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Добірка наукової літератури з теми "Collisional parameters"

Автор: Grafiati

Опубліковано: 25 травня 2024

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Статті в журналах з теми "Collisional parameters"

Chatterjee, A., and A. Ruina. "A New Algebraic Rigid-Body Collision Law Based on Impulse Space Considerations." Journal of Applied Mechanics 65, no. 4 (December 1, 1998): 939–51. http://dx.doi.org/10.1115/1.2791938.

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We present a geometric representation of the set of three-dimensional rigid-body collisional impulses that are reasonably permissible by the combination of non-negative post-collision separation rate, non-negative collisional compression impulse, non-negative energy dissipation and the Coulomb friction inequality. The construction is presented for a variety of special collisional situations involving special symmetry or extremes in the mass distribution, the friction coefficient, or the initial conditions. We review a variety of known friction laws and show how they do and do not fit in the permissible region in impulse space as well as comment on other attributes of these laws. We present a few parameterizations of the full permissible region of impulse space. We present a simple generalization to arbitrary three-dimensional point contact collisions of a simple law previously only applicable to objects with contact-inertia eigenvectors aligned with the surface normal and initial relative tangential velocity component (e.g., spheres and disks). This new algebraic collision law has two restitution parameters for general three-dimensional frictional single-point rigid-body collisions. The new law generates a collisional impulse that is a weighted sum of the impulses from a frictionless but nonrebounding collision and from a perfectly sticking, nonrebounding collision. We describe useful properties of our law; show geometrically the set of impulses it can predict for several collisional situations; and compare it with existing laws. For simultaneous collisions we propose that the new algebraic law be used by recursively breaking these collisions into a sequence ordered by the normal approach velocities of potential contact pairs.

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Arakawa, Sota, Hidekazu Tanaka, and Eiichiro Kokubo. "Impacts of Viscous Dissipation on Collisional Growth and Fragmentation of Dust Aggregates." Astrophysical Journal 933, no. 2 (July 1, 2022): 144. http://dx.doi.org/10.3847/1538-4357/ac7460.

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Abstract Understanding the collisional behavior of dust aggregates consisting of submicron-sized grains is essential to unveiling how planetesimals formed in protoplanetary disks. It is known that the collisional behavior of individual dust particles strongly depends on the strength of viscous dissipation force; however, impacts of viscous dissipation on the collisional behavior of dust aggregates have not been studied in detail, especially for the cases of oblique collisions. Here we investigated the impacts of viscous dissipation on the collisional behavior of dust aggregates. We performed numerical simulations of collisions between two equal-mass dust aggregates with various collision velocities and impact parameters. We also changed the strength of viscous dissipation force systematically. We found that the threshold collision velocity for the fragmentation of dust aggregates barely depends on the strength of viscous dissipation force when we consider oblique collisions. In contrast, the size distribution of fragments changes significantly when the viscous dissipation force is considered. We obtained the empirical fitting formulae for the size distribution of fragments for the case of strong dissipation, which would be useful to study the evolution of size and spatial distributions of dust aggregates in protoplanetary disks.

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Arakawa, Sota, Hidekazu Tanaka, and Eiichiro Kokubo. "Collisional Growth Efficiency of Dust Aggregates and Its Independence of the Strength of Interparticle Rolling Friction." Astrophysical Journal 939, no. 2 (November 1, 2022): 100. http://dx.doi.org/10.3847/1538-4357/ac96e1.

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Abstract The pairwise collisional growth of dust aggregates consisting of submicron-sized grains is the first step of planet formation, and understanding the collisional behavior of dust aggregates is therefore essential. It is known that the main energy dissipation mechanisms are the tangential frictions between particles in contact, namely, rolling, sliding, and twisting. However, there is great uncertainty for the strength of rolling friction, and the dependence of the collisional growth condition on the strength of rolling friction was poorly understood. Here we performed numerical simulations of collisions between two equal-mass porous aggregates with various collision velocities and impact parameters, and we also changed the strength of rolling friction systematically. We found that the threshold of the collision velocity for the fragmentation of dust aggregates is nearly independent of the strength of rolling friction. This is because the total amount of the energy dissipation by the tangential frictions is nearly constant even though the strength of rolling friction is varied.

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Seaton, M. J. "New Atomic Data for Astronomy: An Introductory Review." Highlights of Astronomy 10 (1995): 570–71. http://dx.doi.org/10.1017/s1539299600012065.

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Astronomers require the following basic atomic data: energy levels and wavelengths’, radiative transition probabilities; cross sections for photo-ionisation and for collisional processes; and line profile parameters. They also require processed data such as: level populations; opacities; radiation forces; line emissivities; and collisional rate-coefficients.Many of the data used by astronomers come from theoretical work. Experimental work is of importance in determining accurate wavelengths, in providing essential checks on theory for radiative probabilities and collision rates, and in the determination of line-profile parameters. Experimental studies are particularly important for processes of collisional ionisation.

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Jesus, Antônio D. C., Rafael S. Ribeiro, Alessandro Rossi, and Ernesto Veira Neto. "Evasive Maneuvers in Space Debris Environment and Technological Parameters." Mathematical Problems in Engineering 2012 (2012): 1–15. http://dx.doi.org/10.1155/2012/126521.

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We present a study of collisional dynamics between space debris and an operational vehicle in LEO. We adopted an approach based on the relative dynamics between the objects on a collisional course and with a short warning time and established a semianalytical solution for the final trajectories of these objects. Our results show that there are angular ranges in 3D, in addition to the initial conditions, that favor the collisions. These results allowed the investigation of a range of technological parameters for the spacecraft (e.g., fuel reserve) that allow a safe evasive maneuver (e.g., time available for the maneuver). The numerical model was tested for different values of the impact velocity and relative distance between the approaching objects.

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Ngo, N. H., H. Tran, R. R. Gamache, and J. M. Hartmann. "Pressure effects on water vapour lines: beyond the Voigt profile." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 370, no. 1968 (June 13, 2012): 2495–508. http://dx.doi.org/10.1098/rsta.2011.0272.

