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On Product-Cordial Index Sets and Friendly Index Sets of 2-Regular Graphs and Generalized Wheels 被引量:2
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作者 Harris KWONG Sin Min LEE Ho Kuen NG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2012年第4期661-674,共14页
A vertex labeling f : V →Z2 of a simple graph G = (V, E) induces two edge labelings The friendly index set and the product-cordial index set of G are defined as the setsf is friendly}. In this paper we study and d... A vertex labeling f : V →Z2 of a simple graph G = (V, E) induces two edge labelings The friendly index set and the product-cordial index set of G are defined as the setsf is friendly}. In this paper we study and determine the connection between the friendly index sets and product-cordial index sets of 2-regular graphs and generalized wheel graphs. 展开更多
关键词 Friendly index set product cordial index set 2-regular graphs generalized wheels
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Full Friendly Index Sets of Cartesian Products of Two Cycles 被引量:3
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作者 Wai chee SHIU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2010年第7期1233-1244,共12页
Let G =(V, E) be a connected simple graph. A labeling f : V → Z2 induces an edge labeling f* : E → Z2 defined by f*(xy) = f(x) +f(y) for each xy ∈ E. For i ∈ Z2, let vf(i) = |f^-1(i)| and ef(i... Let G =(V, E) be a connected simple graph. A labeling f : V → Z2 induces an edge labeling f* : E → Z2 defined by f*(xy) = f(x) +f(y) for each xy ∈ E. For i ∈ Z2, let vf(i) = |f^-1(i)| and ef(i) = |f*^-1(i)|. A labeling f is called friendly if |vf(1) - vf(0)| ≤ 1. For a friendly labeling f of a graph G, we define the friendly index of G under f by if(G) = e(1) - el(0). The set [if(G) | f is a friendly labeling of G} is called the full friendly index set of G, denoted by FFI(G). In this paper, we will determine the full friendly index set of every Cartesian product of two cycles. 展开更多
关键词 vertex labeling friendly labeling friendly index set Cartesian product of two cycles
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On Balance Index Set for the General Butterfly Graph 被引量:1
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作者 WEN YI Hui KANG Qing De 《Journal of Mathematical Research and Exposition》 CSCD 2009年第2期202-212,共11页
In this paper, we introduce the concept of the general butterfly graph B[m,n;d] for integers m,n ≥ 3, d ≥ 1, determine its balance index set, and give the necessary and sufficient condition for balanced graph B[m,n;... In this paper, we introduce the concept of the general butterfly graph B[m,n;d] for integers m,n ≥ 3, d ≥ 1, determine its balance index set, and give the necessary and sufficient condition for balanced graph B[m,n;d] to exist. 展开更多
关键词 friendly labeling balance labeling balance index set.
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Full friendly index sets of mCn
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作者 Yurong JI Jinmeng LIU +1 位作者 Yujie BAI Shufei WU 《Frontiers of Computer Science》 SCIE EI CSCD 2022年第3期95-99,共5页
