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A filtering-based bridge weigh-in-motion system on a continuous multi-girder bridge considering the influence

Hanli WU, Hua ZHAO, Jenny LIU, Zhentao HU

《结构与土木工程前沿（英文）》 2020年 第14卷 第5期   页码 1232-1246 doi: 10.1007/s11709-020-0653-0

摘要： A real-time vehicle monitoring is crucial for effective bridge maintenance and traffic management because overloaded vehicles can cause damage to bridges, and in some extreme cases, it will directly lead to a bridge failure. Bridge weigh-in-motion (BWIM) system as a high performance and cost-effective technology has been extensively used to monitor vehicle speed and weight on highways. However, the dynamic effect and data noise may have an adverse impact on the bridge responses during and immediately following the vehicles pass the bridge. The fast Fourier transform (FFT) method, which can significantly purify the collected structural responses (dynamic strains) received from sensors or transducers, was used in axle counting, detection, and axle weighing technology in this study. To further improve the accuracy of the BWIM system, the field-calibrated influence lines (ILs) of a continuous multi-girder bridge were regarded as a reference to identify the vehicle weight based on the modified Moses algorithm and the least squares method. experimental results indicated that the signals treated with FFT filter were far better than the original ones, the efficiency and the accuracy of axle detection were significantly improved by introducing the FFT method to the BWIM system. Moreover, the lateral load distribution effect on bridges should be considered by using the calculated average ILs of the specific lane individually for vehicle weight calculation of this lane.

关键词： bridge weigh-in-motion     continuous bridge     fast Fourier transform     influence line     axle weight calculation    

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Multiple damage detection in complex bridges based on strain energy extracted from single point measurement

Alireza ARABHA NAJAFABADI, Farhad DANESHJOO, Hamid Reza AHMADI

《结构与土木工程前沿（英文）》 2020年 第14卷 第3期   页码 722-730 doi: 10.1007/s11709-020-0624-5

摘要： Strain Energy of the structure can be changed with the damage at the damage location. The accurate detection of the damage location using this index in a force system is dependent on the degree of accuracy in determining the structure deformation function before and after damage. The use of modal-based methods to identify damage in complex bridges is always associated with problems due to the need to consider the effects of higher modes and the adverse effect of operational conditions on the extraction of structural modal parameters. In this paper, the deformation of the structure was determined by the concept of influence line using the Betti-Maxwell theory. Then two damage detection indicators were developed based on strain energy variations. These indices were presented separately for bending and torsion changes. Finite element analysis of a five-span concrete curved bridge was done to validate the stated methods. Damage was simulated by decreasing stiffness at different sections of the deck. The response regarding displacement of a point on the deck was measured along each span by passing a moving load on the bridge at very low speeds. Indicators of the strain energy extracted from displacement influence line and the strain energy extracted from the rotational displacement influence line (SERIL) were calculated for the studied bridge. The results show that the proposed methods have well identified the location of the damage by significantly reducing the number of sensors required to record the response. Also, the location of symmetric damages is detected with high resolution using SERIL.

关键词： damage detection     strain energy     influence line     complex bridges     rotation displacement    

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Acoustic fault signal extraction via the line-defect phononic crystals

《机械工程前沿（英文）》 2022年 第17卷 第1期   页码 10-10 doi: 10.1007/s11465-021-0666-y

摘要： Rotating machine fault signal extraction becomes increasingly important in practical engineering applications. However, fault signals with low signal-to-noise ratios (SNRs) are difficult to extract, especially at the early stage of fault diagnosis. In this paper, 2D line-defect phononic crystals (PCs) consisting of periodic acrylic tubes with slit are proposed for weak signal detection. The defect band, namely, the formed resonance band of line-defect PCs enables the incident acoustic wave at the resonance frequency to be trapped and enhanced at the resonance cavity. The noise can be filtered by the band gap. As a result, fault signals with high SNRs can be obtained for fault feature extraction. The effectiveness of weak harmonic and periodic impulse signal detection via line-defect PCs are investigated in numerical and experimental studies. All the numerical and experimental results indicate that line-defect PCs can be well used for extracting weak harmonic and periodic impulse signals. This work will provide potential for extracting weak signals in many practical engineering applications.

