the transmission spectra of planets HD 209458b, HD 189733b, and generic hot Jupiters. We examine the effects of temperature, surface gravity, and metallicity for the generic planets as a guide to understanding transmission spectra in general. We find that carbon dioxide absorption at 4.4 and 15 microns is prominent at high metallicity, and is a clear metallicity indicator. For HD 209458b and HD 189733b, we compute spectra for both one-dimensional and three-dimensional model atmospheres and examine the differences between them. The differences are usually small, but can be large if atmospheric temperatures are near important chemical abundance boundaries. The calculations for the 3D atmospheres, and their comparison with data, serve as constraints on these dynamical models that complement the secondary eclipse and light curve data sets. For HD 209458b, even if TiO and VO gases are abundant on the day side, their abundances can be considerably reduced on the cooler planetary limb. However, ...
The open-source, public domain JUPITER (Joint Universal Parameter IdenTification and Evaluation of Reliability) API (Application Programming Interface) provides conventions and Fortran-90 modules to develop applications (computer programs) for analyzing process models. The input ...
Working model of the atmosphere and near planetary space of Jupiter
Moroz, V. I. (Editor)
1978-01-01
Basic physical characteristics of Jupiter, its gravitational field, atmosphere, electromagnetic radiation, magnetosphere, meteorite situation and satellites are presented in tables, graphs and figures. Means of observation of the atmosphere and three models of the atmosphere are presented and analyzed.
Magnetospheres of hot Jupiters: hydrodynamic models & ultraviolet absorption
Alexander, R D; Mohammed, H; Nichols, J D; Ercolano, B
2015-01-01
We present hydrodynamic simulations of stellar wind-magnetosphere interactions in hot Jupiters such as WASP-12b. For fiducial stellar wind rates we find that a planetary magnetic field of a few G produces a large magnetospheric cavity, which is typically 6-9 planetary radii in size. A bow shock invariably forms ahead of the magnetosphere, but the pre-shock gas is only mildly supersonic (with typical Mach numbers of $\\simeq$1.6-1.8) so the shock is weak. This results in a characteristic signature in the ultraviolet light curve: a broad absorption feature that leads the optical transit by 10-20% in orbital phase. The shapes of our synthetic light-curves are consistent with existing observations of WASP-12b, but the required near-UV optical depth ($\\tau \\sim 0.1$) can only be achieved if the shocked gas cools rapidly. We further show that radiative cooling is inefficient, so we deem it unlikely that a magnetospheric bow shock is responsible for the observed near-UV absorption. Finally, we apply our model to two ...
Extended UML with Role Modeling
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
UML is widely accepted and applied by the international softwareindus try. UML is a powerful language for Object-oriented modeling, designing, and i m plementing software systems, but its Use-Case method for requirement analysis a n d modeling software patterns has some explicit drawbacks. For more complete UML, this paper proposes the Role Use-Case modeling and its glyphs, and provides an instance of requirement analysis using Role Use-Case method. Uses the Role Mode l to modeling software pattern at knowledge level. This paper also extends the UM L Meta Model and accentuates “RM before UML's class Modeling”.
Jupiter Eruptions Captured in Infrared
2008-01-01
[figure removed for brevity, see original site] Click on the image for high resolution image of Nature Cover Detailed analysis of two continent-sized storms that erupted in Jupiter's atmosphere in March 2007 shows that Jupiter's internal heat plays a significant role in generating atmospheric disturbances. Understanding these outbreaks could be the key to unlock the mysteries buried in the deep Jovian atmosphere, say astronomers. This infrared image shows two bright plume eruptions obtained by the NASA Infrared Telescope Facility on April 5, 2007. Understanding these phenomena is important for Earth's meteorology where storms are present everywhere and jet streams dominate the atmospheric circulation. Jupiter is a natural laboratory where atmospheric scientists study the nature and interplay of the intense jets and severe atmospheric phenomena. According to the analysis, the bright plumes were storm systems triggered in Jupiter's deep water clouds that moved upward in the atmosphere vigorously and injected a fresh mixture of ammonia ice and water about 20 miles (30 kilometers) above the visible clouds. The storms moved in the peak of a jet stream in Jupiter's atmosphere at 375 miles per hour (600 kilometers per hour). Models of the disturbance indicate that the jet stream extends deep in the buried atmosphere of Jupiter, more than 60 miles (approximately100 kilometers) below the cloud tops where most sunlight is absorbed.
The Jupiter ONERA Electron (JOE) and Jupiter ONERA Proton (JOP) specification models
Bourdarie, , S.; Sicard-Piet, A.
2008-09-01
The use of recent improvement in the understanding of the Jovian radiation belt structure has allowed to develop a more accurate engineering model of the Jovian electron and proton radiation belts. The basic idea was to combine the results of the Salammbô code when available (for proton and electron species) with the Divine and Garret model 1983 and/or with GIRE. The advantage of such an approach was that the resulting model is global in term of spatial and energy coverage, is optimised inside Europa orbit (the Divine and Garret model is not accurate inside Io orbit due to poor in-situ data there - note that inside Io is the region where ionizing radiation fluxes are maximum) and take advantage of the two models. The resulting JOE-JOP models will be presented, pro and cons will be listed and commented. Finally future plans to upgrade these models will be given.
A Model of Jupiter's Decametric Radio Emissions as a Searchlight Beam
Imai, K.; Garcia, L.; Reyes, F.; Imai, M.; Thieman, J. R.
It has long been recognized that there is a marked long-term periodic variation in Jupiter's integrated radio occurrence probability. The period of the variation is on the order of a decade. Carr et al. [1970] showed that such variations are closely correlated with Jovicentric declination of the Earth (DE). The range of the smoothed variation of DE is from approximately +3.3 to -3.3 degrees. This DE effect was extensively studied and confirmed by Garcia [1996]. It shows that the occurrence probability of the non-Io-A source is clearly controlled by DE at 18, 20, and 22 MHz during the 1957-1994 apparitions. We propose a new model to explain the DE effect. This new model shows that the beam structure of Jupiter radio emissions, which has been thought of like a hollow-cone, has a narrow beam like a searchlight, which can be explained by assuming that the three dimensional shape of the radio source expands along the line of the magnetic field. If we consider the sizes of the radio coherent region are 1000 m along Jupiter's magnetic field line and 200 m along the latitudinal direction, the equivalent beam pattern is 1 degree wide along Jupiter's magnetic field line and 5 degrees in latitude. As the searchlight beam is fixed with Jupiter's magnetic field, the pure geometrical effect of DE can be explained by this searchlight beam model.
Bayesian Evolution Models for Jupiter with Helium Rain and Double-diffusive Convection
Mankovich, Christopher; Moore, Kevin L
2016-01-01
Hydrogen and helium demix when sufficiently cool, and this bears on the evolution of all giant planets at large separations at or below roughly a Jupiter mass. We model the thermal evolution of Jupiter, including its evolving helium distribution following results of ab initio simulations for helium immiscibility in metallic hydrogen. After 4 Gyr of homogeneous evolution, differentiation establishes a thin helium gradient below 1 Mbar that dynamically stabilizes the fluid to convection. The region undergoes overstable double-diffusive convection (ODDC), whose weak heat transport maintains a superadiabatic temperature gradient. With a generic parameterization for the ODDC efficiency, the models can reconcile Jupiter's intrinsic flux, atmospheric helium content, and radius at the age of the solar system if the Lorenzen et al. H-He phase diagram is translated to lower temperatures. We cast the evolutionary models in an MCMC framework to explore tens of thousands of evolutionary sequences, retrieving probability d...
Gas dynamic modeling of the CME propagation through the envelope of a hot Jupiter-type exoplanet
Cherenkov, A. A.; Kaygorodov, P. V.; Bisikalo, D. V.
2016-05-01
We propose a 3D gasdynamic numerical model for the study of the interaction between the extended envelopes of hot Jupiters, overfilling their Roche lobes, and non-stationary stellar wind. In the model we use a Roe-Osher numerical scheme with Eindfeldt entropy fix. To test the model we have simulated a flow structure, forming due to the interaction between the extended quasi-stationary envelope of the hot Jupiter planet HD 209458b and the bow shock formed ahead of a propagating coronal mass ejection (CME). We have adopted the solar CME parameters in our computations and taken into account the fact that the planet is located close to its host star. The simulation results show that the bow shock of the CME partially destroys the stream, starting from the Li point of the quasi-closed planet's envelope. A bow shock, existing ahead of the planet in its orbital motion when the stellar wind is undisturbed, almost disappears when the CME shock passes through the system.
Numerical Modeling of the 2009 Impact Event on Jupiter
Pond, Jarrad W T; Gabriel, Travis; Korycansky, Donald G; Harrington, Joseph; Rebeli, Noemi; 10.1088/0004-637X/745/2/113
2012-01-01
We have investigated the 2009 July impact event on Jupiter using the ZEUS-MP 2 three-dimensional hydrodynamics code. We studied the impact itself and the following plume development. Eight impactors were considered: 0.5 km and 1 km porous (\\rho = 1.760 g cm^{-3}) and non-porous (\\rho = 2.700 g cm^{-3}) basalt impactors, and 0.5 km and 1 km porous (\\rho = 0.600 g cm^{-3}) and non-porous \\rho = 0.917 g cm^{-3}) ice impactors. The simulations consisted of these bolides colliding with Jupiter at an incident angle of \\theta = 69 degrees from the vertical and with an impact velocity of v = 61.4 km s^{-1}. Our simulations show the development of relatively larger, faster plumes created after impacts involving 1 km diameter bodies. Comparing simulations of the 2009 event with simulations of the Shoemaker-Levy 9 events reveals a difference in plume development, with the higher incident angle of the 2009 impact leading to a shallower terminal depth and a smaller and slower plume. We also studied the amount of dynamical...
Dicyanometallates as Model Extended Frameworks
2016-01-01
We report the structures of eight new dicyanometallate frameworks containing molecular extra-framework cations. These systems include a number of hybrid inorganic–organic analogues of conventional ceramics, such as Ruddlesden–Popper phases and perovskites. The structure types adopted are rationalized in the broader context of all known dicyanometallate framework structures. We show that the structural diversity of this family can be understood in terms of (i) the charge and coordination preferences of the particular metal cation acting as framework node, and (ii) the size, shape, and extent of incorporation of extra-framework cations. In this way, we suggest that dicyanometallates form a particularly attractive model family of extended frameworks in which to explore the interplay between molecular degrees of freedom, framework topology, and supramolecular interactions. PMID:27057759
Jupiter models with improved ab initio hydrogen EOS (H-REOS.2)
Nettelmann, Nadine; Holst, Bastian; Redmer, Ronald
2011-01-01
The amount and distribution of heavy elements in Jupiter gives indications on the process of its formation and evolution. Core mass and metallicity predictions however depend on the equations of state used, and on model assumptions. We present an improved ab initio hydrogen equation of state, H-REOS.2 and compute the internal structure and thermal evolution of Jupiter within the standard three-layer approach. The advance over comparable previous Jupiter models (Nettelmann et al. 2008, ApJ 683, 1217) is that the new models are also consistent with the observed \\gtrsim 2 times solar heavy element abundances in Jupiter's atmosphere. Such models have a rock core mass Mcore=0-8 ME, total mass of heavy elements MZ=28-31 ME, a deep internal layer boundary at \\geq 4 Mbar, and a cooling time of 4.7 Gyrs when assuming homogeneous evolution. We also calculate two-layer models in the manner of Militzer et al. (2008), ApJ 688, L45, and find a comparable core mass but significantly higher envelope metallicity of 4.5 times ...
Heimpel, Moritz; Aurnou, Jonathan
2007-04-01
The origin of zonal jets on the jovian planets has long been a topic of scientific debate. In this paper we show that deep convection in a spherical shell can generate zonal flow comparable to that observed on Jupiter and Saturn, including a broad prograde equatorial jet and multiple alternating jets at higher latitudes. We present fully turbulent, 3D spherical numerical simulations of rapidly rotating convection with different spherical shell geometries. The resulting global flow fields tend to be segregated into three regions (north, equatorial, and south), bounded by the tangent cylinder that circumscribes the inner boundary equator. In all of our simulations a strong prograde equatorial jet forms outside the tangent cylinder, whereas multiple jets form in the northern and southern hemispheres, inside the tangent cylinder. The jet scaling of our numerical models and of Jupiter and Saturn is consistent with the theory of geostrophic turbulence, which we extend to include the effect of spherical shell geometry. Zonal flow in a spherical shell is distinguished from that in a full sphere or a shallow layer by the effect of the tangent cylinder, which marks a reversal in the sign of the planetary β-parameter and a jump in the Rhines length. This jump is manifest in the numerical simulations as a sharp equatorward increase in jet widths—a transition that is also observed on Jupiter and Saturn. The location of this transition gives an estimate of the depth of zonal flow, which seems to be consistent with current models of the jovian and saturnian interiors.
An integrated model for Jupiter's dynamo action and mean jet dynamics
Gastine, Thomas; Wicht, Johannes; Duarte, Lucia; Heimpel, Moritz
2014-05-01
Data from various space crafts revealed that Jupiter's large scale interior magnetic field is very Earth-like. This is surprising since numerical simulations have demonstrated that, for example, the radial dependence of density, electrical conductivity and other physical properties, which is only mild in the iron cores of terrestrial planets but very drastic in gas planets, can significantly affect the interior dynamics. Jupiter's dynamo action is thought to take place in the deeper envelope where hydrogen, the main constituent of Jupiter's atmosphere, assumes metallic properties. The potential interaction between the observed zonal jets and the deeper dynamo region is an unresolved problem with important consequences for the magnetic field generation. Here we present the first numerical simulation that is based on recent interior models and covers 99% of the planetary radius (below the 1 bar level). A steep decease in the electrical conductivity over the outer 10% in radius allowed us to model both the deeper metallic region and the outer molecular layer in an integrated approach. The magnetic field very closely reproduces Jupiter's known large scale field. A strong equatorial zonal jet remains constrained to the molecular layer while higher latitude jets are suppressed by Lorentz forces. This suggests that Jupiter's higher latitude jets remain shallow and are driven by an additional effect not captured in our deep convection model. The dynamo action of the equatorial jet produces a band of magnetic field located around the equator. The unprecedented magnetic field resolution expected from the Juno mission will allow to resolve this feature allowing a direct detection of the equatorial jet dynamics at depth. Typical secular variation times scales amount to around 750 yr for the dipole contribution but decrease to about 5 yr at the expected Juno resolution (spherical harmonic degree 20). At a nominal mission duration of one year Juno should therefore be able to
5-Dimensional Extended Space Model
Tsipenyuk, D. Yu.; Andreev, V. A.
2006-01-01
We put forward an idea that physical phenomena have to be treated in 5-dimensional space where the fifth coordinate is the interval S. Thus, we considered the (1+4) extended space G(T;X,Y,Z,S). In addition to Lorentz transformations (T;X), (T;Y), (T;Z) which are in (1+3)-dimensional Minkowski space, in the proposed (1+4)d extended space two other types of transformations exist in planes (T,S); (X,S), (Y,S), (Z,S) that converts massive particles into massless and vice versa. We also consider e...
3D modeling of lightning-induced electromagnetic pulses on Venus, Jupiter and Saturn
Pérez-Invernón, Francisco J.; Luque, Alejandro; Gordillo-Vázquez, Francisco J.
2017-04-01
Atmospheric electricity is a common phenomenon in some planets of The Solar System. We know that atmospheric discharges exist on Earth and gaseous planets; however, some characteristics of lightning on Saturn and Jupiter as well as their relevance on the effects of lightning in the atmospheres of these planets are still unknown. In the case of Venus, there exist some radio evidences of lightning, but the lack of optical observations suggests exploring indirect methods of detection, such as searching for lightning-induced transient optical emissions from the upper atmosphere. The Akatsuki probe, currently orbiting Venus, is equipped with a camera whose temporal resolution is high enough to detect optical emissions from lightning discharges and to measure nightglow enhancements. In this work, we extend previous models [1,2] to investigate the chemical impact and transient optical emissions produced by possible lightning-emitted electromagnetic pulses (EMP) in Venus, Saturn and Jupiter. Using a 3D FDTD ("Finite Differences Time Domain") model we solve the Maxwell equations coupled with the Langevin equation for electrons [3] and with a kinetic scheme, different for each planetary atmosphere. This method is useful to investigate the temporal and spatial impact of lightning-induced electromagnetic fields in the atmosphere of each planet for different lightning characteristics (e.g. energy released, orientation). This 3D FDTD model allows us to include the saturnian and jovian background magnetic field inclination and magnitude at different latitudes, and to determine the effects of different lightning channel inclinations. Results provide useful information to interpret lightning observations on giant gaseous planets and in the search for indirect optical signals from atmospheric discharge on Venus such as fast nightglow transient enhancements related to lightning as seen on Earth. Furthermore, we underline the observation of electrical discharges characteristics as a
Simulation of equatorial and high-latitude jets on Jupiter in a deep convection model.
Heimpel, Moritz; Aurnou, Jonathan; Wicht, Johannes
2005-11-10
The bands of Jupiter represent a global system of powerful winds. Broad eastward equatorial jets are flanked by smaller-scale, higher-latitude jets flowing in alternating directions. Jupiter's large thermal emission suggests that the winds are powered from within, but the zonal flow depth is limited by increasing density and electrical conductivity in the molecular hydrogen-helium atmosphere towards the centre of the planet. Two types of planetary flow models have been explored: shallow-layer models reproduce multiple high-latitude jets, but not the equatorial flow system, and deep convection models only reproduce an eastward equatorial jet with two flanking neighbours. Here we present a numerical model of three-dimensional rotating convection in a relatively thin spherical shell that generates both types of jets. The simulated flow is turbulent and quasi-two-dimensional and, as observed for the jovian jets, simulated jet widths follow Rhines' scaling theory. Our findings imply that Jupiter's latitudinal transition in jet width corresponds to a separation between the bottom-bounded flow structures in higher latitudes and the deep equatorial flows.
Modeling the Neutral Gas and Plasma Environment of Jupiter's Moon Europa
Rubin, Martin; Tenishev, Valeriy; Hansen, Kenneth; Jia, Xianzhe; Combi, Michael; Gombosi, Tamas
Jupiter's moon Europa has a thin gravitationally bound neutral atmosphere, which is mostly created through sputtering of high-energy ions impacting on its icy surface. The interaction of Europa with the Jovian magnetosphere is simulated using the magnetohydrodynamics (MHD) model BATSRUS. We start from the model by Kabin et al. [JGR, Vol. 104, No. A9, (1999)], which accounts for the exospheric mass loading, ion-neutral charge exchange, and ion-electron recombination. The derived magnetic field topology and plasma speeds are used to calculate the Lorentz force for our test particle Monte Carlo model. We use this model to simulate Europa's plasma and neutral environment by tracking particles created on the moon's surface by sputtering or sublimation, through dissociation and/or ionization in the atmosphere, or entering the system from Jupiter's magnetosphere as high energy ions. Neutral particle trajectories are followed by solving the equation of motion in Europa's gravity field whereas the ion population is additionally subject to the Lorentz force. We will show preliminary results of this work with application to the missions to the Jupiter system currently under consideration by NASA (JEO) and ESA (JGO).
Visscher, Channon; Saslow, Sarah A
2010-01-01
We have developed a one-dimensional thermochemical kinetics and diffusion model for Jupiter's atmosphere that accurately describes the transition from the thermochemical regime in the deep troposphere (where chemical equilibrium is established) to the quenched regime in the upper troposphere (where chemical equilibrium is disrupted). The model is used to calculate chemical abundances of tropospheric constituents and to identify important chemical pathways for CO-CH4 interconversion in hydrogen-dominated atmospheres. In particular, the observed mole fraction and chemical behavior of CO is used to indirectly constrain the Jovian water inventory. Our model can reproduce the observed tropospheric CO abundance provided that the water mole fraction lies in the range (0.25-6.0) x 10^-3 in Jupiter's deep troposphere, corresponding to an enrichment of 0.3 to 7.3 times the protosolar abundance (assumed to be H2O/H2 = 9.61 x 10^-4). Our results suggest that Jupiter's oxygen enrichment is roughly similar to that for carb...
The role of Io in the dynamics of Jupiter's magnetosphere: A sandpile modelling approach.
Reed, J. J.; Jackman, C. M.; Freeman, M. P.
2015-10-01
Jupiter's magnetosphere is thought to be largely internally driven, by the combination of the loading of ~500 kg/s of plasma into the system by the volcanic moon Io, and the rapid rotation of the planet itself. Since we do not see a continuously expanding torus and magnetosphere, we would expect a long-term balance between the inflow of mass, primarily from Io, and the outflow of mass, via plasmoid release. Simple calculations, which attempt to match the mass-loading rate from Io with the amount of mass lost via large-scale tail reconnection events, indicate a significant mass imbalance at Jupiter. This mass imbalance may be due to several reasons, including visibility issues linked to single spacecraft observations. This is where modelling can be a powerful tool. A single spacecraft can only expect to observe a global 'systemwide' event, where energy is redistributed across the entiresystem, with any certainty. While 'internal' events, with a more local redistribution of energy, are likely to be missed. Usingcomputational modeling we are able to'observe' an entire system at any time. Cellular automata (CA) based on robust physical parameters and rules can allow us to manipulate the inputs and drivers of magnetotail physics, and to explore the response of the system over a range of temporal and spatial scales. Here we examine the variability of the mass-loading and the response of our CA sandpile model to an analogous driving. We explore whether Jupiter's magnetospheric dynamics can be explained purely in terms of Io massloading. In particular we examine the difference between the small local events ("internal" avalanches) and larger global events ("systemwide" avalanches), and what this can tell us about the fate of mass in Jupiter's magnetosphere.
Extending models for two-dimensional constraints
DEFF Research Database (Denmark)
Forchhammer, Søren
2009-01-01
Random fields in two dimensions may be specified on 2 times 2 elements such that the probabilities of finite configurations and the entropy may be calculated explicitly. The Pickard random field is one example where probability of a new (non-boundary) element is conditioned on three previous...... elements. To extend the concept we consider extending such a field such that a vector or block of elements is conditioned on a larger set of previous elements. Given a stationary model defined on 2 times 2 elements, iterative scaling is used to define the extended model. The extended model may be used...
Accuracy tests of radiation schemes used in hot Jupiter Global Circulation Models
Amundsen, David Skålid; Tremblin, Pascal; Manners, James; Hayek, Wolfgang; Mayne, N J; Acreman, David M
2014-01-01
The treatment of radiation transport in global circulation models (GCMs) is crucial to correctly describe Earth and exoplanet atmospheric dynamics processes. The two-stream approximation and correlated-$k$ method are currently state-of-the-art approximations applied in both Earth and hot Jupiter GCM radiation schemes to facilitate rapid calculation of fluxes and heating rates. Their accuracy have been tested extensively for Earth-like conditions, but verification of the methods' applicability to hot Jupiter-like conditions is lacking in the literature. We are adapting the UK Met Office GCM, the Unified Model (UM), for the study of hot Jupiters, and present in this work the adaptation of the Edwards-Slingo radiation scheme based on the two-stream approximation and the correlated-$k$ method. We discuss the calculation of absorption coefficients from high temperature line lists and highlight the large uncertainty in the pressure-broadened line widths. We compare fluxes and heating rates obtained with our adapted...
Accuracy tests of radiation schemes used in hot Jupiter global circulation models
Amundsen, David S.; Baraffe, Isabelle; Tremblin, Pascal; Manners, James; Hayek, Wolfgang; Mayne, Nathan J.; Acreman, David M.
2014-04-01
The treatment of radiation transport in global circulation models (GCMs) is crucial for correctly describing Earth and exoplanet atmospheric dynamics processes. The two-stream approximation and correlated-k method are currently state-of-the-art approximations applied in both Earth and hot Jupiter GCM radiation schemes to facilitate the rapid calculation of fluxes and heating rates. Their accuracy have been tested extensively for Earth-like conditions, but verification of the methods' applicability to hot Jupiter-like conditions is lacking in the literature. We are adapting the UK Met Office GCM, the Unified Model (UM), for the study of hot Jupiters, and present in this work the adaptation of the Edwards-Slingo radiation scheme based on the two-stream approximation and the correlated-k method. We discuss the calculation of absorption coefficients from high-temperature line lists and highlight the large uncertainty in the pressure-broadened line widths. We compare fluxes and heating rates obtained with our adapted scheme to more accurate discrete ordinate (DO) line-by-line (LbL) calculations ignoring scattering effects. We find that, in most cases, errors stay below 10% for both heating rates and fluxes using ~10 k-coefficients in each band and a diffusivity factor D = 1.66. The two-stream approximation and the correlated-k method both contribute non-negligibly to the total error. We also find that using band-averaged absorption coefficients, which have previously been used in radiative-hydrodynamical simulations of a hot Jupiter, may yield errors of ~100%, and should thus be used with caution.
An ice crystal model for jupiter's moon Europa
DEFF Research Database (Denmark)
Dahl-Jensen, Dorthe; schmidt, Karen Guldbae
2003-01-01
A simple model for crystal growth in the ice shell of Europa has been made in order to estimate the size of ice crystals at Europa's surface. If mass is lost from the surface of Europa due to sputtering processes, and the ice thickness is constant in time, ice crystals will be transported upwards...... in the ice shell. The crystals will therefore grow under varying conditions through the shell.The model predicts that ice crystals are 4 cm-80 m across at the surface. For the preferred parameter values, a crystal size of the order of 7 m is calculated. Udgivelsesdato: 1 june...
An Extended Analysis of Requirements Traceability Model
Institute of Scientific and Technical Information of China (English)
Jiang Dandong(蒋丹东); Zhang Shensheng; Chen Lu
2004-01-01
A new extended meta model of traceability is presented. Then, a formalized fine-grained model of traceability is described. Some major issues about this model, including trace units, requirements and relations within the model, are further analyzed. Finally, a case study that comes from a key project of 863 Program is given.
Characterising and modelling extended conducted electromagnetic emission
CSIR Research Space (South Africa)
Grobler, Inus
2013-06-01
Full Text Available -1 2013 IEEE Energy Conversion Congress and Exposition Asia (ECCE Downunder), Melbourne, Australia, 3-6 June 2013 Characterising and Modelling Extended Conducted Electromagnetic Emission I Grobler1 and MN Gitau2 Department of Electrical...
Sturm, Erick J.; Monahue, Kenneth M.; Biehl, James P.; Kokorowski, Michael; Ngalande, Cedrick,; Boedeker, Jordan
2012-01-01
The Jupiter Environment Tool (JET) is a custom UI plug-in for STK that provides an interface to Jupiter environment models for visualization and analysis. Users can visualize the different magnetic field models of Jupiter through various rendering methods, which are fully integrated within STK s 3D Window. This allows users to take snapshots and make animations of their scenarios with magnetic field visualizations. Analytical data can be accessed in the form of custom vectors. Given these custom vectors, users have access to magnetic field data in custom reports, graphs, access constraints, coverage analysis, and anywhere else vectors are used within STK.
An Extended Chiral SU(3) Quark Model
Institute of Scientific and Technical Information of China (English)
ZHANG Zong-Ye; YU You-Wen; WANG Ping; DAI Lian-Rong
2003-01-01
The chiral SU(3) quark model is extended by including the vector meson exchanges to describe the short range interactions. The phase shifts of NN scattering are studied in this model. Compared with the results of the chiral SU(3) quark model in which only the pseudo-scalar and scalar chiralfields are considered, the phase shifts of 1 So wave are obviously improved.
Banta, Edward R.; Poeter, Eileen P.; Doherty, John E.; Hill, Mary C.
2006-01-01
The Joint Universal Parameter IdenTification and Evaluation of Reliability Application Programming Interface (JUPITER API) improves the computer programming resources available to those developing applications (computer programs) for model analysis. The JUPITER API consists of eleven Fortran-90 modules that provide for encapsulation of data and operations on that data. Each module contains one or more entities: data, data types, subroutines, functions, and generic interfaces. The modules do not constitute computer programs themselves; instead, they are used to construct computer programs. Such computer programs are called applications of the API. The API provides common modeling operations for use by a variety of computer applications. The models being analyzed are referred to here as process models, and may, for example, represent the physics, chemistry, and(or) biology of a field or laboratory system. Process models commonly are constructed using published models such as MODFLOW (Harbaugh et al., 2000; Harbaugh, 2005), MT3DMS (Zheng and Wang, 1996), HSPF (Bicknell et al., 1997), PRMS (Leavesley and Stannard, 1995), and many others. The process model may be accessed by a JUPITER API application as an external program, or it may be implemented as a subroutine within a JUPITER API application . In either case, execution of the model takes place in a framework designed by the application programmer. This framework can be designed to take advantage of any parallel processing capabilities possessed by the process model, as well as the parallel-processing capabilities of the JUPITER API. Model analyses for which the JUPITER API could be useful include, for example: * Compare model results to observed values to determine how well the model reproduces system processes and characteristics. * Use sensitivity analysis to determine the information provided by observations to parameters and predictions of interest. * Determine the additional data needed to improve selected
Integrable extended van der Waals model
Giglio, Francesco; Landolfi, Giulio; Moro, Antonio
2016-10-01
Inspired by the recent developments in the study of the thermodynamics of van der Waals fluids via the theory of nonlinear conservation laws and the description of phase transitions in terms of classical (dissipative) shock waves, we propose a novel approach to the construction of multi-parameter generalisations of the van der Waals model. The theory of integrable nonlinear conservation laws still represents the inspiring framework. Starting from a macroscopic approach, a four parameter family of integrable extended van der Waals models is indeed constructed in such a way that the equation of state is a solution to an integrable nonlinear conservation law linearisable by a Cole-Hopf transformation. This family is further specified by the request that, in regime of high temperature, far from the critical region, the extended model reproduces asymptotically the standard van der Waals equation of state. We provide a detailed comparison of our extended model with two notable empirical models such as Peng-Robinson and Soave's modification of the Redlich-Kwong equations of state. We show that our extended van der Waals equation of state is compatible with both empirical models for a suitable choice of the free parameters and can be viewed as a master interpolating equation. The present approach also suggests that further generalisations can be obtained by including the class of dispersive and viscous-dispersive nonlinear conservation laws and could lead to a new type of thermodynamic phase transitions associated to nonclassical and dispersive shock waves.
Wang, Dong; Mousis, Olivier
2016-01-01
Disequilibrium species have been used previously to probe the deep water abundances and the eddy diffusion coefficient for giant planets. In this paper, we present a diffusion-kinetics code that predicts the abundances of disequilibrium species in the tropospheres of Jupiter and Saturn with updated thermodynamic and kinetic data. The dependence on the deep water abundance and the eddy diffusion coefficient is investigated. We quantified the disagreements in CO kinetics that comes from using different reaction networks and identified C$_2$H$_6$ as a useful tracer for the eddy diffusion coefficient. We first apply a H/P/O reaction network to Jupiter and Saturn's atmospheres and suggest a new PH$_3$ destruction pathway. New chemical pathways for SiH$_4$ and GeH$_4$ destruction are also suggested, and another AsH$_3$ destruction pathway is investigated thanks to new thermodynamic and kinetic data. These new models should enhance the interpretation of the measurement of disequilibrium species by JIRAM on board Jun...
Wang, D.; Lunine, J. I.; Mousis, O.
2016-12-01
Disequilibrium species have been used previously to probe the deep water abundances and the eddy diffusion coefficient for giant planets. In this abstract, we present a diffusion-kinetics code that predicts the abundances of disequilibrium species in the tropospheres of Jupiter and Saturn with updated thermodynamic and kinetic data. The dependence on the deep water abundance and the eddy diffusion coefficient is investigated. We quantified the disagreements in CO kinetics that comes from using different reaction networks and identified C2H6 as a useful tracer for the eddy diffusion coefficient. We first apply an H/P/O reaction network to Jupiter and Saturn's atmospheres and suggest a new PH3 destruction pathway. New chemical pathways for SiH4 and GeH4 destruction are also suggested, and another AsH3 destruction pathway is investigated thanks to new thermodynamic and kinetic data. These new models should enhance the interpretation of the measurement of disequilibrium species by JIRAM on board Juno and allow disentangling between methods for constraining the Saturn's deep water abundance with the Saturn entry probes envisaged by NASA or ESA.
Mankovich, Christopher; Fortney, Jonathan J.; Nettelmann, Nadine; Moore, Kevin
2016-10-01
Hydrogen and helium unmix when sufficiently cool, and this bears on the thermal evolution of all cool giant planets at or below one Jupiter mass. Over the past few years, ab initio simulations have put us in the era of quantitative predictions for this H-He immiscibility at megabar pressures. We present models for the thermal evolution of Jupiter, including its evolving helium distribution following one such ab initio H-He phase diagram. After 4 Gyr of homogeneous evolution, differentiation establishes a helium gradient between 1 and 2 Mbar that dynamically stabilizes the fluid to overturning convection. The result is a region undergoing overstable double-diffusive convection (ODDC), whose relatively weak vertical heat transport maintains a superadiabatic temperature gradient. With a general parameterization for the ODDC efficiency, the models can reconcile Jupiter's intrinsic flux, atmospheric helium content, and mean radius at the age of the solar system if the H-He phase diagram is translated to cooler temperatures.We cast our nonadiabatic thermal evolution models in a Markov chain Monte Carlo parameter estimation framework, retrieving the total heavy element mass, the superadiabaticity of the deep temperature gradient, and the phase diagram temperature offset. Models using the interpolated Saumon, Chabrier and van Horn (1995) equation of state (SCvH-I) favor very inefficient ODDC such that the deep temperature gradient is strongly superadiabatic, forming a thermal boundary layer that allows the molecular envelope to cool quickly while the deeper interior (most of the planet's mass) actually heats up over time. If we modulate the overall cooling time with an additional free parameter, mimicking the effect of a colder or warmer EOS, the models favor those that are colder than SCvH-I; this class of EOS is also favored by shock experiments. The models in this scenario have more modest deep superadiabaticities such that the envelope cools more gradually and the deep
Exploring Social Structures in Extended Team Model
DEFF Research Database (Denmark)
Zahedi, Mansooreh; Ali Babar, Muhammad
2013-01-01
Extended Team Model (ETM) as a type of offshore outsourcing is increasingly becoming popular mode of Global Software Development (GSD). There is little knowledge about the social structures in ETM and their impact on collaboration. Within a large interdisciplinary project to develop the next gene...
3D Modeling of Spectra and Light Curves of Hot Jupiters with PHOENIX; a First Approach
Jiménez-Torres, J. J.
2016-04-01
A detailed global circulation model was used to feed the PHOENIX code and calculate 3D spectra and light curves of hot Jupiters. Cloud free and dusty radiative fluxes for the planet HD179949b were modeled to show differences between them. The PHOENIX simulations can explain the broad features of the observed 8 μm light curves, including the fact that the planet-star flux ratio peaks before the secondary eclipse. The PHOENIX reflection spectrum matches the Spitzer secondary-eclipse depth at 3.6 μm and underpredicts eclipse depths at 4.5, 5.8 and 8.0 μm. These discrepancies result from the chemical composition and suggest the incorporation of different metallicities in future studies.
3D MODELING OF SPECTRA AND LIGHT CURVES OF HOT JUPITERS WITH PHOENIX; A FIRST APPROACH
Directory of Open Access Journals (Sweden)
Juan J. Jiménez-Torres
2016-01-01
Full Text Available A detailed global circulation model was used to feed the PHOENIX code and calculate 3D spectra and light curves of hot Jupiters. Cloud free and dusty radiative fluxes for the planet HD179949b were modeled to show differences between them. The PHOENIX simulations can explain the broad features of the observed 8 µm light curves, including the fact that the planet-star flux ratio peaks before the secondary eclipse. The PHOENIX reflection spectrum matches the Spitzer secondary-eclipse depth at 3.6 µm and underpredicts eclipse depths at 4.5, 5.8 and 8.0 µm. These discrepancies result from the chemical composition and suggest the incorporation of different metallicities in future studies.
3D Modeling of Spectra and Light Curves of Hot Jupiters; A First Approach
Jiménez-Torres, Juan J
2015-01-01
In this paper, a detailed Global Circulation Model was employed to feed the PHOENIX code to calculate 3D spectra and light curves of hot Jupiters. Cloud free and dusty radiative luxes for the planet HD179949b were modeled to show differences between them. The PHOENIX simulations can explain the broad features of the observed 8 {\\mu}m light curves, including the fact that the planet-star flux ratio peaks before the secondary eclipse. The PHOENIX reflection spectrum matches the Spitzer secondary-eclipse depth at 3.6 {\\mu}m and underpredicts the eclipse depths at 4.5, 5.8 and 8.0 {\\mu}m. These discrepancies result from the chemical composition and provide motivation for incorporating different metallicities in future studies.
Assessing change with the extended logistic model.
Cristante, Francesca; Robusto, Egidio
2007-11-01
The purpose of this article is to define a method for the assessment of change. A reinterpretation of the extended logistic model is proposed. The extended logistic model for the assessment of change (ELMAC) allows the definition of a time parameter which is supposed to identify whether change occurs during a period of time, given a specific event or phenomenon. The assessment of a trend of change through time, on the basis of the time parameter which is estimated at different successive occasions during a period of time, is also considered. In addition, a dispersion parameter is calculated which identifies whether change is consistent at each time point. The issue of independence is taken into account both in relation to the time parameter and the dispersion parameter. An application of the ELMAC in a learning process is presented. The interpretation of the model parameters and the model fit statistics is consistent with expectations.
Bayesian Evolution Models for Jupiter with Helium Rain and Double-diffusive Convection
Mankovich, Christopher; Fortney, Jonathan J.; Moore, Kevin L.
2016-12-01
Hydrogen and helium demix when sufficiently cool, and this bears on the evolution of all giant planets at large separations at or below roughly a Jupiter mass. We model the thermal evolution of Jupiter, including its evolving helium distribution following results of ab initio simulations for helium immiscibility in metallic hydrogen. After 4 Gyr of homogeneous evolution, differentiation establishes a thin helium gradient below 1 Mbar that dynamically stabilizes the fluid to convection. The region undergoes overstable double-diffusive convection (ODDC), whose weak heat transport maintains a superadiabatic temperature gradient. With a generic parameterization for the ODDC efficiency, the models can reconcile Jupiter’s intrinsix flux, atmospheric helium content, and radius at the age of the solar system if the Lorenzen et al. H-He phase diagram is translated to lower temperatures. We cast the evolutionary models in an MCMC framework to explore tens of thousands of evolutionary sequences, retrieving probability distributions for the total heavy-element mass, the superadiabaticity of the temperature gradient due to ODDC, and the phase diagram perturbation. The adopted SCvH-I equation of state (EOS) favors inefficient ODDC such that a thermal boundary layer is formed, allowing the molecular envelope to cool rapidly while the deeper interior actually heats up over time. If the overall cooling time is modulated with an additional free parameter to imitate the effect of a colder or warmer EOS, the models favor those that are colder than SCvH-I. In this case the superadiabaticity is modest and warming and cooling deep interiors are equally likely.
An Extended Colored Zee-Babu Model
Nomura, Takaaki
2016-01-01
We study the extended colored Zee-Babu model introducing a vector-like quark and singlet scalar. The active neutrino mass matrix and muon anomalous magnetic moment are analyzed, which can be fitted to experimental data satisfying the constraints from flavor changing neutral current. Then we discuss signature of our model via vector-like quark production. In addition, the diphoton excess can be explained with the contribution from vector-like quark
An empirical model of the high-energy electron environment at Jupiter
Soria-Santacruz, M.; Garrett, H. B.; Evans, R. W.; Jun, I.; Kim, W.; Paranicas, C.; Drozdov, A.
2016-10-01
We present an empirical model of the energetic electron environment in Jupiter's magnetosphere that we have named the Galileo Interim Radiation Electron Model version-2 (GIRE2) since it is based on Galileo data from the Energetic Particle Detector (EPD). Inside 8RJ, GIRE2 adopts the previously existing model of Divine and Garrett because this region was well sampled by the Pioneer and Voyager spacecraft but poorly covered by Galileo. Outside of 8RJ, the model is based on 10 min averages of Galileo EPD data as well as on measurements from the Geiger Tube Telescope on board the Pioneer spacecraft. In the inner magnetosphere the field configuration is dipolar, while in the outer magnetosphere it presents a disk-like structure. The gradual transition between these two behaviors is centered at about 17RJ. GIRE2 distinguishes between the two different regions characterized by these two magnetic field topologies. Specifically, GIRE2 consists of an inner trapped omnidirectional model between 8 to 17RJ that smoothly joins onto the original Divine and Garrett model inside 8RJ and onto a GIRE2 plasma sheet model at large radial distances. The model provides a complete picture of the high-energy electron environment in the Jovian magnetosphere from ˜1 to 50RJ. The present manuscript describes in great detail the data sets, formulation, and fittings used in the model and provides a discussion of the predicted high-energy electron fluxes as a function of energy and radial distance from the planet.
Extended Higgs sectors in radiative neutrino models
Directory of Open Access Journals (Sweden)
Oleg Antipin
2017-05-01
Full Text Available Testable Higgs partners may be sought within the extensions of the SM Higgs sector aimed at generating neutrino masses at the loop level. We study a viability of extended Higgs sectors for two selected models of radiative neutrino masses: a one-loop mass model, providing the Higgs partner within a real triplet scalar representation, and a three-loop mass model, providing it within its two-Higgs-doublet sector. The Higgs sector in the one-loop model may remain stable and perturbative up to the Planck scale, whereas the three-loop model calls for a UV completion around 106 GeV. Additional vector-like lepton and exotic scalar fields, which are required to close one- and three-loop neutrino-mass diagrams, play a decisive role for the testability of the respective models. We constrain the parameter space of these models using LHC bounds on diboson resonances.
Amundsen, David. S.; Tremblin, Pascal; Manners, James; Baraffe, Isabelle; Mayne, Nathan J.
2016-01-01
The correlated-k method is frequently used to speed up radiation calculations in both one-dimensional and three-dimensional atmosphere models. An inherent difficulty with this method is how to treat overlapping absorption, i.e. absorption by more than one gas in a given spectral region. We have evaluated the applicability of three different methods in hot Jupiter and brown dwarf atmosphere models, all of which have been previously applied within models in the literature: (i) Random overlap, b...
Neutrino Anomalies in an Extended Zee Model
Joshipura, A S; Joshipura, Anjan S.; Rindani, Saurabh D.
1999-01-01
We discuss an extended SU(2)X U(1) model which naturally leads to mass scales and mixing angles relevant for understanding both the solar and atmospheric neutrino anomalies. No right-handed neutrinos are introduced in the model.The model uses a softly broken L_e-L_{\\mu}-L_{\\tau} symmetry. Neutrino masses arise only at the loop level. The one-loop neutrino masses which arise as in the Zee model solve the atmospheric neutrino anomaly while breaking of L_e-L_{\\mu}-L_{\\tau} generates at two-loop order a mass splitting needed for the vacuum solution of the solar neutrino problem. A somewhat different model is possible which accommodates the large-angle MSW resolution of the solar neutrino problem.
Understanding Jupiter's Interior
Militzer, Burkhard; Wahl, Sean M; Hubbard, William
2016-01-01
This article provides an overview of how models of giant planet interiors are constructed. We review measurements from past space missions that provide constraints for the interior structure of Jupiter. We discuss typical three-layer interior models that consist of a dense central core and an inner metallic and an outer molecular hydrogen-helium layer. These models rely heavily on experiments, analytical theory, and first-principle computer simulations of hydrogen and helium to understand their behavior up to the extreme pressures ~10 Mbar and temperatures ~10,000 K. We review the various equations of state used in Jupiter models and compare them with shock wave experiments. We discuss the possibility of helium rain, core erosion and double diffusive convection may have important consequences for the structure and evolution of giant planets. In July 2016 the Juno spacecraft entered orbit around Jupiter, promising high-precision measurements of the gravitational field that will allow us to test our understandi...
Action principles for extended magnetohydrodynamic models
Energy Technology Data Exchange (ETDEWEB)
Keramidas Charidakos, I.; Lingam, M.; Morrison, P. J.; White, R. L. [Institute for Fusion Studies and Department of Physics, The University of Texas at Austin, Austin, Texas 78712 (United States); Wurm, A. [Department of Physical and Biological Sciences, Western New England University, Springfield, Massachusetts 01119 (United States)
2014-09-15
The general, non-dissipative, two-fluid model in plasma physics is Hamiltonian, but this property is sometimes lost or obscured in the process of deriving simplified (or reduced) two-fluid or one-fluid models from the two-fluid equations of motion. To ensure that the reduced models are Hamiltonian, we start with the general two-fluid action functional, and make all the approximations, changes of variables, and expansions directly within the action context. The resulting equations are then mapped to the Eulerian fluid variables using a novel nonlocal Lagrange-Euler map. Using this method, we recover Lüst's general two-fluid model, extended magnetohydrodynamic (MHD), Hall MHD, and electron MHD from a unified framework. The variational formulation allows us to use Noether's theorem to derive conserved quantities for each symmetry of the action.
A pseudo 2D chemical model of hot Jupiter atmospheres: application to HD 209458b and HD 189733b
Agundez, Marcelino; Venot, Olivia; Hersant, Franck; Selsis, Franck
2014-01-01
We have developed a pseudo two-dimensional model of a planetary atmosphere, which takes into account thermochemical kinetics, photochemistry, vertical mixing, and horizontal transport, the latter being modeled as a uniform zonal wind. We have applied the model to the atmospheres of the hot Jupiters HD 209458b and HD 189733b. The adopted eddy diffusion coefficients are calculated by following the behaviour of passive tracers in three-dimensional general circulation models, which results in eddy values significantly below previous estimates. We find that the distribution of molecules with altitude and longitude in the atmospheres of these two hot Jupiters is complex because of the interplay of the various physical and chemical processes at work. Much of the distribution of molecules is driven by the strong zonal wind and the limited extent of vertical transport, resulting in an important homogenisation of the chemical composition with longitude. In general, molecular abundances are quenched horizontally to valu...
DEFF Research Database (Denmark)
Nordestgaard, Børge; Ridker, Paul M; MacFadyen, Jean G;
2009-01-01
were calculated across a range of end points, timeframes, and subgroups using data from Justification for the Use of statins in Prevention: an Intervention Trial Evaluating Rosuvastatin (JUPITER), a randomized evaluation of rosuvastatin 20 mg versus placebo conducted among 17 802 apparently healthy men...... infarction, stroke, revascularization, or death, the 5-year NNT within JUPITER was 20 (95% CI, 14 to 34). All subgroups had 5-year NNT values for this end point below 50; as examples, 5-year NNT values were 17 for men and 31 for women, 21 for whites and 19 for nonwhites, 18 for those with body mass index 300...
Heimpel, M. H.; Wicht, J.; Gastine, T.
2015-12-01
Planetary jet streams and vortices have been studied for over 350 years, yet their origin and dynamics are still vigorously debated. On both Jupiter and Saturn zonal flow consists of equatorial superrotation and alternating East-West jets at higher latitude. On Jupiter, numerous vortices, the vast majority anticyclones, occur with various sizes and lifetimes, interacting strongly with the zonal flow. Saturn's vortices and jets are also clearly coupled, and its North and South polar vortices are cyclonic. Models of giant planet atmospheres have generally been of two classes. Shallow flow models produce jets and vortices from 2D turbulence in a very thin spherical layer, but require special conditions to reproduce observed equatorial superrotation. In contrast, deep convection models generically reproduce equatorial superrotation, but typically lack coherent vortices, which do not survive the formation of jets. Here, we combine elements of both approaches using a 3D spherical shell compressible fluid numerical model, driven by convection at depth, but grading to a stably stratified shallow layer. In typical model simulations convective plumes rising from the deep interior impinge on the stably stratified layer, diverge near the outer spherical surface, and efficiently create the dominant anticyclones, which are shielded by downwelling cyclonic rings and filaments. These results may explain the dominance of anticyclones and the flow structure of small and medium sized anticyclonic ovals on Jupiter. The largest of our model vortices form in westward anticyclonic shear nearest the equatorial jet, similar to Saturn's "storm alley" and Jupiter's Great Red Spot. We also explore conditions under which cyclones, including polar cyclones like those on Saturn, may form.
Differential Poisson Sigma Models with Extended Supersymmetry
Arias, Cesar; Torres-Gomez, Alexander
2016-01-01
The induced two-dimensional topological N=1 supersymmetric sigma model on a differential Poisson manifold M presented in arXiv:1503.05625 is shown to be a special case of the induced Poisson sigma model on the bi-graded supermanifold T[0,1]M. The bi-degree comprises the standard N-valued target space degree, corresponding to the form degree on the worldsheet, and an additional Z-valued fermion number, corresponding to the degree in the differential graded algebra of forms on M. The N=1 supersymmetry stems from the compatibility between the (extended) differential Poisson bracket and the de Rham differential on M. The latter is mapped to a nilpotent vector field Q of bi-degree (0,1) on T*[1,0](T[0,1]M), and the covariant Hamiltonian action is Q-exact. New extended supersymmetries arise as inner derivatives along special bosonic Killing vectors on M that induce Killing supervector fields of bi-degree (0,-1) on T*[1,0](T[0,1]M).
Colors and Properties of Jupiter's Greeks and Trojans
Chatelain, Joseph; Henry, Todd J.; French, Linda M.; Trilling, David E.
2016-10-01
In this Ph.D. talk, I will present the colors and properties of Jupiter Trojan asteroids examined in my dissertation research. The Jupiter Trojan asteroids are minor bodies that orbit 60 degrees in front and 60 degrees behind Jupiter. Because these orbits are stable over the lifetime of the Solar System, the properties of these objects may inform us about the conditions under which the Solar System formed. We present BVRKCIKC photometry for over 100 of the intrinsically brightest and presumably largest members of the L4 and L5 Jupiter Trojans. We use a new principal color component derived by Chatelain et al. 2016 that is indicative of taxonomic types relevant to the Jupiter Trojan asteroids. We previously found that 76% of the largest L5 Jupiter Trojans are consistent with a D-type classification, while 24% show shallower slopes more consistent with X-type and C-type classifications. Here we extend this study to the L4 cloud and compare the two populations, as well as include findings about specific objects that have resulted from these data. Specifically, multiple photometric observations hint at color variation in some objects, and our richest datasets allow for the determination of phase curves and shapes for a handful of the most compelling asteroids including a new shape model and pole solution for 1173 Anchises. Our goal is to use this study to shed light on these fascinating objects and to place the Trojans in context in the larger Solar System.
Jupiter's Dynamic Magnetosphere
Vogt, M. F.; Bunce, E. J.; Kronberg, E. A.; Jackman, C. M.
2014-12-01
Jupiter's magnetosphere is a highly dynamic environment. Hundreds of reconnection events have been identified in Jupiter's magnetotail through analysis of magnetic field and particle measurements collected by the Galileo spacecraft. Quasi-periodic behavior, suggestive of reconnection, has been intermittently observed on a ~2-3 day time scale in several data sets, including magnetic field dipolarizations, flow bursts, auroral polar dawn spots, and the hectometric radio emission. In this paper we review the present state of knowledge of Jovian magnetospheric dynamics. Throughout the discussion, we highlight similarities and differences to Saturn's magnetosphere. For example, recent analysis of plasmoid signatures at both Jupiter and Saturn has established the role of tail reconnection in the overall mass and flux transport in the outer planet magnetospheres. The results for both Jupiter and Saturn suggest that the observed mass loss rate due to tail reconnection and plasmoid release is insufficient to account for the mass input rate from the moons Io and Enceladus, respectively. We also present new analysis in which we use the Michigan mSWiM propagated solar wind MHD model to estimate the solar wind conditions upstream of Jupiter. This information allows us to determine whether reconnection events occur preferentially during certain solar wind conditions, or whether there is evidence that the solar wind modulates the quasi-periodicity seen in the field dipolarizations and flow bursts.
Kataria, Tiffany; Fortney, Jonathan J; Stevenson, Kevin B; Line, Michael R; Kreidberg, Laura; Bean, Jacob L; Désert, Jean-Michel
2014-01-01
The hot Jupiter WASP-43b has now joined the ranks of transiting hot Jupiters HD 189733b and HD 209458b as an exoplanet with a large array of observational constraints on its atmospheric properties. Because WASP-43b receives a similar stellar flux as HD 209458b but has a rotation rate 4 times faster and a much higher gravity, studying WASP-43b serves as a test of the effect of rotation rate and gravity on the circulation when stellar irradiation is held approximately constant. Here we present 3D atmospheric circulation models of WASP-43b using the SPARC/MITgcm, a coupled radiation and circulation model, exploring the effects of composition, metallicity, and frictional drag. We find that the circulation regime of WASP-43b is not unlike other hot Jupiters, with equatorial superrotation that yields an eastward-shifted hotspot and large day-night temperature variations (~600 K at photospheric pressures). We then compare our model results to observations from Stevenson et al. which utilize HST/WFC3 to collect spect...
A model for the common origin of Jupiter family and Halley type comets
Emel'yanenko, V V; Bailey, M E
2014-01-01
A numerical simulation of the Oort cloud is used to explain the observed orbital distributions and numbers of Jupiter-family and Halley-type short-period comets. Comets are given initial orbits with perihelion distances between 5 and 36 AU, and evolve under planetary, stellar and Galactic perturbations for 4.5 Gyr. This process leads to the formation of an Oort cloud (which we define as the region of semimajor axes a>1000 AU), and to a flux of cometary bodies from the Oort cloud returning to the planetary region at the present epoch. The results are consistent with the dynamical characteristics of short-period comets and other observed cometary populations: the near-parabolic flux, Centaurs, and high-eccentricity trans-Neptunian objects. To achieve this consistency with observations, the model requires that the number of comets versus initial perihelion distance is concentrated towards the outer planetary region. Moreover, the mean physical lifetime of observable comets in the inner planetary region (q<2.5...
Extending a context model for microphone forensics
Kraetzer, Christian; Qian, Kun; Dittmann, Jana
2012-03-01
In this paper, we extend an existing context model for statistical pattern recognition based microphone forensics by: first, generating a generalized model for this process and second, using this general model to construct a complex new application scenario model for microphone forensic investigations on the detection of playback recordings (a.k.a. replays, re-recordings, double-recordings). Thereby, we build the theoretical basis for answering the question whether an audio recording was made to record a playback or natural sound. The results of our investigations on the research question of playback detection imply that it is possible with our approach on our evaluation set of six microphones. If the recorded sound is not modified prior to playback, we achieve in our tests 89.00% positive indications on the correct two microphones involved. If the sound is post-processed (here, by normalization) this figure decreases (in our normalization example to 36.00%, while another 50.67% of the tests still indicate two microphones, of which one has actually not been involved in the recording and playback recording process).
Nunez, Luis Ernesto; Johnson, John A.
2017-01-01
Hot Jupiters are Jupiter-sized gas giant exoplanets that closely orbit their host star in periods of about 10 days or less. Early models hypothesized that these exoplanets formed away from the star, then over time drifted to their characteristically closer locations. However, new theories predict that Hot Jupiters form at their close proximity during the process of core accretion (Batygin et al. 2015). In fact, a super-Earth and a Neptune-sized exoplanet have already been detected in the Hot Jupiter-hosting star WASP-47 (Becker et al. 2015). We will present our analysis of radial velocity time series plots to determine whether low-mass, short-period planets have been previously overlooked in systems of stars which host Hot Jupiters.The SAO REU program is funded in part by the National Science Foundation REU and Department of Defense ASSURE programs under NSF Grant no. 1262851.
Stansberry, K G; White, R S
1973-12-07
Predictions of Jupiter's electron and proton radiation belts are based mainly on decimeter observations of 1966 and 1968. Extensive calculations modeling radial diffusion of particles inward from the solar wind and electron synchrotron radiation are used to relate the predictions and observations.
