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期刊论文 39

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关键词

NURBS技术 1

三维视觉知识；三维参数模型；心脏病理诊断；数据增强 1

不确定性 1

不规则三角网 1

卡尔曼滤波；高斯滤波；时间序列估计；贝叶斯滤波；非线性滤波；约束滤波；高斯混合；机动；未知输入 1

参数估计 1

参数变化，参数收益率，多目标优化，切比雪夫仿射，自适应加权和， 1

参数规划 1

可靠性工程 1

失效概率 1

彩色图像灰度化；子空间建模；二阶多项式模型；梯度相关相似；离散搜索 1

成品率预测；参数扰动；多元参数成品率；性能建模；稀疏表示 1

数字地形模型 1

新Bayes估计 1

最小二乘拟合 1

橡胶 1

水利水电工程 1

流变 1

混合整数非线性规划 1

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Implementation of an adaptive feed speed 3D NURBS interpolation algorithm

LIANG Hong-bin, WANG Yong-zhang, LI Xia

《机械工程前沿（英文）》 2006年 第1卷 第4期   页码 403-408 doi: 10.1007/s11465-006-0047-6

摘要： NURBS (non-uniform rational B-spline) interpolation algorithms have been provided in modern CNC (computer numerical control) systems. However, most of them focus on a constant feed speed without considering the contour accuracy. In order to deal with this problem, an adaptive feed speed interpolation algorithm for 3D NURBS parametric curves with confined chord errors is proposed. When the instantaneous radius of the curvature is small enough, the proposed interpolation algorithm automatically reduces the feed speed to meet the specified chord error. In the other situation it uses the second-order Taylor s expansions approximation interpolation algorithm to obtain a constant feed speed so that the contour accuracy in the CNC system is guaranteed. Experimental results were provided to verify the feasibility and precision of the proposed interpolation algorithm.

关键词： NURBS parametric     rational B-spline     second-order     non-uniform rational     precision    

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Parametric equations for notch stress concentration factors of rib–deck welds under bending loading

《结构与土木工程前沿（英文）》 2021年 第15卷 第3期   页码 595-608 doi: 10.1007/s11709-021-0720-1

摘要： The effective notch stress approach for evaluating the fatigue strength of rib–deck welds requires notch stress concentration factors obtained from complex finite element analysis. To improve the efficiency of the approach, the notch stress concentration factors for three typical fatigue-cracking modes (i.e., root–toe, root–deck, and toe–deck cracking modes) were thoroughly investigated in this study. First, we developed a model for investigating the effective notch stress in rib–deck welds. Then, we performed a parametric analysis to investigate the effects of multiple geometric parameters of a rib–deck weld on the notch stress concentration factors. On this basis, the multiple linear stepwise regression analysis was performed to obtain the optimal regression functions for predicting the notch stress concentration factors. Finally, we employed the proposed formulas in a case study. The notch stress concentration factors estimated from the developed formulas show agree well with the finite element analysis results. The results of the case study demonstrate the feasibility and reliability of the proposed formulas. It also shows that the fatigue design curve of FAT225 seems to be conservative for evaluating the fatigue strength of rib–deck welds.

关键词： notch stress concentration factor     rib–deck weld     parametric analysis     regression analysis     parametric equation    

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Building information modeling based on intelligent parametric technology

ZENG Xudong, TAN Jie

《结构与土木工程前沿（英文）》 2007年 第1卷 第3期   页码 367-370 doi: 10.1007/s11709-007-0049-4

摘要： In order to push the information organization process of the building industry, promote sustainable architectural design and enhance the competitiveness of China’s building industry, the author studies building information modeling (BIM) based on intelligent parametric modeling technology. Building information modeling is a new technology in the field of computer aided architectural design, which contains not only geometric data, but also the great amount of engineering data throughout the lifecycle of a building. The author also compares BIM technology with two-dimensional CAD technology, and demonstrates the advantages and characteristics of intelligent parametric modeling technology. Building information modeling, which is based on intelligent parametric modeling technology, will certainly replace traditional computer aided architectural design and become the new driving force to push forward China s building industry in this information age.
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Seismic fragility curves for structures using non-parametric representations