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A short overview of recent results on the effects of pressure (collisions) regarding the shape of isolated infrared lines of water vapour is presented. The first part of this study considers the basic collisional quantities, which are the pressure-broadening and -shifting coefficients, central parameters of the Lorentzian (and Voigt) profile and thus of any sophisticated line-shape model. Through comparisons of measured values with semi-classical calculations, the influences of the molecular states (both rotational and vibrational) involved and of the temperature are analysed. This shows the relatively unusual behaviour of H 2 O broadening, with evidence of a significant vibrational dependence and the fact that the broadening coefficient (in cm −1 atm −1 ) of some lines increases with temperature. In the second part of this study, line shapes beyond the Voigt model are considered, thus now taking ‘velocity effects’ into account. These include both the influence of collisionally induced velocity changes that lead to the so-called Dicke narrowing and the influence of the dependence of collisional parameters on the speed of the radiating molecule. Experimental evidence of deviations from the Voigt shape is presented and analysed. The interest of classical molecular dynamics simulations, to model velocity changes, together with semi-classical calculations of the speed-dependent collisional parameters for line-shape predictions from ‘first principles’, are discussed.

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Chernoff, David F., and Xiaolan Huang. "Frequency of Stellar Collisions in Three-Body Heating." Symposium - International Astronomical Union 174 (1996): 263–72. http://dx.doi.org/10.1017/s0074180900001601.

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The probability for collisional interaction of three body binaries is calculated as a function of the physical radius and mass of the stellar objects and the depth of the cluster potential well. For typical cluster parameters, there is a significant chance of physical collision for objects as small as white dwarfs. One consequence of the collisions is to lower the amount of heat produced from hardening a binary, thereby diminishing the efficiency of the three-body heating mechanism.

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Campo Bagatin, A., and P. Farinella. "Collisional reaccumulation of asteroids." International Astronomical Union Colloquium 173 (1999): 145–52. http://dx.doi.org/10.1017/s0252921100031341.

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AbstractWe have developed a new version of the code developed by Campo Bagatin (1994a, b) to model the collisional evolution of the asteroid size distribution. The new code distinguishes between “intact”, unfractured asteroids and asteroids converted by energetic collisions into “piles of rubble”. We have run a number of simulations of the collisional evolution process to assess the size range where reaccumulated bodies should be expected to be abundant in the main asteroid belt. We find that this diameter range ranges from about 10 to 100 km, but may extend to smaller or larger bodies depending on the prevailing collisional response parameters.

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FIORE, M., F. FIÚZA, M. MARTI, R. A. FONSECA, and L. O. SILVA. "Relativistic effects on the collisionless–collisional transition of the filamentation instability in fast ignition." Journal of Plasma Physics 76, no. 6 (August 20, 2010): 813–32. http://dx.doi.org/10.1017/s0022377810000413.

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AbstractRelativistic collisional effects on the filamentation instability are analytically and numerically investigated by comparing collisionless and collisional scenarios for a fast ignition (FI) configuration. The theoretical kinetic model, including warm species and space charge effects, predicts the preferential formation of larger filaments and the inhibition/enhancement of the instability when collisions are accounted for. These collisional effects are qualitatively and quantitatively confirmed by 1D and 2D particle-in-cell (PIC) simulations, also providing a physical picture for the inhibition/enhancement regime due to collisions, based on the electron beam slowdown. By plugging typical FI parameters in the dispersion relation, the theoretical model predicts significant growth rates of the instability deep inside the FI target, thus showing the potential role of the filamentation instability as a mechanism for energy deposition into the pellet core.

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Mohammed, A. I., and C. S. Adams. "Ion shock layer formation during multi-ion-species plasma jet stagnation events." Physics of Plasmas 29, no. 7 (July 2022): 072307. http://dx.doi.org/10.1063/5.0087509.

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We report the characteristics of collisional plasma shocks formed during interactions between low density ([Formula: see text] cm−3), low temperature ([Formula: see text] eV), high velocity (30 km s−1), plasma jets and stagnant plasma of similar parameters. This investigation seeks to probe the structure of shocks in multi-ion-species plasmas, in particular, the presence of gradient-driven ion species separation at the shock front. The railgun-accelerated jets utilized here have previously been shown to exist in a collisional regime with intra-jet collisional mean-free-path substantially smaller than jet size [Schneider et al., Plasma Sources Sci. Technol. 29, 045013 (2020)]. To induce collisions, a dielectric barrier is located downstream of the railgun to stagnate an initially supersonic plasma jet. Around the time of stagnation, the railgun emits a second jet which shortly collides with the stagnant plasma. The presence of a structure emitting in the UV-visible band is evident in high-speed photographs of the moments immediately following the arrival of the second jet at the stagnant plasma. Analysis of interferometric and spectroscopic data suggests that the observed increase in density from the jet to the post-collision plasma is consistent with the formation of a bow shock structure with a multi-millimeter-scale ion shock layer.

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Дисертації з теми "Collisional parameters"

Mishina, Tatiana. "Pressure-induced collisional parameters of rovibrational lines of water vapour and ozone." Besançon, 2010. http://www.theses.fr/2010BESA2036.

