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Journal of Iron and Steel Research International 2017年第5期24卷 544-555页

作者： Qing Shao Tao Xu tatsuo yoshino Nan Song School of Mechanical Science and Engineering Jilin UniversityChangchun 130022JilinChina

Q345D high-quality low-carbon steel has been extensively employed in structures with stringent weld- ing quality requirements. A multi-objective optimization of welding stress and deformation was presented to design reasonable values of gas metal arc welding parameters and sequences of Q345D T-joints. The optimized factors included continuous variables （welding current （I）, welding voltage （U） ahd welding speed （V）） and discrete variables （welding sequence （S） and welding direc- tion （D））. The concepts of the pointer and stack in Visual Basic （VB） and the interpolation method were introduced to optimize the variables. The optimization objectives included the different combina- tions of the angular distortion and transverse welding stress along the transverse and longitudinal dis- tributions. Based on the design of experiments （DOE） and the polynomial regression （PR） model, the finite element （FE） results of the T-joint were used to establish the mathematical models. The Pareto front and the compromise solutions were obtained by using a multi-objective particle swarm optimization （MOPSO） algorithm. The optimal results were validated by the corresponding results of the FE method, and the error between the FE results and the two-objective results as well as that be-tween the FE results and the three-objective optimization results were less than 17.2% and 21.5%, respectively. The influence and setting regularity of different factors were discussed according to the compromise solutions.

关键词： T-joint Welding parameter Welding sequence Multi-objective optimization Pareto front Gas metal arc welding Q345D

Classified denoising method for laser point cloud data of stored grain bulk surface based on discrete wavelet threshold

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International Journal of Agricultural and Biological Engineering 2016年第4期9卷 123-131页

作者： Shao Qing Xu Tao yoshino tatsuo Song Nan Zhu Hang School of Mechanical Science and Engineering Jilin UniversityChangchun 130022China

Surfaces of stored grain bulk are often reconstructed from organized point sets with noise by 3-D laser scanner in an online measuring *** a result,denoising is an essential procedure in processing point cloud data for more accurate surface reconstruction and grain volume calculation.A classified denoising method was presented in this research for noise removal from point cloud data of the grain bulk *** on the distribution characteristics of cloud point data,the noisy points were divided into three types:The first and second types of the noisy points were either sparse points or small point cloud data deviating and suspending from the main point cloud data,which could be deleted directly by a grid method;the third type of the noisy points was mixed with the main body of point cloud data,which were most difficult to *** point cloud data with those noisy points were projected into a horizontal *** image denoising method,discrete wavelet threshold(DWT)method,was applied to delete the third type of the noisy *** kinds of denoising methods including average filtering method,median filtering method and DWT method were applied respectively and compared for denoising the point cloud *** results show that the proposed method remains the most of the details and obtains the lowest average value of RMSE(Root Mean Square Error,0.219)as well as the lowest relative error of grain volume(0.086%)compared with the other two ***,the proposed denoising method could not only achieve the aim of removing noisy points,but also improve self-adaptive ability according to the characteristics of point cloud data of grain bulk *** results from this research also indicate that the proposed method is effective for denoising noisy points and provides more accurate data for calculating grain volume.

关键词： point cloud data denoising grid method discrete wavelet threshold(DWT)method 3-D laser scanning stored grain

Point cloud simplification algorithm based on particle swarm optimization for online measurement of stored bulk grain

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International Journal of Agricultural and Biological Engineering 2016年第1期9卷 71-78页

作者： Shao Qing Xu Tao yoshino tatsuo Zhao Yujie Yang Wenting Zhu Hang School of Mechanical Science and Engineering Jilin UniversityChangchun 130022China Jilin Academy of Agricultural Machinery Changchun 130022China

The simplification of 3D laser scanning point cloud is an important step of surface reconstruction and volume estimation of bulk grain in *** study presented an adaptive simplification algorithm based on particle swarm optimization(PSO).It introduced PSO into the average distance method,a conventional simplification *** basic idea of this algorithm was to adaptively determine the optimal point reducing intervals of scanning lines according to original point cloud density by *** using the 3D point cloud scanned from bulk grain surface in granary,the proposed algorithm was *** with the average distance method,the proposed algorithm obtained more evenly distributed point set,smaller reduction ratio(6.96%)and higher volume estimation accuracy(relative error was less than 3‰).The 3D laser scanner(GSLS003,Jilin University and SkyViTech Co.,Ltd.,Hangzhou,China)used in this study could scan the complete picture of the grain surface in a granary in one time,so the acquired point cloud data do not have to be *** the good simplification performance and capability of updating the reducing interval at any moment,the proposed algorithm and the 3D laser scanner could be used to realize online real-time measurement of stored bulk grain volume in granary.

