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On the Gerber-Shiu Discounted Penalty Function for a Surplus Process Described by PDMPs

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Acta Mathematica Sinica,English Series 2010年第5期26卷 951-962页

作者： Jing min he Rong WU College of Science Tianjin University of Technology Tianjin 300384 P. R. China School of Mathematical Sciences Nankai University Tianjin 300071 P. R. China

In this paper, we investigate the Gerber-Shiu discounted penalty function for the surplus process described by a piecewise deterministic Markov process （PDMP）. We derive an integral equation for the Gerber-Shiu discounted penalty function, and obtain the exact solution when the initial surplus is zero. Dickson formulae are also generalized to the present surplus process.

关键词： Gerber-Shiu discounted penalty function piecewise deterministic Markov process ulti- mate ruin probability Volterra integral equation

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电磁探伤三隐藏层BP神经网络成像算法

制造业自动化 2024年第3期46卷 96-100页

作者：李佳恒何敏上海海事大学物流工程学院上海201306

电磁层析成像金属探伤中,迭代算法如Landweber算法因欠定性会影响成像质量,通过灵敏度矩阵迭代会导致成像耗时增加。提出基于三层隐藏层的BP神经网络缺陷成像方法,建立大量样本数据库来训练神经网络,使其在接受检测电压值后能快速生成... 详细信息

电磁层析成像金属探伤中,迭代算法如Landweber算法因欠定性会影响成像质量,通过灵敏度矩阵迭代会导致成像耗时增加。提出基于三层隐藏层的BP神经网络缺陷成像方法,建立大量样本数据库来训练神经网络,使其在接受检测电压值后能快速生成灰度值的缺陷图像。在仿真实验中设置点状、线状等缺陷情况,并使用Landweber算法与BP算法分别创造出6000多种不同缺陷情况的成像结果。仿真实验结果表明,基于BP神经网络的缺陷成像算法与传统迭代算法有本质的区别,适用于金属板的电磁成像探伤,且与Landweber算法相比有更好的成像效果,边缘处理能力更优异,运算速度更快。

关键词：电磁层析成像图像重建 BP神经网络电磁探伤

The constitutions of terpenoids and hormones of leaves in red-flesh citrus mutants and their wild types

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Horticultural Plant Journal 2022年第3期8卷 297-310页

作者： Cuihua Liu min he Juan Xu College of Horticulture Northwest A&F UniversityYangling 712100ShaanxiChina Key Laboratory of Horticultural Plant Biology(ministry of Education) College of Horticulture and ForestryHuazhong Agricultural UniversityWuhan 430070China

To study the profiles and relationships of terpenoids and phytohormones in leaves of red-flesh citrus,we examined four red-flesh mutants that accumulate lycopene in the fruit and their corresponding wild *** compared their contents of monoterpenoid and sesquiterpenoid volatiles,triterpenoid limonoid aglycones,and tetraterpenoid *** types and concentrations of these terpenoids in the leaves varied among genotypes,and the leaf terpenoid profiles differed between red-fleshmutants and theirwild ***,lycopenewas not detected in citrus leaves of all eight varieties,including the *** to phytohormone accumulation in the leaves,the citrus varieties could be classified into a low-phytohormone group(‘Red Anliu’sweet orange,‘Anliu’sweet orange,and‘Cara Cara’navel orange),a high-phytohormone group(‘Seike’navel orange),and a high-jasmonic acid group(‘Red-flesh Guanxi’pummelo,‘Guanxi’pummelo,‘Chuhong’pummelo,and‘Feicui’pummelo).The contents of terpenoid volatiles were very low in leaves of‘Red-flesh Guanxi’and‘Guanxi’pummelo;therefore,they are ideal materials for verifying the functions of genes related to terpenoid volatiles in overexpression *** volatiles were positively correlated with phytohormones of abscisic acid,jasmonic acid,and salicylic *** together,lycopene was undetected in the leaves of redflesh citrus mutants with abundant lycopene in their juice sacs,which suggested a tissue-specific accumulation pattern of lycopene in citrus red-flesh ***,leaf volatile profiles could be suitable to develop fingerprint chromatograms of citrus resources,since leaf volatile profiles were dominated by several compounds that varied among genotypes in their combinations and concentrations.

关键词： Citrus Carotenoid Terpenoid volatile Limonoid aglycone Hormone Leaf

Integration of InSAR and GPS for hydraulic engineering

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Science China(Technological Sciences) 2007年第z1期50卷 111-124页

作者： he XiuFeng LUO HaiBin HUANG QiHuan he min Institute of Satellite Navigation & Spatial Information System Hohai UniversityNanjing 210098China Institute of Satellite Navigation & Spatial Information SystemHohai UniversityNanjing 210098China Institute of Satellite Navigation & Spatial Information SystemHohai UniversityNanjing 210098China Institute of Satellite Navigation & Spatial Information SystemHohai UniversityNanjing 210098China

Interferometric synthetic aperture radar (InSAR) is a potential earth observation approach, and it has been demonstrated to have a variety of applications in measuring ground movement, urban subsidence and landslides. Currently InSAR provides the ability to map accurate DEM and measure ground deformation to sub-centimeter accuracy. However, many factors affect InSAR to measure ground movement since dam constructions are built in a large scale area with a complicated climate and unstable geology. This paper discusses potential applications of integrated InSAR and GPS to monitor a large-scale ground movement due to hydropower developments. The integration of InSAR and GPS can provide a cost-effective means for monitoring deformation of hydropower developments. Moreover, two novel methods, both the improved spatial interpolating method and estimation of 3D surface motion velocities method, are proposed and the experimental results and analysis are given in this paper.

