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Efficient Inverse Method for Structural Identification Considering Modeling and Response Uncertainties

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Chinese Journal of Mechanical Engineering 2022年第5期35卷 150-161页

作者： Lixiong Cao jie liu Cheng Lu Wei Wang State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China

The inverse problem analysis method provides an effective way for the structural parameter ***,uncertainties wildly exist in the practical engineering inverse *** to the coupling of multi-source uncertainties in the measured responses and the modeling parameters,the traditional inverse method under the deterministic framework faces the challenges in solving mechanism and computing *** this paper,an uncertain inverse method based on convex model and dimension reduction decomposition is proposed to realize the interval identification of unknown structural parameters according to the uncertain measured responses and modeling ***,the polygonal convex set model is established to quantify the epistemic uncertainties of modeling ***,a space collocation method based on dimension reduction decomposition is proposed to transform the inverse problem considering multi-source uncertainties into a few interval inverse problems considering response *** transformed interval inverse problem involves the two-layer solving process including interval propagation and optimization *** order to solve the interval inverse problems considering response uncertainty,an efficient interval inverse method based on the high dimensional model representation and affine algorithm is further *** the coupling of the above two strategies,the proposed uncertain inverse method avoids the time-consuming multi-layer nested calculation procedure,and then effectively realizes the uncertainty identification of unknown structural ***,two engineering examples are provided to verify the effectiveness of the proposed uncertain inverse method.

关键词： Inverse problem Uncertainty quantification Dimension reduction decomposition Polygonal convex set Affine algorithm

Effect of the degree of milling on the microstructure and composition of japonica rice

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Grain & Oil Science and Technology 2022年第4期5卷 194-203页

作者： jie liu Yani Wu Huihui Chen Hongzhou An Yu liu jie Xu College of Food Science and Engineering Henan University of TechnologyZhengzhou 450001China Henan International Joint Laboratory of Grain Quality Analyzing and Processing Zhengzhou 450001China COFCO Engineering&Technology(Zhengzhou)Co. Ltd.Zhengzhou 451150China Wilmar(Shanghai)Biotechnology Research&Development Center Co. Ltd.Shanghai 200137China

The effect of the degree of milling(DM)on the distribution of the residual bran layer on the surface of rice grains and subsequent rice quality is essential for rice milling *** study used scanning electron microscopy(SEM)and energy dispersive spectroscopy(EDS)to examine the microstructure of japonica rice grains,the microstructural changes in different bran portions after milling,and the content and distribution changes of the elements and nutrients in rice after milling to identify the components that can quantify bran residue according to *** SEM results revealed that the thickness of the bran layer and the depth of the grooves in different parts of a rice grain varied,while the depth of the grooves differed between *** DM was 12%,aleurone layer(Al)cells embedded in endosperm(En)remained in the dorsal *** was speculated that this was the reason why there was no significant difference in bran degree when the DM estimated via grain weight loss increased from 10%to 14%(P>0.05).The EDS elemental mapping image showed the qualitative distribution of the elements,which was condensed in the bran and uniform in the *** compositional changes revealed that milling caused the loss of rice nutrients,and the loss rate of DM at 0–10%was more serious than that of DM at 10%–14%.Higher DM(>10%)could remove marginal bran from the dorsal ***,the crude protein,ash,crude fat,dietary fiber,vitamin B1(VB1),and vitamin B2(VB2)content did not change significantly(P>0.05),while the magnesium(Mg),kalium(K),and phosphorus(P)levels decreased substantially(P<0.05).The microstructural and compositional changes indicated that the DM estimated via the grain weight loss increased from 2%to 10%,with the bran decreasing *** DM estimated via the grain weight loss increased from 10%to 14%,with minimal changes in the residual bran in the dorsal grooves of the rice grains,while the Mg,P,and K levels presented precise DM indices during the rice

关键词： Degree of milling Loss of grain weight Residual bran Residual constituents

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冷端管径对高压节流型涡流管性能影响分析

低温工程 2024年第1期 65-71,80页

作者：王杰田园陆梅陈长江刘渊中国石化西北油田分公司采油一厂轮台841604 重庆科技大学石油与天然气工程学院重庆401331 中国石化西北油田分公司采油二厂轮台841604

冷端管径(D_(c))是影响涡流管性能的重要因素之一,基于12 MPa的高压节流工况,以CH_(4)为计算工质,建立物理模型,改变D_(c)为36、38、40、42和44 mm。对比发现:随着D_(c)增大,冷端内旋气体温度逐渐下降,制冷效果提升;热端外旋气体温度先... 详细信息

冷端管径(D_(c))是影响涡流管性能的重要因素之一,基于12 MPa的高压节流工况,以CH_(4)为计算工质,建立物理模型,改变D_(c)为36、38、40、42和44 mm。对比发现:随着D_(c)增大,冷端内旋气体温度逐渐下降,制冷效果提升;热端外旋气体温度先增加后下降,D_(c)=40 mm时制热效果最佳。反映出D_(c)与制冷效果呈正相关,但对制热效果存在最佳值。当D_(c)增大时,内旋气体总压下降幅度逐渐平缓,利于节流;在D_(c)≥40 mm时,外旋气体总压下降幅度变大,且变化不规律,节流时有损调节阀使用寿命。另外D_(c)=44 mm时,外旋气体速度变化规律异常。所以根据工况需求,可控制D_(c)尺寸来调节涡流管制冷制热效果。

