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改进的Pattern Matrix算法在图书管理中的应用
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作者 虞智辉 《电脑知识与技术》 2013年第11X期7577-7580,共4页
根据用户的信息和图书借阅所产生的数据,分析用户的需求,利用改进的Pattern Matrix算法,从中挖掘出用户数据间的关联性,自动判断用户可能的借阅需求,从而将相关的图书信息推送给用户,增强图书管理的主动服务功能。
关键词 数据分析 数据挖掘 pattern matrix算法 改进
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Pattern Matrix Design of PDMA for 5G UL Applications 被引量:4
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作者 Bin Ren Yingmin Wang +2 位作者 Xiaoming Dai Kai Niu Wanwei Tang 《China Communications》 SCIE CSCD 2016年第S2期159-173,共15页
Pattern division multiple access(PDMA),which is a novel non-orthogonal multiple access(NOMA),has been proposed to address the challenges of massive connectivity and higher spectral efficiency for fifth generation(5G) ... Pattern division multiple access(PDMA),which is a novel non-orthogonal multiple access(NOMA),has been proposed to address the challenges of massive connectivity and higher spectral efficiency for fifth generation(5G) mobile network.The performance of PDMA mainly depends on the design of PDMA pattern matrix.In this paper,pattern matrix design of PDMA for 5G uplink(UL) applications in massive machine type communication(mMTC) and enhanced mobile broadband(eMBB) deployment scenarios are studied.The design criteria and examples for application in UL mMTC and UL eMBB are investigated.The performance of the PDMA pattern matrix is analyzed with the discrete constellation constrained capacity(CC-Capacity),and verified by Monte Carlo simulation.The simulation results show that the preferred PDMA pattern matrix can achieve good performance with different overloading factors(OF). 展开更多
关键词 5G non-orthogonal multiple access PDMA pattern matrix CC-Capacity SIC
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Sign Patterns That Allow the Given Matrix
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作者 邵燕灵 孙良 《Journal of Beijing Institute of Technology》 EI CAS 2003年第3期316-318,共3页
Let P be a property referring to a real matrix. For a sign pattern A, if there exists a real matrix B in the qualitative class of A such that B has property P, then we say A allows P. Three cases that A allows an M m... Let P be a property referring to a real matrix. For a sign pattern A, if there exists a real matrix B in the qualitative class of A such that B has property P, then we say A allows P. Three cases that A allows an M matrix, an inverse M matrix and a P 0 matrix are considered. The complete characterizations are obtained. 展开更多
关键词 sign pattern M matrix inverse M matrix P 0 matrix
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FUZZY WITHIN-CLASS MATRIX PRINCIPAL COMPONENT ANALYSIS AND ITS APPLICATION TO FACE RECOGNITION 被引量:3
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作者 朱玉莲 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第2期141-147,共7页
