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The Varieties of Semi-Conformal Vectors of Rank-One Even Lattice Vertex Operator Algebras
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作者 CHU Yan-jun GAO Yi-bo 《Chinese Quarterly Journal of Mathematics》 2025年第1期36-48,共13页
In this paper,we shall study structures of even lattice vertex operator algebras by using the geometry of the varieties of their semi-conformal vectors.We first give the varieties of semi-conformal vectors of a family... In this paper,we shall study structures of even lattice vertex operator algebras by using the geometry of the varieties of their semi-conformal vectors.We first give the varieties of semi-conformal vectors of a family of vertex operator algebras V_(√kA_(1)) associated to rank-one positive definite even lattices √kA_(1) for arbitrary positive integers k to characterize these even lattice vertex operator algebras.In such a family of lattice vertex operator algebras V_(√kA_(1)),the vertex operator algebra V_(√2A_(1)) is different from others.Hence we describe the varieties of semi-conformal vectors of V_(√2A_(1)) and the fixed vertex operator subalgebra V^(+)√2A_(1).Moreover,as applications,we study the relations between vertex operator algebras V_(√kA_(1) )and L_(sl_(2))(k,0)for arbitrary positive integers k by the viewpoint of semi-conformal homomorphisms of vertex operator algebras.For case k=2,in the series of rational simple affine vertex operator algebras L_(sl_(2))(k,0)for positive integers k,we show that L_(sl_(2))(2,0)is a unique frame vertex operator algebra with rank 3. 展开更多
关键词 vertex operator algebra Semi-conformal vector Affine variety
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折叠超立方体的4-限制连通度
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作者 刘景昭 《曲阜师范大学学报(自然科学版)》 2026年第1期56-66,共11页
图G的h-限制连通度κh(G)是一般连通度κ(G)的推广.n-维折叠超立方体FQn是n-维超立方体Qn的一个变种.该文证明了:对n≥7,h=4,折叠超立方体的4-限制连通度是16n-48.最后给出了一个猜想:对h≥0,n≥4,且n≥h+3,FQn的h-限制连通度是2h(n+1-h).
关键词 限制连通度 限制点割 折叠超立方体 HAMMING距离
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Vertex治疗齿状突骨折伴寰枢椎脱位的早期并发症分析 被引量:7
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作者 康建平 王清 +1 位作者 冯大雄 陈歌 《中国矫形外科杂志》 CAS CSCD 北大核心 2006年第10期746-747,共2页
[目的]分析Vertex治疗齿状突骨折伴寰枢椎脱位的早期并发症发生的原因和预防措施。[方法]对18例齿状突骨折伴寰枢椎脱位中的5例6项术中和术后早期发生的椎动脉损伤、失语、失明、大出血、置钉错误等并发症的原因进行分析,避免并发症的... [目的]分析Vertex治疗齿状突骨折伴寰枢椎脱位的早期并发症发生的原因和预防措施。[方法]对18例齿状突骨折伴寰枢椎脱位中的5例6项术中和术后早期发生的椎动脉损伤、失语、失明、大出血、置钉错误等并发症的原因进行分析,避免并发症的发生。[结果]所有发生的早期并发症都得到相应治疗,未遗留后遗症。[结论]Vertex治疗齿状突骨折伴寰枢椎脱位的早期并发症均可以预防,一旦发生及时治疗效果满意。 展开更多
关键词 vertex 寰枢椎脱位 齿状突骨折 手术 并发症
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Vertex钉棒系统应用于颈椎单开门椎管扩大椎板成形术疗效分析 被引量:4
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作者 许楠健 徐荣明 +1 位作者 马维虎 梁彪 《中国修复重建外科杂志》 CAS CSCD 北大核心 2011年第12期1440-1444,共5页