Chu MAI, Katerina KONAKLI, Bruno SUDRET

《结构与土木工程前沿（英文）》 2017年 第11卷 第2期   页码 169-186 doi: 10.1007/s11709-017-0385-y

摘要： Fragility curves are commonly used in civil engineering to assess the vulnerability of structures to earthquakes. The probability of failure associated with a prescribed criterion (e.g., the maximal inter-storey drift of a building exceeding a certain threshold) is represented as a function of the intensity of the earthquake ground motion (e.g., peak ground acceleration or spectral acceleration). The classical approach relies on assuming a lognormal shape of the fragility curves; it is thus parametric. In this paper, we introduce two non-parametric approaches to establish the fragility curves without employing the above assumption, namely binned Monte Carlo simulation and kernel density estimation. As an illustration, we compute the fragility curves for a three-storey steel frame using a large number of synthetic ground motions. The curves obtained with the non-parametric approaches are compared with respective curves based on the lognormal assumption. A similar comparison is presented for a case when a limited number of recorded ground motions is available. It is found that the accuracy of the lognormal curves depends on the ground motion intensity measure, the failure criterion and most importantly, on the employed method for estimating the parameters of the lognormal shape.

关键词： earthquake engineering     fragility curves     lognormal assumption     non-parametric approach     kernel density estimation     epistemic uncertainty    

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水利水电工程三维数字地形建模与分析

钟登华,李明超,王刚,郭享,吴康新

《中国工程科学》 2005年 第7卷 第7期   页码 65-70

摘要： 并根据三维地质建模的特殊需要，引入了NURBS技术对TIN地形模型进行了简化，所获得的NURBS地形模型不仅存储量小，精度损失低，而且易于图形操作运算，便于可视化分析，满足多方面的要求。

关键词： 数字地形模型     不规则三角网     细节层次     NURBS技术     水利水电工程    

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Parametric oscillation of cables and aerodynamic effect

Yong XIA, Jing ZHANG, Youlin XU, Yozo FUJINO,

《结构与土木工程前沿（英文）》 2010年 第4卷 第3期   页码 321-325 doi: 10.1007/s11709-010-0028-z

摘要： This paper addresses the aerodynamic effect on the nonlinear oscillation, particularly parametric vibration of cables in cable-stayed bridges. A simplified 2-DOF model, including a beam and a stayed cable, is formulated first. Response of the cable under global harmonic excitation which is associated with wind speed is obtained using the multiple scales method. Via numerical analysis, the stability condition of the cable in terms of wind speed is derived. The method is applied to a numerical example and a long-span bridge to analyze its all stay cables. It is demonstrated that very large vibration at one of the longest cables in the middle span of the bridge can be parametrically excited when the wind speed is over around 210 km/h (58.5 m/s).

关键词： parametric vibration     cables     cable-stayed bridge     nonlinear vibration    

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Parametric study on seismic performance of self-centering reinforced concrete column with bottom-placed

《结构与土木工程前沿（英文）》   页码 1145-1162 doi: 10.1007/s11709-023-0945-2

摘要： To realize seismic-resilient reinforced concrete (RC) moment-resisting frame structures, a novel self-centering RC column with a rubber layer placed at the bottom (SRRC column) is proposed herein. For the column, the longitudinal reinforcement dissipates seismic energy, the rubber layer allows the rocking of the column, and the unbonded prestressed tendon enables self-centering capacity. A refined finite element model of the SRRC column is developed, the effectiveness of which is validated based on experimental results. Results show that the SRRC column exhibits stable energy dissipation capacity and no strength degradation; additionally, it can significantly reduce permanent residual deformation and mitigate damage to concrete. Extensive parametric studies pertaining to SRRC columns have been conducted to investigate the critical factors affecting their seismic performance.

