Planetesimal Formation by the Streaming Instability in a Photoevaporating Disk

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Carrera, Daniel; Johansen, Anders; Davies, Melvyn B. [Lund Observatory, Dept. of Astronomy and Theoretical Physics, Lund University, Box 43, SE-221 00 Lund (Sweden); Gorti, Uma [NASA Ames Research Center, Moffett Field, CA (United States)

2017-04-10

Recent years have seen growing interest in the streaming instability as a candidate mechanism to produce planetesimals. However, these investigations have been limited to small-scale simulations. We now present the results of a global protoplanetary disk evolution model that incorporates planetesimal formation by the streaming instability, along with viscous accretion, photoevaporation by EUV, FUV, and X-ray photons, dust evolution, the water ice line, and stratified turbulence. Our simulations produce massive (60–130 M {sub ⊕}) planetesimal belts beyond 100 au and up to ∼20 M {sub ⊕} of planetesimals in the middle regions (3–100 au). Our most comprehensive model forms 8 M {sub ⊕} of planetesimals inside 3 au, where they can give rise to terrestrial planets. The planetesimal mass formed in the inner disk depends critically on the timing of the formation of an inner cavity in the disk by high-energy photons. Our results show that the combination of photoevaporation and the streaming instability are efficient at converting the solid component of protoplanetary disks into planetesimals. Our model, however, does not form enough early planetesimals in the inner and middle regions of the disk to give rise to giant planets and super-Earths with gaseous envelopes. Additional processes such as particle pileups and mass loss driven by MHD winds may be needed to drive the formation of early planetesimal generations in the planet-forming regions of protoplanetary disks.

GLOBAL HIGH-RESOLUTION N-BODY SIMULATION OF PLANET FORMATION. I. PLANETESIMAL-DRIVEN MIGRATION

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Kominami, J. D. [Earth-Life Science Institute, Tokyo Institute of Technology, Meguro-Ku, Tokyo (Japan); Daisaka, H. [Hitotsubashi University, Kunitachi-shi, Tokyo (Japan); Makino, J. [RIKEN Advanced Institute for Computational Science, Chuo-ku, Kobe, Hyogo (Japan); Fujimoto, M., E-mail: kominami@mail.jmlab.jp, E-mail: daisaka@phys.science.hit-u.ac.jp, E-mail: makino@mail.jmlab.jp, E-mail: fujimoto.masaki@jaxa.jp [Japan Aerospace Exploration Agency, Sagamihara-shi, Kanagawa (Japan)

2016-03-01

We investigated whether outward planetesimal-driven migration (PDM) takes place or not in simulations when the self-gravity of planetesimals is included. We performed N-body simulations of planetesimal disks with a large width (0.7–4 au) that ranges over the ice line. The simulations consisted of two stages. The first-stage simulations were carried out to see the runaway growth phase using the planetesimals of initially the same mass. The runaway growth took place both at the inner edge of the disk and at the region just outside the ice line. This result was utilized for the initial setup of the second-stage simulations, in which the runaway bodies just outside the ice line were replaced by the protoplanets with about the isolation mass. In the second-stage simulations, the outward migration of the protoplanet was followed by the stopping of the migration due to the increase of the random velocity of the planetesimals. Owing to this increase of random velocities, one of the PDM criteria derived in Minton and Levison was broken. In the current simulations, the effect of the gas disk is not considered. It is likely that the gas disk plays an important role in PDM, and we plan to study its effect in future papers.

PLANET-PLANET SCATTERING IN PLANETESIMAL DISKS

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Raymond, Sean N.; Armitage, Philip J.; Gorelick, Noel

2009-01-01

We study the final architecture of planetary systems that evolve under the combined effects of planet-planet and planetesimal scattering. Using N-body simulations we investigate the dynamics of marginally unstable systems of gas and ice giants both in isolation and when the planets form interior to a planetesimal belt. The unstable isolated systems evolve under planet-planet scattering to yield an eccentricity distribution that matches that observed for extrasolar planets. When planetesimals are included the outcome depends upon the total mass of the planets. For M tot ∼> 1 M J the final eccentricity distribution remains broad, whereas for M tot ∼ J a combination of divergent orbital evolution and recircularization of scattered planets results in a preponderance of nearly circular final orbits. We also study the fate of marginally stable multiple planet systems in the presence of planetesimal disks, and find that for high planet masses the majority of such systems evolve into resonance. A significant fraction leads to resonant chains that are planetary analogs of Jupiter's Galilean satellites. We predict that a transition from eccentric to near-circular orbits will be observed once extrasolar planet surveys detect sub-Jovian mass planets at orbital radii of a ≅ 5-10 AU.

Dispersion of the Himalia family of jovian irregular satellites by planetesimal encounters

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Li, Daohai; Christou, Apostolos

2017-06-01

removed, further modifying the group.We propose that, if the formation of the Himalia group occurred before the end of the migration phase, planetesimal-induced dispersion must have contributed significantly to the orbital distribution of the observed group.

Xenon fractionation in porous planetesimals

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Zahnle, Kevin; Pollack, James B.; Kasting, James F.

1990-01-01

The distinctively fractionated Xe on Mars and earth may have its root in a common source from which both planets accreted. Beginning with Ozima and Nakazawa's (1980) hypothesis that terrestrial Xe fractionation was caused by gravitational separation of adsorbed solar nebular gases inside large porous planetesimals, it is pointed out that Xe would have been trapped as the planetesimal grew and pores were squeezed shut by lithostatic pressure. It is shown that enough fractionated Xe to supply the earth could have been trapped this way. The degree of fractionation is controlled by the lithostatic pressure at the pore-closing front and so would have been roughly the same for all large planetesimals. The predicted degree of fractionation agrees well with that preserved in terrestrial and Martian Xe. Relative to Xe, this source is strongly depleted in other noble gases. In contrast to the original Ozima and Nakazawa hypothesis, the present hypothesis predicts the observed fractionation, and it allows planetary accretion to occur after the dissipation of the solar nebula.

Implications of the interstellar object 1I/'Oumuamua for planetary dynamics and planetesimal formation

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Raymond, Sean N.; Armitage, Philip J.; Veras, Dimitri; Quintana, Elisa V.; Barclay, Thomas

2018-05-01

'Oumuamua, the first bona fide interstellar planetesimal, was discovered passing through our Solar system on a hyperbolic orbit. This object was likely dynamically ejected from an extrasolar planetary system after a series of close encounters with gas giant planets. To account for 'Oumuamua's detection, simple arguments suggest that ˜1 M⊕ of planetesimals are ejected per solar mass of Galactic stars. However, that value assumes mono-sized planetesimals. If the planetesimal mass distribution is instead top-heavy, the inferred mass in interstellar planetesimals increases to an implausibly high value. The tension between theoretical expectations for the planetesimal mass function and the observation of 'Oumuamua can be relieved if a small fraction ({˜ } 0.1-1 {per cent}) of planetesimals are tidally disrupted on the pathway to ejection into 'Oumuamua-sized fragments. Using a large suite of simulations of giant planet dynamics including planetesimals, we confirm that 0.1-1 per cent of planetesimals pass within the tidal disruption radius of a gas giant on their pathway to ejection. 'Oumuamua may thus represent a surviving fragment of a disrupted planetesimal. Finally, we argue that an asteroidal composition is dynamically disfavoured for 'Oumuamua, as asteroidal planetesimals are both less abundant and ejected at a lower efficiency than cometary planetesimals.

PLANET FORMATION IN STELLAR BINARIES. I. PLANETESIMAL DYNAMICS IN MASSIVE PROTOPLANETARY DISKS

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Rafikov, Roman R.; Silsbee, Kedron

2015-01-01

About 20% of exoplanets discovered by radial velocity surveys reside in stellar binaries. To clarify their origin one has to understand the dynamics of planetesimals in protoplanetary disks within binaries. The standard description, accounting for only gas drag and gravity of the companion star, has been challenged recently, as the gravity of the protoplanetary disk was shown to play a crucial role in planetesimal dynamics. An added complication is the tendency of protoplanetary disks in binaries to become eccentric, giving rise to additional excitation of planetesimal eccentricity. Here, for the first time, we analytically explore the secular dynamics of planetesimals in binaries such as α Cen and γ Cep under the combined action of (1) gravity of the eccentric protoplanetary disk, (2) perturbations due to the (coplanar) eccentric companion, and (3) gas drag. We derive explicit solutions for the behavior of planetesimal eccentricity e p in non-precessing disks (and in precessing disks in certain limits). We obtain the analytical form of the distribution of the relative velocities of planetesimals, which is a key input for understanding their collisional evolution. Disk gravity strongly influences relative velocities and tends to push the sizes of planetesimals colliding with comparable objects at the highest speed to small values, ∼1 km. We also find that planetesimals in eccentric protoplanetary disks apsidally aligned with the binary orbit collide at lower relative velocities than in misaligned disks. Our results highlight the decisive role that disk gravity plays in planetesimal dynamics in binaries

ROCKY PLANETESIMAL FORMATION VIA FLUFFY AGGREGATES OF NANOGRAINS

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Arakawa, Sota; Nakamoto, Taishi, E-mail: arakawa.s.ac@m.titech.ac.jp [Department of Earth and Planetary Sciences, Tokyo Institute of Technology, Meguro, Tokyo 152-8551 (Japan)

2016-12-01

Several pieces of evidence suggest that silicate grains in primitive meteorites are not interstellar grains but condensates formed in the early solar system. Moreover, the size distribution of matrix grains in chondrites implies that these condensates might be formed as nanometer-sized grains. Therefore, we propose a novel scenario for rocky planetesimal formation in which nanometer-sized silicate grains are produced by evaporation and recondensation events in early solar nebula, and rocky planetesimals are formed via aggregation of these nanograins. We reveal that silicate nanograins can grow into rocky planetesimals via direct aggregation without catastrophic fragmentation and serious radial drift, and our results provide a suitable condition for protoplanet formation in our solar system.

Planetesimals Born Big by Clustering Instability?

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Cuzzi, Jeffrey N.; Hartlep, Thomas; Simon, Justin I.; Estrada, Paul R.

2017-01-01

Roughly 100km diameter primitive bodies (today's asteroids and TNOs; [1]) are thought to be the end product of so-called "primary accretion". They dominated the initial mass function of planetesimals, and precipitated the onset of a subsequent stage, characterized by runaway gravitational effects, which proceeded onwards to planetary mass objects, some of which accreted massive gas envelopes. Asteroids are the parents of primitive meteorites; meteorite data suggest that asteroids initially formed directly from freelyfloating nebula particles in the mm-size range. Unfortunately, the process by which these primary 100km diameter planetesimals formed remains problematic. We review the most diagnostic primitive parent body observations, highlight critical aspects of the nebula context, and describe the issues facing various primary accretion models. We suggest a path forward that combines current scenarios of "turbulent concentration" (TC) and "streaming instabilities" (SI) into a triggered formation process we call clustering instability (CI). Under expected conditions of nebula turbulence, the success of these processes at forming terrestrial region (mostly silicate) planetesimals requires growth by sticking into aggregates in the several cm size range, at least, which is orders of magnitude more massive than allowed by current growth-by-sticking models using current experimental sticking parameters [2-4]. The situation is not as dire in the ice-rich outer solar system; however, growth outside of the snowline has important effects on growth inside of it [4] and at least one aspect of outer solar system planetesimals (high binary fraction) supports some kind of clustering instability

Accretion of Planetesimals and the Formation of Rocky Planets

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Chambers, John E.; O'Brien, David P.; Davis, Andrew M.

2010-02-01

Here we describe the formation of rocky planets and asteroids in the context of the planetesimal hypothesis. Small dust grains in protoplanetary disks readily stick together forming mm-to-cm-sized aggregates, many of which experience brief heating episodes causing melting. Growth to km-sized planetesimals might proceed via continued pairwise sticking, turbulent concentration, or gravitational instability of a thin particle layer. Gravitational interactions between planetesimals lead to rapid runaway and oligarchic growth forming lunar-to-Mars-sized protoplanets in 10^5 to 10^6 years. Giant impacts between protoplanets form Earth-mass planets in 10^7 to 10^8 years, and occasionally lead to the formation of large satellites. Protoplanets may migrate far from their formation locations due to tidal interactions with the surrounding disk. Radioactive decay and impact heating cause melting and differentiation of planetesimals and protoplanets, forming iron-rich cores and silicate mantles, and leading to some loss of volatiles. Dynamical perturbations from giant planets eject most planetesimals and protoplanets from regions near orbital resonances, leading to asteroid-belt formation. Some of this scattered material will collide with growing terrestrial planets, altering their composition as a result. Numerical simulations and radioisotope dating indicate that the terrestrial planets of the Solar System were essentially fully formed in 100-200 million years.

Simulations of small solid accretion on to planetesimals in the presence of gas

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Hughes, A. G.; Boley, A. C.

2017-12-01

The growth and migration of planetesimals in a young protoplanetary disc are fundamental to planet formation. In all models of early growth, there are several processes that can inhibit grains from reaching larger sizes. Nevertheless, observations suggest that growth of planetesimals must be rapid. If a small number of 100 km sized planetesimals do manage to form in the disc, then gas drag effects could enable them to efficiently accrete small solids from beyond their gravitationally focused cross-section. This gas-drag-enhanced accretion can allow planetesimals to grow at rapid rates, in principle. We present self-consistent hydrodynamics simulations with direct particle integration and gas-drag coupling to estimate the rate of planetesimal growth due to pebble accretion. Wind tunnel simulations are used to explore a range of particle sizes and disc conditions. We also explore analytic estimates of planetesimal growth and numerically integrate planetesimal drift due to the accretion of small solids. Our results show that, for almost every case that we consider, there is a clearly preferred particle size for accretion that depends on the properties of the accreting planetesimal and the local disc conditions. For solids much smaller than the preferred particle size, accretion rates are significantly reduced as the particles are entrained in the gas and flow around the planetesimal. Solids much larger than the preferred size accrete at rates consistent with gravitational focusing. Our analytic estimates for pebble accretion highlight the time-scales that are needed for the growth of large objects under different disc conditions and initial planetesimal sizes.

Elemental compositions of two extrasolar rocky planetesimals

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Xu, S.; Jura, M.; Klein, B.; Zuckerman, B. [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095-1562 (United States); Koester, D., E-mail: sxu@astro.ucla.edu, E-mail: jura@astro.ucla.edu, E-mail: kleinb@astro.ucla.edu, E-mail: ben@astro.ucla.edu, E-mail: koester@astrophysik.uni-kiel.de [Institut fur Theoretische Physik und Astrophysik, University of Kiel, D-24098 Kiel (Germany)

2014-03-10

We report Keck/HIRES and Hubble Space Telescope/COS spectroscopic studies of extrasolar rocky planetesimals accreted onto two hydrogen atmosphere white dwarfs, G29-38 and GD 133. In G29-38, eight elements are detected, including C, O, Mg, Si, Ca, Ti, Cr, and Fe while in GD 133, O, Si, Ca, and marginally Mg are seen. These two extrasolar planetesimals show a pattern of refractory enhancement and volatile depletion. For G29-38, the observed composition can be best interpreted as a blend of a chondritic object with some refractory-rich material, a result from post-nebular processing. Water is very depleted in the parent body accreted onto G29-38, based on the derived oxygen abundance. The inferred total mass accretion rate in GD 133 is the lowest of all known dusty white dwarfs, possibly due to non-steady state accretion. We continue to find that a variety of extrasolar planetesimals all resemble to zeroth order the elemental composition of bulk Earth.

PLANETESIMAL ACCRETION IN BINARY SYSTEMS: ROLE OF THE COMPANION'S ORBITAL INCLINATION

International Nuclear Information System (INIS)

Xie Jiwei; Zhou Jilin

2009-01-01

Recent observations show that planets can reside in close binary systems with stellar separation of only ∼20 AU. However, planet formation in such close binary systems is a challenge to current theory. One of the major theoretical problems occurs in the intermediate stage-planetesimals accretion into planetary embryos-during which the companion's perturbations can stir up the relative velocities (utriV) of planetesimals and thus slow down or even cease their growth. Recent studies have shown that conditions could be even worse for accretion if the gas-disk evolution was included. However, all previous studies assumed a two-dimensional disk and a coplanar binary orbit. Extending previous studies by including a three-dimensional gas disk and an inclined binary orbit with small relative inclination of i B = 0. 0 1-5 0 , we numerically investigate the conditions for planetesimal accretion at 1-2 AU, an extension of the habitable zone (∼1-1.3 AU), around α Centauri A in this paper. Inclusion of the binary inclination leads to the following: (1) differential orbital phasing is realized in the three-dimensional space, and thus different-sized bodies are separated from each other, (2) total impact rate is lower, and impacts mainly occur between similar-sized bodies, (3) accretion is more favored, but the balance between accretion and erosion remains uncertain, and the 'possible accretion region' extends up to 2 AU when assuming an optimistic Q* (critical specific energy that leads to catastrophic fragmentation), and (4) impact velocities (utriV) are significantly reduced but still much larger than their escape velocities, which infers that planetesimals grow by means of type II runaway mode. As a conclusion, the inclusion of a small binary inclination is a promising mechanism that favors accretion, opening a possibility that planet formation in close binary systems can go through the difficult stage of planetesimals accretion into planetary embryos.

From Dust Grains to Planetesimals: The Importance of the Streaming Instability in Protoplanetary Disks

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Simon, Jacob B.; Armitage, Philip J.; Youdin, Andrew N.; Li, Rixin

2016-01-01

Planetesimals are the precursors to planets, and understanding their formation is an essential step towards developing a complete theory of planet formation. For small solid particles (e.g., dust grains) to coagulate into planetesimals, however, requires that these particles grow beyond centimeter sizes; with traditional coagulation physics, this is very difficult. The streaming instability, which is a clumping process akin to the pile-up of cars in a traffic jam, generates sufficiently high solid densities that the mutual gravity between the clumped particles eventually causes their collapse towards planetesimal mass and size scales. Exploring this transition from dust grains to planetesimals is still in its infancy but is extremely important if we want to understand the basics of planet formation. Here, I present a series of high resolution, first principles numerical simulations of protoplanetary disk gas and dust to study the clumping of particles via the streaming instability and the subsequent collapse towards planetesimals. These simulations have been employed to characterize the planetesimal population as a function of radius in protoplanetary disks. The results of these simulations will be crucial for planet formation models to correctly explain the formation and configuration of solar systems.

WILL THE LARGE SYNOPTIC SURVEY TELESCOPE DETECT EXTRA-SOLAR PLANETESIMALS ENTERING THE SOLAR SYSTEM?

International Nuclear Information System (INIS)

Moro-Martin, Amaya; Turner, Edwin L.; Loeb, Abraham

2009-01-01

Planetesimal formation is a common by-product of the star formation process. Taking the dynamical history of the solar system as a guideline-in which the planetesimal belts were heavily depleted due to gravitational perturbation with the giant planets-and assuming similar processes have taken place in other planetary systems, one would expect the interstellar space to be filled with extra-solar planetesimals. However, not a single one of these objects has been detected so far entering the solar system, even though it would clearly be distinguishable from a solar system comet due to its highly hyperbolic orbit. The Large Synoptic Survey Telescope (LSST) will provide wide coverage maps of the sky to a very high sensitivity, ideal to detect moving objects like comets, both active and inactive. In anticipation of these observations, we estimate how many inactive 'interstellar comets' might be detected during the duration of the survey. The calculation takes into account estimates (from observations and models) of the number density of stars, the amount of solids available to form planetesimals, the frequency of planet and planetesimal formation, the efficiency of planetesimal ejection, and the possible size distribution of these small bodies.

MIGRATION RATES OF PLANETS DUE TO SCATTERING OF PLANETESIMALS

International Nuclear Information System (INIS)

Ormel, C. W.; Ida, S.; Tanaka, H.

2012-01-01

Planets migrate due to the recoil they experience from scattering solid (planetesimal) bodies. To first order, the torques exerted by the interior and exterior disks will cancel, analogous to the cancellation of the torques from the gravitational interaction with the gas (Type-I migration). Assuming the dispersion-dominated regime and power laws characterized by indices α and β for the surface density and eccentricity profiles, we calculate the net torque on the planet. We consider both distant encounters and close (orbit-crossing) encounters. We find that the close and distant encounter torques have opposite signs with respect to α and β; and that the torque is especially sensitive to the eccentricity gradient β. Compared to Type-I migration due to excitation of density waves, the planetesimal-driven migration rate is generally lower due to the lower surface density of solids in gas-rich disk, although this may be partially or fully offset when their eccentricity and inclinaton are small. Allowing for the feedback of the planet on the planetesimal disk through viscous stirring, we find that under certain conditions a self-regulated migration scenario emerges, in which the planet migrates at a steady pace that approaches the rate corresponding to the one-sided torque. If the ratio of the local disk mass in planetesimals to planet mass is low, however, migration will stall. We quantify the boundaries separating the three accretion regimes.

Planetesimals around nearby millisecond pulsars

International Nuclear Information System (INIS)

Chakrabarti, S.K.

1992-05-01

We predict that it is possible to observe line emissions of OH, CN and C 2 from the planetesimals around some of the nearby millisecond pulsars, such as PSR1257+12. Observation of these lines will provide an independent test of either an existing planetary system or one which is in the process of formation. (author). 11 refs, 1 tab

Resolving the planetesimal belt of HR 8799 with ALMA

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Booth, Mark; Jordán, Andrés; Casassus, Simon; Hales, Antonio S.; Dent, William R. F.; Faramaz, Virginie; Matrà, Luca; Barkats, Denis; Brahm, Rafael; Cuadra, Jorge

2016-07-01

The star HR 8799 hosts one of the largest known debris discs and at least four giant planets. Previous observations have found evidence for a warm belt within the orbits of the planets, a cold planetesimal belt beyond their orbits and a halo of small grains. With the infrared data, it is hard to distinguish the planetesimal belt emission from that of the grains in the halo. With this in mind, the system has been observed with ALMA in band 6 (1.34 mm) using a compact array format. These observations allow the inner edge of the planetesimal belt to be resolved for the first time. A radial distribution of dust grains is fitted to the data using an MCMC method. The disc is best fitted by a broad ring between 145^{+12}_{-12} au and 429^{+37}_{-32} au at an inclination of 40^{+5}_{-6}° and a position angle of 51^{+8}_{-8}°. A disc edge at ˜145 au is too far out to be explained simply by interactions with planet b, requiring either a more complicated dynamical history or an extra planet beyond the orbit of planet b.

The effects of short-lived radionuclides and porosity on the early thermo-mechanical evolution of planetesimals

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Lichtenberg, Tim; Golabek, Gregor J.; Gerya, Taras V.; Meyer, Michael R.

2016-08-01

The thermal history and internal structure of chondritic planetesimals, assembled before the giant impact phase of chaotic growth, potentially yield important implications for the final composition and evolution of terrestrial planets. These parameters critically depend on the internal balance of heating versus cooling, which is mostly determined by the presence of short-lived radionuclides (SLRs), such as 26Al and 60Fe, as well as the heat conductivity of the material. The heating by SLRs depends on their initial abundances, the formation time of the planetesimal and its size. It has been argued that the cooling history is determined by the porosity of the granular material, which undergoes dramatic changes via compaction processes and tends to decrease with time. In this study we assess the influence of these parameters on the thermo-mechanical evolution of young planetesimals with both 2D and 3D simulations. Using the code family I2ELVIS/I3ELVIS we have run numerous 2D and 3D numerical finite-difference fluid dynamic models with varying planetesimal radius, formation time and initial porosity. Our results indicate that powdery materials lowered the threshold for melting and convection in planetesimals, depending on the amount of SLRs present. A subset of planetesimals retained a powdery surface layer which lowered the thermal conductivity and hindered cooling. The effect of initial porosity was small, however, compared to those of planetesimal size and formation time, which dominated the thermo-mechanical evolution and were the primary factors for the onset of melting and differentiation. We comment on the implications of this work concerning the structure and evolution of these planetesimals, as well as their behavior as possible building blocks of terrestrial planets.

INITIAL PLANETESIMAL SIZES AND THE SIZE DISTRIBUTION OF SMALL KUIPER BELT OBJECTS

International Nuclear Information System (INIS)

Schlichting, Hilke E.; Fuentes, Cesar I.; Trilling, David E.

2013-01-01

The Kuiper Belt is a remnant from the early solar system and its size distribution contains many important constraints that can be used to test models of planet formation and collisional evolution. We show, by comparing observations with theoretical models, that the observed Kuiper Belt size distribution is well matched by coagulation models, which start with an initial planetesimal population with radii of about 1 km, and subsequent collisional evolution. We find that the observed size distribution above R ∼ 30 km is primordial, i.e., it has not been modified by collisional evolution over the age of the solar system, and that the size distribution below R ∼ 30 km has been modified by collisions and that its slope is well matched by collisional evolution models that use published strength laws. We investigate in detail the resulting size distribution of bodies ranging from 0.01 km to 30 km and find that its slope changes several times as a function of radius before approaching the expected value for an equilibrium collisional cascade of material strength dominated bodies for R ∼< 0.1 km. Compared to a single power-law size distribution that would span the whole range from 0.01 km to 30 km, we find in general a strong deficit of bodies around R ∼ 10 km and a strong excess of bodies around 2 km in radius. This deficit and excess of bodies are caused by the planetesimal size distribution left over from the runaway growth phase, which left most of the initial mass in small planetesimals while only a small fraction of the total mass is converted into large protoplanets. This excess mass in small planetesimals leaves a permanent signature in the size distribution of small bodies that is not erased after 4.5 Gyr of collisional evolution. Observations of the small Kuiper Belt Object (KBO) size distribution can therefore test if large KBOs grew as a result of runaway growth and constrained the initial planetesimal sizes. We find that results from recent KBO

The origin of the planetesimal theory.

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Brush, S G

1977-04-01

T. C. Chamberlin suggested in 1897, on the basis of geological and climatological arguments, that the planets were formed by accretion of cold solid partices. With F. R. Moulton he developed convincing arguments against the Laplace nebular hypothesis and published a comprehensive 'planetesimal theory' of the origin of the solar system in 1905. The Chamberlin-Moulton theory has current as well as historical interest.

PLANETESIMAL AND PROTOPLANET DYNAMICS IN A TURBULENT PROTOPLANETARY DISK: IDEAL UNSTRATIFIED DISKS

International Nuclear Information System (INIS)

Yang, Chao-Chin; Mac Low, Mordecai-Mark; Menou, Kristen

2009-01-01

The dynamics of planetesimals and planetary cores may be strongly influenced by density perturbations driven by magneto-rotational turbulence in their natal protoplanetary gas disks. Using the local shearing box approximation, we perform numerical simulations of planetesimals moving as massless particles in a turbulent, magnetized, unstratified gas disk. Our fiducial disk model shows turbulent accretion characterized by a Shakura-Sunyaev viscosity parameter of α ∼ 10 -2 , with rms density perturbations of ∼10%. We measure the statistical evolution of particle orbital properties in our simulations including mean radius, eccentricity, and velocity dispersion. We confirm random walk growth in time of all three properties, the first time that this has been done with direct orbital integration in a local model. We find that the growth rate increases with the box size used at least up to boxes of eight scale heights in horizontal size. However, even our largest boxes show velocity dispersions sufficiently low that collisional destruction of planetesimals should be unimportant in the inner disk throughout its lifetime. Our direct integrations agree with earlier torque measurements showing that type I migration dominates over diffusive migration by stochastic torques for most objects in the planetary core and terrestrial planet mass range. Diffusive migration remains important for objects in the mass range of kilometer-sized planetesimals. Discrepancies in the derived magnitude of turbulence between local and global simulations of magneto-rotationally unstable disks remains an open issue, with important consequences for planet formation scenarios.

An Empirical Planetesimal Belt Radius–Stellar Luminosity Relation

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Matrà, L.; Marino, S.; Kennedy, G. M.; Wyatt, M. C.; Öberg, K. I.; Wilner, D. J.

2018-05-01

Resolved observations of millimeter-sized dust, tracing larger planetesimals, have pinpointed the location of 26 Edgeworth–Kuiper Belt analogs. We report that a belt’s distance R to its host star correlates with the star’s luminosity L ⋆, following R\\propto {L}\\star 0.19 with a low intrinsic scatter of ∼17%. Remarkably, our Edgeworth–Kuiper Belt in the solar system and the two CO snow lines imaged in protoplanetary disks lie close to this R–L ⋆ relation, suggestive of an intrinsic relationship between protoplanetary disk structures and belt locations. To test the effect of bias on the relation, we use a Monte Carlo approach and simulate uncorrelated model populations of belts. We find that observational bias could produce the slope and intercept of the R–L ⋆ relation but is unable to reproduce its low scatter. We then repeat the simulation taking into account the collisional evolution of belts, following the steady-state model that fits the belt population as observed through infrared excesses. This significantly improves the fit by lowering the scatter of the simulated R–L ⋆ relation; however, this scatter remains only marginally consistent with the one observed. The inability of observational bias and collisional evolution alone to reproduce the tight relationship between belt radius and stellar luminosity could indicate that planetesimal belts form at preferential locations within protoplanetary disks. The similar trend for CO snow line locations would then indicate that the formation of planetesimals or planets in the outer regions of planetary systems is linked to the volatility of their building blocks, as postulated by planet formation models.

Formation of the terrestrial planets in the solar system around 1 au via radial concentration of planetesimals

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Ogihara, Masahiro; Kokubo, Eiichiro; Suzuki, Takeru K.; Morbidelli, Alessandro

2018-05-01

Context. No planets exist inside the orbit of Mercury and the terrestrial planets of the solar system exhibit a localized configuration. According to thermal structure calculation of protoplanetary disks, a silicate condensation line ( 1300 K) is located around 0.1 au from the Sun except for the early phase of disk evolution, and planetesimals could have formed inside the orbit of Mercury. A recent study of disk evolution that includes magnetically driven disk winds showed that the gas disk obtains a positive surface density slope inside 1 au from the central star. In a region with positive midplane pressure gradient, planetesimals undergo outward radial drift. Aims: We investigate the radial drift of planetesimals and type I migration of planetary embryos in a disk that viscously evolves with magnetically driven disk winds. We show a case in which no planets remain in the close-in region. Methods: Radial drifts of planetesimals are simulated using a recent disk evolution model that includes effects of disk winds. The late stage of planet formation is also examined by performing N-body simulations of planetary embryos. Results: We demonstrate that in the middle stage of disk evolution, planetesimals can undergo convergent radial drift in a magnetorotational instability (MRI)-inactive disk, in which the pressure maximum is created, and accumulate in a narrow ring-like region with an inner edge at 0.7 au from the Sun. We also show that planetary embryos that may grow from the narrow planetesimal ring do not exhibit significant type I migration in the late stage of disk evolution. Conclusions: The origin of the localized configuration of the terrestrial planets of the solar system, in particular the deficit of close-in planets, can be explained by the convergent radial drift of planetesimals in disks with a positive pressure gradient in the close-in region.

Sublimation of icy planetesimals and the delivery of water to the habitable zone around solar type stars

Science.gov (United States)

Brunini, Adrián; López, María Cristina

2018-06-01

We present a semi analytic model to evaluate the delivery of water to the habitable zone around a solar type star carried by icy planetesimals born beyond the snow line. The model includes sublimation of ice, gas drag and scattering by an outer giant planet located near the snow line. The sublimation model is general and could be applicable to planetary synthesis models or N-Body simulations of the formation of planetary systems. We perform a short series of simulations to asses the potential relevance of sublimation of volatiles in the process of delivery of water to the inner regions of a planetary system during early stages of its formation. We could anticipate that erosion by sublimation would prevent the arrival of much water to the habitable zone of protoplanetary disks in the form of icy planetesimals. Close encounters with a massive planet orbiting near the outer edge of the snow line could make possible for planetesimals to reach the habitable zone somewhat less eroded. However, only large planetesimals could provide appreciable amounts of water. Massive disks and sharp gas surface density profiles favor icy planetesimals to reach inner regions of a protoplanetary disk.

Erosion and the limits to planetesimal growth

Science.gov (United States)

Krijt, S.; Ormel, C. W.; Dominik, C.; Tielens, A. G. G. M.

2015-02-01

Context. The coagulation of microscopic dust into planetesimals is the first step towards the formation of planets. The composition, size, and shape of the growing aggregates determine the efficiency of this early growth. In particular, it has been proposed that fluffy ice aggregates can grow very efficiently in protoplanetary disks, suffering less from the bouncing and radial drift barriers. Aims: While the collision velocity between icy aggregates of similar size is thought to stay below the fragmentation threshold, they may nonetheless lose mass from collisions with much smaller projectiles. As a result, erosive collisions have the potential to terminate the growth of pre-planetesimal bodies. We investigate the effect of these erosive collisions on the ability of porous ice aggregates to cross the radial drift barrier. Methods: We develop a Monte Carlo code that calculates the evolution of the masses and porosities of growing aggregates, while resolving the entire mass distribution at all times. The aggregate's porosity is treated independently of its mass, and is determined by collisional compaction, gas compaction, and eventually self-gravity compaction. We include erosive collisions and study the effect of the erosion threshold velocity on aggregate growth. Results: For erosion threshold velocities of 20-40 m s-1, high-velocity collisions with small projectiles prevent the largest aggregates from growing when they start to drift. In these cases, our local simulations result in a steady-state distribution, with most of the dust mass in particles with Stokes numbers close to unity. Only for the highest erosion threshold considered (60 m s-1) do porous aggregates manage to cross the radial drift barrier in the inner 10 AU of MMSN-like disks. Conclusions: Erosive collisions are more effective in limiting the growth than fragmentary collisions between similar-size particles. Conceivably, erosion limits the growth before the radial drift barrier, although the

Dust Evolution in Protoplanetary Discs and the Formation of Planetesimals. What Have We Learned from Laboratory Experiments?

Science.gov (United States)

Blum, Jürgen

2018-03-01

After 25 years of laboratory research on protoplanetary dust agglomeration, a consistent picture of the various processes that involve colliding dust aggregates has emerged. Besides sticking, bouncing and fragmentation, other effects, like, e.g., erosion or mass transfer, have now been extensively studied. Coagulation simulations consistently show that μm-sized dust grains can grow to mm- to cm-sized aggregates before they encounter the bouncing barrier, whereas sub-μm-sized water-ice particles can directly grow to planetesimal sizes. For siliceous materials, other processes have to be responsible for turning the dust aggregates into planetesimals. In this article, these processes are discussed, the physical properties of the emerging dusty or icy planetesimals are presented and compared to empirical evidence from within and without the Solar System. In conclusion, the formation of planetesimals by a gravitational collapse of dust "pebbles" seems the most likely.

Impact splash chondrule formation during planetesimal recycling

OpenAIRE

Lichtenberg, Tim; Golabek, Gregor J.; Dullemond, Cornelis P.; Schönbächler, Maria; Gerya, Taras V.; Meyer, Michael R.

2017-01-01

Chondrules are the dominant bulk silicate constituent of chondritic meteorites and originate from highly energetic, local processes during the first million years after the birth of the Sun. So far, an astrophysically consistent chondrule formation scenario, explaining major chemical, isotopic and textural features, remains elusive. Here, we examine the prospect of forming chondrules from planetesimal collisions. We show that intensely melted bodies with interior magma oceans became rapidly c...

Planetesimal core formation with partial silicate melting using in-situ high P, high T, deformation x-ray microtomography

Science.gov (United States)

Anzures, B. A.; Watson, H. C.; Yu, T.; Wang, Y.

2017-12-01

Differentiation is a defining moment in formation of terrestrial planets and asteroids. Smaller planetesimals likely didn't reach high enough temperatures for widescale melting. However, we infer that core formation must have occurred within a few million years from Hf-W dating. In lieu of a global magma ocean, planetesimals likely formed through inefficient percolation. Here, we used in-situ high temperature, high pressure, x-ray microtomography to track the 3-D evolution of the sample at mantle conditions as it underwent shear deformation. Lattice-Boltzmann simulations for permeability were used to characterize the efficiency of melt percolation. Mixtures of KLB1 peridotite plus 6.0 to 12.0 vol% FeS were pre-sintered to achieve an initial equilibrium microstructure, and then imaged through several consecutive cycles of heating and deformation. The maximum calculated melt segregation velocity was found to be 0.37 cm/yr for 6 vol.% FeS and 0.61 cm/year for 12 vol.% FeS, both below the minimum velocity of 3.3 cm/year required for a 100km planetesimal to fully differentiate within 3 million years. However, permeability is also a function of grain size and thus the samples having smaller grains than predicted for small planetesimals could have contributed to low permeability and also low migration velocity. The two-phase (sulfide melt and silicate melt) flow at higher melt fractions (6 vol.% and 12 vol.% FeS) was an extension of a similar study1 containing only sulfide melt at lower melt fraction (4.5 vol.% FeS). Contrary to the previous study, deformation did result in increased permeability until the sample was sheared by twisting the opposing Drickamer anvils by 360 degrees. Also, the presence of silicate melt caused the FeS melt to coalesce into less connected pathways as the experiment with 6 vol.% FeS was found to be less permeable than the one with 4.5 vol.% FeS but without any partial melt. The preliminary data from this study suggests that impacts as well as

Abstracts of contributed papers

Energy Technology Data Exchange (ETDEWEB)

1994-08-01

This volume contains 571 abstracts of contributed papers to be presented during the Twelfth US National Congress of Applied Mechanics. Abstracts are arranged in the order in which they fall in the program -- the main sessions are listed chronologically in the Table of Contents. The Author Index is in alphabetical order and lists each paper number (matching the schedule in the Final Program) with its corresponding page number in the book.

ZEUS contributed papers to CHEP92

International Nuclear Information System (INIS)

1992-10-01

At the Computing in High Energy Physics conference, CHEP92 Annecy 21st - 25th September 1992, the ZEUS data acquisition groups contributed a number of papers, as a result of plenary, parallel and poster session contributions. These papers are appended after the index list and a figure which gives a schematic overview of the acquisition system. The papers give up-to-date information concerning the ZEUS data acquisition system and the experience gained during the first HERA running period in 1992. (orig.)

Synthesis of Amino Acid Precursors with Organic Solids in Planetesimals with Liquid Water

Science.gov (United States)

Kebukawa, Y.; Chan, Q. H. S.; Misawa, S.; Matsukuma, J.; Tachibana, S.; Kobayashi, K.; Zolensky, M. E.

2017-07-01

We demonstrated synthesis of a complex suite of amino acids simultaneously with IOM via hydrothermal experiments starting from formaldehyde, glycolaldehyde and ammonia, simulating the aqueous processing in the planetesimals.

THE ROLE OF PEBBLE FRAGMENTATION IN PLANETESIMAL FORMATION. I. EXPERIMENTAL STUDY

Energy Technology Data Exchange (ETDEWEB)

Syed, M. Bukhari; Blum, J. [Institut für Geophysik und extraterrestrische Physik, Technische Universität zu Braunschweig, Mendelssohnstr. 3, D-38106 Braunschweig (Germany); Jansson, K. Wahlberg; Johansen, A. [Lund Observatory, Department of Astronomy and Theoretical Physics, Lund University, Box 43, SE-221 00 Lund (Sweden)

2017-01-10

Previous work on protoplanetary dust growth shows a halt at centimeter sizes owing to the occurrence of bouncing at velocities of ≳0.1 m s{sup −1} and fragmentation at velocities ≳1 m s{sup −1}. To overcome these barriers, spatial concentration of centimeter-sized dust pebbles and subsequent gravitational collapse have been proposed. However, numerical investigations have shown that dust aggregates may undergo fragmentation during the gravitational collapse phase. This fragmentation in turn changes the size distribution of the solids and thus must be taken into account in order to understand the properties of the planetesimals that form. To explore the fate of dust pebbles undergoing fragmenting collisions, we conducted laboratory experiments on dust-aggregate collisions with a focus on establishing a collision model for this stage of planetesimal formation. In our experiments, we analyzed collisions of dust aggregates with masses between 0.7 and 91 g mass ratios between target and projectile from 1 to 126 at a fixed porosity of 65%, within the velocity range of 1.5–8.7 m s{sup −1}, at low atmospheric pressure of ∼10{sup −3} mbar, and in free-fall conditions. We derived the mass of the largest fragment, the fragment size/mass distribution, and the efficiency of mass transfer as a function of collision velocity and projectile/target aggregate size. Moreover, we give recipes for an easy-to-use fragmentation and mass-transfer model for further use in modeling work. In a companion paper, we use the experimental findings and the derived dust-aggregate collision model to investigate the fate of dust pebbles during gravitational collapse.

Coagulation calculations of icy planet formation around 0.1-0.5 M {sub ☉} stars: Super-Earths from large planetesimals

Energy Technology Data Exchange (ETDEWEB)

Kenyon, Scott J. [Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States); Bromley, Benjamin C., E-mail: skenyon@cfa.harvard.edu, E-mail: bromley@physics.utah.edu [Department of Physics, University of Utah, 201 JFB, Salt Lake City, UT 84112 (United States)

2014-01-01

We investigate formation mechanisms for icy super-Earth-mass planets orbiting at 2-20 AU around 0.1-0.5 M {sub ☉} stars. A large ensemble of coagulation calculations demonstrates a new formation channel: disks composed of large planetesimals with radii of 30-300 km form super-Earths on timescales of ∼1 Gyr. In other gas-poor disks, a collisional cascade grinds planetesimals to dust before the largest planets reach super-Earth masses. Once icy Earth-mass planets form, they migrate through the leftover swarm of planetesimals at rates of 0.01-1 AU Myr{sup –1}. On timescales of 10 Myr to 1 Gyr, many of these planets migrate through the disk of leftover planetesimals from semimajor axes of 5-10 AU to 1-2 AU. A few percent of super-Earths might migrate to semimajor axes of 0.1-0.2 AU. When the disk has an initial mass comparable with the minimum-mass solar nebula, scaled to the mass of the central star, the predicted frequency of super-Earths matches the observed frequency.

X-ray photoevaporation's limited success in the formation of planetesimals by the streaming instability

Science.gov (United States)

Ercolano, Barbara; Jennings, Jeff; Rosotti, Giovanni; Birnstiel, Tilman

2017-12-01

The streaming instability is often invoked as solution to the fragmentation and drift barriers in planetesimal formation, catalysing the aggregation of dust on kyr time-scales to grow km-sized cores. However, there remains a lack of consensus on the physical mechanism(s) responsible for initiating it. One potential avenue is disc photoevaporation, wherein the preferential removal of relatively dust-free gas increases the disc metallicity. Late in the disc lifetime, photoevaporation dominates viscous accretion, creating a gradient in the depleted gas surface density near the location of the gap. This induces a local pressure maximum that collects drifting dust particles, which may then become susceptible to the streaming instability. Using a one-dimensional viscous evolution model of a disc subject to internal X-ray photoevaporation, we explore the efficacy of this process to build planetesimals. Over a range of parameters, we find that the amount of dust mass converted into planetesimals is often planetary cores. Our results are in contrast to a recent, similar investigation that considered an far-ultra-violet (FUV)-driven photoevaporation model and reported the formation of tens of M⊕ at large (>100 au) disc radii. The discrepancies are primarily a consequence of the different photoevaporation profiles assumed. Until observations more tightly constrain photoevaporation models, the relevance of this process to the formation of planets remains uncertain.

Paleomagnetic evidence for a partially differentiated H chondrite parent planetesimal

Science.gov (United States)

Bryson, J. F. J.; Weiss, B. P.; Scholl, A.; Getzin, B. L.; Abrahams, J. N. H.; Nimmo, F.

2016-12-01

ages of various H chondrites (Abrahams et al., this meeting). These observations contribute to a growing body of evidence supporting a spectrum of differentiation within planetesimals and place crucial constraints on the thermochemical evolution and formation of chondrite parent bodies.

Redox States of Initial Atmospheres Outgassed on Rocky Planets and Planetesimals

Energy Technology Data Exchange (ETDEWEB)

Schaefer, Laura [Arizona State University, School of Earth and Space Exploration, Tempe, AZ 85287 (United States); Fegley, Bruce Jr., E-mail: lschaefer@asu.edu [Planetary Chemistry Laboratory, Department of Earth and Planetary Sciences, Washington University, St. Louis, MO 63130 (United States)

2017-07-10

The Earth and other rocky planets and planetesimals in the solar system formed through the mixing of materials from various radial locations in the solar nebula. This primordial material likely had a range of oxidation states as well as bulk compositions and volatile abundances. We investigate the oxygen fugacity produced by the outgassing of mixtures of solid meteoritic material, which approximate the primitive nebular materials. We find that the gas composition and oxygen fugacity of binary and ternary mixtures of meteoritic materials vary depending on the proportion of reduced versus oxidized material, and also find that mixtures using differentiated materials do not show the same oxygen fugacity trends as those using similarly reduced but undifferentiated materials. We also find that simply mixing the gases produced by individual meteoritic materials together does not correctly reproduce the gas composition or oxygen fugacity of the binary and ternary mixtures. We provide tabulated fits for the oxygen fugacities of all of the individual materials and binary mixtures that we investigate. These values may be useful in planetary formation models, models of volatile transport on planetesimals or meteorite parent bodies, or models of trace element partitioning during metal-silicate fractionation.

Planetesimals early differentiation and consequences for planets

CERN Document Server

Weiss, Benjamin P

2017-01-01

Processes governing the evolution of planetesimals are critical to understanding how rocky planets are formed, how water is delivered to them, the origin of planetary atmospheres, how cores and magnetic dynamos develop, and ultimately, which planets have the potential to be habitable. Theoretical advances and new data from asteroid and meteorite observations, coupled with spacecraft missions such as Rosetta and Dawn, have led to major advances in this field over the last decade. This transdisciplinary volume presents an authoritative overview of the latest in our understanding of the processes of planet formation. Combining meteorite, asteroid and icy body observations with theory and modelling of accretion and orbital dynamics, this text also provides insights into the exoplanetary system and the search for habitable worlds. This is an essential reference for those interested in planetary formation, solar system dynamics, exoplanets and planetary habitability.

Planetesimal Formation in the Warm, Inner Disk: Experiments with Tempered Dust

Energy Technology Data Exchange (ETDEWEB)

De Beule, Caroline; Landers, Joachim; Salamon, Soma; Wende, Heiko; Wurm, Gerhard, E-mail: gerhard.wurm@uni-due.de [Faculty of Physics, University of Duisburg-Essen, Lotharstr. 1, D-47057 Duisburg (Germany)

2017-03-01

It is an open question how elevated temperatures in the inner parts of protoplanetary disks influence the formation of planetesimals. We approach this problem here by studying the tensile strength of granular beds with dust samples tempered at different temperatures. We find via laboratory experiments that tempering at increasing temperatures is correlated with an increase in cohesive forces. We studied dust samples of palagonite (JSC Mars-1a) which were tempered for up to 200 hr at temperatures between 600 and 1200 K, and measured the relative tensile strengths of highly porous dust layers once the samples cooled to room temperature. Tempering increases the tensile strength from 800 K upwards. This change is accompanied by mineral transformations, the formation of iron oxide crystallites as analyzed by Mössbauer spectroscopy, changes in the number size distribution, and the morphology of the surface visible as cracks in larger grains. These results suggest a difference in the collisional evolution toward larger bodies with increasing temperature as collisional growth is fundamentally based on cohesion. While high temperatures might also increase sticking (not studied here), compositional evolution will already enhance the cohesion and the possibility of growing larger aggregates on the way toward planetesimals. This might lead to a preferred in situ formation of inner planets and explain the observed presence of dense inner planetary systems.

PLANET-PLANET SCATTERING IN PLANETESIMAL DISKS. II. PREDICTIONS FOR OUTER EXTRASOLAR PLANETARY SYSTEMS

International Nuclear Information System (INIS)

Raymond, Sean N.; Armitage, Philip J.; Gorelick, Noel

2010-01-01

We develop an idealized dynamical model to predict the typical properties of outer extrasolar planetary systems, at radii comparable to the Jupiter-to-Neptune region of the solar system. The model is based upon the hypothesis that dynamical evolution in outer planetary systems is controlled by a combination of planet-planet scattering and planetary interactions with an exterior disk of small bodies ('planetesimals'). Our results are based on 5000 long duration N-body simulations that follow the evolution of three planets from a few to 10 AU, together with a planetesimal disk containing 50 M + from 10 to 20 AU. For large planet masses (M ∼> M Sat ), the model recovers the observed eccentricity distribution of extrasolar planets. For lower-mass planets, the range of outcomes in models with disks is far greater than that which is seen in isolated planet-planet scattering. Common outcomes include strong scattering among massive planets, sudden jumps in eccentricity due to resonance crossings driven by divergent migration, and re-circularization of scattered low-mass planets in the outer disk. We present the distributions of the eccentricity and inclination that result, and discuss how they vary with planet mass and initial system architecture. In agreement with other studies, we find that the currently observed eccentricity distribution (derived primarily from planets at a ∼ -1 and periods in excess of 10 years will provide constraints on this regime. Finally, we present an analysis of the predicted separation of planets in two-planet systems, and of the population of planets in mean-motion resonances (MMRs). We show that, if there are systems with ∼ Jupiter-mass planets that avoid close encounters, the planetesimal disk acts as a damping mechanism and populates MMRs at a very high rate (50%-80%). In many cases, resonant chains (in particular the 4:2:1 Laplace resonance) are set up among all three planets. We expect such resonant chains to be common among massive

Formation of planetesimals in the Solar Nebula

Science.gov (United States)

Hueso, R.; Guillot, T.

2001-11-01

We study the evolution of protoplanetary disks with gas and embedded particles using a classical alpha-disk model. Solid matter entrained in the gas is incorporated following the formalism of Stepinski and Valageas (A&A, 1996, 1997). Dust grains coagulate into larger particles until they eventually decouple from the gas. The coagulation process is modulated by the evaporation and condensation of dust in the disk. We simultaneously consider grains of ices and rock, which allows us to study the amount of different solid material available to form the different planets. In particular, we present consequences for the development of planetesimals in the Uranus and Neptune region. This is interesting in the light of interior models of these planets, which naturally tend to predict a low rock to ice ratio. We will also discuss the consequences of these results on the standard core-accretion formation scenario. Acknowledgements: This work has been supported by Programme National du Planetologie. R. Hueso acknowledges a post-doctoral fellowship from Gobierno Vasco.

Planetesimal formation by sweep-up coagulation

Science.gov (United States)

Windmark, Fredrik; Birnstiel, Til; Ormel, Chris W.; Dullemond, Cornelis P.

2013-07-01

The formation of planetesimals is often accredited to collisional sticking of dust grains in the protoplanetary disk. The exact process is however unknown, as collisions between larger aggregates tend to lead to fragmentation or bouncing rather than sticking. These growth barriers tend to halt the dust growth already at millimeters or centimeters in size, which is far below the kilometer-sizes that are needed for gravity to aid in the accretion. To study how far dust coagulation can proceed, we have developed a new collision model based on the latest laboratory experiments, and have used it together with a dust-size evolution code capable of resolving all grain interactions in the protoplanetary disk. We find that for the general dust population, bouncing and fragmenting collisions prevent the growth above millimeter-sizes. However, a small number of lucky particles can grow larger than the rest by only interacting at low, sticky velocities. As they grow, they become increasingly resilient to fragmentation caused by the small grains. In this way, two populations are formed: One which remains small due to the collisional barriers, and one that continues to grow by sweeping up the smaller grains around them.

Recycling of paper: accounting of greenhouse gases and global warming contributions.

Science.gov (United States)

Merrild, Hanna; Damgaard, Anders; Christensen, Thomas H

2009-11-01

Greenhouse gas (GHG) emissions have been established for recycling of paper waste with focus on a material recovery facility (MRF). The MRF upgrades the paper and cardboard waste before it is delivered to other industries where new paper or board products are produced. The accounting showed that the GHG contributions from the upstream activities and operational activities, with global warming factors (GWFs) of respectively 1 to 29 and 3 to 9 kg CO(2)-eq. tonne(- 1) paper waste, were small in comparison wih the downstream activities. The GHG contributions from the downstream reprocessing of the paper waste ranged from approximately 490 to 1460 kg CO(2)-eq. tonne( -1) of paper waste. The system may be expanded to include crediting of avoided virgin paper production which would result in GHG contributions from -1270 to 390 kg CO(2)-eq. tonne(- 1) paper waste. It may also be assumed that the wood not used for virgin paper production instead is used for production of energy that in turn is assumed to substitute for fossil fuel energy. This would result in GHG contributions from -1850 to -4400 kg CO(2)-eq. tonne(- 1) of paper waste. These system expansions reveal very large GHG savings, suggesting that the indirect upstream and operational GHG contributions are negligible in comparison with the indirect downstream emissions. However, the data for reprocessing of paper waste and the data for virgin paper production are highly variable. These differences are mainly related to different energy sources for the mills, both in regards to energy form (heat or electricity) and fuel (biomass or fossil fuels).

Migration of planetesimals during last stages of giant planet accumulation

International Nuclear Information System (INIS)

Ipatov, S.I.

1989-01-01

The migration and accumulation of bodies from the giant planet's feeding zones are investigated after the main part of mass of these planets had been formed. These investigations are based on the computer simulation results for the evolving spatial disks which initially consisted of a few almost formed planets and hundreds of identical bodies in Uranus and Neptune zone. It is shown that the total mass of bodies penetrated in the asteroid zone from the giant planet zones could be ten times as large as the Earth mass. The beyond-Neptune belt could form during accumulation of the giant planets. Evolution of the planet orbits under encounters of planets with planetesimals is investigated

Formation of Non-symmetric Fractals During the First Stage of Pre-planetesimal Dust Growth

Science.gov (United States)

Kempf, S.; Blum, J.; Wurm, G.

It is a generally accepted view that the genesis of a planetary system coincide s with the formation of sun-like young stellar objects surrounded by gaseous disc s. The building blocks of the planetesimals are micron-sized solid particles (the so-called dust) embedded in the gas of the disc. The relevant process for formi ng larger aggregates is the growth due to collisional sticking. For particles to c ollide and stick, a relative velocity component between the grains must be present. In the onset of dust growth, Brownian motion dominates other relative-velocity sources . However, numerically determined time scales of the pure Brownian dust growth are much too large for explaining the formation of planets within the lifetime of a proto-planetary di sc. In order to verify the validity of the theoretical models, the Cosmic Dust Aggr egation Experiment CODAG was developed. It allows to observe the growth of micron-sized dust analogs under astrophysical realistic conditions. Surprisingly, the experi ments showed that at least in the onset of the dust growth needle-like fractal aggreg ates rather than symmetric fractals are formed. Here we discuss the implication of this experimental finding for the pre-planetesimal growth models.