Center for Extended Magnetohydrodynamic Modeling Cooperative Agreement
Energy Technology Data Exchange (ETDEWEB)
Carl R. Sovinec
2008-02-15
The Center for Extended Magnetohydrodynamic Modeling (CEMM) is developing computer simulation models for predicting the behavior of magnetically confined plasmas. Over the first phase of support from the Department of Energy’s Scientific Discovery through Advanced Computing (SciDAC) initiative, the focus has been on macroscopic dynamics that alter the confinement properties of magnetic field configurations. The ultimate objective is to provide computational capabilities to predict plasma behavior—not unlike computational weather prediction—to optimize performance and to increase the reliability of magnetic confinement for fusion energy. Numerical modeling aids theoretical research by solving complicated mathematical models of plasma behavior including strong nonlinear effects and the influences of geometrical shaping of actual experiments. The numerical modeling itself remains an area of active research, due to challenges associated with simulating multiple temporal and spatial scales. The research summarized in this report spans computational and physical topics associated with state of the art simulation of magnetized plasmas. The tasks performed for this grant are categorized according to whether they are primarily computational, algorithmic, or application-oriented in nature. All involve the development and use of the Non-Ideal Magnetohydrodynamics with Rotation, Open Discussion (NIMROD) code, which is described at http://nimrodteam.org. With respect to computation, we have tested and refined methods for solving the large algebraic systems of equations that result from our numerical approximations of the physical model. Collaboration with the Terascale Optimal PDE Solvers (TOPS) SciDAC center led us to the SuperLU_DIST software library [http://crd.lbl.gov/~xiaoye/SuperLU/] for solving large sparse matrices using direct methods on parallel computers. Switching to this solver library boosted NIMROD’s performance by a factor of five in typical large
Energy Technology Data Exchange (ETDEWEB)
Kataria, Tiffany; Showman, Adam P. [Department of Planetary Sciences and Lunar and Planetary Laboratory, The University of Arizona, Tucson, AZ 85721 (United States); Fortney, Jonathan J.; Line, Michael R. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Stevenson, Kevin B.; Kreidberg, Laura; Bean, Jacob L. [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States); Désert, Jean-Michel, E-mail: tkataria@astro.ex.ac.uk [CASA, Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309 (United States)
2015-03-10
The hot Jupiter WASP-43b (2 M{sub J}, 1 R{sub J}, T {sub orb} = 19.5 hr) has now joined the ranks of transiting hot Jupiters HD 189733b and HD 209458b as an exoplanet with a large array of observational constraints. Because WASP-43b receives a similar stellar flux as HD 209458b but has a rotation rate four times faster and a higher gravity, studying WASP-43b probes the effect of rotation rate and gravity on the circulation when stellar irradiation is held approximately constant. Here we present three-dimensional (3D) atmospheric circulation models of WASP-43b, exploring the effects of composition, metallicity, and frictional drag. We find that the circulation regime of WASP-43b is not unlike other hot Jupiters, with equatorial superrotation that yields an eastward-shifted hotspot and large day-night temperature variations (∼600 K at photospheric pressures). We then compare our model results to Hubble Space Telescope (HST)/WFC3 spectrophotometric phase curve measurements of WASP-43b from 1.12 to 1.65 μm. Our results show the 5× solar model light curve provides a good match to the data, with a peak flux phase offset and planet/star flux ratio that is similar to observations; however, the model nightside appears to be brighter. Nevertheless, our 5× solar model provides an excellent match to the WFC3 dayside emission spectrum. This is a major success, as the result is a natural outcome of the 3D dynamics with no model tuning. These results demonstrate that 3D circulation models can help interpret exoplanet atmospheric observations, even at high resolution, and highlight the potential for future observations with HST, James Webb Space Telescope, and other next-generation telescopes.
Formation of Jets and Equatorial Superrotation on Jupiter
Schneider, Tapio
2008-01-01
The zonal flow in Jupiter's upper troposphere is organized into alternating retrograde and prograde jets, with a prograde (superrotating) jet at the equator. Existing models posit as the driver of the flow either differential radiative heating of the atmosphere or intrinsic heat fluxes emanating from the deep interior; however, they do not reproduce all large-scale features of Jupiter's jets and thermal structure. Here it is shown that the difficulties in accounting for Jupiter's jets and thermal structure resolve if the effects of differential radiative heating and intrinsic heat fluxes are considered together, and if upper-tropospheric dynamics are linked to a magnetohydrodynamic (MHD) drag that acts deep in the atmosphere. Baroclinic eddies generated by differential radiative heating can account for the off-equatorial jets; meridionally propagating equatorial Rossby waves generated by intrinsic convective heat fluxes can account for the equatorial superrotation. The zonal flow extends deeply into the atmos...
Modeling Electrolyte Solutions with the extended universal quasichemical (UNIQUAC) Model
DEFF Research Database (Denmark)
Thomsen, Kaj
2005-01-01
The extended universal quasichemical (UNIQUAC) model is a thermodynamic model for solutions containing electrolytes and non-electrolytes. The model is a gibbs excess function consisting of a Debye-Hückel term and a standard UNIQUAC term. The model only requires binary, ion specific interaction...... parameters. A unique choice of standard states makes the model able to reproduce solid-liquid, vapor-liquid, and liquid-liquid phase equilibria as well as thermal properties of electrolyte solutions using one set of parameters....
Modeling Electrolyte Solutions with the extended universal quasichemical (UNIQUAC) Model
DEFF Research Database (Denmark)
Thomsen, Kaj
2005-01-01
The extended universal quasichemical (UNIQUAC) model is a thermodynamic model for solutions containing electrolytes and non-electrolytes. The model is a gibbs excess function consisting of a Debye-Hückel term and a standard UNIQUAC term. The model only requires binary, ion specific interaction...... parameters. A unique choice of standard states makes the model able to reproduce solid-liquid, vapor-liquid, and liquid-liquid phase equilibria as well as thermal properties of electrolyte solutions using one set of parameters....
Bougher, Stephen; Ridley, Aaron; Majeed, Tariq; Waite, J. Hunter; Gladstone, Randy; Bell, Jared
2016-07-01
The primary objectives for development and validation of a new 3-D non-hydrostatic model of Jupiter's upper atmosphere is to improve our understanding of Jupiter's thermosphere-ionosphere-magnetosphere system and to provide a global context within which to analyze the data retrieved from the new JUNO mission. The new J-GITM model presently incorporates the progress made on the previous Jupiter-TGCM code (i.e. key parameterizations, ion-neutral chemistry, IR cooling) while also employing the non-hydrostatic numerical core of the Earth Global Ionosphere-Thermosphere Model (GITM). The GITM numerical framework has been successfully applied to Earth, Mars, and Titan (see Ridley et al. [2006], Bougher et al. [2015], Bell [2008, 2010]). Moreover, it has been shown to simulate the effects of strong, localized heat sources (such as joule heating and auroral heating) more accurately than strictly hydrostatic GCMs (Deng et al. [2007, 2008]). Thus far, in the J-GITM model development and testing, model capability has been progressively augmented to capture the neutral composition (e.g. H, H2, He major species), 3-component neutral winds, and thermal structure, as well as the ion composition (H3+, H2+, and H+ among others) above 250 km. Presently, J-GITM: (a) provides an interactive calculation for auroral particle precipitation (i.e. heating, ionization), an improvement over the static formulation used previously in the J-TGCM (Bougher et al., 2005; Majeed et al., 2005, 2009, 2015); (b) self-consistently calculates an ionosphere using updated ion-neutral chemistry, ion dynamics, and electron transport; (c) simulates the chemistry that forms key hydrocarbons at the base of the thermosphere, focusing on CH4, C2H2, and C2H6; (d) allows the production of H3+, CH4, C2H2, and C2H6 to modify the global thermal balance of Jupiter through their non-LTE radiative cooling; (e) provides a calculation of H2 vibrational chemistry to regulate H+ densities; and (f) uses the improved
Tensor Models: extending the matrix models structures and methods
Dartois, Stephane
2016-01-01
In this text we review a few structural properties of matrix models that should at least partly generalize to random tensor models. We review some aspects of the loop equations for matrix models and their algebraic counterpart for tensor models. Despite the generic title of this review, we, in particular, invoke the Topological Recursion. We explain its appearance in matrix models. Then we state that a family of tensor models provides a natural example which satisfies a version of the most general form of the topological recursion, named the blobbed topological recursion. We discuss the difficulties of extending the technical solutions existing for matrix models to tensor models. Some proofs are not published yet but will be given in a coming paper, the rest of the results are well known in the literature.
An Extended Enterprise Modeling Approach to Enterprise-based Integration
Institute of Scientific and Technical Information of China (English)
无
2002-01-01
The paradigm of extended enterprise is the core competency focused. An extended enterprise expands its scope from bounding a single enterprise to including additional processes performed by other enterprises. The integration of processes is enterprise based. This paper proposes a recursive enterprises interconnected chain model for the extended enterprise, and presents an enterprise-based integration framework for the extended enterprise. The case study is based on a motorcycle group corporation.
Extending Model Checking to Object Process Validation
Rein, van H.
2002-01-01
Object-oriented techniques allow the gathering and modelling of system requirements in terms of an application area. The expression of data and process models at that level is a great asset in communication with non-technical people in that area, but it does not necessarily lead to consistent models
Multiphase model for transformation induced plasticity. Extended Leblond's model
Weisz-Patrault, Daniel
2017-09-01
Transformation induced plasticity (TRIP) classically refers to plastic strains observed during phase transitions that occur under mechanical loads (that can be lower than the yield stress). A theoretical approach based on homogenization is proposed to deal with multiphase changes and to extend the validity of the well known and widely used model proposed by Leblond (1989). The approach is similar, but several product phases are considered instead of one and several assumptions have been released. Thus, besides the generalization for several phases, one can mention three main improvements in the calculation of the local equivalent plastic strain: the deviatoric part of the phase transformation is taken into account, both parent and product phases are elastic-plastic with linear isotropic hardening and the applied stress is considered. Results show that classical issues of singularities arising in the Leblond's model (corrected by ad hoc numerical functions or thresholding) are solved in this contribution excepted when the applied equivalent stress reaches the yield stress. Indeed, in this situation the parent phase is entirely plastic as soon as the phase transformation begins and the same singularity as in the Leblond's model arises. A physical explanation of the cutoff function is introduced in order to regularize the singularity. Furthermore, experiments extracted from the literature dealing with multiphase transitions and multiaxial loads are compared with the original Leblond's model and the proposed extended version. For the extended version, very good agreement is observed without any fitting procedures (i.e., material parameters are extracted from other dedicated experiments) and for the original version results are more qualitative.
Thomson, Stephen I
2014-01-01
A longstanding mystery about Jupiter has been the straightness and steadiness of its weather-layer jets, quite unlike terrestrial strong jets with their characteristic unsteadiness and long-wavelength meandering. The problem is addressed in two steps. The first is to take seriously the classic Dowling-Ingersoll $1 {-2pt}\\frac{1}{2}$-layer scenario and its supporting observational evidence. The evidence implies the existence of deep, massive, zonally-symmetric zonal jets in the underlying dry-convective layer. There is then the possibility of straight, stable weather-layer jets with the deep jets acting as guide-rails. Stability is possible even with nonmonotonic weather-layer potential-vorticity gradients. The second step is to improve the realism of the small-scale stochastic forcing used to represent Jupiter's moist convection, as far as possible within the $1 {-2pt}\\frac{1}{2}$-layer dynamics. The real, three-dimensional moist convection should be strongest in the belts where the interface to the deep flow...
An Extended SISa Model for Sentiment Contagion
Directory of Open Access Journals (Sweden)
Zhifeng Liu
2014-01-01
Full Text Available One of the main differences between sentiment and infectious diseases is that the former one has two opposite infectious states: positive (optimistic and negative (pessimistic, while the latter one has not. In this paper, based on the SISa model, we consider this issue and propose a new model of sentiment contagion called the SOSa-SPSa model. The results of both numerical and agent-based simulations show that our model could explain the process of sentiment contagion better than that of Hill et al. (2010. Further analysis shows that both the numbers of optimistic and pessimistic individuals will increase with the probability of spontaneity or contagion and decrease with the probability of recovery. Potential applications of this model in financial market have also been discussed.
A Novel Biped Pattern Generator Based on Extended ZMP and Extended Cart-table Model
Directory of Open Access Journals (Sweden)
Guangbin Sun
2015-07-01
Full Text Available This paper focuses on planning patterns for biped walking on complex terrains. Two problems are solved: ZMP (zero moment point cannot be used on uneven terrain, and the conventional cart-table model does not allow vertical CM (centre of mass motion. For the ZMP definition problem, we propose the extended ZMP (EZMP concept as an extension of ZMP to uneven terrains. It can be used to judge dynamic balance on universal terrains. We achieve a deeper insight into the connection and difference between ZMP and EZMP by adding different constraints. For the model problem, we extend the cart-table model by using a dynamic constraint instead of constant height constraint, which results in a mathematically symmetric set of three equations. In this way, the vertical motion is enabled and the resultant equations are still linear. Based on the extended ZMP concept and extended cart-table model, a biped pattern generator using triple preview controllers is constructed and implemented simultaneously to three dimensions. Using the proposed pattern generator, the Atlas robot is simulated. The simulation results show the robot can walk stably on rather complex terrains by accurately tracking extended ZMP.
Galanti, Eli; Kaspi, Yohai
2017-04-01
Observations of the flow on Jupiter exists essentially only for the cloud-level, which is dominated by strong east-west jet-streams. These have been suggested to result from dynamics in a superficial thin weather-layer, or alternatively be a manifestation of deep interior cylindrical flows. However, it is possible that the observed wind is indeed superficial, yet there exists a completely decoupled deep flow. To date, all models linking the wind, via the induced density anomalies, to the gravity field, to be measured by Juno, consider only flow that is a projection of the observed cloud-level wind. Here we explore the possibility of complex wind dynamics that include both the shallow weather-layer wind, and a deep flow that is decoupled from the flow above it. The upper flow is based on the observed cloud-level flow and is set to decay with depth. The deep flow is constructed to produce cylindrical structures with variable width and magnitude, thus allowing for a wide range of possible scenarios for the unknown deep flow. The combined flow is then related to the density anomalies and gravitational moments via a dynamical model. An adjoint inverse model is used for optimizing the parameters controlling the setup of the deep and surface-bound flows, so that these flows can be reconstructed given a gravity field. We show that the model can be used for examination of various scenarios, including cases in which the deep flow is dominating over the surface wind, and discuss the uncertainties associated with the model solution. The flexibility of the adjoint method allows for a wide range of dynamical setups, so that when new observations and physical understanding will arise, these constraints could be easily implemented and used to better decipher Jupiter flow dynamics.
Ingersoll, A. P.
1976-01-01
From the point of view of meteorology the most important differences between Jupiter and the earth are related to the fact that Jupiter has an appreciable internal energy source and probably lacks a solid surface. The composition and vertical structure of the Jovian atmosphere is considered along with the composition of Jovian cloud particles, turbulence in Jupiter's atmosphere, data on the horizontal structure and motions of the atmosphere, and questions related to the longevity of Jupiter's clouds. Attention is given to the barotropic characteristics of Jupiter's atmosphere, the radiation balance in the atmosphere of the earth and of Jupiter, and studies of the Great Red Spot.
Amundsen, David S.; Mayne, Nathan J.; Baraffe, Isabelle; Manners, James; Tremblin, Pascal; Drummond, Benjamin; Smith, Chris; Acreman, David M.; Homeier, Derek
2016-10-01
To study the complexity of hot Jupiter atmospheres revealed by observations of increasing quality, we have adapted the UK Met Office Global Circulation Model (GCM), the Unified Model (UM), to these exoplanets. The UM solves the full 3D Navier-Stokes equations with a height-varying gravity, avoiding the simplifications used in most GCMs currently applied to exoplanets. In this work we present the coupling of the UM dynamical core to an accurate radiation scheme based on the two-stream approximation and correlated-k method with state-of-the-art opacities from ExoMol. Our first application of this model is devoted to the extensively studied hot Jupiter HD 209458b. We have derived synthetic emission spectra and phase curves, and compare them to both previous models also based on state-of-the-art radiative transfer, and to observations. We find a reasonable agreement between observations and both our days side emission and hot spot offset, however, our night side emissions is too large. Overall our results are qualitatively similar to those found by Showman et al. (2009, ApJ, 699, 564) with the SPARC/MITgcm, however, we note several quantitative differences: Our simulations show significant variation in the position of the hottest part of the atmosphere with pressure, as expected from simple timescale arguments, and in contrast to the "vertical coherency" found by Showman et al. (2009). We also see significant quantitative differences in calculated synthetic observations. Our comparisons strengthen the need for detailed intercomparisons of dynamical cores, radiation schemes and post-processing tools to understand these differences. This effort is necessary in order to make robust conclusions about these atmospheres based on GCM results.
Extended Linear Models with Gaussian Priors
DEFF Research Database (Denmark)
Quinonero, Joaquin
2002-01-01
on the parameters. The Relevance Vector Machine, introduced by Tipping, is a particular case of such a model. I give the detailed derivations of the expectation-maximisation (EM) algorithm used in the training. These derivations are not found in the literature, and might be helpful for newcomers....
Extending Social Cognition Models of Health Behaviour
Abraham, Charles; Sheeran, Paschal; Henderson, Marion
2011-01-01
A cross-sectional study assessed the extent to which indices of social structure, including family socio-economic status (SES), social deprivation, gender and educational/lifestyle aspirations correlated with adolescent condom use and added to the predictive utility of a theory of planned behaviour model. Analyses of survey data from 824 sexually…
Extending Social Cognition Models of Health Behaviour
Abraham, Charles; Sheeran, Paschal; Henderson, Marion
2011-01-01
A cross-sectional study assessed the extent to which indices of social structure, including family socio-economic status (SES), social deprivation, gender and educational/lifestyle aspirations correlated with adolescent condom use and added to the predictive utility of a theory of planned behaviour model. Analyses of survey data from 824 sexually…
Extended Weyl Invariance in a Bimetric Model
Hassan, S F; von Strauss, Mikael
2015-01-01
We revisit a particular ghost-free bimetric model which is related to both partial masslessness as well conformal gravity. Its equations of motion can be recast in the form of a perturbative series in derivatives which exhibits a remarkable amount of structure. In a perturbative (but fully nonlinear) analysis, we demonstrate that the equations are invariant under scalar gauge transformations up to six orders in derivatives, the lowest-order term being a local Weyl scaling of the metrics. More specifically, we develop a procedure for constructing terms in the gauge transformations order by order in the perturbative framework. This allows us to derive sufficient conditions for the existence of a gauge symmetry at the nonlinear level. It is explicitly demonstrated that these conditions are satisfied at the first relevant order and, consequently, the equations are gauge invariant up to six orders in derivatives. We furthermore show that the model propagates six instead of seven degrees of freedom not only around ...
Extending and Refining the Propaganda Model
Sparks, Colin
2007-01-01
The ‘propaganda model’ of news production in capitalist democracies elaborated by Edward S. Herman and Noam Chomsky in 1988 was met with initial hostile criticism and then more or less complete neglect. In the last five years, there has been a renewal of interest, although opinion remains seriously divided. This article adopts a sympathetic stance towards the main ideas of the model, but suggests that there are a number of ways in which in its classical iteration it is insufficiently sensitiv...
Macroeconomic model of national economy development (extended
Directory of Open Access Journals (Sweden)
M. Diaconova
1997-08-01
Full Text Available The macroeconomic model offered in this paper describes complex functioning of national economy and can be used for forecasting of possible directions of its development depending on various economic policies. It is the extension of [2] and adaptation of [3]. With the purpose of determination of state policies influence in the field of taxes and exchange rate national economy is considered within the framework of three sectors: government, private and external world.
Extending Ansoff’s Strategic Diagnosis Model
Directory of Open Access Journals (Sweden)
Daniel Kipley
2012-01-01
Full Text Available Given the complex and disruptive open-ended dynamics in the current dynamic global environment, senior management recognizes the need for a formalized, consistent, and comprehensive framework to analyze the firm’s strategic posture. Modern assessment tools, such as H. Igor Ansoff’s seminal contributions to strategic diagnosis, primarily focused on identifying and enhancing the firm’s strategic performance potential through the analysis of the industry’s environmental turbulence level relative to the firm’s aggressiveness and responsiveness of capability. Other epistemic modeling techniques envisage Porter’s generic strategic positions, Strengths, Weaknesses, Opportunities, Threats (SWOT, and Resource-Based View as useful methodologies to aid in the planning process. All are complex and involve multiple managerial perspectives. Over the last two decades, attempts have been made to comprehensively classify the firm’s future competitive position. Most of these proposals utilized matrices to depict the position, such as the Boston Consulting Group, point positioning, and dispersed positioning. The GE/McKinsey later enhanced this typology by expanding to 3 × 3, contributing to management’s deeper understanding of the firm’s position. Both types of assessments, Ansoff’s strategic diagnosis and positional matrices, are invaluable strategic tools for firms. However, it could be argued that these positional analyses singularly reflect a blind spot in modeling the firm’s future strategic performance potential, as neither considers the interactions of the other. This article is conceptual and takes a different approach from earlier methodologies. Although conceptual, the article aims to present a robust model combining Ansoff’s strategic diagnosis with elements of the performance matrices to provide the management with an enriched capability to evaluate the firm’s current and future performance position.
An Examination of Extended a-Rescaling Model
Institute of Scientific and Technical Information of China (English)
YAN Zhan-Yuan; DUAN Chun-Gui; HE Zhen-Min
2001-01-01
The extended x-rescaling model can explain the quark's nuclear effect very well. Weather it can also explain the gluon's nuclear effect should be investigated further. Associated J/ψ and γ production with large PT is a very clean channel to probe the gluon distribution in proton or nucleus. In this paper, using the extended x-rescaling model, the PT distribution of the nuclear effect factors of p + Fe → J/Ψ + γ+ X process is calculated and discussed. Comparing our theoretical results with the future experimental data, the extended x-rescaling model can be examined.``
Extending the prevalent consumer loyalty modelling
DEFF Research Database (Denmark)
Olsen, Svein Ottar; Tudoran, Ana Alina; Brunsø, Karen
2013-01-01
Purpose: This study addresses the role of habit strength in explaining loyalty behaviour. Design/methodology/approach: The study uses 2063 consumers’ data from a survey in Denmark and Spain, and multigroup structural equation modelling to analyse the data. The paper describes an approach employing...... the psychological meanings of the habit construct, such as automaticity, lack of awareness or very little conscious deliberation. Findings: The findings suggest that when habits start to develop and gain strength, less planning is involved, and that the loyalty behaviour sequence mainly occurs guided...... literature by providing an extension of the prevalent consumer loyalty theorizing by integrating the concept of habit strength and by generating new knowledge concerning the conscious/strategic and unconscious/automatic nature of consumer loyalty. The study derives managerial implications on how...
Extended Quark Potential Model From Random Phase Approximation
Institute of Scientific and Technical Information of China (English)
DENGWei－Zhen; CHENXiao－Lin; 等
2002-01-01
The quark potential model is extended to include the sea quark excitation using the random phase approximation.The effective quark interaction preserves the important QCD properties-chiral symmetry and confinement simultaneously.A primary qualitative analysis shows that the π meson as a well-known typical Goldstone boson and the other mesons made up of valence qq quark pair such as the ρ meson can also be described in this extended quark potential model.
Extended Quark Potential Model from Random Phase Approximation
Institute of Scientific and Technical Information of China (English)
DENG Wei-Zhen; CHEN Xiao-Lin; LU Da-Hai; YANG Li-Ming
2002-01-01
The quark potential model is extended to include the sea quark excitation using the random phase approx-imation. The effective quark interaction preserves the important QCD properties - chiral symmetry and confinementsimultaneously. A primary qualitative analysis shows that the π meson as a well-known typical Goldstone boson andthe other mesons made up of valence qq quark pair such as the ρ meson can also be described in this extended quarkpotential model.
Extended Goldstone-boson-exchange constituent quark model
Wagenbrunn, R F; Plessas, W; Varga, K
2000-01-01
We discuss an updated version of the Goldstone-boson-exchange chiral quark model extended to include in addition to pseudoscalar meson exchanges also vector and scalar meson exchanges. The latter ingredients are viewed as effective parametrizations of multiple Goldstone-boson exchanges in baryons. The extended model allows for an accurate description of all light and strange baryon spectra and at the same time produces the right properties for deducing baryon-baryon interactions.
Nénon, Quentin; Sicard-Piet, Angélica
2017-04-01
From 1998 to 2004, ONERA has adapted its 3D physical model of the Earth radiation belts, Salammbô, to the Jovian electron belts. An upgraded Jupiter-Salammbô model will be presented, now taking into account the gyro-resonant interaction with the plasma waves between Io and Europa. The full spectrum of the electromagnetic waves detected by the Galileo Plasma Wave Science experiment was considered. The WAPI (WAve-Particle Interaction) code, developed by ONERA and implementing the quasi-linear theory, has then been used to estimate the pitch angle and kinetic energy diffusion rates. Regarding the boundary condition, the Galileo Energetic Particle Detector (EPD) high-resolution data suggests that the electron distribution at a Mc Illwain parameter of L=9.5 is almost isotropic, with a flux ratio between equatorial electrons and those bouncing near the loss cone lower than 5 at all the observed kinetic energies. We therefore adopted an isotropic boundary condition at L=9.5 that relies on the in-situ flux measurements coming from the Pioneer 10, Pioneer 11, Voyager 1 and Galileo missions. We propose to model the radial diffusion process with a diffusion coefficient DLL = 10-10L4s-1 for L extending from 1 to 9.5. The validation of the new model against in-situ and remote (synchrotron emission) observations will be presented. We will then discuss the effect of the wave-particle interaction on the predicted in-situ fluxes. In particular, the observable depletions of the Pioneer and Voyager fluxes near the orbit of Io seem to be predominantly induced by the plasma waves and not by the sweeping effect of Io.
Energy Technology Data Exchange (ETDEWEB)
Pierens, Arnaud; Raymond, Sean N. [Laboratoire d' Astrophysique de Bordeaux, Univ. Bordeaux, UMR 5804, F-33270 Floirac (France); Nesvorny, David [Department of Space Studies, Southwest Research Institute, 1050 Walnut Street Suite 300, Boulder, CO 80302 (United States); Morbidelli, Alessandro, E-mail: arnaud.pierens@obs.u-bordeaux1.fr [University of Nice-Sophia Antipolis, CNRS, Observatoire de la côte d' Azur, Laboratoire Lagrange, BP4229, F-06304 NICE Cedex 4 (France)
2014-11-01
Embedded in the gaseous protoplanetary disk, Jupiter and Saturn naturally become trapped in 3:2 resonance and migrate outward. This serves as the basis of the Grand Tack model. However, previous hydrodynamical simulations were restricted to isothermal disks, with moderate aspect ratio and viscosity. Here we simulate the orbital evolution of the gas giants in disks with viscous heating and radiative cooling. We find that Jupiter and Saturn migrate outward in 3:2 resonance in modest-mass (M {sub disk} ≈ M {sub MMSN}, where MMSN is the {sup m}inimum-mass solar nebula{sup )} disks with viscous stress parameter α between 10{sup –3} and 10{sup –2}. In disks with relatively low-mass (M {sub disk} ≲ M {sub MMSN}), Jupiter and Saturn get captured in 2:1 resonance and can even migrate outward in low-viscosity disks (α ≤ 10{sup –4}). Such disks have a very small aspect ratio (h ∼ 0.02-0.03) that favors outward migration after capture in 2:1 resonance, as confirmed by isothermal runs which resulted in a similar outcome for h ∼ 0.02 and α ≤ 10{sup –4}. We also performed N-body runs of the outer solar system starting from the results of our hydrodynamical simulations and including 2-3 ice giants. After dispersal of the gaseous disk, a Nice model instability starting with Jupiter and Saturn in 2:1 resonance results in good solar systems analogs. We conclude that in a cold solar nebula, the 2:1 resonance between Jupiter and Saturn can lead to outward migration of the system, and this may represent an alternative scenario for the evolution of the solar system.
Amundsen, David S; Manners, James; Baraffe, Isabelle; Mayne, Nathan J
2016-01-01
The correlated-k method is frequently used to speed up radiation calculations in both one-dimensional and three-dimensional atmosphere models. An inherent difficulty with this method is how to treat overlapping absorption, i.e. absorption by more than one gas in a given spectral region. We have evaluated the applicability of three different methods in hot Jupiter and brown dwarf atmosphere models, all of which have been previously applied within models in the literature: (i) Random overlap, both with and without resorting and rebinning, (ii) equivalent extinction and (iii) pre-mixing of opacities, where (i) and (ii) combine k-coefficients for different gases to obtain k-coefficients for a mixture of gases, while (iii) calculates k-coefficients for a given mixture from the corresponding mixed line-by-line opacities. We find that the random overlap method is the most accurate and flexible of these treatments, and is fast enough to be used in one-dimensional models with resorting and rebinning. In three-dimensio...
An extended car-following model at signalized intersections
Yu, Shaowei; Shi, Zhongke
2014-08-01
To simulate car-following behaviors better when the traffic light is red, three successive car-following data at a signalized intersection of Jinan in China were collected by using a new proposed data acquisition method and then analyzed to select input variables of the extended car-following model. An extended car-following model considering two leading cars' accelerations was proposed, calibrated and verified with field data obtained on the basis of the full velocity difference model and then a comparative model used for comparative research was also proposed and calibrated in the light of the GM model. The results indicate that the extended car-following model could fit measured data well, and that the fitting precision of the extended model is prior to the comparative model, whose mean absolute error is reduced by 22.83%. Finally a theoretical car-following model considering multiple leading cars' accelerations was put forward which has potential applicable to vehicle automation system and vehicle safety early warning system, and then the linear stability analysis and numerical simulations were conducted to analyze some observed physical features existing in the realistic traffic.
Decaying Domain Walls in an Extended Gravity Model and Cosmology
Shiraishi, Kiyoshi
2013-01-01
We investigate cosmological consequences of an extended gravity model which belongs to the same class studied by Accetta and Steinhardt in an extended inflationary scenario. But we do not worry about inflation in our model; instead, we focus on a topological object formed during cosmological phase transitions. Although domain walls appear during first-order phase transitions such as QCD transition, they decay at the end of the phase transition. Therefore the "domain wall problem" does not exist in the suitable range of pameters and, on the contrary, the "fragments" of walls may become seeds of dark matter. A possible connection to "oscillating universe" model offered by Morikawa et al. is also discussed.
Phenomenological study of extended seesaw model for light sterile neutrino
Nath, Newton; Goswami, Srubabati; Gupta, Shivani
2016-01-01
We study the zero textures of the Yukawa matrices in the minimal extended type-I seesaw (MES) model which can give rise to $\\sim$ eV scale sterile neutrinos. In this model, three right handed neutrinos and one extra singlet $S$ are added to generate a light sterile neutrino. The light neutrino mass matrix for the active neutrinos, $ m_{\
Extended Hubbard models for ultracold atoms in optical lattices
Energy Technology Data Exchange (ETDEWEB)
Juergensen, Ole
2015-06-05
In this thesis, the phase diagrams and dynamics of various extended Hubbard models for ultracold atoms in optical lattices are studied. Hubbard models are the primary description for many interacting particles in periodic potentials with the paramount example of the electrons in solids. The very same models describe the behavior of ultracold quantum gases trapped in the periodic potentials generated by interfering beams of laser light. These optical lattices provide an unprecedented access to the fundamentals of the many-particle physics that govern the properties of solid-state materials. They can be used to simulate solid-state systems and validate the approximations and simplifications made in theoretical models. This thesis revisits the numerous approximations underlying the standard Hubbard models with special regard to optical lattice experiments. The incorporation of the interaction between particles on adjacent lattice sites leads to extended Hubbard models. Offsite interactions have a strong influence on the phase boundaries and can give rise to novel correlated quantum phases. The extended models are studied with the numerical methods of exact diagonalization and time evolution, a cluster Gutzwiller approximation, as well as with the strong-coupling expansion approach. In total, this thesis demonstrates the high relevance of beyond-Hubbard processes for ultracold atoms in optical lattices. Extended Hubbard models can be employed to tackle unexplained problems of solid-state physics as well as enter previously inaccessible regimes.
Creating a Generic Extended Enterprise Management Model using GERAM
DEFF Research Database (Denmark)
Larsen, Lars Bjørn; Kaas-Pedersen, Carsten; Vesterager, Johan
1998-01-01
The two main themes of the Globeman21 (Global Manufacturing in the 21st century) project are product life cycle management and extended enterprise management. This article focus on the later of these subjects and an illustration of the concept is given together with a discussion of the concept...... management model. By working with GERAM in relation to extended enterprise management it has been found that it provides a useful background for organising knowledge, experience and the activities within the project...... of virtual enterprises. Through the introduction of GERAM (Generalised Enterprise Reference Architecture and Methodology) an initial version of a basic framework for extended enterprise management is introduced. This basic framework is the first step towards the creation of a generic extended enterprise...
Amundsen, David S.; Tremblin, Pascal; Manners, James; Baraffe, Isabelle; Mayne, Nathan J.
2017-02-01
The correlated-k method is frequently used to speed up radiation calculations in both one-dimensional and three-dimensional atmosphere models. An inherent difficulty with this method is how to treat overlapping absorption, i.e. absorption by more than one gas in a given spectral region. We have evaluated the applicability of three different methods in hot Jupiter and brown dwarf atmosphere models, all of which have been previously applied within models in the literature: (i) random overlap, both with and without resorting and rebinning, (ii) equivalent extinction and (iii) pre-mixing of opacities, where (i) and (ii) combine k-coefficients for different gases to obtain k-coefficients for a mixture of gases, while (iii) calculates k-coefficients for a given mixture from the corresponding mixed line-by-line opacities. We find that the random overlap method is the most accurate and flexible of these treatments, and is fast enough to be used in one-dimensional models with resorting and rebinning. In three-dimensional models such as global circulation models (GCMs) it is too slow, however, and equivalent extinction can provide a speed-up of at least a factor of three with only a minor loss of accuracy while at the same time retaining the flexibility gained by combining k-coefficients computed for each gas individually. Pre-mixed opacities are significantly less flexible, and we also find that particular care must be taken when using this method in order to to adequately resolve steep variations in composition at important chemical equilibrium boundaries. We use the random overlap method with resorting and rebinning in our one-dimensional atmosphere model and equivalent extinction in our GCM, which allows us to e.g. consistently treat the feedback of non-equilibrium chemistry on the total opacity and therefore the calculated P-T profiles in our models.
Jupiter internal structure: the effect of different equations of state
Miguel, Yamila; Fayon, Lucile
2016-01-01
Heavy elements, even though its smaller constituent, are crucial to understand Jupiter formation history. Interior models are used to determine the amount of heavy elements in Jupiter interior, nevertheless this range is still subject to degeneracies due to uncertainties in the equations of state. Prior to Juno mission data arrival, we present Jupiter optimized calculations exploring the effect of different model parameters in the determination of Jupiter's core and heavy element's mass. We perform comparisons between equations of state published recently. The interior model of Jupiter is calculated from the equations of hydrostatic equilibrium, mass and energy conservation, and energy transport. The mass of the core and heavy elements is adjusted to match Jupiter's observational constrains radius and gravitational moments. We show that the determination of Jupiter interior structure is tied to the estimation of its gravitational moments and the accuracy of equations of state of hydrogen, helium and heavy ele...
Extending the Relational Model to Deal with Probabilistic Data
Institute of Scientific and Technical Information of China (English)
MA Zongmin; ZHANG W. J; MA W. Y.
2000-01-01
According to the soundness and completeness of information in databases, the expressive form and the semantics of incomplete information are discussed in this paper. On the basis of the discussion, the current studies on incomplete data in relational databases are reviewed. In order to represent stochastic uncertainty in most general sense in the real world, probabilistic data are introduced into relational databases. An extended relational data model is presented to express and manipulate probabilistic data and the operations in relational algebra based on the extended model are defined in this paper.
Extending product modeling methods for integrated product development
DEFF Research Database (Denmark)
Bonev, Martin; Wörösch, Michael; Hauksdóttir, Dagný
2013-01-01
Despite great efforts within the modeling domain, the majority of methods often address the uncommon design situation of an original product development. However, studies illustrate that development tasks are predominantly related to redesigning, improving, and extending already existing products....... Updated design requirements have then to be made explicit and mapped against the existing product architecture. In this paper, existing methods are adapted and extended through linking updated requirements to suitable product models. By combining several established modeling techniques, such as the DSM...... and PVM methods, in a presented Product Requirement Development model some of the individual drawbacks of each method could be overcome. Based on the UML standard, the model enables the representation of complex hierarchical relationships in a generic product model. At the same time it uses matrix...
De Pater, I.
1981-01-01
A comparison has been made between detailed model calculations of Jupiter's synchrotron radiation and the radio data at wavelengths of 6, 21, and 50 cm. The calculations were performed for a Jovian longitude of 200 deg and were based on the multipole field configurations as derived from the Pioneer data. The electron distribution in the inner magnetosphere was derived as a function of energy, pitch angle, and spatial coordinates. In addition, the hot region or east-west asymmetry in the radiation belts is investigated. It is suggested that this asymmetry is due to the combined effect of an overabundance of electrons at jovicentric longitudes of 240-360 deg and the existence of a dusk-to-dawn directed electric field over the inner magnetosphere generated by the wind system in the upper atmosphere.
A Design for Composing and Extending Vehicle Models
Madden, Michael M.; Neuhaus, Jason R.
2003-01-01
The Systems Development Branch (SDB) at NASA Langley Research Center (LaRC) creates simulation software products for research. Each product consists of an aircraft model with experiment extensions. SDB treats its aircraft models as reusable components, upon which experiments can be built. SDB has evolved aircraft model design with the following goals: 1. Avoid polluting the aircraft model with experiment code. 2. Discourage the copy and tailor method of reuse. The current evolution of that architecture accomplishes these goals by reducing experiment creation to extend and compose. The architecture mechanizes the operational concerns of the model's subsystems and encapsulates them in an interface inherited by all subsystems. Generic operational code exercises the subsystems through the shared interface. An experiment is thus defined by the collection of subsystems that it creates ("compose"). Teams can modify the aircraft subsystems for the experiment using inheritance and polymorphism to create variants ("extend").
Extended Range Hydrological Predictions: Uncertainty Associated with Model Parametrization
Joseph, J.; Ghosh, S.; Sahai, A. K.
2016-12-01
The better understanding of various atmospheric processes has led to improved predictions of meteorological conditions at various temporal scale, ranging from short term which cover a period up to 2 days to long term covering a period of more than 10 days. Accurate prediction of hydrological variables can be done using these predicted meteorological conditions, which would be helpful in proper management of water resources. Extended range hydrological simulation includes the prediction of hydrological variables for a period more than 10 days. The main sources of uncertainty in hydrological predictions include the uncertainty in the initial conditions, meteorological forcing and model parametrization. In the present study, the Extended Range Prediction developed for India for monsoon by Indian Institute of Tropical Meteorology (IITM), Pune is used as meteorological forcing for the Variable Infiltration Capacity (VIC) model. Sensitive hydrological parameters, as derived from literature, along with a few vegetation parameters are assumed to be uncertain and 1000 random values are generated given their prescribed ranges. Uncertainty bands are generated by performing Monte-Carlo Simulations (MCS) for the generated sets of parameters and observed meteorological forcings. The basins with minimum human intervention, within the Indian Peninsular region, are identified and validation of results are carried out using the observed gauge discharge. Further, the uncertainty bands are generated for the extended range hydrological predictions by performing MCS for the same set of parameters and extended range meteorological predictions. The results demonstrate the uncertainty associated with the model parametrisation for the extended range hydrological simulations. Keywords: Extended Range Prediction, Variable Infiltration Capacity model, Monte Carlo Simulation.
Senske, Dave; Kwok, Johnny
2008-01-01
This slide presentation reviews the proposed mission for the Jupiter System Observer. The presentation also includes overviews of the mission timeline, science goals, and spacecraftspecifications for the satellite.
Galanti, Eli
2016-01-01
Observations of the flow on Jupiter exists essentially only for the cloud-level, which is dominated by strong east-west jet-streams. These have been suggested to result from dynamics in a superficial thin weather-layer, or alternatively be a manifestation of deep interior cylindrical flows. However, it is possible that the observed winds are indeed superficial, yet there exists deep flow that is completely decoupled from it. To date, all models linking the wind, via the induced density anomalies, to the gravity field, to be measured by Juno, consider only flow that is a projection of the observed could-level wind. Here we explore the possibility of complex wind dynamics that include both the shallow weather-layer wind, and a deep flow that is decoupled from the flow above it. The upper flow is based on the observed cloud-level flow and is set to decay with depth. The deep flow is constructed to produce cylindrical structures with variable width and magnitude, thus allowing for a wide range of possible scenari...
Extended propagation model for interfacial crack in composite material structure
Institute of Scientific and Technical Information of China (English)
闫相桥; 冯希金
2002-01-01
An interfacial crack is a common damage in a composite material structure . An extended propaga-tion model has been established for an interfacial crack to study the dependence of crack growth on the relativesizes of energy release rates at left and right crack tips and the properties of interfacial material characterize thegrowth of interfacial crack better.
Extended FEM modeling of crack paths near inclusions
DEFF Research Database (Denmark)
Nielsen, Chris Valentin; Legarth, Brian Nyvang; Niordson, Christian Frithiof
2012-01-01
The extended FEM is applied to model crack growth near inclusions. A procedure to handle different propagation rates at different crack tips is presented. The examples considered investigate uniform tension as well as equibiaxial tension under plane strain conditions. A parameter study analyzes...
The Extended Parallel Process Model: Illuminating the Gaps in Research
Popova, Lucy
2012-01-01
This article examines constructs, propositions, and assumptions of the extended parallel process model (EPPM). Review of the EPPM literature reveals that its theoretical concepts are thoroughly developed, but the theory lacks consistency in operational definitions of some of its constructs. Out of the 12 propositions of the EPPM, a few have not…
The asteroid belt outer region under jumping-Jupiter migration
Gaspar, H. S.; Winter, O. C.; Vieira Neto, E.
2017-09-01
The radial configuration of the outer region of the main asteroid belt is quite peculiar, and has much to say about the past evolution of Jupiter. In this work, we investigate the dynamical effects of a jumping-Jupiter-like migration over a more extended primordial asteroid belt. Jupiter's migrations are simulated using a fast jumping-Jupiter synthesizer. Among the results, we highlight non-negligible fractions of primordial objects trapped in 3:2 and 4:3 mean motion resonances (MMRs) with Jupiter. They survived the whole truculent phase of migration and originated populations that are like Hildas and Thules. Fractions ranging from 3 to 6 per cent of the initial distribution remained trapped in 3:2 MMR, and at least 0.05 per cent in 4:3. These results show that the resonance trapping of primordial objects may have originated these resonant populations. This theory is consistent even for Jupiter's truculent evolution.
Parameter Estimation of the Extended Vasiček Model
Rujivan, Sanae
2010-01-01
In this paper, an estimate of the drift and diffusion parameters of the extended Vasiček model is presented. The estimate is based on the method of maximum likelihood. We derive a closed-form expansion for the transition (probability) density of the extended Vasiček process and use the expansion to construct an approximate log-likelihood function of a discretely sampled data of the process. Approximate maximum likelihood estimators (AMLEs) of the parameters are obtained by maximizing the appr...
Layered Workflow Process Model Based on Extended Synchronizer
Directory of Open Access Journals (Sweden)
Gang Ni
2014-07-01
Full Text Available The layered workflow process model provide a modeling approach and analysis for the key process with Petri Net. It not only describes the relation between the process of business flow and transition nodes clearly, but also limits the rapid increase in the scale of libraries, transition and directed arcs. This paper studies the process like reservation and complaint handling information management system, especially for the multi-mergence and discriminator patterns which can not be directly modeled with existing synchronizers. Petri Net is adopted to provide formalization description for the workflow patterns and the relation between Arcs and weight class are also analyzed. We use the number of in and out arcs to generalize the workflow into three synchronous modes: fully synchronous mode, competition synchronous mode and asynchronous mode. The types and parameters for synchronization are added to extend the modeling ability of the synchronizers and the synchronous distance is also expanded. The extended synchronizers have the ability to terminate branches automatically or activate the next link many times, besides the ability of original synchronizers. By the analyses on cases of the key business, it is verified that the original synchronizers can not model directly, while the extended synchronizers based on Petri Net can provide modeling for multi-mergence and discriminator modes.
Creating a Generic Extended Enterprise Management Model using GERAM
DEFF Research Database (Denmark)
Larsen, Lars Bjørn; Kaas-Pedersen, Carsten; Vesterager, Johan
1998-01-01
The two main themes of the Globeman21 (Global Manufacturing in the 21st century) project are product life cycle management and extended enterprise management. This article focus on the later of these subjects and an illustration of the concept is given together with a discussion of the concept of...... management model. By working with GERAM in relation to extended enterprise management it has been found that it provides a useful background for organising knowledge, experience and the activities within the project......The two main themes of the Globeman21 (Global Manufacturing in the 21st century) project are product life cycle management and extended enterprise management. This article focus on the later of these subjects and an illustration of the concept is given together with a discussion of the concept...... of virtual enterprises. Through the introduction of GERAM (Generalised Enterprise Reference Architecture and Methodology) an initial version of a basic framework for extended enterprise management is introduced. This basic framework is the first step towards the creation of a generic extended enterprise...
Center for Extended Magnetohydrodynamics Modeling - Final Technical Report
Energy Technology Data Exchange (ETDEWEB)
Parker, Scott [Univ. of Colorado, Boulder, CO (United States)
2016-02-14
This project funding supported approximately 74 percent of a Ph.D. graduate student, not including costs of travel and supplies. We had a highly successful research project including the development of a second-order implicit electromagnetic kinetic ion hybrid model [Cheng 2013, Sturdevant 2016], direct comparisons with the extended MHD NIMROD code and kinetic simulation [Schnack 2013], modeling of slab tearing modes using the fully kinetic ion hybrid model and finally, modeling global tearing modes in cylindrical geometry using gyrokinetic simulation [Chen 2015, Chen 2016]. We developed an electromagnetic second-order implicit kinetic ion fluid electron hybrid model [Cheng 2013]. As a first step, we assumed isothermal electrons, but have included drift-kinetic electrons in similar models [Chen 2011]. We used this simulation to study the nonlinear evolution of the tearing mode in slab geometry, including nonlinear evolution and saturation [Cheng 2013]. Later, we compared this model directly to extended MHD calculations using the NIMROD code [Schnack 2013]. In this study, we investigated the ion-temperature-gradient instability with an extended MHD code for the first time and got reasonable agreement with the kinetic calculation in terms of linear frequency, growth rate and mode structure. We then extended this model to include orbit averaging and sub-cycling of the ions and compared directly to gyrokinetic theory [Sturdevant 2016]. This work was highlighted in an Invited Talk at the International Conference on the Numerical Simulation of Plasmas in 2015. The orbit averaging sub-cycling multi-scale algorithm is amenable to hybrid architectures with GPUS or math co-processors. Additionally, our participation in the Center for Extend Magnetohydrodynamics motivated our research on developing the capability for gyrokinetic simulation to model a global tearing mode. We did this in cylindrical geometry where the results could be benchmarked with existing eigenmode
Morrison, David; Samz, Jane
This publication illustrates the features of Jupiter and its family of satellites pictured by the Pioneer and the Voyager missions. Chapters included are: (1) "The Jovian System" (describing the history of astronomy); (2) "Pioneers to Jupiter" (outlining the Pioneer Mission); (3) "The Voyager Mission"; (4)…
Pierens, Arnaud; Nesvorny, David; Morbidelli, Alessandro
2014-01-01
Embedded in the gaseous protoplanetary disk, Jupiter and Saturn naturally become trapped in 3:2 resonance and migrate outward. This serves as the basis of the Grand Tack model. However, previous hydrodynamical simulations were restricted to isothermal disks, with moderate aspect ratio and viscosity. Here we simulate the orbital evolution of the gas giants in disks with viscous heating and radiative cooling. We find that Jupiter and Saturn migrate outward in 3:2 resonance in modest-mass ($M_{disk} \\approx M_{MMSN}$, where MMSN is the "minimum-mass solar nebula") disks with viscous stress parameter $\\alpha$ between $10^{-3}$ and $10^{-2} $. In disks with relatively low-mass ($M_{disk} \\lesssim M_{MMSN}$) , Jupiter and Saturn get captured in 2:1 resonance and can even migrate outward in low-viscosity disks ($\\alpha \\le 10^{-4}$). Such disks have a very small aspect ratio ($h\\sim 0.02-0.03$) that favors outward migration after capture in 2:1 resonance, as confirmed by isothermal runs which resulted in a similar o...
Scafetta, Nicola
2012-01-01
The sunspot record since 1749 is made of three major cycles (9.98, 10.9 and 11.86 yr). The side frequencies are related to the spring tidal period of Jupiter and Saturn (9.93 yr) and to the tidal sidereal period of Jupiter (11.86 yr). A simplified harmonic constituent model based on the above two planetary tidal frequencies and on the exact dates of Jupiter and Saturn planetary tidal phases, plus a theoretically deduced 10.87-year central cycle reveals complex quasi-periodic interference/beat patterns at about 115, 61 and 130 years, plus a quasi-millennial large beat cycle around 983 years. We show that equivalent synchronized cycles are found in cosmogenic records used to reconstruct solar activity and in proxy climate records throughout the Holocene. The quasi-secular beat oscillations hindcast reasonably well the known prolonged periods of low solar activity during the last millennium known as Oort, Wolf, Sporer, Maunder and Dalton minima, as well as 17 115-year long oscillations found in temperature recon...
The extended RBAC model based on grid computing
Institute of Scientific and Technical Information of China (English)
CHEN Jian-gang; WANG Ru-chuan; WANG Hai-yan
2006-01-01
This article proposes the extended role-based access control (RBAC) model for solving dynamic and multidomain problems in grid computing, The formulated description of the model has been provided. The introduction of context and the mapping relations of context-to-role and context-to-permission help the model adapt to dynamic property in grid environment.The multidomain role inheritance relation by the authorization agent service realizes the multidomain authorization amongst the autonomy domain. A function has been proposed for solving the role inheritance conflict during the establishment of the multidomain role inheritance relation.
Constructing Multidatabase Collections Using Extended ODMG Object Model
Directory of Open Access Journals (Sweden)
Adrian Skehill Mark Roantree
1999-11-01
Full Text Available Collections are an important feature in database systems. They provide us with the ability to group objects of interest together, and then to manipulate them in the required fashion. The OASIS project is focused on the construction a multidatabase prototype which uses the ODMG model and a canonical model. As part of this work we have extended the base model to provide a more powerful collection mechanism, and to permit the construction of a federated collection, a collection of heterogenous objects taken from distributed data sources
Extended hard-sphere model and collisions of cohesive particles.
Kosinski, Pawel; Hoffmann, Alex C
2011-09-01
In two earlier papers the present authors modified a standard hard-sphere particle-wall and particle-particle collision model to account for the presence of adhesive or cohesive interaction between the colliding particles: the problem is of importance for modeling particle-fluid flow using the Lagrangian approach. This technique, which involves a direct numerical simulation of such flows, is gaining increasing popularity for simulating, e.g., dust transport, flows of nanofluids and grains in planetary rings. The main objective of the previous papers was to formally extend the impulse-based hard-sphere model, while suggestions for quantifications of the adhesive or cohesive interaction were made. This present paper gives an improved quantification of the adhesive and cohesive interactions for use in the extended hard-sphere model for cases where the surfaces of the colliding bodies are "dry," e.g., there is no liquid-bridge formation between the colliding bodies. This quantification is based on the Johnson-Kendall-Roberts (JKR) analysis of collision dynamics but includes, in addition, dissipative forces using a soft-sphere modeling technique. In this way the cohesive impulse, required for the hard-sphere model, is calculated together with other parameters, namely the collision duration and the restitution coefficient. Finally a dimensional analysis technique is applied to fit an analytical expression to the results for the cohesive impulse that can be used in the extended hard-sphere model. At the end of the paper we show some simulation results in order to illustrate the model.
Galanti, Eli; Durante, Daniele; Iess, Luciano; Kaspi, Yohai
2017-04-01
The ongoing Juno spacecraft measurements are improving our knowledge of Jupiter's gravity field. Similarly, the Cassini Grand Finale will improve the gravity estimate of Saturn. The analysis of the Juno and Cassini Doppler data will provide a very accurate reconstruction of spacial gravity variations, but these measurements will be very accurate only over a limited latitudinal range. In order to deduce the full gravity fields of Jupiter and Saturn, additional information needs to be incorporated into the analysis, especially with regards to the planets' wind structures. In this work we propose a new iterative approach for the estimation of Jupiter and Saturn gravity fields, using simulated measurements, a trajectory estimation model, and an adjoint based inverse thermal wind model. Beginning with an artificial gravitational field, the trajectory estimation model is used to obtain the gravitational moments. The solution from the trajectory model is then used as an initial guess for the thermal wind model, and together with an optimization method, the likely penetration depth of the winds is computed, and its uncertainty is evaluated. As a final step, the gravity harmonics solution from the thermal wind model is given back to the trajectory model, along with an estimate of their uncertainties, to be used as a priori for a new calculation of the gravity field. We test this method both for zonal harmonics only and with a full gravity field including tesseral harmonics. The results show that by using this method some of the gravitational moments are fitted better to the `observed' ones, mainly due to the added information from the dynamical model which includes the wind structure and its depth. Thus, it is suggested that the method presented here has the potential of improving the accuracy of the expected gravity moments estimated from the Juno and Cassini radio science experiments.
Negativity in the Extended Hubbard Model under External Magnetic Field
Institute of Scientific and Technical Information of China (English)
YANG Zhen; NING Wen-Qiang
2008-01-01
We exactly calculate the negativity,a measurement of entanglement,in the two-site extended Hubbard model with external magnetic field.Its behaviour at different temperatures is presented.The negativity reduces with the increasing temperature or with the increasing uniform external magnetic field.It is also found that a non-uniform external magnetic field can be used to modulate or to increase the negativity.
The one-dimensional extended Bose-Hubbard model
Indian Academy of Sciences (India)
Ramesh V Pai; Rahul Pandit
2003-10-01
We use the finite-size, density-matrix-renormalization-group (DMRG) method to obtain the zero-temperature phase diagram of the one-dimensional, extended Bose-Hubbard model, for mean boson density ρ = 1, in the - plane ( and are respectively, onsite and nearest-neighbour repulsive interactions between bosons). The phase diagram includes superfluid (SF), bosonic-Mott-insulator (MI), and mass-density-wave (MDW) phases. We determine the natures of the quantum phase transitions between these phases.
Extended gauge models at e+e- colliders
Djouadi, Abdelhak
1995-01-01
We summarize the potential of high--energy \\ee linear colliders for discovering, and in case of discovery, for studying the signals of extended gauge models. We will mainly focus on the virtual signals of new neutral gauge bosons and on the production of new heavy leptons. [Invited talk given at the Workshop on Physics and Experiments with Linear Colliders, Morioka-Appi, Japan, September 8-12 1995.
Model Calibration of Exciter and PSS Using Extended Kalman Filter
Energy Technology Data Exchange (ETDEWEB)
Kalsi, Karanjit; Du, Pengwei; Huang, Zhenyu
2012-07-26
Power system modeling and controls continue to become more complex with the advent of smart grid technologies and large-scale deployment of renewable energy resources. As demonstrated in recent studies, inaccurate system models could lead to large-scale blackouts, thereby motivating the need for model calibration. Current methods of model calibration rely on manual tuning based on engineering experience, are time consuming and could yield inaccurate parameter estimates. In this paper, the Extended Kalman Filter (EKF) is used as a tool to calibrate exciter and Power System Stabilizer (PSS) models of a particular type of machine in the Western Electricity Coordinating Council (WECC). The EKF-based parameter estimation is a recursive prediction-correction process which uses the mismatch between simulation and measurement to adjust the model parameters at every time step. Numerical simulations using actual field test data demonstrate the effectiveness of the proposed approach in calibrating the parameters.
Jupiter's Radiation Belts: Can Pioneer 10 Survive?
Hess, W N; Birmingham, T J; Mead, G D
1973-12-07
Model calculations of Jupiter's electron and proton radiation belts indicate that the Galilean satellites can reduce particle fluxes in certain regions of the inner magnetosphere by as much as six orders of magnitude. Average fluxes should be reduced by a factor of 100 or more along the Pioneer 10 trajectory through the heart of Jupiter's radiation belts in early December. This may be enough to prevent serious radiation damage to the spacecraft.
Extended superconformal symmetry, Freudenthal triple systems and gauged WZW models
Günaydin, M
1995-01-01
We review the construction of extended ( N=2 and N=4 ) superconformal algebras over triple systems and the gauged WZW models invariant under them. The N=2 superconformal algebras (SCA) realized over Freudenthal triple systems (FTS) admit extension to ``maximal'' N=4 SCA's with SU(2)XSU(2)XU(1) symmetry. A detailed study of the construction and classification of N=2 and N=4 SCA's over Freudenthal triple systems is given. We conclude with a study and classification of gauged WZW models with N=4 superconformal symmetry.
Extended cox regression model: The choice of timefunction
Isik, Hatice; Tutkun, Nihal Ata; Karasoy, Durdu
2017-07-01
Cox regression model (CRM), which takes into account the effect of censored observations, is one the most applicative and usedmodels in survival analysis to evaluate the effects of covariates. Proportional hazard (PH), requires a constant hazard ratio over time, is the assumptionofCRM. Using extended CRM provides the test of including a time dependent covariate to assess the PH assumption or an alternative model in case of nonproportional hazards. In this study, the different types of real data sets are used to choose the time function and the differences between time functions are analyzed and discussed.
An Extended Hierarchical Trusted Model for Wireless Sensor Networks
Institute of Scientific and Technical Information of China (English)
DU Ruiying; XU Mingdi; ZHANG Huanguo
2006-01-01
Cryptography and authentication are traditional approach for providing network security. However, they are not sufficient for solving the problems which malicious nodes compromise whole wireless sensor network leading to invalid data transmission and wasting resource by using vicious behaviors. This paper puts forward an extended hierarchical trusted architecture for wireless sensor network, and establishes trusted congregations by three-tier framework. The method combines statistics, economics with encrypt mechanism for developing two trusted models which evaluate cluster head nodes and common sensor nodes respectively. The models form logical trusted-link from command node to common sensor nodes and guarantees the network can run in secure and reliable circumstance.