关键词： seismic resilience     self-centering     rubber layer     flag-shaped hysteresis loop     parametric study    

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不确定条件下采用精确参数规划的非线性模型过程操作

Vassilis M. Charitopoulos,Lazaros G. Papageorgiou,Vivek Dua

《工程（英文）》 2017年 第3卷 第2期   页码 202-213 doi: 10.1016/J.ENG.2017.02.008

摘要：

本文提出了新的两(多) 参数规划(mp-P) 启发算法以求解混合整数非线性规划(MINLP) 问题，并着重说明了算法在过程综合问题中的应用。对于因对数项导致的非线性，开发了针对确定性问题的参数算法(p-MINLP)。关键之处是通过将二进制变量和(或) 不确定参数作为符号参数重新生成和求解一阶Karush Kuhn Tucker(KKT) 系统的解析表达式。为此，采用了符号处理和求解技术。为了证明所提出的算法的适用性和有效性，对两个过程综合案例研究进行了验证，相应的结果经最新的数值MINLP 求解器验证是有效的。对于p-MINLP，给出了不确定参数的显函数表示的最优解。

关键词： 参数规划     不确定性     过程综合     混合整数非线性规划     符号操作    

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Parametric study of hexagonal castellated beams in post-tensioned self-centering steel connections

Hassan ABEDI SARVESTANI

《结构与土木工程前沿（英文）》 2019年 第13卷 第5期   页码 1020-1035 doi: 10.1007/s11709-019-0534-6

摘要： The effects of important parameters (beam reinforcing plates, initial post-tensioning, and material properties of steel angles) on the behavior of hexagonal castellated beams in post-tensioned self-centering (PTSC) connections undergone cyclic loading up to 4% lateral drift have been investigated by finite element (FE) analysis using ABAQUS. The PTSC connection is comprised of bolted top and bottom angles as energy dissipaters and steel strands to provide self-centering capacity. The FE analysis has also been validated against the experimental test. The new formulations derived from analytical method has been proposed to predict bending moment of PTSC connections. The web-post buckling in hexagonal castellated beams has been identified as the dominant failure mode when excessive initial post-tensioning force is applied to reach greater bending moment resistance, so it is required to limit the highest initial post-tensioning force to prevent this failure. Furthermore, properties of steel material has been simulated using bilinear elastoplastic modeling with 1.5% strain-hardening which has perfectly matched with the real material of steel angles. It is recommended to avoid using steel angles with high yielding strength since they lead to the yielding of bolt shank. The necessity of reinforcing plates to prevent beam flange from local buckling has been reaffirmed.

关键词： finite element analysis     hexagonal castellated beam     parametric study     post-tensioned self-centering steel connection     steel moment-resisting frame    

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Parametric control of structural responses using an optimal passive tuned mass damper under stationary

Min-Ho CHEY, Jae-Ung KIM

《结构与土木工程前沿（英文）》 2012年 第6卷 第3期   页码 267-280 doi: 10.1007/s11709-012-0170-x

摘要： In this study, the structural control strategy utilizing a passive tuned mass damper (TMD) system as a seismic damping device is outlined, highlighting the parametric optimization approach for displacement and acceleration control. The theory of stationary random processes and complex frequency response functions are explained and adopted. For the vibration control of an undamped structure, the optimal parameters of a TMD, such as the optimal tuning frequency and optimal damping ratio, to stationary Gaussian white noise acceleration are investigated by using a parametric optimization procedure. For damped structures, a numerical searching technique is used to obtain the optimal parameters of the TMD, and then the explicit formulae for these optimal parameters are derived through a sequence of curve-fitting schemes. Using these specified optimal parameters, several different controlled responses are examined, and then the displacement and acceleration based control effectiveness indices of the TMD are examined from the view point of RMS values. From the viewpoint of the RMS values of displacement and acceleration, the optimal TMDs adopted in this study shows clear performance improvements for the simplified model examined, and this means that the effective optimization of the TMD has a good potential as a customized target response-based structural strategy.

关键词： tuned mass damper     parametric optimization     passive control     white noise     earthquake excitation    

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difference analysis of shallow sprayed concrete tunnels crossing a reverse fault or a normal fault: A parametric

Masoud RANJBARNIA, Milad ZAHERI, Daniel DIAS

《结构与土木工程前沿（英文）》 2020年 第14卷 第4期   页码 998-1011 doi: 10.1007/s11709-020-0621-8

摘要： Urban tunnels crossing faults are always at the risk of severe damages. In this paper, the effects of a reverse and a normal fault movement on a transversely crossing shallow shotcreted tunnel are investigated by 3D finite difference analysis. After verifying the accuracy of the numerical simulation predictions with the centrifuge physical model results, a parametric study is then conducted. That is, the effects of various parameters such as the sprayed concrete thickness, the geo-mechanical properties of soil, the tunnel depth, and the fault plane dip angle are studied on the displacements of the ground surface and the tunnel structure, and on the plastic strains of the soil mass around tunnel. The results of each case of reverse and normal faulting are independently discussed and then compared with each other. It is obtained that deeper tunnels show greater displacements for both types of faulting.

