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基于鲁棒M估计协方差矩阵相位优化的DSInSAR矿区形变监测研究

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中国矿业 2024年第3期33卷 142-151页

作者：曾祥凯孙凤娜陈东兴段文再滕文龙山东省煤田地质局第二勘探队山东济宁272000 阳泉高新技术产业开发区管理委员会山西阳泉045000 中国矿业大学环境与测绘学院江苏徐州221116

针对时序干涉合成孔径雷达(Interferometric Synthetic Aperture Radar,InSAR)技术在矿区所处区域内耕地、裸地等自然地表地物上无法识别有效监测点信息,致使矿区地表形变信息不足及形变解译困难等问题,提出一种基于鲁棒M估计协方差矩... 详细信息

针对时序干涉合成孔径雷达(Interferometric Synthetic Aperture Radar,InSAR)技术在矿区所处区域内耕地、裸地等自然地表地物上无法识别有效监测点信息,致使矿区地表形变信息不足及形变解译困难等问题,提出一种基于鲁棒M估计协方差矩阵特征值分解相位优化的DSInSAR技术,并基于34景Sentinel-1A影像获取了霄云煤矿2022年的地表时序形变。推导基于鲁棒M估计协方差矩阵估计公式,提高对样本异常值及异质像素的鲁棒性,开展基于鲁棒M估计协方差矩阵特征值分解的相位优化处理,分析了上述优化模型与通用相位优化模型的相似性,最终通过对优化估计相位开展相位信息解译处理来获取最终的形变信息。实验结果表明:基于鲁棒M估计协方差矩阵特征值分解相位优化的DSInSAR技术较常规SBAS技术及基于最大似然估计协方差矩阵的DSInSAR技术在监测点密度上分别提高了约11.4倍、0.2倍,且与水准数据对比具有最小的均方根误差,约22 mm;此外,霄云煤矿共包含三个主要形变场,其地表沉降的时序变化呈现出较显著的非线性趋势,煤矿内地表的视线向最大沉降量约418 mm。研究成果为矿区地表形变规律反演及矿区灾害防控提供重要数据支撑。

关键词： DSInSAR技术鲁棒协方差矩阵特征值分解相位优化矿区形变监测

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考虑调节费用补偿的海水抽蓄优化定容策略

电工电能新技术 2024年第4期43卷 63-75页

作者：张彬桥段继儒李咸善李世春万刚三峡大学电气与新能源学院湖北宜昌443002 梯级水电站运行与控制湖北省重点实验室(三峡大学) 湖北宜昌443002 中国长江电力股份有限公司检修厂湖北宜昌443002

通过海上风电与海水抽蓄联合运行参与电网的调峰调度,可有效促进海上风电消纳,助力电网调峰,但需要进行海水抽蓄多目标优化定容研究,解决海水抽蓄成本回收问题以及多目标之间的主观偏好与客观冲突对优化决策的影响等关键问题。为此,本... 详细信息

通过海上风电与海水抽蓄联合运行参与电网的调峰调度,可有效促进海上风电消纳,助力电网调峰,但需要进行海水抽蓄多目标优化定容研究,解决海水抽蓄成本回收问题以及多目标之间的主观偏好与客观冲突对优化决策的影响等关键问题。为此,本文提出了考虑调节费用补偿的海水抽蓄多目标优化定容方法,通过海水抽蓄调节费用双向补偿机制,保障抽蓄调节利益;考虑风电不确定性,计及风蓄联合出力跟踪电网负荷误差最小、海上风电运营效益最大和海水抽蓄收益最大,建立风蓄联合运行多目标优化模型,实现多主体利益共赢。以双向补偿电价、海水抽蓄上水库容量、海水抽蓄机组容量为优化决策变量,通过NSGA-Ⅱ方法优化得到Pareto前沿解集;通过K-means算法对Pareto前沿解集进行聚类作为备选方案;采用层次分析法-熵权法进行主、客观赋权;通过TOPSIS方法将备选方案与理想方案比较排序选出最优解。仿真算例结果验证了本文海水抽蓄优化定容方案能够兼顾新能源消纳效果与多主体利益共赢。

关键词：海水抽水蓄能海上风电 NSGA-Ⅱ算法多目标优化

基于RNA-seq的无量山乌骨鸡(Gallus gallus)肝脏脂代谢相关miRNAs的筛选

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基因组学与应用生物学 2024年第1期43卷 78-90页