关键词： phononic crystals     line-defect     fault signal extraction     acoustic enhancement    

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Calculations of narrow-band transimissities and the Planck mean absorption coefficients of real gases using line-by-line

Huaqiang CHU, Mingyan GU, Huaichun ZHOU, Fengshan LIU

《能源前沿（英文）》 2014年 第8卷 第1期   页码 41-48 doi: 10.1007/s11708-013-0292-4

摘要： Narrow-band transmissivities in the spectral range of 150 to 9300 cm and at a uniform resolution of 25 cm were calculated using the statistical narrow-band (SNB) model with the band parameters of Soufiani and Taine, the more recent parameters of André and Vaillon, and the line-by-line (LBL) method along with the HITEMP-2010 spectroscopic database. Calculations of narrow-band transmissivity were conducted for gas columns of different lengths and containing different isothermal and non-isothermal CO -H O-N mixtures at 1 atm. Narrow-band transmissivities calculated by the SNB model are in large relative error at many bands. The more recent SNB model parameters of André and Vaillon are more accurate than the earlier parameters of Soufiani and Taine. The Planck mean absorption coefficients of CO , H O, CO, and CH in the temperature range of 300 to 2500 K were calculated using the LBL method and different versions of the high resolution transmission (HITRAN) and high-temperature spectroscopic absorption parameters (HITEMP) spectroscopic databases. The SNB model was also used to calculate the Planck mean absorption coefficients of these four radiating gases. The LBL results of the Planck mean absorption coefficient were compared with the classical results of Tien and those from the SNB model.

关键词： transimissity     HITEMP     HITRAN     Planck mean absorption coefficients    

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Pareto lexicographic α-robust approach and its application in robust multi objective assembly line balancing

null

《机械工程前沿（英文）》 2014年 第9卷 第3期   页码 257-264 doi: 10.1007/s11465-014-0294-x

摘要：

Robustness in most of the literature is associated with min-max or min-max regret criteria. However, these criteria of robustness are conservative and therefore recently new criteria called, lexicographic α-robust method has been introduced in literature which defines the robust solution as a set of solutions whose quality or jth largest cost is not worse than the best possible jth largest cost in all scenarios. These criteria might be significant for robust optimization of single objective optimization problems. However, in real optimization problems, two or more than two conflicting objectives are desired to optimize concurrently and solution of multi objective optimization problems exists in the form of a set of solutions called Pareto solutions and from these solutions it might be difficult to decide which Pareto solution can satisfy min-max, min-max regret or lexicographic α-robust criteria by considering multiple objectives simultaneously. Therefore, lexicographic α-robust method which is a recently introduced method in literature is extended in the current research for Pareto solutions. The proposed method called Pareto lexicographic α-robust approach can define Pareto lexicographic α-robust solutions from different scenarios by considering multiple objectives simultaneously. A simple example and an application of the proposed method on a simple problem of multi objective optimization of simple assembly line balancing problem with task time uncertainty is presented to get their robust solutions. The presented method can be significant to implement on different multi objective robust optimization problems containing uncertainty.

关键词： Pareto     lexicographic α-robust     assembly line balancing    

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Choosing configurations of transmission line tower grounding by back flashover probability value

Dmitry KUKLIN

《能源前沿（英文）》 2016年 第10卷 第2期   页码 213-226 doi: 10.1007/s11708-016-0398-6

摘要： There is a considerable number of works devoted to electrical characteristics of grounding. These characteristics are important in general. However, in application to grounding of transmission line towers they are not enough to determine what grounding construction is preferable in some particular case, because these characteristics are calculated or measured apart from the grounded object, and only limited number of current (or voltage) source waveforms is used. This paper indicates reasons in favor of the fact that to choose the optimum design of grounding, the calculation model should include the tower as it is. The probability of back flashover, which provides both qualitative and quantitative estimate of the grounding structure efficiency, can be taken as the criterion for the grounding design. The insulation flashover probability is calculated on the basis of engineering method, which evaluates breakdown strength of insulation for nonstandard waveshapes, and probability data on lightning currents. Different approaches are examined for identifying the back flashover probability, as not only amplitudes but also other parameters can be taken into account. Finite-difference time-domain method is used for calculations of transients. It is found that lightning current waveform can greatly influence calculated back flashover probability value.