Let G be a connected simple graph with vertex set V(G)and edge set E(G).A binary vertex labeling f:V(G)→Z2,is said to be friendly if the number of vertices with different labels differs by at most one.Each vertex fri... Let G be a connected simple graph with vertex set V(G)and edge set E(G).A binary vertex labeling f:V(G)→Z2,is said to be friendly if the number of vertices with different labels differs by at most one.Each vertex friendly labeling/induces an edge labeling f*E(G)→Z2,defined by f*(xy)=f(x)+f(y)for each xy∈E(G).Let er(i)=\{e∈E(G):f*(e)=i}|.The full friendly index set of G,denoted by FFI(G),is the set{ef*(1)-ep(0):f is friendly}.In this paper,we determine the full friendly index set of a family of cycle union graphs which are edge subdivisions of P2×Pn. 展开更多
关键词 vertex labeling friendly labeling full friendly index set PARTITION BISECTION
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Classification of the Index Sets of Low[n]~p and High [n]~p
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作者 眭跃飞 《Journal of Computer Science & Technology》 SCIE EI CSCD 1991年第3期285-290,共6页
In this paper we will first give the characterization of the p^-low p^-degree,and prove that a p.r.e. degree(?)contains a p^-speedable set A if and only if(?)′>P(?)′.Then we classify the index sets of Low[n]~p an... In this paper we will first give the characterization of the p^-low p^-degree,and prove that a p.r.e. degree(?)contains a p^-speedable set A if and only if(?)′>P(?)′.Then we classify the index sets of Low[n]~p and High[n]~p and prove that Low [n]~p is Σ~P[n+3]-complete and High [n]~p is Σ~P [n+4]-complete. 展开更多
关键词 Classification of the index sets of Low[n p and High
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基于Rosetta的粗糙集理论在糕点食品安全风险监测中的应用 被引量:3
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作者 张明 刘宏生 《食品安全质量检测学报》 CAS 2017年第11期4486-4490,共5页
目的以沈阳市2012~2015年糕点食品标准指标监测数据为研究对象,应用Rosetta粗糙集理论进行指标约简,挖掘各指标属性重要性,从而提出更加科学的指标风险监测方案。方法对数据合并分类整理,建立指数分级标准并离散数据生成决策表,使用遗... 目的以沈阳市2012~2015年糕点食品标准指标监测数据为研究对象,应用Rosetta粗糙集理论进行指标约简,挖掘各指标属性重要性,从而提出更加科学的指标风险监测方案。方法对数据合并分类整理,建立指数分级标准并离散数据生成决策表,使用遗传算法对数据进行约简。结果获得2组数据约简结果,确定核心指标为硫酸铝钾、糖精钠、山梨酸、柠檬黄、胭脂红、菌落总数、大肠菌群和霉菌计数。通过筛选得到18组指标决策规则,经分析硫酸铝钾和菌落总数为关键指标。在2组约简的不合格规则中,硫酸铝钾的覆盖度之和均为0.23,菌落总数分别为0.38和0.36,并且指数等级值均达到6级和7级,提示存在高风险。结论影响糕点食品质量安全的重要指标为硫酸铝钾、糖精钠、山梨酸、柠檬黄、胭脂红、菌落总数、大肠菌群和霉菌计数,建议至少1年监测2次,其中硫酸铝钾和菌落总数为关键监测指标,应给予高度重视,至少1年监测3次。其余指标影响较小,建议1年监测1次。 展开更多
关键词 粗糙集 糕点 食品安全标准 指标 约简
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基于dSFO-Set的可消除项集挖掘算法
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作者 谭龙 秦琦冰 《计算机工程与设计》 北大核心 2017年第6期1496-1502,共7页
为提高可消除项集的挖掘效率,在WPPC-Tree基础上提出优化后开始-结束序列树(start-finish-order tree,SFOTree),定义开始-结束序列集合(start-finish-order-set,SFO-Set)和开始-结束序列集合差(difference of start-finish-orderset,dSF... 为提高可消除项集的挖掘效率,在WPPC-Tree基础上提出优化后开始-结束序列树(start-finish-order tree,SFOTree),定义开始-结束序列集合(start-finish-order-set,SFO-Set)和开始-结束序列集合差(difference of start-finish-orderset,dSFO-Set),建立项集的收益索引,提出一种基于dSFO-Set的可消除项集挖掘算法。利用dSFO-Set性质和收益索引,提高项集收益的计算效率,减少可消除项集的挖掘代价。分别在稠密数据集和稀疏模拟数据集上与传统算法进行测试比较,实验结果表明,该算法具有更好的挖掘效率。 展开更多
关键词 可消除项集 开始-结束序列树 开始-结束序列集合差 收益索引
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城市地下空间综合效益评价的一种新方法——模糊(Fuzzy Set)评价模型 被引量:6
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作者 彭芳乐 侯学渊 陈立道 《地下空间》 CSCD 1991年第3期190-195,共6页
如何正确地评价城市地下空间综合效益是一个具有现实意义的课题。为了寻求城市地下空间综合效益评价方法及结果的统一性和实用性,本文针对综合评价指标中所出现的大量模糊性,在建立恰当的隶属函数基础上,对软、硬指标进行二级模糊评价运... 如何正确地评价城市地下空间综合效益是一个具有现实意义的课题。为了寻求城市地下空间综合效益评价方法及结果的统一性和实用性,本文针对综合评价指标中所出现的大量模糊性,在建立恰当的隶属函数基础上,对软、硬指标进行二级模糊评价运算,提出了一种较为符合实际的综合效益评价方法——模糊(Fuzzy Set)评价模型,并能在计算机上快速操作得出定量化评价结果。最后,本文还以沿海某大城市的已建人防工程综合效益评价作为考评对象,对模型的实际应用进行了验证。 展开更多