The Change in Jupiter's Moment of Inertia due to Core Erosion and Planetary Contraction
Helled, Ravit
2012-01-01
We explore the change in Jupiter's normalized axial moment of inertia (NMOI) assuming that Jupiter undergoes core erosion. It is found that Jupiter's contraction combined with an erosion of 20 M_Earth from a primordial core of 30 M_Earth can change Jupiter's NMOI over time significantly. It is shown that Jupiter's NMOI could have changed from ~0.235 to ~0.264 throughout its evolution. We find that a NMOI value of ~0.235 as suggested by dynamical models (Ward & Canup, 2006, ApJ, 640, L91) could, in principle, be consistent with Jupiter's primordial internal structure. Low NMOI values, however, persist only for the first ~ 10^6 years of Jupiter's evolution. Re-evaluation of dynamical stability models as well as more sophisticated evolution models of Jupiter with core erosion seem to be required in order to provide more robust estimates for Jupiter's primordial NMOI.
Extending the Clapper-Yule model to rough printing supports.
Hébert, Mathieu; Hersch, Roger David
2005-09-01
The Clapper-Yule model is the only classical spectral reflection model for halftone prints that takes explicitly into account both the multiple internal reflections between the print-air interface and the paper substrate and the lateral propagation of light within the paper bulk. However, the Clapper-Yule model assumes a planar interface and does not take into account the roughness of the print surface. In order to extend the Clapper-Yule model to rough printing supports (e.g., matte coated papers or calendered papers), we model the print surface as a set of randomly oriented microfacets. The influence of the shadowing effect is evaluated and incorporated into the model. By integrating over all incident angles and facet orientations, we are able to express the internal reflectance of the rough interface as a function of the rms facet slope. By considering also the rough interface transmittances both for the incident light and for the emerging light, we obtain a generalization of the Clapper-Yule model for rough interfaces. The comparison between the classical Clapper-Yule model and the model extended to rough surfaces shows that the influence of the surface roughness on the predicted reflectance factor is small. For high-quality papers such as coated and calendered papers, as well as for low-quality papers such as newsprint or copy papers, the influence of surface roughness is negligible, and the classical Clapper-Yule model can be used to predict the halftone-print reflectance factors. The influence of roughness becomes significant only for very rough and thick nondiffusing coatings.
Parameter Estimation of the Extended Vasiček Model
Directory of Open Access Journals (Sweden)
Sanae RUJIVAN
2010-01-01
Full Text Available In this paper, an estimate of the drift and diffusion parameters of the extended Vasiček model is presented. The estimate is based on the method of maximum likelihood. We derive a closed-form expansion for the transition (probability density of the extended Vasiček process and use the expansion to construct an approximate log-likelihood function of a discretely sampled data of the process. Approximate maximum likelihood estimators (AMLEs of the parameters are obtained by maximizing the approximate log-likelihood function. The convergence of the AMLEs to the true maximum likelihood estimators is obtained by increasing the number of terms in the expansions with a small time step size.
Far infrared spectrophotometry of Jupiter and Saturn
Erickson, E. F.; Goorvitch, D.; Simpson, J. P.; Strecker, D. W.
1978-01-01
Infrared spectral measurements of Mars, Jupiter, and Saturn were obtained from 100 to 470 kaysers and, by taking Mars as a calibration source, brightness temperatures of Jupiter and Saturn were determined with approximately 5 kayser resolution. Internal luminosities were determined from the data and are reported to be approximately 8 times 10 to the minus tenth power of the sun's luminosity for Jupiter and approximately 3.6 times 10 to the minus tenth power of the sun's luminosity for Saturn. Comparison of data with spectra predicted by models suggests the need for an opacity source in addition to gaseous hydrogen and ammonia to help explain Jupiter's observed spectrum in the vicinity of 250 kaysers.
2007-01-01
The New Horizons Long Range Reconnaissance Imager (LORRI) took this photo of Jupiter at 20:42:01 UTC on January 9, 2007, when the spacecraft was 80 million kilometers (49.6 million miles) from the giant planet. The volcanic moon Io is to the left of the planet; the shadow of the icy moon Ganymede moves across Jupiter's northern hemisphere. Ganymede's average orbit distance from Jupiter is about 1 million kilometers (620,000 miles); Io's is 422,000 kilometers (262,000 miles). Both Io and Ganymede are larger than Earth's moon; Ganymede is larger than the planet Mercury.
Wave speeds in the macroscopic extended model for ultrarelativistic gases
Energy Technology Data Exchange (ETDEWEB)
Borghero, F., E-mail: borghero@unica.it [Dip. Matematica e Informatica, Università di Cagliari, Via Ospedale 72, 09124 Cagliari (Italy); Demontis, F., E-mail: fdemontis@unica.it [Dip. Matematica, Università di Cagliari, Viale Merello 92, 09123 Cagliari (Italy); Pennisi, S., E-mail: spennisi@unica.it [Dip. Matematica, Università di Cagliari, Via Ospedale 72, 09124 Cagliari (Italy)
2013-11-15
Equations determining wave speeds for a model of ultrarelativistic gases are investigated. This model is already present in literature; it deals with an arbitrary number of moments and it was proposed in the context of exact macroscopic approaches in Extended Thermodynamics. We find these results: the whole system for the determination of the wave speeds can be divided into independent subsystems which are expressed by linear combinations, through scalar coefficients, of tensors all of the same order; some wave speeds, but not all of them, are expressed by square roots of rational numbers; finally, we prove that these wave speeds for the macroscopic model are the same of those furnished by the kinetic model.
Wave speeds in the macroscopic extended model for ultrarelativistic gases
Energy Technology Data Exchange (ETDEWEB)
Borghero, F., E-mail: borghero@unica.it [Dip. Matematica e Informatica, Università di Cagliari, Via Ospedale 72, 09124 Cagliari (Italy); Demontis, F., E-mail: fdemontis@unica.it [Dip. Matematica, Università di Cagliari, Viale Merello 92, 09123 Cagliari (Italy); Pennisi, S., E-mail: spennisi@unica.it [Dip. Matematica, Università di Cagliari, Via Ospedale 72, 09124 Cagliari (Italy)
2013-11-15
Equations determining wave speeds for a model of ultrarelativistic gases are investigated. This model is already present in literature; it deals with an arbitrary number of moments and it was proposed in the context of exact macroscopic approaches in Extended Thermodynamics. We find these results: the whole system for the determination of the wave speeds can be divided into independent subsystems which are expressed by linear combinations, through scalar coefficients, of tensors all of the same order; some wave speeds, but not all of them, are expressed by square roots of rational numbers; finally, we prove that these wave speeds for the macroscopic model are the same of those furnished by the kinetic model.
General Friction Model Extended by the Effect of Strain Hardening
DEFF Research Database (Denmark)
Nielsen, Chris V.; Martins, Paulo A.F.; Bay, Niels
2016-01-01
An extension to the general friction model proposed by Wanheim and Bay [1] to include the effect of strain hardening is proposed. The friction model relates the friction stress to the fraction of real contact area by a friction factor under steady state sliding. The original model for the real co...... of friction in metal forming, where the material generally strain hardens. The extension of the model to cover strain hardening materials is validated by comparison to previously published experimental data.......An extension to the general friction model proposed by Wanheim and Bay [1] to include the effect of strain hardening is proposed. The friction model relates the friction stress to the fraction of real contact area by a friction factor under steady state sliding. The original model for the real......-ideally plastic material, and secondly, to extend the solution by the influence of material strain hardening. This corresponds to adding a new variable and, therefore, a new axis to the general friction model. The resulting model is presented in a combined function suitable for e.g. finite element modeling...
Warm Jupiters from Secular Planet–Planet Interactions
Petrovich, Cristobal; Tremaine, Scott
2016-10-01
Most warm Jupiters (gas-giant planets with 0.1 {{au}}≲ a≲ 1 au) have pericenter distances that are too large for significant orbital migration by tidal friction. We study the possibility that the warm Jupiters are undergoing secular eccentricity oscillations excited by an outer companion (a planet or star) in an eccentric and/or mutually inclined orbit. In this model, the warm Jupiters migrate periodically, in the high-eccentricity phase of the oscillation, but are typically observed at lower eccentricities. We show that in this model the steady-state eccentricity distribution of the warm Jupiters is approximately flat, which is consistent with the observed distribution if we restrict the sample to warm Jupiters with detected outer planetary companions. The eccentricity distribution of warm Jupiters without companions exhibits a peak at e≲ 0.2 that must be explained by a different formation mechanism. Based on a population synthesis study, we find that high-eccentricity migration excited by an outer planetary companion (1) can account for ∼ 20 % of the warm Jupiters and most of the warm Jupiters with e≳ 0.4; and (2) can produce most of the observed population of hot Jupiters, with a semimajor axis distribution that matches the observations, but fails to account adequately for ∼ 60 % of hot Jupiters with projected obliquities ≲ 20^\\circ . Thus ∼ 20 % of the warm Jupiters and ∼ 60 % of the hot Jupiters can be produced by high-eccentricity migration. We also provide predictions for the expected mutual inclinations and spin-orbit angles of the planetary systems with hot and warm Jupiters produced by high-eccentricity migration.
A Design and Implementation of the Extended Andorra Model
Lopes, Ricardo; Silva, Fernando
2011-01-01
Logic programming provides a high-level view of programming, giving implementers a vast latitude into what techniques to explore to achieve the best performance for logic programs. Towards obtaining maximum performance, one of the holy grails of logic programming has been to design computational models that could be executed efficiently and that would allow both for a reduction of the search space and for exploiting all the available parallelism in the application. These goals have motivated the design of the Extended Andorra Model, a model where goals that do not constrain non-deterministic goals can execute first. In this work we present and evaluate the Basic design for Extended Andorra Model (BEAM), a system that builds upon David H. D. Warren's original EAM with Implicit Control. We provide a complete description and implementation of the BEAM System as a set of rewrite and control rules. We present the major data structures and execution algorithms that are required for efficient execution, and evaluate...
Modeling the Interaction of Moist Convection with the Zonal Jets of Jupiter
Li, L.; Ingersoll, A. P.
2004-11-01
We use a reduced-gravity quasi-geostrophic model with a parameterization of moist convection that is based on Galileo and Cassini observations of lightning and convective storms (Little et al., 1999; Gierasch et al., 2000; Porco et al., 2003). The features of the jets we want to reproduce in the model include: (1) the curvature of the zonal jet profile, which violates the barotropic stability criterion near many of the westward jets (Ingersoll et al., 1981; Li et al., 2004), (2) the speed of the zonal jets, which is related to their width, given that the jets marginally violate the barotropic stability criterion, and (3) the sign of the eddy momentum flux, which is into the jets and tends to sustain them (Beebe et al., 1979; Ingersoll et al., 1981; Salyk et al., 2004). The features of moist convective storms that are taken from observation include: (1) the tendency of the storms to occur in the cyclonic belts, (2) the rapid divergence of horizontal velocity near the cloud tops, and (3) the lifetime of the storms, which is on average 4-5 days (Li et al., 2004). We find that moist convection leads to zonal jets in the upper layer, but the jets violate the barotropic stability criterion only if the flow in the deep underlying layer is westward. We can reproduce the chevron shape on the sides of the jets if we postulate that the clouds persist longer than the storms that produce them. We can reproduce the number and frequency of moist convection storms by assuming that they carry most of the planet's vertical heat flux (Gierasch et al., 2000). The NASA Planetary Atmospheres Program supported this research.
OSeMOSYS Energy Modeling Using an Extended UTOPIA Model
Lavigne, Denis
2017-01-01
The OSeMOSYS project offers open-access energy modeling to a wide audience. Its relative simplicity makes it appealing for academic research and governmental organizations to study the impacts of policy decisions on an energy system in the context of possibly severe greenhouse gases emissions limitations. OSeMOSYS is a tool that enhances the…
Thermometric Soots on Hot Jupiters?
Zahnle, K; Fortney, J J
2009-01-01
We use a 1D thermochemical and photochemical kinetics model to predict that the stratospheric chemistry of hot Jupiters should change dramatically as temperature drops from 1200 to 1000 K. At 1200 K methane is too unstable to reach the stratosphere in significant quantities, while thermal decomposition of water is a strong source of OH radicals that oxidize any hydrocarbons that do form to CO and CO$_2$. At 1000 K methane, although very reactive, survives long enough to reach the lower stratosphere, and the greater stability of water coupled with efficient scavenging of OH by H$_2$ raise the effective C/O ratio in the reacting gases above unity. Reduced products such as ethylene, acetylene, and hydrogen cyanide become abundant; such conditions favor polymerization and possible formation of PAHs and soots. Although low temperature is the most important factor favoring hydrocarbons in hot Jupiters, higher rates of vertical mixing and generally lower metallicities also favor organic synthesis. The peculiar prope...
Extended Neural Metastability in an Embodied Model of Sensorimotor Coupling
Directory of Open Access Journals (Sweden)
Miguel Aguilera
2016-09-01
Full Text Available The hypothesis that brain organization is based on mechanisms of metastable synchronization in neural assemblies has been popularized during the last decades of neuroscientific research. Nevertheless, the role of body and environment for understanding the functioning of metastable assemblies is frequently dismissed. The main goal of this paper is to investigate the contribution of sensorimotor coupling to neural and behavioural metastability using a minimal computational model of plastic neural ensembles embedded in a robotic agent in a behavioural preference task. Our hypothesis is that, under some conditions, the metastability of the system is not restricted to the brain but extends to the system composed by the interaction of brain, body and environment. We test this idea, comparing an agent in continuous interaction with its environment in a task demanding behavioural flexibility with an equivalent model from the point of view of 'internalist neuroscience'. A statistical characterization of our model and tools from information theory allows us to show how (1 the bidirectional coupling between agent and environment brings the system closer to a regime of criticality and triggers the emergence of additional metastable states which are not found in the brain in isolation but extended to the whole system of sensorimotor interaction, (2 the synaptic plasticity of the agent is fundamental to sustain open structures in the neural controller of the agent flexibly engaging and disengaging different behavioural patterns that sustain sensorimotor metastable states, and (3 these extended metastable states emerge when the agent generates an asymmetrical circular loop of causal interaction with its environment, in which the agent responds to variability of the environment at fast timescales while acting over the environment at slow timescales, suggesting the constitution of the agent as an autonomous entity actively modulating its sensorimotor coupling
Extended Neural Metastability in an Embodied Model of Sensorimotor Coupling
Aguilera, Miguel; Bedia, Manuel G.; Barandiaran, Xabier E.
2016-01-01
The hypothesis that brain organization is based on mechanisms of metastable synchronization in neural assemblies has been popularized during the last decades of neuroscientific research. Nevertheless, the role of body and environment for understanding the functioning of metastable assemblies is frequently dismissed. The main goal of this paper is to investigate the contribution of sensorimotor coupling to neural and behavioral metastability using a minimal computational model of plastic neural ensembles embedded in a robotic agent in a behavioral preference task. Our hypothesis is that, under some conditions, the metastability of the system is not restricted to the brain but extends to the system composed by the interaction of brain, body and environment. We test this idea, comparing an agent in continuous interaction with its environment in a task demanding behavioral flexibility with an equivalent model from the point of view of “internalist neuroscience.” A statistical characterization of our model and tools from information theory allow us to show how (1) the bidirectional coupling between agent and environment brings the system closer to a regime of criticality and triggers the emergence of additional metastable states which are not found in the brain in isolation but extended to the whole system of sensorimotor interaction, (2) the synaptic plasticity of the agent is fundamental to sustain open structures in the neural controller of the agent flexibly engaging and disengaging different behavioral patterns that sustain sensorimotor metastable states, and (3) these extended metastable states emerge when the agent generates an asymmetrical circular loop of causal interaction with its environment, in which the agent responds to variability of the environment at fast timescales while acting over the environment at slow timescales, suggesting the constitution of the agent as an autonomous entity actively modulating its sensorimotor coupling with the world. We
Federal Laboratory Consortium — The Jupiter Laser Facility is an institutional user facility in the Physical and Life Sciences Directorate at LLNL. The facility is designed to provide a high degree...
Institute of Scientific and Technical Information of China (English)
诸葛勤
1994-01-01
The initial sketchy reports began filtering into the U. S. by E-maillate Saturday afternoon. First a Spanish observatory announced that it hadspotted a plume of gas billowing up from the edge of Jupiter. Then a
Extending the transdiagnostic model of attachment and psychopathology
Directory of Open Access Journals (Sweden)
Tsachi eEin-Dor
2016-03-01
Full Text Available Research has suggested that high levels of attachment insecurities that are formed through interactions with significant others are associated with a general vulnerability to mental disorders. In the present paper, we extend Ein-Dor and Doron's (2015 transdiagnostic model linking attachment orientations with internalizing and externalizing symptoms, to include thought disorder spectrum symptoms. Specifically, we speculate on the processes that mediate the linkage between attachment insecurities and psychosis and obsessive compulsive disorder (OCD symptoms, and indicate the different contexts that might set a trajectory of one individual to one set of symptoms while another individual to a different set of symptoms.
Extended Bayesian Information Criteria for Gaussian Graphical Models
Foygel, Rina
2010-01-01
Gaussian graphical models with sparsity in the inverse covariance matrix are of significant interest in many modern applications. For the problem of recovering the graphical structure, information criteria provide useful optimization objectives for algorithms searching through sets of graphs or for selection of tuning parameters of other methods such as the graphical lasso, which is a likelihood penalization technique. In this paper we establish the consistency of an extended Bayesian information criterion for Gaussian graphical models in a scenario where both the number of variables p and the sample size n grow. Compared to earlier work on the regression case, our treatment allows for growth in the number of non-zero parameters in the true model, which is necessary in order to cover connected graphs. We demonstrate the performance of this criterion on simulated data when used in conjunction with the graphical lasso, and verify that the criterion indeed performs better than either cross-validation or the ordi...
Extended Nonnegative Tensor Factorisation Models for Musical Sound Source Separation
Directory of Open Access Journals (Sweden)
Derry FitzGerald
2008-01-01
Full Text Available Recently, shift-invariant tensor factorisation algorithms have been proposed for the purposes of sound source separation of pitched musical instruments. However, in practice, existing algorithms require the use of log-frequency spectrograms to allow shift invariance in frequency which causes problems when attempting to resynthesise the separated sources. Further, it is difficult to impose harmonicity constraints on the recovered basis functions. This paper proposes a new additive synthesis-based approach which allows the use of linear-frequency spectrograms as well as imposing strict harmonic constraints, resulting in an improved model. Further, these additional constraints allow the addition of a source filter model to the factorisation framework, and an extended model which is capable of separating mixtures of pitched and percussive instruments simultaneously.
Southwood, D. J.; Kivelson, M. G.
Scenarios are presented for the overall flux and mass circulation in the jovian and saturnian magnetospheres It is argued that similar fundamanetal processes underly the dynamical processes at both planets However the differences in parameter regime for the two systems leads to substantial resulting differences in morphology Transport is accomplished from the inner magnetosphere by interchange motion which then feeds into the outer magnetosphere where ballooning driven by centrifugal stress leads to field reconnection and plasma loss It seems likely that Jupiter loses much more material per rotation cycle than Saturn and is possibly much more symmetrically loaded in respect of planetary longitude Material loss and flux return at Jupiter have fixed orientations in local time early evening and morning sector respectively and newly returned flux is probably responsible for the morningside cushion region in the outer magnetosphere At Jupiter the dawn-dusk asymmetry in the current sheet thin in morning thick in afternoon is also a dominant feature At Saturn there seems no evidence of a cushion region flux return is thought to take place sporadically over much of the nightside Although definitive statements about the dusk plasma sheet await the orbit evolution of Cassini a fundamental observational feature in the Saturnian context is a planetary rotation induced magnetic field asymmetry which argues against major dawn-dusk asymmetry We propose the rotational feature could originate from a localized ionospheric magnetic anomaly The
An Extended Clustering Algorithm for Statistical Language Models
Ueberla, J P
1994-01-01
Statistical language models frequently suffer from a lack of training data. This problem can be alleviated by clustering, because it reduces the number of free parameters that need to be trained. However, clustered models have the following drawback: if there is ``enough'' data to train an unclustered model, then the clustered variant may perform worse. On currently used language modeling corpora, e.g. the Wall Street Journal corpus, how do the performances of a clustered and an unclustered model compare? While trying to address this question, we develop the following two ideas. First, to get a clustering algorithm with potentially high performance, an existing algorithm is extended to deal with higher order N-grams. Second, to make it possible to cluster large amounts of training data more efficiently, a heuristic to speed up the algorithm is presented. The resulting clustering algorithm can be used to cluster trigrams on the Wall Street Journal corpus and the language models it produces can compete with exi...
Conformal standard model with an extended scalar sector
Energy Technology Data Exchange (ETDEWEB)
Latosiński, Adam [Max-Planck-Institut für Gravitationsphysik (Albert-Einstein-Institut),Mühlenberg 1, D-14476 Potsdam (Germany); Lewandowski, Adrian; Meissner, Krzysztof A. [Faculty of Physics, University of Warsaw,Pasteura 5, 02-093 Warsaw (Poland); Nicolai, Hermann [Max-Planck-Institut für Gravitationsphysik (Albert-Einstein-Institut),Mühlenberg 1, D-14476 Potsdam (Germany)
2015-10-26
We present an extended version of the Conformal Standard Model (characterized by the absence of any new intermediate scales between the electroweak scale and the Planck scale) with an enlarged scalar sector coupling to right-chiral neutrinos. The scalar potential and the Yukawa couplings involving only right-chiral neutrinos are invariant under a new global symmetry SU(3){sub N} that complements the standard U(1){sub B−L} symmetry, and is broken explicitly only by the Yukawa interaction, of order O(10{sup −6}), coupling right-chiral neutrinos and the electroweak lepton doublets. We point out four main advantages of this enlargement, namely: (1) the economy of the (non-supersymmetric) Standard Model, and thus its observational success, is preserved; (2) thanks to the enlarged scalar sector the RG improved one-loop effective potential is everywhere positive with a stable global minimum, thereby avoiding the notorious instability of the Standard Model vacuum; (3) the pseudo-Goldstone bosons resulting from spontaneous breaking of the SU(3){sub N} symmetry are natural Dark Matter candidates with calculable small masses and couplings; and (4) the Majorana Yukawa coupling matrix acquires a form naturally adapted to leptogenesis. The model is made perturbatively consistent up to the Planck scale by imposing the vanishing of quadratic divergences at the Planck scale (‘softly broken conformal symmetry’). Observable consequences of the model occur mainly via the mixing of the new scalars and the standard model Higgs boson.
Applying the Extended Parallel Process Model to workplace safety messages.
Basil, Michael; Basil, Debra; Deshpande, Sameer; Lavack, Anne M
2013-01-01
The extended parallel process model (EPPM) proposes fear appeals are most effective when they combine threat and efficacy. Three studies conducted in the workplace safety context examine the use of various EPPM factors and their effects, especially multiplicative effects. Study 1 was a content analysis examining the use of EPPM factors in actual workplace safety messages. Study 2 experimentally tested these messages with 212 construction trainees. Study 3 replicated this experiment with 1,802 men across four English-speaking countries-Australia, Canada, the United Kingdom, and the United States. The results of these three studies (1) demonstrate the inconsistent use of EPPM components in real-world work safety communications, (2) support the necessity of self-efficacy for the effective use of threat, (3) show a multiplicative effect where communication effectiveness is maximized when all model components are present (severity, susceptibility, and efficacy), and (4) validate these findings with gory appeals across four English-speaking countries.
Modeling the heterogeneous intestinal absorption of propiverine extended-release.
Weiss, Michael; Sermsappasuk, Pakawadee; Siegmund, Werner
2015-08-30
Propiverine is a widely used antimuscarinic drug with bioavailability that is limited by intestinal first-pass extraction. To study the apparent heterogeneity in intestinal first-pass extraction, we performed a population analysis of oral concentration-time data measured after administration of an extended-release formulation of propiverine in ten healthy subjects. Using an inverse Gaussian function as input model, the assumption that the systemically available fraction increases as a sigmoidal function of time considerably improved the fit. The step-like increase in this fraction at time t=3.7h predicted by the model suggests that propiverine is predominantly absorbed in colon. A nearly perfect correlation was found between the estimates of bioavailability and mean dissolution time. Copyright © 2015 Elsevier B.V. All rights reserved.
Extended Holstein polaron model for charge transfer in dry DNA
Institute of Scientific and Technical Information of China (English)
Liu Tao; Wang Yi; Wang Ke-Lin
2007-01-01
The variational method is applied to the study of charge transfer in dry DNA by using an extended Holstein small polaron model in two cases: the site-dependent finite-chain discrete case and the site-independent continuous one. The treatments in the two cases are proven to be consistent in theory and calculation. Discrete and continuous treatments of Holstein model both can yield a nonlinear equation to describe the charge migration in an actual long-range DNA chain.Our theoretical results of binding energy Eb, probability amplitude of charge carrier φ and the relation between energy and charge-lattice coupling strength are in accordance with the available experimental results and recent theoretical calculations.
Gutzwiller study of extended Hubbard models with fixed boson densities
Energy Technology Data Exchange (ETDEWEB)
Kimura, Takashi [Department of Information Sciences, Kanagawa University, 2946 Tsuchiya, Hiratsuka, Kanagawa 259-1293 (Japan)
2011-12-15
We studied all possible ground states, including supersolid (SS) phases and phase separations of hard-core- and soft-core-extended Bose-Hubbard models with fixed boson densities by using the Gutzwiller variational wave function and the linear programming method. We found that the phase diagram of the soft-core model depends strongly on its transfer integral. Furthermore, for a large transfer integral, we showed that an SS phase can be the ground state even below or at half filling against the phase separation. We also found that the density difference between nearest-neighbor sites, which indicates the density order of the SS phase, depends strongly on the boson density and transfer integral.
Extended Group Contribution Model for Polyfunctional Phase Equilibria
DEFF Research Database (Denmark)
Abildskov, Jens
-liquid equilibria from data on binary mixtures, composed of structurally simple molecules with a single functional group. More complex is the situation with mixtures composed of structurally more complicated molecules or molecules with more than one functional group. The UNIFAC method is extended to handle...... polyfunctional group situations, based on additional information on molecular structure. The extension involves the addition of second-order correction terms to the existing equation. In this way the current first-order formulation is retained. The second-order concept is developed for mixture properties based....... In chapter 4 parameters are estimated for the first-order UNIFAC model, based on which parameters are estimated for one of the second-order models described in chapter 3. The parameter estimation is based on measured binary data on around 4000 systems, covering 11 C-, H- and O-containing functional groups...
Analysis of the phase structure in extended Higgs models
Energy Technology Data Exchange (ETDEWEB)
Seniuch, M.
2006-07-07
We study the generation of the baryon asymmetry in the context of electroweak baryogenesis in two different extensions of the Standard Model. First, we consider an effective theory, in which the Standard Model is augmented by an additional dimension-six Higgs operator. The effects of new physics beyond a cut-off scale are parameterized by this operator. The second model is the two-Higgs-doublet model, whose particle spectrum is extended by two further neutral and two charged heavy Higgs bosons. In both cases we focus on the properties of the electroweak phase transition, especially on its strength and the profile of the nucleating bubbles. After reviewing some general aspects of the electroweak phase transition and baryogenesis we derive the respective thermal effective potentials to one-loop order. We systematically study the parameter spaces, using numerical methods, and compute the strength of the phase transition and the wall thickness as a function of the Higgs masses. We find a strong first order transition for a light Higgs state with a mass up to about 200 GeV. In case of the dimension-six model the cut-off scale has to stay between 500 and 850 GeV, in the two-Higgs-doublet model one needs at least one heavy Higgs mass of 300 GeV. The wall thickness varies for both theories in the range roughly from two to fifteen, in units of the inverse critical temperature. We also estimate the size of the electron and neutron electric dipole moments, since new sources of CP violation give rise to them. In wide ranges of the parameter space we are not in conflict with the experimental bounds. Finally the baryon asymmetry, which is predicted by these models, is related to the Higgs mass and the other appropriate input parameters. In both models the measured baryon asymmetry can be achieved for natural values of the model parameters. (orig.)
Extended nonlinear feedback model for describing episodes of high inflation
Szybisz, Martín A.; Szybisz, Leszek
2017-01-01
An extension of the nonlinear feedback (NLF) formalism to describe regimes of hyper- and high-inflation in economy is proposed in the present work. In the NLF model the consumer price index (CPI) exhibits a finite time singularity of the type 1 /(tc - t) (1 - β) / β, with β > 0, predicting a blow up of the economy at a critical time tc. However, this model fails in determining tc in the case of weak hyperinflation regimes like, e.g., that occurred in Israel. To overcome this trouble, the NLF model is extended by introducing a parameter γ, which multiplies all terms with past growth rate index (GRI). In this novel approach the solution for CPI is also analytic being proportional to the Gaussian hypergeometric function 2F1(1 / β , 1 / β , 1 + 1 / β ; z) , where z is a function of β, γ, and tc. For z → 1 this hypergeometric function diverges leading to a finite time singularity, from which a value of tc can be determined. This singularity is also present in GRI. It is shown that the interplay between parameters β and γ may produce phenomena of multiple equilibria. An analysis of the severe hyperinflation occurred in Hungary proves that the novel model is robust. When this model is used for examining data of Israel a reasonable tc is got. High-inflation regimes in Mexico and Iceland, which exhibit weaker inflations than that of Israel, are also successfully described.
Extended Nambu models: Their relation to gauge theories
Escobar, C. A.; Urrutia, L. F.
2017-05-01
Yang-Mills theories supplemented by an additional coordinate constraint, which is solved and substituted in the original Lagrangian, provide examples of the so-called Nambu models, in the case where such constraints arise from spontaneous Lorentz symmetry breaking. Some explicit calculations have shown that, after additional conditions are imposed, Nambu models are capable of reproducing the original gauge theories, thus making Lorentz violation unobservable and allowing the interpretation of the corresponding massless gauge bosons as the Goldstone bosons arising from the spontaneous symmetry breaking. A natural question posed by this approach in the realm of gauge theories is to determine under which conditions the recovery of an arbitrary gauge theory from the corresponding Nambu model, defined by a general constraint over the coordinates, becomes possible. We refer to these theories as extended Nambu models (ENM) and emphasize the fact that the defining coordinate constraint is not treated as a standard gauge fixing term. At this level, the mechanism for generating the constraint is irrelevant and the case of spontaneous Lorentz symmetry breaking is taken only as a motivation, which naturally bring this problem under consideration. Using a nonperturbative Hamiltonian analysis we prove that the ENM yields the original gauge theory after we demand current conservation for all time, together with the imposition of the Gauss laws constraints as initial conditions upon the dynamics of the ENM. The Nambu models yielding electrodynamics, Yang-Mills theories and linearized gravity are particular examples of our general approach.
Streamflow Data Assimilation in SWAT Model Using Extended Kalman Filter
Sun, L.; Nistor, I.; Seidou, O.
2014-12-01
Although Extended Kalman Filter (EKF) is regarded as the de facto method for the application of Kalman Filter in non-linear system, it's application to complex distributed hydrological models faces a lot of challenges. Ensemble Kalman Filter (EnKF) is often preferred because it avoids the calculation of the linearization Jacobian Matrix and the propagation of estimation error covariance. EnKF is however difficult to apply to large models because of the huge computation demand needed for parallel propagation of ensemble members. This paper deals with the application of EKF in stream flow prediction using the SWAT model in the watershed of Senegal River, West Africa. In the Jacobian Matrix calculation, SWAT is regarded as a black box model and the derivatives are calculated in the form of differential equations. The state vector is the combination of runoff, soil, shallow aquifer and deep aquifer water contents. As an initial attempt, only stream flow observations are assimilated. Despite the fact that EKF is a sub-optimal filter, the coupling of EKF significantly improves the estimation of daily streamflow. The results of SWAT+EKF are also compared to those of a simpler quasi linear streamflow prediction model where both state and parameters are updated with the EKF.
Jupiter internal structure: the effect of different equations of state
Miguel, Y.; Guillot, T.; Fayon, L.
2016-12-01
Context. Heavy elements, even though they are a smaller constituent, are crucial to understand the formation history of Jupiter. Interior models are used to determine the amount of heavy elements in the interior of Jupiter, but this range is still subject to degeneracies because of the uncertainties in the equations of state. Aims: Before Juno mission data arrive, we present optimized calculations for Jupiter that explore the effect of different model parameters on the determination of the core and the mass of heavy elements of Jupiter. We compare recently published equations of state. Methods: The interior model of Jupiter was calculated from the equations of hydrostatic equilibrium, mass, and energy conservation, and energy transport. The mass of the core and heavy elements was adjusted to match the observed radius and gravitational moments of Jupiter. Results: We show that the determination of the interior structure of Jupiter is tied to the estimation of its gravitational moments and the accuracy of equations of state of hydrogen, helium, and heavy elements. Locating the region where helium rain occurs and defining its timescale is important to determine the distribution of heavy elements and helium in the interior of Jupiter. We show that the differences found when modeling the interior of Jupiter with recent EOS are more likely due to differences in the internal energy and entropy calculation. The consequent changes in the thermal profile lead to different estimates of the mass of the core and heavy elements, which explains differences in recently published interior models of Jupiter. Conclusions: Our results help clarify the reasons for the differences found in interior models of Jupiter and will help interpreting upcoming Juno data. Full appendix tables are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/596/A114
Extended duration local anesthetic agent in a rat paw model.
Ickowicz, D E; Golovanevski, L; Domb, A J; Weiniger, C F
2014-07-01
Encapsulated local anesthetics extend postoperative analgesic effect following site-directed nerve injection; potentially reducing postoperative complications. Our study aim was to investigate efficacy of our improved extended duration formulation - 15% bupivacaine in poly(DL-lactic acid co castor oil) 3:7 synthesized by ring opening polymerization. In vitro, around 70% of bupivacaine was released from the p(DLLA-CO) 3:7 after 10 days. A single injection of the optimal formulation of 15% bupivacaine-polymer or plain (0.5%) bupivacaine (control), was injected via a 22G needle beside the sciatic nerve of Sprague-Dawley rats under anesthesia; followed (in some animals) by a 1cm longitudinal incision through the skin and fascia of the paw area. Behavioral tests for sensory and motor block assessment were done using Hargreave's hot plate score, von Frey filaments and rearing count. The 15% bupivacaine formulation significantly prolonged sensory block duration up to at least 48 h. Following surgery, motor block was observed for 48 h following administration of bupivacaine-polymer formulation and rearing was reduced (returning to baseline after 48 h). No significant differences in mechanical nociceptive response were observed. The optimized bupivacaine-polymer formulation prolonged duration of local anesthesia effect in our animal model up to at least 48 h.
Warm Jupiters Are Less Lonely than Hot Jupiters: Close Neighbors
Huang, Chelsea; Wu, Yanqin; Triaud, Amaury H. M. J.
2016-07-01
Exploiting the Kepler transit data, we uncover a dramatic distinction in the prevalence of sub-Jovian companions between systems that contain hot Jupiters (HJs) (periods inward of 10 days) and those that host warm Jupiters (WJs) (periods between 10 and 200 days). HJs, with the singular exception of WASP-47b, do not have any detectable inner or outer planetary companions (with periods inward of 50 days and sizes down to 2 R Earth). Restricting ourselves to inner companions, our limits reach down to 1 R Earth. In stark contrast, half of the WJs are closely flanked by small companions. Statistically, the companion fractions for hot and WJs are mutually exclusive, particularly in regard to inner companions. The high companion fraction of WJs also yields clues to their formation. The WJs that have close-by siblings should have low orbital eccentricities and low mutual inclinations. The orbital configurations of these systems are reminiscent of those of the low-mass close-in planetary systems abundantly discovered by the Kepler mission. This, and other arguments, lead us to propose that these WJs are formed in situ. There are indications that there may be a second population of WJs with different characteristics. In this picture, WASP-47b could be regarded as the extending tail of the in situ WJs into the HJ region and does not represent the generic formation route for HJs.
A multifluid model extended for strong temperature nonequilibrium
Energy Technology Data Exchange (ETDEWEB)
Chang, Chong [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2016-08-08
We present a multifluid model in which the material temperature is strongly affected by the degree of segregation of each material. In order to track temperatures of segregated form and mixed form of the same material, they are defined as different materials with their own energy. This extension makes it necessary to extend multifluid models to the case in which each form is defined as a separate material. Statistical variations associated with the morphology of the mixture have to be simplified. Simplifications introduced include combining all molecularly mixed species into a single composite material, which is treated as another segregated material. Relative motion within the composite material, diffusion, is represented by material velocity of each component in the composite material. Compression work, momentum and energy exchange, virtual mass forces, and dissipation of the unresolved kinetic energy have been generalized to the heterogeneous mixture in temperature nonequilibrium. The present model can be further simplified by combining all mixed forms of materials into a composite material. Molecular diffusion in this case is modeled by the Stefan-Maxwell equations.
How Stueckelberg Extends the Standard Model and the MSSM
Körs, B; Kors, Boris; Nath, Pran
2005-01-01
Abelian vector bosons can get massive through the Stueckelberg mechanism without spontaneous symmetry breaking via condensation of Higgs scalar fields. This appears very naturally in models derived from string theory and supergravity. The simplest scenarios of this type consist of extensions of the Standard Model (SM) or the minimal supersymmetric standard model (MSSM) by an extra U(1)_X gauge group with Stueckelberg type couplings. For the SM, the physical spectrum is extended by a massive neutral gauge boson Z' only, while the extension of the MSSM contains a CP-even neutral scalar and two extra neutralinos. The new gauge boson Z' can be very light compared to other models with U(1)' extensions. Among the new features of the Stueckelberg extension of the MSSM, the most striking is the possibility of a new lightest supersymmetric particle (LSP) chi_{St}^0 which is mostly composed of Stueckelberg fermions. In this scenario the LSP of the MSSM chi_1^0 is unstable and decays into chi_{St}^0. Such decays alter t...
"Let's Move" campaign: applying the extended parallel process model.
Batchelder, Alicia; Matusitz, Jonathan
2014-01-01
This article examines Michelle Obama's health campaign, "Let's Move," through the lens of the extended parallel process model (EPPM). "Let's Move" aims to reduce the childhood obesity epidemic in the United States. Developed by Kim Witte, EPPM rests on the premise that people's attitudes can be changed when fear is exploited as a factor of persuasion. Fear appeals work best (a) when a person feels a concern about the issue or situation, and (b) when he or she believes to have the capability of dealing with that issue or situation. Overall, the analysis found that "Let's Move" is based on past health campaigns that have been successful. An important element of the campaign is the use of fear appeals (as it is postulated by EPPM). For example, part of the campaign's strategies is to explain the severity of the diseases associated with obesity. By looking at the steps of EPPM, readers can also understand the strengths and weaknesses of "Let's Move."
Postcorrection and mathematical model of life in Extended Everett's Concept
Mensky, Michael B
2007-01-01
Extended Everett's Concept (EEC) recently developed by the author to explain the phenomenon of consciousness is considered. A mathematical model is proposed for the principal feature of consciousness assumed in EEC, namely its ability (in the state of sleep, trance or meditation, when the explicit consciousness is disabled) to obtain information from all alternative classical realities (Everett's worlds) and select the favorable realities. To represent this ability, a mathematical operation called postcorrection is introduced, which corrects the present state to guarantee certain characteristics of the future state. Evolution of living matter is thus determined by goals (first of all by the goal of survival) as well as by causes. The resulting theory, in a way symmetrical in time direction, follows from a sort of antropic principle. Possible criteria for postcorrection and corresponding phenomena in the sphere of life are classified. Both individual and collective criteria of survival are considered as well a...
DCC&U: An Extended Digital Curation Lifecycle Model
Directory of Open Access Journals (Sweden)
Panos Constantopoulos
2009-06-01
Full Text Available Normal 0 The proliferation of Web, database and social networking technologies has enabled us to produce, publish and exchange digital assets at an enormous rate. This vast amount of information that is either digitized or born-digital needs to be collected, organized and preserved in a way that ensures that our digital assets and the information they carry remain available for future use. Digital curation has emerged as a new inter-disciplinary practice that seeks to set guidelines for disciplined management of information. In this paper we review two recent models for digital curation introduced by the Digital Curation Centre (DCC and the Digital Curation Unit (DCU of the Athena Research Centre. We then propose a fusion of the two models that highlights the need to extend the digital curation lifecycle by adding (a provisions for the registration of usage experience, (b a stage for knowledge enhancement and (c controlled vocabularies used by convention to denote concepts, properties and relations. The objective of the proposed extensions is twofold: (i to provide a more complete lifecycle model for the digital curation domain; and (ii to provide a stimulus for a broader discussion on the research agenda.
New extended standard model, dark matters and relativity theory
Hwang, Jae-Kwang
2016-03-01
Three-dimensional quantized space model is newly introduced as the extended standard model. Four three-dimensional quantized spaces with total 12 dimensions are used to explain the universes including ours. Electric (EC), lepton (LC) and color (CC) charges are defined to be the charges of the x1x2x3, x4x5x6 and x7x8x9 warped spaces, respectively. Then, the lepton is the xi(EC) - xj(LC) correlated state which makes 3x3 = 9 leptons and the quark is the xi(EC) - xj(LC) - xk(CC) correlated state which makes 3x3x3 = 27 quarks. The new three bastons with the xi(EC) state are proposed as the dark matters seen in the x1x2x3 space, too. The matter universe question, three generations of the leptons and quarks, dark matter and dark energy, hadronization, the big bang, quantum entanglement, quantum mechanics and general relativity are briefly discussed in terms of this new model. The details can be found in the article titled as ``journey into the universe; three-dimensional quantized spaces, elementary particles and quantum mechanics at https://www.researchgate.net/profile/J_Hwang2''.
Capture of Trojans by Jumping Jupiter
Nesvorny, David; Morbidelli, Alessandro
2013-01-01
Jupiter Trojans are thought to be survivors of a much larger population of planetesimals that existed in the planetary region when planets formed. They can provide important constraints on the mass and properties of the planetesimal disk, and its dispersal during planet migration. Here we tested a possibility that the Trojans were captured during the early dynamical instability among the outer planets (aka the Nice model), when the semimajor axis of Jupiter was changing as a result of scattering encounters with an ice giant. The capture occurs in this model when Jupiter's orbit and its Lagrange points become radially displaced in a scattering event and fall into a region populated by planetesimals (that previously evolved from their natal transplanetary disk to ~5 AU during the instability). Our numerical simulations of the new capture model, hereafter jump capture, satisfactorily reproduce the orbital distribution of the Trojans and their total mass. The jump capture is potentially capable of explaining the ...
Jupiter's magnetosphere and radiation belts
Kennel, C. F.; Coroniti, F. V.
1979-01-01
Radioastronomy and Pioneer data reveal the Jovian magnetosphere as a rotating magnetized source of relativistic particles and radio emission, comparable to astrophysical cosmic ray and radio sources, such as pulsars. According to Pioneer data, the magnetic field in the outer magnetosphere is radially extended into a highly time variable disk-shaped configuration which differs fundamentally from the earth's magnetosphere. The outer disk region, and the energetic particles confined in it, are modulated by Jupiter's 10 hr rotation period. The entire outer magnetosphere appears to change drastically on time scales of a few days to a week. In addition to its known modulation of the Jovian decametric radio bursts, Io was found to absorb some radiation belt particles and to accelerate others, and most importantly, to be a source of neutral atoms, and by inference, a heavy ion plasma which may significantly affect the hydrodynamic flow in the magnetosphere. Another important Pioneer finding is that the Jovian outer magnetosphere generates, or permits to escape, fluxes of relativistic electrons of such intensities that Jupiter may be regarded as the dominant source of 1 to 30 MeV cosmic ray electrons in the heliosphere.
Study of a 30-M Boom For Solar Sail-Craft: Model Extendibility and Control Strategy
Keel, Leehyun
2005-01-01
Space travel propelled by solar sails is motivated by the fact that the momentum exchange that occurs when photons are reflected and/or absorbed by a large solar sail generates a small but constant acceleration. This acceleration can induce a constant thrust in very large sails that is sufficient to maintain a polar observing satellite in a constant position relative to the Sun or Earth. For long distance propulsion, square sails (with side length greater than 150 meters) can reach Jupiter in two years and Pluto in less than ten years. Converting such design concepts to real-world systems will require accurate analytical models and model parameters. This requires extensive structural dynamics tests. However, the low mass and high flexibility of large and light weight structures such as solar sails makes them unsuitable for ground testing. As a result, validating analytical models is an extremely difficult problem. On the other hand, a fundamental question can be asked. That is whether an analytical model that represents a small-scale version of a solar-sail boom can be extended to much larger versions of the same boom. To answer this question, we considered a long deployable boom that will be used to support the solar sails of the sail-craft. The length of fully deployed booms of the actual solar sail-craft will exceed 100 meters. However, the test-bed we used in our study is a 30 meter retractable boom at MSFC. We first develop analytical models based on Lagrange s equations and the standard Euler-Bernoulli beam. Then the response of the models will be compared with test data of the 30 meter boom at various deployed lengths. For this stage of study, our analysis was limited to experimental data obtained at 12ft and 18ft deployment lengths. The comparison results are positive but speculative. To observe properly validate the analytic model, experiments at longer deployment lengths, up to the full 30 meter, have been requested. We expect the study to answer the
Energy Technology Data Exchange (ETDEWEB)
Kikuchi, Akihiro; Higuchi, Arika [Department of Earth and Planetary Sciences, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8551 (Japan); Ida, Shigeru, E-mail: kikuchi.a@geo.titech.ac.jp, E-mail: higuchia@geo.titech.ac.jp, E-mail: ida@elsi.jp [Earth-Life Science Institute, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8550 (Japan)
2014-12-10
Recently, gas giant planets in nearly circular orbits with large semimajor axes (a ∼ 30-1000 AU) have been detected by direct imaging. We have investigated orbital evolution in a formation scenario for such planets, based on a core accretion model. (1) Icy cores accrete from planetesimals at ≲ 30 AU, (2) they are scattered outward by an emerging nearby gas giant to acquire highly eccentric orbits, and (3) their orbits are circularized through the accretion of disk gas in outer regions, where they spend most of their time. We analytically derived equations to describe the orbital circularization through gas accretion. Numerical integrations of these equations show that the eccentricity decreases by a factor of more than 5 while the planetary mass increases by a factor of 10. Because runaway gas accretion increases planetary mass by ∼10-300, the orbits are sufficiently circularized. On the other hand, a is reduced at most only by a factor of two, leaving the planets in the outer regions. If the relative velocity damping by shock is considered, the circularization slows down, but is still efficient enough. Therefore, this scenario potentially accounts for the formation of observed distant jupiters in nearly circular orbits. If the apocenter distances of the scattered cores are larger than the disk sizes, their a shrink to a quarter of the disk sizes; the a-distribution of distant giants could reflect the outer edges of the disks in a similar way that those of hot jupiters may reflect inner edges.
Horner, J.; Jones, B. W.
2007-08-01
Throughout both popular science and academia, there is a pervasive belief that Jupiter has acted as a celestial shield, reducing the impact rate on the Earth, and making the planet a significantly more conducive site for the evolution and survival of life. This old idea has, however, undergone little detailed scrutiny. In the first of a series of studies aimed at a better understanding of this idea, we examine the variation in the impact rate on the Earth which results from bodies moving inwards from the Edgeworth- Kuiper belt as a function of the mass of a giant planet in Jupiter's orbit. The results are not entirely what would be expected under the "Jupiter Shield" paradigm.
2008-10-01
New image-correction technique delivers sharpest whole-planet ground-based picture ever A record two-hour observation of Jupiter using a superior technique to remove atmospheric blur has produced the sharpest whole-planet picture ever taken from the ground. The series of 265 snapshots obtained with the Multi-Conjugate Adaptive Optics Demonstrator (MAD) prototype instrument mounted on ESO's Very Large Telescope (VLT) reveal changes in Jupiter's smog-like haze, probably in response to a planet-wide upheaval more than a year ago. Sharpening Up Jupiter ESO PR Photo 33/08 Sharpening Up Jupiter Being able to correct wide field images for atmospheric distortions has been the dream of scientists and engineers for decades. The new images of Jupiter prove the value of the advanced technology used by MAD, which uses two or more guide stars instead of one as references to remove the blur caused by atmospheric turbulence over a field of view thirty times larger than existing techniques [1]. "This type of adaptive optics has a big advantage for looking at large objects, such as planets, star clusters or nebulae," says lead researcher Franck Marchis, from UC Berkeley and the SETI Institute in Mountain View, California, USA. "While regular adaptive optics provides excellent correction in a small field of view, MAD provides good correction over a larger area of sky. And in fact, were it not for MAD, we would not have been able to perform these amazing observations." MAD allowed the researchers to observe Jupiter for almost two hours on 16 and 17 August 2008, a record duration, according to the observing team. Conventional adaptive optics systems using a single Jupiter moon as reference cannot monitor Jupiter for so long because the moon moves too far from the planet. The Hubble Space Telescope cannot observe Jupiter continuously for more than about 50 minutes, because its view is regularly blocked by the Earth during Hubble's 96-minute orbit. Using MAD, ESO astronomer Paola Amico
Jupiter's Rings: Sharpest View
2007-01-01
The New Horizons spacecraft took the best images of Jupiter's charcoal-black rings as it approached and then looked back at Jupiter. The top image was taken on approach, showing three well-defined lanes of gravel- to boulder-sized material composing the bulk of the rings, as well as lesser amounts of material between the rings. New Horizons snapped the lower image after it had passed Jupiter on February 28, 2007, and looked back in a direction toward the sun. The image is sharply focused, though it appears fuzzy due to the cloud of dust-sized particles enveloping the rings. The dust is brightly illuminated in the same way the dust on a dirty windshield lights up when you drive toward a 'low' sun. The narrow rings are confined in their orbits by small 'shepherding' moons.
HUBBLE PROVIDES COMPLETE VIEW OF JUPITER'S AURORAS
2002-01-01
NASA's Hubble Space Telescope has captured a complete view of Jupiter's northern and southern auroras. Images taken in ultraviolet light by the Space Telescope Imaging Spectrograph (STIS) show both auroras, the oval- shaped objects in the inset photos. While the Hubble telescope has obtained images of Jupiter's northern and southern lights since 1990, the new STIS instrument is 10 times more sensitive than earlier cameras. This allows for short exposures, reducing the blurring of the image caused by Jupiter's rotation and providing two to five times higher resolution than earlier cameras. The resolution in these images is sufficient to show the 'curtain' of auroral light extending several hundred miles above Jupiter's limb (edge). Images of Earth's auroral curtains, taken from the space shuttle, have a similar appearance. Jupiter's auroral images are superimposed on a Wide Field and Planetary Camera 2 image of the entire planet. The auroras are brilliant curtains of light in Jupiter's upper atmosphere. Jovian auroral storms, like Earth's, develop when electrically charged particles trapped in the magnetic field surrounding the planet spiral inward at high energies toward the north and south magnetic poles. When these particles hit the upper atmosphere, they excite atoms and molecules there, causing them to glow (the same process acting in street lights). The electrons that strike Earth's atmosphere come from the sun, and the auroral lights remain concentrated above the night sky in response to the 'solar wind,' as Earth rotates underneath. Earth's auroras exhibit storms that extend to lower latitudes in response to solar activity, which can be easily seen from the northern U. S. But Jupiter's auroras are caused by particles spewed out by volcanoes on Io, one of Jupiter's moons. These charged particles are then magnetically trapped and begin to rotate with Jupiter, producing ovals of auroral light centered on Jupiter's magnetic poles in both the day and night skies
Baryon-Baryon Interactions ---Nijmegen Extended-Soft-Core Models---
Rijken, T. A.; Nagels, M. M.; Yamamoto, Y.
We review the Nijmegen extended-soft-core (ESC) models for the baryon-baryon (BB) interactions of the SU(3) flavor-octet of baryons (N, Lambda, Sigma, and Xi). The interactions are basically studied from the meson-exchange point of view, in the spirit of the Yukawa-approach to the nuclear force problem [H. Yukawa, ``On the interaction of Elementary Particles I'', Proceedings of the Physico-Mathematical Society of Japan 17 (1935), 48], using generalized soft-core Yukawa-functions. These interactions are supplemented with (i) multiple-gluon-exchange, and (ii) structural effects due to the quark-core of the baryons. We present in some detail the most recent extended-soft-core model, henceforth referred to as ESC08, which is the most complete, sophisticated, and successful interaction-model. Furthermore, we discuss briefly its predecessor the ESC04-model [Th. A. Rijken and Y. Yamamoto, Phys. Rev. C 73 (2006), 044007; Th. A. Rijken and Y. Yamamoto, Ph ys. Rev. C 73 (2006), 044008; Th. A. Rijken and Y. Yamamoto, nucl-th/0608074]. For the soft-core one-boson-exchange (OBE) models we refer to the literature [Th. A. Rijken, in Proceedings of the International Conference on Few-Body Problems in Nuclear and Particle Physics, Quebec, 1974, ed. R. J. Slobodrian, B. Cuec and R. Ramavataram (Presses Universitè Laval, Quebec, 1975), p. 136; Th. A. Rijken, Ph. D. thesis, University of Nijmegen, 1975; M. M. Nagels, Th. A. Rijken and J. J. de Swart, Phys. Rev. D 17 (1978), 768; P. M. M. Maessen, Th. A. Rijken and J. J. de Swart, Phys. Rev. C 40 (1989), 2226; Th. A. Rijken, V. G. J. Stoks and Y. Yamamoto, Phys. Rev. C 59 (1999), 21; V. G. J. Stoks and Th. A. Rijken, Phys. Rev. C 59 (1999), 3009]. All ingredients of these latter models are also part of ESC08, and so a description of ESC08 comprises all models so far in principle. The extended-soft-core (ESC) interactions consist of local- and non-local-potentials due to (i) one-boson-exchanges (OBE), which are the members of nonets of
Can Terrestrial Planets Form in Hot-Jupiter Systems?
Fogg, Martyn J
2007-01-01
Models of terrestrial planet formation in the presence of a migrating giant planet have challenged the notion that hot-Jupiter systems lack terrestrial planets. We briefly review this issue and suggest that hot-Jupiter systems should be prime targets for future observational missions designed to detect Earth-sized and potentially habitable worlds.
Extended MHD Modeling of Tearing-Driven Magnetic Relaxation
Sauppe, Joshua
2016-10-01
Driven plasma pinch configurations are characterized by the gradual accumulation and episodic release of free energy in discrete relaxation events. The hallmark of this relaxation in a reversed-field pinch (RFP) plasma is flattening of the parallel current density profile effected by a fluctuation-induced dynamo emf in Ohm's law. Nonlinear two-fluid modeling of macroscopic RFP dynamics has shown appreciable coupling of magnetic relaxation and the evolution of plasma flow. Accurate modeling of RFP dynamics requires the Hall effect in Ohm's law as well as first order ion finite Larmor radius (FLR) effects, represented by the Braginskii ion gyroviscous stress tensor. New results find that the Hall dynamo effect from / ne can counter the MHD effect from - in some of the relaxation events. The MHD effect dominates these events and relaxes the current profile toward the Taylor state, but the opposition of the two dynamos generates plasma flow in the direction of equilibrium current density, consistent with experimental measurements. Detailed experimental measurements of the MHD and Hall emf terms are compared to these extended MHD predictions. Tracking the evolution of magnetic energy, helicity, and hybrid helicity during relaxation identifies the most important contributions in single-fluid and two-fluid models. Magnetic helicity is well conserved relative to the magnetic energy during relaxation. The hybrid helicity is dominated by magnetic helicity in realistic low-beta pinch conditions and is also well conserved. Differences of less than 1 % between magnetic helicity and hybrid helicity are observed with two-fluid modeling and result from cross helicity evolution through ion FLR effects, which have not been included in contemporary relaxation theories. The kinetic energy driven by relaxation in the computations is dominated by velocity components perpendicular to the magnetic field, an effect that had not been predicted. Work performed at University of Wisconsin
Low-energy limit of the extended Linear Sigma Model
Divotgey, Florian; Giacosa, Francesco; Rischke, Dirk H
2016-01-01
The extended Linear Sigma Model (eLSM) is an effective hadronic model based on the linear realization of chiral symmetry $SU(N_f)_L \\times SU(N_f)_R$, with (pseudo)scalar and (axial-)vector mesons as degrees of freedom. In this paper, we study the low-energy limit of the eLSM for $N_f=2$ flavors by integrating out all fields except for the pions, the (pseudo-)Nambu--Goldstone bosons of chiral symmetry breaking. We only keep terms entering at tree level and up to fourth order in powers of derivatives of the pion fields. Up to this order, there are four low-energy coupling constants in the resulting low-energy effective action. We show that the latter is formally identical to Chiral Perturbation Theory (ChPT), after choosing a representative for the coset space generated by chiral symmetry breaking and expanding up to fourth order in powers of derivatives of the pion fields. Two of the low-energy coupling constants of the eLSM are uniquely determined by a fit to hadron masses and decay widths. We find that thei...
Strong Langmuir turbulence at Jupiter?
Cairns, Iver H.; Robinson, P. A.
1992-01-01
Langmuir wave packets with short scale lengths less than an approximately equal to 100 lambda e have been observed in Jupiter's foreshock. Theoretical constraints on the electric fields and scale sizes of collapsing wave packets are summarized, extended and placed in a form suitable for easy comparison with Voyager and Ulysses data. The published data are reviewed and possible instrumental underestimation of fields discussed. New upper limits for the fields of the published wave packets are estimated. Wave packets formed at the nucleation scale from the observed large-scale fields cannot collapse because they are disrupted before collapse occurs. The published wave packets are quantitatively inconsistent with strong turbulence collapse. Strict constraints exist for more intense wave packets to be able to collapse: E greater than or approximately equals to 1-8 mV/m for scales less than or approximately equal to 100 lambda e. Means for testing these conclusions using Voyager and Ulysses data are suggested.
