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WIA-PA网络技术在井下人员定位系统中的应用 被引量:2
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作者 郭凯凯 李敬兆 李岩岩 《煤矿机械》 北大核心 2013年第1期254-256,共3页
从WIA-PA在通信中的优势出发,采用MSP430F1611和CC2520作为网络节点设计的核心器件,可以为井下人员定位系统提供较高质量的硬件功能;采用了天线放大器CC2591,可以将通信覆盖距离扩大到200 m,此系统解决了井下人员定位网络功能单一、组... 从WIA-PA在通信中的优势出发,采用MSP430F1611和CC2520作为网络节点设计的核心器件,可以为井下人员定位系统提供较高质量的硬件功能;采用了天线放大器CC2591,可以将通信覆盖距离扩大到200 m,此系统解决了井下人员定位网络功能单一、组网能力差和不能同时对多个移动目标实行定位的问题。为发生事故后进行有效救援提供了依据。肯定了WIA-PA值得研究的价值。 展开更多
关键词 WIA-pa MSP430F1611 CC2520 CC2591 井下人员定位系统
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NA、PA样本下密度核估计的相合性 被引量:12
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作者 文志诚 杨善朝 《数学研究》 CSCD 2002年第3期309-319,共11页
设 { Xn,n 1}为同分布的 NA或 PA随机变量序列 ,f (x)为 X1 概率密度函数 ,基于样本 X1 ,X2 ,… ,Xn,本文对密度函数 f (x)的核估计进行了讨论 ,在适当条件下证明了其强相合和 r阶矩相合 .
关键词 密度函数核估计 相合性 强相合 矩相合 NA样本 pa样本
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PA样本非参数回归权函数估计的强相合性 被引量:3
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作者 黎玉芳 杨善朝 《广西科学》 CAS 2003年第3期171-175,共5页
在 PA样本下 ,讨论非参数回归模型中权函数估计的强相合性及强一致相合性 .
关键词 pa样本 非参数回归 权函数估计 强相合性
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PA序列Chung型对数律的极限定理 被引量:2
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作者 傅可昂 《浙江大学学报(理学版)》 CAS CSCD 北大核心 2010年第6期625-628,共4页
设{Xn,n≥1}是一均值为零、方差有限的正相伴平稳序列.记Sn=sum Xk,Mn=maxx≤n|Sk|,n≥1 from k=1 to n,并假设0<σ2=EX12+2 sum E X1 Xk<∞ from k=2 to ∞.在E|X1|2+δ<∞,δ∈(0,1],以及对某个α>1,sum Cov(X1,Xj)=O(n-... 设{Xn,n≥1}是一均值为零、方差有限的正相伴平稳序列.记Sn=sum Xk,Mn=maxx≤n|Sk|,n≥1 from k=1 to n,并假设0<σ2=EX12+2 sum E X1 Xk<∞ from k=2 to ∞.在E|X1|2+δ<∞,δ∈(0,1],以及对某个α>1,sum Cov(X1,Xj)=O(n-α) from j=n+1 to ∞的条件下,建立了PA序列关于Chung型对数律的精确收敛速度. 展开更多
关键词 正相伴序列 对数律 收敛速度
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PA样本回归函数估计的强相合性 被引量:2
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作者 黎玉芳 《广西科学》 CAS 2011年第2期133-135,共3页
针对非参数回归模型Yi=g(xi)+εi,1≤i≤n,在{εi,1≤i≤n}为一致可积的平稳PA相依序列条件下,得到未知函数g(x)的权函数估计gn(x)=n∑i=1wn(x)Yi的强相合性.
