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Multiscale RBF-based central high resolution schemes for simulation of generalized thermoelasticity problems

Hassan YOUSEFI, Alireza TAGHAVI KANI, Iradj MAHMOUDZADEH KANI

《结构与土木工程前沿(英文)》 2019年 第13卷 第2期   页码 429-455 doi: 10.1007/s11709-018-0483-5

摘要: In this study, average-interpolating radial basis functions (RBFs) are successfully integrated with central high-resolution schemes to achieve a higher-order central method. This proposed method is used for simulation of generalized coupled thermoelasticity problems including shock (singular) waves in their solutions. The thermoelasticity problems include the LS (systems with one relaxation parameter) and GN (systems without energy dissipation) theories with constant and variable coefficients. In the central high resolution formulation, RBFs lead to a reconstruction with the optimum recovery with minimized roughness on each cell: this is essential for oscillation-free reconstructions. To guarantee monotonic reconstructions at cell-edges, the nonlinear scaling limiters are used. Such reconstructions, finally, lead to the total variation bounded (TVB) feature. As RBFs work satisfactory on non-uniform cells/grids, the proposed central scheme can handle adapted cells/grids. To have cost effective and accurate simulations, the multiresolution–based grid adaptation approach is then integrated with the RBF-based central scheme. Effects of condition numbers of RBFs, computational complexity and cost of the proposed scheme are studied. Finally, different 1-D coupled thermoelasticity benchmarks are presented. There, performance of the adaptive RBF-based formulation is compared with that of the adaptive Kurganov-Tadmor (KT) second-order central high-resolution scheme with the total variation diminishing (TVD) property.

关键词: central high resolution schemes     RBFs     higher order accuracy     generalized thermoelasticity     multiresolution-based adaptation    

Higher-order mode effects on the seismic performance of tall piers

Zhongguo GUAN, Jianzhong LI, Yan XU, Hao LU

《结构与土木工程前沿(英文)》 2011年 第5卷 第4期   页码 496-502 doi: 10.1007/s11709-011-0131-9

摘要: A comprehensive analysis was conducted to investigate the seismic performance of a typical tall bridge pier through incremental dynamical analysis (IDA). The effect of higher-order modes was studied specifically. The results showed that higher-order modes significantly contributed to the structural seismic response and should not be neglected. Including these modes resulted in an additional hinge midway up the pier. No plastic hinge would occur at this location for conventional bridge piers. Higher-order modes also led to an out-of-phase response between the hinge rotation at the pier bottom and the displacement at the top. This means that the displacement-based seismic design method cannot correctly predict the mechanical state of the critical hinge and therefore is not suitable for use in the seismic design of tall piers. Mistakenly using the displacement-based seismic design method for tall piers may result in a seriously unsafe condition.

关键词: tall bridges     higher-order mode effects     incremental dynamic analysis    

Iterative HOEO fusion strategy: a promising tool for enhancing bearing fault feature

《机械工程前沿(英文)》 2023年 第18卷 第1期 doi: 10.1007/s11465-022-0725-z

摘要: As parameter independent yet simple techniques, the energy operator (EO) and its variants have received considerable attention in the field of bearing fault feature detection. However, the performances of these improved EO techniques are subjected to the limited number of EOs, and they cannot reflect the non-linearity of the machinery dynamic systems and affect the noise reduction. As a result, the fault-related transients strengthened by these improved EO techniques are still subject to contamination of strong noises. To address these issues, this paper presents a novel EO fusion strategy for enhancing the bearing fault feature nonlinearly and effectively. Specifically, the proposed strategy is conducted through the following three steps. First, a multi-dimensional information matrix (MDIM) is constructed by performing the higher order energy operator (HOEO) on the analysis signal iteratively. MDIM is regarded as the fusion source of the proposed strategy with the properties of improving the signal-to-interference ratio and suppressing the noise in the low-frequency region. Second, an enhanced manifold learning algorithm is performed on the normalized MDIM to extract the intrinsic manifolds correlated with the fault-related impulses. Third, the intrinsic manifolds are weighted to recover the fault-related transients. Simulation studies and experimental verifications confirm that the proposed strategy is more effective for enhancing the bearing fault feature than the existing methods, including HOEOs, the weighting HOEO fusion, the fast Kurtogram, and the empirical mode decomposition.

