The Experts below are selected from a list of 377580 Experts worldwide ranked by ideXlab platform
Timothy Ibell - One of the best experts on this subject based on the ideXlab platform.
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dataset for rational whole life carbon assessment using a dynamic climate model comparison of a concrete steel and timber Building Structure
Structures, 2020Co-Authors: William Hawkins, Sam Cooper, Aurimas Bukauskas, S R Allen, Jonathan Roynon, Timothy IbellAbstract:This dataset concerns a research study on the embodied carbon assessment of Building Structures. It includes the numerical data which is plotted in the journal paper titled "Embodied carbon assessment using a dynamic climate model: Case-study comparison of a concrete, steel and timber Building Structure". The data is in .csv format and is output from a numerical dynamic life cycle assessment, which models the climate impacts of greenhouse gas emissions. Each file relates to a figure in the associated paper, with full descriptions in the 'read-me' file.
Izuru Takewaki - One of the best experts on this subject based on the ideXlab platform.
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bound of earthquake input energy to Building Structure considering shallow and deep ground uncertainties
Soil Dynamics and Earthquake Engineering, 2015Co-Authors: M Taniguchi, Izuru TakewakiAbstract:Abstract The bound of earthquake input energy to Building Structures is clarified by considering shallow and deep ground uncertainties and soil–Structure interaction. The ground motion amplification in the shallow and deep ground is described by a one-dimensional wave propagation theory. The constant input energy property to a swaying–rocking model with respect to the free-field ground surface input regardless of the soil property is used effectively to derive a bound. An extension of the previous theory for the engineering bedrock surface motion to a general earthquake ground motion model at the earthquake bedrock is made by taking full advantage of the above-mentioned input energy constant property. It is shown through numerical examples that a tight bound of earthquake input energy can be derived for the shallow and deep ground uncertainties.
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Critical double impulse input and bound of earthquake input energy to Building Structure
Frontiers in Built Environment, 2015Co-Authors: Kotaro Kojima, Kohei Fujita, Izuru TakewakiAbstract:A theory of earthquake input energy to Building Structures under single impulse is useful for disclosing the property of energy transfer function. This property shows that the area of the energy transfer function is constant irrespective of natural period and damping of Building Structures. However single impulse may be unrealistic from a certain viewpoint because the frequency characteristic of input cannot be expressed by this input. In order to resolve such issue, a double impulse is introduced in this paper. The frequency characteristic of the Fourier amplitude of the double impulse is found in an explicit manner and a critical excitation problem is formulated with an interval of two impulses as a variable. The solution to that critical excitation problem is derived. An upper bound of the earthquake input energy is then derived by taking full advantage of the property of the energy transfer function that the area of the energy transfer function is constant. The relation of the double impulse to the corresponding one-cycle sinusoidal wave as a representative of near-fault pulse-type waves is also investigated.
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mechanism and bounding of earthquake energy input to Building Structure on surface ground subjected to engineering bedrock motion
Soil Dynamics and Earthquake Engineering, 2015Co-Authors: Kotaro Kojima, Kazuhiro Sakaguchi, Izuru TakewakiAbstract:Abstract The mechanism of earthquake energy input to Building Structures is clarified by considering the surface ground amplification and soil–Structure interaction. The earthquake input energies to superStructures, soil–foundation systems and total swaying–rocking system are obtained by taking the corresponding appropriate free bodies into account and defining the energy transfer functions. It has been made clear that, when the ground surface motion is white, the input energy to the swaying–rocking model is constant regardless of the soil property (input energy constant property). The upper bound of earthquake input energy to the swaying–rocking model is derived for the model including the surface ground amplification by taking full advantage of the above-mentioned input energy constant property and introducing the envelope function for the transfer function of the surface ground amplification. Extension of the theory to a general earthquake ground motion model at the engineering bedrock is also made by taking full advantage of the above-mentioned input energy constant property.
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critical excitation for earthquake energy input in Structure pile soil system
Critical Excitation Methods in Earthquake Engineering (Second edition), 2013Co-Authors: Izuru TakewakiAbstract:This chapter discusses a new method in the frequency domain for the computation of earthquake input energies both to a Structure–pile system and a Structure only. In investigating the energy flow in the Structure–pile system, many difficulties arise resulting from the dynamic interaction between the pile and the surrounding soil. It can be shown that the formulation of the earthquake input energy in the frequency domain is effective for deriving the earthquake input energy both to a Structure–pile system and a Structure only. An efficient continuum model consisting of a dynamic Winkler-type soil element and a pile is used to express the dynamic behavior of the Structure–pile system accurately. The formulation of the earthquake input energy in the frequency domain is appropriate for introducing the frequency-dependent vibration property of the surface ground. It is demonstrated that the present formulation is effective for various input levels and ground properties. The energy input mechanism in the Building Structure–pile system can be well described by the newly introduced energy transfer function. The chapter introduces a new concept called the input energy densities at various underground levels, which is used to disclose the energy input mechanism in the Building Structure–pile system.
