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Mlock:building delegable metadata service for the parallel file systems

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Science China(Information Sciences) 2015年第3期58卷 66-79页

作者： zhang quan FENG Dan WANG fang WU Sen Wuhan National Laboratory for Optoelectronics School of Computer Huazhong University of Science and Technology Information & Telecommunication Company State Grid Hubei Electric Power Company

The ever-growing demand for high performance computation calls for progressively larger parallel distributed file systems to match their *** file systems can achieve high performance for large I/O operations through distributing load across numerous data ***,they fail to provide quality service for applications pertaining to small *** this paper,we propose a delegable metadata service(DMS)for hiding latency of metadata accesses and optimizing small-file *** addition,four techniques have been designed to maintain consistency and efficiency in DMS:pre-allocate serial metahandles,directory-based metadata replacement,packing transaction operations and fine-grained lock *** schemes have been employed in Cappella parallel distributed file system,and various experiments complying with industrial standards have been conducted for evaluation of its *** results show that our design has achieved significant improvement in performance of both metadata operations and small-file ***,this scheme is widely applicable for integration within many other distributed file systems.

关键词： delegable metadata service metadata performance consistency small file parallel file system

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一种压电陶瓷弯曲元剪切波速测试装置的开发

实验技术与管理 2008年第8期25卷 59-62,98页

作者：张泉芳陈佩杭姬美秀黄博浙江大学土木水利工程实验中心浙江杭州310027 浙江大学软弱土与环境土工教育部重点实验室浙江杭州310027 宁波市文物保护管理所浙江宁波315010 浙江省建筑科学设计研究院有限公司浙江杭州310012

压电陶瓷弯曲元是一种多功能传感器，在国外已经被应用于测试土的剪切波速和研究土的工程性质。该文介绍了在HX-100型动三轴仪上开发的压电陶瓷弯曲元剪切波速的测试装置，并对多种不同物理性质的试样，用弯曲元测试装置进行试验，试验... 详细信息

压电陶瓷弯曲元是一种多功能传感器，在国外已经被应用于测试土的剪切波速和研究土的工程性质。该文介绍了在HX-100型动三轴仪上开发的压电陶瓷弯曲元剪切波速的测试装置，并对多种不同物理性质的试样，用弯曲元测试装置进行试验，试验结果与共振柱仪室内试验的结果非常吻合。同时，利用此试验装置，参与了国际平行试验，并获得好评。

关键词：压电陶瓷弯曲元 HX-100型动三轴仪小应变剪切模量

One year results of presbyLASIK using hybrid bi-aspheric micro-monovision ablation profile in correction of presbyopia and myopic astigmatism

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International Journal of Ophthalmology(English edition) 2020年第2期13卷 271-277页

作者： fang Liu Ting zhang quan Liu State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CentreSun Yat-sen UniversityGuangzhou 510060Guangdong ProvinceChina

●AIM:To analyze one year clinical outcomes and subjective rating of hybrid bi-aspheric multifocal central presbyLASIK with micro-monovision for correction of presbyopia and myopic astigmatism.●METHODS:Seventy-four eyes of 37 patients consecutively treated with presbyLASIK were *** mean age of the patients was 43.8±3.0 y with a mean spherical equivalent refraction of-5.21±1.87 diopters(D)and mean astigmatism of-0.82±0.64 *** acuity,manifest refraction,contrast sensitivity,aberrometry and patients’subjective rating were evaluated pre-and postoperatively.●RESULTS:At 1 y postoperatively(68 eyes of 34 patients),the mean spherical equivalent(SE)refraction in distance eyes was 0.06±0.05 D,whereas the achieved SE in near eyes was-0.83±0.05 ***-nine percent of eyes were within±0.50 D of target correction of *** binocular mean uncorrected distance visual acuity(UDVA)was 0.00±0.18 logMAR(20/20).Sixty-four percent of patients achieved 0.0 logMAR(20/20)or better of UDVA and 0.1 logRAD or better of UNVA as *** was a binocularly loss of one line CDVA after surgery for only one patient(3%,1/34)and no patient lost 2 *** changes in binocular contrast sensitivity(CS)in all test conditions were not significant at any frequency after *** changes of entire eye total higher order aberrations(tHOA)and spherical aberrations(SA)significantly higher in near eyes than in distance *** overall satisfaction score for surgery was 93±8.●CONCLUSION:The hybrid bi-aspheric multifocal central presby LASIK with micro-monovision appears to be an efficacious option for myopic *** year postoperative outcomes in a relatively young presbyopia population indicate improvements in both far and near vision with high satisfaction.

