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Independence Polynomials and the Merrifield-Simmons Index of Mono-Layer Cylindrical Grid Graphs
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作者 JI Lin-xing ZHANG Ke HU Wen-jun 《Chinese Quarterly Journal of Mathematics》 2024年第4期379-387,共9页
Research on the independence polynomial of graphs has been very active.However,the computational complexity of determining independence polynomials for general graphs remains NP-hard.Letα(G)be the independence number... Research on the independence polynomial of graphs has been very active.However,the computational complexity of determining independence polynomials for general graphs remains NP-hard.Letα(G)be the independence number of G and i(G;k)be the number of independent sets of order k in G,then the independence polynomial is defined as I(G;x)=∑_(k=0)^(α(G))i(G;k)x^(k),i(G;0)=1.In this paper,by utilizing the transfer matrix,we obtain an analytical expression for I(CGn;x)of mono-cylindrical grid graphs CGn and present a crucial proof of it.Moreover,we also explore the Merrifield-Simmons index and other properties of CGn. 展开更多
关键词 Independence polynomial Cylindrical grid graphs Transfer matrix merrifield-simmons index
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Extremal Problem with Respect to Merrifield-Simmons Index and Hosoya Index of a Class of Polygonal Chains
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作者 TIAN Wenwen TIAN Shuangliang +1 位作者 HE Xue WANG Yanfeng 《Wuhan University Journal of Natural Sciences》 CAS 2014年第4期295-300,共6页
The Merrifield-Simmons index of a graph is defined as the total number of the independent sets of the graph and the Ho- soya index of a graph is defined as the total number of the match- ings of the graph. In this pap... The Merrifield-Simmons index of a graph is defined as the total number of the independent sets of the graph and the Ho- soya index of a graph is defined as the total number of the match- ings of the graph. In this paper, the definition of a class of po- lygonal chains is given, ordering of the polygonal chains with respect to Merrifield-Simmons index and Hosoya index are ob- tained, and their extremal graphs with respect to these two topo- logical indices are determined. 展开更多
关键词 merrifield-simmons index Hosoya index ordering:extremal graph
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ON THE ORDERING OF A CLASS OF HEXAGONAL CHAINS WITH RESPECT TO MERRIFIELD-SIMMONS INDEX 被引量:1
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作者 ZHANG Lianzhu (Department of Mathematics, Zhangzhou Teachers College, Zhangzhou, Fujian 363000, China) 《Systems Science and Mathematical Sciences》 SCIE EI CSCD 2000年第2期219-224,共6页
In this paper, we give the ordering of single-corner hexagonal chains with respect to Merrifield-Simmons index. At the same time, the hexagonal chain with the second largest Merrifield-Simmons index is also determined.
关键词 HEXAGONAL system HEXAGONAL CHAIN single-corner CHAIN linear CHAIN independent set merrifield-simmons index.