关键词： urban tunnel     sprayed concrete     reverse fault     normal fault     finite difference analysis    

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Predicting lateral displacement caused by seismic liquefaction and performing parametric sensitivity

Nima PIRHADI, Xiaowei TANG, Qing YANG, Afshin ASADI, Hazem Samih MOHAMED

《结构与土木工程前沿（英文）》 2021年 第15卷 第2期   页码 506-519 doi: 10.1007/s11709-021-0677-0

摘要： Lateral displacement due to liquefaction ( ) is the most destructive effect of earthquakes in saturated loose or semi-loose sandy soil. Among all earthquake parameters, the standardized cumulative absolute velocity ( ) exhibits the largest correlation with increasing pore water pressure and liquefaction. Furthermore, the complex effect o fine content( ) at different values has been studied and demonstrated. Nevertheless, these two contexts have not been entered into empirical and semi-empirical models to predict This study bridges this gap by adding to the data set and developing two artificial neural network (ANN) models. The first model is based on the entire range of the parameters, whereas the second model is based on the samples with values that are less than the 28% critical value. The results demonstrate the higher accuracy of the second model that is developed even with less data. Additionally, according to the uncertainties in the geotechnical and earthquake parameters, sensitivity analysis was performed via Monte Carlo simulation (MCS) using the second developed ANN model that exhibited higher accuracy. The results demonstrated the significant influence of the uncertainties of earthquake parameters on predicting

关键词： lateral spreading displacement     cumulative absolute velocity     fine content     artificial neural network     sensitivity analysis     Monte Carlo simulation    

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考虑设计参数扰动的芯片多元参数成品率预测算法 Article

Xin LI,Jin SUN,Fu XIAO

《信息与电子工程前沿（英文）》 2016年 第17卷 第12期   页码 1344-1359 doi: 10.1631/FITEE.1601225

摘要： 随着芯片制造工艺的进步，工艺参数、供电电压及片上温度（Process, voltage, and temperature, PVT）等设计参数扰动已成为芯片设计过程的棘手问题，其所产生的性能指标间相关性将导致芯片参数成品率显著下降。但是，当前芯片参数成品率预测算法主要局限于单一性能指标成品率预测或对多个单性能指标成品率进行均衡优化，而不能同时针对多个性能指标约束进行多元参数成品率预测，易造成参数成品率精度缺失。基于以上问题，本文将多个性能指标同时作为约束条件，提出一种芯片多元参数成品率预测方法。该方法首先考虑PVT参数扰动，利用自适应弹性网（Adaptive elastic net, AEN）对芯片性能指标进行建模。然后，基于乘法定理及马尔科夫链蒙特卡罗法，通过求解累积分布函数（Cumulative distribution function, CDF）对单一性能指标的芯片参数成品率进行预测。最后，同时考虑多个芯片性能指标约束，根据Copula方法准确预测芯片多元参数成品率。实验结果表明，本文方法可以在指定性能指标约束下对芯片多元参数成品率进行有效预测，并可为芯片设计人员提供任意性能指标约束下的多元参数成品率预测曲面。

关键词： 成品率预测；参数扰动；多元参数成品率；性能建模；稀疏表示    

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Effect of variable heat capacities on performance of an irreversible Miller heat engine

Xingmei YE

《能源前沿（英文）》 2012年 第6卷 第3期   页码 280-284 doi: 10.1007/s11708-012-0203-0

摘要： Based on the variable heat capacities of the working fluid, the irreversibility coming from the compression and expansion processes, and the heat leak losses through the cylinder wall, an irreversible cycle model of the Miller heat engine was established, from which expressions for the efficiency and work output of the cycle were derived. The performance characteristic curves of the Miller heat engine were generated through numerical calculation, from which the optimal regions of some main parameters such as the work output, efficiency and pressure ratio were determined. Moreover, the influence of the compression and expansion efficiencies, the variable heat capacities and the heat leak losses on the performance of the cycle was discussed in detail, and consequently, some significant results were obtained.