关键词： InSAR GPS hydraulic and hydropower engineering slides monitoring

成人病毒性脑炎血清和脑脊液GFAP、CPK-BB、NSE、S-100B表达及与病情、预后关系研究

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河北医科大学学报 2024年第2期45卷 196-201页

作者：贺婕康妍吴建楠贺敏河北中石油中心医院神经内科河北廊坊065000 河北中石油中心医院精神心理科河北廊坊065000

目的探讨血清和脑脊液胶质纤维酸性蛋白(glial fibrillary acidic protein,GFAP)、肌酸激酶脑型(creatine phosphokinase-BB,CPK-BB)、神经元特异性烯醇化酶(neuron-specific enolase,NSE)、星形胶质源性蛋白(S-100 calcium binding protein,S-100B)在成人病毒性脑炎中表达及与病情、预后关系。方法选取我院收治的成人病毒性脑炎102例为观察组,另纳入同期偏头痛、上呼吸道感染、神经症患者50例为对照组。统计2组及观察组不同病情程度血清和脑脊液GFAP、CPK-BB、NSE、S-100B水平,绘制受试者工作特征曲线(receiver operating characteristic,ROC)及曲线下面积(area under the curve,AUC)分析其预测效能,同时比较不同预后患者血清和脑脊液GFAP、CPK-BB、NSE、S-100B水平,Logistic回归方程分析两者间相关性。结果观察组血清和脑脊液GFAP、CPK-BB、NSE、S-100B含量均高于对照组,且观察组急性期和恢复期重度患者>中度患者>轻度患者(P<0.05);成人病毒性脑炎患者血清和脑脊液GFAP(r=0.587、0.638、0.552、0.568)、CPK-BB(r=0.557、0.593、0.540、0.559)、NSE(r=0.602、0.655、0.587、0.600)、S-100B(r=0.599、0.634、0.575、0.595)含量与急性期、恢复期病情程度呈正相关(P<0.05);ROC曲线显示,脑脊液GFAP、CPK-BB、NSE、S-100B诊断成人病毒性脑炎价值[AUC:0.937]优于血清GFAP、CPK-BB、NSE、S-100B联合诊断价值[AUC:0.908];观察组后遗症患者血清和脑脊液GFAP、CPK-BB、NSE、S-100B高于无后遗症患者(P<0.05);成人病毒性脑炎血清和脑脊液GFAP(OR:4.971、5.311)、CPK-BB(OR:4.986、5.292)、NSE(OR:5.001、4.727)、S-100B(OR:5.453、4.492)与预后密切相关(P<0.05)。结论血清和脑脊液GFAP、CPK-BB、NSE、S-100B在成人病毒性脑炎患者中呈高表达,且与病情程度、预后密切相关,为本病诊治提供有利依据。

关键词：脑炎,病毒性脑脊液血清

Responses of Alpine Wetlands to Climate Changes on the Qinghai-Tibetan Plateau Based on Remote Sensing

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Chinese Geographical Science 2020年第2期30卷 189-201页

作者： WANG Rui he min NIU Zhenguo State Key Laboratory of Remote Sensing Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100101China School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing 100049China

The alpine wetlands in QTP(Qinghai-Tibetan Plateau)have been profoundly impacted along with global climate *** employ satellite datasets and climate data to explore the relationships between alpine wetlands and climate changes based on remote sensing *** show that:1)the wetland NDVI(Normalized Difference Vegetation Index)and GPP(Gross Primary Production)were more sensitive to air temperature than to precipitation *** wetland ET(evapotranspiration)across alpine wetlands was greatly correlated with precipitation rate.2)Alpine wetlands responses to climate changes varied spatially and temporally due to different geographic environments,variety of wetland formation and human disturbances.3)The vegetation responses of the Zoige wetland was the most noticeable and related to the temperature,while the GPP and NDVI of the Qiangtang Plateau and Gyaring-Ngoring Lake were significantly correlated with both temperature and precipitation.4)ET in the Zoige wetland showed a significantly positive trend,while ET in Maidika wetland and the Qiangtang plateau showed a negative trend,implying wetland degradation in those two wetland *** complexities of the impacts of climate changes on alpine wetlands indicate the necessity of further study to understand and conserve alpine wetland ecosystems.