关键词 权函数估计 强相合性 pa相依 一致可积
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肺炎患者血液PLT,PA/Fig和NGAL联合检测在不同类型病原菌感染鉴别及疗效评估中的价值 被引量:4
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作者 秦云 《现代检验医学杂志》 CAS 2021年第5期83-89,共7页
目的探讨肺炎患者血液血小板(PLT),前清蛋白纤维蛋白原比值(PA/Fig)和中性粒细胞明胶酶相关脂质运载蛋白(NGAL)联合检测在不同类型病原菌感染鉴别及疗效评估中的价值。方法选取2018年1月~2020年4月上海交通大学医学院附属新华医院崇明... 目的探讨肺炎患者血液血小板(PLT),前清蛋白纤维蛋白原比值(PA/Fig)和中性粒细胞明胶酶相关脂质运载蛋白(NGAL)联合检测在不同类型病原菌感染鉴别及疗效评估中的价值。方法选取2018年1月~2020年4月上海交通大学医学院附属新华医院崇明分院收治的52例革兰阴性菌感染肺炎患者(革兰阴性菌组)、52例革兰阳性菌感染肺炎患者(革兰阳性菌组)和52例真菌感染肺炎患者(真菌组),血培养或其生理无菌部位标本培养结果阳性,同期选取52例健康体检者(对照组),比较各组PLT,PA/Fig,NGAL和临床肺部感染(CPIS)评分,采用受试者工作特征曲线(ROC)及ROC下面积(AUC)分析PLT,PA/Fig,NGAL鉴别不同病原菌的效能,采用Pearson分析各组PLT,PA/Fig,NGAL与CPIS评分相关性,并比较不同疗效患者PLT,PA/Fig,NGAL,采用ROC与AUC分析PLT,PA/Fig和NGAL预测无效的效能。结果PLT:革兰阴性菌组[(116.59±24.61)×10^(9)/L]<革兰阳性菌组[(146.97±26.52)×10^(9)/L]<真菌组[(170.50±22.89)×10^(9)/L]<对照组[(220.18±25.39)×10^(9)/L]。PA/Fig:革兰阳性菌组(3.41±1.36)<革兰阴性菌组(5.68±1.20)<真菌组(7.97±1.21)<对照组(9.88±1.05)。NGAL:真菌组(129.87±48.25pg/ml)<对照组(162.01±21.39pg/ml)<革兰阴性菌组(302.49±50.88pg/ml)<革兰阳性菌组(368.44±54.67pg/ml),差异有统计学意义(F1=160.502,P1<0.001;F2=279.229,P2<0.001;F3=320.096,P3<0.001)。PLT,PA/Fig和NGAL鉴别革兰阳性菌、革兰阴性菌、真菌的AUC值均较高;革兰阳性菌、革兰阴性菌和真菌感染患者PLT,PA/Fig,NGAL均与CPIS评分相关;有效患者[PLT(153.97±20.47)×10^(9)/L,PA/Fig(6.18±1.06)]高于无效患者[(93.65±22.38)×10^(9)/L,3.00±0.97],差异有统计学意义(t=13.090,11.565,均P<0.05);PLT+PA/Fig预测无效的AUC为0.862,高于单一预测(0.808,0.778)。结论PLT,PA/Fig和NGAL可用于肺炎不同病原菌鉴别及病情评估,且PLT,PA/Fig和NGAL在预测疗效方面具有较高应用价值,可为临床诊治提供一定依据。 展开更多
关键词 肺炎 革兰阴性菌 革兰阳性菌 真菌 血小板 前清蛋白纤维蛋白原比值 中性粒细胞明胶酶相关脂质运载蛋白
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PA误差下回归函数小波估计的渐近性质(英文)
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作者 丁立旺 李永明 冯烽 《数学杂志》 CSCD 北大核心 2016年第3期533-542,共10页
本文研究了回归函数小波估计的渐进性质的问题.利用概率不等式方法,获得了函数g(·)的小波估计量的r-阶矩相合,依概率收敛和强收敛以及渐进正态性的结果,所获的结果推广了其他混合相依下的相应结果.