作者：施艳燕段俊保欧正淼周杰珑陈粉粉西南林业大学生命科学学院昆明650224

为研究无量山乌骨鸡(Gallus gallus)肝组织脂代谢相关miRNA(microRNA)在不同发育阶段的表达特征,本研究采集出壳当日(D1)和168日龄(D168)母鸡肝组织样品作为试验材料,利用DNBSEQ平台进行测序,采用DEGseq筛选差异表达的miRNA及其靶基因,... 详细信息

为研究无量山乌骨鸡(Gallus gallus)肝组织脂代谢相关miRNA(microRNA)在不同发育阶段的表达特征,本研究采集出壳当日(D1)和168日龄(D168)母鸡肝组织样品作为试验材料,利用DNBSEQ平台进行测序,采用DEGseq筛选差异表达的miRNA及其靶基因,随机选取9个差异表达miRNA进行RT-qPCR验证,KEGG通路分类筛选出脂代谢相关miRNA并进行聚类分析,预测脂代谢相关miRNA靶基因并进行GO和KEGG通路功能富集,构建脂代谢相关miRNA和靶基因关联网络。分析结果表明,筛选出106个差异表达miRNAs,包括54个上调miRNA和52个下调miRNA;聚类得到41个脂代谢相关的miRNAs;预测到38个靶基因,对靶基因的功能注释确定主要富集于甘油磷脂代谢、脂肪酸代谢和鞘脂代谢等脂质代谢相关通路,novel-gga-miR2311-5p-DGKZ、novel-gga-miR2047-3p-ACACA、novel-gga-miR866-3p-DGKH是脂代谢相关候选miRNA-mRNA关系对。研究提示无量山乌骨鸡肝组织miRNA在不同发育阶段的表达特征存在差异,研究结果可为无量山乌骨鸡肝组织miRNA调控脂代谢的分子机制提供参考。

关键词：无量山乌骨鸡肝组织脂代谢 miRNA

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卵巢硬化性间质瘤CT和MRI特征分析

临床放射学杂志 2024年第11期43卷 1923-1928页

作者：段娜李莉崔建民饶敏王洁王志飞王中秋南京中医药大学附属医院放射科南京中医药大学附属医院病理科天津医科大学总医院放射科上海交通大学附属瑞金医院放射科

目的探讨卵巢硬化性间质瘤的CT和MRI表现。方法回顾性分析31例经手术病理证实的卵巢硬化性间质瘤患者的临床资料和14次CT及23次MRI检查数据。结果 31例均为单侧单发，左侧12例(38.7%)、右侧19例(61.3%),肿瘤最大直径3.2～15.0 cm,平均... 详细信息

目的探讨卵巢硬化性间质瘤的CT和MRI表现。方法回顾性分析31例经手术病理证实的卵巢硬化性间质瘤患者的临床资料和14次CT及23次MRI检查数据。结果 31例均为单侧单发，左侧12例(38.7%)、右侧19例(61.3%),肿瘤最大直径3.2～15.0 cm,平均(7.0±2.8)cm。肿瘤包膜光整，类圆形肿块23例(23/31,74.2%),分叶状肿块8例(8/31,25.8%)。实性肿块3例(3/31,9.7%);囊实性肿块28例(28/31,90.3%),其中囊性为主型10例占32.2%,实性为主型18例占58.1%。囊实性肿块表现为厚壁，内壁不规则呈结节、乳头状影，局部“梳齿”样改变23例(23/31,74.2%),瘤内见“湖岛征”27例(27/31,87.1%)。CT检查中2例(2/14,14.3%)瘤内见钙化。增强检查肿瘤呈明显强化22例(22/31,71.0%),肿瘤呈轻中度进行性强化9例(9/31,29.0%),典型呈血管瘤样向心性强化特征，平扫CT到动脉期净增值为(37.6±35.1)hu,平扫CT到静脉期净增值为(52.2±32.4)hu,平扫CT到延迟期净增值为(54.4±34.3)hu。MRI瘤旁见血管蒂及流空血管18例(18/23,78.3%)。病灶实性部分与臀肌的表观扩散系数(ADC)比值为1.18±0.06。结论硬化性间质瘤典型表现为类圆形囊实性肿块，内壁“梳齿”样改变，瘤内见“湖岛征”,类血管瘤样明显渐进性强化。不典型表现为实性肿块和/或轻中度进行性强化。

关键词：卵巢硬化性间质瘤 CT MRI

Automatic Aggregation Enhanced Affinity Propagation Clustering Based on Mutually Exclusive Exemplar Processing

