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Total coloring of graphs embedded in surfaces of nonnegative Euler characteristic

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Science China Mathematics 2014年第1期57卷 211-220页

作者： WANG HuiJuan LIU Bin wu jianliang WANG Bing School of Mathematics Shandong University Department of Mathematics Ocean University of China Department of Mathematics Zaozhuang University

Let G be a graph which can be embedded in a surface of nonnegative Euler *** this paper,it is proved that the total chromatic number of G is △(G)+1 if △(G)9,where △(G)is the maximum degree of G.

关键词： total coloring,Euler characteristic,surface

Acyclic edge colorings of planar graphs and series-parallel graphs

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Science China Mathematics 2009年第3期52卷 605-616页

作者： HOU JianFeng wu jianliang LIU GuiZhen LIU Bin Department of Mathematics Shandong UniversityJinan 250100China

A proper edge coloring of a graph G is called acyclic if there is no 2-colored cycle in G. The acyclic edge chromatic number of G, denoted by a (G), is the least number of colors in an acyclic edge coloring of G. Alon et al. conjectured that a (G) Δ(G) + 2 for any graphs. For planar graphs G with girth g(G), we prove that a (G) max{2Δ(G) + 2, Δ(G) + 22} if g(G) 3, a (G) Δ(G) + 2 if g(G) 5, a (G) Δ(G) + 1 if g(G) 7, and a (G) = Δ(G) if g(G) 16 and Δ(G) 3. For series-parallel graphs G, we have a (G) Δ(G) + 1.

关键词： acyclic coloring planar graph girth series-parallel graph 05C15

河北省廊坊市文安县湿地公园建设现状及保护措施初探

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天津农林科技 2024年第4期 43-46页

作者：宋丽艳吴建梁刘佳荣文安县自然资源和规划局河北廊坊065800 天津市规划和自然资源局林业事务中心天津300000

为加强湿地保护,维护湿地生态、经济和社会功能,促进湿地资源可持续利用,文章对河北省廊坊市文安县赵王新河湿地公园建设和保护措施进行了初步探索,概述了湿地公园资源现状、生物多样性、主要生态特征等,对湿地公园建设及保护利用措施... 详细信息

为加强湿地保护,维护湿地生态、经济和社会功能,促进湿地资源可持续利用,文章对河北省廊坊市文安县赵王新河湿地公园建设和保护措施进行了初步探索,概述了湿地公园资源现状、生物多样性、主要生态特征等,对湿地公园建设及保护利用措施提出了可行性建议,为增强湿地公园的生态功能、保障当地生态安全提供参考。

关键词：赵王新河湿地公园生物多样性保护措施

Modularized and Parametric Modeling Technology for Finite Element Simulations of Underground Engineering under Complicated Geological Conditions

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 621-645页

作者： Jiaqi wu Li Zhuo jianliang Pei Yao Li Hongqiang Xie Jiaming wu Huaizhong Liu State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China Research Institute of Testing and Inspection Sinohydro Bureau 7 Co.Ltd.Chengdu610213China

The surrounding geological conditions and supporting structures of underground engineering are often updated during construction,and these updates require repeated numerical *** improve the numerical modeling efficiency of underground engineering,a modularized and parametric modeling cloud server is developed by using Python *** basic framework of the cloud server is as follows:input the modeling parameters into the web platform,implement Rhino software and FLAC3D software to model and run simulations in the cloud server,and return the simulation results to the web *** modeling program can automatically generate instructions that can run the modeling process in Rhino based on the input modeling *** main modules of the modeling program include modeling the 3D geological structures,the underground engineering structures,and the supporting structures as well as meshing the geometric *** particular,various cross-sections of underground caverns are crafted as parametricmodules in themodeling *** and parametric modeling program is used for a finite element simulation of the underground powerhouse of the Shuangjiangkou Hydropower *** complicatedmodel is rapidly generated for the simulation,and the simulation results are ***,this modularized and parametric modeling program is applicable for three-dimensional finite element simulations and analyses.

关键词： Underground engineering modularized and parametric modeling finite element method complex geological structure cloud modeling

法系大白猪繁殖性状遗传参数估计及遗传进展分析

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畜牧兽医学报 2024年第6期55卷 2388-2396页

作者：闫田田武建亮王朝军徐利孟庆利苏美玉李涵乔黄国英王超林佳琪北京中育种猪有限责任公司北京100194

旨在对北京市某母猪场法系大白猪繁殖性状进行遗传参数估计,评估其遗传进展,为该育种场制定合理的育种方案提供理论依据。本研究共收集北京市某母猪场2016-2022年法系大白母猪原始配种记录29 269条,原始分娩记录20 770条,原始系谱记录14... 详细信息