关键词: higher order energy operator     fault diagnosis     manifold learning     rolling element bearing     information fusion    

基于LiNbO3/SiO2/SiC异质结构实现44 GHz超高频声表面波谐振器 Article

周剑, 张定红, 刘炀辉, 卓凤玲, 钱莉荣, 李红浪, 傅永庆, 段辉高

《工程(英文)》 2023年 第20卷 第1期   页码 112-119 doi: 10.1016/j.eng.2022.05.003

摘要:

声表面波(SAW)技术广泛应用于无线通信、传感器、微流体、光子与量子信息通信等领域。然而,受限于制造技术的发展,SAW器件的频率通常在几个吉赫(GHz)以内,严重限制了SAW器件在5G通信、高精度传感、光子与量子控制中的应用。针对上述关键问题,本文提出将极端纳米制造技术与LiNbO3/SiO2/SiC异质结构衬底相结合的策略,成功制备出波长为160 nm的超高频SAW器件,其高阶模态谐振频率高达约44 GHz,获得的机电耦合系数高达15.7%。基于LiNbO3/SiO2/SiC 异质结构衬底的超高频SAW呈现出多种模态,理论仿真分析确定了高阶声波模态的波模态。进行了超高频SAW微质量传感应用研究,其最高质量灵敏度高达33151.9 MHz⋅mm2⋅μg−1,比频率为978 MHz的传统SAW器件质量灵敏度高4000 倍,是传统石英微天平(QCM)器件质量灵敏度的1011倍。

关键词: 超高频     声表面波     高阶声波模态     高灵敏度    

Reliability analysis of kinematic accuracy for the elastic slider-crank mechanism

TUO Yaofei, CHEN Jianjun, ZHANG Chijiang, CHEN Yongqin

《机械工程前沿(英文)》 2007年 第2卷 第2期   页码 214-217 doi: 10.1007/s11465-007-0037-3

摘要: This paper deals with the static and dynamic output kinematic accuracy of a group of elastic slider-crank mechanisms with the same design parameters by taking the bar length, the joint-gaps, the mass density, and the sectional and the physical parameters as random variables. According to the principle of linear pile-up of small displacement, the static and dynamic output kinematic errors are synthesized, and the reliability model of the kinematic accuracy of the mechanism is built. Through an example, a study of the influencing factors on the reliability of the output kinematic accuracy of the mechanism is made. The results obtained reveal the following facts: with the increase of the crank s rotating speed, the dynamic elastic deformation of the mechanism becomes the principal factor that greatly affects the reliability of the output kinematic accuracy of the mechanism.

关键词: output kinematic     group     slider-crank     kinematic accuracy     displacement    

表征不同DNA高阶结构的单分子分析方法 Review

刘泳麟, 边天元, 刘岩, 李治民, 裴羽丰, 宋杰

《工程(英文)》 2023年 第24卷 第5期   页码 277-292 doi: 10.1016/j.eng.2022.10.009

摘要:

DNA不仅是生命遗传信息的载体,而且是一种高度可编程和自组装的纳米材料。不同的DNA结构与其生物学和化学功能有关。因此,了解各种DNA结构的物理和化学性质在生物学和纳米化学中具有重要意义。然而,群体分子实验忽略了溶液中DNA结构的异质性。单分子分析方法是观察单个分子的行为和探测自由能态的高异质性的有力工具。本文介绍了单分子检测和操纵等单分子分析方法,并讨论了这些方法如何用于测量单/双链DNA(ss/dsDNA)、DNA高阶结构和DNA纳米结构的分子性质。最后,将DNA纳米技术和单分子分析方法进行结合以了解DNA和其他生物物质、软物质的生物物理特性。