Recycling of paper: Accounting of greenhouse gases and global warming contributions

DEFF Research Database (Denmark)

Merrild, Hanna Kristina; Damgaard, Anders; Christensen, Thomas Højlund

2009-01-01

that the GHG contributions from the upstream activities and operational activities, with global warming factors (GWFs) of respectively 1 to 29 and 3 to 9 kg CO2-eq. tonne— 1 paper waste, were small in comparison wih the downstream activities. The GHG contributions from the downstream reprocessing of the paper...

Investigating Planetesimal Evolution by Experiments with Fe-Ni Metallic Melts: Light Element Composition Effects on Trace Element Partitioning Behavior

Science.gov (United States)

Chabot, N. L.

2017-12-01

As planetesimals were heated up in the early Solar System, the formation of Fe-Ni metallic melts was a common occurrence. During planetesimal differentiation, the denser Fe-Ni metallic melts separated from the less dense silicate components, though some meteorites suggest that their parent bodies only experienced partial differentiation. If the Fe-Ni metallic melts did form a central metallic core, the core eventually crystallized to a solid, some of which we sample as iron meteorites. In all of these planetesimal evolution processes, the composition of the Fe-Ni metallic melt influenced the process and the resulting trace element chemical signatures. In particular, the metallic melt's "light element" composition, those elements present in the metallic melt in a significant concentration but with lower atomic masses than Fe, can strongly affect trace element partitioning. Experimental studies have provided critical data to determine the effects of light elements in Fe-Ni metallic melts on trace element partitioning behavior. Here I focus on combining numerous experimental results to identify trace elements that provide unique insight into constraining the light element composition of early Solar System Fe-Ni metallic melts. Experimental studies have been conducted at 1 atm in a variety of Fe-Ni systems to investigate the effects of light elements on trace element partitioning behavior. A frequent experimental examination of the effects of light elements in metallic systems involves producing run products with coexisting solid metal and liquid metal phases. Such solid-metal-liquid-metal experiments have been conducted in the Fe-Ni binary system as well as Fe-Ni systems with S, P, and C. Experiments with O-bearing or Si-bearing Fe-Ni metallic melts do not lend themselves to experiments with coexisting solid metal and liquid metal phases, due to the phase diagrams of these elements, but experiments with two immiscible Fe-Ni metallic melts have provided insight into

GRAVOTURBULENT PLANETESIMAL FORMATION: THE POSITIVE EFFECT OF LONG-LIVED ZONAL FLOWS

International Nuclear Information System (INIS)

Dittrich, K.; Klahr, H.; Johansen, A.

2013-01-01

Recent numerical simulations have shown long-lived axisymmetric sub- and super-Keplerian flows in protoplanetary disks. These zonal flows are found in local as well as global simulations of disks unstable to the magnetorotational instability. This paper covers our study of the strength and lifetime of zonal flows and the resulting long-lived gas over- and underdensities as functions of the azimuthal and radial size of the local shearing box. We further investigate dust particle concentrations without feedback on the gas and without self-gravity. The strength and lifetime of zonal flows increase with the radial extent of the simulation box, but decrease with the azimuthal box size. Our simulations support earlier results that zonal flows have a natural radial length scale of 5-7 gas pressure scale heights. This is the first study that combines three-dimensional MHD simulations of zonal flows and dust particles feeling the gas pressure. The pressure bumps trap particles with St = 1 very efficiently. We show that St = 0.1 particles (of some centimeters in size if at 5 AU in a minimum mass solar nebula) reach a hundred-fold higher density than initially. This opens the path for particles of St = 0.1 and dust-to-gas ratio of 0.01 or for particles of St ≥ 0.5 and dust-to-gas ratio 10 –4 to still reach densities that potentially trigger the streaming instability and thus gravoturbulent formation of planetesimals.

International conference on the safety of radioactive waste management. Contributed papers

International Nuclear Information System (INIS)

2000-03-01

This book contains 104 contributed papers submitted on issues falling within the thematic scope of the Conference. The papers present technical and regulatory approaches and practices on safety in spent nuclear fuel and radioactive waste management including storage, processing and final disposal. Each of the papers was individually indexed and provided with an abstract

International conference on the safety of radioactive waste management. Contributed papers

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

This book contains 104 contributed papers submitted on issues falling within the thematic scope of the Conference. The papers present technical and regulatory approaches and practices on safety in spent nuclear fuel and radioactive waste management including storage, processing and final disposal. Each of the papers was individually indexed and provided with an abstract.

The nursing contribution to chronic disease management: a discussion paper.

Science.gov (United States)

Forbes, Angus; While, Alison

2009-01-01

This paper explores the nature of the nursing contribution to chronic disease management (CDM) and identifies a number of key nursing activities within CDM both at the individual patient and care system levels. The activities were identified following a detailed review of the literature (160 reports and studies of nursing practice) relating to three tracer disorders: diabetes, chronic obstructive pulmonary disease and multiple sclerosis. The paper examines these activities collectively to generate models expressing some of the core functions of nursing within CDM. The paper illustrates some of the changing characteristics of nursing roles within CDM. More fundamentally, the paper questions the position of nursing in relation to the technologies that define CDM systems and proposes four levels of contribution: the nurse as technology; the nurse as technologist; the nurse as system engineer; and the nurse as architect. These different levels reflect distinctions in the nature of the nursing gaze and power relations within the health care workforce. The paper also highlights how nurses are failing to develop the evidence for their practice in CDM. The paper concludes that there is a need for some clear principles to guide clinical practice and encourage innovation in CDM. It is argued that the principles should not be rule-bound but define a distinctive nursing gaze that will position the nursing profession within the health care system and in relation to other professions. The gaze should incorporate the needs of the individual patient and the care system that they inhabit.

Synthesis of Amino Acid Precursors with Organic Solids in Planetesimals with Liquid Water

Science.gov (United States)

Kebukawa, Y; Misawa, S.; Matsukuma, J.; Chan, Q. H. S.; Kobayashi, J.; Tachibana, S.; Zolensky, M. E.

2017-01-01

Amino acids are important ingredients of life that would have been delivered to Earth by extraterrestrial sources, e.g., comets and meteorites. Amino acids are found in aqueously altered carbonaceous chondrites in good part in the form of precursors that release amino acids after acid hydrolysis. Meanwhile, most of the organic carbon (greater than 70 weight %) in carbonaceous chondrites exists in the form of solvent insoluble organic matter (IOM) with complex macromolecular structures. Complex macromolecular organic matter can be produced by either photolysis of interstellar ices or aqueous chemistry in planetesimals. We focused on the synthesis of amino acids during aqueous alteration, and demonstrated one-pot synthesis of a complex suite of amino acids simultaneously with IOM via hydrothermal experiments simulating the aqueous processing

SMACK: A New Algorithm for Modeling Collisions and Dynamics of Planetesimals in Debris Disks

Science.gov (United States)

Nesvold, Erika Rose; Kuchner, Marc J.; Rein, Hanno; Pan, Margaret

2013-01-01

We present the Superparticle Model/Algorithm for Collisions in Kuiper belts and debris disks (SMACK), a new method for simultaneously modeling, in 3-D, the collisional and dynamical evolution of planetesimals in a debris disk with planets. SMACK can simulate azimuthal asymmetries and how these asymmetries evolve over time. We show that SMACK is stable to numerical viscosity and numerical heating over 10(exp 7) yr, and that it can reproduce analytic models of disk evolution. We use SMACK to model the evolution of a debris ring containing a planet on an eccentric orbit. Differential precession creates a spiral structure as the ring evolves, but collisions subsequently break up the spiral, leaving a narrower eccentric ring.

Planetesimal formation by an axisymmetric radial bump of the column density of the gas in a protoplanetary disk

Science.gov (United States)

Onishi, Isamu K.; Sekiya, Minoru

2017-04-01

We investigate the effect of a radial pressure bump in a protoplanetary disk on planetesimal formation. We performed the two-dimensional numerical simulation of the dynamical interaction of solid particles and gas with an initially defined pressure bump under the assumption of axisymmetry. The aim of this work is to elucidate the effects of the stellar vertical gravity that were omitted in a previous study. Our results are very different from the previous study, which omitted the vertical gravity. Because dust particles settle toward the midplane because of the vertical gravity to form a thin dust layer, the regions outside of the dust layer are scarcely affected by the back-reaction of the dust. Hence, the gas column density keeps its initial profile with a bump, and dust particles migrate toward the bump. In addition, the turbulence due to the Kelvin-Helmholtz instability caused by the difference of the azimuthal velocities between the inside and outside of the dust layer is suppressed where the radial pressure gradient is reduced by the pressure bump. The dust settling proceeds further where the turbulence is weak, and a number of dust clumps are formed. The dust density in some clumps exceeds the Roche density. Planetesimals are considered to be formed from these clumps owing to the self-gravity.[Figure not available: see fulltext.

Fourth Latin-American workshop on plasma physics. Contributed papers

International Nuclear Information System (INIS)

1990-01-01

The main goal of this series of Workshops is to provide a periodic meeting place for Latin-American researchers in plasma physics together with colleagues from other countries around the world. This volume includes the contributed papers presented at the Workshop on Plasma Physics held in Buenos Aires in 1990. The scope of the Workshop can be synthesized in the following main subjects: Tokamak experiments and theory; alternative confinement systems and basic experiments; technology and applications; general theory; astrophysical and space plasmas

The Dynamics and Implications of Gap Clearing via Planets in Planetesimal (Debris) Disks

Science.gov (United States)

Morrison, Sarah Jane

Exoplanets and debris disks are examples of solar systems other than our own. As the dusty reservoirs of colliding planetesimals, debris disks provide indicators of planetary system evolution on orbital distance scales beyond those probed by the most prolific exoplanet detection methods, and on timescales 10 r to 10 Gyr. The Solar System possesses both planets and small bodies, and through studying the gravitational interactions between both, we gain insight into the Solar System's past. As we enter the era of resolved observations of debris disks residing around other stars, I add to our theoretical understanding of the dynamical interactions between debris, planets, and combinations thereof. I quantify how single planets clear material in their vicinity and how long this process takes for the entire planetary mass regime. I use these relationships to assess the lowest mass planet that could clear a gap in observed debris disks over the system's lifetime. In the distant outer reaches of gaps in young debris systems, this minimum planet mass can exceed Neptune's. To complement the discoveries of wide-orbit, massive, exoplanets by direct imaging surveys, I assess the dynamical stability of high mass multi-planet systems to estimate how many high mass planets could be packed into young, gapped debris disks. I compare these expectations to the planet detection rates of direct imaging surveys and find that high mass planets are not the primary culprits for forming gaps in young debris disk systems. As an alternative model for forming gaps in planetesimal disks with planets, I assess the efficacy of creating gaps with divergently migrating pairs of planets. I find that migrating planets could produce observed gaps and elude detection. Moreover, the inferred planet masses when neglecting migration for such gaps could be expected to be observable by direct imaging surveys for young, nearby systems. Wide gaps in young systems would likely still require more than two

Silicon isotopes in angrites and volatile loss in planetesimals

Science.gov (United States)

Moynier, Frédéric; Savage, Paul S.; Badro, James; Barrat, Jean-Alix

2014-01-01

Inner solar system bodies, including the Earth, Moon, and asteroids, are depleted in volatile elements relative to chondrites. Hypotheses for this volatile element depletion include incomplete condensation from the solar nebula and volatile loss during energetic impacts. These processes are expected to each produce characteristic stable isotope signatures. However, processes of planetary differentiation may also modify the isotopic composition of geochemical reservoirs. Angrites are rare meteorites that crystallized only a few million years after calcium–aluminum-rich inclusions and exhibit extreme depletions in volatile elements relative to chondrites, making them ideal samples with which to study volatile element depletion in the early solar system. Here we present high-precision Si isotope data that show angrites are enriched in the heavy isotopes of Si relative to chondritic meteorites by 50–100 ppm/amu. Silicon is sufficiently volatile such that it may be isotopically fractionated during incomplete condensation or evaporative mass loss, but theoretical calculations and experimental results also predict isotope fractionation under specific conditions of metal–silicate differentiation. We show that the Si isotope composition of angrites cannot be explained by any plausible core formation scenario, but rather reflects isotope fractionation during impact-induced evaporation. Our results indicate planetesimals initially formed from volatile-rich material and were subsequently depleted in volatile elements during accretion. PMID:25404309

International conference on issues and trends in radioactive waste management. Contributed papers

International Nuclear Information System (INIS)

2002-01-01

This publication contains 78 contributed papers submitted on issues falling within the thematic scope of the Conference which were accepted by the Conference Programme Committee for consideration at the conference. The papers are grouped into the following chapters: control of discharges, environmental aspects; long-term storage; geological disposal; management of radioactive waste, including sealed sources; management of radioactive waste from past eras; regulatory infrastructure, decision making, stakeholders; retention of information, long-term control, standards; specific studies; and international co-operative efforts. Each of the papers was indexed separately

International conference on issues and trends in radioactive waste management. Contributed papers

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-07-01

This publication contains 78 contributed papers submitted on issues falling within the thematic scope of the Conference which were accepted by the Conference Programme Committee for consideration at the conference. The papers are grouped into the following chapters: control of discharges, environmental aspects; long-term storage; geological disposal; management of radioactive waste, including sealed sources; management of radioactive waste from past eras; regulatory infrastructure, decision making, stakeholders; retention of information, long-term control, standards; specific studies; and international co-operative efforts. Each of the papers was indexed separately.

International conference on nuclear security: Global directions for the future. Contributed papers

International Nuclear Information System (INIS)

2005-01-01

This volume includes contributed papers presented during sessions named as follows: Efforts to strengthen the global security framework, Efforts to strengthen nuclear security in Member states, role of the IAEA underpinning the global efforts, and looking forward: sustaining progress

International conference on nuclear security: Global directions for the future. Contributed papers

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-07-01

This volume includes contributed papers presented during sessions named as follows: Efforts to strengthen the global security framework, Efforts to strengthen nuclear security in Member states, role of the IAEA underpinning the global efforts, and looking forward: sustaining progress.

International conference on topical issues in nuclear safety. Contributed papers

International Nuclear Information System (INIS)

2001-01-01

The objective of the Conference was to foster the exchange of information on topical issues in nuclear safety, with the aim of consolidating an international consensus on the present status of these issues, priorities for future work, and needs for strengthening international cooperation, including the IAEA recommendations for future activities. This book contains concise contributed papers submitted on issues falling within the thematic scope of the Conference: risk informed decision making, influence of external factors on safety, safety of fuel cycle facilities, safety of research reactors, and safety performance indicators

International conference on topical issues in nuclear safety. Contributed papers

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-07-01

The objective of the Conference was to foster the exchange of information on topical issues in nuclear safety, with the aim of consolidating an international consensus on the present status of these issues, priorities for future work, and needs for strengthening international cooperation, including the IAEA recommendations for future activities. This book contains concise contributed papers submitted on issues falling within the thematic scope of the Conference: risk informed decision making, influence of external factors on safety, safety of fuel cycle facilities, safety of research reactors, and safety performance indicators.

8th international workshop on plasma edge theory in fusion devices. Abstracts of invited and contributed papers

International Nuclear Information System (INIS)

Sipilae, S.K.; Heikkinen, J.A.

2001-01-01

The 8th International Workshop on Plasma Edge Theory in Fusion Devices, held at Dipoli Congress Centre, Espoo, Finland, is organised on behalf of the International Scientific Committee by Helsinki University of Technology and VTT (Technical Research Centre of Finland). Similar to the seven preceding Workshops, it addresses the theory for the boundary layer of magnetically confined fusion plasmas. It reflects the present status of the theory for the edge region of fusion plasmas. Emphasis is placed on the development of theory and of appropriate numerical methods as well as on self-consistent modelling of experimental data (including also empirical elements). The following topics are covered: basic edge plasma theory, models of special phenomena and edge control, and integrated edge plasma modelling. The International Scientific Committee has selected the papers and compiled the scientific programme. All other arrangements have been made by the Local Organising Committee. The Workshop is supported by the European Commission, High-Level Scientific Conferences. This Book of Abstracts contains the scientific programme and the abstracts of the invited and contributed papers. The Workshop has seven invited lectures of 60 minutes duration (including 10 minutes for discussion). In addition, 10 contributed papers were selected for oral presentation of 30 minutes duration (including five minutes for discussion). All oral presentations are given in plenary sessions. The remaining 34 contributed papers are presented as posters in three sessions. The invited lectures and contributed oral papers are presented also as posters. All invited and contributed papers will be refereed and published also as a regular issue of the journal Contributions to Plasma Physics. (orig.)

Magnesium isotope evidence for single stage formation of CB chondrules by colliding planetesimals

DEFF Research Database (Denmark)

Olsen, Mia Bjørg Stolberg; Schiller, Martin; Krot, Alexander N.

2013-01-01

Chondrules are igneous spherical objects preserved in chondritic meteorites and believed to have formed during transient heating events in the solar protoplanetary disk. Chondrules present in the metal-rich CB chondrites show unusual chemical and petrologic features not observed in other chondrit...... planetesimals. The inferred μMg* value of -3.87 ± 0.93 ppm for the CB parent body is significantly lower than the bulk solar system value of 4.5 ± 1.1 ppm inferred from CI chondrites, suggesting that CB chondrites accreted material comprising an early formed Al-free component.......Chondrules are igneous spherical objects preserved in chondritic meteorites and believed to have formed during transient heating events in the solar protoplanetary disk. Chondrules present in the metal-rich CB chondrites show unusual chemical and petrologic features not observed in other chondrite......, indicating substantial suppression of isotopic fractionation during evaporative loss of Mg, possibly due to evaporation at high Mg partial pressure. Thus, the Mg-isotope data of skeletal chondrules from HH237 are consistent with their origin as melts produced in the impact-generated plume of colliding...

Azimuthal asymmetries in the debris disk around HD 61005. A massive collision of planetesimals?

Science.gov (United States)

Olofsson, J.; Samland, M.; Avenhaus, H.; Caceres, C.; Henning, Th.; Moór, A.; Milli, J.; Canovas, H.; Quanz, S. P.; Schreiber, M. R.; Augereau, J.-C.; Bayo, A.; Bazzon, A.; Beuzit, J.-L.; Boccaletti, A.; Buenzli, E.; Casassus, S.; Chauvin, G.; Dominik, C.; Desidera, S.; Feldt, M.; Gratton, R.; Janson, M.; Lagrange, A.-M.; Langlois, M.; Lannier, J.; Maire, A.-L.; Mesa, D.; Pinte, C.; Rouan, D.; Salter, G.; Thalmann, C.; Vigan, A.

2016-06-01

Context. Debris disks offer valuable insights into the latest stages of circumstellar disk evolution, and can possibly help us to trace the outcomes of planetary formation processes. In the age range 10 to 100 Myr, most of the gas is expected to have been removed from the system, giant planets (if any) must have already been formed, and the formation of terrestrial planets may be on-going. Pluto-sized planetesimals, and their debris released in a collisional cascade, are under their mutual gravitational influence, which may result into non-axisymmetric structures in the debris disk. Aims: High angular resolution observations are required to investigate these effects and constrain the dynamical evolution of debris disks. Furthermore, multi-wavelength observations can provide information about the dust dynamics by probing different grain sizes. Methods: Here we present new VLT/SPHERE and ALMA observations of the debris disk around the 40 Myr-old solar-type star HD 61005. We resolve the disk at unprecedented resolution both in the near-infrared (in scattered and polarized light) and at millimeter wavelengths. We perform a detailed modeling of these observations, including the spectral energy distribution. Results: Thanks to the new observations, we propose a solution for both the radial and azimuthal distribution of the dust grains in the debris disk. We find that the disk has a moderate eccentricity (e ~ 0.1) and that the dust density is two times larger at the pericenter compared to the apocenter. Conclusions: With no giant planets detected in our observations, we investigate alternative explanations besides planet-disk interactions to interpret the inferred disk morphology. We postulate that the morphology of the disk could be the consequence of a massive collision between ~1000 km-sized bodies at ~61 au. If this interpretation holds, it would put stringent constraints on the formation of massive planetesimals at large distances from the star. Based on observations

Analysis of Antarctic Ice-Sheet Mass Balance from ICESat Measurements

Science.gov (United States)

Zwally, H. Jay; Li, Jun; Robbins, John; Saba, Jack L.; Yi, Donghui

2011-01-01

If protoplanets formed from 10 to 20 kilometer diameter planetesimals in a runaway accretion process prior to their oligarchic growth into the terrestrial planets, it is only logical to ask where these planetesimals may have formed in order to assess the initial composition of the Earth. We have used Weidenschilling's model for the formation of comets (1997) to calculate an efficiency factor for the formation of planetesimals from the solar nebula, then used this factor to calculate the feeding zones that contribute to material contained within 10, 15 and 20 kilometer diameter planetesimals at 1 A.V. as a function of nebular mass. We find that for all reasonable nebular masses, these planetesimals contain a minimum of 3% water as ice by mass. The fraction of ice increases as the planetesimals increase in size and as the nebular mass decreases, since both factors increase the feeding zones from which solids in the final planetesimals are drawn. Is there really a problem with the current accretion scenario that makes the Earth too dry, or is it possible that the nascent Earth lost significant quantities of water in the final stages of accretion?

International conference on national infrastructures for radiation safety: Towards effective and sustainable systems. Contributed papers

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-07-01

The International Atomic Energy Agency (IAEA), in co-operation with the World Health Organization (WHO), the International Labour Office (ILO), the European Commission (EC), and the OECD Nuclear Energy Agency (NEA), organized the International Conference on National Infrastructures for Radiation Safety: Towards Effective and Sustainable Systems. This book contains contributed papers submitted on pertinent issues, including stakeholder involvement, IAEA Model Projects on Upgrading Radiation Protection Infrastructure, Quality Assurance, education and training, regulatory activities, performance evaluation, source security, and emergency preparedness. The material in this book has not been edited by the IAEA. These contributed papers will be published on a CD ROM as part of the Proceedings of the Conference, along with the invited papers and discussions. The papers are grouped by topical sessions: Stakeholder Involvement in Building and Maintaining National Radiation Safety Infrastructure (National and International); Implementation Experience with The Model Projects (Views From The Countries, Positive and Negative Experiences); Resources and Services (Systematic Approach), Quality Assurance, International Support Of Services; Sustainable Education And Training: Developing Skills (National Systems And Regional Solutions); Needs for Education And Training at The International Level (Including IAEA Programmes Assisting in Establishing Adequate Infrastructures); Authorization, Inspection and Enforcement (Effectiveness and Efficiency Of The Activities Of The Regulatory Bodies), Independence of Regulatory Authorities; Performance Evaluation; Source Security and Emergency Preparedness (Infrastructure Requirements at the International, National And User's Level)

International conference on national infrastructures for radiation safety: Towards effective and sustainable systems. Contributed papers

International Nuclear Information System (INIS)

2003-01-01

The International Atomic Energy Agency (IAEA), in co-operation with the World Health Organization (WHO), the International Labour Office (ILO), the European Commission (EC), and the OECD Nuclear Energy Agency (NEA), organized the International Conference on National Infrastructures for Radiation Safety: Towards Effective and Sustainable Systems. This book contains contributed papers submitted on pertinent issues, including stakeholder involvement, IAEA Model Projects on Upgrading Radiation Protection Infrastructure, Quality Assurance, education and training, regulatory activities, performance evaluation, source security, and emergency preparedness. The material in this book has not been edited by the IAEA. These contributed papers will be published on a CD ROM as part of the Proceedings of the Conference, along with the invited papers and discussions. The papers are grouped by topical sessions: Stakeholder Involvement in Building and Maintaining National Radiation Safety Infrastructure (National and International); Implementation Experience with The Model Projects (Views From The Countries, Positive and Negative Experiences); Resources and Services (Systematic Approach), Quality Assurance, International Support Of Services; Sustainable Education And Training: Developing Skills (National Systems And Regional Solutions); Needs for Education And Training at The International Level (Including IAEA Programmes Assisting in Establishing Adequate Infrastructures); Authorization, Inspection and Enforcement (Effectiveness and Efficiency Of The Activities Of The Regulatory Bodies), Independence of Regulatory Authorities; Performance Evaluation; Source Security and Emergency Preparedness (Infrastructure Requirements at the International, National And User's Level)

DAE-BRNS symposium on nuclear physics: contributed papers. V. 44B

International Nuclear Information System (INIS)

Jain, Arun K.; Biswas, D.C.

2001-12-01

Nuclear Physics Symposium always got newer inputs from across the border of atomic physics, condensed matter physics, high energy physics, nuclear astrophysics etc. It has contributed for the growth and development of topics such as quark gluon plasma (QGP), Accelerator Physics, Nuclear Detectors, Accelerator Driven Systems etc. Out of many of these topics the main highlights of this proceedings were: (1) discussion on the first detailed results using the Clover Array at various heavy ion accelerators operating in the country; (2) physics with Radioactive Ion Beams (RIB) as the fast emerging areas of nuclear physics to probe the structure and reactions involving nuclei far away from the region of stability and approaching the drip lines and (3) QGP. Papers relevant to INIS are indexed separately

PLANETESIMAL AND PROTOPLANET DYNAMICS IN A TURBULENT PROTOPLANETARY DISK: IDEAL STRATIFIED DISKS

International Nuclear Information System (INIS)

Yang, Chao-Chin; Mac Low, Mordecai-Mark; Menou, Kristen

2012-01-01

Due to the gravitational influence of density fluctuations driven by magneto-rotational instability in the gas disk, planetesimals and protoplanets undergo diffusive radial migration as well as changes in other orbital properties. The magnitude of the effect on particle orbits can have important consequences for planet formation scenarios. We use the local-shearing-box approximation to simulate an ideal, isothermal, magnetized gas disk with vertical density stratification and simultaneously evolve numerous massless particles moving under the gravitational field of the gas and the host star. We measure the evolution of the particle orbital properties, including mean radius, eccentricity, inclination, and velocity dispersion, and its dependence on the disk properties and the particle initial conditions. Although the results converge with resolution for fixed box dimensions, we find the response of the particles to the gravity of the turbulent gas correlates with the horizontal box size, up to 16 disk scale heights. This correlation indicates that caution should be exercised when interpreting local-shearing-box models involving gravitational physics of magneto-rotational turbulence. Based on heuristic arguments, nevertheless, the criterion L h /R ∼ O(1), where L h is the horizontal box size and R is the distance to the host star, is proposed to possibly circumvent this conundrum. If this criterion holds, we can still conclude that magneto-rotational turbulence seems likely to be ineffective at driving either diffusive migration or collisional erosion under most circumstances.

Invited and contributed papers presented at the 22. EPS conference on controlled fusion and plasma physics

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-08-01

In this report one invited and fifteen contributed papers by researchers of the `Centre de Recherche en Physique des Plasmas`, Lausanne, to the 22. EPS Conference on Controlled Fusion and Plasma Physics are assembled. figs., tabs., refs.

International conference on the safety of radioactive waste disposal. Contributed papers

International Nuclear Information System (INIS)

2005-01-01

The objective of the Conference is to foster information exchange on the safety of radioactive waste disposal covering; the choice of appropriate waste disposal options, safety standards, safety cases for presenting safety arguments and demonstrating compliance with standards, safety assessment methodologies and their application, dealing with uncertainty, regulatory review and decision making, the derivation of limits, controls and conditions to be applied to the development and operation of disposal facilities to ensure safety and the communication of safety issues to all interested stakeholders and confidence development. The conference will consider all possible disposal options available, drawing from experience in Member States with near surface and geological disposal facilities and those at intermediate depths and giving consideration to any multilateral approach that may be adopted. Each of the contributed papers is indexed separately

International conference on the safety of radioactive waste disposal. Contributed papers

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-07-01

The objective of the Conference is to foster information exchange on the safety of radioactive waste disposal covering; the choice of appropriate waste disposal options, safety standards, safety cases for presenting safety arguments and demonstrating compliance with standards, safety assessment methodologies and their application, dealing with uncertainty, regulatory review and decision making, the derivation of limits, controls and conditions to be applied to the development and operation of disposal facilities to ensure safety and the communication of safety issues to all interested stakeholders and confidence development. The conference will consider all possible disposal options available, drawing from experience in Member States with near surface and geological disposal facilities and those at intermediate depths and giving consideration to any multilateral approach that may be adopted. Each of the contributed papers is indexed separately.

Increases to Inferred Rates of Planetesimal Accretion due to Thermohaline Mixing in Metal-accreting White Dwarfs

Science.gov (United States)

Bauer, Evan B.; Bildsten, Lars

2018-06-01

Many isolated, old white dwarfs (WDs) show surprising evidence of metals in their photospheres. Given that the timescale for gravitational sedimentation is astronomically short, this is taken as evidence for ongoing accretion, likely of tidally disrupted planetesimals. The rate of such accretion, {\\dot{M}}acc}, is important to constrain, and most modeling of this process relies on assuming an equilibrium between diffusive sedimentation and metal accretion supplied to the WD’s surface convective envelope. Building on the earlier work of Deal and collaborators, we show that high {\\dot{M}}acc} models with only diffusive sedimentation are unstable to thermohaline mixing and that models that account for the enhanced mixing from the active thermohaline instability require larger accretion rates, sometimes reaching {\\dot{M}}acc}≈ {10}13 {{g}} {{{s}}}-1 to explain observed calcium abundances. We present results from a grid of MESA models that include both diffusion and thermohaline mixing. These results demonstrate that both mechanisms are essential for understanding metal pollution across the range of polluted WDs with hydrogen atmospheres. Another consequence of active thermohaline mixing is that the observed metal abundance ratios are identical to accreted material.

After runaway: The trans-Hill stage of planetesimal growth

International Nuclear Information System (INIS)

Lithwick, Yoram

2014-01-01

When planetesimals begin to grow by coagulation, they first enter an epoch of runaway, during which the biggest bodies grow faster than all the others. The questions of how runaway ends and what comes next have not been answered satisfactorily. We show that runaway is followed by a new stage—the 'trans-Hill stage'—that commences when the bodies that dominate viscous stirring ('big bodies') become trans-Hill, i.e., when their Hill velocity matches the random speed of the small bodies they accrete. Subsequently, the small bodies' random speed grows in lockstep with the big bodies' sizes, such that the system remains in the trans-Hill state. Trans-Hill growth is crucial for determining the efficiency of growing big bodies, as well as their growth timescale and size spectrum. Trans-Hill growth has two sub-stages. In the earlier one, which occurs while the stirring bodies remain sufficiently small, the evolution is collisionless, i.e., collisional cooling among all bodies is irrelevant. The efficiency of forming big bodies in this collisionless sub-stage is very low, ∼10α << 1, where α ∼ 0.005(a/AU) –1 is the ratio between the physical size of a body and its Hill radius. Furthermore, the size spectrum is flat (equal mass per size decade, i.e., q = 4). This collisionless trans-Hill solution explains results from previous coagulation simulations for both the Kuiper Belt and the asteroid belt. The second trans-Hill sub-stage commences once the stirring bodies grow big enough (>α –1 × the size of the accreted small bodies). After that time, collisional cooling among small bodies controls the evolution. The efficiency of forming big bodies rises and the size spectrum becomes more top heavy. Trans-Hill growth can terminate in one of two ways, depending on the sizes of the small bodies. First, mutual accretion of big bodies can become significant and conglomeration proceeds until half of the total mass is converted into big bodies

International conference on lessons learned from the decommissioning of nuclear facilities and the safe termination of nuclear activities. Contributed papers

International Nuclear Information System (INIS)

2006-12-01

The International Atomic Energy Agency (IAEA), in cooperation with the European Commission (EC), Nuclear Energy Agency to the Organisation for Economic Co-operation and Development (OECD/NEA), and the World Nuclear Association (WNA), organized an International Conference on Lessons Learned from the Decommissioning of Nuclear Facilities and the Safe Termination of Nuclear Activities from 11 to 15 December 2006 in Athens, Greece. This Book of Contributed Papers contains technical papers and posters contributed by experts from operating organisations, regulatory bodies, technical support organisations, and other institutions on issues falling within the scope of the Conference. The following main topics were covered: Evolution of national and international policies and criteria for the safe and efficient decommissioning of nuclear facilities and safe termination of nuclear activities; Review of lessons learned from ongoing or completed activities associated with decommissioning; Improvement of safety and efficiency through the use of new and innovative technologies; Practical aspects in the management of material, waste and sites resulting from decommissioning, including the management of waste in the absence of repositories and waste acceptance requirements; Procedures for demonstrating compliance with clearance criteria; Experience from radiological assessments associated with decommissioning; Involvement of the local communities and the impact that decommissioning activities has on them. The presented papers and posters were reviewed and accepted following the guidelines established by the Conference Programme Committee for consideration at the Conference. The material compiled in this Book of Contributed Papers has not undergone rigorous editing by the editorial staff of the IAEA. However, certain modifications were made: a unified format was adopted for all papers; and minor corrections were made in the text where required. Each paper and poster has been indexed

International conference on lessons learned from the decommissioning of nuclear facilities and the safe termination of nuclear activities. Contributed papers

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-12-15

The International Atomic Energy Agency (IAEA), in cooperation with the European Commission (EC), Nuclear Energy Agency to the Organisation for Economic Co-operation and Development (OECD/NEA), and the World Nuclear Association (WNA), organized an International Conference on Lessons Learned from the Decommissioning of Nuclear Facilities and the Safe Termination of Nuclear Activities from 11 to 15 December 2006 in Athens, Greece. This Book of Contributed Papers contains technical papers and posters contributed by experts from operating organisations, regulatory bodies, technical support organisations, and other institutions on issues falling within the scope of the Conference. The following main topics were covered: Evolution of national and international policies and criteria for the safe and efficient decommissioning of nuclear facilities and safe termination of nuclear activities; Review of lessons learned from ongoing or completed activities associated with decommissioning; Improvement of safety and efficiency through the use of new and innovative technologies; Practical aspects in the management of material, waste and sites resulting from decommissioning, including the management of waste in the absence of repositories and waste acceptance requirements; Procedures for demonstrating compliance with clearance criteria; Experience from radiological assessments associated with decommissioning; Involvement of the local communities and the impact that decommissioning activities has on them. The presented papers and posters were reviewed and accepted following the guidelines established by the Conference Programme Committee for consideration at the Conference. The material compiled in this Book of Contributed Papers has not undergone rigorous editing by the editorial staff of the IAEA. However, certain modifications were made: a unified format was adopted for all papers; and minor corrections were made in the text where required. Each paper and poster has been indexed

Particle Size Distributions in Chondritic Meteorites: Evidence for Pre-Planetesimal Histories

Science.gov (United States)

Simon, J. I.; Cuzzi, J. N.; McCain, K. A.; Cato, M. J.; Christoffersen, P. A.; Fisher, K. R.; Srinivasan, P.; Tait, A. W.; Olson, D. M.; Scargle, J. D.

2018-01-01

Magnesium-rich silicate chondrules and calcium-, aluminum-rich refractory inclusions (CAIs) are fundamental components of primitive chondritic meteorites. It has been suggested that concentration of these early-formed particles by nebular sorting processes may lead to accretion of planetesimals, the planetary bodies that represent the building blocks of the terrestrial planets. In this case, the size distributions of the particles may constrain the accretion process. Here we present new particle size distribution data for Northwest Africa 5717, a primitive ordinary chondrite (ungrouped 3.05) and the well-known carbonaceous chondrite Allende (CV3). Instead of the relatively narrow size distributions obtained in previous studies (Ebel et al., 2016; Friedrich et al., 2015; Paque and Cuzzi, 1997, and references therein), we observed broad size distributions for all particle types in both meteorites. Detailed microscopic image analysis of Allende shows differences in the size distributions of chondrule subtypes, but collectively these subpopulations comprise a composite "chondrule" size distribution that is similar to the broad size distribution found for CAIs. Also, we find accretionary 'dust' rims on only a subset (approximately 15-20 percent) of the chondrules contained in Allende, which indicates that subpopulations of chondrules experienced distinct histories prior to planetary accretion. For the rimmed subset, we find positive correlation between rim thickness and chondrule size. The remarkable similarity between the size distributions of various subgroups of particles, both with and without fine grained rims, implies a common size sorting process. Chondrite classification schemes, astrophysical disk models that predict a narrow chondrule size population and/or a common localized formation event, and conventional particle analysis methods must all be critically reevaluated. We support the idea that distinct "lithologies" in NWA 5717 are nebular aggregates of

Safety of radiation sources and security of radioactive materials. Contributed papers

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-09-01

The International Atomic Energy Agency (IAEA) in co-operation with the European Commission (EC), International Criminal Police Organization (INTERPOL) and the World Customs Organization (WCO) organized an International Conference on the Safety of Radiation Sources and the Security of Radioactive Materials, in Dijon, France, from 14 to 18 September 1998. The Government of France hosted this Conference through the Commissariat a l`energie atomique, Direction des applications militaires (CEA/DAM). This TECDOC contains the contributed papers dealing with the topics of this Conference which were accepted by the Conference Programme Committee for presentation. The papers written in one of the two working languages of the Conference, English or French are presented here each by a separate abstract. Ten technical sessions covered the following subjects: the regulatory control of radiation sources, including systems for notification, authorization and inspection; safety assessment techniques applied to radiation sources and design and technological measures including defense in depth and good engineering practice; managerial measures, including safety culture, human factors, quality assurance, qualified experts, training and education; learning from operational experience; international co-operation, including reporting systems and databases; verification of compliance, monitoring of compliance and assessment of the effectiveness of national programmes for the safety of sources; measures to prevent breaches in the security of radioactive materials, experience with criminal acts involving radioactive materials; detection and identification technologies for illicitly trafficked radioactive materials; response to detected cases and seized radioactive materials, strengthening of the awareness, training and exchange of information. The IAEA plans to issue the proceedings of this Conference containing the invited presentations, rapporteurs and Chairpersons overviews and summaries

Safety of radiation sources and security of radioactive materials. Contributed papers

International Nuclear Information System (INIS)

1998-09-01

The International Atomic Energy Agency (IAEA) in co-operation with the European Commission (EC), International Criminal Police Organization (INTERPOL) and the World Customs Organization (WCO) organized an International Conference on the Safety of Radiation Sources and the Security of Radioactive Materials, in Dijon, France, from 14 to 18 September 1998. The Government of France hosted this Conference through the Commissariat a l'energie atomique, Direction des applications militaires (CEA/DAM). This TECDOC contains the contributed papers dealing with the topics of this Conference which were accepted by the Conference Programme Committee for presentation. The papers written in one of the two working languages of the Conference, English or French are presented here each by a separate abstract. Ten technical sessions covered the following subjects: the regulatory control of radiation sources, including systems for notification, authorization and inspection; safety assessment techniques applied to radiation sources and design and technological measures including defense in depth and good engineering practice; managerial measures, including safety culture, human factors, quality assurance, qualified experts, training and education; learning from operational experience; international co-operation, including reporting systems and databases; verification of compliance, monitoring of compliance and assessment of the effectiveness of national programmes for the safety of sources; measures to prevent breaches in the security of radioactive materials, experience with criminal acts involving radioactive materials; detection and identification technologies for illicitly trafficked radioactive materials; response to detected cases and seized radioactive materials, strengthening of the awareness, training and exchange of information. The IAEA plans to issue the proceedings of this Conference containing the invited presentations, rapporteurs and Chairpersons overviews and summaries

Accretion timescales and style of asteroidal differentiation in an 26Al-poor protoplanetary disk

DEFF Research Database (Denmark)

Larsen, Kirsten Kolbjørn; Schiller, Martin; Bizzarro, Martin

2016-01-01

, intrinsically linked to the thermal evolution of early-formed planetesimals. In this paper, we explore the timing and style of asteroidal differentiation by combining high-precision Mg isotope measurements of meteorites with thermal evolution models for planetesimals. In detail, we report Mg isotope data...... the source rock. We propose that their parent planetesimals started forming within ~250,000years of solar system formation from a hot (>~500K) inner protoplanetary disk region characterized by a reduced initial (26Al/27Al)0 abundance (~1-2×10-5) relative to the (26Al/27Al)0 value in CAIs of 5...

High velocity collisions between large dust aggregates at the limit for growing planetesimals

Science.gov (United States)

Wurm, G.; Teiser, J.; Paraskov, G.

2007-08-01

Planetesimals are km-size bodies supposed to be formed in protoplanetary disks as planetary precursors [1]. The most widely considered mechanism for their formation is based on mutual collisions of smaller bodies, a process which starts with the aggregation of (sub)-micron size dust particles. In the absence of events that lithify the growing dust aggregates, only the surface forces between dust particles provide adhesion and internal strength of the objects. It has been assumed that this might be a disadvantage as dust aggregates are readily destroyed by rather weak collisions. In fact, experimental research on dust aggregation showed that for collisions in the m/s range (sub)-mm size dust aggregates impacting a larger body do show a transition from sticking to rebound and/or fragmentation in collisions and no growth occurs at the large velocities [2, 3]. This seemed to be incompatible with typical collision velocities of small dust aggregates with m-size bodies which are expected to be on the order 50 m/s in protoplanetary disks [4]. We recently found that the experimental results cannot be scaled from m/s to tens of m/s collisions. In contrast to the assumptions and somewhat counterintuitive, it is the fragility of dust aggregates that allows growth at higher collision velocities. In impact experiments Wurm et al. [5] showed that between 13 m/s and 25 m/s a larger compact (target) body consisting of micron-size SiO2 dust particles accreted 50 % of the mass of a 1 cm dust projectile consisting of the same dust. For slower impacts the projectile only rebounded or fragmented slightly.

Review of research institute library activity through the contributed papers. The case of the Japan Atomic Energy Research Institute Library

International Nuclear Information System (INIS)

Ikeda, Kiyoshi; Habara, Tadashi; Ishikawa, Masashi; Itabashi, Keizo; Yonezawa, Minoru

2007-03-01

The Japan Atomic Energy Research Institute (JAERI) Library had contributed 312 papers through the library activities in half-century. We made the bibliography of these papers as well as categorized them into general', 'library functions', 'management and promotion of research results' and 'international exchange of information' and explained them under the four categories. A subject index, an author index of these papers and chronology of JAERI library activities were also compiled for reference. (author)

THE LINK BETWEEN PLANETARY SYSTEMS, DUSTY WHITE DWARFS, AND METAL-POLLUTED WHITE DWARFS

International Nuclear Information System (INIS)

Debes, John H.; Walsh, Kevin J.; Stark, Christopher

2012-01-01

It has long been suspected that metal-polluted white dwarfs (types DAZ, DBZ, and DZ) and white dwarfs with dusty disks possess planetary systems, but a specific physical mechanism by which planetesimals are perturbed close to a white dwarf has not yet been fully posited. In this paper, we demonstrate that mass loss from a central star during post-main-sequence evolution can sweep planetesimals into interior mean motion resonances with a single giant planet. These planetesimals are slowly removed through chaotic excursions of eccentricity that in time create radial orbits capable of tidally disrupting the planetesimal. Numerical N-body simulations of the solar system show that a sufficient number of planetesimals are perturbed to explain white dwarfs with both dust and metal pollution, provided other white dwarfs have more massive relic asteroid belts. Our scenario requires only one Jupiter-sized planet and a sufficient number of asteroids near its 2:1 interior mean motion resonance. Finally, we show that once a planetesimal is perturbed into a tidal crossing orbit, it will become disrupted after the first pass of the white dwarf, where a highly eccentric stream of debris forms the main reservoir for dust-producing collisions. These simulations, in concert with observations of white dwarfs, place interesting limits on the frequency of planetary systems around main-sequence stars, the frequency of planetesimal belts, and the probability that dust may obscure future terrestrial planet finding missions.

Invited and contributed papers presented by the theory group at the joint Varenna-Lausanne international workshop 'theory of fusion plasmas'

International Nuclear Information System (INIS)

1996-09-01

In this report eight invited and contributed papers of the theory group are included which were presented at joint Varenna-Lausanne international workshop on 'theory of fusion plasmas'. (author) figs., tabs., refs

International conference on the protection of the environment from the effects of ionizing radiation. Contributed papers

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-09-01

An International Conference on the Protection of the Environment from the Effects of Ionizing Radiation, organized by the International Atomic Energy Agency (IAEA) in co-operation with the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), the European Commission (EC) and the International Union of Radioecology (IUR), will be held in Stockholm, Sweden, from 6-10 October 2003. This Conference will be hosted by the Government of Sweden through the Swedish Radiation Protection Authority (SSI). This publication contains contributed papers submitted on issues within the scope of the conference, which were accepted following a review by the Conference Programme Committee. The primary objective of this Conference is to foster information exchange, with the aim of promoting the development of a coherent international policy on the protection of the environment from effects attributable to ionizing radiation. This Conference is one in a series of meetings organized by, or held in co-operation with, the IAEA on this subject. It will include a review of recent developments in this area, and consideration of their implications for future work at national and international levels. The topics on which contributed papers were requested are as follows: Existing environmental protection approaches; Development of an international assessment framework; The scientific basis for environmental radiation assessment; Development of management approaches.

Water and the Interior Structure of Terrestrial Planets and Icy Bodies

Science.gov (United States)

Monteux, J.; Golabek, G. J.; Rubie, D. C.; Tobie, G.; Young, E. D.

2018-02-01

Water content and the internal evolution of terrestrial planets and icy bodies are closely linked. The distribution of water in planetary systems is controlled by the temperature structure in the protoplanetary disk and dynamics and migration of planetesimals and planetary embryos. This results in the formation of planetesimals and planetary embryos with a great variety of compositions, water contents and degrees of oxidation. The internal evolution and especially the formation time of planetesimals relative to the timescale of radiogenic heating by short-lived 26Al decay may govern the amount of hydrous silicates and leftover rock-ice mixtures available in the late stages of their evolution. In turn, water content may affect the early internal evolution of the planetesimals and in particular metal-silicate separation processes. Moreover, water content may contribute to an increase of oxygen fugacity and thus affect the concentrations of siderophile elements within the silicate reservoirs of Solar System objects. Finally, the water content strongly influences the differentiation rate of the icy moons, controls their internal evolution and governs the alteration processes occurring in their deep interiors.

Heterogeneous Delivery of Silicate and Metal to the Earth via Large Planetesimals

Science.gov (United States)

Marchi, S.; Canup, R. M.; Walker, R. J.

2017-12-01

Earth's mantle abundances of at least some highly siderophile elements, (HSE; Re, Os, Ir, Ru, Pt, Rh, Pd, and Au), are much higher than would result from metal-silicate equilibration during terrestrial core formation, and can be better explained as a result of late accretion of a minimum of 0.5% Earth's masses after core formation was complete. Traditional models assume that HSEs delivered by late projectiles completely mixed and chemically equilibrated with the Earth's mantle. This appears likely for undifferentiated, well-mixed projectiles, or for relatively small, differentiated projectiles. However several arguments suggest that late projectiles may have been large (> 1500 km in diameter) and differentiated, and in this case, portions of the projectile's core may merge with the Earth's core, rather than being mixed into the Earth's mantle. We investigate projectile mixing with a suite of SPH simulations of differentiated planetesimal colliding with the Earth. A range of outcomes emerge from our simulations suggesting that for large impactors (>1500 km), the delivery of HSE to the Earth's mantle may be disproportionate with the overall delivery of mass. For impacts with impact angles 60°, most of the impactor core escapes for moderate impact speeds. An implication is that the late accreted mass inferred from terrestrial HSE abundances may be a substantial underestimate, by a factor 2-5. In addition, partial mixing of projectiles result in an enrichment in mantle vs core material delivered to the bulk silicate Earth, implying substantial compositional variations in the accreted mass. Such variations could produce initially localized domains in Earth's mantle with distinct, mass independent isotopic signatures, given the isotopic variability resulting from nucleosynthetic heterogeneities among genetically diverse meteorites. In general we find that larger, low angle collisions would be more likely to produce initial mantle domains of anomalous composition

International symposium on high pressure low temperature plasma chemistry. Contributed papers

International Nuclear Information System (INIS)

1998-01-01

The proceedings contain the texts of 77 contributions, of which 31 contributions fall within the scope of the INIS database. The latter deal with various aspects of plasma behavior in pulsed electric discharges of various types, with the spectroscopic and probe diagnostics of a discharge plasma, and with the computer simulation of ionization and breakdown processes in the glow, corona, and arc discharges at atmospheric pressure. (J.U.)

International symposium on high pressure low temperature plasma chemistry. Contributed papers

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-06-01

The proceedings contain the texts of 77 contributions, of which 31 contributions fall within the scope of the INIS database. The latter deal with various aspects of plasma behavior in pulsed electric discharges of various types, with the spectroscopic and probe diagnostics of a discharge plasma, and with the computer simulation of ionization and breakdown processes in the glow, corona, and arc discharges at atmospheric pressure. (J.U.).

Book of abstracts. Invited and contributed papers

International Nuclear Information System (INIS)

1995-01-01

The book is a collection of abstracts submitted to the International Nuclear Physics Conference held in August 21-26 1995 in Beijing, China. The conference is organized by China Institute of Atomic Energy. The main topics of the conference are: relativistic nuclear collisions, mesons and baryons in nuclei, hadron structure and quarks in nuclei, formation and properties of hot nuclei, nuclear reactions at low and intermediate energies, nuclear structure, radioactive nuclear beams, nuclear astrophysics, fundamental interaction and symmetries, applied nuclear physics. This second part contains papers about nuclear reactions at low and intermediate energies, nuclear structure, radioactive nuclear beams, nuclear astrophysics, fundamental interaction and symmetries, applied nuclear physics, and the author index

The Acapulco Parent Planetesimal: An Early Collisional History in the Solar System

Science.gov (United States)

Marti, K.; Kim, Y.

2007-05-01

The Acapulco, Mexico, meteorite was recovered in 1976 from a crater of approx. 30 cm diameter. An old crystallization age of 4.60 (error 0.03) Ga (Prinzhofer et al., 1992) establishes that its parent object is one of the oldest known planetesimals in the solar system, although not in a pristine form. Other dating systems indicated somewhat younger ages and isotopic variabilities in several elements documented a complex early history. The younger ages date the closure times in secondary minerals. The initial parent object was in a partially molten state when isotopically distinct foreign matter invaded the chondritic parent and some of the isotopic signatures survived. Nitrogen in the primitive achondrite Acapulco was found to have distinct isotopic signatures for the metal and silicate phases and also in different morphologies of graphites (El Goresy, 1995, 2005). The delayed collisional event probably disrupted the parent object, as Acapulco cooled very rapidly. Nitrogen in the injected metal and graphite did not isotopically exchange with the host silicates. We observed nitrogen isotopic signatures of several separated mineral phases which cover a range of delta 15N values from -150 permil to +13 permil. The lightest nitrogen signatures observed in metal separates are comparable to those in some morphologies of Acapulco graphites. The heavy N signatures observed in several silicate minerals are consistent with each other, while nitrogen in chromite is distinctly light (delta 15N of -80 permil), intermediate between those of metal and silicates. The incipient rapid cooling history is well documented down to approx. 120° C, as recorded by U/Th-4He ages in phosphates (Min et al., 2003). The history of the Acapulco parent object was uneventful after its early evolution in an environment where no perturbation by collisions occurred, until the meteorite's recent (6.0 Ma ago) injection into an earth-crossing orbit. References: El Goresy, A., Zinner, E., and Marti, K

Symposium on quantum electronics. Extended abstracts of contributed papers

Energy Technology Data Exchange (ETDEWEB)

1981-02-01

Extended abstracts are provided for papers presented in these subject areas: lasers; quantum optics; nonlinear optics; laser photochemistry; laser spectroscopy; laser scattering; laser produced plasma; and laser applications. (GHT)

Multistage Core Formation in Planetesimals Revealed by Numerical Modeling and Hf-W Chronometry of Iron Meteorites

Science.gov (United States)

Neumann, W.; Kruijer, T. S.; Breuer, D.; Kleine, T.

2018-02-01

Iron meteorites provide some of the most direct insights into the processes and timescales of core formation in planetesimals. Of these, group IVB irons stand out by having one of the youngest 182Hf-182W model ages for metal segregation (2.9 ± 0.6 Ma after solar system formation), as well as the lowest bulk sulfur content and hence highest liquidus temperature. Here, using a new model for the internal evolution of the IVB parent body, we show that a single stage of metal-silicate separation cannot account for the complete melting of pure Fe metal at the relatively late time given by the Hf-W model age. Instead, a complex metal-silicate separation scenario is required that includes migration of partial silicate melts, formation of a shallow magma ocean, and core formation in two distinct stages of metal segregation. In the first stage, a protocore formed at ≈1.5 Ma via settling of metal particles in a mantle magma ocean, followed by metal segregation from a shallow magma ocean at ≈5.4 Ma. As these stages of metal segregation occurred at different times, the two metal fractions had different 182W compositions. Consequently, the final 182W composition of the IVB core does not correspond to a single differentiation event, but represents the average composition of early- and late-segregated core fractions. Our best fit model indicates an ≈100 km radius for the IVB parent body and provides an accretion age of ≈0.1-0.5 Ma after solar system formation. The computed solidification time is, furthermore, consistent with the Re-Os age for crystallization of the IVB core.

A Review Paper: Contributions from the Gravity and the Kelvin Modes for the Vertical Motion Response.

Directory of Open Access Journals (Sweden)

Julio Buchmann

2009-10-01

Full Text Available In earlier papers of a series of real data integrations of the National Center for Atmospheric Research (NCAR Community Climate Model (CCM with tropical heat anomalies display regions of pronounced subsidence and drying located several thousand kilometers westward poleward of the heating for cases of tropical Atlantic heating and tropical east Pacific heating. This highly predictable sinking response is established within the first five days of these integrations. The normal-modes of a set of nonlinear primitive equations for an atmosphere: Adiabatic, hydrostatic, incompressible, dry, without friction and viscosity are linearized about a basic state at rest and used to partition model response into gravity-inertia and Rossby modes. The emphasis of this review is given upon the contributions of the gravity and Kelvin modes for the vertical motion response.

Radioactivity in fine papers

International Nuclear Information System (INIS)

Taylor, H.W.; Singh, B.

1993-01-01

The radioactivity of fine papers has been studied through γ-ray spectroscopy with an intrinsic Ge detector. Samples of paper from European and North American sources were found to contain very different amounts of 226 Ra and 232 Th. The processes which introduce radionuclides into paper are discussed. The radioactivity from fine papers makes only a small contribution to an individual's annual radiation dose; nevertheless it is easily detectable and perhaps, avoidable. (Author)

Planet X as the source of the periodic and steady-state flux of short period comets

International Nuclear Information System (INIS)

Matese, J.J.; Whitmire, D.P.