关键词 地下空间 模糊模型 城市 聚类分析
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基于Rough Sets理论的保障房项目后评价指标体系优化
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作者 王波 《土木工程与管理学报》 北大核心 2016年第4期68-75,共8页
保障性住房项目是社会保障体系的重要组成部分,关乎民生与社会和谐。首先对保障房项目后评价的主要内容和特点进行分析,采用改进型德尔菲法与HHM法,从项目目标、执行过程、项目影响、项目效益、项目可持续性等五个维度对保障房项目的后... 保障性住房项目是社会保障体系的重要组成部分,关乎民生与社会和谐。首先对保障房项目后评价的主要内容和特点进行分析,采用改进型德尔菲法与HHM法,从项目目标、执行过程、项目影响、项目效益、项目可持续性等五个维度对保障房项目的后评价指标进行识别与筛选。而后通过基于知识粒度与属性重要度的Rough Sets(粗糙集)理论对所有指标的重要度、指标权重、偏离程度进行计算,剔除与约简了偏离程度较大的冗余指标,建立起了更加科学合理的符合保障房项目固有特点的后评价指标体系,以期为以后的保障房项目后评价管理以及全寿命周期管理提供研究基础。 展开更多
关键词 保障房项目 后评价 指标体系优化 知识粒度 ROUGH setS理论
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Discrete Conley index and bifurcation points 被引量:1
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作者 王凯华 傅新楚 《Journal of Shanghai University(English Edition)》 CAS 2010年第6期400-404,共5页
In this paper, a sufficient condition for the existence of bifurcation points for discrete dynamical systems is presented. The relation between two families of systems is further discussed, and a sufficient condition ... In this paper, a sufficient condition for the existence of bifurcation points for discrete dynamical systems is presented. The relation between two families of systems is further discussed, and a sufficient condition for determining whether they may have the similar bifurcation points is given. 展开更多
关键词 discrete dynamical system prime isolated invariant set extreme maximal isolated invariant set Conley index bifurcation point
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Unsupervised Quick Reduct Algorithm Using Rough Set Theory 被引量:2
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作者 C. Velayutham K. Thangavel 《Journal of Electronic Science and Technology》 CAS 2011年第3期193-201,共9页
Feature selection (FS) is a process to select features which are more informative. It is one of the important steps in knowledge discovery. The problem is that not all features are important. Some of the features ma... Feature selection (FS) is a process to select features which are more informative. It is one of the important steps in knowledge discovery. The problem is that not all features are important. Some of the features may be redundant, and others may be irrelevant and noisy. The conventional supervised FS methods evaluate various feature subsets using an evaluation function or metric to select only those features which are related to the decision classes of the data under consideration. However, for many data mining applications, decision class labels are often unknown or incomplete, thus indicating the significance of unsupervised feature selection. However, in unsupervised learning, decision class labels are not provided. In this paper, we propose a new unsupervised quick reduct (QR) algorithm using rough set theory. The quality of the reduced data is measured by the classification performance and it is evaluated using WEKA classifier tool. The method is compared with existing supervised methods and the result demonstrates the efficiency of the proposed algorithm. 展开更多
关键词 index Terms--Data mining rough set supervised and unsupervised feature selection unsupervised quick reduct algorithm.
