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Diving dynamics identification and motion prediction for marine crafts using field data

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Journal of Ocean Engineering and Science 2024年第4期9卷 391-400页

作者： Yiming zhong Caoyang Yu Yulin bai Zheng Zeng Lian Lian School of Oceanography Shanghai Jiao Tong UniversityShanghai 200030China Key Laboratory of Polar Ecosystem and Climate Change Ministry of EducationShanghai Jiao Tong UniversityShanghai 200030China Shanghai Key Laboratory of Polar Life and Environment Sciences Shanghai Jiao Tong UniversityShanghai 200030China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Ensuring accurate parameter identification and diving motion prediction of marine crafts is essential for safe navigation,optimized operational efficiency,and the advancement of marine *** this,this paper proposes an instrumental variable-based least squares(IVLS)***,aiming to balance complexity with accuracy,a decoupled diving model is constructed,incorporating nonlinear actuator characteristics,inertia coefficients,and damping ***,a discrete parameter identification matrix is designed based on this dedicated model,and then a IVLS algorithm is innovatively derived to reject measurement ***,the stability of the proposed algorithm is validated from a probabilistic point of view,providing a solid theoretical ***,performance evaluation is conducted using four depth control datasets obtained from a piston-driven profiling float in Qiandao Lake,with desired depths of 30 m,40 m,50 m,and 60 *** on the diving dynamics identification results,the IVLS algorithm consistently shows superior performance when compared to recursive weighted least squares algorithm and least squares support vector machine algorithm across all depths,as evidenced by lower average absolute error(AVGAE),root mean square error(RMSE),and maximum absolute error values and higher determination coefficient(R2).Specifically,for desired depth of 60 m,the IVLS algorithm achieved an AVGAE of 0.553 m and RMSE of 0.655 m,significantly outperforming LSSVM with AVGAE and RMSE values of 8.782 m and 11.117 m,***,the IVLS algorithm demonstrates a remarkable generalization capability with R2 values consistently above 0.95,indicating its robustness in handling varied diving dynamics.

关键词： Marine craft Parameter identification Motion prediction Instrumental variable-based least-squares algorithm Diving dynamics model

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角度的图像测量法

计量学报 2007年第4期28卷 314-316页

作者：白福忠包晓艳李义军内蒙古工业大学机械学院内蒙古呼和浩特010051

为提高角度测量的精度、速度以及扩大角度测量方法的应用领域,提出一种采用基于计算机视觉的图像测量技术进行角度测量的方法。通过对采集到的被测工件图像进行边缘检测、细化处理和霍夫变换,从而确定出其角度。实验结果表明,角度的图... 详细信息

为提高角度测量的精度、速度以及扩大角度测量方法的应用领域,提出一种采用基于计算机视觉的图像测量技术进行角度测量的方法。通过对采集到的被测工件图像进行边缘检测、细化处理和霍夫变换,从而确定出其角度。实验结果表明,角度的图像测量法在测量精度、速度、抗噪声等方面具有很大的优势。

关键词：计量学角度测量图像测量霍夫变换

Study on the clogging mechanism of punching screen in sand control by the punching structure parameters

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Petroleum Science 2024年第1期21卷 609-620页

作者： fu-Cheng Deng fu-Lin Gui bai-Tao Fan Lei Wen Sheng-Hong Chen Ning Gong Yun-Chen Xiao Zhi-Hui Xu Yangtze University Jingzhou434023HubeiChina CNOOC Research Institute Ltd. Beijing100028China CNOOC Ener Tech-Drilling&Production Co. Tianjin300457China Tianjin Branch of CNOOC Ltd. Tianjin300459China

