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Skeleton Marching-based Parallel Vascular Geometry Reconstruction Using Implicit Functions

国际自动化与计算杂志：英文版 2020年第1期17卷 30-43页

作者： quan Qi qing-De Li Yongqiang Cheng qing-Qi Hong College of Information Science and Technology Shihezi UniversityShihezi 832003China Department of Computer Science and Technology University of HullHull HU67RXUK Software School Xiamen UniversityXiamen 361005China

Fast high-precision patient-specific vascular tissue and geometric structure reconstruction is an essential task for vascular tissue engineering and computer-aided minimally invasive vascular disease diagnosis and *** this paper,we present an effective vascular geometry reconstruction technique by representing a highly complicated geometric structure of a vascular system as an implicit *** implicit geometric modelling,we are able to reduce the complexity and level of difficulty of this geometric reconstruction task and turn it into a parallel process of reconstructing a set of simple short tubular-like vascular sections,thanks to the easy-blending nature of implicit geometries on combining implicitly modelled geometric *** basic idea behind our technique is to consider this extremely difficult task as a process of team exploration of an unknown environment like a *** on this idea,we developed a parallel vascular modelling technique,called Skeleton Marching,for fast vascular geometric *** the proposed technique,we first extract the vascular skeleton system from a given volumetric medical image.A set of sub-regions of a volumetric image containing a vascular segment is then identified by marching along the extracted skeleton tree.A localised segmentation method is then applied to each of these sub-image blocks to extract a point cloud from the surface of the short simple blood vessel segment contained in the image *** small point clouds are then fitted with a set of implicit surfaces in a parallel manner.A high-precision geometric vascular tree is then reconstructed by blending together these simple tubular-shaped implicit surfaces using the shape-preserving blending *** results show the time required for reconstructing a vascular system can be greatly reduced by the proposed parallel technique.

关键词： Vascular geometric reconstruction implicit modelling parallel computing high-performance high-accuracy

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不同分辨率CWRF模式对中国区域气温模拟的比较研究

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气候变化研究进展 2024年第2期20卷 129-145页

作者：董李丽张焓李清泉汪方赵崇博谢冰中国气象局气候预测研究重点开放实验室国家气候中心北京100081 中山大学大气科学学院珠海519082 南京信息工程大学气象灾害预报预警与评估协同创新中心南京210044

针对现有区域气候模式分辨率较为粗糙的现状,瞄准精细化气候预测和服务的需求,基于30 km分辨率CWRF区域气候模式研发了水平分辨率和下垫面信息进一步精细化至15 km的新版本模式,利用欧洲中期预报中心的ERAInterim大气再分析资料和美国的... 详细信息

针对现有区域气候模式分辨率较为粗糙的现状,瞄准精细化气候预测和服务的需求,基于30 km分辨率CWRF区域气候模式研发了水平分辨率和下垫面信息进一步精细化至15 km的新版本模式,利用欧洲中期预报中心的ERAInterim大气再分析资料和美国的OISSTv2.表面温度资料驱动两种版本的CWRF模式,与中国均一化气温数据集CN05.1的观测数据相比,系统分析了CWRF模式对1982.2.16年中国区域2.气温的模拟效果及其对水平分辨率和下垫面信息的敏感性。结果表明:单纯修改模式的下垫面信息,不提高模式分辨率,对模拟结果的影响不大;将分辨率提高至15 km的CWRF模式对地形复杂区域的气温模拟效果更好,对气温的空间分布、年际变化以及极端气温的模拟都有较好的表现。从气候平均气温分布看,与30 km CWRF模式相比,在春、秋、冬季西南地区和青藏高原,以及夏季西南、华南、华中等冷偏差较为显著的地区,15 km模式模拟结果将冷偏差减小到1℃以内;从气温年际变化来看,15km模式对夏季华中、华北和东北南部地区及冬季气温的模拟结果优于30km模式,相关系数最高提升0.4;在极端事件的模拟方面,与30 km模式相比,15 km模式对于在华南到福建、江西、湖南、湖北东部的夏季日数极大值区域模拟具有较大的改善,均方根误差减小1 d;对于新疆东部、东北的极端高温和新疆、青藏高原、华南的极端低温模拟也有明显改善,均方根误差减小1℃。因此,高分辨率区域气候模式有利于提高中国气温的精细化模拟能力。

关键词：中国区域模式水平分辨率气温极端事件

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基于PCA和ICA模式融合的非高斯特征检测识别

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自动化学报 2024年第1期50卷 169-180页

作者：葛泉波程惠茹张明川郑瑞娟朱军龙吴庆涛南京信息工程大学自动化学院南京210044 江苏省大气环境与装备技术协同创新中心南京210044 江苏省大数据分析技术重点实验室南京210044 河南科技大学信息工程学院洛阳471023

