The Experts below are selected from a list of 2190 Experts worldwide ranked by ideXlab platform

A. I. Flossmann - One of the best experts on this subject based on the ideXlab platform.

  • Mesoscale Meteorological Simulations In Paris: Comparisons With Observations During The Experiment Eclap
    Boundary-Layer Meteorology, 2001
    Co-Authors: F. Troude, E. Dupont, B. Carissmo, A. I. Flossmann
    Abstract:

    This paper analyses the meteorological numerical simulation in Paris during two days (March 10 and 13, 1995) observed during ECLAP (Etude de la Couche Limite en Agglomération Parisienne– the boundary-layer study of the Paris area), a recent measurement campaign over the Paris area, in which both in-situ and remote-sensing devices at urban and rural locations have been deployed in addition to the operational meteorological network. The chosen days are well documented and correspond to different meteorological situations leading to pollution events (regarding wind direction, cloud cover, surface and synoptic inversion strength).Comparisons of three-dimensional mesoscale model results with the ECLAP observation data are presented, focusing on the temperature field and turbulent fluxes along with the urban heat island and the evolution of the mixing height. It is shown that the model correctly reproduces the main characteristics of the temperature field, its diurnal evolution (near the ground and higher up) especially the gradient between Paris and the surrounding countryside. The mixing-height evolutions are in a good agreement with the observations and the model is also able to reproduce the turbulent features of the atmosphere. The small difference observed between the urban and rural mixing-height evolution is also well reproduced.

  • MESOSCALE METEOROLOGICAL SIMULATIONS IN PARIS: COMPARISONS WITH OBSERVATIONS DURING THE EXPERIMENT ECLAP
    Boundary-Layer Meteorology, 2001
    Co-Authors: F. Troude, E. Dupont, B. Carissmo, A. I. Flossmann
    Abstract:

    This paper analyses the meteorological numerical simulation in Paris during two days (March 10 and 13, 1995) observed during ECLAP (Etude de la Couche Limite en Agglomeration Parisienne– the boundary-layer study of the Paris area), a recent measurement campaign over the Paris area, in which both in-situ and remote-sensing devices at urban and rural locations have been deployed in addition to the operational meteorological network. The chosen days are well documented and correspond to different meteorological situations leading to pollution events (regarding wind direction, cloud cover, surface and synoptic inversion strength).Comparisons of three-dimensional mesoscale model results with the ECLAP observation data are presented, focusing on the temperature field and turbulent fluxes along with the urban heat island and the evolution of the mixing height. It is shown that the model correctly reproduces the main characteristics of the temperature field, its diurnal evolution (near the ground and higher up) especially the gradient between Paris and the surrounding countryside. The mixing-height evolutions are in a good agreement with the observations and the model is also able to reproduce the turbulent features of the atmosphere. The small difference observed between the urban and rural mixing-height evolution is also well reproduced.

Takashi Tanaka - One of the best experts on this subject based on the ideXlab platform.

  • Evolution of auroral substorm as viewed from MHD simulations: dynamics, energy transfer and energy conversion
    Reviews of Modern Plasma Physics, 2020
    Co-Authors: Yusuke Ebihara, Takashi Tanaka
    Abstract:

    An auroral substorm is a visual manifestation of large-scale, transient disturbances taking place in space surrounding the Earth, and is one of the central issues in the space plasma physics. While a number of studies have been conducted, a unified picture of the overall evolution of the auroral substorm has not been drawn. This paper is aimed to overview the recently obtained results of global magnetohydrodynamics (MHD) simulations in a context of a priori presence of anomalous resistivity leading to magnetic reconnection, and to illuminate what the global MHD simulation can sufficiently reproduce the auroral transients during the auroral substorm. Some auroral transients are found to be seamlessly reproduced by the MHD simulation, including complicated auroral structures moving equatorward during the growth phase, auroral brightening starting to appear near the equatorward border of the preexisting auroral arc, and an auroral surge traveling westward. Possible energy transfer and conversion from the solar wind to the Earth are also overviewed on the basis of the MHD simulation. At least, 4 dynamo regions appear sequentially in the course of the development of the auroral substorm. Although the MHD simulation reproduces some transients, further studies are needed to investigate the role of kinetic processes.