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Computers, Materials & Continua 2023年第10期77卷 983-1008页

作者： Zhihong Ouyang Lei Xue Feng Ding Yongsheng duan Electronic Countermeasure Institute National University of Defense TechnologyHefei230037China

Affinity propagation(AP)is a widely used exemplar-based clustering approach with superior efficiency and clustering ***,a common issue with AP clustering is the presence of excessive exemplars,which limits its ability to perform effective *** research aims to enable AP to automatically aggregate to produce fewer and more compact clusters,without changing the similarity matrix or customizing preference parameters,as done in existing enhanced *** automatic aggregation enhanced affinity propagation(AAEAP)clustering algorithm is proposed,which combines a dependable partitioning clustering approach with AP to achieve this *** partitioning clustering approach generates an additional set of findings with an equivalent number of clusters whenever the clustering stabilizes and the exemplars *** on these findings,mutually exclusive exemplar detection was conducted on the current AP exemplars,and a pair of unsuitable exemplars for coexistence is *** recommendation is then mapped as a novel constraint,designated mutual exclusion and *** address this limitation,a modified AP clustering model is derived and the clustering is restarted,which can result in exemplar number reduction,exemplar selection adjustment,and other data point *** clustering is ultimately completed and a smaller number of clusters are obtained by repeatedly performing automatic detection and clustering until no mutually exclusive exemplars are *** standard classification data sets are adopted for experiments on AAEAP and other clustering algorithms for comparison,and many internal and external clustering evaluation indexes are used to measure the clustering *** findings demonstrate that the AAEAP clustering algorithm demonstrates a substantial automatic aggregation impact while maintaining good clustering quality.

关键词： Clustering affinity propagation automatic aggregation enhanced mutually exclusive exemplars constraint

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一测多评法同时测定小蓟配方颗粒中5种成分

化学分析计量 2024年第5期33卷 36-41页

作者：冯倩仪胡懿何荣荣陈灶树莫秋怡段佳佳刘燎原广东一方制药有限公司广东省中药配方颗粒企业重点实验室广东佛山528244

建立一测多评(QAMS)法同时测定小蓟配方颗粒中新绿原酸、绿原酸、隐绿原酸、咖啡酸、芦丁5种成分的含量。采用高效液相色谱法测定小蓟配方颗粒中5种成分,流动相为乙腈-0.1%磷酸溶液,梯度洗脱,流量为0.8 mL/min,柱温为25℃,检测波长为340... 详细信息

建立一测多评(QAMS)法同时测定小蓟配方颗粒中新绿原酸、绿原酸、隐绿原酸、咖啡酸、芦丁5种成分的含量。采用高效液相色谱法测定小蓟配方颗粒中5种成分,流动相为乙腈-0.1%磷酸溶液,梯度洗脱,流量为0.8 mL/min,柱温为25℃,检测波长为340 nm,进样体积为10μL。5种成分的质量浓度与色谱峰面积线性关系良好,相关系数均为0.999 9,加标平均回收率分别为94.22%、98.58%、100.98%、99.96%、95.23%,测定结果的相对标准偏差均小于1.00%(n=6)。以绿原酸为内参物,建立其与新绿原酸、隐绿原酸、咖啡酸和芦丁的相对校正因子,相对校正因子分别为1.153、1.014、0.783、1.516。将一测多评法计算结果与外标法测定结果进行对比,两种方法对10批小蓟配方颗粒的测定结果均无明显差异,新绿原酸、绿原酸、隐绿原酸、咖啡酸和芦丁测定结果的相对偏差均小于2%。建立的一测多评法测定结果准确可靠,可用于小蓟配方颗粒5种成分的同时测定及质量控制。

关键词：小蓟配方颗粒高效液相色谱法一测多评法相对校正因子

Retrospective and perspective of plant epigenetics in China

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Journal of Genetics and Genomics 2018年第11期45卷 621-638页

作者： Cheng-Guo duan Jian-Kang Zhu Xiaofeng Cao Shanghai Center for Plant Stress Biology and Center of Excellence for Molecular Plant Sciences Chinese Academy of SciencesShanghai 200032，China Department of Horticulture and Landscape Architecture Purdue UniversityWest LafayetteIN 47907USA State Key Laboratory of Plant Genomics and National Center for Plant Gene Research Institute of Genetics and Developmental Biology Chinese Academy of SciencesBeijing 100101China

