The Experts below are selected from a list of 291 Experts worldwide ranked by ideXlab platform
EHUD SHAVIV - One of the best experts on this subject based on the ideXlab platform.
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integrated modeling of pedestrian Energy Exchange and thermal comfort in urban street canyons
Building and Environment, 2007Co-Authors: David Pearlmutter, Pedro Berliner, EHUD SHAVIVAbstract:Abstract An open-air scale model is used to quantify pedestrian radiative and convective Energy Exchanges in street canyons of varying geometry, as well as surface-atmosphere Energy Exchanges above the urban canopy. A semi-empirical model based on measured data in summer is developed to link between the two levels, for the prediction of pedestrian Energy Exchange within a given street canyon based on climatic conditions above the street array. The relationships identified in the semi-empirical model are then tested with an independent data set from the winter season, demonstrating that the semi-empirical model may be used to predict the effect of street geometry on pedestrian comfort under varying seasonal conditions. Finally, the estimation of pedestrian Energy Exchange by street geometry is refined to include the effects of humidity and evaporative heat loss along with radiation and convection, and results are used to correlate between physiological Energy Exchange and thermal sensation, which is a more direct measure of human thermal comfort. The results reinforce previous findings, which indicate that in a hot-arid climate, compact street canyons can substantially reduce overall pedestrian thermal discomfort if their axis orientation is approximately north–south, while in east–west oriented canyons the effect of street proportions is much less pronounced.
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Integrated modeling of pedestrian Energy Exchange and thermal comfort in urban street canyons
Building and Environment, 2007Co-Authors: David Pearlmutter, Pedro Berliner, EHUD SHAVIVAbstract:An open-air scale model is used to quantify pedestrian radiative and convective Energy Exchanges in street canyons of varying geometry, as well as surface-atmosphere Energy Exchanges above the urban canopy. A semi-empirical model based on measured data in summer is developed to link between the two levels, for the prediction of pedestrian Energy Exchange within a given street canyon based on climatic conditions above the street array. The relationships identified in the semi-empirical model are then tested with an independent data set from the winter season, demonstrating that the semi-empirical model may be used to predict the effect of street geometry on pedestrian comfort under varying seasonal conditions. Finally, the estimation of pedestrian Energy Exchange by street geometry is refined to include the effects of humidity and evaporative heat loss along with radiation and convection, and results are used to correlate between physiological Energy Exchange and thermal sensation, which is a more direct measure of human thermal comfort. The results reinforce previous findings, which indicate that in a hot-arid climate, compact street canyons can substantially reduce overall pedestrian thermal discomfort if their axis orientation is approximately north-south, while in east-west oriented canyons the effect of street proportions is much less pronounced. © 2006 Elsevier Ltd. All rights reserved.
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Physical modeling of pedestrian Energy Exchange within the urban canopy
Building and Environment, 2006Co-Authors: David Pearlmutter, Pedro Berliner, EHUD SHAVIVAbstract:A pedestrian-centered conceptual model is used for the computation of Energy Exchange in the urban environment, based on data measured within a physical model and taking into account the effects of dimensional scaling. The physical open-air scale model, used for evaluating the influence of street canyon geometry on microclimatic conditions and pedestrian Energy Exchange within the urban canopy, enables measurement of climatic parameters with natural radiation and turbulence effects-potentially overcoming some of the limitations common to more conventional research techniques. The modeling technique is applied under typical hot-arid summer conditions in a desert region, and patterns of pedestrian Energy Exchange are compared with previous findings from full-scale measurements in a climatically similar actual urban setting. Results clearly indicate that a compact street canyon geometry may reduce pedestrian heat gain during most summer hours, but that the reduction is contingent on design aspects such as street axis orientation. Comparison of model results with full-scale measurements shows the ability of the scale model to reproduce patterns observed in full scale, and to reveal distinctions that are impractical to quantify using field studies alone. ?? 2005 Elsevier Ltd. All rights reserved.
David Pearlmutter - One of the best experts on this subject based on the ideXlab platform.