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The information about rotation-vibration spectral lines of water vapour and ozone is necessary for atmospheric studies, modeling of radiation transfer, climate changes, ozone layer depletion and green house effect. The goals of the present work are focused on improvements and testing some existing semi-classical and semi empirical methods for colisional line width and shift calculation, as wel as on studies of the influence of interference of water spectral lines on the atmospheric absorption coefficient. The main new result obtained are the following ; I, using the generalized Euler transformation for the summation of divergent series allowed obtaining a convergent expression of the interruption (or “efficency”) function and calculation of new resonance functions in the cases of strong (HF-HF) and weak (CO-CO) dipole-dipole and dipole quadrupole (HF-N2)interactions; II nitrogen and oxygen-broadening coefficients of ozone lines were calculated by semi-classical RBE and semi-empirical methods for the v1+v3 band; III, vibrational dependence of classical trajectories was studied for the 1 th order contribution to the rovibrational shifts of O3-N2 lines in the framework of semi classical RB approach with exact trajectories and vibrational dependence of isotropic potential coming from O3 dipole moment and polarizability; IV, values of effective dipole polarizability in excited vibrational state were obtained for all vibrational bands of water vap our experimentally studied in the litterature; V, colisional parameters of water vapour spectral lines were calculated for highly excited ro-vibrational states up to the dissociation limit of 25 000 Cm-1; VI, interference of slanting atmospheric paths for winter conditions of mid-latitude atmosphere model and to the disappearance of micro window region for increasing zenithal angle
Les informations sur les raies de rotation-vibration de la vapeur d'eau et de l'ozone sont nécessaires pour les études atmosphériques ainsi que pour la modélisation du transfert radiatif, des changements du climat, la diminution de la couche d'ozone et de l'effet de serre. Les objectifs de ce travail sont focalisés sue des améliorations et des tests de certaines méthodes semi-classiques et semi-empiriques existantes pour calculer les largeurs et les déplacements collisionnels de raies spectrales ainsi que sur études de l'influence de l'interface de raies spectrales de la vapeur d'eau sur le coefficient d'absorption dans l'atmosphère. Les principaux résultats obtenus sont les suivants : I , l'utilisation de la transformation généralisée d'Euler pour la sommation de séries divergentes a permis d'obtenir une expression convergente pour la fonction d'interruption et calculer les nouvelles fonctions de résonance dans le cas des interactions dipôle-dipôle forte (HF-HF) et faible (CO-CO) et interaction dipôle-quadrupole (HF-N2) ;II, des coefficients d'élargissement de raies d'ozone par l'azote et l’oxygéné ont été calculés par la méthode semi classique RB avec trajectoires exactes (RBE) et par la méthode semi-empirique pour la bande v1+v3 ; III, la dépendance vibrationnelle des trajectoires classiques a été étudiée pour la contribution du 1er ordre dans le déplacement de raies O3-N2 rovibrationnelles dans le cadre de la méthode semi-classique RBE aisi que la dépendance vibrationnelle du potentiel isotope venant du moment dipolaire et de la polarisabilité de O3 ; IV, les valeurs de la polarisabilité dipolaire effective dans les états vibrationnels excités ont été obtenues pour toutes les bandes vibrationnelles de la vapeur d'eau étudiées expérimentalement dans la littérature ; V, les paramètres collisionnels de raies spectrales de la vapeur d'eau ont été calculés pour les états rovibrationnels très fortement excités, jusqu'à la limite de dissociation 25 000 Cm-1 ; VI, il est démontré que l'interface de raies spectrales de la vapeur d'eau conduit à une erreur notable dans le calcul du coefficient d'absorption atmosphérique pour des trajets inclinés dans les conditions d'hiver du modèle « mid-latitude » de l'atmosphère ainsi qu'à la disparition de la région de la micro-fenête pour les grandes valeurs de l'angle du zénith

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Khalid, Muhammad. "Influence of solvent viscosity, polarity and polarizability on the chemiluminescence parameters of inter and intramolecular electron transfer initiated chemiexcitation systems." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/46/46136/tde-29092015-114251/.

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The cyclic peroxides: diphenoyl peroxide (1), spiro-adamantyl-1,2-dioxetanone (2) and 4-(3-tert-butyldimethylsilyloxyphenyl)-4-methoxyspiro[1.2-dioxetane-3.2\'-adamantane] (3) synthesized, purified and characterized, also their kinetic and chemiluminescence (CL) properties were determined. The influence of solvent polarity on the chemiexcitation parameters of the catalyzed decomposition of 1 and 2, as well as the induced decomposition of 3 were examined in several binary solvent mixtures with different polarity and polarizability parameters, but similar viscosities. For solvents with low polarity, singlet quantum yields for the intermolecular catalyzed decomposition of diphenoyl peroxide (1,) and 1,2-dioxetanone (2) increase in function of medium polarity, showing maximum values in mediums of intermediate polarity, and decreasing in highly polar mixtures. For the induced decomposition of 3, the quantum yield showed to increase with increasing solvent polarity, including high polar solvent systems. In the binary solvent systems studied, the polarizability parameter showed to be contrary to the polarity values, therefore, it might appear that an increase of polarizability leads to a decrease in the singlet quantum yields for catalyzed decomposition of diphenoyl peroxide (1) and the induced decomposition of 3, however an increase in the singlet quantum yields for 1,2-dioxetanone 2. The three CL systems were also studied in binary solvent mixtures with different viscosities but similar polarity and polarizability parameters and singlet quantum yields showed an increase with increasing medium viscosity. Data were analyzed by using the collisional and the free volume models. The highly efficient intramolecular system induced 1,2-dioxetane 3 decomposition showed to be much more sensible to viscosity effects than the inefficient intermolecular systems. This surprising fact indicates that, even showing a significant solvent-cage effect, the induced 1,2-dioxetane should occur by an intramolecular electron back transfer. Moreover, chemiluminescence parameters of these systems were studied in several pure solvents. The obtained singlet quantum yields were correlated with viscosity, polarizability and polarity parameters by using multiple linear regression analysis.
Os peróxidos cíclicos: peróxido de difenoila (1), spiro-adamantil-1,2-dioxetanona (2) e 4-(3-terc-butildimetilsililoxifenil)-4-metoxispiro[1,2-dioxetano-3.2\'-adamantano] (3) foram sintetizados, purificados e caracterizados e as suas propriedades cinéticas e de quimiluminescência (CL) determinadas. A influência da polaridade do solvente sobre os parâmetros de quimi-excitação da decomposição catalisada de 1 e 2, e a decomposição induzida de 3 foi examinada em diversas misturas binárias de solventes com parâmetros de polaridade e polarizabilidade diferente, mas viscosidades semelhantes. Para solventes com baixa polaridade, os rendimentos quânticos singlete para a decomposição catalisada intermolecular do peróxido de difenoila (1) e 1,2-dioxetanona (2) aumentam em função da polaridade do meio, mostrando valores máximos em meios com polaridade intermediária, e diminuim para misturas altamente polares. Para a decomposição induzida de 3, o rendimento quântico mostrou aumentar com o aumento da polaridade do solvente, inclusive para sistemas com alta polaridade. Nos sistemas binários de solventes estudados, os parâmetros de polarizabilidade mostraram-se contrários aos valores de polaridade, portanto, parece que um aumento da polarizability leva a uma diminuição nos rendimentos quânticos singlete para a decomposição catalisada do peróxido de difenoila (1) e a decomposição induzida de 3, no entanto, um aumento nos rendimentos quânticos singlete para a 1,2-dioxetanona 2. Os três sistemas de CL também foram estudados em misturas binárias de solventes com diferentes viscosidades, mas com parâmetros de polaridade e polarizabilidade semelhantes e os rendimentos quânticos singlete mostraram aumentar com o aumento da viscosidade do meio. Os dados foram analisados usando tanto o modelos colisional quando o modelo de volume livre. Surpreendentemente, o sistema altamente eficiente decomposição induzida intramolecular do 1,2-dioxetano 3 mostrou-se muito mais sensível aos efeitos da viscosidade do que os sistemas intermoleculares ineficientes, o que indica claramente que a decomposição induzida do 1,2-dioxetano deve ocorrer por um processo de retro-transferência de elétron intramolecular. Além disso, os parâmetros de quimiluminescência destes sistemas foram estudados em vários solventes puros. Os rendimentos quânticos singlete obtidos foram correlacionados com parâmetros de viscosidade, polarizabilidade e polaridade usando análise de regressão linear múltipla.