Polarons in semiconducting polymers: Study within an extended Holstein model
Meisel, K. D.; Vocks, H.; Bobbert, P. A.
2005-05-01
We present a study of electron- (hole-) phonon interaction and polaron formation in semiconducting polymers within an extended Holstein model. A minimization of the lowest electronic state of this Hamiltonian with respect to lattice degrees of freedom yields the polaronic ground state. Input parameters of this Hamiltonian are obtained from ab initio calculations based on the density-functional theory. We calculate optical phonon modes and the coupling constants of these modes to the highest occupied and lowest unoccupied molecular orbital bands, respectively. For the studied polymers [polythiophene, poly(phenylenevinylene), poly(para-phenylene)] the polaron binding energy, its size, and the lattice deformation as a function of conjugation length have been determined. Self-trapped polarons are found for long conjugation lengths. Energies of prominent PPV modes involved in polaron formation agree with infrared spectra. The polaron binding energies we find are much smaller than the width of the energy disorder in polymeric systems of practical importance, thus self-trapping effects can be ignored in practice.
McDonald, Kim A.
1994-01-01
Collision of a comet with Jupiter beginning July 16, 1994 will be observed by astronomers worldwide, with computerized information relayed to a center at the University of Maryland, financed by the National Aeronautics and Space Administration and National Science Foundation. Geologists and paleontologists also hope to learn more about earth's…
Kipping, David M; Henze, Chris; Teachey, Alex; Isaacson, Howard T; Petigura, Erik A; Marcy, Geoffrey W; Buchhave, Lars A; Chen, Jingjing; Bryson, Steve T; Sandford, Emily
2016-01-01
Decadal-long radial velocity surveys have recently started to discover analogs to the most influential planet of our solar system, Jupiter. Detecting and characterizing these worlds is expected to shape our understanding of our uniqueness in the cosmos. Despite the great successes of recent transit surveys, Jupiter analogs represent a terra incognita, owing to the strong intrinsic bias of this method against long orbital periods. We here report on the first validated transiting Jupiter analog, Kepler-167e (KOI-490.02), discovered using Kepler archival photometry orbiting the K4-dwarf KIC-3239945. With a radius of $(0.91\\pm0.02)$ $R_{\\mathrm{Jup}}$, a low orbital eccentricity ($0.06_{-0.04}^{+0.10}$) and an equilibrium temperature of $(131\\pm3)$ K, Kepler-167e bears many of the basic hallmarks of Jupiter. Kepler-167e is accompanied by three Super-Earths on compact orbits, which we also validate, leaving a large cavity of transiting worlds around the habitable-zone. With two transits and continuous photometric ...
Directory of Open Access Journals (Sweden)
S. W. H. Cowley
2008-12-01
Full Text Available We develop two related models of magnetosphere-ionosphere coupling in the jovian system by combining previous models defined at ionospheric heights with magnetospheric magnetic models that allow system parameters to be extended appropriately into the magnetosphere. The key feature of the combined models is thus that they allow direct connection to be made between observations in the magnetosphere, particularly of the azimuthal field produced by the magnetosphere-ionosphere coupling currents and the plasma angular velocity, and the auroral response in the ionosphere. The two models are intended to reflect typical steady-state sub-corotation conditions in the jovian magnetosphere, and transient super-corotation produced by sudden major solar wind-induced compressions, respectively. The key simplification of the models is that of axi-symmetry of the field, flow, and currents about the magnetic axis, limiting their validity to radial distances within ~30 R_{J} of the planet, though the magnetic axis is appropriately tilted relative to the planetary spin axis and rotates with the planet. The first exploration of the jovian polar magnetosphere is planned to be undertaken in 2016–2017 during the NASA New Frontiers Juno mission, with observations of the polar field, plasma, and UV emissions as a major goal. Evaluation of the models along Juno planning orbits thus produces predictive results that may aid in science mission planning. It is shown in particular that the low-altitude near-periapsis polar passes will generally occur underneath the corresponding auroral acceleration regions, thus allowing brief examination of the auroral primaries over intervals of ~1–3 min for the main oval and ~10 s for narrower polar arc structures, while the "lagging" field deflections produced by the auroral current systems on these passes will be ~0.1°, associated with azimuthal fields above the ionosphere of a few hundred nT.
Radiation-Hydrodynamics of Hot Jupiter Atmospheres
Menou, Kristen
2009-01-01
Radiative transfer in planetary atmospheres is usually treated in the static limit, i.e., neglecting atmospheric motions. We argue that hot Jupiter atmospheres, with possibly fast (sonic) wind speeds, may require a more strongly coupled treatment, formally in the regime of radiation-hydrodynamics. To lowest order in v/c, relativistic Doppler shifts distort line profiles along optical paths with finite wind velocity gradients. This leads to flow-dependent deviations in the effective emission and absorption properties of the atmospheric medium. Evaluating the overall impact of these distortions on the radiative structure of a dynamic atmosphere is non-trivial. We present transmissivity and systematic equivalent width excess calculations which suggest possibly important consequences for radiation transport in hot Jupiter atmospheres. If winds are fast and bulk Doppler shifts are indeed important for the global radiative balance, accurate modeling and reliable data interpretation for hot Jupiter atmospheres may p...
Capture of Irregular Satellites at Jupiter
Nesvorny, D; Deienno, R
2014-01-01
The irregular satellites of outer planets are thought to have been captured from heliocentric orbits. The exact nature of the capture process, however, remains uncertain. We examine the possibility that irregular satellites were captured from the planetesimal disk during the early Solar System instability when encounters between the outer planets occurred (Nesvorny, Vokrouhlicky & Morbidelli 2007, AJ 133; hereafter NVM07). NVM07 already showed that the irregular satellites of Saturn, Uranus and Neptune were plausibly captured during planetary encounters. Here we find that the current instability models present favorable conditions for capture of irregular satellites at Jupiter as well, mainly because Jupiter undergoes a phase of close encounters with an ice giant. We show that the orbital distribution of bodies captured during planetary encounters provides a good match to the observed distribution of irregular satellites at Jupiter. The capture efficiency for each particle in the original transplanetary d...
Radiation belts of jupiter: a second look.
Fillius, R W; McIlwain, C E; Mogro-Campero, A
1975-05-02
The outbound leg of the Pioneer 11 Jupiter flyby explored a region farther from the equator than that traversed by Pioneer 10, and the new data require modification or augmentation of the magnetodisk model based on the Pioneer 10 flyby. The inner moons of Jupiter are sinks of energetic particles and sometimes sources. A large spike of particles was found near lo. Multiple peaks occurred in the particle fluxes near closest approach to the planet; this structure may be accounted for by a complex magnetic field configuration. The decrease in proton flux observed near minimum altitude on the Pioneer 10 flyby appears attributable to particle absorption by Amalthea.
Emergent lattices with geometrical frustration in doped extended Hubbard models
Kaneko, Ryui; Tocchio, Luca F.; Valentí, Roser; Gros, Claudius
2016-11-01
Spontaneous charge ordering occurring in correlated systems may be considered as a possible route to generate effective lattice structures with unconventional couplings. For this purpose we investigate the phase diagram of doped extended Hubbard models on two lattices: (i) the honeycomb lattice with on-site U and nearest-neighbor V Coulomb interactions at 3 /4 filling (n =3 /2 ) and (ii) the triangular lattice with on-site U , nearest-neighbor V , and next-nearest-neighbor V' Coulomb interactions at 3 /8 filling (n =3 /4 ). We consider various approaches including mean-field approximations, perturbation theory, and variational Monte Carlo. For the honeycomb case (i), charge order induces an effective triangular lattice at large values of U /t and V /t , where t is the nearest-neighbor hopping integral. The nearest-neighbor spin exchange interactions on this effective triangular lattice are antiferromagnetic in most of the phase diagram, while they become ferromagnetic when U is much larger than V . At U /t ˜(V/t ) 3 , ferromagnetic and antiferromagnetic exchange interactions nearly cancel out, leading to a system with four-spin ring-exchange interactions. On the other hand, for the triangular case (ii) at large U and finite V', we find no charge order for small V , an effective kagome lattice for intermediate V , and one-dimensional charge order for large V . These results indicate that Coulomb interactions induce [case (i)] or enhance [case(ii)] emergent geometrical frustration of the spin degrees of freedom in the system, by forming charge order.
The Capture of Jupiter Trojans
Morbidelli, A.; Nesvorny, D.; Vokrouhlicky, D.
2013-09-01
The origin of Jupiter Trojans remained mysterious for decades. Particularly, it was difficult to explain the excitation of the inclinations of the Trojan population [1]. In 2005, Morbidelli et al. [2] proposed a scenario of capture from the trans-Neptunian disk, in the framework of the so-called "Nice model" [3,4]. This scenario explained in a natural way the observed orbital distribution of Trojans. The Nice model, however, evolved in the years, in order to satisfy an increasingly large number of constraints. It now appears that the dynamical evolution of the giant planets was different from that envisioned in [2]. Here, we assess again the process of capture of Trojans within this new evolution. We show that (6-8)×10 - 7 of the original trans-Neptunian planetesimals are captured in the Trojan region, with an orbital distribution consistent with the one observed. Relative to [2], the new capture mechanism has the potential of explaining the asymmetry between the L4 and L5 populations. Moreover, the resulting population of Trojans is consistent with that of the Irregular Satellites of Jupiter, which are captured in the same process; a few bodies from the main asteroid belt could also be captured in the Trojan cloud.
Modeling of heavy metal salt solubility using the Extended UNIQUAC model
DEFF Research Database (Denmark)
Iliuta, Maria Cornelia; Thomsen, Kaj; Rasmussen, Peter
2002-01-01
Solid-liquid equilibria in complex aqueous systems involving a heavy metal cation (Mn2+, Fe2+, Co2+, Ni2+, Cu2+, or Zn2+) and one or more ions for which Extended UNIQUAC parameters have been published previously are modeled using the Extended UNIQUAC model. Model parameters are determined...... on the basis of a data bank with more than 4, 000 experimental data points for binary and ternary aqueous systems. The parameters are generally valid in the temperature range from the freezing point to the boiling point of the respective solutions....
Thermodynamic modelling of acid gas removal from natural gas using the Extended UNIQUAC model
DEFF Research Database (Denmark)
Sadegh, Negar; Stenby, Erling Halfdan; Thomsen, Kaj
2017-01-01
Thermodynamics of natural gas sweetening process needs to be known for proper design of natural gas treating plants. Absorption with aqueous N-Methyldiethanolamine is currently the most commonly used process for removal of acid gas (CO2 and H2S) impurities from natural gas. Model parameters...... for the Extended UNIQUAC model have already been determined by the same authors to calculate single acid gas solubility in aqueous MDEA. In this study, the model is further extended to estimate solubility of CO2 and H2S and their mixture in aqueous MDEA at high pressures with methane as a makeup gas....
Orton, Glenn; Hansen, Candice; Momary, Thomas; Caplinger, Michael; Ravine, Michael; Atreya, Sushil; Ingersoll, Andrew; Bolton, Scott; Rogers, John; Eichstaedt, Gerald
2017-04-01
Juno's visible imager, JunoCam, is a wide-angle camera (58° field of view) with 4 color filters: red, green and blue (RGB) and methane at 889 nm, designed for optimal imaging of Jupiter's poles. Juno's elliptical polar orbit offers unique views of Jupiter's polar regions with spatial scales as good as 50 km/pixel. At closest approach ("perijove") the images have spatial scale down to ˜3 km/pixel. As a push-frame imager on a rotating spacecraft, JunoCam uses time-delayed integration to take advantage of the spacecraft spin to extend integration time to increase signal. Images of Jupiter's poles reveal a largely uncharted region of Jupiter, as nearly all earlier spacecraft except Pioneer 11 have orbited or flown by close to the equatorial plane. Poleward of 64-68° planetocentric latitude, Jupiter's familiar east-west banded structure breaks down. Several types of discrete features appear on a darker, bluish-cast background. Clusters of circular cyclonic spirals are found immediately around the north and south poles. Oval-shaped features are also present, ranging in size down to JunoCam's resolution limits. The largest and brightest features usually have chaotic shapes; animations over ˜1 hour can reveal cyclonic motion in them. Narrow linear features traverse tens of degrees of longitude and are not confined in latitude. JunoCam also detected optically thin clouds or hazes that are illuminated beyond the nightside ˜1-bar terminator; one of these detected at Perijove lay some 3 scale heights above the main cloud deck. Tests have been made to detect the aurora and lightning. Most close-up images of Jupiter have been acquired at lower latitudes within 2 hours of closest approach. These images aid in understanding the data collected by other instruments on Juno that probe deeper in the atmosphere. When Jupiter was too close to the sun for ground-based observers to collect data between perijoves 1 and 2, JunoCam took a sequence of routine images to monitor large
2001-01-01
These images taken through the wide angle camera near closest approach in the deep near-infrared methane band, combined with filters which sense electromagnetic radiation of orthogonal polarization, show that the light from the poles is polarized. That is, the poles appear bright in one image, and dark in the other. Polarized light is most readily scattered by aerosols. These images indicate that the aerosol particles at Jupiter's poles are small and likely consist of aggregates of even smaller particles, whereas the particles at the equator and covering the Great Red Spot are larger. Images like these will allow scientists to ascertain the distribution, size and shape of aerosols, and consequently, the distribution of heat, in Jupiter's atmosphere.
Pappalardo, R. T.
2004-01-01
When the twin Voyager spacecraft cruised past Jupiter in 1979, they did more than rewrite the textbooks on the giant planet. Their cameras also unveiled the astounding diversity of the four planet-size moons of ice and stone known as the Galilean satellites. The Voyagers revealed the cratered countenance of Callisto, the valleys and ridges of Ganymede, the cracked face of Europa, and the spewing volcanoes of Io. But it would take a spacecraft named for Italian scientist Galileo, who discovered the moons in 1610, to reveal the true complexity of these worlds and to begin to divulge their interior secrets. Incredibly, the Galileo data strongly suggest that Jupiter's three large icy moons (all but rocky Io) hide interior oceans.
Atmospheric Escape from Hot Jupiters
Murray-Clay, Ruth; Murray, Norman
2008-01-01
Photoionization heating from UV radiation incident on the atmospheres of hot Jupiters may drive planetary mass loss. We construct a model of escape that includes realistic heating and cooling, ionization balance, tidal gravity, and pressure confinement by the host star wind. We show that mass loss takes the form of a hydrodynamic ("Parker") wind, emitted from the planet's dayside during lulls in the stellar wind. When dayside winds are suppressed by the confining action of the stellar wind, nightside winds might pick up if there is sufficient horizontal transport of heat. A hot Jupiter loses mass at maximum rates of ~2 x 10^12 g/s during its host star's pre-main-sequence phase and ~2 x10^10 g/s during the star's main sequence lifetime, for total maximum losses of ~0.06% and ~0.6% of the planet's mass, respectively. For UV fluxes F_UV < 10^4 erg/cm^2/s, the mass loss rate is approximately energy-limited and is proportional to F_UV^0.9. For larger UV fluxes, such as those typical of T Tauri stars, radiative ...
Batygin, Konstantin
2017-06-01
The statistics of extrasolar planetary systems indicate that the default mode of planetary formation generates planets with orbital periods shorter than 100 days, and masses substantially exceeding that of the Earth. When viewed in this context, the Solar System, which contains no planets interior to Mercury's 88-day orbit, is unusual. Extra-solar planetary detection surveys also suggest that planets with masses and periods broadly similar to Jupiter's are somewhat uncommon, with occurrence fraction of less than ~ 10%. In this talk, I will present calculations which show that a popular formation scenario for Jupiter and Saturn, in which Jupiter migrates inward from a > 5AU to a ˜ 1.5 AU and then reverses direction, can explain the low overall mass of the Solar System's terrestrial planets, as well as the absence of planets with a 10 - 100 km planetesimals into low- order mean-motion resonances, shepherding of order 10 Earth masses of this material into the a ˜ 1 AU region while exciting substantial orbital eccentricity (e ˜ 0.2 - 0.4). We argue that under these conditions, a collisional cascade will ensue, generating a planetesimal disk that would have flushed any preexisting short-period super-Earth-like planets into the Sun. In this scenario, the Solar System's terrestrial planets formed from gas-starved mass-depleted debris that remained after the primary period of dynamical evolution.
1998-01-01
NASA's Voyager 1 took this picture of the planet Jupiter on Saturday, Jan. 6, the first in its three-month-long, close-up investigation of the largest planet. The spacecraft, flying toward a March 5 closest approach, was 35.8 million miles (57.6 million kilometers) from Jupiter and 371.7 million miles (598.2 million kilometers) from Earth when the picture was taken. As the Voyager cameras begin their meteorological surveillance of Jupiter, they reveal a dynamic atmosphere with more convective structure than had previously been thought. While the smallest atmospheric features seen in this picture are still as large as 600 miles (1,000 kilometers) across, Voyager will be able to detect individual storm systems as small as 3 miles (5 kilometers) at closest approach. The Great Red Spot can be seen near the limb at the far right. Most of the other features are too small to be seen in terrestrial telescopes. This picture was transmitted to the Jet Propulsion Laboratory through the Deep Space Network's tracking station at Madrid, Spain. The Voyager Project is managed for NASA by Caltech's Jet Propulsion Laboratory.
Atreya, S. K.
Whereas in-situ measurements of the composition of Jupiter by the Galileo probe have resulted in the determination of the elemental abundances of C N S Ne Ar Kr Xe Noble gas isotopes D H 3He 4He and 14N 15N in the well-mixed atmosphere 1 2 the GCMS measurements on the Hyugens probe 3 have shed light on the chemical species that are produced in the stratosphere but condense in the troposphere and the surface of Titan In both cases such measurements are key to understanding the formation of these bodies and the origin of their atmsospheres In this talk I will discuss the composition stratospheric chemistry and tropospheric condensation processes in the giant planets and Titan drawing parallels where they exist and contrasting where they don t The important role of transport to and from the interior for recycling key photochemical species on the giant planets and of photochemical loss of methane in the stratopshere and its geologic production in the interior will also be discussed References 1 Atreya S K paper in Session C3 1 2 Atreya S K Wong A S in Outer Planets T Encrenaz et al eds Springer-Verlag pp 121-136 2005 3 Niemann H B and the Cassini-Huygens GCMS Team Nature 438 779 2005
Voyager 2 Jupiter Eruption Movie
2000-01-01
This movie records an eruptive event in the southern hemisphere of Jupiter over a period of 8 Jupiter days. Prior to the event, an undistinguished oval cloud mass cruised through the turbulent atmosphere. The eruption occurs over avery short time at the very center of the cloud. The white eruptive material is swirled about by the internal wind patterns of the cloud. As a result of the eruption, the cloud then becomes a type of feature seen elsewhere on Jupiter known as 'spaghetti bowls'.As Voyager 2 approached Jupiter in 1979, it took images of the planet at regular intervals. This sequence is made from 8 images taken once every Jupiter rotation period (about 10 hours). These images were acquired in the Violet filter around May 6, 1979. The spacecraft was about 50 million kilometers from Jupiter at that time.This time-lapse movie was produced at JPL by the Image Processing Laboratory in 1979.
DEFF Research Database (Denmark)
Jørgensen, Peter Løchte
Extended Nelson-Siegel models are widely used by e.g. practitioners and central banks to estimate current term structures of riskless zero-coupon interest rates, whereas other models such as the extended Vasicek model (a.k.a. the Hull-White model) are popular for pricing interest rate derivatives....... This paper establishes theoretical consistency between these two types of models by showing how to specify the extended Vasicek model such that its implied initial term structure curve precisely matches a given extended Nelson-Siegel specification. That is, we show how to reconcile the two classes of models...
An Overview of the Jupiter Europa Orbiter Concept's Europa Science Phase Orbit Design
Lock, Robert E.; Ludwinski, Jan M.; Petropoulos, Anastassios E.; Clark, Karla B.; Pappalardo, Robert T.
2009-01-01
Jupiter Europa Orbiter (JEO), the proposed NASA element of the proposed joint NASA-ESA Europa Jupiter System Mission (EJSM), could launch in February 2020 and conceivably arrive at Jupiter in December of 2025. The concept is to perform a multi-year study of Europa and the Jupiter system, including 30 months of Jupiter system science and a comprehensive Europa orbit phase of 9 months. This paper provides an overview of the JEO concept and describes the Europa Science phase orbit design and the related science priorities, model pay-load and operations scenarios needed to conduct the Europa Science phase. This overview is for planning and discussion purposes only.
Jupiter small satellite montage
2000-01-01
A montage of images of the small inner moons of Jupiter from the camera onboard NASA's Galileo spacecraft shows the best views obtained of these moons during Galileo's 11th orbit around the giant planet in November 1997. At that point, Galileo was completing its first two years in Jupiter orbit--known as the Galileo 'prime mission'--and was about to embark on a successful two-year extension, called the Galileo Europa Mission. The top two images show the moon Thebe. Thebe rotates by approximately 50 degrees between the time these two images were taken, so that the same prominent impact crater is seen in both views; this crater, which has been given the provisional name Zethus, is near the point on Thebe that faces permanently away from Jupiter. The next two images show the moon Amalthea; they were taken with the Sun directly behind the observer, an alignment that emphasizes patterns of intrinsically bright or dark surface material. The third image from the top is a view of Amalthea's leading side, the side of the moon that 'leads' as Amalthea moves in its orbit around Jupiter. This image looks 'noisy' because it was obtained serendipitously during an observation of the Jovian satellite Io (Amalthea and Io shared the same camera frame but the image was exposed for bright Io rather than for the much darker Amalthea). The fourth image from the top emphasizes prominent 'spots' of relatively bright material that are located near the point on Amalthea that faces permanently away from Jupiter. The bottom image is a view of the tiny moon Metis. In all the images, north is approximately up, and the moons are shown in their correct relative sizes. The images are, from top to bottom: Thebe taken on November 7, 1997 at a range of 504,000 kilometers (about 313,000 miles); Thebe on November 7, 1997 at a range of 548,000 kilometers (about 340,000 miles); Amalthea on November 6, 1997 at a range of about 650,000 kilometers (about 404,000 miles); Amalthea on November 7, 1997 at a
2007-01-01
This 'movie' strings 11 images of Jupiter captured by the New Horizons Long Range Reconnaissance Imager (LORRI) on January 9, 2007, when the spacecraft was about 80 million kilometers (49.6 million miles) from the giant planet. The sequence covers a full 10-hour rotation of Jupiter, during which the moons Ganymede and Io -- as well as the shadows they cast on Jupiter -- move across the camera's field of view.
de Pater, Imke
1981-05-01
On the basis of comparison of radio data and model calculations of Jupiter's synchrotron radiaton the 'hot region' or east-west asymmetry in the planet's radiation belts is proposed to be due to the combined effect of an overabundance of electrons at jovicentric longitudes λJ~240°-360° and the existence of a dusk dawn directed electric field over the inner magnetosphere, generated by the wind system in the upper atmosphere. The model calculations were based upon the magnetic field configurations derived from the Pioneer data by Acuna and Ness [1976] (the O4 model) and Davis, Jones and Smith (quoted in Smith and Gulkis [1979]) (the P11 (3,2)A model), with an electron distribution derived in the first paper of this series [de Pater, this issue]. We would infer from the calculations that the O4 model gives a slightly better fit to the data; the relatively large number density at λJ~240°-360°, however, might indicate the presence of even higher order moments in the field.
Limits to Determining the Core of Jupiter
Stevenson, David J.
2016-10-01
Simple, approximate models based on perturbations of the n=1 polytrope are used to identify some general properties of models for nearly-isentropic Jupiter-like planets where the total heavy element mass fraction is small. In these models, it is found that the radius is remarkably insensitive to the distribution of heavy elements and is effectively a measure of total heavy element enrichment (sum of core and envelope). The gravity harmonic J2 and the normalized moment of inertia α=I/MR2 are almost entirely determined by the density structure outside the core, and this depends on the reduced core mass, defined to be the actual core mass minus the mass of hydrogen and helium that would occupy that region in the absence of the core. The actual core mass or its radius or composition cannot be well determined, even when there is perfect knowledge of the equation of state, thermal state and envelope enrichment by heavy elements. The central concentration of heavy elements is approximately determined, even when the actual core is more massive and contaminated with hydrogen and helium by mixing or erosion (double diffusive convection). At fixed J2, the dependence of α on core structure is very small, and only exceeds the likely detection limit ~0.1-0.2% for very extended cores. Even though these results are obtained for a simple model, it is argued that they are semi-quantitatively applicable to realistic models. A perturbation scheme is presented for testing this systematically and for assessing the consequences of perturbations to the equation of state, compositional profile and temperature structure for the trade-off between reduced core mass and envelope enrichment.
Baines, Kevin; Sromovsky, Lawrence A.; Fry, Patrick M.; Carlson, Robert W.; Momary, Thomas W.
2016-10-01
We report results incorporating the red-tinted photochemically-generated aerosols of Carlson et al (2016, Icarus 274, 106-115) in spectral models of Jupiter's Great Red Spot (GRS). Spectral models of the 0.35-1.0-micron spectrum show good agreement with Cassini/VIMS near-center-meridian and near-limb GRS spectra for model morphologies incorporating an optically-thin layer of Carlson (2016) aerosols at high altitudes, either at the top of the tropospheric GRS cloud, or in a distinct stratospheric haze layer. Specifically, a two-layer "crème brûlée" structure of the Mie-scattering Carlson et al (2016) chromophore attached to the top of a conservatively scattering (hereafter, "white") optically-thick cloud fits the spectra well. Currently, best agreement (reduced χ2 of 0.89 for the central-meridian spectrum) is found for a 0.195-0.217-bar, 0.19 ± 0.02 opacity layer of chromophores with mean particle radius of 0.14 ± 0.01 micron. As well, a structure with a detached stratospheric chromophore layer ~0.25 bar above a white tropospheric GRS cloud provides a good spectral match (reduced χ2 of 1.16). Alternatively, a cloud morphology with the chromophore coating white particles in a single optically- and physically-thick cloud (the "coated-shell model", initially explored by Carlson et al 2016) was found to give significantly inferior fits (best reduced χ2 of 2.9). Overall, we find that models accurately fit the GRS spectrum if (1) most of the optical depth of the chromophore is in a layer near the top of the main cloud or in a distinct separated layer above it, but is not uniformly distributed within the main cloud, (2) the chromophore consists of relatively small, 0.1-0.2-micron-radius particles, and (3) the chromophore layer optical depth is small, ~ 0.1-0.2. Thus, our analysis supports the exogenic origin of the red chromophore consistent with the Carlson et al (2016) photolytic production mechanism rather than an endogenic origin, such as upwelling of material
Directory of Open Access Journals (Sweden)
Robert Wilkes Ebert
2014-09-01
Full Text Available We examine Ulysses solar wind and interplanetary magnetic field (IMF observations at 5 AU for two ~13 month intervals during the rising and declining phases of solar cycle 23 and the predicted response of the Jovian magnetosphere during these times. The declining phase solar wind, composed primarily of corotating interaction regions and high-speed streams, was, on average, faster, hotter, less dense, and more Alfvénic relative to the rising phase solar wind, composed mainly of slow wind and interplanetary coronal mass ejections. Interestingly, none of solar wind and IMF distributions reported here were bimodal, a feature used to explain the bimodal distribution of bow shock and magnetopause standoff distances observed at Jupiter. Instead, many of these distributions had extended, non-Gaussian tails that resulted in large standard deviations and much larger mean over median values. The distribution of predicted Jupiter bow shock and magnetopause standoff distances during these intervals were also not bimodal, the mean/median values being larger during the declining phase by ~1 – 4%. These results provide data-derived solar wind and IMF boundary conditions at 5 AU for models aimed at studying solar wind-magnetosphere interactions at Jupiter and can support the science investigations of upcoming Jupiter system missions. Here, we provide expectations for Juno, which is scheduled to arrive at Jupiter in July 2016. Accounting for the long-term decline in solar wind dynamic pressure reported by McComas et al. (2013, Jupiter’s bow shock and magnetopause is expected to be at least 8 – 12% further from Jupiter, if these trends continue.
JUPITER PROJECT - JOINT UNIVERSAL PARAMETER IDENTIFICATION AND EVALUATION OF RELIABILITY
The JUPITER (Joint Universal Parameter IdenTification and Evaluation of Reliability) project builds on the technology of two widely used codes for sensitivity analysis, data assessment, calibration, and uncertainty analysis of environmental models: PEST and UCODE.
Pioneer Jupiter orbiter probe mission 1980, probe description
Defrees, R. E.
1974-01-01
The adaptation of the Saturn-Uranus Atmospheric Entry Probe (SUAEP) to a Jupiter entry probe is summarized. This report is extracted from a comprehensive study of Jovian missions, atmospheric model definitions and probe subsystem alternatives.
Fitting Orbits to Jupiter's Moons with a Spreadsheet.
Bridges, Richard
1995-01-01
Describes how a spreadsheet is used to fit a circular orbit model to observations of Jupiter's moons made with a small telescope. Kepler's Third Law and the inverse square law of gravity are observed. (AIM)
The Origin of Retrograde Hot Jupiters
Naoz, Smadar; Farr, W.; Lithwick, Y.; Rasio, F.; Teyssandier, J.
2011-09-01
The search for extra-solar planets has led to the surprising discovery of many Jupiter-like planets in very close proximity to their host star, the so-called ``hot Jupiters'' (HJ). Even more surprisingly, many of these HJs have orbits that are eccentric or highly inclined with respect to the equator of the star, and some (about 25%) even orbiting counter to the spin direction of the star. This poses a unique challenge to all planet formation models. We show that secular interactions between Jupiter-like planet and another perturber in the system can easily produce retrograde HJ orbits. We show that in the frame of work of secular hierarchical triple system (the so-called Kozai mechanism) the inner orbit's angular momentum component parallel to the total angular momentum (i.e., the z-component of the inner orbit angular momentum) need not be constant. In fact, it can even change sign, leading to a retrograde orbit. A brief excursion to very high eccentricity during the chaotic evolution of the inner orbit allows planet-star tidal interactions to rapidly circularize that orbit, decoupling the planets and forming a retrograde hot Jupiter. We estimate the relative frequencies of retrograde orbits and counter to the stellar spin orbits using Monte Carlo simulations, and find that the they are consistent with the observations. The high observed incidence of planets orbiting counter to the stellar spin direction may suggest that planet--planet secular interactions are an important part of their dynamical history.
Extending the Compensatory Model of Second Language Reading
McNeil, Levi
2012-01-01
Bernhardt (2005) proposed a compensatory model of second language reading. This model predicted that 50% of second language (L2) reading scores are attributed to second language knowledge and first-language (L1) reading ability. In this model, these two factors compensate for deficiencies in each other. Although this model explains a significant…
Roberts, M S; Anissimov, Y G
1999-08-01
The conventional convection-dispersion (also called axial dispersion) model is widely used to interrelate hepatic availability (F) and clearance (Cl) with the morphology and physiology of the liver and to predict effects such as changes in liver blood flow on F and Cl. An extended form of the convection-dispersion model has been developed to adequately describe the outflow concentration-time profiles for vascular markers at both short and long times after bolus injections into perfused livers. The model, based on flux concentration and a convolution of catheters and large vessels, assumes that solute elimination in hepatocytes follows either fast distribution into or radial diffusion in hepatocytes. The model includes a secondary vascular compartment, postulated to be interconnecting sinusoids. Analysis of the mean hepatic transit time (MTT) and normalized variance (CV2) of solutes with extraction showed that the discrepancy between the predictions of MTT and CV2 for the extended and unweighted conventional convection-dispersion models decreases as hepatic extraction increases. A correspondence of more than 95% in F and Cl exists for all solute extractions. In addition, the analysis showed that the outflow concentration-time profiles for both the extended and conventional models are essentially identical irrespective of the magnitude of rate constants representing permeability, volume, and clearance parameters, providing that there is significant hepatic extraction. In conclusion, the application of a newly developed extended convection-dispersion model has shown that the unweighted conventional convection-dispersion model can be used to describe the disposition of extracted solutes and, in particular, to estimate hepatic availability and clearance in both experimental and clinical situations.
Practice models and roles of physician extenders in dermatologic surgery.
Tierney, Emily P; Hanke, C William; Kimball, Alexa Boer
2011-05-01
The prevalence of physician extenders (PEs) has increased significantly in dermatologic surgery over the last decade. An analysis was performed of the staff in dermatologic surgery practices, roles of PEs, and level of supervision. Mohs fellowship-trained (MMSFT) dermatologic surgeons were more likely to employ registered nurses (n=85, 73.9%) than non-fellowship-trained (NMMSFT) surgeons (n=65, 50.0%, pdermatology patients, but NMMSFT surgeons were twice as likely as MMSFT surgeons to have their PEs involved in performing or assisting with cosmetic procedures. MMSFT surgeons (38.5%) were twice as likely to have direct supervision of their PEs as NMMSFT surgeons (16.1%, p=.01). PEs are highly prevalent in dermatologic surgery practices and are playing direct roles in the delivery of dermatologic care. Promoting patient safety through appropriate extender supervision and reporting of patient outcomes are highly needed as this sector of the dermatologic surgery workforce continues to expand. © 2011 by the American Society for Dermatologic Surgery, Inc.
Jupiter's Phase Variations from Cassini: a testbed for future direct-imaging missions
Mayorga, Laura; Jackiewicz, Jason; Rages, Kathy; West, Robert; Knowles, Ben; Marley, Mark; Lewis, Nikole
2016-10-01
Phase curves are important for our understanding of the energy balance and scattering behavior of an exoplanet's atmosphere. In preparation for future direct-imaging missions of Jupiter-like planets, we present phase curves of Jupiter from 0--150 degrees as measured in multiple optical bandpasses by Cassini/ISS during the Millennium flyby of Jupiter in late 2000 to early 2001. We demonstrate and confirm that Jupiter is not well represented by a Lambertian phase function and that its color is more variable with phase angle than predicted by Jupiter-like models. This indicates that a Jupiter-twin observed near quadrature may not be as straightforward to classify as a Jupiter-like planet.
Jupiter's Phase Variations from Cassini: a testbed for future direct-imaging missions
Mayorga, Laura; Jackiewicz, Jason; Rages, Kathy; West, Robert A.; Knowles, Ben; Lewis, Nikole K.; Marley, Mark S.
2017-01-01
Phase curves are important for our understanding of the energy balance and scattering behavior of an exoplanet's atmosphere. In preparation for future direct-imaging missions of Jupiter-like planets, in particular WFIRST, we present phase curves of Jupiter from 0--150 degrees as measured in multiple optical bandpasses by Cassini/ISS during the Millennium flyby of Jupiter in late 2000 to early 2001. We demonstrate and confirm that Jupiter is not well represented by a Lambertian phase function and that its color is more variable with phase angle than predicted by Jupiter-like models. This indicates that a Jupiter-twin observed near quadrature may not be as straightforward to classify as a Jupiter-like planet and comment on the implications for future missions.
Modelling and analysis of Markov reward automata (extended version)
Guck, Dennis; Timmer, Mark; Hatefi, Hassan; Ruijters, Enno; Stoelinga, Mariëlle
2014-01-01
Costs and rewards are important ingredients for cyberphysical systems, modelling critical aspects like energy consumption, task completion, repair costs, and memory usage. This paper introduces Markov reward automata, an extension of Markov automata that allows the modelling of systems incorporating
Cameron, Lindsey; Rutland, Adam; Brown, Rupert; Douch, Rebecca
2006-01-01
The present research evaluated an intervention, derived from the "extended contact hypothesis," which aimed to change children's intergroup attitudes toward refugees. The study (n=253) tested 3 models of extended contact among 5- to 11-year-old children: dual identity, common ingroup identity, and decategorization. Children read friendship stories based upon these models featuring in- and outgroup members. Outgroup attitudes were significantly more positive in the extended contact conditions,...
Muon anomalous magnetic moment in string inspired extended family models
Kephart, T W
2002-01-01
We propose a standard model minimal extension with two lepton weak SU(2) doublets and a scalar singlet to explain the deviation of the measured anomalous magnetic moment of the muon from the standard model expectation. This scheme can be naturally motivated in string inspired models such as E_6 and AdS/CFT.
Extending enterprise architecture modelling with business goals and requirements
Engelsman, Wilco; Quartel, Dick; Jonkers, Henk; Sinderen, van Marten
2011-01-01
The methods for enterprise architecture (EA), such as The Open Group Architecture Framework, acknowledge the importance of requirements modelling in the development of EAs. Modelling support is needed to specify, document, communicate and reason about goals and requirements. The current modelling te
An extended dual search space model of scientific discovery learning
Joolingen, van Wouter R.; Jong, de Ton
1997-01-01
This article describes a theory of scientific discovery learning which is an extension of Klahr and Dunbar''s model of Scientific Discovery as Dual Search (SDDS) model. We present a model capable of describing and understanding scientific discovery learning in complex domains in terms of the SDDS fr
Faraway, Julian J
2005-01-01
Linear models are central to the practice of statistics and form the foundation of a vast range of statistical methodologies. Julian J. Faraway''s critically acclaimed Linear Models with R examined regression and analysis of variance, demonstrated the different methods available, and showed in which situations each one applies. Following in those footsteps, Extending the Linear Model with R surveys the techniques that grow from the regression model, presenting three extensions to that framework: generalized linear models (GLMs), mixed effect models, and nonparametric regression models. The author''s treatment is thoroughly modern and covers topics that include GLM diagnostics, generalized linear mixed models, trees, and even the use of neural networks in statistics. To demonstrate the interplay of theory and practice, throughout the book the author weaves the use of the R software environment to analyze the data of real examples, providing all of the R commands necessary to reproduce the analyses. All of the ...
Kaufmann, William
1984-01-01
Presents a chapter from an introductory college-level astronomy textbook in which full-color photographs and numerous diagrams highlight an extensive description of the planet Jupiter. Topics include Jupiter's geology, rotation, magnetic field, atmosphere (including clouds and winds), and the Great Red Spot. (DH)
A cosmological dust model with extended f({chi}) gravity
Energy Technology Data Exchange (ETDEWEB)
Carranza, D.A.; Mendoza, S.; Torres, L.A. [Universidad Nacional Autonoma de Mexico, Instituto de Astronomia, AP 70-264, Distrito Federal (Mexico)
2013-01-15
Introducing a fundamental constant of nature with dimensions of acceleration into the theory of gravity makes it possible to extend gravity in a very consistent manner. At the non-relativistic level a MOND-like theory with a modification in the force sector is obtained, which is the limit of a very general metric relativistic theory of gravity. Since the mass and length scales involved in the dynamics of the whole universe require small accelerations of the order of Milgrom's acceleration constant a{sub 0}, it turns out that the relativistic theory of gravity can be used to explain the expansion of the universe. In this work it is explained how to use that relativistic theory of gravity in such a way that the overall large-scale dynamics of the universe can be treated in a pure metric approach without the need to introduce dark matter and/or dark energy components. (orig.)
Extending enterprise architecture modelling with business goals and requirements
Engelsman, Wilco; Quartel, Dick; Jonkers, Henk; van Sinderen, Marten
2011-02-01
The methods for enterprise architecture (EA), such as The Open Group Architecture Framework, acknowledge the importance of requirements modelling in the development of EAs. Modelling support is needed to specify, document, communicate and reason about goals and requirements. The current modelling techniques for EA focus on the products, services, processes and applications of an enterprise. In addition, techniques may be provided to describe structured requirements lists and use cases. Little support is available however for modelling the underlying motivation of EAs in terms of stakeholder concerns and the high-level goals that address these concerns. This article describes a language that supports the modelling of this motivation. The definition of the language is based on existing work on high-level goal and requirements modelling and is aligned with an existing standard for enterprise modelling: the ArchiMate language. Furthermore, the article illustrates how EA can benefit from analysis techniques from the requirements engineering domain.
Faculty's Acceptance of Computer Based Technology: Cross-Validation of an Extended Model
Ahmad, Tunku Badariah Tunku; Madarsha, Kamal Basha; Zainuddin, Ahmad Marzuki; Ismail, Nik Ahmad Hisham; Nordin, Mohamad Sahari
2010-01-01
The first aim of the present study is to validate an extended technology acceptance model (TAME) on the data derived from the faculty members of a university in an ongoing, computer mediated work setting. The study extended the original TAM model by including an intrinsic motivation component--computer self efficacy. In so doing, the study…
Extending the generalized Chaplygin gas model by using geometrothermodynamics
Aviles, Alejandro; Campuzano, Lorena; Quevedo, Hernando
2012-01-01
We use the formalism of geometrothermodynamics (GTD) to derive fundamental thermodynamic equations that are used to construct general relativistic cosmological models. In particular, we show that the simplest possible fundamental equation, which corresponds in GTD to a system with no internal thermodynamic interaction, describes the different fluids of the standard model of cosmology. In addition, a particular fundamental equation with internal thermodynamic interaction is shown to generate a new cosmological model that correctly describes the dark sector of the Universe and contains as a special case the generalized Chaplygin gas model.
How does stellar irradiation make hot Jupiters puffy?
Wei, Yu-Jie; Gu, Pin-Gao
2017-06-01
Hot Jupiters appear to be re-inflated as their host stars evolve and become more luminous, shedding more light on the intriguing correlation between stellar irradiation and the size of hot Jupiters. To account for the phenomenon, one of the well-known models is the thermal-tide scenario proposed by Arras and Socrates. We present a linear analysis of semi-diurnal thermal tides in a hot Jupiter. The Coriolis effect is added to our equation, which generates more wave modes than non-rotating models, such as Rossby, Yanai, and inertial waves. We attempt to investigate where and which mode contributes most of the torque that maintains the planet in an asynchronous state against gravitational tides, leading to re-inflation of a hot Jupiter.
Efficient Modelling and Generation of Markov Automata (extended version)
Timmer, Mark; Katoen, Joost-Pieter; Pol, van de Jaco; Stoelinga, Mariëlle
2012-01-01
This paper introduces a framework for the efficient modelling and generation of Markov automata. It consists of (1) the data-rich process-algebraic language MAPA, allowing concise modelling of systems with nondeterminism, probability and Markovian timing; (2) a restricted form of the language, the M
Hyperstate matrix models : extending demographic state spaces to higher dimensions
Roth, G.; Caswell, H.
2016-01-01
1. Demographic models describe population dynamics in terms of the movement of individuals among states (e.g. size, age, developmental stage, parity, frailty, physiological condition). Matrix population models originally classified individuals by a single characteristic. This was enlarged to two cha
Hazard identification by extended multilevel flow modelling with function roles
DEFF Research Database (Denmark)
Wu, Jing; Zhang, Laibin; Jørgensen, Sten Bay
2014-01-01
HAZOP studies are widely accepted in chemical and petroleum industries as the method for conducting process hazard analysis related to design, maintenance and operation of th e systems. In this paper, a HAZOP reasoning method based on function-oriented modelling, multilevel flow modelling (MFM) i...
Extended master equation models for molecular communication networks
Chou, Chun Tung
2012-01-01
We consider molecular communication networks consisting of transmitters and receivers distributed in a fluidic medium. In such networks, a transmitter sends one or more signalling molecules, which are diffused over the medium, to the receiver to realise the communication. In order to be able to engineer synthetic molecular communication networks, mathematical models for these networks are required. This paper proposes a new stochastic model for molecular communication networks called reaction-diffusion master equation with exogenous input (RDMEX). The key idea behind RDMEX is to model the transmitters as time sequences specify the emission patterns of signalling molecules, while diffusion in the medium and chemical reactions at the receivers are modelled as Markov processes using master equation. An advantage of RDMEX is that it can readily be used to model molecular communication networks with multiple transmitters and receivers. For the case where the reaction kinetics at the receivers is linear, we show ho...
Warm Jupiters are less lonely than hot Jupiters: close neighbours
Huang, Chelsea X; Triaud, Amaury H M J
2016-01-01
Exploiting the Kepler transit data, we uncover a dramatic distinction in the prevalence of sub-Jovian companions, between systems that contain hot Jupiters (periods inward of 10 days) and those that host warm Jupiters (periods between 10 and 200 days). Hot Jupiters as a whole, with the singular exception of WASP-47b, do not have any detectable inner or outer planetary companions (with periods inward of 50 days and sizes down to $2 R_{\\rm Earth}$). Restricting ourselves to inner companions, our limits reach down to $1 R_{\\rm Earth}$. In stark contrast, half of the warm Jupiters are closely flanked by small companions. Statistically, the companion fractions for hot and warm Jupiters are mutually exclusive, in particular in regard to inner companions. The high companion fraction of warm Jupiters also yields clue to their formation. The warm Jupiters that have close-by siblings should have low orbital eccentricities and low mutual inclinations. The orbital configurations of these systems are reminiscent of those ...
DEFF Research Database (Denmark)
Faramarzi, Leila; Kontogeorgis, Georgios; Thomsen, Kaj
2009-01-01
The extended UNIQUAC model [K. Thomsen, R Rasmussen, Chem. Eng. Sci. 54 (1999) 1787-1802] was applied to the thermodynamic representation of carbon dioxide absorption in aqueous monoethanolamine (MEA), methyldiethanolamine (MDEA) and varied strength mixtures of the two alkanolamines (MEA-MDEA). F......The extended UNIQUAC model [K. Thomsen, R Rasmussen, Chem. Eng. Sci. 54 (1999) 1787-1802] was applied to the thermodynamic representation of carbon dioxide absorption in aqueous monoethanolamine (MEA), methyldiethanolamine (MDEA) and varied strength mixtures of the two alkanolamines (MEA......) are included in the parameter estimation process. The previously unavailable standard state properties of the alkanolamine ions appearing in this work, i.e. MEA protonate, MEA carbamate and MDEA protonate are determined. The concentration of the species in both MEA and MDEA solutions containing CO2...
Extended master equation models for molecular communication networks.
Chou, Chun Tung
2013-06-01
We consider molecular communication networks consisting of transmitters and receivers distributed in a fluidic medium. In such networks, a transmitter sends one or more signaling molecules, which are diffused over the medium, to the receiver to realize the communication. In order to be able to engineer synthetic molecular communication networks, mathematical models for these networks are required. This paper proposes a new stochastic model for molecular communication networks called reaction-diffusion master equation with exogenous input (RDMEX). The key idea behind RDMEX is to model the transmitters as time series of signaling molecule counts, while diffusion in the medium and chemical reactions at the receivers are modeled as Markov processes using master equation. An advantage of RDMEX is that it can readily be used to model molecular communication networks with multiple transmitters and receivers. For the case where the reaction kinetics at the receivers is linear, we show how RDMEX can be used to determine the mean and covariance of the receiver output signals, and derive closed-form expressions for the mean receiver output signal of the RDMEX model. These closed-form expressions reveal that the output signal of a receiver can be affected by the presence of other receivers. Numerical examples are provided to demonstrate the properties of the model.
Extending the Modelling Framework for Gas-Particle Systems
DEFF Research Database (Denmark)
Rosendahl, Lasse Aistrup
, with very good results. Single particle combustion has been tested using a number of different particle combustion models applied to coal and straw particles. Comparing the results of these calculations to measurements on straw burnout, the results indicate that for straw, existing heterogeneous combustion...... models perform well, and may be used in high temperature ranges. Finally, the particle tracking and combustion model is applied to an existing coal and straw co- fuelled burner. The results indicate that again, the straw follows very different trajectories than the coal particles, and also that burnout...
Internet enabled modelling of extended manufacturing enterprises using the process based techniques
Cheng, K; Popov, Y
2004-01-01
The paper presents the preliminary results of an ongoing research project on Internet enabled process-based modelling of extended manufacturing enterprises. It is proposed to apply the Open System Architecture for CIM (CIMOSA) modelling framework alongside with object-oriented Petri Net models of enterprise processes and object-oriented techniques for extended enterprises modelling. The main features of the proposed approach are described and some components discussed. Elementary examples of ...
Modern elementary particle physics explaining and extending the standard model
Kane, Gordon
2017-01-01
This book is written for students and scientists wanting to learn about the Standard Model of particle physics. Only an introductory course knowledge about quantum theory is needed. The text provides a pedagogical description of the theory, and incorporates the recent Higgs boson and top quark discoveries. With its clear and engaging style, this new edition retains its essential simplicity. Long and detailed calculations are replaced by simple approximate ones. It includes introductions to accelerators, colliders, and detectors, and several main experimental tests of the Standard Model are explained. Descriptions of some well-motivated extensions of the Standard Model prepare the reader for new developments. It emphasizes the concepts of gauge theories and Higgs physics, electroweak unification and symmetry breaking, and how force strengths vary with energy, providing a solid foundation for those working in the field, and for those who simply want to learn about the Standard Model.
An extended multi-zone combustion model for PCI simulation
Kodavasal, Janardhan; Keum, SeungHwan; Babajimopoulos, Aristotelis
2011-12-01
Novel combustion modes are becoming an important area of research with emission regulations more stringent than ever before, and with fuel economy being assigned greater importance every day. Homogeneous Charge Compression Ignition (HCCI) and Premixed Compression Ignition (PCI) modes in particular promise better fuel economy and lower emissions in internal combustion engines. Multi-zone combustion models have been popular in modelling HCCI combustion. In this work, an improved multi-zone model is suggested for PCI combustion modelling. A new zoning scheme is suggested based on incorporating the internal energy of formation into an earlier conventional HCCI multi-zone approach, which considers a two-dimensional reaction space defined by equivalence ratio and temperature. It is shown that the added dimension improves zoning by creating more representative zones, and thus reducing errors compared to the conventional zoning approach, when applied to PCI simulation.
Overwinding in a stochastic model of an extended polymer
Energy Technology Data Exchange (ETDEWEB)
Bernido, Christopher C. [Research Center for Theoretical Physics, Central Visayan Institute Foundation, Jagna, Bohol 6308 (Philippines)], E-mail: cbernido@mozcom.com; Carpio-Bernido, M. Victoria [Research Center for Theoretical Physics, Central Visayan Institute Foundation, Jagna, Bohol 6308 (Philippines)
2007-09-10
We evaluate explicit expressions of length-dependent winding configuration probabilities for a biopolymer. The stochastic model incorporates several experimentally observed features. In particular, it exhibits overwinding under stretching forces until a critical length of the polymer is reached.
Extended Rasch Modeling: The eRm Package for the Application of IRT Models in R
Directory of Open Access Journals (Sweden)
Patrick Mair
2007-02-01
Full Text Available Item response theory models (IRT are increasingly becoming established in social science research, particularly in the analysis of performance or attitudinal data in psychology, education, medicine, marketing and other fields where testing is relevant. We propose the R package eRm (extended Rasch modeling for computing Rasch models and several extensions. A main characteristic of some IRT models, the Rasch model being the most prominent, concerns the separation of two kinds of parameters, one that describes qualities of the subject under investigation, and the other relates to qualities of the situation under which the response of a subject is observed. Using conditional maximum likelihood (CML estimation both types of parameters may be estimated independently from each other. IRT models are well suited to cope with dichotomous and polytomous responses, where the response categories may be unordered as well as ordered. The incorporation of linear structures allows for modeling the effects of covariates and enables the analysis of repeated categorical measurements. The eRm package fits the following models: the Rasch model, the rating scale model (RSM, and the partial credit model (PCM as well as linear reparameterizations through covariate structures like the linear logistic test model (LLTM, the linear rating scale model (LRSM, and the linear partial credit model (LPCM. We use an unitary, efficient CML approach to estimate the item parameters and their standard errors. Graphical and numeric tools for assessing goodness-of-fit are provided.
Improved Nucleon Properties in the Extended Quark Sigma Model
Abu-Shady, M
2013-01-01
The quark sigma model describes the quarks interacting via exchange the pions and sigma meson fields. A new version of mesonic potential is suggested in the frame of some aspects of the quantum chromodynamics (QCD). The field equations have been solved in the mean-field approximation for the hedgehog baryon state. The obtained results are compared with previous works and other models. We conclude that the suggested mesonic potential successfully calculates nucleon properties.
Extended model of restricted beam for FSO links
Poliak, Juraj; Wilfert, Otakar
2012-10-01
Modern wireless optical communication systems in many aspects overcome wire or radio communications. Their advantages are license-free operation and broad bandwidth that they offer. The medium in free-space optical (FSO) links is the atmosphere. Operation of outdoor FSO links struggles with many atmospheric phenomena that deteriorate phase and amplitude of the transmitted optical beam. This beam originates in the transmitter and is affected by its individual parts, especially by the lens socket and the transmitter aperture, where attenuation and diffraction effects take place. Both of these phenomena unfavourable influence the beam and cause degradation of link availability, or its total malfunction. Therefore, both of these phenomena should be modelled and simulated, so that one can judge the link function prior to the realization of the system. Not only the link availability and reliability are concerned, but also economic aspects. In addition, the transmitted beam is not, generally speaking, circularly symmetrical, what makes the link simulation more difficult. In a comprehensive model, it is necessary to take into account the ellipticity of the beam that is restricted by circularly symmetrical aperture where then the attenuation and diffraction occur. General model is too computationally extensive; therefore simplification of the calculations by means of analytical and numerical approaches will be discussed. Presented model is not only simulated using computer, but also experimentally proven. One can then deduce the ability of the model to describe the reality and to estimate how far can one go with approximations, i.e. limitations of the model are discussed.
Stability analysis of traffic flow with extended CACC control models
Ya-Zhou, Zheng; Rong-Jun, Cheng; Siu-Ming, Lo; Hong-Xia, Ge
2016-06-01
To further investigate car-following behaviors in the cooperative adaptive cruise control (CACC) strategy, a comprehensive control system which can handle three traffic conditions to guarantee driving efficiency and safety is designed by using three CACC models. In this control system, some vital comprehensive information, such as multiple preceding cars’ speed differences and headway, variable safety distance (VSD) and time-delay effect on the traffic current and the jamming transition have been investigated via analytical or numerical methods. Local and string stability criterion for the velocity control (VC) model and gap control (GC) model are derived via linear stability theory. Numerical simulations are conducted to study the performance of the simulated traffic flow. The simulation results show that the VC model and GC model can improve driving efficiency and suppress traffic congestion. Project supported by the National Natural Science Foundation of China (Grant Nos. 71571107 and 11302110). The Scientific Research Fund of Zhejiang Province, China (Grant Nos. LY15A020007, LY15E080013, and LY16G010003). The Natural Science Foundation of Ningbo City (Grant Nos. 2014A610030 and 2015A610299), the Fund from the Government of the Hong Kong Administrative Region, China (Grant No. CityU11209614), and the K C Wong Magna Fund in Ningbo University, China.
Three spacecraft observe Jupiter's glowing polar regions
1996-09-01
again in 1994, when the fragments of Comet Shoemaker-Levy 9 hit Jupiter in a spectacular series of events. The explosive impacts appeared to repress the auroral activity at the time, suggesting a remarkable effect of comet dust on the charged particles creating the aurorae in Jupiter's atmosphere. The new results on variability due to other causes will help astronomers to assess that effect more confidently. They will also compare the 1994 and 1996 IUE data to see how the atmosphere of Jupiter has recovered from the impacts. In Jupiter's vicinity IUE registered ultraviolet emissions from oxygen and sulphur atoms littering the orbit of Io, and probably released by volcanic emissions from that peculiar moon. This Io Torus is highly variable too. The record of its ultraviolet emissions, both within the 1996 campaign and in comparison with earlier observations, will help the astronomers to understand the reasons for the variations. A remarkable history The close scrutiny of Jupiter and its moons was the final astronomical task of IUE, before the termination of space operations on 30 September 1996. Over the past few months the IUE science team and collaborating astronomers in Europe have fulfilled a wish-list of important observations precluded by the intense demands on their ultraviolet space observatory throughout its life of nearly nineteen years. The observations in the final science programme confirmed and extended IUE's record, as the most reliable and productive astronomical satellite that ever flew. In March of this year the spacecraft was ailing, with only one of its six gyros still functioning, which severely limited the scope of its original mission. By skillful control and spacecraft engineering it went on harvesting new data, including prolonged observations of Comet Hyakutake. The concluding campaigns that began in April targeted the gamma-ray emitting "blazar" Markarian 421, various other active galaxies, and stellar winds, as well as Jupiter. "I am sad but
Extending the LCDM model through shear-free anisotropies
Pereira, Thiago S
2016-01-01
If the spacetime metric has anisotropic spatial curvature, one can afford to expand the universe isotropically, provided that the energy-momentum tensor satisfy a certain con- straint. This leads to the so-called shear-free metrics, which have the interesting property of violating the cosmological principle while still preserving the isotropy of the cosmic mi- crowave background (CMB) radiation. In this work we show that shear-free cosmologies correspond to an attractor solution in the space of models with anisotropic spatial curva- ture. Through a rigorous definition of linear perturbation theory in these spacetimes, we show that shear-free models represent a viable alternative to describe the large-scale evo- lution of the universe, leading, in particular, to a kinematically equivalent Sachs-Wolfe effect. Alternatively, we discuss some specific signatures that shear-free models would imprint on the temperature spectrum of CMB.
