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Linear Maps Preserving Idempotency of Products of Matrices on Upper Triangular Matrix Algebras
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作者 QI JING Ji GUO-XING 《Communications in Mathematical Research》 CSCD 2009年第3期253-264,共12页
Let Tn be the algebra of all n × n complex upper triangular matrices. We give the concrete forms of linear injective maps on Tn which preserve the nonzero idempotency of either products of two matrices or triple ... Let Tn be the algebra of all n × n complex upper triangular matrices. We give the concrete forms of linear injective maps on Tn which preserve the nonzero idempotency of either products of two matrices or triple Jordan products of two matrices. 展开更多
关键词 linear map matrix IDEMPOTENT product of two matrices triple Jordan product of two matrices
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Solving the generalized Sylvester matrix equation AV+BW=VF via Kronecker map
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作者 Aiguo WU Siming ZHAO Guangren DUAN 《控制理论与应用(英文版)》 EI 2008年第3期330-332,共3页
This note considers the solution to the generalized Sylvester matrix equation AV + BW = VF with F being an arbitrary matrix, where V and W are the matrices to be determined. With the help of the Kronecker map, an exp... This note considers the solution to the generalized Sylvester matrix equation AV + BW = VF with F being an arbitrary matrix, where V and W are the matrices to be determined. With the help of the Kronecker map, an explicit parametric solution to this matrix equation is established. The proposed solution possesses a very simple and neat form, and allows the matrix F to be undetermined. 展开更多
关键词 Kronecker map Sylvester matrix equation Parametric solution
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Co-commuting Mappings of Generalized Matrix Algebras
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作者 Liang Xin-feng Xiao Zhan-kui Du Xian-kun 《Communications in Mathematical Research》 CSCD 2015年第4期311-319,共9页
Let G be a generalized matrix algebra over a commutative ring R and Z(G) be the center of G. Suppose that F, T :G→G are two co-commuting R-linear mappings, i.e., F(x)x = xT(x) for all x ∈ G. In this note, we ... Let G be a generalized matrix algebra over a commutative ring R and Z(G) be the center of G. Suppose that F, T :G→G are two co-commuting R-linear mappings, i.e., F(x)x = xT(x) for all x ∈ G. In this note, we study the question of when co-commuting mappings on G are proper. 展开更多
关键词 co-commuting map generalized matrix algebra PROPER
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A novel interference suppression scheme applying complex weighted matrix interleaving mapping for UFMC systems
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作者 WANG Yunzhe MA Tianming +1 位作者 JIN Jie WU Zhong 《High Technology Letters》 EI CAS 2024年第4期380-388,共9页