旨在对北京市某母猪场法系大白猪繁殖性状进行遗传参数估计,评估其遗传进展,为该育种场制定合理的育种方案提供理论依据。本研究共收集北京市某母猪场2016-2022年法系大白母猪原始配种记录29 269条,原始分娩记录20 770条,原始系谱记录146 871条,估计该公司法系大白母猪繁殖性状的遗传参数,采用基于动物模型的最佳线性无偏预测(best linear unbiased prediction, BLUP)方法,利用DMU软件使用单性状和双性状重复力模型进行遗传力、遗传相关、表型相关和育种值的估计。结果显示,本研究中法系大白猪TNB为12.67头,NBA为10.90头,NSB为1.35头,MUM为0.14头,LWT为13.99 kg, LW21为73.93 kg;繁殖性状遗传力估计值范围为0.017~0.134,属于低遗传力;繁殖性状间的遗传相关在-0.368~0.856之间,表型相关在-0.213~0.847之间;通过绘制繁殖性状表型趋势图及遗传趋势图发现,个体的繁殖性状表型值呈上升趋势,育种值呈先上升后下降趋势。本研究结果表明,该群体遗传改良取得了良好的进展,研究结果可为法系大白猪的品种选育和遗传改良提供参考指导和理论基础。

关键词：大白猪繁殖性能遗传参数估计遗传趋势

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Edge Colorings of Planar Graphs without 6-Cycles with Two Chords

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Open Journal of Discrete Mathematics 2013年第2期3卷 83-85页

作者： Ling Xue jianliang wu Department of Information Engineering Taishan Polytechnic Tai’an China School of Mathematics Shandong University Jinan China

It is proved here that if a planar graph has maximum degree at least 6 and any 6-cycle contains at most one chord, then it is of class 1.

关键词： Edge Coloring Planar Graph Cycle Class 1

THE LINEAR ARBORICITY OF COMPOSITION GRAPHS

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Journal of Systems Science & Complexity 2002年第4期15卷 372-375页

作者： wu jianliang LIU Guizhen Yuliang Department of Economics Shandong University

The linear arboricity la(G) of a graph G is the minimum number of linear forests which partition the edges of G. Akiyama, Exoo and Harary conjectured that la(G) = [△(G)+1/2] for any regular graph G. In this paper, we... 详细信息

关键词： Graph composition of graphs linear arboricity complete multipartite graph.

基于LiDAR点云的大型垃圾填埋场数字高程模型建模方法研究

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环境工程 2024年第5期42卷 192-198页

作者：张效刚胡良军宋树祥吴建良杜永潇杨军李耀晃陈晓强广州环投环境服务有限公司广州510540 广州市市政工程试验检测有限公司广州510520

为解决无人机巡检应用于生活垃圾填埋场堆体稳定性监测的技术难点,以国内华南地区最大的兴丰垃圾填埋场为研究对象,对其进行点云数据采集,采用径向基函数、最近邻域、不规则三角网、反距离加权方法4种方法建立数字高程模型,并通过对堆... 详细信息

为解决无人机巡检应用于生活垃圾填埋场堆体稳定性监测的技术难点,以国内华南地区最大的兴丰垃圾填埋场为研究对象,对其进行点云数据采集,采用径向基函数、最近邻域、不规则三角网、反距离加权方法4种方法建立数字高程模型,并通过对堆体阴影图、地形相关性、等高线图、最大排水长度图的模型参数分析,比选适宜于垃圾填埋场的点云采集与建模方法。结果表明:垃圾填埋场表面覆盖有反射方向性强的树脂类覆膜,对激光雷达射线的反射有明显的方向性,对无人机的可测试范围有较强的抑制作用。50 m航线高度下,需要航线间隔≤60 m才可保障高于100点/m^(2)的数据采集量。在覆膜坡度较大区域,需布置单独的航线。比对建模及应用效果可知:不规则三角网方法综合性能最佳,地形高程精度偏差≤2 cm,可以较好地应对地形等高线绘制、流水流迹模拟等任务。

关键词：无人机航空激光雷达点云数字高程模型不规则三角网

Total coloring of embedded graphs of maximum degree at least ten

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Science China Mathematics 2010年第8期53卷 2127-2133页

作者： HOU JianFeng 1,2,wu jianliang 2,LIU GuiZhen 2 & LIU Bin 2 1 Center for Discrete Mathematics,Fuzhou University,Fuzhou 350002,China 2 School of Mathematics,Shandong University,Jinan 250100,China Center for Discrete Mathematics Fuzhou University Fuzhou China School of Mathematics Shandong University Jinan China

A total k-coloring of a graph G is a coloring of V(G) ∪ E(G) using k colors such that no two adjacent or incident elements receive the same *** total chromatic number χ〃(G) is the smallest integer k such that G has a total *** this paper,it is proved that the total chromatic number of any graph G embedded in a surface Σ of Euler characteristic χ(Σ)≥0 is Δ(G) + 1 if Δ(G)≥10,where Δ(G) denotes the maximum degree of G.

关键词： surface Euler characteristic total coloring total chromatic number