关键词： point cloud simplification algorithm particle swarm optimization(PSO) 3D laser scanning large object stored grain

参数化诱导槽设计的吸能盒结构抗撞性多目标优化

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吉林大学学报（工学版） 2013年第1期43卷 39-44页

作者：郝亮徐涛崔健吉野辰萌吉林大学机械科学与工程学院长春130022 吉林大学汽车仿真与控制国家重点实验室长春130022

针对车身前部抗撞部件吸能盒结构的常见的方形截面薄壁锥管,研究了其在低速冲击工况下的最佳抗撞性能模型优化。将压溃力效率及比吸能作为评价指标,建立加权组合形式的多目标优化模型。分析研究分布设置诱导槽对结构吸能与压溃力的影响... 详细信息

针对车身前部抗撞部件吸能盒结构的常见的方形截面薄壁锥管,研究了其在低速冲击工况下的最佳抗撞性能模型优化。将压溃力效率及比吸能作为评价指标,建立加权组合形式的多目标优化模型。分析研究分布设置诱导槽对结构吸能与压溃力的影响,选择诱导槽设定的可行区域。以槽的个数、非均匀分布的槽间距离及槽的深度等作为优化参数,合理选取样本点后,分别应用三次多项式响应面法及径向基法构建其有效代理模型,并采用粒子群法进行优化设计,得出使结构最优的诱导槽位置分布及数量。仿真分析验证了本文方法的有效性。

关键词：车辆工程抗撞性吸能盒诱导槽粒子群优化算法多目标优化

基于三维激光扫描技术的粮食储量监测系统的设计与试验

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农业工程学报 2015年第20期31卷 262-267页

作者：邵晴徐涛吉野辰萌宋男朱航吉林大学机械科学与工程学院长春130025

为实现仓储粮储量在线实时监测,该研究开发了一种基于三维激光扫描技术的粮食储量在线监测系统。采用自主研制的倒置式粮仓专用型三维激光扫描仪对储粮进行扫描,通过上位机通讯、采集点云数据并控制扫描仪的工作过程,应用粮食体积计算... 详细信息

为实现仓储粮储量在线实时监测,该研究开发了一种基于三维激光扫描技术的粮食储量在线监测系统。采用自主研制的倒置式粮仓专用型三维激光扫描仪对储粮进行扫描,通过上位机通讯、采集点云数据并控制扫描仪的工作过程,应用粮食体积计算软件实时计算储粮体积和数量,从而解决了仓储粮储量快速高精度监测的问题。使用该系统在中储粮某直属库进行系统验证试验,结果表明,测量得到的粮食体积满足最大误差不超过1%的技术指标,且经过多次试验检验,系统具有较好的稳定性、测量精度高、操作简便等优点,能够满足仓储粮储量监测的要求。该研究为实现仓储粮储量的快速实时在线监测提供了有效的方法。

关键词：存储监测三维三维激光扫描技术粮食储量点云数据粮食体积计算

基于结构与材料参数的S形薄壁梁抗撞性与轻量化研究

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振动与冲击 2018年第18期37卷 115-120页

作者：樊璐璐吉野辰萌林烨刘欢于征磊吉林大学机械科学与工程学院长春130022

以车身前部吸能部件前纵梁结构中常见方形截面S形薄壁梁为研究对象,探讨了如何通过合理引入诱导槽和加强筋设计提高其抗撞性,及基于材料属性实现轻量化设计。根据诱导槽位置分布、个数和加强筋分布的不同建立8种有限元模型,通过仿真优... 详细信息