关键词： grounding     transmission line tower     back flashover probability     FDTD method    

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A fast compound direct iterative algorithm for solving transient line contact elastohydrodynamic lubrication

null

《机械工程前沿（英文）》 2014年 第9卷 第2期   页码 156-167 doi: 10.1007/s11465-014-0297-7

摘要：

A fast compound direct iterative algorithm for solving transient line contact elastohydrodynamic lubrication (EHL) problems is presented. First, by introducing a special matrix splitting iteration method into the traditional compound direct iterative method, the full matrices for the linear systems of equations are transformed into sparse banded ones with any half-bandwidth; then, an extended Thomas method which can solve banded linear systems with any half-bandwidth is derived to accelerate the computing speed. Through the above two steps, the computational complexity of each iteration is reduced approximately from O(N3/3) to O(β2N), where N is the total number of nodes, and β is the half-bandwidth. Two kinds of numerical results of transient EHL line contact problems under sinusoidal excitation or pure normal approach process are obtained. The results demonstrate that the new algorithm increases computing speed several times more than the traditional compound direct iterative method with the same numerical precision. Also the results show that the new algorithm can get the best computing speed and robustness when the ratio, half-bandwidth to total number of nodes, is about 7.5%–10.0% in moderate load cases.

关键词： elastohydrodynamic lubrication     transient     line contact     matrix splitting iteration method     the Thomas method    

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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    

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A novel light fluctuation spectrum method for in-line particle sizing

Shouxuan QIN, Xiaoshu CAI, Li MA

《能源前沿（英文）》 2012年 第6卷 第1期   页码 89-97 doi: 10.1007/s11708-012-0176-z

摘要： This paper discusses two problems in in-line particle sizing when using light fluctuation method. First, by retrieving the ratio of particle concentrations at different time, the intensity of incident light is obtained. There exists narrow error between the calculated and pre-detected value of the intensity of incident light. Secondly, by combining spectrum analysis with Gregory’s theory, a multi-sub-size zone model is proposed, with which the relationship between the distribution of turbidity and the particle size distribution (PSD) can be established, and an algorithm developed to determine the distribution of turbidity. Experiments conducted in the laboratory indicate that the measured size distribution of pulverized coal conforms well with the imaging result.

关键词： in-line measurement     particle size distribution (PSD)     incident light intensity     particle concentration     light fluctuation    

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A naive optimization method for multi-line systems with alternative machines

Weichang KONG, Fei QIAO, Qidi WU

《机械工程前沿（英文）》 2019年 第14卷 第4期   页码 377-392 doi: 10.1007/s11465-019-0544-z

摘要： The scheduling of parallel machines and the optimization of multi-line systems are two hotspots in the field of complex manufacturing systems. When the two problems are considered simultaneously, the resulting problem is much more complex than either of them. Obtaining sufficient training data for conventional data-based optimization approaches is difficult because of the high diversity of system structures. Consequently, optimization of multi-line systems with alternative machines requires a simple mechanism and must be minimally dependent on historical data. To define a general multi-line system with alternative machines, this study introduces the capability vector and matrix and the distribution vector and matrix. A naive optimization method is proposed in accordance with classic feedback control theory, and its key approaches are introduced. When a reasonable target value is provided, the proposed method can realize closed-loop optimization to the selected objective performance. Case studies are performed on a real 5/6-inch semiconductor wafer manufacturing facility and a simulated multi-line system constructed on the basis of the MiniFAB model. Results show that the proposed method can effectively and efficiently optimize various objective performance. The method demonstrates a potential for utilization in multi-objective optimization.

关键词： multi-line systems     alternative machines     feedback control     closed-loop optimization    

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Identifying spreading influence nodes for social networks

《工程管理前沿（英文）》   页码 520-549 doi: 10.1007/s42524-022-0190-8

摘要： The identification of spreading influence nodes in social networks, which studies how to detect important individuals in human society, has attracted increasing attention from physical and computer science, social science and economics communities. The identification algorithms of spreading influence nodes can be used to evaluate the spreading influence, describe the node’s position, and identify interaction centralities. This review summarizes the recent progress about the identification algorithms of spreading influence nodes from the viewpoint of social networks, emphasizing the contributions from physical perspectives and approaches, including the microstructure-based algorithms, community structure-based algorithms, macrostructure-based algorithms, and machine learning-based algorithms. We introduce diffusion models and performance evaluation metrics, and outline future challenges of the identification of spreading influence nodes.