1986-01-01

The cratering and fossil records suggest that impacts on the earth have been modulated with a period of roughly 30 Myr. In the Planet X model, this modulation is the result of the interaction of Planet X with a primordial disk of planetesimals lying beyond the orbit of Neptune. In this paper, observational and theoretical evidence supporting the existence of Planet X and the planetesimal disk is briefly reviewed, and the constraints on the orbit parameters of Planet X and the disk parameters which must be satisfied to ensure consistency with observational limits are discussed

Contribution of Heavy Water Board in nuclear fuel cycle technologies. Contributed Paper IT-03

International Nuclear Information System (INIS)

Mohanty, P.R.

2014-01-01

The three stage Indian nuclear power programme envisages use of closed nuclear fuel cycle and thorium utilization as its mainstay for long term energy security on sustainable basis. India is committed to realize this objective through the development and deployment of frontier technologies pertaining to all aspects of a closed nuclear fuel cycle. Comprehensive indigenous capabilities have been developed in all aspects of nuclear power and associated fuel cycles. Heavy Water Board (HWB), with its abiding objective of fulfilling demand of heavy water for India's flourishing nuclear power program, is one of the frontrunner in Nuclear Fuel Cycle Technology. HWB is now engaged in wide spectrum of activities in various facets of fuel cycle covering all the three stages of Indian Nuclear Power Programme. HWB is contributing to Nuclear Fuel Cycle through large scale production and sustained supply of key input materials including heavy water, solvents for nuclear hydrometallurgy, 10 B enriched boron etc

Erwin Schroedinger: Collected papers V. 1. Contributions to statistical mechanics

International Nuclear Information System (INIS)

Schroedinger, E.

1984-01-01

38 publications reprinted in this volume show that the interest for statistical problems accompanied Schroedinger during his entire scientific career. Already in his second paper he worked on the magnetism of solid states. The classical considerations come close to the heart of diamagnetism and also to the origin of paramagnetism. In classical investigations of the specific heat Schroedinger helped through abstract theory but also by analysing a gigantic amount of experimental material. In 1926 he and F. Kohlrausch actually played the 'Urngame of Ehrenfest' as a model of the H-curve and published the results. Inclination towards experimenting, sequences of measurements and statistical evaluation of experimental data led to papers on the foundation of the theory of probability, where he tries to put the subjective probability concept on into a systematic framework. Two earlier papers on dynamics of the elastic chain remained particularly valuable. By solving the initial value problem with Bessel-functions this many-body-problem is led to an explicit discussion. These studies are likely to be the roots of another keynote in Schroedinger's thinking, namely, the irreversibility. 1945 a statistical theory of chain-reactions was published under the inconspicuous title of 'Probability Problems in Nuclear Chemistry'. In his last work Schroedinger turns off in a wrong direction: it is that energy should only be a statistical concept and should not be conserved in elementary processes, but somehow only in the mean. These short remarks only illuminate the diversity of the material in this volume, but testify Schroedinger's deep understanding in this field. (W.K.)

High Resolution N-Body Simulations of Terrestrial Planet Growth

Science.gov (United States)

Clark Wallace, Spencer; Quinn, Thomas R.

2018-04-01

We investigate planetesimal accretion with a direct N-body simulation of an annulus at 1 AU around a 1 M_sun star. The planetesimal ring, which initially contains N = 106 bodies is evolved through the runaway growth stage into the phase of oligarchic growth. We find that the mass distribution of planetesimals develops a bump around 1022 g shortly after the oligarchs form. This feature is absent in previous lower resolution studies. We find that this bump marks a boundary between growth modes. Below the bump mass, planetesimals are packed tightly enough together to populate first order mean motion resonances with the oligarchs. These resonances act to heat the tightly packed, low mass planetesimals, inhibiting their growth. We examine the eccentricity evolution of a dynamically hot planetary embryo embedded in an annulus of planetesimals and find that dynamical friction acts more strongly on the embryo when the planetesimals are finely resolved. This effect disappears when the annulus is made narrow enough to exclude most of the mean motion resonances. Additionally, we find that the 1022 g bump is significantly less prominent when we follow planetesimal growth with a skinny annulus.This feature, which is reminiscent of the power law break seen in the size distribution of asteroid belt objects may be an important clue for constraining the initial size of planetesimals in planet formation models.

ANCLI: white papers. Major contribution to public debate in France on nuclear waste policy

International Nuclear Information System (INIS)

Sene, M.

2006-01-01

Local Information Commissions (CLI) were first set up in autumn 1981 following the 'Mauroy circular' sent out by then Prime Minister, Pierre Mauroy. To date (2006), 30 CLIs have been set up. The status and funding for these CLIs have lacked consistency, subject to the good will of the political authorities. However, since being set up, the value of these commissions has become more and more apparent: the French now have somewhere where they can express their opinions. It is for this reason that, for almost ten years, the CLIs have called for a legislative framework in recognition of their existence: this has now been achieved, under the provisions of the Nuclear Transparency and Safety Act passed on 13 June 2006. It is a shame, however, that this Act does not explicitly recognize the existence of the National Association of Local Information Commissions (ANCLI), set up in 2000 and grouping together 20 CLIs (2006). When two public debates were announced, one on waste management and the other on the European Pressurized Reactor (EPR), ANCLI set up a working group to investigate the subject of 'Local Governance of nuclear sites' and which published its findings in May 2005. Thanks to the extremely positive reaction this Paper received, both on the part of the CLIs and within political circles, ANCLI initiated a study focused more directly on nuclear waste management. This working group's research has resulted in the publication of the 'Livre Blanc de l'ANCLI - Matieres et dechets radioactifs/territoires' - ANCLI's White Paper on radioactive materials and waste and local communities (June 2006).This Paper was published after the Act of 28 June 2006 relative to 'National policy on sustainable management of radioactive materials and waste' was passed. Members of the French parliament were informed of the key ideas it contains. This 'White Book' is a contribution to public debate on nuclear waste and on EPR. In a first approach, the ANCLI is not considered as a partner

Rabi N. Bhattacharya selected papers

CERN Document Server

Waymire, Edward

2016-01-01

This volume presents some of the most influential papers published by Rabi N. Bhattacharya, along with commentaries from international experts, demonstrating his knowledge, insight, and influence in the field of probability and its applications. For more than three decades, Bhattacharya has made significant contributions in areas ranging from theoretical statistics via analytical probability theory, Markov processes, and random dynamics to applied topics in statistics, economics, and geophysics. Selected reprints of Bhattacharya’s papers are divided into three sections: Modes of Approximation, Large Times for Markov Processes, and Stochastic Foundations in Applied Sciences. The accompanying articles by the contributing authors not only help to position his work in the context of other achievements, but also provide a unique assessment of the state of their individual fields, both historically and for the next generation of researchers. Rabi N. Bhattacharya: Selected Papers will be a valuable resource for yo...

Nuclear fuel cycle and reactor strategies: Adjusting to new realities. Contributed papers

International Nuclear Information System (INIS)

1997-12-01

The International Symposium on Nuclear Fuel Cycle and Reactor Strategies: Adjusting to New Realities was held from 3 to 6 June 1997 in Vienna, Austria. It was organized by the International Atomic Energy Agency (IAEA) in co-operation with the European Commission, the Nuclear Energy Agency of the OECD (OECD/NEA) and the Uranium Institute (UI). More than 300 participants from more than 40 countries and 5 organizations took part. The reason for organizing the symposium was to face the new realities in the nuclear fuel cycle and to come to conclusions on how these new realities should be addressed. In the light of these objectives, international working groups prepared key issue papers on six topics that were selected as the central themes for consideration at the symposium. An International Steering Group composed of the representatives of 12 countries and three international organizations co-ordinated the work of the six working groups. Each of the six working groups wrote a key issue paper. These key issue papers are published as a separate publication. During the symposium, addresses and papers presented by leading experts and policy makers provided additional information in these fields. The key issues were explored further in discussions by the participants and a panel of experts, which helped to highlight the main problems to be addressed in designing the policies for the nuclear fuel cycle in the next 50 years. Special emphasis was placed on the problem of disposition of separated plutonium of civil origin and of plutonium originating from the dismantlement of nuclear weapons. This TECDOC contains all the papers presented, together with a summary of the symposium and a list of participants

Nuclear fuel cycle and reactor strategies: Adjusting to new realities. Contributed papers

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-12-01

The International Symposium on Nuclear Fuel Cycle and Reactor Strategies: Adjusting to New Realities was held from 3 to 6 June 1997 in Vienna, Austria. It was organized by the International Atomic Energy Agency (IAEA) in co-operation with the European Commission, the Nuclear Energy Agency of the OECD (OECD/NEA) and the Uranium Institute (UI). More than 300 participants from more than 40 countries and 5 organizations took part. The reason for organizing the symposium was to face the new realities in the nuclear fuel cycle and to come to conclusions on how these new realities should be addressed. In the light of these objectives, international working groups prepared key issue papers on six topics that were selected as the central themes for consideration at the symposium. An International Steering Group composed of the representatives of 12 countries and three international organizations co-ordinated the work of the six working groups. Each of the six working groups wrote a key issue paper. These key issue papers are published as a separate publication. During the symposium, addresses and papers presented by leading experts and policy makers provided additional information in these fields. The key issues were explored further in discussions by the participants and a panel of experts, which helped to highlight the main problems to be addressed in designing the policies for the nuclear fuel cycle in the next 50 years. Special emphasis was placed on the problem of disposition of separated plutonium of civil origin and of plutonium originating from the dismantlement of nuclear weapons. This TECDOC contains all the papers presented, together with a summary of the symposium and a list of participants. Refs, figs, tabs.

Chemistry in an evolving protoplanetary disk: Effects on terrestrial planet composition

International Nuclear Information System (INIS)

Moriarty, John; Fischer, Debra; Madhusudhan, Nikku

2014-01-01

The composition of planets is largely determined by the chemical and dynamical evolution of the disk during planetesimal formation and growth. To predict the diversity of exoplanet compositions, previous works modeled planetesimal composition as the equilibrium chemical composition of a protoplanetary disk at a single time. However, planetesimals form over an extended period of time, during which elements sequentially condense out of the gas as the disk cools and are accreted onto planetesimals. To account for the evolution of the disk during planetesimal formation, we couple models of disk chemistry and dynamics with a prescription for planetesimal formation. We then follow the growth of these planetesimals into terrestrial planets with N-body simulations of late-stage planet formation to evaluate the effect of sequential condensation on the bulk composition of planets. We find that our model produces results similar to those of earlier models for disks with C/O ratios close to the solar value (0.54). However, in disks with C/O ratios greater than 0.8, carbon-rich planetesimals form throughout a much larger radial range of the disk. Furthermore, our model produces carbon-rich planetesimals in disks with C/O ratios as low as ∼0.65, which is not possible in the static equilibrium chemistry case. These results suggest that (1) there may be a large population of short-period carbon-rich planets around moderately carbon-enhanced stars (0.65 < C/O < 0.8) and (2) carbon-rich planets can form throughout the terrestrial planet region around carbon-rich stars (C/O > 0.8).

Topical issues in nuclear, radiation and radioactive waste safety. Contributed papers

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-08-01

The IAEA International Conference on Topical Issues in Nuclear, Radiation and Radioactive Waste Safety was held in Vienna, Austria, 30 August - 4 September 1998 with the objective to foster the exchange of information on topical issues in nuclear, radiation and radioactive waste safety, with the aim of consolidating an international consensus on: the present status of these issues; priorities for future work; and needs for strengthening international co-operation, including recommendations for the IAEA`s future activities. The document includes 43 papers presented at the Conference dealing with the following topical issues: Safety Management; Backfitting, Upgrading and Modernization of NPPs; Regulatory Strategies; Occupational Radiation Protection: Trends and Developments; Situations of Chronic Exposure to Residual Radioactive Materials: Decommissioning and Rehabilitation and Reclamation of Land; Radiation Safety in the Far Future: The Issue of Long Term Waste Disposal. A separate abstract and indexing were provided for each paper. Refs, figs, tabs

Topical issues in nuclear, radiation and radioactive waste safety. Contributed papers

International Nuclear Information System (INIS)

1998-08-01

The IAEA International Conference on Topical Issues in Nuclear, Radiation and Radioactive Waste Safety was held in Vienna, Austria, 30 August - 4 September 1998 with the objective to foster the exchange of information on topical issues in nuclear, radiation and radioactive waste safety, with the aim of consolidating an international consensus on: the present status of these issues; priorities for future work; and needs for strengthening international co-operation, including recommendations for the IAEA's future activities. The document includes 43 papers presented at the Conference dealing with the following topical issues: Safety Management; Backfitting, Upgrading and Modernization of NPPs; Regulatory Strategies; Occupational Radiation Protection: Trends and Developments; Situations of Chronic Exposure to Residual Radioactive Materials: Decommissioning and Rehabilitation and Reclamation of Land; Radiation Safety in the Far Future: The Issue of Long Term Waste Disposal. A separate abstract and indexing were provided for each paper

Topical papers on heavy water, fuel fabrication and reactors

International Nuclear Information System (INIS)

1978-01-01

A total of four papers is presented. The first contribution of the Federal Republic of Germany reviews the market situation for reactors and the relations between reactor producers and buyers as reflected in sales agreements. The second West German contribution gives a world-wide survey of fuel element production as well as of fuel and fuel element demand up to the year 2000. The Canadian paper discusses the future prospects of heavy-water production, while the Ecuador contribution deals with small and medium-sized nuclear power plants

The intellectual contribution of laboratory medicine professionals to research papers on laboratory medicine topics published in high-impact general medicine journals.

Science.gov (United States)

Escobar, Pedro Medina; Nydegger, Urs; Risch, Martin; Risch, Lorenz

2012-03-01

An author is generally regarded as an individual "who has made substantial intellectual academic contributions to a published study". However, the extent of the contribution that laboratory medicine professionals have made as authors of research papers in high-impact medical journals remains unclear. From 1 January 2004 to 31 March 2009, 4837 original research articles appeared in the: New England Journal of Medicine, Lancet, Annals of Internal Medicine, JAMA and BMJ. Using authorship as an indicator of intellectual contribution, we analyzed articles that included laboratory medicine parameters in their titles in an observational cross-sectional study. We also extracted data regarding radiological topics that were published during the same time within the same journals. Out of 481 articles concerning laboratory medicine topics, 380 provided information on the affiliations of the authors. At least one author from an institution within the field of laboratory medicine was listed in 212 articles (55.8%). Out of 3943 co-authors, only 756 (19.2%) were affiliated with laboratory medicine institutions. Authors from laboratory medicine institutions were listed as the first, last or corresponding authors in 99 articles (26.1%). The comparative proportions for author affiliation from 55 radiology articles were significantly higher, as 72.7% (p=0.026) of articles and 24.8% (p=0.001) of authors indicated an affiliation with a radiology institution. Radiology professionals from 72.7% of the articles were listed as either the first, last or corresponding authors (pgeneral medicine journals.

Radiological protection of patients in diagnostic and interventional radiology, nuclear medicine and radiotherapy. Contributed papers

International Nuclear Information System (INIS)

2001-01-01

An International Conference on the Radiological Protection of Patients in Diagnostic and Interventional Radiology, Nuclear Medicine and Radiotherapy organized by the International Atomic Energy Agency and co-sponsored by the European Commission, the Pan American Health Organization and the World Health Organization was held in Malaga, Spain, from 26 to 30 March 2001. The Government of Spain hosted this Conference through the Ministerio de Sanidad y Consumo, the Consejo de Seguridad Nuclear, the Junta de Andalucia, the Universidad de Malaga and the Grupo de Investigacion en Proteccion Radiologica de la Universidad de Malaga (PRUMA). The Conference was organized in co-operation with the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), the International Commission on Radiological Protection (ICRP) and the following professional societies: International Organization of Medical Physicists (IOMP), International Radiation Protection Association (IRPA), International Society of Radiation Oncology (ISRO), International Society of Radiology (ISR), International Society of Radiographers and Radiological Technologists (ISRRT) and World Federation of Nuclear Medicine and Biology (WFNMB). This publication contains contributed papers submitted to the Conference Programme Committee. The papers are in one of the two working languages of this Conference, English and Spanish. The topics covered by the Conference are as follows: Radiological protection of patients in general diagnostic radiology (radiography), Radiological protection of patients in general diagnostic radiology (fluoroscopy), Radiological protection issues in specific uses of diagnostic radiology, such as mammography and computed tomography (with special consideration of the impact of digital techniques), Radiological protection in interventional radiology, including fluoroscopy not carried out by radiologists, Radiological protection of patients in nuclear medicine, Developing and

Radiological protection of patients in diagnostic and interventional radiology, nuclear medicine and radiotherapy. Contributed papers

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

An International Conference on the Radiological Protection of Patients in Diagnostic and Interventional Radiology, Nuclear Medicine and Radiotherapy organized by the International Atomic Energy Agency and co-sponsored by the European Commission, the Pan American Health Organization and the World Health Organization was held in Malaga, Spain, from 26 to 30 March 2001. The Government of Spain hosted this Conference through the Ministerio de Sanidad y Consumo, the Consejo de Seguridad Nuclear, the Junta de Andalucia, the Universidad de Malaga and the Grupo de Investigacion en Proteccion Radiologica de la Universidad de Malaga (PRUMA). The Conference was organized in co-operation with the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), the International Commission on Radiological Protection (ICRP) and the following professional societies: International Organization of Medical Physicists (IOMP), International Radiation Protection Association (IRPA), International Society of Radiation Oncology (ISRO), International Society of Radiology (ISR), International Society of Radiographers and Radiological Technologists (ISRRT) and World Federation of Nuclear Medicine and Biology (WFNMB). This publication contains contributed papers submitted to the Conference Programme Committee. The papers are in one of the two working languages of this Conference, English and Spanish. The topics covered by the Conference are as follows: Radiological protection of patients in general diagnostic radiology (radiography), Radiological protection of patients in general diagnostic radiology (fluoroscopy), Radiological protection issues in specific uses of diagnostic radiology, such as mammography and computed tomography (with special consideration of the impact of digital techniques), Radiological protection in interventional radiology, including fluoroscopy not carried out by radiologists, Radiological protection of patients in nuclear medicine, Developing and

Occupational radiation protection: Protecting workers against exposure to ionizing radiation. Contributed papers

International Nuclear Information System (INIS)

2003-07-01

objective of the Conference was to foster the exchange of information on current issues related to the exposure of workers to ionizing radiation in the course of their work and to formulate recommendations, as appropriate, regarding measures to strengthen international co-operation in occupational radiation protection. The Conference addressed the issue of establishing occupational radiation protection standards and providing for their application. It will focus on a number of specific problems, inter alia, the complex issue of controlling occupational exposure to natural sources of radiation. This document contain contributed papers to the Conference

Working Paper 2: WDM, Poverty & Equity | IDRC - International ...

International Development Research Centre (IDRC) Digital Library (Canada)

2010-12-08

Dec 8, 2010 ... This paper shows that WDM can contribute to poverty reduction, defined ... Series contributes to setting the stage for the next phase of WDM research. ... that 20% of the country's population has some form of physical disability.

Contribution for study on curing of organic coatings in papers, by electron beam

International Nuclear Information System (INIS)

Taqueda, M.H.S.

1986-01-01

The behaviour of national raw material is studied: paper, resins vamishes used on the surface finishing furniture, when subnitted to electron beam curing in an inert atmosphere. The dosimetric control of the irradiation system was made by using CTA films. The minimum cure dose obtained for the EBC 1650/3009 varnish(national polyester) was 2.4 Mrad and of 2.0 Mrad for the EBC 1650/3010 (imported polyester from Germany). The optimun cure dose for both was 3.0 Mrad. The papers impregnated with EBC varnish of with conventional varnish were measured mechanically for resistance in traction and an evaluation of resistance of the finished surfaces with the ebc varnishes was made. The coatings obtained with the EBC varnishes manufactured nationally were compared with the conventional vamishes of thermal cure and with paper samples impregnated and cured in Germany. (author) [pt

The influence of dynamical friction and mean motion resonances on terrestrial planet growth

Science.gov (United States)

Wallace, Spencer Clark; Quinn, Thomas R.

2018-04-01

We present a set of high-resolution direct N-body simulations of planetesimal coagulation at 1 AU. We follow the evolution of of 1 million planetesimals in a ring though the runaway and oligarchic growth phases. During oligarchic growth, the size frequency distribution (SFD) of planetesimals develops a bump at intermediate masses, which we argue is due to dynamical friction acting through mean motion resonances, heating the low mass planetesimals and inhibiting their growth. This feature is similar to the bump seen in the SFD of asteroid belt and Kuiper belt objects and we argue that a careful treatment of the dynamics of planetesimal interactions is required in order to adequately explain the observed SFD. Although our model does not account for fragmentation, our results show that a similar feature can be produced without it, which is in contention with previous studies.

Uncapacitated facility location problems: contributions

Directory of Open Access Journals (Sweden)

Galvão Roberto Diéguez

2004-01-01

Full Text Available The objective of the present paper is to review my personal contributions in the field of uncapacitated facility location problems. These contributions took place throughout my academic career, from the time I was a Ph.D. student at Imperial College to the present day. They cover approximately 30 years, from 1973 to 2003; they address: algorithms developed for the p-median problem and for a general formulation of uncapacitated location problems; the study of dynamic location models; covering and hierarchical location problems; queuing-based probabilistic location models. The contributions encompass theoretical developments, computational algorithms and practical applications. All work took place in an academic environment, with the invaluable collaboration of colleagues (both in Brazil and abroad and research students at COPPE. Each section in the paper is dedicated to a topic that involves a personal contribution. Every one of them is placed within the context of the existing literature.

Contributions to sampling statistics

CERN Document Server

Conti, Pier; Ranalli, Maria

2014-01-01

This book contains a selection of the papers presented at the ITACOSM 2013 Conference, held in Milan in June 2013. ITACOSM is the bi-annual meeting of the Survey Sampling Group S2G of the Italian Statistical Society, intended as an international  forum of scientific discussion on the developments of theory and application of survey sampling methodologies and applications in human and natural sciences. The book gathers research papers carefully selected from both invited and contributed sessions of the conference. The whole book appears to be a relevant contribution to various key aspects of sampling methodology and techniques; it deals with some hot topics in sampling theory, such as calibration, quantile-regression and multiple frame surveys, and with innovative methodologies in important topics of both sampling theory and applications. Contributions cut across current sampling methodologies such as interval estimation for complex samples, randomized responses, bootstrap, weighting, modeling, imputati...

The Interstellar Medium in External Galaxies: Summaries of contributed papers

Science.gov (United States)

Hollenbach, David J. (Editor); Thronson, Harley A., Jr. (Editor)

1990-01-01

The Second Wyoming Conference entitled, The Interstellar Medium in External Galaxies, was held on July 3 to 7, 1989, to discuss the current understanding of the interstellar medium in external galaxies and to analyze the basic physical processes underlying interstellar phenomena. The papers covered a broad range of research on the gas and dust in external galaxies and focused on such topics as the distribution and morphology of the atomic, molecular, and dust components; the dynamics of the gas and the role of the magnetic field in the dynamics; elemental abundances and gas depletions in the atomic and ionized components; cooling flows; star formation; the correlation of the nonthermal radio continuum with the cool component of the interstellar medium; the origin and effect of hot galactic halos; the absorption line systems seen in distant quasars; and the effect of galactic collisions.

Experts' conference on the Climate and Energy Contribution

International Nuclear Information System (INIS)

2009-06-01

This document first proposes the White Paper prepared for the experts' conference. After a presentation of the Emission Trading System (ETS), this paper highlights the benefit of the introduction of economical instruments rather than regulatory instruments to promote the reduction of greenhouse gas emissions. It underlines the distinction between the proposed 'climate-energy contribution' (or carbon tax) and the Cambridge tax. Then, it describes how to implement such a contribution, i.e. how to define its base, and how to relate it with existing taxes. Some graphs compare the tax rates on fuels, gas and domestic oil in European countries. The paper then defines what the field of application of the contribution could be, how to make this contribution more efficient, and what could be its economical consequences. Then, the document proposes the text of Michel Rocard's intervention on the stakes of conference on this climate-energy contribution

Abstracts of contributed papers. Sixth international conference on high-energy physics and nuclear structure, Santa Fe and Los Alamos, NM, June 9--14, 1975

International Nuclear Information System (INIS)

Mischke, R.; Hargrove, C.; Hoffman, C.

1975-08-01

Abstracts of contributed papers are assembled under the following headings (number denotes the number of abstracts in the section): pi p and pi d interactions (10); π nucleus theory (33); intermediate isobar calculations (8); π-nucleus interactions (25); stopping muons (44); exotic atoms and condensed nuclear states (28); nucleus-nucleus interactions (31); nuclear structure and hypernuclei (7); nucleon-nucleon interactions (24); e- and γ-nucleus interactions (29); weak interactions (17); high energy collisions (13); heavy ions (22); instrumentation (8). (SDF)

Papers on the nuclear regulatory dilemma

Energy Technology Data Exchange (ETDEWEB)

Barkenbus, J.N.; Freeman, S.D.; Weinberg, A.M.

1985-10-01

The four papers contained in this report are titled: (1) From Prescriptive to Performance-Based Regulation of Nuclear Power; (2) Nuclear Regulatory Reform: A Technology-Forcing Approach; (3) Improving the Regulation of Nuclear Power; and (4) Science and Its Limits: The Regulators' Dilemma. These four papers investigate issues relating to the long-term regulation of nuclear energy. They were prepared as part of the Institute for Energy Analysis' project on Nuclear Regulation funded by a grant from the Mellon Foundation and a smaller grant by the MacArthur Foundation. Originally this work was to be supplemented by contributions from the Nuclear Regulatory Commission and from the Department of Energy. These contributions were not forthcoming, and as a result the scope of our investigations was more restricted than we had originally planned.

Papers on the nuclear regulatory dilemma

International Nuclear Information System (INIS)

Barkenbus, J.N.; Freeman, S.D.; Weinberg, A.M.

1985-10-01

The four papers contained in this report are titled: (1) From Prescriptive to Performance-Based Regulation of Nuclear Power; (2) Nuclear Regulatory Reform: A Technology-Forcing Approach; (3) Improving the Regulation of Nuclear Power; and (4) Science and Its Limits: The Regulators' Dilemma. These four papers investigate issues relating to the long-term regulation of nuclear energy. They were prepared as part of the Institute for Energy Analysis' project on Nuclear Regulation funded by a grant from the Mellon Foundation and a smaller grant by the MacArthur Foundation. Originally this work was to be supplemented by contributions from the Nuclear Regulatory Commission and from the Department of Energy. These contributions were not forthcoming, and as a result the scope of our investigations was more restricted than we had originally planned

Contribution to a Theory of Detailed Design

DEFF Research Database (Denmark)

Mortensen, Niels Henrik

1999-01-01

It has been recognised, that literature actually do not propose a theory of detailed design. In this paper a theory contribution is proposed, linking part design to organ design and allowing a type of functional reasoning. The proposed theory satisfies our need for explaining the nature of a part...... structure, for support of synthesis of part structure, i.e. detailed design, and our need for digital modelling of part structures.The aim of this paper is to contribute to a design theory valid for detailed design. The proposal is based upon the theory's ability to explain the nature of machine parts...... and assemblies, to support the synthesis of parts and to allow the modelling, especially digital modelling of a part structure. The contribution is based upon Theory of Technical Systems, Hubka, and the Domain Theory, Andreasen. This paper is based on a paper presented at ICED 99, Mortensen, but focus...

Percentage-based Author Contribution Index: a universal measure of author contribution to scientific articles.

Science.gov (United States)

Boyer, Stéphane; Ikeda, Takayoshi; Lefort, Marie-Caroline; Malumbres-Olarte, Jagoba; Schmidt, Jason M

2017-01-01

Deciphering the amount of work provided by different co-authors of a scientific paper has been a recurrent problem in science. Despite the myriad of metrics available, the scientific community still largely relies on the position in the list of authors to evaluate contributions, a metric that attributes subjective and unfounded credit to co-authors. We propose an easy to apply, universally comparable and fair metric to measure and report co-authors contribution in the scientific literature. The proposed Author Contribution Index (ACI) is based on contribution percentages provided by the authors, preferably at the time of submission. Researchers can use ACI to compare the contributions of different authors, describe the contribution profile of a particular researcher or analyse how contribution changes through time. We provide such an analysis based on contribution percentages provided by 97 scientists from the field of ecology who voluntarily responded to an online anonymous survey. ACI is simple to understand and to implement because it is based solely on percentage contributions and the number of co-authors. It provides a continuous score that reflects the contribution of one author as compared to the average contribution of all other authors. For example, ACI(i) = 3, means that author i contributed three times more than what the other authors contributed on average. Our analysis comprised 836 papers published in 2014-2016 and revealed patterns of ACI values that relate to career advancement. There are many examples of author contribution indices that have been proposed but none has really been adopted by scientific journals. Many of the proposed solutions are either too complicated, not accurate enough or not comparable across articles, authors and disciplines. The author contribution index presented here addresses these three major issues and has the potential to contribute to more transparency in the science literature. If adopted by scientific journals, it

Social Contributions in Romania

Directory of Open Access Journals (Sweden)

Attila Gyorgy

2012-12-01

Full Text Available Social contributions have an important impact on payroll policy. Also, social contributions represent a significant budgetary revenue item which can be viewed at the edge between taxation and insurance. Social contributions in Romania experienced many changes which ended in 2008. Nowadays, they are within a long transaction period towards partial externalization of the insurance activity to privately managed funds. The aim of this paper is to analyse the homogeneity of Romanian social security public scheme using annual data extracted from 2002-2009.The main findings reveal that social contributions reached the pinnacle of diversification, being too many, some of them with a small contribution rates; fiscal reforms which reduced contribution rates advantaged employers, and state will be interested to externalize this activity as far private sector will be able to assume this responsibility and the budgetary effects are acceptable for the public finance.

MODELING THE FORMATION OF GIANT PLANET CORES. I. EVALUATING KEY PROCESSES

International Nuclear Information System (INIS)

Levison, Harold F.; Thommes, Edward; Duncan, Martin J.

2010-01-01

One of the most challenging problems we face in our understanding of planet formation is how Jupiter and Saturn could have formed before the solar nebula dispersed. The most popular model of giant planet formation is the so-called core accretion model. In this model a large planetary embryo formed first, mainly by two-body accretion. This is then followed by a period of inflow of nebular gas directly onto the growing planet. The core accretion model has an Achilles heel, namely the very first step. We have undertaken the most comprehensive study of this process to date. In this study, we numerically integrate the orbits of a number of planetary embryos embedded in a swarm of planetesimals. In these experiments, we have included a large number of physical processes that might enhance accretion. In particular, we have included (1) aerodynamic gas drag, (2) collisional damping between planetesimals, (3) enhanced embryo cross sections due to their atmospheres, (4) planetesimal fragmentation, and (5) planetesimal-driven migration. We find that the gravitational interaction between the embryos and the planetesimals leads to the wholesale redistribution of material-regions are cleared of material and gaps open near the embryos. Indeed, in 90% of our simulations without fragmentation, the region near those embryos is cleared of planetesimals before much growth can occur. Thus, the widely used assumption that the surface density distribution of planetesimals is smooth can lead to misleading results. In the remaining 10% of our simulations, the embryos undergo a burst of outward migration that significantly increases growth. On timescales of ∼10 5 years, the outer embryo can migrate ∼6 AU and grow to roughly 30 M + . This represents a largely unexplored mode of core formation. We also find that the inclusion of planetesimal fragmentation tends to inhibit growth except for a narrow range of fragment migration rates.

Spring 1991 Meeting outstanding papers

Science.gov (United States)

The Atmospheric Sciences Committee has presented Kaye Brubaker and Jichun Shi with Outstanding Student Paper awards for presentations given at the AGU 1991 Spring Meeting, held in Baltimore May 28-31.Brubaker's paper, “Precipitation Recycling Estimated from Atmospheric Data,” presented quantitative estimates of the contribution of locallyevaporated moisture to precipitation over several large continental regions. Recycled precipitation is defined as water that evaporates from the land surface of a specified region and falls again as precipitation within the region. Brubaker applied a control volume analysis based on a model proposed by Budyko.

An Analysis of the "Classic" Papers in Aesthetic Surgery.

Science.gov (United States)

Joyce, Cormac W; Joyce, K M; Kelly, John C; Kelly, Jack L; Carroll, Sean M; Sugrue, Conor

2015-02-01

Over the past 50 years, there has been a significant increase in published articles in the medical literature. The aesthetic surgery literature is vast, consisting of a plethora of diverse articles written by a myriad of illustrious authors. Despite this considerable archive of published material, it remains nebulous as to which precise papers have had the greatest impact on our specialty. The aim of our study was to identify and analyse the characteristics of the top 50 papers in the field of aesthetic surgery in the published literature. The 50 most cited papers were identified in several surgical journals through the Web of Science. The articles were ranked in order of the number of citations received. These classic 50 papers were analysed for article type, their journal distribution, level of evidence as well as geographic and institutional origin. Six journals contributed to the top 50 papers in aesthetic surgery with Plastic and Reconstructive Surgery contributing the most with 31 papers.

Low doses of ionizing radiation: Biological effects and regulatory control. Contributed papers

International Nuclear Information System (INIS)

1997-11-01

The International Atomic Energy Agency and the World Health Organization, in cooperation with the United Nations Scientific Committee on the Effects of Atomic Radiation, organized an international conference on Low Doses of Ionizing Radiation: Biological Effects and Regulatory Control, held in seville, Spain, from 17 to 21 November 1997. This technical document contains concise papers submitted to the conference

Low doses of ionizing radiation: Biological effects and regulatory control. Contributed papers

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-11-01

The International Atomic Energy Agency and the World Health Organization, in cooperation with the United Nations Scientific Committee on the Effects of Atomic Radiation, organized an international conference on Low Doses of Ionizing Radiation: Biological Effects and Regulatory Control, held in seville, Spain, from 17 to 21 November 1997. This technical document contains concise papers submitted to the conference. Refs, figs, tabs.

Paper reutilization to manufacture plasterboard

International Nuclear Information System (INIS)

Calixto, M.K.; Medeiros, I.A.; Lima, R.C.; Araujo, Y.C.F.; Lima, E.M.C. de

2016-01-01

The changes in the planet have accelerated the discussion about environmental preservation and the pursuit for sustainable solutions aiming the human development. In the civil construction, the residue recovery, not only contribute to sustainability but also relieves the consumption of raw material and for all this the search for new products in this new twist is in the center of global technological research. The goal of this work is to obtain plasterboard incorporating discarded paper in the educational environment. In this study, the plaster was characterized initially by X-ray diffraction and thermals analysis (TG e DTA). It was prepared a paste of plaster and processed paper varying the paper amount in two proportions with 10% and 50% respectively, and was utilized the plaster/water factor equals to 0,7. The plaster - paper mixtures were characterized about the setting time and compressive strength. The results indicated that the increase in paper content led to the decreased resistance. (author)

Nuclear Structure: Dubna Symposium 1968. Invited Papers from the International Symposium on Nuclear Structure

International Nuclear Information System (INIS)

1968-01-01

Invited papers of a Symposium organized by the Joint Institute for Nuclear Research, Dubna, supported by IUPAP and IAEA, and held in Dubna from 4 to 11 July 1968. The meeting was attended by about 450 scientists from 30 countries. The volume contains the invited papers, all by distinguished scientists, and the discussions and short contributions that followed the presentation of these papers. Contents: I. Nuclear structure at low excitations (15 papers) ; II. Nuclear structure at high excitations (6 papers): III. Open problems in nuclear physics (3 papers); IV. Equilibrium deformations (6 papers); V. General properties of nuclei (6 papers); VI. Closing remarks; List of contributions; List of seminar papers; List of participants; Author index. All papers, discussions and short contributions are in English; the abstracts are in English and Russian, which were the working languages of the Symposium. (author)

Nuclear shapes and nuclear structure at low excitation energies. Abstracts of contributed papers

International Nuclear Information System (INIS)

Dykstra, F.; Goutte, D.; Sauvage, J.; Vergnes, M.

1994-01-01

103 papers are presented on recent theoretical and experimental results on nuclear structure investigation. Short communications were published in this volume, all of which were indexed separately for the INIS database. (R.P.)

Internet access to scanned paper documents

NARCIS (Netherlands)

Worring, M.; Smeulders, A.W.M.; Witten, I.; Akscyn, R.; Shipman, F.M.

1998-01-01

In this contribution we identify the different structures to encounterin a hyperdocument. Methods are described for deriving those structures from scanned paper originals. The content and structure of the document is then made available in a form suited for an Internet browser. It provides

Development and Assessment of Collaboration, Teamwork, and Communication. TLTC Paper No. 4. CRLT Occasional Paper No. 35

Science.gov (United States)

Kusano, Stephanie M.; Conger, Amy J.; Wright, Mary C.

2016-01-01

This Occasional Paper focuses on fostering and assessing collaboration, teamwork, and communication. This involves encouraging students to appreciate and leverage diverse contributions to a task, developing their ability to cooperate with others towards common purposes, and increasing their capacity to communicate effectively with teammates,…

Growth of planetisimals in a gaseous ring

International Nuclear Information System (INIS)

Hourigan, K.

1981-01-01

The aggregation of planetesimals in a gaseous ring leads to the development of a dominant body amongst the planetesimal population. The presence of the gas in the form of a differentially rotating ring serves to constrain the orbits of the planetesimals and grains to within a thin toroidal region through the action of gas drag. This situation allows for the efficient aggregation of bodies and, as a result of the low resultant relative velocites, the minimization of collisional fragmentation effects

The contribution of epidemiology

NARCIS (Netherlands)

Brandt, P. van den; Voorrips, L.; Hertz-Picciotto, I.; Shuker, D.; Boeing, H.; Speijers, G.; Guittard, C.; Kleiner, J.; Knowles, M.; Wolk, A.; Goldbohm, A.

2002-01-01

Epidemiologic studies directly contribute data on risk (or benefit) in humans as the investigated species, and in the full food intake range normally encountered by humans. This paper starts with introducing the epidemiologic approach, followed by a discussion of perceived differences between

TRANSPORTATION RESEARCH CONTRIBUTIONS TO SOCIETY BY UNIVERSITY TRANSPORTATION CENTERS

Directory of Open Access Journals (Sweden)

Robert C. JOHNS

2003-01-01

Full Text Available This paper discusses the importance of knowledge in the global economy and reviews the process in which knowledge is applied to develop innovations. It confirms the importance of innovation as a key factor for success in today's competitive environment. The paper discusses the contributions a university can make to the innovation process in the field of transportation, and offers a vision of how a university center can enhance and facilitate these contributions. It then describes the efforts of one center, including three examples of innovations facilitated by the center in traffic detection, regional planning, and pavement management. The paper concludes with suggestions that would strengthen the societal contributions of university transportation centers.

Renewable energy sources. European Commission papers

International Nuclear Information System (INIS)

1997-05-01

The ''Directive on the Promotion of Electricity from Renewable Sources of Energy in the Internal Electricity Market'' was adopted in September 2001. Its purpose is to promote an increase in the contribution of renewable energy sources to electricity production in the internal market for electricity and to create a basis for a future Community framework. Energie-Cites provides in this document a summary of its opinion on the Green Paper and on Alterner II and gives a proposal for an Action Plan concerning the White Paper. (A.L.B.)

NIFS contributions to 19th IAEA fusion energy conference

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-11-01

NIFS has presented 21 papers at the 19th IAEA Fusion Energy Conference (Lyon, France, 14-19 October 2002). The contributed papers are collected in this report. The 21 papers are indexed individually. (J.P.N.)

C. Huang , G. Zhao , HW Zhang & YQ Chen

Indian Academy of Sciences (India)

the host stars' birth cloud with higher abundance of Si will make the cloud ... with the metallicity distribution of nearby field F, G, or K stars which are known to .... In the early stage of planetesimal accumulation, the rate of growth of planetesimal.

Contributions from Women to the Radiation Sciences: A Brief History.

Science.gov (United States)

Martinez, Nicole E

2017-04-01

Contributions from men to radiation science are well known, particularly the early contributions from such luminaries as William Roentgen, James Chadwick, Niels Bohr, Robert Oppenheimer, and the like. Although not ignored per se, beyond Marie Curie and Lise Meitner, the contributions of female nuclear scientists are not as widely recognized. This paper provides a concise historical summary of contributions to radiation science from the discovery of radiation through the current status of international leadership within the radiation protection community. Beyond lead scientists and academics, this paper also considers support personnel as well as the role women have played in the advancement of radiation epidemiology.

How sonochemistry contributes to green chemistry?

Science.gov (United States)

Chatel, Gregory

2018-01-01

Based on the analyses of papers from the literature, and especially those published in Ultrasonics Sonochemistry journal, the contribution of sonochemistry to green chemistry area has been discussed here. Important reminders and insights on the good practices and considerations have been made to understand and demonstrate how sonochemistry can continue to efficiently contribute to green chemistry area in the further studies. Copyright © 2017 Elsevier B.V. All rights reserved.

Non-leading contributions in QCD: Summing the perturbative series

International Nuclear Information System (INIS)

Trentadue, L.

1984-01-01

This paper presents the results of a systematic analysis of the leading and non-leading contributions in perturbative QCD and addresses the question of logarithmic contributions to all orders of the perturbative series

Working Paper 2: Enhancing the migration experience: gendering ...

International Development Research Centre (IDRC) Digital Library (Canada)

2010-12-13

Dec 13, 2010 ... ... migrant women dominate certain 'sectors,' which have traditionally been outside ... In an effort to contribute to filling this research gap, this paper aims to ... Highlight: Ankara workshop puts minimum wage on the G-20 radar.

Position Paper on Intelligent Supply Chains

DEFF Research Database (Denmark)

Møller, Charles

This paper is intended to present and to analyze the concept of the Intelligent Supply Chain (ISC). The purpose of the paper is to: 1) Clarify the concept of the intelligent supply chain; 2) Identify emerging research opportunities; and 3) Specify a research engagement model for further explorati...... of intelligent supply chains. It is concluded that information management is critical to intelligent supply chains and a research agenda is outlined.......This paper is intended to present and to analyze the concept of the Intelligent Supply Chain (ISC). The purpose of the paper is to: 1) Clarify the concept of the intelligent supply chain; 2) Identify emerging research opportunities; and 3) Specify a research engagement model for further exploration...... the concept of Intelligent Supply Chain and to establish an overall perspective based on information management. The claim made here is that the notion of the intelligent enterprise contributes with a new perspective on supply chain management that addresses the current challenges in an industrial supply...

On the contribution of reclaimed wastewater irrigation to the potential exposure of humans to antibiotics, antibiotic resistant bacteria and antibiotic resistance genes - NEREUS COST Action ES1403 position paper

DEFF Research Database (Denmark)

Piña, Benjamin; Bayona, Josep M.; Christou, Anastasis

2018-01-01

Antibiotic resistance (AR) is becoming a worldwide threat due to the increasing occurrence of antibiotic-resistant pathogenic bacterial strains. There is a general consensus about the potential implications of the use of antibiotics in livestock on the onset of antibiotic resistant bacteria (ARB......), mainly through meat consumption. However, the ever-increasing use of reclaimed wastewater (RWW) in agriculture may also contribute significantly to the non-accounted exposure to antibiotics, ARB, and antibiotic resistance genes (ARGs). This position paper aims at evaluating the current knowledge...... concerning the occurrence of antibiotics, ARBs, and ARGs in edible parts of different common crops irrigated with RWW. We will discuss which regulations on the use of RWW may contribute to the minimization of the prevalence of these contaminants in crops, and provide recommendations on how to minimize...

Gas Mitigation in Paper Production

Science.gov (United States)

Santos, AS; Bittencourt, C.

2017-07-01

The Brazilian paper industry has competitive advantages offered by the favorable climate, which favors an increase in the yield of forest restoration, and consequently, in the productive process. On the other hand, following the greenhouse gases (GHG), we can see our constantly changing sun, causing the solar storms, allowing their prevention or mitigating measures. The objective of this work is to contribute to the construction of the understanding necessary for the reduction of GHG emission from a preliminary analysis of the pulp and paper sector. As a secondary objective, the text preliminarily analyzes a company’s behavior against the backdrop of the Paris Accord, which strengthens the global response to the threat of climate change and strengthens the capacity of countries to deal with the impacts of such changes. The identification of best practices in the pulp and paper industry is understood, focusing on environmental sustainability, such as the adoption of reforestation, obtaining significant results. In the case of the paper industry, the management of public forests for sustainable production, within the structure of the Ministry of the Environment, establishes the promotion of public awareness about the importance of conservation, recovery and sustainable management of forest resources.

Normalized Paper Credit Assignment: A Solution for the Ethical Dilemma Induced by Multiple Important Authors.

Science.gov (United States)

Fang, Hui

2017-09-21

With the growth of research collaborations, the average number of authors per article and the phenomenon of equally important authorships have increased. The essence of the phenomenon of equally important authorships is the approximately equal importance of authors, both because of the difficulties in comparing authors' contributions to a paper and some actual research evaluation practices, which (approximately) give full paper credit only to the most important authors. A mechanism for indicating that various authors contributed equally is required to maintain and strengthen collaboration. However, the phenomenon of multiple important authors can cause unfair comparisons among the research contributions and abilities of authors of different papers. This loophole may be exploited. Normalizing the credit assigned to a given paper's authors is an easy way to solve this ethical dilemma. This approach enables fair comparisons of the contributions by the authors of different articles and suppresses unethical behaviour in author listings. Bibliometric researchers have proposed mature methods of normalized paper credit assignment that would be easy to use given the current level of computer adoption.

Free radicals induced archive paper by irradiation

International Nuclear Information System (INIS)

Cutrubinis, M.; Moise, I.V.; Negut, C.D.; Georgescu, R.; Suvaila, R.; Virgolici, M.; Manea, M.M.

2011-01-01

Complete text of publication follows. Irradiation of archive paper (document archives of institutions, companies etc. and library or museum collections of books and documents) can solve the problems related to the bio-deterioration and bio-contamination of paper and sometimes save valuable cultural heritage paper items. For valuable paper items care should be taken to the degradation induced instantly by the ionising radiation to the cellulosic support and also to the long term post-irradiation effects. The free radicals formed due to the irradiation treatment could contribute to instant degradation of paper. Part of them are also trapped for months and years after irradiation and they could be related to the post-irradiation effects in paper items. In this study, different sorts of cellulosic support samples (soft wood and hard wood cellulose, contemporary paper, paper from archives and from collections etc.) have been irradiated with dosis up to 100 kGy and the radiation induced free radicals have been measured by ESR spectrometry. The ESR signals have shown the type and quantity of radiation induced free radicals. Their study can be used for a realistic estimation of the degradative effect of the ionising radiation treatment of archive paper.

Metalicidad de estrellas con exoplanetas y discos de polvo

OpenAIRE

Petrucci, Romina Paola; Saffe, Carlos; Jofré, E.

2017-01-01

We present an uniform comparison among three different kind of objects: cool-Jupiter exoplanet host-stars, stars with dust disks and exoplanet host-stars with dust disks. The goal of this contribution was to determine why stellar objects originally surrounded by planetesimals evolve to different final configurations, from stars with planets to stars with debris disks. Realizamos una comparación uniforme de las metalicidades de tres grupos de objetos diferentes: estrellas con planetas del t...

An Evaluation of a Language for Paper-based Form Sketching

DEFF Research Database (Denmark)

Farruglia, Phillip; Borg, Johnathan; Camilleri, K.P.

2006-01-01

form idea. The research disclosed in this paper is aimed at combining the benefits of paper-based freehand sketches with those of three-dimensional (3D) models. More specifically, this paper reports the on-going development of a prescribed sketching language (PSL) required to create a seamless link...... between paper-based form sketching and CAGM systems. Evaluation results revealed that whilst PSL is easy-to-learn, yet it requires improvements. Such a sketching language contributes a step towards simulating early form design solutions by the combined use of paper-based sketches and 3D models....

Intergenerational Practice: Contributing to a Conceptual Framework

Science.gov (United States)

Vieira, Sacha; Sousa, Liliana

2016-01-01

The ageing of the European population is creating a new demographic mix, increasing the relevance of intergenerational practice (IGP). To date, however, this field lacks an appropriate conceptual framework. This study aims to contribute to such a framework through an integrative review of peer-reviewed papers reporting on IGPs. Fifteen papers were…

The 2006 French Law - A Contribution to a European Policy? - Conference papers

International Nuclear Information System (INIS)

Fischer, Claude; Linkohr, Rolf; Dupraz, Bernard; Gonnot, Francois-Michel; Sido, Bruno; Vassaux, Alain; Golan, Paul; Leclere, Robert; Rycroft, Jeremy; Seppaelae, Timo

2006-01-01

On 28 June, the French 2006 law on the sustainable management of radioactive waste and materials was promulgated, after 15 years of research required by the Bataille law. What are the progresses stemming from this law? The next steps? What do the various French stakeholders, elected officials, trade unions and firms think about it? How is it perceived out of our borders? Can it be a contribution to a European policy? What are the progresses in the other Member States and what lessons can we draw from those? The management of radioactive waste is a question that goes far beyond the national framework of each country, and that must be treated as a priority, whatever the future energy policy. Since 2003, the 'Entretiens europeens' have engaged a dialogue between stakeholders of various socio-professional backgrounds from several countries and with the European Commission, in order to compare the selected options of management and to emphasize the best experiments, which could inspire an innovating European policy in the world. This fourth edition is intended to provide an updated State-of-play of the reflexions on these issues. These proceedings are organized as follows: 1 - Opening Address; 2 - first Round Table: The 2006 Law, What do French Stakeholders Think of it?; 3 - second Round table: The 2006 law, Information for national and Community policies; 4 - Debate between the participants and the audience

Bisphenol A and replacements in thermal paper: A review.

Science.gov (United States)

Björnsdotter, Maria K; de Boer, Jacob; Ballesteros-Gómez, Ana

2017-09-01

Thermal paper contains potentially toxic compounds such as bisphenol A (BPA), which is used as a color developer. BPA has been reported in thermal paper in concentrations up to 42,600 μg g -1 . The exposure to BPA via dermal transfer has been recently discussed as a significant contribution to the overall human exposure and the estimated daily intake (EDI) has been reported up to 218 μg d -1 . BPA has been also detected in recycled paper with concentrations up to 46 μg g -1 . Due to the fact that BPA is a known endocrine disruptor and migrates from materials, regulatory restrictions have been established to prevent risks for the human health. As a consequence, structural analogues, such as bisphenol S (BPS) have been introduced into the market. Little is known about the presence and toxicity of these emerging replacements, and concern has risen about them. The present review gives an overview of the occurrence and levels of BPA and replacements in thermal paper. BPA is still the most common color developer found in thermal paper, followed by BPS. The analytical methods used for quantification of BPA and BPA replacements in paper products are also reviewed. BPA is transferred from thermal paper products to the finger pads upon handling it. Paper-skin transfer followed by penetration of BPA depends on conditions (e.g. greasiness of fingers and use of hand cream). It is, however, still debated whether thermal paper as a source for human exposure contributes significantly to the overall internal BPA exposure. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Roles of Conference Papers in IS

DEFF Research Database (Denmark)

Lanamäki, Arto; Persson, John Stouby

2016-01-01

Information Systems (IS) research has both a journal-oriented publication culture and a rich plethora of conferences. It is unclear why IS researchers even bother with conference publishing given the high focus on journals. Against this backdrop, the purpose of this paper is to increase our...... understanding of conference papers in IS and the role they play for the authoring researchers. We present the first analysis of the papers published during the first six years (2010-2015) in the Scandinavian Conference on Information Systems (SCIS). We conducted interviews with ten SCIS authors. Following...... a framework adopted from Åkerlind [1], we identified how SCIS papers have the roles of fulfilling requirements, establishing oneself, developing personally, enabling change, and other roles. This article contributes to the reflection literature on the IS field by applying a practice lens to understand...

Universities’ contributions to social innovation: reflections in theory & practice

NARCIS (Netherlands)

Benneworth, Paul Stephen; Cunha, Jorge

2015-01-01

Purpose – The purpose of this paper is to resolve a tension in understanding how universities contribute to knowledge-based urban development (KBUD). Design/methodology/approach – The paper is a conceptual paper, which analyses the tension as emerging between the university and the wider societal

Training and Support for Women's Entrepreneurship. ETF Working Paper

Science.gov (United States)

Bekh, Olena

2014-01-01

This paper contributes to the wider efforts of policy makers, experts and practitioners to maximise the contribution of women into the national, regional and global economic growth and competitiveness in the countries neighbouring the European Union (EU). It focuses on actions that can support women's participation in entrepreneurship. The paper…

Number theory and modular forms papers in memory of Robert A Rankin

CERN Document Server

Ono, Ken

2003-01-01

Robert A. Rankin, one of the world's foremost authorities on modular forms and a founding editor of The Ramanujan Journal, died on January 27, 2001, at the age of 85. Rankin had broad interests and contributed fundamental papers in a wide variety of areas within number theory, geometry, analysis, and algebra. To commemorate Rankin's life and work, the editors have collected together 25 papers by several eminent mathematicians reflecting Rankin's extensive range of interests within number theory. Many of these papers reflect Rankin's primary focus in modular forms. It is the editors' fervent hope that mathematicians will be stimulated by these papers and gain a greater appreciation for Rankin's contributions to mathematics. This volume would be an inspiration to students and researchers in the areas of number theory and modular forms.

Planetary Formation and Dynamics in Binary Systems

Science.gov (United States)

Xie, J. W.