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Troitsyna, Larisa. "Approche semi-classique aux paramètres collisionnels de raies spectrales de CH3I pour applications atmosphériques et planétologiques." Electronic Thesis or Diss., Bourgogne Franche-Comté, 2021. http://www.theses.fr/2021UBFCD061.

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La molécule d'iodure de méthyle CH3I est devenue récemment l'objet d'études spectroscopiques intenses en raison de son rôle dans la diminution de la couche d'ozone et de son danger pour la santé humaine au cas d'une émission accidentelle dans l’atmosphère. La bande fondamentale nu6 apparaît particulièrement adaptée à la détection atmosphérique de CH3I, car elle tombe dans la fenêtre de transparence à 11mu m. Cependant, les paramètres spectroscopiques actuellement disponibles pour CH3I perturbé par les principales espèces atmosphériques sont limités à quelques mesures extrêmement rares à température ambiante et manquent dans les bases de données spectroscopiques. Pour compléter / remplacer les données expérimentales manquantes, dans le cadre du Projet de Recherche International franco-russe SAMIA, les coefficients d'élargissement de raies pour les paires atmosphériques clés CH3I-CH3I, CH3I-N2, CH3I-O2, CH3I-air sont calculés de manière semi classique, avec l'utilisation du formalisme de Robert-Bonamy amélioré par des trajectoires exactes, dans de larges gammes de nombres quantiques rotationnels typiquement demandés par les bases de données (0 < J < 70, K < 20) et pour les six sous-branches RP, PP, RQ PQ, RR, PR de la bande nu6 ; leur dépendance vibrationnelle ainsi que les dépendances de sous-branche et en température (avec la loi exponentielle traditionnelle et la nouvelle loi "double-power" ) sont également abordées. Des arguments sont donnés pour justifier ce choix de la méthode facilement praticable face à ses modifications avancées mais moins en accord avec les mesures. Des comparaisons sont faites avec les mesures disponibles et des résultats semi empiriques alternatifs, indiquant l'importance du modèle de potentiel d'interaction, en particulier de sa partie isotrope pilotant les trajectoires, pour une description réaliste des largeurs de raies collisionnelles
Methyl iodide molecule CH3I has come recently into focus of intense spectroscopic studies due to its role in the ozone layer depletion and its danger for human health in case of an accidental release in the atmosphere. For its atmospheric detection particularly suitable is the nu6 fundamental, which falls into the transparency window at 11 mu m. However, currently available spectroscopic line-shape parameters for CH3I perturbed by main atmospheric species are limited to some extremely scarce measurements at ambient temperature and are missing in spectroscopic databases. To supplement/replace the missing experimental data, in the frame of the French-Russian International Research Project SAMIA, room-temperature (296 K) line-broadening coefficients for the key atmospheric pairs CH3I-CH3I, CH3I-N2, CH3I-O2,CH3I-air are calculated semi-classically, with the use of the Robert-Bonamy formalism improved by exact trajectories, in wide ranges of rotational quantum numbers typically requested by databases (0 < J < 70, K < 20) and for all six sub-branches RP, PP, RQ PQ, RR, PR of the nu6 band; their vibrational dependence as well as sub-branch dependence and temperature dependence (with the traditional power and recently suggested double-power laws) are also addressed. Arguments are given to support this choice of the easily practicable method contrary to its advanced but less agreeing with measurements modifications. Comparisons are made with available measurements and alternative semi-empirical results, indicating the importance of the interaction potential model, in particular of its isotropic part governing the trajectories, for a realistic description of collisional line-widths

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Hwang, Lorraine J. "Teleseismically determined source parameters of several large collision-zone earthquakes /." Diss., Pasadena, Calif. : California Institute of Technology, 1991. http://resolver.caltech.edu/CaltechETD:etd-06292005-161026.

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Shore, Patrick. "Swinging Babe's Bat: Optimizing Home Run Distance Using Ideal Parameters." Scholarship @ Claremont, 2019. https://scholarship.claremont.edu/cmc_theses/2226.

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Significant research has been conducted on the physics of ball and bat collisions in an effort to model and understand real-world conditions. This thesis expands upon previous research to determine the maximum distance a ball can travel under ideal circumstances. Bat mass, bat speed, pitch speed and pitch spin were controlled values. These values were selected based on the highest recorded MLB values for their respective category. Specifically these are: Babe Ruth’s largest bat, Giancarlo Stanton’s recorded swing speed and Aroldis Chapman’s fastest fastball. A model was developed for a planar collision between a bat and ball using conservation laws in order to achieve the maximum exit velocity of the ball during a head-on collision. However, this thesis is focused on home runs and long fly-balls that occur from oblique collisions rather than the line drives produced by head-on collisions. The planar collision model results were adjusted to oblique collisions based on data from previous experimental research. The ball and bat were assumed to be moving in opposite directions parallel to one another at the point of impact with the ball slightly elevated above the bat. The post-collision results for the launch angle, spin and final exit velocity of the ball were calculated as functions of the perpendicular distance from the centerline of the bat to the centerline of the ball. Trajectories of the ball were calculated using a flight model that measured the final distance of the ball based on lift and drag forces. The results indicate that the optimum pre-collision parameters described above will maximize the distance traveled by the ball well beyond the farthest recorded home run distance. Experimentally determined factors such as the drag coefficient and coefficient of restitution have a significant impact on the flight of the ball. Implications of the results are discussed.

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Abdurakhmanov, Ilkhom. "Impact-parameter convergent close-coupling approach to antiproton-atom collisions." Thesis, Curtin University, 2011. http://hdl.handle.net/20.500.11937/1721.

