The present paper reviews the vibro-acoustic modelling of extruded aluminium train floor structures including the state-of-the-art of its industrial applications, as well as the most recent developments on mid-frequen...The present paper reviews the vibro-acoustic modelling of extruded aluminium train floor structures including the state-of-the-art of its industrial applications, as well as the most recent developments on mid-frequency mod- elling techniques in general. With the common purpose to predict mid-frequency vibro-acoustic responses of stiffened panel structures to an acceptable accuracy at a reasonable computational cost, relevant techniques are mainly based on one of the following three types of mid-frequency vibro- acoustic modelling principles: (1) enhanced deterministic methods, (2) enhanced statistical methods, and (3) hybrid deterministic/statistical methods. It is shown that, although recent developments have led to a significant step forward in industrial applicability, mature and adequate prediction tech- niques, however, are still very much required for solving sound transmission through, and radiation from, extruded aluminium panels used on high-speed trains. Due to their great potentials for predicting mid-frequency vibro-acoustics of stiffened panel structures, two of recently developed mid-frequency modelling approaches, i.e. the so-called hybrid finite element-statistical energy analysis (FE-SEA) and hybrid wave-based method- statistical energy analysis (WBM-SEA), are then recapitulated.展开更多
By applying Lou's direct perturbation method to perturbed nonlinear Schroedinger equation and the critical nonlinear SchrSdinger equation with a small dispersion, their approximate analytical solutions including the ...By applying Lou's direct perturbation method to perturbed nonlinear Schroedinger equation and the critical nonlinear SchrSdinger equation with a small dispersion, their approximate analytical solutions including the zero-order and the first-order solutions are obtained. Based on these approximate solutions, the analytical forms of parameters of solitons are expressed and the effects of perturbations on solitons are briefly analyzed at the same time. In addition, the perturbed nonlinear Schroedinger equations is directly simulated by split-step Fourier method to check the validity of the direct perturbation method. It turns out that the analytical results given by the direct perturbation method are well supported by numerical calculations.展开更多
We extend Lou's direct perturbation method for solving the nonlinear Schrodinger equation to the case of the derivative nonlinear Schrodinger equation (DNLSE). By applying this method, different types of perturbati...We extend Lou's direct perturbation method for solving the nonlinear Schrodinger equation to the case of the derivative nonlinear Schrodinger equation (DNLSE). By applying this method, different types of perturbation solutions are obtained. Based on these approximate solutions, the analytical forms of soliton parameters, such as the velocity, the width and the initial position, are carried out and the effects of perturbation on solitons are analyzed at the same time. A numerical simulation of perturbed DNLSE finally verifies the results of the perturbation method.展开更多
Acupoint Catgut Embedding(ACE)has been proposed as a beneficial treatment for vascular dementia(VaD),but the underlying mechanisms are still unclear.The present study investigated whether ACE alleviates cognitive impa...Acupoint Catgut Embedding(ACE)has been proposed as a beneficial treatment for vascular dementia(VaD),but the underlying mechanisms are still unclear.The present study investigated whether ACE alleviates cognitive impairment by suppressing TLR4/MyD88 signaling pathway,which triggers immune-inflammatory responses in the hippocampus.V aD was established by 4-VO in male SD rats.Eight days after the operation,rats were treated with ACE once a week for 3 consecutive weeks.'T ransmission electron microscopy was used to observe the ultrastructure of nerve cells in the hippocampal area before and after ACE treatment.展开更多
基金sponsored by the NationalNatural foundation of China(Grant Nos.U1434201 and 51175300)
文摘The present paper reviews the vibro-acoustic modelling of extruded aluminium train floor structures including the state-of-the-art of its industrial applications, as well as the most recent developments on mid-frequency mod- elling techniques in general. With the common purpose to predict mid-frequency vibro-acoustic responses of stiffened panel structures to an acceptable accuracy at a reasonable computational cost, relevant techniques are mainly based on one of the following three types of mid-frequency vibro- acoustic modelling principles: (1) enhanced deterministic methods, (2) enhanced statistical methods, and (3) hybrid deterministic/statistical methods. It is shown that, although recent developments have led to a significant step forward in industrial applicability, mature and adequate prediction tech- niques, however, are still very much required for solving sound transmission through, and radiation from, extruded aluminium panels used on high-speed trains. Due to their great potentials for predicting mid-frequency vibro-acoustics of stiffened panel structures, two of recently developed mid-frequency modelling approaches, i.e. the so-called hybrid finite element-statistical energy analysis (FE-SEA) and hybrid wave-based method- statistical energy analysis (WBM-SEA), are then recapitulated.
基金The project supported by National Natural Science Foundation of China under Grant No. 10575087 and the Natural Science Foundation of Zhejiang Province of China under Grant No. 102053
文摘By applying Lou's direct perturbation method to perturbed nonlinear Schroedinger equation and the critical nonlinear SchrSdinger equation with a small dispersion, their approximate analytical solutions including the zero-order and the first-order solutions are obtained. Based on these approximate solutions, the analytical forms of parameters of solitons are expressed and the effects of perturbations on solitons are briefly analyzed at the same time. In addition, the perturbed nonlinear Schroedinger equations is directly simulated by split-step Fourier method to check the validity of the direct perturbation method. It turns out that the analytical results given by the direct perturbation method are well supported by numerical calculations.
基金supported by National Natural Science Foundation of China under Grant No.10575087
文摘We extend Lou's direct perturbation method for solving the nonlinear Schrodinger equation to the case of the derivative nonlinear Schrodinger equation (DNLSE). By applying this method, different types of perturbation solutions are obtained. Based on these approximate solutions, the analytical forms of soliton parameters, such as the velocity, the width and the initial position, are carried out and the effects of perturbation on solitons are analyzed at the same time. A numerical simulation of perturbed DNLSE finally verifies the results of the perturbation method.
文摘Acupoint Catgut Embedding(ACE)has been proposed as a beneficial treatment for vascular dementia(VaD),but the underlying mechanisms are still unclear.The present study investigated whether ACE alleviates cognitive impairment by suppressing TLR4/MyD88 signaling pathway,which triggers immune-inflammatory responses in the hippocampus.V aD was established by 4-VO in male SD rats.Eight days after the operation,rats were treated with ACE once a week for 3 consecutive weeks.'T ransmission electron microscopy was used to observe the ultrastructure of nerve cells in the hippocampal area before and after ACE treatment.