Matrix principal component analysis (MatPCA), as an effective feature extraction method, can deal with the matrix pattern and the vector pattern. However, like PCA, MatPCA does not use the class information of sampl... Matrix principal component analysis (MatPCA), as an effective feature extraction method, can deal with the matrix pattern and the vector pattern. However, like PCA, MatPCA does not use the class information of samples. As a result, the extracted features cannot provide enough useful information for distinguishing pat- tern from one another, and further resulting in degradation of classification performance. To fullly use class in- formation of samples, a novel method, called the fuzzy within-class MatPCA (F-WMatPCA)is proposed. F-WMatPCA utilizes the fuzzy K-nearest neighbor method(FKNN) to fuzzify the class membership degrees of a training sample and then performs fuzzy MatPCA within these patterns having the same class label. Due to more class information is used in feature extraction, F-WMatPCA can intuitively improve the classification perfor- mance. Experimental results in face databases and some benchmark datasets show that F-WMatPCA is effective and competitive than MatPCA. The experimental analysis on face image databases indicates that F-WMatPCA im- proves the recognition accuracy and is more stable and robust in performing classification than the existing method of fuzzy-based F-Fisherfaces. 展开更多
关键词 face recognition principal component analysis (PCA) matrix pattern PCA(MatPCA) fuzzy K-nearest neighbor(FKNN) fuzzy within-class MatPCA(F-WMatPCA)
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激光微孔化脱细胞支架在组织再生中的应用
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作者 顾健美 袁坤山 +1 位作者 周强 张海军 《中国组织工程研究》 北大核心 2026年第2期499-506,共8页
背景:在组织工程领域,脱细胞支架因生物相容性良好而被广泛应用;然而,由于其结构致密,它们常常面临细胞浸润不足的挑战。采用激光微孔加工技术对脱细胞支架进行结构改性,能够改善细胞的黏附与增殖。目的:总结激光微孔化脱细胞支架在组... 背景:在组织工程领域,脱细胞支架因生物相容性良好而被广泛应用;然而,由于其结构致密,它们常常面临细胞浸润不足的挑战。采用激光微孔加工技术对脱细胞支架进行结构改性,能够改善细胞的黏附与增殖。目的:总结激光微孔化脱细胞支架在组织再生中的研究进展。方法:在中国知网和PubMed数据库中检索相关文献,中文检索词为“脱细胞支架、激光微图技术、激光微孔化脱细胞支架、细胞外基质、激光打孔、组织再生”,英文检索词为“decellularized scaffold、laser micro-patterning technology、laser microporous decellularized scaffold、extracellular matrix、laser drilling、tissue regeneration”。根据纳入与排除标准筛选文献,最终纳入65篇文献进行分析与讨论。结果与结论:①激光微图技术可以选择性去除组织实现支架改性,激光处理对支架的孔隙结构、机械性能、细胞渗透性均会产生影响且影响可控。②为了获得最优的细胞整合与重塑效果,应考虑支架预处理、激光与脱细胞技术工艺顺序、激光参数设定、脱细胞工艺和孔隙结构因素。③目前,激光微孔化脱细胞支架的应用显示其可以促进组织修复,但需要解决组织热损伤的问题,根据组织对不同波长激光的吸收,合理选择激光类型是一种可行的解决方案。④激光微孔化脱细胞支架进行组织损伤修复有望实现临床转化,优化激光工艺、开展更大规模的生物安全性测试是未来的研究方向。 展开更多
关键词 脱细胞支架 激光微图技术 细胞外基质 激光打孔 组织损伤 再细胞化 组织再生 工程化生物材料 组织工程
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THE STRUCTURE OF TRIPOTENT SIGN PATTERN MATRICES 被引量:2
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作者 Li Jiongsheng Gao Yubin Project supported by the National Natural Science Foundation of China (19971086).Dept. of Math., Univ. of Science and Technology of China, Hefei 230026 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第1期1-7,共7页
A matrix whose entries are +,-, and 0 is called a sign pattern matrix. For a sign pattern matrix A , if A 3=A , then A is said to be sign tripotent. In this paper, the characterization of the n by n(n... A matrix whose entries are +,-, and 0 is called a sign pattern matrix. For a sign pattern matrix A , if A 3=A , then A is said to be sign tripotent. In this paper, the characterization of the n by n(n≥2) sign pattern matrices A which are sign tripotent has been given out. Furthermore, the necessary and sufficient condition of A 3=A but A 2≠A is obtained, too. 展开更多
关键词 SIGN pattern matrix.