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Vulnerability assessment in fractured aquifer using improved vulnerability index:Applied to Gabes aquifer,Southeastern Tunisia
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作者 Mounir Atoui Belgacem Agoubi 《Journal of Groundwater Science and Engineering》 2026年第1期69-82,共14页
The Gabes aquifer system,located in southeastern Tunisia,is a crucial resource for supporting local socio-economic activities.Due to its dual porosity structure,is particularly vulnerable to pollution.This study aims ... The Gabes aquifer system,located in southeastern Tunisia,is a crucial resource for supporting local socio-economic activities.Due to its dual porosity structure,is particularly vulnerable to pollution.This study aims to develop a hybrid model that combines the Fracture Aquifer Index(FAI)with the conventional GOD(Groundwater occurrence,Overall lithology,Depth to water table)method,to assess groundwater vulnerability in fractured aquifer.To develop the hybrid model,the classical GOD method was integrated with FAI to produce a single composite index.Each parameter within both GOD and FAI was scored,and a final index was calculated to delineate vulnerable areas.The results show that the study area can be classified into four vulnerability levels:Very low,low,moderate,and high,indicating that approximately 8%of the area exhibits very low vulnerability,29%has low vulnerability,25%falls into the moderate category,and 38%is considered highly vulnerable.The FAI-GOD model further incorporates fracture network characteristics.This refinement reduces the classification to three vulnerability classes:Low,medium,and high.The outcomes demonstrate that 46%of the area is highly vulnerable due to a dense concentration of fractures,while 17%represents an intermediate zone characterized by either shallow or deeper fractures.In contrast,37%corresponds to areas with lightly fractured rock,where the impact on vulnerability is minimal.Multivariate statistical analysis was employed using Principal Components Analysis(PCA)and Hierarchical Cluster Analysis(HCA)on 24 samples across six variables.The first three components account for over 76%of the total variance,reinforcing the significance of fracture dynamics in classifying vulnerability levels.The FAI-GOD model removes the very-low-vulnerability class and expands the spatial extent of low-and high-vulnerability zones,reflecting the dominant influence of fracture networks on aquifer sensitivity.While both indices use a five-class system,FAI-GOD redistributes vulnerability by eliminating very-low-vulnerability areas and amplifying low/high categories,highlighting the critical role of fractures.A strong correlation(R2=0.94)between the GOD and FAI-GOD indices,demonstrated through second-order polynomial regression,confirms the robustness of the FAI-GOD model in accurately predicting vulnerability to pollution.This model provides a useful framework for assessing the vulnerability of complex aquifers and serves as a decision-making tool for groundwater managers in similar areas. 展开更多
关键词 GROUNDWATER Aquifer vulnerability Fractured media FAI-GOD index GOD index GIS
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The triglyceride-glucose index shows promise as a novel prognostic marker for advanced hepatocellular carcinoma
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作者 Tao Xu Xu Qi +1 位作者 Fei-Yu Zhao Nian-Song Qian 《World Journal of Gastroenterology》 2026年第2期167-169,共3页
This commentary critically appraises the study by Li et al which pioneered the exploration of the triglyceride-glucose(TyG)index as a prognostic marker in hepatitis B virus-related advanced hepatocellular carcinoma pa... This commentary critically appraises the study by Li et al which pioneered the exploration of the triglyceride-glucose(TyG)index as a prognostic marker in hepatitis B virus-related advanced hepatocellular carcinoma patients undergoing combined camrelizumab and lenvatinib therapy.While we acknowledge the study’s clinical relevance in proposing an easily accessible metabolic biomarker,we delve into the mechanistic plausibility linking insulin resistance to immunotherapy response and angiogenic inhibition.We further critically examine the methodological limitations,including the retrospective design,the populationspecific TyG cut-off value,and unaddressed metabolic confounders.We highlight the imperative for future research to validate its utility across diverse etiologies and treatment settings,and to unravel the underlying immunometabolic pathways. 展开更多
