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Binary Image Watermarking Algorithm Using Matrix of Complexity Index
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作者 张帆 张军亮 沈夏炯 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第6期651-654,共4页
A new watermarking algorithm of binary image is proposed.The complexity index of pixels is presented to reflect the change degree of pixels and to evaluate the modifiable degree of pixels.Firstly, in a small image blo... A new watermarking algorithm of binary image is proposed.The complexity index of pixels is presented to reflect the change degree of pixels and to evaluate the modifiable degree of pixels.Firstly, in a small image block, the complexity index of"jumping-change"is calculated in vertical and horizontal direction.Secondly, the matrix of the complexity index is calculated by integrating the complexity index of pixels in two directions.Finally, the matrix of the complexity index is used to embed the watermark in binary images.Experimental results show that the proposed algorithm has a good performance. 展开更多
关键词 binary image WATERMARK complexity index complexity index matrix
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Transmission Index Research of Parallel Manipulators Based on Matrix Orthogonal Degree 被引量:4
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作者 Zhu-Feng Shao Jiao Mo +1 位作者 Xiao-Qiang Tang Li-Ping Wang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第6期1396-1405,共10页
Performance index mance evaluation, and is the is the standard of perfor- foundation of both perfor- mance analysis and optimal design for the parallel manipulator. Seeking the suitable kinematic indices is always an ... Performance index mance evaluation, and is the is the standard of perfor- foundation of both perfor- mance analysis and optimal design for the parallel manipulator. Seeking the suitable kinematic indices is always an important and challenging issue for the parallel manipulator. So far, there are extensive studies in this field, but few existing indices can meet all the requirements, such as simple, intuitive, and universal. To solve this problem, the matrix orthogonal degree is adopted, and generalized transmission indices that can evaluate motion/force trans- missibility of fully parallel manipulators are proposed. Transmission performance analysis of typical branches, end effectors, and parallel manipulators is given to illus- trate proposed indices and analysis methodology. Simula- tion and analysis results reveal that proposed transmission indices possess significant advantages, such as normalized finite (ranging from 0 to l), dimensionally homogeneous, frame-free, intuitive and easy to calculate. Besides, pro- posed indices well indicate the good transmission region and relativity to the singularity with better resolution than the traditional local conditioning index, and provide a novel tool for kinematic analysis and optimal design of fully parallel manipulators. 展开更多
关键词 Transmission index Parallel mechanism Kinematic performance matrix orthogonal degree
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Novel Distance-Related Matrix Index and QSPR Research for Thermodynamics of Methyl Halides
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作者 杨海浪 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2004年第1期41-43,共3页
A novel topological index W F is defined by the matrices X,W and L as W F=XWL.The topological index WF based on the distance-related matrix of molecular graphs is used to code the structural environment of each atom... A novel topological index W F is defined by the matrices X,W and L as W F=XWL.The topological index WF based on the distance-related matrix of molecular graphs is used to code the structural environment of each atom-type in a molecular graph.Good QSPR models have been obtained for standard formation enthalpy of methyl halides.The result indicates that the idea of using multiple matrices to define the distance-related matrix topological index is valid. 展开更多
