5,499 research outputs found
Heavy Quark Effective Theory on the Light Front
The light-front heavy quark effective theory is derived to all orders in
. In the limit , the theory exhibits the familiar
heavy quark spin-flavor symmetry. This new formalism permits a straightforward
canonical quantization to all orders in ; moreover, higher order terms
have rather simple operator structures. The light-front heavy quark effective
theory can serve as an useful framework for the study of non-perturbative QCD
dynamics of heavy hadron bound states.Comment: 11 pages, revtex, no figure
Effect of stirring on the safety of flammable liquid mixtures
Flash point is the most important variable employed to characterize fire and explosion hazard of liquids. The models developed for predicting the flash point of partially miscible mixtures in the literature to date are all based on the assumption of liquid-liquid equilibrium. In real-world environments, however, the liquid-liquid equilibrium assumption does not always hold, such as the collection or accumulation of waste solvents without stirring, where complete stirring for a period of time is usually used to ensure the liquid phases being in equilibrium. This study investigated the effect of stirring on the flash point behavior of binary partially miscible mixtures. Two series of partially miscible binary mixtures were employed to elucidate the effect of stirring. The first series was aqueous-organic mixtures, including water + 1-butanol, water + 2-butanol, water + isobutanol, water + 1-pentanol, and water + octane ; the second series was the mixtures of two flammable solvents, which included methanol + decane, methanol + 2,2,4-trimethylpentane, and methanol + octane. Results reveal that for binary aqueous-organic solutions the flash-point values of unstirred mixtures were located between those of the completely stirred mixtures and those of the flammable component. Therefore, risk assessment could be done based on the flammable component flash point value. However, for the assurance of safety, it is suggested to completely stir those mixtures before handling to reduce the risk
ON THE EQUIVALENCE OF IMPORT TARIFF AND QUOTA: THE CASE OF RICE IMPORT IN TAIWAN
This paper extends the existing theory on the equivalence of import tariff and quota. If the equivalence is defined on the domestic price level (weak equivalence), then either the zero conjectural variation for domestic country or a perfectly competitive market will be sufficient to support this equivalence. If the equivalence is defined both on the same domestic price level as well as tariff rate (strong equivalence), then the conditions are that either domestic country acts as a Cournot competitor and foreign country is a price taker, or both domestic and foreign country are price takers. An empirical spatial-equilibrium trade model is constructed to simulate the impacts of import tariff and quota. Using Taiwan¡¦s rice import as an example, the empirical results show that if Taiwan switches from the quota system to tariff system, the domestic rice price as well as total social welfare can be increased given the same import volume.International Relations/Trade,
Minimal dynamic modeling of gesture of danse (toward a model based on knowledge engraved within the body)
International audienceDance movement is not only to perform a desired motion but also to feel and to transmit sensation (expression) by body and energy. Dynamic models are particularly adequate for this objective. In this paper, we present a set of dynamic models based on physically-based particle modeling
A dynamic life of cause : a concept and models using for computer-assisted choreography
ISSN: 1071-4391 - http://www.leoalmanac.org/leonardo-electronic-almanac-volume-15-no-5-6-may-june-2007/International audienceThe authors propose a series of physics-based models relating to dance verbs. These physics-based and dance verb-relating models generate dance movements dynamically instead of reserve of motion data. In terms of movement representation, these models are useful for computer-assisted choreography and for character animation. In terms of movement understanding, these models based on physics are useful as well by manipulating the cause-effect relation of modeling. In other words, these models can be a kind of predictive models for human behavioral research. In the article, the authors explain mainly the concept of ''a dynamic life of cause'' relating to both physics-based models and dance verbs. Furthermore, the authors propose composing ''a dynamic life of cause'' for movement composition
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