关键词 Triglyceride-glucose index Prognostic marker Advanced hepatocellular carcinoma Camrelizumab Lenvatinib
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Construction of a mental health literacy evaluation index system for adolescents with mental disorders
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作者 Ying-Qiong Ge Xiao-Shuang Ouyang +2 位作者 Zheng-Min Zhu Bi-Can Tan Xiao-Jian Jiang 《World Journal of Psychiatry》 2026年第1期299-311,共13页
BACKGROUND Timely and accurate evaluation of mental disorders in adolescents using appropriate mental health literacy assessment tools is essential for improving their mental health literacy levels.AIM To develop an e... BACKGROUND Timely and accurate evaluation of mental disorders in adolescents using appropriate mental health literacy assessment tools is essential for improving their mental health literacy levels.AIM To develop an evaluation index system for the mental health literacy of adolescent patients with mental disorders,providing a scientific,comprehensive,and reliable tool for the monitoring and intervention of mental health literacy of such patients.METHODS From December 2022 to June 2023,the evaluation index system for mental health literacy of adolescents with mental disorders was developed through literature reviews,semi-structured interviews,expert letter consultations,and the analytic hierarchy process.Based on this index system,a self-assessment questionnaire was compiled and administered to 305 adolescents with mental disorders to test the reliability and validity of the index system.RESULTS The final evaluation index system for mental health literacy of adolescents with mental disorders included 4 first-level indicators,10 second-level indicators,and 52 third-level indicators.The overall Cronbach’sαcoefficient of the index system was 0.957,with a partial reliability of 0.826 and a content validity index of 0.975.The cumulative variance contribution rate of 10 common factors was 66.491%.The correlation coefficients between each dimension and the total questionnaire ranged from 0.672 to 0.724,while the correlation coefficients in each dimension ranged from 0.389 to 0.705.CONCLUSION The evaluation index system for mental health literacy of adolescents with mental disorders,developed in this study,demonstrated notable reliability and validity,making it a valuable tool for evaluating mental health literacy in this population. 展开更多
关键词 Adolescents Mental disorders Mental health literacy Evaluation index system Delphi method
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似星树依Merrifield-Simmons指数的排序 被引量:3
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作者 吴继春 邓汉元 姜琴 《晓庄学院自然科学学报》 CAS 北大核心 2008年第3期30-33,共4页
设i(G)是图G的Merrifield-Simmons指数.对图G1和G2,若i(G1)<i(G2),则记G1<G2.只有一个顶点的度≥2的树称为似星树.对具有不同分枝的似星树的Merrifield-Simmons指数进行了比较,对具有相同分枝的似星树的Merrifield-Simmons指数进... 设i(G)是图G的Merrifield-Simmons指数.对图G1和G2,若i(G1)<i(G2),则记G1<G2.只有一个顶点的度≥2的树称为似星树.对具有不同分枝的似星树的Merrifield-Simmons指数进行了比较,对具有相同分枝的似星树的Merrifield-Simmons指数进行了排序;并利用"<"关系,刻画出了似星树关于Merrifield-Simmons指数的极图. 展开更多
关键词 似星树 merrifield-simmons指数 排序 极图
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关于多边形螺环链的Merrifield-Simmons指标极值的研究 被引量:2
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作者 陈香莲 李硕 《山东大学学报(理学版)》 CAS CSCD 北大核心 2012年第12期47-52,63,共7页
给出了多边形螺环链的定义,研究了多边形螺环链关于Merrifield-Simmons指标的极值问题,得到了多边形螺环链关于Merrifield-Simmons指标的排序。
关键词 多边形螺环链 merrifield-simmons指标 极值 排序
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一类特殊图关于Merrifield-Simmons指标和Hosoya指标的排序 被引量:1
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作者 田文文 田双亮 郭敏 《黑龙江大学自然科学学报》 CAS 北大核心 2015年第1期58-62,共5页
Merrifield-Simmons指标和Hosoya指标是化学图论中两个重要的拓扑指标。图的Merrifield-Simmons指标定义为该图中所有独立集数目的和,图的Hosoya指标定义为该图中所有匹配数目的和。研究一类图Gk的Merrifield-Simmons指标和Hosoya指标,... Merrifield-Simmons指标和Hosoya指标是化学图论中两个重要的拓扑指标。图的Merrifield-Simmons指标定义为该图中所有独立集数目的和,图的Hosoya指标定义为该图中所有匹配数目的和。研究一类图Gk的Merrifield-Simmons指标和Hosoya指标,根据Cq上两接点u和v之间的距离,给出了该类图Gk关于这两种指标的排序。 展开更多
关键词 merrifield-simmons指标 HOSOYA指标 排序
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偶多边形联链的Merrifield-Simmons指标的极值 被引量:1
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作者 陈香莲 白亚丽 苏贵福 《陕西师范大学学报(自然科学版)》 CAS CSCD 北大核心 2013年第2期19-23,共5页
对多联苯链的概念加以推广,给出偶多边形联链的概念,讨论了关于Merrifield-Simmons指标的极值问题.利用递归公式,将偶多边形联链按指数大小合理排序.证明了偶多边形联链ZN(2n)、SN(2n)分别获得Merrifield-Simmons指标的极小、极大值.