2013-01-01

As of today, over 500 exoplanets have been detected since the first exoplanet was discovered around a solar-like star in 1995. The planets in binaries could be common as stars are usually born in binary or multiple star systems. Although current observations show that the planet host rate in multiple star systems is around 17%, this fraction should be considered as a lower limit because of noticeable selection effects against binaries in planet searches. Most of the current known planet-bearing binary systems are S-types, meaning the companion star acts as a distant satellite, typically orbiting the inner star-planet system over 100 AU away. Nevertheless, there are four systems with a smaller separation of 20 AU, including the Gamma Cephei, GJ 86, HD 41004, and HD 196885. In addition to the planets in circumprimary (S-type) orbits discussed above, planets in circumbinary (P-type) orbits have been found in only two systems. In this thesis, we mainly study the planet formation in the S-type binary systems. In chapter 1, we first summarize current observational facts of exoplanets both in single-star and binary systems, then review the theoretical models of planet formation, with special attention to the application in binary systems. Perturbative effects from stellar companions render the planet formation process in binary systems even more complex than that in single-star systems. The perturbations from a binary companion can excite planetesimal orbits, and increase their mutual impact velocities to the values that might exceed their escape velocity or even the critical velocity for the onset of eroding collisions. The intermediate stage of the formation process---from planetesimals to planetary embryos---is thus the most problematic. In the following chapters, we investigate whether and how the planet formation goes through such a problematic stage. In chapter 2, we study the effects of gas dissipation on the planetesimals' mutual accretion. We find that in a

International conference on challenges faced by technical and scientific support organizations in enhancing nuclear safety. Contributed papers and presentations

International Nuclear Information System (INIS)

2007-01-01

conclusions apply equally to TSOs, since their expertise is an integral part of supporting the regulatory decision making process over the entire life cycle of facilities and activities for the continuous improvement of safety. On the basis of the presentations and discussions, the conference developed conclusions as well as recommendations for consideration by TSOs, regulatory authorities, national governments, relevant international and regional organizations, the nuclear industry and other stakeholders. This CD-ROM contains the unedited contributed papers and the presentations that were submitted with some of the invited papers. A record of the conference including a summary, the opening speeches, the invited papers, and the conclusions and summary of the conference by the President are available in the printed STI/PUB-1301

Does globalization contribute to economic growth in developing ...

African Journals Online (AJOL)

This paper examines empirically whether or not globalization contributes to economic growth in developing countries, drawing empirical lessons from Nigeria. The globalization – growth link, is anchored on Husain Schematic representation, Solow model, and the new growth (endogenous growth) theory. The paper adopts ...

The Collected Works of Eugene Paul Wigner the Scientific Papers

CERN Document Server

Wigner, Eugene Paul

1993-01-01

Eugene Wigner is one of the few giants of 20th-century physics His early work helped to shape quantum mechanics, he laid the foundations of nuclear physics and nuclear engineering, and he contributed significantly to solid-state physics His philosophical and political writings are widely known All his works will be reprinted in Eugene Paul Wigner's Collected Workstogether with descriptive annotations by outstanding scientists The present volume begins with a short biographical sketch followed by Wigner's papers on group theory, an extremely powerful tool he created for theoretical quantum physics They are presented in two parts The first, annotated by B Judd, covers applications to atomic and molecular spectra, term structure, time reversal and spin In the second, G Mackey introduces to the reader the mathematical papers, many of which are outstanding contributions to the theory of unitary representations of groups, including the famous paper on the Lorentz group

Extreme secular excitation of eccentricity inside mean motion resonance. Small bodies driven into star-grazing orbits by planetary perturbations

Science.gov (United States)

Pichierri, Gabriele; Morbidelli, Alessandro; Lai, Dong

2017-09-01

Context. It is well known that asteroids and comets fall into the Sun. Metal pollution of white dwarfs and transient spectroscopic signatures of young stars like β-Pic provide growing evidence that extra solar planetesimals can attain extreme orbital eccentricities and fall into their parent stars. Aims: We aim to develop a general, implementable, semi-analytical theory of secular eccentricity excitation of small bodies (planetesimals) in mean motion resonances with an eccentric planet valid for arbitrary values of the eccentricities and including the short-range force due to General Relativity. Methods: Our semi-analytic model for the restricted planar three-body problem does not make use of series expansion and therefore is valid for any eccentricity value and semi-major axis ratio. The model is based on the application of the adiabatic principle, which is valid when the precession period of the longitude of pericentre of the planetesimal is much longer than the libration period in the mean motion resonance. In resonances of order larger than 1 this is true except for vanishingly small eccentricities. We provide prospective users with a Mathematica notebook with implementation of the model allowing direct use. Results: We confirm that the 4:1 mean motion resonance with a moderately eccentric (e' ≲ 0.1) planet is the most powerful one to lift the eccentricity of planetesimals from nearly circular orbits to star-grazing ones. However, if the planet is too eccentric, we find that this resonance is unable to pump the planetesimal's eccentricity to a very high value. The inclusion of the General Relativity effect imposes a condition on the mass of the planet to drive the planetesimals into star-grazing orbits. For a planetesimal at 1 AU around a solar mass star (or white dwarf), we find a threshold planetary mass of about 17 Earth masses. We finally derive an analytical formula for this critical mass. Conclusions: Planetesimals can easily fall into the central star

Contribution inequality in the spatial public goods game: Should the rich contribute more?

Science.gov (United States)

Tu, Jing

2018-04-01

Scale-free property exists in resource distribution, and the rich pay more in public goods is commonplace in reality. What will happen if the rich are expected to contribute more in the spatial public goods game? This paper therefore proposes a new contribution paradigm, in which individual contribution is determined by his payoff in the last evolution step. Tunable parameter w is used to characterize the contribution rate of nodes whose payoff is larger than the average. The results of simulations reveal that the impact of w on cooperation is associated with the enhancement factor r. When r is low, the higher w is, the lower the cooperation rate is. With the increment of r, the value of w to optimize cooperation rate increases with r. The relationship of cooperation rate and wealth on the network has also been investigated. Interestingly, higher cooperation rate does not always lead to higher wealth. Finally, the impact of w on the wealth distribution on the network is explored. The higher w reduces the inequality in wealth distribution by the shrinking of lower-class, which is enhanced by a higher r.

B. F. Skinner's Contributions to Applied Behavior Analysis

Science.gov (United States)

Morris, Edward K.; Smith, Nathaniel G.; Altus, Deborah E.

2005-01-01

Our paper reviews and analyzes B. F. Skinner's contributions to applied behavior analysis in order to assess his role as the field's originator and founder. We found, first, that his contributions fall into five categorizes: the style and content of his science, his interpretations of typical and atypical human behavior, the implications he drew…

Shear Strength of Concrete I-Beams - Contributions of Flanges

DEFF Research Database (Denmark)

Teoh, B. K.; Hoang, Cao Linh; Nielsen, Mogens Peter

1999-01-01

The contribution of flanges to the shear strength of reinforced concrete beams has up to now either been neglected or evaluated by very simple empirical formulas. However, the contribution may sometimes be large, up to 20-30%. In this paper the flange contribution for shear reinforced I-beams has...... range of geometrical parameters. The comparisons show that the method suggested does indeed lead to very accurate results....

Contributing to Functionality

DEFF Research Database (Denmark)

Törpel, Bettina

2006-01-01

The objective of this paper is the design of computer supported joint action spaces. It is argued against a view of functionality as residing in computer applications. In such a view the creation of functionality is equivalent to the creation of computer applications. Functionality, in the view...... advocated in this paper, emerges in the specific dynamic interplay of actors, objectives, structures, practices and means. In this view, functionality is the result of creating, harnessing and inhabiting computer supported joint action spaces. The successful creation and further development of a computer...... supported joint action space comprises a whole range of appropriate design contributions. The approach is illustrated by the example of the creation of the computer supported joint action space "exchange network of voluntary union educators". As part of the effort a group of participants created...

National contributions to observed global warming

International Nuclear Information System (INIS)

Matthews, H Damon; Graham, Tanya L; Keverian, Serge; Lamontagne, Cassandra; Seto, Donny; Smith, Trevor J

2014-01-01

There is considerable interest in identifying national contributions to global warming as a way of allocating historical responsibility for observed climate change. This task is made difficult by uncertainty associated with national estimates of historical emissions, as well as by difficulty in estimating the climate response to emissions of gases with widely varying atmospheric lifetimes. Here, we present a new estimate of national contributions to observed climate warming, including CO 2 emissions from fossil fuels and land-use change, as well as methane, nitrous oxide and sulfate aerosol emissions While some countries’ warming contributions are reasonably well defined by fossil fuel CO 2 emissions, many countries have dominant contributions from land-use CO 2 and non-CO 2 greenhouse gas emissions, emphasizing the importance of both deforestation and agriculture as components of a country’s contribution to climate warming. Furthermore, because of their short atmospheric lifetime, recent sulfate aerosol emissions have a large impact on a country’s current climate contribution We show also that there are vast disparities in both total and per-capita climate contributions among countries, and that across most developed countries, per-capita contributions are not currently consistent with attempts to restrict global temperature change to less than 2 °C above pre-industrial temperatures. (paper)

Unacknowledged contributions of Pavlov and Barcroft to Cannon's theory of homeostasis.

Science.gov (United States)

Smith, Gerard P

2008-11-01

Cannon's theory of homeostasis is the first, major, American contribution to physiological thought. Although it is clear that Cannon's account of homeostasis is personal and based primarily on the work of his laboratory, Cannon made it easy for readers to mistake his 1929 paper and 1932 book for a comprehensive review of the literature relevant to homeostasis. This is unfortunate because Cannon never acknowledged the important contributions of two of his contemporaries, Ivan Pavlov and Joseph Barcroft. Since he did not mention them, their contributions are rarely discussed. This paper attempts to correct this historical problem in two ways. First, I describe the unacknowledged contributions of Pavlov and Barcroft. Then I consider the possible reasons why Cannon ignored them.

The Kepler Dichotomy in Planetary Disks: Linking Kepler Observables to Simulations of Late-stage Planet Formation

Science.gov (United States)

Moriarty, John; Ballard, Sarah

2016-11-01

NASA’s Kepler Mission uncovered a wealth of planetary systems, many with planets on short-period orbits. These short-period systems reside around 50% of Sun-like stars and are similarly prevalent around M dwarfs. Their formation and subsequent evolution is the subject of active debate. In this paper, we simulate late-stage, in situ planet formation across a grid of planetesimal disks with varying surface density profiles and total mass. We compare simulation results with observable characteristics of the Kepler sample. We identify mixture models with different primordial planetesimal disk properties that self-consistently recover the multiplicity, radius, period and period ratio, and duration ratio distributions of the Kepler planets. We draw three main conclusions. (1) We favor a “frozen-in” narrative for systems of short-period planets, in which they are stable over long timescales, as opposed to metastable. (2) The “Kepler dichotomy,” an observed phenomenon of the Kepler sample wherein the architectures of planetary systems appear to either vary significantly or have multiple modes, can naturally be explained by formation within planetesimal disks with varying surface density profiles. Finally, (3) we quantify the nature of the “Kepler dichotomy” for both GK stars and M dwarfs, and find that it varies with stellar type. While the mode of planet formation that accounts for high multiplicity systems occurs in 24% ± 7% of planetary systems orbiting GK stars, it occurs in 63% ± 16% of planetary systems orbiting M dwarfs.

Mathematical foundation of geodesy selected papers of Torben Krarup

CERN Document Server

Borre, K

2006-01-01

This volume contains selected papers by Torben Krarup, one of the most important geodesists of the 20th century. The collection includes the famous booklet "A Contribution to the Mathematical Foundation of Physical Geodesy" from 1969, the unpublished "Molodenskij letters" from 1973, the final version of "Integrated Geodesy" from 1978, "Foundation of a Theory of Elasticity for Geodetic Networks" from 1974, as well as trend-setting papers on the theory of adjustment.

The Nigerian Marine Department contribution to British colonial ...

African Journals Online (AJOL)

The paper examines the contributions of the Marine Department to the development of the colonial economy and its impact on the maritime development of ... paper finds out that the activities of the Marine Department opened up the littoral routes through the dredging of Nigeria's maritime environment for trade between the ...

Computerized Clinical Decision Support: Contributions from 2015

Science.gov (United States)

Bouaud, J.

2016-01-01

Summary Objective To summarize recent research and select the best papers published in 2015 in the field of computerized clinical decision support for the Decision Support section of the IMIA yearbook. Method A literature review was performed by searching two bibliographic databases for papers related to clinical decision support systems (CDSSs) and computerized provider order entry (CPOE) systems. The aim was to identify a list of candidate best papers from the retrieved papers that were then peer-reviewed by external reviewers. A consensus meeting between the two section editors and the IMIA editorial team was finally conducted to conclude in the best paper selection. Results Among the 974 retrieved papers, the entire review process resulted in the selection of four best papers. One paper reports on a CDSS routinely applied in pediatrics for more than 10 years, relying on adaptations of the Arden Syntax. Another paper assessed the acceptability and feasibility of an important CPOE evaluation tool in hospitals outside the US where it was developed. The third paper is a systematic, qualitative review, concerning usability flaws of medication-related alerting functions, providing an important evidence-based, methodological contribution in the domain of CDSS design and development in general. Lastly, the fourth paper describes a study quantifying the effect of a complex, continuous-care, guideline-based CDSS on the correctness and completeness of clinicians’ decisions. Conclusions While there are notable examples of routinely used decision support systems, this 2015 review on CDSSs and CPOE systems still shows that, despite methodological contributions, theoretical frameworks, and prototype developments, these technologies are not yet widely spread (at least with their full functionalities) in routine clinical practice. Further research, testing, evaluation, and training are still needed for these tools to be adopted in clinical practice and, ultimately, illustrate

[A pharmacist, creator of the first French daily paper: Cadet de Vaux].

Science.gov (United States)

Cailhol, C; Flahaut, J

1998-01-01

Cadet de Vaux, in partnership with Louis Dussieux and Olivier de Carancez, was the creator of the first French daily news paper, on the 1st of January 1877. Cadet had the responsibility of the scientific section. Several lampoons were written against the three directors of the paper. The paper was momentarily suppressed two times, because of non convenient contributions, and it was stopped his activities in the paper.

Quantum Entanglements: Selected Papers

International Nuclear Information System (INIS)

Giannetto, E

2005-01-01

This book is a sort of tribute to Rob Clifton (1964-2002), Associate Professor of Philosophy and Associate Director of the Center for Philosophy of Science at the University of Pittsburgh, philosopher of physics and editor of the journal Studies in the History and Philosophy of Modern Physics, who tragically died of cancer. It contains fourteen papers by Clifton, for the most part written in collaboration with other authors (Jeffrey Bub (2), Sheldon Goldstein, Michael Dickson, Hans Halvorson (6), Adrian Kent (2)), published between 1995 and 2002. The choice of papers made by the editors is very impressive. They concern the foundations of quantum mechanics and quantum field theory. Among the issues discussed are the modal interpretations of quantum mechanics, the problems of hidden variables theories, non-locality, Bell's inequality, the Einstein-Podolsky-Rosen paradox, Lorentz invariance, de-coherence, non-contextuality, complementarity, entanglement and quantum information. A consequence of such investigations is that non-separability is a more complex issue than violation of Bell's inequality. Apart from the perspective one can follow-whether one agrees or not with Clifton-these papers are effective contributions to an understanding of the problems involved in the foundations of quantum mechanics. The most interesting parts, in my opinion, are related to the extension of the discussion of foundational problems to quantum field theory: on the algebraic approach, and on the twin concepts of particle and vacuum. Non-locality appears to be 'worse' in relativistic quantum field theory than in non-relativistic quantum mechanics. All the papers deal with relevant epistemological and even historical aspects of quantum mechanics interpretations, but all the issues are discussed from a technical, logical and mathematical approach. A complete bibliography of Clifton's papers is given at the end of the volume. (book review)

MIGRATION OF PLANETS EMBEDDED IN A CIRCUMSTELLAR DISK

International Nuclear Information System (INIS)

Bromley, Benjamin C.; Kenyon, Scott J.

2011-01-01

Planetary migration poses a serious challenge to theories of planet formation. In gaseous and planetesimal disks, migration can remove planets as quickly as they form. To explore migration in a planetesimal disk, we combine analytic and numerical approaches. After deriving general analytic migration rates for isolated planets, we use N-body simulations to confirm these results for fast and slow migration modes. Migration rates scale as m -1 (for massive planets) and (1 + (e H /3) 3 ) -1 , where m is the mass of a planet and e H is the eccentricity of the background planetesimals in Hill units. When multiple planets stir the disk, our simulations yield the new result that large-scale migration ceases. Thus, growing planets do not migrate through planetesimal disks. To extend these results to migration in gaseous disks, we compare physical interactions and rates. Although migration through a gaseous disk is an important issue for the formation of gas giants, we conclude that migration has little impact on the formation of terrestrial planets.

Mixing time study to select suitable stirrer for electrorefiner. Contributed Paper RD-03

International Nuclear Information System (INIS)

Agarwal, Sourabh; Mythili, M; Joseph, Joby; Nandakumar, V.; Muralidharan, B.; Padmakumar, G.; Rajan, K.K.

2014-01-01

Pyro-processing is an alternative to conventional methods of aqueous reprocessing of nuclear fuels. Electrorefining is an important process step in pyro-processing, carried out in a high temperature molten salt bath in an Electrorefiner. The recovery of actinides from the spent fuels has to be high. One of the methods to achieve this is to ensure proper mixing of the molten salt in the electrorefiner. The optimum design of the stirrer should ensure efficient mixing with minimum mixing time. Studies have been carried out in an engineering scale model of the electrorefiner to study the mixing phenomena. This paper brings outs the series of experiments conducted on an ambient temperature electrorefiner to select a suitable stirrer. (author)

Scientific papers for health informatics.

Science.gov (United States)

Pereira, Samáris Ramiro; Duarte, Jacy Marcondes; Bandiera-Paiva, Paulo

2013-01-01

From the hypothesis that the development of scientific papers, mainly in interdisciplinary areas such as Health Informatics, may bring difficulties to the author, as had its communicative efficacy decreased or compromising their approval for publication; we aim to make considerations on the main items to good players making this kind of text. The scientific writing has peculiarities that must be taken into consideration when it writes: general characteristics, such as simplicity and objectivity, and characteristics of each area of knowledge, such as terminology, formatting and standardization. The research methodology adopted is bibliographical. The information was based on literature review and the authors' experience, teachers and assessors of scientific methodology in peer review publications in the area. As a result, we designed a checklist of items to be checked before submission of a paper to a scientific publication vehicle in order to contribute to the promotion of research, facilitating the publication and increase its capacity in this important area of knowledge.

Solar System Evolution through Planetesmial Collisions

Science.gov (United States)

Trierweiler, Isabella; Laughlin, Greg

2018-01-01

Understanding planet formation is crucial to unraveling the history of our Solar System. Refining our theory of planet formation has become particularly important as the discovery of exoplanet systems through missions like Kepler have indicated that our system is incredibly unique. Compared to other systems around Sun-like stars, we are missing a significant amount of mass in the inner region of our solar system.A leading explanation for the low mass of the terrestrial planets is Jupiter’s Grand Tack. In this theory, the existence of the rocky planets is thought to be the result of the migration of Jupiter through the inner solar system. This migration could spark a collisional cascade of planetesimals, allowing planetesimals to drift inwards and shepherd an original set of massive planets into the Sun, thus explaining the absence of massive planets in our current system. The remnants of the planetesimals would them become the building blocks for a new generation of smaller, rocky planets.Using the N-body simulator REBOUND, we investigate the dynamics of the Grand Tack. We focus in particular on collisional cascades, which are thought to cause the inward planetesimal drift. We first modify the simulator to account for fragmentation outcomes in planetesimal collisions. Modeling disks of varying initial conditions, we then characterize the disk conditions needed to begin a cascade and shed light on the solar system’s dynamics just prior to the formation of the terrestrial planets.

Paper use in research ethics applications and study conduct.

Science.gov (United States)

Chakladar, Abhijoy; Eckstein, Sue; White, Stuart M

2011-02-01

Application for Research Ethics Committee (REC) approval and the conduct of medical research is paper intensive. This retrospective study examined all applications to a single REC in the south of England over one year. It estimated the mass of paper used, comparing the proportional paper consumption of different trial types and during different stages of the research process, quantifying the consumption in terms of carbon dioxide emissions. In 2009, 68 trials were submitted to the REC. Total paper consumption for the REC process and study conduct was 176,150 sheets of A4 paper (879 kg), equivalent to an estimated 11.5 million sheets (88 tonnes, 2100 trees) a year for the U.K.; the REC process accounted for 26.4%. REC applications and the conduct of approved trials generate considerable environmental impact through paper consumption contributing to the NHS's carbon footprint. Paper use might be reduced through the implementation of digital technologies and revised research methods, namely changing attitudes in both researchers and ethics committees.

Characterizing bacterial communities in paper production-troublemakers revealed.

Science.gov (United States)

Zumsteg, Anita; Urwyler, Simon K; Glaubitz, Joachim

2017-08-01

Biofilm formation is a major cause of reduced paper quality and increased down time during paper manufacturing. This study uses Illumina next-generation sequencing to identify the microbial populations causing quality issues due to their presence in biofilms and slimes. The paper defects investigated contained traces of the films and/or slime of mainly two genera, Tepidimonas and Chryseobacterium. The Tepidimonas spp. found contributed on average 68% to the total bacterial population. Both genera have been described previously to be associated with biofilms in paper mills. There was indication that Tepidimonas spp. were present as compact biofilm in the head box of one paper machine and was filtered out by the paper web during production. On the other hand Tepidimonas spp. were also present to a large extent in the press and white waters of two nonproblematic paper machines. Therefore, the mere presence of a known biofilm producer alone is not sufficient to cause slimes and therefore paper defects and other critical factors are additionally at play. For instance, we identified Acidovorax sp., which is an early colonizer of paper machines, exhibiting the ability to form extracellular DNA matrices for attachment and biofilm formation. © 2017 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

Optimization of the Actuarial Model of Defined Contribution Pension Plan

Directory of Open Access Journals (Sweden)

Yan Li

2014-01-01

Full Text Available The paper focuses on the actuarial models of defined contribution pension plan. Through assumptions and calculations, the expected replacement ratios of three different defined contribution pension plans are compared. Specially, more significant considerable factors are put forward in the further cost and risk analyses. In order to get an assessment of current status, the paper finds a relationship between the replacement ratio and the pension investment rate using econometrics method. Based on an appropriate investment rate of 6%, an expected replacement ratio of 20% is reached.

Book of abstracts. Invited and contributed papers

International Nuclear Information System (INIS)

1995-01-01

The book is a collection of abstracts submitted to the International Nuclear Physics Conference held on August 21-26, 1995 in Beijing, China. The conference is organized by China Institute of Atomic Energy. The main topics of the conference are: relativistic nuclear collisions, mesons and baryons in nuclei, hadron structure and quarks in nuclei, formation and properties of hot nuclei, nuclear reactions at low and intermediate energies, nuclear structure, radioactive nuclear beams, nuclear astrophysics, fundamental interaction and symmetries, applied nuclear physics

CONTRIBUTIONS OF HISTORICAL CRITICAL PEDAGOGY TO GEOGRAPHY TEACHING

Directory of Open Access Journals (Sweden)

Lucas André Teixeira

2015-06-01

Full Text Available This paper aims to show some contributions of historical critical pedagogy to Geography teaching. Such thoughts aim to discuss how this teaching enters school education in the context of neoliberalism. Assuming that the emptiness in Geography teaching in school education is a result of Brazilian educational policies in neoliberalism, we intend to characterize the impairment of the critical perspective on this area of knowledge and present some contributions of historical critical pedagogy to face and overcome the current order. Besides, we seek to highlight the required knowledge to achieve an education that contributes to build a different society.

CALL FOR PAPERS: Special issue on Symmetries and Integrability of Difference Equations

Science.gov (United States)

Doliwa, Adam; Korhonen, Risto; Lafortune, Stephane

2006-10-01

This is a call for contributions to a special issue of Journal of Physics A: Mathematical and General entitled `Special issue on Symmetries and Integrability of Difference Equations' as featured at the SIDE VII meeting held during July 2006 in Melbourne (http://web.maths.unsw.edu.au/%7Eschief/side/side.html). Participants at that meeting, as well as other researchers working in the field of difference equations and discrete systems, are invited to submit a research paper to this issue. This meeting was the seventh of a series of biennial meetings devoted to the study of integrable difference equations and related topics. The notion of integrability was first introduced in the 19th century in the context of classical mechanics with the definition of Liouville integrability for Hamiltonian flows. Since then, several notions of integrability have been introduced for partial and ordinary differential equations. Closely related to integrability theory is the symmetry analysis of nonlinear evolution equations. Symmetry analysis takes advantage of the Lie group structure of a given equation to study its properties. Together, integrability theory and symmetry analysis provide the main method by which nonlinear evolution equations can be solved explicitly. Difference equations, just as differential equations, are important in numerous fields of science and have a wide variety of applications in such areas as: mathematical physics, computer visualization, numerical analysis, mathematical biology, economics, combinatorics, quantum field theory, etc. It is thus crucial to develop tools to study and solve difference equations. While the theory of symmetry and integrability for differential equations is now well-established, this is not yet the case for discrete equations. The situation has undergone impressive development in recent years and has affected a broad range of fields, including the theory of special functions, quantum integrable systems, numerical analysis, cellular

DEDUCTIBILITY OF CONTRIBUTIONS TO VOLUNTARY PRIVATE PENSIONS

Directory of Open Access Journals (Sweden)

LILIANA MUNTEAN

2011-01-01

Full Text Available The present paper approaches the notion of public and private pension in Romania. Pension can be seen in terms of a replacement income to individuals whose age no longer affords to operate in the labour market. Pension reform in Romania has allowed besides the public pension system, called Pillar I, which is a distributive system based on solidarity between generations also a private pension system that records the contributions of participants in individual accounts, based on capitalization, investment and accumulation of these contributions.

Doing more with less. green paper on energy efficiency

International Nuclear Information System (INIS)

2005-01-01

Even without high and volatile oil prices, which have led to a downgrading of the prospects of economic growth in Europe, there would be very good reasons for the European Union to make a strong push towards a re-invigorated programme promoting energy efficiency at all levels of European society. This green paper seeks to act as a catalyst, leading to a renewed energy efficiency initiative at all levels of European society - EU, national, regional and local. Furthermore, this Green Paper seeks to make a significant contribution, by way of example and leadership, to kick-start an international effort to contribute to addressing climatic change through energy efficiency. China presently uses more than five times as much energy as the EU to produce one unit of GDP, USA uses approximately 50% more than EU. With exploding energy demand, in particular in China and India, energy efficiency must be one of the key policies to try to reconcile, on the one hand, the increased energy needs of the developing world to power growth and improve living conditions and, on the other hand, combat global warming. This Green Paper, and the momentum created in following it up, should put the EU at the forefront of efforts to make energy efficiency a global priority. (BA)

Recovery of uranium from uranyl nitrate raffinate. Contributed Paper PE-06

International Nuclear Information System (INIS)

Anilkumar Reddy, A.M.; Shiva Kumar, M.; Varadan, K.M.K.; Babaji, P.; Sairam, S. Sheela; Saibaba, N.

2014-01-01

At New Uranium Oxide Fuel Plant, NUOFP(O) of Nuclear Fuel Complex (NFC), the Uranyl Nitrate Raffinate (UNR) generated during solvent extraction process is washed with Treated Lean Solvent(TLS) to recover residual U. Earlier this UNR consisting of 0.5-1 gm/l and 2.5 FA was neutralised with vapour ammonia. The slurry was then filtered over pre coat drum filter and the resultant Uranyl Nitrate Raffinate cake (UNRC) was stored in polyethylene lined MS drums. The valuable U was thus being locked up in UNRC. Also, the storage of UNRC drums required lot of floor space which have to be repacked frequently to contain the radioactivity. Hence the need has come to avoid the generation of UNRC and the recovery of U from the already generated UNRC. The generation of UNRC was avoided by developing alternate process of UNR treatment with Treated Lean Solvent for the removal of residual U and the resulting Acidic Raffinate Slurry (ARS) is disposed. The Uranium recovery from UNRC is done by dissolving the cake in Uranyl Nitrate Raffinate solution to leach the hexavalent Uranium by utilizing the free acidity in UNR. The leaching time is about six hours and the uranium forms uranyl nitrate. The resulting leach solutions are relatively dilute but complex acidic nitrate solutions containing wide variety of ions. Metallic ions commonly present include uranium, iron, magnesium, aluminium, sodium, calcium etc. The uranium concentration is normally 1-1.5 g/L. This uranium is separated by solvent extraction. The active agent in solvent extraction is Tri Butyl Phosphate in kerosene that can selectively extract uranium into an organic complex which is insoluble in aqueous. The organic used for extraction is Treated Lean Solvent in the quality of freshly prepared solvent and the resulting Acidic Raffinate Slurry is disposed by sale. The leaching of Uranium from UNRC was done in plant scale and about 1200 kgs of UNRC was successfully processed in trial batch. The paper deals with details of

Interstellar Explorer Observations of the Solar System's Debris Disks

Science.gov (United States)

Lisse, C. M.; McNutt, R. L., Jr.; Brandt, P. C.

2017-12-01

Planetesimal belts and debris disks full of dust are known as the "signposts of planet formation" in exosystems. The overall brightness of a disk provides information on the amount of sourcing planetesimal material, while asymmetries in the shape of the disk can be used to search for perturbing planets. The solar system is known to house two such belts, the Asteroid belt and the Kuiper Belt; and at least one debris cloud, the Zodiacal Cloud, sourced by planetisimal collisions and Kuiper Belt comet evaporative sublimation. However these are poorly understood in toto because we live inside of them. E.g., while we know of the two planetesimal belt systems, it is not clear how much, if any, dust is produced from the Kuiper belt since the near-Sun comet contributions dominate near-Earth space. Understanding how much dust is produced in the Kuiper belt would give us a much better idea of the total number of bodies in the belt, especially the smallest ones, and their dynamical collisional state. Even for the close in Zodiacal cloud, questions remain concerning its overall shape and orientation with respect to the ecliptic and invariable planes of the solar system - they aren't explainable from the perturbations caused by the known planets alone. In this paper we explore the possibilities of using an Interstellar Explorer telescope placed at 200 AU from the sun to observe the brightness, shape, and extent of the solar system's debris disk(s). We should be able to measure the entire extent of the inner, near-earth zodiacal cloud; whether it connects smoothly into an outer cloud, or if there is a second outer cloud sourced by the Kuiper belt and isolated by the outer planets, as predicted by Stark & Kuchner (2009, 2010) and Poppe et al. (2012, 2016; Figure 1). VISNIR imagery will inform about the dust cloud's density, while MIR cameras will provide thermal imaging photometry related to the cloud's dust particle size and composition. Observing at high phase angle by looking

Defined Contribution Pension Plans: Mutual Fund Asset Allocation Changes

OpenAIRE

Clemens Sialm; Laura Starks; Hanjiang Zhang

2015-01-01

In this paper we compare changes in asset allocations between mutual funds held in defined contribution pension plans and funds held by other investors. We investigate how flows into equity and fixed income mutual funds depend on macroeconomic conditions. We find that defined contribution plans react more sensitively to these conditions, suggesting effects on mutual fund managers and other investors.

Contribution of "Women's Gold" to West African livelihoods

DEFF Research Database (Denmark)

Pouliot, Mariéve

2012-01-01

Contribution of ``Women's Gold'' to West African Livelihoods: The Case of Shea ( Vitellaria paradoxa ) in Burkina Faso. This paper (i) quantifies the contribution that Vitellaria paradoxa makes to the total income of rural households belonging to different economic groups in two areas of Burkina ...... not be considered as a remedy to poverty but instead as a way for households to diversify their livelihood strategy and decrease their vulnerability to food insecurity and climate variability....

An analysis of tourism contribution to economic growth in SADC ...

African Journals Online (AJOL)

The study how the tourism sector can be an engine of economic growth in SADC member countries. The paper found the contribution of tourism to GDP, employment, export receipts and investment is significant. Although this sector's contribution to the economy varies among SADC countries, the the study found that ...

Contributions to Analytic Number Theory | Lucht | Quaestiones ...

African Journals Online (AJOL)

This paper reports on some recent contributions to the theory of multiplicative arithmetic semigroups, which have been initiated by John Knopfmacher's work on analytic number theory. They concern weighted inversion theorems of the. Wiener type, mean-value theorems for multiplicative functions, and, Ramanujan

Internet and Its Contributions to Library Services

Directory of Open Access Journals (Sweden)

Yaşar Çelik

1995-06-01

Full Text Available This paper examines the major Internet services such as email, telnet and ftp and describes various information discovery and retrieval tools such as gopher, WAIS, and WWW. It also discusses the contributions of the Internet to library and information services.

ON THE EFFECT OF GIANT PLANETS ON THE SCATTERING OF PARENT BODIES OF IRON METEORITE FROM THE TERRESTRIAL PLANET REGION INTO THE ASTEROID BELT: A CONCEPT STUDY

International Nuclear Information System (INIS)

Haghighipour, Nader; Scott, Edward R. D.

2012-01-01

In their model for the origin of the parent bodies of iron meteorites, Bottke et al. proposed differentiated planetesimals, formed in 1-2 AU during the first 1.5 Myr, as the parent bodies, and suggested that these objects and their fragments were scattered into the asteroid belt as a result of interactions with planetary embryos. Although viable, this model does not include the effect of a giant planet that might have existed or been growing in the outer regions. We present the results of a concept study where we have examined the effect of a planetary body in the orbit of Jupiter on the early scattering of planetesimals from the terrestrial region into the asteroid belt. We integrated the orbits of a large battery of planetesimals in a disk of planetary embryos and studied their evolutions for different values of the mass of the planet. Results indicate that when the mass of the planet is smaller than 10 M ⊕ , its effects on the interactions among planetesimals and planetary embryos are negligible. However, when the planet mass is between 10 and 50 M ⊕ , simulations point to a transitional regime with ∼50 M ⊕ being the value for which the perturbing effect of the planet can no longer be ignored. Simulations also show that further increase of the mass of the planet strongly reduces the efficiency of the scattering of planetesimals from the terrestrial planet region into the asteroid belt. We present the results of our simulations and discuss their possible implications for the time of giant planet formation.

The value contribution of strategic foresight

DEFF Research Database (Denmark)

Rohrbeck, René; Schwarz, Jan Oliver

2013-01-01

This paper focuses on exploring the potential and empirically observable value creation of strategic foresight activities in firms. We first review the literature on strategic foresight, innovation management and strategic management in order to identify the potential value contributions. We use ......, (3) influencing other actors, (4) and through an enhanced capacity for organizational learning....

U.S. contributions to ITER

International Nuclear Information System (INIS)

Sauthoff, Ned R.

2006-01-01

The United States participates in the ITER project to undertake the study of the science and technology of burning plasmas. The 2003 U.S. decision to enter the ITER negotiations followed an extensive series of community and governmental reviews of the benefits, readiness, and approaches to the study of burning plasmas. This paper describes both the technical and the organizational preparations and plans for U.S. participation in the ITER construction activity: in-kind contributions, staff contributions, and cash contributions as well as supporting physics and technology research. Near-term technical activities focus on the completion of R and D and design and mitigation of risks in the areas of provisionally assigned US contributions. Outside the project, the U.S. is engaged in preparations for the test blanket module program. Organizational activities focus on preparations of the project management arrangements to maximize the overall success of the ITER project: elements include refinement of U.S. positions on the international arrangements, the establishment of the U.S. Domestic Agency, progress along the path of the U.S. Department of Energy's Project Management Order, and overall preparations for commencement of the fabrication of major items of equipment and for provision of staff and cash as specified in the upcoming ITER agreement

Contributions to thermal and fluid dynamic problems in nuclear technology

International Nuclear Information System (INIS)

Mueller, U.; Krebs, L.; Rust, K.

1984-02-01

The majority of contributions compiled in this report deals with thermal and fluid dynamic problems in nuclear engineering. Especially problems of heat transfer and cooling are represented which may arise during and afer a loss-of-coolant accident both in light water reactors and in liquid metal cooled fast breeder reactors. Papers on the mass transfer in pressurized water, tribological problems in sodium cooled reactors, the fluid dynamics of pulsed column, and fundamental investigations of convective flows supplement these contributions on problems connected with accidents. Furthermore, a keynote paper presents the individual activities relating to the reliability of reactor components, a field recently included in our research program. Technical solutions to special problems are closely connected to the investigations based on experiments. Therefore, several contributions deal with new developments in technology and measuring techniques. (orig.) [de

Assessment factors for human health risk assessment: a discussion paper

NARCIS (Netherlands)

Vermeire TG; Stevenson H; Pieters MN; Rennen M; Slob W; Hakkert BC; Nederlandse organisatie voor; CSR; LEO; TNO-ITV

1998-01-01

The general goal of this discussion paper is to contribute towards further harmonisation of the human health risk assessment. It discusses the development of a formal, harmonised set of default assessment factors. The status quo with regard to assessment factors is reviewed. Options are presented

A magma ocean and the Earth's internal water budget

Science.gov (United States)

Ahrens, Thomas J.

1992-01-01

There are lines of evidence which relate bounds on the primordial water content of the Earth's mantle to a magma ocean and the accompanying Earth accretion process. We assume initially (before a magma ocean could form) that as the Earth accreted, it grew from volatile- (H2O, CO2, NH3, CH4, SO2, plus noble) gas-rich planetesimals, which accreted to form an initial 'primitive accretion core' (PAC). The PAC retained the initial complement of planetesimal gaseous components. Shock wave experiments in which both solid, and more recently, the gaseous components of materials such as serpentine and the Murchison meteorite have demonstrated that planetesimal infall velocities of less than 0.5 km/sec, induce shock pressures of less than 0.5 GPa and result in virtually complete retention of planetary gases.

The range of validity of the two-body approximation in models of terrestrial planet accumulation. II - Gravitational cross sections and runaway accretion

Science.gov (United States)

Wetherill, G. W.; Cox, L. P.

1985-01-01

The validity of the two-body approximation in calculating encounters between planetesimals has been evaluated as a function of the ratio of unperturbed planetesimal velocity (with respect to a circular orbit) to mutual escape velocity when their surfaces are in contact (V/V-sub-e). Impact rates as a function of this ratio are calculated to within about 20 percent by numerical integration of the equations of motion. It is found that when the ratio is greater than 0.4 the two-body approximation is a good one. Consequences of reducing the ratio to less than 0.02 are examined. Factors leading to an optimal size for growth of planetesimals from a swarm of given eccentricity and placing a limit on the extent of runaway accretion are derived.

Income inequality in the EU: How do member states contribute?

NARCIS (Netherlands)

Papatheodorou, C.; Pavlopoulos, D.

2014-01-01

Purpose: The purpose of this paper is to analyse the structure of overall inequality in the EU-15 by investigating the extent to which total inequality is attributed to inequality between or within the individual countries. Also, the paper examines whether the contribution of between-country and

[An unpublished contribution of Melanie Klein "On Reassurance"].

Science.gov (United States)

Frank, Claudia; Klein, Melanie

2005-01-01

Melanie Klein's unpublished paper on reassurance is presented in German translation. The author shows that it was a contribution to Glover's investigation on psychoanalytic technique in the 1930s. The paper is discussed against the background of the technical discussions conducted in London at that time (e. g. M. Schmideberg, J. Strachey) and of Klein's relevant publications. Although Klein consistently considered "correct" interpretation to be the most effective means of reassurance, she occasionally also accepted a non-interpreting approach. In this respect the paper presented here goes further than any other of her writings.

On Academician Behounek's paper ''Lung cancer induced by ionizing radiation''

International Nuclear Information System (INIS)

Thomas, J.

1979-01-01

The significance and scientific contribution are discussed of the paper ''Lung Cancer Induced by Ionizing Radiation'' submitted by Academician Frantisek Behounek to the nation-wide workshop of the Czechoslovak Society of Pneumology and Oncology in Prague, October 3 and 4, 1952 and published in the Proceedings in 1953. The paper discussed the problem which still remains topical, ie., lung exposure to radon daughters, which Academician Behounek considered to be the true cause of lung cancer in Jachymov miners. (B.S.)

Contribution of Latin America to pharmacovigilance.

Science.gov (United States)

González, Juan Camilo; Arango, Victoria E; Einarson, Thomas R

2006-01-01

Pharmacovigilance activities have been ongoing for 4 decades. However, little is known (especially outside of the area) about the contribution of Latin America to this field. To review and quantify the published literature on pharmacovigilance in Latin American countries. We searched electronic databases including MEDLINE (1966-2004), EMBASE (1980-2004), International Pharmaceutical Abstracts (1970-2004), Toxline (1992-2004), Literatura Latino-Americana e do Caribe em Ciências da Saúde (1982-2004), Sistema de Información Esencial en Terapéutica y Salud (1980-2004), and the Pan American Health Organization Web site (1970-2004) for articles on pharmacovigilance or adverse drug reactions in any of the 19 major Latin American countries. Papers were retrieved and categorized according to content and country of origin by 2 independent reviewers. There were 195 usable articles from 13 countries. Fifty-one of the papers retrieved dealt with pharmacovigilance centers (15 national centers, 10 hospitals, 26 other), 55 covered pharmacovigilance itself (21 theoretical papers, 9 with description of models, 25 educational papers), and 89 were pharmacoepidemiologic studies of adverse drug reactions (69 case reports, 13 observational cohorts, 2 cohort studies, 1 randomized clinical trial, 4 clinical papers on adverse reaction management). Studies have increased exponentially since 1980. Five countries (Argentina, Brazil, Chile, Costa Rica, Venezuela) published reports from national centers. No studies were found from 6 countries: Dominican Republic, El Salvador, Honduras, Nicaragua, Paraguay, or Uruguay. Most studied categories were antiinfectives and drugs affecting the central nervous system, cardiovascular system, and musculoskeletal system. Contributions of Latin American countries to the field of pharmacovigilence have been remarkable, considering the constraints on these countries. A need exists for an increased number of formal pharmacovigilance studies and research

Recent contributions to fusion reactor design and technology development

International Nuclear Information System (INIS)

1979-11-01

The report contains a collection of 16 recent fusion technology papers on the STARFIRE Project, the study of alternate fusion fuel cycles, a maintainability study, magnet safety, neutral beam power supplies and pulsed superconducting magnets and energy transfer. This collection of papers contains contributions for Argonne National Laboratory, McDonnell Douglas Astronautics Company, General Atomic Company, The Ralph M. Parsons Company, the University of Illinois, and the University of Wisconsin. Separate abstracts are presented for each paper

COMPETITIVENESS OF THE PORT OF SINES: THE RBV CONTRIBUTION

OpenAIRE

Azevedo, Susana; Ferreira, João

2008-01-01

The main objective of this paper is to analyze the competitiveness of the main maritime Port sited in Portugal - Port of Sines. This paper is developed under the Resource-based view approach. A literature review about the Resource-based view is presented with a special highlight on the contribution of organizations owns’ resources to the competitiveness. With this paper we intend to emphasize the applicability of a management theory to a different type of organizations which only recently st...

Moving from payg pensions to defined-contribution plan in the Russian Federation

Directory of Open Access Journals (Sweden)

Arnautova Yulia Valerievna

2016-03-01

Full Text Available This article is devoted to the moving from PAYG Pensions to Defined-Contribution Plan. The special aspects of this reorganization are analyzed. Pen-sion models of OECD countries are compared. Inability of the Defined-Contribution Plan in Russia is being proved. The present paper provides modern ways to improve the Defined-Contribution pension schemes.

Gauss’s, Cholesky’s and Banachiewicz’s Contributions to Least Squares

DEFF Research Database (Denmark)

Gustavson, Fred G.; Wasniewski, Jerzy

This paper describes historically Gauss’s contributions to the area of Least Squares. Also mentioned are Cholesky’s and Banachiewicz’s contributions to linear algebra. The material given is backup information to a Tutorial given at PPAM 2011 to honor Cholesky on the hundred anniversary of his...

Assessment factors for human health risk assessment: A discussion paper

NARCIS (Netherlands)

Vermeire, T.; Stevenson, H.; Pieters, M.N.; Rennen, M.; Slob, W.; Hakkert, B.C.

1999-01-01

The general goal of this discussion paper is to contribute toward the further harmonization of human health risk assessment. It first discusses the development of a formal, harmonized set of assessment factors. The status quo with regard to assessment factors is reviewed, that is, the type of

Contribution Index Based on Green Building Certification Systems

Directory of Open Access Journals (Sweden)

Yuting Sun

2015-05-01

Full Text Available Green Building Certification Systems (GBCS are carried out in many countries due to the rising awareness of the importance of sustainability in the building industry. The intention should have motivated participants to construct and operate buildings sustainably, however, there is not yet a method developed to investigate the motivation of the participants. Based on the GBCS, this paper proposes the contribution index as a standard global method to analyze the performance of participants in the green building industry. Three contribution indices, namely Frequency Contribution Index (FCI, Intensity Contribution Index (ICI and Comprehensive Contribution Index (CCI that concern each different category of participant, have been formulated. Three further analyses based on the index were undertaken to investigate some features of the industry. A case study of Singapore was conducted to show how the contribution index could be used to extract industry patterns and trends and assess the participants’ performance in the green building industry. Interviews with experts provide some suggested applications and support for the findings.

Healthcare Engineering Defined: A White Paper.

Science.gov (United States)

Chyu, Ming-Chien; Austin, Tony; Calisir, Fethi; Chanjaplammootil, Samuel; Davis, Mark J; Favela, Jesus; Gan, Heng; Gefen, Amit; Haddas, Ram; Hahn-Goldberg, Shoshana; Hornero, Roberto; Huang, Yu-Li; Jensen, Øystein; Jiang, Zhongwei; Katsanis, J S; Lee, Jeong-A; Lewis, Gladius; Lovell, Nigel H; Luebbers, Heinz-Theo; Morales, George G; Matis, Timothy; Matthews, Judith T; Mazur, Lukasz; Ng, Eddie Yin-Kwee; Oommen, K J; Ormand, Kevin; Rohde, Tarald; Sánchez-Morillo, Daniel; Sanz-Calcedo, Justo García; Sawan, Mohamad; Shen, Chwan-Li; Shieh, Jiann-Shing; Su, Chao-Ton; Sun, Lilly; Sun, Mingui; Sun, Yi; Tewolde, Senay N; Williams, Eric A; Yan, Chongjun; Zhang, Jiajie; Zhang, Yuan-Ting

2015-01-01

Engineering has been playing an important role in serving and advancing healthcare. The term "Healthcare Engineering" has been used by professional societies, universities, scientific authors, and the healthcare industry for decades. However, the definition of "Healthcare Engineering" remains ambiguous. The purpose of this position paper is to present a definition of Healthcare Engineering as an academic discipline, an area of research, a field of specialty, and a profession. Healthcare Engineering is defined in terms of what it is, who performs it, where it is performed, and how it is performed, including its purpose, scope, topics, synergy, education/training, contributions, and prospects.

DETERMINANTS OF CASH WAQF CONTRIBUTION IN KLANG VALLEY AND SELANGOR: A SEM APPROACH

Directory of Open Access Journals (Sweden)

Muhammad Rizky Prima Sakti

2016-08-01

Full Text Available Cash waqf is becoming one of the popular Islamic financial instruments which not only focus on the religiosity but also has significant impact to the ummah development. This waqf scheme does not require richness in wealth, yet everybody in the society can contribute to cash waqf. The importance of cash waqf is getting popular as it has benefited in many ways, for example it can be used to develop assets and abandoned land for business and agricultural purposes. In addition, cash waqf also can be utilized to help institutions who are facing financial problem or liquidity issues. Nonetheless, rarely we found in the literature that empirically examines the cash waqf determinants and contributions. This paper is one of the few empirical studies that investigate the determinants towards the contribution of cash waqf in Malaysia. The purpose of this paper is to investigate the main factors that influence people towards the contribution of cash waqf instruments, special reference to the Klang Valley and Selangor. This paper employs structural equation modeling (SEM to verify the determinants of cash waqf contribution. In doing so, we use primary data by distributing self-administrated questionnaire constituting a sample of 114 respondents from Klang Valley and Selangor. Our empirical results reveal that the main factors that driven people towards the contribution of cash waqf products are attitude and social influences, however interestingly religion obligation is not influence the contribution of cash waqf.

Counting Highly Cited Papers for University Research Assessment: Conceptual and Technical Issues

Science.gov (United States)

Rodríguez-Navarro, Alonso

2012-01-01

A Kuhnian approach to research assessment requires us to consider that the important scientific breakthroughs that drive scientific progress are infrequent and that the progress of science does not depend on normal research. Consequently, indicators of research performance based on the total number of papers do not accurately measure scientific progress. Similarly, those universities with the best reputations in terms of scientific progress differ widely from other universities in terms of the scale of investments made in research and in the higher concentrations of outstanding scientists present, but less so in terms of the total number of papers or citations. This study argues that indicators for the 1% high-citation tail of the citation distribution reveal the contribution of universities to the progress of science and provide quantifiable justification for the large investments in research made by elite research universities. In this tail, which follows a power low, the number of the less frequent and highly cited important breakthroughs can be predicted from the frequencies of papers in the upper part of the tail. This study quantifies the false impression of excellence produced by multinational papers, and by other types of papers that do not contribute to the progress of science. Many of these papers are concentrated in and dominate lists of highly cited papers, especially in lower-ranked universities. The h-index obscures the differences between higher- and lower-ranked universities because the proportion of h-core papers in the 1% high-citation tail is not proportional to the value of the h-index. PMID:23071759

40 CFR 247.10 - Paper and paper products.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Paper and paper products. 247.10... COMPREHENSIVE PROCUREMENT GUIDELINE FOR PRODUCTS CONTAINING RECOVERED MATERIALS Item Designations § 247.10 Paper and paper products. Paper and paper products, excluding building and construction paper grades. ...

The 100 most-cited papers in general thoracic surgery: A bibliography analysis.

Science.gov (United States)

Ding, Hongdou; Song, Xiao; Chen, Linsong; Zheng, Xinlin; Jiang, Gening

2018-05-01

The status of citations can reflect the impact of a paper and its contribution to surgical practice. The aim of our study was to identify and review the 100 most-cited papers in general thoracic surgery. Relevant papers on general thoracic surgery were searched through Thomson Reuters Web of Science in the last week of November 2017. Results were returned in descending order of total citations. Their titles and abstracts were reviewed to identify whether they met our inclusion criteria by two thoracic surgeons independently. Characteristics of the first 100 papers, including title, journal name, country, first author, year of publication, total citations, citations in latest 5 years and average citation per year (ACY) were extracted and analyzed. Of the 100 papers, the mean number of citations was 322 with a range from 184 to 921. 19 journals published the papers from 1956 to 2012. Annals of Surgery had the largest number (29), followed by Journal of Thoracic and Cardiovascular Surgery (22) and Annals of Thoracic Surgery (21). The majority of the papers were published in 2000s (48) and originated from United States of America (62). There were 65 retrospective studies, 13 RCTs and 11 prospective studies. Orringer MB and Grillo HC contributed 4 first-author articles respectively. There were 53 papers on esophagus, 36 on lung, 6 on pleura and 5 on trachea. Our study identified the most-cited papers in the past several decades and offered insights into the development and advances of general thoracic surgery. It can help us understand the evidential basis of clinical decision-making today in the area. Copyright © 2018. Published by Elsevier Ltd.

Modeling collisions in circumstellar debris disks

Science.gov (United States)

Nesvold, Erika

2015-10-01

resonances near the chaotic zone. I investigate the effects of the initial eccentricity distribution of the disk particles and find a negligible effect on the gap size at Jovian planet masses, since collisions tend to erase memory of the initial particle eccentricity distributions. I also find that the presence of Trojan analogs is a potentially powerful diagnostic of planets in the mass range ˜1--10MJup. I apply my model to place new upper limits on planets around Fomalhaut, HR 4796 A, HD 202628, HD 181327, and beta Pictoris. Finally, to show how SMACK can be used to analyze a single debris disk in detail, I present a new model of the beta Pictoris disk and planet system that, for the first time, combines simulations of the colliding planetesimals and the dynamics of the dust grains, allowing me to model features and asymmetries in both submillimeter and scattered light images of the disk. I combine a 100,000 superparticle SMACK simulation with N-body integrations of the dust produced by the simulated collisions. I find that secular perturbations of the planet's measured inclination and eccentricity can explain the observed warp and planetesimal ring, while collisions between planetesimals shape the disk by eroding close-in material. The complex 3D structure of the disk due to the perturbations from the planet creates an azimuthally asymmetric spatial distribution of collisions, which could contribute to the observed azimuthal clump of CO gas seen with ALMA. My simulations of the small dust grains produced by collisions demonstrate that the "birth ring" approximation for beta Pictoris fails to account for the ˜54% of dust mass produced outside of the planetesimal ring. I also reproduce the gross morphology of high-resolution scattered light images of the disk, including the two-disk "x"-pattern seen in scattered light, which has not been replicated by previous dust dynamics models.

Papers

DEFF Research Database (Denmark)

Thoft-Christensen, Palle

The chapters in this Volume 7 of a series of PAPERS are based on papers published in the period 2004 - 2008 authored/co-authored by Palle Thoft-Christensen......The chapters in this Volume 7 of a series of PAPERS are based on papers published in the period 2004 - 2008 authored/co-authored by Palle Thoft-Christensen...

Computer Aided Flowsheet Design using Group Contribution Methods

DEFF Research Database (Denmark)

Bommareddy, Susilpa; Eden, Mario R.; Gani, Rafiqul

2011-01-01

In this paper, a systematic group contribution based framework is presented for synthesis of process flowsheets from a given set of input and output specifications. Analogous to the group contribution methods developed for molecular design, the framework employs process groups to represent...... information of each flowsheet to minimize the computational load and information storage. The design variables for the selected flowsheet(s) are identified through a reverse simulation approach and are used as initial estimates for rigorous simulation to verify the feasibility and performance of the design....

Nurse middle managers contributions to patient-centred care : A 'managerial work' analysis

NARCIS (Netherlands)

Lalleman, Pcb; Smid, G. A C; Dikken, Jeroen; Lagerwey, M. D.; Schuurmans, M J

2017-01-01

Nurse middle managers are in an ideal position to facilitate patient-centred care. However, their contribution is underexposed in literature due to difficulties to articulate this in practice. This paper explores how nurse middle managers contribute to patient-centred care in hospitals. A

How has severe accident analysis contributed to sizewell B and how can it continue to contribute in the future

International Nuclear Information System (INIS)

Harrison, J.R.; Western, D.J.

1987-01-01

Sizewell B is a proposed 1100 MWe PWR which is a UK development of the US SNUPPS design. The UK reference design document for the plant was first issued in 1981 and the Pre-Construction Safety Report (PCSR) was submitted to the Nuclear Installations Inspectorate (NII), the UK licensing authority, in 1982. A major public inquiry into the proposal took place between January 1983 and March 1985. This paper is concerned with the analysis of severe accidents. This means all the analysis that is concerned with those fault sequences that are outside the design basis of the plant and which may lead to severe consequences - either in terms of plant damage or release of radioactivity. This analysis comprises probabilistic assessments of the frequency of such sequences, transient analysis of the way such sequences develop and radiological release analysis. Part one of this paper examines how the severe accident analysis carried out for Sizewell B has contributed to the judgement that the design is sound and that the construction phase should proceed. The second part of the paper looks to the future and asks ''Can severe accident analysis make any further contribution during the period from licensing up until operation commences

Comments on the origin of Mercury

Science.gov (United States)

Kaula, W. M.