As an independent sand control unit or a common protective shell of a high-quality screen,the punching screen is the outermost sand retaining unit of the sand control pipe which is used in geothermal well or oil and gas ***,most screens only consider the influence of the internal sand retaining medium parameters in the sand control performance design while ignoring the influence of the plugging of the punching screen on the overall sand retaining performance of the *** explore the clogging mechanism of the punching screen,this paper established the clogging mechanism calculation model of a single punching screen sand control unit by using the computational fluid mechanics-discrete element method(CFD-DEM)combined *** to the combined motion of particles and fluids,the influence of the internal flow state on particle motion and accumulation was *** results showed that(1)the clogging process of the punching sand control unit is divided into three stages:initial clogging,aggravation of clogging and stability of *** the initial stage of blockage,coarse particles form a loose bridge structure,and blockage often occurs preferentially at the streamline gathering place below chamfering inside the sand control *** the stage of blockage intensification,the particle mass develops into a relatively complete sand bridge,which develops from both ends of the opening to the center of the *** the stable plugging stage,the sand deposits show a“fan shape”and form a“V-shaped”gully inside the punching slot element.(2)Under a certain reservoir particle-size distribution,The slit length and opening height have a large influence on the permeability and blockage rate,while the slit width size has little influence on the permeability and blockage *** microscopic clogging mechanism and its law of the punching screen prevention unit are proposed in this study,which has some field guidance significance for the design of punching screen

关键词： Punching screen Plugging CFD-DEM Size parameter Sand control

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数字图像的亚像素位移测量算法改进

煤矿机械 2011年第10期32卷 217-219页

作者：王军白福忠盐城工学院机械工程学院江苏盐城224003 内蒙古工业大学机械学院呼和浩特010062

在基于图像的位移测量中,为了获得较快的测量速度和高的测量精度,提出了基于拉格朗日插值与牛顿法算法的亚像素位移测量方法。该方法首先对5个整像素点的相关系数值作拉格朗日插值,得到一个4次多项式,然后再利用牛顿法去求解此多项式的... 详细信息

在基于图像的位移测量中,为了获得较快的测量速度和高的测量精度,提出了基于拉格朗日插值与牛顿法算法的亚像素位移测量方法。该方法首先对5个整像素点的相关系数值作拉格朗日插值,得到一个4次多项式,然后再利用牛顿法去求解此多项式的极值,该极值点所对应的位置即为待测点的亚像素位移。简捷的拉格朗日插值法与快速收敛牛顿法的综合运用使得位移测量能够在保证良好测量精度的同时有效地减少亚像素匹配中耗时的相关计算。经理论推导与仿真实验证实,在测量精度为0.05~0.1像素的水平下,该测量方法在测量精度、速度等方面具有很大的优势。

关键词：亚像素位移拉格朗日插值牛顿法测量速度测量精度

Improved forecasting via physics-guided machine learning as exemplified using“21·7”extreme rainfall event in Henan

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Science China Earth Sciences 2024年第5期67卷 1652-1674页

作者： Qi zhong Zhicha ZHANG Xiuping YAO Shaoyu HOU Shenming fu Yong CAO Linguo JING China Meteorological Administration Training Center Beijing 100081China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Zhejiang Meteorological Observatory Hangzhou 310017China Hebei Provincial Weather Modification Center Shijiazhuang 050020China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China National Meteorological Center Beijing 100081China School of Computer Science Chengdu University of Information TechnologyChengdu 610225China

As a natural disaster,extreme precipitation is among the most destructive and influential,but predicting its occurrence and evolution accurately is very challenging because of its rarity and *** the example of the“21·7”extreme precipitation event(17–21 July 2021)in Henan Province,this study explores the potential of using physics-guided machine learning to improve the accuracy of forecasting the intensity and location of extreme *** physics-guided ways of embedding physical features,fusing physical model forecasts and revised loss function are used,i.e.,(1)analyzing the anomalous circulation and thermodynamical factors,(2)analyzing the multi-model forecast bias and the associated underlying reasons for it,and(3)using professional forecasting knowledge to design the loss function,and the corresponding results are used as input for machine learning to improve the forecasting *** results indicate that by learning the relationship between anomalous physical features and heavy precipitation,the forecasting of precipitation intensity is improved significantly,but the location is rarely adjusted and more false alarms *** reasons for this are as *** anomalous features used here mainly contain information about large-scale systems and factors which are consistent with the model precipitation deviation;moreover,the samples of extreme precipitation are sparse and so the algorithm used here is ***,by combining“good and different”multi models with machine learning,the advantages of each model are extracted and then the location of the precipitation center in the forecast is improved ***,by combining the appropriate anomalous features with multi-model fusion,an integrated improvement of the forecast of the rainfall intensity and location is ***,this study is a novel exploration to improve the refined forecasting of heavy precipitation with extreme intensity and high variability,

