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Journal of Systems Science & Complexity 2022年第4期35卷 1520-1534页

作者： ZHAO Shishun dong lijian SUN Jianguo Center for Applied Statistical Research School of MathematicsJilin UniversityChangchun130012China Department of Statistics University of MissouriColumbiaMO65211USA

This paper discusses regression analysis of interval-censored failure time data arising from the accelerated failure time model in the presence of informative *** the problem,a sieve maximum likelihood estimation approach is proposed and in the method,the copula model is employed to describe the relationship between the failure time of interest and the censoring or observation *** I-spline functions are used to approximate the unknown functions in the model,and a simulation study is carried out to assess the finite sample performance of the proposed approach and suggests that it works well in practical *** addition,an illustrative example is provided.

关键词： Accelerated failure time model copula models informative censoring interval-censored data splines

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Multi-objective genetic algorithms based structural optimization and experimental investigation of the planet carrier in wind turbine gearbox

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Frontiers of Mechanical Engineering 2014年第4期9卷 354-367页

作者： Pengxing YI lijian dong Tielin SHI SchOOs lcienceOfMechaniCan ald TechnoloSy cience and Engineeringwuh an 430074 ChinaHuazh~ng University of

To improve the dynamic performance and reduce the weight of the planet carrier in wind turbine gearbox, a multi-objective optimization method, which is driven by the maximum deformation, the maximum stress and the minimum mass of the studied part, is proposed by combining the response surface method and genetic algorithms in this paper. Firstly, the design points＇ distribution for the design variables of the planet carrier is established with the central composite design （CCD） method. Then, based on the computing results of finite element analysis （FEA）, the response surface analysis is conducted to find out the proper sets of design variable values. And a multi-objective genetic algorithm （MOGA） is applied to determine the direction of optimization. As well, this method is applied to design and optimize the planet carrier in a 1.5 MW wind turbine gearbox, the results of which are validated by an experimental modal test. Compared with the original design, the mass and the stress of the optimized planet carrier are respectively reduced by 9.3% and 40%. Consequently, the cost of planet carrier is greatly reduced and its stability is also improved.

关键词： planet carrier multi-objective optimization,genetic algorithms wind turbine gearbox modal experiment

Superovulation of the Cloned Cattle Derived from Somatic Cells and the Transfer of the Vitrified-Thawed Embryos of the Cloning Cattle

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Agricultural Sciences in China 2004年第12期3卷 937-942页

作者： dongYa-juan BAIXue-jin lijian-dong CHENGMing TheCenterofAnimalEmbryoEngineering LaiyangAgriculturalCollegeLaiyang265200P.R.China

In this experiment, it was designed to carry out superovulation on the two cloned cattles, vitrification and transfer of the embryos recovered from them. First of all, it was carried out vitrification on embryos obtained by IVF. Results showed that there were no significant differences between the blastocysts (obtained by IVF) vitrified in EPS10 and these in EPS20 on the resuscitative rate and the developmental rate. The hatched rate of the blastocysts vitrified in EPS10 (31.3%, 35/112) was significantly higher than that in EPS20 (12.2%, 13/107)(P<0.01), so EPS20 was selected as the vitrification solution to freeze the embryos recovered from the cloned cattle. After superovulation, six (four usable embryos) and ten (nine usable embryos) embryos were respectively recovered from Kangkang and Shuanghuang. Two embryos were selected from the recovered embryos of each cloned cattle to freeze in EPS20, subsequently thawed and transferred into luteal ipsilateral uterine horns of 4 Holstein recipient cows after synchronization of estrus, respectively. At last, one recipient cow (No. 9908) became pregnant and delivered one healthy calf (descendant of the cloned cattle-Shuangshuang). The results of this experi- ment show that the cloned cattle as well as common cattle had better response to the exotic FSH and better ability to multiovulation, the embryos recovered from the cloned cattle can be vitrificated.

关键词： Cloned cattle Superovulation Embryo Vitrification

Analysis of Maize Heterotic Groups and Patterns During Past Decade in China

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Agricultural Sciences in China 2004年第7期3卷 481-489页

作者： TENGWen-tao CAOQing-sheng CHENYan-hui LIUXiang-hui MENShao-dong JINGXi-qiang lijian-sheng ChinaAgriculturalUniversity／NationalMaizeImprovementCenterofChina Beijing100094P.R.China