关键词： Miller cycle     variable heat capacity     irreversibility     parametric optimization    

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Compressive strength prediction and optimization design of sustainable concrete based on squirrel search algorithm-extreme gradient boosting technique

《结构与土木工程前沿（英文）》   页码 1310-1325 doi: 10.1007/s11709-023-0997-3

摘要： Concrete is the most commonly used construction material. However, its production leads to high carbon dioxide (CO2) emissions and energy consumption. Therefore, developing waste-substitutable concrete components is necessary. Improving the sustainability and greenness of concrete is the focus of this research. In this regard, 899 data points were collected from existing studies where cement, slag, fly ash, superplasticizer, coarse aggregate, and fine aggregate were considered potential influential factors. The complex relationship between influential factors and concrete compressive strength makes the prediction and estimation of compressive strength difficult. Instead of the traditional compressive strength test, this study combines five novel metaheuristic algorithms with extreme gradient boosting (XGB) to predict the compressive strength of green concrete based on fly ash and blast furnace slag. The intelligent prediction models were assessed using the root mean square error (RMSE), coefficient of determination (R2), mean absolute error (MAE), and variance accounted for (VAF). The results indicated that the squirrel search algorithm-extreme gradient boosting (SSA-XGB) yielded the best overall prediction performance with R2 values of 0.9930 and 0.9576, VAF values of 99.30 and 95.79, MAE values of 0.52 and 2.50, RMSE of 1.34 and 3.31 for the training and testing sets, respectively. The remaining five prediction methods yield promising results. Therefore, the developed hybrid XGB model can be introduced as an accurate and fast technique for the performance prediction of green concrete. Finally, the developed SSA-XGB considered the effects of all the input factors on the compressive strength. The ability of the model to predict the performance of concrete with unknown proportions can play a significant role in accelerating the development and application of sustainable concrete and furthering a sustainable economy.

关键词： sustainable concrete     fly ash     slay     extreme gradient boosting technique     squirrel search algorithm     parametric analysis    

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标题 作者 时间 类型 操作

Implementation of an adaptive feed speed 3D NURBS interpolation algorithm

LIANG Hong-bin, WANG Yong-zhang, LI Xia

期刊论文

Parametric equations for notch stress concentration factors of rib–deck welds under bending loading

期刊论文

Building information modeling based on intelligent parametric technology

ZENG Xudong, TAN Jie

期刊论文

Seismic fragility curves for structures using non-parametric representations

Chu MAI, Katerina KONAKLI, Bruno SUDRET

期刊论文

水利水电工程三维数字地形建模与分析

钟登华,李明超,王刚,郭享,吴康新

期刊论文

Parametric oscillation of cables and aerodynamic effect

Yong XIA, Jing ZHANG, Youlin XU, Yozo FUJINO,

期刊论文

Parametric study on seismic performance of self-centering reinforced concrete column with bottom-placed

期刊论文

不确定条件下采用精确参数规划的非线性模型过程操作

Vassilis M. Charitopoulos,Lazaros G. Papageorgiou,Vivek Dua

期刊论文

Parametric study of hexagonal castellated beams in post-tensioned self-centering steel connections

Hassan ABEDI SARVESTANI

期刊论文

Parametric control of structural responses using an optimal passive tuned mass damper under stationary

Min-Ho CHEY, Jae-Ung KIM

期刊论文

difference analysis of shallow sprayed concrete tunnels crossing a reverse fault or a normal fault: A parametric

Masoud RANJBARNIA, Milad ZAHERI, Daniel DIAS

期刊论文

Predicting lateral displacement caused by seismic liquefaction and performing parametric sensitivity

Nima PIRHADI, Xiaowei TANG, Qing YANG, Afshin ASADI, Hazem Samih MOHAMED

期刊论文

考虑设计参数扰动的芯片多元参数成品率预测算法

Xin LI,Jin SUN,Fu XIAO

期刊论文

Effect of variable heat capacities on performance of an irreversible Miller heat engine

Xingmei YE

期刊论文

Compressive strength prediction and optimization design of sustainable concrete based on squirrel search algorithm-extreme gradient boosting technique

期刊论文