An extended model for electron spin polarization in photosynthetic bacteria
Energy Technology Data Exchange (ETDEWEB)
Morris, A.L.; Norris, J.R. (Argonne National Lab., IL (USA) Chicago Univ., IL (USA). Dept. of Chemistry); Thurnauer, M.C. (Argonne National Lab., IL (USA))
1990-01-01
We have developed a general model for electron spin polarization which includes contributions from both CIDEP (chemically induced dynamic electron polarization) and CRP (correlated radical polarization). In this paper, we apply this model to sequential electron transfer in photosynthetic bacteria. Our model calculates the density matrix for the P{sup +}I{sup {minus}} radical pair and transfers the polarization as it develops to the P{sup +}Q{sup {minus}} radical pair. We illustrate several possible cases. One case is equivalent to CIDEP; no interactions are included on the secondary radical pair, P{sup +}Q{sup {minus}}. Another approximates CRPP by either increasing the transfer rate from P{sup +}I{sup {minus}} to P{sup +}Q{sup {minus}} or restricting interactions to the secondary radical pair, P{sup +}Q{sup {minus}}. Others allow interactions on both the primary and secondary radical pairs with various transfer rates. 15 refs., 4 figs.
Extending the dimensionality of flatland with attribute view probabilistic models
Neufeld, Eric; Bickis, Mikelis; Grant, Kevin
2008-01-01
In much of Bertin's Semiology of Graphics, marks representing individuals are arranged on paper according to their various attributes (components). Paper and computer monitors can conveniently map two attributes to width and height, and can map other attributes into nonspatial dimensions such as texture, or colour. Good visualizations exploit the human perceptual apparatus so that key relationships are quickly detected as interesting patterns. Graphical models take a somewhat dual approach with respect to the original information. Components, rather than individuals, are represented as marks. Links between marks represent conceptually simple, easily computable, and typically probabilistic relationships of possibly varying strength, and the viewer studies the diagram to discover deeper relationships. Although visually annotated graphical models have been around for almost a century, they have not been widely used. We argue that they have the potential to represent multivariate data as generically as pie charts represent univariate data. The present work suggests a semiology for graphical models, and discusses the consequences for information visualization.
Jupiter's Moons: Family Portrait
2007-01-01
This montage shows the best views of Jupiter's four large and diverse 'Galilean' satellites as seen by the Long Range Reconnaissance Imager (LORRI) on the New Horizons spacecraft during its flyby of Jupiter in late February 2007. The four moons are, from left to right: Io, Europa, Ganymede and Callisto. The images have been scaled to represent the true relative sizes of the four moons and are arranged in their order from Jupiter. Io, 3,640 kilometers (2,260 miles) in diameter, was imaged at 03:50 Universal Time on February 28 from a range of 2.7 million kilometers (1.7 million miles). The original image scale was 13 kilometers per pixel, and the image is centered at Io coordinates 6 degrees south, 22 degrees west. Io is notable for its active volcanism, which New Horizons has studied extensively. Europa, 3,120 kilometers (1,938 miles) in diameter, was imaged at 01:28 Universal Time on February 28 from a range of 3 million kilometers (1.8 million miles). The original image scale was 15 kilometers per pixel, and the image is centered at Europa coordinates 6 degrees south, 347 degrees west. Europa's smooth, icy surface likely conceals an ocean of liquid water. New Horizons obtained data on Europa's surface composition and imaged subtle surface features, and analysis of these data may provide new information about the ocean and the icy shell that covers it. New Horizons spied Ganymede, 5,262 kilometers (3,268 miles) in diameter, at 10:01 Universal Time on February 27 from 3.5 million kilometers (2.2 million miles) away. The original scale was 17 kilometers per pixel, and the image is centered at Ganymede coordinates 6 degrees south, 38 degrees west. Ganymede, the largest moon in the solar system, has a dirty ice surface cut by fractures and peppered by impact craters. New Horizons' infrared observations may provide insight into the composition of the moon's surface and interior. Callisto, 4,820 kilometers (2,995 miles) in diameter, was imaged at 03:50 Universal Time on
Elementary particles, dark matter candidate and new extended standard model
Hwang, Jaekwang
2017-01-01
Elementary particle decays and reactions are discussed in terms of the three-dimensional quantized space model beyond the standard model. Three generations of the leptons and quarks correspond to the lepton charges. Three heavy leptons and three heavy quarks are introduced. And the bastons (new particles) are proposed as the possible candidate of the dark matters. Dark matter force, weak force and strong force are explained consistently. Possible rest masses of the new particles are, tentatively, proposed for the experimental searches. For more details, see the conference paper at https://www.researchgate.net/publication/308723916.
Extending MBI Model using ITIL and COBIT Processes
Directory of Open Access Journals (Sweden)
Sona Karkoskova
2015-10-01
Full Text Available Most organizations today operate in a highly complex and competitive business environment and need to be able to react to rapidly changing market conditions. IT management frameworks are widely used to provide effective support for business objectives through aligning IT with business and optimizing the use of IT resources. In this paper we analyze three IT management frameworks (ITIL, COBIT and MBI with the objective to identify the relationships between these frameworks, and mapping ITIL and COBIT processes to MBI tasks. As a result of this analysis we propose extensions to the MBI model to incorporate IT Performance Management and a Capability Maturity Model.
Extended nonlinear feedback model for describing episodes of high inflation
Szybisz, M A; Szybisz, L.
2016-01-01
An extension of the nonlinear feedback (NLF) formalism to describe regimes of hyper- and high-inflation in economy is proposed in the present work. In the NLF model the consumer price index (CPI) exhibits a finite time singularity of the type $1/(t_c -t)^{(1- \\beta)/\\beta}$, with $\\beta>0$, predicting a blow up of the economy at a critical time $t_c$. However, this model fails in determining $t_c$ in the case of weak hyperinflation regimes like, e.g., that occurred in Israel. To overcome this...
Incommensurate Antiferromagnetism in the Extended t-J Model
Institute of Scientific and Technical Information of China (English)
LIANG Ying; MA Tian-Xing; FENG Shi-Ping; CHEN Wei-Yeu
2002-01-01
The effect of the extra second neighbor hopping t' on the incommensurate spin correlation in the t-J modelin the underdoped regime is studied within the fermion-spin theory. It is shown that although the extra second neighborhopping t' is systematically accompanied with the increasing of the weight of the incommensurate peaks in the dynamicalspin structure factor, for the physical reasonable small value of t' the qualitative behavior of the incommensurate spincorrelation in the t-t'-J model is the same as in the case of t-J model.
Jumping Jupiter can explain Mercury's orbit
Roig, Fernando; DeSouza, Sandro Ricardo
2016-01-01
The orbit of Mercury has large values of eccentricity and inclination that cannot be easily explained if this planet formed on a circular and coplanar orbit. Here, we study the evolution of Mercury's orbit during the instability related to the migration of the giant planets in the framework of the jumping Jupiter model. We found that some instability models are able to produce the correct values of Mercury's eccentricity and inclination, provided that relativistic effects are included in the precession of Mercury's perihelion. The orbital excitation is driven by the fast change of the normal oscillation modes of the system corresponding to the perihelion precession of Jupiter (for the eccentricity), and the nodal regression of Uranus (for the inclination).
Extending radiative transfer models by use of Bayes rule. [in atmospheric science
Whitney, C.
1977-01-01
This paper presents a procedure that extends some existing radiative transfer modeling techniques to problems in atmospheric science where curvature and layering of the medium and dynamic range and angular resolution of the signal are important. Example problems include twilight and limb scan simulations. Techniques that are extended include successive orders of scattering, matrix operator, doubling, Gauss-Seidel iteration, discrete ordinates and spherical harmonics. The procedure for extending them is based on Bayes' rule from probability theory.
An extended topological model for binary phosphate glasses
DEFF Research Database (Denmark)
Hermansen, Christian; Rodrigues, B.P.; Wondraczek, L.
2014-01-01
the model reduces to classical constraint counting. The constraints on the modifying cations are linear constraints to first neighbor NBOs, and all angular constraints are broken as expected for ionic bonding. For small modifying cations, such as Li+, the linear constraints are almost fully intact...
Experimental validation of extended NO and soot model for advanced HD diesel engine combustion
Seykens, X.L.J.; Baert, R.S.G.; Somers, L.M.T.; Willems, F.P.T.
2009-01-01
A computationally efficient engine model is developed based on an extended NO emission model and state-of-the-art soot model. The model predicts exhaust NO and soot emission for both conventional and advanced, high-EGR (up to 50%), heavy-duty DI diesel combustion. Modeling activities have aimed at l
Extending UML-RT for Control System Modeling
Directory of Open Access Journals (Sweden)
Qimin Gao
2004-01-01
Full Text Available There is a growing interest in adopting object technologies for the development of real-time control systems. Several commercial tools, currently available, provide object-oriented modeling and design support for real-time control systems. While these products provide many useful facilities, such as visualization tools and automatic code generation, they are all weak in addressing the central characteristic of real-time control systems design, i.e., providing support for a designer to reason about timeliness properties. We believe an approach that integrates the advancements in both object modeling and design methods and real-time scheduling theory is the key to successful use of object technology for real-time software. Surprisingly several past approaches to integrate the two either restrict the object models, or do not allow sophisticated schedulability analysis techniques. This study shows how schedulability analysis can be integrated with UML for Real-Time (UML-RT to deal with timing properties in real time control systems. More specifically, we develop the schedulability and feasibility analysis modeling for the external messages that may suffer release jitter due to being dispatched by a tick driven scheduler in real-time control system and we also develop the scheduliablity modeling for sporadic activities, where messages arrive sporadically then execute periodically for some bounded time. This method can be used to cope with timing constraints in realistic and complex real-time control systems. Using this method, a designer can quickly evaluate the impact of various implementation decisions on schedulability. In conjunction with automatic code generation, we believe that this will greatly streamline the design and development of real-time control systems software.
Modeling of carbon dioxide absorption by aqueous ammonia solutions using the Extended UNIQUAC model
DEFF Research Database (Denmark)
Darde, Victor Camille Alfred; van Well, Willy J. M.; Stenby, Erling Halfdan
2010-01-01
and the concentration range up to 80 molal ammonia. In this work, the validity of this model was extended up to 150°C and the accuracy improved by increasing the number of experimental data points from 2000 to more than 3500. These experimental data consisting of vapor-liquid equilibrium data in various concentration...... ranges, enthalpy change from partial evaporation measurements, speciation data, heat capacity, enthalpy of solution and enthalpy of dilution data have been used to refit 43 model parameters and standard state properties. Henry’s law constant correlations have been used for extrapolating standard state...
Jupiter's Phase Variations from Cassini: a testbed for future direct-imaging missions
Mayorga, L C; Rages, K; West, R A; Knowles, B; Lewis, N; Marley, M S
2016-01-01
We present phase curves of Jupiter from 0-140 degrees as measured in multiple optical bandpasses by Cassini/ISS during the Millennium flyby of Jupiter in late 2000 to early 2001. Phase curves are of interest for studying the energy balance of Jupiter and understanding the scattering behavior of Jupiter as an exoplanet analog. We find that Jupiter is significantly darker at partial phases than an idealized Lambertian planet by roughly 25% and is not well fit by Jupiter-like exoplanet atmospheric models across all wavelengths. We provide analytic fits to Jupiter's phase function in several Cassini/ISS imaging filter bandpasses. In addition, these observations show that Jupiter's color is more variable with phase angle than predicted by models. Therefore, the color of even a near Jupiter-twin planet observed at a partial phase cannot be assumed to be comparable to that of Jupiter at full phase. We discuss how WFIRST and other future direct-imaging missions can enhance the study of cool giants.
Secular orbital evolution of Jupiter family comets
Rickman, H.; Gabryszewski, R.; Wajer, P.; Wiśniowski, T.; Wójcikowski, K.; Szutowicz, S.; Valsecchi, G. B.; Morbidelli, A.
2017-02-01
Context. The issue of the long term dynamics of Jupiter family comets (JFCs) involves uncertain assumptions about the physical evolution and lifetimes of these comets. Contrary to what is often assumed, real effects of secular dynamics cannot be excluded and therefore merit investigation. Aims: We use a random sample of late heavy bombardment cometary projectiles to study the long-term dynamics of JFCs by a Monte Carlo approach. In a steady-state picture of the Jupiter family, we investigate the orbital distribution of JFCs, including rarely visited domains like retrograde orbits or orbits within the outer parts of the asteroid main belt. Methods: We integrate 100 000 objects over a maximum of 100 000 orbital revolutions including the Sun, a comet, and four giant planets. Considering the steady-state number of JFCs to be proportional to the total time spent in the respective orbital domain, we derive the capture rate based on observed JFCs with small perihelia and large nuclei. We consider a purely dynamical model and one where the nuclei are eroded by ice sublimation. Results: The JFC inclination distribution is incompatible with our erosional model. This may imply that a new type of comet evolution model is necessary. Considering that comets may live for a long time, we show that JFCs can evolve into retrograde orbits as well as asteroidal orbits in the outer main belt or Cybele regions. The steady-state capture rate into the Jupiter family is consistent with 1 × 109 scattered disk objects with diameters D > 2 km. Conclusions: Our excited scattered disk makes it difficult to explain the JFC inclination distribution, unless the physical evolution of JFCs is more intricate than assumed in standard, erosional models. Independent of this, the population size of the Jupiter family is consistent with a relatively low-mass scattered disk.
2000-01-01
[figure removed for brevity, see original site] A four-panel frame shows a section of Jupiter's north equatorial belt viewed by NASA's Cassini spacecraft at four different wavelengths, and a separate reference frame shows the location of the belt on the planet.A fascinating aspect of the images in the four-panel frame is the small bright spot in the center of each. The images come from different layers of the atmosphere, so the spot appears to be a storm penetrating upward through several layers. This may in fact be a 'monster' thunderstorm, penetrating all the way into the stratosphere, as do some summer thunderstorms in the midwestern United States. These images were taken on Nov. 27, 2000, at a resolution of 192 kilometers (119 miles) per pixel. They have been contrast-enhanced to highlight features in the atmosphere.The top panel of the four-panel frame is an image taken in a near-infrared wavelength at which the gases in Jupiter's atmosphere are relatively non-absorbing. Sunlight can penetrate deeply into the atmosphere at this wavelength and be reflected back out, providing a view of an underlying region of the atmosphere, the lower troposphere.The second panel was taken in the blue portion of wavelengths detected by the human eye. At these wavelengths, gases in the atmosphere scatter a modest amount of sunlight, so the clouds we see tend to be at somewhat higher altitudes than in the top panel.The third panel shows near-infrared reflected sunlight at a wavelength where the gas methane, an important constituent of Jupiter's atmosphere, absorbs strongly. Dark places are regions without high-level clouds and consequently large amounts of methane accessible to sunlight. Bright regions are locations with high clouds in the upper troposphere shielding the methane below.The bottom panel was taken in the ultraviolet. At these very short wavelengths, the clear atmosphere scatters sunlight, and hazes in the stratosphere, above the troposphere, absorb sunlight. That
Searches for Neutral Higgs Bosons in Extended Models
Abdallah, J; Adam, W; Adzic, P; Albrecht, T; Alderweireld, T; Alemany-Fernandez, R; Allmendinger, T; Allport, P P; Amaldi, Ugo; Amapane, N; Amato, S; Anashkin, E; Andreazza, A; Andringa, S; Anjos, N; Antilogus, P; Apel, W D; Arnoud, Y; Ask, S; Åsman, B; Augustin, J E; Augustinus, A; Baillon, Paul; Ballestrero, A; Bambade, P; Barbier, R; Bardin, Dimitri Yuri; Barker, G J; Baroncelli, A; Battaglia, Marco; Baubillier, M; Becks, K H; Begalli, M; Behrmann, A; Ben-Haim, E; Benekos, N C; Benvenuti, Alberto C; Bérat, C; Berggren, M; Berntzon, L; Bertrand, D; Besançon, M; Besson, N; Bloch, D; Blom, M; Bluj, M; Bonesini, M; Boonekamp, M; Booth, P S L; Borisov, G; Botner, O; Bouquet, B; Bowcock, T J V; Boyko, I; Bracko, M; Brenner, R; Brodet, E; Brückman, P; Brunet, J M; Bugge, L; Buschmann, P; Calvi, M; Camporesi, T; Canale, V; Carena, F; Castro, N; Cavallo, F R; Chapkin, M M; Charpentier, P; Checchia, P; Chierici, R; Shlyapnikov, P; Chudoba, J; Chung, S U; Cieslik, K; Collins, P; Contri, R; Cosme, G; Cossutti, F; Costa, M J; Crennell, D J; Cuevas-Maestro, J; D'Hondt, J; Dalmau, J; Da Silva, T; Da Silva, W; Della Ricca, G; De Angelis, A; de Boer, Wim; De Clercq, C; De Lotto, B; De Maria, N; De Min, A; De Paula, L S; Di Ciaccio, L; Di Simone, A; Doroba, K; Drees, J; Dris, M; Eigen, G; Ekelöf, T J C; Ellert, M; Elsing, M; Espirito-Santo, M C; Fanourakis, G K; Fassouliotis, D; Feindt, M; Fernández, J; Ferrer, A; Ferro, F; Flagmeyer, U; Föth, H; Fokitis, E; Fulda-Quenzer, F; Fuster, J A; Gandelman, M; García, C; Gavillet, P; Gazis, E N; Gokieli, R; Golob, B; Gómez-Ceballos, G; Gonçalves, P; Graziani, E; Grosdidier, G; Grzelak, K; Guy, J; Haag, C; Hallgren, A; Hamacher, K; Hamilton, K; Haug, S; Hauler, F; Hedberg, V; Hennecke, M; Herr, H; Hoffman, J; Holmgren, S O; Holt, P J; Houlden, M A; Hultqvist, K; Jackson, J N; Jarlskog, G; Jarry, P; Jeans, D; Johansson, E K; Johansson, P D; Jonsson, P; Joram, C; Jungermann, L; Kapusta, F; Katsanevas, S; Katsoufis, E C; Kernel, G; Kersevan, B P; Kerzel, U; Kiiskinen, A P; King, B T; Kjaer, N J; Kluit, P; Kokkinias, P; Kourkoumelis, C; Kuznetsov, O; Krumshtein, Z; Kucharczyk, M; Lamsa, J; Leder, G; Ledroit, F; Leinonen, L; Leitner, R; Lemonne, J; Lepeltier, V; Lesiak, T; Liebig, W; Liko, D; Lipniacka, A; Lopes, J H; López, J M; Loukas, D; Lutz, P; Lyons, L; MacNaughton, J; Malek, A; Maltezos, S; Mandl, F; Marco, J; Marco, R; Maréchal, B; Margoni, M; Marin, J C; Mariotti, C; Markou, A; Martínez-Rivero, C; Masik, J; Mastroyiannopoulos, N; Matorras, F; Matteuzzi, C; Mazzucato, F; Mazzucato, M; McNulty, R; Meroni, C; Migliore, E; Mitaroff, W A; Mjörnmark, U; Moa, T; Moch, M; Mönig, K; Monge, R; Montenegro, J; Moraes, D; Moreno, S; Morettini, P; Müller, U; Münich, K; Mulders, M; Mundim, L; Murray, W; Muryn, B; Myatt, G; Myklebust, T; Nassiakou, M; Navarria, Francesco Luigi; Nawrocki, K; Nicolaidou, R; Nikolenko, M; Oblakowska-Mucha, A; Obraztsov, V F; Olshevskii, A G; Onofre, A; Orava, R; Österberg, K; Ouraou, A; Oyanguren, A; Paganoni, M; Paiano, S; Palacios, J P; Palka, H; Papadopoulou, T D; Pape, L; Parkes, C; Parodi, F; Parzefall, U; Passeri, A; Passon, O; Peralta, L; Perepelitsa, V F; Perrotta, A; Petrolini, A; Piedra, J; Pieri, L; Pierre, F; Pimenta, M; Piotto, E; Podobnik, T; Poireau, V; Pol, M E; Polok, G; Pozdnyakov, V; Pukhaeva, N; Pullia, A; Rames, J; Read, A; Rebecchi, P; Rehn, J; Reid, D; Reinhardt, R; Renton, P B; Richard, F; Rídky, J; Rivero, M; Rodríguez, D; Romero, A; Ronchese, P; Roudeau, P; Rovelli, T; Ruhlmann-Kleider, V; Ryabtchikov, D; Sadovskii, A; Salmi, L; Salt, J; Sander, C; Savoy-Navarro, A; Schwickerath, U; Segar, A; Sekulin, R L; Siebel, M; Sissakian, A N; Smadja, G; Smirnova, O G; Sokolov, A; Sopczak, A; Sosnowski, R; Spassoff, Tz; Stanitzki, M; Stocchi, A; Strauss, J; Stugu, B; Szczekowski, M; Szeptycka, M; Szumlak, T; Tabarelli de Fatis, T; Taffard, A C; Tegenfeldt, F; Timmermans, J; Tkatchev, L G; Tobin, M; Todorovova, S; Tomé, B; Tonazzo, A; Tortosa, P; Travnicek, P; Treille, D; Tristram, G; Trochimczuk, M; Troncon, C; Turluer, M L; Tyapkin, I A; Tyapkin, P; Tzamarias, S; Uvarov, V; Valenti, G; van Dam, P; Van Eldik, J; Van Lysebetten, A; Van Remortel, N; Van Vulpen, I; Vegni, G; Veloso, F; Venus, W; Verdier, P; Verzi, V; Vilanova, D; Vitale, L; Vrba, V; Wahlen, H; Washbrook, A J; Weiser, C; Wicke, D; Wickens, J; Wilkinson, G; Winter, M; Witek, M; Yushchenko, O P; Zalewska-Bak, A; Zalewski, P; Zavrtanik, D; Zhuravlov, V; Zimin, N I; Zintchenko, A; Zupan, M
2004-01-01
Searches for neutral Higgs bosons produced at LEP in association with Z bosons, in pairs and in the Yukawa process are presented in this paper. Higgs boson decays into b quarks, tau leptons, or other Higgs bosons are considered, giving rise to four-b, four-b+jets, six-b and four-tau final states, as well as mixed modes with b quarks and tau leptons. The whole mass domain kinematically accessible at LEP in these topologies is searched. The analysed data set covers both the LEP1 and LEP2 energy ranges and exploits most of the luminosity recorded by the DELPHI experiment. No convincing evidence for a signal is found, and results are presented in the form of mass-dependent upper bounds on coupling factors (in units of model-independent reference cross-sections) for all processes, allowing interpretation of the data in a large class of models.
An extended topological model for binary phosphate glasses
Energy Technology Data Exchange (ETDEWEB)
Hermansen, Christian [Section of Chemistry, Aalborg University, 9220 Aalborg (Denmark); Rodrigues, Bruno P.; Wondraczek, Lothar [Otto Schott Institute of Materials Research, University of Jena, 07743 Jena (Germany); Yue, Yuanzheng, E-mail: yy@bio.aau.dk [Section of Chemistry, Aalborg University, 9220 Aalborg (Denmark); State Key Laboratory of Silicate Materials for Architecture, Wuhan University of Technology, Wuhan 430070 (China)
2014-12-28
We present a topological model for binary phosphate glasses that builds on the previously introduced concepts of the modifying ion sub-network and the strength of modifier constraints. The validity of the model is confirmed by the correct prediction of T{sub g}(x) for covalent polyphosphoric acids where the model reduces to classical constraint counting. The constraints on the modifying cations are linear constraints to first neighbor non-bridging oxygens, and all angular constraints are broken as expected for ionic bonding. For small modifying cations, such as Li{sup +}, the linear constraints are almost fully intact, but for larger ions, a significant fraction is broken. By accounting for the fraction of intact modifying ion related constraints, q{sub γ}, the T{sub g}(x) of alkali phosphate glasses is predicted. By examining alkali, alkaline earth, and rare earth metaphosphate glasses, we find that the effective number of intact constraints per modifying cation is linearly related to the charge-to-distance ratio of the modifying cation to oxygen.
Non-leptonic decays in an extended chiral quark model
Eeg, J O
2012-01-01
We consider the color suppressed (nonfactorizable) amplitude for the decay mode $\\bar{B_{d}^0} \\rightarrow \\pi^0 \\pi^{0} $. We treat the $b$-quark in the heavy quark limit and the energetic light ($u,d,s$) quarks within a variant of Large Energy Effective Theory combined with an extension of chiral quark models. Our calculated amplitude for $\\bar{B_{d}^0} \\rightarrow \\pi^0 \\pi^{0} $ is suppressed by a factor of order $\\Lambda_{QCD}/m_b$ with respect to the factorized amplitude, as it should according to QCD-factorization. Further, for reasonable values of the (model dependent) gluon condensate and the constituent quark mass, the calculated nonfactorizable amplitude for $\\bar{B_{d}^0} \\rightarrow \\pi^0 \\pi^{0} $ can easily accomodate the experimental value. Unfortunately, the color suppressed amplitude is very sensitive to the values of these model dependent parameters. Therefore fine-tuning is necessary in order to obtain an amplitude compatible with the experimental result for $\\bar{B_{d}^0} \\rightarrow \\pi^...
Extended soft-wall model for the QCD phase diagram
Zöllner, Rico; Kampfer, Burkhard
2016-01-01
The soft-wall model, emerging as bottom-up holographic scenario anchored in the AdS/CFT correspondence, displays the disappearance of normalisable modes referring to vector mesons at a temperature $T_{\\dis}$ depending on the chemical potential $\\mu$, $T_{\\dis}(\\mu)$. We explore options for making $T_{\\dis}(\\mu)$ consistent with the freeze-out curve $T_{\\rm f.o.}(\\mu)$ from relativistic heavy-ion collisions and the cross-over curve $T_{\\rm c}(\\mu)$ from QCD at small values of $\\mu$.
Jones, Valerie M.; Rensink, Arend; Brinksma, Hendrik
2005-01-01
Mobile health systems can extend the enterprise computing system of the healthcare provider by bringing services to the patient any time and anywhere. We propose a model-driven design and development methodology for the development of the m-health components in such extended enterprise computing
The Extended Perturbation Method: New Insights on the New Keynesian Model
DEFF Research Database (Denmark)
Andreasen, Martin Møller; Kronborg, Anders Farver
bound on inflation as implied by Calvo pricing. In contrast, extended perturbation generates stable dynamics as it enforces this bound. Extended perturbation also adds to existing evidence on downward nominal wage rigidities in the New Keynesian model, as we only find support for this friction when...
Jones, Val; Rensink, Arend; Brinksma, Ed
2005-01-01
Mobile health systems can extend the enterprise computing system of the healthcare provider by bringing services to the patient any time and anywhere. We propose a model-driven design and development methodology for the development of the m-health components in such extended enterprise computing sys
Chang, Chi-Cheng; Yan, Chi-Fang; Tseng, Ju-Shih
2012-01-01
Since convenience is one of the features for mobile learning, does it affect attitude and intention of using mobile technology? The technology acceptance model (TAM), proposed by David (1989), was extended with perceived convenience in the present study. With regard to English language mobile learning, the variables in the extended TAM and its…
Floquet topological semimetal phases of an extended kicked Harper model
Bomantara, Raditya Weda; Raghava, Gudapati Naresh; Zhou, Longwen; Gong, Jiangbin
2016-02-01
Recent discoveries on topological characterization of gapless systems have attracted interest in both theoretical studies and experimental realizations. Examples of such gapless topological phases are Weyl semimetals, which exhibit three-dimensional (3D) Dirac cones (Weyl points), and nodal line semimetals, which are characterized by line nodes (two bands touching along a line). Inspired by our previous discoveries that the kicked Harper model exhibits many fascinating features of Floquet topological phases, in this paper we consider a generalization of the model, where two additional periodic system parameters are introduced into the Hamiltonian to serve as artificial dimensions, so as to simulate a 3 D periodically driven system. We observe that by increasing the hopping strength and the kicking strength of the system, many new Floquet band touching points at Floquet quasienergies 0 and π will start to appear. Some of them are Weyl points, while the others form line nodes in the parameter space. By taking open boundary conditions along the physical dimension, edge states analogous to Fermi arcs in static Weyl semimetal systems are observed. Finally, by designing an adiabatic pumping scheme, the chirality of the Floquet-band Weyl points and the π Berry phase around Floquet-band line nodes can be manifested.
An extended Cellular Potts Model analyzing a wound healing assay.
Scianna, Marco
2015-07-01
A suitable Cellular Potts Model is developed to reproduce and analyze an in vitro wound-healing assay. The proposed approach is able both to quantify the invasive capacity of the overall cell population and to evaluate selected determinants of single cell movement (velocity, directional movement, and final displacement). In this respect, the present CPM allows us to capture differences and correlations in the migratory behavior of cells initially located at different distances from the wound edge. In the case of an undifferentiated extracellular matrix, the model then predicts that a maximal healing can be obtained by a chemically induced increment of cell elasticity and not by a chemically induced downregulation of intercellular adhesive contacts. Moreover, in the case of two-component substrates (formed by a mesh of collagenous-like threads and by a homogeneous medium), CPM simulations show that both fiber number and cell-fiber adhesiveness influence cell speed and wound closure rate in a biphasic fashion. On the contrary, the topology of the fibrous network affects the healing process by mediating the productive directional cell movement. The paper, also equipped with comments on the computational cost of the CPM algorithm, ends with a throughout discussion of the pertinent experimental and theoretical literature. Copyright © 2015 Elsevier Ltd. All rights reserved.
Extended models of nonlinear waves in liquid with gas bubbles
Kudryashov, Nikolay A
2016-01-01
In this work we generalize the models for nonlinear waves in a gas--liquid mixture taking into account an interphase heat transfer, a surface tension and a weak liquid compressibility simultaneously at the derivation of the equations for nonlinear waves. We also take into consideration high order terms with respect to the small parameter. Two new nonlinear differential equations are derived for long weakly nonlinear waves in a liquid with gas bubbles by the reductive perturbation method considering both high order terms with respect to the small parameter and the above mentioned physical properties. One of these equations is the perturbation of the Burgers equation and corresponds to main influence of dissipation on nonlinear waves propagation. The other equation is the perturbation of the Burgers--Korteweg--de Vries equation and corresponds to main influence of dispersion on nonlinear waves propagation.
Abelian cosmic string in the extended Starobinsky model of gravity
Graça, J P Morais
2016-01-01
We analyze numerically the behaviour of the solutions corresponding to an Abelian cosmic string taking into account an extension of the Starobinsky model, where the action of general relativity is replaced by $f(R) = R - 2\\Lambda + \\eta R^2 + \\rho R^m$, with $m > 2$. As an interesting result, we find that the angular deficit which characterizes the cosmic string decreases as the parameters $\\eta$ and $\\rho$ increase. We also find that the cosmic horizon due to the presence of a cosmological constant is affected in such a way that it can grows or shrinks, depending on the vacuum expectation value of the scalar field and on the value of the cosmological constant
EXTENDE MODEL OF COMPETITIVITY THROUG APPLICATION OF NEW APPROACH DIRECTIVES
Directory of Open Access Journals (Sweden)
Slavko Arsovski
2009-03-01
Full Text Available The basic subject of this work is the model of new approach impact on quality and safety products, and competency of our companies. This work represents real hypothesis on the basis of expert's experiences, in regard to that the infrastructure with using new approach directives wasn't examined until now, it isn't known which product or industry of Serbia is related to directives of the new approach and CE mark, and it is not known which are effects of the use of the CE mark. This work should indicate existing quality reserves and product's safety, the level of possible competency improvement and increasing the profit by discharging new approach directive requires.
Radiation Environment for the Jupiter Europa Orbiter
Jun, Insoo
2008-09-01
One of the major challenges for the Jupiter Europa Orbiter (JEO) mission would be that the spacecraft should be designed to survive an intense radiation environment expected at Jupiter and Europa. The proper definition of the radiation environments is the important first step, because it could affect almost every aspects of mission and spacecraft design. These include optimizing the trajectory to minimize radiation exposure, determining mission lifetime, selecting parts, materials, detectors and sensors, shielding design, etc. The radiation environments generated for the 2008 JEO study will be covered, emphasizing the radiation environment mainly responsible for the total ionizing dose (TID) and displacement damage dose (DDD). The latest models developed at JPL will be used to generate the TID and DDD environments. Finally, the major radiation issues will be summarized, and a mitigation plan will be discussed.
Panel data models extended to spatial error autocorrelation or a spatially lagged dependent variable
Elhorst, J. Paul
2001-01-01
This paper surveys panel data models extended to spatial error autocorrelation or a spatially lagged dependent variable. In particular, it focuses on the specification and estimation of four panel data models commonly used in applied research: the fixed effects model, the random effects model, the
Extended Mixed-Efects Item Response Models with the MH-RM Algorithm
Chalmers, R. Philip
2015-01-01
A mixed-effects item response theory (IRT) model is presented as a logical extension of the generalized linear mixed-effects modeling approach to formulating explanatory IRT models. Fixed and random coefficients in the extended model are estimated using a Metropolis-Hastings Robbins-Monro (MH-RM) stochastic imputation algorithm to accommodate for…
CML based estimation of extended Rasch models with the eRm package in R
Directory of Open Access Journals (Sweden)
PATRICK MAIR
2007-03-01
Full Text Available This paper presents an open source tool for computing extended Rasch models. It is realized in R (R Development Core Team, 2006 and available as package eRm. In addition to ordinary Rasch models extended models such as linear logistic test models, (linear rating scale models and (linear partial credit models can be estimated. A striking feature of this package is the implementation of conditional maximum likelihood estimation techniques which relate directly to Rasch's original concept of specific objectivity. The mathematical and epistemological benefits of this estimation method are discussed. Moreover, the capabilities of the eRm routine with respect to structural item response designs are demonstrated.
Vacuum stability in extended standard model with leptoquark
Bandyopadhyay, Priyotosh
2016-01-01
We investigate the standard model (SM) with extension of a charged scalar having fractional electromagnetic charge of $-1/3$ unit and with lepton and baryon number violating couplings at tree level. Without directly taking part in the electro-weak (EW) symmetry breaking this scalar can affect stability of the EW vacuum via loop effects. The impact of such a scalar i.e., leptoquark on the perturbativity of SM dimensionless couplings as well as on new physics couplings has been studied at two-loop order. The vacuum stability of the Higgs potential is checked using one-loop renormalization group (RG) improved effective potential approach with two-loop beta function for all the couplings. From the stability analysis various bounds are drawn on parameter space by identifying the region corresponding to metastability and stability of the EW vacuum. Later we also address Higgs mass fine-tuning issue via Veltman condition and the presence of such scalar increases the scale up to which the theory can be considered as ...
Imaging Jupiter Radiation Belts At Low Frequencies
Girard, J. N.; de Pater, I.; Zarka, P.; Santos-Costa, D.; Sault, R.; Hess, S.; Cecconi, B.; Fender, R.; Pewg, Lofar
2014-04-01
, at different epochs only provided, each time, glimpses of the spectral content in different observational configurations. As the synchrotron emission frequency peaks at Vmax / E2B (with Vmax in MHz, E, the electron energy in MeV and B, the magnetic field in Gauss), the low frequency content of this emission is associated with low energy electron populations inside the inner belt and the energetic electrons located in regions of weaker magnetic field (at few jovian radii). Therefore, there is much interest in extending and completing the current knowledge of the synchrotron emission from the belts, with low frequency resolved observations. LOFAR, the LOw Frequency ARray (LOFAR) [6], is a giant flexible and digital ground-based radio interferometer operating in the 30-250 MHz band. It brings very high time (~ μs), frequency (~ kHz) and angular resolutions (~1") and huge sensitivity (mJy). In November 2011, a single 10-hour track enabled to cover an entire planetary rotation and led to the first resolved image of the radiation belts between 127- 172 MHz [7,8]. In Feb 2013, an 2×5h30 joint LOFAR/ WSRT observing campaign seized the state of the radiation belts from 45 MHz up to 5 GHz. We will present the current state of the study (imaging, reconstruction method and modeling) of the radiation belts dynamic with this current set of observations. LOFAR can contribute to the understanding of the physics taking place in the inner belt as well as possibly providing a fast and a systematic "diagnostic" of the state of the belts. The latter represents an opportunity to give context and ground-based support for the arrival of JUNO (NASA) scheduled in July 2016 and also for future missions, such as JUICE (ESA), at the vicinity of Jupiter by the exploration of its icy satellites.
Solar wind influence on Jupiter's aurora
Gyalay, Szilard; Vogt, Marissa F.; Withers, Paul; Bunce, Emma J.
2016-10-01
Jupiter's main auroral emission is driven by a system of corotation enforcement currents that arises to speed up outflowing Iogenic plasma and is not due to the magnetosphere-solar wind interaction like at Earth. The solar wind is generally expected to have only a small influence on Jupiter's magnetosphere and aurora compared to the influence of rotational stresses due to the planet's rapid rotation. However, there is considerable observational evidence that the solar wind does affect the magnetopause standoff distance, auroral radio emissions, and the position and brightness of the UV auroral emissions. Using the Michigan Solar Wind Model (mSWiM) to predict the solar wind conditions upstream of Jupiter we have identified intervals of high and low solar wind dynamic pressure in the Galileo dataset, and use this information to quantify how a magnetospheric compression affects the magnetospheric field configuration. We have developed separate spatial fits to the compressed and nominal magnetic field data, accounting for variations with radial distance and local time. These two fits can be used to update the flux equivalence mapping model of Vogt et al. (2011), which links auroral features to source regions in the middle and outer magnetosphere. The updated version accounts for changing solar wind conditions and provides a way to quantify the expected solar wind-induced variability in the ionospheric mapping of the main auroral emission, satellite footprints, and other auroral features. Our results are highly relevant to interpretation of the new auroral observations from the Juno mission.
Structures of the Planets Jupiter and Saturn
Kerley, Gerald I
2013-01-01
New equations of state (EOS) for hydrogen, helium, and compounds containing heavier elements are used to construct models for the structures of the planets Jupiter and Saturn. Good agreement with the gravitational moments J2 and J4 is obtained with a model that uses a two-layer gas envelope, in which the inner region is denser than the outer one, together with a small, dense core. It is possible to match J2 with a homogeneous envelope, but an envelope with a denser inner region is needed to match both moments. The two-layer envelope also gives good agreement with the global oscillation data for Jupiter. In Jupiter, the boundary between the inner and outer envelopes occurs at 319 GPa, with an 8% density increase. In Saturn, it occurs at 227 GPa, with a 69% density increase. The differences between the two planets show that the need for a density increase is not due to EOS errors. It is also shown that helium enrichment cannot be the cause of the density increase. The phenomenon can be explained as the result o...
2000-01-01
[figure removed for brevity, see original site] 619 nm [figure removed for brevity, see original site] 727 nm [figure removed for brevity, see original site] 890 nmImages from NASA's Cassini spacecraft using three different filters reveal cloud structures and movements at different depths in the atmosphere around Jupiter's south pole.Cassini's cameras come equipped with filters that sample three wavelengths where methane gas absorbs light. These are in the red at 619 nanometer (nm) wavelength and in the near-infrared at 727 nm and 890 nm. Absorption in the 619 nm filter is weak. It is stronger in the 727 nm band and very strong in the 890 nm band where 90 percent of the light is absorbed by methane gas. Light in the weakest band can penetrate the deepest into Jupiter's atmosphere. It is sensitive to the amount of cloud and haze down to the pressure of the water cloud, which lies at a depth where pressure is about 6 times the atmospheric pressure at sea level on the Earth). Light in the strongest methane band is absorbed at high altitude and is sensitive only to the ammonia cloud level and higher (pressures less than about one-half of Earth's atmospheric pressure) and the middle methane band is sensitive to the ammonia and ammonium hydrosulfide cloud layers as deep as two times Earth's atmospheric pressure.The images shown here demonstrate the power of these filters in studies of cloud stratigraphy. The images cover latitudes from about 15 degrees north at the top down to the southern polar region at the bottom. The left and middle images are ratios, the image in the methane filter divided by the image at a nearby wavelength outside the methane band. Using ratios emphasizes where contrast is due to methane absorption and not to other factors, such as the absorptive properties of the cloud particles, which influence contrast at all wavelengths.The most prominent feature seen in all three filters is the polar stratospheric haze that makes Jupiter bright near the pole
National Research Council Canada - National Science Library
Huong, Audrey; Ngu, Xavier
2014-01-01
This work presents the use of extended Modified Lambert Beer (MLB) model for accurate and continuous monitoring of percent blood carboxyhemoglobin (COHb) (SCO) and oxyhemoglobin (OxyHb) saturation (SO2...
Extended sigma-model in nontrivially deformed field-antifield formalism
Batalin, Igor A
2015-01-01
We propose an action for the extended sigma - models in the most general setting of the kinetic term allowed in the nontrivially deformed field - antifield formalism. We show that the classical motion equations do naturally take their desired canonical form.
National Aeronautics and Space Administration — Estimation of aerodynamic models for the control of damaged aircraft using an innovative differential vortex lattice method tightly coupled with an extended Kalman...
Institute of Scientific and Technical Information of China (English)
PANG Hou-Rong; PING Jia-Lun; WANG Fan; ZHAO En-Guang
2004-01-01
Promising high strangeness dibaryons are studied by the extended quark delocalization and color screening model. It is shown that besides H particle and di-Ω, there might be other dibaryon candidates worth to be searched experimentally such as NΩ.
Warm Jupiters from secular planet-planet interactions
Petrovich, Cristobal
2016-01-01
Most warm Jupiters (gas-giant planets with $0.1~{\\rm AU}\\lesssim a \\lesssim1$ AU) have pericenter distances that are too large for significant orbital migration by tidal friction. We study the possibility that the warm Jupiters are undergoing secular eccentricity oscillations excited by an outer companion (a planet or star) in an eccentric and/or mutually inclined orbit. In this model the warm Jupiters migrate periodically, in the high-eccentricity phase of the oscillation when the pericenter distance is small, but are typically observed at much lower eccentricities. We show that the steady-state eccentricity distribution of the warm Jupiters migrating by this mechanism is approximately flat, which is consistent with the observed distribution if and only if we restrict the sample to warm Jupiters that have outer companions detected by radial-velocity surveys. The eccentricity distribution of warm Jupiters without companions exhibits a peak at low eccentricities ($e\\lesssim 0.2$) that must be explained by a di...
Cecconi, B.; Hess, S.; Hérique, A.; Santovito, M. R.; Santos-Costa, D.; Zarka, P.; Alberti, G.; Blankenship, D.; Bougeret, J.-L.; Bruzzone, L.; Kofman, W.
2012-02-01
Radar instruments are part of the core payload of the two Europa Jupiter System Mission (EJSM) spacecraft: NASA-led Jupiter Europa Orbiter (JEO) and ESA-led Jupiter Ganymede Orbiter (JGO). At this point of the project, several frequency bands are under study for radar, which ranges between 5 and 50 MHz. Part of this frequency range overlaps with that of the natural jovian radio emissions, which are very intense in the decametric range, below 40 MHz. Radio observations above 40 MHz are free of interferences, whereas below this threshold, careful observation strategies have to be investigated. We present a review of spectral intensity, variability and sources of these radio emissions. As the radio emissions are strongly beamed, it is possible to model the visibility of the radio emissions, as seen from the vicinity of Europa or Ganymede. We have investigated Io-related radio emissions as well as radio emissions related to the auroral oval. We also review the radiation belts synchrotron emission characteristics. We present radio sources visibility products (dynamic spectra and radio source location maps, on still frames or movies), which can be used for operation planning. This study clearly shows that a deep understanding of the natural radio emissions at Jupiter is necessary to prepare the future EJSM radar instrumentation. We show that this radio noise has to be taken into account very early in the observation planning and strategies for both JGO and JEO. We also point out possible synergies with RPW (Radio and Plasma Waves) instrumentations.
Off-site interaction effect in the Extended Hubbard Model with SCRPA method
Harir, S.; Bennai, M.; Boughaleb, Y.
2009-01-01
The Self Consistent Random Phase Approximation (SCRPA) and a Direct Analytical (DA) method are proposed to solve the Extended Hubbard Model in 1D. We have considered an Extended Hubbard Model (EHM) including on-site and off-site interactions for closed chains in one dimension with periodic boundary conditions. The comparison of the SCRPA results with ones obtained by a Direct Analytical approach shows that the SCRPA treats the problem of these closed chains with a rigorous manner. The analysi...
Extended ARMA models for estimating price developments on day-ahead electricity markets
Energy Technology Data Exchange (ETDEWEB)
Swider, Derk J. [Institute of Energy Economics and the Rational Use of Energy, University of Stuttgart, Hessbruehlstr. 49a, 70565 Stuttgart (Germany); Weber, Christoph [University of Duisburg-Essen, Universitaetsstr. 12, 45117 Essen (Germany)
2007-04-15
In this paper extended models for estimating price developments on electricity markets are presented. The models consider deviations from the normality hypothesis of the prices. Based on an ARMA model combination with GARCH, Gaussian-mixture and switching-regime approaches are comparatively discussed. The comparison is based on historic electricity prices of the spot and two reserve markets in Germany. It is shown that the proposed extended models lead to significantly improved representations of the considered stochastic price processes. It is inferred that these models may be preferred for estimating price developments on electricity markets. (author)
Energy Technology Data Exchange (ETDEWEB)
Colonna, G.; Pietanza, L. D. [Istituto di Metodologie Inorganiche e Plasmi, CNR, Via Amendola 144/D, 70126 Bari (Italy); D' Ambrosio, D. [Dipartimento di Ingegneria Meccanica e Aerospaziale, Politecnico di Torino, Corso Duca degli Abruzzi 24, I-10129 Torino (Italy); D' Ammando, G.; Capitelli, M. [Istituto di Metodologie Inorganiche e Plasmi, CNR, Via Amendola 144/D, 70126 Bari, Italy and Dipartimento di Chimica, Universitá degli studi di Bari, Via Orabona 4, 70125 Bari (Italy)
2014-12-09
A state-to-state model of H{sub 2}/He plasmas coupling the master equations for internal distributions of heavy species with the transport equation for the free electrons has been used as a basis for implementing a multi-temperature kinetic model. In the multi-temperature model internal distributions of heavy particles are Boltzmann, the electron energy distribution function is Maxwell, and the rate coefficients of the elementary processes become a function of local temperatures associated to the relevant equilibrium distributions. The state-to-state and multi-temperature models have been compared in the case of a homogenous recombining plasma, reproducing the conditions met during supersonic expansion though converging-diverging nozzles.
Sasaki, S.; Fujimoto, M.; Yano, H.; Takashima, T.; Kasaba, Y.; Takahashi, Y.; Kimura, J.; Funase, R.; Mori, O.; Tsuda, Y.; Campagnola, S.; Kawakatsu, Y.
2011-10-01
In the future Jupiter system study, Coordinated observation of Jovian magnetosphere is one of the important targets of the mission in addition to icy satellites, atmosphere, and interior of Jupiter. JAXA will take a role on the magnetosphere spinner JMO (Jupiter Magnetospheric Orbiter), in addition to JGO (Jupiter Ganymede Orbiter) by ESA and JEO (Jupiter Europa Orbiter) by NASA. We will combine JMO with a proposed solar sail mission of JAXA for Jupiter and one of Trojan asteroids. Since Trojan asteroids could be representing raw solid materials of Jupiter or at least outer solar system bodies, involvement of Trojan observation should enhance the quality of Jupiter system exploration.
Capture of irregular satellites at Jupiter
Energy Technology Data Exchange (ETDEWEB)
Nesvorný, David; Vokrouhlický, David; Deienno, Rogerio [Department of Space Studies, Southwest Research Institute, 1050 Walnut Street, Suite 300, Boulder, CO 80302 (United States)
2014-03-20
The irregular satellites of outer planets are thought to have been captured from heliocentric orbits. The exact nature of the capture process, however, remains uncertain. We examine the possibility that irregular satellites were captured from the planetesimal disk during the early solar system instability when encounters between the outer planets occurred. Nesvorný et al. already showed that the irregular satellites of Saturn, Uranus, and Neptune were plausibly captured during planetary encounters. Here we find that the current instability models present favorable conditions for capture of irregular satellites at Jupiter as well, mainly because Jupiter undergoes a phase of close encounters with an ice giant. We show that the orbital distribution of bodies captured during planetary encounters provides a good match to the observed distribution of irregular satellites at Jupiter. The capture efficiency for each particle in the original transplanetary disk is found to be (1.3-3.6) × 10{sup –8}. This is roughly enough to explain the observed population of jovian irregular moons. We also confirm Nesvorný et al.'s results for the irregular satellites of Saturn, Uranus, and Neptune.
MILES extended : Stellar population synthesis models from the optical to the infrared
Rock, B.; Vazdekis, A.; Ricciardelli, E.; Peletier, R. F.; Knapen, J. H.; Falcon-Barroso, J.
2016-01-01
We present the first single-burst stellar population models, which covers the optical and the infrared wavelength range between 3500 and 50 000 angstrom and which are exclusively based on empirical stellar spectra. To obtain these joint models, we combined the extended MILES models in the optical wi
1979-01-01
This picture shows a special color reconstruction of one of the erupting volcanos on Io discovered by Voyager 1 during its encounter with Jupiter on the 4th and 5th of March. The picture was taken March 4 about 5:00 p.m. from a range of about half a million kilometers showing an eruption region on the horizon. This method of color analysis allows scientists to combine data from four pictures, taken in ultraviolet, blue, green and orange light. In this picture one can see the strong change in color of the erupting plume. The region that is brighter in ultraviolet light (blue in this image) is much more extensive than the denser, bright yellow region near the center of the eruption. Scientists will use data of this type to study the amount of gas and dust in the eruption and the size of dust particles. Preliminary analysis suggests that the bright ultraviolet part of the cloud may be due to scattered light from very fine particles (the same effect which makes smoke appear bluish).
Taylor, G. Jeffrey
2003-01-01
Jupiter's moon Io is the most volcanically active body in the Solar System. Observations by instruments on the Galileo spacecraft and on telescopes atop Mauna Kea in Hawai'i indicate that lava flows on Io are surprisingly hot, over 1200 oC and possibly as much as 1300 oC; a few areas might have lava flows as hot as 1500 oC. Such high temperatures imply that the lava flows are composed of rock that formed by a very large amount of melting of Io's mantle. This has led Laszlo Keszthelyi and Alfred S. McEwen of the University of Arizona and me to reawaken an old hypothesis that suggests that the interior of Io is a partially-molten mush of crystals and magma. The idea, which had fallen out of favor for a decade or two, explains high-temperature hot spots, mountains, calderas, and volcanic plains on Io. If correct, Io gives us an opportunity to study processes that operate in huge, global magma systems, which scientists believe were important during the early history of the Moon and Earth, and possibly other planetary bodies as well. Though far from proven, the idea that Io has a ocean of mushy magma beneath its crust can be tested with measurements by future spacecraft.
Achilleos, N. A.; Guio, P.; Arridge, C. S.; Ray, L. C.; Yates, J. N.; Fossey, S.; Savini, G.; Pearson, M.; Fernando, N.; Gerasimov, R.; Murat, T.
2016-12-01
The advent of new missions to the Jovian system such as Juno (recentlyarrived) and JUICE (scheduled for 2022 launch) makes timely the provision of model-based predictions for thephysical conditions to be encountered by these spacecraft; as well as the planning of simultaneous, ground-basedobservations of the Jovian system.Using the UCL Jovian magnetodisc model, which calculates magnetic field and plasma distributionsaccording to Caudal's (1986) force-balance formalism, we provide predictions of the following quantities alongrepresentative Juno / JUICE orbits through the middle magnetosphere: (i) Magnetic field strength and direction; (ii)Density and / or pressure of the 'cold' and 'hot' particle populations; (iii) Plasma angular velocity.The characteristic variation in these parameters is mainly influenced by the periodic approaches towards andrecessions from the magnetodisc imposed on the 'synthetic spacecraft' by the planet's rotating, tilteddipole field. We also include some corresponding predictions for ionospheric / thermospheric conditions at themagnetic footpoint of the spacecraft, using the JASMIN model (Jovian Atmospheric Simulatorwith Magnetosphere, Ionosphere and Neutrals).We also present preliminary imaging results from `IoSpot', a planned, ground-based programme of observationsbased at the University College London Observatory (UCLO) which targets ionized sulphur emissions from the Ioplasma torus. Such programmes, conducted simultaneously with the above missions, will provide valuable context forthe overall physical conditions within the Jovian magnetosphere, for which Io's volcanoes are the principal source ofplasma.
Achilleos, Nicholas; Guio, Patrick; Arridge, Christopher S.; Ray, Licia C.; Yates, Japheth N.; Fossey, Stephen J.; Savini, Giorgio; Pearson, Mick; Fernando, Nathalie; Gerasimov, Roman; Murat, Thomas
2016-10-01
The advent of new missions to the Jovian system such as Juno (recently arrived) and JUICE (scheduled for 2022 launch) makes timely the provision of model-based predictions for the physical conditions to be encountered by these spacecraft; as well as the planning of simultaneous, ground-based observations of the Jovian system.Using the UCL Jovian magnetodisc model, which calculates magnetic field and plasma distributionsaccording to Caudal's (1986) force-balance formalism, we provide predictions of the following quantities along representative Juno / JUICE orbits through the middle magnetosphere: (i) Magnetic field strength and direction; (ii) Density and / or pressure of the 'cold' and 'hot' particle populations; (iii) Plasma angular velocity.The characteristic variation in these parameters is mainly influenced by the periodic approaches towards and recessions from the magnetodisc imposed on the 'synthetic spacecraft' by the planet's rotating, tilteddipole field. We also include some corresponding predictions for ionospheric / thermospheric conditions at the magnetic footpoint of the spacecraft, using the JASMIN model (Jovian Atmospheric Simulatorwith Magnetosphere, Ionosphere and Neutrals).We also present preliminary imaging results from 'IoSpot', a planned, ground-based programme of observations based at the University College London Observatory (UCLO) which targets ionized sulphur emissions from the Io plasma torus. Such programmes, conducted simultaneously with the above missions, will provide valuable context for the overall physical conditions within the Jovian magnetosphere, for which Io's volcanoes are the principal source of plasma.
Dorbath, Felix; Nagel, Björn; Gollnick, Volker
2011-01-01
This paper introduces the concept of the ELWIS model generator for Finite Element models of aircraft wing structures. The physical modelling of the structure is extended beyond the wing primary structures, to increase the level of accuracy for aircraft which diverge from existing configurations. Also the impact of novel high lift technologies on structural masses can be captured already in the early stages of design by using the ELWIS models. The ELWIS model generator is able to c...
Tilting Saturn without tilting Jupiter: Constraints on giant planet migration
Brasser, R
2015-01-01
The migration and encounter histories of the giant planets in our Solar System can be constrained by the obliquities of Jupiter and Saturn. We have performed secular simulations with imposed migration and N-body simulations with planetesimals to study the expected obliquity distribution of migrating planets with initial conditions resembling those of the smooth migration model, the resonant Nice model and two models with five giant planets initially in resonance (one compact and one loose configuration). For smooth migration, the secular spin-orbit resonance mechanism can tilt Saturn's spin axis to the current obliquity if the product of the migration time scale and the orbital inclinations is sufficiently large (exceeding 30 Myr deg). For the resonant Nice model with imposed migration, it is difficult to reproduce today's obliquity values, because the compactness of the initial system raises the frequency that tilts Saturn above the spin precession frequency of Jupiter, causing a Jupiter spin-orbit resonance...
A Bayesian Reformulation of the Extended Drift-Diffusion Model in Perceptual Decision Making
Fard, Pouyan R.; Park, Hame; Warkentin, Andrej; Kiebel, Stefan J.; Bitzer, Sebastian
2017-01-01
Perceptual decision making can be described as a process of accumulating evidence to a bound which has been formalized within drift-diffusion models (DDMs). Recently, an equivalent Bayesian model has been proposed. In contrast to standard DDMs, this Bayesian model directly links information in the stimulus to the decision process. Here, we extend this Bayesian model further and allow inter-trial variability of two parameters following the extended version of the DDM. We derive parameter distributions for the Bayesian model and show that they lead to predictions that are qualitatively equivalent to those made by the extended drift-diffusion model (eDDM). Further, we demonstrate the usefulness of the extended Bayesian model (eBM) for the analysis of concrete behavioral data. Specifically, using Bayesian model selection, we find evidence that including additional inter-trial parameter variability provides for a better model, when the model is constrained by trial-wise stimulus features. This result is remarkable because it was derived using just 200 trials per condition, which is typically thought to be insufficient for identifying variability parameters in DDMs. In sum, we present a Bayesian analysis, which provides for a novel and promising analysis of perceptual decision making experiments. PMID:28553219
A Bayesian Reformulation of the Extended Drift-Diffusion Model in Perceptual Decision Making
Directory of Open Access Journals (Sweden)
Pouyan R. Fard
2017-05-01
Full Text Available Perceptual decision making can be described as a process of accumulating evidence to a bound which has been formalized within drift-diffusion models (DDMs. Recently, an equivalent Bayesian model has been proposed. In contrast to standard DDMs, this Bayesian model directly links information in the stimulus to the decision process. Here, we extend this Bayesian model further and allow inter-trial variability of two parameters following the extended version of the DDM. We derive parameter distributions for the Bayesian model and show that they lead to predictions that are qualitatively equivalent to those made by the extended drift-diffusion model (eDDM. Further, we demonstrate the usefulness of the extended Bayesian model (eBM for the analysis of concrete behavioral data. Specifically, using Bayesian model selection, we find evidence that including additional inter-trial parameter variability provides for a better model, when the model is constrained by trial-wise stimulus features. This result is remarkable because it was derived using just 200 trials per condition, which is typically thought to be insufficient for identifying variability parameters in DDMs. In sum, we present a Bayesian analysis, which provides for a novel and promising analysis of perceptual decision making experiments.