目的评价Vertex钉棒系统在颈椎单开门椎管扩大椎板成形术中临床应用价值及近期疗效。方法 2008年2月-2010年1月,对28例颈椎疾病患者行后路单开门椎管扩大椎板成形术,开门侧应用侧块螺钉(Vertex钉棒系统)固定,对侧掀开椎板用棘突椎板螺钉... 目的评价Vertex钉棒系统在颈椎单开门椎管扩大椎板成形术中临床应用价值及近期疗效。方法 2008年2月-2010年1月,对28例颈椎疾病患者行后路单开门椎管扩大椎板成形术,开门侧应用侧块螺钉(Vertex钉棒系统)固定,对侧掀开椎板用棘突椎板螺钉(Vertex钉棒系统)固定。男16例,女12例;年龄42~77岁,平均61.3岁。脊髓型颈椎病15例,后纵韧带骨化症5例,颈椎病伴椎管狭窄8例。病程2个月~11年。手术开门减压节段均为C3~7。记录手术时间、术中出血量,采用日本骨科协会(JOA)17分法评定神经功能,并进行颈椎曲度及椎板开门角度测量。结果手术时间为(142.5±22.8)min,术中出血量为(288.2±55.1)mL。患者切口均Ⅰ期愈合。28例均获随访,随访时间14~25个月,平均22个月。术后1周及1年CT示所有患者均无再关门现象,钉棒系统位置良好,无松动、拔出和断裂;术后1年门轴侧骨性融合率为89.3%(25/28)。术后1周及1年JOA评分改善率分别为29.5%±15.0%和64.9%±28.1%,差异有统计学意义(t=0.810,P=0.000)。所有患者均未出现C5神经根麻痹现象。术前、术后1周及1年的颈椎曲度分别为(24.29±5.04)、(23.89±3.57)、(23.41±3.35)°,各时间点间比较差异均无统计学意义(P>0.05)。术后1周及1年椎板开门角度分别为(27.90±4.74)°和(28.07±4.21)°,比较差异无统计学意义(t=—0.176,P=0.862)。结论 Vertex钉棒系统可以有效防止单开门椎管扩大椎板成形术后再关门,减少颈椎曲度的丢失,近期疗效满意。 展开更多
关键词 vertex钉棒系统 脊髓型颈椎病 单开门椎管扩大椎板成形术
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Vertex内固定系统治疗寰枢椎不稳:临床效果与植入物特征的关系 被引量:2
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作者 康建平 冯大雄 王清 《中国组织工程研究与临床康复》 CAS CSCD 北大核心 2007年第1期180-181,F0003,共3页
文章探讨了Vertex内固定系统植入治疗寰枢椎不稳定的临床效果与植入物材料学性能的相关性。选择2004-01/2006-01泸州医学院附属医院收治的寰枢椎脱位与不稳26例患者,采用美国美敦力·枢法模·丹历公司生产的Vertex颈椎后路钉棒... 文章探讨了Vertex内固定系统植入治疗寰枢椎不稳定的临床效果与植入物材料学性能的相关性。选择2004-01/2006-01泸州医学院附属医院收治的寰枢椎脱位与不稳26例患者,采用美国美敦力·枢法模·丹历公司生产的Vertex颈椎后路钉棒内固定系统进行手术。对26例寰枢椎脱位患者采用Vertex内固定及寰枢椎融合术,摄动力位X射线片及CT检查寰枢椎稳定程度,记录每一例患者的术中并发症,术后功能恢复及融合情况。结果:①22例患者术后3个月X射线片显示寰枢融合成功,3例患者术后6个月X射线片显示寰枢融合成功,1例患者1年后植骨吸收再手术植骨,在术后3个月融合成功。②无脊髓损伤加重等并发症,术前JOA17分法评定脊髓功能3~17分,平均6.8分,术后为5~17分,平均14.8分,改善率83%。③26例患者颈部伸屈运动正常,旋转功能均有部分丢失,18例患者旋转达120°,6例患者旋转达100°,1例患者旋转达60°。Vertex内固定系统是颈椎后路钉棒内固定系统,因其具有万向螺钉和随意塑行的棒相连接,做到了固定可靠,节段长短随意和钉棒连接方便的临床应用优点。Vertex内固定系统治疗寰枢椎脱位术后效果亦比较理想。 展开更多
关键词 vertex 寰枢关节 脱位 齿状突骨折 内固定
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Vertex内固定系统治疗齿状突骨折伴寰枢椎脱位病人的护理 被引量:3
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作者 徐春华 王淑敏 张军智 《护士进修杂志》 北大核心 2009年第21期1967-1968,共2页
关键词 vertex内固定系统 齿状突骨折 寰枢椎脱位 护理
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导航下后路Vertex椎弓根螺钉在Hangman骨折治疗中的应用 被引量:1
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作者 霍智铭 关宏刚 +3 位作者 曹正霖 梁亮科 付忠泉 王刚 《岭南现代临床外科》 2012年第3期214-216,共3页
目的探讨导航引导下Vertex椎弓根螺钉在Hangman骨折治疗中的应用。方法分析15例Hangman骨折患者,术中采用后路Vertex椎弓根螺钉进行固定、复位,植骨融合,并结合三维重建导航技术的使用。观察术中有无出现椎动脉或脊髓神经损伤等并发症,... 目的探讨导航引导下Vertex椎弓根螺钉在Hangman骨折治疗中的应用。方法分析15例Hangman骨折患者,术中采用后路Vertex椎弓根螺钉进行固定、复位,植骨融合,并结合三维重建导航技术的使用。观察术中有无出现椎动脉或脊髓神经损伤等并发症,术后复查X线片了解骨折脱位的复位情况,随访观察内固定有无松动、神经功能恢复及植骨融合情况,综合评定该手术的可行性及疗效。结果 15例骨折脱位复位理想,随访5~24个月,内固定均未见松动,除1例植入异体松质骨粒术后14月未能达到骨性融合外,其他病例均达到植骨融合,颈2/3节段获得稳定,4例合并有颈髓损伤的患者术后得到恢复。结论 3D导航下Vertex椎弓根螺钉固定既可避免在置入椎弓根钉时损伤椎动脉及脊髓神经的风险,也可以为骨折脱位提供稳定的三柱固定,是治疗Hangman骨折理想的方法。 展开更多
关键词 导航 HANGMAN骨折 vertex椎弓根螺钉 融合
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Vertex 60 SPECT双探头性能对比 被引量:1
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作者 米文平 张润武 赵晋华 《医疗设备信息》 2002年第7期44-45,共2页
Vertex60SPECT ,其双探头比单探头设备效率提高1倍。在应用中应特别重视双探头性能是否匹配 ,否则其图像反而不及单探头设备。用ADAC公司自带软件 ,对Vertex60SPECT仪的双探头进行性能测试和对比 ,结果各项指标均达到要求 。
关键词 vertex 60 SPECT 双探头性能 测试 对比 匹配
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New Vertex-Degree Condition for Pancyclic Graphs
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作者 顾国华 宋增民 徐新丽 《Journal of Southeast University(English Edition)》 EI CAS 1998年第2期117-120,共4页