针对无人船(Unmanned surface vehicle,USV)航行位姿观测数据的非高斯性/高斯性判别问题,提出一种基于主成分分析(Principal component analysis,PCA)和独立成分分析(Independent component analysis,ICA)模式融合的非高斯特征检测识别方法.首先,采用基于标准化加权平均和信息熵的数据预处理方法.其次,引入混合加权核函数并使用灰狼优化(Grey wolf optimization,GWO)算法进行参数优化,以提高PCA方法的准确性.同时,该算法采用一种新的非线性控制因子策略,提高全局和局部搜索能力.最后,建立了一种基于ICA和PCA联合的相关性分析方法来实现多维数据的降维,在降维数据的基础上综合T型多维偏度峰度检验法和KS(Kolmogorov-Smirnov)检验法进行非高斯性/高斯性特征检测识别.该方法考虑了非线性非高斯的噪声对降维结果精确度的影响,有效降低了多维数据非高斯检测的复杂度,同时也为后续在实际USV位姿估计等应用中提供了保障.实验表明,该方法具有较高的准确性和稳定性,可为USV航行位姿观测数据处理提供支持.

关键词：主成分分析混合核函数灰狼优化算法高维降维非高斯

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有氧运动对育肥期滩羊小肠微生物丰度的影响

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饲料研究 2024年第1期47卷 73-79页

作者：赵正伟陈茂良张连全马青宁夏农林科学院动物科学研究所宁夏银川750002 宁夏瑞牧盐池滩羊购销有限公司宁夏吴忠751100

试验旨在探讨有氧运动对育肥期滩羊小肠肠道微生物丰度及功能的影响。选取同期断奶体重(16±2.kg的滩羊母羔羊60只,随机分为3组,每组2.只。试验1组滩羊每日运动8~10 km,试验2.滩羊每日运动4~6 km,对照组滩羊全舍饲。试验期130 d。结果... 详细信息

试验旨在探讨有氧运动对育肥期滩羊小肠肠道微生物丰度及功能的影响。选取同期断奶体重(16±2.kg的滩羊母羔羊60只,随机分为3组,每组2.只。试验1组滩羊每日运动8~10 km,试验2.滩羊每日运动4~6 km,对照组滩羊全舍饲。试验期130 d。结果显示,与对照组相比,试验1组滩羊十二指肠、空肠和回肠3个部位OTU个数均升高。与对照组相比,试验1组十二指肠和试验2.空肠食糜中变形菌门相对丰度显著升高(P2.回肠食糜中放线菌门相对丰度显著升高(P2.十二指肠食糜中粪球菌属相对丰度显著降低(P2.十二指肠食糜中Solobacterium菌属丰度极显著降低(P2.空肠食糜中真杆菌属相对丰度极显著降低(P<0.01)。研究表明,育肥期滩羊每日有氧运动8~10 km可以提升小肠菌群丰度多样性,提高小肠有益菌菌群丰度,降低有害菌群丰度,改善小肠健康水平。

关键词：滩羊有氧运动 16S rRNA 小肠菌群多样性丰度

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Stress-corrosion behavior and characteristics of the friction stir welding of an AA2.98-T34 alloy

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International Journal of Minerals,Metallurgy and Materials 2020年第6期27卷 774-782页

作者： quan-qing Zeng Song-sheng Zeng Dong-yao Wang Research Institute of Light Alloy Central South UniversityChangsha 410083China Key Laboratory of the Ministry of Education of Nonferrous Metals Central South UniversityChangsha 410083China Technology Center Valin ArcelorMittal Automotive Steel Co.Ltd.Loudi 417009China

To better understand the stress-corrosion behavior of friction stir welding(FSW),the effects of the microstructure on the stress-corrosion behavior of the FSW in a 2.98-T34 aluminum alloy were *** experimental results show that the low-angle grain boundary(LABs)of the stir zone(SZ)of FSW is significantly less than that of heated affected zone(HAZ),thermo-mechanically affected zone(TMAZ),and parent materials(PM),but the grain boundary precipitates(GBPs)T1(Al2.uLi)were less,which has a slight effect on the stress *** dislocation density in SZ was greater than that in other *** residual stress in SZ was+67 MPa,which is greater than that in the *** residual stress in the HAZ and PM is-8 MPa and-32.MPa,respectively,and both compressive *** corrosion potential in SZ is obviously less than that in other ***,micro-cracks were formed in the SZ at low strain rate,which indicates that the grain boundary characters and GBPs have no significant effect on the crack initiation in the stress-corrosion process of the ***,the residual tensile stress has significant effect on the crack initiation during the stress-corrosion process.

关键词： slow strain rate test residual stress grain boundary characteristic AA2.98-T34 alloy friction stir welding

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调强放疗对乳腺癌根治术患者的治疗效果研究

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四川生理科学杂志 2024年第8期46卷 1787-1789页

作者：曹静丁权常青义驻马店市第一人民医院肿瘤放疗科河南驻马店463000 驻马店市第一人民医院肿瘤科河南驻马店463000

目的:探讨调强放疗对乳腺癌根治术患者的影响。方法:选取2.2.年6月~2.2.年6月期间本院收治的76例乳腺癌根治术患者作为研究对象。采用随机数字表法将患者分为对照组和观察组,每组各38例。对照组采取常规放疗治疗;观察组采取调强放疗治... 详细信息

