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    In this paper, for modeling the MR dampers, based on the phenomenological model, a normalized phenomenological model is derived through incorporating a "normalization" concept and a restructured model is proposed and realized also with incorporation of the "normalization" concept. In order to demonstrate, a multi-islands genetic algorithm (GA) is employed to identify the parameters of the restructured model, the normalized phenomenological model as well as the phenomenological model. The research results indicate that, as compared with the phenomenological model and the normalized phenomenological model, (1) the restructured model not only can effectively decrease the number of the model parameters and reduce the complexity of the model, but also can describe the nonlinear hysteretic behavior of MR dampers more accurately, and (2) the normalized phenomenological model can improve the model efficiency as compared with the phenomenological model, although not as good as the restructured model.
    Hysteresis
    Magnetorheological damper
    Citations (1)
    It has recently been pointed out that the shape of the cell nucleus is possibly controlled by forces generated inside and outside the nucleus. It has also been known that the cell nucleus shows an unusual distorted shape with some disease, such as canceration or progeria. Since the nucleus with distorted shape may be resulted in a disturbance of force balances around the nucleus, it is possible that the shape change of the nucleus is related to the functional change of the cells. In addition, cells in living tissues are exposed to an acidic environment with tumor formation and hypoxia, and they change their structures due to the acidic environment. Thus it is possible to predict the canceration by analyzing the structural change of cells under acidic stress exposure. In this study, we first established a method for analyzing the shape of the nucleus, and investigated the response of the normal fibroblasts (3T3 cells) and cervical cancer cells (HeLa cells) to acid stress, focusing on the change in the shape of the nucleus. We found that the nucleus elongation and intranuclear DNA condensation were significantly observed only in HeLa cells in an acidic environment although both types of cells elongated their adhesion area and developed their actin filaments. These results indicate that mechanical responses of nucleus under acidic stress exposure are quite different in cell types.
    HeLa
    Progeria
    Shape change
    In this paper we present the preliminary results obtained by the NA60 experiment in Indium-Indium collisions at 158 GeV.