Epigenetics refers to the study of heritable changes in gene function that do not involve changes in the DNA sequence. Such effects on cellular and physiological phenotypic traits may result from external or environmental factors or be part of normal developmental program. In eukaryotes, DNA wraps on a histone octamer(two copies of H2A, H2B, H3 and H4) to form nucleosome, the fundamental unit of chromatin. The structure of chromatin is subjected to a dynamic regulation through multiple epigenetic mechanisms, including DNA methylation, histone posttranslational modifications(PTMs), chromatin remodeling and noncoding RNAs. As conserved regulatory mechanisms in gene expression, epigenetic mechanisms participate in almost all the important biological processes ranging from basal development to environmental response. Importantly, all of the major epigenetic mechanisms in mammalians also occur in plants. Plant studies have provided numerous important contributions to the epigenetic research. For example, gene imprinting, a mechanism of parental allele-specific gene expression, was firstly observed in maize; evidence of paramutation, an epigenetic phenomenon that one allele acts in a single locus to induce a heritable change in the other allele, was firstly reported in maize and ***, some unique epigenetic mechanisms have been evolved in plants. For example, the 24-nt siRNA-involved RNA-directed DNA methylation(RdDM) pathway is plant-specific because of the involvements of two plant-specific DNA-dependent RNA polymerases, Pol IV and Pol V. A thorough study of epigenetic mechanisms is of great significance to improve crop agronomic traits and environmental adaptability. In this review, we make a brief summary of important progress achieved in plant epigenetics field in China over the past several decades and give a brief outlook on future research *** focus our review on DNA methylation and histone PTMs, the two most important aspects of epigenetic mec

关键词： Plant epigenetics DNA methylation Histone modifications Chromatin remodeling

Convergence Analysis of a Numerical Scheme for the Porous Medium Equation by an Energetic Variational Approach

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Numerical Mathematics(Theory,Methods and Applications) 2020年第1期13卷 63-80页

作者： Chenghua duan Chun Liu Cheng Wang Xingye Yue Department of Mathematics Soochow UniversitySuzhou 215006China Shanghai Center for Mathematical Sciences Fudan UniversityShanghai 200438China Department of Applied Mathematics Illinois Institute of TechnologyChicagoIL 60616USA Department of Mathematics University of MassachusettsDartmouthNorth DartmouthMA 02747-2300USA

The porous medium equation(PME)is a typical nonlinear degenerate parabolic *** have studied numerical methods for PME by an energetic vari-ational approach in[*** et al.,***.,385(2019),pp.13–32],where the trajectory equation can be obtained and two numerical schemes have been devel-oped based on different dissipative energy *** is also proved that the nonlinear scheme,based on f logf as the total energy form of the dissipative law,is uniquely solv-able on an admissible convex set and preserves the corresponding discrete dissipation ***,under certain smoothness assumption,we have also obtained the sec-ond order convergence in space and the first order convergence in time for the *** this paper,we provide a rigorous proof of the error estimate by a careful higher or-der asymptotic expansion and two step error *** latter technique contains a rough estimate to control the highly nonlinear term in a discrete W 1,∞norm and a refined estimate is applied to derive the optimal error order.

关键词： Energetic variational approach porous medium equation trajectory equation optimal rate convergence analysis

质量交换网络传质负荷不可行处理及动态调控策邮

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计算物理 2024年第4期41卷 535-546页

作者：熊思恒段欢欢崔国民肖媛易智康上海理工大学能源与动力工程学院上海市动力工程多相流动与传热重点实验室上海200093 河南牧业经济学院能源与智能工程学院河南郑州450000

本文分析了惩罚函数法处理传质约束对质量交换网络优化带来的消极影响,提出一种传质负荷动态调控策略,采用不同的调控方式处理单元传质约束,即衰减违反传质约束单元的传质负荷或消除单元,以保证结构中的传质单元不违反约束。通过两个质... 详细信息

本文分析了惩罚函数法处理传质约束对质量交换网络优化带来的消极影响,提出一种传质负荷动态调控策略,采用不同的调控方式处理单元传质约束,即衰减违反传质约束单元的传质负荷或消除单元,以保证结构中的传质单元不违反约束。通过两个质量交换网络算例进行验证,所得结果相比文献最优结果分别下降2943$·a^(-1)和1697$·a^(-1),且结构中传质单元数量增加,证明了策略的有效性。

关键词：质量交换网络过程系统集成强制进化随机游走算法不可行解