以车身前部吸能部件前纵梁结构中常见方形截面S形薄壁梁为研究对象,探讨了如何通过合理引入诱导槽和加强筋设计提高其抗撞性,及基于材料属性实现轻量化设计。根据诱导槽位置分布、个数和加强筋分布的不同建立8种有限元模型,通过仿真优选了两种吸能特性较好的结构模型;在此基础上,以质量为约束,结构几何尺寸为设计变量,提高抗撞性为目标,对其中带有加强筋的S形薄壁梁进行多目标优化,并基于高精度代理模型快速获得了最优设计参数;对比碰撞力-位移仿真曲线与理论曲线,验证了优化模型的有效性;通过将加强筋板的材料改为镁铝合金,进一步实现了轻量化设计。研究成果为实现薄壁梁结构的抗撞性优化与轻量化提供新的解决方案。

关键词：抗撞性轻量化 S形薄壁梁诱导槽加强筋多目标优化

焊接热输入对高速动车组转向架侧梁焊接变形的影响及优化

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焊接学报 2020年第12期41卷 25-32,48,I0002页

作者：邵晴于庆斌尹华徐涛吉野辰萌张天翼中车长春轨道客车股份有限公司长春130062 吉林大学长春130022

转向架构架是高速动车组(electric multiple units,EMU)的重要承载部件,其侧梁的焊接质量直接关系到列车运行的平顺性及安全性.为了研究焊接热输入对转向架侧梁焊接变形的影响,在侧梁结构中提取了曲线T形接头模型,以熔化极气体保护电弧... 详细信息

转向架构架是高速动车组(electric multiple units,EMU)的重要承载部件,其侧梁的焊接质量直接关系到列车运行的平顺性及安全性.为了研究焊接热输入对转向架侧梁焊接变形的影响,在侧梁结构中提取了曲线T形接头模型,以熔化极气体保护电弧焊(gas metal arc welding,GMAW)的焊接速度、焊接电流和焊接电压为研究对象,基于热机耦合仿真分析方法和具有交互作用的正交试验设计(design of experimental,DOE)方法建立代理模型,采用粒子群优化算法(particle swarm optimization,PSO)获得了最优的焊接工艺参数组合.在此基础上,基于极差分析和方差分析(analysis of variance,ANOVA),进一步讨论了上述工艺参数对焊接热输入和焊接残余变形的影响.结果表明,采用最优工艺参数的曲线T形接头模型焊接角变形比采用原生产工艺参数的结果降低了5.04%,采用最优工艺参数的侧梁模型可以保证上下盖板焊接残余变形满足平面度不大于1 mm的要求,无需焊后调平.

关键词：转向架侧梁曲线T形接头粒子群算法焊接热输入焊接残余变形

基于MBNWS算法的假人胸部结构多目标优化设计

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吉林大学学报（工学版） 2018年第4期48卷 1133-1139页

作者：吉野辰萌樊璐璐闫磊徐涛林烨郭桂凯吉林大学机械科学与工程学院长春130022

基于结构材料灵敏度分析,建立了具有粗细网格单元搭配特点且满足试验标定的假人胸部结构有限元简化模型。为了提高该简化模型的"拟人"精度,以同时降低胸部位移峰值及摆锤力峰值与物理假人的误差为目标,建立了基于材料参数的假人胸部多... 详细信息

基于结构材料灵敏度分析,建立了具有粗细网格单元搭配特点且满足试验标定的假人胸部结构有限元简化模型。为了提高该简化模型的"拟人"精度,以同时降低胸部位移峰值及摆锤力峰值与物理假人的误差为目标,建立了基于材料参数的假人胸部多目标优化模型,及其高精度的目标函数代理模型。选取BFGS拟牛顿算法,结合应用加权和技术及Frisch内点罚函数处理,设计了可用于求解不等约束的多目标优化算法,即MBNWS算法。运用该算法获得了假人胸部简化模型多目标优化问题的Pareto最优解集及其前端。结果表明:优化设计后的假人胸部模型可更准确地模拟碰撞中物理假人胸部的力学响应特性。同时,该算法运行速度快、效率高,可推广应用于快速、有效地求解工程中的多目标优化问题。

关键词：机械设计汽车碰撞假人胸部建模多目标优化帕累托最优解加权和法 BFGS算法

How Effective Is Cervical Ripening Using the Controlled-Release Dinoprostone Vaginal Delivery System for Primiparas with Unruptured Membranes?