In response to the problem of inter-carrier interference(ICI)and inter-subband interference(IBI)in the received signals of universal filtered multi-carrier(UFMC)systems,a novel interfer-ence suppression design scheme ... In response to the problem of inter-carrier interference(ICI)and inter-subband interference(IBI)in the received signals of universal filtered multi-carrier(UFMC)systems,a novel interfer-ence suppression design scheme applying the method of complex weighted matrix inter-leaving map-ping(CWMIM)is proposed on the basis of the existing suppression scheme of conjugate weighted butterfly interleaving mapping(CWBIM).The proposed scheme performs matrix interleaving map-ping on the transmitted signal,which not only improves the carrier interference ratio(CIR)of the received signal by combining the original IBI and ICI terms,but also further inhibits the probability of burst error in the received signal.Meanwhile,the scheme can further decrease the impact of phase rotation errors in the received signal by increasing the number of rotation factors.Theoretical analysis and simulation results demonstrate that compared with CWBIM-UFMC,the proposed CWMIM-UFMC can obtain more effective ICI and IBI suppression and better system bit error rate(BER)performance with only a little bit increase in computational complexity. 展开更多
关键词 universal filtered multi-carrier(UFMC) inter-carrier interference(ICI) inter-subband interference(IBI) complex weighted matrix interleaving mapping(CWMIM)
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Security Implementation in WSN with Symmetric and Matrix Mapping on Asymmetric ECC Cryptographic Techniques
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作者 S. Hemalatha V. Rajamani V. Parthasarathy 《Circuits and Systems》 2016年第10期3204-3211,共8页
As the wireless sensor networks are easily deployable, the volume of sensor applications has been increased widely in various fields of military and commercial areas. In order to attain security on the data exchanged ... As the wireless sensor networks are easily deployable, the volume of sensor applications has been increased widely in various fields of military and commercial areas. In order to attain security on the data exchanged over the network, a hybrid cryptographic mechanism which includes both symmetric and asymmetric cryptographic functions is used. The public key cryptographic ECC security implementation in this paper performs a matrix mapping of data’s at the points on the elliptical curve, which are further encoded using the private symmetric cipher cryptographic algorithm. This security enhancement with the hybrid mechanism of ECC and symmetric cipher cryptographic scheme achieves efficiency in energy conservation of about 7% and 4% compared to the asymmetric and symmetric cipher security implementations in WSN. 展开更多
关键词 WSN SECURITY Elliptic Curve Cryptography Symmetric Cipher Cryptography Hybrid Cryptosystem matrix mapping
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Hot deformation and processing maps of titanium matrix composite