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Electromagnetic Field Released in Collision-Impact Events Generate in the Matrix Interface Fractal Scalable Invariant Geometric Triangular Chiral Hexagonal Structures 被引量:2
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作者 Jairo A. Diaz 《Open Journal of Geology》 2013年第3期187-200,共14页
In biology, cancer is the most beautiful natural model of a chaotic system, which under uncontrolled proliferations, generates extreme disorder that finally causes intercellular collisions. The authors have described ... In biology, cancer is the most beautiful natural model of a chaotic system, which under uncontrolled proliferations, generates extreme disorder that finally causes intercellular collisions. The authors have described and documented fractal self-assembly of geometric triangular chiral hexagonal crystal-like complex organizations (GTCHC) and interface comet tail effect patterns in cancer processes. According to this novel observation cancer incorporates a real visualization world with a great surprising finding in biology, physics, and geology. This visualization platform literally allows us to see what would otherwise remain completely invisible. From theory to practice this irreducible geometric matrix allowed us to identify in geology, real measurable green infrared-electromagnetic stripe line in interface with hexagonal geomorphic pattern, triangular chiral pyramidal rock structures, geology well defined mirror images, template platform to bio signature characterization of ancestral primitive polar head-tail organization, embryoid and human-like shape pattern embedded as giant fossils in rocks that have never been seen before. Electromagnetic field released in collision-impact events generate in the matrix interphase fractal scalable invariant order of geometric triangular chiral hexagonal structures. The laws of biology and geology can finally be redirected to the laws of physics;specifically magnetic fields create a new kind of classification based on these fractal structural similarities of the relationship. Further interdisciplinary collaboration must be carried out to study these geometric self-assembly geological structures, ancient sediments and rocks that could provide insights into antecedents of life. 展开更多
关键词 Electromagnetic Fields Geomorphic patterns IRREDUCIBLE GEOMETRIC matrix
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A complete compilation of matrix metalloproteinase expression in human malignant gliomas 被引量:19
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作者 Carsten Hagemann Jelena Anacker +1 位作者 Ralf-Ingo Ernestus Giles H Vince 《World Journal of Clinical Oncology》 CAS 2012年第5期67-79,共13页
Glioblastomas are characterized by an aggressive local growth pattern, a marked degree of invasiveness and poor prognosis. Tumor invasiveness is facilitated by the increased activity of proteolytic enzymes which are i... Glioblastomas are characterized by an aggressive local growth pattern, a marked degree of invasiveness and poor prognosis. Tumor invasiveness is facilitated by the increased activity of proteolytic enzymes which are involved in destruction of the extracellular matrix of the surrounding healthy brain tissue. Elevated levels of matrix metalloproteinases(MMPs) were found in glioblastoma(GBM) cell-lines, as well as in GBM biopsies as compared with low-grade astrocytoma(LGA) and normal brain samples, indicating a role in malignant progression. A careful review of the available literature revealed that both the expression and role of several of the 23 human MMP proteins is controversely discussed and for some there are no data available at all. We therefore screened a panel of 15 LGA and 15 GBM biopsy samples for those MMPs for which there is either no, very limited or even contradictory dataavailable. Hence, this is the first complete compilation of the expression pattern of all 23 human MMPs in astrocytic tumors. This study will support a better understanding of the specific expression patterns and interaction of proteolytic enzymes in malignant human glioma and may provide additional starting points for targeted patient therapy. 展开更多
关键词 Astrocytic tumor EXPRESSION pattern GLIOBLASTOMA CELL-LINES GLIOBLASTOMA MULTIFORME matrix METALLOPROTEINASE
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INERTIA SETS OF SYMMETRIC SIGN PATTERN MATRICES
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作者 Frank J.Hall +1 位作者 Li 李忠尚 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2001年第2期226-240,共15页
A sign pattern matrix is a matrix whose entries are from the set {+,-,0}. The symmetric sign pattern matrices that require unique inertia have recently been characterized. The purpose of this paper is to more generall... A sign pattern matrix is a matrix whose entries are from the set {+,-,0}. The symmetric sign pattern matrices that require unique inertia have recently been characterized. The purpose of this paper is to more generally investigate the inertia sets of symmetric sign pattern matrices. In particular, nonnegative tri-diagonal sign patterns and the square sign pattern with all + entries are examined. An algorithm is given for generating nonnegative real symmetric Toeplitz matrices with zero diagonal of orders n≥3 which have exactly two negative eigenvalues. The inertia set of the square pattern with all + off-diagonal entries and zero diagonal entries is then analyzed. The types of inertias which can be in the inertia set of any sign pattern are also obtained in the paper. Specifically, certain compatibility and consecutiveness properties are established. 展开更多
关键词 inertia SIGN pattern matrix INERTIA set UNIQUE inertia TOEPLITZ matrix.
