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基于颜色不变特征的谱聚类双分图分割方法 被引量:1
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作者 赵薇 赵娜 张怡兴 《信息网络安全》 CSCD 北大核心 2018年第12期8-14,共7页
谱聚类分割方法的结果很大程度上受超像素分类聚合效果的影响,而超像素分类聚合的效果关键在于超像素之间的相似性模型。基于双分图的分割框架利用交叉相似性矩阵可以高效完成超像素分类聚合,但其相似性模型采用简单的颜色特征,对强光... 谱聚类分割方法的结果很大程度上受超像素分类聚合效果的影响,而超像素分类聚合的效果关键在于超像素之间的相似性模型。基于双分图的分割框架利用交叉相似性矩阵可以高效完成超像素分类聚合,但其相似性模型采用简单的颜色特征,对强光照射、遮蔽等光照变化不具有鲁棒性,影响目标分割的精度。为了提高超像素聚合的一致性,文章提出利用具有颜色不变特征的颜色描述子和能够反映物理表面反射变化的Ridge特征来构建交叉相似性模型。在Berkeley分割数据集中的实验验证,基于颜色不变特征的谱聚类分割方法获得了比已有分割算法更好的效果。 展开更多
关键词 谱聚类 超像素 双分图分割 颜色不变性
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K方图的若干性质
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作者 王应前 《安庆师范学院学报(自然科学版)》 1996年第4期74-75,共2页
本文证明K方图是一个双分K正则Hamilton图,同时分析了它的顶点数、边数和最短圈数。
关键词 K方 双分图 HAMILTON 顶点数 边数
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关于色多项式的若干注记
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作者 王志雄 《华侨大学学报(自然科学版)》 CAS 1993年第4期412-418,共7页
给出若干类型多项式为简单图的色多项式的充分必要条件、连通图和连通双分图的色多项式必须满足的条件,研究图及其补图的色多项式对图特征的描述程度,并提出若干值得进一步探讨的问题。
关键词 色多项式 连通 双分图
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Evolution of Main Characteristics of the Registered Cotton Cultivars in National Cotton Regional Trials in Yangtze River Valley 被引量:1
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作者 许乃银 李健 《Agricultural Science & Technology》 CAS 2014年第6期964-969,共6页
[Objective] The aim of this study was to characterize the national regis- tered varieties selected from cotton regional trials in Yangtze River Valley (YaRV) in recent years. [Method] Cotton cultivar classification ... [Objective] The aim of this study was to characterize the national regis- tered varieties selected from cotton regional trials in Yangtze River Valley (YaRV) in recent years. [Method] Cotton cultivar classification and comprehensive evaluation index were set up based on national cotton registration standard. GGE biplot method was adopted to analyze the correlation of major breeding target characters of 53 national registered cotton varieties in cotton regional trials in YaRV during 1981-2012. According to the shift of check cultivars in cotton regional trials in the past, the cotton regional trial practice since 1981 was divided into five periods. The dynamic of cultivar type's proportion and the evaluation index scores was analyzed across the five periods. [Result] There existed intricate interrelationship among cotton breeding target traits, which constrained it necessary to construct indices for com- prehensive evaluation of cotton varieties. The dynamic of cultivar types in the five periods indicated that type II varieties emerged since Simian 3 period and then its proportion decreased gradually; type Ⅲ varieties maintained a certain proportion in each period and kept on the rise overall; type Ⅳvarieties occupied the majority pro- portion of registered cultivars before 1993, but a minor proportion since Simian 3 period. On the other side, the change trend of the evaluation index demonstrated that the varieties registered before 2003 did not pass the qualified line at present. The peak scores appeared in the varieties registered during 2004-2008. The scores of the varieties registered after 2009 were only slightly over the qualified line. [Conclusion] More attention should be paid to the improvement and evaluation of micronaire, so as to guide the simultaneous development of high yielding and fiber quality in cotton breeding and registration procedure in YaRV. 展开更多
关键词 Cotton (Gossypium hirsutum L.) GGE biplot Variety type classification The Yangtze River Valley (YaRV)
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Electrophoresis Analysis on the Protein Expression in Heteromorphic Leaves of Populus euphratica Oliv. 被引量:1
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作者 岳宁 郑彩霞 Cai-xia 《Agricultural Science & Technology》 CAS 2010年第5期41-45,共5页
[Objective] This study was to elucidate the cellular and molecular mechanism of the development of heteromorphic leaves of Populus euphratica Oliv. [Method] By employing SDS-PAGE and 2-demensional electrophoresis (2-D... [Objective] This study was to elucidate the cellular and molecular mechanism of the development of heteromorphic leaves of Populus euphratica Oliv. [Method] By employing SDS-PAGE and 2-demensional electrophoresis (2-DE) techniques,proteins in various heteromorphic leaves from the same adult tree of P. euphratica were isolated and separated to the electrophoresis technique suitable for the separation and analysis of proteins in leaves of P. euphratica tree. [Results] There were significant differences in the expressions of proteins in various heteromorphic leaves of P. euphratica tree. SDS-PAGE pattern showed that bands of proteins with molecular weight of 57.2,13.2,30.2,23.9 and 33.3 kDa were remarkably different. 2-D electrophoresis pattern presented that proteins in leaves of P. euphratica tree mainly belong to acidic proteins distributed at pH value of 5.0-6.5 and with molecular weight of 20-40 kDa; totally 73 different protein spots were observed,of which 51 were up expressed and other 22 were down expressed in the serrated ovate leaves. [Conclusion] Based on these results,we speculate that regulated gene expression in leaves of P. euphratica tree results in the generation of different shapes of leaves,in order to adapt to the surroundings better. 展开更多
关键词 Populus euphratica Oilv. Heteromorphic leaves SDS-PAGE 2-demensional electrophoresis
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An Ocular Artifacts Removal Method Based on Canonical Correlation Analysis and Two-Channel EEG Recordings 被引量:1
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作者 XIE Jin QIU Tian-shuang LIU Wen-hong 《Chinese Journal of Biomedical Engineering(English Edition)》 2012年第2期60-66,共7页