关键词 偶多边形联链 merrifield-simmons指标 极值
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N维超立方体的Merrifield-Simmons指标 被引量:3
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作者 盛集明 沈艳军 《兰州理工大学学报》 CAS 北大核心 2015年第5期163-166,共4页
Merrifield-Simmons指标定义为图G中包含空点集在内的独立集的总数.Merrifield-Simmons指标在分子化学中有着广泛的应用.利用超立方体与有限集的幂集的Hasse图之间的同构关系,研究n维超立方体的MerrifieldSimmons指标.当k≦5时,得到k-... Merrifield-Simmons指标定义为图G中包含空点集在内的独立集的总数.Merrifield-Simmons指标在分子化学中有着广泛的应用.利用超立方体与有限集的幂集的Hasse图之间的同构关系,研究n维超立方体的MerrifieldSimmons指标.当k≦5时,得到k-独立集的指标序列. 展开更多
关键词 merrifield-simmons指标 独立集 n维超立方体 Hasse图
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一类特殊三圈图关于Merrifield-Simmons指标和Hosoya指标的排序 被引量:1
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作者 田文文 田双亮 《宁夏大学学报(自然科学版)》 CAS 2014年第3期212-215,共4页
研究了一类三圈图Tk的Merrifield-Simmons指标和Hosoya指标,根据Cq上2接点u和v之间的距离,给出了该类三圈图关于这2种指标的排序.
关键词 三圈图 merrifield-simmons指标 HOSOYA指标 排序
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聚苯链Merrifield-Simmons指标的计算 被引量:1
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作者 周旭冉 王力工 《纺织高校基础科学学报》 CAS 2011年第2期238-242,共5页
Merrifield-Simmons指标是化学分子图论研究中较为流行和重要的拓扑指标之一.为了方便,快速地计算出聚苯链的Merrifield-Simmons指标,采用递推法得到了3种特殊聚苯链Zn,Sn和Ln的Merrifield-Simmons指标的计算公式,经过一些矩阵运算后,... Merrifield-Simmons指标是化学分子图论研究中较为流行和重要的拓扑指标之一.为了方便,快速地计算出聚苯链的Merrifield-Simmons指标,采用递推法得到了3种特殊聚苯链Zn,Sn和Ln的Merrifield-Simmons指标的计算公式,经过一些矩阵运算后,得到了这3种聚苯链的Merri-field-Simmons指标的更为一般的计算公式. 展开更多
关键词 聚苯链 merrifield-simmons指标 递推公式
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关于Hosoya指标和Merrifield-Simmons指标的k色极图 被引量:2
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作者 许克祥 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2010年第3期312-315,共4页
图的Hosoya指标定义为图中包含空边集在内的对集总数.图的Merrifield-Simmons指标定义为图中包含空点集在内的点独立集总数.考虑点数为n的k色连通图的集合Gn,k,证明了Tur n图Tn(k)是Gn,k中Hosoya指标最大且Merrifield-Simmons指标最小的... 图的Hosoya指标定义为图中包含空边集在内的对集总数.图的Merrifield-Simmons指标定义为图中包含空点集在内的点独立集总数.考虑点数为n的k色连通图的集合Gn,k,证明了Tur n图Tn(k)是Gn,k中Hosoya指标最大且Merrifield-Simmons指标最小的图,还确定了k=2,3时Gn,k中Hosoya指标最小且Merrifield-Simmons指标最大的图. 展开更多
关键词 HOSOYA指标 merrifield-simmons指标 色数
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有确定悬挂点数的树的Merrifield-Simmons指标的极小值 被引量:2
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作者 张淑敏 《信阳师范学院学报(自然科学版)》 CAS 2010年第3期340-342,共3页
刻画了具有次小、第三小Merrifield-Simmons指标的4叶树.具有r个悬挂点的树称为r叶树,所讨论的图均为简单和有限的无向图.