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ELECTRON DIFFRACTION PATTERNS ANALYSIS OF PRECIPITATES IN LD_(10) ALLOY
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作者 Jin, Tounan Yin, Zhimin(Department of Materials Science and Engineering,Central South University of Technology, Changsha 410083) 《中国有色金属学会会刊:英文版》 CSCD 1995年第3期119-123,共5页
ELECTRONDIFFRACTIONPATTERNSANALYSISOFPRECIPITATESINLD_(10)ALLOY¥Jin,Tounan;Yin,Zhimin(DepartmentofMaterialsS... ELECTRONDIFFRACTIONPATTERNSANALYSISOFPRECIPITATESINLD_(10)ALLOY¥Jin,Tounan;Yin,Zhimin(DepartmentofMaterialsScienceandEngineer?.. 展开更多
关键词 PRECIPITATE SIMULATED DIFFRACTION pattern TRANSFORMATION matrix
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LANDSCAPE PATTERN CHANGES IN WEST SUBURBS OF SHENYANG
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作者 肖笃宁 赵羿 郭林海 《Chinese Geographical Science》 SCIE CSCD 1994年第3期277-288,共12页
Spatial pattern of landscape is a central issue in landscape ecology study. The main reason of landscape patten change owes to the external disturbance. In this article, retrospective sequential airphotoanalysis and s... Spatial pattern of landscape is a central issue in landscape ecology study. The main reason of landscape patten change owes to the external disturbance. In this article, retrospective sequential airphotoanalysis and statistical analysis of information on landscape development were used and two remarkable changes of landscape pattern in west Shenyang were identified: (a) one landscape element becomes a new matrix in place of the former one; (b) landscape proportions among several constiting elements changed significantly. This paper studied spatial pattern of the landscape using following quanta indices: (1) number and size of patches, (2) transition matrix of patches, (3) priority index of each kind of patch and (4) diversity and evenness indices of landscape.The results show that the landscape of west Shenyang has been more and more disturbed by human activities, so it becomes fragmentary throughout 30 years, and many blocky and island-like patches emerged. 展开更多
关键词 SUBURB LANDSCAPE spatial pattern PRIORITY index transition matrix human DISTURBANCE
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Analysis of Land Cover and Landscape Pattern Change in Beijing-Tianjin-Hebei Region Based on Globeland30 Data
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作者 Yimeng Shi Hongli Song +2 位作者 Ming Shang Mingchao Shao Haimei Lei 《Journal of Geographic Information System》 2020年第3期241-255,共15页