Zhang, Lei; Zeng, Zhi; Ji, Qiang
2011-09-01
Chain graph (CG) is a hybrid probabilistic graphical model (PGM) capable of modeling heterogeneous relationships among random variables. So far, however, its application in image and video analysis is very limited due to lack of principled learning and inference methods for a CG of general topology. To overcome this limitation, we introduce methods to extend the conventional chain-like CG model to CG model with more general topology and the associated methods for learning and inference in such a general CG model. Specifically, we propose techniques to systematically construct a generally structured CG, to parameterize this model, to derive its joint probability distribution, to perform joint parameter learning, and to perform probabilistic inference in this model. To demonstrate the utility of such an extended CG, we apply it to two challenging image and video analysis problems: human activity recognition and image segmentation. The experimental results show improved performance of the extended CG model over the conventional directed or undirected PGMs. This study demonstrates the promise of the extended CG for effective modeling and inference of complex real-world problems.
Types of Hot Jupiter Atmospheres
Bisikalo, Dmitry V.; Kaygorodov, Pavel V.; Ionov, Dmitry E.; Shematovich, Valery I.
Hot Jupiters, i.e. exoplanet gas giants, having masses comparable to the mass of Jupiter and semimajor axes shorter than 0.1 AU, are a unique class of objects. Since they are so close to the host stars, their atmospheres form and evolve under the action of very active gas dynamical processes caused by the gravitational field and irradiation of the host star. As a matter of fact, the atmospheres of several of these planets fill their Roche lobes , which results in a powerful outflow of material from the planet towards the host star. The energy budget of this process is so important that it almost solely governs the evolution of hot Jupiters gaseous envelopes. Based on the years of experience in the simulations of gas dynamics in mass-exchanging close binary stars, we have investigated specific features of hot Jupiters atmospheres. The analytical estimates and results of 3D numerical simulations, discussed in this Chapter, show that the gaseous envelopes around hot Jupiters may be significantly non-spherical and, at the same time, stationary and long-lived. These results are of fundamental importance for the interpretation of observational data.
Jupiter and Saturn Rotation Periods
Helled, Ravit; Anderson, John D
2009-01-01
Anderson & Schubert (2007, Science,317,1384) proposed that Saturn's rotation period can be ascertained by minimizing the dynamic heights of the 100 mbar isosurface with respect to the geoid; they derived a rotation period of 10h 32m 35s. We investigate the same approach for Jupiter to see if the Jovian rotation period is predicted by minimizing the dynamical heights of its isobaric (1 bar pressure level) surface using zonal wind data. A rotation period of 9h 54m 29s is found. Further, we investigate the minimization method by fitting Pioneer and Voyager occultation radii for both Jupiter and Saturn. Rotation periods of 9h 55m 30s and 10h 32m 35s are found to minimize the dynamical heights for Jupiter and Saturn, respectively. Though there is no dynamical principle requiring the minimization of the dynamical heights of an isobaric surface, the successful application of the method to Jupiter lends support to its relevance for Saturn. We derive Jupiter and Saturn rotation periods using equilibrium theory in ...
Nucleon Properties at Finite Temperature in the Extended Quark-Sigma Model
Abu-Shady, M
2014-01-01
Hadron properties are studied at hot medium using the quark sigma model. The quark sigma model is extended to include eighth-order of mesonic interactions based on some aspects of quantum chromodynamic (QCD) theory. The extended effective potential tends to the original effective potential when the coupling between the higher order mesonic interactions equal to zero. The field equations have been solved in the mean-field approximation by using the extended iteration method. We found that the nucleon mass increases with increasing temperature and the magnetic moments of proton and neutron increase with increasing temperature. A comparison is presented with recent previous works and other models. We conclude that higher-order mesonic interactions play an important role in changing the behavior of nucleon properties at finite temperature. In addition, the deconfinement phase transition is satisfied in the present model.
Advancing the extended parallel process model through the inclusion of response cost measures.
Rintamaki, Lance S; Yang, Z Janet
2014-01-01
This study advances the Extended Parallel Process Model through the inclusion of response cost measures, which are drawbacks associated with a proposed response to a health threat. A sample of 502 college students completed a questionnaire on perceptions regarding sexually transmitted infections and condom use after reading information from the Centers for Disease Control and Prevention on the health risks of sexually transmitted infections and the utility of latex condoms in preventing sexually transmitted infection transmission. The questionnaire included standard Extended Parallel Process Model assessments of perceived threat and efficacy, as well as questions pertaining to response costs associated with condom use. Results from hierarchical ordinary least squares regression demonstrated how the addition of response cost measures improved the predictive power of the Extended Parallel Process Model, supporting the inclusion of this variable in the model.
Energy Technology Data Exchange (ETDEWEB)
Summers, Cathy A.; Oryshchyn, Danylo B.; Ochs, Thomas L.; Turner, Paul C.
2005-06-30
In January of 2004, a Cooperative Research and Development Agreement was signed with the Jupiter Oxygen Corporation; its term extends from January 2004 to January 1, 2009. The statement of work is attached as Appendix A. Under Phase I of this agreement, ARC was to provide technical expertise to develop computer models of existing power plants relative to retrofitting with oxy-fuel combustion; help design experiments to verify models and analyze data from experiments; help produce designs at larger scales; help design a new technology oxy-fuel power plant; and co-author technical papers on this work for presentation at appropriate conferences.
△△ Dibaryon Structure in Extended Chiral SU(3) Quark Model
Institute of Scientific and Technical Information of China (English)
DAI Lian-Rong
2005-01-01
@@ The structure of △△ dibaryon is studied in the extended chiral SU(3) quark model in which vector meson exchanges are included. The effect of the vector meson fields is very similar to that of the one-gluon exchange (OGE) interaction. Both in the chiral SU(3) quark model and in the extended chiral SU(3) quark model, the resultant mass of the △△ dibaryon is lower than the threshold of the △△ channel but higher than that of the△Nπ channel.
Extending the Real-Time Maude Semantics of Ptolemy to Hierarchical DE Models
Bae, Kyungmin; 10.4204/EPTCS.36.3
2010-01-01
This paper extends our Real-Time Maude formalization of the semantics of flat Ptolemy II discrete-event (DE) models to hierarchical models, including modal models. This is a challenging task that requires combining synchronous fixed-point computations with hierarchical structure. The synthesis of a Real-Time Maude verification model from a Ptolemy II DE model, and the formal verification of the synthesized model in Real-Time Maude, have been integrated into Ptolemy II, enabling a model-engineering process that combines the convenience of Ptolemy II DE modeling and simulation with formal verification in Real-Time Maude.
Jupiter Europa Orbiter Architecture Definition Process
Rasmussen, Robert; Shishko, Robert
2011-01-01
The proposed Jupiter Europa Orbiter mission, planned for launch in 2020, is using a new architectural process and framework tool to drive its model-based systems engineering effort. The process focuses on getting the architecture right before writing requirements and developing a point design. A new architecture framework tool provides for the structured entry and retrieval of architecture artifacts based on an emerging architecture meta-model. This paper describes the relationships among these artifacts and how they are used in the systems engineering effort. Some early lessons learned are discussed.
A Quasi-Nonmetric Method for Multidimensional Scaling via an Extended Euclidean Model.
Winsberg, Suzanne; Carroll, J. Douglas
1989-01-01
An Extended Two-Way Euclidean Multidimensional Scaling (MDS) model that assumes both common and specific dimensions is described and contrasted with the "standard" (Two-Way) MDS model. Illustrations with both artificial and real data on the judged similarity of nations are provided. (TJH)
3D Printed Molecules and Extended Solid Models for Teaching Symmetry and Point Groups
Scalfani, Vincent F.; Vaid, Thomas P.
2014-01-01
Tangible models help students and researchers visualize chemical structures in three dimensions (3D). 3D printing offers a unique and straightforward approach to fabricate plastic 3D models of molecules and extended solids. In this article, we prepared a series of digital 3D design files of molecular structures that will be useful for teaching…
A kinetic type extended model for dense gases and macromolecular fluids
Directory of Open Access Journals (Sweden)
M. Cristina Carrisi
2005-05-01
Full Text Available Extended thermodynamics is an important theory which is appreciated from mathematicians and physicists. Following its ideas and considering the macroscopic approach with suggestions from the kinetic one, we find in this paper, the solution of an interesting model: the model for dense gases and macromolecular fluids.
3D Printed Molecules and Extended Solid Models for Teaching Symmetry and Point Groups
Scalfani, Vincent F.; Vaid, Thomas P.
2014-01-01
Tangible models help students and researchers visualize chemical structures in three dimensions (3D). 3D printing offers a unique and straightforward approach to fabricate plastic 3D models of molecules and extended solids. In this article, we prepared a series of digital 3D design files of molecular structures that will be useful for teaching…
Klein, Daniel; Zezula, Ivan
The extended growth curve model is discussed in this paper. There are two versions of the model studied in the literature, which differ in the way how the column spaces of the design matrices are nested. The nesting is applied either to the between-individual or to the within-individual design
Determining the inventory impact of extended-shelf-life platelets with a network simulation model.
Blake, John T
2017-09-06
The regulatory shelf life for platelets (PLTs) in many jurisdictions is 5 days. PLT shelf life can be extended to 7 days with an enhanced bacterial detection algorithm. Enhanced testing, however, comes at a cost, which may be offset by reductions in wastage due to longer shelf life. This article describes a method for estimating systemwide reductions in PLT outdates after PLT shelf life is extended. A simulation was used to evaluate the impact of an extended PLT shelf life within a national blood network. A network model of the Canadian Blood Services PLT supply chain was built and validated. PLT shelf life was extended from 5 days to 6, 7, and 8 days and runs were completed to determine the impact on outdates. Results suggest that, in general, a 16.3% reduction in PLT wastage can be expected with each additional day that PLT shelf life is extended. Both suppliers and hospitals will experience fewer outdating units, but wastage will decrease at a faster rate at hospitals. No effect was seen by blood group, but there was some evidence that supplier site characteristics influences both the number of units wasted and the site's ability to benefit from extended-shelf-life PLTs. Extended-shelf-life PLTs will reduce wastage within a blood supply chain. At 7 days, an improvement of 38% reduction in wastage can be expected with outdates being equally distributed between suppliers and hospital customers. © 2017 AABB.
Transitions in the cloud composition of hot Jupiters
Parmentier, Vivien; Fortney, Jonathan J.; Showman, Adam; Morley, Caroline; Marley, Mark S.
2016-10-01
Over a large range of equilibrium temperatures, clouds shape the transmission spectrum of hot Jupiter atmospheres, yet their composition remains unknown. Recent observations show that the Kepler lightcurves of some hot Jupiters are asymmetric: for the hottest planets, the lightcurve peaks before secondary eclipse, whereas for planets cooler than 1900K, it peaks after secondary eclipse. We use the thermal structure from 3D global circulation models to determine the expected cloud distribution and Kepler lightcurves of hot Jupiters. We demonstrate that the change from an optical lightcurve dominated by thermal emission to one dominated by scattering (reflection) naturally explains the observed trend from negative to positive offset. For the cool planets the presence of an asymmetry in the Kepler lightcurve is a telltale sign of the cloud composition, because each cloud species can produce an offset only over a narrow range of effective temperatures. By comparing our models and the observations, we show that the cloud composition of hot Jupiters likely varies with equilibrium temperature. We suggest that a transition occurs between silicate and manganese sulfide clouds at a temperature near 1600K, analogous to the L/T transition on brown dwarfs. The cold trapping of cloud species below the photosphere naturally produces such a transition and predicts similar transitions for other condensates, including TiO. We predict that most hot Jupiters should have cloudy nightsides, that partial cloudiness should be common at the limb and that the dayside hot spot should often be cloud-free.
Extended hierarchy equation of motion for the spin-boson model.
Tang, Zhoufei; Ouyang, Xiaolong; Gong, Zhihao; Wang, Haobin; Wu, Jianlan
2015-12-14
An extended hierarchy equation of motion (HEOM) is proposed and applied to study the dynamics of the spin-boson model. In this approach, a complete set of orthonormal functions are used to expand an arbitrary bath correlation function. As a result, a complete dynamic basis set is constructed by including the system reduced density matrix and auxiliary fields composed of these expansion functions, where the extended HEOM is derived for the time derivative of each element. The reliability of the extended HEOM is demonstrated by comparison with the stochastic Hamiltonian approach under room-temperature classical ohmic and sub-ohmic noises and the multilayer multiconfiguration time-dependent Hartree theory under zero-temperature quantum ohmic noise. Upon increasing the order in the hierarchical expansion, the result obtained from the extended HOEM systematically converges to the numerically exact answer.
Roy, Kunal; Ghosh, Gopinath
2008-11-01
In this communication, we have developed quantitative predictive models using human lethal concentration values of 26 organic compounds including some pharmaceuticals with extended topochemical atom (ETA) indices applying different chemometric tools and compared the extended topochemical atom models with the models developed from non-extended topochemical atom ones. Extended topochemical atom descriptors were also tried in combination with non-extended topochemical atom descriptors to develop better predictive models. The use of extended topochemical atom descriptors along with non-extended topochemical atom ones improved equation statistics and cross-validation quality. The best model with sound statistical quality was developed from partial least squares regression using extended topochemical atom descriptors in combination non-extended topochemical atom ones. Finally, to check true predictability of the ETA parameters, the data set was divided into training (n = 19) and test (n = 7) sets. Partial least squares and genetic partial least squares models were developed from the training set using extended topochemical atom indices and the models were validated using the test set. The extended topochemical atom models developed from different statistical tools suggest that the toxicity increases with bulk, chloro functionality, presence of electronegative atoms within a chain or ring and unsaturation, and decreases with hydroxy functionality and branching. The results suggest that the extended topochemical atom descriptors are sufficiently rich in chemical information to encode the structural features for QSAR/QSPR/QSTR modeling.
An Extended Ontology Model and Ontology Checking Based on Description Logics
Institute of Scientific and Technical Information of China (English)
王洪伟; 蒋馥; 吴家春
2004-01-01
Ontology is defined as an explicit specification of a conceptualization. In this paper, an extended ontology model was constructed using description logics, which is a 5-tuples including term set, individual set, term definition set, instantiation assertion set and term restriction set. Based on the extended model, the issue on ontology checking was studied with the conclusion that the four kinds of term checking, including term satisfiability checking, term subsumption checking, term equivalence checking and term disjointness checking, can be reduced to the satisfiability checking, and satisfiability checking can be transformed into instantiation consistence checking.
Atmospheric Circulation of Hot Jupiters: Dayside-Nightside Temperature Differences
Komacek, Thaddeus D
2016-01-01
The full-phase infrared light curves of low-eccentricity hot Jupiters show a trend of increasing dayside-to-nightside brightness temperature difference with increasing equilibrium temperature. Here we present a three-dimensional model that explains this relationship, in order to shed insight on the processes that control heat redistribution in tidally-locked planetary atmospheres. This three-dimensional model combines predictive analytic theory for the atmospheric circulation and dayside-nightside temperature differences over a range of equilibrium temperature, atmospheric composition, and potential frictional drag strengths with numerical solutions of the circulation that verify this analytic theory. This analytic theory shows that the longitudinal propagation of waves mediates dayside-nightside temperature differences in hot Jupiter atmospheres, analogous to the wave adjustment mechanism that regulates the thermal structure in Earth's tropics. These waves can be damped in hot Jupiter atmospheres by either r...
Ohmic Dissipation in the Atmospheres of Hot Jupiters
Perna, Rosalba; Rauscher, Emily
2010-01-01
Hot Jupiter atmospheres exhibit fast, weakly-ionized winds. The interaction of these winds with the planetary magnetic field generates drag on the winds and leads to ohmic dissipation of the induced electric currents. We study the magnitude of ohmic dissipation in representative, three-dimensional atmospheric circulation models of the hot Jupiter HD 209458b. We find that ohmic dissipation can reach or exceed 1% of the stellar insolation power in the deepest atmospheric layers, in models with and without dragged winds. Such power, dissipated in the deep atmosphere, appears sufficient to slow down planetary contraction and explain the typically inflated radii of hot Jupiters. This atmospheric scenario does not require a top insulating layer or radial currents that penetrate deep in the planetary interior. Circulation in the deepest atmospheric layers may actually be driven by spatially non-uniform ohmic dissipation. A consistent treatment of magnetic drag and ohmic dissipation is required to further elucidate t...
First Results of the Juno Magnetometer Investigation in Jupiter's Magnetosphere
Connerney, Jack; Oliversen, Ronald; Espley, Jared; Kotsiaros, Stavros; Joergensen, John; Joergensen, Peter; Merano, Jose; Denver, Troelz; Benn, Mathias; Bloxham, Jeremy; Bolton, Scott; Levin, Steve
2017-04-01
The Juno spacecraft entered polar orbit about Jupiter on July 4, 2016, after a Jupiter Orbit Insertion (JOI) main engine burn lasting 35 minutes. Juno's science instruments were not powered during the critical maneuver sequence ( 5 days) but were fully operational shortly afterward. The 53.5-day capture orbit provides Juno's science instruments with the opportunity to sample the Jovian environment close up (to 1.06 Jovian radii, Rj) and in polar orbit extending to the outer reaches of the Jovian magnetosphere. Jupiter's gravity and magnetic fields will be globally mapped with unprecedented accuracy as Juno conducts a study of Jupiter's interior structure and composition, as well as the first comprehensive exploration of the polar magnetosphere. The magnetic field investigation onboard Juno is equipped with two magnetometer sensor suites, located at 10 and 12 m from the spacecraft body at the end of one of the three solar panel wings. Each contains a vector fluxgate magnetometer (FGM) sensor and a pair of co-located non-magnetic star tracker camera heads which provide accurate attitude determination for the FGM sensors. The first few periapsis passes available to date revealed an extraordinary spatial variation of the magnetic field close to the planet's surface, suggesting that Juno may be sampling the field closer to the dynamo region than widely anticipated, i.e., portending a dynamo surface extending to relatively large radial distance ( 0.9Rj?). We present the first observations of Jupiter's magnetic field obtained in close proximity to the planet, and speculate on what wonders await as more longitudes are drawn across the global map (32 polar orbits separated by designed to acquire.
CAPTURE OF TROJANS BY JUMPING JUPITER
Energy Technology Data Exchange (ETDEWEB)
Nesvorny, David [Department of Space Studies, Southwest Research Institute, 1050 Walnut St., Suite 300, Boulder, CO 80302 (United States); Vokrouhlicky, David [Institute of Astronomy, Charles University, V Holesovickach 2, 180 00 Prague 8 (Czech Republic); Morbidelli, Alessandro [Departement Cassiopee, University of Nice, CNRS, Observatoire de la Cote d' Azur, Nice, F-06304 (France)
2013-05-01
Jupiter Trojans are thought to be survivors of a much larger population of planetesimals that existed in the planetary region when planets formed. They can provide important constraints on the mass and properties of the planetesimal disk, and its dispersal during planet migration. Here, we tested a possibility that the Trojans were captured during the early dynamical instability among the outer planets (aka the Nice model), when the semimajor axis of Jupiter was changing as a result of scattering encounters with an ice giant. The capture occurs in this model when Jupiter's orbit and its Lagrange points become radially displaced in a scattering event and fall into a region populated by planetesimals (that previously evolved from their natal transplanetary disk to {approx}5 AU during the instability). Our numerical simulations of the new capture model, hereafter jump capture, satisfactorily reproduce the orbital distribution of the Trojans and their total mass. The jump capture is potentially capable of explaining the observed asymmetry in the number of leading and trailing Trojans. We find that the capture probability is (6-8) Multiplication-Sign 10{sup -7} for each particle in the original transplanetary disk, implying that the disk contained (3-4) Multiplication-Sign 10{sup 7} planetesimals with absolute magnitude H < 9 (corresponding to diameter D = 80 km for a 7% albedo). The disk mass inferred from this work, M{sub disk} {approx} 14-28 M{sub Earth}, is consistent with the mass deduced from recent dynamical simulations of the planetary instability.
The Europa Jupiter System Mission
Hendrix, A. R.; Clark, K.; Erd, C.; Pappalardo, R.; Greeley, R. R.; Blanc, M.; Lebreton, J.; van Houten, T.
2009-05-01
Europa Jupiter System Mission (EJSM) will be an international mission that will achieve Decadal Survey and Cosmic Vision goals. NASA and ESA have concluded a joint study of a mission to Europa, Ganymede and the Jupiter system with orbiters developed by NASA and ESA; contributions by JAXA are also possible. The baseline EJSM architecture consists of two primary elements operating in the Jovian system: the NASA-led Jupiter Europa Orbiter (JEO), and the ESA-led Jupiter Ganymede Orbiter (JGO). The JEO mission has been selected by NASA as the next Flagship mission to the out solar system. JEO and JGO would execute an intricately choreographed exploration of the Jupiter System before settling into orbit around Europa and Ganymede, respectively. JEO and JGO would carry eleven and ten complementary instruments, respectively, to monitor dynamic phenomena (such as Io's volcanoes and Jupiter's atmosphere), map the Jovian magnetosphere and its interactions with the Galilean satellites, and characterize water oceans beneath the ice shells of Europa and Ganymede. EJSM will fully addresses high priority science objectives identified by the National Research Council's (NRC's) Decadal Survey and ESA's Cosmic Vision for exploration of the outer solar system. The Decadal Survey recommended a Europa Orbiter as the highest priority outer planet flagship mission and also identified Ganymede as a highly desirable mission target. EJSM would uniquely address several of the central themes of ESA's Cosmic Vision Programme, through its in-depth exploration of the Jupiter system and its evolution from origin to habitability. EJSM will investigate the potential habitability of the active ocean-bearing moons Europa and Ganymede, detailing the geophysical, compositional, geological and external processes that affect these icy worlds. EJSM would also explore Io and Callisto, Jupiter's atmosphere, and the Jovian magnetosphere. By understanding the Jupiter system and unraveling its history, the
Tarhini, Ali; Elyas, Tariq; Akour, Mohammad Ali; Al-Salti, Zahran
2016-01-01
The main aim of this paper is to develop an amalgamated conceptual model of technology acceptance that explains how individual, social, cultural and organizational factors affect the students' acceptance and usage behaviour of the Web-based learning systems. More specifically, the proposed model extends the Technology Acceptance Model (TAM) to…
Directory of Open Access Journals (Sweden)
E. E. Woodfield
2013-10-01
Full Text Available Jupiter has the most intense radiation belts of all the outer planets. It is not yet known how electrons can be accelerated to energies of 10 MeV or more. It has been suggested that cyclotron-resonant wave-particle interactions by chorus waves could accelerate electrons to a few MeV near the orbit of Io. Here we use the chorus wave intensities observed by the Galileo spacecraft to calculate the changes in electron flux as a result of pitch angle and energy diffusion. We show that, when the bandwidth of the waves and its variation with L are taken into account, pitch angle and energy diffusion due to chorus waves is a factor of 8 larger at L-shells greater than 10 than previously shown. We have used the latitudinal wave intensity profile from Galileo data to model the time evolution of the electron flux using the British Antarctic Survey Radiation Belt (BAS model. This profile confines intense chorus waves near the magnetic equator with a peak intensity at ∼5° latitude. Electron fluxes in the BAS model increase by an order of magnitude for energies around 3 MeV. Extending our results to L = 14 shows that cyclotron-resonant interactions with chorus waves are equally important for electron acceleration beyond L = 10. These results suggest that there is significant electron acceleration by cyclotron-resonant interactions at Jupiter contributing to the creation of Jupiter's radiation belts and also increasing the range of L-shells over which this mechanism should be considered.
XMM-Newton X-Ray Observation of Jupiter
Waite, J. Hunter
2005-01-01
Soft X-ray emission has been observed from the disk of both Jupiter and Saturn as well as from the auroral regions of these planets. The low-latitude disk emission as observed by ROSAT, the Chandra X-Ray Observatory, and XMM-Newton appears to be uniformly distributed across the disk and to be correlated with solar activity. These characteristics suggest that the disk x-rays are produced by: (1) the elastic scattering of solar X-rays by atmospheric neutrals and (2) the absorption of solar X-rays in the carbon K-shell followed by fluorescent emission. The carbon atoms are found in methane molecules located below the homopause. In this paper we present the results of calculations of the scattering albedo for soft x-rays. We also show the calculated x-ray intensity for a range of atmospheric abundances for Jupiter and Saturn and for a number of solar irradiance spectra. The model calculations are compared with recent x-ray observations of Jupiter and Saturn. We conclude that the emission of soft x-rays from the disks of Jupiter and Saturn can be largely explained by the scattering and fluorescence of soft x-rays. We suggest that measured x-ray intensities from the disk regions of Jupiter
Super-Eccentric Migrating Jupiters
Socrates, Aristotle; Dong, Subo; Tremaine, Scott
2011-01-01
An important class of formation theories for hot Jupiters involves the excitation of extreme orbital eccentricity (e=0.99 or even larger) followed by tidal dissipation at periastron passage that eventually circularizes the planetary orbit at a period less than 10 days. In a steady state, this mechanism requires the existence of a significant population of super-eccentric (e>0.9) migrating Jupiters with long orbital periods and periastron distances of only a few stellar radii. For these super-eccentric planets, the periastron is fixed due to conservation of orbital angular momentum and the energy dissipated per orbit is constant, implying that the rate of change in semi-major axis a is \\dot a \\propto a^0.5 and consequently the number distribution satisfies dN/dlog a\\propto a^0.5. If this formation process produces most hot Jupiters, Kepler should detect several super-eccentric migrating progenitors of hot Jupiters, allowing for a test of high-eccentricity migration scenarios.
SUPER-ECCENTRIC MIGRATING JUPITERS
Energy Technology Data Exchange (ETDEWEB)
Socrates, Aristotle; Katz, Boaz; Dong Subo; Tremaine, Scott [Institute for Advanced Study, Princeton, NJ 08540 (United States)
2012-05-10
An important class of formation theories for hot Jupiters involves the excitation of extreme orbital eccentricity (e = 0.99 or even larger) followed by tidal dissipation at periastron passage that eventually circularizes the planetary orbit at a period less than 10 days. In a steady state, this mechanism requires the existence of a significant population of super-eccentric (e > 0.9) migrating Jupiters with long orbital periods and periastron distances of only a few stellar radii. For these super-eccentric planets, the periastron is fixed due to conservation of orbital angular momentum and the energy dissipated per orbit is constant, implying that the rate of change in semi-major axis a is a-dot {proportional_to}a{sup 1/2} and consequently the number distribution satisfies dN/d log a{proportional_to}a{sup 1/2}. If this formation process produces most hot Jupiters, Kepler should detect several super-eccentric migrating progenitors of hot Jupiters, allowing for a test of high-eccentricity migration scenarios.
Jupiter: Cosmic Jekyll and Hyde.
Grazier, Kevin R
2016-01-01
It has been widely reported that Jupiter has a profound role in shielding the terrestrial planets from comet impacts in the Solar System, and that a jovian planet is a requirement for the evolution of life on Earth. To evaluate whether jovians, in fact, shield habitable planets from impacts (a phenomenon often referred to as the "Jupiter as shield" concept), this study simulated the evolution of 10,000 particles in each of the jovian inter-planet gaps for the cases of full-mass and embryo planets for up to 100 My. The results of these simulations predict a number of phenomena that not only discount the "Jupiter as shield" concept, they also predict that in a Solar System like ours, large gas giants like Saturn and Jupiter had a different, and potentially even more important, role in the evolution of life on our planet by delivering the volatile-laden material required for the formation of life. The simulations illustrate that, although all particles occupied "non-life threatening" orbits at their onset of the simulations, a significant fraction of the 30,000 particles evolved into Earth-crossing orbits. A comparison of multiple runs with different planetary configurations revealed that Jupiter was responsible for the vast majority of the encounters that "kicked" outer planet material into the terrestrial planet region, and that Saturn assisted in the process far more than has previously been acknowledged. Jupiter also tends to "fix" the aphelion of planetesimals at its orbit irrespective of their initial starting zones, which has the effect of slowing their passages through the inner Solar System, and thus potentially improving the odds of accretion of cometary material by terrestrial planets. As expected, the simulations indicate that the full-mass planets perturb many objects into the deep outer Solar System, or eject them entirely; however, planetary embryos also did this with surprising efficiency. Finally, the simulations predict that Jupiter's capacity to
Saab, Rim; Tausch, Nicole; Spears, Russell; Cheung, Wing-Yee
2015-01-01
We examined predictors of collective action among bystander group members in solidarity with a disadvantaged group by extending the dual pathway model of collective action, which proposes one efficacy-based and one emotion-based path to collective action (Van Zomeren, Spears, Fischer, & Leach, 2004)
Stall Recovery in a Centrifuge-Based Flight Simulator With an Extended Aerodynamic Model
Ledegang, W.D.; Groen, E.L.
2015-01-01
We investigated the performance of 12 airline pilots in recovering from an asymmetrical stall in a flight simulator featuring an extended aerodynamic model of a transport-category aircraft, and a centrifuge-based motion platform capable of generating enhanced buffet motion and g-cueing. All pilots h
New phases in an extended Hubbard model explicitly including atomic polarizabilities
Brink, van de J.; Meinders, M.B.J.; Lorenzana, J.; Eder, R.; Sawatzky, G.A.
1996-01-01
We consider the influence of a nearest-neighbor Coulomb interaction in an extended Hubbard model and introduce a new interaction term which simulates atomic polarizabilities. This has the effect of screening the on-site Coulomb interaction for charged excitations, unlike a neighbor Coulomb interacti
Extended sigma-model in nontrivially deformed field-antifield formalism
Batalin, Igor A.; Lavrov, Peter M.
2015-08-01
We propose an action for the extended sigma-models in the most general setting of the kinetic term allowed in the nontrivially deformed field-antifield formalism. We show that the classical motion equations do naturally take their desired canonical form.
Nucleon-Nucleon Phase Shifts in the Extended Quark-Delocalization Colour-Screening Model
Institute of Scientific and Technical Information of China (English)
LU Xi-Feng; PING Jia-Lun; WANG Fan
2003-01-01
An alternative method is applied to the study of nucleon-nucleon scattering phase shifts within the framework of the extended quark demoralization colour-screening model, in which the one-pion exchange with short-range cutoff is included.
Invariance of an Extended Technology Acceptance Model Across Gender and Age Group
Ahmad, Tunku Badariah Tunku; Madarsha, Kamal Basha; Zainuddin, Ahmad Marzuki; Ismail, Nik Ahmad Hisham; Khairani, Ahmad Zamri; Nordin, Mohamad Sahari
2011-01-01
In this study, we examined the likelihood of a TAME (extended technology acceptance model), in which the interrelationships among computer self-efficacy, perceived usefulness, intention to use and self-reported use of computer-mediated technology were tested. In addition, the gender- and age-invariant of its causal structure were evaluated. The…
Featured Image: Mapping Jupiter with Hubble
Kohler, Susanna
2016-07-01
Zonal wind profile for Jupiter, describing the speed and direction of its winds at each latitude. [Simon et al. 2015]This global map of Jupiters surface (click for the full view!) was generated by the Hubble Outer Planet Atmospheres Legacy (OPAL) program, which aims to createnew yearly global maps for each of the outer planets. Presented in a study led by Amy Simon (NASA Goddard Space Flight Center), the map above is the first generated for Jupiter in the first year of the OPAL campaign. It provides a detailed look at Jupiters atmospheric structure including the Great Red Spot and allowed the authors to measure the speed and direction of the wind across Jupiters latitudes, constructing an updated zonal wind profile for Jupiter.In contrast to this study, the Juno mission (which will be captured into Jupiters orbit today after a 5-year journey to Jupiter!) will be focusing more on the features below Jupiters surface, studying its deep atmosphere and winds. Some of Junos primary goals are to learn about Jupiters composition, gravitational field, magnetic field, and polar magnetosphere. You can follow along with the NASATV livestream as Juno arrives at Jupiter tonight; orbit insertion coverage starts at 10:30 EDT.CitationAmy A. Simon et al 2015 ApJ 812 55. doi:10.1088/0004-637X/812/1/55
2000-01-01
Jupiter's four largest satellites, including Io, the golden ornament in front of Jupiter in this image from NASA's Cassini spacecraft, have fascinated Earthlings ever since Galileo Galilei discovered them in 1610 in one of his first astronomical uses of the telescope.Images from Cassini that will be released over the next several days capture each of the four Galilean satellites in their orbits around the giant planet.This true-color composite frame, made from narrow angle images taken on Dec. 12, 2000, captures Io and its shadow in transit against the disk of Jupiter. The distance of the spacecraft from Jupiter was 19.5 million kilometers (12.1 million miles). The image scale is 117 kilometers (73 miles) per pixel.The entire body of Io, about the size of Earth's Moon, is periodically flexed as it speeds around Jupiter and feels, as a result of its non-circular orbit, the periodically changing gravitational pull of the planet. The heat arising in Io's interior from this continual flexure makes it the most volcanically active body in the solar system, with more than 100 active volcanoes. The white and reddish colors on its surface are due to the presence of different sulfurous materials. The black areas are silicate rocks.Cassini is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini mission for NASA's Office of Space Science, Washington, D.C.
A transition in the composition of clouds in hot Jupiters
Parmentier, Vivien; Showman, Adam P; Morley, Caroline V; Marley, Mark S
2016-01-01
Over a large range of equilibrium temperatures, clouds shape the transmission spectrum of hot Jupiter atmospheres, yet their composition remains unknown. Recent observations show that the \\emph{Kepler} lightcurves of some hot Jupiters are asymmetric: for the hottest planets, the lightcurve peaks before secondary eclipse, whereas for planets cooler than $\\sim1900\\,\\rm K$, it peaks after secondary eclipse. In this paper we use the thermal structure from 3D global circulation models to determine the expected cloud distribution and \\emph{Kepler} lightcurves of hot Jupiters. We demonstrate that the change from a visible lightcurve dominated by thermal emission to one dominated by scattering (reflection) naturally explains the observed trend from negative to positive offset. For the cool planets the presence of an asymmetry in the \\emph{Kepler} lightcurve is a telltale sign of the cloud composition, because each cloud species can produce an offset only over a narrow range of effective temperatures. Silicate clouds ...
Low-lying Photoexcited States of a One-Dimensional Ionic Extended Hubbard Model
Yokoi, Kota; Maeshima, Nobuya; Hino, Ken-ichi
2017-10-01
We investigate the properties of low-lying photoexcited states of a one-dimensional (1D) ionic extended Hubbard model at half-filling. Numerical analysis by using the full and Lanczos diagonalization methods shows that, in the ionic phase, there exist low-lying photoexcited states below the charge transfer gap. As a result of comparison with numerical data for the 1D antiferromagnetic (AF) Heisenberg model, it was found that, for a small alternating potential Δ, these low-lying photoexcited states are spin excitations, which is consistent with a previous analytical study [Katsura et al., Phys. Rev. Lett. 103, 177402 (2009)]. As Δ increases, the spectral intensity of the 1D ionic extended Hubbard model rapidly deviates from that of the 1D AF Heisenberg model and it is clarified that this deviation is due to the neutral-ionic domain wall, an elementary excitation near the neutral-ionic transition point.
Stability analysis of the extended ADI-FDTD technique including lumped models
Institute of Scientific and Technical Information of China (English)
CHEN ZhiHui; CHU QingXin
2008-01-01
The numerical stability of the extended alternating-direction-implicit-finite-difference-time-domain (ADI-FDTD) method including lumped models is analyzed.Three common lumped models are investigated:resistor,capacitor,and inductor,and three different formulations for each model are analyzed:the explicit,semi-implicit and implicit schemes.Analysis results show that the extended ADI-FDTD algorithm is not unconditionally stable in the explicit scheme case,and the stability criterion depends on the value of lumped models,but in the semi-implicit and implicit cases,the algorithm is stable.Finally,two simple microstrip circuits including lumped elements are simulated to demonstrate validity of the theoretical results.
Hydro-mechanical modeling of impermeable discontinuity in rock by extended finite element method
Institute of Scientific and Technical Information of China (English)
郑安兴; 罗先启
2015-01-01
The extended finite element method(XFEM) is a numerical method for modeling discontinuities within the classical finite element framework. The computation mesh in XFEM is independent of the discontinuities, such that remeshing for moving discontinuities can be overcome. The extended finite element method is presented for hydro-mechanical modeling of impermeable discontinuities in rock. The governing equation of XFEM for hydraulic fracture modeling is derived by the virtual work principle of the fracture problem considering the water pressure on crack surface. The coupling relationship between water pressure gradient on crack surface and fracture opening width is obtained by semi-analytical and semi-numerical method. This method simplifies coupling analysis iteration and improves computational precision. Finally, the efficiency of the proposed method for modeling hydraulic fracture problems is verified by two examples and the advantages of the XFEM for hydraulic fracturing analysis are displayed.
Applying TAM in B2C E-Commerce Research: An Extended Model
Institute of Scientific and Technical Information of China (English)
QIU Lingyun; LI Dong
2008-01-01
As one of the most widely accepted adoption models in information systems research, the technology acceptance model (TAM) focuses exclusively on cognition-oriented constructs such as perceived usefulness and perceived ease of use. This perspective may have limited the explanatory power of TAM when it is utilized in studying consumers' adoption intentions of online shopping. Based on the contrasts between e-commerce systems and traditional workplace information systems as well as empirical findings from a variety of recent e-commerce research works, this paper analyzes an extended model which integrates three additional constructs: trust, social presence, and perceived enjoyment. The interrelationship between these constructs is also explained. Empirical validations of this extended model are expected in future research.
Fading of Jupiter's South Equatorial Belt
Sola, Michael A.; Orton, Glenn; Baines, Kevin; Yanamandra-Fisher, Padma
2011-01-01
One of Jupiter's most dominant features, the South Equatorial Belt, has historically gone through a "fading" cycle. The usual dark, brownish clouds turn white, and after a period of time, the region returns to its normal color. Understanding this phenomenon, the latest occurring in 2010, will increase our knowledge of planetary atmospheres. Using the near infrared camera, NSFCAM2, at NASA's Infrared Telescope Facility in Hawaii, images were taken of Jupiter accompanied by data describing the circumstances of each observation. These images are then processed and reduced through an IDL program. By scanning the central meridian of the planet, graphs were produced plotting the average values across the central meridian, which are used to find variations in the region of interest. Calculations using Albert4, a FORTRAN program that calculates the upwelling reflected sunlight from a designated cloud model, can be used to determine the effects of a model atmosphere due to various absorption, scattering, and emission processes. Spectra that were produced show ammonia bands in the South Equatorial Belt. So far, we can deduce from this information that an upwelling of ammonia particles caused a cloud layer to cover up the region. Further investigations using Albert4 and other models will help us to constrain better the chemical make up of the cloud and its location in the atmosphere.
The Transit Spectra of Earth and Jupiter
Irwin, Patrick G J; Bowles, Neil E; Fletcher, Leigh N; Aigrain, Suzanne; Lee, Jae-Min
2014-01-01
In recent years, a number of observations have been made of the transits of 'Hot Jupiters', such as HD 189733b, which have been modelled to derive atmospheric structure and composition. As measurement techniques improve, the transit spectra of 'Super-Earths' such as GJ 1214b are becoming better constrained, allowing model atmospheres to be fitted for this class of planet also. While it is not yet possible to constrain the atmospheric states of small planets such as the Earth or cold planets like Jupiter, this may become practical in the coming decades and if so, it is of interest to determine what we might infer from such measurements. Here we have constructed atmospheric models of the Solar System planets from 0.4 - 15.5 microns that are consistent with ground-based and satellite observations and from these calculate the primary transit and secondary eclipse spectra (with respect to the Sun and typical M-dwarfs) that would be observed by a 'remote observer', many light years away. From these spectra we test ...
Recent Simulations of the Late Stages Growth of Jupiter
Lissauer, Jack J.; D'Angelo, Gennaro; Hubickyj, Olenka
2012-01-01
Presented by Lissauer et al. (2009, Icarus 199, 338) are used to test the model of capture of Jupiter's irregular satellites within proto-Jupiter's distended and thermally-supported envelope. We find such capture highly unlikely, since the envelope shrinks too slowly for a large number of moons to be retained, and many of those that would be retained would orbit closer to the planet than do the observed Jovian irregulars. Our calculations do not address (and therefore do not exclude) the possibility that the irregular satellites were captured as a result of gas drag within a circumjovian disk. Support for this research from NASA Outer Planets Research Program is gratefully acknowledged.
Inheritance Optimization of Extend Case Transfer Model of Interoganization Workflows Management
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
Extend case transfer architecture inter-organization workflow management fits the needs of Collaboration commerce. However, during the third step of extend case transfer architecture, modifications of private workflows might cause some fatal problems, such as dead locks, live locks and dead tasks. These problems could change the soundness and efficiency of overall work flow. This paper presents a Petri net based approach to protect the inheritance of public work flows in private domains, and discusses an implementation of our collaboration commerce workflow model.
Scattering resonances and two-particle bound states of the extended Hubbard model
Energy Technology Data Exchange (ETDEWEB)
Valiente, M; Petrosyan, D [Institute of Electronic Structure and Laser, FORTH, 71110 Heraklion, Crete (Greece)
2009-06-28
We present a complete derivation of two-particle states of the one-dimensional extended Bose-Hubbard model involving attractive or repulsive on-site and nearest-neighbour interactions. We find that this system possesses scattering resonances and two families of energy-dependent interaction-bound states which are not present in the Hubbard model with the on-site interaction alone. (fast track communication)
2011-01-01
Modeling phase is fundamental both in the analysis process of a dynamic system and the design of a control system. If this phase is in-line is even more critical and the only information of the system comes from input/output data. Some adaptation algorithms for fuzzy system based on extended Kalman filter are presented in this paper, which allows obtaining accurate models without renounce the computational efficiency that characterizes the Kalman filter, and allows ...
A Possibly Universal Red Chromophore for Jupiter
Sromovsky, Lawrence A.; Baines, Kevin; Fry, Patrick M.
2016-10-01
A new laboratory-generated chemical compound made from photodissociated ammonia (NH3) molecules reacting with acetylene (C2H2) was suggested as a possible coloring agent for Jupiter's Great Red Spot (GRS) by Carlson et al. (2016, Icarus 274, 106-115). Baines et al. (2016, AAS/DPS Meeting abstract) showed that the GRS spectrum measured by the visual channels of the Cassini VIMS instrument in 2000 could be accurately fit by a cloud model in which the chromophore appeared as small particles in a physically thin layer immediately above the main cloud layer of the GRS. Here we show that the same chromophore and similar layer structure can also provide close matches to the 0.4-1 micron spectra of many other cloud features on Jupiter, suggesting that this material may be a nearly universal chromophore responsible for the various degrees of red coloration on Jupiter. This is a robust conclusion, even for 12 percent changes in VIMS calibration and large uncertainties in the refractive index of the main cloud layer due to uncertain fractions of NH4SH and NH3 in its cloud particles. The chromophore layer can account for color variations among north and south equatorial belts, equatorial zone, and the Great Red Spot, by varying particle size from 0.12 to 0.29 micron and optical depth from 0.06 to 0.76. The total mass of the chromophore layer is much less variable than its optical depth, staying mainly within 6-10 micrograms/cm2 range, but is only about half that amount in the equatorial zone. We also found a depression of the ammonia volume mixing ratio in the two belt regions, which averaged 0.4-0.5 × 10-4 immediately below the ammonia condensation level, while the other regions averaged twice that value.LAS and PMF acknowledge support from NASA Grant NNX14AH40G.
A Local Search Modeling for Constrained Optimum Paths Problems (Extended Abstract
Directory of Open Access Journals (Sweden)
Quang Dung Pham
2009-10-01
Full Text Available Constrained Optimum Path (COP problems appear in many real-life applications, especially on communication networks. Some of these problems have been considered and solved by specific techniques which are usually difficult to extend. In this paper, we introduce a novel local search modeling for solving some COPs by local search. The modeling features the compositionality, modularity, reuse and strengthens the benefits of Constrained-Based Local Search. We also apply the modeling to the edge-disjoint paths problem (EDP. We show that side constraints can easily be added in the model. Computational results show the significance of the approach.
Observed light yield of scintillation pixels: Extending the two-ray model
Kantorski, Igor; Jurkowski, Jacek; Drozdowski, Winicjusz
2016-09-01
In this paper we propose an extended, two dimensional model describing the propagation of scintillation photons inside a cuboid crystal until they reach a PMT window. In the simplest approach the model considers two main reasons for light losses: standard absorption obeying the classical Lambert-Beer law and non-ideal reflectivity of the "mummy" covering formed by several layers of Teflon tape wrapping the sample. Results of the model calculations are juxtaposed with experimental data as well as with predictions of an earlier, one dimensional model.
DEFF Research Database (Denmark)
Jeong, Cheol-Ho
2011-01-01
Room surfaces have been extensively modeled as locally reacting in room acoustic predictions although such modeling could yield significant errors under certain conditions. Therefore, this study aims to propose a guideline for adopting the local reaction assumption by comparing predicted random...... incidence acoustical characteristics of typical building elements made of porous materials assuming extended and local reaction. For each surface reaction, five well-established wave propagation models, the Delany-Bazley, Miki, Beranek, Allard-Champoux, and Biot model, are employed. Effects of the flow...
Extending the Standard Model Effective Field Theory with the Complete Set of Dimension-7 Operators
Lehman, Landon
2014-01-01
We present a complete list of the independent dimension-7 operators that are constructed using the Standard Model degrees of freedom and are invariant under the Standard Model gauge group. This list contains only 20 independent operators; far fewer than the 63 operators available at dimension 6. All of these dimension-7 operators contain fermions and violate lepton number, and 7 of the 20 violate baryon number as well. This result extends the Standard Model Effective Field Theory (SMEFT) and allows a more detailed exploration of the structure and properties of possible deformations from the Standard Model Lagrangian.
Extending the standard model effective field theory with the complete set of dimension-7 operators
Lehman, Landon
2014-12-01
We present a complete list of the independent dimension-7 operators that are constructed using the standard model degrees of freedom and are invariant under the standard model gauge group. This list contains only 20 independent operators, far fewer than the 63 operators available at dimension 6. All of these dimension-7 operators contain fermions and violate lepton number, and 7 of the 20 violate baryon number as well. This result extends the standard model effective field theory and allows a more detailed exploration of the structure and properties of possible deformations from the standard model Lagrangian.
Fernandes, Josh; Orton, Glenn S.; Sinclair, James; Kasaba, Yasumasa; Sato, Takao M.; Fujiyoshi, Takuya; Momary, Thomas W.; Yanamandra-Fisher, Padma A.
2016-10-01
We report characterization of the physical and chemical properties of Jupiter's polar regions derived from mid-infrared imaging of Jupiter covering all longitudes at unprecedented spatial resolution using the COMICS instrument at the Subaru Telescope on the nights of January 24 and 25, 2016 (UT). Because of Jupiter's slight axial tilt of 3°, the low angular resolution and incomplete longitudinal coverage of previous mid-infrared observations, the physical and chemical properties of Jupiter's polar regions have been poorly characterized. In advance of the Juno mission's exploration of the polar regions, this study focuses on mapping the 3-dimensional structure of Jupiter's polar regions, specifically to characterize the polar vortices and compact regions of auroral influence. Using mid-infrared images taken in the 7.8 - 24.2 µm range, we determined the 3-dimensional temperature field, mapped the para-H2 fraction and aerosol opacity at 700 mbar and lower pressures, and constrained the distribution of gaseous NH3 in Jupiter's northern and southern polar regions. Retrievals of these atmospheric parameters was performed using NEMESIS, a radiative transfer forward model and retrieval code. Preliminary results indicate that there are vortices at both poles, each with very distinct low-latitude boundaries approximately 60° (planetocentric) from the equator, which can be defined by sharp thermal gradients extending at least from the upper troposphere (500 mbar) and into the stratosphere (0.1 mbar). These polar regions are characterized by lower temperatures, lower aerosol number densities, and lower NH3 volume mixing ratios, compared with the regions immediately outside the vortex boundaries. These images also provided the highest resolution of prominent auroral-related stratospheric heating to date, revealing a teardrop-shaped morphology in the north and a sharp-edged oval shape in the south. Both appear to be contained inside the locus of H3+ auroral emission detected
Directory of Open Access Journals (Sweden)
M. V. Nezlin
1999-01-01
Full Text Available Three kinds of results have been described in this paper. Firstly, an experimental study of the Rossby vortex meridional drift on the rotating shallow water has been carried out. Owing to the stringent physical analogy between the Rossby vortices and drift vortices in the magnetized plasma, the results obtained have allowed one to make a conclusion that the transport rate of the plasma, trapped by the drift vortices, across the magnetic field is equivalent to the “gyro-Bohm” diffusion coefficient. Secondly, a model of big vortices of the type of the Great Red Spot of Jupiter, dominating in the atmospheres of the outer planets, has been produced. Thirdly, the rotating shallow water modeling has been carried out of the hydrodynamical generation mechanism of spiral structures in galaxies. Trailing spiral waves of various azimuthal modes, generated by a shear flow between fast rotating “nucleus” and slow rotating periphery, were produced. The spirals are similar to those existing in the real galaxies. The hydrodynamical concept of the spiral structure formation in galaxies has been substantiated. Strong anticyclonic vortices between the spiral arms of the structures under study have been discovered for the first time. The existence of analogous vortices in real galaxies has been predicted. (This prediction has been reliably confirmed recently in special astronomical observations, carried out on the basis of the mentioned laboratory modeling and the prediction made – see the paper by A. Fridman et al. (Astrophysics and Space Science, 1997, 252, 115.
Tilting Jupiter (a bit) and Saturn (a lot) During Planetary Migration
Vokrouhlicky, David
2015-01-01
We study the effects of planetary late migration on the gas giants obliquities. We consider the planetary instability models from Nesvorny & Morbidelli (2012), in which the obliquities of Jupiter and Saturn can be excited when the spin-orbit resonances occur. The most notable resonances occur when the $s_7$ and $s_8$ frequencies, changing as a result of planetary migration, become commensurate with the precession frequencies of Jupiter's and Saturn's spin vectors. We show that Jupiter may have obtained its present obliquity by crossing of the $s_8$ resonance. This would set strict constrains on the character of migration during the early stage. Additional effects on Jupiter's obliquity are expected during the last gasp of migration when the $s_7$ resonance was approached. The magnitude of these effects depends on the precise value of the Jupiter's precession constant. Saturn's large obliquity was likely excited by capture into the $s_8$ resonance. This probably happened during the late stage of planetary ...
Modeling and Extended State Observer Based Dynamic Surface Control for Cold Rolling Mill System
Directory of Open Access Journals (Sweden)
Xu Li
2016-01-01
Full Text Available The modeling and control problems are investigated for cold rolling mill system. Firstly, we establish a monitor automatic gauge control (MAGC model for a practical cold rolling mill system. The new model is with mismatched uncertainties. Then, an extended state observer (ESO is developed to estimate uncertainties. In the general high-order systems, the ESO is also used to estimate states. By dynamic surface control method, we design the controller to guarantee stabilization of the cold rolling mill system. Furthermore, we extend proposed method to general high-order systems, in which we analyze the difference from cold rolling mill system. Finally, simulation results for MAGC system are presented to demonstrate the effectiveness of the proposed control strategy.
Velinov, P.; Ruder, H.; Kostov, V.; Mateev, L.
As a continuation of our investigations of ellipsoidal Chapman Che function of the atmospheres of oblate planets Velinov et al 2004 we present new calculations for the giant planets Jupiter and Saturn and its satellite Titan In the above mentioned paper Che function only for the north and south pole regions is presented There some computations for Che function for the ionosphere of Saturn only on latitudes 90 degree at different altitudes and solar zenith angles 45 60 75 80 83 85 87 90 93 95 97 and 100 degree are made This new paper presents the results of our work on the ellipsoidal Chapman function of oblate planetary bodies Here the calculations for Che function in the oblate planet atmospheres of giant planets from Jovian group for middle and lower latitudes including the equator in Tables 1 - 3 are presented Che function for a rotational ellipsoid depends on the oblateness and on the solar zenith angle altitude latitude and the solar declination A comparison between Che function and classical Chapman function Ch for a spherical planet is made The last function is applicable for the ionospheres of terrestrial planets Venus Earth and Mars This comparison shows the necessity of introducing Che function in numerical analysis of ionospheres of Jupiter Saturn and Titan The function Che determines more precisely the optical depth parameter for solar XUV radiation and also the particle depth parameter for galactic and solar cosmic ray particles The difference between evaluations of electron production rate profiles with Che and Ch
High Latitude Mottling on Jupiter
2000-01-01
The familiar banded appearance of Jupiter at low and middle latitudes gradually gives way to a more mottled appearance at high latitudes in this striking true color image taken Dec. 13, 2000, by NASA's Cassini spacecraft.The intricate structures seen in the polar region are clouds of different chemical composition, height and thickness. Clouds are organized by winds, and the mottled appearance in the polar regions suggests more vortex-type motion and winds of less vigor at higher latitudes.The cause of this difference is not understood. One possible contributor is that the horizontal component of the Coriolis force, which arises from the planet's rotation and is responsible for curving the trajectories of ocean currents and winds on Earth, has its greatest effect at high latitudes and vanishes at the equator. This tends to create small, intense vortices at high latitudes on Jupiter. Another possibility may lie in that fact that Jupiter overall emits nearly as much of its own heat as it absorbs from the Sun, and this internal heat flux is very likely greater at the poles. This condition could lead to enhanced convection at the poles and more vortex-type structures. Further analysis of Cassini images, including analysis of sequences taken over a span of time, should help us understand the cause of equator-to-pole differences in cloud organization and evolution.By the time this picture was taken, Cassini had reached close enough to Jupiter to allow the spacecraft to return images with more detail than what's possible with the planetary camera on NASA's Earth-orbiting Hubble Space Telescope. The resolution here is 114 kilometers (71 miles) per pixel. This contrast-enhanced, edge-sharpened frame was composited from images take at different wavelengths with Cassini's narrow-angle camera, from a distance of 19 million kilometers (11.8 million miles). The spacecraft was in almost a direct line between the Sun and Jupiter, so the solar illumination on Jupiter is almost full
Hot Jupiters Aren't As Lonely As We Thought
Kohler, Susanna
2016-01-01
The Friends of Hot Jupiters (FOHJ) project is a systematic search for planetary- and stellar-mass companions in systems that have known hot Jupiters short-period, gas-giant planets. This survey has discovered that many more hot Jupiters may have companions than originally believed.Missing FriendsFOHJ was begun with the goal of better understanding the systems that host hot Jupiters, in order to settle several longstanding issues.The first problem was one of observational statistics. We know that roughly half of the Sun-like stars nearby are in binary systems, yet weve only discovered a handful of hot Jupiters around binaries. Are binary systems less likely to host hot Jupiters? Or have we just missed the binary companions in the hot-Jupiter-hosting systems weve seen so far?An additional issue relates to formation mechanisms. Hot Jupiters probably migrated inward from where they formed out beyond the ice lines in protoplanetary disks but how?This median-stacked image, obtained with adaptive optics, shows one of the newly-discovered stellar companions to a star hosting a hot Jupiter. The projected separation is ~180 AU. [Ngo et al. 2015]Observations reveal two populations of hot Jupiters: those with circular orbits aligned with their hosts spins, and those with eccentric, misaligned orbits. The former population support a migration model dominated by local planet-disk interactions, whereas the latter population suggest the hot Jupiters migrated through dynamical interactions with distant companions. A careful determination of the companion rate in hot-Jupiter-hosting systems could help establish the ability of these two models to explain the observed populations.Search for CompanionsThe FOHJ project began in 2012 and studied 51 systems hosting known, transiting hot Jupiters with roughly half on circular, aligned orbits and half on eccentric, misaligned orbits. The survey consisted of three different, complementary components:Study 1Lead author: Heather Knutson
Marriage of Electromagnetism and Gravity in an Extended Space Model and Astrophysical Phenomena
Andreev, V. A.; Tsipenyuk, D. Yu.
2013-09-01
The generalization of Einstein's special theory of relativity (SRT) is proposed. In this model the possibility of unification of scalar gravity and electromagnetism into a single unified field is considered. Formally, the generalization of the SRT is that instead of (1+3)-dimensional Minkowski space the (1+4)-dimensional extension G is considered. As a fifth additional coordinate the interval S is used. This value is saved under the usual Lorentz transformations in Minkowski space M, but it changes when the transformations in the extended space G are used. We call this model the extended space model (ESM). From a physical point of view our expansion means that processes in which the rest mass of the particles changes are acceptable now. If the rest mass of a particle does not change and the physical quantities do not depend on an additional variable S, then the electromagnetic and gravitational fields exist independently of each other. But if the rest mass is variable and there is a dependence on S, then these two fields are combined into a single unified field. In the extended space model a photon can have a nonzero mass and this mass can be either positive or negative. The gravitational effects such as the speed of escape, gravitational red shift and detection of light can be analyzed in the frame of the extended space model. In this model all these gravitational effects can be found algebraically by the rotations in the (1+4) dimensional space. Now it becomes possible to predict some future results of visible size of supermassive objects in our Universe due to new stage of experimental astronomy development in the RadioAstron Project and analyze phenomena is an explosion of the star V838 Mon.