In order to more effectively apply an artifact removal melhod in an online brain-computer interface (BCI) system, a new method based on canonical correlation analysis (CCA) and two-channel eleetroeneephalography ... In order to more effectively apply an artifact removal melhod in an online brain-computer interface (BCI) system, a new method based on canonical correlation analysis (CCA) and two-channel eleetroeneephalography (EEG) recordings to quickly remove ocular artifacts (OA) is proposed in this paper. Considering both the formation of EEG signals contaminated by OA and the spread of OA, vertical electrooculo~'aphy (VEOG) was appropriately introduced in CCA, and the blind source separation (BSS~ method based on CCA was used in a new way during the OA removal process. Both experimental and comparison with ICA and SOBI results show that the new method with simple calculation and fast processing speed can effectively separate and remove OA using only two-channel EEG recordings, with retaining useful EEG signals. Hence, this method used in an online BCI system will be more effective. 展开更多
关键词 CCA two-channel EEG recordings OA VEOG an online BCI system
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Exact Solutions to a (3+1)-Dimensional Variable-Coefficient Kadomtsev-Petviashvilli Equation via the Bilinear Method and Wronskian Technique
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作者 ZHANG Chcng TIAN Bo +4 位作者 XU Tao LI Li-Li Lü Xing GENG Tao ZHU Hong-Wu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第9期468-472,共5页
By truncating the Painleve expansion at the constant level term,the Hirota bilinear form is obtainedfor a (3+1)-dimensional variable-coefficient Kadomtsev-Petviashvili equation.Based on its bilinear form,solitary-wave... By truncating the Painleve expansion at the constant level term,the Hirota bilinear form is obtainedfor a (3+1)-dimensional variable-coefficient Kadomtsev-Petviashvili equation.Based on its bilinear form,solitary-wavesolutions are constructed via the ε-expansion method and the corresponding graphical analysis is given.Furthermore,the exact solution in the Wronskian form is presented and proved by direct substitution into the bilinear equation. 展开更多
关键词 (3+1)-dimensional variable-coefficient Kadomtsev-Petviashvili equation Wronskian solution bilinear form exact solution
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Bilayer self-assembly on a hydrophilic, deterministically nanopatterned surface
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作者 Gregory S. Smith Seung-Yong Jung +4 位作者 James F. Browning Jong K. Keum Nickolay V. Lavrik Mussie G. Alemseghed C. Patrick Collier 《Nano Research》 SCIE EI CAS CSCD 2013年第11期784-794,共11页
We present measurements of the in situ, microscopic architecture of a self- assembled bilayer at the interface between a regularly nanopatterned surface and an aqueous sub-phase using neutron reflectometry. The substr... We present measurements of the in situ, microscopic architecture of a self- assembled bilayer at the interface between a regularly nanopatterned surface and an aqueous sub-phase using neutron reflectometry. The substrate is patterned with a rectangular array of nanoscale holes. Because of the high quality of the pattern, using neutron reflectometry, we are able to map the surface-normal density distribution of the patterned silicon, the penetration of water into the pattern, and the distribution of a deposited film inside and outside of the etched holes. In this stud; 1,2-dilauroyl-sn-glycero-3-phosphocholine (DLPC) single bilayers were deposited on the hydrophilic patterned surface. For bilayers deposited either by vesicle fusion (VF) or by the Langmuir-Schaefer (L-S) technique, the most consistent model found to fit the data shows that the lipids form bilayer coatings on top of the substrate as well as the bottoms of the holes in an essentially conformal fashion. However, while there is a single bilayer on the unetched silicon surface, the lipids coating the bottoms of the holes form a complex bimodal structure consistent with a rough surface produced by the etching process. This study provides insight into film transfer both outside and inside regular nanopatterned features. 展开更多
关键词 thin film NANOPATTERN neutron reflectivity LIPID SELF-ASSEMBLY
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Super-resolution acoustic image montage via a biaxial metamaterial lens
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作者 Yu-Gui Peng Ya-Xi Shen +3 位作者 Zhi-Guo Geng Peng-Qi Li Jie Zhu Xue-Feng Zhu 《Science Bulletin》 SCIE EI CAS CSCD 2020年第12期1022-1029,M0004,共9页
Ever since the Victorian era, montage, the process of pictorial composition made by juxtaposing or superimposing photographs, has been a very popular post-editing imaging technique. Despite showing a strong power in d... Ever since the Victorian era, montage, the process of pictorial composition made by juxtaposing or superimposing photographs, has been a very popular post-editing imaging technique. Despite showing a strong power in demonstrating complex wave field effects, this technique has neither been fully explored in acoustic imaging nor been realized in real-time systems with the capability beyond diffraction limits.On the other hand, the recent prospect of metamaterials has shown their great potentials in superresolution acoustic imaging. However, the miracle jigsaw of more advanced functional modulation of acoustic wave fields at deep subwavelength scale still remains elusive. Here we report the experimental implementation of super-resolution acoustic image montage through a judiciously designed biaxial metamaterial lens. Based on the non-diffraction birefringence in the biaxial metamaterials, we realized various montage functionalities such as duplication, composition, and decomposition of sound images with distinctive deep subwavelength features. Our work represents an important step in developing versatile functional acoustic metamaterial devices for imaging purposes, as it provides on-demand editing of sound field patterns beyond diffraction limits. 展开更多
关键词 Acoustic metamaterials Super-resolution imaging Biaxial metamaterials Montage technique
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