In this investigation, maize heterotic groups and patterns were analyzed based on theplanting areas from 1992 to 2001 using 84 parent lines of 71 widely extended hybrids andclassification results by SSR markers, in which these lines were assigned into sevenheterotic groups based on Ni-LIs genetic distances. The results indicated that acertain extent change for major heterotic groups of maize took place during past decadein China. The major heterotic groups were Lancaster, Reid, Tang SPT, Zi330 and E28 in theearly 1990s, while they became Reid, Tem-tropicⅠ, Zi330, Tang SPT and Lancaster in theearly 21st century. Tem-tropicⅠwas a new heterotic group, which contained tropic maizegermplasm. The changes for heterotic patterns also occurred. Some new heterotic patternscombining with Tem-tropicⅠappeared, such as ReidTem-tropicⅠ, Zi330Tem-tropicⅠ,Tang SPTTem-tropicⅠ, etc.. Another change was the order of heterotic patterns. In theearly and middle 1990s, the top five heterotic patterns were ReidTang SPT, Zi330Lancaster, LancasterTang SPT, LancasterE28 and ReidZi330, while they became ReidTem-tropicⅠ, ReidZi330, ReidTang SPT, Zi330Tem-tropicⅠand LancasterTang SPT inthe early 21 century. ReidTem-tropicⅠand Zi330Tem-tropicⅠwere laid on the firstand forth Chinese heterotic patterns respectively in 2001. These results providedsignificant information to understand the maize heterotic groups and patterns in Chinaat molecular level.

关键词： Maize Heterotic group Heterotic pattern SSR

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利用谱聚类实现深度图像遮挡边界检测

光学学报 2018年第9期38卷 251-259页

作者：张世辉杨萌董利健燕山大学信息科学与工程学院河北秦皇岛066004 河北省计算机虚拟技术与系统集成重点实验室河北秦皇岛066004

针对视觉目标中存在的遮挡现象,提出一种基于谱聚类实现深度图像遮挡边界检测的方法。首先定义一种新的遮挡相关特征——有效标准差特征,基于相关特征利用均卡方集距抽取部分像素点,构建相似矩阵;然后基于相似矩阵利用Nystrom逼近方法... 详细信息

针对视觉目标中存在的遮挡现象,提出一种基于谱聚类实现深度图像遮挡边界检测的方法。首先定义一种新的遮挡相关特征——有效标准差特征,基于相关特征利用均卡方集距抽取部分像素点,构建相似矩阵;然后基于相似矩阵利用Nystrom逼近方法近似估算全部像素点的拉普拉斯矩阵与逼近特征向量,对得到的逼近特征向量进行聚类分析,把深度图像中的全部像素点划分为遮挡边界点和非遮挡边界点两大类;最后可视化遮挡边界点得到深度图像中的遮挡边界。实验结果表明,本文方法无需标记样本,且在深度图像中目标物体的遮挡边界检测方面具有较好的有效性和普适性。

关键词：机器视觉遮挡边界谱聚类深度图像有效标准差特征均卡方集距

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光刻物镜热像差主动补偿系统设计与实验

光学学报 2017年第3期37卷 295-303页

作者：东立剑崔庆龙李朋志赵磊中国科学院长春光学精密机械与物理研究所吉林长春130033

光刻物镜硅片刻蚀过程中的Z5像散会使光刻物镜波像差产生严重的劣化。为了对像散进行实时补偿,提出一种Z5像散主动补偿系统。该系统由实时数据平台、驱动力系统、柔性支撑结构和光学透镜构成。采用球面干涉仪作为光学透镜表面面形的检... 详细信息

光刻物镜硅片刻蚀过程中的Z5像散会使光刻物镜波像差产生严重的劣化。为了对像散进行实时补偿,提出一种Z5像散主动补偿系统。该系统由实时数据平台、驱动力系统、柔性支撑结构和光学透镜构成。采用球面干涉仪作为光学透镜表面面形的检测设备,利用最小二乘法及线性叠加原理确定驱动参数与面形关系。实验进行了主动补偿系统的驱动器响应函数测试、补偿行程测试、补偿精度测试、补偿分辨率测试。结果表明,系统Z5像散补偿行程达到735nm,Z5像散补偿精度小于2nm,引入的高阶像差小于1nm,像散补偿分辨率为2nm,该系统能够有效补偿光刻物镜系统波前像差,使光刻物镜满足像质要求。

关键词：光学设计光刻物镜热像差主动光学像散响应函数

具有整体径向挠性的光学元件多点均匀支撑结构

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光电工程 2015年第10期42卷 43-48页

作者：赵磊彭海峰于新峰东立剑中国科学院长春光学精密机械与物理研究所应用光学国家重点实验室长春130033

光刻投影物镜中透镜的面形精度是影响光学系统成像质量的关键因素之一。为满足透镜面形精度RMS值优于1~2 nm的指标要求,本文提出了一种具有整体径向挠性的透镜多点均匀支撑结构,基于自重变形和热变形对支撑块尺寸进行了优化设计,分析了... 详细信息