Let G be a 2 connected graph with n vertices. In this paper, we prove that if there exist two vertices of any there independent vertices in G such that the sum of whose degree is at least n , then G ... Let G be a 2 connected graph with n vertices. In this paper, we prove that if there exist two vertices of any there independent vertices in G such that the sum of whose degree is at least n , then G is pancyclic, or G is K n/2,n/2 , or G is K n/2,n/2 -e , or G is a cycle of length 5. 展开更多
关键词 pancyclic graph vertex degree independent set bipartite graph
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Neighbourhood Unions and Vertex pancyclicity *
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作者 林文松 宋增民 《Journal of Southeast University(English Edition)》 EI CAS 1998年第1期122-126,共5页
Let G be a 2 connected simple graph of order n ( n ≥5) and minimum degree δ . In this paper, we show that if for any two nonadjacent vertices u , v of G there holds | N(u)∪N(v)|≥n-δ , t... Let G be a 2 connected simple graph of order n ( n ≥5) and minimum degree δ . In this paper, we show that if for any two nonadjacent vertices u , v of G there holds | N(u)∪N(v)|≥n-δ , then G is {3,4} - vertex pancyclic unless G≌K n2,n2 . 展开更多
关键词 CYCLE neighbourhood union vertex pancyclicity
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寰枢椎不稳Vertex内固定术后并发症的观察及护理
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作者 金妲娜 《中国中医骨伤科杂志》 CAS 2014年第2期61-62,共2页
寰枢椎不稳可因创伤、炎症、局部畸形、肿瘤等引起,包括齿突骨折、寰椎椎弓骨折、枢椎椎弓骨折以及因此造成的寰椎脱位等易致颈脊髓受压,甚至威胁患者的生命[1],因此,寰枢椎不稳的患者往往需要采取及时的手术治疗,旨在保证患者的... 寰枢椎不稳可因创伤、炎症、局部畸形、肿瘤等引起,包括齿突骨折、寰椎椎弓骨折、枢椎椎弓骨折以及因此造成的寰椎脱位等易致颈脊髓受压,甚至威胁患者的生命[1],因此,寰枢椎不稳的患者往往需要采取及时的手术治疗,旨在保证患者的生命安全及解除脊髓压迫症状,但由于解剖关系复杂,临近延髓生命中枢,手术难度大,危险性高,术后并发症多,密切观察及细致的护理时术后护理的关键,可影响到手术的成败。我科自2008年8月一2011年9月采用多轴钉棒系统经寰枢椎侧块枢椎椎弓固定(Vertex内固定)治疗寰枢椎不稳共17例,经精心护理,疗效满意,现报告如下。 展开更多
关键词 裹枢椎不稳 vertex内固定 并发症 护理
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利用Vertex Shader技术实现真实的光照效果
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作者 苏蕴 《科技信息》 2010年第27期I0083-I0084,共2页
Vertex Shader代替了标准图形管线中的坐标变换和光照变换阶段,能够实现更为灵活且真实的光照效果。本文使用结合VertexShader技术编程实现了平行光、点光、聚光的顶点光照效果,并与使用标准图形管线实现的光照效果进行了对比。
关键词 计算机图形学 顶点光照 shader程序
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Vertex注塑系统与热凝工艺制作义齿的效果比较 被引量:1
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作者 李刚 杨宏伟 马兰 《山西职工医学院学报》 CAS 2017年第6期38-39,共2页
目的:比较Vertex注塑系统与传统热凝工艺制作的义齿的临床使用效果。方法:随机选取100例无牙颌患者,分别采用这两种工艺制作义齿。随访患者2年,比较两组义齿的折裂,固位及人工牙脱落情况。结果:注塑组的折裂率、固位不良率、人工牙脱落... 目的:比较Vertex注塑系统与传统热凝工艺制作的义齿的临床使用效果。方法:随机选取100例无牙颌患者,分别采用这两种工艺制作义齿。随访患者2年,比较两组义齿的折裂,固位及人工牙脱落情况。结果:注塑组的折裂率、固位不良率、人工牙脱落率均低于传统热凝组。结论:与传统热凝工艺相比,Vertex注塑系统制作的义齿机械性能更稳定,组织适应性好,人工牙不易脱落,能满足临床应用。 展开更多
关键词 传统热凝 vertex注塑 义齿基托
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A dynamic cellular vertex model of growing epithelial tissues 被引量:6
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作者 Shao-Zhen Lin Bo Li Xi-Qiao Feng 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2017年第2期250-259,共10页