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integrated modeling of pedestrian Energy Exchange and thermal comfort in urban street canyons
Building and Environment, 2007Co-Authors: David Pearlmutter, Pedro Berliner, EHUD SHAVIVAbstract:Abstract An open-air scale model is used to quantify pedestrian radiative and convective Energy Exchanges in street canyons of varying geometry, as well as surface-atmosphere Energy Exchanges above the urban canopy. A semi-empirical model based on measured data in summer is developed to link between the two levels, for the prediction of pedestrian Energy Exchange within a given street canyon based on climatic conditions above the street array. The relationships identified in the semi-empirical model are then tested with an independent data set from the winter season, demonstrating that the semi-empirical model may be used to predict the effect of street geometry on pedestrian comfort under varying seasonal conditions. Finally, the estimation of pedestrian Energy Exchange by street geometry is refined to include the effects of humidity and evaporative heat loss along with radiation and convection, and results are used to correlate between physiological Energy Exchange and thermal sensation, which is a more direct measure of human thermal comfort. The results reinforce previous findings, which indicate that in a hot-arid climate, compact street canyons can substantially reduce overall pedestrian thermal discomfort if their axis orientation is approximately north–south, while in east–west oriented canyons the effect of street proportions is much less pronounced.
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Integrated modeling of pedestrian Energy Exchange and thermal comfort in urban street canyons
Building and Environment, 2007Co-Authors: David Pearlmutter, Pedro Berliner, EHUD SHAVIVAbstract:An open-air scale model is used to quantify pedestrian radiative and convective Energy Exchanges in street canyons of varying geometry, as well as surface-atmosphere Energy Exchanges above the urban canopy. A semi-empirical model based on measured data in summer is developed to link between the two levels, for the prediction of pedestrian Energy Exchange within a given street canyon based on climatic conditions above the street array. The relationships identified in the semi-empirical model are then tested with an independent data set from the winter season, demonstrating that the semi-empirical model may be used to predict the effect of street geometry on pedestrian comfort under varying seasonal conditions. Finally, the estimation of pedestrian Energy Exchange by street geometry is refined to include the effects of humidity and evaporative heat loss along with radiation and convection, and results are used to correlate between physiological Energy Exchange and thermal sensation, which is a more direct measure of human thermal comfort. The results reinforce previous findings, which indicate that in a hot-arid climate, compact street canyons can substantially reduce overall pedestrian thermal discomfort if their axis orientation is approximately north-south, while in east-west oriented canyons the effect of street proportions is much less pronounced. © 2006 Elsevier Ltd. All rights reserved.
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Physical modeling of pedestrian Energy Exchange within the urban canopy
Building and Environment, 2006Co-Authors: David Pearlmutter, Pedro Berliner, EHUD SHAVIVAbstract:A pedestrian-centered conceptual model is used for the computation of Energy Exchange in the urban environment, based on data measured within a physical model and taking into account the effects of dimensional scaling. The physical open-air scale model, used for evaluating the influence of street canyon geometry on microclimatic conditions and pedestrian Energy Exchange within the urban canopy, enables measurement of climatic parameters with natural radiation and turbulence effects-potentially overcoming some of the limitations common to more conventional research techniques. The modeling technique is applied under typical hot-arid summer conditions in a desert region, and patterns of pedestrian Energy Exchange are compared with previous findings from full-scale measurements in a climatically similar actual urban setting. Results clearly indicate that a compact street canyon geometry may reduce pedestrian heat gain during most summer hours, but that the reduction is contingent on design aspects such as street axis orientation. Comparison of model results with full-scale measurements shows the ability of the scale model to reproduce patterns observed in full scale, and to reveal distinctions that are impractical to quantify using field studies alone. ?? 2005 Elsevier Ltd. All rights reserved.
Pedro Berliner - One of the best experts on this subject based on the ideXlab platform.