Models of population-based analyses for data collected from large extended families.
Wang, Wenyu; Lee, Elisa T; Howard, Barbara V; Fabsitz, Richard R; Devereux, Richard B; MacCluer, Jean W; Laston, Sandra; Comuzzie, Anthony G; Shara, Nawar M; Welty, Thomas K
2010-12-01
Large studies of extended families usually collect valuable phenotypic data that may have scientific value for purposes other than testing genetic hypotheses if the families were not selected in a biased manner. These purposes include assessing population-based associations of diseases with risk factors/covariates and estimating population characteristics such as disease prevalence and incidence. Relatedness among participants however, violates the traditional assumption of independent observations in these classic analyses. The commonly used adjustment method for relatedness in population-based analyses is to use marginal models, in which clusters (families) are assumed to be independent (unrelated) with a simple and identical covariance (family) structure such as those called independent, exchangeable and unstructured covariance structures. However, using these simple covariance structures may not be optimally appropriate for outcomes collected from large extended families, and may under- or over-estimate the variances of estimators and thus lead to uncertainty in inferences. Moreover, the assumption that families are unrelated with an identical family structure in a marginal model may not be satisfied for family studies with large extended families. The aim of this paper is to propose models incorporating marginal models approaches with a covariance structure for assessing population-based associations of diseases with their risk factors/covariates and estimating population characteristics for epidemiological studies while adjusting for the complicated relatedness among outcomes (continuous/categorical, normally/non-normally distributed) collected from large extended families. We also discuss theoretical issues of the proposed models and show that the proposed models and covariance structure are appropriate for and capable of achieving the aim.
Multi-band, Multi-epoch Observations of the Transiting Warm Jupiter WASP-80b
Fukui, Akihiko; Ikoma, Masahiro; Narita, Norio; Onitsuka, Masahiro; Ita, Yoshifusa; Onozato, Hiroki; Nishiyama, Shogo; Baba, Haruka; Ryu, Tsuguru; Hirano, Teruyuki; Hori, Yasunori; Kurosaki, Kenji; Kawauchi, Kiyoe; Takahashi, Yasuhiro H; Nagayama, Takahiro; Tamura, Motohide; Kawai, Nobuyuki; Kuroda, Daisuke; Nagayama, Shogo; Ohta, Kouji; Shimizu, Yasuhiro; Yanagisawa, Kenshi; Yoshida, Michitoshi; Izumiura, Hideyuki
2014-01-01
WASP-80b is a warm Jupiter transiting a bright late-K dwarf, providing a good opportunity to extend the atmospheric study of hot Jupiters toward the lower temperature regime. We report multi-band, multi-epoch transit observations of WASP-80b by using three ground-based telescopes covering from optical (g', Rc, and Ic bands) to near infrared (NIR; J, H, and Ks bands) wavelengths. We observe five primary transits, each of which in three or four different bands simultaneously, obtaining 17 independent transit light curves. Combining them with previous works, we find that the observed transmission spectrum is largely consistent with both a solar-abundance and thick-cloud atmospheric models at 1.7-$\\sigma$ discrepancy level. On the other hand, we find a marginal spectral rise in optical region compared to NIR region at 2.9-$\\sigma$ level, which possibly indicates the existence of haze in the atmosphere. We simulate theoretical transmission spectra for a solar-abundance but hazy atmosphere, finding that a model wit...
K2 Warm Jupiters with the LCOGT TECH collaboration
Shporer, Avi; Bayliss, Daniel; Cochran, William D.; Colón, Knicole D.; Dragomir, Diana; Palle, Enric; Potter, Stephen; Siverd, Robert; LCOGT TECH Collaboration
2016-06-01
, confirming a sample of warm Jupiters transiting bright stars will support extending atmospheric characterization and spin-orbit alignment studies beyond the hot Jupiter planet class.
Modeling protein tandem mass spectrometry data with an extended linear regression strategy.
Liu, Han; Bonner, Anthony J; Emili, Andrew
2004-01-01
Tandem mass spectrometry (MS/MS) has emerged as a cornerstone of proteomics owing in part to robust spectral interpretation algorithm. The intensity patterns presented in mass spectra are useful information for identification of peptides and proteins. However, widely used algorithms can not predicate the peak intensity patterns exactly. We have developed a systematic analytical approach based on a family of extended regression models, which permits routine, large scale protein expression profile modeling. By proving an important technical result that the regression coefficient vector is just the eigenvector corresponding to the least eigenvalue of a space transformed version of the original data, this extended regression problem can be reduced to a SVD decomposition problem, thus gain the robustness and efficiency. To evaluate the performance of our model, from 60,960 spectra, we chose 2,859 with high confidence, non redundant matches as training data, based on this specific problem, we derived some measurements of goodness of fit to show that our modeling method is reasonable. The issues of overfitting and underfitting are also discussed. This extended regression strategy therefore offers an effective and efficient framework for in-depth investigation of complex mammalian proteomes.
Model-Based Engine Control Architecture with an Extended Kalman Filter
Csank, Jeffrey T.; Connolly, Joseph W.
2016-01-01
This paper discusses the design and implementation of an extended Kalman filter (EKF) for model-based engine control (MBEC). Previously proposed MBEC architectures feature an optimal tuner Kalman Filter (OTKF) to produce estimates of both unmeasured engine parameters and estimates for the health of the engine. The success of this approach relies on the accuracy of the linear model and the ability of the optimal tuner to update its tuner estimates based on only a few sensors. Advances in computer processing are making it possible to replace the piece-wise linear model, developed off-line, with an on-board nonlinear model running in real-time. This will reduce the estimation errors associated with the linearization process, and is typically referred to as an extended Kalman filter. The nonlinear extended Kalman filter approach is applied to the Commercial Modular Aero-Propulsion System Simulation 40,000 (C-MAPSS40k) and compared to the previously proposed MBEC architecture. The results show that the EKF reduces the estimation error, especially during transient operation.
Statistical model of stress corrosion cracking based on extended form of Dirichlet energy
Indian Academy of Sciences (India)
Harry Yosh
2013-12-01
The mechanism of stress corrosion cracking (SCC) has been discussed for decades. Here I propose a model of SCC reflecting the feature of fracture in brittle manner based on the variational principle under approximately supposed thermal equilibrium. In that model the functionals are expressed with extended forms of Dirichlet energy, and Dirichlet principle is applied to them to solve the variational problem that represents SCC and normal extension on pipe surface. Based on the model and the maximum entropy principle, the statistical nature of SCC colony is discussed and it is indicated that the crack has discrete energy and length under ideal isotropy of materials and thermal equilibrium.
Extending the 4I Organizational Learning Model: Information Sources, Foraging Processes and Tools
Directory of Open Access Journals (Sweden)
Tracy A. Jenkin
2013-08-01
Full Text Available The continued importance of organizational learning has recently led to several calls for further developing the theory. This article addresses these calls by extending Crossan, Lane and White’s (1999 4I model to include a fifth process, information foraging, and a fourth level, the tool. The resulting 5I organizational learning model can be generalized to a number of learning contexts, especially those that involve understanding and making sense of data and information. Given the need for organizations to both innovate and increase productivity, and the volumes of data and information that are available to support both, the 5I model addresses an important organizational issue.
Numerical modeling of concrete hydraulic fracturing with extended finite element method
Institute of Scientific and Technical Information of China (English)
REN QingWen; DONG YuWen; YU TianTang
2009-01-01
The extended finite element method (XFEM) is a new numerical method for modeling discontinuity.Research about numerical modeling for concrete hydraulic fracturing by XFEM is explored. By building the virtual work principle of the fracture problem considering water pressure on the crack surface, the governing equations of XFEM for hydraulic fracture modeling are derived. Implementation of the XFEM for hydraulic fracturing is presented. Finally, the method is verified by two examples and the advan-tages of the XFEM for hydraulic fracturing analysis are displayed.
Numerical modeling of concrete hydraulic fracturing with extended finite element method
Institute of Scientific and Technical Information of China (English)
无
2009-01-01
The extended finite element method (XFEM) is a new numerical method for modeling discontinuity. Research about numerical modeling for concrete hydraulic fracturing by XFEM is explored. By building the virtual work principle of the fracture problem considering water pressure on the crack surface, the governing equations of XFEM for hydraulic fracture modeling are derived. Implementation of the XFEM for hydraulic fracturing is presented. Finally, the method is verified by two examples and the advan- tages of the XFEM for hydraulic fracturing analysis are displayed.
A method of designing smartphone interface based on the extended user's mental model
Zhao, Wei; Li, Fengmin; Bian, Jiali; Pan, Juchen; Song, Song
2017-01-01
The user's mental model is the core guiding theory of product design, especially practical products. The essence of practical product is a tool which is used by users to meet their needs. Then, the most important feature of a tool is usability. The design method based on the user's mental model provides a series of practical and feasible theoretical guidance for improving the usability of the product according to the user's awareness of things. In this paper, we propose a method of designing smartphone interface based on the extended user's mental model according to further research on user groups. This approach achieves personalized customization of smartphone application interface and enhance application using efficiency.
Constraints on the atmospheric circulation and variability of the eccentric hot Jupiter XO-3b
Energy Technology Data Exchange (ETDEWEB)
Wong, Ian; Knutson, Heather A. [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125 (United States); Cowan, Nicolas B. [Center for Interdisciplinary Exploration and Astrophysics (CIERA), Department of Earth and Planetary Sciences, Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 (United States); Lewis, Nikole K. [Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Agol, Eric [Department of Astronomy, University of Washington, Seattle, WA 98195 (United States); Burrows, Adam [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Deming, Drake [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Fortney, Jonathan J.; Laughlin, Gregory [Department of Astronomy and Astrophysics, University of California at Santa Cruz, Santa Cruz, CA 95604 (United States); Fulton, Benjamin J. [Institute for Astronomy, University of Hawaii, Honolulu, HI 96822 (United States); Langton, Jonathan [Department of Physics, Principia College, Elsah, IL 62028 (United States); Showman, Adam P., E-mail: iwong@caltech.edu [Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721 (United States)
2014-10-20
We report secondary eclipse photometry of the hot Jupiter XO-3b in the 4.5 μm band taken with the Infrared Array Camera on the Spitzer Space Telescope. We measure individual eclipse depths and center of eclipse times for a total of 12 secondary eclipses. We fit these data simultaneously with two transits observed in the same band in order to obtain a global best-fit secondary eclipse depth of 0.1580% ± 0.0036% and a center of eclipse phase of 0.67004 ± 0.00013. We assess the relative magnitude of variations in the dayside brightness of the planet by measuring the size of the residuals during ingress and egress from fitting the combined eclipse light curve with a uniform disk model and place an upper limit of 0.05%. The new secondary eclipse observations extend the total baseline from one and a half years to nearly three years, allowing us to place an upper limit on the periastron precession rate of 2.9 × 10{sup –3} deg day{sup –1}— the tightest constraint to date on the periastron precession rate of a hot Jupiter. We use the new transit observations to calculate improved estimates for the system properties, including an updated orbital ephemeris. We also use the large number of secondary eclipses to obtain the most stringent limits to date on the orbit-to-orbit variability of an eccentric hot Jupiter and demonstrate the consistency of multiple-epoch Spitzer observations.
A fireball in Jupiter's atmosphere
Cook, A. F.; Duxbury, T. C.
1981-01-01
One fireball was photographed during two encounters with Jupiter. Its total luminosity was 120,000 0 mag s (at standard range 100 km). If the luminous efficiency proposed by Cook et al. (1981) for slip flow of a meteoroid in its own vapors is employed, an estimated mass of 11 kg is obtained. A rough absolute magnitude is -12.5. If it is noted that the search was conducted for a total of 223 s during two exposures, a number density near Jupiter of 10 to the -28th/cu cm is estimated for masses of meteoroids of 3 kg and greater. This value is about a factor of six smaller than a rough upper limit reached from an extrapolation from terrestrial observations of meteors and comets.
The effect of Jupiter oscillations on Juno gravity measurements
Durante, Daniele; Guillot, Tristan; Iess, Luciano
2017-01-01
Seismology represents a unique method to probe the interiors of giant planets. Recently, Saturn's f-modes have been indirectly observed in its rings, and there is strong evidence for the detection of Jupiter global modes by means of ground-based, spatially-resolved, velocimetry measurements. We propose to exploit Juno's extremely accurate radio science data by looking at the gravity perturbations that Jupiter's acoustic modes would produce. We evaluate the perturbation to Jupiter's gravitational field using the oscillation spectrum of a polytrope with index 1 and the corresponding radial eigenfunctions. We show that Juno will be most sensitive to the fundamental mode (n = 0), unless its amplitude is smaller than 0.5 cm/s, i.e. 100 times weaker than the n ∼ 4 - 11 modes detected by spatially-resolved velocimetry. The oscillations yield contributions to Juno's measured gravitational coefficients similar to or larger than those expected from shallow zonal winds (extending to depths less than 300 km). In the case of a strong f-mode (radial velocity ∼ 30 cm/s), these contributions would become of the same order as those expected from deep zonal winds (extending to 3000 km), especially on the low degree zonal harmonics, therefore requiring a new approach to the analysis of Juno data.
Karlsson, Ola
2012-01-01
Jupiter Trojan asteroid dynamics have been studied for a long time but it is only within the last decades that the known population has become large enough to make other studies meaningful. In four articles I have been scratching the surface of the unknown Trojan knowledge space. Paper I presents photometric observations confirming a larger variety in surface redness for the smaller Trojans compared to the larger ones, in line with the groups in the outer main asteroid belt. However, the larg...
Murthy, D N Prabhakar
2014-01-01
Serving to unify the existing literature on extended warranties, maintenance service contracts and lease contracts, this book also presents a unique perspective on the topic focussed on cost analysis and decision-making from the perspectives of the parties involved. Using a game theoretic approach together with mathematical modelling, results are presented in an integrated manner with key topics that require further research highlighted in order to serve as a starting point for researchers (engineers and statisticians) who are interested in doing further work in these areas. Designed to assist practitioners (managers, engineers, applied statisticians) who are involved with extended warranties, maintenance service contracts and lease contracts, the book provides them with the models and techniques needed for proper cost analysis and effective decision-making. The book is also suitable for use as a reference text in industrial engineering, applied statistics, operations research and management.
Nonuniform phases in the 't Hooft extended Nambu--Jona-Lasinio Model
Moreira, J; Osipov, A A; Blin, A H
2015-01-01
The phase diagram of cold dense quark matter is studied using the 't Hooft extended Nambu--Jona-Lasinio Model applied to the light quark sector with a finite current mass for the strange quark (up and down are considered in the chiral limit). By relaxing the traditional uniformity assumptions and considering a modulated light quark condensate background we investigate the possible existence of non-uniform phases in this region of the phase diagram. The effects of changes in the coupling strengths of the model are studied and it is shown that the inclusion of flavour mixing combined with the finite current mass of the strange quark catalyses the appearance of the non-uniform phases, extending the domain for their existence.
Kink antikink density wave of an extended car-following model in a cooperative driving system
Yu, Lei; Shi, Zhongke; Zhou, Bingchang
2008-12-01
We propose an extended optimal velocity model applicable to cooperative driving control system by considering the headway of arbitrary number of cars that precede and the relative velocity. The stability condition of the extended model is obtained by using the linear stability theory. The modified Korteweg-de Vries (mKdV) equation is derived to describe the traffic behavior near the critical point by applying the nonlinear analysis. Thus the traffic jams can be described by the kink-antikink density wave which is the solution of the mKdV equation. The simulation results confirm the analytical results and show that the traffic jams are suppressed more efficiently with considering not only the headway of more vehicles ahead but also the relative velocity.
GDF11 administration does not extend lifespan in a mouse model of premature aging
Freitas-Rodríguez, Sandra; Rodríguez, Francisco; Folgueras, Alicia R.
2016-01-01
GDF11 has recently emerged as a powerful anti-aging candidate, found in young blood, capable of rejuvenating a number of aged tissues, such as heart, skeletal muscle and brain. However, recent reports have shown contradictory data questioning its capacity to reverse age-related tissue dysfunction. The availability of a mouse model of accelerated aging, which shares most of the features occurring in physiological aging, gives us an excellent opportunity to test in vivo therapies aimed at extending lifespan both in pathological and normal aging. On this basis, we wondered whether the proposed anti-aging functions of GDF11 would have an overall effect on longevity. We first confirmed the existence of a reduction in GDF11/8 levels in our mouse model of accelerated aging compared with wild-type littermates. However, we show herein that GDF11 daily administration does not extend lifespan of premature-aged mice. PMID:27507054
The Kronig-Penney model extended to arbitrary potentials via numerical matrix mechanics
Pavelich, R. L.; Marsiglio, F.
2015-09-01
The Kronig-Penney model is a common starting point for studying the quantum mechanics of electrons in a confining periodic potential. This model uses a square-well potential; the energies and eigenstates can be obtained analytically for a single well, and then Bloch's theorem allows one to extend these solutions to the periodically repeating potential. In this work, we describe how to obtain simple numerical solutions for the eigenvalues and eigenstates for any confining one-dimensional potential within a unit cell and then extend this procedure, with virtually no extra effort, to the case of arbitrary periodically repeating potentials. In this way, one can study the band structure effects that arise from differently shaped potentials. One of these effects is the electron-hole mass asymmetry; more realistic unit cell potentials generally give rise to higher electron-hole mass asymmetries.
Two-Region Extended Archie's Law Model for Soil Air Permeability and Gas Diffusivity
DEFF Research Database (Denmark)
Hamamoto, Shoichiro; Møldrup, Per; Kawamoto, Ken
2011-01-01
The air permeability (ka) and soil gas diffusion coefficients (Dp) are controlling factors for gas transport and fate in variably saturated soils. We developed a unified model for ka and Dp based on the classical Archie's law, extended by: (i) allowing for two-region gas transport behavior...... for structured soils, with the natural field moisture condition (set at −100 cm H2O matric potential [pF 2]) as the reference (spliced) point between the large-pore (drained pore diameter ≥30 μm at pF ≤ 2) and the small-pore (subsequently drained pores 2) regions, and (ii) including a percolation...... threshold, set as 10% of the total porosity for structureless porous media or 10% of the porosity in the large-pore region for structured soils. The resulting extended Archie's law with reference point (EXAR) models for ka and Dp were fitted to the measured data. For both structureless and structured porous...
Crossover and thermodynamic representation in the extended η model for fractal growth
Nagatani, Takashi; Stanley, H. Eugene
1990-10-01
The η model for the dielectric breakdown is extended to the case where double power laws apply. It is shown that a crossover phenomenon between the diffusion-limited aggregation (DLA) fractal and the η fractal occurs in the extended η model. Through the use of the dimensional analysis, a dimensionless parameter is found to govern the crossover. It is shown that when η1 the inverse crossover from the η fractal to the DLA fractal appears. It is also shown that the crossover radius is controlled by changing the applied field. The global flow diagram in the two-parameter space is obtained by using a two-parameter position-space renormalization-group approach. The crossover exponent and the crossover radius are calculated. The crossover phenomenon is described in terms of a thermodynamic representation of the two-phase equilibrium.
Nonuniform phases in the ’t Hooft extended Nambu–Jona-Lasinio model
Energy Technology Data Exchange (ETDEWEB)
Moreira, J.; Hiller, B.; Blin, A. H. [Centro de Física Computacional, Departamento de Física da Universidade de Coimbra, 3004-516 Coimbra (Portugal); Osipov, A. A. [Centro de Física Computacional, Departamento de Física da Universidade de Coimbra, 3004-516 Coimbra (Portugal); on leave from Dzhelepov Laboratory of Nuclear Problems, JINR 141980 Dubna (Russian Federation)
2016-01-22
The phase diagram of cold dense quark matter is studied using the ’t Hooft extended Nambu-Jona–Lasinio Model applied to the light quark sector with a finite current mass for the strange quark (up and down are considered in the chiral limit). By relaxing the traditional uniformity assumptions and considering a modulated light quark condensate background we investigate the possible existence of non-uniform phases in this region of the phase diagram. The effects of changes in the coupling strengths of the model are studied and it is shown that the inclusion of flavour mixing combined with the finite current mass of the strange quark catalyses the appearance of the non-uniform phases, extending the domain for their existence.
The Water-Induced Linear Reduction Gas Diffusivity Model Extended to Three Pore Regions
DEFF Research Database (Denmark)
Chamindu, T. K. K. Deepagoda; de Jonge, Lis Wollesen; Kawamoto, Ken
2015-01-01
. Characterization of soil functional pore structure is an essential prerequisite to understand key gas transport processes in variably saturated soils in relation to soil ecosystems, climate, and environmental services. In this study, the water-induced linear reduction (WLR) soil gas diffusivity model originally......An existing gas diffusivity model developed originally for sieved, repacked soils was extended to characterize gas diffusion in differently structured soils and functional pore networks. A gas diffusivity-derived pore connectivity index was used as a measure of soil structure development...... developed for sieved, repacked soil was extended to two simple, linear regions to characterize gas diffusion and functional pore-network structure also in intact, structured soil systems. Based on the measurements in soils with markedly different pore regions, we showed that the two linear regions can...
Thermal Processes Governing Hot-Jupiter Radii
Spiegel, David S
2013-01-01
There have been many proposed explanations for the larger-than-expected radii of some transiting hot Jupiters, including either stellar or orbital energy deposition deep in the atmosphere or deep in the interior. In this paper, we explore the important influences on hot-Jupiter radius evolution of (i) additional heat sources in the high atmosphere, the deep atmosphere, and deep in the convective interior; (ii) consistent cooling of the deep interior through the planetary dayside, nightside, and poles; (iii) the degree of heat redistribution to the nightside; and (iv) the presence of an upper atmosphere absorber inferred to produce anomalously hot upper atmospheres and inversions in some close-in giant planets. In particular, we compare the radius expansion effects of atmospheric and deep-interior heating at the same power levels and derive the power required to achieve a given radius increase when night-side cooling is incorporated. We find that models that include consistent day/night cooling are more simila...
THE JOINT ESA-NASA EUROPA JUPITER SYSTEM MISSION (EJSM)
Lebreton, J.; Pappalardo, R. T.; Blanc, M.; Bunce, E. J.; Dougherty, M. K.; Erd, C.; Grasset, O.; Greeley, R.; Johnson, T. V.; Clark, K. B.; Prockter, L. M.; Senske, D. A.
2009-12-01
The joint "Europa Jupiter System Mission" (EJSM) is an international mission under study in collaboration between NASA and ESA. Its goal is to study Jupiter and its magnetosphere, the diversity of the Galilean satellites, the physical characteristics, composition and geology of their surfaces. Europa and Ganymede are two primary targets of the mission. The reference mission architecture consists of the NASA-led Jupiter Europa Orbiter (JEO) and the ESA-led Jupiter Ganymede Orbiter (JGO). The two primary goals of the mission are i) to determine whether the Jupiter system harbors habitable worlds and ii) to characterize the processes within the Jupiter system. The science objectives addressing the first goal are to: i) characterize and determine the extent of subsurface oceans and their relations to the deeper interior, ii) characterize the ice shells and any subsurface water, including the heterogeneity of the ice, and the nature of surface-ice-ocean exchange; iii) characterize the deep internal structure, differentiation history, and (for Ganymede) the intrinsic magnetic field; iv) compare the exospheres, plasma environments, and magnetospheric interactions; v) determine global surface composition and chemistry, especially as related to habitability; vi) understand the formation of surface features, including sites of recent or current activity, and identify and characterize candidate sites for future in situ exploration. The science objectives for addressing the second goal are to: i) understand the Jovian satellite system, especially as context for Europa and Ganymede; ii) evaluate the structure and dynamics of the Jovian atmosphere; iii) characterize processes of the Jovian magnetodisk/magnetosphere; iv) determine the interactions occurring in the Jovian system; and v) constrain models for the origin of the Jupiter system. Both spacecraft would carry a complement of 11-12 instruments launch separately in 2020 and use a Venus-Earth-Earth Gravity Assist (VEEGA
A New Software Reliability Framework——An Extended Cleanroom Model
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
Cleanroom software engineering has been proven effective in improving software development quality while at the same time increasing reliability. To adapt to large software system development, the paper presents an extended the Cleanroom model, which integrates object-oriented method based on stimulus history, reversed engineering idea, automatic testing and reliability assessment into software development. The paper discusses the architecture and realizing technology of ECM.
The dusty ballerina skirt of Jupiter
Horanyi, M.; Morfill, G.; Gruen, E.
1993-12-01
We suggest a model to explain the unexpected recurrent dust events that were observed during the Jupiter encounter by the dust detector on board the Ulysses spacecraft. This model is based dust-magnetosphere interactions. Dust particles inside the Jovian magnetosphere collect electrostatic charges and their interaction with the magnetic and electric fields can lead to energization and subsequent ejection. We discuss the dusty regions (ring/halo, `gossamer' ring) and also Io as potential sources for the Ulysses events. This model favors Io as a source. The mass and velocity range of the escaping particles are compatible with the observations, and we also suggest internal periodicities to explain the recurrent nature of the Ulysses dust events.
Secular Chaos and the Production of Hot Jupiters
Wu, Yanqin
2010-01-01
In a planetary system with two or more well-spaced, eccentric, inclined planets, secular interactions may lead to chaos. The innermost planet may gradually become very eccentric and/or inclined, as a result of the secular degrees of freedom drifting towards equipartition of angular momentum deficit. Secular chaos is known to be responsible for the eventual destabilization of Mercury in our own Solar System. Here we focus on systems with three giant planets. We characterize the secular chaos and demonstrate the criterion for it to occur, but leave a detailed understanding of secular chaos to a companion paper (Lithwick & Wu, 2010). After an extended period of eccentricity diffusion, the inner planet's pericentre can approach the star to within a few stellar radii. Strong tidal interactions and ensuing tidal dissipation extracts orbital energy from the planet and pulls it inward, creating a hot Jupiter. In contrast to other proposed channels for the production of hot Jupiters, such a scenario (which we term...
A modeling method of semiconductor fabrication flows with extended knowledge hybrid Petri nets
Institute of Scientific and Technical Information of China (English)
Zhou Binghai; Jiang Shuyu; Wang Shijin; Wu bin
2008-01-01
A modeling method of extended knowledge hybrid Petri nets (EKHPNs), incorporating object-oriented methods into hybrid Petri nets (HPNs), was presented and used for the representation and modeling of semiconductor wafer fabrication flows. To model the discrete and continuous parts of a complex semiconductor wafer fabrication flow, the HPNs were introduced into the EKHPNs. Object-oriented methods were combined into the EKHPNs for coping with the complexity of the fabrication flow. Knowledge annotations were introduced to solve input and output conflicts of the EKHPNs.Finally, to demonstrate the validity of the EKHPN method, a real semiconductor wafer fabrication case was used to illustrate the modeling procedure. The modeling results indicate that the proposed method can be used to model a complex semiconductor wafer fabrication flow expediently.
Soneson, Joshua E
2017-04-01
Wide-angle parabolic models are commonly used in geophysics and underwater acoustics but have seen little application in medical ultrasound. Here, a wide-angle model for continuous-wave high-intensity ultrasound beams is derived, which approximates the diffraction process more accurately than the commonly used Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation without increasing implementation complexity or computing time. A method for preventing the high spatial frequencies often present in source boundary conditions from corrupting the solution is presented. Simulations of shallowly focused axisymmetric beams using both the wide-angle and standard parabolic models are compared to assess the accuracy with which they model diffraction effects. The wide-angle model proposed here offers improved focusing accuracy and less error throughout the computational domain than the standard parabolic model, offering a facile method for extending the utility of existing KZK codes.
Scafetta, Nicola
2016-04-01
The Schwabe frequency band of the Zurich sunspot record since 1749 is found to be made of three major cycles with periods of about 9.98, 10.9 and 11.86 years. The two side frequencies appear to be closely related to the spring tidal period of Jupiter and Saturn (range between 9.5 and 10.5 years, and median 9.93 years) and to the tidal sidereal period of Jupiter (about 11.86 years). The central cycle can be associated to a quasi-11-year sunspot solar dynamo cycle that appears to be approximately synchronized to the average of the two planetary frequencies. A simplified harmonic constituent model based on the above two planetary tidal frequencies and on the exact dates of Jupiter and Saturn planetary tidal phases, plus a theoretically deduced 10.87-year central cycle reveals complex quasi-periodic interference/beat patterns. The major beat periods occur at about 115, 61 and 130 years, plus a quasi-millennial large beat cycle around 983 years. These frequencies and other oscillations appear once the model is non-linearly processed. We show that equivalent synchronized cycles are found in cosmogenic records used to reconstruct solar activity and in proxy climate records throughout the Holocene (last 12,000 years) up to now. The quasi-secular beat oscillations hindcast reasonably well the known prolonged periods of low solar activity during the last millennium such as the Oort, Wolf, Sporer, Maunder and Dalton minima, as well as the 17 115-year long oscillations found in a detailed temperature reconstruction of the Northern Hemisphere covering the last 2000 years. The millennial cycle hindcasts equivalent solar and climate cycles for 12,000 years. Finally, the harmonic model herein proposed reconstructs the prolonged solar minima that occurred during 1900- 1920 and 1960-1980 and the secular solar maxima around 1870-1890, 1940-1950 and 1995-2005 and a secular upward trending during the 20th century: this modulated trending agrees well with some solar proxy model, with
Micro-Doppler Effect of Extended Streamlined Targets Based on Sliding Scattering Centre Model
Directory of Open Access Journals (Sweden)
Bo Tang
2016-06-01
Full Text Available The scattering center of extended streamlined targets can slide when the direction of radiation is changed. The sliding scattering center has influence on the micro-Doppler effect of micro-motion of the extended streamlined target. This paper focused on the micro-Doppler of the extended streamlined target for the bistatic radar. Based on the analysis, the analytical expressions of the micro-Doppler of coning motion with sliding scattering center model were given for bistatic radar. And the results were validated by the simulated results of the scattering field based on the full-wave method of the electromagnetic computation. The results showed that the sliding of the scattering center can make the micro-Doppler be less and distorted, and the influence of the sliding is different for two different types of the sliding scattering centers: sliding on the surface and sliding on the bottom circle. The analytical expressions of the micro-Doppler are helpful to analyze the time-frequency presentations (TFR of the coning motion of the extended streamlined target and to estimate the parameters of the target.
Energetics of slope flows: linear and weakly nonlinear solutions of the extended Prandtl model
Güttler, Ivan; Marinović, Ivana; Večenaj, Željko; Grisogono, Branko
2016-07-01
The Prandtl model succinctly combines the 1D stationary boundary-layer dynamics and thermodynamics of simple anabatic and katabatic flows over uniformly inclined surfaces. It assumes a balance between the along-the-slope buoyancy component and adiabatic warming/cooling, and the turbulent mixing of momentum and heat. In this study, energetics of the Prandtl model is addressed in terms of the total energy (TE) concept. Furthermore, since the authors recently developed a weakly nonlinear version of the Prandtl model, the TE approach is also exercised on this extended model version, which includes an additional nonlinear term in the thermodynamic equation. Hence, interplay among diffusion, dissipation and temperature-wind interaction of the mean slope flow is further explored. The TE of the nonlinear Prandtl model is assessed in an ensemble of solutions where the Prandtl number, the slope angle and the nonlinearity parameter are perturbed. It is shown that nonlinear effects have the lowest impact on variability in the ensemble of solutions of the weakly nonlinear Prandtl model when compared to the other two governing parameters. The general behavior of the nonlinear solution is similar to the linear solution, except that the maximum of the along-the-slope wind speed in the nonlinear solution reduces for larger slopes. Also, the dominance of PE near the sloped surface, and the elevated maximum of KE in the linear and nonlinear energetics of the extended Prandtl model are found in the PASTEX-94 measurements. The corresponding level where KE>PE most likely marks the bottom of the sublayer subject to shear-driven instabilities. Finally, possible limitations of the weakly nonlinear solutions of the extended Prandtl model are raised. In linear solutions, the local storage of TE term is zero, reflecting the stationarity of solutions by definition. However, in nonlinear solutions, the diffusion, dissipation and interaction terms (where the height of the maximum interaction is
Orientation measurement based on magnetic inductance by the extended distributed multi-pole model.
Wu, Fang; Moon, Seung Ki; Son, Hungsun
2014-06-27
This paper presents a novel method to calculate magnetic inductance with a fast-computing magnetic field model referred to as the extended distributed multi-pole (eDMP) model. The concept of mutual inductance has been widely applied for position/orientation tracking systems and applications, yet it is still challenging due to the high demands in robust modeling and efficient computation in real-time applications. Recently, numerical methods have been utilized in design and analysis of magnetic fields, but this often requires heavy computation and its accuracy relies on geometric modeling and meshing that limit its usage. On the other hand, an analytical method provides simple and fast-computing solutions but is also flawed due to its difficulties in handling realistic and complex geometries such as complicated designs and boundary conditions, etc. In this paper, the extended distributed multi-pole model (eDMP) is developed to characterize a time-varying magnetic field based on an existing DMP model analyzing static magnetic fields. The method has been further exploited to compute the mutual inductance between coils at arbitrary locations and orientations. Simulation and experimental results of various configurations of the coils are presented. Comparison with the previously published data shows not only good performance in accuracy, but also effectiveness in computation.
Extended intrinsic mean spin tensor for turbulence modelling in non-inertial frame of reference
Institute of Scientific and Technical Information of China (English)
HUANG Yu-ning; MA Hui-yang
2008-01-01
We investigate the role of extended intrinsic mean spin tensor introduced in this work for turbulence modelling in a non-inertial frame of reference.It is described by the Euclidean group of transformations and,in particular,its significance and importance in the approach of the algebraic Reynolds stress modelling,such as in a nonlinear K-εmodel.To this end and for illustration of the effect of extended intrinsic spin tensor on turbulence modelling,we examine several recently developed nonlinear K-ε models and compare their performance in predicting the homogeneous turbulent shear flow in a rotating frame of reference with LES data.Our results and analysis indicate that,only if the deficiencies of these models and the like be well understood and properly corrected,may in the near future,more sophisticated nonlinear K-ε models be 0eveloped to better predict complex turbulent flows in a non-inertial frame of reference.
Laser-Plasma Modeling Using PERSEUS Extended-MHD Simulation Code for HED Plasmas
Hamlin, Nathaniel; Seyler, Charles
2016-10-01
We discuss the use of the PERSEUS extended-MHD simulation code for high-energy-density (HED) plasmas in modeling laser-plasma interactions in relativistic and nonrelativistic regimes. By formulating the fluid equations as a relaxation system in which the current is semi-implicitly time-advanced using the Generalized Ohm's Law, PERSEUS enables modeling of two-fluid phenomena in dense plasmas without the need to resolve the smallest electron length and time scales. For relativistic and nonrelativistic laser-target interactions, we have validated a cycle-averaged absorption (CAA) laser driver model against the direct approach of driving the electromagnetic fields. The CAA model refers to driving the radiation energy and flux rather than the fields, and using hyperbolic radiative transport, coupled to the plasma equations via energy source terms, to model absorption and propagation of the radiation. CAA has the advantage of not requiring adequate grid resolution of each laser wavelength, so that the system can span many wavelengths without requiring prohibitive CPU time. For several laser-target problems, we compare existing MHD results to extended-MHD results generated using PERSEUS with the CAA model, and examine effects arising from Hall physics. This work is supported by the National Nuclear Security Administration stewardship sciences academic program under Department of Energy cooperative agreements DE-FOA-0001153 and DE-NA0001836.
Modeled Arctic sea ice evolution through 2300 in CMIP5 extended RCPs
Directory of Open Access Journals (Sweden)
P. J. Hezel
2014-07-01
Full Text Available Almost all global climate models and Earth system models that participated in the Coupled Model Intercomparison Project 5 (CMIP5 show strong declines in Arctic sea ice extent and volume under the highest forcing scenario of the representative concentration pathways (RCPs through 2100, including a transition from perennial to seasonal ice cover. Extended RCP simulations through 2300 were completed for a~subset of models, and here we examine the time evolution of Arctic sea ice in these simulations. In RCP2.6, the summer Arctic sea ice extent increases compared to its minimum following the peak radiative forcing in 2044 in all nine models. RCP4.5 demonstrates continued summer Arctic sea ice decline after the forcing stabilizes due to continued warming on longer timescales. Based on the analysis of these two scenarios, we suggest that Arctic summer sea ice extent could begin to recover if and when radiative forcing from greenhouse gas concentrations were to decrease. In RCP8.5 the Arctic Ocean reaches annually ice-free conditions in seven of nine models. The ensemble of simulations completed under the extended RCPs provide insight into the global temperature increase at which sea ice disappears in the Arctic and the reversibility of declines in seasonal sea ice extent.
Energy Technology Data Exchange (ETDEWEB)
Ma, Jie; Wang, Bo [State Key Laboratory of Advanced Special Steel, Shanghai University, Shanghai 200072 (China); Shanghai Engineering Technology Research Center of Special Casting, Shanghai 201605 (China); Zhao, Shunli [Research Institute, Baoshan Iron & Steel Co., Ltd, Shanghai 201900 (China); Wu, Guangxin [State Key Laboratory of Advanced Special Steel, Shanghai University, Shanghai 200072 (China); Shanghai Engineering Technology Research Center of Special Casting, Shanghai 201605 (China); Zhang, Jieyu, E-mail: zjy6162@staff.shu.edu.cn [State Key Laboratory of Advanced Special Steel, Shanghai University, Shanghai 200072 (China); Shanghai Engineering Technology Research Center of Special Casting, Shanghai 201605 (China); Yang, Zhiliang [State Key Laboratory of Advanced Special Steel, Shanghai University, Shanghai 200072 (China); Shanghai Engineering Technology Research Center of Special Casting, Shanghai 201605 (China)
2016-05-25
We have extended the dendritic growth model first proposed by Boettinger, Coriell and Trivedi (here termed EBCT) for microstructure simulations of rapidly solidified non-dilute alloys. The temperature-dependent distribution coefficient, obtained from calculations of phase equilibria, and the continuous growth model (CGM) were adopted in the present EBCT model to describe the solute trapping behaviors. The temperature dependence of the physical properties, which were not used in previous dendritic growth models, were also considered in the present EBCT model. These extensions allow the present EBCT model to be used for microstructure simulations of non-dilute alloys. The comparison of the present EBCT model with the BCT model proves that the considerations of the distribution coefficient and physical properties are necessary for microstructure simulations, especially for small particles with high undercoolings. Finally, the EBCT model was incorporated into the cellular automaton-finite element (CAFE) model to simulate microstructures of gas-atomized ASP30 high speed steel particles that were then compared with experimental results. Both the simulated and experimental results reveal that a columnar dendritic microstructure preferentially forms in small particles and an equiaxed microstructure forms otherwise. The applications of the present EBCT model provide a convenient way to predict the microstructure of non-dilute alloys. - Highlights: • A dendritic growth model was developed considering non-equilibrium distribution coefficient. • The physical properties with temperature dependence were considered in the extended model. • The extended model can be used to non-dilute alloys and the extensions are necessary in small particles. • Microstructure of ASP30 steel was investigated using the present model and verified by experiment.
Deciphering Jupiter's atmospheric dynamics using the upcoming Juno gravity measurements
Kaspi, Yohai; Galanti, Eli
2016-07-01
This summer, the Juno spacecraft will arrive at Jupiter in course for close flybys of the planet, obtaining a high precision gravity spectrum of Jupiter. This data can be used to estimate the depth of Jupiter's observed cloud-level wind, and decipher the possible internal flows, that might be decoupled from the surface wind. In this talk, we discuss the Juno gravity experiment, and the possible outcomes with regard to the flows on Jupiter. We show several ways in which the gravity spectrum might be used to study the large scale flows: 1. measurements of the high order even harmonics which beyond J10 are dominated by the dynamics; 2. measurements of odd gravity harmonics which have no contribution from a static planet, and therefore are a pure signature of dynamics; 3. upper limits on the depth of the surface flow can be obtained by comparing low order even harmonics from dynamical models to the difference between the measured low order even harmonics and the largest possible values of a static planet; 4. direct latitudinally varying measurements of the gravity field exerted on the spacecraft. We will discuss how these methods may be applied given the expected sensitivities of the Juno gravity experiment. In addition, we present an inverse adjoint model, which allows given the gravity data, to infer the flows that produce it. This will allow, hopefully, to make significant progress in one of the longest-standing question in planetary atmospheric dynamics regarding the nature of the flows on the giant planets.
Ultra-relativistic electrons in Jupiter's radiation belts.
Bolton, S J; Janssen, M; Thorne, R; Levin, S; Klein, M; Gulkis, S; Bastian, T; Sault, R; Elachi, C; Hofstadter, M; Bunker, A; Dulk, G; Gudim, E; Hamilton, G; Johnson, W T K; Leblanc, Y; Liepack, O; McLeod, R; Roller, J; Roth, L; West, R
2002-02-28
Ground-based observations have shown that Jupiter is a two-component source of microwave radio emission: thermal atmospheric emission and synchrotron emission from energetic electrons spiralling in Jupiter's magnetic field. Later in situ measurements confirmed the existence of Jupiter's high-energy electron-radiation belts, with evidence for electrons at energies up to 20[?]MeV. Although most radiation belt models predict electrons at higher energies, adiabatic diffusion theory can account only for energies up to around 20[?]MeV. Unambiguous evidence for more energetic electrons is lacking. Here we report observations of 13.8[?]GHz synchrotron emission that confirm the presence of electrons with energies up to 50[?]MeV; the data were collected during the Cassini fly-by of Jupiter. These energetic electrons may be repeatedly accelerated through an interaction with plasma waves, which can transfer energy into the electrons. Preliminary comparison of our data with model results suggests that electrons with energies of less than 20[?]MeV are more numerous than previously believed.
2007-01-01
This beautiful image of the crescents of volcanic Io and more sedate Europa was snapped by New Horizons' color Multispectral Visual Imaging Camera (MVIC) at 10:34 UT on March 2, 2007, about two days after New Horizons made its closest approach to Jupiter. The picture was one of a handful of the Jupiter system that New Horizons took primarily for their artistic, rather than scientific value. This particular scene was suggested by space enthusiast Richard Hendricks of Austin, Texas, in response to an Internet request by New Horizons scientists for evocative, artistic imaging opportunities at Jupiter. This image was taken from a range of 4.6 million kilometers (2.8 million miles) from Io and 3.8 million kilometers (2.4 million miles) from Europa. Although the moons appear close in this view, a gulf of 790,000 kilometers (490,000 miles) separates them. The night side of Io is illuminated here by light reflected from Jupiter, which is out of the frame to the right. Europa's night side is completely dark, in contrast to Io, because that side of Europa faces away from Jupiter. Here, Io steals the show with its beautiful display of volcanic activity. Three volcanic plumes are visible. Most conspicuous is the enormous 300-kilometer (190-mile) -high plume from the Tvashtar volcano at the 11 o'clock position on Io's disk. Two much smaller plumes are barely visible: one from the volcano Prometheus, at the 9 o'clock position on the edge of Io's disk, and one from the volcano Amirani, seen between Prometheus and Tvashtar along Io's terminator (the line dividing day and night). The plumes appear blue because of the scattering of light by tiny dust particles ejected by the volcanoes, similar to the blue appearance of smoke. In addition, the contrasting red glow of hot lava can be seen at the source of the Tvashtar plume. The images are centered at 1 degree north, 60 degrees west on Io, and 0 degrees north, 149 degrees west on Europa. The color in this image was generated using
Trammell, George B; Li, Zhi-Yun
2010-01-01
(Abridged) The upper atmospheres of close-in gas giant exoplanets are subjected to intense heating/tidal forces from their parent stars. Atomic/ionized hydrogen (H) layers are sufficiently rarefied that magnetic pressure may dominate gas pressure for expected planetary magnetic field strength. We examine the magnetospheric structure using a 3D isothermal magnetohydrodynamic model that includes: a static "dead zone" near the magnetic equator containing magnetically confined gas; a "wind zone" outside the magnetic equator in which thermal pressure gradients and the magneto-centrifugal-tidal effect give rise to transonic outflow; and a region near the poles where sufficiently strong tidal forces may suppress transonic outflow. Using dipole field geometry, we estimate the size of the dead zone to be ~1-10 planetary radii for a range of parameters. To understand appropriate base conditions for the 3D isothermal model, we compute a 1D thermal model in which photoelectric heating from the stellar Lyman continuum is ...
Yang, Shan-Shan; Pang, Ji-Wei; Guo, Wan-Qian; Yang, Xiao-Yin; Wu, Zhong-Yang; Ren, Nan-Qi; Zhao, Zhi-Qing
2017-05-01
This paper presents the results of an extended ASM2 model for the modeling and calibration of the role of extracellular polymeric substances (EPS) in phosphorus (P) removal in an anaerobic-aerobic process. In this extended ASM2 model, two new components, the bound EPS (XEPS) and the soluble EPS (SEPS), are introduced. Compared with the ASM2, 7.71, 8.53, and 9.28% decreases in polyphosphate (polyP) were observed in the extended ASM2 in three sequencing batch reactors feeding with different COD/P ratios, indicating that 7.71-9.28% of P in the liquid was adsorbed by EPS. Sensitive analysis indicated that, five parameters were the significant influential parameters and had been chosen for further model calibration by using the least square method to simulate by MATLAB. This extended ASM2 has been successfully established to simulate the output variables and provides a useful reference for the mathematic simulations of the role of EPS in biological phosphorus removal process. Copyright © 2017. Published by Elsevier Ltd.
Teo, Timothy
2016-01-01
The aim of this study is to examine the factors that influenced the use of Facebook among university students. Using an extended technology acceptance model (TAM) with emotional attachment (EA) as an external variable, a sample of 498 students from a public-funded Thailand university were surveyed on their responses to five variables hypothesized…
Optimising and extending the geometrical modeller of a physics simulation framework
Urban, P
1998-01-01
The design of highly complex particle detectors used in High Energy Physics involves both CAD systems and physics simulation packages like Geant4. Geant4 is able to exchange detector geometries with CAD systems, conforming to the Standard for the Exchange of Product Model Data (STEP); Boundary Representation (B-Rep) models are transferred. Particle tracking is performed in these models, requiring efficient and accurate intersection computations from the geometrical modeller. The results of extending and optimising the modeller of Geant4 form the contents of this thesis. Swept surfaces: surfaces of linear extrusion and surfaces of revolution have been implemented. The problem of classifying points on surfaces bounded by curves as being inside or outside has been solved. These tasks necessitated the extension and optimisation of code related to curves and lead to a re-design of this code. Emphasis was put on efficiency and on dealing with numerical errors. The results will be integrated into the upcoming beta t...
Robbins, Joshua; Voth, Thomas E.
2007-12-01
The eXtended Finite Element Method (X-FEM) is a finite-element based discretization technique developed originally to model dynamic crack propagation [1]. Since that time the method has been used for modeling physics ranging from static meso-scale material failure to dendrite growth. Here we adapt the recent advances of Vitali and Benson [2] and Song et al. [3] to model dynamic loading of a polycrystalline material. We use demonstration problems to examine the method's efficacy for modeling the dynamic response of polycrystalline materials at the meso-scale. Specifically, we use the X-FEM to model grain boundaries. This approach allows us to i) eliminate ad-hoc mixture rules for multi-material elements and ii) avoid explicitly meshing grain boundaries.
Hamada, Kosuke; Kaneko, Tatsuya; Miyakoshi, Shohei; Ohta, Yukinori
2017-07-01
We comparatively study the excitonic insulator state in the extended Falicov-Kimball model (EFKM, a spinless two-band model) on the two-dimensional square lattice using the variational cluster approximation (VCA) and the cluster dynamical impurity approximation (CDIA). In the latter, the particle-bath sites are included in the reference cluster to take into account the particle-number fluctuations in the correlation sites. We thus calculate the particle-number distribution, order parameter, ground-state phase diagram, anomalous Green's function, and pair coherence length, thereby demonstrating the usefulness of the CDIA in the discussion of the excitonic condensation in the EFKM.
Luminosity variation in the extended one-zone RR Lyrae model
Directory of Open Access Journals (Sweden)
Pricopi D.
2005-01-01
Full Text Available The Stellingwerf one-zone stellar model is extended by assuming, a slow and uniform rotation that leads to a very small oblateness of the star. The matter in the core-surrounding shell is supposed to consists of a mixture of ideal gas and radiation. This one-zone stellar pulsation model is proposed as a tool to investigate the factors affecting luminosity variations of pulsating stars. Linear and nonlinear analyses of the resulting equations are described. The results are in very good agreement with the observed RR Lyrae light curves. .
Doping driven metal-insulator transitions and charge orderings in the extended Hubbard model
Kapcia, K J; Capone, M; Amaricci, A
2016-01-01
We perform a thorough study of an extended Hubbard model featuring local and nearest-neighbor Coulomb repulsion. Using dynamical mean-field theory we investigated the zero temperature phase-diagram of this model as a function of the chemical doping. The interplay between local and non-local interaction drives a variety of phase-transitions connecting two distinct charge-ordered insulators, i.e., half-filled and quarter-filled, a charge-ordered metal and a Mott insulating phase. We characterize these transitions and the relative stability of the solutions and we show that the two interactions conspire to stabilize the quarter-filled charge ordered phase.
Characteristics of QCD phase transitions in an extended Skyrme model on S$^{3}$
Kim, J H; Lee, H K; Kim, Joon Ha; Yee, Sooman; Lee, Hyun Kyu
1994-01-01
We study the characteristics of the QCD phase transitions in dense hadronic matter using the Skyrme model constructed on S^3. We find numerically the localized solutions on S^3 using the extended Skyrme model which implements correctly the scale symmetry of QCD. The transition from the localized phase to the delocalized phase is found to be of first order at the critical radius of the hypersphere, L_c. The chiral restoration and the gluon decondensation also take place at the same critical size.
The Stability Analysis for an Extended Car Following Model Based on Control Theory
Ge, Hong-Xia; Meng, Xiang-Pei; Zhu, Ke-Qiang; Cheng, Rong-Jun
2014-08-01
A new method is proposed to study the stability of the car-following model considering traffic interruption probability. The stability condition for the extended car-following model is obtained by using the Lyapunov function and the condition for no traffic jam is also given based on the control theory. Numerical simulations are conducted to demonstrate and verify the analytical results. Moreover, numerical simulations show that the traffic interruption probability has an influence on driving behavior and confirm the effectiveness of the method on the stability of traffic flow.
Standard model extended by a heavy singlet: Linear vs. nonlinear EFT
Directory of Open Access Journals (Sweden)
G. Buchalla
2017-04-01
Full Text Available We consider the Standard Model extended by a heavy scalar singlet in different regions of parameter space and construct the appropriate low-energy effective field theories up to first nontrivial order. This top-down exercise in effective field theory is meant primarily to illustrate with a simple example the systematics of the linear and nonlinear electroweak effective Lagrangians and to clarify the relation between them. We discuss power-counting aspects and the transition between both effective theories on the basis of the model, confirming in all cases the rules and procedures derived in previous works from a bottom-up approach.
Standard model extended by a heavy singlet: Linear vs. nonlinear EFT
Energy Technology Data Exchange (ETDEWEB)
Buchalla, G., E-mail: gerhard.buchalla@lmu.de; Catà, O.; Celis, A.; Krause, C.
2017-04-15
We consider the Standard Model extended by a heavy scalar singlet in different regions of parameter space and construct the appropriate low-energy effective field theories up to first nontrivial order. This top-down exercise in effective field theory is meant primarily to illustrate with a simple example the systematics of the linear and nonlinear electroweak effective Lagrangians and to clarify the relation between them. We discuss power-counting aspects and the transition between both effective theories on the basis of the model, confirming in all cases the rules and procedures derived in previous works from a bottom-up approach.
Juno at Jupiter: Mission and Science
Bolton, Scott
2016-07-01
The Juno mission is the second mission in NASA's New Frontiers program. Launched in August 2011, Juno arrives at Jupiter in July 2016. Juno science goals include the study of Jupiter's origin, interior structure, deep atmosphere, aurora and magnetosphere. Jupiter's formation is fundamental to the evolution of our solar system and to the distribution of volatiles early in the solar system's history. Juno's measurements of the abundance of Oxygen and Nitrogen in Jupiter's atmosphere, and the detailed maps of Jupiter's gravity and magnetic field structure will constrain theories of early planetary development. Juno's orbit around Jupiter is a polar elliptical orbit with perijove approximately 5000 km above the visible cloud tops. The payload consists of a set of microwave antennas for deep sounding, magnetometers, gravity radio science, low and high energy charged particle detectors, electric and magnetic field radio and plasma wave experiment, ultraviolet imaging spectrograph, infrared imager and a visible camera. The Juno design enables the first detailed investigation of Jupiter's interior structure, and deep atmosphere as well as the first in depth exploration of Jupiter's polar magnetosphere. The Juno mission design, science goals, and measurements related to the atmosphere of Jupiter will be presented.
Validating and extending the three process model of alertness in airline operations.
Ingre, Michael; Van Leeuwen, Wessel; Klemets, Tomas; Ullvetter, Christer; Hough, Stephen; Kecklund, Göran; Karlsson, David; Åkerstedt, Torbjörn
2014-01-01
Sleepiness and fatigue are important risk factors in the transport sector and bio-mathematical sleepiness, sleep and fatigue modeling is increasingly becoming a valuable tool for assessing safety of work schedules and rosters in Fatigue Risk Management Systems (FRMS). The present study sought to validate the inner workings of one such model, Three Process Model (TPM), on aircrews and extend the model with functions to model jetlag and to directly assess the risk of any sleepiness level in any shift schedule or roster with and without knowledge of sleep timings. We collected sleep and sleepiness data from 136 aircrews in a real life situation by means of an application running on a handheld touch screen computer device (iPhone, iPod or iPad) and used the TPM to predict sleepiness with varying level of complexity of model equations and data. The results based on multilevel linear and non-linear mixed effects models showed that the TPM predictions correlated with observed ratings of sleepiness, but explorative analyses suggest that the default model can be improved and reduced to include only two-processes (S+C), with adjusted phases of the circadian process based on a single question of circadian type. We also extended the model with a function to model jetlag acclimatization and with estimates of individual differences including reference limits accounting for 50%, 75% and 90% of the population as well as functions for predicting the probability of any level of sleepiness for ecological assessment of absolute and relative risk of sleepiness in shift systems for safety applications.
Validating and extending the three process model of alertness in airline operations.
Directory of Open Access Journals (Sweden)
Michael Ingre
Full Text Available Sleepiness and fatigue are important risk factors in the transport sector and bio-mathematical sleepiness, sleep and fatigue modeling is increasingly becoming a valuable tool for assessing safety of work schedules and rosters in Fatigue Risk Management Systems (FRMS. The present study sought to validate the inner workings of one such model, Three Process Model (TPM, on aircrews and extend the model with functions to model jetlag and to directly assess the risk of any sleepiness level in any shift schedule or roster with and without knowledge of sleep timings. We collected sleep and sleepiness data from 136 aircrews in a real life situation by means of an application running on a handheld touch screen computer device (iPhone, iPod or iPad and used the TPM to predict sleepiness with varying level of complexity of model equations and data. The results based on multilevel linear and non-linear mixed effects models showed that the TPM predictions correlated with observed ratings of sleepiness, but explorative analyses suggest that the default model can be improved and reduced to include only two-processes (S+C, with adjusted phases of the circadian process based on a single question of circadian type. We also extended the model with a function to model jetlag acclimatization and with estimates of individual differences including reference limits accounting for 50%, 75% and 90% of the population as well as functions for predicting the probability of any level of sleepiness for ecological assessment of absolute and relative risk of sleepiness in shift systems for safety applications.
Schmettow, Martin; Schnittker, Raphaela; Schraagen, Jan Maarten
2017-03-21
This paper proposes and demonstrates an extended protocol for usability validation testing of medical devices. A review of currently used methods for the usability evaluation of medical devices revealed two main shortcomings. Firstly, the lack of methods to closely trace the interaction sequences and derive performance measures. Secondly, a prevailing focus on cross-sectional validation studies, ignoring the issues of learnability and training. The U.S. Federal Drug and Food Administration's recent proposal for a validation testing protocol for medical devices is then extended to address these shortcomings: (1) a novel process measure 'normative path deviations' is introduced that is useful for both quantitative and qualitative usability studies and (2) a longitudinal, completely within-subject study design is presented that assesses learnability, training effects and allows analysis of diversity of users. A reference regression model is introduced to analyze data from this and similar studies, drawing upon generalized linear mixed-effects models and a Bayesian estimation approach. The extended protocol is implemented and demonstrated in a study comparing a novel syringe infusion pump prototype to an existing design with a sample of 25 healthcare professionals. Strong performance differences between designs were observed with a variety of usability measures, as well as varying training-on-the-job effects. We discuss our findings with regard to validation testing guidelines, reflect on the extensions and discuss the perspectives they add to the validation process.