关键词： presbyLASIK presbyopia monovison myopia

应用多重实时荧光PCR方法对8种动物毛纤维种类鉴别的研究

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畜牧兽医学报 2018年第7期49卷 1540-1549页

作者：刘艳艳范阳阳步迅胡悦东野升金谭晴晴张全芳山东省农业科学院生物技术研究中心/山东省农业科学院应用生命科学实验室济南250100

本研究旨在利用多重实时荧光PCR方法对水貂、狐狸、骆驼、兔、山羊、绵羊、鸭和鹅8种动物毛纤维进行物种鉴定研究。利用碱裂解法加入二硫苏糖醇,并结合硅珠吸附核酸法来优化动物毛纤维DNA的提取;根据8种动物16S rDNA基因特异核苷酸序列... 详细信息

本研究旨在利用多重实时荧光PCR方法对水貂、狐狸、骆驼、兔、山羊、绵羊、鸭和鹅8种动物毛纤维进行物种鉴定研究。利用碱裂解法加入二硫苏糖醇,并结合硅珠吸附核酸法来优化动物毛纤维DNA的提取;根据8种动物16S rDNA基因特异核苷酸序列设计通用PCR引物和特异性TaqMan荧光探针;通过优化引物和探针浓度及退火温度等PCR反应体系和条件,建立了多重实时荧光PCR检测体系;并对多重PCR体系的特异性、灵敏度、重复性和适用性进行评估。结果表明,使用SDS-二硫苏糖醇DTT-蛋白酶K结合Chelex-100法,并利用硅珠纯化提取动物毛纤维DNA效果最佳,满足实时荧光PCR检测要求。本方法 DNA灵敏度为0.01ng,混合样本方法检出限为1.0%。因此本方法能够从动物毛纤维提取高质量DNA,建立的多重实时荧光PCR检测体系具有特异性强、重复性好和灵敏度高等优势。本方法可用于水貂、狐狸、骆驼、兔、山羊、绵羊、鸭和鹅8种动物及其混合物毛纤维的鉴定,为拓展动物毛纤维在物种识别、分子进化研究、分子标记辅助育种和遗传资源评价等领域中的应用奠定基础。

关键词：动物毛纤维多重实时荧光PCR 鉴定

Spatial dependence of high energy electrons and their radiations in pulsar wind nebulae

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Research in Astronomy and Astrophysics 2016年第6期16卷 47-58页

作者： fang-Wu Lu quan-Gui Gao Li zhang Department of Astronomy Key Laboratory of Astroparticle Physics of Yunnan ProvinceYunnan University Department of Physics Yuxi Normal University

We investigate the spatial dependence of high energy electrons and their radiations in pulsar wind nebulae （PWNe）. By assuming a time-dependent broken power-law injection and spatial dependence of convection velocity, magnetic field strength and diffusion coefficient on the radial distance of an expand- ing system, we numerically solve the Fokker-Planck transport equation including convection, diffusion, adiabatic loss and radiative loss in spherical coordinates, and investigate the effects of magnetic field, PWN age, maximum energy of electrons, and diffusion coefficient on electron spectra and non-thermal photon emissions. Our results indicate that （1） electron spectra and the corresponding photon spectra are a function of radial distance r of the expanding system; （2） for a given expansion velocity, the increase of the PWN age causes a slower decrease of the convection velocity （V ∝ r-β） and a more rapid decrease of the magnetic field strength （B ∝ r-1＋β）, but a more rapid increase of the diffusion coefficient （k∝ r1-β） because the index β decreases with the PWN age; and （3） the lower energy part of the electron spectra is dominated by convection and adiabatic loss, but the higher energy part is dominated by the competition between syn- chrotron loss and diffusion, and such a competition is a function of radial distance. Therefore the diffusion effect has an important role in the evolution of electron spectra as well as non-thermal photon spectra in a PWN.

