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Morphological analysis for thermodynamics of cavitation collapse near fractal solid wall
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作者 单鸣雷 杨雨 +2 位作者 阚雪芬 殷澄 韩庆邦 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期422-432,共11页
A fractal geometric boundary with natural wall features is introduced into a hybrid lattice-Boltzmann-method(LBM)multiphase model. The physical model of cavitation bubble collapse near the irregular geometric wall is ... A fractal geometric boundary with natural wall features is introduced into a hybrid lattice-Boltzmann-method(LBM)multiphase model. The physical model of cavitation bubble collapse near the irregular geometric wall is established to study the thermodynamic characteristics of the bubble collapse. Due to the lack of periodicity, symmetry, spatial uniformity and obvious correlation in the LBM simulation of the bubble collapse near the fractal wall, the morphological analysis based on Minkowski functional is introduced into the thermodynamic investigation of cavitation bubble so as to analyze and obtain the effective information. The results show that the Minkowski functional method can employed to study the temperature information in complex physical fields hierarchically and quantitatively. The high/low temperature region of the cavitation flow is explored, and thermal effect between irregular and fractal geometric wall and cavitation bubble can be revealed. It illustrates that LBM and morphological analysis complement each other, and morphological analysis can also be used as an optional and potential tool in research field of complex multiphase flows. 展开更多
关键词 lattice Boltzmann method cavitation bubble morphological analysis
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Korean Morphological Analysis for Korean-Vietnamese Statistical Machine Translation
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作者 Quang-Phuoc Nguyen Joon-Choul Shin Cheol-Young Ock 《Journal of Electronic Science and Technology》 CAS CSCD 2017年第4期413-419,共7页
This paper describes the experiments with Korean-to-Vietnamese statistical machine translation(SMT). The fact that Korean is a morphologically complex language that does not have clear optimal word boundaries causes a... This paper describes the experiments with Korean-to-Vietnamese statistical machine translation(SMT). The fact that Korean is a morphologically complex language that does not have clear optimal word boundaries causes a major problem of translating into or from Korean. To solve this problem, we present a method to conduct a Korean morphological analysis by using a pre-analyzed partial word-phrase dictionary(PWD).Besides, we build a Korean-Vietnamese parallel corpus for training SMT models by collecting text from multilingual magazines. Then, we apply such a morphology analysis to Korean sentences that are included in the collected parallel corpus as a preprocessing step. The experiment results demonstrate a remarkable improvement of Korean-to-Vietnamese translation quality in term of bi-lingual evaluation understudy(BLEU). 展开更多
关键词 Factored translation models Korean-Vietnamese parallel corpus morphological analysis statistical machine translation(SMT)
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The Morphological Analysis of Folktales of Tu Nationality in Hehuang Region in Northwest China
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作者 ZHAO Zhi-yi 《Journal of Literature and Art Studies》 2016年第11期1293-1303,共11页
The Tu nationality (also called "Tu people" or "Tus" in the paper), one of the multiple ethnic minorities in the Hehuang Region (河湟地区) between Gansu (甘肃) and Qinghai (青海) Provinces in the northwest... The Tu nationality (also called "Tu people" or "Tus" in the paper), one of the multiple ethnic minorities in the Hehuang Region (河湟地区) between Gansu (甘肃) and Qinghai (青海) Provinces in the northwest China, has no written language of their own, but has already created the abundant and varied colorful literary genres. Since the 1980s, folktales, as the main literary product popular in the region, have received literary criticisms and reviews from scholars and researchers in China, based on the socialist realism dominant in China in the 20th century that emphasized more on contents, motifs and even ideological significance. So far, no breakthroughs have been made in their studies even if some young scholars have tried from the formalist viewpoints. Therefore, this paper attempts to make a morphological analysis of the Tus' folktales by adopting Propp's theories, trying to find out the morphological narrative model beneath the language level of the folktales. Through the studies, we can see that collective awareness bonded by kinship is more emphasized in Tus' culture, and almost all tales end with good defeating evil. Therefore, the studies of these folktales will help us deep understand Tus' psychological conditions and positive cultural life. 展开更多
关键词 morphological analysis folktales of Tu nationality Hehuang Region Propp's theory creative rules collectiveness
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Application of the Morphological Analysis for the Synthesis Arrangements of Industrial Robots with Parallel Structure Mechanisms
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作者 Ibrahim Farhan Salman Alrefo 《Modern Mechanical Engineering》 2016年第2期60-66,共7页
The main features of morphological model of industrial robots are discussed, such as support system, manipulator and gripping device. These features are presented with the alternatives for their realization as separat... The main features of morphological model of industrial robots are discussed, such as support system, manipulator and gripping device. These features are presented with the alternatives for their realization as separate modules. The examples of synthesis of arrangements of industrial robots are resulted on module principle with writing of their morphological formulas. 展开更多
关键词 morphological analysis Industrial Robot Arrangement Module Principle Mechanism of Parallel Structure