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基于集对-组合赋权的填埋场失稳风险评价方法 被引量:1
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作者 冯世进 徐熠 +2 位作者 杨俊毅 郑奇腾 张晓磊 《岩土力学》 EI CAS CSCD 北大核心 2024年第7期2129-2139,共11页
我国填埋场具有高水位、高气压的特征,现有规范和研究中虽提出了不同的稳定性评价指标和分级标准,但对指标权重和综合风险评估缺乏系统性研究。为此,建立了涵盖填埋场几何构型、垃圾土抗剪强度、液气赋存情况和降雨4类7个指标的填埋场... 我国填埋场具有高水位、高气压的特征,现有规范和研究中虽提出了不同的稳定性评价指标和分级标准,但对指标权重和综合风险评估缺乏系统性研究。为此,建立了涵盖填埋场几何构型、垃圾土抗剪强度、液气赋存情况和降雨4类7个指标的填埋场失稳风险评价指标体系,通过参数敏感性分析实现5级分类(稳定、较稳定、基本稳定、不稳定、极不稳定),并采用集对分析构建指标联系度函数。采用指标重要性排序法,通过参数敏感性分析、工程失稳事故、文献关注度统计和博弈论组合赋权,确定了评价指标的综合权重。最后,将指标综合权重与指标联系度函数耦合,建立了填埋场失稳风险综合评价模型,并应用于一实际填埋场工程中,与现场实际监测数据结果一致,验证了评价模型的准确性和有效性。 展开更多
关键词 垃圾填埋场 稳定性 评价指标体系 集对分析 敏感性分析 组合赋权 风险评价
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Cost Sensitive Multi-Granulation Preference Relation Rough Set for Ordinal Decision System 被引量:1
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作者 Wei Pan Kun She 《Journal of Electronic Science and Technology》 CAS CSCD 2017年第3期289-302,共14页
The preference analysis is a class of important issues in multi-criteria ordinal decision making.The rough set is an effective approach to handle preference analysis.In order to solve the multi-criteria preference ana... The preference analysis is a class of important issues in multi-criteria ordinal decision making.The rough set is an effective approach to handle preference analysis.In order to solve the multi-criteria preference analysis problems,this paper improves the preference relation rough set model and expands it to multi-granulation cases.Cost is also an important issue in the field of decision analysis.Taking the cost into consideration,we also expand the model to the cost sensitive multi-granulation preference relation rough set.Some theorems are represented,and the granule structure selection based on approximation quality is investigated.The experimental results show that the multi-granulation preference rough set approach with the consideration of cost has a better performance in granule structure selection than that without cost consideration. 展开更多
关键词 index Terms-Cost multi-granulation rough set preference relation rough set
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北京山区不同植被恢复类型土壤质量综合评价 被引量:3
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作者 李鹏 齐实 +8 位作者 张林 胡俊 唐颖 逯进生 王翔宇 赖金林 廖瑞恩 张岱 张岩 《水土保持学报》 CSCD 北大核心 2024年第1期337-346,356,共11页
[目的]综合评价北京山区不同植被恢复类型土壤质量,并进一步确定影响土壤质量的关键因素,为该地区植被恢复与重建提供数据支撑。[方法]以立地条件相近的侧柏纯林、油松纯林、侧柏油松混交林、侧柏针阔混交林、油松针阔混交林、落叶阔叶... [目的]综合评价北京山区不同植被恢复类型土壤质量,并进一步确定影响土壤质量的关键因素,为该地区植被恢复与重建提供数据支撑。[方法]以立地条件相近的侧柏纯林、油松纯林、侧柏油松混交林、侧柏针阔混交林、油松针阔混交林、落叶阔叶混交林和无林地(对照)为研究对象,测定14个土壤理化指标作为土壤质量评价的总数据集(TDS),采用主成分分析法(PCA)和Pearson相关性分析建立土壤质量最小数据集(MDS),利用线性(L)和非线性(NL)2种评分方法计算土壤质量指数(SQI)和一般线性模型(GLM)确定影响土壤质量的关键因素。[结果]植被恢复后相较于无林地,土壤容重、砂粒含量下降,而有机质、全氮、全钾、速效氮、速效钾等土壤养分含量增加。筛选出的研究区土壤质量评价MDS指标为全氮、砂粒、全钾、pH、有效含水量。4种方法(SQI-LT、SQI-NLT、SQI-LM、SQI-NLM)下,不同植被恢复类型的SQI值排序均为落叶阔叶混交林>侧柏针阔混交林>油松纯林>油松针阔混交林>侧柏油松混交林>侧柏纯林>无林地,植被恢复后土壤质量显著提升。SQI-NLM的土壤质量评价方法在北京山区具有更好的适用性。相较于无林地,其他植被恢复类型的SQI-NLM分别提高64%,48%,45%,36%,33%,27%。GLM模型解释了土壤质量指数总变异的85.24%,植被类型对土壤质量指数的解释比例最大(45.09%)。[结论]选择适宜的植被恢复类型是改善区域土壤质量的关键。未来实施植被恢复时,树种选择上优先考虑阔叶树种。造林配置方式的选择应取决于树种而定,如侧柏纯林中引入本土阔叶树种形成侧柏针阔混交林或选择油松纯林是最佳造林模式。 展开更多
