Model Reduction Methods for High-Rise Buildings with Active Mass Damper Control Systems

To improve the performance of an active mass damper control system,the controller should be designed based on a reduced-order model. An improved method based on balanced truncation method was proposed to reduce the dimension of high-rise buildings,and was compared with other widely used reduction methods by using a framework with ten floors. This optimized method has improvement of reduction process and choice of the order. Based on the reduced-order model obtained by the improved method and pole-assignment algorithm,a controller was designed. Finally,a comparative analysis of structural responses,transfer functions,and poles was conducted on an actual high-rise building. The results show the effectiveness of the improved method.

Finite Element Simulation of Radial Tire Building and Shaping Processes Using an Elasto-Viscoplastic Model

The comprehensive tire building and shaping processes are investigated through the finite element method(FEM)in this article.The mechanical properties of the uncured rubber from different tire components are investigated through cyclic loading-unloading experiments under different strain rates.Based on the experiments,an elastoviscoplastic constitutive model is adopted to describe themechanical behaviors of the uncured rubber.The distinct mechanical properties,including the stress level,hysteresis and residual strain,of the uncured rubber can all be well characterized.The whole tire building process(including component winding,rubber bladder inflation,component stitching and carcass band folding-back)and the shaping process are simulated using this constitutive model.The simulated green tire profile is in good agreement with the actual profile obtained through 3D scanning.The deformation and stress of the rubber components and the cord reinforcements during production can be obtained fromthe FE simulation,which is helpful for judging the rationality of the tire construction design.Finally,the influence of the parameter“drum width”is investigated,and the simulated result is found to be consistent with the experimental observations,which verifies the effectiveness of the simulation.The established simulation strategy provides some guiding significance for the improvement of tire design parameters and the elimination of tire production defects.

Simulation Technology of Environmental Impacts by Zero-energy Residential Buildings Based on Emergy Analysis Method

This paper presents a simulation technology of environmental impact for the building. By emergy analysis method,emergy costs of building( or construction engineering) can be calculated in the life cycle. It includes the engineering cost, environmental cost and social cost of building. Through integrating GIS technology with multi-agent technology,life cycle substance and energy metabolism of building( construction engineering) can be simulated and their environmental influence can be dynamically displayed. Based on the case study of entries works‘Sunny Inside'by Xiamen University in 2013 China International Solar Decathlon Competition,we discovered the changing pattern of surrounding environmental impact from waste streams of the zero-energy building and ordinary construction. The simulation results verified and showed the Odum principles of maximum power. This paper provides a new research perspective and integration approach for the environmental impact assessment in building and construction engineering. The result will help decision-making in design and construction engineering scheme.

Research on Dynamic Model's Building of Active Magnetic Suspension Systems

An experimental method is introduced in this paper to build the dynamics of AMSS (the active magnetic suspension system), which doesn’t depend on system’s physical parameters. The rotor can be reliably suspended under the unit feedback control system designed with the primary dynamic model obtained. Online identification in frequency domain is processed to give the precise model. Comparisons show that the experimental method is much closer to the precise model than the theoretic method based on magnetic circuit law. So this experimental method is a good choice to build the primary dynamic model of AMSS.

Advanced Deterioration Diagnosis Model for Building External Wall Tiles

In 1981 Taiwan entered a period of intense construction, meaning that today many buildings are more than 30 years old. Lack of maintenance has led to frequent safety incidents involving external walls. This study focuses on a deterioration diagnostic model for external wall tiles of aged buildings, using both stage 1 and stage 2 diagnostic methods. The visual test results are categorized based on impact on public safety, and renovation strategies are proposed. Stage 1 diagnosis mainly adopted the DER visual inspection deterioration assessment method. For enhance the accuracy, this research adopted the Infrared Thermal Imaging detection method to double confirm the visual inspection results. After producing an external wall tile Condition Indicator (CI). For stage 1 diagnostic results that fall in a gray area, stage 2 diagnosis was carried out using a tap tone test, followed by fast Fourier transform and pattern recognition to analyze the tapping results. Finally, the study provides a deterioration evaluation criteria for external wall tiles replacement recommendations and a standard operating procedure for deterioration diagnosis. The study also recommends directions for future amendment of regulations, and provides a basis of reference for the government in determining urban renewal, renovation and maintenance strategies.

Study of Longitudinal Oscillations of a Building on the Basis of Continuum Plate Model

Continuum plate model in the form of a cantilever anisotropic plate developed in the framework of the bimoment theory of plates describing seismic oscillations of buildings is proposed in this paper as a dynamic model of a building. Formulas for the reduced moduli of elasticity, shear and density of the plate model of a building are given. Longitudinal oscillations of a building are studied using the continuum plate and box-like models of the building with Finite Element Model. Numerical results are obtained in the form of graphs, followed by their analysis.