关键词 小波估计 正相协 相合性 渐近正态性
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一氧化氮合酶1、神经细胞PAS域蛋白4和外中心粒物质1基因型与偏执型精神分裂症表型的关联性
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作者 于洪岩 杨勇锋 +4 位作者 李文强 张红星 王秀娟 卢艳梨 吕路线 《新乡医学院学报》 CAS 2016年第11期954-958,共5页
目的探讨一氧化氮合酶1(NOS1)、神经细胞PAS域蛋白4(NPAS4)和外中心粒物质1(PCM1)基因单核甘酸多态性(SNP)与精神分裂症的关联性。方法选择来自豫北地区在河南省精神病医院住院的偏执型精神分裂症患者516例(病例组)和同地区健康正常人51... 目的探讨一氧化氮合酶1(NOS1)、神经细胞PAS域蛋白4(NPAS4)和外中心粒物质1(PCM1)基因单核甘酸多态性(SNP)与精神分裂症的关联性。方法选择来自豫北地区在河南省精神病医院住院的偏执型精神分裂症患者516例(病例组)和同地区健康正常人516例(对照组),采用荧光定量聚合酶链反应对NOS1、NPAS4和PCM1基因的5个功能SNP位点进行基因分型,分析SNP与疾病的关联性。进一步分析阳性和阴性症状量表(PANSS)因子分与NOS1、NPAS4和PCM1基因多态性的关联。结果 NOS1(rs3782219、rs3782221)、NPAS4(rs7947391)及PCM1(rs445422、rs370429)5个SNP位点基因型和等位基因频率在病例组和对照组中的分布差异均无统计学意义(P>0.05)。病例组与对照组NOS1基因的2个SNP位点(rs3782219、rs3782221)组成3种单体型(A-A、G-A、G-G)及PCM1基因2个SNP位点(rs445422、rs370429)组成3种单体型(A-A、G-A、G-G)频率的差异均无统计学意义(P>0.50)。NOS1基因的rs3782219基因型与兴奋/敌对因子,rs3782221基因型与抑郁/焦虑因子、兴奋/敌对因子的差异有统计学意义(P<0.05);NPAS4基因的rs7947391与阳性因子分的差异有统计学意义(P<0.05);PCM1基因的rs445422与PANSS总分、阴性因子分、认知因子分的差异有统计学意义(P<0.05),rs370429与PANSS总分、阴性因子、认知因子分的差异有统计学意义(P<0.05)。结论 NOS1基因的rs3782219和rs3782221位点、NPAS4基因的rs7947391位点以及PCM1基因的rs445422和rs370429位点可能不是精神分裂症的易感位点,但这些基因SNP位点基因型可能参与了精神分裂症表型特征。 展开更多
关键词 精神分裂症 一氧化氮合酶1 神经细胞paS域蛋白4 外中心粒物质1 单核苷酸多态性 阳性和阴性症状量表
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Linex损失下Pareto分布参数的EB估计:PA样本情形
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作者 何帮强 《安徽工程大学学报》 CAS 2011年第3期54-57,共4页
在Linex损失下,讨论了Pareto分布参数的经验Bayes(EB)估计.利用同分布PA样本下概率密度函数的核估计构造了参数的经验Bayes估计,建立了所提出经验Bayes估计的收敛速度.在一定的条件下该收敛速度可以任意接近于1.
关键词 LINEX损失 收敛速度 pa样本 paRETO分布
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PA序列生成的线性过程误差权函数估计的Berry-Esseen界
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作者 丁立旺 冯烽 《西南师范大学学报(自然科学版)》 CAS 北大核心 2016年第3期7-12,共6页
在由PA序列生成的线性过程误差下,讨论了非参数回归函数加权估计的Berry-Esseen界,其Berry-Esseen界可达O(n^(-1/6)).