  • Evolution of auroral substorm as viewed from MHD simulations: dynamics, energy transfer and energy conversion
    Reviews of Modern Plasma Physics, 2020
    Co-Authors: Yusuke Ebihara, Takashi Tanaka
    Abstract:

    An auroral substorm is a visual manifestation of large-scale, transient disturbances taking place in space surrounding the Earth, and is one of the central issues in the space plasma physics. While a number of studies have been conducted, a unified picture of the overall evolution of the auroral substorm has not been drawn. This paper is aimed to overview the recently obtained results of global magnetohydrodynamics (MHD) simulations in a context of a priori presence of anomalous resistivity leading to magnetic reconnection, and to illuminate what the global MHD simulation can sufficiently reproduce the auroral transients during the auroral substorm. Some auroral transients are found to be seamlessly reproduced by the MHD simulation, including complicated auroral structures moving equatorward during the growth phase, auroral brightening starting to appear near the equatorward border of the preexisting auroral arc, and an auroral surge traveling westward. Possible energy transfer and conversion from the solar wind to the Earth are also overviewed on the basis of the MHD simulation. At least, 4 dynamo regions appear sequentially in the course of the development of the auroral substorm. Although the MHD simulation reproduces some transients, further studies are needed to investigate the role of kinetic processes.

Takeshi Aihara - One of the best experts on this subject based on the ideXlab platform.

  • diverse background activities hidden in power law spontaneous activity of hippocampal ca3 slice culture
    Soft Computing, 2012
    Co-Authors: Toshikazu Samura, Yasuomi D Sato, Yuji Ikegaya, Hatsuo Hayashi, Takeshi Aihara
    Abstract:

    The hippocampal CA3 slice culture causes a power-law distributed neuronal activity spontaneously. In computer simulations, we reproduce three stochastic properties (synchrony size, spike-count rate and inter-spike interval) of the spontaneous activity observed from the CA3 slice cultures. When the background activity of a neuron, that is not the activity driven by synaptic inputs, is uniform in every neuron, the stochastic properties are not reproduced at the same time. However, when the background activity of a neuron differs in every neuron, the stochastic properties are simultaneously reproduced. These results suggest that the diverse background activities hide in the spontaneous activity of hippocampal CA3 slice culture. It has been suggested that a neuronal network causing power-law distributed neuronal activity optimizes input/output processing. The hippocampal CA3 slice culture causing power-law spontaneous activity may optimize input/output processing on the diverse background activities.

  • SCIS&ISIS - Diverse background activities hidden in power-law spontaneous activity of hippocampal CA3 slice culture
    The 6th International Conference on Soft Computing and Intelligent Systems and The 13th International Symposium on Advanced Intelligence Systems, 2012
    Co-Authors: Toshikazu Samura, Yasuomi D Sato, Yuji Ikegaya, Hatsuo Hayashi, Takeshi Aihara
    Abstract:

    The hippocampal CA3 slice culture causes a power-law distributed neuronal activity spontaneously. In computer simulations, we reproduce three stochastic properties (synchrony size, spike-count rate and inter-spike interval) of the spontaneous activity observed from the CA3 slice cultures. When the background activity of a neuron, that is not the activity driven by synaptic inputs, is uniform in every neuron, the stochastic properties are not reproduced at the same time. However, when the background activity of a neuron differs in every neuron, the stochastic properties are simultaneously reproduced. These results suggest that the diverse background activities hide in the spontaneous activity of hippocampal CA3 slice culture. It has been suggested that a neuronal network causing power-law distributed neuronal activity optimizes input/output processing. The hippocampal CA3 slice culture causing power-law spontaneous activity may optimize input/output processing on the diverse background activities.

F. Troude - One of the best experts on this subject based on the ideXlab platform.

  • Mesoscale Meteorological Simulations In Paris: Comparisons With Observations During The Experiment Eclap
    Boundary-Layer Meteorology, 2001
    Co-Authors: F. Troude, E. Dupont, B. Carissmo, A. I. Flossmann
    Abstract:

    This paper analyses the meteorological numerical simulation in Paris during two days (March 10 and 13, 1995) observed during ECLAP (Etude de la Couche Limite en Agglomération Parisienne– the boundary-layer study of the Paris area), a recent measurement campaign over the Paris area, in which both in-situ and remote-sensing devices at urban and rural locations have been deployed in addition to the operational meteorological network. The chosen days are well documented and correspond to different meteorological situations leading to pollution events (regarding wind direction, cloud cover, surface and synoptic inversion strength).Comparisons of three-dimensional mesoscale model results with the ECLAP observation data are presented, focusing on the temperature field and turbulent fluxes along with the urban heat island and the evolution of the mixing height. It is shown that the model correctly reproduces the main characteristics of the temperature field, its diurnal evolution (near the ground and higher up) especially the gradient between Paris and the surrounding countryside. The mixing-height evolutions are in a good agreement with the observations and the model is also able to reproduce the turbulent features of the atmosphere. The small difference observed between the urban and rural mixing-height evolution is also well reproduced.