Intercellular interactions play a significant role in a wide range of biological functions and processes at both the cellular and tissue scales, for example, embryogenesis, organogenesis, and cancer invasion. In this ... Intercellular interactions play a significant role in a wide range of biological functions and processes at both the cellular and tissue scales, for example, embryogenesis, organogenesis, and cancer invasion. In this paper, a dynamic cellular vertex model is presented to study the morphomechanics of a growing epithelial monolayer. The regulating role of stresses in soft tissue growth is revealed. It is found that the cells originating from the same parent cell in the monolayer can orchestrate into clustering patterns as the tissue grows. Collective cell migration exhibits a feature of spatial correlation across multiple cells. Dynamic intercellular interactions can engender a variety of distinct tissue behaviors in a social context. Uniform cell proliferation may render high and heterogeneous residual compressive stresses, while stress-regulated proliferation can effectively release the stresses, reducing the stress heterogeneity in the tissue. The results highlight the critical role of mechanical factors in the growth and morphogenesis of epithelial tissues and help understand the development and invasion of epithelial tumors. 展开更多
关键词 Soft tissue Cellular vertex model Cell MORPHOGENESIS
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Event vertex and time reconstruction in large-volume liquid scintillator detectors 被引量:9
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作者 Zi-Yuan Li Yu-Mei Zhang +9 位作者 Guo-Fu Cao Zi-Yan Deng Gui-Hong Huang Wei-Dong Li Tao Lin Liang-Jian Wen Miao Yu Jia-Heng Zou Wu-Ming Luo Zheng-Yun You 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第5期51-62,共12页
Large-volume liquid scintillator detectors with ultra-low background levels have been widely used to study neutrino physics and search for dark matter.Event vertex and event time are not only useful for event selectio... Large-volume liquid scintillator detectors with ultra-low background levels have been widely used to study neutrino physics and search for dark matter.Event vertex and event time are not only useful for event selection but also essential for the reconstruction of event energy.In this study,four event vertex and event time reconstruction algorithms using charge and time information collected by photomultiplier tubes were analyzed comprehensively.The effects of photomultiplier tube properties were also investigated.The results indicate that the transit time spread is the main effect degrading the vertex reconstruction,while the effect of dark noise is limited.In addition,when the event is close to the detector boundary,the charge information provides better performance for vertex reconstruction than the time information. 展开更多
关键词 JUNO Liquid scintillator detector Neutrino experiment vertex reconstruction Time reconstruction
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Vertex-distinguishing E-total Coloring of Complete Bipartite Graph K 7,n when7≤n≤95 被引量:14
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作者 chen xiang-en du xian-kun 《Communications in Mathematical Research》 CSCD 2016年第4期359-374,共16页