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Wind turbine clutter mitigation using morphological component analysis with group sparsity
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作者 WAN Xiaoyu SHEN Mingwei +1 位作者 WU Di ZHU Daiyin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第3期714-722,共9页
To address the problem that dynamic wind turbine clutter(WTC)significantly degrades the performance of weather radar,a WTC mitigation algorithm using morphological component analysis(MCA)with group sparsity is studied... To address the problem that dynamic wind turbine clutter(WTC)significantly degrades the performance of weather radar,a WTC mitigation algorithm using morphological component analysis(MCA)with group sparsity is studied in this paper.The ground clutter is suppressed firstly to reduce the morphological compositions of radar echo.After that,the MCA algorithm is applied and the window used in the short-time Fourier transform(STFT)is optimized to lessen the spectrum leakage of WTC.Finally,the group sparsity structure of WTC in the STFT domain can be utilized to decrease the degrees of freedom in the solution,thus contributing to better estimation performance of weather signals.The effectiveness and feasibility of the proposed method are demonstrated by numerical simulations. 展开更多
关键词 weather radar wind turbine clutter(WTC) morphological component analysis(MCA) short-time Fourier transform(STFT) group sparsity
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Ground-roll separation of seismic data based on morphological component analysis in twodimensional domain 被引量:2
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作者 徐小红 屈光中 +2 位作者 张洋 毕云云 汪金菊 《Applied Geophysics》 SCIE CSCD 2016年第1期116-126,220,共12页
Ground roll is an interference wave that severely degrades the signal-to-noise ratio of seismic data and affects its subsequent processing and interpretation.In this study,according to differences in morphological cha... Ground roll is an interference wave that severely degrades the signal-to-noise ratio of seismic data and affects its subsequent processing and interpretation.In this study,according to differences in morphological characteristics between ground roll and reflected waves,we use morphological component analysis based on two-dimensional dictionaries to separate ground roll and reflected waves.Because ground roll is characterized by lowfrequency,low-velocity,and dispersion,we select two-dimensional undecimated discrete wavelet transform as a sparse representation dictionary of ground roll.Because of a strong local correlation of the reflected wave,we select two-dimensional local discrete cosine transform as the sparse representation dictionary of reflected waves.A sparse representation model of seismic data is constructed based on a two-dimensional joint dictionary then a block coordinate relaxation algorithm is used to solve the model and decompose seismic record into reflected wave part and ground roll part.The good effects for the synthetic seismic data and application of real seismic data indicate that when using the model,strong-energy ground roll is considerably suppressed and the waveform of the reflected wave is effectively protected. 展开更多
关键词 Ground-roll suppression morphological component analysis sparse representation two-dimensional undecimated discrete wavelet transform two-dimensional local discrete cosine transform
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Morphological and mechanical analysis of natural marble joints submitted to shear tests
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作者 M.Gasc-Barbier T.T.N.Hoang +2 位作者 A.Marache J.Sulem J.Riss 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2012年第4期296-311,共16页
In order to evaluate the influence of the surface morphology on the mechanical behavior of twelve natural marble joints, very accurate topography measurements of joint surfaces under constant normal load (CNL) condi... In order to evaluate the influence of the surface morphology on the mechanical behavior of twelve natural marble joints, very accurate topography measurements of joint surfaces under constant normal load (CNL) conditions were performed before and after shear tests. The surface topography was carried out using a three-dimensional (3D) laser-scanning profilometer with a parallel grid at a regular interval of 500 gin. Each surface before shearing was reconstructed by geostatistical methods according to eight different directions. A quantitative description of surfaces was performed using global and directional statistical parameters. These parameters allow to determine the surface anisotropy and to divide the .joints into three groups of similar morphology according to a given direction. Each sample of the same group is submitted to the same normal stress but to different shear rates ranging from 5 to 20 gm/s. The influences of normal stress and shear rate on the mechanical behavior of the discontinuities were investigated, as well as the influence of the sample morphology on its dilatancy behavior. The morphology data of upper and lower walls also permit to quantify the contact areas before testing. After the shear tests, sheared surfaces were scanned again and reconstructed according to the shearing direction. Based on the topography data of joint surfaces obtained before and after shearing, damage zones that occurred during shearing were located for both walls of each .joint. These characterizations of joint surfaces contribute to a better understanding of the shearing behavior of natural discontinuities. 展开更多
关键词 rock joints morphological analysis mechanical behavior experimental device ROUGHNESS
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Text Detection in Natural Scene Images Using Morphological Component Analysis and Laplacian Dictionary 被引量:7
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作者 Shuping Liu Yantuan Xian +1 位作者 Huafeng Li Zhengtao Yu 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2020年第1期214-222,共9页