关键词 distance matrix topological index methyl halides
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Comparing of Aviation Network Structure of Mid-south,Northwest and Southwest of China Based on Hierarchical Index Model 被引量:1
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作者 Cheng Xiangjun Yang Fang Xie Li 《Journal of Traffic and Transportation Engineering》 2020年第1期14-19,共6页
In order to compare the aviation network of mid-south,northwest and southwest of China to reveal the structure similarity and difference for providing quantitative evidence to construct regional aviation network and i... In order to compare the aviation network of mid-south,northwest and southwest of China to reveal the structure similarity and difference for providing quantitative evidence to construct regional aviation network and improve its structure,hierarchical index model of regional aviation network was established through dividing the aviation network into layers to research its structure characters.Data matrixes were defined to record the basic state of regional aviation network.Index matrixes were constructed to describe the quantitative features of regional aviation network.On the basis of these indexes,several structure indexes of all layers of aviation network were calculated to show the structure features of aviation network,such as ratio of passenger volume within the region with across the region,share rate of passenger volume among layers,ratio of average number of airline for each airport,ratio of average passenger volume for each airline and ratio of airline rate.According to the statistical data,similar structure of share rate of passenger volume among layers and average passenger volume for each airline in their regional aviation network was found after calculating.But on the side of ratio of passenger volume within the region with across the region,ratio of average number of airlines for each airport and ratio of airline rate were different. 展开更多
关键词 Regional aviation network comparing of structure hierarchical index model index matrix structure index
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Discussions on the Relation between Rank and the Number of Non-zero Eigenvalue of Matrix
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作者 Xiquan WANG Guanghua WU 《International Journal of Technology Management》 2015年第5期85-86,共2页
This paper gives the rank of matrix and equalities and inequalities of the difference number of non-zero eigenvalue, and discuss the equivalent description of multi angle of equalities for upper and lower bounds of th... This paper gives the rank of matrix and equalities and inequalities of the difference number of non-zero eigenvalue, and discuss the equivalent description of multi angle of equalities for upper and lower bounds of the inequality. 展开更多
关键词 Rank of a matrix Non-zero eigenvalue matrix index
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Solution of Matrix Game with Triangular Intuitionistic Fuzzy Pay-Off Using Score Function 被引量:2
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作者 Sibasis Bandyopadhyay Prasun Kumar Nayak Madhumangal Pal 《Open Journal of Optimization》 2013年第1期9-15,共7页