关键词: 单分子分析方法     DNA结构     力学性能     构象转变    

FUNCTIONAL GAIN OF FRUIT NETTED-CRACKING IN AN INTROGRESSION LINE OF TOMATO WITH HIGHER EXPRESSION OF

《农业科学与工程前沿(英文)》 2021年 第8卷 第2期

摘要:

Fruit cracking is a major disorder that affects the integrity of fruit and reduces the commercial value of tomato and other fleshy fruit. Here, we have found a novel fruit ‘netted-cracking’ (FNC) phenotype in tomato introgression line IL4-4 which is present in neither the donor parent (LA0716) nor the receptor parent (M82). An F2 population was generated by crossing IL4-4 with M82 to genetically characterize the FNC gene and this showed that a single dominant gene determined fruit netted-cracking. Further map-based cloning narrowed down the FNC locus to a 230 kb region on chromosome 4. Sequencing and annotation analysis show that FNC(Solyc04 g082540) was the most likely candidate gene. Functional characterization of FNC by overexpressing FNCAC and FNCIL4-4resulted in the fruit netted-cracking phenotype, suggesting that the FNC transcript level results in the functional gain of fruit netted-cracking. These findings were further confirmed by FNC ortholog in netted-cracking pepper and melon, indicating a common regulatory mechanism in different plant species. Furthermore, cytoplasm and nucleus-localized FNC indicates increased expression of genes involved in suberin, lignin, lipid transport and cell wall metabolism. These findings provide novel genetic insights into fruit netted-cracking and offer a way to promote molecular improvement toward cracking resistant cultivars.

 

关键词: fine mapping / fruit netted-cracking / introgression line / transcript level    

High-order phase-field model with the local and second-order max-entropy approximants

Fatemeh AMIRI

《结构与土木工程前沿(英文)》 2019年 第13卷 第2期   页码 406-416 doi: 10.1007/s11709-018-0475-5

摘要: We approximate the fracture surface energy functional based on phase-field method with smooth local maximum entropy (LME) and second-order maximum entropy (SME) approximants. The higher-order continuity of the meshfree methods such as LME and SME approximants allows to directly solve the fourth-order phase-field equations without splitting the fourth-order differential equation into two second-order differential equations. We will first show that the crack surface functional can be captured more accurately in the fourth-order model with smooth approximants such as LME, SME and B-spline. Furthermore, smaller length scale parameter is needed for the fourth-order model to approximate the energy functional. We also study SME approximants and drive the formulations. The proposed meshfree fourth-order phase-field formulation show more stable results for SME compared to LME meshfree methods.

关键词: second-order maximum entropy     local maximum entropy     second- and fourth-order phase-field models     B-spline    

An assemble-to-order production planning with the integration of order scheduling and mixed-model sequencing

Baoxi WANG, Zailin GUAN, Yarong CHEN, Xinyu SHAO, Ming JIN, Chaoyong ZHANG

《机械工程前沿(英文)》 2013年 第8卷 第2期   页码 137-145 doi: 10.1007/s11465-013-0251-0

摘要:

For assemble-to-order enterprises, both order scheduling and mixed-model sequencing need to be taken into consideration in the formulation of order-oriented assembly plan. First, determining production priority for the received orders, and then conducting assembly sequence to the mixed-model products in each order. Order scheduling is aimed to ensure order delivery with the optimization goal of minimal total overdue time, while product sequencing is aimed to minimize the makespan so as to meet the requirement on completion time of the order. In the end, the paper establishes a mixed integer programming model based on an industrial case, and makes programming calculation with Xpress-MP to accomplish an order-oriented assembly plan conforming to actual production.