关键词： diffusion -- ISM: supernova remnants -- pulsars: general -- radiation mechanisms: non-thermal

药用贝母属系统发育关系分析及多重实时荧光PCR检测方法的建立

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中草药 2019年第9期50卷 2172-2180页

作者：刘艳艳张全芳范阳阳谭晴晴姜欣欣汪冰葛付存林永强步迅张永清山东农业科学院生物技术研究中心中药分子鉴定公共服务平台山东济南250100 山东省食品药品检验研究院山东济南250101 山东百味堂中药饮片有限公司山东济南250108 山东中医药大学药学院天然药物研究所山东济南250355

目的探讨多重实时荧光PCR检测方法对川贝母及伪品鉴别的可行性。方法通过对常见贝母属植物的ITS、psb Atrn H、rbc L和matK基因序列种间变异、遗传距离及系统发育关系分析,选择进化速率快、种间变异大、种内变异小的基因作为靶基因,设... 详细信息

目的探讨多重实时荧光PCR检测方法对川贝母及伪品鉴别的可行性。方法通过对常见贝母属植物的ITS、psb Atrn H、rbc L和matK基因序列种间变异、遗传距离及系统发育关系分析,选择进化速率快、种间变异大、种内变异小的基因作为靶基因,设计川贝母及伪品贝母的特异性引物和Taqman探针,建立一种多重实时荧光PCR检测方法。通过特异性、灵敏度及混合样本检测与测序方法比较进行方法评估。结果贝母属ITS和psb A-trn H变异位点高于rbc L和mat K,通过遗传距离分析rbc L和mat K基因显著低于ITS和psb A-trn H基因,以ITS作为靶基因,建立多重实时荧光PCR检测方法特异性强,灵敏度达0.01ng,对18份样本抽查检出4份伪品贝母,检测结果与构建的NJ树聚类分析结果完全一致。结论基于ITS区域序列为靶基因建立多重实时荧光PCR检测方法能够成功鉴定川贝母及其混伪品,为川贝母真伪鉴别提供依据。

关键词： ITS psbA-trnH rbcL matK 多重实时荧光PCR 川贝母混伪品

牛、羊肉中水貂、猪、鼠混杂成分的多重荧光PCR鉴定方法的建立

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农业生物技术学报 2018年第9期26卷 1621-1630页

作者：胡悦刘艳艳任金瑞陈蕾范阳阳张全芳陈雪燕步迅山东省农业科学院生物技术研究中心山东省农业科学院畜牧兽医研究所

针对现阶段肉类食品市场中出现的以劣充优的掺假问题,通过视觉、触觉、嗅觉和味觉等传统方法来鉴定肉的外观、色泽、气味和硬度,已不能满足现阶段肉类质量和源性的鉴别要求。基于现代分析仪器和生物技术的肉类掺假识别方法主要包括:基... 详细信息