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integrated modeling of pedestrian Energy Exchange and thermal comfort in urban street canyons
Building and Environment, 2007Co-Authors: David Pearlmutter, Pedro Berliner, EHUD SHAVIVAbstract:Abstract An open-air scale model is used to quantify pedestrian radiative and convective Energy Exchanges in street canyons of varying geometry, as well as surface-atmosphere Energy Exchanges above the urban canopy. A semi-empirical model based on measured data in summer is developed to link between the two levels, for the prediction of pedestrian Energy Exchange within a given street canyon based on climatic conditions above the street array. The relationships identified in the semi-empirical model are then tested with an independent data set from the winter season, demonstrating that the semi-empirical model may be used to predict the effect of street geometry on pedestrian comfort under varying seasonal conditions. Finally, the estimation of pedestrian Energy Exchange by street geometry is refined to include the effects of humidity and evaporative heat loss along with radiation and convection, and results are used to correlate between physiological Energy Exchange and thermal sensation, which is a more direct measure of human thermal comfort. The results reinforce previous findings, which indicate that in a hot-arid climate, compact street canyons can substantially reduce overall pedestrian thermal discomfort if their axis orientation is approximately north–south, while in east–west oriented canyons the effect of street proportions is much less pronounced.
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Integrated modeling of pedestrian Energy Exchange and thermal comfort in urban street canyons
Building and Environment, 2007Co-Authors: David Pearlmutter, Pedro Berliner, EHUD SHAVIVAbstract:An open-air scale model is used to quantify pedestrian radiative and convective Energy Exchanges in street canyons of varying geometry, as well as surface-atmosphere Energy Exchanges above the urban canopy. A semi-empirical model based on measured data in summer is developed to link between the two levels, for the prediction of pedestrian Energy Exchange within a given street canyon based on climatic conditions above the street array. The relationships identified in the semi-empirical model are then tested with an independent data set from the winter season, demonstrating that the semi-empirical model may be used to predict the effect of street geometry on pedestrian comfort under varying seasonal conditions. Finally, the estimation of pedestrian Energy Exchange by street geometry is refined to include the effects of humidity and evaporative heat loss along with radiation and convection, and results are used to correlate between physiological Energy Exchange and thermal sensation, which is a more direct measure of human thermal comfort. The results reinforce previous findings, which indicate that in a hot-arid climate, compact street canyons can substantially reduce overall pedestrian thermal discomfort if their axis orientation is approximately north-south, while in east-west oriented canyons the effect of street proportions is much less pronounced. © 2006 Elsevier Ltd. All rights reserved.
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Physical modeling of pedestrian Energy Exchange within the urban canopy
Building and Environment, 2006Co-Authors: David Pearlmutter, Pedro Berliner, EHUD SHAVIVAbstract:A pedestrian-centered conceptual model is used for the computation of Energy Exchange in the urban environment, based on data measured within a physical model and taking into account the effects of dimensional scaling. The physical open-air scale model, used for evaluating the influence of street canyon geometry on microclimatic conditions and pedestrian Energy Exchange within the urban canopy, enables measurement of climatic parameters with natural radiation and turbulence effects-potentially overcoming some of the limitations common to more conventional research techniques. The modeling technique is applied under typical hot-arid summer conditions in a desert region, and patterns of pedestrian Energy Exchange are compared with previous findings from full-scale measurements in a climatically similar actual urban setting. Results clearly indicate that a compact street canyon geometry may reduce pedestrian heat gain during most summer hours, but that the reduction is contingent on design aspects such as street axis orientation. Comparison of model results with full-scale measurements shows the ability of the scale model to reproduce patterns observed in full scale, and to reveal distinctions that are impractical to quantify using field studies alone. ?? 2005 Elsevier Ltd. All rights reserved.
Prodromos Daoutidis - One of the best experts on this subject based on the ideXlab platform.
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Microgrid/Macrogrid Energy Exchange: A Novel Market Structure and Stochastic Scheduling
IEEE Transactions on Smart Grid, 2017Co-Authors: Michael Zachar, Prodromos DaoutidisAbstract:This paper explores the stochastic scheduling of microgrids where Energy Exchange with the macrogrid must be coordinated ahead of time. In particular, a market structure is proposed in which microgrid operators make day-ahead Energy Exchange commitments. Microgrids are fined for deviating too far from commitments and a maximum difference between commitments in subsequent hours is enforced. These constraints are included to reduce the burden placed on the macrogrid by distributed generation. Under this market structure, a scheduling problem is formulated for a microgrid system consisting of microturbines, a photovoltaic array, a battery bank, and a bi-directional connection to the macrogrid. Chance-constrained optimization is used to minimize operational cost and ensure the Energy Exchange commitments are met. The problem is transformed into a mixed integer linear program, and is solved to show that these commitments can be satisfied with a high level of certainty and to illustrate inherent tradeoffs between microgrid performance and level of regulation.