关键词: mixed-model assembly line     assemble-to-order     order scheduling     sequencing    

Split-order consolidation optimization for online supermarkets: Process analysis and optimization models

《工程管理前沿(英文)》   页码 499-516 doi: 10.1007/s42524-022-0221-5

摘要: The large-scale online supermarket is a newly emerging online retailing mode which brings great convenience to people. Online supermarkets are characterized by having large amounts of daily orders with potentially multiple items, diverse delivery times, and a high order-split rate. Multiple shipments for one order caused by order splitting result in high cost and disturbance and a large number of discarded consumable packages at online retailers and customers, causing severe damage to the environment. Accordingly, research on split-order consolidation fulfilment is critical for the advancement of the practice and theory in the context of highly complex online retailing. This paper first analyzes the characteristics and the challenges associated with the split-order consolidation problem that online supermarket is confronting and summarizes the new operational process of split-order consolidation fulfilment. Then, a time–space network optimization model is built, and its corresponding solution algorithm is presented to solve the questions of where and when to consolidate the split orders. Finally, the computation results of the numerical experiments are provided to verify the effectiveness of the algorithm, and a sensitivity analysis of the relevant parameters is performed. This work highlights the effect of order consolidation processes and fulfilment methods on the order fulfilment decision-making for online supermarkets. The purpose of this article is to help pave the way for more effective online supermarket management and order implementation.

关键词: online supermarkets     split-order consolidation     time–space network     genetic algorithm    

Comparison between linear and non-linear forms of pseudo-first-order and pseudo-second-order adsorption

Junxiong LIN , Lan WANG ,

《环境科学与工程前沿(英文)》 2009年 第3卷 第3期   页码 320-324 doi: 10.1007/s11783-009-0030-7

摘要: The best-fit equations of linear and non-linear forms of the two widely used kinetic models, namely pseudo-first-order and pseudo-second-order equations, were compared in this study. The experimental kinetics of methylene blue adsorption on activated carbon was used for this research. Both the correlation coefficient () and the normalized standard deviation Δ(%) were employed as error analysis methods to determine the best-fitting equations. The results show that the non-linear forms of pseudo-first-order and pseudo-second-order models were more suitable than the linear forms for fitting the experimental data. The experimental kinetics may have been distorted by linearization of the linear kinetic equations, and thus, the non-linear forms of kinetic equations should be primarily used to obtain the adsorption parameters. In addition, the Δ(%) method for error analysis may be better to determine the best-fitting model in this case.

关键词: adsorption     pseudo-first order     pseudo-second order     kinetic model     linear method     non-linear method    

高等植物叶片色域的理论研究

程晓舫,董金一,范学良,丁金磊

《中国工程科学》 2006年 第8卷 第12期   页码 66-69

摘要:

利用叶绿素和类胡萝卜素的经典吸收光谱以及植物叶片中不含色素的其他物质成分的光谱,分别求得其在CIE1931色品图中的理论坐标,并根据色度学中的加法混色原理确定出高等植物叶色的理论域范围。实验数据与理论相吻合。

关键词: 高等植物     色素     吸收光谱     色度坐标     色域    

工程结构可靠性分析的高阶矩法研究

宫凤强,李夕兵,邓建

《中国工程科学》 2006年 第8卷 第5期   页码 69-73

摘要:

提出了工程结构可靠性分析的高阶矩方法。主要是基于数值逼近原理,以切比雪夫正交函数族{Tk(x)}做基,利用功能函数的高阶矩信息,通过计算功能函数概率密度函数的逼近表达式,然后根据工程结构可靠性的一般表达式来计算结构的失效概率,进行可靠性分析。通过经典分布函数的数值检验和结构构件失效概率的计算结果比较,表明了该方法在理论上的正确性和工程中的实用性。

关键词: 结构可靠性     高阶矩     切比雪夫多项式     失效概率    

A hybrid deep learning model for robust prediction of the dimensional accuracy in precision milling of

