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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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嫩江干流齐齐哈尔段可溶性有机物特征及溯源
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作者 朱立月 钱宁 +4 位作者 郭跃东 武双双 王楠 马洪艳 徐秋菊 《科学技术与工程》 北大核心 2026年第2期863-870,共8页
为了探究嫩江干流齐齐哈尔段水体可溶性有机物(DOM)的荧光光谱特征、来源及各来源贡献,通过三维荧光(3DEEM)-平行因子PARAFAC算法技术,定性分析了水体DOM的荧光组分特征,并结合荧光指数和主成分分析(principal component analysis,PCA)... 为了探究嫩江干流齐齐哈尔段水体可溶性有机物(DOM)的荧光光谱特征、来源及各来源贡献,通过三维荧光(3DEEM)-平行因子PARAFAC算法技术,定性分析了水体DOM的荧光组分特征,并结合荧光指数和主成分分析(principal component analysis,PCA)定量研究了水体DOM各荧光组分的化学性质、来源及贡献。结果表明,嫩江干流齐齐哈尔段水体DOM主要有机物组分有2种,分别是类富里酸组分C1和类色氨酸组分C2,其中C1荧光强度平均占比为82.0%。荧光指数结果表明,水体具有较强的腐殖化特征,腐殖化指数(HIX)平均值为0.82。主成分分析表明,水体DOM来源为内源和陆源混合型,PC1贡献率为48.1%,PC2贡献率为36.5%。可见,陆地上的土壤腐殖质、农业面源等陆源为嫩江干流齐齐哈尔段水体DOM的主要来源,水生生物及微生物代谢活动等内源为次要来源。 展开更多
关键词 三维荧光光谱 荧光指数 可溶性有机物 溯源分析
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安阳市土地利用景观格局时空演变特征及驱动因素分析
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作者 赵冬 郭兰博 +3 位作者 王业宁 陈心旸 王爱国 闫丽洁 《资源与产业》 2026年第1期118-128,共11页
城市化加速了土地利用景观格局的演变,而合理分析城市生态风险对保护城市生态环境和实现城市可持续发展具有重要意义。论文以河南省安阳市为研究区,采用土地利用转移矩阵、景观格局指数和热点分析等方法,并基于2000—2020年安阳市土地... 城市化加速了土地利用景观格局的演变,而合理分析城市生态风险对保护城市生态环境和实现城市可持续发展具有重要意义。论文以河南省安阳市为研究区,采用土地利用转移矩阵、景观格局指数和热点分析等方法,并基于2000—2020年安阳市土地利用数据,对安阳市土地利用景观格局演变特征进行分析,并利用主成分分析方法确定演化的主要驱动因素。研究结果表明:1)2000—2020年,安阳市土地利用演变格局呈现“三增两减”的趋势,即耕地、林地减少,草地、水域、建设用地增加,以耕地与建设用地之间的相互转化最为明显;2)2000—2020年,安阳市景观生态高风险区面积增加6 170.52 km^(2),景观生态风险等级逐渐升级,热点区域位于安阳市市区;3)2000—2010年,景观生态低风险区转向较高风险区,而2010—2020年景观生态较高风险区转向高风险区;4)景观格局演化是城市化水平指数、经济因子指数和人口密度共同作用的结果,产业结构因子对景观格局演化也有一定的影响。建议安阳市在城市化进程中,既要重视生态保护,又要因地制宜制定适宜区域土地利用良性发展的政策。 展开更多
关键词 转移矩阵 景观格局指数 热点分析 主成分分析 安阳市
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成都平原东缘土壤重(类)金属元素特征、来源解析与生态风险评估
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作者 李长顺 罗明 +3 位作者 刘兆鑫 范敏 张云辉 杨强 《甘肃科学学报》 2026年第1期129-139,共11页
土壤是生态环境的重要载体,而土壤中的重(类)金属元素对生态具有显著的潜在威胁。以四川省金堂县为研究区,采集表层土壤样品共291个,联合多种方法分析了该地区表层土壤中As、Cd、Cr、Hg、Pb、Cu、Ni和Zn共8种重(类)金属元素的污染特征... 土壤是生态环境的重要载体,而土壤中的重(类)金属元素对生态具有显著的潜在威胁。以四川省金堂县为研究区,采集表层土壤样品共291个,联合多种方法分析了该地区表层土壤中As、Cd、Cr、Hg、Pb、Cu、Ni和Zn共8种重(类)金属元素的污染特征和潜在来源。统计结果表明:以上8种重(类)金属元素的平均质量分数依次为8.01 mg/kg、0.19 mg/kg、66.10 mg/kg、0.06 mg/kg、19.95 mg/kg、21.22 mg/kg、30.47 mg/kg和66.53 mg/kg,除Cd和Hg外均未超过成都市表层土壤的背景值,其中Hg的变异程度最高。结合多元统计方法和正定矩阵因子分解模型解析得出研究区土壤重(类)金属元素的4个主要来源为:交通运输源、农业活动与成土母质混合源、燃煤排放源以及自然地质背景源。基于地累计指数和潜在生态风险指数评估了重(类)金属污染水平,结果显示研究区的土壤重(类)金属元素中除了Hg和Cd外,其余重(类)金属元素污染程度均较低,潜在生态风险最高的地区均位于城镇建设区域。研究结果进一步完善了研究区的土壤环境地球化学研究,可为国内外农业区土壤重(类)金属污染防治及区域可持续发展提供科学参考。 展开更多
关键词 重(类)金属元素 来源解析 正定矩阵因子分解模型 地累计指数 生态风险评估
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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 被引量:1
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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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考虑多因素的直流微网虚拟电容协同分配策略
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作者 孟建辉 周子欣 +1 位作者 王慧 顾立康 《电力工程技术》 北大核心 2025年第6期155-164,182,共11页
虚拟电容控制策略应用于直流微网各端口的变流器,使其模拟电容的充放电特性,是解决系统惯性问题、改善电压质量的有效方案。针对多储能单元并联运行时虚拟电容控制存在的协同分配问题,文中提出一种基于虚拟电容控制的多储能单元协同分... 虚拟电容控制策略应用于直流微网各端口的变流器,使其模拟电容的充放电特性,是解决系统惯性问题、改善电压质量的有效方案。针对多储能单元并联运行时虚拟电容控制存在的协同分配问题,文中提出一种基于虚拟电容控制的多储能单元协同分配策略,充分发挥各储能单元的惯性支撑能力。首先,根据直流电压变化率和荷电状态求取总可调虚拟电容值。其次,利用熵值法和评分矩阵对蓄电池的荷电状态、储能变流器的可调容量等指标综合评价,根据最终的评价得分求得分配系数,从而协同分配总虚拟电容。最后,搭建硬件在环仿真测试平台对所提策略进行验证,结果表明各储能单元能根据惯性能力合理分配虚拟电容,避免储能变流器因输出功率过大提前退出运行,进一步增强系统的惯性水平和安全稳定运行能力。 展开更多
关键词 直流微网 虚拟电容 协同控制 多指标综合评价 熵值法 评价矩阵
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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:5
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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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