SELECTING CLUSTER MODEL IN Sn - BASED SOLDER ALLOY DESIGN WITH DV - X_α CALCULATION METHOD

Applying calculation method in alloy design should be an important tendency due to its characters of inexpensive cost, high efficiency and prediction. DOS calculations of AuSn, AsSn and SbSn Sn- based alloys have been investigated by employing DV - Xa method, in which different cluster models were adopted to calculate electron structure.It is proved that some regulations must be taken into ac- count in order to carry out alloy design calculation successfully,which are described in this paper in detail.

Evaluation of Quantum Chemical Methods and Basis Sets Applied in the Molecular Modeling of Artemisinin

In this paper, we evaluate semiempirical methods (AM1, PM3, and ZINDO), HF and DFT (B3LYP) in different basis sets to determine which method best describes the sign and magnitude of the geometrical parameters of artemisinin in the region of the endoperoxide ring compared to crystallographic data. We also classify these methods using statistical analysis. The results of PCA were based on three main components, explaining 98.0539% of the total variance, for the geometrical parameters C3O13, O1O2C3, O13C12C12a, and O2C3O13C12. The DFT method (B3LYP) corresponded well with the experimental data in the hierarchical cluster analysis (HCA). The experimental and theoretical angles were analyzed by simple linear regression, and statistical parameters (correlation coefficients, significance, and predictability) were evaluated to determine the accuracy of the calculations. The statistical analysis exhibited a good correlation and high predictive power for the DFT (B3LYP) method in the 6-31G** basis set.

A Three-dimensional Forecasting Model for Oil Spill

A 3-D forecasting model for oil-spill is developed using the finite difference method to numerically solve the shallow water equation. The instantaneous flow distribution in the studied area is calculated and the trajectory of the oil-slick centroid is predicted by means of Lagrange’s method. The computed results agree with the observed data well, this shows that this 3-D forecasting model has high accuracy.

Travel time tomography by ray tracing using the fast sweeping method

This paper presents a gradient-descent travel time tomography method for solving the acoustictype velocity model inversion problem.Similarly to the adjoint-state method,the proposed method is based on the Eikonal equation,enabling simultaneous calculation of contributions from all common-source receivers to the gradient.This overcomes the ineffi ciency inherent in conventional travel time tomography methods,which rely on a two-point ray tracing process.By directly calculating Fréchet derivatives,our method avoids the complex derivation processes associated with the adjoint-state method.The key to calculating the Fréchet derivatives is to calculate a so-called ray-path term.Consequently,compared to the adjoint-state method,the proposed method can explicitly obtain the ray paths,resulting in a more concise and intuitive derivation process.Furthermore,our method retains the benefi ts of the adjoint-state method,such as speed,low memory usage,and robustness.This paper focuses on elucidating the principles and algorithms for calculating the raypath term based on the fast sweeping method.The algorithms could be further speeded up by using parallel computational techniques.Synthetic tests demonstrate that our proposed travel time tomographic method accurately calculates ray paths,regardless of the complexity of the model and recording geometry.

基于DEMATEL-AISM的装配式建筑供应链风险传导关系研究

为了降低装配式建筑供应链风险。本文基于全生命周期从计划、设计、采购、施工装配、生产运输四个主要维度构建装配式建筑供应链风险评价指标体系,运用DEMATEL方法以量化风险因素之间的影响程度,再运用AISM模型分析影响因素的层次结构,最后确定影响装配式建筑供应链风险的根本致因并提出相关对策建议。研究结果以期对装配式建筑供应链各参与主体的管理决策提供参考依据,保障项目实施的顺利进行。

Physical-data Fusion Modeling Method for Energy Consumption Analysis of Smart Building

The energy consumption of buildings accounts for approximately 40%of total energy consumption.An accurate energy consumption analysis of buildings can not only promise significant energy savings but also help estimate the demand response potential more accurately,and consequently brings benefits to the upstream power grid.This paper proposes a novel physical-data fusion modeling(PFM)method for modeling smart buildings that can accurately assess energy consumption.First,a thermal process model of buildings and an electrical load model that focus on building heating,ventilation,and air conditioning(HVAC)systems are presented to analyze the thermal-electrical conversion process of energy consumption of buildings.Second,the PFM method is used to improve the accuracy of the energy consumption analysis model for buildings by modifying the parameters that are difficult to measure in the physical model(i.e.,it effectively modifies the electrical load model based on the proposed PFM method).Finally,case studies involving a real-world dataset recorded in a high-tech park in Changzhou,China,demonstrate that the proposed method exhibits superior performance with respect to the traditional physical modeling(TPM)method and data-driven modeling(DDM)method in terms of the achieved accuracy.