关键词：涡流管冷端管径制冷制热节流降压流动分析

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饲料标签常见问题及管理建议

中国饲料 2024年第13期 197-200页

作者：张娜王荃单丽燕刘晓露杨洁全国畜牧总站北京100125 中国农业科学院农业质量标准与检测技术研究所国家饲料质量检验检测中心(北京) 北京100081 中国农业科学院饲料研究所北京100081

文章对当前饲料和饲料添加剂产品标签的常见问题进行了系统梳理,从标签标识的管理要求和反面示例两个角度对市场上发现的主要问题进行了阐述和举例,包括产品名称和商品名称、原料组成、功能声称、成分分析保证值、产品使用说明、卫生要... 详细信息

文章对当前饲料和饲料添加剂产品标签的常见问题进行了系统梳理,从标签标识的管理要求和反面示例两个角度对市场上发现的主要问题进行了阐述和举例,包括产品名称和商品名称、原料组成、功能声称、成分分析保证值、产品使用说明、卫生要求、净含量和保质期、生产者、经营者名称和地址以及抗球虫和中药类药物添加标识等,并通过对各类问题产生的原因进行分析和讨论,提出饲料质量安全管理方面相关的建议。

关键词：饲料标签问题分析

KIF4A和RAD51AP1及CDKN3对食道癌的辅助诊断及预后评估价值

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中华预防医学杂志 2024年第5期58卷 665-672页

作者：邱实郭春霞李雷袁剑锋刘杰彭叶叶邱倩中国人民解放军总医院第七医学中心检验科北京100700 开封市妇幼保健院儿童保健科开封475000 珠海贝索生物技术有限公司珠海519070 中国人民解放军中部战区总医院特勤科武汉430070 重庆市公共卫生医疗救治中心博士后科研工作站重庆400036

利用高通量测序数据探讨食道癌(ESCA)组织中的mRNA的表达及其潜在辅助诊断及预后评估价值。通过整合的生物信息学分析方法,收集美国癌症基因组图谱(TCGA)数据库中173例ESCA患者的基因表达谱及临床数据,利用DESeq2、edgeR和limma分析ESC... 详细信息

利用高通量测序数据探讨食道癌(ESCA)组织中的mRNA的表达及其潜在辅助诊断及预后评估价值。通过整合的生物信息学分析方法,收集美国癌症基因组图谱(TCGA)数据库中173例ESCA患者的基因表达谱及临床数据,利用DESeq2、edgeR和limma分析ESCA组织与癌旁组织样本中的mRNA表达水平的差异,筛选差异表达基因(DEGs);绘制DEGs相关蛋白网络图,对其进行GO和KEGG功能富集分析并筛选枢纽基因,随后对枢纽基因行生存分析,选出与ESCA预后相关的基因并分析其在ESCA中的预后价值;最后绘制受试者工作特征曲线以评价其对ESCA的诊断价值。结果显示,共筛选出在ESCA与癌旁组织之间有显著差异表达的上调DEGs 620个,下调DEGs 668个。DEGs主要参与受体、泛素连接酶等复合物的形成,发挥GTP酶活性、磷脂结合等分子功能,参与调节细胞内物质转运、小分子代谢等生物过程。蛋白功能富集分析显示,这些蛋白主要富集在IL-17信号通路、TNF信号通路、Toll样受体信号通路、EB病毒感染、以及中性粒细胞胞外陷阱形成等通路上,参与ESCA的形成和发展过程。生存分析显示,KIF4A、RAD51AP1和CDKN3高表达的ESCA患者总生存率明显缩短(P均<0.05);同时,KIF4A、RAD51AP1和CDKN3诊断ESCA的曲线下面积分别为0.956、0.951和0.979,灵敏度和特异度均在80%以上;这三者的联合诊断模型ROC结果显示AUC达到0.979,灵敏度和特异度分别为0.914和1;表明KIF4A、RAD51AP1及CDKN3对ESCA具有单独或联合的辅助诊断价值。综上,KIF4A、RAD51AP1及CDKN3对ESCA具有较高的诊断效能,它们的表达升高与ESCA患者的预后可能密切相关,提示这3个基因有可能作为ESCA的辅助诊断和预后评估因子。

关键词：食道癌诊断预后

Test on a buried pipe network subjected to an artificial earthquake produced by multi-millisecond blasting

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Earthquake Engineering and Engineering Vibration 2020年第3期19卷 791-810页

作者： liu Wei Miao Huiquan Wang Chuang Li jie Department of Structural Engineering Tongji UniversityShanghai 200092China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China

Buried pipe networks are important components of lifeline *** experiment is conducted to test a buried pipe network subjected to an artificial earthquake produced by multi-millisecond *** motivation of the research is to verify the feasibility of using multi-millisecond blasting to simulate earthquakes and to validate the deformation relationship between pipe and soil obtained in a single-point explosion *** explosives are used with a time-delay technique to create an extended period of loading on *** dimension of the buried pipe network is 24 m×24 *** artificial earthquake is produced by trinitrotoluene(TNT)*** pipe network consists of ductile cast iron(DCI)pipes,which represent a water distribution network,and welded steel(WS)pipes,which represent a gas supply ***-five kilograms of TNT charges,which are divided into three parts,are detonated by millisecond *** ground motion of the test field,including the accelerations and velocities at different points,and the pipe dynamic responses,including the joint deformations of DCI pipes and the axial strains of WS pipes,are described in ***,the deformation law of buried pipe networks and the deformation relationship between pipe and soil are discussed.