关键词 pa序列 线性过程 权函数估计 BERRY-ESSEEN界
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PA样本下单边截断型分布族位置参数函数的经验Bayes估计 被引量:2
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作者 范国良 袁玲 凌能祥 《合肥工业大学学报(自然科学版)》 CAS CSCD 北大核心 2006年第9期1173-1176,共4页
对单边截断型分布族在同分布正相协(PA)样本下,构造了位置参数函数的经验Bayes(E.B)估计,由分析可知,在适当的条件下,证明了位置参数θ的函数的经验Bayes(E.B)估计的收敛速度为O(n-q),其中,q=λα(δ-2)/(2α+4)δ;α>0;0<λ<... 对单边截断型分布族在同分布正相协(PA)样本下,构造了位置参数函数的经验Bayes(E.B)估计,由分析可知,在适当的条件下,证明了位置参数θ的函数的经验Bayes(E.B)估计的收敛速度为O(n-q),其中,q=λα(δ-2)/(2α+4)δ;α>0;0<λ<δ/(1+δ);δ>2。 展开更多
关键词 pa样本 E·B估计 收敛速度
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PA相依样本的部分线性EV模型的估计理论
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作者 李晶晶 《宁波大学学报(理工版)》 CAS 2006年第4期493-497,共5页
考虑部分线性EV模型Y=xβ+g(t)+e,e是PA相依,其中x的观测值有误差时β和g(t)的估计情况.用x的有效数据和原始数据构造β和g(t)的非参数核估计,并且讨论了在某些条件下这些估计的强相合性。
关键词 pa相依 部分线生EV模型 强相合估计 有效数据
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PAS家族转录因子及其下游基因在大鼠肝再生中的作用
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作者 董华明 李静 徐存拴 《河南科技学院学报》 2009年第2期27-29,38,共4页
为在基因转录水平了解PAS结构域转录因子家族基因及它们的下游基因在肝再生(liver regeneration,LR)中作用,本文用Rat Genome 230 2.0芯片检测上述基因在大鼠再生肝中表达情况,用真、假手术比较方法确定肝再生相关基因。初步证实25个基... 为在基因转录水平了解PAS结构域转录因子家族基因及它们的下游基因在肝再生(liver regeneration,LR)中作用,本文用Rat Genome 230 2.0芯片检测上述基因在大鼠再生肝中表达情况,用真、假手术比较方法确定肝再生相关基因。初步证实25个基因与肝再生相关,它们在促进再生肝细胞分化及异源物、糖、脂代谢,促进肝再生早期的免疫反应和后期的血管发生中发挥作用。 展开更多
关键词 部分肝切除 Rat GENOME 230 2.0芯片 paS结构域家族转录因子 肝再生相关基因
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基于PROFIBUS-PA总线的锅炉液位控制系统
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作者 吕增芳 《中国西部科技》 2008年第36期29-30,21,共3页
阐述了PROFIBUS-PA现场总线的有关概念,指出了锅炉液位现场总线控制系统组成及其设计思想,同时给出了控制系统主要模块的组态方法以及上位机监控系统组态框架。该系统实际运行稳定、正常。
关键词 PROFIBUS-pa现场总线 智能仪表 锅炉液位控制系统 模块 组态
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Empirical Euclidean likelihood for general estimating equations under association dependence 被引量:1
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作者 CHEN You-you ZHANG Li-xin Department of Mathematics, Zhejiang University, Hangzhou 310027, China 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2010年第4期437-446,共10页
Empirical Euclidean likelihood for general estimating equations for association dependent processes is investigated. The strong consistency and asymptotic normality of the blockwise maximum empirical Euclidean likelih... Empirical Euclidean likelihood for general estimating equations for association dependent processes is investigated. The strong consistency and asymptotic normality of the blockwise maximum empirical Euclidean likelihood estimator are presented. We show that it is more efficient than estimator without blocking. The blockwise empirical Euclidean log-likelihood ratio asymptotically follows a chi-square distribution. 展开更多
关键词 Empirical Euclidean likelihood blockwise positive association negative association.