Let G be a simple graph. A total coloring f of G is called an E-total coloring if no two adjacent vertices of G receive the same color, and no edge of G receives the same color as one of its endpoints.... Let G be a simple graph. A total coloring f of G is called an E-total coloring if no two adjacent vertices of G receive the same color, and no edge of G receives the same color as one of its endpoints. For an E-total coloring f of a graph G and any vertex x of G, let C(x) denote the set of colors of vertex x and of the edges incident with x, we call C(x) the color set of x. If C(u) ≠ C(v) for any two different vertices u and v of V (G), then we say that f is a vertex-distinguishing E-total coloring of G or a VDET coloring of G for short. The minimum number of colors required for a VDET coloring of G is denoted by Хvt^e(G) and is called the VDE T chromatic number of G. The VDET coloring of complete bipartite graph K7,n (7 ≤ n ≤ 95) is discussed in this paper and the VDET chromatic number of K7,n (7 ≤ n ≤ 95) has been obtained. 展开更多
关键词 GRAPH complete bipartite graph E-total coloring vertex-distinguishingE-total coloring vertex-distinguishing E-total chromatic number
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Vertex solution theorem for the upper and lower bounds on the dynamic response of structures with uncertain-but-bounded parameters 被引量:5
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作者 Zhiping Qiu Xiaojun Wang Institute of Solid Mechanics, Beihang University, 100083 Beijing, China 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第3期367-379,共13页
The aim of this paper is to evaluate the effects of uncertain-but-bounded parameters on the dynamic response of structures. By combining the interval mathematics and the finite element analysis, the mass matrix, dampi... The aim of this paper is to evaluate the effects of uncertain-but-bounded parameters on the dynamic response of structures. By combining the interval mathematics and the finite element analysis, the mass matrix, damping matrix, stiffness matrix and the external loads are represented as interval matrices and vector. With the help of the optimization theory, we present the vertex solution theorem for determining both the exact upper bounds or maximum values and the exact lower bounds or minimum values of the dynamic response of structures, in which these parameters reach their extreme values on the boundary of the interval mass, damping, stiffness matrices and the interval extemal loads vector. Three examples are used to illustrate the computational aspects of the presented vertex solution theorem. 展开更多
关键词 Dynamic response vertex solution theorem Uncertain-but-bounded parameters
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A POLYNOMIAL ALGORITHM FOR FINDING THEMINIMUM FEEDBACK VERTEX SET OF A3-REGULAR SIMPLE GRAPH 被引量:2
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作者 李德明 刘彦佩 《Acta Mathematica Scientia》 SCIE CSCD 1999年第4期375-381,共7页
A subset of the vertex set of a graph is a feedback vertex set of the graph if the resulting graph is a forest after removed the vertex subset from the graph. A polynomial algorithm for finding a minimum feedback vert... A subset of the vertex set of a graph is a feedback vertex set of the graph if the resulting graph is a forest after removed the vertex subset from the graph. A polynomial algorithm for finding a minimum feedback vertex set of a 3-regular simple graph is provided. 展开更多