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This thesis is devoted to extension of the convergent close-coupling (CCC) method to heavy projectiles and its application to the theoretical studies of antiproton scattering on the hydrogen and helium targets.In the Introduction (Chapter 1) the motivation for the study and the current status of antiproton scattering on hydrogen and helium are presented. Other theoretical methods that previously have been applied to these problems are reviewed and their limitations are indicated. The extension of the fully quantummechanical CCC method to ion-atom collisions is presented in Chapter 2. The derivations of the momentum-space coupled-channel Lippmann-Schwinger integral equations from the exact Schr¨odinger equation is given in detail. Transition matrix elements are derived in momentum-space. In Chapter 3 a direct method for solving multi-dimensional Lippmann-Schwinger integral equations without recourse to partial-wave expansion or any other transformation scheme will be described. A direct method has been applied to the antiproton-hydrogen as well as to the proton-hydrogen collisions. In Chapter 4 we solve the full multichannel problem by transforming the coupled-channel integral equations into the impactparameter representation. The scattering amplitude necessary to calculate the differential and total cross sections will be derived from the transition matrix elements. The results of the CCC calculations for antiproton scattering from atomic hydrogen and helium are presented and compared with available experimental data and the results of other calculations in Chapter 5 and Chapter 6, respectively. Finally, in Chapter 7, we draw conclusions arising from this work and indicate future directions for the research.Main results of this work • The convergent close-coupling method has been extended to heavy projectiles and applied to antiproton scattering on atomic hydrogen and helium. • For the first time, the relative motion of the heavy particles in antiproton collisions with atomic hydrogen and helium has been treated quantummechanically. • A direct method to solving the three-dimensional momentum-space coupledchannel Lippmann-Schwinger integral equations has been developed. • A scheme for transforming the three-dimensional Lippmann-Schwinger integral equations into the impact-parameter representation has been developed. The fully off-shell transition matrix elements in the impactparameter space have been derived. • For the first time, the fully quantum mechanical calculations of the cross sections for all the major channels of interest in antiproton collisions with hydrogen and helium have been performed over a wide range of scattering energies. • The total ionization cross sections for the H target has been calculated. The results are in excellent agreement with the available experiment. An overall agreement of the present results with the semiclassical calculations by other groups has practically confirmed the validity of the semiclassical approximation imposed on the relative heavy particle motion. • The total cross section for the He single ionization has been calculated using frozen-core (FC) and multi-configuration (MC) approximation for the target. As opposed to rather sophisticated and rigorous MC calculations the FC results agree with the experimental data at a wider energy range. • For the first time, based on the fully quantum-mechanical treatment of the problem the triple differential cross sections have been calculated for antiproton scattering on both H and He.• The p−H results for the various differential ionization cross sections agree reasonably well with the results of the semiclassical close-coupling and the continuum-distorted-wave-eikonal-initial-state (CDW-EIS) approaches, particularly at high energies. • The longitudinal ejected electron and recoil-ion momentum distributions for the single ionization of helium have been calculated. The results are in good agreement with the available experimental data.

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Martin, Matthew S. "Preliminary studies concerning [Delta gamma]Bs measurements in proton antiproton collisions at [root of]s = 2.0 TeV." Thesis, University of Oxford, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275261.

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Movahedi-Lankarani, Hamid. "Canonical equations of motion and estimation of parameters in the analysis of impact problems." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184490.

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The transient dynamic analysis of constrained mechanical systems may require the solution of a mixed set of algebraic and differential equations of motion. The usual formulation of these equations is expressed in terms of the accelerations of the system components. A canonical form of the equations of motion in terms of the system velocities and the time derivative of the system momenta may be used instead. This is a natural form of the equations in which all the state variables are explicitly expressed, and have the same physical importance. The numerical solution obtained from the canonical equations shows more accuracy and stability, specifically for systems with large and fluctuating forces. For the mechanical systems that undergo an impact, the usual numerical solution of the equations of motion is not valid. Two different methods of analysis of impact problems are presented. In one method, the variations of the impulsive force during the contact period are directly added to the vector of forces in the canonical equations of motion. In the second method, based on the assumption of instantaneous nature of impact, a set of momentum balance-impulse equations is derived by explicitly integrating the canonical equations. These equations are solved at the time of impact for the jump in the system momenta right after impact. Necessary parameters are evaluated for the performance of the two methods of analysis. These parameters include the maximum relative indentation, the maximum contact force, and the coefficient of restitution. The parameters are determined for the collision between two bodies in a system with any general geometric or material properties. The influence of friction modeling in the magnitude and the direction of the total force at the contact surfaces is discussed. The dynamics of a vehicle collision is studied in order to illustrate the efficiency of obtaining a solution to the canonical equations, the simplicity of solving the momentum balance-impulse equations.

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Wheaton, Spencer Miles. "The centrality dependence of thermal parameters in Pb-Pb collisions at 158 GeV/nucleon." Master's thesis, University of Cape Town, 2001. http://hdl.handle.net/11427/6512.

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Includes bibliographical references.
A review of the Hardon Gas model and its application to Pb+Pb CERN SPS collision data at a beam energy of 158 GeV/nucleon. The centrality dependence of the freeze-out parameters, characterizing both the hadron multiplicities and the transverse momentum spectra, are determined. This privides valuable information on the effect of the system size on chemical-and thermal frees-out and contributions towards the systematic understandig of the experimental data.

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Varas, Jaime Armando. "Employment of neural networks in the estimation of impact parameters." Thesis, The University of Sydney, 2002. https://hdl.handle.net/2123/27885.

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In this study, we employed a two-stage backpropagation neural network (NNW) to estimate the impact parameter (b) of heavy-ion collisions. Using Monte-Carlo (MC) generated Pb-Pb events at 160 GeV/nucleon we employed three observables from each event to train the NNW. The generated events were target-projectile in nature, from which the charged pion multiplicity (MULT), largest spectator fragment (ZMAX) and charge flow in the forward direction (sz) were used as input signals for the NNW. A statistical approach that employed the weighted mean of the three inputs to estimate b was used as a test method, against which the NNW's results were compared. The results showed, that the NNW was as accurate as the weighted mean in estimating b. Using central events fom EMUOl data comprising of Au-Au events at 11 GeV/nucleon and Pb-Pb events at 158 GeV/nucleon, we extracted the observables MULT, ZMAX and Qm from each event, and utilising the trained NNW we estimated b. A comparison of MC generated events of a similar b range was made with our EMUOl results, and it was shown that the two data sets agreed within statistical errors. A further comparison of the pseudorapidity distribution between the two data sets revealed that the estimated b for the EMUOl data, was consistent with the MC data.

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Книги з теми "Collisional parameters"

Shaffer, Clifford A. A real-time robot arm collision detection system. [Blacksburg, Va.]: Dept. of Computer Science, Virginia Polytechnic Institute and State University, 1990.