Using score function in a matrix game is very rare. In the proposed paper we have considered a matrix game with pay-off as triangular intuitionistic fuzzy number and a new ranking order has been proposed using value j... Using score function in a matrix game is very rare. In the proposed paper we have considered a matrix game with pay-off as triangular intuitionistic fuzzy number and a new ranking order has been proposed using value judgement index, available definitions and operations. A new concept of score function has been developed to defuzzify the pay-off matrix and solution of the matrix game has been obtained. A numerical example has been given in support of the proposed method. 展开更多
关键词 TRIANGULAR Intuitionistic Fuzzy Number matrix GAME Value JUDGEMENT index SCORE Function
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Influential Observations in Stochastic Model of Divisia Index Numbers with AR(1) Errors
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作者 Syed Muhammed Aqil Burney Arfa Maqsood 《Applied Mathematics》 2014年第6期975-982,共8页
We use the general form of hat matrix and DFBETA measures to detect the influential observations in order to estimate the Divisia price index number when the error structure is first order serial correlation. An examp... We use the general form of hat matrix and DFBETA measures to detect the influential observations in order to estimate the Divisia price index number when the error structure is first order serial correlation. An example is presented with reference to price data of Pakistan. Hat values show the noteworthy findings that the corresponding weights of consumer items have large influence on the parameter estimates and are not affected by the parameter of autoregressive process AR(1). Whereas DFBETAs for Divisia index numbers depend on both the weights and autoregressive parameter. 展开更多
关键词 HAT matrix DFBETA Divisia index NUMBER Influential OBSERVATION AUTOREGRESSIVE Process
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Condensed Matrix Descriptor for Protein Sequence Comparison
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作者 Soumen Ghosh Jayanta Pal +1 位作者 Bansibadan Maji Dilip Kumar Bhattacharya 《International Journal of Analytical Mass Spectrometry and Chromatography》 2016年第1期1-13,共13页
The present paper develops a novel way of reducing a protein sequence of any length to a real symmetric condensed 20 × 20 matrix. This condensed matrix can be nicely applied as a protein sequence descriptor. In f... The present paper develops a novel way of reducing a protein sequence of any length to a real symmetric condensed 20 × 20 matrix. This condensed matrix can be nicely applied as a protein sequence descriptor. In fact, with such a condensed representation, comparison of two protein sequences is reduced to a comparison of two such 20 × 20 matrices. As each square matrix has a unique Alley Index/normalized Alley Index, such index is conveniently used in getting distance matrix to construct Phylogenetic trees of different protein sequences. Finally protein sequence comparison is made based on these Phylogenetic trees. In this paper three types viz., NADH dehydrogenase subunit 3 (ND3), subunit 4 (ND4) and subunit 5 (ND5) of protein sequences of nine species, Human, Gorilla, Common Chimpanzee, Pygmy Chimpanzee, Fin Whale, Blue Whale, Rat, Mouse and Opossum are used for comparison. 展开更多
关键词 Amino Acids Condensed matrix Eigen Values matrix Invariants ALE index
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Analysis of the nonlinear dynamic characteristics of two-phase flow based on an improved matrix pencil method
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作者 Hongwei Li Junpeng Liu +1 位作者 Yunlong Zhou Bin Sun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第6期737-748,共12页