关键词： blasting network buried

心脏磁共振对比增强电影序列对合并微血管阻塞STEMI患者的诊断价值

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磁共振成像 2024年第2期15卷 140-146页

作者：胡莹莹郭勇孙峥赵丽刘志陈楠卢洁首都医科大学宣武医院放射与核医学科北京100053 北京大学国际医院放射科北京102206 首都医科大学宣武医院急诊科北京100053

目的运用磁共振对比增强平衡稳态自由进动(contrast enhancement-steady state free precession,CE-SSFP)电影序列对老年合并微循环阻塞(microvascular obstruction,MVO)的ST段抬高型心肌梗死(ST-segment elevation myocardial infarction,STEMI)患者进行图像质量评价,结合序列参数分析,进一步探讨其对MVO的诊断效能。材料与方法回顾性分析2016年9月至2023年3月50例STEMI患者(STEMI组)的资料,所有患者均进行CE-SSFP电影序列的短轴位、四腔心位、两腔心位扫描。收集与患者组性别、年龄相匹配的50例志愿者为健康对照组。由两名放射诊断医师在CE-SSFP序列上对两组心肌、血池进行定性、定量图像质量评价。采用独立样本t检验分析STEMI组和对照组间的一般资料和影像资料。采用受试者工作特征(receiver operating characteristic,ROC)曲线分析CE-SSFP序列对MVO的诊断效能。结果STEMI组48例患者(96%)和健康对照组49例(98%)的CE-SSFP图像均可满足诊断条件;STEMI组的血池与心肌对比噪声比显著优于健康对照组(222.9±15.6vs.170.1±14.9,t=4.631,P<0.05);CE-SSFP人工识别MVO的敏感度为91.38%,特异度为91.88%,约登指数为0.833;以2倍标准差评价MVO的敏感度为90.23%,特异度为89.94%,约登指数为0.802。两种方法的曲线下面积分别为0.931和0.909。结论CE-SSFP序列可定量评估STEMI合并MVO患者的图像质量,能提供有效量化识别MVO的指标,为临床诊断提供影像学依据。

关键词： ST段抬高型心肌梗死微血管阻塞心脏磁共振对比增强平衡稳态自由进动磁共振成像

Preliminary study of non-isothermal phase change phenomena in vertical Bridgman crystal growth

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Chinese Science Bulletin 2007年第5期52卷 701-710页

作者： liu jie LU WenQiang College of Physical Sciences Graduate University of Chinese Academy of Sciences Beijing 100049 China

Axisymmetric dual reciprocity boundary element method (DRBEM) with augmented items is extended to simulate the heat and mass transfer problems in the vertical Bridgman method (VBM) crystal growth of HgCdTe and CdZnTe. Axial solute concentration redistribution of three regions numerically reap-pears, and the influence of the pulling rate of the ampoule on it is further studied. Secondly, one di-mensional transient phase change phenomena is studied, and non-isothermal phase change phe-nomena is obtained from the initial transient region through the steady growth region to the final tran-sient region. Thirdly, the two-dimensional axisymmetric phase change interface position, interfacial shape and the temperature field of the melt and the crystal are numerically captured under the condi-tion to arrive at the steady state with zero pulling rate of the ampoule. Finally, the study of transient axisymmetric non-isothermal phase change phenomena is stressed and the results are compared with those in isothermal phase change. The influence of the pulling rate on non-isothermal phase change phenomena is revealed.

关键词：法向布里奇曼法晶体生长非等温相变 HgCdTe CdZnTe 半导体材料

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关于液氢储罐安全阀泄放量的计算及校核

中国化工装备 2024年第2期26卷 28-33+40页

作者：刘磊海航赵林南通中集能源装备有限公司

液氢储罐是重要的能源储存过程装备，其安全性至关重要。在液氢储罐设计中，安全阀是保证系统安全运行的重要组成部分之一。由于液氢的临界压力较低，本文旨在通过研究液氢储罐，特别是在超临界状态下安全阀的计算方法，分析其可靠性，... 详细信息

液氢储罐是重要的能源储存过程装备，其安全性至关重要。在液氢储罐设计中，安全阀是保证系统安全运行的重要组成部分之一。由于液氢的临界压力较低，本文旨在通过研究液氢储罐，特别是在超临界状态下安全阀的计算方法，分析其可靠性，确保液氢储罐的安全运行。

关键词：固定式压力容器液氢储罐高真空多层绝热安全阀安全泄放量