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作者 王蕊宁 奚正平 +1 位作者 赵永庆 戚运莲 《中国有色金属学会会刊:英文版》 CSCD 2007年第A01期541-545,共5页
The hot deformation characteristics of TiC particles reinforced titanium matrix composite were studied in the temperature range from 900 ℃ to 1 150 ℃ and in the strain rate range of 10-3-10 s-1 by compression tests ... The hot deformation characteristics of TiC particles reinforced titanium matrix composite were studied in the temperature range from 900 ℃ to 1 150 ℃ and in the strain rate range of 10-3-10 s-1 by compression tests with Gleeble1500 simulator system. The flow behavior was described by the hyperbolic sine constitutive equation,and an average activation energy of 436.72 kJ/mol was calculated. The processing maps were calculated and analyzed according to the dynamic materials model. The maps show domains in some combinations of temperatures and strain rates and these domains are correlated with specific microstructural processes occurring during hot deformation by metallographic investigations and kinetic analysis. At the low strain rate domain occurs in the temperature range of 900-960 ℃ and strain rate range of 0.001-0.03 s-1 superplasticity and dynamic recrystallization were observed. At a high strain rate domain occurs in the temperature range of 980-1 120 ℃ and strain rate range of 0.1-10 s-1 the β phase undergoes dynamic recrystallization. Also,at a strain rate range of 0.1-10 s-1 and the temperature range of 900-930 ℃,the material exhibits flow localization. 展开更多
关键词 矩阵 化合物 热成型技术
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p38 MAPK及基质金属蛋白酶在心力衰竭病人心肌重构中的意义 被引量:7
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作者 杨永健 张鑫 杨大春 《中国病理生理杂志》 CAS CSCD 北大核心 2007年第8期1631-1632,1641,共3页
目的:探讨不同程度心力衰竭病人心肌组织丝裂素活化蛋白激酶(p38 MAPK)、基质金属蛋白酶家族(MMP-2、3、9)、细胞外基质(ECM)纤连蛋白(FN)表达与心肌重构的关系。方法:选择因二尖瓣关闭不全心脏病接受二尖瓣置换术的心力衰竭病人39例,... 目的:探讨不同程度心力衰竭病人心肌组织丝裂素活化蛋白激酶(p38 MAPK)、基质金属蛋白酶家族(MMP-2、3、9)、细胞外基质(ECM)纤连蛋白(FN)表达与心肌重构的关系。方法:选择因二尖瓣关闭不全心脏病接受二尖瓣置换术的心力衰竭病人39例,正常对照8例来自意外伤亡的器官捐献者。光镜检查心肌组织病理变化;免疫沉淀法检测心肌组织p38 MAPK磷酸化,及p38 MAPK、MMP-2、3、9蛋白表达;免疫荧光法检查心肌组织FN的分布。结果:瓣膜病所致心力衰竭病人心肌组织呈典型的心肌重构病理改变。心力衰竭组心肌p38 MAPK磷酸化明显强于对照组(P<0.05),随心功能恶化,其表达逐渐增加(P<0.05或P<0.01)。心力衰竭组心肌组织MMP-2、3、9蛋白表达明显强于正常对照组,各心力衰竭组与正常对照组相比差异显著(P<0.05或P<0.01);相反,心力衰竭组心肌组织FN蛋白表达明显弱于正常组,各心力衰竭组与正常对照组相比差异显著(P<0.05或P<0.01)。结论:心力衰竭病人通过激活p38 MAPK诱导心肌细胞肥大、坏死,通过MMP-2、3、9表达量的增高降解心肌细胞外基质FN,共同参与心肌重构的病理过程而恶化心功能。 展开更多
关键词 心肌重构 P38 map激酶 基质金属蛋白酶 细胞外基质
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基于MAP矩阵的绿色产品设计方法探索 被引量:4
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作者 周睿 陆瀚 姬彩霞 《生态经济》 CSSCI 北大核心 2014年第11期188-191,共4页
从绿色设计进行设计思考,以通过设计引导和促成民众的节能消费行为为核心目标,分析了绿色设计原则、设计视角与设计目标之间的整合关系,构建了针对绿色设计的MAP矩阵,并结合设计实践进行方法应用,从而探索通过MAP矩阵的绿色产品设计。
关键词 绿色设计 map矩阵 节能减排 消费行为 工业设计
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距骨骨软骨损伤MR T2-mapping与软骨基质金属蛋白酶-1表达的相关性研究 被引量:6
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作者 李伟 于泽晨 +4 位作者 贾岩波 于静红 海玲 乌日汗 白心雨 《磁共振成像》 CAS CSCD 北大核心 2021年第5期44-49,共6页