1976-01-01

The ratio between the mass of condensed matter in Mercury's nebular zone and the final mass of condensed matter in the planet is calculated, and the result suggests that condensed matter equal to more than 10 times the planet's mass was lost from that zone. Five hypotheses to account for this loss are considered: (1) the temperature in Mercury's zone was appreciably higher than the suggested value of 1400 K, (2) the excess was expelled by solar mass outflow, (3) the excess was dragged down by the sun during its contraction, (4) the excess was knocked out by Jupiter-perturbed planetesimals, and (5) the excess was knocked out by earth- and Venus-perturbed planetesimals. The plausibility of each hypothesis is examined, and it is concluded that only planetesimal scattering by earth and Venus appears to be ruled out

The Dynamical Imprint of Lost Protoplanets on the Trans-Neptunian Populations, and Limits on the Primordial Size Distribution of Trans-Neptunian Objects at Pluto and Larger Sizes.

Science.gov (United States)

Shannon, Andrew Brian; Dawson, Rebekah

2018-04-01

Planet formation remains a poorly understood process, in part because of our limited access to the intermediate phases of planetesimal and protoplanet growth. Today, the vast majority of the accessible remaining planetesimals and protoplanets reside within the Hot Trans-Neptunian Object population. This population has been depleted by 99% - 99.9% over the course of the Solar system's history, and as such the present day size-number distribution may be incomplete at the large size end. We show that such lost protoplanets would have left signatures in the dynamics of the present-day Trans-Neptunian Populations, and their primordial number can thus be statistically limited by considering the survival of ultra-wide binary TNOs, the Cold Classical Kuiper belt, and the resonant populations. We compare those limits to the predicted size-number distribution of various planetesimal and proto-planet growth models.

Calculating Historical Contributions To Climate Change. Discussing The 'Brazilian Proposal'

International Nuclear Information System (INIS)

Hoehne, N.; Blok, K.

2005-01-01

This paper discusses methodological issues relevant to the calculation of historical responsibility of countries for climate change ('The Brazilian Proposal'). Using a simple representation of the climate system, the paper compares contributions to climate change using different indicators: current radiative forcing, current GWP-weighted emissions, radiative forcing from increased concentrations, cumulative GWP-weighted emissions, global-average surface-air temperature increase and two new indicators: weighted concentrations (analogue to GWP-weighted emissions) and integrated temperature increase. Only the last two indicators are at the same time 'backward looking' (take into account historical emissions), 'backward discounting' (early emissions weigh less, depending on the decay in the atmosphere) and 'forward looking' (future effects of the emissions are considered) and are comparable for all gases. Cumulative GWP-weighted emissions are simple to calculate but are not 'backward discounting'. 'Radiative forcing' and 'temperature increase' are not 'forward looking'. 'Temperature increase' discounts the emissions of the last decade due to the slow response of the climate system. It therefore gives low weight to regions that have recently significantly increased emissions. Results of the five different indicators are quite similar for large groups (but possibly not for individual countries): industrialized countries contributed around 60% to today's climate change, developing countries around 40% (using the available data for fossil, industrial and forestry CO2, CH4 and N2O). The paper further argues including non-linearities of the climate system or using a simplified linear system is a political choice. The paper also notes that results of contributions to climate change need to be interpreted with care: Countries that developed early benefited economically, but have high historical emission, and countries developing at a later period can profit from developments

Ordinary Chondrites Viewed as Reassembled 'Splash Ejecta'

Science.gov (United States)

Sanders, I. S.

1995-09-01

A case has already been made favouring chondrites as re-assembled "splash ejecta" following low velocity collisions between molten planetesimals[1]. Here I briefly review this hypothesis, then develop further arguments in its support. The scenario envisaged may be summarized as follows. Planetesimals grew to radii greater than 30 km in less than 1 Ma after the formation of CAIs, and they were heated rapidly by the decay of 26Al. By 2 Ma each planetesimal had a molten interior insulated by a cool, dusty carapace. Low velocity collisions at this stage released enormous, turbulent, expanding clouds of incandescent spray mixed with dust and solid grains from the carapace. The cloud constituted a rather special, transient nebular environment; as it cooled the melt droplets became chondrules. Much of the cloud's contents re-assembled under gravity onto the surface of the hot, residual planetesimal and the accumulated debris became re-heated and metamorphosed. Collisions recurred over the few million years that relative velocities remained low and planetesimals remained molten. Thus, the cumulative debris contained many recycled and broken chondrules. This scenario is apparently reconcilable with chondrule cooling rates, the preservation of clasts of "planetary" rock in chondrites, the retention of volatiles in chondrules, the preservation of solar chemistry and more than a dozen other features. Is it reasonable to claim that 30 km radius bodies existed by 1 Ma, and were substantially molten by 2 Ma? Cameron[2] argued that CAIs were saved from drifting into the sun by their incorporation, soon after formation, into planetesimals whose mass was sufficient to hold them in orbits, decoupled from the drag of nebular gas. Wetherill's models [3] show that many bodies >100 km radius may have formed on a timescale of 10^5 years. In these terms, the proposed 30 km by 1 Ma is quite conservative. Regarding 26Al heating, the remarkably constant initial ratio of 26Al/27Al (5 x 10

Commissioning of a continuous melt densification system for plastic waste. Contributed Paper PE-05

International Nuclear Information System (INIS)

Anji Reddy, D.; Chennakeshavalu, G.; Ramesh Babu, B.; Subba Rao, V.; Coelho, G.J.M.; Rao, S.V.S.; Paul, Biplob

2014-01-01

Volume reduction of radioactive solid wastes is carried out with an aim to maximize the utilization of disposal space. Cellulosic combustible solid wastes like cotton, paper etc. are treated by incineration and the plastic wastes are volume reduced by baling. Compaction of plastic wastes gives volume reduction factors in the range of 3 to 5. With a view to achieve higher volume reduction factors, a melt-densification process was developed indigenously at CWMF for reducing the volume of plastic wastes before disposal. Based on laboratory results, a pilot plant scale batch Melt Densification Unit was designed and operated. 120 M 3 of Category-I polythene waste was melted and the Volume Reduction Factors (VRF) obtained were up to 20. To meet the future needs and increasing the throughput, a continues-feed, PLC controlled, advanced Melt Densification System was commissioned recently. (author)

Contributions of early Arab scholars to color science

Science.gov (United States)

Lakshminarayanan, Vasudevan

2017-09-01

The Islamic world made important discoveries in the field of color science during the medieval era. These included many fundamental ideas on the nature of color. Some of the first hue scales, though partial were developed by these scholars. They also showed that color was a percept and light and color were ontologically distinct. Other contributions by these scholars include descriptions of the color mixtures, color tops, color theory, etc. A few of these contributions will be discussed in this paper with particular attention to the work of Ibn al-Haytham on color.

Johannes Kepler and his contribution to Applied Mathematics

Science.gov (United States)

Pichler, Franz

The worldwide renown of Johannes Kepler is based above all on his contribution to astronomy. The 3 Kepler's Laws relating to the planets are well known and will ensure that his name is remembered by future generations. Besides his astronomical work, Kepler also made important contributions in the fields of theology, physics, phylosophy and mathematics. The actual paper discusses the advances by Kepler in the application of mathematics to the solution of "real life problems". The author made a concise account of some of the disciples by Kepler: Klug, Wieleitner, Caspar, Hammer, paying particular attention to works published by Kepler while he was living in Linz (1612-1628). The Kepler's contribution to applied mathematics is an example supremely worthy of emulation, the author concludes.

Healthcare Engineering Defined: A White Paper

Directory of Open Access Journals (Sweden)

Ming-Chien Chyu

2015-01-01

Full Text Available Engineering has been playing an important role in serving and advancing healthcare. The term “Healthcare Engineering” has been used by professional societies, universities, scientific authors, and the healthcare industry for decades. However, the definition of “Healthcare Engineering” remains ambiguous. The purpose of this position paper is to present a definition of Healthcare Engineering as an academic discipline, an area of research, a field of specialty, and a profession. Healthcare Engineering is defined in terms of what it is, who performs it, where it is performed, and how it is performed, including its purpose, scope, topics, synergy, education/training, contributions, and prospects.

1. international spring school and symposium on advances in materials science; contributed papers. Proceedings. V.2

International Nuclear Information System (INIS)

1994-03-01

The first International Conference on Advances in Materials Science was held on 15-20 March, 1994 in Cairo. The specialists discussed advances in materials science formation, development and observation. The applications of materials science technique in the field of construction material, Moessbauer measurements, physico science, corrosion and mechanical alloying were discussed at the meeting. more than 700 papers were presented in the meeting

1. international spring school and symposium on advances in materials science; contributed papers. Proceedings. V.2

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-03-01

The first International Conference on Advances in Materials Science was held on 15-20 March, 1994 in Cairo. The specialists discussed advances in materials science formation, development and observation. The applications of materials science technique in the field of construction material, Moessbauer measurements, physico science, corrosion and mechanical alloying were discussed at the meeting. more than 700 papers were presented in the meeting.

Social Gains from Female Education: A Cross-National Study. World Bank Discussion Papers 194.

Science.gov (United States)

Subbarao, K.; Raney, Laura

This paper on the social gains from female education is part of a series, prepared by the World Bank, on the benefits of improving opportunities for women. The paper suggests that expanding women's opportunities enhances their productivity and earning potential and thus contributes to better economic performance and poverty alleviation. Education…

A bibliometric analysis of the 100 most influential papers in burns.

Science.gov (United States)

Joyce, C W; Kelly, J C; Sugrue, C

2014-02-01

The importance of a published paper to a particular area is reflected in the quantity of citations obtained from peers. In burns, it is unknown which papers have been the most influential on this specialty. The purpose of our study was to identify the 100 most cited papers in burns and to analyze their characteristics. Twenty-seven journals were chosen for analysis. These included high impact factor scientific journals and journals dedicated to burns and trauma. Only twelve of these journals contributed to the 100 most cited papers in burns and we analyzed each paper individually looking at its subject matter, authorship, article type, institution, country and year of publication. Our citation analysis revealed an interesting mix of clinical and scientific papers that documents the key landmarks in burn care over the past 66 years. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

Breadwinning women: Economic contribution of married and cohabiting women to Costa Rican households

Directory of Open Access Journals (Sweden)

Camila Salazar Mayorga

2017-12-01

Full Text Available This paper analyzes the economic contribution of married and cohabiting women to the household income, in comparison to the income their partners generate, in Costa Rica.  From a perspective of gender roles, human capital theory and female labor participation, this paper examines what variables influence the probability of contribution.  Based on data by the 2014 National Household Survey, this study found that 51% percent of married or cohabiting women do not generate any income, which shows there is an unequal economic relationship in half of Costa Rican households and the males assume the breadwinning role.  Household chores and the number of children reduce the probability of economic contribution.  On the other hand, women with more years of schooling have a higher probability to contribute equally to the couple’s total income.

Paper as a platform for sensing applications and other devices: a review.

Science.gov (United States)

Mahadeva, Suresha K; Walus, Konrad; Stoeber, Boris

2015-04-29

Paper is a ubiquitous material that has various applications in day to day life. A sheet of paper is produced by pressing moist wood cellulose fibers together. Paper offers unique properties: paper allows passive liquid transport, it is compatible with many chemical and biochemical moieties, it exhibits piezoelectricity, and it is biodegradable. Hence, paper is an attractive low-cost functional material for sensing devices. In recent years, researchers in the field of science and engineering have witnessed an exponential growth in the number of research contributions that focus on the development of cost-effective and scalable fabrication methods and new applications of paper-based devices. In this review article, we highlight recent advances in the development of paper-based sensing devices in the areas of electronics, energy storage, strain sensing, microfluidic devices, and biosensing, including piezoelectric paper. Additionally, this review includes current limitations of paper-based sensing devices and points out issues that have limited the commercialization of some of the paper-based sensing devices.

Do School Lunches Contribute to Childhood Obesity?

Science.gov (United States)

Schanzenbach, Diane Whitmore

2009-01-01

This paper assesses whether school lunches contribute to childhood obesity. I employ two methods to isolate the causal impact of school lunches on obesity. First, using panel data, I ?nd that children who consume school lunches are more likely to be obese than those who brown bag their lunches even though they enter kindergarten with the same…

Worldwide energy prospects and nuclear contribution

International Nuclear Information System (INIS)

1999-04-01

With a growing up worldwide population and a better standard of living, the global energy consumption will rise. The CO 2 emissions will increase too because of todays share of fossil fuels in the energy sources. This paper analyzes the possible contribution of nuclear energy in this context: economical and environmental aspects, political aspects (distribution of energy resources, energy dependence), energy efficiency, reduction of CO 2 emissions. (J.S.)

Debris Disks: Probing Planet Formation

OpenAIRE

Wyatt, Mark C.

2018-01-01

Debris disks are the dust disks found around ~20% of nearby main sequence stars in far-IR surveys. They can be considered as descendants of protoplanetary disks or components of planetary systems, providing valuable information on circumstellar disk evolution and the outcome of planet formation. The debris disk population can be explained by the steady collisional erosion of planetesimal belts; population models constrain where (10-100au) and in what quantity (>1Mearth) planetesimals (>10km i...

Large contribution to the neutron electric dipole moment from a dimension-six four-quark operator

International Nuclear Information System (INIS)

He, X.; McKellar, B.

1993-01-01

In this paper we study the contribution of a dimension-six four-quark operator to the neutron electric dipole moment. We find that this contribution dominates over the one-loop contributions due to W L- WR mixing by at least one order of magnitude in left-right-symmetric models, and in diquark scalar models this contribution is two orders of magnitude larger than other contributions

How cores grow by pebble accretion. I. Direct core growth

Science.gov (United States)

Brouwers, M. G.; Vazan, A.; Ormel, C. W.

2018-03-01

Context. Planet formation by pebble accretion is an alternative to planetesimal-driven core accretion. In this scenario, planets grow by the accretion of cm- to m-sized pebbles instead of km-sized planetesimals. One of the main differences with planetesimal-driven core accretion is the increased thermal ablation experienced by pebbles. This can provide early enrichment to the planet's envelope, which influences its subsequent evolution and changes the process of core growth. Aims: We aim to predict core masses and envelope compositions of planets that form by pebble accretion and compare mass deposition of pebbles to planetesimals. Specifically, we calculate the core mass where pebbles completely evaporate and are absorbed before reaching the core, which signifies the end of direct core growth. Methods: We model the early growth of a protoplanet by calculating the structure of its envelope, taking into account the fate of impacting pebbles or planetesimals. The region where high-Z material can exist in vapor form is determined by the temperature-dependent vapor pressure. We include enrichment effects by locally modifying the mean molecular weight of the envelope. Results: In the pebble case, three phases of core growth can be identified. In the first phase (Mcore mixes outwards, slowing core growth. In the third phase (Mcore > 0.5M⊕), the high-Z inner region expands outwards, absorbing an increasing fraction of the ablated material as vapor. Rainout ends before the core mass reaches 0.6 M⊕, terminating direct core growth. In the case of icy H2O pebbles, this happens before 0.1 M⊕. Conclusions: Our results indicate that pebble accretion can directly form rocky cores up to only 0.6 M⊕, and is unable to form similarly sized icy cores. Subsequent core growth can proceed indirectly when the planet cools, provided it is able to retain its high-Z material.

Comet formation

Science.gov (United States)

Blum, J.

2014-07-01

There has been vast progress in our understanding of planetesimal formation over the past decades, owing to a number of laboratory experiments as well as to refined models of dust and ice agglomeration in protoplanetary disks. Coagulation rapidly forms cm-sized ''pebbles'' by direct sticking in collisions at low velocities (Güttler et al. 2010; Zsom et al. 2010). For the further growth, two model approaches are currently being discussed: (1) Local concentration of pebbles in nebular instabilities until gravitational instability occurs (Johansen et al. 2007). (2) A competition between fragmentation and mass transfer in collisions among the dusty bodies, in which a few ''lucky winners'' make it to planetesimal sizes (Windmark et al. 2012a,b; Garaud et al. 2013). Predictions of the physical properties of the resulting bodies in both models allow a distinction of the two formation scenarios of planetesimals. In particular, the tensile strength (i.e, the inner cohesion) of the planetesimals differ widely between the two models (Skorov & Blum 2012; Blum et al. 2014). While model (1) predicts tensile strengths on the order of ˜ 1 Pa, model (2) results in rather compactified dusty bodies with tensile strengths in the kPa regime. If comets are km-sized survivors of the planetesimal-formation era, they should in principle hold the secret of their formation process. Water ice is the prime volatile responsible for the activity of comets. Thermophysical models of the heat and mass transport close to the comet-nucleus surface predict water-ice sublimation temperatures that relate to maximum sublimation pressures well below the kPa regime predicted for formation scenario (2). Model (1), however, is in agreement with the observed dust and gas activity of comets. Thus, a formation scenario for cometesimals involving gravitational instability is favored (Blum et al. 2014).

Contribution of franchise research to entrepreneurship: a review and new opportunities

OpenAIRE

Larty, J

2010-01-01

This paper examines the relationship between franchising and entrepreneurship. The paper begins with a review of studies on franchising in leading entrepreneurship and management journals over a 12 year period. It illustrates how although the franchisor, franchise and the franchise organization are important elements of entrepreneurship, there has been only a tenuous link in the contribution of studies in franchising to entrepreneurship theorising and vice versa. The paper suggests fruitful n...

JAERI contribution to the 19th IAEA Fusion Energy Conference

International Nuclear Information System (INIS)

2003-03-01

This report compiles the contributed papers and presentation materials from JAERI to the 19th IAEA Fusion Energy Conference held at Lyon, France, from October 14th to 19th, 2002. The papers describe the recent progress in the experimental research in JT-60U and JFT-2M tokamaks, theoretical studies, fusion technology and R and D for ITER and fusion reactors. Total 32 papers consist of 1 overview talk, 14 oral and 17 poster presentations. Eight papers written by authors from other institutes and universities under collaboration with JAERI are also included. The 40 of the presented papers are indexed individually. (J.P.N.)

THE CONTRIBUTION OF PUBLIC INTEREST RESEARCH TO TRANSPORTATION POLICY

OpenAIRE

Makoto ITOH

2003-01-01

Established in 1995 with the basic philosophy of serving as a bridge between research and practice, the Institute for Transport Policy Studies conducts activities in support of transportation policy research in the public interest. This paper aims to describe the contribution of public interest research to transportation policy as seen in the Institute's activities. Touching first on the context and events leading to its establishment, the paper then describes the Institute's guiding principl...

Contributions to the 14th Symposium on fusion technology

International Nuclear Information System (INIS)

Andreani, R.

1987-01-01

The ENEA contributions to the 14. Symposium on fusion technology is represented by 15 papers. They are dealing mainly with the FTU (Frascati Tokamak Upgrade), a device under construction, through which high densities and confinement times will be obtained

CAPTURE OF TROJANS BY JUMPING JUPITER

International Nuclear Information System (INIS)

Nesvorný, David; Vokrouhlický, 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 observed asymmetry in the number of leading and trailing Trojans. We find that the capture probability is (6-8) × 10 –7 for each particle in the original transplanetary disk, implying that the disk contained (3-4) × 10 7 planetesimals with absolute magnitude H disk ∼ 14-28 M Earth , is consistent with the mass deduced from recent dynamical simulations of the planetary instability.

Safety of transport of radioactive material. Contributed papers

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-07-01

Radioactive material has been transported for decades within and between countries as the use of radioactive material to benefit mankind has expanded. The transport can involve many types of materials (radionuclides and radiation sources for applications in agriculture, energy production, industry, and medicine) and all modes of transport (road, rail, sea and waterways, and air). Among the organizations in the United Nations system, the International Atomic Energy Agency (IAEA) has the statutory function to establish or adopt standards of safety for protection of health against exposure to ionizing radiation. Within its statutory mandate and pursuant to this request, in 1961, the IAEA issued Regulations for the Safe Transport of Radioactive Material (the IAEA Transport Regulations). The Transport Regulations were periodically reviewed and, as appropriate, have been amended or revised. The latest version of the Transport Regulations was issued in 2000 by the IAEA as Publication TS-R-1 (ST-1, Revised). In addition, the IAEA is entrusted by its Statute to provide for the application of its standards at the request of States. The objective of the Conference is to foster the exchange of information on issues related to the safety of transport of radioactive material by providing an opportunity for representatives from sponsoring international organizations and their Member States and from other co-operating and participating organizations to discuss critical issues relating to the safety of transport of radioactive material by all modes and to formulate recommendations, as appropriate, regarding further international co-operation in this area. The following topics have been identified by the Technical Programme Committee as the subjects to be covered in the background briefing sessions: History and Status of the IAEA Transport Regulation Development; Experience in adoption of the IAEA Transport Regulations at the international level; Implementation of the IAEA Transport Regulations and other related requirements at the modal level; Experience in application of the IAEA Transport Regulations; Summary of actions (present and future) on security in transport of radioactive material (including actions at the IAEA). The following topics have been identified as the subjects to be covered: Liability in the Transport of Radioactive Material; Effectiveness of the Regulatory Process at the Member State Level; Adequacy of Safety Requirements; Effectiveness of Radiation Protection in Transport; Packaging and Transport of Nuclear Fuel Cycle Material; Packaging and Transport of Non Nuclear Fuel Cycle Radioactive Material; Packaging and Transport of Non-standard Radioactive Materials; Compliance Assurance and Quality Assurance; Emergency Preparedness and Response.

Original Paper Contribution of sacred forests to biodiversity ...

African Journals Online (AJOL)

Regarding plant diversity, a total of 75 species (68 tree species and 7 herbaceous species) distributed in 70 genera and 40 ... assess the natural stand structure in forests. ..... multiple sequential rites that have the power ... divinities and wind.

Boris Novozhilov: Life and contribution to the physics of combustion

Science.gov (United States)

Novozhilov, Vasily

2018-04-01

Professor Boris Novozhilov (1930-2017) passed away on February 19th, 2017 in Moscow. The present paper provides brief account of his life and contributions to the physics of combustion. From extensive scientific legacy left by Boris, several major achievements are discussed here: Zeldovich-Novozhilov (ZN) theory of unsteady solid propellant combustion, contributions to thermal explosion theory, the theory of spin combustion, discovery of propellant combustion transition to chaotic regimes through Feigenbaum period bifurcation scenario.

Birds and frogs selected papers, 1990-2014

CERN Document Server

Dyson, Freeman J

2015-01-01

This book is a sequel to the volume of selected papers of Dyson up to 1990 that was published by the American Mathematical Society in 1996. The present edition comprises a collection of the most interesting writings of Freeman Dyson, all personally selected by the author, from the period 1990–2014. The five sections start off with an Introduction, followed by Talks about Science, Memoirs, Politics and History, and some Technical Papers. The most noteworthy is a lecture entitled Birds and Frogs to the American Mathematical Society that describes two kinds of mathematicians with examples from real life. Other invaluable contributions include an important tribute to C. N. Yang written for his retirement banquet at Stony Brook University, as well as a historical account of the Operational Research at RAF Bomber Command in World War II provocatively titled A Failure of Intelligence. The final section carries the open-ended question of whether any conceivable experiment could detect single gravitons to provide d...

A student's guide to Einstein's major papers

CERN Document Server

Kennedy, Robert E

2012-01-01

Our understanding of the physical universe underwent a revolution in the early twentieth century - evolving from the classical physics of Newton, Galileo, and Maxwell to the modern physics of relativity and quantum mechanics. The dominant figure in this revolutionary change was Albert Einstein. In a single year, 1905, Einstein produced breakthrough works in three areas of physics: on the size and the effects of atoms; on the quantization of the electromagnetic field; and on the special theory of relativity. In 1916 he produced a fourth breakthrough work, the general theory of relativity. A Student's Guide to Einstein's Major Papers focuses on Einstein's contributions, setting his major works into their historical context, and then takes the reader through the details of each paper, including the mathematics. This book helps the reader appreciate the simplicity and insightfulness of Einstein's ideas and how revolutionary his work was, and locate it in the evolution of scientific thought begun by the ancient...

Understanding the CDM's contribution to technology transfer

International Nuclear Information System (INIS)

Schneider, Malte; Holzer, Andreas; Hoffmann, Volker H.

2008-01-01

Developing countries are increasingly contributing to global greenhouse gas emissions and, consequently, climate change as a result of their rapid economic growth. In order to reduce their impact, the private sector needs to be engaged in the transfer of low-carbon technology to those countries. The Clean Development Mechanism (CDM) is currently the only market mechanism aimed at triggering changes in the pattern of emissions-intensive activities in developing countries and is likely to play a role in future negotiations. In this paper, we analyse how the CDM contributes to technology transfer. We first develop a framework from the literature that delineates the main factors which characterise technology transfer. Second, we apply this framework to the CDM by assessing existing empirical studies and drawing on additional expert interviews. We find that the CDM does contribute to technology transfer by lowering several technology-transfer barriers and by raising the transfer quality. On the basis of this analysis, we give preliminary policy recommendations

A neglected FDI contribution – Arne Lund (1944)

DEFF Research Database (Denmark)

Pedersen, Kurt; Strandskov, Jesper

2010-01-01

of international production. Significant parts of the contributions to the theories of foreign direct investments had, however, been presented in a coherent and systematic way by the Danish economist Arne Lund in an article in Nationaløkonomisk Tidsskrift in 1944. The purpose of this paper is to present Lund...

The relative contributions of climatic elements and environmental ...

African Journals Online (AJOL)

The aim of this paper was to determine the relative contributions of climatic elements and environmental factors to urban flooding in Awka urban area of Anambra State. Towards achieving this aim, 10 year (2000-2009) meteorological data of temperature and rainfall of the study area were collected from synoptic ...

Human action contribution to ET-RR-II reactor systems unstems unavailability

International Nuclear Information System (INIS)

Sabek, M.G.

2001-01-01

This paper gives a study on the human action contribution to the systems unavailability of ET-RR-II reactor as a result of the test and maintenance procedures. The human contribution is expressed in terms of Fussel-Vesely importance which is defined by the probability that event is contributing to system failure (unavailability). The human error basic events contribution was analyzed for all initiating events and systems fault trees. The calculations result shows a high contribution value (61%) for the human error to systems unavailability. This means that the operator and the maintenance people should be highly qualified trained. Moreover, there should be programs for continuous training. Also, the procedures of tests and maintenance should be in a simple way and clear in order to minimize the contribution of the human errors. The calculations were done using the IRRAS cods

Eleven years of net network research activity - inr contributions

International Nuclear Information System (INIS)

Deaconu, V.; Ionita, I.; Meleg, T.; Deaconu, M.; Truta, C.; Oncioiu, G.

2013-01-01

The European Network on Neutron Techniques Standardization for Structural Integrity (NeT) was established in 2002, grouping institutions from industry, research and academic media. Coordinated by the European Commission.s Joint Research Centre, the main mission of this network is to develop experimental and numerical techniques and standards for the reliable characterisation of residual stresses in structural welds. Each problem is tackled by creating a dedicated Task Group which manages measurement and modelling round robin studies and undertakes a thorough analysis and interpretation of the results. Over forty institutions are active NeT partners, their specific involvement and contributions being summarised in this paper. The Institute for Nuclear Research Pitesti (INR) is one of NeT founders and its contribution is related to numerical modelling, specimen analysis, material characterisation, data analysis or SANS support. This is also emphasised throughout this paper, together with the specific NeT research topics presentation. (authors)

[Hierarchical structure of authors collaboration. An analysis of papers on imaging diagnosis published by hospital radiology departments in Comunidad Valenciana (1994-2001)].

Science.gov (United States)

Miguel-Dasit, A; Martí-Bonmatí, L; Sanfeliu, P; Aleixandre, R; Valderrama, J C

2005-06-01

Analyze the different contribution of hierarchical categories in the papers published by radiologists of hospitals belonging to Comunidad Valenciana along the period 1994-2001, as well as their distribution in the different journals. For the recovery of the papers sample we have designed specific search profiles for EMI and Medline databases. Hierarchical category of the authors was identified through personal interviews. We have analyzed 417 works, with 1,321 authors distributed in the following form: chief of service, 8.8%; chief of section, 12.4%; assistant physician, 50.7%, and resident, 28%. Hierarchical groupings with participation of residents were more consistent for publishing papers along all the study period (1994-2001). Higher percentage of papers (21%) corresponded to grouping. Radiología was the most productive journal (42% papers). All results were statistically significant (p Comunidad Valenciana hospitals showed an active participation in research papers published along the period 1994-2001, in collaboration with the rest of the hierarchical categories, basically with the assistant physician. Assistant physicians contributed most of papers. Chief of section and chief of department contributed fifth of papers.

Mobilising voluntary contributions in public urban regeneration – a review

DEFF Research Database (Denmark)

Larsen, Jacob Norvig; Jensen, Jesper Ole; Agger, Annika

Research on volunteerism indicates that one third of all adults in Denmark regularly contribute with voluntary labour in social relief work, community-based organizations, non-governmental organizations, or otherwise. In this paper we ask if and how urban regeneration might benefit from...... in relation to public policy arenas and activities, particularly within urban policy and the community development fields. A categorization is proposed as regards different ways and models of civic engagement and major challenges are outlined. The paper is first step of a research project exploring potential...... the apparently strong growth in voluntarism. Although there seems to be a large potential for involving volunteers and voluntary organisations, systematic analysis of recent years’ urban regeneration projects in Denmark shows that the sustainability of voluntary contributions is limited. While initial enrolling...

A Contribution Towards A Grammar of Code

Directory of Open Access Journals (Sweden)

David M. Berry

2008-01-01

Full Text Available Over the past thirty years there has been an increasing interest in the social and cultural implications of digital technologies and ‘informationalism’ from the social sciences and humanities. Generally this has concentrated on the implications of the “convergence” of digital devices and services, understood as linked to the discrete processing capabilities of computers, which rely on logical operations, binary processing and symbolic representation. In this paper, I wish to suggest that a ‘grammar of code’ might provide a useful way of thinking about the way in which digital technologies operate as a medium and can contribute usefully to this wider debate. I am interested in the way in which the dynamic properties of code can be understood as operating according to a grammar reflected in its materialisation and operation in the lifeworld – the discretisation of the phenomenal world. As part of that contribution in this paper I develop some tentative Weberian ‘ideal-types’. These ideal-types are then applied to the work of the Japanese composer, Masahiro Miwa, whose innovative ‘Reverse-Simulation music’ models the operation of basic low-level digital circuitry for the performance and generation of musical pieces.

Reflective Practice: Eight Stages of Publishing a Scientific Research Paper

Directory of Open Access Journals (Sweden)

Stephen K. Donovan

2018-03-01

Full Text Available This paper suggests a methodology of academic paper classification for the scientist intending to contribute to peer-reviewed scientific literature. This will enable the progress of the typescript through the publication system to be accurately determined at any stage. The publication process is split into eight subdivisions of differing worth and import: in navel contemplation; in preparation; submitted; in review; revision, revised, and resubmitted; accepted; in press; and publication. Papers in navel contemplation are referred to as in preparation by many, which can be an embarrassment when asked exactly what has been prepared. Rather than listing papers as in preparation in academic submissions, it is better to list them as unpublished data until published. Efficient authors keep a close watch on their papers between submission and the proof stage. They must be sufficiently organized to manage their publications and to be aware when things slow down. The methodology is flexible and, if it does not work for some authors, then they have a simple framework to adapt to their own preferences. In short, scientists need to show care and not be overly optimistic about the progress of any paper.

EURATOM-CEA association contributions to the 21st symposium on fusion technology

International Nuclear Information System (INIS)

Garin, P.; Grosman, A.; Beaumont, B.

2000-11-01

The 27 contributions of EURATOM-Cea association have been gathered with 6 additional papers and 1 invited paper in this document. Most papers concern Tore-Supra and deal with the ergodic divertor, particle injection, impedance concept for ICRF antennas, low hybrid current drive, RF systems, the 118 GHz ECRH experiment, the inner first wall, improved vacuum vessel protection, pellet injection, material activation, and the CIEL project. 3 of the additional papers concern the model coil of ITER

EURATOM-CEA association contributions to the 21st symposium on fusion technology

Energy Technology Data Exchange (ETDEWEB)

Garin, P; Grosman, A; Beaumont, B [and others

2000-11-01

The 27 contributions of EURATOM-Cea association have been gathered with 6 additional papers and 1 invited paper in this document. Most papers concern Tore-Supra and deal with the ergodic divertor, particle injection, impedance concept for ICRF antennas, low hybrid current drive, RF systems, the 118 GHz ECRH experiment, the inner first wall, improved vacuum vessel protection, pellet injection, material activation, and the CIEL project. 3 of the additional papers concern the model coil of ITER.

Contributions of Literature to Social Psychology

Directory of Open Access Journals (Sweden)

Anastasio Ovejero

2012-11-01

Full Text Available There are two main kind of psychology: a intuitive psychology, and an academic and professional psychology. These two psychologies are different, but they can make important reciprocals contributions. And the best of the intuitive psychology, that in my opinion is in the literature and overall in the romance, can be very useful for professional psychologists. The main end of this paper is to show how the social psychologists can learn from the intuitive psychology of the great romances. This contribution of the romance to the social psychology is, at least, at these two levels. At the level of construction of the subjectivity and the modern subject and the, therefore, of the psychology’s arise, and at the level of some concrete subjects studied by the psychologists (romantic love, jealousy, infidelity, compunction, emotions, vengeance, human relations…

Actinides compounds for the transmutation: scientific contributions of american and japanese collaborations

International Nuclear Information System (INIS)

Raison, Ph.; Albiot, T.

2000-01-01

This paper deals with the minor actinides transmutation and the scientific contribution of the ORNL and the JAERI. It presents researches on the Am-Zr-Y-O system in the framework of the heterogeneous reprocessing, the curium and pyrochlore structures, with the ORNL contribution and phase diagrams, data of Thermodynamics, actinides nitrides, with the JAERI. (A.L.B.)

CALL FOR PAPERS: Special issue on the random search problem: trends and perspectives

Science.gov (United States)

da Luz, Marcos G. E.; Grosberg, Alexander Y.; Raposo, Ernesto P.; Viswanathan, Gandhi M.

2008-11-01

field. The subject can be approached from the perspective of different fields: ecology, networks, transport problems, molecular biology, etc. The study of the problem is particularly suited to the concepts and methods of statistical physics and stochastic processes; for example, fractals, random walks, anomalous diffusion. Discrete landscapes can be approached via graph theory, random lattices and complex networks. Such topics are regularly discussed in Journal of Physics A: Mathematical and Theoretical. All such aspects of the problem fall within the scope and focus of this special issue on the random search problem: trends and perspectives. Editorial policy All contributions to the special issue will be refereed in accordance with the refereeing policy of the journal. In particular, all research papers will be expected to be original work reporting substantial new results. The issue will also contain a number of review articles by invitation only. The Guest Editors reserve the right to judge whether a contribution fits the scope of the special issue. Guidelines for preparation of contributions We aim to publish the special issue in August 2009. To realize this, the DEADLINE for contributed papers is 15 January 2009. There is a page limit of 15 printed pages (approximately 9000 words) per contribution. For papers exceeding this limit, the Guest Editors reserve the right to request a reduction in length. Further advice on document preparation can be found at www.iop.org/Journals/jphysa. Contributions to the special issue should if possible be submitted electronically by web upload at www.iop.org/Journals/jphysa, or by email to jphysa@iop.org, quoting 'J. Phys. A Special Issue— Random Search Problem'. Please state whether the paper has been invited or is contributed. Submissions should ideally be in standard LaTeX form. Please see the website for further information on electronic submissions. Authors unable to submit electronically may send hard-copy contributions to

Editorial Note: Review Papers for Journal of Risk and Financial Management (JRFM

Directory of Open Access Journals (Sweden)

Michael McAleer

2018-04-01

Full Text Available The Journal of Risk and Financial Management (JRFM was inaugurated in 2008 and has continued publishing successfully with Volume 11 in 2018. Since the journal was established, JRFM has published in excess of 110 topical and interesting theoretical and empirical papers in financial economics, financial econometrics, banking, finance, mathematical finance, statistical finance, accounting, decision sciences, information management, tourism economics and finance, international rankings of journals in financial economics, and bibliometric rankings of journals in cognate disciplines. Papers published in the journal range from novel technical and theoretical papers to innovative empirical contributions. The journal wishes to encourage critical review papers on topical subjects in any of the topics mentioned above in financial economics and in cognate disciplines.

Exploring Paper.

Science.gov (United States)

Brand, Judith, Ed.

1999-01-01

Exploratorium Magazine communicates ideas that exhibits cannot easily demonstrate, extending the museum beyond its physical walls. This issue takes an in-depth look at the science and history of paper. Topics include: (1) Fascinating Facts about Paper; (2) A Closer Look at the Paper in This Magazine; (3) Handmade Paper; (4) Paper Airplanes; (5)…

Business Council's position paper on domestic greenhouse policy

International Nuclear Information System (INIS)

1995-01-01

The views of business on government policy issues relating to greenhouse gas abatement are outlined in this paper. While recognizing the need for Australia to make an effective and equitable contribution to global greenhouse gas abatement, it does not believe that acceptance of the targets and timetables implied in the Climate Change Convention will necessarily lead to Australia making an equitable contribution. The feeling is that Australia should adopt a 'no-regrets' approach in line with other OECD countries. This approach includes micro economic reform policies such as emission reduction in energy transport, land management and sink enhancement. Programs fostering relevant research and development in these areas should be adopted. Business is opposed to any form of carbon tax or environmental levy, or any reduction in the diesel fuel rebate. It is believed that the potential of no-regrets measures will be most effectively achieved through a policy package involving mutually supportive government and industry actions. 1 photo

School Processes That Can Drive Scaling-Up of an Innovation, or Contribute to Its Abandonment. Conference Paper

Science.gov (United States)

Zacamy, Jenna; Newman, Denis; Lazarev, Valeriy; Lin, Li

2015-01-01

This paper reports findings from a multi-year study of the scale-up of Reading Apprenticeship (RA), an approach to improve academic literacy by helping teachers provide the support students need to be successful readers in the content areas. WestEd's Strategic Literacy Initiative (SLI), began developing the program in 1995 and has since reached…

Announcement, observation and honesty in the voluntary contributions game

NARCIS (Netherlands)

Denant-Boemont, L.; Masclet, D.; Noussair, C.N.

2011-01-01

In this paper, we study the effect of pre-play announcements and ex-post observation of decisions on voluntary public good provision. We find that requiring announcements, in conjunction with making contribution decisions public, has a significantly positive effect on the average level of

Hydropower's Contribution to Energy Security

Energy Technology Data Exchange (ETDEWEB)

Altinbilek, D.; Abdel-Malek, R.; Devernay, J.M.; Gill, R.; Leney, S.; Moss, Terry; Schiffer, H.P.; Taylor, R.M.

2007-07-01

The role of hydropower within mixed power systems is analysed from the point of view of both quantitative and qualitative performance. Interrelationships with all other generation technologies are discussed and synergies identified. Resources, sustainability criteria and investment challenges are reviewed in the context of development. The objective of the paper is to define hydropower's contribution within the clean, clever and competitive markets of the future.

White paper on science and technology, 1990

International Nuclear Information System (INIS)

1991-01-01

Today, it is apparent that science and technology are major driving force for nation's economic growth. Japan is utilizing its scientific and technological ability to produce superior products. Thus Japan has become an economic giant. The citizenry of Japan are enjoying the benefits of these scientific and technological advances. In recent years, the socioeconomic situation in the country has improved. As a result, the people of Japan want the quality of life in addition to material goods. There are expectations for improving the quality of life, while at the same time, solving such problems as the aging of the society and global environmental concerns. From these perspectives, in this paper, how science and technology have contributed to improve the quality of life and how those have been applied are analyzed. It is hoped that this paper is useful as a basic reference in considering Japanese socioeconomic goals for the 21st century. Furthermore, the government tries to address the problems pointed out in this paper, and promote the advancement of Japanese science and technology. The status of Japanese science and technology, expectations for science and technology and the science and technology policy in foreign countries and Japan are described. (K.I.)

EFFECTS OF DYNAMICAL EVOLUTION OF GIANT PLANETS ON THE DELIVERY OF ATMOPHILE ELEMENTS DURING TERRESTRIAL PLANET FORMATION

Energy Technology Data Exchange (ETDEWEB)

Matsumura, Soko [School of Engineering, Physics, and Mathematics, University of Dundee, DD1 4HN, Scotland (United Kingdom); Brasser, Ramon; Ida, Shigeru, E-mail: s.matsumura@dundee.ac.uk [Earth-Life Science Institute, Tokyo Institute of Technology, Meguro-ku, Tokyo, 152-8550 (Japan)

2016-02-10

Recent observations started revealing the compositions of protostellar disks and planets beyond the solar system. In this paper, we explore how the compositions of terrestrial planets are affected by the dynamical evolution of giant planets. We estimate the initial compositions of the building blocks of these rocky planets by using a simple condensation model, and numerically study the compositions of planets formed in a few different formation models of the solar system. We find that the abundances of refractory and moderately volatile elements are nearly independent of formation models, and that all the models could reproduce the abundances of these elements of the Earth. The abundances of atmophile elements, on the other hand, depend on the scattering rate of icy planetesimals into the inner disk, as well as the mixing rate of the inner planetesimal disk. For the classical formation model, neither of these mechanisms are efficient and the accretion of atmophile elements during the final assembly of terrestrial planets appears to be difficult. For the Grand Tack model, both of these mechanisms are efficient, which leads to a relatively uniform accretion of atmophile elements in the inner disk. It is also possible to have a “hybrid” scenario where the mixing is not very efficient but the scattering is efficient. The abundances of atmophile elements in this case increase with orbital radii. Such a scenario may occur in some of the extrasolar planetary systems, which are not accompanied by giant planets or those without strong perturbations from giants. We also confirm that the Grand Tack scenario leads to the distribution of asteroid analogues where rocky planetesimals tend to exist interior to icy ones, and show that their overall compositions are consistent with S-type and C-type chondrites, respectively.

EFFECTS OF DYNAMICAL EVOLUTION OF GIANT PLANETS ON THE DELIVERY OF ATMOPHILE ELEMENTS DURING TERRESTRIAL PLANET FORMATION

International Nuclear Information System (INIS)

Matsumura, Soko; Brasser, Ramon; Ida, Shigeru

2016-01-01

Recent observations started revealing the compositions of protostellar disks and planets beyond the solar system. In this paper, we explore how the compositions of terrestrial planets are affected by the dynamical evolution of giant planets. We estimate the initial compositions of the building blocks of these rocky planets by using a simple condensation model, and numerically study the compositions of planets formed in a few different formation models of the solar system. We find that the abundances of refractory and moderately volatile elements are nearly independent of formation models, and that all the models could reproduce the abundances of these elements of the Earth. The abundances of atmophile elements, on the other hand, depend on the scattering rate of icy planetesimals into the inner disk, as well as the mixing rate of the inner planetesimal disk. For the classical formation model, neither of these mechanisms are efficient and the accretion of atmophile elements during the final assembly of terrestrial planets appears to be difficult. For the Grand Tack model, both of these mechanisms are efficient, which leads to a relatively uniform accretion of atmophile elements in the inner disk. It is also possible to have a “hybrid” scenario where the mixing is not very efficient but the scattering is efficient. The abundances of atmophile elements in this case increase with orbital radii. Such a scenario may occur in some of the extrasolar planetary systems, which are not accompanied by giant planets or those without strong perturbations from giants. We also confirm that the Grand Tack scenario leads to the distribution of asteroid analogues where rocky planetesimals tend to exist interior to icy ones, and show that their overall compositions are consistent with S-type and C-type chondrites, respectively

Arizona Libraries: Books to Bytes. Contributed Papers Presented at the AzLA Annual Conference (Phoenix, Arizona, November 17-18, 1995).

Science.gov (United States)

Hammond, Carol, Ed.

This document contains three papers presented at the 1995 Arizona Library Association conference. Papers include: (1) "ERLs and URLs: ASU Libraries Database Delivery Through Web Technology" (Dennis Brunning & Philip Konomos), which illustrates how and why the libraries at Arizona State University developed a world wide web server and…

Determining factors that contribute to financial literacy for small and medium enterprises

Science.gov (United States)

Hakim, M. S.; Oktavianti, V.; Gunarta, I. K.

2018-04-01

Financial literacy on the SME owner/manager will subsequently improve the profitability of SME. Although, numerous research had existed in financial literacy subject, there are still limited research that examined the factor related to financial literacy. In this paper, we are examining demographic and SME factor that contribute to financial literacy using linear regression. Other objective of this paper is to confirm the benefit of financial literacy on access to credit. The finding shown that for demographic factor, level of education is contributed to financial literacy. The second finding is that level of financial literacy is related with greater degree of access to credit

[Agrochemicals and human health: contributions of healthcare professionals].

Science.gov (United States)

de Siqueira, Soraia Lemos; Kruse, Maria Henriqueta Luce

2008-09-01

This paper focuses on the scientific production of health professionals, especially nurses, about agrochemicals and human health. The essay combines and presents information by means of literature review, with a view to acknowledge the contribution of each author and their use for the human health field. Thirty-two research articles, published in Brazilian journals, were located. The analysis of these articles highlights that healthcare professionals' contributions focus on human health, especially, workers' health and food quality. With a view to minimize the effects from agrochemicals on human and environmental health, the authors exposes action suggestions both for health professionals and for the institutions associated.

International symposium on macromolecules (SIM), Rio de Janeiro, Brazil, 26--31 July 1974. Contributed papers: abstracts and discussion

Energy Technology Data Exchange (ETDEWEB)

Mano, E B; Tabak, D; Tarvin, R F; von Dietrich, C P; de Souza Gomes, A [eds.

1974-07-01

Abstracts of the papers presented are compiled. The Symposium considered four topics: polymer chemistry, polymer physical chemistry, polymer technology, and biopolymers. A companion volume contains the discussions relating to various presentations. (JSR)

Paper electronics.

Science.gov (United States)

Tobjörk, Daniel; Österbacka, Ronald

2011-05-03

Paper is ubiquitous in everyday life and a truly low-cost substrate. The use of paper substrates could be extended even further, if electronic applications would be applied next to or below the printed graphics. However, applying electronics on paper is challenging. The paper surface is not only very rough compared to plastics, but is also porous. While this is detrimental for most electronic devices manufactured directly onto paper substrates, there are also approaches that are compatible with the rough and absorptive paper surface. In this review, recent advances and possibilities of these approaches are evaluated and the limitations of paper electronics are discussed. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Acoustical contribution calculation and analysis of compressor shell based on acoustic transfer vector method

Science.gov (United States)

Chen, Xiaol; Guo, Bei; Tuo, Jinliang; Zhou, Ruixin; Lu, Yang

2017-08-01

Nowadays, people are paying more and more attention to the noise reduction of household refrigerator compressor. This paper established a sound field bounded by compressor shell and ISO3744 standard field points. The Acoustic Transfer Vector (ATV) in the sound field radiated by a refrigerator compressor shell were calculated which fits the test result preferably. Then the compressor shell surface is divided into several parts. Based on Acoustic Transfer Vector approach, the sound pressure contribution to the field points and the sound power contribution to the sound field of each part were calculated. To obtain the noise radiation in the sound field, the sound pressure cloud charts were analyzed, and the contribution curves in different frequency of each part were acquired. Meanwhile, the sound power contribution of each part in different frequency was analyzed, to ensure those parts where contributes larger sound power. Through the analysis of acoustic contribution, those parts where radiate larger noise on the compressor shell were determined. This paper provides a credible and effective approach on the structure optimal design of refrigerator compressor shell, which is meaningful in the noise and vibration reduction.

Dark matter in the outer solar system

Science.gov (United States)

Owen, T.; Cruikshank, D.; De Bergh, C.; Geballe, T.

1994-01-01

There are now a large number of small bodies in the outer solar system that are known to be covered with dark material. Attempts to identify that material have been thwarted by the absence of discrete absorption features in the reflection spectra of these planetesimals. An absorption at 2.2 micrometers that appeared to be present in several objects has not been confirmed by new observations. Three absorptions in the spectrum of the unusually red planetesimal 5145 Pholus are well-established, but their identity remains a mystery.

Elements that contribute to boost female entrepreneurship: A prospective analysis

Directory of Open Access Journals (Sweden)

Pilar Ortiz García

2016-06-01

Full Text Available This paper aims to identify what environmental modulators elements favor and contribute to enhance female entrepreneurship from a gender perspective. The qualitative study draws on 10 interviews in depth after being tested on their contents, from a relational perspective, allow a set of conclusions and recommendations that contribute to the empowerment of women entrepreneurs figure. The results highlight the importance of social support and comprehensive training in creating a culture that promotes and makes visible the role of women entrepreneurs.

BOOK REVIEW: A Student's Guide to Einstein's Major Papers A Student's Guide to Einstein's Major Papers

Science.gov (United States)

Janssen, Michel

2013-12-01

The core of this volume is formed by four chapters (2-5) with detailed reconstructions of the arguments and derivations in four of Einstein's most important papers, the three main papers of his annus mirabilis 1905 (on the light quantum, Brownian motion, and special relativity) and his first systematic exposition of general relativity of 1916. The derivations are given in sufficient detail and in sufficiently modernized notation (without any serious distortion of the originals) for an undergraduate physics major to read and understand them with far less effort than it would take him or her to understand (English translations of) Einstein's original papers. Each of these four papers is accompanied by a detailed introduction, which covers the conceptual development of the relevant field prior to Einstein's contribution to it and corrects some of the myths surrounding these papers that still have not been fully eradicated among physicists. (One quibble: though Kennedy correctly points out that the goal of the light quantum paper was not to explain the photoelectric effect, it is also not quite right to say that 'it was written to explain the Wien region of blackbody radiation' (p. xv). Einstein used this explanatory feat as the central argument for his light quantum hypothesis.) These four chapters then are the most valuable part of the volume. They could be used, independently of one another, but preferably in conjunction with Einstein's original texts, in courses on quantum mechanics, statistical mechanics, electrodynamics, and general relativity, respectively, to add a historical component to such courses. As a historian of science embedded in a physics department who is regularly called upon to give guest lectures in such courses on the history of their subjects, I can highly recommend the volume for this purpose. However, I would not adopt this volume as (one of) the central text(s) for a course on the history of modern physics. For one thing, chapter 1, which in

Contributions for the seventeenth biennial conference on carbon

International Nuclear Information System (INIS)

Delle, W.

1985-06-01

This report is the compilation of the papers prepared by KFA Juelich GmbH for the 17th Biennial Conference on Carbon. In the contributions, results are presented which were obtained from the application of carbon in the High Temperature Gas-Cooled Reactor and for the Spallation Neutron Source planned in the Federal Republic of Germany. (orig.) [de

FORMING CHONDRULES IN IMPACT SPLASHES. II. VOLATILE RETENTION

Energy Technology Data Exchange (ETDEWEB)

Dullemond, Cornelis Petrus; Harsono, Daniel; Stammler, Sebastian Markus [Institute for Theoretical Astrophysics, Heidelberg University, Albert-Ueberle-Strasse 2, D-69120 Heidelberg (Germany); Johansen, Anders [Lund Observatory, Department of Astronomy and Theoretical Physics, Lund University, Box 43, SE-22100 Lund (Sweden)

2016-11-20

Solving the mystery of the origin of chondrules is one of the most elusive goals in the field of meteoritics. Recently, the idea of planet(esimal) collisions releasing splashes of lava droplets, long considered out of favor, has been reconsidered as a possible origin of chondrules by several papers. One of the main problems with this idea is the lack of quantitative and simple models that can be used to test this scenario by directly comparing to the many known observables of chondrules. In Paper I of this series, we presented a simple thermal evolution model of a spherically symmetric expanding cloud of molten lava droplets that is assumed to emerge from a collision between two planetesimals. The production of lava could be either because the two planetesimals were already in a largely molten (or almost molten) state due to heating by {sup 26}Al, or due to impact jetting at higher impact velocities. In the present paper, number II of this series, we use this model to calculate whether or not volatile elements such as Na and K will remain abundant in these droplets or whether they will get depleted due to evaporation. The high density of the droplet cloud (e.g., small distance between adjacent droplets) causes the vapor to quickly reach saturation pressure and thus shuts down further evaporation. We show to what extent, and under which conditions, this keeps the abundances of these elements high, as is seen in chondrules. We find that for most parameters of our model (cloud mass, expansion velocity, initial temperature) the volatile elements Mg, Si, and Fe remain entirely in the chondrules. The Na and K abundances inside the droplets will initially stay mostly at their initial values due to the saturation of the vapor pressure, but at some point start to drop due to the cloud expansion. However, as soon as the temperature starts to decrease, most or all of the vapor recondenses again. At the end, the Na and K elements retain most of their initial abundances, albeit

The Battle that Weber Lost: Exploring The Fate of Weber's Contribution to the Methodenstreit

DEFF Research Database (Denmark)

Jagd, Søren

This paper explores the outcome of Max Weber's contribution to the Methodenstreit between teh Austrian marginal utility economists and teh German historicist economists in his methodological writings. The main conclusion is the neither economists nor sociologists have found Weber's contribution...... worth a closer look. The result is that Weber's contribution never has found its way int the methodological discussions in economics as well as into economic sociology...

Estimating the contribution of the private power plant on electricity market in Korea

Energy Technology Data Exchange (ETDEWEB)

Sonn, Yang-Hoon; Park, Jong-Bae

2010-09-15

This paper aims to measure the contribution of merchant power provider in electricity market in Korea. In spite of the restructuring process of last one decade, wholesale power market is still dominated by KEPCO and its subsidiaries. The share of the public-owned power plants is 89% in capacity, and 96% in generation. The participation of the private power shows very significant contribution in promoting the competition in the market in spite of the small share. The conclusion of the paper is that we need to enhance the competition among suppliers in order to build stable electricity market for the consumer.

Large contribution to the neutron electric dipole moment from a dimension six four quark operator

International Nuclear Information System (INIS)

He, Xiaogang; McKellar, B.

1992-01-01

In this paper the contribution of a dimension six four quark operator (Q q ) to the neutron electric dipole moment was studied. It was found that this contribution dominates over other contributions by at least one order of magnitude in Left-Right symmetric models and two orders of magnitude in di-quark scalar models. 10 refs., 1 fig

Viking lander tracking contributions to Mars mapping

International Nuclear Information System (INIS)

Michael, W.H. Jr.