With the rapid economic development and urbanization process in Beijing-Tianjin-Hebei region, land use and landscape pattern have been changed. In order to reveal the temporal and spatial changes and provide scientifi... With the rapid economic development and urbanization process in Beijing-Tianjin-Hebei region, land use and landscape pattern have been changed. In order to reveal the temporal and spatial changes and provide scientific basis for the local land use planning and landscape pattern optimization made by government, based on the classification results of Globeland 30 land cover data in 2000 and 2010, this paper quantitatively analyzed the land use transfer status and the dynamic change of landscape pattern in Beijing-Tianjin-Hebei by adopting the method of land use transfer matrix and landscape index. The results show that the land use and landscape patterns in Beijing-Tianjin-Hebei have been changed significantly from 2000 to 2010. Overall, land use in Beijing-Tianjin-Hebei region has been changed greatly, which shows that the cultivated land area has been decreased by 3721.67 km<sup>2</sup>, while the artificial surface area and grassland area have increased by 2721.29 km<sup>2</sup> and 657.09 km<sup>2</sup>, respectively. From the six partitions of Beijing-Tianjin-Hebei, it can be seen that the subareas with significant changes are Sand Control Farmland Protection Zone in Yellow River Flood Plain, Water Conservation Area for Sand Control in Mountain and Hilly Areas of Northwest Taihang Mountains, and Human Settlement Environment Maintenance and Farmland Protection Zone of Beijing-Tianjin-Hebei Urban Agglomeration. The arable land area of these three zones has decreased 572.77 km<sup>2</sup>, 1553.94 km<sup>2</sup> and 1359.53 km<sup>2</sup>, respectively. From the perspective of landscape pattern change, patch density and fragmentation degree in the southeast and northwest of Beijing-Tianjin-Hebei region increase;and the dominant patches in the southeast of Beijing-Tianjin-Hebei region have formed a good connectivity;the whole Beijing-Tianjin-Hebei region shows irregular shape and discontinuous enhancement of landscape types, the landscape patch types increase and enrich, and the dominance shows a downward trend. 展开更多
关键词 Land Use Transfer matrix Landscape pattern Landscape Index Globeland30
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Landscape pattern change of a typical region in the Kubuqi Desert, Northwestern China
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作者 CUI Bu-li CHANG Xue-li LI Xiao-yan 《地球环境学报》 2012年第6期1165-1173,共9页
Spatial pattern analysis is the core component in landscape ecology research.We analyzed the landscape pattern and dynamic process of the Kubuqi Desert by using a typical region as a study area.This study area include... Spatial pattern analysis is the core component in landscape ecology research.We analyzed the landscape pattern and dynamic process of the Kubuqi Desert by using a typical region as a study area.This study area includes four towns;ShuLinZhao,WangAiZhao,BaiNiJing and JiGeSiTai.The area of cropland,fixed sand dune,woodland,residential area and wetland increased and centralized gradually,while the