目的探讨距骨骨软骨损伤(osteochondral lesions of the talus,OLT)软骨基质金属蛋白酶-1(matrix metalloproteinase-1,MMP-1)的表达与磁共振T2值之间的关系及其在距骨骨软骨损伤的机制。材料与方法收集30例踝关节距骨骨软骨损伤行微创... 目的探讨距骨骨软骨损伤(osteochondral lesions of the talus,OLT)软骨基质金属蛋白酶-1(matrix metalloproteinase-1,MMP-1)的表达与磁共振T2值之间的关系及其在距骨骨软骨损伤的机制。材料与方法收集30例踝关节距骨骨软骨损伤行微创治疗术患者及30名健康志愿者,均行3.0 T常规踝关节磁共振成像(magnetic resonance imaging,MRI)及T2-mapping功能成像,测量距骨软骨T2值。术后离体距骨骨软骨行苏木精-伊红染色(hematoxylin-eosin staining,HE)和Western Blot法分析距骨骨软骨MMP-1的表达,统计学分析距骨骨软骨T2值与MMP-1蛋白表达的相关性。结果距骨骨软骨损伤以内中侧最为多见(磁共振6分区法),距骨骨软骨T2值随软骨损伤Mankin分级明显增大(P<0.05)。软骨MMP-1蛋白表达高级别与低级别差异明显(P<0.05)。软骨T2值与软骨MMP-1表达呈线性相关趋势,Pearson分析距骨骨软骨损伤T2值增加与MMP-1蛋白表达增加呈直线性正相关(r=0.821,P<0.0001)。结论距骨骨软骨损伤以内中侧最为多见,距骨骨软骨磁共振T2值随软骨损伤分级逐级递增;距骨骨软骨损伤磁共振T2值与MMP-1蛋白表达呈正相关,距骨骨软骨磁共振T2-mapping功能成像T2值定量分析可在体、无创性预测不同级别软骨损伤MMP-1蛋白的表达含量,为临床治疗OLT提供影像学定量依据。 展开更多
关键词 距骨骨软骨 T2-mapping 定量分析 基质金属蛋白酶-1 磁共振成像
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磁共振T_1ρ和T_2-mapping定量技术评估膝关节Ⅰ型胶原蛋白基质置入术后软骨修复 被引量:12
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作者 刘宇 黄勇 +2 位作者 郑穗生 陈其春 张佳 《临床放射学杂志》 CSCD 北大核心 2019年第3期512-516,共5页
目的探讨MRI T_1ρ和T_2-mapping成像技术定量评估膝关节Ⅰ型胶原蛋白基质置入术后软骨修复的应用价值。方法纳入20例膝关节Ⅰ型胶原蛋白置入术后患者(24处软骨损伤)作为试验组,并纳入20名健康志愿者作为对照组,试验组在术后3、6及12个... 目的探讨MRI T_1ρ和T_2-mapping成像技术定量评估膝关节Ⅰ型胶原蛋白基质置入术后软骨修复的应用价值。方法纳入20例膝关节Ⅰ型胶原蛋白置入术后患者(24处软骨损伤)作为试验组,并纳入20名健康志愿者作为对照组,试验组在术后3、6及12个月进行随访,所有患者均行MR检查,检查序列包括常规序列及T_1ρ、T_2-mapping序列。扫描结束后,通过工作站后处理,测量术区软骨的T_1ρ和T_2值。利用方差分析比较试验组各个时间段与对照组的T_1ρ和T_2值,用Pearson相关分析分析两者与术后修复时间的相关性。结果Ⅰ型胶原蛋白置入术后3个月,试验组软骨术区的T_1ρ和T_2值均显著高于正常对照组(P<0.05);术后6个月试验组术区T_1ρ和T_2值明显降低,但与正常对照组相比差异具有统计学意义(P<0.05);术后12个月术区T_1ρ和T_2值持续降低,与对照组相比,差异无统计学意义(P>0.05)。T_1ρ和T_2值与术后时间无明显相关性,术后3个月与6个月,以及术后6个月与12个月相比,P值分别为0.827、0.105、0.35、0.332。结论 MRI T_1ρ和T_2-mapping定量技术可通过反映术区软骨内生化成分的变化,动态追踪术后软骨的修复情况,T_1ρ和T_2-mapping均为临床提供有效的评估手段,具有较高的诊断价值。 展开更多
关键词 Ⅰ型胶原蛋白 软骨 T1ρ T2-mapping
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延龄草皂苷通过NF-κB/MAPK信号通路调控MMPs表达并抑制骨肉瘤Saos-2细胞的迁移和侵袭 被引量:13
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作者 李文军 康红兵 +3 位作者 杨立 聂跃华 艾小红 梅开 《肿瘤》 CAS CSCD 北大核心 2016年第9期968-976,共9页
目的:观察延龄草皂苷(diosgeninglucoside,Dgg)对人骨肉瘤Saos-2细胞增殖、凋亡、迁移和侵袭的影响,并探讨其可能的作用机制。方法:应用不同浓度(6.25~100gmol/L)的Dgg处理骨肉瘤Saos-2细胞96h后,采用CCK-8法检测细胞增殖... 目的:观察延龄草皂苷(diosgeninglucoside,Dgg)对人骨肉瘤Saos-2细胞增殖、凋亡、迁移和侵袭的影响,并探讨其可能的作用机制。方法:应用不同浓度(6.25~100gmol/L)的Dgg处理骨肉瘤Saos-2细胞96h后,采用CCK-8法检测细胞增殖情况。用不同浓度(12.5~50gmol/L)的Dgg作用骨肉瘤Saos-2细胞24h后,分别采用FCM和Transwell小室法检测细胞凋亡、迁移和侵袭能力的变化。最后,采用蛋白质印迹法检测Dgg(12.5和25μmol/L)作用后,Saos-2细胞中核因子κB(nuclear factor—κB,NF-κB)/丝裂原活化蛋白激酶(mitogen—activated protein kinase,MAPK)通路相关蛋白以及该通路下游效应分子基质金属蛋白酶(matrix metalloproteases,MMPs)的表达水平。结果:Dgg可明显抑制骨肉瘤Saos-2细胞的增殖,诱导细胞凋亡,抑制细胞迁移和侵袭(P值均〈0.05),并呈浓度和时间依赖性。Dgg下调NF—κB信号通路中p38的磷酸化(P〈0.05),但不影响细胞外信号调节激酶(extracellular signal—regulated kinase,ERK)和c-Jun氨基末端激酶(c-Jun N—terminal kinase,JNK)的磷酸化(P值均〉0.05)。Dgg抑制MAPK通路中磷酸化核因子κB激酶抑制蛋白(phospho—inhibitor of nuclear factor kappa—Bldnase,p-IKK)、磷酸化核因子κB抑制蛋白α(phospho—inhibitor of nuclear factor kappa—Bα,p-κBα)、IκBα和磷酸化p65(phospho—p65,p-p65)的表达(P值均〈0.05),并下调下游效应分子MMP-1、MMP-2和MMP-9的表达水平(p值均〈0.05)。结论:Dgg可抑制骨肉瘤细胞的增殖、迁移和侵袭,并促进细胞凋亡。这一作用可能与肿瘤细胞中NF—κB/MAPK信号通路被阻滞,以及MMPs表达被下调有关。 展开更多
