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四面体表面上的正则曲线
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作者 雷逢春 尹逊波 《吉林大学自然科学学报》 CAS CSCD 北大核心 2001年第2期10-12,共3页
给出四面体表面上正则曲线的长度特征 .
关键词 四面体 正则曲线 长度 正则弧 数学归纳法 交点数
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An Oracle-based Data Management Method for Large Database in CyberCity GIS 被引量:4
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作者 ZHUQing HUANGDuo +1 位作者 YAOXuefeng ZHANGYeting 《Geo-Spatial Information Science》 2003年第4期39-43,共5页
An Oracle8i-based approach is proposed to manage the integrated databases oflarge CyberCity. This approach consists of three schemes: ① a special R+-tree index is designed toaccelerate spatial retrieving, in which th... An Oracle8i-based approach is proposed to manage the integrated databases oflarge CyberCity. This approach consists of three schemes: ① a special R+-tree index is designed toaccelerate spatial retrieving, in which the bounding boxes of local regions have no intersection andall leaf nodes of the R+-tree (geometry records ) have no repetition; ② different data compressionalgorithms are adopted to compress the digital elevation models, 3D vector models and images, suchas LZ77 lossless compression algorithm for compression of vector data and JPEG compressionalgorithms for texture images; ③ in order to communicate with Oracle8i database, a CyberCity GIS.spatial database engine (SDE) is designed. On the basis of this SDE prototype a case study is done. 展开更多
关键词 CyberCity spatial database engine R+-trees Oracle8i database
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Analysis of digenic epistatic effects and QE interaction effects QTL controlling grain weight in rice 被引量:11
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作者 高用明 朱军 +3 位作者 宋佑胜 何慈信 石春海 邢永忠 《Journal of Zhejiang University Science》 EI CSCD 2004年第4期371-377,共7页
Immortalized F2 population of rice (Oryza sativa L.) was developed by randomly mating F1 among recombinant inbred (RI) lines derived from (Zhenshan 97B×Minghui 63),which allowed replications within and across env... Immortalized F2 population of rice (Oryza sativa L.) was developed by randomly mating F1 among recombinant inbred (RI) lines derived from (Zhenshan 97B×Minghui 63),which allowed replications within and across environments.QTL (quantitative trait loci) mapping analysis on kilo-grain weight of immortalized F2 population was performed by using newly developed software for QTL mapping,QTL Mapper 2.0. Eleven distinctly digenic epistatic loci included a total of 15 QTL were located on eight chromosomes.QTL main effects of additive,dominance,and additive×additive,additive×dominance,and dominance×dominance interactions were estimated.Interaction effects between QTL main effects and environments (QE) were predicted.Less than 40% of single effects,most of which were additive effects,for identified QTL were significant at 5% level.The directional difference for QTL main effects suggested that these QTL were distributed in parents in the repulsion phase.This should make it feasible to improve kilo-grain weight of both parents by selecting appropriate new recombinants. Only few of the QE interaction effects were significant.Application prospect for QTL mapping achievements in genetic breeding was discussed. 展开更多
关键词 Immortalized F_2 population RICE Kilo-grain weight QTL EPISTASIS QTL×environment
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Thermal Quantum Discord in Anisotropic Heisenberg XXZ Model with Dzyaloshinskii-Moriya Interaction 被引量:3
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作者 陈一新 尹志 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第7期60-66,共7页
The thermal quantum discord (QD) is studied in a two-qubit Heisenberg XXZ system with DzyaloshinskiiMoriya (DM) interaction. We compare the thermal QD with thermal entanglement in this system and find remarkable d... The thermal quantum discord (QD) is studied in a two-qubit Heisenberg XXZ system with DzyaloshinskiiMoriya (DM) interaction. We compare the thermal QD with thermal entanglement in this system and find remarkable differences between them. For instance, we show situations where QD decreases asymptotically to zero with temperature T while entanglement decreases to zero at the point of critical temperature, situations where QD decreases with certain tunable parameters such as Dx and Dx when entanglement increases. We find that the characteristic of QD is exotic in this system and this possibly offers a potential solution to enhance entanglement of a system. We also show that tunable parameter Dx is more efficient than parameter Dz in most regions for controlling the QD. 展开更多