基于熵权法-CIM模型的高速公路施工临近房屋安全风险评价

为了评估高速公路施工对临近房屋的安全影响,基于房屋因素、施工技术与管理因素、房屋周边环境因素,提出了高速公路施工临近房屋安全风险评价指标体系。以某高速公路施工临近10处房屋为研究对象,采用基于熵权法-CIM模型的混合安全风险评价方法,首先计算指标权重;再以其中1处房屋为例,确定其安全风险概率,结果表明:该处房屋安全风险总体较高,基本符合工程施工中的监测结果。

古木建筑榫卯连接M-θ相关曲线模型研究

通过对木结构榫卯连接模型试验及其试验结果分析,得出影响连接刚度的主要因素是替木尺寸,榫头尺寸和卯孔对柱的削弱程度.利用最小二乘法对试验数据进行处理,得出榫头尺寸及卯孔对刚度影响的规律.在原有的3参数幂函数模型的基础上,建立适合木结构榫卯连接的4参数幂函数弯矩-转角的相关曲线模型.本文基本结论可以为古木结构的研究和修缮工作提供一些理论帮助.

几种高层建筑结构简化分析统一的连续-离散化方法

提出几种高层建筑结构简化分析统一的连续-离散化方法,即先将几种高层建筑结构连续化处理以后,均采用等效柱计算模型,再用矩阵位移法分析.几种结构等效柱的单元刚度矩阵具有同一形式,使计算和程序设计简便,用本文的方法可以分析变刚度高层框架、框-剪和剪力墙结构.

风电机组风速-功率特性曲线建模研究综述

风速-功率特性曲线是风力发电机组设计的基础,也是考核机组性能、评估机组发电能力的一项重要指标。介绍风速-功率特性曲线的定义、概念和基本特点,分别从参数方法、非参数方法、离散方法、随机方法 4个方面详细阐述风速-功率特性曲线建模的实现方法。分析建模精度的评价方法,提出目前风速-功率特性曲线建模遇到的问题以及需要进行深入研究的发展方向。

基于Duncan-Chang模型的高层建筑物分层总和法沉降计算与场地变形分析

为研究某新建高层建筑物的沉降变形受场地条件差异及相邻既有建筑物的影响,基于Duncan-Chang模型计算地基沉降分析的方法和分层总和法规范修正公式,对该建筑物的沉降变形进行了对比计算;通过广泛布设沉降监测点,进一步分析了场内建筑物在建设不同阶段的沉降时空规律。结果表明,采用筏板基础的建筑物受荷载及不均匀沉降影响,存在"中间下凹,四周上翘"的挠曲变形特点。同时,在既有建筑物阻挡下,建筑物不同位置的沉降大小受到不同程度"抑制"。随着时间推移,沉降绝对值逐渐减小并在某一时期沉降趋于停止。

框架-剪力墙-薄壁筒斜交结构分析的状态空间法

采用沿高度方向连续化的方法,建立了框架-剪力墙-薄壁筒斜交结构协同分析的连续化计算模型。将沿结构高度方向的坐标模拟成时间坐标,导出了问题的状态空间表达式,用状态空间理论的方法求出了状态向量表达式,由结构的边界条件可求出初始状态向量,从而得到了结构各单元的侧移与内力。给出了数值算例,并与其他算法的结果进行了比较。这种结构计算方法计算量小,精度较高,便于应用,能方便地推广应用于变截面建筑结构。

框架-剪力墙-薄壁筒斜交结构自由振动分析的状态空间法

采用沿高度方向连续化的方法,建立了框架-剪力墙-薄壁筒斜交结构自由振动分析的连续化计算模型。将沿高度方向的坐标虚拟成时间坐标,导出了问题的状态空间表达式,用状态空间理论的方法求出了状态向量表达式,由结构的边界条件可求出初始状态向量,从而得出结构的自振频率。给出了数值算例,并与其他算法的结果进行了比较。

基于AHP-熵权法的装配式建筑安全影响因素研究

为了有效地对装配式建筑的安全水平进行评价,在层次分析法(AHP)及熵权法等理论的基础上,根据现有的分析评价方法,提出AHP与熵权法相结合,对影响装配式建筑安全的相关因素进行整体分析,避免了由于单独运用AHP造成的大量主观因素的误判及熵权法带来的个别因素无法量化的情况。以中建某局的在建装配式项目作为实例,对相关的各项指标,采用AHP-熵权法进行了量化研究,建立了AHP-熵权法的装配式建筑安全评价模型。最终确认了安全事故影响因素的综合权重,并对主要的影响因素提出相应的结论及建议,为装配式建筑安全评价的研究提供了一定的参考。