关键词 骨肉瘤 抗肿瘤药(中药) map激酶信号系统 基质金属蛋白酶类 细胞迁移分析 肿瘤浸润 延龄草皂苷
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用Norm Matrix实现自组织映射网络的可视化 被引量:1
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作者 郭景峰 石丽红 《小型微型计算机系统》 CSCD 北大核心 2013年第11期2630-2634,共5页
自组织映射(SOM)算法已经被证实是一种非常有效的实现高维数据可视化的工具.但是SOM算法产生的结果——自组织映射网络必须借助于其他方法实现可视化,针对自组织映射网络的可视化方法 U-Matrix不能区分分离不明显的聚类的弊端,提出一种... 自组织映射(SOM)算法已经被证实是一种非常有效的实现高维数据可视化的工具.但是SOM算法产生的结果——自组织映射网络必须借助于其他方法实现可视化,针对自组织映射网络的可视化方法 U-Matrix不能区分分离不明显的聚类的弊端,提出一种新的可视化方法—Norm Matrix(N-Matrix),N-Matrix计算自组织映射网络的输出神经元权向量的范数,区别空间中不同神经元的绝对距离,并结合自组织映射网络特有的保持数据之间的拓扑邻域关系的性质,实现对自组织映射网络的可视化.实验结果证明,N-Matrix不仅可以实现分离明显聚类的可视化,还可以较好的实现分离不明显的聚类的可视化. 展开更多
关键词 自组织映射 N-矩阵 相对距离 绝对距离 不明显聚类 可视化
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一种基于MapReduce的知识聚类与统计机制 被引量:1
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作者 徐小龙 李永萍 《电子与信息学报》 EI CSCD 北大核心 2016年第1期202-208,共7页
网络文献知识库中的海量资源及其分类的粗粒度,导致学习者容易在文献检索和阅读过程出现认知迷航和知识过载问题。该文提出一种基于Map Reduce的知识聚类与统计机制:首先,提出基于Map Reduce的共现矩阵构建算法MR-Co Matrix;其次,将共... 网络文献知识库中的海量资源及其分类的粗粒度,导致学习者容易在文献检索和阅读过程出现认知迷航和知识过载问题。该文提出一种基于Map Reduce的知识聚类与统计机制:首先,提出基于Map Reduce的共现矩阵构建算法MR-Co Matrix;其次,将共现矩阵与相似度系数结合构建相似度矩阵;然后,通过Z Scores对相似度矩阵进行标准化;最后,使用离差平方和法(Ward,s method)对相似度矩阵进行聚类,生成树状的知识聚类谱系图;基于聚类结果,提出基于Map Reduce的知识文献统计算法MR-Statistics,对每个分类的知识属性进行统计。实验结果表明:将MR-Co Matrix和MR-Statistics方法应用于网络文献知识库进行知识聚类和统计,达到较理想的聚类精度和计算效率,实现了细粒度知识聚类和多维统计,同时减少了时间开销。 展开更多
关键词 数据挖掘 聚类 知识 共现矩阵 统计 map REDUCE
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DMS算法在Map/Reduce任务调度中的应用 被引量:2
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作者 裴树军 孔德凯 苗辉 《哈尔滨理工大学学报》 CAS 北大核心 2019年第1期71-77,共7页
云环境下传统的任务调度算法整体效率较低,为了提高任务调度的整体效率,在Map/Reduce基础上提出了一种基于处理时间的DMS任务调度算法。首先,对复杂任务进行预处理,将复杂任务转化为DAG图,依据任务依赖关系大小产生最佳拓扑排序,并依据... 云环境下传统的任务调度算法整体效率较低,为了提高任务调度的整体效率,在Map/Reduce基础上提出了一种基于处理时间的DMS任务调度算法。首先,对复杂任务进行预处理,将复杂任务转化为DAG图,依据任务依赖关系大小产生最佳拓扑排序,并依据排序结果将复杂任务交给work节点进行处理;其次,通过将节点处理任务的预测时间与节点处理能力的比值作为子任务在每个节点的处理"时间"进行量化建模,建立任务和处理时间的度量矩阵,依据DMS算法进行处理,从而获得任务分配最佳方案;最后,从任务调度效率与资源使用率的角度将DMS算法与公平调度算法、遗传算法行对比验证。实验结果表明,DMS算法能明显提高任务调度整体效率,充分利用各节点的计算能力提高了Map/Reduce的调度效率。 展开更多
关键词 云计算 map/REDUCE 任务调度 差值矩阵
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基质诱导的自体软骨移植术后3T磁共振T2mapping成像对移植软骨的分层定量评价 被引量:8
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作者 张君 徐贤 +4 位作者 李雪 陈敏 董天明 左盼利 安宁豫 《南方医科大学学报》 CAS CSCD 北大核心 2015年第1期141-145,共5页
目的评估磁共振T2mapping成像技术在基质诱导自体软骨移植(MACT)术后的定量分析价值。方法纳入6例膝关节MACT术后患者(9处软骨损伤),分别在术后3月、6月及12月进行磁共振动态随访检查,测量软骨修复区与正常对照区深浅两个区域及全层T2值... 目的评估磁共振T2mapping成像技术在基质诱导自体软骨移植(MACT)术后的定量分析价值。方法纳入6例膝关节MACT术后患者(9处软骨损伤),分别在术后3月、6月及12月进行磁共振动态随访检查,测量软骨修复区与正常对照区深浅两个区域及全层T2值,横向比较同一时间点修复区与正常区T2值差异,纵向评估术后3、6、12个月修复区T2值的变化。结果MACT术后3、6月移植区全层T2值显著高于邻近正常软骨(P均<0.05),术后12月修复区全层T2值变化较正常对照区无明显统计学差异(P=0.063)。术后6、12个月修复区浅层软骨T2值显著高于深层(P均<0.05)。术后3、6、12个月修复区深浅层T2值纵向变化均有统计学差异(P均<0.05)。结论 MACT术后磁共振T2mapping成像可作为评估关节软骨修复效果的重要依据。 展开更多
关键词 软骨修复 基质诱导的自体软骨细胞移植 磁共振成像 T2mapping