关键词： complex network     network science     spreading influence     machine learning    

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Establishment and drug sensitivity evaluation of murine ascites hepatocarcinoma cell line with high lymphatic

Hongying ZHANG, Jianwu TANG, Wenting ZHU, Chunxiu HU, Guowang XU

《医学前沿（英文）》 2009年 第3卷 第2期   页码 119-129 doi: 10.1007/s11684-009-0022-9

摘要： In order to provide a sensitive cell line model for investigating the mechanisms underlying the lymphatic metastasis of tumors and the effect of medicine against cells, a new murine ascites hepatocarcinoma cell line with high lymphatic metastatic potential (Hca-P/L ) was established and the effect of curcumin on biological behavior of Hca-P/L was observed. Murine ascites hepatocarcinoma cell strain with low lymphatic metastatic potential (Hca-P) was subcutaneously inoculated into the medioventral line of a mouse 615 and the first generation of metastatic tumor cells of inguinal lymph node (Hca-P/L ) was obtained. Then, Hca-P/L was screened by the route of mouse foot pad subcutaneously → lymph node → scale-up culture → mouse foot pad subcutaneously for five times consecutively. The sensitivity of two murine ascites hepatocarcinoma cell lines (Hca-P and Hca-P/L ) and two anchorage-dependent human hepatocarcinoma cell lines (SMC7721 and HepG ) to curcumin were studied by use of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay after these cells had been pretreated by curcumin at the concentration of 15-240 μmol/L for 48 h. After pretreatment by curcumin at the maximum non-cytotoxic dose of 15 μmol/L , the effect of curcumin against cell proliferation of Hca-P and Hca-P/L was observed by inverted microscope, cell growth curve and cell population doubling time; the effects of curcumin on cell cycles of Hca-P/L and Hca-P were studied by flow cytometry (FCM). The results showed Hca-P/L spreading to the lymph nodes at multiple sites in mice was screened from Hca-P. The lymph node metastatic rate was 100%. Curcumin had significant growth inhibiting effect on both murine ascites and human hepatocarcinoma cell lines in a dose-dependent manner ( <0. 05). At concentrations of 30-120 μmol/L, curcumin had more inhibition on murine ascites hepatocarcinoma cell lines than on human anchorage-dependent hepatocarcinoma cell lines. At concentrations of 60-240 μmol/L, curcumin had more inhibition on Hca-P/L with (the 50% inhibitory concentration) IC of 51.48 μmol/L than on Hca-P with IC of 90.87 μmol/L. After pretreatment by curcumin at the maximum non-cytotoxic dose of 15 mol/L for 7 days, the proliferations of Hca-P/L and Hca-P were inhibited ( <0.05) in a time-dependent manner ( <0.01) and the population doubling time of Hca-P/L and Hca-P was prolonged ( <0.01), and curcumin had more inhibition on Hca-P/L than on Hca-P ( <0.05). After pretreatment by 15 μmol/L curcumin for 48 h, the morphous of Hca-P/L was influenced more seriously than that of Hca-P and the cell cycle was redistributed with Hca-P/L being blocked in the S phase and Hca-P in the S and G /M phases. Hca-P/L was validated to be more sensitive to curcumin than Hca-P. Hca-P/L is a novel sensitive cell line model for investigating the mechanisms underlying tumor lymphatic metastasis and the effect of the medicine against cells.

关键词： murine ascites hepatocarcinoma cell line     metastasis     curcumin     drug sensitivity    

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Heterogeneous influence of individuals’ behavior on mask efficacy in gathering environments

《工程管理前沿（英文）》   页码 550-562 doi: 10.1007/s42524-022-0193-5

摘要： Wearing masks is an easy way to operate and popular measure for preventing epidemics. Although masks can slow down the spread of viruses, their efficacy in gathering environments involving heterogeneous person-to-person contacts remains unknown. Therefore, we aim to investigate the epidemic prevention effect of masks in different real-life gathering environments. This study uses four real interpersonal contact datasets to construct four empirical networks to represent four gathering environments. The transmission of COVID-19 is simulated using the Monte Carlo simulation method. The heterogeneity of individuals can cause mask efficacy in a specific gathering environment to be different from the baseline efficacy in general society. Furthermore, the heterogeneity of gathering environments causes the epidemic prevention effect of masks to differ. Wearing masks can greatly reduce the probability of clustered epidemics and the infection scale in primary schools, high schools, and hospitals. However, the use of masks alone in primary schools and hospitals cannot control outbreaks. In high schools with social distancing between classes and in workplaces where the interpersonal contact is relatively sparse, masks can meet the need for prevention. Given the heterogeneity of individual behavior, if individuals who are more active in terms of interpersonal contact are prioritized for mask-wearing, the epidemic prevention effect of masks can be improved. Finally, asymptomatic infection has varying effects on the prevention effect of masks in different environments. The effect can be weakened or eliminated by increasing the usage rate of masks in high schools and workplaces. However, the effect on primary schools and hospitals cannot be weakened. This study contributes to the accurate evaluation of mask efficacy in various gathering environments to provide scientific guidance for epidemic prevention.