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microgrid macrogrid Energy Exchange a novel market structure and stochastic scheduling
IEEE Transactions on Smart Grid, 2017Co-Authors: Michael Zachar, Prodromos DaoutidisAbstract:This paper explores the stochastic scheduling of microgrids where Energy Exchange with the macrogrid must be coordinated ahead of time. In particular, a market structure is proposed in which microgrid operators make day-ahead Energy Exchange commitments. Microgrids are fined for deviating too far from commitments and a maximum difference between commitments in subsequent hours is enforced. These constraints are included to reduce the burden placed on the macrogrid by distributed generation. Under this market structure, a scheduling problem is formulated for a microgrid system consisting of microturbines, a photovoltaic array, a battery bank, and a bi-directional connection to the macrogrid. Chance-constrained optimization is used to minimize operational cost and ensure the Energy Exchange commitments are met. The problem is transformed into a mixed integer linear program, and is solved to show that these commitments can be satisfied with a high level of certainty and to illustrate inherent tradeoffs between microgrid performance and level of regulation.
P. M. Tomchuk - One of the best experts on this subject based on the ideXlab platform.
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Electron-lattice Energy Exchange in metal nanoparticles. Quantum-kinetic and classical approaches
arXiv: Mesoscale and Nanoscale Physics, 2014Co-Authors: P. M. Tomchuk, Yevgen BilotskyAbstract:We obtained the electron-lattice Energy transfer constant in metal nanoparticles (MN), in quantum-mechanical and classical approach using the deformation potential Bardeen-Shockley and found the changes of the electron-lattice Energy Exchange (due to the finite size MN) in the quantum kinetic approach caused by the discrete phonon spectrum. The condition when the discrete phonon spectrum could be observed via the electron-phonon Energy Exchange has been obtained. It was shown that the classical approach can be generalized for metallic clusters with ballistic motion of electrons (electrons move from one potential wall to another one). In this case, the electron-lattice Energy Exchange is quasi-periodic depending on the size of the cluster, and at certain cluster size, Energy Exchange is particularly size sensitive.
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Peculiarity of electron-phonon Energy Exchange in metal nanoparticles and thin films
Surface Science, 2007Co-Authors: Y. Bilotsky, P. M. TomchukAbstract:The size dependence of electron-lattice Energy Exchange in nanoparticles has been studied. Both surface and bulk Energy Exchange parameters are examined and it is demonstrated that the bulk Energy Exchange has non-monotonic oscillations versus size of the particles. It has been found that the amplitude of such oscillations increases with decreasing a particle size until the critical size reaches Lc. These bulk interaction related oscillations disappear for the particles less than Lc, and only the surface Energy Exchange remains as the Energy flow between electrons and phonons subsystems. It has been shown that there exists an interval of particles sizes with total Energy Exchange of few orders less than in massive bulk metals. This condition is crucial for existence of hot electrons in stationary conditions in metal nanoparticles, metal island films and thin films as have been observed experimentally.
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Size effect in electron-lattice Energy Exchange in small metal particles
Surface Science, 2006Co-Authors: Y. Bilotsky, P. M. TomchukAbstract:Abstract The paper examines electron–lattice Energy Exchange in confined metal systems (metal islands). An expression is derived for the Energy, which an electron loses per unit of time to initiate acoustic oscillations in the lattice in accordance to the Cherenkov mechanism. In confined metal systems an electron moves, oscillating, from one potential wall to the other. The expression obtained for Energy Exchange converts to the generally known expression for bulk metals when the distance between the potential walls is increasing. The intensity of the bulk electron–lattice Energy Exchange oscillates and tends to zero at reaching a certain size with decrease of the distance between the walls.
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Surface electron-phonon Energy Exchange in small metallic particles
International Journal of Electronics, 1992Co-Authors: E. D. Belotskii, P. M. TomchukAbstract:Abstract In small metallic particles of certain dimensions, the well known ‘bulk’ electron-phonon Energy Exchange may become ineffective and, as a result, the governing effect proves to be that of interaction between electrons and surface modes. The paper presents a microscopic theory of such electron-surface Energy Exchange based upon a quantum-kinetic treatment.