关键词 maximum genus nonseparating independent number feedback vertex set 3-regular graph adjacency matching
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Improvement of machine learning-based vertex reconstruction for large liquid scintillator detectors with multiple types of PMTs 被引量:3
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作者 Zi-Yuan Li Zhen Qian +6 位作者 Jie-Han He Wei He Cheng-Xin Wu Xun-Ye Cai Zheng-Yun You Yu-Mei Zhang Wu-Ming Luo 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第7期93-102,共10页
The precise vertex reconstruction for large liquid scintillator detectors is essential.A novel machine learning-based method was successfully developed to reconstruct an event vertex in JUNO.In this study,the performa... The precise vertex reconstruction for large liquid scintillator detectors is essential.A novel machine learning-based method was successfully developed to reconstruct an event vertex in JUNO.In this study,the performance of machine learning-based vertex reconstruction was further improved by optimizing the input images of neural networks.By separating the information of different types of PMTs and adding the information of the second hit of PMTs,the vertex resolution was improved by approximately 9.4% at 1 MeV and 9.8% at 11 MeV. 展开更多
关键词 JUNO Liquid scintillator detector Neutrino experiment vertex reconstruction Machine learning
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Vertex degree autocorrelation topological index and its application in QSAR study of organic chemicals 被引量:2
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作者 王鹏 杨蕾 +1 位作者 高大文 龙明策 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2001年第4期394-398,共5页
Considering the calculated result and higher degeneracy existing in the calculation of autocorrelation topological index totally depend on experimental parameters, a new group of autocorrelation topological index as ... Considering the calculated result and higher degeneracy existing in the calculation of autocorrelation topological index totally depend on experimental parameters, a new group of autocorrelation topological index as A t, B t, C t and D t was designed and developed based on the vertex degree of molecular topology and autocorrelation function of mathematics. Autocorrelation function f(i) was calculated from the square root of the vertex degree, revised vertex degree and their combination, and they are (δ i) 1/2 , (δ V i) 1/2 ,(δ V i+δ i) 1/2  and (δ E i-δ i) 1/2 / N. With the matrix description method achieved, and the unit input in matrix of unsaturated bond and heteroatoms revised based on the adjacency matrix and distance matrix of organic molecular graph, the corresponding computer software has also been designed and developed. Better results have been obtained for the application of these indexes in QSAR study of organic chemicals. 展开更多
关键词 topological index vertex degree autocorrelation function QSAR molecular topology
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