关键词： Qinghai-Tibetan Plateau(QTP) alpine wetlands climate change Moderate-resolution Imaging Spectroradiometer(MODIS) remote sensing

Modification of the spectra of correlated charm-anticharm quark pairs in the quark-gluon plasma

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Chinese Physics C 2020年第5期44卷 56-62页

作者： Ismat Ullah min he Department of Applied Physics Nanjing University of Science and TechnologyNanjing 210094China

heavy quarks play an important role in probing the properties of strongly interacting quark-gluon plasma(QGP)created in ultra-relativistic heavy-ion *** study the interactions of single heavy(charm)quarks and correlated charm and anticharm(ccˉ)quark pairs with the medium constituents of QGP by performing fireball+Langevin simulations of the pertinent Brownian motion with elastic *** studying the traditional observables,the nuclear modification factor and the elliptic flow of single heavy quarks in QGP for different thermal relaxation rates,we also study the broadening of the azimuthal correlations of charm and anticharm quark pairs in the QGP medium for different relaxation rates and transverse momenta *** quantified the smearing of ccˉpair azimuthal correlations with an increasing thermal relaxation rate:while the(nearly)back-to-back correlations among ccˉpairs are almost completely washed out at low transverse momentum(pT),these correlations at high pT largely survive the pair *** provides a novel observable for diagnosing the properties of QGP.

关键词： quark-gluon plasma heavy quarks Brownian motion Langevin simulation

传统泡菜中高效降解核苷乳酸菌的筛选及其特性研究

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食品与发酵工业 2024年第12期50卷 227-233页

作者：李杰张鹏霞周健贺敏彭景贤包艳宋丽新佳木斯大学公共卫生学院黑龙江佳木斯154000 佳木斯大学基础医学院黑龙江佳木斯154000 包头市疾病预防控制中心内蒙古包头014030 内蒙古科技大学包头医学院公共卫生学院内蒙古包头014060

高尿酸血症是一种因尿酸代谢障碍而引发的一种代谢性疾病。乳酸菌作为一类重要的益生菌可通过多种方式改善高尿酸血症。该研究旨在从泡菜中筛选能够高效降解核苷的乳酸菌并分析其特性。利用高效液相色谱法分析所筛选菌株的核苷降解能力... 详细信息

高尿酸血症是一种因尿酸代谢障碍而引发的一种代谢性疾病。乳酸菌作为一类重要的益生菌可通过多种方式改善高尿酸血症。该研究旨在从泡菜中筛选能够高效降解核苷的乳酸菌并分析其特性。利用高效液相色谱法分析所筛选菌株的核苷降解能力,检测菌株对黄嘌呤氧化酶抑制作用、体外环境耐受性及抗生素敏感性。结果表明,短乳杆菌(Levilactobacillus brevis)SLlac-18对肌苷和鸟苷的降解率分别可达97.81%和97.89%;且对黄嘌呤氧化酶的活力具有一定抑制作用。此外,在pH 2.0的环境下,SLlac-18的存活率可达96%;在3 g/L胆盐环境下处理5 h条件下,SLlac-18的存活率可达96.33%;而在胃肠液环境中,SLlac-18同样表现较高的耐受性,存活率均在90%以上,且菌株对红霉素、氨苄西林等4种常见抗生素具有敏感性。短乳杆菌SLlac-18具有潜在降尿酸功能,且具有良好的益生特性,可以应用于高尿酸血症预防和辅助治疗中,具有一定应用价值。

关键词：高尿酸血症核苷乳酸菌泡菜益生菌

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高空菱形翼布局无人机气动特性

上海航天（中英文） 2024年第4期41卷 36-43页

作者：赵炜黄江流贺敏马飞仲康上海机电工程研究所上海201109 上海航天动力技术研究所上海201109

为了获取无人机执行情报、监视和侦察等特种任务时的长航时优势,菱形翼布局无人机受到了大家的极大关注。高空菱形翼布局无人机通过前后翼搭接,能够有效增加整机展弦比,同时由于飞行高度高,飞行速度低,流动存在层流-分离-转捩等特殊流... 详细信息

为了获取无人机执行情报、监视和侦察等特种任务时的长航时优势,菱形翼布局无人机受到了大家的极大关注。高空菱形翼布局无人机通过前后翼搭接,能够有效增加整机展弦比,同时由于飞行高度高,飞行速度低,流动存在层流-分离-转捩等特殊流动现象,流动具有复杂性。本文采用数值模拟方法,对菱形翼布局无人机在低雷诺数下的气动特性进行了研究。结果表明:菱形翼气动布局具有较好的气动特性,存在着前后翼相互干扰的问题。随着前后翼距离靠近,前翼受阻滞、后翼受下洗效应越严重;同时,在大迎角下,后翼受前翼下洗影响流动分离延迟,使整机气动焦点后移,纵向静稳定裕度增大。

关键词：菱形翼布局低雷诺数气动特性阻滞下洗纵向静稳定裕度