关键词 植被恢复 土壤质量指数(SQI) 最小数据集(MDS) GLM 北京山区
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Core Competitiveness Evaluation of Financial Institution with Rough Sets and Gray Correlation Analysis
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作者 蔡红 翟育明 孙天慧 《Journal of Donghua University(English Edition)》 EI CAS 2016年第4期640-643,共4页
The comprehensive evaluation method of enterprise core competitiveness is proposed by combining rough sets and gray correlation theories. Firstly,the initial index is screened through rough set attribute reduction alg... The comprehensive evaluation method of enterprise core competitiveness is proposed by combining rough sets and gray correlation theories. Firstly,the initial index is screened through rough set attribute reduction algorithm,and the evaluation weight of each index is obtained through the rough set theory. Then,based on the gray correlation theory, an evaluation model is built for empirical analysis. The 30 financial institutions on the Yangtze River Delta are examined from the theoretical and empirical perspective.The result demonstrates not only the feasibility of rough set attribute reduction algorithm in the core competitiveness index system of the financial institution,but also the accuracy of the combination of these two methods in the comprehensive evaluation of corporate core competitiveness. 展开更多
关键词 Correlation attribute institutions empirical Institution partition Yangtze maintain performing steps
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基于Rough Set约简的供应商评价指标
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作者 罗如学 《西安邮电学院学报》 2010年第2期89-92,共4页
基于供应链环境下,采用Rough Set约简的方法,通过定量和定性相结合建立供应商评价选择指标体系,对供应商评价选择指标进行约简分析,并有效地避免了供应商评价指标的设计中出现的冗余或重复性。
关键词 供应商选择 指标体系 粗糙集
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Comprehensive Evaluation of School Sports Mordemization Based on Rough Set
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作者 Yu Feng Wu Yi Shao Xianming Guo Jianchun 《Journal of Zhouyi Research》 2014年第3期59-60,共2页
关键词 学校体育 粗糙集理论 综合评价 教育现代化 影响系统 中国现代化 资源体系 管理体系
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基于集对分析的用水定额评估方法及应用
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作者 张欣 张保祥 吴振 《水电能源科学》 北大核心 2024年第9期194-198,共5页
为深入贯彻落实“四水四定”原则,提升水资源节约集约安全利用水平,建立由覆盖性评估、规范性评估、合理性评估、先进性评估和实用性评估构成的用水定额评估指标体系及分级标准。基于集对分析理论构建用水定额评估模型,采用五元减法集... 为深入贯彻落实“四水四定”原则,提升水资源节约集约安全利用水平,建立由覆盖性评估、规范性评估、合理性评估、先进性评估和实用性评估构成的用水定额评估指标体系及分级标准。基于集对分析理论构建用水定额评估模型,采用五元减法集对势识别出较差的单指标。将该方法应用于我国华北缺水地区典型工业行业用水定额评估中,结果表明,山东省医药制造业重点工业产品用水定额总体评估结果为“宽松”,行业类别覆盖比例等7个指标的集对势处于反势或偏反势,可作为用水定额修订需要重点完善的内容。基于集对分析的用水定额评估方法系统实用,克服了评估指标覆盖不全面的缺陷,可以给出用水定额合理客观的评估结论,对于确保用水定额始终满足节水管理的需求具有重要意义。 展开更多
关键词 典型工业行业 用水定额评估 评估指标体系 集对分析 五元减法集对势
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An Approach to Spectral Discrimination of Rocks Using ASAI and Rough Sets
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作者 ZhangZhenfei HuGuangdao +5 位作者 YangMingguo LiuXing WangZhenlmi LiWenhui ZhangXiaobing HeLi 《Journal of China University of Geosciences》 SCIE CSCD 2003年第3期257-260,共4页