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Shaffer, Clifford A. A real-time robot arm collision detection system. [Blacksburg, Va.]: Dept. of Computer Science, Virginia Polytechnic Institute and State University, 1990.

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M, Herb Gregory, Virginia Polytechnic Institute and State University. Dept. of Computer Science., and Goddard Space Flight Center, eds. A real-time robot arm collision detection system. [Blacksburg, Va.]: Dept. of Computer Science, Virginia Polytechnic Institute and State University, 1990.

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Cook, George E. Development of ROBOSIM for academic/industrial use: Final report. [Washington, DC: National Aeronautics and Space Administration, 1994.

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Cook, George E. Development of ROBOSIM for academic/industrial use: Final report. [Washington, DC: National Aeronautics and Space Administration, 1994.

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Tripathi, Ratikanta. Universal parameterization of absorption cross sections: Light systems. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1999.

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Tripathi, Ratikanta. Universal parameterization of absorption cross sections. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1997.

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Aum, Ho Sung. Parameters affecting mechanical collisions. 1992.

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Henriksen, Niels Engholm, and Flemming Yssing Hansen. Microscopic Interpretation of Arrhenius Parameters. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198805014.003.0008.

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This chapter reviews the microscopic interpretation of the pre-exponential factor and the activation energy in rate constant expressions of the Arrhenius form. The pre-exponential factor of apparent unimolecular reactions is, roughly, expected to be of the order of a vibrational frequency, whereas the pre-exponential factor of bimolecular reactions, roughly, is related to the number of collisions per unit time and per unit volume. The activation energy of an elementary reaction can be interpreted as the average energy of the molecules that react minus the average energy of the reactants. Specializing to conventional transition-state theory, the activation energy is related to the classical barrier height of the potential energy surface plus the difference in zero-point energies and average internal energies between the activated complex and the reactants. When quantum tunnelling is included in transition-state theory, the activation energy is reduced, compared to the interpretation given in conventional transition-state theory.

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High-multiplicity lead-lead interactions at 158 GeV/c per nucleon. [Washington, DC: National Aeronautics and Space Administration, 1996.

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Частини книг з теми "Collisional parameters"

Beyer, H.-J., K. Blum, and M. C. Standage. "Stokes Parameters ƞ1,2,3 and Scattering Parameters λ,χ for Positive and Negative Scattering Angles in Electron-Photon Coincidence Experiments." In Fundamental Processes in Atomic Collision Physics, 573–77. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4613-2125-5_22.

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Qian, Shenghua. "Vehicle Collision Prediction Model on the Internet of Vehicles." In Proceeding of 2021 International Conference on Wireless Communications, Networking and Applications, 518–30. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-2456-9_53.

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AbstractAn active collision prediction model on the Internet of Vehicles is proposed. Through big data calculation on the cloud computing platform, the model predicts whether the vehicles may collide and the time of the collision, so the server actively sends warning signals to the vehicles that may collide. Firstly, the vehicle collision prediction model preprocesses the data set, and then constructs a new feature set through feature engineering. For the imbalance of the data set, which affects predictive results, SMOTE algorithm is proposed to generate new samples. Then, the LightGBM algorithm optimized by Bayesian parameters is used to predict the vehicle collision state. Finally, for the problem of low accuracy in predicting the collision time, the time prediction is transformed into a classification problem, and the Bayesian optimization K-means algorithm is used to predict the vehicle collision time. The experimental results prove that the vehicle collision prediction model proposed in this paper has better results.

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Rankin, Patricia. "Precision Measurement of Electroweak Parameters at the Stanford Linear Collider." In Radiative Corrections for e+e- Collisions, 257–72. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-74925-4_16.

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Riemann, T., D. Bardin, M. Bilenky, and M. Sachwitz. "On the derivation of Standard Model Parameters from the Z Peak." In Radiative Corrections for e+e- Collisions, 162–78. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-74925-4_10.

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Passarino, Giampiero. "Radiative Corrections in the Standard Model And the Rho Parameter." In Radiative Corrections for e+e- Collisions, 179–90. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-74925-4_11.

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Clark, J. D., B. W. Wright, J. D. Wrbanek, and A. Garscadden. "Electron Collision Cross Sections and Transport Parameters in CHF3." In Gaseous Dielectrics VIII, 23–29. Boston, MA: Springer US, 1998. http://dx.doi.org/10.1007/978-1-4615-4899-7_3.

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Ségur, Pierre, M. C. Bordage, and M. Yousfi. "A comparative Study of the Computing Methods Actually in use for Accurate Determination of Swarm Parameters." In Swarm Studies and Inelastic Electron-Molecule Collisions, 3–22. New York, NY: Springer New York, 1987. http://dx.doi.org/10.1007/978-1-4612-4662-6_1.

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Daughton, William, and Vadim Roytershteyn. "Emerging Parameter Space Map of Magnetic Reconnection in Collisional and Kinetic Regimes." In Space Sciences Series of ISSI, 271–82. New York, NY: Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4614-6461-7_18.

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Tan, Zhirong, Gang Xing, Xing Gao, and Xin Cui. "Turbulent Flow Simulation of Bridge Piers and Navigation Safety of Ships in Curved River Sections with Variable Water Level." In Lecture Notes in Civil Engineering, 736–48. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-19-6138-0_64.

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AbstractSome of the bridges across the Yangtze River in the Three Gorges Reservoir area are in the curved section, and the collision prevention of bridges is a hot issue in the current industry. The system of ships sailing across bridges is a complex system in the discipline of transportation engineering. It is affected by ship conditions, channel conditions, meteorology and hydrology, navigation management and human factors. In order to grasp the influence of turbulent flow near the piers of bridges in curved river sections and oblique flow during variable water level periods on ships crossing bridges, it is necessary to carry out numerical simulation analysis. Methods: By establishing a simple physical model of the water area of the bridge pier, the turbulent flow field of the bridge pier was simulated in two dimensions by Fluent software. Then the turbulent flow characteristics of the single pier and the tandem double pier were compared, and the flow velocity on the upstream side of the bridge pier was used as a parameter to carry out numerical simulation. Finally, the flow-induced drift of the ship is quantitatively calculated in combination with the flow velocity. Conclusion: The two-dimensional simulation confirms that the turbulent width of the bridge pier increases with the increase of the flow velocity. The turbulent width of the tandem double pier is larger than that of the single pier, but the vorticity extending downstream is smaller than that of the single pier. The deflection moment and flow-induced drift of the ship crossing the bridge confirm the risk of ship collision. It is necessary to add a multi-function navigation mark to collect water flow parameters in time, and introduce LED visual navigation in the bridge area to improve the reliability of ship navigation in the bridge area of the curved river section.