area of semi-fixed sand dune,drifting sand dune,meadow and washland decreased and dispersed gradually from 1987 to 2003.On the landscape level,the patch shape tended to be regular,and the landscape pattern tended to be simple,causing the fragmentation degree,heterogeneity and diversity of the landscape to decrease.Fixed sand dune.Semi-fixed sand dune,drifting sand dune,meadow and river flood plains were the five main export classes,and residential area,cropland and wetland were the three main import classes.The classes that had a relatively large total area and large average patch area had a smaller extent of gravity center migration,whereas the classes with small total area and small average patch area had a larger extent of gravity center migration;this is because the small patches are easily influenced by human activities or natural factors.In addition,the desertification area and desertification degree reduced gradually in the study area during the period from 1987 to 2003. 展开更多
关键词 Landscape pattern gravity center migration transfer matrix landscape index the Kubuqi Desert
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基于ChaffMatrix的光载声音声纹变化识别系统设计
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作者 白曦龙 冯佳 《激光杂志》 CAS 北大核心 2022年第1期174-178,共5页
采集光载声音时会受到激光传输信道噪声的干扰,传统声纹变化识别系统对于信道噪声的去噪效果不好,影响最终的声纹识别准确性,因此,设计一种基于ChaffMatrix的光载声音声纹变化识别系统。系统沿用传统系统的硬件设计,主要对于软件方面进... 采集光载声音时会受到激光传输信道噪声的干扰,传统声纹变化识别系统对于信道噪声的去噪效果不好,影响最终的声纹识别准确性,因此,设计一种基于ChaffMatrix的光载声音声纹变化识别系统。系统沿用传统系统的硬件设计,主要对于软件方面进行详细研究。首先对一段语音端点进行检测,采用单门限阈值法来检测能量端点,排除噪声优化计算量,提高检测准确度,设计基于ChaffMatrix的声纹模板转换成伪矩阵的音频信号尺度来反映频谱系数的频率范围,作为系统后端识别部分的输入,最后通过改变人工神经网络的结构来优化声纹识别算法,将原有的单层结构改变成多层结构,模拟生物神经元的互联过程,完成声纹降噪。仿真实验的结果表明,设计的系统相对于ANN-VQ系统、CS算法系统、改进谱减法系统三个原有系统来说,具有更好的去噪性能。 展开更多
关键词 光载声音 声纹变化识别 系统设计 伪矩阵
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基于RSCM与黎曼空间的运动想象脑电分类研究 被引量:1
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作者 廉小亲 刘春权 +2 位作者 高超 邓子谦 吴叶兰 《电子测量技术》 北大核心 2025年第9期84-93,共10页
近年来,运动想象(MI)在辅助医疗和人机交互领域备受关注。然而,经典的共空间模式(CSP)特征提取方法主要基于时域信号计算协方差矩阵(CM),易受噪声和伪迹干扰,且无法充分利用脑电信号(EEG)的频谱信息,导致分类精度与稳定性不足。为了解... 近年来,运动想象(MI)在辅助医疗和人机交互领域备受关注。然而,经典的共空间模式(CSP)特征提取方法主要基于时域信号计算协方差矩阵(CM),易受噪声和伪迹干扰,且无法充分利用脑电信号(EEG)的频谱信息,导致分类精度与稳定性不足。为了解决这一问题,本研究提出了一种基于正则化频谱协方差矩阵(RSCM)与黎曼空间的MI-EEG分类算法。首先,对预处理后的EEG信号进行快速傅里叶变换,计算频谱协方差矩阵,并进行岭正则化;然后,将正则化矩阵映射到切空间中进行平滑滤波,并将结果映射回黎曼空间以提取CSP特征;最后,采用支持向量机(SVM)完成分类任务。实验结果表明,在BCI竞赛IV数据集1和2a上,本研究方法的二分类平均准确率分别达到了86.95%和81.48%,较传统CSP分别提升了7.44%和9.57%;在BCI竞赛IV数据集2a上,本研究方法的四分类平均准确率达到了74.23%,较传统CSP方法提升了14.10%。实验结果表明,本研究方法在MI-EEG分类中具有有效性。 展开更多
关键词 运动想象 脑电信号 频谱协方差矩阵 黎曼空间 共空间模式
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Assessment of Structural Damage Condition Based on Fuzzy Pattern Recognition
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作者 WU Zi-yan ZHANG Yu 《International Journal of Plant Engineering and Management》 2008年第1期10-19,共10页