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Open Journal of Obstetrics and Gynecology 2024年第8期14卷 1185-1196页

作者： yoshino Kinjyo Yukiko Chinen Tadatsugu Kinjo Shuko Chinen Keiko Mekaru Department of Obstetrics and Gynecology Graduate School of Medicine University of the Ryukyus Okinawa Japan

Background: Labor induction has a low success rate, especially in primiparas with unruptured membranes. Previous studies focused on pregnant women with unruptured membranes, but none specifically targeted primiparas. Aims: To compare the effectiveness of a controlled-release dinoprostone vaginal delivery system for cervical dilatation (PROPESS) with that of mechanical dilation for labor induction in primiparous women with unruptured membranes. Materials and Methods: We retrospectively analyzed the data of 90 primiparas with unruptured membranes (41 and 49 in the PROPESS and mechanical dilation groups, respectively). The primary outcome was the cesarean section (CS) rate. The secondary outcomes were the prevalence of vaginal delivery within 12 or 24 h after the initial insertion, oxytocin usage rate, chorioamnionitis, additional use of mechanical dilation in the PROPESS group, and neonatal outcomes. Results: The CS rate was significantly lower in the PROPESS group than in the mechanical dilation group (p = 0.02). A total of 13 patients (31.7%) delivered within 24 h with PROPESS alone, indicating a significantly higher rate of delivery within 24 h in the PROPESS group (p = 0.02). Fewer patients required additional oxytocin in the PROPESS group than in the mechanical dilation group (p = 0.001). However, 14 (34%) patients in the PROPESS group required additional mechanical cervical dilation, resulting in a longer time to delivery than mechanical dilation. Conclusions: PROPESS significantly reduced CS rates and increased delivery rates 24 h after the initial insertion in primiparas with unruptured membranes compared to mechanical dilatation. However, failure to respond to PROPESS resulted in an overall longer delivery time than that of the conventional mechanical dilation group;therefore, identifying predictors of response to PROPESS is necessary.

关键词： PROPESS Labor Induction Primiparas Cervical Ripening Unruptured Membranes

Perinatal Morbidity, Mortality, and Neurodevelopmental Outcomes of Neonates with Fetal Growth Restriction

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Open Journal of Obstetrics and Gynecology 2024年第3期14卷 321-333页

作者： Natsuki Tamashiro Shuko Chinen yoshino Kinjyo Yukiko Chinen Tadatsugu Kinjo Keiko Mekaru Department of Obstetrics and Gynecology Graduate School of Medicine University of the Ryukyus Nishihara Japan

Objective: This study aimed to assess perinatal morbidity, mortality rates, and neurodevelopmental outcomes in the management of fetal growth restriction (FGR) at a single tertiary institute. Methods: Among 2465 deliveries between 2013 and 2019, 109 cases of FGR were reviewed retrospectively for causes, indications for pregnancy termination, perinatal death, overall neonatal outcomes, and long-term prognosis. Results: Excluding FGR due to congenital anomalies (n = 17), the mortality rate was 3.3% (3/92). One neonate delivered at 23 weeks developed cerebral palsy (1.1%). Retinopathy of prematurity occurred in four neonates (4.3%). Neurodevelopmental disorders were present in six neonates (6.5%), all of whom were delivered at 32 - 38 weeks. Significantly lower gestational age at delivery, lower birth weight, and higher umbilical artery resistance indices were observed in neonates with neurodevelopmental disorders. Conclusions: Intact survival before 27 weeks of gestation at delivery with FGR is uncommon. Neurodevelopmental disorders may still develop after delivery at 32 - 38 weeks;consideration should be given to the timing of delivery usingfetal ductus venosus Doppler waveforms measurements to reduce neurodevelopmental disorders.

关键词： Fetal Death Fetal Growth Retardation Neurodevelopmental Disorders Perinatal Mortality Umbilical Artery Doppler Velocimetry