关键词： COVID-19     masks     behavioral heterogeneity     asymptomatic infection    

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基于灰色模糊数的公交线网优化研究

邓卫,胡启洲

《中国工程科学》 2007年 第9卷 第11期   页码 21-25

摘要：

在考虑信息不完全的情况下，用灰色模糊数对公交线网优化问题进行了研究。在给出了公交线网优化的约束条件与优化目标的基础上，利用灰色模糊数建立了公交线网优化的决策模型。灰色模糊数是用三参数区间参与优化过程，在允许参数在一定范围内变化的情况下，计算后得到的结果是一个区间向量，其中向量值最大的为所求结果，适用于城市公交线网的优化问题。实例应用分析表明，优化后的公交线网效率提高，可达性良好，可满足城市公交可持续发展的要求。

关键词： 公交线网     优化     灰色模糊数    

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社会影响力分析——模型、方法和评价 Review

李侃, 张林, 黄河燕

《工程（英文）》 2018年 第4卷 第1期   页码 40-46 doi: 10.1016/j.eng.2018.02.004

摘要：

社会影响力分析（SIA）是一个广泛的研究领域，吸引了诸多研究者的兴趣。本文总结了SIA 相关的模型、方法和评价方面代表性的工作，并将SIA 模型归纳为两种类型：微观模型和宏观模型。微观模型考虑人与人之间的相互影响和影响的过程，而宏观模型认为每个人具有相同的传播概率和影响力。本文分析了包括影响最大化、影响最小化、影响流和个人影响力等的社会影响力分析方法；介绍了影响力评价指标，并分析了社会影响力评价模型。本文的目标是对社会影响力提供全面的分析，旨在辅助理解社会行为，为舆论影响提供理论基础，并揭示未来的研究方向和潜在的应用。

关键词： 社会影响力分析     在线社交网络     社会影响力分析模型     影响力评价    

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标题 作者 时间 类型 操作

A filtering-based bridge weigh-in-motion system on a continuous multi-girder bridge considering the influence

Hanli WU, Hua ZHAO, Jenny LIU, Zhentao HU

期刊论文

Multiple damage detection in complex bridges based on strain energy extracted from single point measurement

Alireza ARABHA NAJAFABADI, Farhad DANESHJOO, Hamid Reza AHMADI

期刊论文

Acoustic fault signal extraction via the line-defect phononic crystals

期刊论文

Calculations of narrow-band transimissities and the Planck mean absorption coefficients of real gases using line-by-line

Huaqiang CHU, Mingyan GU, Huaichun ZHOU, Fengshan LIU

期刊论文

Pareto lexicographic α-robust approach and its application in robust multi objective assembly line balancing

null

期刊论文

Choosing configurations of transmission line tower grounding by back flashover probability value

Dmitry KUKLIN

期刊论文

A fast compound direct iterative algorithm for solving transient line contact elastohydrodynamic lubrication

null

期刊论文

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

期刊论文

A novel light fluctuation spectrum method for in-line particle sizing

Shouxuan QIN, Xiaoshu CAI, Li MA

期刊论文

A naive optimization method for multi-line systems with alternative machines

Weichang KONG, Fei QIAO, Qidi WU

期刊论文

Identifying spreading influence nodes for social networks

期刊论文

Establishment and drug sensitivity evaluation of murine ascites hepatocarcinoma cell line with high lymphatic

Hongying ZHANG, Jianwu TANG, Wenting ZHU, Chunxiu HU, Guowang XU

期刊论文

Heterogeneous influence of individuals’ behavior on mask efficacy in gathering environments

期刊论文

基于灰色模糊数的公交线网优化研究

邓卫,胡启洲

期刊论文

社会影响力分析——模型、方法和评价

李侃, 张林, 黄河燕

期刊论文