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基于DMC-PID串级算法的起步离合器MAP图控制 被引量:3
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作者 黄智明 张建武 +2 位作者 鲁统利 向玉德 刘金刚 《中国机械工程》 EI CAS CSCD 北大核心 2010年第9期1123-1128,共6页
分析了机械式自动变速器(AMT)车辆起步时离合器的接合过程。以降低起步冲击度和减小离合器滑摩功为目标,由油门开度、发动机转速、怠速目标转速以及一轴转速等参数提出了起步离合器MAP图控制策略。采用DMC-PID串级预测控制算法对离合器... 分析了机械式自动变速器(AMT)车辆起步时离合器的接合过程。以降低起步冲击度和减小离合器滑摩功为目标,由油门开度、发动机转速、怠速目标转速以及一轴转速等参数提出了起步离合器MAP图控制策略。采用DMC-PID串级预测控制算法对离合器位置进行了动态跟踪,充分发挥了DMC算法的超前预测性、强鲁棒性以及PID控制算法的抗干扰能力。在上海华普AMT样车上进行了起步离合器道路试验,所提出的起步离合器MAP图控制策略得到了成功应用。 展开更多
关键词 机械式自动变速器 起步离合器 map图控制 DMC-PID串级算法
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A self-adapting image encryption algorithm based on spatiotemporal chaos and ergodic matrix 被引量:3
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作者 罗玉玲 杜明辉 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第8期316-324,共9页
To ensure the security of a digital image, a new self-adapting encryption algorithm based on the spatiotemporal chaos and ergodic matrix is proposed in this paper. First, the plain-image is divided into different bloc... To ensure the security of a digital image, a new self-adapting encryption algorithm based on the spatiotemporal chaos and ergodic matrix is proposed in this paper. First, the plain-image is divided into different blocks of the same size, and each block is sorted in ascending order to obtain the corresponding standard ergodic matrix. Then each block is encrypted by the spatiotemporal chaotic system and shuffled according to the standard ergodic matrix. Finally, all modules are rearranged to acquire the final encrypted image. In particular, the plain-image information is used in the initial conditions of the spatiotemporal chaos and the ergodic matrices, so different plain-images will be encrypted to obtain different cipherimages. Theoretical analysis and simulation results indicate that the performance and security of the proposed encryption scheme can encrypt the image effectively and resist various typical attacks. 展开更多
关键词 spatiotemporal chaos ergodic matrix standard map image encryption
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ENUMERATIONS OF ONE-VERTEX MAPS WITH FACE PARTITION ON THE PLANE 被引量:3
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作者 吴发恩 刘彦佩 《Acta Mathematica Scientia》 SCIE CSCD 2000年第2期229-234,共6页
In addition to the known method given in [1], authors provide other three methods to the enumeration of one-vertex maps with face partition on the plane. Correspondingly, there are four functional equations in the enu... In addition to the known method given in [1], authors provide other three methods to the enumeration of one-vertex maps with face partition on the plane. Correspondingly, there are four functional equations in the enufuntion. It is shown that the four equations are equivalent. Moreover, an explicit expression of the solution is found by expanding the powers of the matrix of infinite order directly. This is a new complement of what appeared in [1]. 展开更多