关键词： Extreme precipitation event Refined assessment Anomalous physical features Multi-model fusion Machine learning

The deleterious effects and potential therapeutic strategy of fluorene-9-bisphenol on circadian activity and liver diseases in zebrafish and mice

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Journal of Environmental Sciences 2024年第11期145卷 13-27页

作者： Shuhui Zhang Xiang Zuo Jialu Luan Huijuan bai Zhenhua fu Mingzhu Sun Xin Zhao Xizeng Feng College of Life Science State Key Laboratory of Medicinal Chemical BiologyThe Key Laboratory of Bioactive MaterialsMinistry of EducationNankai UniversityTianjin 300071China Institute of Robotics&Automatic Information System College of Artificial IntelligenceNankai UniversityTianjin 300071China

Increasing evidence indicates that disturbance of the clock genes,which leads to systemic endocrine perturbation,plays a crucial role in the pathogenesis of metabolic and liver ***-9-bisphenol(BHPF)is utilized in the manufacturing of plastic materials but its biological effects on liver homeostasis remain *** impacts and involved mechanisms of BHPF on the liver diseases,metabolism,and circadian clock were comprehensively studied by zebrafish andmouse *** therapeutic effect of melatonin(MT)was also *** and mousemodels with either acute exposure(0.5 and 1μmol/L,1-4 days post-fertilization)or chronic oral exposure(0.5 and 50 mg/(kg·2 days),30 days)were established with various BHPF ***,we identified a crucial role for estrogenic regulation in liver development and circadian locomotor rhythms damaged by BHPF in a zebrafish *** mice showed chaos in circadian activity through the imbalance of circadian clock component Brain and Muscle Aryl hydrocarbon receptor nuclear translocator-like 1 in the liver and *** liver sexual dimorphic alteration alongwith reduced growth hormone and estrogens played a critical role in damaged glucose metabolism,hepatic inflammation,and fibrosis induced by ***,sleep improvement by exogenous MT alleviated BHPF-related glucose metabolism and liver injury in *** proposed the pathogenesis of metabolic and liver disease resulting from BHPF and promising targeted therapy for livermetabolism disorders associated with endocrine perturbation *** results might play a warning role in the administration of endocrine-disrupting chemicals in everyday life and various industry applications.

关键词： Fluorene-9-bisphenol(BHPF) Melatonin Circadian activity Endocrine perturbation Liver diseases Female behavior Hepatic sexual dimorphism

Mechanical Janus lattice with plug-switch orientation

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Theoretical & Applied Mechanics Letters 2024年第1期14卷 23-26页

作者： Yupei Zhang Jiawei zhong Zhengcai Zhao Ruiyu bai Yanqi Yin Yang Yu Bo Li State Key Laboratory for Manufacturing System EngineeringShaanxi Key Laboratory of Intelligent Robots School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China Qian Xuesen Honors College Xi’an Jiaotong UniversityXi’an 710049China

In recent years,materials with asymmetric mechanical response properties(mechanical Janus materials)have been found possess numerous potential applications,*** absorption and vibration *** this study,we propose a novel mechanical Janus lattice whose asymmetric mechanical response can be switched in orientation by a *** finite element analysis and experimental verification,this lattice exhibits asymmetric displacement responses to symmetric ***,with such a plug structure inside,individual lattices can switch the orientation of asymmetry and thus achieve reprogrammable design of a mechanical structure with chained *** reprogrammable asymmetry of this material will offer multiple functions in design of mechanical metamaterials.