This paper presents a new method of damage condition assessment that allows accommodating other types of uncertainties due to ambiguity, vagueness, and fuzziness that are statistically nondescribable. In this method, ... This paper presents a new method of damage condition assessment that allows accommodating other types of uncertainties due to ambiguity, vagueness, and fuzziness that are statistically nondescribable. In this method, healthy observations are used to construct a fury set representing sound performance characteristics. Additionally, the bounds on the similarities among the structural damage states are prescribed by using the state similarity matrix. Thus, an optimal group fuzzy sets representing damage states such as little, moderate, and severe damage can be inferred as an inverse problem from healthy observations only. The optimal group of damage fuzzy sets is used to classify a set of observations at any unknown state of damage using the principles of fitzzy pattern recognition based on an approximate principle . This method can be embedded into the system of Structural Health Monitoring (SHM) to give advice about structural maintenance and life predictio comes from Reference [ 9 ] for damage pattern recognition is presented n. Finally, a case and discussed. The study, which compared result illustrates our method is more effective and general, so it is very practical in engineering. 展开更多
关键词 damage condition assessment fuzzy pattern recognition state similarity matrix approximate principle structural health monitoring
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结合论文施引特征和分布式检索技术的引文耦合度算法设计
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作者 郭锐锋 常志军 +3 位作者 董美 张建勇 钱力 董智鹏 《小型微型计算机系统》 北大核心 2025年第2期297-304,共8页
大规模科技文献知识库的全量引文耦合关系因计算量巨大的难题,阻碍了引文耦合知识服务在诸多业务场景的应用.本文提出了一种适用于大规模文献知识库的全量引文耦合度计算算法,根据施引特征过滤没有耦合关系的无效组合,避免计算过程中稀... 大规模科技文献知识库的全量引文耦合关系因计算量巨大的难题,阻碍了引文耦合知识服务在诸多业务场景的应用.本文提出了一种适用于大规模文献知识库的全量引文耦合度计算算法,根据施引特征过滤没有耦合关系的无效组合,避免计算过程中稀疏矩阵的产生,并引入多模式匹配技术,优化算法的整体时间复杂度为O(n log z).本算法在生产环境中依赖分布式搜索引擎集群完成工程化实施.在国家科技图书文献中心的3600万篇科技文献数据库上,对该方法与传统引文耦合方法进行了多组实验对比,并生成了6.59亿论文对的耦合度数据,为国家科技图书文献中心的引文耦合知识服务提供了数据支持,验证了该方法的准确性和实用性. 展开更多
关键词 引文耦合度 分布式搜索引擎 稀疏矩阵 施引特征 多模式匹配
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Study on the Seismogeny and Occurrence of Earthquakes by Using Pattern Dynamics
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作者 Lan Congxin Xu Ping 《Earthquake Research in China》 2000年第3期42-52,共11页
The mesoscopic damage dynamics and damage evolution have been applied to probe theevolutional process induced catastrophe in the earthquake activity.It is a new method.In thispaper,a brief introduction of the basic pr... The mesoscopic damage dynamics and damage evolution have been applied to probe theevolutional process induced catastrophe in the earthquake activity.It is a new method.In thispaper,a brief introduction of the basic