关键词 map enufuntion functional equation infinite matrix
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Neural network-based matrix effect correction in EDXRF analysis 被引量:4
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作者 TUO Xianguo CHENG Bo MU Keliang LI Zhe 《Nuclear Science and Techniques》 SCIE CAS CSCD 2008年第5期278-281,共4页
In this paper we discuss neural network-based matrix effect correction in energy dispersive X-ray fluorescence (EDXRF) analysis,with detailed algorithm to classify the samples.The method can correct the matrix effect ... In this paper we discuss neural network-based matrix effect correction in energy dispersive X-ray fluorescence (EDXRF) analysis,with detailed algorithm to classify the samples.The method can correct the matrix effect effectively through classifying the samples automatically,and influence of X-ray absorption and enhancement by major elements of the samples is reduced.Experiments for the complex matrix effect correction in EDXRF analysis of samples in Pangang showed improved accuracy of the elemental analysis result. 展开更多
关键词 能量耗散X射线荧光分析 神经网络 聚类分析 基体效应 烧结矿物
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A Self-Adaptive Parallel Encryption Algorithm Based on Discrete 2D-Logistic Map 被引量:1
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作者 Jing Wang Guoping Jiang 《International Journal of Modern Nonlinear Theory and Application》 2013年第1期89-96,共8页
A self-adaptive parallel encryption algorithm based on discrete 2D-Logistic map is developed according to the position scrambling and diffusion of multi-direction in variable space of spatial chaos. The binary sequenc... A self-adaptive parallel encryption algorithm based on discrete 2D-Logistic map is developed according to the position scrambling and diffusion of multi-direction in variable space of spatial chaos. The binary sequences b1b2b3···bn are obtained according to the user key, in which the binary sequence 0 and 1 denote distribution mode of processors and the number of binary sequence n denotes cycle number. Then the pseudorandom 2D matrix is generated by 2D-Logistic map, and adaptive segmentation is applied in image matrix and pseudorandom matrix according to the value and the number of binary sequence. The parallel operation is used among blocks to improve efficiency and meet real-time demand in transmission processes. However, the pixel permutation is applied in partitioned matrix through ergodic matrix generated by pseudo-random matrix-block to decrease the correlation of adjacent pixels. Then the pixel substitution is used for fully diffusing through cipher block chaining mode until n cycles. The proposed algorithm can meet the three requirements of parallel operation in image encryption and the real-time requirement in transmission processes. The security is proved by theoretical analysis and simulation results. 展开更多
关键词 2D-Logistic map PSEUDO-RANDOM matrix THEORETICAL Analysis Simulation Results
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