1979-01-01

The major recent advances in planetary mapping have been accomplished through use of photography from orbiting satellites, as is the case for Mars with Mariner and Viking photographs. The requirement for greater precision demands that inputs to the photogrammatic process be more precisely defined. This paper describes how analyses of Doppler and ranging data from the Viking landers are contributing to more precise mapping of Mars in several specific areas. (Auth.)

CO-AUTHORING SCIENTIFIC PAPERS IN MANAGEMENT: INTERNATIONAL ACADEMICS’ POINTS OF VIEW

Directory of Open Access Journals (Sweden)

Manuel Aníbal Silva Portugal Vasconcelos Ferreira

2015-12-01

Full Text Available Responding to institutional pressure to publish more papers, and in respected journals, management academics are seeking to increase their productivity by establishing co-authoring ties that speed up the process, from the initial stages of defining the research question to publication in a journal. Understanding the motives, benefits and hazards of co-authorship, especially using the experiences of highly reputed scholars, may help improve the efficiency and quality of research efforts. In this paper, we examine the responses to six questions sent to thirteen prolific international researchers, by email. In essence, we sought to understand such aspects as: the origins of co-authoring ties, the importance of having co-authors, the pitfalls of and methods for coordinating co-authorships, and what constitutes a contribution that warrants co-authorship. Results show that (1 international researchers evaluate their co-authorships positively, (2 many co-authorships emerge from prior supervision or personal proximity, more so than ties to the same institution, (3 the ordering of names is defined a priori and managed actively, (4 the benefits sought after are mainly specialization and complementary competences, (5 co-authorship is given based on actual contribution, albeit there are many forms of contribution, and (6 the pressure to publish, and an increasing difficulty of publishing in the top journals are the drivers of co-authorship. The analyses point to important insights for young Brazilian scholars.

Factors Contributing to the Subjective Career Success among Islamic Educators in Primary Schools

Directory of Open Access Journals (Sweden)

Mesnan Supa`ad

2013-07-01

Full Text Available A very limited research has been done in the field of career development among Islamic education teachers. Most of the previous researches showed an improvement in terms of grades, positions, and responsibilities of their previous routines as an indicator of their career advancement. However, this conceptual (concept paper discusses how personality factors, career planning, and career strategy can provide significant contribution to the success of Islamic education teachers’ career. Based on the Five Factor Model, Gould Planning Model, and the support of previous researches, this paper discusses how these three factors can contribute to the success of Islamic education teachers’ career. This paper also discusses its impact towards Islamic education teachers in Malaysia, schools management, District Education Office, Ministry of Education, and teachers education institutions.

Factors Contribute to Safety Culture in the Manufacturing Industry in Malaysia

OpenAIRE

Ong Choon Hee

2014-01-01

The purpose of this paper is to explain the role of safety culture in the manufacturing industry in Malaysia and identify factors contribute to safety culture. It is suggested in this study that leadership support, management commitment and safety management system are important factors that contribute to safety culture. This study also provides theoretical implications to guide future research and offers practical implications to the managers in the development of safety culture. Given that ...

The fifty highest cited papers in anterior cruciate ligament injury.

Science.gov (United States)

Vielgut, Ines; Dauwe, Jan; Leithner, Andreas; Holzer, Lukas A

2017-07-01

The anterior cruciate ligament (ACL) is one of the most common injured knee ligaments and at the same time, one of the most frequent injuries seen in the sport orthopaedic practice. Due to the clinical relevance of ACL injuries, numerous papers focussing on this topic including biomechanical-, basic science-, clinical- or animal studies, were published. The purpose of this study was to determine the most frequently cited scientific articles which address this subject, establish a ranking of the 50 highest cited papers and analyse them according to their characteristics. The 50 highest cited articles related to Anterior Cruciate Ligament Injury were searched in Thomson ISI Web of Science® by the use of defined search terms. All types of scientific papers with reference to our topic were ranked according to the absolute number of citations and analyzed for the following characteristics: journal title, year of publication, number of citations, citation density, geographic origin, article type and level of evidence. The 50 highest cited articles had up to 1624 citations. The top ten papers on this topic were cited 600 times at least. Most papers were published in the American Journal of Sports Medicine. The publication years spanned from 1941 to 2007, with the 1990s and 2000s accounting for half of the articles (n = 25). Seven countries contributed to the top 50 list, with the USA having by far the most contribution (n = 40). The majority of articles could be attributed to the category "Clinical Science & Outcome". Most of them represent a high level of evidence. Scientific articles in the field of ACL injury are highly cited. The majority of these articles are clinical studies that have a high level of evidence. Although most of the articles were published between 1990 and 2007, the highest cited articles in absolute and relative numbers were published in the early 1980s. These articles contain well established scoring- or classification systems. The

ASDEX contributions to the 17th European conference on controlled fusion and plasma heating

International Nuclear Information System (INIS)

1990-09-01

The 'ASDEX contributions to the 17th European conference on controlled fusion and plasma heating' (Amsterdam, June 25-29, 1990) hold one invited paper (Physics of enhanced confinement with peaked and board density profiles) and 12 chapters containing 44 contributed papers dealing with the following topics: Lower hybrid current drive and heating; Ion cyclotron heating; General confinement studies; Fluctuation studies; Direct measurement of transport coefficients; H-mode studies; Pellet studies; Divertor and SOL-studies; Impurity and impurity transport studies; Density limit studies; MHD studies; Diagnostic development. (orig./AH)

Women in numbers Europe II contributions to number theory and arithmetic geometry

CERN Document Server

Ozman, Ekin; Johnson-Leung, Jennifer; Newton, Rachel

2018-01-01

Inspired by the September 2016 conference of the same name, this second volume highlights recent research in a wide range of topics in contemporary number theory and arithmetic geometry. Research reports from projects started at the conference, expository papers describing ongoing research, and contributed papers from women number theorists outside the conference make up this diverse volume. Topics cover a broad range of topics such as arithmetic dynamics, failure of local-global principles, geometry in positive characteristics, and heights of algebraic integers. The use of tools from algebra, analysis and geometry, as well as computational methods exemplifies the wealth of techniques available to modern researchers in number theory. Exploring connections between different branches of mathematics and combining different points of view, these papers continue the tradition of supporting and highlighting the contributions of women number theorists at a variety of career stages. Perfect for students and researche...

Geographic Skills Mismatch, Job Search, and Race. Discussion Paper No. 1288-04

Science.gov (United States)

Stoll, Michael A.

2004-01-01

This paper examines whether a geographic skills mismatch exists between the location of less-educated minorities, in particular African Americans, and high-skill job concentrations, and if so, whether it contributes to the relatively poor employment outcomes of this group. It explores these questions by examining data on the recent geographic…

The contribution of geomorphological research to environmental issues in Mexico

Directory of Open Access Journals (Sweden)

Gerardo Bocco

2013-07-01

Full Text Available The paper analyzes the development of Mexican geomorphology and specially its contribution to environmental issues. To this end, a thorough literature review was carried out; papers were differentiated according to the type of journal (Mexican and international. Special emphasis was placed on analyzing whether the interest on environment was derived from a well defined theoretical framework, in particular in terms of the insertion of geomorphology in the geographic arena in Mexico. The review has focused on secientific papers duly refereed and available at the Internet. Thus other research was not included. However, that the database described in this paper represents a solid sample of the entire universe of the efforts of Mexican geomorphologists.

[Managing the discharge of diabetic patients from the emergency department: a consensus paper].

Science.gov (United States)

Cuervo Pinto, Rafael; Álvarez-Rodríguez, Esther; González Pérez de Villar, Noemí; Artola-Menéndez, Sara; Girbés Borrás, Juan; Mata-Cases, Manel; Galindo Rubio, Mercedes; Puig Larrosa, Juan; Muñoz Albert, Ricardo; Díaz Pérez, José Ángel

2017-10-01

Eighty to 90% of patients attended in emergency departments are discharged to home. Emergency department physicians are therefore responsible for specifying how these patients are treated afterwards. An estimated 30% to 40% of emergency patients have diabetes mellitus that was often decompensated or poorly controlled prior to the emergency. It is therefore necessary to establish antidiabetic treatment protocols that contribute to adequate metabolic control for these patients in the interest of improving the short-term prognosis after discharge. The protocols should also maintain continuity of outpatient care from other specialists and contribute to improving the long-term prognosis. This consensus paper presents the consensus of experts from 3 medical associations whose members are directly involved with treating patients with diabetes. The aim of the paper is to facilitate the assessment of antidiabetic treatment when the patient is discharged from the emergency department and referred to outpatient care teams.

Inkjet Printing of Paper-Based Wideband and High Gain Antennas

KAUST Repository

Cook, Benjamin

2011-12-07

This thesis represents a major contribution to wideband and high gain inkjet-printed antennas on paper. This work includes the complete characterization of the inkjet printing process for passive microwave devices on paper substrate as well as several ultra-wideband and high gain antenna designs. The characterization work includes the electrical characterization of the permittivity and loss tangent for paper substrate through 10 GHz, ink conductivity data for variable sintering conditions, and minimum feature sizes obtainable by today’s current inkjet processes for metallic nanoparticles. For the first time ever, inkjet-printed antennas are demonstrated that operate over the entire UWB band and demonstrate gains up to 8dB. This work also presents the first fractal-based inkjet-printed antennas with enhanced bandwidth and reduced production costs, and a novel slow wave log periodic dipole array which shows minimizations of 20% in width over conventional log periodic antennas.

Global Manufacturing Research: Experience Exchange Group (EEG) contributions

DEFF Research Database (Denmark)

Bruun, Peter

1998-01-01

of preliminary studies found interesting to set upan EEG composed of representatives from industry and a researcher. Inthe paper some general research methods pertinent to the areaindustrial management is discussed. The EEG concept is introduced andcharacterised in comparison with the other methods. EEG...... activities aredescribed and a tentative coupling to the phases in a research processis proposed. Following this is a discussion of methodological andquality requirements. It is considered how EEG activities couldpossible contribute to an industrial rooted research. The paper endsup looking at future research......The intention of this paper is to clarify if and how an ExperienceExchange Group (EEG) can be involved in a research process in the areaof industrial management. For exemplification of the topic an ongoingresearch in global manufacturing is referred to. In this research itwas after a series...

26 CFR 1.162-19 - Capital contributions to Federal National Mortgage Association.

Science.gov (United States)

2010-04-01

... issuance price (the amount of capital contributions evidenced by a share of stock) over the fair market... sale to FNMA of mortgage paper gives rise to the issuance of a share of FNMA stock during a taxable... gain or loss from the sale to FNMA of mortgage paper, with respect to which a share of FNMA stock is...

Moon over Mauna Loa - a review of hypotheses of formation of earth's moon

International Nuclear Information System (INIS)

Wood, J.A.

1986-01-01

The present paper examines five models of lunar formation after considering the following constraints: (1) the large mass of the moon and the substantial prograde angular momentum of the earth-moon system; (2) the moon's depletion in volatile elements and iron, (3) the correspondence of oxygen isotope signatures in earth and moon, and (4) the lunar magma ocean. The models considered are: (1) capture from an independent heliocentric orbit, (2) coaccretion from a swarm of planetesimals in geocentric orbit, (3) fission from a rapidly rotating earth, (4) collisional ejection, and (5) disintegrative capture. 99 references

BRAND POLICY INSTRUMENTS:CONTRIBUTIONS TO BRANDEQUITY

OpenAIRE

Roxana Dumitriu

2013-01-01

In this paper we attempted to establish the contributions of brand elements to the brand equity. Building brand equity is realized and is based on a series of visible elements, easy to recognize and to remember by the public. A name, a symbol, a slogan are just a part of the visible elements of the brand meaning. The brand elements are a shortcut of clients’ perception regarding the brand utility and brand image, suggesting some benefices of performance and competence. The brand elements that...

Ten Rules for Dealing with Negative Contributions in Social Media

OpenAIRE

Adriana Stránská; Václav Stříteský

2015-01-01

Social media is becoming a key part of business communication strategy. Despite all the advantages, social media also poses a threat to business reputation. Dissatisfied customers can reach a large audience and share their negative experiences with others. This paper deals with the impact of social media on the practice of public relations. The goal of the paper is to formulate a set of rules for dealing with negative contributions and generally with crisis communication in social media. It...

CONTRIBUTIONS ON THE DESIGN OF UNCONVENTIONAL CORRUGATED BOARD STRUCTURES

Directory of Open Access Journals (Sweden)

NEIDONI Nadina

2015-06-01

Full Text Available The paper depicts a few contributions on the design of several unconventional corrugated board structures. In general, cardboard and corrugated cardboard is strongly linked to packaging. However, limiting these materials to their primary use does nothing else but to restrict the possibilities of using them in other interesting areas. Consequently, new structures built from cardboard have been imagined and in the paper there are presented a few unconventional uses of the corrugated fiberboard, namely as furniture elements, along with the technology used in the design and the manufacturing process.

Asian-Pacific Papers. Occasional Papers Number 10.

Science.gov (United States)

McCarthy, Brian, Ed.

Sixteen papers are presented. Topics covered include language teaching, discourse analysis, code switching, phonetics, language and cultural identity, and descriptive and comparative studies. All presenters were from the Asia-Pacific area of the world. Papers include: "The Baba Malay Lexicon: Hokkien Loanwords in Baba Malay" (Anne…

Human Resource Development's Contribution to Continuous Improvement

DEFF Research Database (Denmark)

Jørgensen, Frances; Hyland, Paul

2007-01-01

Continuous Improvement (CI) is an approach to organizational change that requires active involvement of skilled and motivated employees, which implies an important role for HRD practitioners. The findings from a literature review and a survey of 168 Danish manufacturing companies indicate however...... that HRD is rarely integrated with CI. The paper contributes by offering a model that depicts how HR and HRD functions could be exploited to support successful CI development and implementation....

Computer Vision and Image Processing: A Paper Review

Directory of Open Access Journals (Sweden)

victor - wiley

2018-02-01

Full Text Available Computer vision has been studied from many persective. It expands from raw data recording into techniques and ideas combining digital image processing, pattern recognition, machine learning and computer graphics. The wide usage has attracted many scholars to integrate with many disciplines and fields. This paper provide a survey of the recent technologies and theoretical concept explaining the development of computer vision especially related to image processing using different areas of their field application. Computer vision helps scholars to analyze images and video to obtain necessary information,    understand information on events or descriptions, and scenic pattern. It used method of multi-range application domain with massive data analysis. This paper provides contribution of recent development on reviews related to computer vision, image processing, and their related studies. We categorized the computer vision mainstream into four group e.g., image processing, object recognition, and machine learning. We also provide brief explanation on the up-to-date information about the techniques and their performance.

The top 100 classic papers in lumbar spine surgery.

Science.gov (United States)

Steinberger, Jeremy; Skovrlj, Branko; Caridi, John M; Cho, Samuel K

2015-05-15

Bibliometric review of the literature. To analyze and quantify the most frequently cited papers in lumbar spine surgery and to measure their impact on the entire lumbar spine literature. Lumbar spine surgery is a dynamic and complex field. Basic science and clinical research remain paramount in understanding and advancing the field. While new literature is published at increasing rates, few studies make long-lasting impacts. The Thomson Reuters Web of Knowledge was searched for citations of all papers relevant to lumbar spine surgery. The number of citations, authorship, year of publication, journal of publication, country of publication, and institution were recorded for each paper. The most cited paper was found to be the classic paper from 1990 by Boden et al that described magnetic resonance imaging findings in individuals without back pain, sciatica, and neurogenic claudication showing that spinal stenosis and herniated discs can be incidentally found when scanning patients. The second most cited study similarly showed that asymptomatic patients who underwent lumbar spine magnetic resonance imaging frequently had lumbar pathology. The third most cited paper was the 2000 publication of Fairbank and Pynsent reviewing the Oswestry Disability Index, the outcome-measure questionnaire most commonly used to evaluate low back pain. The majority of the papers originate in the United States (n=58), and most were published in Spine (n=63). Most papers were published in the 1990s (n=49), and the 3 most common topics were low back pain, biomechanics, and disc degeneration. This report identifies the top 100 papers in lumbar spine surgery and acknowledges those individuals who have contributed the most to the advancement of the study of the lumbar spine and the body of knowledge used to guide evidence-based clinical decision making in lumbar spine surgery today. 3.

Contributions of Transonic Dynamics Tunnel Testing to Airplane Flutter Clearance

Science.gov (United States)

Rivera, Jose A.; Florance, James R.

2000-01-01

The Transonic Dynamics Tunnel (TDT) became in operational in 1960, and since that time has achieved the status of the world's premier wind tunnel for testing large in aeroelastically scaled models at transonic speeds. The facility has many features that contribute to its uniqueness for aeroelastic testing. This paper will briefly describe these capabilities and features, and their relevance to aeroelastic testing. Contributions to specific airplane configurations and highlights from the flutter tests performed in the TDT aimed at investigating the aeroelastic characteristics of these configurations are presented.

Optional contributions have positive effects for volunteering public goods games

Science.gov (United States)

Song, Qi-Qing; Li, Zhen-Peng; Fu, Chang-He; Wang, Lai-Sheng

2011-11-01

Public goods (PG) games with the volunteering mechanism are referred to as volunteering public goods (VPG) games, in which loners are introduced to the PG games, and a loner obtains a constant payoff but not participating the game. Considering that small contributions may have positive effects to encourage more players with bounded rationality to contribute, this paper introduces optional contributions (high value or low value) to these typical VPG games-a cooperator can contribute a high or low payoff to the public pools. With the low contribution, the logit dynamics show that cooperation can be promoted in a well mixed population comparing to the typical VPG games, furthermore, as the multiplication factor is greater than a threshold, the average payoff of the population is also enhanced. In spatial VPG games, we introduce a new adjusting mechanism that is an approximation to best response. Some results in agreement with the prediction of the logit dynamics are found. These simulation results reveal that for VPG games the option of low contributions may be a better method to stimulate the growth of cooperation frequency and the average payoff of the population.

U.S. Contributions to ITER

International Nuclear Information System (INIS)

Sauthoff, Ned R.

2005-01-01

The United States participates in the ITER project and program to enable the study of the science and technology of burning plasmas, a key programmatic element missing from the world fusion program. The 2003 U.S. decision to enter the ITER negotiations followed an extensive series of community and governmental reviews of the benefits, readiness, and approaches to the study of burning plasmas. This paper describes both the technical and the organizational preparations and plans for U.S. participation in the ITER construction activity: in-kind contributions, staff contributions, and cash contributions as well as supporting physics and technology research. Near-term technical activities focus on the completion of R and D and design and mitigation of risks in the areas of the central solenoid magnet, shield/blanket, diagnostics, ion cyclotron system, electron cyclotron system, pellet fueling system, vacuum system, tritium processing system, and conventional systems. Outside the project, the U .S. is engaged in preparations for the test blanket module program. Organizational activities focus on preparations of the project management arrangements to maximize the overall success of the ITER Project; elements include refinement of U.S. directions on the international arrangements, the establishment of the U.S. Domestic Agency, progress along the path of the U.S. Department of Energy's Project Management Order, and overall preparations for commencement of the fabrication of major items of equipment and for provision of staff and cash as specified in the upcoming ITER agreement

Paper-based assay of antioxidant activity using analyte-mediated on-paper nucleation of gold nanoparticles as colorimetric probes.

Science.gov (United States)

Choleva, Tatiana G; Kappi, Foteini A; Giokas, Dimosthenis L; Vlessidis, Athanasios G

2015-02-20

With the increasing interest in the health benefits arising from the consumption of dietary products rich in antioxidants, there exists a clear demand for easy-to-use and cost-effective tests that can be used for the identification of the antioxidant power of food products. Paper-based analytical devices constitute a remarkable platform for such expedient and low-cost assays with minimal external resources but efforts in this direction are still scarce. In this work we introduce a new paper-based device in the form of a sensor patch that enables the determination of antioxidant activity through analyte-driven on-paper formation of gold nanoparticles. The principle of detection capitalizes, for the first time, on the on-paper nucleation of gold ions to its respective nanoparticles, upon reduction by antioxidant compounds present in an aqueous sample. The ensuing chromatic transitions, induced on the paper surface, are used as an optical "signature" of the antioxidant strength of the solution. The response of the paper-based sensor was evaluated against a large variety of antioxidant species and the respective dose response curves were constructed. On the basis of these data, the contribution of each species according to its chemical structure was elucidated. For the analysis of real samples, a concentration-dependent colorimetric response was established against Gallic acid equivalents over a linear range of 10 μM-1.0 mM, with detection limits at the low and ultra-low μM levels (i.e. <1.0 μM) and satisfactory precision (RSD=3.6-12.6%). The sensor has been tested for the assessment of antioxidant activity in real samples (teas and wines) and the results correlated well with commonly used antioxidant detection methods. Importantly, the sensor performed favorably for long periods of time when stored at moisture-free and low temperature conditions without losing its activity thus posing as an attractive alternative to the assessment of antioxidant activity without

The willingness of professionals to contribute to their organisation's certification

NARCIS (Netherlands)

dr. H. de Vries; prof.dr.ing. T.W. Hardjono; PhD Everard van Kemenade

2011-01-01

Research has shown that it is difficult to motivate professionals to contribute to certification. Little research has been done on the reasons why. The paper provides more insight into the difficulties that organizations face to commit their professionals to become involved in certification and

Microsurgery: the top 50 classic papers in plastic surgery: a citation analysis.

Science.gov (United States)

Joyce, Cormac Weekes; Carroll, Sean Michael

2014-03-01

The number of citations that a published article has received reflects the importance of the paper in the particular area of practice. In microsurgery, thus far, which journal articles are cited most frequently is unknown. The purpose of this study was to identify and analyze the characteristics of the top 50 papers in the field of microsurgery in the plastic surgery literature. The 50 most cited papers published in high impact plastic surgery and microsurgery journals were identified. The articles were ranked in the order of the number of citations received. These 50 classic papers were analyzed for article type, journal distribution, and geographic and institutional origin. Six international journals contributed to the top 50 papers in microsurgery. The most cited paper reported on the early use of the vascularized bone graft and was cited 116 times. The top 50 papers originated from just 10 countries with the United States producing the most. The Preston and Northcote Community Hospital, Melbourne published 5 papers and this was the most productive institution in the top 50. These papers represent many important milestones in the relatively short history of microsurgery. Furthermore, our citation analysis provides useful information to budding authors as to what makes a paper attain a "classic" status.

Ettore Majorana, Scientific Papers Festschrift for his 100th Birthday

CERN Document Server

2006-01-01

With this volume the Italian Physical Society presents a collection of Ettore Majorana's scientific papers (note scientifiche) in the original language and, for the first time - with three exceptions - translated into English. Each paper is then followed by a comment (in English) of an expert in the scientific field. Contributors to the comments are Ennio Arimondo, Nicola Cabibbo, Massimo Inguscio, Luciano Maiani, Rosario Nunzio Mantegna, Francesco Minardi, Luigi Radicati di Brozolo and Antonio Sasso. A century after his birth Ettore Majorana is rightfully considered one of the greatest physicists of the first half of the last century. This volume will be of interest to the specialists of the History of Science and to the physicists concerned with problems related to Majorana's contributions

Twelfth European TRIGA users conference. Papers and abstracts

International Nuclear Information System (INIS)

2008-01-01

The Twelfth European TRIGA Users Conference was held in Pitesti, Romania, on September 28 - October 1, 1992, under the sponsorship of the Institute for Nuclear Research. The papers which follow in this document are presented in the same order as listed in the Conference Program. All papers which were received for publication (44) have been included. Those papers which were presented but not received for publication are presented in abstract form (3). The European TRIGA9 Owners' Group was fortunate to be hosted by the owners and users of the world's largest TRIGA reactor - the 14-MW Romanian research and test reactor. For too many years it has been impossible to enjoy open interactions with the Romanian researchers. By hosting the 1992 European TRIGA Users' Conference in Romania, the Romanians accomplished a breakthrough in the exchange of TRIGA reactor technology. It was very interesting for the Conference attendees from the West to learn about the large scope of excellent work conducted in Romania, especially at the Institute of Nuclear Research in Pitesti. Similarly, it was fortunate that a large attendance of Romanian researchers from many institutes, universities, and government agencies could attend the Conference and interact with their counterparts from outside Romania. The proceedings of the conference were structured onto the following 6 subject matters: - Opening Session and Introduction; - Session I, Operating and Maintenance Experience (10 papers); - Session II, Reactor Physics And Fuel Utilization (11 papers); - Session III, Instrumentation and Control (5 papers); - Session IV, Irradiation Facilities, Experimental Accessories (8 papers); - Session V, Applications, New Development of TRIGA Concept (6 papers). The document is completed with the abstracts of 3 contributions. A number of 19 experts from Austria, Germany, Italy, United States, Turkey, Morocco, England, Slovenia and Albania, that use TRIGA reactors, and Romania attended the conference. The

The design paradox: the contribution of in-house and external design activities on product market performance

OpenAIRE

Czarnitzki, Dirk; Thorwarth, Susanne

2009-01-01

This paper explores the contribution of design activities on product market performance of Belgian companies. While there is mounting evidence that design can be seen as a strategic tool to successfully spur sales of new product developments at the firm level, the topic of design innovation has not been linked to the open innovation concept yet. In this paper we empirically test whether design activities conducted in-house differ in their contribution to new product sales from externally acqu...

Position Paper: Designing Complex Systems to Support Interdisciplinary Cognitive Work

Science.gov (United States)

Greene, Melissa T.; Papalambros, Panos Y.; Mcgowan, Anna-Maria R.

2016-01-01

The paper argues that the field we can call cognitive science of interdisciplinary collaboration is an important area of study for improving design of Large-Scale Complex Systems (LaCES) and supporting cognitive work. The paper mostly raised questions that have been documented in earlier qualitative analysis studies, and provided possible avenues of exploration for addressing them. There are likely further contributions from additional disciplines beyond those mentioned in this paper that should be considered and integrated into such a cognitive science framework. Knowledge and awareness of various perspectives will help to inform the types of interventions available for improving LaCES design and functionality. For example, a cognitive interpretation of interdisciplinary collaborations in LaCES elucidated the need for a "translator" or "mediator" in helping subject matter experts to transcend language boundaries, mitigate single discipline bias, support integrative activities, and correct misaligned objectives. Additional research in this direction is likely to uncover similar gaps and opportunities for improvements in practice.

QED contributions to electron g-2

Science.gov (United States)

Laporta, Stefano

2018-05-01

In this paper I briefly describe the results of the numerical evaluation of the mass-independent 4-loop contribution to the electron g-2 in QED with 1100 digits of precision. In particular I also show the semi-analytical fit to the numerical value, which contains harmonic polylogarithms of eiπ/3, e2iπ/3 and eiπ/2 one-dimensional integrals of products of complete elliptic integrals and six finite parts of master integrals, evaluated up to 4800 digits. I give also some information about the methods and the program used.

29 CFR 570.63 - Occupations involved in the operation of paper-products machines, scrap paper balers, and paper...

Science.gov (United States)

2010-07-01

... 29 Labor 3 2010-07-01 2010-07-01 false Occupations involved in the operation of paper-products machines, scrap paper balers, and paper box compactors (Order 12). 570.63 Section 570.63 Labor Regulations... involved in the operation of paper-products machines, scrap paper balers, and paper box compactors (Order...

Report on survey of contribution to foreign journals among the Japanese nuclear scientists and engineers

International Nuclear Information System (INIS)

Habu, Takeshi; Hiramatsu, Nobuaki; Ebinuma, Yukio

1981-01-01

Questionnaires were collected from 350 persons among the Japanese Nuclear Scientists and Engineers who had written their papers in English for contribution to foreign journals. These were analyzed on reasons for contribution to foreign journals, citation, publication charge, number of reprints and their distribution, career languages in usual writing, coauthorship and number and title names of journals to contribute. The contributions are mainly made for international dissemination and authority of the specific journals, and its tendency seems to be unchangeable. (author)

Supplier Contribution to Profit Calculation and Supplier’s Expense Levels

Directory of Open Access Journals (Sweden)

Danilo Dorović

2015-05-01

Full Text Available Suppliers of goods present a very important cost object for trading companiessuch as retail. There is, however, no theoretical explanation as to how to calculate a contribution to profits generated from an individual supplier. This calculation is the subject of the paper. There is no calculation that shows how goods, provided from the supplier, create profit through gross margin and how the supplier`s behavior influences the costs (like delivery terms, costs of keeping specific goods fresh…. The final costs further decrease the profit generated by suppliers. As they have long found it illogical to calculate contribution to profit from suppliers in a production company, trading companies have long ignored it, as well. The Activity Based Costing (ABC, as the up-to-date system, still does not possess the cost hierarchy for suppliers as the cost object. The aim of the paper is to present a proposal for creating the cost hierarchy for suppliers in a trade company through creating a theoretical financial model as a method. The model also offers a theoretical explanation of how to calculate the contribution from a supplier or a group of suppliers. It is based on empirically evident activities in any supermarket or hypermarket, which makes it possible to create explanatory theoretical research.

Contributions of the Ruksherbarium towards the plant-geography of Malesia and the Pacific

NARCIS (Netherlands)

Balgooy, van M.M.J.

1979-01-01

The first substantial contribution of the Rijksherbarium towards the plant geography of Malesia and the Pacific was made by the German born J. G. Hallier in his paper ‘Über frühere Landbrücken, Pflanzen- und Völkerwanderungen zwischen Australien und Amerika’. In this paper he suggested that recent

Optimization of paper machine heat recovery system; Paperikoneen laemmoentalteenottosysteemin optimointi - PMSY 02

Energy Technology Data Exchange (ETDEWEB)

Pettersson, H. [Valmet Oyj Pansio, Turku (Finland)

1998-12-31

Conventionally the energy content of paper and board machine dryer section exhaust air is recovered in the heat recovery tower. This has had a major contribution to the overall energy economy of a paper machine. Modern paper machines have already reached momentary record speeds above 1700 m/min, and speeds above 2000 m/min will be strived to. This is possible by developing new efficient drying technologies. These will require new solutions for the heat recovery systems. At the same time requirements for new heat recovery solutions come from the gradually closing of paper mill water circulation systems. In this project a discrete tool based on optimization is developed, a tool for analyzing, optimizing and dimensioning of paper machine heat recovery systems for different process conditions. Delivery of a paper machine process requires more and more transferring of process knowledge into calculation model parameters. The overall target of the tool is to decrease the energy consumption considering new drying technologies and the gradually closing of water circulation systems. (orig.)

Optimization of paper machine heat recovery system; Paperikoneen laemmoentalteenottosysteemin optimointi - PMSY 02

Energy Technology Data Exchange (ETDEWEB)

Pettersson, H [Valmet Oyj Pansio, Turku (Finland)

1999-12-31

Conventionally the energy content of paper and board machine dryer section exhaust air is recovered in the heat recovery tower. This has had a major contribution to the overall energy economy of a paper machine. Modern paper machines have already reached momentary record speeds above 1700 m/min, and speeds above 2000 m/min will be strived to. This is possible by developing new efficient drying technologies. These will require new solutions for the heat recovery systems. At the same time requirements for new heat recovery solutions come from the gradually closing of paper mill water circulation systems. In this project a discrete tool based on optimization is developed, a tool for analyzing, optimizing and dimensioning of paper machine heat recovery systems for different process conditions. Delivery of a paper machine process requires more and more transferring of process knowledge into calculation model parameters. The overall target of the tool is to decrease the energy consumption considering new drying technologies and the gradually closing of water circulation systems. (orig.)

Application of spectroscopic techniques for the study of paper documents: A survey

International Nuclear Information System (INIS)

Manso, M.; Carvalho, M.L.

2009-01-01

For many centuries paper was the main material for recording cultural achievements all over the world. Paper is mostly made from cellulose with small amounts of organic and inorganic additives, which allow its identification and characterization and may also contribute to its degradation. Prior to 1850, paper was made entirely from rags, using hemp, flax and cotton fibres. After this period, due to the enormous increase in demand, wood pulp began to be commonly used as raw material, resulting in rapid degradation of paper. Spectroscopic techniques represent one of the most powerful tools to investigate the constituents of paper documents in order to establish its identification and its state of degradation. This review describes the application of selected spectroscopic techniques used for paper characterization and conservation. The spectroscopic techniques that have been used and will be reviewed include: Fourier-Transform Infrared spectroscopy, Raman spectroscopy, Nuclear Magnetic Resonance spectroscopy, X-Ray spectroscopy, Laser-based Spectroscopy, Inductively Coupled Mass Spectroscopy, Laser ablation, Atomic Absorption Spectroscopy and X-Ray Photoelectron Spectroscopy.

Contribution to the WWER-440 Gd-assembly evolution

International Nuclear Information System (INIS)

Cudrnak, P.; Darilek, P.; Necas, V.

2009-01-01

Development activities, presented in the paper, contribute to the evolution of gadolinium fuel for the WWER-440 reactors. Short overview of existing and already proposed Gd-assemblies is given. Two new assembly types with improved features are described. Multiplication coefficients and pin power peaking factors of all mentioned gadolinium assemblies are compared. Animations of power distribution behaviour in selected Gd-assemblies are shown. (Authors)

The Contribution of Islamic Ethics Towards Ethical Accounting Practices

Directory of Open Access Journals (Sweden)

Rochania Ayu Yunanda

2011-12-01

and also increase public confidence in the profession. However, the efforts to integrate ethical values in educational system will not work well if there are no moral commitments implanted in the individuals.  Islam with its divine values plays the notable role to embed cognitive ethical values. It emphasizes on the unity of God, the accountability to God and the concept of maslahah (public benefits to be the foundations of ethics. Incorporating Islamic ethics into the system will be a significant contribution towards generating ethical accounting education. This paper attempts to elucidate how the Islamic ethics contribute its role towards ethical accountants as the products of accounting education.

Factors contributing to registered nurse medication administration error: a narrative review.

Science.gov (United States)

Parry, Angela M; Barriball, K Louise; While, Alison E

2015-01-01

To explore the factors contributing to Registered Nurse medication administration error behaviour. A narrative review. Electronic databases (Cochrane, CINAHL, MEDLINE, BNI, EmBase, and PsycINFO) were searched from 1 January 1999 to 31 December 2012 in the English language. 1127 papers were identified and 26 papers were included in the review. Data were extracted by one reviewer and checked by a second reviewer. A thematic analysis and narrative synthesis of the factors contributing to Registered Nurses' medication administration behaviour. Bandura's (1986) theory of reciprocal determinism was used as an organising framework. This theory proposes that there is a reciprocal interplay between the environment, the person and their behaviour. Medication administration error is an outcome of RN behaviour. The 26 papers reported studies conducted in 4 continents across 11 countries predominantly in North America and Europe, with one multi-national study incorporating 27 countries. Within both the environment and person domain of the reciprocal determinism framework, a number of factors emerged as influencing Registered Nurse medication administration error behaviour. Within the environment domain, two key themes of clinical workload and work setting emerged, and within the person domain the Registered Nurses' characteristics and their lived experience of work emerged as themes. Overall, greater attention has been given to the contribution of the environment domain rather than the person domain as contributing to error, with the literature viewing an error as an event rather than the outcome of behaviour. The interplay between factors that influence behaviour were poorly accounted for within the selected studies. It is proposed that a shift away from error as an event to a focus on the relationships between the person, the environment and Registered Nurse medication administration behaviour is needed to better understand medication administration error. Copyright © 2014

Contribution of timber exports to economic growth in Nigeria: an ...

African Journals Online (AJOL)

The paper examined the contribution of timber exports to the economic growth in Nigeria, using an econometric approach. Augmented Dickey-Fuller (ADF) and Johansen Co-integration techniques were respectively used to test for unit root and examine the relationship between the variables used. In addition, Granger ...

Humidity Sensors Printed on Recycled Paper and Cardboard

Directory of Open Access Journals (Sweden)

Matija Mraović

2014-07-01

Full Text Available Research, design, fabrication and results of various screen printed capacitive humidity sensors is presented in this paper. Two types of capacitive humidity sensors have been designed and fabricated via screen printing on recycled paper and cardboard, obtained from the regional paper and cardboard industry. As printing ink, commercially available silver nanoparticle-based conductive ink was used. A considerable amount of work has been devoted to the humidity measurement methods using paper as a dielectric material. Performances of different structures have been tested in a humidity chamber. Relative humidity in the chamber was varied in the range of 35%–80% relative humidity (RH at a constant temperature of 23 °C. Parameters of interest were capacitance and conductance of each sensor material, as well as long term behaviour. Process reversibility has also been considered. The results obtained show a mainly logarithmic response of the paper sensors, with the only exception being cardboard-based sensors. Recycled paper-based sensors exhibit a change in value of three orders of magnitude, whereas cardboard-based sensors have a change in value of few 10s over the entire scope of relative humidity range (RH 35%–90%. Two different types of capacitor sensors have been investigated: lateral (comb type sensors and modified, perforated flat plate type sensors. The objective of the present work was to identify the most important factors affecting the material performances with humidity, and to contribute to the development of a sensor system supported with a Radio Frequency Identification (RFID chip directly on the material, for use in smart packaging applications. Therefore, the authors built a passive and a battery-supported wireless module based on SL900A smart sensory tag’s IC to achieve UHF-RFID functionality with data logging capability.

Tax Compliance and Social Security Contributions – The Case Of Slovenia

Directory of Open Access Journals (Sweden)

Tomaz LESNIK

2014-06-01

Full Text Available In this paper, we will examine the causes behind the higher level of compliance with social security contributions in comparison with other tax categories in the case of Slovenia. The results of econometric models suggest that the activities of the Tax Administration of the Republic of Slovenia, which were more stringently performed in the area of social security contributions in the most recent period, are an important – but not the only factor – behind the higher level of compliance in connection with social security contributions. At the same time, the decrease in tax compliance with other taxes (income tax, corporate income tax, and VAT did not essentially influence the higher level of compliance with social security contributions. The more consistent treatment of unpaid social security contributions as a criminal offence and the higher public awareness about the importance of paying social security contributions in the latest period are recognized as important factors which simultaneously constitute the main difference between social security contributions and other taxes. The higher level of public awareness about the benefits that result from public services financed with taxes is recognized as a possible way to more optimally collect taxes in Slovenia.

Reduced game property of the egalitarian non-k-averaged contribution value and the Shapley value

NARCIS (Netherlands)

Namekata, Tsuneyuki; Driessen, Theo; Namekata, T.

2000-01-01

The Egalitarian Non-k-Averaged Contribution (ENk AC-) value for TU-game represents the equal division of the surplus of the total profits, given that each player is already allocated his individual contribution specified by worths of coalitions of size k. This paper deals with the axiomatic

Audio Papers

DEFF Research Database (Denmark)

Groth, Sanne Krogh; Samson, Kristine

2016-01-01

With this special issue of Seismograf we are happy to present a new format of articles: Audio Papers. Audio papers resemble the regular essay or the academic text in that they deal with a certain topic of interest, but presented in the form of an audio production. The audio paper is an extension...

A research-based commentary on the EC Green Paper "Audit Policy: Lessons form the Crisis": Governance and independence

DEFF Research Database (Denmark)

Warming-Rasmussen, Bent; Quick, Reiner; Liempd, Dennis van

2011-01-01

In the wake of ehe financial crisis, the EU Commision has published a Green Paper on the future role of the audit function in Europe. The Green Paper lists a number of proposals for tighter rules for audits and auditors in order to contribute to stabilizing the financial system. The present article...... presents research contributions to the question whether the auditor is to continue to provide both audit and non-audit services (NAS) to an audit client. Research results show that this double function for the same audit client is a problem for stakeholders' confidence in auditor independence. The Green...

Do Employer Pension Contributions Reflect Employee Preferences? Evidence from a Retirement Savings Reform in Denmark

DEFF Research Database (Denmark)

Fadlon, Itzik; Laird, Jessica; Nielsen, Torben Heien

2016-01-01

This paper studies how firms set contributions to employer provided 401(k)-type pension plans. Using a reform that decreased the subsidy to contributions to capital pension accounts for Danish workers in the top income tax bracket, we provide strong evidence that employers' contributions are based...... on their employees' savings preferences. We find an immediate decrease in employer contributions to capital accounts, whose magnitude increased in the share of employees directly affected by the reform. This response was large relative to average employee responses within private IRA-type plans and was accompanied...... by a similar magnitude shift of employer contributions to annuity accounts....

Parallel Architectures for Planetary Exploration Requirements (PAPER)

Science.gov (United States)

Cezzar, Ruknet

1993-01-01

The project's main contributions have been in the area of student support. Throughout the project, at least one, in some cases two, undergraduate students have been supported. By working with the project, these students gained valuable knowledge involving the scientific research project, including the not-so-pleasant reporting requirements to the funding agencies. The other important contribution was towards the establishment of a graduate program in computer science at Hampton University. Primarily, the PAPER project has served as the main research basis in seeking funds from other agencies, such as the National Science Foundation, for establishing a research infrastructure in the department. In technical areas, especially in the first phase, we believe the trip to Jet Propulsion Laboratory, and gathering together all the pertinent information involving experimental computer architectures aimed for planetary explorations was very helpful. Indeed, if this effort is to be revived in the future due to congressional funding for planetary explorations, say an unmanned mission to Mars, our interim report will be an important starting point. In other technical areas, our simulator has pinpointed and highlighted several important performance issues related to the design of operating system kernels for MIMD machines. In particular, the critical issue of how the kernel itself will run in parallel on a multiple-processor system has been addressed through the various ready list organization and access policies. In the area of neural computing, our main contribution was an introductory tutorial package to familiarize the researchers at NASA with this new and promising field zone axes (20). Finally, we have introduced the notion of reversibility in programming systems which may find applications in various areas of space research.

Contributions of a Science Museum for the Initial Training

Directory of Open Access Journals (Sweden)

Azizi Manuel Tempesta

2017-04-01

Full Text Available In this paper we present some results obtained in a master’s research which aimed to evaluate what are the contributions that the acting as Physical monitor in a Science Museum has for the initial training and the beginning of the teaching career. Basing our analysis, we have adopted as theoretical assumptions the Teachers Knowledge and the Training Needs. We interviewed a group of ten teachers who played the function of Physics mediator in the Interdisciplinary Dynamic Museum (MUDI of the State University of Maringá, and submit to the Textual Analysis Discursive process. The results allowed us to realize that the contributions go beyond the expected, revealing the great potential of the Science museums of as an aid to initial training, contributing to the development of competencies and abilities that today is required of the teacher, and them providing experiences load which otherwise would not be reached.

The global contribution of energy consumption by product exports from China.

Science.gov (United States)

Tang, Erzi; Peng, Chong

2017-06-01

This paper presents a model to analyze the mechanism of the global contribution of energy usage by product exports. The theoretical analysis is based on the perspective that contribution estimates should be in relatively smaller sectors in which the production characteristics could be considered, such as the productivity distribution for each sector. Then, we constructed a method to measure the global contribution of energy usage. The simple method to estimate the global contribution is the percentage of goods export volume compared to the GDP as a multiple of total energy consumption, but this method underestimates the global contribution because it ignores the structure of energy consumption and product export in China. According to our measurement method and based on the theoretical analysis, we calculated the global contribution of energy consumption only by industrial manufactured product exports in a smaller sector per industry or manufacturing sector. The results indicated that approximately 42% of the total energy usage in the whole economy for China in 2013 was contributed to foreign regions. Along with the primary products and service export in China, the global contribution of energy consumption for China in 2013 by export was larger than 42% of the total energy usage.

Japan-U. S. seminar on magmatic contributions to hydrothermal systems

Energy Technology Data Exchange (ETDEWEB)

Muffler, L. (U. S. Geological Survey, CA (United States)); Hedenquist, J. (Geological Survey of Japan, Tsukuba (Japan)); Kesler, S. (University of Michigan, MI (United States)); Izawa, E. (Kyushu University, Fukuoka (Japan). Faculty of Engineering)

1992-08-31

A multidisciplinary Seminar on Magmatic Contributions to Hydrothermal Systems'' was held at Ebino and Kagoshima at Kyushu, November, 1991. The principal purpose of the Ebino/Kagoshima Seminar was to bring together a small group of individuals which have been conducting active research on magmatic contributions to hydrothermal systems. The Seminar focussed on the porphyry and epithermal ore environments because of the potential to relate these environments to active volcanic and geothermal systems. Disciplines included valcanology, volcanic gas geochemistry, water geochemistry, isotope geochemistry, geochemical modeling, experimental geochemistry, igneous petrology, geothermal geology, economic geology, fluid-inclusion study, geophysics, and physical modeling. This paper summarizes the outline and significance of the Seminar. It was pointed out that understanding magmatic contributions to hydrothermal systems would require augmented experimental investigations, numerical modeling, field studies, and drilling.

Contribution to the study of perturbed planetary and protoplanetary disks

International Nuclear Information System (INIS)

Charnoz, Sebastien

2000-01-01

We studied some dynamical and photometric aspects of perturbed planetary and protoplanetary disks. In the first part of this work, using simple numerical models, the thermodynamic evolution of a colliding planetesimal disk perturbed by a giant planet core was studied. As soon as a giant planet embryo (- 15 earth masses) appears, a heat transfer is triggered in the disk, increasing strongly random velocities over a few astronomical units. The long term evolution of this transitory mechanism was investigated as well as its dependence to the perturber's mass. This is a generic mechanism that may have played an important role during the accretion of both terrestrial and giant planet embryos. Consequences concerning the origin of the Asteroid Belt are discussed, as well as the effect of fragmentation that could not been considered, because of numerical limitations. The second part of this work is a photometric study of Saturn's F ring, that is perturbed by its two nearby shepherding satellites. A 300 images data set, obtained at CFH telescope, was used. We put in evidence the presence of some elongated structures in the F ring, which origin is still a matter of debate. By combining our data set with some other spatial telescope images, new accurate orbital solutions for the F ring were derived, yielding a new radius of 140060 Angstroms ±60 km, that is 150 km smaller than the orbit derived in 1980-81. This may be the sign that the F ring suffered an important radial re-structuration during the last twenty years, which possible cause is also discussed. (author) [fr

Does the EUA Institutional Evaluation Programme Contribute to Quality Improvement?

Science.gov (United States)

Tavares, Diana Amado; Rosa, Maria Joao; Amaral, Alberto

2010-01-01

Purpose: This paper aims to reflect on the relevance of the Institutional Evaluation Programme (IEP) of the European University Association (EUA) to universities' quality improvement. It aims to analyse IEP follow-up reports to determine whether the programme contributes to the development of a quality improvement culture.…

CanWEA Pan-Canadian wind integration study paper

Energy Technology Data Exchange (ETDEWEB)

Tremblay, Martin [GL Garrad Hassan Canada Inc, Ottawa, ON (Canada); Gardner, Paul [GL Garrad Hassan and Partners, Glasgow (United Kingdom); Price, Doug; Le, Don [GL Garrad Hassan America, San Diego, CA (United States)

2010-07-01

GL Garrad Hassan has been contracted by CanWEA to undertake a scoping study for a future Pan-Canadian Wide-Scale Wind Integration Study. The scoping study provides the methodology and the rationale on which the actual wind integration study and request for proposals will be based on. Major system operators and owners of each Canadian Province along with experts involved in major US wind integration studies have been consulted and contributed to the decisional process. This paper provides a summary of the factors considered in the study and outline the actual methodology that was adopted for the future Pan-Canadian wind integration study. (orig.)

Student Teachers' Distinctive Contributions to Research on Primary School Children's Beliefs about Knowledge and Knowing

Science.gov (United States)

Kershner, Ruth; Hargreaves, Linda

2012-01-01

Student teachers' research is usually valued more for its contribution to their professional learning than for its contribution to the research topic itself. This paper reports on a research collaboration with eight student primary teachers in England, intended to build on a previously established project investigating young children's…

Short paper: Distributed vehicular traffic congestion detection algorithm for urban environments

OpenAIRE

Milojevic, M.; Rakocevic, V.

2013-01-01

Vehicular traffic congestion is a well-known economic and social problem generating significant costs and safety challenges, and increasing pollution in the cities. Current intelligent transport systems and vehicular networking technologies rely heavily on the supporting network infrastructure which is still not widely available. This paper contributes towards the development of distributed and cooperative vehicular traffic congestion detection by proposing a new vehicle-to-vehicle (V2V) cong...

Renewable energy sources. European Commission papers; Energies renouvelables. Documents de la Commission Europeenne

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-05-01

The ''Directive on the Promotion of Electricity from Renewable Sources of Energy in the Internal Electricity Market'' was adopted in September 2001. Its purpose is to promote an increase in the contribution of renewable energy sources to electricity production in the internal market for electricity and to create a basis for a future Community framework. Energie-Cites provides in this document a summary of its opinion on the Green Paper and on Alterner II and gives a proposal for an Action Plan concerning the White Paper. (A.L.B.)

Contributing from the margins

DEFF Research Database (Denmark)

Chimirri, Niklas Alexander

empirical study, I focused on kindergarten children’s first-person perspectives on the electronic media technologies they deemed subjectively relevant for conducting everyday life in the practice of their kindergarten. The concept of the children’s perspectives opens possibilities for transcending...... of the practice researcher when engaging with her/his potential co-researchers and the investigated, socio-materially mediated practice. The paper will argue that making sense of first-person perspectives – here on conducting a life with media technologies – presupposes that the researcher conceptualizes him....../herself as a contributor to an investigated practice, as inextricably entangled with the conducts of life of the others in relation to the conditions in practice. Doing research in the kindergarten thus becomes a mutual and collective endeavor, to which pedagogues, parents, children, and the researcher contribute. Even...

The Contribution of Forests and Trees to Sustainable Diets

Directory of Open Access Journals (Sweden)

Danny Hunter

2013-11-01

Full Text Available With the growing demands from a population expected to reach 9 billion people by 2050, it is unclear how our current global food system will meet future food needs. Ensuring that all people have access to adequate and nutritious food produced in an environmentally and socio-culturally sustainable manner is one of the greatest challenges of our time. “Sustainable diets” have been proposed as a multidimensional framework to address the need for nutritious and adequate food in the context of the many challenges facing the world today: reducing poverty and hunger, improving environmental health, enhancing human well-being and health, and strengthening local food networks, sustainable livelihoods and cultural heritage. This paper examines the contribution of forests and trees to sustainable diets, covering among others, nutritional, cultural, environmental and provisioning aspects. The literature reviewed highlight major opportunities to strengthen the contribution of forest and tree foods to sustainable diets. However, several constraints need to be removed. They relate to: cultural aspects, sustainable use of non-wood forest products, organization of forest food provisioning, limited knowledge of forest food composition, challenges in adapting management of forests and trees to account for forest foods, and in integrating forest biodiversity into complex landscapes managed for multiple benefits. Finally, the paper identifies research gaps and makes recommendations to enhance the contribution of forest foods to sustainable diets through increased awareness and better integration of information and knowledge on nutritious forest foods into national nutrition strategies and programs.

Clinical Research Informatics Contributions from 2015.

Science.gov (United States)

Daniel, C; Choquet, R

2016-11-10

To summarize key contributions to current research in the field of Clinical Research Informatics (CRI) and to select best papers published in 2015. A bibliographic search using a combination of MeSH and free terms search over PubMed on Clinical Research Informatics (CRI) was performed followed by a double-blind review in order to select a list of candidate best papers to be then peer-reviewed by external reviewers. A consensus meeting between the two section editors and the editorial team was finally organized to conclude on the selection of best papers. Among the 579 returned papers published in the past year in the various areas of Clinical Research Informatics (CRI) - i) methods supporting clinical research, ii) data sharing and interoperability, iii) re-use of healthcare data for research, iv) patient recruitment and engagement, v) data privacy, security and regulatory issues and vi) policy and perspectives - the full review process selected four best papers. The first selected paper evaluates the capability of the Clinical Data Interchange Standards Consortium (CDISC) Operational Data Model (ODM) to support the representation of case report forms (in both the design stage and with patient level data) during a complete clinical study lifecycle. The second selected paper describes a prototype for secondary use of electronic health records data captured in non-standardized text. The third selected paper presents a privacy preserving electronic health record linkage tool and the last selected paper describes how big data use in US relies on access to health information governed by varying and often misunderstood legal requirements and ethical considerations. A major trend in the 2015 publications is the analysis of observational, "nonexperimental" information and the potential biases and confounding factors hidden in the data that will have to be carefully taken into account to validate new predictive models. In addiction, researchers have to understand

PaperBLAST: Text Mining Papers for Information about Homologs.

Science.gov (United States)

Price, Morgan N; Arkin, Adam P

2017-01-01

Large-scale genome sequencing has identified millions of protein-coding genes whose function is unknown. Many of these proteins are similar to characterized proteins from other organisms, but much of this information is missing from annotation databases and is hidden in the scientific literature. To make this information accessible, PaperBLAST uses EuropePMC to search the full text of scientific articles for references to genes. PaperBLAST also takes advantage of curated resources (Swiss-Prot, GeneRIF, and EcoCyc) that link protein sequences to scientific articles. PaperBLAST's database includes over 700,000 scientific articles that mention over 400,000 different proteins. Given a protein of interest, PaperBLAST quickly finds similar proteins that are discussed in the literature and presents snippets of text from relevant articles or from the curators. PaperBLAST is available at http://papers.genomics.lbl.gov/. IMPORTANCE With the recent explosion of genome sequencing data, there are now millions of uncharacterized proteins. If a scientist becomes interested in one of these proteins, it can be very difficult to find information as to its likely function. Often a protein whose sequence is similar, and which is likely to have a similar function, has been studied already, but this information is not available in any database. To help find articles about similar proteins, PaperBLAST searches the full text of scientific articles for protein identifiers or gene identifiers, and it links these articles to protein sequences. Then, given a protein of interest, it can quickly find similar proteins in its database by using standard software (BLAST), and it can show snippets of text from relevant papers. We hope that PaperBLAST will make it easier for biologists to predict proteins' functions.

Performers and performance : how to investigate the contribution of the operational network to operational performance

NARCIS (Netherlands)

Wijngaard, J.; Vries, J. de; Nauta, A.