principle about damage dynamics and evolution ismade.At the same time,using the theory of the pattern dynamics we studied all earthquakes(M_L≥5.0)which occurred along Zhangjiakou-Bohai Sea earthquake belt in the capitalregion.The result indicates that the preparation and happening of the real earthquakes andthe theory are consistent.There are two kinds of evolutional model according to the finalstate,namely,global stability model(GS)and evolution induced catastrophe model(EIC).The two models haven’t evident boundary.The transitional zone exhibits the indeterminacyof the seismic process and the effect of the random variation.This research proposed newapproaches for earthquake prediction. 展开更多
关键词 MACROSCOPIC damage evolution pattern dynamics Zhangjiakou-Bohai Sea earthquake belt Evolutional matrix
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东方蜜蜂基质金属蛋白酶14基因AcMMP 14的分子特征与表达模式 被引量:2
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作者 刘治滩 叶道有 +8 位作者 宓诗雨 王宁 郑一荻 蒋海宾 吴鹰 徐细建 陈大福 邱剑丰 郭睿 《昆虫学报》 北大核心 2025年第3期282-290,共9页
【目的】本研究旨在克隆东方蜜蜂Apis cerana基质金属蛋白酶14(matrix metalloproteinase-14,MMP14)基因AcMMP 14,分析其分子特征和表达模式,为持续深入开展AcMMP 14的功能研究提供参考和依据。【方法】提取东方蜜蜂6日龄工蜂幼虫肠道总... 【目的】本研究旨在克隆东方蜜蜂Apis cerana基质金属蛋白酶14(matrix metalloproteinase-14,MMP14)基因AcMMP 14,分析其分子特征和表达模式,为持续深入开展AcMMP 14的功能研究提供参考和依据。【方法】提取东方蜜蜂6日龄工蜂幼虫肠道总RNA,PCR扩增AcMMP 14的编码序列(coding sequence,CDS)。使用相关生物信息学软件预测AcMMP14的理化性质和分子特征,鉴定东方蜜蜂和其他蜂种MMP14的结构域和保守基序,并进行系统进化分析。采用RT-qPCR检测AcMMP 14在工蜂卵、幼虫、预蛹、蛹和不同日龄成虫,工蜂成虫触角、脑、表皮、脂肪体、毒腺、中肠和咽下腺及东方蜜蜂微孢子虫Nosema ceranae接种刚出房的1日龄工蜂后1-4 d时中肠中的相对表达量。【结果】AcMMP14的分子式为C 3068 H 4581 N 803 O 915 S 20,分子量约为68.00 kD,脂溶系数为64.12,等电点为5.85,平均亲水系数为-0.47,含1个信号肽和36个磷酸化位点,可同时定位于线粒体、细胞核和细胞质。东方蜜蜂与其他10种蜂的MMP14中均含有3个相同的结构域和5个相同的保守基序。东方蜜蜂与大蜜蜂A.dorsata的MMP14的氨基酸序列一致性达94.23%,且在进化树上聚为一支。AcMMP 14在东方蜜蜂工蜂卵、3日龄幼虫、1和2日龄预蛹及4日龄蛹中差异表达,在4日龄蛹中的表达量最高且显著高于3日龄幼虫和2日龄预蛹中的表达量。AcMMP 14在不同日龄工蜂成虫体内差异表达,在15日龄成虫体内的表达量最高且显著高于1,2,6,12和17日龄成虫体内的表达量。AcMMP 14在东方蜜蜂工蜂成虫的7种不同组织中差异表达,在触角中的表达量最高且显著高于脑、表皮、脂肪体、毒腺、中肠和咽下腺中的表达量。与未接种的对照组相比,东方蜜蜂微孢子虫接种后1和2 d时工蜂成虫中肠中AcMMP14的表达量显著下调,3和4 d时工蜂成虫中肠中AcMMP14的表达量下调但差异不显著。【结论】AcMMP14为潜在的亲水性蛋白和分泌蛋白;AcMMP 14在东方蜜蜂工蜂不同发育阶段和成虫组织中发挥潜在的重要功能;工蜂成虫中肠中AcMMP 14在东方蜜蜂微孢子虫的第一个增殖周期前期被激活表达。 展开更多
关键词 东方蜜蜂 基质金属蛋白酶 东方蜜蜂微孢子虫 表达模式 分子特征
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传统纺织品图案的屈曲矫正与再生设计 被引量:2
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作者 石文慧 朱海峰 +2 位作者 蒋汶秦 倪嘉陆 徐平华 《服装学报》 北大核心 2025年第1期40-45,共6页
为解决传统纺织品成像屈曲造成的图案变形问题,探究基于内容的图像拉伸方法,同时对矫正后的图案进行再生设计。通过计算图像的能量矩阵得到端到端的最小能量曲线,利用周边信息计算出填补像素;通过路径动态规划的迭代来实现图像在水平和... 为解决传统纺织品成像屈曲造成的图案变形问题,探究基于内容的图像拉伸方法,同时对矫正后的图案进行再生设计。通过计算图像的能量矩阵得到端到端的最小能量曲线,利用周边信息计算出填补像素;通过路径动态规划的迭代来实现图像在水平和垂直方向上的内容填充,从而实现屈曲图像的矫正。利用边缘检测、矢量化操作和颜色聚类等方法,对纹样和色彩进行再生设计。将基于能量矩阵矫正图案屈曲的方法与其他常用的形态矫正算法进行对比。结果表明,基于能量矩阵矫正图案屈曲的方法在保全内容的前提下,能够有效实现屈曲图案的形态矫正。借助图像处理技术,可以提取矫正后图案的纹样和色彩,应用于当代产品创新设计。 展开更多
关键词 传统图案 屈曲 矫正 色彩提取 能量矩阵
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