Song, Rui; Lei, Chengmin; Han, Kai; Chen, Zilun; Pu, Dongsheng; Hou, Jing
2017-05-01
Supercontinuum generation directly from a nonlinear fiber amplifier, especially from a nonlinear ytterbium-doped fiber amplifier, attracts more and more attention due to its all-fiber structure, high optical to optical conversion efficiency, and high power output potential. However, the modeling of supercontinuum generation from a nonlinear fiber amplifier has been rarely reported. In this paper, the modeling of a tapered Ytterbium-doped fiber amplifier for visible extended to infrared supercontinuum generation is proposed based on the combination of the laser rate equations and the generalized nonlinear Schrödinger equation. Ytterbium-doped fiber amplifier generally can not generate visible extended supercontinuum due to its pumping wavelength and zero-dispersion wavelength. However, appropriate tapering and four-wave mixing makes the visible extended supercontinuum generation from an ytterbium-doped fiber amplifier possible. Tapering makes the zero-dispersion wavelength of the ytterbium-doped fiber shift to the short wavelength and minimizes the dispersion matching. Four-wave mixing plays an important role in the visible spectrum generation. The influence of pulse width and pump power on the supercontinuum generation is calculated and analyzed. The simulation results imply that it is promising and possible to fabricate a visible-to-infrared supercontinuum with low pump power and flat spectrum by using the tapered ytterbium-doped fiber amplifier scheme as long as the related parameters are well-selected.
Chen, W; Desai, D; Good, D; Crison, J; Timmins, P; Paruchuri, S; Wang, J; Ha, K
2016-08-01
A computational fluid dynamic (CFD) model was developed to predict metformin release from a hydroxypropylmethylcellulose (HPMC) matrix-based extended-release formulation that took into consideration the physical and chemical properties of the drug substance, composition, as well as size and shape of the tablet. New high dose strength (1000 mg) tablet geometry was selected based on the surface area/volume (SA/V) approach advocated by Lapidus/Lordi/Reynold to obtain the desired equivalent metformin release kinetics. Maintaining a similar SA/V ratio across all extended-release metformin hydrochloride (Met XR) tablet strengths that had different geometries provided similar simulations of dissolution behavior. Experimental dissolution profiles of three lots of high-strength tablets agreed with the simulated release kinetics. Additionally, a pharmacokinetic absorption model was developed using GastroPlus™ software and known physicochemical, pharmacokinetic, and in vitro dissolution properties of metformin to predict the clinical exposure of the new high strength (1000 mg) tablet prior to conducting a human clinical bioequivalence study. In vitro metformin release kinetics were utilized in the absorption model to predict exposures in humans for new 1000-mg Met XR tablets, and the absorption model correctly projected equivalent in vivo exposure across all dose strengths. A clinical bioequivalence study was pursued based on the combined modeling results and demonstrated equivalent exposure as predicted by the simulations.
Robbins, Joshua; Voth, Thomas
2007-06-01
The eXtended Finite Element Method (X-FEM) is a finite element based discretization technique developed originally to model dynamic crack propagation [1]. Since that time the method has been used for modeling physics ranging from static mesoscale material failure to dendrite growth. Here we adapt the recent advances of Benson et al. [2] and Belytchko et al. [3] to model shock loading of polycrystalline material. Through several demonstration problems we evaluate the method for modeling the shock response of polycrystalline materials at the mesoscale. Specifically, we use the X-FEM to model grain boundaries. This approach allows us to i) eliminate ad-hoc mixture rules for multi-material elements and ii) avoid explicitly meshing grain boundaries. ([1] N. Moes, J. Dolbow, J and T. Belytschko, 1999,``A finite element method for crack growth without remeshing,'' International Journal for Numerical Methods in Engineering, 46, 131-150. [2] E. Vitali, and D. J. Benson, 2006, ``An extended finite element formulation for contact in multi-material arbitrary Lagrangian-Eulerian calculations,'' International Journal for Numerical Methods in Engineering, 67, 1420-1444. [3] J-H Song, P. M. A. Areias and T. Belytschko, 2006, ``A method for dynamic crack and shear band propagation with phantom nodes,'' International Journal for Numerical Methods in Engineering, 67, 868-893.)
Shestakova, T P
2013-01-01
We construct Hamiltonian dynamics of the generalized spherically symmetric gravitational model in extended phase space. We start from the Faddeev - Popov effective action with gauge-fixing and ghost terms, making use of gauge conditions in differential form. It enables us to introduce missing velocities into the Lagrangian and then construct a Hamiltonian function according a usual rule which is applied for systems without constraints. The main feature of Hamiltonian dynamics in extended phase space is that it can be proved to be completely equivalent to Lagrangian dynamics derived from the effective action. The sets of Lagrangian and Hamiltonian equations are not gauge invariant in general. We demonstrate that solutions to the obtained equations include those of the gauge invariant Einstein equations, and also discuss a possible role of gauge-noninvariant terms. Then, we find a BRST invariant form of the effective action by adding terms not affecting Lagrangian equations. After all, we construct the BRST cha...
Extending comprehensive models of the Earth's magnetic field with Orsted and CHAMP data
DEFF Research Database (Denmark)
Sabaka, T.J.; Olsen, Nils; Purucker, M.E.
2004-01-01
A new model of the quiet-time, near-Earth magnetic field has been derived using a comprehensive approach, which includes not only POGO and Magsat satellite data, but also data from the Orsted and CHAMP satellites. The resulting model shows great improvement over its predecessors in terms...... of completeness of sources, time span and noise reduction in parameters. With its well separated fields and extended time domain of 1960 to mid-2002, the model is able to detect the known sequence of geomagnetic jerks within this frame and gives evidence for an event of interest around 1997. Because all sources...... are coestimated in a comprehensive approach, intriguing north-south features typically filtered out with other methods are being discovered in the lithospheric representation of the model, such as the S Atlantic spreading ridge and Andean subduction zone lineations. In addition, this lithospheric field exhibits...
Institute of Scientific and Technical Information of China (English)
JIN Zhi-jian; WANG Feng-hua; ZHU Zi-shu
2007-01-01
Electric arc furnaces (EAFs) represent one of the most disturbing loads in the subtransmission or transmission electric power systems. Therefore, it is necessary to build a practical model to descript the behavior of EAF in the simulation of power system for power quality issues. This paper deals with the modeling of EAF based on the combination of extended Kalman filter to identify the parameter of arc current and the power balance equation to obtain the dynamic, multi-valued u-i characteristics of EAF load. The whole EAF systems are simulated by means of power system blockset in Matlab to validate the proposed EAF model. This model can also be used to assess the impact of the new plant or highly varying nonlinear loads that exhibit chaos in power systems.
Low-dose rapamycin extends lifespan in a mouse model of mtDNA depletion syndrome.
Siegmund, Stephanie; Yang, Hua; Sharma, Rohit; Javors, Martin; Skinner, Owen; Mootha, Vamsi; Hirano, Michio; Schon, Eric A
2017-09-01
Mitochondrial disorders affecting oxidative phosphorylation (OxPhos) are caused by mutations in both the nuclear and mitochondrial genomes. One promising candidate for treatment is the drug rapamycin, which has been shown to extend lifespan in multiple animal models, and which was previously shown to ameliorate mitochondrial disease in a knock-out mouse model lacking a nuclear-encoded gene specifying an OxPhos structural subunit (Ndufs4). In that model, relatively high-dose intraperitoneal rapamycin extended lifespan and improved markers of neurological disease, via an unknown mechanism. Here, we administered low-dose oral rapamycin to a knock-in (KI) mouse model of authentic mtDNA disease, specifically, progressive mtDNA depletion syndrome, resulting from a mutation in the mitochondrial nucleotide salvage enzyme thymidine kinase 2 (TK2). Importantly, low-dose oral rapamycin was sufficient to extend Tk2KI/KI mouse lifespan significantly, and did so in the absence of detectable improvements in mitochondrial dysfunction. We found no evidence that rapamycin increased survival by acting through canonical pathways, including mitochondrial autophagy. However, transcriptomics and metabolomics analyses uncovered systemic metabolic changes pointing to a potential "rapamycin metabolic signature." These changes also implied that rapamycin may have enabled the Tk2KI/KI mice to utilize alternative energy reserves, and possibly triggered indirect signaling events that modified mortality through developmental reprogramming. From a therapeutic standpoint, our results support the possibility that low-dose rapamycin, while not targeting the underlying mtDNA defect, could represent a crucial therapy for the treatment of mtDNA-driven, and some nuclear DNA-driven, mitochondrial diseases. © The Author 2017. Published by Oxford University Press.
Rotating magnetospheres: transport compared at Jupiter and Saturn
Kivelson, M. G.; Southwood, D. J.; Dougherty, M. K.
The magnetospheres of Jupiter and Saturn are dominated by the effects of rotation and the associated outward stress exerted by heavy ions picked up near the inner moons Fields and particle measurements in both systems show dramatic signatures of rotational periodicity At Jupiter the periodicity results principally from the effects of dipole tilt and the related displacements of the equatorial plasma sheet At Saturn there is little dipole tilt yet field and plasma properties vary periodically Efforts to understand how Saturn s rotational motion can be converted into what appears to be radial motion a conversion from rotation to rocking or reciprocating motion that is imposed in mechanical systems by a camshaft have recently focused on convective patterns with preferred sectors for transport see Southwood et al this session It is possible that similar effects are present at Jupiter and can account for plasma properties that have been described in terms of what has been referred to as the magnetic anomaly model Hill Goertz and Dessler 1983 This talk will use magnetometer data for the two systems to identify the possibly subtle signatures of the camshaft effect at Jupiter
EJSM Radar instruments: Natural radio noise from Jupiter
Cecconi, Baptiste; Hess, Sébastien; Zarka, Philippe; Blankenship, Donald; Bruzzone, Lorenzo; Santos-Costa, Daniel; Bougeret, Jean-Louis
2010-05-01
Radar instruments are part of the core payload of the Europa Jupiter System Mission (EJSM) spacecraft: NASA- led JEO (Jupiter Europa Orbiter) and ESA-led JGO (Jupiter Ganymede Orbiter). At this point of the project, several frequency bands are foreseen for radar studies between 5MHz and 50MHz. While the high frequencies (40 to 50 MHz) are clean bands since natural jovian radio emissions show a high frequency cutoff at about 40 MHz, lower frequencies are right in the middle of the intense decametric (DAM) radio emissions. We present a review of spectral intensity, variability and sources of these radio emissions. As the radio emission are beamed, it is possible to model the visibility of the radio emissions, as seen from the vicinity of Europa or Ganymede. We have investigated Io-related radio emissions as well as radio emissions related to the auroral oval. One result from these simulations is that some portion of the orbit of Europa is clean from Non-Io DAM emissions above 22 MHz. We also review the radiation belts synchrotron emission characteristics. This study clearly shows that a deep understanding of the natural radio emissions at Jupiter is necessary to prepare the future EJSM radar instrumentation.
Renormalization group running of fermion observables in an extended non-supersymmetric SO(10) model
Meloni, Davide; Ohlsson, Tommy; Riad, Stella
2017-03-01
We investigate the renormalization group evolution of fermion masses, mixings and quartic scalar Higgs self-couplings in an extended non-supersymmetric SO(10) model, where the Higgs sector contains the 10 H, 120 H, and 126 H representations. The group SO(10) is spontaneously broken at the GUT scale to the Pati-Salam group and subsequently to the Standard Model (SM) at an intermediate scale M I. We explicitly take into account the effects of the change of gauge groups in the evolution. In particular, we derive the renormalization group equations for the different Yukawa couplings. We find that the computed physical fermion observables can be successfully matched to the experimental measured values at the electroweak scale. Using the same Yukawa couplings at the GUT scale, the measured values of the fermion observables cannot be reproduced with a SM-like evolution, leading to differences in the numerical values up to around 80%. Furthermore, a similar evolution can be performed for a minimal SO(10) model, where the Higgs sector consists of the 10 H and 126 H representations only, showing an equally good potential to describe the low-energy fermion observables. Finally, for both the extended and the minimal SO(10) models, we present predictions for the three Dirac and Majorana CP-violating phases as well as three effective neutrino mass parameters.
An Extended Expectation-Confirmation Model for Mobile Nursing Information System Continuance.
Hsieh, Pi-Jung; Lai, Hui-Min; Ma, Chen-Chung; Alexander, Judith W; Lin, Memg-Yi
2016-11-01
Nursing is critical in health care systems and comprises the planning, execution, and documentation of nursing care. To better manage health care information during patient care, the use of a mobile nursing information system (MNIS) provides more time to care for inpatients by reducing time-consuming and redundant paperwork. The purpose of this study was to extend the expectation-confirmation model and explore the roles of nursing professional competency (skill in use), habit (customary use), satisfaction (with use), and frequency of prior use in the context of MNIS continuance usage. We randomly chose 3 hospitals from among 14 hospitals in Taiwan that had indicated they used an MNIS. We conducted a field survey of nurses who had experience using the MNIS. We used a valid sample of 90 nurses to test the research model, using structural equation modeling with the partial least squares method. The results show that habit and frequency of prior use had a significant impact on MNIS continuance usage. Satisfaction and frequency of prior use had a significant impact on habit. Nurses' professional competence is crucial to perceived usefulness and, thus, is relevant in the context of MNIS continuance usage. When habit weakens over time, the continuance intention predicts continuance usage. This study showed that the extended expectation-confirmation model effectively predicts nurses' MNIS continuance usage and provides implications. Academics and practitioners should understand how nurses' habits form and how they affect continued MNIS use. Understanding the antecedents of habits can help nursing managers identify and manipulate habit formation.
Directory of Open Access Journals (Sweden)
Fadare Oluwaseun Gbenga
2013-12-01
Full Text Available This paper examines various constructs of an extended TAM, Technology Acceptance Model, that are theoretically influencing the adoption and acceptability of mobile learning among 3G enabled mobile users. Mobile learning activity- based, used for this study were drawn from behaviourist and “learning and teaching support” educational paradigms. An online and manual survey instruments were used to gather data. The structural equation modelling techniques were then employed to explain the adoption processes of hypothesized research model. A theoretical model ETAM is developed based on TAM. Our result proved that psychometric constructs of TAM can be extended and that ETAM is well suited, and of good pedagogical tool in understanding mobile learning among 3G enabled handheld devices in southwest part of Nigeria. Cognitive constructs, attitude toward m-learning, self-efficacy play significant roles in influencing behavioural intention for mobile learning, of which self-efficacy is the most importance construct. Implications of results and directions for future research are discussed.
Directory of Open Access Journals (Sweden)
Wenjun Huang
2017-01-01
Full Text Available Mechanical extending limit in horizontal drilling means the maximum horizontal extending length of a horizontal well under certain ground and down-hole mechanical constraint conditions. Around this concept, the constrained optimization model of mechanical extending limits is built and simplified analytical results for pick-up and slack-off operations are deduced. The horizontal extending limits for kinds of tubular strings under different drilling parameters are calculated and drawn. To improve extending limits, an optimal design model of drill strings is built and applied to a case study. The results indicate that horizontal extending limits are underestimated a lot when the effects of friction force on critical helical buckling loads are neglected. Horizontal extending limits firstly increase and tend to stable values with vertical depths. Horizontal extending limits increase faster but finally become smaller with the increase of horizontal pushing forces for tubular strings of smaller modulus-weight ratio. Sliding slack-off is the main limit operation and high axial friction is the main constraint factor constraining horizontal extending limits. A sophisticated installation of multiple tubular strings can greatly inhibit helical buckling and increase horizontal extending limits. The optimal design model is called only once to obtain design results, which greatly increases the calculation efficiency.
The EJSM Jupiter-Ganymede Orbiter
Blanc, M.; Lebreton, J.-P.; Stankov, A.; Greeley, R.; Pappalardo, R. T.; Fujimoto, M.
2008-09-01
The Europa-Jupiter System Mission (EJSM), currently subject of a joint study by NASA, ESA and JAXA, would combine a fleet of three satellites in order to investigate in depth many questions related to the Jupiter System. These investigations are essential for our understanding of the emergence and evolution of habitable worlds, not only within the Solar System, but also for extrasolar planet investigations. Scientific targets of EJSM focus on Europa and Ganymede as a key pair of Galilean satellites, to address the questions on their habitability, formation, and internal structure, as well as the coupling with the whole Jovian system: Jupiter's atmosphere and interior, magnetosphere and magnetodisk.. In combination with a Jupiter Europa Orbiter (JEO that would be provided by NASA) and a Jupiter Magnetospheric Orbiter (JMO that would be provided by JAXA), ESA is studying a Jupiter Ganymede Orbiter (JGO). The mission scenario includes a launch in 2020 with a transfer time to Jupiter of ~6 years. After the orbit insertion around Jupiter, a first phase (~2 years) will be devoted to Jupiter system and Callisto studies, with multiple flybys of Callisto planned at low altitude (~200 km), followed by a Ganymede orbit insertion and extensive study of Ganymede (~1 year). In depth comparative study of inner (Io and Europe) and outer (Ganymede and Callisto) satellites with combined payload of JEO and JGO will address the question of the geologic relative evolution of the satellites. On JGO, the transport phenomena in the magnetosphere of Jupiter will be studied in combination with JMO, and the Ganymede magnetosphere will be observed in situ. Jupiter atmosphere investigations on JGO will focus on coupling phenomena between troposphere, stratosphere and mesosphere, the stratospheric composition and the question of thermospheric heating.
Jupiter - Friend or Foe? IV: The influence of orbital eccentricity and inclination
Horner, J
2011-01-01
For many years, it was assumed that Jupiter prevented the Earth from being subject to a punishing impact regime that would greatly hinder the development of life. Here, we present the 4th in a series of studies investigating this hypothesis. Previously, we examined the effect of Jupiter's mass on the impact rate experienced by Earth. Here, we extend that approach to consider the influence of Jupiter's orbital eccentricity and inclination on the impact rate. We first consider scenarios in which Jupiter's orbital eccentricity was somewhat higher and somewhat lower than that in our Solar System. We find that Jupiter's orbital eccentricity plays a moderate role in determining the impact flux at Earth, with more eccentric orbits resulting in a higher impact rate of asteroids than for more circular orbits. This is particularly pronounced at high "Jupiter" masses. For short-period comets, the same effect is clearly apparent, albeit to a lesser degree. The flux of short-period comets impacting the Earth is slightly h...
A hot Jupiter orbiting a 2-Myr-old solar-mass T Tauri star
Donati, JF; Malo, L; Baruteau, C; Yu, L; Hebrard, E; Hussain, G; Alencar, S; Menard, F; Bouvier, J; Petit, P; Takami, M; Doyon, R; Cameron, A Collier
2016-01-01
Hot Jupiters are giant Jupiter-like exoplanets that orbit 100x closer to their host stars than Jupiter does to the Sun. These planets presumably form in the outer part of the primordial disc from which both the central star and surrounding planets are born, then migrate inwards and yet avoid falling into their host star. It is however unclear whether this occurs early in the lives of hot Jupiters, when still embedded within protoplanetary discs, or later, once multiple planets are formed and interact. Although numerous hot Jupiters were detected around mature Sun-like stars, their existence has not yet been firmly demonstrated for young stars, whose magnetic activity is so intense that it overshadows the radial velocity signal that close-in giant planets can induce. Here we show that hot Jupiters around young stars can be revealed from extended sets of high-resolution spectra. Once filtered-out from the activity, radial velocities of V830 Tau derived from new data collected in late 2015 exhibit a sine wave of...
An Extended Model Driven Framework for End-to-End Consistent Model Transformation
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Mr. G. Ramesh
2016-08-01
Full Text Available Model Driven Development (MDD results in quick transformation from models to corresponding systems. Forward engineering features of modelling tools can help in generating source code from models. To build a robust system it is important to have consistency checking in the design models and the same between design model and the transformed implementation. Our framework named as Extensible Real Time Software Design Inconsistency Checker (XRTSDIC proposed in our previous papers supports consistency checking in design models. This paper focuses on automatic model transformation. An algorithm and defined transformation rules for model transformation from UML class diagram to ERD and SQL are being proposed. The model transformation bestows many advantages such as reducing cost of development, improving quality, enhancing productivity and leveraging customer satisfaction. Proposed framework has been enhanced to ensure that the transformed implementations conform to their model counterparts besides checking end-to-end consistency.
Evidence for Two Hot-Jupiter Formation Paths
Nelson, Benjamin E.; Ford, Eric B.; Rasio, Frederic A.
2017-09-01
Disk migration and high-eccentricity migration are two well-studied theories to explain the formation of hot Jupiters. The former predicts that these planets can migrate up until the planet-star Roche separation ({a}{Roche}) and the latter predicts they will tidally circularize at a minimum distance of 2 {a}{Roche}. Considering long-running radial velocity and transit surveys have identified a couple hundred hot Jupiters to date, we can revisit the classic question of hot-Jupiter formation in a data-driven manner. We approach this problem using data from several exoplanet surveys (radial velocity, Kepler, HAT, and WASP) allowing for either a single population or a mixture of populations associated with these formation channels, and applying a hierarchical Bayesian mixture model of truncated power laws of the form {x}γ -1 to constrain the population-level parameters of interest (e.g., location of inner edges, γ, mixture fractions). Within the limitations of our chosen models, we find that the current radial velocity and Kepler sample of hot Jupiters can be well explained with a single truncated power-law distribution with a lower cutoff near 2 {a}{Roche}, a result that still holds after a decade, and γ =-0.51{+/- }0.200.19. However, the HAT and WASP data show evidence for multiple populations (Bayes factor ≈ {10}21). We find that 15{+/- }69 % reside in a component consistent with disk migration (γ =-0.04{+/- }1.270.53) and 85{+/- }96 % in one consistent with high-eccentricity migration (γ =-1.38{+/- }0.470.32). We find no immediately strong connections with some observed host star properties and speculate on how future exoplanet surveys could improve upon hot-Jupiter population inference.
Nucleon scattering on actinides using a dispersive optical model with extended couplings
SoukhovitskiÄ©, E. Sh.; Capote, R.; Quesada, J. M.; Chiba, S.; Martyanov, D. S.
2016-12-01
The Tamura coupling model [Rev. Mod. Phys. 37, 679 (1965), 10.1103/RevModPhys.37.679] has been extended to consider the coupling of additional low-lying rotational bands to the ground-state band. Rotational bands are built on vibrational bandheads (even-even targets) or single-particle bandheads (odd-A targets) including both axial and nonaxial deformations. These additional excitations are introduced as a perturbation to the underlying axially symmetric rigid-rotor structure of the ground-state rotational band. Coupling matrix elements of the generalized optical model are derived for extended multiband transitions in even-even and odd-A nuclei. Isospin symmetric formulation of the optical model is employed. A coupled-channels optical-model potential (OMP) containing a dispersive contribution is used to fit simultaneously all available optical experimental databases including neutron strength functions for nucleon scattering on 232Th,233,235,238U, and 239Pu nuclei. Quasielastic (p ,n ) scattering data on 232Th and 238U to the isobaric analog states of the target nucleus are also used to constrain the isovector part of the optical potential. Lane consistent OMP is derived for all actinides if corresponding multiband coupling schemes are defined. For even-even (odd-A ) actinides almost all low-lying collective levels below 1 MeV (0.5 MeV) of excitation energy are coupled. OMP parameters show a smooth energy dependence and energy-independent geometry. A phenomenological optical-model potential that couples multiple bands in odd-A actinides is published for a first time. Calculations using the derived OMP potential reproduce measured total cross-section differences between several actinide pairs within experimental uncertainty for incident neutron energies from 50 keV up to 150 MeV. The importance of extended coupling is studied. Multiband coupling is stronger in even-even targets owing to the collective nature of the coupling; the impact of extended coupling on
MILES extended: Stellar population synthesis models from the optical to the infrared
Röck, B.; Vazdekis, A.; Ricciardelli, E.; Peletier, R. F.; Knapen, J. H.; Falcón-Barroso, J.
2016-05-01
We present the first single-burst stellar population models, which covers the optical and the infrared wavelength range between 3500 and 50 000 Å and which are exclusively based on empirical stellar spectra. To obtain these joint models, we combined the extended MILES models in the optical with our new infrared models that are based on the IRTF (Infrared Telescope Facility) library. The latter are available only for a limited range in terms of both age and metallicity. Our combined single-burst stellar population models were calculated for ages larger than 1 Gyr, for metallicities between [ Fe / H ] = - 0.40 and 0.26, for initial mass functions of various types and slopes, and on the basis of two different sets of isochrones. They are available to the scientific community on the MILES web page. We checked the internal consistency of our models and compared their colour predictions to those of other models that are available in the literature. Optical and near infrared colours that are measured from our models are found to reproduce the colours well that were observed for various samples of early-type galaxies. Our models will enable a detailed analysis of the stellar populations of observed galaxies.
A 3-Factor Model Relating Communication to Risk Mitigation of Extended Information System Failover
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Athanasios Podaras
2015-06-01
Full Text Available This paper aims to analyse the relation between timely and effective communication and risk mitigation of late recovery after an unexpected information system outage in enterprises. An unforeseen information system failure in modern enterprise units, may result to significant operational and financial damage. In such a critical incident, effective communication between the team leaders and the recovery team involved, can minimize or even eliminate this negative impact. An extended information system outage can be perceived as a time deviation from the Maximum Accepted Outage (ΜΑΟ timeframe, proposed by the business continuity management, according to the value of which dependent business functions may be interrupted without any serious effects to the company. The paper examines the relation between 3 basic factors and the efficient communication between team members. The factors are: timely information distribution, staff availability and network availability. Through the current paper, the author proposes a risk analysis model, based on the Composite Risk Index theory of Risk Management, which can significantly diminish the possibility of an extended information system outage, as well as calculate the extended time required to recover a system when the aforementioned factors emerge in their worst form. The precise calculation of recovery time can be achieved via the execution of business continuity tests which include scenarios, according to which an unexpected system outage coexists with delayed information distribution as well as low staff and network availability.
Evaluation of the Extended CBD Model: A Case Study using IMS Application
Directory of Open Access Journals (Sweden)
M. Rizwan Jameel Qureshi
2013-06-01
Full Text Available A large number of projects failed because of concentrating on developing new software. The Main drawbacks of new software development are more costly, and need maintenance. Reuse is solution of these problems that caused the widespread usage of object oriented (OO development. Object oriented development is the backbone of component-based development (CBD. CBD facilitates reuse of the existing components (by customizing with the new ones. Main advantages of reusable components are more reliable, saved time and reduced cost. CBD approach is different from traditional/new software development. Several models have been proposed for traditional software development such as Waterfall, Rapid Application Development (RAD, Evolutionary, Rational Unified Process (RUP and agile. Whereas the popular CBD models, for customized development, are V, Y, Umbrella and W. Almost all software development companies, both the new software and customized software have to be developed. Therefore majority of the software development companies face problem to select and implement an appropriate process model for the both kinds of developments. To address this problem, the existing RUP and CBD models do work to some extent but the authors intend to propose an extended CBD model that it equally offers its benefits for new and customized developments. The experimental data is taken from a case study to develop IP Multimedia Sub System (IMS-based examination application using iPhone to evaluate the proposed model. The results provide evidence that the extended CBD model can be equally beneficial for the development of both new and customization components for IMS-based applications.
Mechanisms affecting the composition of Hot Jupiters atmospheres
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Showman Adam P.
2013-04-01
Full Text Available Opacities and thus local chemical composition play a key role when characterizing exoplanet atmospheres from observations. When the gas is in chemical equilibrium the chemical abundances depend strongly on the temperature profile. Grey models tend to overestimate the temperatures in the upper atmosphere. We present a new analytical model with a more realistic description of the radiative cooling in the infrared. Mechanisms like quenching and cold traps can drive the upper atmosphere far from its chemical equilibrium. The efficiency of these mechanisms depends on the strength of the vertical mixing. Using 3D global circulation models of HD209458b including passive tracers, we show that, although Hot Jupiter atmospheres are stably stratified, they are strongly mixed by planetary scale circulation patterns. We provide a rough estimate of the effective vertical mixing coefficient in Hot Jupiter atmosphere which can be used in 1D models.
Marriage of Electromagnetism and Gravity in Extended Space Model and Astrophysical Phenomena
Andreev, V A
2013-01-01
The generalization of Einstein's special theory of relativity (SRT) is proposed. In this model the possibility of unification of scalar gravity and electromagnetism into a single united field is considered. Formally, the generalization of the SRT is that instead of (1+3)-dimensional Minkowski space the (1+4)-dimensional extension G is considered. As a fifth additional coordinate the interval S is used. This value is saved under the usual Lorentz transformations in Minkowski space M, but it changes when the transformations in the extended space G are used. We call this model the extended space model (ESM). From a physical point of view our expansion means that processes in which the rest mass of the particles changes are acceptable now. If the rest mass of a particle does not change and the physical quantities do not depend on an additional variable S, then the electromagnetic and gravitational fields exist independently of each other. But if the rest mass is variable and there is a dependence on S, then these...
Ab initio derivation of multi-orbital extended Hubbard model for molecular crystals
Tsuchiizu, Masahisa; Omori, Yukiko; Suzumura, Yoshikazu; Bonnet, Marie-Laure; Robert, Vincent
2012-01-01
From configuration interaction (CI) ab initio calculations, we derive an effective two-orbital extended Hubbard model based on the gerade (g) and ungerade (u) molecular orbitals (MOs) of the charge-transfer molecular conductor (TTM-TTP)I3 and the single-component molecular conductor [Au(tmdt)2]. First, by focusing on the isolated molecule, we determine the parameters for the model Hamiltonian so as to reproduce the CI Hamiltonian matrix. Next, we extend the analysis to two neighboring molecule pairs in the crystal and we perform similar calculations to evaluate the inter-molecular interactions. From the resulting tight-binding parameters, we analyze the band structure to confirm that two bands overlap and mix in together, supporting the multi-band feature. Furthermore, using a fragment decomposition, we derive the effective model based on the fragment MOs and show that the staking TTM-TTP molecules can be described by the zig-zag two-leg ladder with the inter-molecular transfer integral being larger than the intra-fragment transfer integral within the molecule. The inter-site interactions between the fragments follow a Coulomb law, supporting the fragment decomposition strategy.
Integrable, molecular-type solutions of the extended Skyrme-Faddeev model
Sawado, Nobuyuki
2013-01-01
We construct molecular type vortex solutions in the integrable sector of the extended Skyrme-Faddeev (ESF) model.The solutions are a holomorphic type which satisfies the zero curvature condition.For some constrained values of the coupling constants, special vortex solutions exist.For other values, special forms of the potential are employed for the stability of the molecular type solution.The solutions satisfy the zero curvature condition, and then they necessarily have an infinite number of conserved current. We numerically check their existence in terms of the simulated annealing method.
Falicov-Kimball model extended by pair hopping of d-electrons
Ghosh, N. K.; Mukherjee, P.
2016-05-01
The effect of the pair hopping of d-electrons has been examined in an exact diagonalization techniqueon a four-site square cluster using extended Falicov-Kimball model. This hopping interaction shifts the critical f-level energy (Ec) at which valence transition occurs. Sharp peaks are observed in the specific heat curves and pair hopping decreases the peak height indicating a reduction in the number of density of states. Antiferromagnetic ordering as well as Curie-like behavior has been observed in the spin susceptibility (χ) characteristics.
Falicov-Kimball model extended by pair hopping of d-electrons
Energy Technology Data Exchange (ETDEWEB)
Ghosh, N. K., E-mail: nkg@klyuniv.ac.in; Mukherjee, P., E-mail: piulim2008@gmail.com [Department of Physics, University of Kalyani, Kalyani-741235, West Bengal (India)
2016-05-06
The effect of the pair hopping of d-electrons has been examined in an exact diagonalization techniqueon a four-site square cluster using extended Falicov-Kimball model. This hopping interaction shifts the critical f-level energy (E{sub c}) at which valence transition occurs. Sharp peaks are observed in the specific heat curves and pair hopping decreases the peak height indicating a reduction in the number of density of states. Antiferromagnetic ordering as well as Curie-like behavior has been observed in the spin susceptibility (χ) characteristics.
Golosov, D. I.
2013-03-01
We consider a spinless extended Falicov--Kimball model at half-filling, for the case of opposite-parity bands. Within the Hartree--Fock approach, we calculate the excitation energies in the chiral phase, which is a possible mean-field solution in the presence of a hybridisation. It is shown that the chiral phase is unstable. We then briefly review the accumulated results on stability and degeneracies of the excitonic insulator phase. Based on these, we conclude that the presence of both hybridisation and narrow-band hopping is required for electronic ferroelectricity.
Pasta phases in neutron star studied with extended relativistic mean field models
Gupta, Neha
2013-01-01
To explain several properties of finite nuclei, infinite matter, and neutron stars in a unified way within the relativistic mean field models, it is important to extend them either with higher order couplings or with density-dependent couplings. These extensions are known to have strong impact in the high-density regime. Here we explore their role on the equation of state at densities lower than the saturation density of finite nuclei which govern the phase transitions associated with pasta structures in the crust of neutron stars.
Critical phenomena of nuclear matter in the extended Zimanyi-Moszkowski model
Miyazaki, K
2005-01-01
We have studied the thermodynamics of warm nuclear matter below the saturation density in the extended Zimanyi-Moszkowski model. The EOS behaves like van der Waals one and shows the liquid-gas phase transition as the other microscopic EOSs. It predicts the critical temperature T_{C}=16.36MeV that agrees well with its empirical value. We have further calculated the phase coexistence curve and obtained the critical exponents beta=0.34 and gamma=1.22, which also agree with their universal values and empirical values derived in the recent experimental efforts.
Ground states of bilayered and extended t-J-U models
Voo, Khee-Kyun
2015-09-01
The ground states of bilayered and extended t-J-U models are investigated with renormalized mean field theory. The trial wave functions are Gutzwiller projected Hartree-Fock states, and the site double occupancies are variational parameters. It is found that a spontaneous interlayer phase separation (PS) may arise in bilayers. In electron-hole doping asymmetric systems, the propensity for PS is stronger in electron doped bands. Via a PS, superconductivity can survive to lower doping densities, and antiferromagnetism in electron doped systems may survive to higher doping densities. The result is related to the superconducting cuprates.
Many-site coherence revivals in the extended Bose-Hubbard model and the Gutzwiller approximation
Energy Technology Data Exchange (ETDEWEB)
Fischer, Uwe R.; Xiong Bo [Seoul National University, Department of Physics and Astronomy, Center for Theoretical Physics, 151-747 Seoul (Korea, Republic of)
2011-12-15
We investigate the collapse and revival of first-order coherence in deep optical lattices when long-range interactions are turned on and find that the first few revival peaks are strongly attenuated already for moderate values of the nearest-neighbor interaction coupling. It is shown that the conventionally employed Gutzwiller wave function, with only on-site number dependence of the variational amplitudes, leads to incorrect predictions for the collapse and revival oscillations within the extended Bose-Hubbard model. We provide a modified variant of the Gutzwiller ansatz, reproducing the analytically calculated time dependence of first-order coherence in the limit of zero tunneling.
Chiral spin liquid in the extended Heisenberg model on the Kagome lattice
Hu, Wenjun; Zhu, Wei; Zhang, Yi; Gong, Shoushu; Becca, Federico; Sheng, Dongning; Donna Sheng Team
2015-03-01
We investigate the extended Heisenberg model on the Kagome lattice by using Gutzwiller projected fermionic states and the variational Monte Carlo technique. In particular, when both second- and third-neighbor super-exchanges are considered, we find that a gapped spin liquid described by non-trivial magnetic fluxes and long-range chiral-chiral correlations is energetically favored compared to the gapless U(1) Dirac state. Furthermore, the topological Chern number, obtained by integrating the Berry curvature, and the degeneracy of the ground state, by constructing linearly independent states, lead us to identify this flux state as the chiral spin liquid with C = 1 / 2 fractionalized Chern number.
Energy Technology Data Exchange (ETDEWEB)
Cuta, Judith M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Suffield, Sarah R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fort, James A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Adkins, Harold E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
2013-08-15
The work reported here is an investigation of the sensitivity of component temperatures of a storage system, including fuel cladding temperatures, in response to age-related changes that could degrade the design-basis thermal behavior of the system. The purpose of these sensitivity studies is to provide a realistic example of how changes in the physical properties or configuration of the storage system components can affect temperatures and temperature distributions. The magnitudes of these sensitivities can provide guidance for identifying appropriate modeling assumptions for thermal evaluations extending long term storage out beyond 50, 100, 200, and 300 years.
White, Ronald J.; Leonard, Joel I.; Srinivasan, R. Srini; Charles, John B.
1991-01-01
The purpose of NASA's Extended Duration Orbiter program is a gradual extension of the capabilities of the Space Shuttle Orbiter beyond its current 7-10 day limit on mission duration, as warranted by deepening understanding of the long-term physiological effects of weightlessness. Attention is being given to the cardiovascular problem of orthostatic tolerance loss due to its adverse effects on crew performance and health during reentry and initial readaptation to earth gravity. An account is given of the results of the application of proven mathematical models of circulatory and cardiovascular systems under microgravity conditions.
Extended Parker-Sochacki method for Michaelis-Menten enzymatic reaction model.
Abdelrazik, Ismail M; Elkaranshawy, Hesham A
2016-03-01
In this article, a new approach--namely, the extended Parker-Sochacki method (EPSM)--is presented for solving the Michaelis-Menten nonlinear enzymatic reaction model. The Parker-Sochacki method (PSM) is combined with a new resummation method called the Sumudu-Padé resummation method to obtain approximate analytical solutions for the model. The obtained solutions by the proposed approach are compared with the solutions of PSM and the Runge-Kutta numerical method (RKM). The comparison proves the practicality, efficiency, and correctness of the presented approach. It serves as a basis for solving other nonlinear biochemical reaction models in the future. Copyright © 2015 Elsevier Inc. All rights reserved.
Extended kinetic model of real-time polymerase chain reaction process
Fedorov, A. A.; Sochivko, D. G.; Varlamov, D. A.; Kurochkin, V. E.
2016-11-01
Real-time polymerase chain reaction (real-time PCR) is the main molecular genetic method used for qualitative and quantitative analysis of specific nucleic acid sequences in many areas of biomedical research. Theoretical study of pCr models allows to estimate the influence of various reaction components and parameters, and to determine the unknown parameter values by approximating the experimental real-time PCR curves. An extended kinetic model of real-time PCR is presented. The model takes into account the enzyme activity based on Michaelis-Menten kinetics, the hybridization of complementary DNA fragments, the presence of a fluorescent probe used for detection of the reaction products, and the temperature dependence of primers and probe hybridization.
Existence of the critical endpoint in the vector meson extended linear sigma model
Kovács, Peter; Wolf, György
2016-01-01
The chiral phase transition of the strongly interacting matter is investigated at nonzero temperature and baryon chemical potential mu_B within an extended (2+1) flavor Polyakov constituent quark-meson model which incorporates the effect of the vector and axial vector mesons. The effect of the fermionic vacuum and thermal fluctuations computed from the grand potential of the model is taken into account in the curvature masses of the scalar and pseudoscalar mesons. The parameters of the model are determined by comparing masses and tree-level decay widths with experimental values in a chi^2-minimization procedure which selects between various possible assignments of scalar nonet states to physical particles. We examine the restoration of the chiral symmetry by monitoring the temperature evolution of condensates and the chiral partners' masses and of the mixing angles for the pseudoscalar eta-eta' and the corresponding scalar complex. We calculate the pressure and various thermodynamical observables derived from...
Relativistic modeling capabilities in PERSEUS extended MHD simulation code for HED plasmas
Energy Technology Data Exchange (ETDEWEB)
Hamlin, Nathaniel D., E-mail: nh322@cornell.edu [438 Rhodes Hall, Cornell University, Ithaca, NY, 14853 (United States); Seyler, Charles E., E-mail: ces7@cornell.edu [Cornell University, Ithaca, NY, 14853 (United States)
2014-12-15
We discuss the incorporation of relativistic modeling capabilities into the PERSEUS extended MHD simulation code for high-energy-density (HED) plasmas, and present the latest hybrid X-pinch simulation results. The use of fully relativistic equations enables the model to remain self-consistent in simulations of such relativistic phenomena as X-pinches and laser-plasma interactions. By suitable formulation of the relativistic generalized Ohm’s law as an evolution equation, we have reduced the recovery of primitive variables, a major technical challenge in relativistic codes, to a straightforward algebraic computation. Our code recovers expected results in the non-relativistic limit, and reveals new physics in the modeling of electron beam acceleration following an X-pinch. Through the use of a relaxation scheme, relativistic PERSEUS is able to handle nine orders of magnitude in density variation, making it the first fluid code, to our knowledge, that can simulate relativistic HED plasmas.
An extended two-dimensional mathematical model of vertical ring furnaces
Peter, S.; Charette, A.; Bui, R. T.; Tomsett, A.; Potocnik, V.
1996-04-01
An extended two-dimensional (2-D+) mathematical model of vertical anode baking furnaces has been developed. The work was motivated by the fact that a previous 2-D model was unable to predict the nonuniform baking in the transverse direction, i.e., perpendicular to the longitudinal axis of the furnace. The modeling strategy based on dividing each section in four zones (underlid, pit, underpit, head wall and fire shaft zones) and introducing two symmetry planes in the exterior pits is explained. The basic heat-transfer relations used are also detailed. Selected results shown include draught and oxygen concentration profiles in the flue, gas and anode temperature distributions and fuel consumption in the back fire ramp. Simulation and experimental results are compared.
Noguera, C; Goniakowski, J
2013-08-28
Relying on Frenkel Kontorova (FK) models of diatomic chains of increasing levels of complexity, this study presents an overall view of the diversity of structural effects that a compound (oxide) chain supported on a metal may display and helps assigning them to precise microscopic mechanisms. At each stage, the models are solved numerically, in order to provide phase diagrams as a function of chain-substrate interaction and misfit. Analytic derivations of transition lines are also provided within the continuum approximation. Their predictions are shown to quantitatively account for the numerical results, thus showing the validity of the continuum approximation in the misfit range under consideration. The present study thus extends our knowledge of the FK model by specifically focusing on diatomic chains and brings new information on a potentially interesting system which experimentalists just start being able to synthesize--oxide chains on metal substrates.
EXTENDING THE DEEP PACKET INSPECTION MODEL TO THE GCC/MENA REGION
Directory of Open Access Journals (Sweden)
Alfred H. Miller
2013-12-01
Full Text Available This study seeks to explore extending the technology acceptance model (DPAM from a 2011 quantitative study—Modeling Intention to Use Deep Packet Inspection Technology in the United Arab Emirates, to the cyber security practitioner community of the Gulf Cooperation Council (GCC and greater Middle East North Africa (MENA Region. Analysis of regression between independent variable model factors of computer self efficacy, attitude toward ICT, perceived usefulness of ecommerce, intention to use ecommerce, societal trust and Internet filtration toward the dependent variable intention to use deep packet inspection, to determine parsimony, using confirmatory factor analysis (CFA, multinomial regression to assess correlation of independent and dependent variables, and assessment of the cross-suitability of DPAM across the MENA/GCC states through a MANOVA assessment. A qualitative component of the instrument enables collection of data about specific hardware and software deployed for deep packet inspection and cyber security systems.
MILES extended: Stellar population synthesis models from the optical to the infrared
Röck, B; Ricciardelli, E; Peletier, R F; Knapen, J H; Falcon-Barroso, J
2016-01-01
We present the first single-burst stellar population models which covers the optical and the infrared wavelength range between 3500 and 50000 Angstrom and which are exclusively based on empirical stellar spectra. To obtain these joint models, we combined the extended MILES models in the optical with our new infrared models that are based on the IRTF (Infrared Telescope Facility) library. The latter are available only for a limited range in terms of both age and metallicity. Our combined single-burst stellar population models were calculated for ages larger than 1 Gyr, for metallicities between [Fe/H] = -0.40 and 0.26, for initial mass functions of various types and slopes, and on the basis of two different sets of isochrones. They are available to the scientific community on the MILES web page. We checked the internal consistency of our models and compared their colour predictions to those of other models that are available in the literature. Optical and near infrared colours that are measured from our models...
The effect of Jupiter oscillations on Juno gravity measurements
Durante, D; Iess, L
2016-01-01
Seismology represents a unique method to probe the interiors of giant planets. Recently, Saturn's f-modes have been indirectly observed in its rings, and there is strong evidence for the detection of Jupiter global modes by means of ground-based, spatially-resolved, velocimetry measurements. We propose to exploit Juno's extremely accurate radio science data by looking at the gravity perturbations that Jupiter's acoustic modes would produce. We evaluate the perturbation to Jupiter's gravitational field using the oscillation spectrum of a polytrope with index 1 and the corresponding radial eigenfunctions. We show that Juno will be most sensitive to the fundamental mode ($n=0$), unless its amplitude is smaller than 0.5 cm/s, i.e. 100 times weaker than the $n \\sim\\ 4 - 11$ modes detected by spatially-resolved velocimetry. The oscillations yield contributions to Juno's measured gravitational coefficients similar to or larger than those expected from shallow zonal winds (extending to depths less than 300 km). In th...
In vitro 3-D model based on extending time of culture for studying chronological epidermis aging.
Dos Santos, Morgan; Metral, Elodie; Boher, Aurélie; Rousselle, Patricia; Thepot, Amélie; Damour, Odile
2015-09-01
Skin aging is a complex phenomenon in which several mechanisms operate simultaneously. Among them, intrinsic aging is a time-dependent process, which leads to gradual skin changes affecting its structure and function such as thinning down of both epidermal and dermal compartments and a flattening and fragility of the dermo-epidermal junction. Today, several approaches have been proposed for the generation of aged skin in vitro, including skin explants from aged donors and three-dimensional skin equivalent treated by aging-inducing chemical compounds or engineered with human cells isolated from aged donors. The aim of this study was to develop and validate a new in vitro model of aging based on skin equivalent demonstrating the same phenotypic changes that were observed in chronological aging. By using prolonged culture as a proxy for cellular aging, we extended to 120 days the culture time of a skin equivalent model based on collagen-glycosaminoglycan-chitosan porous polymer and engineered with human skin cells from photo-protected sites of young donors. Morphological, immunohistological and ultrastructural analysis at different time points of the culture allowed characterizing the phenotypic changes observed in our model in comparison to samples of non photo-exposed normal human skin from different ages. We firstly confirmed that long-term cultured skin equivalents are still morphologically consistent and functionally active even after 120 days of culture. However, similar to in vivo chronological skin aging a significant decrease of the epidermis thickness as well as the number of keratinocyte expressing proliferation marker Ki67 are observed in extended culture time skin equivalent. Epidermal differentiation markers loricrin, filaggrin, involucrin and transglutaminase, also strongly decreased. Ultrastructural analysis of basement membrane showed typical features of aged skin such as duplication of lamina densa and alterations of hemidesmosomes. Moreover, the
An Extended Non-Lane-Based Optimal Velocity Model with Dynamic Collaboration
Directory of Open Access Journals (Sweden)
Zhipeng Li
2013-01-01
Full Text Available Incorporating the effects of the lane width in traffic, in this paper, we propose a dynamical model based on the strategy of three-vehicle cooperation driving. We obtain the smoother acceleration distribution in the new model through considering the dynamic collaboration with the nearest preceding vehicle and the nearest following vehicle. It is proved that the stability of the new model is greatly improved compared to the early non-lane-based car following model by using the linear stability theory. We find that when the parameter of lateral separation distance is identified, the amplitude of traffic congestion decreases with increasing the strength of dynamic collaboration in the simulation experiments. In addition, we apply the new extended model to simulate the motions of cars starting from a traffic signal and the dissipating of the traffic congestion; it is found that our new model can predict realistic delay time and kinematic wave speed and obtained a faster dissipation speed of traffic congestion than the traffic flow model without considering the dynamic collaboration.
Wan, Rui; Durlach, Nathaniel I; Colburn, H Steven
2010-12-01
An extended version of the equalization-cancellation (EC) model of binaural processing is described and applied to speech intelligibility tasks in the presence of multiple maskers. The model incorporates time-varying jitters, both in time and amplitude, and implements the equalization and cancellation operations in each frequency band independently. The model is consistent with the original EC model in predicting tone-detection performance for a large set of configurations. When the model is applied to speech, the speech intelligibility index is used to predict speech intelligibility performance in a variety of conditions. Specific conditions addressed include different types of maskers, different numbers of maskers, and different spatial locations of maskers. Model predictions are compared with empirical measurements reported by Hawley et al. [J. Acoust. Soc. Am. 115, 833-843 (2004)] and by Marrone et al. [J. Acoust. Soc. Am. 124, 1146-1158 (2008)]. The model succeeds in predicting speech intelligibility performance when maskers are speech-shaped noise or broadband-modulated speech-shaped noise but fails when the maskers are speech or reversed speech.
Pairwise Interaction Extended Point Particle (PIEP) Model for a Random Array of Spheres
Akiki, Georges; Jackson, Thomas; Balachandar, Sivaramakrishnan; CenterCompressible Multiphase Turbulence Team
2016-11-01
This study investigates a flow past random array of spherical particles. The understanding of the governing forces within these arrays is crucial for obtaining accurate models used in particle-laden simulations. These models have to faithfully reflect the sub-grid interactions between the particles and the continuous phase. The models being used today assumes an average force on all particles within the array based on the mean volume fraction and Reynolds number. Here, we develop a model which can compute the drag and lateral forces on each particle by accounting for the precise location of few surrounding neighbors. A pairwise interaction is assumed where the perturbation flow induced by each neighbor is considered separately, then the effect of all neighbors are linearly superposed to obtain the total perturbation. Faxén correction is used to quantify the force perturbation due to the presence of the neighbors. The single neighbor perturbations are mapped in the vicinity of a reference sphere and stored as libraries. We test the Pairwise Interaction Extended Point-Particle (PIEP) model for random arrays at two different volume fractions of ϕ = 0 . 1 and 0.21 and Reynolds number in the range 16 DNS performed using immersed boundary method. We observe the PIEP model prediction to correlate much better with the DNS results than the classical mean drag model prediction.
Longitudinal Variations in Jupiter's Winds
Simon-Miller, Amy A.; Gierasch, P. J.; Tierney, G.
2010-01-01
Long-term studies of Jupiter's zonal wind field revealed temporal variations on the order of 20 to 40 m/s at many latitudes, greater than the typical data uncertainties of 1 to 10 m/s. No definitive periodicities were evident, however, though some latitudinally-confined signals did appear at periods relevant to the Quasi- Quadrennial Oscillation (Simon-Miller & Gierasch, Icarus, in press). As the QQO appears, from vertical temperature profiles, to propagate downward, it is unclear why a signal is not more obvious, unless other processes dominate over possibly weaker forcing from the QQO. An additional complication is that zonal wind profiles represent an average over some particular set of longitudes for an image pair and most data sets do not offer global wind coverage. Lien avoiding known features, such as the large anticyclonic vortices especially prevalent in the south, there can be distinct variations in longitude. We present results on the full wind field from Voyager and Cassini data, showing apparent longitudinal variations of up to 60 m/s or more. These are particularly obvious near disruptions such as the South Equatorial Disturbance, even when the feature itself is not clearly visible. These two dates represent very different states of the planet for comparison: Voyagers 1 & 2 flew by Jupiter shortly after a global upheaval, while many regions were in a disturbed state, while the Cassini view is typical of a more quiescent period present during much of the 1990s and early 2000s.
The New Horizons Mission to Pluto and Flyby of Jupiter
Stern, Alan; Weaver, Hal; Young, Leslie; Bagenal, Fran; Binzel, Richard; Buratti, Bonnie; Cheng, andy; Cruikshank, Dale; Gladstone, Randy; Grundy, Will; Hinson, David; Horanyi, Mihaly; Jennings, Don; Linscott, Ivan; McComas, Dave; McKinnon, William; McNutt, Ralph; Moore, Jeffrey; Murchie, Scott; Olkin, Cathy; Porco, Carolyn; Reitsema, Harold; Reuter, Dennis; Slater, Dave; Spencer, John
2008-01-01
New Horizons (NH) is NASA's mission to provide the first in situ reconnaissance of Pluto and its moons Charon, Nix, and Hydra. The NH spacecraft will reach Pluto in July 2015 and will then, if approved for an extended mission phase, continue on to a flyby encounter with one or more Kuiper belt objects (KBOs). NH was launched on 19 January 2006 and received a gravity assist during a flyby encounter with Jupiter (with closest approach at -32 RJ on 28 February 2007) that reduced its flight time to Pluto by 3 years. During the Jupiter flyby, NH collected a trove of multi-wavelength imaging and fields-and-particles measurements. Among the many science results at Jupiter were a detection of planet-wide mesoscale waves, eruptions of atmospheric ammonia clouds, unprecedented views of Io's volcanic plumes and Jupiter's tenuous ring system, a first close-up of the Little Red Spot (LRS), first sightings of polar lightning, and a trip down the tail of the magnetosphere. In 2015, NH will conduct a seven-month investigation of the Pluto system culminating in a closest approach some 12,500 km from Pluto's surface. Planning is presently underway for the Pluto encounter with special emphasis on longidentified science goals of studying the terrain, geology, and composition of the surfaces of Pluto and Charon, examining the composition and structure of Pluto's atmosphere, searching for an atmosphere on Charon, and characterizing Pluto's ionosphere and solar wind interaction. Detailed inspections will also be performed of the newly discovered satellites Nix and Hydra. Additionally, NH will characterize energetic particles in Pluto's environment, refine the bulk properties of Pluto and Charon, and search for additional satellites and rings.
Engineering a Solution to Jupiter Exploration
Clark, Karla; Magner, Thomas; Lisano, Michael; Pappalardo, Robert
2010-01-01
The Europa Jupiter System Mission (EJSM) would be an international mission with the overall theme of investigating the emergence of habitable worlds around gas giants. Its goals are to (1) explore Europa to investigate its habitability, (2) characterize Ganymede as a planetary object including its potential habitability and (3) explore the Jupiter system as an archetype for gas giants. NASA and ESA have concluded a detailed joint study of a mission to Europa, Ganymede, and the Jupiter system with conceptual orbiters developed by NASA and ESA. The baseline EJSM architecture consists of two primary elements operating simultaneously in the Jovian system: the NASA-led Jupiter Europa Orbiter (JEO), and the ESA-led Jupiter Ganymede Orbiter (JGO). JEO and JGO would execute an intricately choreographed exploration of the Jupiter System before settling into orbit around Europa and Ganymede, respectively. EJSM would directly address themes concerning the origin and evolution of satellite systems and water-rich environments in icy satellites. The potential habitability of the ocean-bearing moons Europa and Ganymede would be investigated, by characterizing the geophysical, compositional, geological, and external processes that affect these icy worlds. EJSM would also investigate Io and Callisto, Jupiter's atmosphere, and the Jovian magnetosphere. By understanding the Jupiter system and unraveling its history, the formation and evolution of gas giant planets and their satellites would be better known. Most importantly, EJSM would shed new light on the potential for the emergence of life in the celestial neighborhood and beyond. The EJSM baseline architecture would provide opportunities for coordinated synergistic observations by JEO and JGO of the Jupiter and Ganymede magnetospheres, the volcanoes and torus of Io, the atmosphere of Jupiter, and comparative planetology of icy satellites. Each spacecraft would conduct both synergistic dual-spacecraft investigations and stand
Re-inflated Warm Jupiters Around Red Giants
Lopez, Eric D
2015-01-01
Since the discovery of the first transiting hot Jupiters, models have sought to explain the anomalously large radii of highly irradiated gas giants. We now know that the size of hot Jupiter radius anomalies scales strongly with a planet's level of irradiation and numerous models like tidal heating, ohmic dissipation, and thermal tides have since been developed to help explain these inflated radii. In general however, these models can be grouped into two broad categories: 1) models that directly inflate planetary radii by depositing a fraction of the incident irradiation into the interior and 2) models that simply slow a planet's radiative cooling allowing it to retain more heat from formation and thereby delay contraction. Here we present a new test to distinguish between these two classes of models. Gas giants orbiting at moderate orbital periods around post main sequence stars will experience enormous increases their irradiation as their host stars move up the sub-giant and red-giant branches. If hot Jupite...
The Composition of Dust in Jupiter-Family Comets as Inferred from Infrared Spectroscopy
Kelley, Michael S
2008-01-01
We review the composition of Jupiter-family comet dust as inferred from infrared spectroscopy. We find that Jupiter-family comets have 10 micron silicate emission features with fluxes roughly 20-25% over the dust continuum (emission strength 1.20-1.25), similar to the weakest silicate features in Oort Cloud comets. We discuss the grain properties that change the silicate emission feature strength (composition, size, and structure/shape), and emphasize that thermal emission from the comet nucleus can have significant influence on the derived silicate emission strength. Recent evidence suggests that porosity is the dominant parameter, although more observations and models of silicates in Jupiter-family comets are needed to determine if a consistent set of grain parameters can explain their weak silicate emission features. Models of 8 m telescope and Spitzer Space Telescope observations have shown that Jupiter-family comets have crystalline silicates with abundances similar to or less than those found in Oort Cl...
Extended Cann Model for Behavioral Modeling of Envelope Tracking Power Amplifiers
DEFF Research Database (Denmark)
Tafuri, Felice Francesco; Larsen, Torben
2013-01-01
This paper deals with behavioral modeling of power amplifiers (PAs) for envelope tracking (ET) applications. In such a scenario, the power supply modulation brings in several additional challenges for the system design and, similarly, it becomes more difficult to obtain an accurate and general PA...... by the ET operation. The model performance is tested modeling data-sets acquired from an ET test bench including a commercial RFMD PA and an envelope modulator designed using a commercial IC from TI....