2006-01-01

Purpose This paper seeks to explore the question of how to investigate the contribution of the operational network (comprising sales service, logistics, planning, production, etc.) to operational performance. In doing so, the paper aims to link concepts from organisational and social psychology to

Performers and performance : How to investigate the contribution of the operational network to operational performance

NARCIS (Netherlands)

Wijngaard, J.; de Vries, J.; Nauta, Aukje

2006-01-01

Purpose - This paper seeks to explore the question of how to investigate the contribution of the operational network (comprising sales service, logistics, planning, production, etc.) to operational performance. In doing so, the paper aims to link concepts from organisational and social psychology to

Advantages and contributions in the balanced scorecard implementation

Directory of Open Access Journals (Sweden)

Patrícia Quesado

2018-02-01

Full Text Available Purpose: In this paper we aim to identify and analyse a set of advantages and contributions derived from the Balanced Scorecard (BSC implementation. Design/methodology/approach: In order to answer the research question, we have carried out a qualitative research based on the exclusively bibliographical review of theoretical / conceptual and empirical works previously done on the subject (systematic review of the literature. Findings: The results allow us to conclude that the BSC is more than a simple performance evaluation system, to become a true strategic management tool able to clarify and translate the mission and organizational strategy, making possible the communication process, the strategic alignment and the organizational learning. Originality/value: The study presents a contribution to the current state of knowledge, since the identification of the advantages and contributions in the BSC introduction and implementation can facilitate its adoption and development in the organizations that intend to implement this tool. In addition, a theoretical basis is provided for subsequent research, evidencing the breadth of research on the topic studied.

Terahertz Absorption by Cellulose: Application to Ancient Paper Artifacts

Science.gov (United States)

Peccianti, M.; Fastampa, R.; Mosca Conte, A.; Pulci, O.; Violante, C.; Łojewska, J.; Clerici, M.; Morandotti, R.; Missori, M.

2017-06-01

Artifacts made of cellulose, such as ancient documents, pose a significant experimental challenge in the terahertz transmission spectra interpretation due to their small optical thickness. In this paper, we describe a method to recover the complex refractive index of cellulose fibers from the terahertz transmission data obtained on single freely standing paper sheets in the (0.2-3.5)-THz range. By using our technique, we eliminate Fabry-Perot effects and recover the absorption coefficient of the cellulose fibers. The obtained terahertz absorption spectra are explained in terms of absorption peaks of the cellulose crystalline phase superimposed to a background contribution due to a disordered hydrogen-bond network. The comparison between the experimental spectra with terahertz vibrational properties simulated by density-functional-theory calculations confirms this interpretation. In addition, evident changes in the terahertz absorption spectra are produced by natural and artificial aging on paper samples, whose final stage is characterized by a spectral profile with only two peaks at about 2.1 and 3.1 THz. These results can be used to provide a quantitative assessment of the state of preservation of cellulose artifacts.

ZEUS contributions to the Real-Time 93 conference, Vancouver, Canada

International Nuclear Information System (INIS)

1993-07-01

This is a collection of the eight contributions of the ZEUS Data Acquisition group, presented at the Eighth Conference on Real-Time Computer Applications in Nuclear, Particle and Plasma Physics, Vancouver, Canada, June 8-11, 1993. This note describes the major parts of the ZEUS Data Acquisition system and the experience gained since the first HERA running in April 1992. Note that the papers are appended in the order of recommended reading, which does not reflect the order of importance. The presenters for the papers are listed in the following. (orig.)

Geography and Powerful Knowledge: A Contribution to the Debate

Science.gov (United States)

Maude, Alaric

2018-01-01

This paper is a contribution to the debate on powerful knowledge in geography that began in a 2015 issue of IRGEE and was continued by Frances Slater and Norman Graves in 2016. It addresses some of the questions raised by Slater and Graves. First, it suggests an alternative way of describing and identifying powerful knowledge than the one in their…

A Nobel Prize for empirical macroeconometrics: assessing the contributions of Thomas Sargent and Christopher Sims

NARCIS (Netherlands)

Boumans, M.; Sent, E.M.

2013-01-01

This paper provides an assessment of the contributions of the 2011 Nobel Prize winners, Thomas Sargent and Christopher Sims. They received the prize ‘for their empirical research on cause and effect in the macroeconomy’. The paper illustrates that Sargent entertained different interpretations of

APT related papers presented at the 1997 particle accelerator conference, Vancouver, May 12--16, 1997

International Nuclear Information System (INIS)

Lawrence, G.

1997-07-01

Tritium is essential for the US nuclear weapons to function, but because it is radioactive with a half-life of 12.3 years, the supply must be periodically replenished. Presently, only reactor or accelerator systems can be used to produce tritium. This report is a compilation of 31 papers given at the 1997 Particle Accelerator Conference which dealt with the accelerator production of tritium. The papers are grouped into two categories, invited and contributed

APT related papers presented at the 1997 particle accelerator conference, Vancouver, May 12--16, 1997

Energy Technology Data Exchange (ETDEWEB)

Lawrence, G. [comp.

1997-07-01

Tritium is essential for the US nuclear weapons to function, but because it is radioactive with a half-life of 12.3 years, the supply must be periodically replenished. Presently, only reactor or accelerator systems can be used to produce tritium. This report is a compilation of 31 papers given at the 1997 Particle Accelerator Conference which dealt with the accelerator production of tritium. The papers are grouped into two categories, invited and contributed.

Consensus Paper: Language and the Cerebellum: an Ongoing Enigma

Science.gov (United States)

Mariën, Peter; Ackermann, Herman; Adamaszek, Michael; Barwood, Caroline H. S.; Beaton, Alan; Desmond, John; De Witte, Elke; Fawcett, Angela J.; Hertrich, Ingo; Küper, Michael; Leggio, Maria; Marvel, Cherie; Molinari, Marco; Murdoch, Bruce E.; Nicolson, Roderick I.; Schmahmann, Jeremy D.; Stoodley, Catherine J.; Thürling, Markus; Timmann, Dagmar; Wouters, Ellen; Ziegler, Wolfram

2014-01-01

In less than three decades, the concept “cerebellar neurocognition” has evolved from a mere afterthought to an entirely new and multifaceted area of neuroscientific research. A close interplay between three main strands of contemporary neuroscience induced a substantial modification of the traditional view of the cerebellum as a mere coordinator of autonomic and somatic motor functions. Indeed, the wealth of current evidence derived from detailed neuroanatomical investigations, functional neuroimaging studies with healthy subjects and patients and in-depth neuropsychological assessment of patients with cerebellar disorders shows that the cerebellum has a cardinal role to play in affective regulation, cognitive processing, and linguistic function. Although considerable progress has been made in models of cerebellar function, controversy remains regarding the exact role of the “linguistic cerebellum” in a broad variety of nonmotor language processes. This consensus paper brings together a range of different viewpoints and opinions regarding the contribution of the cerebellum to language function. Recent developments and insights in the nonmotor modulatory role of the cerebellum in language and some related disorders will be discussed. The role of the cerebellum in speech and language perception, in motor speech planning including apraxia of speech, in verbal working memory, in phonological and semantic verbal fluency, in syntax processing, in the dynamics of language production, in reading and in writing will be addressed. In addition, the functional topography of the linguistic cerebellum and the contribution of the deep nuclei to linguistic function will be briefly discussed. As such, a framework for debate and discussion will be offered in this consensus paper. PMID:24318484

Consensus paper: Language and the cerebellum: an ongoing enigma.

Science.gov (United States)

Mariën, Peter; Ackermann, Herman; Adamaszek, Michael; Barwood, Caroline H S; Beaton, Alan; Desmond, John; De Witte, Elke; Fawcett, Angela J; Hertrich, Ingo; Küper, Michael; Leggio, Maria; Marvel, Cherie; Molinari, Marco; Murdoch, Bruce E; Nicolson, Roderick I; Schmahmann, Jeremy D; Stoodley, Catherine J; Thürling, Markus; Timmann, Dagmar; Wouters, Ellen; Ziegler, Wolfram

2014-06-01

In less than three decades, the concept "cerebellar neurocognition" has evolved from a mere afterthought to an entirely new and multifaceted area of neuroscientific research. A close interplay between three main strands of contemporary neuroscience induced a substantial modification of the traditional view of the cerebellum as a mere coordinator of autonomic and somatic motor functions. Indeed, the wealth of current evidence derived from detailed neuroanatomical investigations, functional neuroimaging studies with healthy subjects and patients and in-depth neuropsychological assessment of patients with cerebellar disorders shows that the cerebellum has a cardinal role to play in affective regulation, cognitive processing, and linguistic function. Although considerable progress has been made in models of cerebellar function, controversy remains regarding the exact role of the "linguistic cerebellum" in a broad variety of nonmotor language processes. This consensus paper brings together a range of different viewpoints and opinions regarding the contribution of the cerebellum to language function. Recent developments and insights in the nonmotor modulatory role of the cerebellum in language and some related disorders will be discussed. The role of the cerebellum in speech and language perception, in motor speech planning including apraxia of speech, in verbal working memory, in phonological and semantic verbal fluency, in syntax processing, in the dynamics of language production, in reading and in writing will be addressed. In addition, the functional topography of the linguistic cerebellum and the contribution of the deep nuclei to linguistic function will be briefly discussed. As such, a framework for debate and discussion will be offered in this consensus paper.

Public libraries, as an infrastructure for a sustainable public sphere: A systematic review of research: A preliminary paper

DEFF Research Database (Denmark)

Audunson, Ragnar; Svandhild, Aabø,; Blomgren, Roger

of the major findings are: Research on libraries as public sphere institutions cover a wide range of topics the dominating being freedom of access to information, often related to social inclusion, empowerment and justice. Contributions are often normative and non-empirical, but the proportion of empirically...... based research is increasing. This paper focuses on contributions related to public libraries.......This paper is based on a systematic literature search aiming at identifying research on the role of libraries as institutions underpinning a sustainable public sphere in a digital age. The major research questions are: 1. Is systematic literature search a fruitful method when it comes to a social...

Contribution and influence of proceedings papers to citation impact in seven conference and journal-driven sub-fields of energy research 2005-11

DEFF Research Database (Denmark)

Ingwersen, Peter; Larsen, Birger; Garcia-Zorita, J. Carlos

2013-01-01

and Wave Energy, Geo-thermal, Bio-fuel and Bio-mass energy sub-fields. The analyses cover research and review articles as well as conference proceeding papers excluding meeting abstracts published 2005-09 and cited 2005-11 through Web of Science. Central findings are: The distribution across document types......This paper analyses the following seven sub-fields of Sustainable Energy Research with respect to the influence of conference paper dominance on citation patterns across citing and cited document types, overall sub-field and document type impacts and citedness: Wind Power, Renewable Energy, Solar...

Thermopressure hydrolysis. Paper; Thermodruckhydrolyse. Paper

Energy Technology Data Exchange (ETDEWEB)

Stahl, R. [Scheuchl GmbH, Ortenburg (Germany); Prechtl, S. [Applikations- und Technikzentrum fuer Energieverfahrens-, Umwelt- und Stroemungstechnik (ATZ-EVUS), Sulzbach-Rosenberg (Germany)

2000-12-01

This paper presents a processing method which consists in thermal hydrolysis and subsequent anaerobic fermentation and is especially well suited for wet, low-structure organic wastes. [German] Das vorgestellte Verwertungsverfahren bestehend aus thermischer Hydrolyse und anschliessender anaerober Vergaerung eignet sich besonders fuer nasse, strukturarme organische Abfaelle. (orig.)

The contribution of work representation to solving the governance structure problem

NARCIS (Netherlands)

Berg, A. van den

2004-01-01

The aim of this paper is to explain in what ways work representation may contribute to an efficient governance structure. The insights from institutional economic theories will be applied to two different kinds of employee participation, namely trade unions and works councils. From the discussion

Quality over Quantity: Contribution of Urban Green Space to Neighborhood Satisfaction

NARCIS (Netherlands)

Zhang, Yang; Berg, van den A. E.; van Dijk, Theodorus; Weitkamp, Gerd

2017-01-01

There is increasing evidence that the quality of green space significantly contributes to neighborhood satisfaction and well-being, independent of the mere amount of green space. In this paper, we examined residents' perceptions of the quality and beneficial affordances of green space in relation to

Contribution Index Based on Green Building Certification Systems

OpenAIRE

Yuting Sun; Bee Hua Goh

2015-01-01

Green Building Certification Systems (GBCS) are carried out in many countries due to the rising awareness of the importance of sustainability in the building industry. The intention should have motivated participants to construct and operate buildings sustainably, however, there is not yet a method developed to investigate the motivation of the participants. Based on the GBCS, this paper proposes the contribution index as a standard global method to analyze the performance of participants in ...

Exploring the contribution of formal and informal learning to academic staff member employability: A Dutch perspective

NARCIS (Netherlands)

Klink, Marcel; van der Heijden, Beatrice; Boon, Jo; van Rooij, Shahron Williams

2014-01-01

Purpose – Little attention has been paid to the employability of academic staff and the extent to which continuous learning contributes to academic career success. The purpose of this paper is to explore the contribution of formal and informal learning to employability. Design/methodology/approach –

Contributions to the theory of fission neutron emission

International Nuclear Information System (INIS)

Seeliger, D.; Maerten, H.; Ruben, A.

1990-03-01

This report gives a compilation of recent work performed at Technical University, Dresden by D. Seeliger, H. Maerten and A. Ruben on the topic of fission neutron emission. In the first paper calculated fission neutron spectra are presented using the temperature distribution model FINESSE for fissioning actinide nuclei. In the second paper, starting from a general energy balance, Terrell's approach is generalized to describe average fragment energies as a function of incident energy; trends of fragment energy data in the Th-Pu region are well reproduced. In the third contribution, prompt fission neutron spectra and fragment characteristics for spontaneous fission of even Pu-isotopes are presented and discussed in comparison with experimental data using a phenomenological scission point model including temperature dependent shell effects. In the fourth paper, neutron multiplicities and energy spectra as well as average fragment energies for incident energies from threshold to 20 MeV (including multiple-chance fission) for U-238 are compared with traditional data representations. (author). Refs, figs and tabs

The contribution of tourism industry on the GDP growth of Western Balkan countries

Directory of Open Access Journals (Sweden)

Čerović Slobodan

2015-01-01

Full Text Available Tourism industry records various economic, social, political and others influences and provides itself important position in the overall economic development of many countries. The analysis of the available data of tourist arrivals and number of tourist overnight stays in observed countries of the Western Balkans (Serbia, Macedonia, Montenegro led us to conduct research in order to determine tourism contribution to the overall economic growth. Based on the modified methodology used by Brida et al. (2008 for calculating real GDP growth rates and tourism contribution to the overall economic growth, the paper indicates that tourism makes a modest direct contribution to the overall economic growth in the examined countries, regardless of the continuous increase in the number of foreign tourist arrivals. The level of tourism contribution to the overall economic growth varies and it is primarily related to diversity and quality of supply (the highest contribution is recorded in Montenegro, while lowest contribution is observed in Macedonia.

Designing quality of care--contributions from parents: Parents' experiences of care processes in paediatric care and their contribution to improvements of the care process in collaboration with healthcare professionals.

Science.gov (United States)

Gustavsson, Susanne; Gremyr, Ida; Kenne Sarenmalm, Elisabeth

2016-03-01

The aim of this article was to explore whether current quality dimensions for health care services are sufficient to capture how parents perceive and contribute to quality of health care. New quality improvement initiatives that actively involve patients must be examined with a critical view on established quality dimensions to ensure that these measures support patient involvement. This paper used a qualitative and descriptive design. This paper is based on interviews with parents participating in two experience-based co-design projects in a Swedish hospital that included qualitative content analysis of data from 12 parent interviews in paediatric care. Health care professionals often overemphasize their own significance for value creation in care processes and underappreciate parents' ability to influence and contribute to better quality. However, quality is not based solely on how professionals accomplish their task, but is co-created by health care professionals and parents. Consequently, assessment of quality outcomes also must include parents' ability and context. This paper questions current models of quality dimensions in health care, and suggests additional sub-dimensions, such as family quality and involvement quality. This paper underscores the importance of involving parents in health care improvements with health care professionals to capture as many dimensions of quality as possible. © 2015 John Wiley & Sons Ltd.

A Student's Guide to Einstein's Major Papers

International Nuclear Information System (INIS)

Janssen, Michel

2013-01-01

The core of this volume is formed by four chapters (2–5) with detailed reconstructions of the arguments and derivations in four of Einstein's most important papers, the three main papers of his annus mirabilis 1905 (on the light quantum, Brownian motion, and special relativity) and his first systematic exposition of general relativity of 1916. The derivations are given in sufficient detail and in sufficiently modernized notation (without any serious distortion of the originals) for an undergraduate physics major to read and understand them with far less effort than it would take him or her to understand (English translations of) Einstein's original papers. Each of these four papers is accompanied by a detailed introduction, which covers the conceptual development of the relevant field prior to Einstein's contribution to it and corrects some of the myths surrounding these papers that still have not been fully eradicated among physicists. (One quibble: though Kennedy correctly points out that the goal of the light quantum paper was not to explain the photoelectric effect, it is also not quite right to say that 'it was written to explain the Wien region of blackbody radiation' (p. xv). Einstein used this explanatory feat as the central argument for his light quantum hypothesis.) These four chapters then are the most valuable part of the volume. They could be used, independently of one another, but preferably in conjunction with Einstein's original texts, in courses on quantum mechanics, statistical mechanics, electrodynamics, and general relativity, respectively, to add a historical component to such courses. As a historian of science embedded in a physics department who is regularly called upon to give guest lectures in such courses on the history of their subjects, I can highly recommend the volume for this purpose. However, I would not adopt this volume as (one of) the central text(s) for a course on the history of modern physics. For one thing, chapter 1, which

STIGLER’S INFLUENTIAL CONTRIBUTION TO ECONOMIC THOUGHT

Directory of Open Access Journals (Sweden)

Artidiatun Adji

2017-01-01

Full Text Available This paper analyzes George J. Stigler’s influential contributions to economic ideas, specifically on industrial structures, the functioning of markets, the causes and effects of public regulation, the economics of information, and on the development of economic thought. Stigler’s most influential contribution to economic thought came in his work on information theory. Treating information as a valuable commodity, he explained why prices differ for identical goods. From his work, many other theories have been built to explain economic behavior. A considerable number of works on decision making under uncertainty could not have progressed without an understanding of the role of information. His swing of the pendulum in economic regulation constitutes a great turnabout. He started research, known as public choice, which assumes that government policymakers are driven by self-interest rather than pure concern for the public’s welfare. His views have now become those of the mainstream.

Managing Nuclear Corporate Memories: Malaysia Contribution to INIS Development, 2010-2015

International Nuclear Information System (INIS)

Mohd Hafizal Yusof; Habibah Adnan

2016-01-01

International Nuclear Information System (INIS) has been developed since 1969 in cooperation between Member states under International Atomic Energy Agency (IAEA). This paper produced in aim to ensure that Malaysia also contribute into INIS development in acquiring, managing and disseminating nuclear related information within this countries. (author)

Control practices contribute to premature transformer failures

Energy Technology Data Exchange (ETDEWEB)

Jauch, E.T. [Beckwith Electric Company Inc., Largo, FL (United States)

2007-07-01

Studies of premature load tap changer (LTC) transformer failures on utility systems have shown the tap changers to be the primary contributing factor. Some of the LTC factors that lead to transformer failures include oil quality and particulate contamination; LTC contact temperature rise; contact coking; carbon film build-up; short circuit mechanical forces; and contact wear and arcing. These factors create increasing contact resistance thereby increasing voltage drop, localized heating, contact pitting, oil contamination and general deterioration. This paper discussed utility tapchanger control practices and methods of determining control functions to be activated as well as the determination of optimum settings contributing to excessive or untimely tap change operations. The transformer applications that were considered included transmission tie transformers as well as transmission distribution interface transformers. The paper discussed the circulating current paralleling method and the circulating reactive current or var sharing paralleling method. Several common practices were discussed, including basic voltage control ranges and setting effects; timing options available; LDC misapplications; first house protection methods; and various paralleling techniques. It was concluded that although there are several other methods of paralleling power transformers, many are not applicable under certain system configurations. In these applications, improper use of a paralleling method or improper setting and commissioning may cause hunting for appropriate tap positions and dramatically increase the number of tap changes, causing wear and degradation of the tap changer contacts. 3 refs., 5 figs.

Separating the contributions of variability and parameter uncertainty in probability distributions

International Nuclear Information System (INIS)

Sankararaman, S.; Mahadevan, S.

2013-01-01

This paper proposes a computational methodology to quantify the individual contributions of variability and distribution parameter uncertainty to the overall uncertainty in a random variable. Even if the distribution type is assumed to be known, sparse or imprecise data leads to uncertainty about the distribution parameters. If uncertain distribution parameters are represented using probability distributions, then the random variable can be represented using a family of probability distributions. The family of distributions concept has been used to obtain qualitative, graphical inference of the contributions of natural variability and distribution parameter uncertainty. The proposed methodology provides quantitative estimates of the contributions of the two types of uncertainty. Using variance-based global sensitivity analysis, the contributions of variability and distribution parameter uncertainty to the overall uncertainty are computed. The proposed method is developed at two different levels; first, at the level of a variable whose distribution parameters are uncertain, and second, at the level of a model output whose inputs have uncertain distribution parameters

Paper Capillary Enables Effective Sampling for Microfluidic Paper Analytical Devices.

Science.gov (United States)

Shangguan, Jin-Wen; Liu, Yu; Wang, Sha; Hou, Yun-Xuan; Xu, Bi-Yi; Xu, Jing-Juan; Chen, Hong-Yuan

2018-06-06

Paper capillary is introduced to enable effective sampling on microfluidic paper analytical devices. By coupling mac-roscale capillary force of paper capillary and microscale capillary forces of native paper, fluid transport can be flexibly tailored with proper design. Subsequently, a hybrid-fluid-mode paper capillary device was proposed, which enables fast and reliable sampling in an arrayed form, with less surface adsorption and bias for different components. The resulting device thus well supports high throughput, quantitative, and repeatable assays all by hands operation. With all these merits, multiplex analysis of ions, proteins, and microbe have all been realized on this platform, which has paved the way to level-up analysis on μPADs.

3rd ICTs and Society Meeting; Paper Session - Theorizing the Internet; Paper 4: A Methodological Reflection on Converging Technologies and Their Relevance to Informa-tion Ethics

Directory of Open Access Journals (Sweden)

Pak-Hang Wong

2010-06-01

Full Text Available In light of converging technologies, there is a clear sense that ethicists of various technological domains are coming together. Or, that they should come together. Yet, despite increasing cooperation and boundary-crossing in various fields of the ethics of technology, these efforts remain mostly at topical level. Relatively little attention has been given to issues on methodologies. The current paper aims to contribute to the current research by raising the methodological issues. In this paper, my objective is to argue that ethics of Information Technology (or Information Ethics (IE can benefit from the insights in other fields of the ethics of technology. Drawing the insights from other fields of the ethics of technology, I shall propose a systematic account of an Empirical Information Ethics (EIE

CONTRIBUTION OF INDIRECT TAXES

Directory of Open Access Journals (Sweden)

CHIRCULESCU MARIA FELICIA

2015-08-01

Full Text Available The work is based on the fact that at any time and in any society, taxation is regarded as undesirable for all taxpayers. The existence and it's manifestation is justified, because the operation of any company involves costs that must be covered by sufficient resources. Since ancient times, each state has adopted its own tax system, more or less perfected, as the state has experienced a greater or lesser economic and military power At the base of this work stays the fact that tax systems are a key factor influencing the overall efficiency of the economy. They determine the size tendency to save, invest and work, influencing the increase in production and employment, which is essential sights integral economic strategy, making tax reform an important component of economic reform. This paper aims to analyze the indirect taxes and their contribution to the public revenues in Romania, the purpose paper contains an analysis based on statistical series as indirect taxation is where tax harmonization was possible. Through analyzes, the paper aims to provide answers to the problem of the contradiction between the growing need for budgetary revenues, which entails a continuous amplification and diversification of taxation, on the one hand, and the need to stimulate economic development, on the other hand. The harmonization of indirect taxation had been achieved since this touches the free movement of goods and the freedom to supply services, not being able to say the same thing about direct taxation, which is why the European Community Treaty does not specify expressly the alignment of direct taxation, considering that direct taxation is a matter of Internal Policies that, for a country free option.

White paper on atomic energy in 2004

International Nuclear Information System (INIS)

2005-03-01

Since the publication of its last White Paper on Nuclear Energy in 2003, the Atomic Energy Commission of Japan (AEC) summarized trends covering all aspects of nuclear energy over the period up to December 2004. This paper is comprised of a main document and supplementary materials. The first chapter of the main document summarizes the current activities toward national and international understanding and trust promotion of nuclear energy divided along the topics of 'Restoring trust', 'Structuring trust toward new enterprise implementation', 'Establishment of understanding and trust of international society', 'AEC's activities toward creation of new Long-Term Program', and 'Establishment of future understanding and trust. 'The second chapter summarized recent trends of national and private activities based on the Long-Term Program created in November 2000, covering the topics 'Nuclear Energy Policy in Japan', 'Harmony between People, Society and Nuclear Energy', 'Nuclear Power Generation and the Nuclear Fuel Cycle', 'Diversified Development of Nuclear Science and Technology', 'Utilization of Radiation Contributing to People's Lives', 'Harmony between International Society and Nuclear Energy', and 'Foundation to Promote Research, Development and Utilization of Nuclear Energy'. The supplementary materials include lists of AEC decisions, nuclear energy budgets, year-by-year data tables, and other such similar materials. (T. Tanaka)

The Contribution of Intellectual Capital to Value Creation

Directory of Open Access Journals (Sweden)

Elena Shakina

2013-12-01

Full Text Available This paper studies the marginal contribution of intellectual capital (IC components to company value using a hedonic pricing framework. The ANOVA is used to identify group differences among different national markets and industries. Two models have been developed to reflect the time effect: one related to the immediate creation of value and another for the long term. As could be expected, the contribution of IC to companies’ value creation differs significantly between countries and industries. Both models, short- and long-term, are significant and with a normal explanatory power. We have found both positive and negative coefficients. Human capital plays a critical positive role in value creation in the short term. Structural and relational capital becomes more relevant in the long term. However, in the long term, the results obtained regarding the effect of human capital are unclear.

Monitoring fetal heart rate during pregnancy: contributions from advanced signal processing and wearable technology.

Science.gov (United States)

Signorini, Maria G; Fanelli, Andrea; Magenes, Giovanni

2014-01-01

Monitoring procedures are the basis to evaluate the clinical state of patients and to assess changes in their conditions, thus providing necessary interventions in time. Both these two objectives can be achieved by integrating technological development with methodological tools, thus allowing accurate classification and extraction of useful diagnostic information. The paper is focused on monitoring procedures applied to fetal heart rate variability (FHRV) signals, collected during pregnancy, in order to assess fetal well-being. The use of linear time and frequency techniques as well as the computation of non linear indices can contribute to enhancing the diagnostic power and reliability of fetal monitoring. The paper shows how advanced signal processing approaches can contribute to developing new diagnostic and classification indices. Their usefulness is evaluated by comparing two selected populations: normal fetuses and intra uterine growth restricted (IUGR) fetuses. Results show that the computation of different indices on FHRV signals, either linear and nonlinear, gives helpful indications to describe pathophysiological mechanisms involved in the cardiovascular and neural system controlling the fetal heart. As a further contribution, the paper briefly describes how the introduction of wearable systems for fetal ECG recording could provide new technological solutions improving the quality and usability of prenatal monitoring.

Climate change - the contribution from air travel

International Nuclear Information System (INIS)

Beesley, Colin

2000-01-01

The paper discusses the Intergovernment Panel on Climate Change (IPCC) report on Aviation and the Global Atmosphere (published in 1999). It was considered necessary to treat air transport on its own since aircraft are unique in delivering emissions into the upper atmosphere rather than at ground level. The study was commissioned at the request of the International Civil Aviation Organisation and the Montreal Protocol. More than 300 experts contributed and the report has quantified the effect of aviation on the atmosphere on a world wide basis and highlighted areas where improved data are required. (UK)

From paper to digital documents : Challenging and improving the SGML approach

OpenAIRE

Sandahl, Tone Irene

1999-01-01

This research has been initiated on the basis of practical experiences in developing a relatively large SGML system at the University of Oslo. This thesis contributes to the field of information systems, with a particular focus on document systems. The aim of this work is to inform the design of document systems by considering the transformation from paper to digital documents in organizations. The Standard Generalized Markup Language (SGML, ISO 8879) approach is emphasized. The SGML approach...

PaperBLAST: Text Mining Papers for Information about Homologs

International Nuclear Information System (INIS)

Price, Morgan N.; Arkin, Adam P.

2017-01-01

Large-scale genome sequencing has identified millions of protein-coding genes whose function is unknown. Many of these proteins are similar to characterized proteins from other organisms, but much of this information is missing from annotation databases and is hidden in the scientific literature. To make this information accessible, PaperBLAST uses EuropePMC to search the full text of scientific articles for references to genes. PaperBLAST also takes advantage of curated resources (Swiss-Prot, GeneRIF, and EcoCyc) that link protein sequences to scientific articles. PaperBLAST’s database includes over 700,000 scientific articles that mention over 400,000 different proteins. Given a protein of interest, PaperBLAST quickly finds similar proteins that are discussed in the literature and presents snippets of text from relevant articles or from the curators. With the recent explosion of genome sequencing data, there are now millions of uncharacterized proteins. If a scientist becomes interested in one of these proteins, it can be very difficult to find information as to its likely function. Often a protein whose sequence is similar, and which is likely to have a similar function, has been studied already, but this information is not available in any database. To help find articles about similar proteins, PaperBLAST searches the full text of scientific articles for protein identifiers or gene identifiers, and it links these articles to protein sequences. Then, given a protein of interest, it can quickly find similar proteins in its database by using standard software (BLAST), and it can show snippets of text from relevant papers. We hope that PaperBLAST will make it easier for biologists to predict proteins’ functions.

Combinatorics Advances : Papers from a Conference

CERN Document Server

Mahmoodian, Ebadollah

1995-01-01

On March 28~31, 1994 (Farvardin 8~11, 1373 by Iranian calendar), the Twenty­ fifth Annual Iranian Mathematics Conference (AIMC25) was held at Sharif University of Technology in Tehran, Islamic Republic of Iran. Its sponsors in~ eluded the Iranian Mathematical Society, and the Department of Mathematical Sciences at Sharif University of Technology. Among the keynote speakers were Professor Dr. Andreas Dress and Professor Richard K. Guy. Their plenary lec~ tures on combinatorial themes were complemented by invited and contributed lectures in a Combinatorics Session. This book is a collection of refereed papers, submitted primarily by the participants after the conference. The topics covered are diverse, spanning a wide range of combinatorics and al~ lied areas in discrete mathematics. Perhaps the strength and variety of the pa~ pers here serve as the best indications that combinatorics is advancing quickly, and that the Iranian mathematics community contains very active contributors. We hope that you find the p...

Promoting Social Entrepreneurship among Entrepreneur with Disabilities in Contribution for Community

Directory of Open Access Journals (Sweden)

Rozali Norhasyikin

2018-01-01

Full Text Available Looking forward of the uniqueness social entrepreneurship (SE new phenomena born from entrepreneurships felid. Because of that it is a new step point for the entrepreneur with disabilities (EWD to be part of social entrepreneurship environments. Where SE, link the positive impact for society creating by entrepreneur that understand that social problem give a big opportunities for profit or nonprofit activity that can be solve creatively. This give a lot of advantage of EWD to contributes to community in the term of “social impact”. This conceptual paper maps SE and EWD in contribution to community with the important role play by stakeholder in promoting SE. This conceptualization enhances understanding of EWD in SE and clear picture of role play by stakeholder give chances for EWD contributes to community.

NLL order contributions for exclusive processes in jet-calculus scheme

International Nuclear Information System (INIS)

Tanaka, Hidekazu

2011-01-01

We investigate the next-to-leading logarithmic (NLL) order contributions of the quantum chromodynamics (QCD) for exclusive processes evaluated by Monte Carlo methods. Ambiguities of the Monte Carlo calculation based on the leading-logarithmic (LL) order approximations are pointed out. To remove these ambiguities, we take into account the NLL order terms. In a model presented in this paper, interference contributions due to the NLL order terms are included for the generation of the transverse momenta in initial-state parton radiations. Furthermore, a kinematical constraint due to parton radiation, which is also a part of the NLL order contributions, is taken into account. This method guarantees a proper phase space boundary for hard scattering cross sections as well as parton radiations. As an example, cross sections for lepton pair productions mediated by a virtual photon in hadron-hadron collisions are calculated, using the jet-calculus scheme for flavor nonsinglet quarks. (author)

Lunar and terrestrial planet formation in the Grand Tack scenario

Science.gov (United States)

Jacobson, S. A.; Morbidelli, A.

2014-01-01

We present conclusions from a large number of N-body simulations of the giant impact phase of terrestrial planet formation. We focus on new results obtained from the recently proposed Grand Tack model, which couples the gas-driven migration of giant planets to the accretion of the terrestrial planets. The giant impact phase follows the oligarchic growth phase, which builds a bi-modal mass distribution within the disc of embryos and planetesimals. By varying the ratio of the total mass in the embryo population to the total mass in the planetesimal population and the mass of the individual embryos, we explore how different disc conditions control the final planets. The total mass ratio of embryos to planetesimals controls the timing of the last giant (Moon-forming) impact and its violence. The initial embryo mass sets the size of the lunar impactor and the growth rate of Mars. After comparing our simulated outcomes with the actual orbits of the terrestrial planets (angular momentum deficit, mass concentration) and taking into account independent geochemical constraints on the mass accreted by the Earth after the Moon-forming event and on the time scale for the growth of Mars, we conclude that the protoplanetary disc at the beginning of the giant impact phase must have had most of its mass in Mars-sized embryos and only a small fraction of the total disc mass in the planetesimal population. From this, we infer that the Moon-forming event occurred between approximately 60 and approximately 130 Myr after the formation of the first solids and was caused most likely by an object with a mass similar to that of Mars. PMID:25114304

Contributions of Qualitative Research to Understanding Savings for Children and Youth

Science.gov (United States)

Sherraden, Margaret; Peters, Clark; Wagner, Kristen; Guo, Baorong; Clancy, Margaret

2013-01-01

This paper explores contributions of qualitative research to saving theory for children, youth, and parents in children's development account (CDAs) programs. It brings together findings from three studies: (1) elementary school age children saving for college, (2) youth transitioning from foster care saving for education and other purposes, and…

Laminated and infused Parafilm® - paper for paper-based analytical devices.

Science.gov (United States)

Kim, Yong Shin; Yang, Yuanyuan; Henry, Charles S

2018-02-01

Numerous fabrication methods have been reported for microfluidic paper-based analytical devices (μPADs) using barrier materials ranging from photoresist to wax. While these methods have been used with wide success, consistently producing small, high-resolution features using materials and methods that are compatible with solvents and surfactants remains a challenge. Two new methods are presented here for generating μPADs with well-defined, high-resolution structures compatible with solvents and surfactant-containing solutions by partially or fully fusing paper with Parafilm® followed by cutting with a CO 2 laser cutter. Partial fusion leads to laminated paper ( l -paper) while the complete fusion results in infused paper ( i -paper). Patterned structures in l -paper were fabricated by selective removal of the paper but not the underlying Parafilm® using a benchtop CO 2 laser. Under optimized conditions, a gap as small as 137 ± 22 μm could be generated. Using this approach, a miniaturized paper 384-zone plate, consisting of circular detection elements with a diameter of 1.86 mm, was fabricated in 64 × 43 mm 2 area. Furthermore, these ablation-patterned substrates were confirmed to be compatible with surfactant solutions and common organic solvents (methanol, acetonitrile and dimethylformamide), which has been achieved by very few μPAD patterning techniques. Patterns in i -paper were created by completely cutting out zones of the i -paper and then fixing pre-cut paper into these openings similar to the strategy of fitting a jigsaw piece into a puzzle. Upon heating, unmodified paper was readily sealed into these openings due to partial reflow of the paraffin into the paper. This unique and simple bonding method was illustrated by two types of 3D μPADs, a push-on valve and a time-gated flow distributor, without adding adhesive layers. The free-standing jigsaw-patterned sheets showed good structural stability and solution compatibility, which provided a facile

Migration and growth of protoplanetary embryos. I. Convergence of embryos in protoplanetary disks

Energy Technology Data Exchange (ETDEWEB)

Zhang, Xiaojia; Lin, Douglas N. C. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Liu, Beibei [Kavli Institute for Astronomy and Astrophysics and Department of Astronomy, School of Physics, Peking University, Beijing 100871 (China); Li, Hui, E-mail: xzhang47@ucsc.edu [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

2014-12-10

According to the core accretion scenario, planets form in protostellar disks through the condensation of dust, coagulation of planetesimals, and emergence of protoplanetary embryos. At a few AU in a minimum mass nebula, embryos' growth is quenched by dynamical isolation due to the depletion of planetesimals in their feeding zone. However, embryos with masses (M{sub p} ) in the range of a few Earth masses (M {sub ⊕}) migrate toward a transition radius between the inner viscously heated and outer irradiated regions of their natal disk. Their limiting isolation mass increases with the planetesimals surface density. When M{sub p} > 10 M {sub ⊕}, embryos efficiently accrete gas and evolve into cores of gas giants. We use a numerical simulation to show that despite stream line interference, convergent embryos essentially retain the strength of non-interacting embryos' Lindblad and corotation torques by their natal disks. In disks with modest surface density (or equivalently accretion rates), embryos capture each other in their mutual mean motion resonances and form a convoy of super-Earths. In more massive disks, they could overcome these resonant barriers to undergo repeated close encounters, including cohesive collisions that enable the formation of massive cores.

FORMING CIRCUMBINARY PLANETS: N-BODY SIMULATIONS OF KEPLER-34

International Nuclear Information System (INIS)

Lines, S.; Leinhardt, Z. M.; Paardekooper, S.; Baruteau, C.; Thebault, P.

2014-01-01

Observations of circumbinary planets orbiting very close to the central stars have shown that planet formation may occur in a very hostile environment, where the gravitational pull from the binary should be very strong on the primordial protoplanetary disk. Elevated impact velocities and orbit crossings from eccentricity oscillations are the primary contributors to high energy, potentially destructive collisions that inhibit the growth of aspiring planets. In this work, we conduct high-resolution, inter-particle gravity enabled N-body simulations to investigate the feasibility of planetesimal growth in the Kepler-34 system. We improve upon previous work by including planetesimal disk self-gravity and an extensive collision model to accurately handle inter-planetesimal interactions. We find that super-catastrophic erosion events are the dominant mechanism up to and including the orbital radius of Kepler-34(AB)b, making in situ growth unlikely. It is more plausible that Kepler-34(AB)b migrated from a region beyond 1.5 AU. Based on the conclusions that we have made for Kepler-34, it seems likely that all of the currently known circumbinary planets have also migrated significantly from their formation location with the possible exception of Kepler-47(AB)c

FORMING CIRCUMBINARY PLANETS: N-BODY SIMULATIONS OF KEPLER-34

Energy Technology Data Exchange (ETDEWEB)

Lines, S.; Leinhardt, Z. M. [School of Physics, University of Bristol, H. H. Wills Physics Laboratory, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Paardekooper, S.; Baruteau, C. [DAMTP, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA (United Kingdom); Thebault, P., E-mail: stefan.lines@bristol.ac.uk [LESIA-Observatoire de Paris, UPMC Univ. Paris 06, Univ. Paris-Diderot, F-92195 Meudon Cedex (France)

2014-02-10

Observations of circumbinary planets orbiting very close to the central stars have shown that planet formation may occur in a very hostile environment, where the gravitational pull from the binary should be very strong on the primordial protoplanetary disk. Elevated impact velocities and orbit crossings from eccentricity oscillations are the primary contributors to high energy, potentially destructive collisions that inhibit the growth of aspiring planets. In this work, we conduct high-resolution, inter-particle gravity enabled N-body simulations to investigate the feasibility of planetesimal growth in the Kepler-34 system. We improve upon previous work by including planetesimal disk self-gravity and an extensive collision model to accurately handle inter-planetesimal interactions. We find that super-catastrophic erosion events are the dominant mechanism up to and including the orbital radius of Kepler-34(AB)b, making in situ growth unlikely. It is more plausible that Kepler-34(AB)b migrated from a region beyond 1.5 AU. Based on the conclusions that we have made for Kepler-34, it seems likely that all of the currently known circumbinary planets have also migrated significantly from their formation location with the possible exception of Kepler-47(AB)c.

Forming Circumbinary Planets: N-body Simulations of Kepler-34

Science.gov (United States)

Lines, S.; Leinhardt, Z. M.; Paardekooper, S.; Baruteau, C.; Thebault, P.

2014-02-01

Observations of circumbinary planets orbiting very close to the central stars have shown that planet formation may occur in a very hostile environment, where the gravitational pull from the binary should be very strong on the primordial protoplanetary disk. Elevated impact velocities and orbit crossings from eccentricity oscillations are the primary contributors to high energy, potentially destructive collisions that inhibit the growth of aspiring planets. In this work, we conduct high-resolution, inter-particle gravity enabled N-body simulations to investigate the feasibility of planetesimal growth in the Kepler-34 system. We improve upon previous work by including planetesimal disk self-gravity and an extensive collision model to accurately handle inter-planetesimal interactions. We find that super-catastrophic erosion events are the dominant mechanism up to and including the orbital radius of Kepler-34(AB)b, making in situ growth unlikely. It is more plausible that Kepler-34(AB)b migrated from a region beyond 1.5 AU. Based on the conclusions that we have made for Kepler-34, it seems likely that all of the currently known circumbinary planets have also migrated significantly from their formation location with the possible exception of Kepler-47(AB)c.

Project management and performance management: potential transdisciplinary contributions

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Gerrit van der Waldt

2012-12-01

Full Text Available As project management and performance management as management applications gain momentum in public sector settings, the question often arise as to if, how, and when these applications should complement each other in various policy implementation and service delivery initiatives. Answers to this question should be sought from various vantage points or perspectives. These vantage points may range from macro, meso, micro as well as theoretical-methodological perspectives. The purpose of this paper is to unlock the potential for transdisciplinary contributions between Project Management and Performance Management by focusing on the methodologies, functional areas, and practical applications of both management disciplines. It is argued that the respective methodologies and their processes should be unpacked to identify the timing or moment when each discipline could, and should, make a contribution to the success of the other. This will add value to the theoretical underpinnings and practical applications of both study domains in the public sector. The respective contributions are illustrated by means of application realities of both management practices in the South African Public Service. Keywords: project management, performance management, Public Sector applications, transdisciplinarity Disciplines: project management, performance management

Paper Cuts.

Science.gov (United States)

Greene, Lisa A.

1990-01-01

Describes how to create paper cuts and suggests the most appropriate materials for young children that give good quality results. Describes the methods the author, a professional artist, uses to assemble her own paper cuts and how these can be adopted by older students. (KM)

The Nature of Human Disposition: al-Ghazālī's Contribution to an Islamic Concept of Personality

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Abbas Husein Ali

1995-06-01

Full Text Available The paper provides a critique of contemporary psychological models of human nature and highlights the contribution of al-Ghazālī towards a better conceptualization of human disposition. A brief outline of the philosophical foundations of the three major psychological approaches–Freudian psychoanalysis, Skinnerian behaviorism, and Rogerian and Maslowvian Humanism– are provided. Consequently, the metaphors they adopted for human nature are discussed. The paper also highlights the shortcomings of these models by looking at their practical implications, particularly for psychology of personality. The last part of the paper dwells on al-Ghazālī’s contribution to an Islamic abstraction of human disposition and personality.

Decomposing the Education Wage Gap: Everything but the Kitchen Sink. Working Paper 2010-12

Science.gov (United States)

Hotchkiss, Julie L.; Shiferaw, Menbere

2010-01-01

This paper contributes to a large literature concerned with identifying the source of the widening wage gap between high school and college graduates by providing a comprehensive, multidimensional decomposition of wages across both time and educational status. Data from a multitude of sources are brought to bear on the question of the relative…

Extending the limits of paper recycling - improvements along the paper value chain

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A. Blanco

2013-12-01

Full Text Available Aim of study: The purpose of this study is to analyze how paper recycling activities in Europe can be extended through different improvements along the paper value chain. The importance of this study lies in the identification of the present barriers in paper recycling and how they can be overcome.Area of study: Europe.Material and Methods: All the main stages along the paper value chain have been analyzed for possible improvements: collection of recovered paper (availability and quality, sorting of recovered paper, paper production, and printing and converting activities.Main results: To increase paper recycling in Europe the following improvements are necessary. First, it is mandatory to increase the availability of recovered paper through more efficient collection systems (avoiding the use of commingled collection systems and limiting the competition with energy purposes and the exports. Second, it is necessary to extend sorting activities, which can be achieved by reducing sorting costs by the use of automatized sorting systems. Third, there is a need to increase the recyclability of paper products by the commitment of printing and converting industries to use recycling-friendly printing inks and adhesives. Finally, environmental awareness of the citizens is still an important driver for increasing recycling activities, affecting not only recovery but to all the stages along the paper recycling chain.Research highlights: Although the recycling rate in Europe is already very high (68.9%, there is still room to further extend paper recycling activities through different improvements along the paper value chain.Keywords: paper recycling; sustainability; paper value chain; recovered paper; environmental awareness.

Improve Research Visibility and Impact by Contributing to Wikipedia

OpenAIRE

Ebrahim, Nader Ale

2017-01-01

Wikipedia is a tool for collaboration, information sharing and knowledge/content management which anyone can edit. Wikipedia is widely used by students during the research process. So, due to Wikipedia popularity, contributing to Wikipedia website is one way of increasing citation score. In this workshop, I try to answer “Does including your papers as citations on Wikipedia increase the number of academic citations you get?” if yes, how?.

Upward Feedback and Its Contribution to Employees' Feeling of Self-Determination

Science.gov (United States)

Bauer, Johannes; Mulder, Regina H.

2006-01-01

Purpose--The paper seeks to show that self-determination is a widely regarded motivational variable in educational research that relates to intrinsically motivated, self-directed learning at work. This study aimed to find out whether the possibility to provide upward feedback to supervisors contributes to employees' feelings of self-determination.…

How to Write (Even) Better Academic Student Reports and Papers

DEFF Research Database (Denmark)

Prætorius, Thim

2017-01-01

and Content of an Academic Report/Paper covers the seven required parts that make up an academic piece of work. That is, introduction (e.g., setting the hook), theory and/or literature review (e.g., which literature to you draw on and contribute to), methods (how did you study the research question), findings......Writing good academic papers or reports that demonstrate academic rigour is not necessarily easy for university students (or academics for that matter). Common problems include lacking academic rigour when studying the research problem and difficulties in identifying literature and using theo-ry...... students write methods before theory but doing so means you need to operationalize theory before you have introduced it. The second theme, Gen-eral Tips and Tricks, provide rules of thumb (e.g., that you should kill your darlings), writing style and argumentation hints (e.g., use direct voice) and layout...

Thermodynamic contributions of deforestation to global climate change

International Nuclear Information System (INIS)

Bell, A.

2009-01-01

This paper examines a portion of the thermodynamics of global warming. The calculations use the endothermic photosynthesis reaction and yearly measures of CO 2 uptake to determine the amount of energy that is absorbed by forest cover each year. The energy absorption value of forest coverage determines the yearly cost of deforestation. The calculations reveal that 3.92 * 10 15 kJ less solar energy is absorbed by global forest coverage because of deforestation each year. The energy is enough to warm the atmosphere by 0.00008 °C / year. By comparison the same amount of energy represents 0.001 % of the atmospheric energy gains between 1995 and 2003. The results of this paper raise questions about the nature of global warming and the possibility that thermodynamic contributions to global climate change are significant. (author)

Paper-pen peer-correction versus wiki-based peer-correction

Directory of Open Access Journals (Sweden)

Froldova Vladimira

2016-01-01

Full Text Available This study reports on the comparison of the students’ achievement and their attitudes towards the use of paper-pen peer-correction and wiki-based peer-correction within English language lessons and CLIL Social Science lessons at the higher secondary school in Prague. Questionnaires and semi-structured interviews were utilized to gather information. The data suggests that students made considerable use of wikis and showed higher degrees of motivation in wiki-based peer-correction during English language lessons than in CLIL Social Science lessons. In both cases wikis not only contributed to developing students’ writing skills, but also helped students recognize the importance of collaboration.

Contributions of fast breeder test reactor to the advanced technology in India

International Nuclear Information System (INIS)

Kapoor, R.P.

2001-01-01

Fast Breeder Test Reactor (FBTR) is a 40 MWt/13.2 MWe loop type, sodium cooled, plutonium rich mixed carbide fuelled reactor. Its operation at Indira Gandhi Centre for Atomic Research, since first criticality in 1985, has contributed immensely to the advancement of this multidisciplinary and complex fast breeder technology in the country. It has also given a valuable operational feedback for the design of 500 MWe Prototype Fast Breeder Reactor. This paper highlights FBTR's significant contributions to this important technology which has a potential to provide energy security to the country in future. (author)

Paper reutilization to manufacture plasterboard; Reaproveitamento de papel para confeccao de placas de gesso

Energy Technology Data Exchange (ETDEWEB)

Calixto, M.K.; Medeiros, I.A.; Lima, R.C.; Araujo, Y.C.F.; Lima, E.M.C. de, E-mail: mayraksc@gmail.com [Centro Universitario UNIFACISA, Campina Grande, PB (Brazil)

2016-07-01

The changes in the planet have accelerated the discussion about environmental preservation and the pursuit for sustainable solutions aiming the human development. In the civil construction, the residue recovery, not only contribute to sustainability but also relieves the consumption of raw material and for all this the search for new products in this new twist is in the center of global technological research. The goal of this work is to obtain plasterboard incorporating discarded paper in the educational environment. In this study, the plaster was characterized initially by X-ray diffraction and thermals analysis (TG e DTA). It was prepared a paste of plaster and processed paper varying the paper amount in two proportions with 10% and 50% respectively, and was utilized the plaster/water factor equals to 0,7. The plaster - paper mixtures were characterized about the setting time and compressive strength. The results indicated that the increase in paper content led to the decreased resistance. (author)

United theory of planet formation (i): Tandem regime

Science.gov (United States)

Ebisuzaki, Toshikazu; Imaeda, Yusuke

2017-07-01

The present paper is the first one of a series of papers that present the new united theory of planet formation, which includes magneto-rotational instability and porous aggregation of solid particles in an consistent way. We here describe the ;tandem; planet formation regime, in which a solar system like planetary systems are likely to be produced. We have obtained a steady-state, 1-D model of the accretion disk of a protostar taking into account the magneto-rotational instability (MRI) and and porous aggregation of solid particles. We find that the disk is divided into an outer turbulent region (OTR), a MRI suppressed region (MSR), and an inner turbulent region (ITR). The outer turbulent region is fully turbulent because of MRI. However, in the range, rout(= 8 - 60 AU) from the central star, MRI is suppressed around the midplane of the gas disk and a quiet area without turbulence appears, because the degree of ionization of gas becomes low enough. The disk becomes fully turbulent again in the range rin(= 0.2 - 1 AU), which is called the inner turbulent region, because the midplane temperature become high enough (>1000 K) due to gravitational energy release. Planetesimals are formed through gravitational instability at the outer and inner MRI fronts (the boundaries between the MRI suppressed region (MSR) and the outer and inner turbuent regions) without particle enhancement in the original nebula composition, because of the radial concentration of the solid particles. At the outer MRI front, icy particles grow through low-velocity collisions into porous aggregates with low densities (down to ∼10-5 gcm-3). They eventually undergo gravitational instability to form icy planetesimals. On the other hand, rocky particles accumulate at the inner MRI front, since their drift velocities turn outward due to the local maximum in gas pressure. They undergo gravitational instability in a sub-disk of pebbles to form rocky planetesimals at the inner MRI front. They are likely

China's growing contribution to global intracranial aneurysm research (1991-2012: a bibliometric study.

Directory of Open Access Journals (Sweden)

Ze-jun Jia

Full Text Available BACKGROUND: We sought to analyze the growing worldwide trends of intracranial aneurysm research, investigate China's recent contribution, and compare the contributions of mainland China, Taiwan, and Hong Kong. METHODS: Global and China intracranial aneurysm-related publications were retrieved from the Web of Science database from 1991 to 2012. Excel 2007, Matlab, and Thomson Data Analyzer (TDA software were used to analyze the search results for number of publications, cited frequency, h-index, and organization contributions. RESULTS: 16468 global papers were identified that were cited 273500 times until 2013-08-15. The United States accounted for 31.497% of the articles, 58.64% of the citations, and the highest h-index (127. Japan and Germany followed in frequency. China's articles ranked eighth (third in 2012 in total number, with most of the contributions occurring since 2002 (91.33%. China was at the early stage of the logic growth curve (exponential growth, with the citation frequency and h-index per year increasing. The quality of the publications was low. The main research centers were located in Beijing, Shanghai, Taiwan, and Hong Kong. The main Asian funding body was the National Natural Science Foundation of China. The number of publications and frequency of citations of papers from mainland China was greater than that of Taiwan or Hong Kong. CONCLUSION: Global intracranial aneurysm research has been developing swiftly since 1991, with the United States making the largest contribution. Research in China started later, in 2002. Since then, China has increased its rate of publication, and became the third largest contributor by 2012.

CALL FOR PAPERS: Special issue on Current Trends in Integrability and Nonlinear Phenomena Special issue on Current Trends in Integrability and Nonlinear Phenomena

Science.gov (United States)

Gómez-Ullate, D.; Lombardo, S.; Mañas, M.; Mazzocco, M.; Nijhoff, F.; Sommacal, M.