  • MESOSCALE METEOROLOGICAL SIMULATIONS IN PARIS: COMPARISONS WITH OBSERVATIONS DURING THE EXPERIMENT ECLAP
    Boundary-Layer Meteorology, 2001
    Co-Authors: F. Troude, E. Dupont, B. Carissmo, A. I. Flossmann
    Abstract:

    This paper analyses the meteorological numerical simulation in Paris during two days (March 10 and 13, 1995) observed during ECLAP (Etude de la Couche Limite en Agglomeration Parisienne– the boundary-layer study of the Paris area), a recent measurement campaign over the Paris area, in which both in-situ and remote-sensing devices at urban and rural locations have been deployed in addition to the operational meteorological network. The chosen days are well documented and correspond to different meteorological situations leading to pollution events (regarding wind direction, cloud cover, surface and synoptic inversion strength).Comparisons of three-dimensional mesoscale model results with the ECLAP observation data are presented, focusing on the temperature field and turbulent fluxes along with the urban heat island and the evolution of the mixing height. It is shown that the model correctly reproduces the main characteristics of the temperature field, its diurnal evolution (near the ground and higher up) especially the gradient between Paris and the surrounding countryside. The mixing-height evolutions are in a good agreement with the observations and the model is also able to reproduce the turbulent features of the atmosphere. The small difference observed between the urban and rural mixing-height evolution is also well reproduced.

Yusuke Ebihara - One of the best experts on this subject based on the ideXlab platform.

  • Evolution of auroral substorm as viewed from MHD simulations: dynamics, energy transfer and energy conversion
    Reviews of Modern Plasma Physics, 2020
    Co-Authors: Yusuke Ebihara, Takashi Tanaka
    Abstract:

    An auroral substorm is a visual manifestation of large-scale, transient disturbances taking place in space surrounding the Earth, and is one of the central issues in the space plasma physics. While a number of studies have been conducted, a unified picture of the overall evolution of the auroral substorm has not been drawn. This paper is aimed to overview the recently obtained results of global magnetohydrodynamics (MHD) simulations in a context of a priori presence of anomalous resistivity leading to magnetic reconnection, and to illuminate what the global MHD simulation can sufficiently reproduce the auroral transients during the auroral substorm. Some auroral transients are found to be seamlessly reproduced by the MHD simulation, including complicated auroral structures moving equatorward during the growth phase, auroral brightening starting to appear near the equatorward border of the preexisting auroral arc, and an auroral surge traveling westward. Possible energy transfer and conversion from the solar wind to the Earth are also overviewed on the basis of the MHD simulation. At least, 4 dynamo regions appear sequentially in the course of the development of the auroral substorm. Although the MHD simulation reproduces some transients, further studies are needed to investigate the role of kinetic processes.

  • Evolution of auroral substorm as viewed from MHD simulations: dynamics, energy transfer and energy conversion
    Reviews of Modern Plasma Physics, 2020
    Co-Authors: Yusuke Ebihara, Takashi Tanaka
    Abstract:

    An auroral substorm is a visual manifestation of large-scale, transient disturbances taking place in space surrounding the Earth, and is one of the central issues in the space plasma physics. While a number of studies have been conducted, a unified picture of the overall evolution of the auroral substorm has not been drawn. This paper is aimed to overview the recently obtained results of global magnetohydrodynamics (MHD) simulations in a context of a priori presence of anomalous resistivity leading to magnetic reconnection, and to illuminate what the global MHD simulation can sufficiently reproduce the auroral transients during the auroral substorm. Some auroral transients are found to be seamlessly reproduced by the MHD simulation, including complicated auroral structures moving equatorward during the growth phase, auroral brightening starting to appear near the equatorward border of the preexisting auroral arc, and an auroral surge traveling westward. Possible energy transfer and conversion from the solar wind to the Earth are also overviewed on the basis of the MHD simulation. At least, 4 dynamo regions appear sequentially in the course of the development of the auroral substorm. Although the MHD simulation reproduces some transients, further studies are needed to investigate the role of kinetic processes.