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Effects of microtopography on spatial point pattern of forest stands on the semi-arid Loess Plateau,China 被引量:4
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作者 WeiJun ZHAO Yan ZHANG +6 位作者 QingKe ZHU Wei QIN ShuZhen PENG Ping LI YanMin ZHAO Huan MA Yu WANG 《Journal of Arid Land》 SCIE CSCD 2015年第3期370-380,共11页
Microtopography may affect the distribution of forests through its effect on rain redistribution and soil water distribution on the semi-arid Loess Plateau,China.In this study,we investigated the characteristics of mi... Microtopography may affect the distribution of forests through its effect on rain redistribution and soil water distribution on the semi-arid Loess Plateau,China.In this study,we investigated the characteristics of microtopography on two shady slopes(slope A,5 hm2,uniform slope;slope B,5 hm2,microtopography slope) and surveyed the height,the diameter at breast height and the location(x,y coordinates) of all selected individual trees(Robinia pseudoacacia Linn.,Pyrus betulifolia Bunge,Populus hopeiensis Hu & Chow,Armeniaca sibirica Lam.,Populus simonii Carr.and Ulmus pumila Linn.) on slope A and slope B in the watersheds of Wuqi county,Shaanxi province.Subsequently,the effects of microtopography on the spatial pattern of forest stands were analyzed using Ripley's K(r) function.The results showed that:(1) The maximal aggregation radiuses of the tree species on the uniform slope(slope A) were larger than 40 m,whereas those of the tree species on the microtopography slope(slope B) were smaller than 30 m.(2) On slope B,the spatial association of R.pseudoacacia with P.betulifolia,A.sibirica,P.simonii and U.pumila varied from being strongly negative to positive at microtopography scales.The spatial association of Populus hopeiensis Hu & Chow with U.pumila also varied from being strongly negative to positive at microtopography scales.However,there was no spatial association between P.betulifolia and P.hopeiensis,P.betulifolia and A.sibirica,P.betulifolia and P.simonii,P.betulifolia and U.pumila,P.hopeiensis and A.sibirica,P.hopeiensis and P.simonii,A.sibirica and P.simonii,A.sibirica and U.pumila,and P.simonii and U.pumila.On slope A,the spatial association between tree species were strongly negative.The results suggest that microtopography may shape tree distribution patterns on the semi-arid Loess Plateau. 展开更多
关键词 microtopography univariate spatial patterns aggregation negative association positive association
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QUANTILE ESTIMATION WITH AUXILIARY INFORMATION UNDER POSITIVELY ASSOCIATED SAMPLES 被引量:1
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作者 李英华 秦永松 +1 位作者 雷庆祝 李丽凤 《Acta Mathematica Scientia》 SCIE CSCD 2016年第2期453-468,共16页
The empirical likelihood is used to propose a new class of quantile estimators in the presence of some auxiliary information under positively associated samples. It is shown that the proposed quantile estimators are a... The empirical likelihood is used to propose a new class of quantile estimators in the presence of some auxiliary information under positively associated samples. It is shown that the proposed quantile estimators are asymptotically normally distributed with smaller asymptotic variances than those of the usual quantile estimators. 展开更多
关键词 QUANTILE positively associated sample empirical likelihood
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An Improved Algorithm for Mining Correlation Item Pairs
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作者 Tao Li Yongzhen Ren +1 位作者 Yongjun Ren Jinyue Xia 《Computers, Materials & Continua》 SCIE EI 2020年第10期337-354,共18页
Apriori algorithm is often used in traditional association rules mining,searching for the mode of higher frequency.Then the correlation rules are obtained by detected the correlation of the item sets,but this tends to... Apriori algorithm is often used in traditional association rules mining,searching for the mode of higher frequency.Then the correlation rules are obtained by detected the correlation of the item sets,but this tends to ignore low-support high-correlation of association rules.In view of the above problems,some scholars put forward the positive correlation coefficient based on Phi correlation to avoid the embarrassment caused by Apriori algorithm.It can dig item sets with low-support but high-correlation.Although the algorithm has pruned the search space,it is not obvious that the performance of the running time based on the big data set is reduced,and the correlation pairs can be meaningless.This paper presents an improved mining algorithm with new association rules based on interestingness for correlation pairs,using an upper bound on interestingness of the supersets to prune the search space.It greatly reduces the running time,and filters the meaningless correlation pairs according to the constraints of the redundancy.Compared with the algorithm based on the Phi correlation coefficient,the new algorithm has been significantly improved in reducing the running time,the result has pruned the redundant correlation pairs.So it improves the mining efficiency and accuracy. 展开更多