目的:探讨调强放疗对乳腺癌根治术患者的影响。方法:选取2.2.年6月~2.2.年6月期间本院收治的76例乳腺癌根治术患者作为研究对象。采用随机数字表法将患者分为对照组和观察组,每组各38例。对照组采取常规放疗治疗;观察组采取调强放疗治疗。分析对比两组的疗效、放疗相关不良反应以及生活质量。结果:观察组的治疗总有效率显著高于对照组(P<0.05)。观察组的不良反应发生率率显著低于对照组(P<0.05)。观察组的SF-36评分显著高于对照组(P<0.05)。结论:乳腺癌根治术治疗乳腺癌术后给予患者调强放疗,能提高治疗效果,减少放疗相关不良反应,提高患者生活质量。

关键词：乳腺癌根治术调强放疗治疗效果放疗相关不良反应生活质量

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Effect of interface behaviour on damage and instability of PBX under combined tension-shear loading

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Defence Technology（防务技术） 2023年第5期23卷 137-151页

作者： quan-zhi Xia Yan-qing Wu Feng-lei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081PR China

To study the effect of interface behaviour on the mechanical properties and damage evolution of PBX under combined tension-shear loading, the present work establishes the numerical model of a PBX three-phase hybrid system, which introduces a nonlinear plastic damage cohesion model to study the mechanical response and damage process. The parameters in the model were fitted and *** the crack growth rate as the feature, the damage state in each stage was determined, and the damage instability criterion was given. The effects of interfacial tensile strength and shear strength on the damage process of PBX were studied. On this basis, serrated and hemispherical structures interface of PBX has been developed, which affects the damage process and instability during the loading *** results indicate that damage state response of PBX experiences the process of stable load bearing,unstable propagation, and complete failure. At the critical moment of instability, the overall equivalent effective strain of material reaches 302. με and instability loading displacement reaches 0.39 mm. The increase of interfacial tensile strength and shear strength significantly inhibits the damage of PBX. The effect of interfacial shear strength on critical instability of PBX is approximately 1.7 times that of the interfacial tensile strength. Further, interface opening along the normal direction is the main damage form at the interface. Serrated and hemispherical rough interfaces can significantly inhibit propagation of cracks, and the load bearing capacity is improved by 2.% and 9.7%, respectively. Appropriate improvement of the roughness of the interface structure can effectively improve the mechanical properties. It is significantly important to have a better understanding of deformation, damage and failure mechanisms of PBX and to improve our predictive ability.

关键词： PBX explosives Interface behaviour Damage Instability Crack propagation

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Multi-track Storage of 10000 Holograms in a Disk-Type Photorefractive Crystal

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Chinese Physics Letters 2000年第9期17卷 675-677页

作者： TAO Shi-quan XU Min LIU Guo-qing YUAN quan JIANG Zhu-qing Applied Physics Department Beijing Polytechnic UniversityBeijing 100022

Three-dimensional disk-type holographic storage using spatioangular multiplexing with a spherical reference beam is analyzed and experimentally *** overlapping factors between adjacent holograms in a track and between adjacent tracks in a disk are determined based on the selective angles calculated by coupled-wave *** are 10000 holograms stored along 5 tracks in a sector of a single iron-doped lithium niobate crystal.

关键词： theory. holographic lithium

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A novel method to prepare SPR sensor chips based on photografting molecularly imprinted polymer

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Chinese Chemical Letters 2011年第6期22卷 721-724页

作者： qing quan Wei Tian Xin Wei Key Laboratory of Cluster Science of Ministry of Education Beijing Institute of Technology Beijing 100081 China

A novel method to prepare surface plasmon resonance（SPR） sensor chips based on grafted imprinted polymer is explored. Benzophenone photografting system is used to grow molecularly imprinted polymer（MIP） films from the modified surface of gold *** surface morphology and thickness of MIP films were investigated by scanning electronic microscope（SEM）.The adsorption properties of sensor chip were studied by SPR *** results demonstrate that nano-MIP films can be constructed on the surface of gold substrate with the good adsorption of template molecules.

关键词： Surface plasmon resonance Molecularly imprinted polymer Photografting

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Correction to Hawking Radiation Characteristics of Stationary Demianski-Newman Black Hole

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Communications in Theoretical Physics 2006年第6期45卷 1026-1030页

作者： JIANG qing-quan YANG Shu-Zheng Institute of Theoretical Physics China West Normal University Nanchong 637002 China

The pure thermal spectrum in dragging coordinate system and the tunneling radiation characteristics across the event horizon for stationary Demianski-Newman black hole are researched. The result shows that the tunneling rate of the particle is relevant to Bekenstein-Hawking entropy, and the derived radiate spectrum is not strictly pure thermal, but is consistent with underlying unitary theory. Finally, we use the obtained results to reduce to stationary Kerr black hole and static Schwarzschild black hole, and lind that only when ignoring the spectrum at higher energies is the tunneling radiation spectrum consistent with Hawking pure thermal one.

关键词： Demianski-Newman black hole energy conservation angular momentum conservation tunneling rate Bekenstein-Hawking entropy

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