关键词 thermal quantum discord Heisenberg XXZ model Dzyaloshinskii-Moriya interaction
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Embedding Generalized Petersen Graph in Books 被引量:3
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作者 Bin ZHAO Wei XIONG +1 位作者 Yingzhi TIAN Jixiang MENG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2016年第3期385-394,共10页
A book embedding of a graph G consists of placing the vertices of G on a spine and assigning edges of the graph to pages so that edges in the same page do not cross each other. The page number is a measure of the qual... A book embedding of a graph G consists of placing the vertices of G on a spine and assigning edges of the graph to pages so that edges in the same page do not cross each other. The page number is a measure of the quality of a book embedding which is the minimum number of pages in which the graph G can be embedded. In this paper, the authors discuss the embedding of the generalized Petersen graph and determine that the page number of the generalized Petersen graph is three in some situations, which is best possible. 展开更多
关键词 Book embedding Page number Generalized Petersen graph
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Planar graphs with maximum degree 8 and without intersecting chordal 4-cycles are 9-totally colorable 被引量:5
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作者 CAI JianSheng WANG GuangHui YAN GuiYing 《Science China Mathematics》 SCIE 2012年第12期2601-2612,共12页
The minimum number of colors needed to properly color the vertices and edges of a graph G is called the total chromatic number of G and denoted by χ'' (G). It is shown that if a planar graph G has maximum deg... The minimum number of colors needed to properly color the vertices and edges of a graph G is called the total chromatic number of G and denoted by χ'' (G). It is shown that if a planar graph G has maximum degree Δ≥9, then χ'' (G) = Δ + 1. In this paper, we prove that if G is a planar graph with maximum degree 8 and without intersecting chordal 4-cycles, then χ ''(G) = 9. 展开更多
关键词 total coloring planar graph chordal 4-cycles TRIANGLES
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The Crossing Numbers of Cartesian Products of Stars with a 5-Vertex Graph
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作者 苏振华 黄元秋 《Journal of Mathematical Research and Exposition》 CSCD 2009年第4期580-586,共7页
In this paper, we compute the crossing number of a specific graph Hn, and then by contraction, we obtain the conclusion that cr(G13 × Sn) = 4[n/2] [n-1/2]+[n/2] . The result fills up the blank of the crossing ... In this paper, we compute the crossing number of a specific graph Hn, and then by contraction, we obtain the conclusion that cr(G13 × Sn) = 4[n/2] [n-1/2]+[n/2] . The result fills up the blank of the crossing numbers of Cartesian products of stars with all 5-vertex graphs presented by Marian Klesc. 展开更多
关键词 GRAPH DRAWING crossing number Cartesian products star.
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POLES OF ZETA FUNCTIONS OF COMPLETE INTERSECTIONS
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作者 WAN DAQING(Department of Mathematics, University of California, Irvine, CA 92697-3875, USA.) 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2000年第2期187-200,共14页
A vanishing theorem is proved for e-adic cohomology with compact support on an affine (singular) complete intersection. As an application, it is shown that for an affine complete intersection defined over a finite fie... A vanishing theorem is proved for e-adic cohomology with compact support on an affine (singular) complete intersection. As an application, it is shown that for an affine complete intersection defined over a finite field of q elements, the reciprocal "poles" of the zeta function are always divisible by q as algebraic integers. A p-adic proof is also given, which leads to further q-divisibiliy of the poles or equivalently an improvement of the polar part of the AxKatz theorem for an affine complete intersection. Similar results hold for a projective complete intersection. 展开更多
关键词 POLE Zeta function Complete intersection
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