Field data of outcrop spectrums provide important basis for modeling of hyper-spectral remote sensing aiming at mineral prospecting. We make an approach to the application of rough set theory in spectral discriminatio... Field data of outcrop spectrums provide important basis for modeling of hyper-spectral remote sensing aiming at mineral prospecting. We make an approach to the application of rough set theory in spectral discrimination of rocks. We build a decision table with an adequate number of samples (outcrops) of known rock type (the universe), of which the conditional attributes are discretized 'area spectrum absorption indexes' (ASAI) corresponding to wavelength intervals, and the decision attribute is rock type. We search to obtain the exhaustive set of reducts of the table, each of which will serve as a variable number of deduction rules. Suppose we have n (usually a very big number) rules in total and there are m types of rocks in our universe, for any unknown sample, we judge its rock type by each of those rules. An unknown sample may be recognized as a different type by different rules because it is outside our universe, and we accept the most frequent judgment result and ignore the other m-1 types of results. Our ASAI is an improvement upon the traditional spectrum absorption index (SAI), better applicable to field spectrums: given a spectrum curve and a wavelength interval, we take the average reflectance within the interval as a base line and let ASAI=a below/(a above+a below), where a below and a above stand for total areas, bounded by the curve, the base line and the borders of the intervalbelow and above the base line respectively. With the equipments of FieldSpectr Fr (made by ASD Co., US), we collected data from Baiya gold deposit, Yunnan, and applied the above method to discriminate altered rocks as an experiment. The results show satisfactory performance of the method. 展开更多
关键词 rough set spectral discrimination area spectrum absorption index
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公里网格尺度的陕西冬小麦综合遥感指数保险产品设计
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作者 陈妍 薛子怡 +2 位作者 王彤 王东 姬便便 《中国农业气象》 CSCD 2024年第10期1204-1215,共12页
基于遥感时序数据MOD13A2和陕西省99个气象站点的逐日气象数据,使用EVI差值法提取陕西冬小麦种植区,筛选与冬小麦单产相关性最高的遥感指数,结合冬小麦生育期内倒春寒、干旱、连阴雨以及干热风4个农业气象灾害的气象指标,构建综合遥感... 基于遥感时序数据MOD13A2和陕西省99个气象站点的逐日气象数据,使用EVI差值法提取陕西冬小麦种植区,筛选与冬小麦单产相关性最高的遥感指数,结合冬小麦生育期内倒春寒、干旱、连阴雨以及干热风4个农业气象灾害的气象指标,构建综合遥感指数模型,以覆盖冬小麦全生育期的农业气象灾害风险。基于最优产量预测模型设计冬小麦综合遥感指数保险,采用分布拟合和蒙特卡洛模拟方法,计算10770个公里网格冬小麦综合遥感指数保险的理赔门槛值和精算纯费率,绘制理赔门槛地图和精算纯费率地图。结果表明:(1)采用EVI差值法提取冬小麦种植区,不同区域使用不同差值时段和门槛值,可获得较高提取精度,县域提取面积与2020年实际播种面积的相关系数达0.997,平均绝对误差524.9hm²;(2)2000-2020年第65、81天EVI及两者最大值与陕西冬小麦单产相关性较高,县域相关系数年平均值最高达0.692;(3)融合干旱、连阴雨和倒春寒3个农业气象灾害的气象指标,最优综合遥感指数模型模拟单产与实际单产的相关系数达0.837,最优综合遥感指数模型R²为0.602;(4)关中、陕南部分地区冬小麦种植风险较低,平均单产损失率低于2%,渭河与黄河交口处冬小麦种植风险较高,平均单产损失率高于4%,其余地区冬小麦种植风险介于两者之间。冬小麦单产和种植风险在县域以下区域存在较大空间差异,提高测算理赔门槛和精算纯费率的空间精度,能够使冬小麦高产地区和低产地区获得同样的赔付机会,避免赔付超过实际损失导致的道德风险,同时能够使费率与实际种植风险相匹配,增加费率公平性,提高低风险地区参保意愿,减少逆选择。 展开更多
关键词 遥感指数保险 冬小麦 费率厘定 EVI
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