2009-12-01

This is a call for contributions to a special issue of Journal of Physics A: Mathematical and Theoretical dedicated to integrability and nonlinear phenomena. The motivation behind this special issue is to summarize in a single comprehensive publication, the main aspects (past and present), latest developments, different viewpoints and the directions being followed in this multidisciplinary field. We hope that such a special issue could become a particularly valuable reference for the broad scientific community working in integrability and nonlinear phenomena. Editorial policy The Editorial Board has invited D Gómez-Ullate, S Lombardo, M Mañas, M Mazzocco, F Nijhoff and M Sommacal to serve as Guest Editors for the special issue. Their criteria for the acceptance of contributions are as follows. The subject of the paper should relate to the following list of subjects: Integrable systems (including quantum and discrete) and applications Dynamical systems: Hamiltonian systems and dynamics in the complex domain Nonlinear waves, soliton equations and applications Nonlinear ODEs including Painlevé equations and isomonodromic deformations Symmetries and perturbative methods in the classification of integrable PDEs Infinite dimensional Lie algebras and integrable systems Orthogonal polynomials, random matrix theory All contributions will be refereed and processed according to the usual procedure of the journal. Papers should report original and significant research that has not already been published. Guidelines for preparation of contributions The DEADLINE for contributed papers will be 28 February 2010. This deadline will allow the special issue to appear in October 2010. There is a nominal page limit of 15 printed pages per contribution (invited review papers can be longer). For papers exceeding this limit, the Guest Editors reserve the right to request a reduction in length. Further advice on publishing your work in Journal of Physics A: Mathematical and Theoretical

Increasing number of authors per paper in Korean science and technology papers

Directory of Open Access Journals (Sweden)

Hyunju Jang

2016-08-01

Full Text Available We examined changes in the number of authors per paper for science and technology papers (agricultural sciences, engineering and technologies, medical sciences, and natural sciences in Korea. We employed the Scopus database to examine the change in the number of authors in papers, which were published from 2000 to 2015 in the 234 Korean academic journals indexed on Scopus. We found that the global trend of growth in the number of authors per paper is evident in Korea as well. While there was little evidence of a correlation with the citation per paper, a positive correlation was found between with the field-weighted citation impact, another measure of a paper’s impact, in medical and natural science papers. In terms of the type of collaboration, we found that international collaboration papers had the highest number of authors, followed by national and institutional collaborations. The number of authors per paper was highest for those published in the top 10% journals by Source Normalized Impact per Paper, followed by Scopus-indexed journals, while papers published in Korea Citation Index had the lowest number of authors per paper. We propose that the rise in the number of authors per paper in Korean papers may be ascribed to many Korean research programs encouraging group research and the widespread availability of the internet, which has stimulated joint research efforts and encouraged international collaboration.

Cited Brazilian papers in general surgery between 1970 and 2009

Directory of Open Access Journals (Sweden)

Flavio L. Heldwein

2010-01-01

Full Text Available OBJECTIVES: To identify the most cited articles in general surgery published by Brazilian authors. INTRODUCTION: There are several ways for the international community to recognize the quality of a scientific article. Although controversial, the most widely used and reliable methodology to identify the importance of an article is citation analysis. METHODS: A search using the Institute for Scientific Information citation database (Science Citation Index Expanded was performed to identify highly cited Brazilian papers published in twenty-six highly cited general surgery journals, selected based on their elevated impact factors, from 1970 to 2009. Further analysis was done on the 65 most-cited papers. RESULTS: We identified 1,713 Brazilian articles, from which nine papers emerged as classics (more than 100 citations received. For the Brazilian contributions, a total increase of about 21-fold was evident between 1970 and 2009. Although several topics were covered, articles covering trauma, oncology and organ transplantation were the most cited. The majority of classic studies were done with international cooperation. CONCLUSIONS: This study identified the most influential Brazilian articles published in internationally renowned general surgery journals.

CONTRIBUTIONS FOR DEVELOPING OF A COMPUTER AIDED LEARNING ENVIRONMENT OF DESCRIPTIVE GEOMETRY

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Antonescu Ion

2009-07-01

Full Text Available The paper presents the authors’ contributions for developing a computer code for teaching of descriptive geometry using the computer aided learning techniques. The program was implemented using the programming interface and the 3D modeling capabilities of the AutoCAD system.

Taxing Meat: Taking Responsibility for One's Contribution to Antibiotic Resistance.

Science.gov (United States)

Giubilini, Alberto; Birkl, Patrick; Douglas, Thomas; Savulescu, Julian; Maslen, Hannah

2017-04-01

Antibiotic use in animal farming is one of the main drivers of antibiotic resistance both in animals and in humans. In this paper we propose that one feasible and fair way to address this problem is to tax animal products obtained with the use of antibiotics. We argue that such tax is supported both by (a) deontological arguments, which are based on the duty individuals have to compensate society for the antibiotic resistance to which they are contributing through consumption of animal products obtained with the use of antibiotics; and (b) a cost-benefit analysis of taxing such animal products and of using revenue from the tax to fund alternatives to use of antibiotics in animal farming. Finally, we argue that such a tax would be fair because individuals who consume animal products obtained with the use of antibiotics can be held morally responsible, i.e. blameworthy, for their contribution to antibiotic resistance, in spite of the fact that each individual contribution is imperceptible.

Far-zone contributions of airborne gravity anomalies' upward/downward continuation

Directory of Open Access Journals (Sweden)

Boyang Zhou

2016-11-01

Full Text Available Airborne gravimetry has become a vital technique in local gravity field approximation, and upward/downward continuation of gravity data is a key process of airborne gravimetry. In these procedures, the integral domain is divided into two parts, namely the near-zone and the far-zone. The far-zone contributions are approximated by the truncation coefficients and a global geo-potential model, and their values are controlled by several issues. This paper investigates the effects of flight height, the size of near-zone cap, and Remove-Compute-Restore (RCR technique upon far-zone contributions. Results show that at mountainous area the far-zone contributions can be ignored when EIGEN-6C of 360 degree is removed from the gravity data, together with a near-zone cap of 1° and a flight height less than 10 km, while at flat area EIGEN-6C of 180 degree is feasible.

The nursing contribution to nutritional care in cancer cachexia.

Science.gov (United States)

Hopkinson, Jane B

2015-11-01

Cancer cachexia is a complex syndrome. Its defining feature is involuntary weight loss, which arises, in part, because of muscle atrophy and is accompanied by functional decline. International expert consensus recommends that nutritional support and counselling is a component of multimodal therapy for cancer cachexia, as poor nutritional intake can contribute to progression of the syndrome. The present paper focuses on what is presently known about the nursing contribution to nutritional care in cancer cachexia. There is potential for nurses to play an important role. However, obstacles to this include lack of a robust evidence base to support their nutritional care practices and unmet need for education about nutrition in cancer. The nursing role's boundaries and the outcomes of nurse-delivered nutritional care in cancer cachexia are both uncertain and should be investigated.

Iranians' contribution to world literature on neuroscience.

Science.gov (United States)

Ashrafi, Farzad; Mohammadhassanzadeh, Hafez; Shokraneh, Farhad; Valinejadi, Ali; Johari, Karim; Saemi, Nazanin; Zali, Alireza; Mohaghegh, Niloofar; Ashayeri, Hassan

2012-12-01

The purpose of this study is to analyse Iranian scientific publications in the neuroscience subfields by librarians and neuroscientists, using Science Citation Index Expanded (SCIE) via Web of Science data over the period, 2002-2008. Data were retrieved from the SCIE. Data were collected from the 'subject area' of the database and classified by neuroscience experts into 14 subfields. To identify the citation patterns, we applied the 'impact factor' and the 'number of publication'. Data were also analysed using HISTCITE, Excel 2007 and SPSS. Seven hundred and thirty-four papers have been published by Iranian between 2002 and 2008. Findings showed a growing trend of neuroscience papers in the last 3 years with most papers (264) classified in the neuropharmacology subfield. There were fewer papers in neurohistory, psychopharmacology and artificial intelligence. International contributions of authors were mostly in the neurology subfield, and 'Collaboration Coefficient' for the neuroscience subfields in Iran was 0.686 which is acceptable. Most international collaboration between Iranians and developed countries was from USA. Eighty-seven percent of the published papers were in journals with the impact factor between 0 and 4; 25% of papers were published by the researchers affiliated to Tehran University of Medical Sciences. Progress of neuroscience in Iran is mostly seen in the neuropharmacology and the neurology subfields. Other subfields should also be considered as a research priority by health policymakers. As this study was carried out by the collaboration of librarians and neuroscientists, it has been proved valuable for both librarians and policymakers. This study may be encouraging for librarians from other developing countries. © 2012 The authors. Health Information and Libraries Journal © 2012 Health Libraries Group.

Paper Punch Tape

CERN Multimedia

Physicists coded and recorded their programs through series of holes on punch paper tape or on punched cards. It was popular in the 1970s due to its high throughput speed and low cost, paper tape was one of the original data storage methods for computers. Information was encoded in the distinct pattern of holes punched in the paper; the paper itself was oiled to facilitate being run through the reading mechanism and to prevent tears due to brittleness. Though the paper was cheap, it had low storage capacity (only a few dozen kilobytes per roll) and the machinery involved in punching the holes was quite expensive. Higher capacity alternatives, such as magnetic tape, has get developped.

Strength Assessment of Controlled Low Strength Materials (CLSM) Utilizing Recycled Concrete Aggregate and Waste Paper Sludge Ash

OpenAIRE

Ridzuan, Ahmad Ruslan Mohd; Fauzi, Mohd Azrizal; Ghazali, Ezliana; Arshad, Mohd Fadzil; Fauzi, Mohd Afiq; Mohd Fauzi, Mohd Afiq

2013-01-01

This paper studies the strength development of low-strength material (CLSM) is controlled by using waste paper sludge ash (WPSA) in CLSM mixtures without adding Portland cement. Series of four (4) compounds which is the CLSM containing 5%, 10%, 20% and 30% of waste paper sludge ash (WPSA) as a substitute for Portland cement. CLSM cubes the sizes of 100mm x 100mm x 100mm compressive strength were tested at age 7, 14 and 28days. It was found that this activity contributes to strength developmen...

Debris disks as signposts of terrestrial planet formation. II. Dependence of exoplanet architectures on giant planet and disk properties

Science.gov (United States)

Raymond, S. N.; Armitage, P. J.; Moro-Martín, A.; Booth, M.; Wyatt, M. C.; Armstrong, J. C.; Mandell, A. M.; Selsis, F.; West, A. A.

2012-05-01

We present models for the formation of terrestrial planets, and the collisional evolution of debris disks, in planetary systems that contain multiple marginally unstable gas giants. We previously showed that in such systems, the dynamics of the giant planets introduces a correlation between the presence of terrestrial planets and cold dust, i.e., debris disks, which is particularly pronounced at λ ~ 70 μm. Here we present new simulations that show that this connection is qualitatively robust to a range of parameters: the mass distribution of the giant planets, the width and mass distribution of the outer planetesimal disk, and the presence of gas in the disk when the giant planets become unstable. We discuss how variations in these parameters affect the evolution. We find that systems with equal-mass giant planets undergo the most violent instabilities, and that these destroy both terrestrial planets and the outer planetesimal disks that produce debris disks. In contrast, systems with low-mass giant planets efficiently produce both terrestrial planets and debris disks. A large fraction of systems with low-mass (M ≲ 30 M⊕) outermost giant planets have final planetary separations that, scaled to the planets' masses, are as large or larger than the Saturn-Uranus and Uranus-Neptune separations in the solar system. We find that the gaps between these planets are not only dynamically stable to test particles, but are frequently populated by planetesimals. The possibility of planetesimal belts between outer giant planets should be taken into account when interpreting debris disk SEDs. In addition, the presence of ~ Earth-mass "seeds" in outer planetesimal disks causes the disks to radially spread to colder temperatures, and leads to a slow depletion of the outer planetesimal disk from the inside out. We argue that this may explain the very low frequency of >1 Gyr-old solar-type stars with observed 24 μm excesses. Our simulations do not sample the full range of

Contributions of Skinner's Theory of Verbal Behaviour to Language Interventions for Children with Autism Spectrum Disorders

Science.gov (United States)

Johnson, Gaige; Kohler, Kelly; Ross, Denise

2017-01-01

The purpose of the current paper is to describe the impact of applied behaviour analysis on language treatment for children with autism spectrum disorders (ASDs) diagnoses. Specifically, this paper will describe Skinner's theory of verbal behaviour and its contributions to evidence-based treatments for communication deficits among individuals with…

Malaysia; Background Paper

OpenAIRE

International Monetary Fund

1996-01-01

This Background Paper on Malaysia examines developments and trends in the labor market since the mid-1980s. The paper describes the changes in the employment structure and the labor force. It reviews wages and productivity trends and their effects on unit labor cost. The paper highlights that Malaysia’s rapid growth, sustained since 1987, has had a major impact on the labor market. The paper outlines the major policy measures to address the labor constraints. It also analyzes Malaysia’s recen...

Papers on topology Analysis Situs and its five supplements

CERN Document Server

Poincaré, Henri

2010-01-01

These famous papers, with their characteristic mixture of deep insight and inevitable confusion, are here presented complete and in English for the first time, with a commentary by their translator, John Stillwell, that guides the reader into the heart of the subject. One of the finest works of one of the great mathematicians is now available anew for students and experts alike. -Jeremy Gray The AMS and John Stillwell have made an important contribution to the mathematics literature in this translation of Poincaré. For many of us, these great papers on the foundations of topology are given greater clarity in English. Moreover, reading Poincaré here illustrates the ultimate in research by successive approximations (akin to my own way of mathematical thinking). - Stephen Smale I am a proud owner of the original complete works in green leather in French bought for a princely sum in Paris around 1975. I have read them extensively, and often during topology lectures I refer to parts of these works. I am happy th...

CALL FOR PAPERS: Special cluster in Biomedical Optics: honouring Professor Valery Tuchin, Saratov University

Science.gov (United States)

Wang, Ruikang K.; Priezzhev, Alexander; Fantini, Sergio

2004-07-01

To honour Professor Valery Tuchin, one of the pioneers in biomedical optics, Journal of Physics D: Applied Physics invites manuscript submissions on topics in biomedical optics, for publication in a Special section in May 2005. Papers may cover a variety of topics related to photon propagation in turbid media, spectroscopy and imaging. This Special cluster will reflect the diversity, breadth and impact of Professor Tuchin's contributions to the field of biomedical optics over the course of his distinguished career. Biomedical optics is a recently emerged discipline providing a broad variety of optical techniques and instruments for diagnostic, therapeutic and basic science applications. Together with contributions from other pioneers in the field, Professor Tuchin's work on fundamental and experimental aspects in tissue optics contributed enormously to the formation of this exciting field. Although general submissions in biomedical optics are invited, the Special cluster Editors especially encourage submissions in areas that are explicitly or implicitly influenced by Professor Tuchin's contributions to the field of biomedical optics. Manuscripts submitted to this Special cluster of Journal of Physics D: Applied Physics will be refereed according to the normal criteria and procedures of the journal, in accordance with the following schedule: Deadline for receipt of contributed papers: 31 November 2004 Deadline for acceptance and completion of refereeing process: 28 February 2005 Publication of special issue: May 2005 Please submit your manuscript electronically to jphysd@iop.org or via the Web site at www.iop.org/Journals. Otherwise, please send a copy of your typescript, a set of original figures and a cover letter to: The Publishing Administrator, Journal of Physics D: Applied Physics, Institute of Physics Publishing, Dirac House, Temple Back, Bristol BS1 6BE, United Kingdom. Further information on how to submit may be obtained upon request by e-mailing the

Ettore Majorana scientific papers. On occasion of the centenary of his birth

International Nuclear Information System (INIS)

Bassani, G.F.

2006-01-01

With this volume the Italian Physical Society presents a collection of Ettore Majorana's scientific papers (note scientifiche) in the original language and, for the first time - with three exceptions - translated into English. Each paper is then followed by a comment (in English) of an expert in the scientific field. Contributors to the comments are Ennio Arimondo, Nicola Cabibbo, Massimo Inguscio, Luciano Maiani, Rosario Nunzio Mantegna, Francesco Minardi, Luigi Radicati di Brozolo and Antonio Sasso. A century after his birth Ettore Majorana is rightfully considered one of the greatest physicists of the first half of the last century. This volume will be of interest to the specialists of the History of Science and to the physicists concerned with problems related to Majorana's contributions. (orig.)

Radiation degration and the subsequent enzymatic hydrolysis of waste papers

International Nuclear Information System (INIS)

Kamakura, M.; Kaetsu, I.

1982-01-01

In recent years, many methods have been proposed for the hydrolysis of waste cellulose to utilize it as a new source of alcohol. Because it is difficult to hydrolyze waste cellulosic materials effectivley with an enzyme, the effects of preirradiating waste papers on subsequent enzymatic hydrolysis was studied. Preirradiation (x rays from 60 Co) accelerated the hydrolysis rate of newspaper by cellulase and the reducing-sugar yield increased with increasing irradiation dose. It is thought that preirradiation probably contributes to loosening and releasing the compactly entangled structure of cellulose and lignin in the materials by radiation degradation

How directional mobility affects coexistence in rock-paper-scissors models

Science.gov (United States)

Avelino, P. P.; Bazeia, D.; Losano, L.; Menezes, J.; de Oliveira, B. F.; Santos, M. A.

2018-03-01

This work deals with a system of three distinct species that changes in time under the presence of mobility, selection, and reproduction, as in the popular rock-paper-scissors game. The novelty of the current study is the modification of the mobility rule to the case of directional mobility, in which the species move following the direction associated to a larger (averaged) number density of selection targets in the surrounding neighborhood. Directional mobility can be used to simulate eyes that see or a nose that smells, and we show how it may contribute to reduce the probability of coexistence.

Paper microzone plates.

Science.gov (United States)

Carrilho, Emanuel; Phillips, Scott T; Vella, Sarah J; Martinez, Andres W; Whitesides, George M

2009-08-01

This paper describes 96- and 384-microzone plates fabricated in paper as alternatives to conventional multiwell plates fabricated in molded polymers. Paper-based plates are functionally related to plastic well plates, but they offer new capabilities. For example, paper-microzone plates are thin (approximately 180 microm), require small volumes of sample (5 microL per zone), and can be manufactured from inexpensive materials ($0.05 per plate). The paper-based plates are fabricated by patterning sheets of paper, using photolithography, into hydrophilic zones surrounded by hydrophobic polymeric barriers. This photolithography used an inexpensive formulation photoresist that allows rapid (approximately 15 min) prototyping of paper-based plates. These plates are compatible with conventional microplate readers for quantitative absorbance and fluorescence measurements. The limit of detection per zone loaded for fluorescence was 125 fmol for fluorescein isothiocyanate-labeled bovine serum albumin, and this level corresponds to 0.02 the quantity of analyte per well used to achieve comparable signal-to-noise in a 96-well plastic plate (using a solution of 25 nM labeled protein). The limits of detection for absorbance on paper was approximately 50 pmol per zone for both Coomassie Brilliant Blue and Amaranth dyes; these values were 0.4 that required for the plastic plate. Demonstration of quantitative colorimetric correlations using a scanner or camera to image the zones and to measure the intensity of color, makes it possible to conduct assays without a microplate reader.

The evolution of Candu fuel cycles and their potential contribution to world peace

International Nuclear Information System (INIS)

Whitlock, J.

2000-01-01

This paper describes how several factors, including Canada's early focus on heavy-water reactor technology, limited heavy-industry infrastructure, and desire for both technological autonomy and energy self- sufficiency, contributed to the creation of the first Candu reactor in 1962. (author)

Contributions to the 1st Int. Conference on new laser technologies and applications

International Nuclear Information System (INIS)

1988-01-01

The report contains ten papers contributing to the first International conference on new laser technologies held in Olympia from 19 to 23 June 1988. They represent the activities in this field carried out by the ENEA Department of Basic Technologies

Ergonomics Contribution in Maintainability

Science.gov (United States)

Teymourian, Kiumars; Seneviratne, Dammika; Galar, Diego

2017-09-01

The objective of this paper is to describe an ergonomics contribution in maintainability. The economical designs, inputs and training helps to increase the maintainability indicators for industrial devices. This analysis can be helpful, among other cases, to compare systems, to achieve a better design regarding maintainability requirements, to improve this maintainability under specific industrial environment and to foresee maintainability problems due to eventual changes in a device operation conditions. With this purpose, this work first introduces the notion of ergonomics and human factors, maintainability and the implementation of assessment of human postures, including some important postures to perform maintenance activities. A simulation approach is used to identify the critical posture of the maintenance personnel and implements the defined postures with minimal loads on the personnel who use the equipment in a practical scenario. The simulation inputs are given to the designers to improve the workplace/equipment in order to high level of maintainability. Finally, the work concludes summarizing the more significant aspects and suggesting future research.

Contributions of Islamic Civilization to The Mathematics Development

Directory of Open Access Journals (Sweden)

Liya Khaulah Asy-Syaimaa' Hussain

2017-12-01

Full Text Available The development of Islamic civilization goes hand in hand with physical and spiritual development. This development can be highlighted since the beginning of the golden age of Islam that witnessed the development of knowledge by Muslims scholars in various disciplines, including mathematics. The discourse in mathematical science only involves numbers, letters, and formulas. Muslims scholars took them as instruments to manifest the greatest of God. This paper investigates the contributions of Muslim scholars in Mathematics. The method of this study is qualitative through literature review. The resulting study found that the Quran became a source of inspiration to Muslim scholars in mathematics that form the branch of knowledge such as number theory, arithmetic, algebra, and geometry. This paper also promotes Islamization of Knowledge and its necessity to solve current Muslim world’s educational problems.

Paper based electronics platform

KAUST Repository

Nassar, Joanna Mohammad; Sevilla, Galo Andres Torres; Hussain, Muhammad Mustafa

2017-01-01

A flexible and non-functionalized low cost paper-based electronic system platform fabricated from common paper, such as paper based sensors, and methods of producing paper based sensors, and methods of sensing using the paper based sensors

Transatlantic Dialogue: A Research Exchange; Papers from a Joint Conference (Leeds, England, July 11-13, 1988).

Science.gov (United States)

Zukas, Miriam, Ed.

Over 90 papers focus on adult education research. Selected titles include "Karl Marx's Theoretical Contributions to Radical Adult Education" (Allman, Wallis); "Educating Educators" (Armstrong); "Comparative Study of Philosophical Foundations of Adult Education in China and United States" (Bao); "Ethical Value Dilemmas of Professional Adult…

75 FR 34388 - Employee Contribution Elections and Contribution Allocations

Science.gov (United States)

2010-06-17

... contributions equal to 3 percent of the employee's basic pay will be deducted from his or her pay and... employees who are rehired after a separation in service of 31 or more calendar days and who are eligible to participate in the TSP will automatically have 3 percent of their basic pay contributed to the TSP, unless...

LCA of an ice cream cup of polyethylene coated paper: how does the choice of the end-of-life affect the results?

Science.gov (United States)

Buccino, Carla; Ferrara, Carmen; Malvano, Carmela; De Feo, Giovanni

2017-11-07

This study presents an evaluation of the environmental performance of an ice cream cup made of polyethylene (PE)/paper laminate using a life cycle assessment approach 'from cradle to grave'. Two opposite alternative disposal scenarios, as well as their intermediate combinations, were considered: 100% incineration and 100% landfilling. The environmental impacts were calculated using the EPD 2013 evaluation method since the study was developed in an Environmental Product Declaration perspective as well as the method ReCiPe 2008 H at the endpoint level. PE/paper laminate production was the most impactful process since it provided the highest contribution to total impacts in four of six impact categories considered. Ice cream cup production was the second impactful process. The 100% incineration scenario provided negligible contribution to life cycle total impact for all impact categories; while considering the landfilling scenario, the percentage contributions to the total impact provided by the end-of-life phase increased considerably, until to be comparable to the contributions provided by the production processes of the PE/paper laminate and the ice cream cup. The obtained results highlighted that different disposal scenarios can affect significantly the conclusions of a study. At the endpoint level, incineration was more environmentally sound than landfilling for all the ReCiPe damage categories.

TERRESTRIAL PLANET FORMATION DURING THE MIGRATION AND RESONANCE CROSSINGS OF THE GIANT PLANETS

International Nuclear Information System (INIS)

Lykawka, Patryk Sofia; Ito, Takashi

2013-01-01

The newly formed giant planets may have migrated and crossed a number of mutual mean motion resonances (MMRs) when smaller objects (embryos) were accreting to form the terrestrial planets in the planetesimal disk. We investigated the effects of the planetesimal-driven migration of Jupiter and Saturn, and the influence of their mutual 1:2 MMR crossing on terrestrial planet formation for the first time, by performing N-body simulations. These simulations considered distinct timescales of MMR crossing and planet migration. In total, 68 high-resolution simulation runs using 2000 disk planetesimals were performed, which was a significant improvement on previously published results. Even when the effects of the 1:2 MMR crossing and planet migration were included in the system, Venus and Earth analogs (considering both orbits and masses) successfully formed in several runs. In addition, we found that the orbits of planetesimals beyond a ∼ 1.5-2 AU were dynamically depleted by the strengthened sweeping secular resonances associated with Jupiter's and Saturn's more eccentric orbits (relative to the present day) during planet migration. However, this depletion did not prevent the formation of massive Mars analogs (planets with more than 1.5 times Mars's mass). Although late MMR crossings (at t > 30 Myr) could remove such planets, Mars-like small mass planets survived on overly excited orbits (high e and/or i), or were completely lost in these systems. We conclude that the orbital migration and crossing of the mutual 1:2 MMR of Jupiter and Saturn are unlikely to provide suitable orbital conditions for the formation of solar system terrestrial planets. This suggests that to explain Mars's small mass and the absence of other planets between Mars and Jupiter, the outer asteroid belt must have suffered a severe depletion due to interactions with Jupiter/Saturn, or by an alternative mechanism (e.g., rogue super-Earths)

Rapid, dynamic segregation of core forming melts: Results from in-situ High Pressure- High Temperature X-ray Tomography

Science.gov (United States)

Watson, H. C.; Yu, T.; Wang, Y.

2011-12-01

The timing and mechanisms of core formation in the Earth, as well as in Earth-forming planetesimals is a problem of significant importance in our understanding of the early evolution of terrestrial planets . W-Hf isotopic signatures in meteorites indicate that core formation in small pre-differentiated planetesimals was relatively rapid, and occurred over the span of a few million years. This time scale is difficult to achieve by percolative flow of the metallic phase through a silicate matrix in textural equilibrium. It has been suggested that during this active time in the early solar system, dynamic processes such as impacts may have caused significant deformation in the differentiating planetesimals, which could lead to much higher permeability of the core forming melts. Here, we have measured the change in permeability of core forming melts in a silicate matrix due to deformation. Mixtures of San Carlos olivine and FeS close to the equilibrium percolation threshold (~5 vol%FeS) were pre-synthesized to achieve an equilibrium microstructure, and then loaded into the rotational Drickamer apparatus at GSE-CARS, sector 13-BMD, at the Advanced Photon Source (Argonne National Laboratory). The samples were subsequently pressed to ~2GPa, and heated to 1100°C. Alternating cycles of rotation to collect X-ray tomography images, and twisting to deform the sample were conducted until the sample had been twisted by 1080°. Qualitative and quantitative analyses were performed on the resulting 3-dimensional x-ray tomographic images to evaluate the effect of shear deformation on permeability and migration velocity. Lattice-Boltzmann simulations were conducted, and show a marked increase in the permeability with increasing deformation, which would allow for much more rapid core formation in planetesimals.

The Importance of the Foreign Language Learning Contributing to World Peace

Science.gov (United States)

Sahin, Yusuf

2011-01-01

The aim of this paper is to determine the elements which hinder peace, and emphasize the importance of the contribution of foreign language learning to international peace. Language affects the thought and behavior of human beings. The attitude of a person knowing more than one language of a position is not the same as a person not knowing a…

Nordic Internationalists' Contribution to the Field of Comparative and International Education

Science.gov (United States)

Genova, Teodora

2016-01-01

This paper stems from a PhD dissertation research focusing on the Nordic representatives' contribution to the field of comparative and international education (CIE) since the middle of the 20th century to the present days. Following the idea of the clear-cut distinction between the two component parts of the field in the region in question, the…

The contribution of nuclear science and technology to sustainable development

International Nuclear Information System (INIS)

Hardy, C.J.

1997-01-01

The United Nations and many individual States and organisations have given increasing attention to the topic of sustainable development in recent years. This has arisen because of concerns about the increasing population of the planet, increasing levels of carbon dioxide in the atmosphere and other pollutants in the biosphere, and the need for increasing amounts of food, water and energy. The paper will use the recent reports of these organisations as background and give an overview of the perceived problems needed to be addressed in the 21st Century to allow sustainable development. The ways in which nuclear science and technology is already contributing to the solution of these problems will then be summarised and comments made on how it can contribute even more in the future

Toward Wearable Energy Storage Devices: Paper-Based Biofuel Cells based on a Screen-Printing Array Structure.

Science.gov (United States)

Shitanda, Isao; Momiyama, Misaki; Watanabe, Naoto; Tanaka, Tomohiro; Tsujimura, Seiya; Hoshi, Yoshinao; Itagaki, Masayuki

2017-10-01

A novel paper-based biofuel cell with a series/parallel array structure has been fabricated, in which the cell voltage and output power can easily be adjusted as required by printing. The output of the fabricated 4-series/4-parallel biofuel cell reached 0.97±0.02 mW at 1.4 V, which is the highest output power reported to date for a paper-based biofuel cell. This work contributes to the development of flexible, wearable energy storage device.

Other relevant papers in physical oceanography

International Nuclear Information System (INIS)

Nyffeler, F.

1989-01-01

During the past few years, significant progress has occurred in the field of physical oceanography partly as a consequence of developing cooperation and international participation in well-coordinated ocean research programmes. Although these programs were not designed specifically to address CRESP problems, many have proved to be directly relevant to CRESP objectives. For example, MODE, POLYMODE, and Tourbillon were intensive site-specific experiments that included studies of dispersion processes throughout the water column. NOAMP and GME were also site specific, involved the entire water column, and even stressed near-bottom and suspended-sediment processes. Others, (e.g., WOCE) are larger in scope and include extensive observations of the general circulation of entire ocean basins. As a whole, they contribute immensely to improving the data base for exchange and transport processes and thereby for the verification and validation of both regional-scale and general-circulation ocean models. That, in turn, is directly relevant to radiological assessments. Selected papers deriving from experiments such as these are discussed and referenced below

GEOGRAPHIC INFORMATION SYSTEMS AND APPLIED ECONOMICS: AN INITIAL DISCUSSION OF POTENTIAL APPLICATIONS AND CONTRIBUTIONS

OpenAIRE

Taupier, Richard; Willis, Cleve E.

1994-01-01

Geographic Information Systems (GIS) are becoming increasingly important to virtually all of the natural and social sciences. Applied economists will find that GIS can make valuable contributions to many of the problems with which they are concerned. Moreover, a great deal of the science behind GIS technology would benefit from the contributions of applied economists. This paper presents some initial suggestions for the ways in which GIS may be important to economics and the GIS related issue...

Vibration analysis of paper machine's asymmetric tube roll supported by spherical roller bearings

Science.gov (United States)

Heikkinen, Janne E.; Ghalamchi, Behnam; Viitala, Raine; Sopanen, Jussi; Juhanko, Jari; Mikkola, Aki; Kuosmanen, Petri

2018-05-01

This paper presents a simulation method that is used to study subcritical vibrations of a tube roll in a paper machine. This study employs asymmetric 3D beam elements based on the Timoshenko beam theory. An asymmetric beam model accounts for varying stiffness and mass distributions. Additionally, a detailed rolling element bearing model defines the excitations arising from the set of spherical roller bearings at both ends of the rotor. The results obtained from the simulation model are compared against the results from the measurements. The results indicate that the waviness of the bearing rolling surfaces contributes significantly to the subcritical vibrations while the asymmetric properties of the tube roll have only a fractional effect on the studied vibrations.

EDITORIAL: Special issue containing papers presented at the 12th International Workshop on H-mode Physics and Transport Barriers Special issue containing papers presented at the 12th International Workshop on H-mode Physics and Transport Barriers

Science.gov (United States)

Hahm, T. S.

2010-06-01

The 12th International Workshop on H-mode Physics and Transport Barriers was held at the Princeton Plasma Physics Laboratory, Princeton, New Jersey, USA between September 30 and October 2, 2009. This meeting was the continuation of a series of previous meetings which was initiated in 1987 and has been held bi-annually since then. Following the recent tradition at the last few meetings, the program was sub- divided into six sessions. At each session, an overview talk was presented, followed by two or three shorter oral presentations which supplemented the coverage of important issues. These talks were followed by discussion periods and poster sessions of contributed papers. The sessions were: Physics of Transition to/from Enhanced Confinement Regimes, Pedestal and Edge Localized Mode Dynamics, Plasma Rotation and Momentum Transport, Role of 3D Physics in Transport Barriers, Transport Barriers: Theory and Simulations and High Priority ITER Issues on Transport Barriers. The diversity of the 90 registered participants was remarkable, with 22 different nationalities. US participants were in the majority (36), followed by Japan (14), South Korea (7), and China (6). This special issue of Nuclear Fusion consists of a cluster of 18 accepted papers from submitted manuscripts based on overview talks and poster presentations. The paper selection procedure followed the guidelines of Nuclear Fusion which are essentially the same as for regular articles with an additional requirement on timeliness of submission, review and revision. One overview paper and five contributed papers report on the H-mode pedestal related results which reflect the importance of this issue concerning the successful operation of ITER. Four papers address the rotation and momentum transport which play a crucial role in transport barrier physics. The transport barrier transition condition is the main focus of other four papers. Finally, four additional papers are devoted to the behaviour and control of

Contributions of research Reactors in science and technology

International Nuclear Information System (INIS)

Butt, N.M.; Bashir, J.

1992-12-01

In the present paper, after defining a research reactor, its basic constituents, types of reactors, their distribution in the world, some typical examples of their uses are given. Particular emphasis in placed on the contribution of PARR-I (Pakistan Research Reactor-I), the 5 MW Swimming Pool Research reactor which first became critical at the Pakistan Institute of Nuclear Science and Technology (PINSTECH) in Dec. 1965 and attained its full power in June 1966. This is still the major research facility at PINSTECH for research and development. (author)

Corporate Foresight: Antecedents and Contributions to Innovation Performance

DEFF Research Database (Denmark)

Jissink, Tymen; Rohrbeck, René; Huizingh, Eelko K.R.E.

In this paper we explore the current understanding of corporate foresight as a system for creating understandings of possible futures, factors that drive the need and usage of corporate foresight as well as how corporate foresight can contribute to a firm’s innovation performance. Drawing upon...... still limited research on corporate foresight, we find that 1) there is still little consensus on the concept of corporate foresight, 2) the need for corporate foresight can originate from both internal and external factors, and 3) innovation performance can be positively influenced by a number...

The Contribution of Qualitative Methods for Identifying the Educational Needs of Adults

Science.gov (United States)

Boz, Hayat; Dagli, Yakup

2017-01-01

This study addresses the contribution of applying qualitative research methods for identifying the educational activities planned for adults. The paper is based on the experience gained during in-depth interviews with 39 elderly and 33 middle-aged participants, by purposive sampling method and maximum variation technique, within a needs analysis…

Contribution of the 'safeguarded' to the development of safeguards

International Nuclear Information System (INIS)

Anderson, A.R.

1977-01-01

The development of an efficient system of international safeguards requires close and detailed interaction between the safeguarding authority and those being safeguarded, i.e. the plant operator and the State System to which he belongs. Such interaction is found in other control systems but the degree of international collaboration involved in safeguards is perhaps unique and it is valuable to review and analyse the contributions which have arisen from prudent management considerations. The familiar ''Blue Book'' (INFCIRC 153) recognizes clearly the need for an effective State's System of accounting for and control of nuclear materials as a necessary pre-requisite for the development and implementation of an effective IAEA system of safeguards. It is therefore helpful to summarize the relevant contributions from the 'safeguarded' in terms of the components of the State's System specified in paragraph 32 of the Blue Book. This paper reviews the continuing contributions stemming from plant and national experience, with particular emphasis on the development of measurement systems and physical inventory procedures relevant to safeguards. Attention is also drawn to those areas where the specific objectives of IAEA Safeguards lead to requirements additional to those required for management purposes. (author)

Supergravity contributions to inflation in models with non-minimal coupling to gravity

Energy Technology Data Exchange (ETDEWEB)

Das, Kumar; Dutta, Koushik [Theory Division, Saha Institute of Nuclear Physics, 1/AF Saltlake, Kolkata 700064 (India); Domcke, Valerie, E-mail: kumar.das@saha.ac.in, E-mail: valerie.domcke@apc.univ-paris7.fr, E-mail: koushik.dutta@saha.ac.in [AstroParticule et Cosmologie (APC), Paris Centre for Cosmological Physics (PCCP), Université Paris Diderot, 75013 Paris (France)

2017-03-01

This paper provides a systematic study of supergravity contributions relevant for inflationary model building in Jordan frame supergravity. In this framework, canonical kinetic terms in the Jordan frame result in the separation of the Jordan frame scalar potential into a tree-level term and a supergravity contribution which is potentially dangerous for sustaining inflation. We show that if the vacuum energy necessary for driving inflation originates dominantly from the F-term of an auxiliary field (i.e. not the inflaton), the supergravity corrections to the Jordan frame scalar potential are generically suppressed. Moreover, these supergravity contributions identically vanish if the superpotential vanishes along the inflationary trajectory. On the other hand, if the F-term associated with the inflaton dominates the vacuum energy, the supergravity contributions are generically comparable to the globally supersymmetric contributions. In addition, the non-minimal coupling to gravity inherent to Jordan frame supergravity significantly impacts the inflationary model depending on the size and sign of this coupling. We discuss the phenomenology of some representative inflationary models, and point out the relation to the recently much discussed cosmological 'attractor' models.

Supergravity contributions to inflation in models with non-minimal coupling to gravity

International Nuclear Information System (INIS)

Das, Kumar; Dutta, Koushik; Domcke, Valerie

2017-01-01

This paper provides a systematic study of supergravity contributions relevant for inflationary model building in Jordan frame supergravity. In this framework, canonical kinetic terms in the Jordan frame result in the separation of the Jordan frame scalar potential into a tree-level term and a supergravity contribution which is potentially dangerous for sustaining inflation. We show that if the vacuum energy necessary for driving inflation originates dominantly from the F-term of an auxiliary field (i.e. not the inflaton), the supergravity corrections to the Jordan frame scalar potential are generically suppressed. Moreover, these supergravity contributions identically vanish if the superpotential vanishes along the inflationary trajectory. On the other hand, if the F-term associated with the inflaton dominates the vacuum energy, the supergravity contributions are generically comparable to the globally supersymmetric contributions. In addition, the non-minimal coupling to gravity inherent to Jordan frame supergravity significantly impacts the inflationary model depending on the size and sign of this coupling. We discuss the phenomenology of some representative inflationary models, and point out the relation to the recently much discussed cosmological 'attractor' models.

The physics of paper

International Nuclear Information System (INIS)

Alava, Mikko; Niskanen, Kaarlo

2006-01-01

Paper is a material known to everybody. It has a network structure consisting of wood fibres that can be mimicked by cooking a portion of spaghetti and pouring it on a plate, to form a planar assembly of fibres that lie roughly horizontal. Real paper also contains other constituents added for technical purposes. This review has two main lines of thought. First, in the introductory part, we consider the physics that one encounters when 'using' paper, an everyday material that exhibits the presence of disorder. Questions arise, for instance, as to why some papers are opaque and others translucent, some are sturdy and others sloppy, some readily absorb drops of liquid while others resist the penetration of water. The mechanical and rheological properties of paper and paperboard are also interesting. They are inherently dependent on moisture content. In humid conditions paper is ductile and soft, in dry conditions brittle and hard. In the second part we explain in more detail research problems concerned with paper. We start with paper structure. Paper is made by dewatering a suspension of fibres starting from very low content of solids. The processes of aggregation, sedimentation and clustering are familiar from statistical mechanics. Statistical growth models or packing models can simulate paper formation well and teach a lot about its structure. The second research area that we consider is the elastic and viscoelastic properties and fracture of paper and paperboard. This has traditionally been the strongest area of paper physics. There are many similarities to, but also important differences from, composite materials. Paper has proved to be convenient test material for new theories in statistical fracture mechanics. Polymer physics and memory effects are encountered when studying creep and stress relaxation in paper. Water is a 'softener' of paper. In humid conditions, the creep rate of paper is much higher than in dry conditions. The third among our topics is the

Analysing countries' contribution to climate change: scientific and policy-related choices

International Nuclear Information System (INIS)

Elzen, Michel den; Fuglestvedt, Jan; Hoehne, Niklas; Trudinger, Cathy; Lowe, Jason; Matthews, Ben; Romstad, Bard; Pires de Campos, Christiano; Andronova, Natalia

2005-01-01

This paper evaluates the influence of different policy-related and scientific choices on the calculated regional contributions to global climate change (the 'Brazilian Proposal'). Policy-related choices include the time period of emissions, the mix of greenhouse gases and different indicators of climate change impacts. The scientific choices include historical emissions and model representations of the climate system. We generated and compared results of several simple climate models. We find that the relative contributions of different nations to global climate change-from emissions of greenhouse gases alone-are quite robust, despite the varying model complexity and differences in calculated absolute changes. For the default calculations, the average calculated contributions to the global mean surface temperature increase in 2000 are about 40% from OECD, 14% from Eastern Europe and Former Soviet Union, 24% from Asia and 22% from Africa and Latin America. Policy-related choices, such as time period of emissions, climate change indicator and gas mix generally have larger influence on the results than scientific choices. More specifically, choosing a later attribution start date (1990 instead of 1890) for historical emissions, decreases the contributions of regions that started emitting early, such as the OECD countries by 6 percentage points, whereas it increases the contribution of late emitters such as Asia by 8 percentage points. However, only including the fossil CO 2 emissions instead of the emissions of all Kyoto gases (fossil and land use change), increases the OECD contributions by 21 percentage points and decreases the contribution of Asia by 14 percentage points

Saturn’s Formation and Early Evolution at the Origin of Jupiter’s Massive Moons

Science.gov (United States)

Ronnet, T.; Mousis, O.; Vernazza, P.; Lunine, J. I.; Crida, A.

2018-05-01

The four massive Galilean satellites are believed to have formed within a circumplanetary disk during the last stages of Jupiter’s formation. While the existence of a circum-Jovian disk is supported by hydrodynamic simulations, no consensus exists regarding the origin and delivery mechanisms of the building blocks of the forming satellites. The opening of a gap in the circumsolar disk would have efficiently isolated Jupiter from the main sources of solid material. However, a reservoir of planetesimals should have existed at the outer edge of Jupiter’s gap, where solids were trapped and accumulated over time. Here we show that the formation of Saturn’s core within this reservoir, or its prompt inward migration, allows planetesimals to be redistributed from this reservoir toward Jupiter and the inner Solar System, thereby providing enough material to form the Galilean satellites and to populate the Main Belt with primitive asteroids. We find that the orbit of planetesimals captured within the circum-Jovian disk are circularized through friction with gas in a compact system comparable to the current radial extent of the Galilean satellites. The decisive role of Saturn in the delivery mechanism has strong implications for the occurrence of massive moons around extrasolar giant planets as they would preferentially form around planets within multiple planet systems.

CHAOTIC CAPTURE OF NEPTUNE TROJANS

International Nuclear Information System (INIS)

Nesvorny, David; Vokrouhlicky, David

2009-01-01

Neptune Trojans (NTs) are swarms of outer solar system objects that lead/trail planet Neptune during its revolutions around the Sun. Observations indicate that NTs form a thick cloud of objects with a population perhaps ∼10 times more numerous than that of Jupiter Trojans and orbital inclinations reaching ∼25 deg. The high inclinations of NTs are indicative of capture instead of in situ formation. Here we study a model in which NTs were captured by Neptune during planetary migration when secondary resonances associated with the mean-motion commensurabilities between Uranus and Neptune swept over Neptune's Lagrangian points. This process, known as chaotic capture, is similar to that previously proposed to explain the origin of Jupiter's Trojans. We show that chaotic capture of planetesimals from an ∼35 Earth-mass planetesimal disk can produce a population of NTs that is at least comparable in number to that inferred from current observations. The large orbital inclinations of NTs are a natural outcome of chaotic capture. To obtain the ∼4:1 ratio between high- and low-inclination populations suggested by observations, planetary migration into a dynamically excited planetesimal disk may be required. The required stirring could have been induced by Pluto-sized and larger objects that have formed in the disk.

The Formation of Jupiter, the Jovian Early Bombardment and the Delivery of Water to the Asteroid Belt: The Case of (4) Vesta

Science.gov (United States)

Turrini, Diego; Svetsov, Vladimir

2014-01-01

The asteroid (4) Vesta, parent body of the Howardite-Eucrite-Diogenite meteorites, is one of the first bodies that formed, mostly from volatile-depleted material, in the Solar System. The Dawn mission recently provided evidence that hydrated material was delivered to Vesta, possibly in a continuous way, over the last 4 Ga, while the study of the eucritic meteorites revealed a few samples that crystallized in presence of water and volatile elements. The formation of Jupiter and probably its migration occurred in the period when eucrites crystallized, and triggered a phase of bombardment that caused icy planetesimals to cross the asteroid belt. In this work, we study the flux of icy planetesimals on Vesta during the Jovian Early Bombardment and, using hydrodynamic simulations, the outcome of their collisions with the asteroid. We explore how the migration of the giant planet would affect the delivery of water and volatile materials to the asteroid and we discuss our results in the context of the geophysical and collisional evolution of Vesta. In particular, we argue that the observational data are best reproduced if the bulk of the impactors was represented by 1–2 km wide planetesimals and if Jupiter underwent a limited (a fraction of au) displacement. PMID:25370027

The Formation of Jupiter, the Jovian Early Bombardment and the Delivery of Water to the Asteroid Belt: The Case of (4 Vesta

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Diego Turrini

2014-01-01

Full Text Available The asteroid (4 Vesta, parent body of the Howardite-Eucrite-Diogenite meteorites, is one of the first bodies that formed, mostly from volatile-depleted material, in the Solar System. The Dawn mission recently provided evidence that hydrated material was delivered to Vesta, possibly in a continuous way, over the last 4 Ga, while the study of the eucritic meteorites revealed a few samples that crystallized in presence of water and volatile elements. The formation of Jupiter and probably its migration occurred in the period when eucrites crystallized, and triggered a phase of bombardment that caused icy planetesimals to cross the asteroid belt. In this work, we study the flux of icy planetesimals on Vesta during the Jovian Early Bombardment and, using hydrodynamic simulations, the outcome of their collisions with the asteroid. We explore how the migration of the giant planet would affect the delivery of water and volatile materials to the asteroid and we discuss our results in the context of the geophysical and collisional evolution of Vesta. In particular, we argue that the observational data are best reproduced if the bulk of the impactors was represented by 1–2 km wide planetesimals and if Jupiter underwent a limited (a fraction of au displacement.

Greenhouse gases - an up-date on the contribution of automotive fuels

International Nuclear Information System (INIS)

Williams, M.L.

1992-01-01

This paper examines the contribution to global emissions of greenhouse gases from automotive fuels. The Greenhouse Effect and Climate Change are explained briefly. Data is presented on the global warming potential of automobile emissions, actual measured emission rates and greenhouse gas emissions as CO 2 equivalents. It is concluded that insufficient data exists to assess accurately the contribution of automotive fuel use to all the important greenhouse gases. Over short timescales (say 20 years) low emission technologies do show significant reductions in CO 2 equivalent emissions compared with current technology vehicles. However, in the longer term, fuel economy rather than emissions of non-CO 2 gases, is likely to become the determining factor. (UK)

Spectral Neugebauer-based color halftone prediction model accounting for paper fluorescence.

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Hersch, Roger David

2014-08-20

We present a spectral model for predicting the fluorescent emission and the total reflectance of color halftones printed on optically brightened paper. By relying on extended Neugebauer models, the proposed model accounts for the attenuation by the ink halftones of both the incident exciting light in the UV wavelength range and the emerging fluorescent emission in the visible wavelength range. The total reflectance is predicted by adding the predicted fluorescent emission relative to the incident light and the pure reflectance predicted with an ink-spreading enhanced Yule-Nielsen modified Neugebauer reflectance prediction model. The predicted fluorescent emission spectrum as a function of the amounts of cyan, magenta, and yellow inks is very accurate. It can be useful to paper and ink manufacturers who would like to study in detail the contribution of the fluorescent brighteners and the attenuation of the fluorescent emission by ink halftones.

A retrospective appreciation of Willard Day's contributions to radical behaviorism and the analysis of verbal behavior

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Moore, Jay

1991-01-01

Willard Day's contributions to radical behaviorism are grouped under three headings: (a) an emphasis on the distinction between radical and methodological behaviorism; (b) an emphasis on the interpretation, rather than the prediction and control, of behavior; and (c) an emphasis on the analysis of verbal behavior as a natural, ongoing phenomenon. The paper suggests that the contributions above are listed in ascending order of significance. PMID:22477632

INTERNATIONAL STUDENTS CONTRIBUTION TO BUSINESS SCHOOLS IN THE UK HEIs

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Trevor Uyi OMORUYI

2014-11-01

Full Text Available International students’ contribution to Higher Education Institutions (HEIs tends to be considered from different aspects. There is an inadequate substantiation base that would allow academics, researchers and other stakeholders understand the importance of overseas students in the UK Business Schools. This paper investigates the contribution of international students to Business School in the UK HEIs. The research was exploratory and part of a bigger project on how and why Business Schools in the UK use Relationship Marketing to retain international students. It employed semi-structured interviews with 18 members of staff from four Business Schools in the North of England. Findings indicate that international students’ definition tends to differ amongst staff members within the Business Schools. Business Schools’ management perceive overseas students as an integral part of their institutions, especially as their overall contributions cannot be over-emphasised. The sample size and use of semi-structured interviews, as a single data gathering strategy, does not allow broad generalisation of findings. The obtained evidence can still be used as a platform for further research in this area.

Political science, public administration, and natural hazards: contributions and connections

Science.gov (United States)

Lindquist, E.

2009-04-01

The connection between the natural and social sciences has become stronger, and has increasingly been recognized as a vital component in the area of natural hazards research. Moving applied natural hazards research into the public policy or administration realm is not often easy, or effective. An improved understanding of the connection between the natural and social sciences can assist in this process and result in better public policy, acceptance from the public for these policies, and a safer and better educated public. This paper will present initial findings from a larger data set on natural hazards and social science research. Specifically we will review the current contribution of the formal academic disciplines of political science and public administration within recent natural hazards-related scholarship. The general characteristics of the contributions (e.g. coauthored, interdisciplinary, etc.), specific theories and methods being applied, and the types of natural hazards being scrutinized by these related fields will be assessed. In conclusion we will discuss future contributions and areas for potential collaboration between the natural and social sciences in the area of natural hazards research.

Does Islamic Banking Contribute to Economic Development? Evidence from Malaysia

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Hafas Furqani

2008-08-01

Full Text Available Does Islamic banking contribute to the economic development of a country? In what way Islamic banking contribute to the economic development? Are the main question might be asked to examine the viability of Islamic banking to the economic development. This paper attempts to answer those questions by examining the dynamic interactions between Islamic banking and economic development of Malaysia by employing the Cointegration test and Vector Error Model (VECM to see whether the Islamic financial system contributes to the economic development and economic development that contribute to the transformation of the operation of the Islamic financial system in the longrun. We use time series data of total Islamic bank financing (IB financing and real GDP per capita (RGDP, fixed investment (GFCF, and trade activities (TRADE to represent real economic sectors. We found that in the short-run only fixed investment that granger cause Islamic bank to develop for 1997:1-2005:4. Where as in the long-run, there is evidence of a bidirectional relationship between Islamic bank and fixed investment and there is evidence to support ‘demand following’ hypothesis of GDP and Islamic bank, where increase in GDP causes Islamic banking to develop and not vice versa. Islamic banking is also found to have less contribution to the international trade in the form of export and import of goods and services.Keywords: Islamic banking, economic growth, Malaysia, VECM

The Contributions of Physical Activity and Fitness to Optimal Health and Wellness

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Ohuruogu, Ben

2016-01-01

The paper examined the role of physical activity and fitness more especially in the area of disease prevention and control by looking at the major ways by which regular physical activity and fitness contributes to optimal health and wellness. The Surgeor General's Report (1996), stressed that physical inactivity is a national problem which…

Friedrich Dessauer's (1881-1963) contributions to the development of radiotherapy in Turkey

International Nuclear Information System (INIS)

Dinc, Gulten

2007-01-01

Famous physicist Friedrich Dessauer carried out innovative studies in the field of radiotherapy in Turkey where he took refuge escaping from the political situation in Germany before the Second World War. The paper deals with Dessauer's works for the establishment of a radiotherapy institute in Turkey and his contributions to this field

Paper on Designing Costless THz Paper Optics

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A. Siemion

2016-01-01

Full Text Available Designing diffractive optical elements is crucial for efficient development of THz techniques. Here, we consider paper structures and we analyze their advantages and disadvantages in fast prototyping. The discussion about using material parameters like refractive index and absorption coefficient in designing diffractive optical elements is shown. We analyze the influence of phase step mismatch, of attenuation of real structure, and of nonuniform illumination on the efficiency of the structure. All these features result in worsening of the diffraction efficiency but they do not seem to have such significant influence as shadow effect introduced by fast varying zones. Diffractive elements can be designed with very good accordance with experimental results which makes them ideal for possible applications. Paper optics scan be used more for fast prototyping; nevertheless its performance can be increased by placing it inside water protecting foil.

Taxing Meat: Taking Responsibility for One’s Contribution to Antibiotic Resistance

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Giubilini, Alberto; Birkl, Patrick; Douglas, Thomas; Savulescu, Julian; Maslen, Hannah

2018-01-01

Antibiotic use in animal farming is one of the main drivers of antibiotic resistance both in animals and in humans. In this paper we propose that one feasible and fair way to address this problem is to tax animal products obtained with the use of antibiotics. We argue that such tax is supported both by (a) deontological arguments, which are based on the duty individuals have to compensate society for the antibiotic resistance to which they are contributing through consumption of animal products obtained with the use of antibiotics; and (b) a cost-benefit analysis of taxing such animal products and of using revenue from the tax to fund alternatives to use of antibiotics in animal farming. Finally, we argue that such a tax would be fair because individuals who consume animal products obtained with the use of antibiotics can be held morally responsible, i.e. blameworthy, for their contribution to antibiotic resistance, in spite of the fact that each individual contribution is imperceptible. PMID:29515330

Stimulating Contributions to Public Goods through Information Feedback: Some Experimental Results.

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Marco A Janssen

Full Text Available In traditional public good experiments participants receive an endowment from the experimenter that can be invested in a public good or kept in a private account. In this paper we present an experimental environment where participants can invest time during five days to contribute to a public good. Participants can make contributions to a linear public good by logging into a web application and performing virtual actions. We compared four treatments, with different group sizes and information of (relative performance of other groups. We find that information feedback about performance of other groups has a small positive effect if we control for various attributes of the groups. Moreover, we find a significant effect of the contributions of others in the group in the previous day on the number of points earned in the current day. Our results confirm that people participate more when participants in their group participate more, and are influenced by information about the relative performance of other groups.