Gas–liquid two-phase flow is complex and has uncertainty in phase interfaces, which make the two-phase flow look very complicated. Even though the flow behavior(e.g. coalescence, crushing and separation) of single bu... Gas–liquid two-phase flow is complex and has uncertainty in phase interfaces, which make the two-phase flow look very complicated. Even though the flow behavior(e.g. coalescence, crushing and separation) of single bubble or bubble groups in the liquid phase looks random, combining some established characteristics and methodologies can find regularities among the randomness. In order to excavate the nonlinear dynamic characteristics of gas–liquid two-phase flow, the authors developed an improved matrix pencil(IMP) method to analyze the pressure difference signals of the two-phase flow. This paper elucidates the influence of signal length on MP calculation results and the anti-noise-interference ability of the MP method. An IMP algorithm was applied to the fluctuation signals of gas–liquid two-phase flow to extract the mode frequency and damping ratio, which were combined with the component energy index(CEI) entropy to identify the different flow patterns. It is also found that frequency, damping ratio, CEI entropy and stability diagram together not only identify flow patterns, but also provide a new way to examine and understand the evolution mechanism of physical dynamics embedded in flow patterns. Combining these characteristics and methods, the evolution of the nonlinear dynamic physical behavior of gas bubbles is revealed. 展开更多
关键词 matrix pencil (MP) methodComponent energy index (CEI)Stability diagramFlow pattem identificationFlow dynamics
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Extracting the Influential Commodities in Stochastic Model of Simple Laspeyre Price Index Numbers with AR(2) Errors
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作者 Arfa Maqsood Syed Mohammad Aqil Burney 《Open Journal of Statistics》 2014年第3期220-229,共10页
This paper, on the first hand, deals with the problem of estimation of Laspeyre price index number when the errors are assumed to be generated from AR(2) process. The general expression of hat matrix and DFBETA measur... This paper, on the first hand, deals with the problem of estimation of Laspeyre price index number when the errors are assumed to be generated from AR(2) process. The general expression of hat matrix and DFBETA measure to find the influential consumer commodities in stochastic Laspeyre price model with AR(2) errors are developed on the other. The hat values show the noteworthy findings that the corresponding weights of consumer items have large influence on the parameter estimates for simple Laspeyre price index number and are not affected by the parameter of autoregressive process of order two. While, DFBETA measures are the functions of both weights and autocorrelation parameters. Lastly, an example is presented with reference to price data of Pakistan, and shows its practical importance in financial time series. 展开更多
关键词 HAT matrix DFBETA Laspeyre PRICE index Number Influential Observation AUTOREGRESSIVE Process
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Schedule Model for Project Portfolio Based on Design Structure Matrix
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作者 LI Sui-ke BAI Si-jun GUO Yu-tao 《International Journal of Plant Engineering and Management》 2013年第1期50-57,共8页
To improve the enterprise resource utilization and shorten the cycle of the whole project portfolio, a scheduling model based on Design Structure Matrix (DSM) is built. By setting the project activity weight index s... To improve the enterprise resource utilization and shorten the cycle of the whole project portfolio, a scheduling model based on Design Structure Matrix (DSM) is built. By setting the project activity weight index system and calculating the activity weight for the project portfolio, the constraint relationship between project portfolio information and resource utilization, as the two dimensions of the DSM, are fully reflected in the sched- ule model to determine the order of these activities of project portfolio. A project portfolio example is given to il- lustrate the applicability and effectiveness of the schedule model. 展开更多