关键词 INTERESTINGNESS item pairs positive correlation association rules REDUNDANCY
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Nutech functional score: A novel scoring system to assess spinal cord injury patients
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作者 Geeta Shroff Jitendra Kumar Barthakur 《World Journal of Methodology》 2017年第2期68-72,共5页
AIM To develop a new scoring system, nutech functional scores(NFS) for assessing the patients with spinal cord injury(SCI).METHODS The conventional scale, American Spinal Injury Association's(ASIA) impairment scal... AIM To develop a new scoring system, nutech functional scores(NFS) for assessing the patients with spinal cord injury(SCI).METHODS The conventional scale, American Spinal Injury Association's(ASIA) impairment scale is a measure which precisely describes the severity of the SCI.However, it has various limitations which lead to incomplete assessment of SCI patients.We have developed a 63 point scoring system, i.e., NFS for patients suffering with SCI.A list of symptoms either common or rare that were found to be associated with SCI was recorded for each patient.On the basis of these lists, we have developed NFS.RESULTS These lists served as a base to prepare NFS, a 63 point positional(each symptom is sub-graded and get points based on position) and directional(moves in direction BAD → GOOD) scoring system.For non-progressive diseases, 1, 2, 3, 4, 5 denote worst, bad, moderate, good and best(normal), respectively.NFS for SCI has been divided into different groups based on the affected part of the body being assessed, i.e., motor assessment(shoulders, elbow, wrist, fingers-grasp, fingers-release, hip, knee, ankle and toe), sensory assessment, autonomic assessment, bed sore assessment and general assessment.As probability based studies required a range of(-1, 1) or at least the range of(0, 1) to be useful for real world analysis, the grades were converted to respective numeric values.CONCLUSION NFS can be considered as a unique tool to assess the improvement in patients with SCI as it overcomes the limitations of ASIA impairment scale. 展开更多
关键词 Spinal cord injury American Spinal Injury association’s Impairment Scale Nutech functional score Comparison of assessment Positional scoring system
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Backward Support Computation Method for Positive and Negative Frequent Itemset Mining
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作者 Mrinmoy Biswas Akash Indrani Mandal Md. Selim Al Mamun 《Journal of Data Analysis and Information Processing》 2023年第1期37-48,共12页
Association rules mining is a major data mining field that leads to discovery of associations and correlations among items in today’s big data environment. The conventional association rule mining focuses mainly on p... Association rules mining is a major data mining field that leads to discovery of associations and correlations among items in today’s big data environment. The conventional association rule mining focuses mainly on positive itemsets generated from frequently occurring itemsets (PFIS). However, there has been a significant study focused on infrequent itemsets with utilization of negative association rules to mine interesting frequent itemsets (NFIS) from transactions. In this work, we propose an efficient backward calculating negative frequent itemset algorithm namely EBC-NFIS for computing backward supports that can extract both positive and negative frequent itemsets synchronously from dataset. EBC-NFIS algorithm is based on popular e-NFIS algorithm that computes supports of negative itemsets from the supports of positive itemsets. The proposed algorithm makes use of previously computed supports from memory to minimize the computation time. In addition, association rules, i.e. positive and negative association rules (PNARs) are generated from discovered frequent itemsets using EBC-NFIS algorithm. The efficiency of the proposed algorithm is verified by several experiments and comparing results with e-NFIS algorithm. The experimental results confirm that the proposed algorithm successfully discovers NFIS and PNARs and runs significantly faster than conventional e-NFIS algorithm. 展开更多
关键词 Data Mining positive Frequent Itemset Negative Frequent Itemset association Rule Backward Support
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