关键词 merrifield-simmons指标 r叶树 极值
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四角链的Merrifield-Simmons指标 被引量:2
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作者 田文文 田双亮 《山东理工大学学报(自然科学版)》 CAS 2013年第3期6-10,共5页
四角链是由若干个单位正方形序列且任意相邻两个正方形之间只有一条割边构成的连通图.研究了n个单位正方形序列构成的四角链在两种不同构联接位下的Merrifield-Simmons指标,并给出了具体表达式.
关键词 四角链 merrifield-simmons指标 FIBONACCI数
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一类三圈图关于Merrifield-Simmons指标的排序 被引量:1
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作者 田文文 田双亮 王文婷 《鲁东大学学报(自然科学版)》 2014年第1期1-3,共3页
研究了一类三圈图T k的Merrifield-Simmons指标,根据C q上三种不同的连接方式,给出了该类三圈图关于Merrifield-Simmons指标的排序.
关键词 三圈图 merrifield-simmons指标 排序
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关于多联苯链的Merrifield-Simmons指标的研究 被引量:1
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作者 陈香莲 白亚丽 张艳玲 《伊犁师范学院学报(自然科学版)》 2012年第3期15-20,共6页
Merrifield-Simmons指标是化学分子图论研究中较为流行和重要的拓扑指标之一.主要通过对三个特殊多联苯链Zn,Sn和Ln的Merrifield-Simmons指标的研究,给出了一般多联苯链的Merrifield-Simmons指标计算公式,是对文献[1]关于多联苯链的Merr... Merrifield-Simmons指标是化学分子图论研究中较为流行和重要的拓扑指标之一.主要通过对三个特殊多联苯链Zn,Sn和Ln的Merrifield-Simmons指标的研究,给出了一般多联苯链的Merrifield-Simmons指标计算公式,是对文献[1]关于多联苯链的Merrifield-Simmons指标研究的补充. 展开更多
关键词 多联苯链 merrifield-simmons指标 路径
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圈链的Merrifield-Simmons指标和Hosoya指标
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作者 田文文 田双亮 何雪 《西北师范大学学报(自然科学版)》 CAS 北大核心 2014年第4期25-30,共6页
圈链是一类由若干个n阶圈构成的平面连通图.构造了两类特殊的圈链,并且研究了这两类圈链在不同构联接位下的Merrifield-Simmons指标和Hosoya指标,给出了相应的递推公式.
关键词 圈链 merrifield-simmons指标 HOSOYA指标
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棒棒糖图的Merrifield-Simmons和Hosoya指数 被引量:7
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作者 陈暑波 夏方礼 +1 位作者 龙韬 李俊峰 《湖南城市学院学报(自然科学版)》 CAS 2008年第3期39-41,共3页
i(G)表示图G的Merrifield-Simmons指数,定义为图G的独立点集个数;z(G)表示图G的Hosoya指数,m(G,k)表示G的k-匹配数,则z(G)是所有的m(G,k)的总和(1≤k≤[n/2]),其中n是G的顶点数.给出n阶棒棒糖图Ln,k的Merrifield-Simmons指数和Hosoya指... i(G)表示图G的Merrifield-Simmons指数,定义为图G的独立点集个数;z(G)表示图G的Hosoya指数,m(G,k)表示G的k-匹配数,则z(G)是所有的m(G,k)的总和(1≤k≤[n/2]),其中n是G的顶点数.给出n阶棒棒糖图Ln,k的Merrifield-Simmons指数和Hosoya指数以及它关于Merrifield-Simmons指数和Hosoya指数的一个排序. 展开更多
关键词 Merrifield—Siimmons指数 HOSOYA指数 棒棒糖图
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