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de Deus, J. Dias, and Yu M. Shabelskit. "An Estimate of the Percolation Parameter in Heavy Ion Collisions." In Nuclear Dynamics: From Quarks to Nuclei, 119–22. Vienna: Springer Vienna, 2003. http://dx.doi.org/10.1007/978-3-7091-6014-5_12.

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Тези доповідей конференцій з теми "Collisional parameters"

Zhao, Yunhua, Bing Lu, Zhichao Yang, and Yingjie Zhong. "Discrete particle modeling of gas fluidization with random collisional parameters." In 7TH INTERNATIONAL SYMPOSIUM ON MULTIPHASE FLOW, HEAT MASS TRANSFER AND ENERGY CONVERSION. AIP, 2013. http://dx.doi.org/10.1063/1.4816913.

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Lopresti, S. "Overview of spacecraft fragmentation testing." In Aeronautics and Astronautics. Materials Research Forum LLC, 2023. http://dx.doi.org/10.21741/9781644902813-112.

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Abstract. Spacecraft fragmentation due to collisions with space debris is a major concern for space agencies and commercial entities, since the production of collisional fragments is one of the major sources of space debris. It is in fact believed that, in certain circumstances, the increase of fragmentation events could trigger collisional cascade that makes the future debris environmental not sustainable. Experimental studies have shown that the fragmentation process is highly complex and influenced by various factors, such as the material properties, the velocity and angle of the debris impact and the point of collision (e.g. central, glancing, on spacecraft appendages). In recent years, numerous impact tests have been performed, varying one or more of these parameters to better understand the physics behind these phenomena. In this context some tests have been also performed at the hypervelocity impact facility of the university of Padova. This paper provides an overview of the main experiments performed, the most critical issues observed and proposes some future directions for further research. Moreover, it summarizes the current state of research in spacecraft fragmentation, including the methods and techniques used to simulate debris impacts, the characterization of fragment properties and the analysis of the resulting debris cloud.

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Nishiyama, Akiko, Grzegorz Kowzan, Dominik Charczun, Roman Ciuryło, and Piotr Masłowski. "Application of mid-infrared frequency comb-based Fourier-transform spectroscopy to precise line-shape study of CO perturbed by N2." In Fourier Transform Spectroscopy. Washington, D.C.: Optica Publishing Group, 2023. http://dx.doi.org/10.1364/fts.2023.fth2a.3.

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We performed line-shape measurements of the fundamental vibrational band of CO perturbed by N2 with a mid-infrared frequency comb-based Fourier-transform spectrometer. We provide precise collisional line-shape parameters, which are of atmospheric science interest.

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Hurst, W. S., and G. J. Rosasco. "Q-branch spectral line shapes of D2 in foreign gases." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1985. http://dx.doi.org/10.1364/oam.1985.ft4.

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The collisional Dicke narrowing and broadening of spectral lines with foreign gas perturbers has been studied by measuring the third-order nonlinear susceptibility of isolated Q-branch (0-1) D2 lines. Perturber gas mass has been varied by employing dilute (5%) binary mixtures of D2 in H2, He, N2, or Ar, and densities at 296 K were varied from 0.25 to 5.7 amagat. We have used these data to test the validity of soft and hard collision models for describing the spectral line shape and the linewidth density dependence. At high densities, the data are well described by Lorentzian line shapes and a Dicke diffusion expression for the density dependence of the lindwidth. At lower densities, the line shape functions were fit to the data while fixing both the pressure broadening parameters to their high density values and the narrowing parameters to the values predicted from diffusion theory. For the light perturbing gases (H2, He), only the soft collision model fit the line shape and gave agreement with the observed linewidth. For the heavy perturber gases (N2, Ar), neither model described the line shape or the linewidth dependence, the disagreement being greater for Ar.

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Klische, W., and C. O. Weiss. "Instabilities and chaotic emission of far-infrared NH3 lasers." In Instabilities and Dynamics of Lasers and Nonlinear Optical Systems. Washington, D.C.: Optica Publishing Group, 1985. http://dx.doi.org/10.1364/idlnos.1985.wc3.

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We have investigated the dynamic behaviour of NH3-lasers. These have narrow homogeneous linewidths, high gain and the inhomogeneous broadening can be controlled (suppressed), and are therefore likely to display instabilities, even under homogeneous broadening conditions. The collisional and radiative processes leading to laser gain are well understood, all laser parameters are controllable.

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Wang, Y., and C. Shu. "Numerical Investigation on Head-On Collisions of Binary Micro-Droplets by an Improved Multiphase Lattice Boltzmann Flux Solver." In ASME 2016 5th International Conference on Micro/Nanoscale Heat and Mass Transfer. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/mnhmt2016-6533.

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Head-on collisions of binary micro-droplets are of great interest in both academic research and engineering applications. Numerical simulation of this problem is challenging due to complex interfacial changes and large density ratio between different fluids. In this work, the recently proposed lattice Boltzmann flux solver (LBFS) is applied to study this problem. The LBFS is a finite volume method for the direct update of macroscopic flow variables at cell centers. The fluxes of the LBFS are reconstructed at each cell interface through lattice moments of density distribution functions (DDFs). As compared with conventional multiphase lattice Boltzmann method, the LBFS can be easily applied to study complex multiphase flows with large density ratio. In addition, external forces can be implemented more conveniently and the tie-up between the time step and mesh spacing is also removed. Moreover, it can deal with complex boundary conditions directly as those do in the conventional Navier-Stokes solvers. At first, the reliability of the LBFS is validated by simulating a micro-droplet impacting on a dry surface at density ratio 832 (air to water). The obtained result agrees well with experimental measurement. After that, numerical simulations of head-on collisions of two micro droplets are carried out to examine different collisional behaviors in a wide range of Reynolds numbers and Weber numbers of 100 ≤ Re ≤ 2000 and 10 ≤ We ≤ 500. A phase diagram parameterized by these two control parameters is obtained to classify the outcomes of these collisions. It is shown that, at low Reynolds number (Re=100), two droplets will be coalescent into a bigger one for all considered Weber numbers. With the increase of the Reynolds number, separation of the collision into multiple droplets appears and the critical Weber number for separation is decreased. When the Reynolds number is sufficiently high, the critical Weber number for separation is between 20 and 25.