关键词 project portfolio schedule model design structure matrix activity weight index system
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近20年来新疆入境旅游流质量研究
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作者 马燕 宋彩凤 《山西师范大学学报(自然科学版)》 2025年第3期92-97,共6页
运用旅游流流质指数、旅游接待指数-旅游流流质指数构建的二维矩阵,对近20年来新疆15个地州市入境旅游流质量进行了分析,结果表明:(1)从2000年到2009年,新疆入境旅游质量不高,2010年以后新疆入境旅游总体质量明显提升;(2)乌鲁木齐市属... 运用旅游流流质指数、旅游接待指数-旅游流流质指数构建的二维矩阵,对近20年来新疆15个地州市入境旅游流质量进行了分析,结果表明:(1)从2000年到2009年,新疆入境旅游质量不高,2010年以后新疆入境旅游总体质量明显提升;(2)乌鲁木齐市属于双高型,是新疆发展态势最好的;伊犁州直属县市和阿勒泰地区多属于外延增长型,高量低质;昌吉回族自治州、博尔塔拉蒙古自治州、塔城地区、克拉玛依市多属于双低型,发展态势不容乐观;石河子市在入境旅游者数量和收入上,都是极低的;喀什地区前期发展态势好,2008年后出现滑落;巴音郭楞蒙古自治州、阿克苏地区、克孜勒苏柯尔克孜自治州、和田地区多属于内生增长型,潜力大,但近年出现滑落;吐鲁番市前期发展态势好,2010年以后出现滑落;哈密市发展态势不好,但近期有所回升.并根据研究结果,提出了新疆地州市质量提升的对策建议. 展开更多
关键词 入境旅游 流质指数 二维矩阵 新疆
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基于模糊网络层次分析和群决策的测试性指标分配方法
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作者 张超 房颖涛 +2 位作者 董志杰 何世烈 周振威 《系统工程与电子技术》 北大核心 2025年第8期2570-2580,共11页
合理分配测试性指标是当前装备论证过程中的一项重要工作内容。针对按故障率分配等经典方法存在的计算方式单一等问题,提出一种基于模糊网络层次分析和群决策的测试性指标分配方法。首先,构建测试性指标影响因素权重评价体系,采用三角... 合理分配测试性指标是当前装备论证过程中的一项重要工作内容。针对按故障率分配等经典方法存在的计算方式单一等问题,提出一种基于模糊网络层次分析和群决策的测试性指标分配方法。首先,构建测试性指标影响因素权重评价体系,采用三角模糊数矩阵进行评分,运用网络层次分析法进行计算,利用群决策思想避免权重冲突。其次,引入S型函数,改进测试性指标分配函数,克服线性分配的局限性。最后,在机载系统上进行测试性指标分配应用验证。结果表明,该方法不仅有效结合客观计算与主观分析的优势,而且还综合考虑各项因素,是一种更为有效的测试性指标分配方法。 展开更多
关键词 测试性指标分配 三角模糊判断矩阵 网络层次分析法 群决策 S型函数优化
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秸秆基质块育秧对水稻幼苗生长生理及产量的影响 被引量:2
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作者 孙恩惠 张晶 +7 位作者 陈泽秋 雍宬 王秋君 周明 陈玲 曲萍 靳红梅 黄红英 《中国农业大学学报》 北大核心 2025年第5期42-52,共11页
为探究应用秸秆基质块(Straw matrix block,SMB)育秧对水稻幼苗生长及产量的影响,使用改性秸秆纤维为原料制备的SMB为育秧基质,以基质土为对照(CK),测定水稻幼苗壮秧指数、叶绿素含量、根系活力、根长、表面积、根体积、抗氧化酶活性及... 为探究应用秸秆基质块(Straw matrix block,SMB)育秧对水稻幼苗生长及产量的影响,使用改性秸秆纤维为原料制备的SMB为育秧基质,以基质土为对照(CK),测定水稻幼苗壮秧指数、叶绿素含量、根系活力、根长、表面积、根体积、抗氧化酶活性及产量构成等指标,并分析育秧过程中SMB释放的酚酸单体化合物的规律及对水稻秧苗生理指标的影响。结果表明:育秧周期(26 d)内,SMB的发芽指数(GI)可达72.39%,根系活力达244.52μg/(g·h),总根长较CK升高51.93%,根系发达。在第4天时,SMB幼苗根系中超氧化歧化酶(SOD)和谷氨酸合酶(GOGAT)活性、丙二醛(MDA)含量均出现最大值,分别达到1840.13 U/g、735.26 U/g和16.84 nmol/g,随后呈现逐渐下降趋势;而可溶性蛋白(SP)表现上升趋势,在第26天时达到16.11 mg/g。育秧过程中SMB释放的酚酸单体以对香豆酸(37.61~42.91μg/g)、反式阿魏酸(13.54~20.15μg/g)、香草醛(2.39~4.62μg/g)和4-羟基苯甲酸(1.17~1.78μg/g)为主;SMB秧龄14 d时的幼苗根中的SOD活性和MDA含量均显著低于CK;第4和14天的幼苗根系GOGAT活性比CK分别高29.70%和18.07%(P<0.05);第20―26天的秧苗根系可溶性蛋白含量升高31.73%(P<0.05);SMB释放的反式阿魏酸与水稻幼苗根系GOGAT活性呈显著负相关(P<0.05);使用SMB育秧能显著提高水稻有效穗、千粒重、理论和实际产量。综上,秸秆基质块(SMB)对水稻幼苗茎基宽、壮秧指数、可溶性蛋白、根系形态及产量等指标均具有显著的促进作用,适用于规模化水稻育苗生产。 展开更多
关键词 秸秆基质块 水稻秧苗 酚酸 根系形态 生理指标 抗氧化酶活性
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THE SPECTRAL PROPERTIES OF THE ITERATION MATRIX OF REGULAR SPLITTINGS FOR AN M-MATRIX
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作者 黎稳 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1995年第1期31-36,共6页
Let A=M-N be a regular splitting of an M-matrix. We study the spectral properties of the ineration matrix M-1N. Under a mild assumption on M-1 N. some necessary and sufficent conditions such that p(M-1N)=1 are obtaine... Let A=M-N be a regular splitting of an M-matrix. We study the spectral properties of the ineration matrix M-1N. Under a mild assumption on M-1 N. some necessary and sufficent conditions such that p(M-1N)=1 are obtained and the algebraic multiplicity and the index associated with eigenvalue 1 in M-1N are considered. 展开更多
