In order to deal with modeling problem of a pressure balance system with time-delay, nonlinear, time-varying and uncertain characteristics, an intelligent modeling procedure is proposed, which is based on artificial n...In order to deal with modeling problem of a pressure balance system with time-delay, nonlinear, time-varying and uncertain characteristics, an intelligent modeling procedure is proposed, which is based on artificial neural network(ANN) and input-output data of the system during shield tunneling and can overcome the precision problem in mechanistic modeling(MM) approach. The computational results show that the training algorithm with Gauss-Newton optimization has fast convergent speed. The experimental investigation indicates that, compared with mechanistic modeling approach, intelligent modeling procedure can obviously increase the precision in both soil pressure fitting and forecasting period. The effectiveness and accuracy of proposed intelligent modeling procedure are verified in laboratory tests.展开更多
Wave transmission and overtopping around nearshore breakwaters can have significant influence on the transmitted wave parameters,which affects wave conditions and sediment transportation and becomes the focus of desig...Wave transmission and overtopping around nearshore breakwaters can have significant influence on the transmitted wave parameters,which affects wave conditions and sediment transportation and becomes the focus of design in engineering.The objective of this paper is to present a simplified model to estimate these important wave parameters.This paper describes the incorporation of wave transmission and overtopping module into a wave model for multi-directional random wave transformation based on energy balance equation with the consideration of wave shoaling,refraction,diffraction,reflection and breaking.Wen's frequency spectrum and non-linear dispersion relation are also included in this model.The influence of wave parameters of transmitted waves through a smooth submerged breakwater has been considered in this model with an improved description of the transmitted wave spectrum of van der Meer et al.(2000) by Carevic et al.(2013).This improved wave model has been validated through available laboratory experiments.Then the verified model is applied to investigate the effect of wave transmission and overtopping on wave heights behind low-crested breakwaters in a project for nearshore area.Numerical calculations are carried out with and without consideration of the wave transmission and overtopping,and comparison of them indicates that there is a considerable difference in wave height and thus it is important to include wave transmission and overtopping in modelling nearshore wave field with the presence of low-crested breakwaters.Therefore,this model can provide a general estimate of the desired wave field parameters,which is adequate for engineers at the preliminary design stage of low-crested breakwaters.展开更多
Kinetics of adsorption of furfural from aqueous solution on zeolite： ZSM-5 （Zeolite Socony Mobil-5）, surface have been studied at room temperature. For evaluation of adsorption properties and mechanism, the adsorpt...Kinetics of adsorption of furfural from aqueous solution on zeolite： ZSM-5 （Zeolite Socony Mobil-5）, surface have been studied at room temperature. For evaluation of adsorption properties and mechanism, the adsorption isotherms have been described. Adsorption data have been fitted by the models Langmuir, Freundlich, BET （Brunauer-Emmett-Teller）, Redlich-Peterson, T6th and Dubinin-Radushkevitch. Adsorption capacity of zeolite for furfural in the studied range of concentrations （0-100 mmol/L） is found to reach 60 mg/g. The Langmuir and BET models are found to be the best for experimental data description with Re= 0.9959 and 0.9994, respectively. The Dubinin-Radushkevitch model has been used for determination of the equation constants. The latter has been applied further for calculation of energy of adsorption of furfural on zeolite ZSM-5, which is equal to 11 kJ/mol, indicating the chemical nature of adsorption interaction. The kinetics data have been modeled using pseudo-first-order and pseudo-second-order models. The kinetic sorption offered rather good fit with pseudo-second-order model with the Re value of 0.9821. The rate-limiting step is found to be intraparticle diffusion. Zeolite ZSM-5 is convenient sorbent for furfural uptake within the tested concentration range.展开更多
基金Project(2013CB035402) supported by the National Basic Research Program of ChinaProjects(51105048,51209028) supported by the National Natural Science Foundation of China
文摘In order to deal with modeling problem of a pressure balance system with time-delay, nonlinear, time-varying and uncertain characteristics, an intelligent modeling procedure is proposed, which is based on artificial neural network(ANN) and input-output data of the system during shield tunneling and can overcome the precision problem in mechanistic modeling(MM) approach. The computational results show that the training algorithm with Gauss-Newton optimization has fast convergent speed. The experimental investigation indicates that, compared with mechanistic modeling approach, intelligent modeling procedure can obviously increase the precision in both soil pressure fitting and forecasting period. The effectiveness and accuracy of proposed intelligent modeling procedure are verified in laboratory tests.
基金supported by the NSFC-Shandong Joint Fund Project(No.U1706226)Research Award Fund for Outstanding Young and Middle-aged Scientists of Shandong Province(No.ZR2016EEB06)the Scientific Research Foundation of Shandong University of Science and Technology for Recruited Talents
文摘Wave transmission and overtopping around nearshore breakwaters can have significant influence on the transmitted wave parameters,which affects wave conditions and sediment transportation and becomes the focus of design in engineering.The objective of this paper is to present a simplified model to estimate these important wave parameters.This paper describes the incorporation of wave transmission and overtopping module into a wave model for multi-directional random wave transformation based on energy balance equation with the consideration of wave shoaling,refraction,diffraction,reflection and breaking.Wen's frequency spectrum and non-linear dispersion relation are also included in this model.The influence of wave parameters of transmitted waves through a smooth submerged breakwater has been considered in this model with an improved description of the transmitted wave spectrum of van der Meer et al.(2000) by Carevic et al.(2013).This improved wave model has been validated through available laboratory experiments.Then the verified model is applied to investigate the effect of wave transmission and overtopping on wave heights behind low-crested breakwaters in a project for nearshore area.Numerical calculations are carried out with and without consideration of the wave transmission and overtopping,and comparison of them indicates that there is a considerable difference in wave height and thus it is important to include wave transmission and overtopping in modelling nearshore wave field with the presence of low-crested breakwaters.Therefore,this model can provide a general estimate of the desired wave field parameters,which is adequate for engineers at the preliminary design stage of low-crested breakwaters.
文摘Kinetics of adsorption of furfural from aqueous solution on zeolite： ZSM-5 （Zeolite Socony Mobil-5）, surface have been studied at room temperature. For evaluation of adsorption properties and mechanism, the adsorption isotherms have been described. Adsorption data have been fitted by the models Langmuir, Freundlich, BET （Brunauer-Emmett-Teller）, Redlich-Peterson, T6th and Dubinin-Radushkevitch. Adsorption capacity of zeolite for furfural in the studied range of concentrations （0-100 mmol/L） is found to reach 60 mg/g. The Langmuir and BET models are found to be the best for experimental data description with Re= 0.9959 and 0.9994, respectively. The Dubinin-Radushkevitch model has been used for determination of the equation constants. The latter has been applied further for calculation of energy of adsorption of furfural on zeolite ZSM-5, which is equal to 11 kJ/mol, indicating the chemical nature of adsorption interaction. The kinetics data have been modeled using pseudo-first-order and pseudo-second-order models. The kinetic sorption offered rather good fit with pseudo-second-order model with the Re value of 0.9821. The rate-limiting step is found to be intraparticle diffusion. Zeolite ZSM-5 is convenient sorbent for furfural uptake within the tested concentration range.