关键词： Janus Non-reciprocity Programmability Mechanical metamaterial

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基于图像匹配的无损变形测量

兵器材料科学与工程 2007年第2期30卷 64-66页

作者：王军韩峰白福忠盐城工学院机械工程学院江苏盐城224003 内蒙古工业大学机械学院内蒙古呼和浩特010062

在传统网格法的基础上,给出一种基于图像匹配的无损变形测量新方法。该方法以图像的亚像素匹配为关键技术并采用虚拟网格的思想。在测量时,不用在待测物体表面预制任何标志,而是利用试件表面的数字图像的灰度特征形成虚拟网格,利用区域... 详细信息

在传统网格法的基础上,给出一种基于图像匹配的无损变形测量新方法。该方法以图像的亚像素匹配为关键技术并采用虚拟网格的思想。在测量时,不用在待测物体表面预制任何标志,而是利用试件表面的数字图像的灰度特征形成虚拟网格,利用区域匹配算法完成全场的位移测量;再按照网格法中的应变计算方法得到位移转变成应变。典型拉伸实验证实,该方法与传统网格法的测量结果一致。

关键词：图像匹配亚像素无损变形测量虚拟网格应变测量灰度特征

CFD simulation of pumping ventilation in a three-story isolated building with internal partitioning:Effects of partition widths,heights and locations

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Building Simulation 2024年第2期17卷 267-284页

作者： Huai-Yu zhong Jie Sun Chao Lin Song-Heng Wu Jin Shang Hideki Kikumoto fu-Ping Qian Carlos Jimenez-Bescos fu-Yun Zhao School of Energy and Environment Anhui University of TechnologyMa-An-ShanAnhui Province243002China State Key Laboratory of Green Building in Western China Xi’an University of Architecture&TechnologyXi’anShaanxi ProvinceChina School of Power and Mechanical Engineering Wuhan UniversityWuhanHubei Province430072China Institute of Industrial Science The University of Tokyo4-6-1 KomabaMeguro-kuTokyo153-8505Japan School of Built and Natural Environment University of DerbyDerbyUK

Pumping ventilation(PV),a special single-sided ventilation(SSV),has been certified as an effective strategy to improve the air exchange rate of ***,most studies targeted on the single space,and few studies have been focused on the effect of internal partitioning on *** paper aims to evaluate the ventilation performance of PV influenced by different configurations of internal *** fluid dynamics(CFD)simulation was used to predict the flow fields and ventilation *** width(w/H),height(h/H)and location(d/H)are the three main internal partition parameters considered in this *** simulation results showed that the total,mean and fluctuating ventilation rates all decrease with wider internal *** normalized total ventilation rate decreases by 7.6%when w/H is increased from 50%to 75%.However,the reduction rate is only 0.23%between w/H=0 and 25%,and only 0.61%between w/H=25%and 50%.The ventilation rate is hardly reduced by increasing the partition width when w/H50%.Increasing the partition height will reduce the mean ventilation rate but promote the fluctuating and total ventilation rate in some *** increase of total ventilation rate by 1.4%is observed from h/H=50%to 75%.The ventilation rate is larger when the internal partition is attached to the leeward or windward *** total,mean and fluctuating ventilation rates for d/H=50%are relatively higher than d/H=0 by 1.5%,3.1%and 0.8%,*** the internal partition should be mounted attached to the windward wall so as to obtain the greatest pumping ventilation *** periodicity of pumping flow oscillation and pumping frequency are independent of the partition *** peak power of pumping flow is the lowest for the widest internal partition and is negatively affected by the partition height,but it generally has a positive correlation with the distance between the partition and leeward wa

关键词： pumping ventilation single-sided ventilation internal partitioning periodic oscillation ventilation rate