针对现阶段肉类食品市场中出现的以劣充优的掺假问题,通过视觉、触觉、嗅觉和味觉等传统方法来鉴定肉的外观、色泽、气味和硬度,已不能满足现阶段肉类质量和源性的鉴别要求。基于现代分析仪器和生物技术的肉类掺假识别方法主要包括:基于蛋白质的检测方法、酶联免疫吸附试验(Enzyme linked immunosorbent assay,ELISA)、色谱分析方法和基于DNA序列的分子生物学检测方法。其中,基于DNA序列的分子生物学检测方法特别是荧光PCR法具有特异性强、灵敏度高,快速准确的优点。本实验运用了多重荧光PCR的技术,建立了检测牛羊肉类中掺杂水貂(Mustela lutreola)、猪(Sus scrofa)、鼠(Mus musculus)3种动物源性成分的检测方法。在3种动物源性的线粒体16S r DNA的保守区设计了一对通用引物,在可变区设计了水貂、猪、鼠3种物种特异性的分子信标探针,分别进行了探针的特异性验证、实验体系的灵敏度验证和样品的检出限实验。特异性验证中,3种探针均可有效排除其他物种DNA的干扰,特异扩增;灵敏度验证实验中,设置了7个DNA浓度稀释梯度,每个梯度6个重复,确定了该体系的灵敏度为0.01 ng/μL;样品检出限实验中,设置了3种掺杂方式,每种方式7个不同的掺杂质量比,每个质量比4个平行样,确定了本实验的样品检测灵敏度可达到1%(质量比)。本研究结果显示,本方法能特异、准确、灵敏地鉴别出牛羊肉中水貂、猪和鼠的掺杂成分,为多物种的源性鉴别提供了科学依据。

关键词：多重实时荧光PCR 源性鉴定水貂、猪和鼠源性成分

VR content creation and exploration with deep learning: A survey

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Computational Visual Media 2020年第1期6卷 3-28页

作者： Miao Wang Xu-quan Lyu Yi-Jun Li fang-Lue zhang State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijing 100191China. Peng Cheng Laboratory Shenzhen 518000China School of Engineering and Computer Science Victoria University of WellingtonNew Zealand

Virtual reality(VR)offers an artificial,computer generated simulation of a real life *** originated in the 1960 s and has evolved to provide increasing immersion,interactivity,imagination,and *** deep learning systems are able to represent and compose information at various levels in a deep hierarchical fashion,they can build very powerful models which leverage large quantities of visual media *** of VR methods and applications has been significantly boosted by the recent developments in deep learning *** content creation and exploration relates to image and video analysis,synthesis and editing,so deep learning methods such as fully convolutional networks and general adversarial networks are widely employed,designed specifically to handle panoramic images and video and virtual 3 D *** article surveys recent research that uses such deep learning methods for VR content creation and *** considers the problems involved,and discusses possible future directions in this active and emerging research area.

关键词： virtual reality deep learning neural networks 360°image and video virtual content

基于荧光SSR标记的玉米自交系遗传结构解析

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植物遗传资源学报 2017年第1期18卷 19-31页

作者：张全芳梁水美李燕刘艳艳范阳阳郭庆法鲁守平步迅山东省农业科学院生物技术研究中心/山东省作物遗传改良与生态生理重点试验室济南250100 山东省农业科学院玉米研究所/小麦玉米国家工程试验室/农业部黄淮海北部玉米生物学与遗传育种重点试验室济南250100

利用多重SSR-PCR荧光标记检测技术,对本单位自育和引进的259份玉米自交系进行遗传多样性和亲缘关系分析,并以11个归属于不同杂种优势群的代表自交系为参照进行群体结构分析。结果显示,50对SSR引物共检测到214个等位基因变异,基因多态性... 详细信息

利用多重SSR-PCR荧光标记检测技术,对本单位自育和引进的259份玉米自交系进行遗传多样性和亲缘关系分析,并以11个归属于不同杂种优势群的代表自交系为参照进行群体结构分析。结果显示,50对SSR引物共检测到214个等位基因变异,基因多态性指数的平均值为0.50,每个SSR标记的多态性信息量(PIC)平均值为0.44。用UPGMA方法将270份自交系划分成3大类群,进一步进行数值化杂种优势群分析,以明确所用种质资源的杂优类群利用方向,为玉米自交系的有效利用和品种的选育提供依据。

关键词：玉米自交系分子标记遗传多样性