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chapter 11 critical excitation for earthquake energy input in Structure pile soil system
Critical Excitation Methods in Earthquake Engineering, 2007Co-Authors: Izuru TakewakiAbstract:Publisher Summary This chapter discusses a new method in the frequency domain for the computation of earthquake input energies both to a Structure–pile system and a Structure only. In investigating the energy flow in the Structure–pile system, many difficulties arise resulting from the dynamic interaction between the pile and the surrounding soil. It can be shown that the formulation of the earthquake input energy in the frequency domain is effective for deriving the earthquake input energy both to a Structure–pile system and a Structure only. An efficient continuum model consisting of a dynamic Winkler-type soil element and a pile is used to express the dynamic behavior of the Structure–pile system accurately. The formulation of the earthquake input energy in the frequency domain is appropriate for introducing the frequency-dependent vibration property of the surface ground. It is demonstrated that the present formulation is effective for various input levels and ground properties. The energy input mechanism in the Building Structure–pile system can be well described by the newly introduced energy transfer function. The chapter introduces a new concept called the input energy densities at various underground levels, which is used to disclose the energy input mechanism in the Building Structure–pile system.
William Hawkins - One of the best experts on this subject based on the ideXlab platform.
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dataset for rational whole life carbon assessment using a dynamic climate model comparison of a concrete steel and timber Building Structure
Structures, 2020Co-Authors: William Hawkins, Sam Cooper, Aurimas Bukauskas, S R Allen, Jonathan Roynon, Timothy IbellAbstract:This dataset concerns a research study on the embodied carbon assessment of Building Structures. It includes the numerical data which is plotted in the journal paper titled "Embodied carbon assessment using a dynamic climate model: Case-study comparison of a concrete, steel and timber Building Structure". The data is in .csv format and is output from a numerical dynamic life cycle assessment, which models the climate impacts of greenhouse gas emissions. Each file relates to a figure in the associated paper, with full descriptions in the 'read-me' file.
Jiaqiang Wang - One of the best experts on this subject based on the ideXlab platform.
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application of model based control strategy to hybrid free cooling system with latent heat thermal energy storage for tbss
Energy and Buildings, 2018Co-Authors: Qua Zhang, Jiaqiang Wang, Xiaoming Che, Sungmi YooAbstract:Abstract This paper explored the application of model predictive control (MPC) technology to the TBSs hybrid free cooling system with latent heat thermal energy storage (LHTES) unit for minimizing the Building operational cost without sacrificing temperature requirements. First, the system was briefly introduced and the dynamic thermal process models of Building Structure and LHTES unit were developed. Then, a hierarchical control Structure with dynamic multi-swarm particle swarm optimization was presented to address the dimensional challenge and discontinuities in control variables. Due to the considerable decrease of optimization variable space, the method presented in this paper enables long-term simulation and application in a real controller. Simulations were carried out based on a typical TBS Building located in Beijing, China. The total energy consumption of the cooling system and the control quality of indoor air temperature were used as the criteria to evaluate the performance. Compared to a defined baseline case, the optimal control method can achieve significant energy saving, i.e. up to 18%. The impacts of the size of LHTES unit and the type of Building Structure were discussed, as well. The active and passive heat capacity both played a catalytic role in performance of MPC. Additionally, an uncertainty analysis demonstrated that the proposed approach has strong robustness and can handle quite high errors in forecasting Building disturbances from energy consumption level. In summary, the knowledge and use of the plant system and future disturbances make MPC a powerful control tool for TBS Buildings for maximizing the use of renewable energy sources.
Reza Langari - One of the best experts on this subject based on the ideXlab platform.
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model based multi input multi output supervisory semi active nonlinear fuzzy controller
Computer-aided Civil and Infrastructure Engineering, 2010Co-Authors: Yeesock Kim, Stefan Hurlebaus, Reza LangariAbstract:: The authors recently proposed a new multi-input, single-output (MISO) semi-active fuzzy controller for vibration control of seismically excited small-scale Buildings. In this article, the previously proposed MISO control system is advanced to a multi-input, multi-output (MIMO) control system through integration of a set of model-based fuzzy controllers that are formulated in terms of linear matrix inequalities (LMIs) such that the global asymptotical stability is guaranteed and the performance on transient responses is also satisfied. The set of model-based fuzzy controllers is divided into two groups: lower level controllers and a higher level coordinator. The lower level fuzzy controllers are designed using acceleration and drift responses; while velocity information is used for the higher level controller. To demonstrate the effectiveness of the proposed approach, an eight-story Building Structure employing magnetorheological (MR) dampers is studied. It is demonstrated from comparison of the uncontrolled and semi-active controlled responses that the proposed design framework is effective in vibration reduction of a Building Structure equipped with MR dampers.
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semiactive nonlinear control of a Building with a magnetorheological damper system
Mechanical Systems and Signal Processing, 2009Co-Authors: Reza Langari, Stefan HurlebausAbstract:Abstract This paper proposes a linear matrix inequality (LMI)-based systematic design methodology for nonlinear control of Building Structures equipped with a magnetorheological (MR) damper. This approach considers stability performance as well as transient characteristics in a unified framework. First, multiple Lyapunov-based controllers are designed via LMIs such that global asymptotical stability of the Building Structure is guaranteed and the performance on transient responses is also satisfied. Such Lyapunov-based state feedback controllers are converted into output feedback regulators using a set of Kalman estimators. Then, these Lyapunov-based controllers and Kalman observers are integrated into a global nonlinear control system via fuzzy logic. To demonstrate the effectiveness of the proposed approach, a three-story Building Structure employing an MR damper is studied. The performance of the nonlinear control system is compared with that of a traditional linear optimal controller, i.e., H2/linear quadratic Gaussian (LQG), while the uncontrolled system response is used as the baseline. It is demonstrated from comparison of the uncontrolled and semiactive controlled responses that the proposed nonlinear control system design framework is effective in reducing the vibration of a seismically excited Building Structure equipped with an MR damper. Furthermore, the newly developed controller is more effective in mitigating responses of the Structure than the H2/LQG controller.