关键词 M-matrix REGULAR splitting imalrix algebraic MULTIPLICITY of SPECTRAL redius index of SPECTRAL radius
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基于状态参数时序特征的核电厂重要设备通用健康状态评估方法
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作者 克立石 杜海虎 +2 位作者 杨小虎 张圣 黄立军 《核动力工程》 北大核心 2025年第3期229-235,共7页
针对核电设备现有健康状态评估方法存在准确性差、通用性低的问题,建立了一种基于状态参数时序特征的核电厂重要设备通用健康状态评估方法。该方法通过对状态参数进行时序特征分析,构建评估指标矩阵和评估模型,形成适用于核电厂多类设... 针对核电设备现有健康状态评估方法存在准确性差、通用性低的问题,建立了一种基于状态参数时序特征的核电厂重要设备通用健康状态评估方法。该方法通过对状态参数进行时序特征分析,构建评估指标矩阵和评估模型,形成适用于核电厂多类设备状态评估的通用方法。以不同厂家、不同型号的核电厂循环水泵为例,使用该方法进行健康状态评估,其准确率达93%以上,异常发现时间大幅提前,证明本研究建立的通用健康状态评估方法能够提高核电厂设备健康状态评估的准确性,适用于核电厂多种类型的设备。 展开更多
关键词 核电厂设备 状态参数时序特征 评估指标矩阵 通用健康评估
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基于灰度共生矩阵的水泥稳定碎石损伤表征指标
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作者 吕悦晶 李家琪 +3 位作者 魏彩霞 权磊 汤文 麻春杰 《江苏大学学报(自然科学版)》 北大核心 2025年第2期200-204,220,共6页
为了更好表征水泥稳定碎石损伤过程,基于灰度共生矩阵理论,提出了损伤表征指标——可移灰度级对(Psgl)和损伤度(D),分析了骨架空隙型和骨架密实型两种典型结构的水泥稳定碎石材料的损伤过程,计算水泥稳定碎石断面在不同损伤程度下的损... 为了更好表征水泥稳定碎石损伤过程,基于灰度共生矩阵理论,提出了损伤表征指标——可移灰度级对(Psgl)和损伤度(D),分析了骨架空隙型和骨架密实型两种典型结构的水泥稳定碎石材料的损伤过程,计算水泥稳定碎石断面在不同损伤程度下的损伤表征指标.结果表明:可移灰度级对可以表征水泥稳定碎石材料的损伤过程;随着荷载级位的增加,水泥稳定碎石的损伤度以二次抛物线的形式逐步增加,损伤的发展累积损伤度约占整个加载过程的80%;骨架空隙型结构试件的损伤发展速率在整体上要高于骨架密实型结构试件. 展开更多
关键词 水泥稳定碎石 裂纹 损伤表征指标 CT图像 灰度共生矩阵 可移灰度级对
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病例组合指数和权重在医院床位配置管理中的应用研究
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作者 黄利娟 朱振宇 刘伟 《中国卫生信息管理杂志》 2025年第3期471-477,共7页
目的通过病例组合指数(CMI)和权重指标对医院整体的床位配置及效能进行综合评价,为医院合理配置床位资源提供依据。方法以某三甲医院2022年12月至2023年11月各临床科室患者住院数据及医院医疗监测数据为基础,计算CMI调整前后床位数合理... 目的通过病例组合指数(CMI)和权重指标对医院整体的床位配置及效能进行综合评价,为医院合理配置床位资源提供依据。方法以某三甲医院2022年12月至2023年11月各临床科室患者住院数据及医院医疗监测数据为基础,计算CMI调整前后床位数合理区间并对现有床位数分季节进行判定,配对χ2检验用于比较调整前后结果的差异。使用波士顿矩阵判断床位利用类型,对床位数判定为合适或偏少的效率型科室通过CMI计算每床权重并排序。结果CMI调整后共有22个科室床位数判定为偏多,5个偏少,7个合适,CMI调整前后床位数判定结果差异无统计学意义。波士顿矩阵显示该院有18个效率型科室、14个周转型科室、2个闲置型科室,无压床型科室。CMI调整后床位数判定为合适或偏少的10个效率型科室中,CMI较高的科室对应的每床权重排名相较于床位利用指数排名有所上升。结论应用CMI及权重对床位利用及效能进行评价的方法,具有客观性和真实性,有利于优化医院床位资源配置,实现医院精细化管理。 展开更多
关键词 病例组合指数 床位配置 疾病诊断相关分组 波士顿矩阵 每床权重
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多策略改进SSA优化KELM的边坡稳定性预测模型 被引量:13
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作者 祁云 薛凯隆 +3 位作者 李绪萍 汪伟 白晨浩 吉准泽 《中国安全科学学报》 北大核心 2025年第3期92-98,共7页
为了能够更加精准地预测边坡稳定状态,从而有效预防边坡失稳事故,提出改进麻雀搜索算法(ISSA)与核极限学习机(KELM)相结合的ISSA-KELM边坡稳定性预测模型。首先,将边坡失稳特征中的容重、黏聚力等6个主要影响因素作为预测指标,建立边坡... 为了能够更加精准地预测边坡稳定状态,从而有效预防边坡失稳事故,提出改进麻雀搜索算法(ISSA)与核极限学习机(KELM)相结合的ISSA-KELM边坡稳定性预测模型。首先,将边坡失稳特征中的容重、黏聚力等6个主要影响因素作为预测指标,建立边坡稳定性评价数据集;其次,引入Sine混沌映射、Levy飞行策略、动态自适应权重以及融合最优爆炸策略和反向学习改进麻雀搜索算法(SSA),以提高其全局搜索能力和稳定性;而后利用ISSA优化KELM中的核参数ψ和正则化系数C,提升其预测精度,同时避免KELM出现过拟合现象;最后,对比分析ISSA-KELM模型与SSA-KELM、粒子群优化算法(PSO)-KELM以及PSO-支持向量机(SVM)模型的预测结果,并将ISSA-KELM模型应用于山西某露天煤矿。结果表明:ISSA-KELM模型的准确率、精确率、召回率和F 1分数分别达到了0.9459、1、0.8667和0.929,均优于SSA-KELM、PSO-KELM和PSO-SVM模型,模型的预测结果与实际值最为接近,表明所建ISSA-KELM模型具有较强的泛化能力。 展开更多
关键词 边坡稳定性 预测模型 改进麻雀搜索算法(ISSA) 核极限学习机(KELM) 预测指标 混淆矩阵
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基于融合特征矩阵和CNN模型的管道埋藏微裂纹超声导波定位
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作者 颜劲夫 艾星 +3 位作者 何其骏 李佳惠 胡碗铷 李义丰 《南京大学学报(自然科学版)》 北大核心 2025年第1期28-37,共10页
针对石化行业管道中埋藏微裂纹的检测和定位问题,提出了一种基于融合特征矩阵和卷积神经网络(Convolutional Neural Network,CNN)模型的新方法.首先,使用ABAQUS软件建立包含埋藏微裂纹的三维管道仿真模型,并部署传感器阵列采集超声导波... 针对石化行业管道中埋藏微裂纹的检测和定位问题,提出了一种基于融合特征矩阵和卷积神经网络(Convolutional Neural Network,CNN)模型的新方法.首先,使用ABAQUS软件建立包含埋藏微裂纹的三维管道仿真模型,并部署传感器阵列采集超声导波信号.然后,提取并融合两类特征因子来构建融合特征矩阵:反映微裂纹非线性特征的零频分量和表征微裂纹位置信息的损伤指数.最后,将该矩阵输入到构建的CNN模型中进行训练和测试,实现了对管道中埋藏微裂纹的精确定位.仿真分析结果表明,与传统的高次谐波分量相比,零频分量对微裂纹的非线性效应更敏感;损伤指数可以放大原始信号中包含的损伤信息,对埋藏微裂纹的定位具有重要价值;CNN模型可以有效地从融合特征矩阵中提取微裂纹的位置信息,确定其空间坐标,为无损检测领域管道微裂纹的定位提供了新的思路. 展开更多
关键词 零频分量 损伤指数 融合特征矩阵 CNN
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