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Herman, R. M. "Scalar collisional interference parameters for the HD R[sub 1](0) and R[sub 1](1) lines in mixtures with He." In The 15th international conference on spectral line shapes. AIP, 2001. http://dx.doi.org/10.1063/1.1370668.

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Stankiewicz, Kamil, Franck Thibault, Piotr Wcislo, Maciej Gancewski, Nikodem Stolarczyk, and Hubert Jóźwiak. "INVESTIGATION OF COLLISIONAL EFFECTS IN MOLECULAR SPECTRA - COMPREHENSIVE DATASET OF LINE-SHAPE PARAMETERS FROM AB INITIO CALCULATIONS FOR He-PERTURBED HD." In 2022 International Symposium on Molecular Spectroscopy. Urbana, Illinois: University of Illinois at Urbana-Champaign, 2022. http://dx.doi.org/10.15278/isms.2022.fb09.

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Olberding, Joseph, Karla Petroskey, and Tara Leipold. "Coefficient of Restitution and Collision Pulse Duration in Low-Speed Vehicle-to-Barrier Impacts." In WCX SAE World Congress Experience. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2023. http://dx.doi.org/10.4271/2023-01-0624.

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<div class="section abstract"><div class="htmlview paragraph">The coefficient of restitution is utilized in various methods for determining the change in velocity (delta-V) associated with a vehicle collision event. Additionally, for a given delta-V, the magnitude of vehicle acceleration varies with different collision pulse durations. Collision restitution and duration parameters are thus considered by both accident reconstructionists and biomechanists in the investigation of vehicle collision severity and occupant injury potential. Because of the uniqueness of individual vehicle designs, it is difficult to determine a collision’s specific coefficient of restitution and crash pulse duration. Accident reconstructionists often estimate the values of these parameters based on staged crash tests. Prior studies involving low-speed collisions have sought to determine correlations between restitution and collision characteristics and have established equations to assist in estimating restitution. Most of these equations are based around the correlation between restitution and vehicle closing speed. Furthermore, the previous work is largely based on pre-2000 model year vehicles. This study seeks to expand the restitution data for vehicle-to-barrier collisions to a more modern vehicle fleet and examine potential vehicle and collision characteristics that influence restitution and crash pulse duration. The Insurance Institute for Highway Safety (IIHS) conducted a series of low-speed vehicle-to-barrier and vehicle-to-vehicle crash tests. The IIHS test series includes both front and rear collisions with a fixed bumper-like barrier in full-overlap and corner (offset) configurations. For this study, over 100 vehicle-to-barrier front and rear full-overlap collision videos were analyzed to compute the coefficient of restitution and crash pulse duration for each test. The relationships between vehicle weight, vehicle wheelbase, bumper engagement, and bumper construction with the coefficient of restitution and pulse duration were evaluated.</div></div>

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Brecha, R. J., Min Xiao, and H. J. Kimble. "Photon antibunching in optical bistability." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1988. http://dx.doi.org/10.1364/oam.1988.mm4.

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While the problem of photon antibunching in optical bistability has been the subject of numerous theoretical investigations, there appears to be no general result in the literature that includes a complete specification of the dependence of antibunching on the system parameters. Motivated by the importance of such a result to experimental observation of this effect, we present a treatment that includes the parametric dependences on cavity and atomic detunings, cooperativity parameter, nonradiative (collisional) damping, and the ratio of cavity and atomic damping rates. We also attempt to analyze the contribution of fourth-order correlations of the fluctuating fields, which have been neglected in previous treatments. Although the antibunching initially increases with decreasing system size due to the approximate scaling of quantum fluctuations as the inverse of the saturation photon number ns, higher-order fluctuations begin playing an increasingly important role at values of ns ⪝ 1. We show that the linearized theory itself does not necessarily break down for arbitrarily small values of ns (as previously suggested), but that photon antibunching is lost in this limit, thus placing restrictions on the design of an experiment.

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Звіти організацій з теми "Collisional parameters"

Heifets, S. A., G. A. Krafft, and M. Fripp. On asymmetric collisions with large disruption parameters. Office of Scientific and Technical Information (OSTI), June 1990. http://dx.doi.org/10.2172/6542621.

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Huijser, MP, J. W. Duffield, C. Neher, A. P. Clevenger, and T. Mcguire. Final Report 2022: Update and expansion of the WVC mitigation measures and their cost-benefit model. Nevada Department of Transportation, October 2022. http://dx.doi.org/10.15788/ndot2022.10.

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This report contains an update and an expansion of a cost-benefit model for wildlife-vehicle collisions and associated mitigation measures along highways, that was originally calculated in 2007 US$ and published in 2009. The direct cost values (vehicle repair, human injuries, human fatalities) were updated for deer, elk, and moose, and expanded by including additional species: gray wolf (Canis lupus), grizzly bear (Ursus arctos), and free ranging or feral domesticated species including cattle, horse, and burro. The costs associated with collisions were also expanded by including passive use, or nonuse values associated with the conservation value of selected wild animal species. The total costs (in 2020 US$) associated with a collision with deer, elk and moose were about 2-3 times (direct costs only) or about 3-4 times higher (direct costs and passive use values combined) compared to the values in 2007 US$. The passive use costs associated with threatened species (wolf, grizzly bear) were higher or much higher than the direct costs. The costs associated with mitigation measures (especially fences and wildlife crossing structures) were also updated and supplemented with new data. New cost-benefit analyses generated updated or entirely new threshold values for deer, elk, moose, and grizzly bear. If collisions with these large wild mammal species reach or surpass the threshold values, it is economically defensible to install the associated type and combination of mitigation measures, both based on direct use and passive use parameters and their associated values. The trend in increasing costs associated with vehicle repair costs, costs associated with human injuries and fatalities, and through including passive use values for wildlife is that we learn that the implementation of effective mitigation measures can be considered earlier and more readily than based on the cost-benefit model published in 2009.

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Vandenbrink, Stephan Christopher. Measurement of time dependent B$0\atop{d}$ $\bar{B}$$0\atop{d}$ mixing parameter using opposite side lepton and D* meson in p$\bar{p}$ collisions at √s = 1.8 TeV. Office of Scientific and Technical Information (OSTI), January 1998. http://dx.doi.org/10.2172/588553.

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