光刻投影物镜中透镜的面形精度是影响光学系统成像质量的关键因素之一。为满足透镜面形精度RMS值优于1~2 nm的指标要求,本文提出了一种具有整体径向挠性的透镜多点均匀支撑结构,基于自重变形和热变形对支撑块尺寸进行了优化设计,分析了透镜在优化后的支撑结构下由自重和热载荷引入的面形变化情况,结果表明：自重引起的透镜上表面面形去除power项后RMS为0.429 nm,下表面面形去除power项后RMS为0.294 nm;热载荷引起的透镜上表面面形RMS为0.409 nm,下表面面形RMS为0.063 nm,能够满足光刻投影物镜中透镜的高精度面形要求。

关键词：光刻投影物镜透镜支撑结构自重变形热变形

哈萨克斯坦某古河道砂岩型铀矿钻孔地浸法采铀工艺技术研究

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中国矿业 2014年第2期23卷 102-106页

作者：陈为义李建东史红霞禹宝利中广核铀业发展有限公司北京100029 中国地质大学北京北京北京100083 核工业243大队内蒙古赤峰024006

地浸采矿因能较好地回收常规开采方法不能回收的低品位矿石,且开采成本低,对环境污染程度小,显示出了广阔的应用前景。笔者总结了多年来一直在哈萨克斯坦从事古河道砂岩型铀矿床酸法钻孔地浸开采的经验,成井工艺、工艺孔修复、添加氧化... 详细信息

地浸采矿因能较好地回收常规开采方法不能回收的低品位矿石,且开采成本低,对环境污染程度小,显示出了广阔的应用前景。笔者总结了多年来一直在哈萨克斯坦从事古河道砂岩型铀矿床酸法钻孔地浸开采的经验,成井工艺、工艺孔修复、添加氧化剂等钻孔地浸工艺技术,认为:采用行列式形式的开采单元,并将部分注液孔设计为抽液孔,可使浸出率提高。采用浓度60%的双氧水(H2O2)作为氧化剂,可以提高溶浸液Fe3+离子浓度,加快四价铀(U4+)转化六价铀(U6+)的速度,提高浸出率,减少硫酸消耗,总体上降低生产成本。

关键词：哈萨克斯坦古河道砂岩型铀矿床钻孔地浸法

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可调支撑力对光学元件面形的影响

激光与光电子学进展 2015年第12期52卷 180-186页

作者：吴志会王东平华洋洋倪明阳东立剑中国科学院长春光学精密机械与物理研究所应用光学国家重点实验室超精密光学工程研究中心吉林长春130033

可调支撑装置是高精度光学元件的常用支撑结构。分析了可调支撑装置支撑力调节对光学元件面形的影响规律。建立可调支撑装置的力学模型,利用有限元法计算光学元件的变形,并对光学元件面形进行Zernike多项式拟合。不同工况下分析结果表明... 详细信息

可调支撑装置是高精度光学元件的常用支撑结构。分析了可调支撑装置支撑力调节对光学元件面形的影响规律。建立可调支撑装置的力学模型,利用有限元法计算光学元件的变形,并对光学元件面形进行Zernike多项式拟合。不同工况下分析结果表明:均匀支撑时光学元件面形均方根(RMS)最小,可调支撑力变化时,引入的光学元件面形RMS以及主要Zernike多项式系数均与支撑力线性相关,与光学元件的初始支撑状态无关。建立Fringe Zernike系数随任意支撑力变化的敏感度矩阵,采用该矩阵预测随机工况下光学元件支撑力调整后面形,预测调节面形与有限元仿真调节面形基本一致,RMS误差优于0.3%,为可调支撑装置的设计与装调提供理论依据。

关键词：光学器件可调支撑结构面形有限元法 Zernike多项式

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原油清防蜡剂、降凝降粘剂的研究

精细与专用化学品 2001年第8期9卷 23-24,10页

作者：张付生谢慧专董丽坚中国石油勘探开发研究院油田化学研究所

研制开发出组成独特、清防蜡效果很好的DQ系列清防蜡剂和结构新颖且降凝、降粘效果很好及抗剪切性能较好的BEM、EAP系列降凝降粘剂。DQ清防蜡剂已在大庆、新疆等油田应用,延长油井热洗周期5倍以上;BEM降凝降粘剂已在鲁宁、中洛等长输管... 详细信息

研制开发出组成独特、清防蜡效果很好的DQ系列清防蜡剂和结构新颖且降凝、降粘效果很好及抗剪切性能较好的BEM、EAP系列降凝降粘剂。DQ清防蜡剂已在大庆、新疆等油田应用,延长油井热洗周期5倍以上;BEM降凝降粘剂已在鲁宁、中洛等长输管线上应用,大幅度降低了原油的凝点、粘度,并取得了可观的经济社会效益。

关键词：原油清防蜡剂降凝降粘剂 DQ系列