《机械工程前沿(英文)》 2022年 第17卷 第3期 doi: 10.1007/s11465-022-0688-0

摘要: The use of artificial intelligence to process sensor data and predict the dimensional accuracy of machined parts is of great interest to the manufacturing community and can facilitate the intelligent production of many key engineering components. In this study, we develop a predictive model of the dimensional accuracy for precision milling of thin-walled structural components. The aim is to classify three typical features of a structural component—squares, slots, and holes—into various categories based on their dimensional errors (i.e., “high precision,” “pass,” and “unqualified”). Two different types of classification schemes have been considered in this study: those that perform feature extraction by using the convolutional neural networks and those based on an explicit feature extraction procedure. The classification accuracy of the popular machine learning methods has been evaluated in comparison with the proposed deep learning model. Based on the experimental data collected during the milling experiments, the proposed model proved to be capable of predicting dimensional accuracy using cutting parameters (i.e., “static features”) and cutting-force data (i.e., “dynamic features”). The average classification accuracy obtained using the proposed deep learning model was 9.55% higher than the best machine learning algorithm considered in this paper. Moreover, the robustness of the hybrid model has been studied by considering the white Gaussian and coherent noises. Hence, the proposed hybrid model provides an efficient way of fusing different sources of process data and can be adopted for prediction of the machining quality in noisy environments.

关键词: precision milling     dimensional accuracy     cutting force     convolutional neural networks     coherent noise    

Numerical simulation of sudden-expansion two-phase flows with two-scale second-order moment particle

ZENG Zhuoxiong, HAN Shoulei, ZHOU Lixing

《能源前沿(英文)》 2007年 第1卷 第2期   页码 202-206 doi: 10.1007/s11708-007-0026-6

摘要: A two-scale second-order moment particle turbulence model is developed, based on the concept of particle large-scale fluctuation due to turbulence and particle small-scale fluctuation due to collision. The model is employed to simulate gas-particle flows in a sudden-expansion chamber. Simulation results are compared with the experimental results and with those obtained by the single-scale second-order moment two-phase turbulence model. It is shown that the two-scale model is with higher calculating accuracy than the single-scale model.

关键词: gas-particle     single-scale second-order     large-scale fluctuation     second-order     sudden-expansion    

标题 作者 时间 类型 操作

Multiscale RBF-based central high resolution schemes for simulation of generalized thermoelasticity problems

Hassan YOUSEFI, Alireza TAGHAVI KANI, Iradj MAHMOUDZADEH KANI

期刊论文

Higher-order mode effects on the seismic performance of tall piers

Zhongguo GUAN, Jianzhong LI, Yan XU, Hao LU

期刊论文

Iterative HOEO fusion strategy: a promising tool for enhancing bearing fault feature

期刊论文

基于LiNbO3/SiO2/SiC异质结构实现44 GHz超高频声表面波谐振器

周剑, 张定红, 刘炀辉, 卓凤玲, 钱莉荣, 李红浪, 傅永庆, 段辉高

期刊论文

Reliability analysis of kinematic accuracy for the elastic slider-crank mechanism

TUO Yaofei, CHEN Jianjun, ZHANG Chijiang, CHEN Yongqin

期刊论文

表征不同DNA高阶结构的单分子分析方法

刘泳麟, 边天元, 刘岩, 李治民, 裴羽丰, 宋杰

期刊论文

FUNCTIONAL GAIN OF FRUIT NETTED-CRACKING IN AN INTROGRESSION LINE OF TOMATO WITH HIGHER EXPRESSION OF

期刊论文

High-order phase-field model with the local and second-order max-entropy approximants

Fatemeh AMIRI

期刊论文

An assemble-to-order production planning with the integration of order scheduling and mixed-model sequencing

Baoxi WANG, Zailin GUAN, Yarong CHEN, Xinyu SHAO, Ming JIN, Chaoyong ZHANG

期刊论文

Split-order consolidation optimization for online supermarkets: Process analysis and optimization models

期刊论文

Comparison between linear and non-linear forms of pseudo-first-order and pseudo-second-order adsorption

Junxiong LIN , Lan WANG ,

期刊论文

高等植物叶片色域的理论研究

程晓舫,董金一,范学良,丁金磊

期刊论文

工程结构可靠性分析的高阶矩法研究

宫凤强,李夕兵,邓建

期刊论文

A hybrid deep learning model for robust prediction of the dimensional accuracy in precision milling of

期刊论文

Numerical simulation of sudden-expansion two-phase flows with two-scale second-order moment particle

ZENG Zhuoxiong, HAN Shoulei, ZHOU Lixing

期刊论文