Text in natural scene images usually carries abundant semantic information. However, due to variations of text and complexity of background, detecting text in scene images becomes a critical and challenging task. In t... Text in natural scene images usually carries abundant semantic information. However, due to variations of text and complexity of background, detecting text in scene images becomes a critical and challenging task. In this paper, we present a novel method to detect text from scene images. Firstly, we decompose scene images into background and text components using morphological component analysis(MCA), which will reduce the adverse effects of complex backgrounds on the detection results.In order to improve the performance of image decomposition,two discriminative dictionaries of background and text are learned from the training samples. Moreover, Laplacian sparse regularization is introduced into our proposed dictionary learning method which improves discrimination of dictionary. Based on the text dictionary and the sparse-representation coefficients of text, we can construct the text component. After that, the text in the query image can be detected by applying certain heuristic rules. The results of experiments show the effectiveness of the proposed method. 展开更多
关键词 Dictionary learning Laplacian sparse regularization morphological component analysis(MCA) sparse representation text detection
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A township-level assessment of forest fragmentation using morphological spatial pattern analysis in Qujing,Yunnan Province,China
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作者 HUANG Xiao-yuan YE Yuan-hui +4 位作者 ZHANG Zhuo-ya YE Jiang-xia GAO Jie Marc BOGONOVICH ZHANG Xing 《Journal of Mountain Science》 SCIE CSCD 2021年第12期3125-3137,共13页
Forest fragmentation is an integral part of global change.Understanding forest fragmentation patterns and dynamics are of great significance for maintaining ecosystem stability.There are great differences in the inter... Forest fragmentation is an integral part of global change.Understanding forest fragmentation patterns and dynamics are of great significance for maintaining ecosystem stability.There are great differences in the interference of natural and human factors on forests in different towns of mountainous cities,and the characteristics of forest fragmentation are also obviously different.Forest fragmentation has been broadly studied,yet,it remains poorly understood at the township-scale within mountainous cities.In this study,the spatial form of forest landscape and forest fragmentation modes of towns were examined in Qujing City,Yunnan Province,China for the years of 2006 and 2016,relying heavily on the morphological spatial pattern analysis(MSPA)and K-means clustering algorithm.Results in 2016 showed that the forest landscape morphology of Qujing could be divided into seven classes:core,perforation,islet,bridge,edge,branch and ring;with landscape areas of 41.94%,1.22%,7.04%,11.12%,23.26%,11.74%and 3.68%respectively.Compared with 2006,the changes of landscape area were 1.71%,0.02%,0.30%,1.65%,0.20%,0.19%and 0.05%respectively.The townships in Qujing varied significantly in their landscape fragmentation patterns,and these patterns were spatially dependent.Different forest landscape forms have positive spatial correlations and differences.The forest fragmentation modes of towns can be divided into four types:Low anthropogenic towns,high anthropogenic towns,complex terrain towns and gentle terrain towns.Different ways of human activities play a decisive role in forest landscape fragmentation.The expansion of construction land and agricultural land intensifies forest fragmentation;however,man-made orderly and planned ecological restoration will greatly improve the forest coverage and improve the spatial form of urban forest landscape. 展开更多
关键词 Forest fragmentation morphological spatial pattern analysis morphological type China
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Seismic data denoising under the morphological component analysis framework combined with adaptive K-SVD and wave atoms dictionary
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作者 Yangqin Guo Ke Guo Huailai Zhou 《Earthquake Research Advances》 CSCD 2021年第S01期3-7,共5页
Many different effective reflection information are often contaminated by exterior and random noise which concealed in the seismic data.Traditional single or fixed transform is not suit for exploiting their complicate... Many different effective reflection information are often contaminated by exterior and random noise which concealed in the seismic data.Traditional single or fixed transform is not suit for exploiting their complicated characteristics and attenuating the noise.Recent years,a novel method so-called morphological component analysis(MCA)is put forward to separate different geometrical components by amalgamating several irrelevance transforms.According to study the local singular and smooth linear components characteristics of seismic data,we propose a method of suppressing noise by integrating with the advantages of adaptive K-singular value decomposition(K-SVD)and wave atom dictionaries to depict the morphological features diversity of seismic signals.Numerical results indicate that our method can dramatically suppress the undesired noises,preserve the information of geologic body and geological structure and improve the signal-to-noise ratio of the data.We also demonstrate the superior performance of this approach by comparing with other novel dictionaries such as discrete cosine transform(DCT),undecimated discrete wavelet transform(UDWT),or curvelet transform,etc.This algorithm provides new ideas for data processing to advance quality and signal-to-noise ratio of seismic data. 展开更多
关键词 morphological component analysis Sparse representation K-SVD Wave atom Adaptive dictionary Seismic denoising
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Application of Decomposition and Denoising of Gearbox Signal Based on Morphological Component Analysis
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作者 邓士杰 唐力伟 +1 位作者 张晓涛 于贵波 《Journal of Donghua University(English Edition)》 EI CAS 2016年第2期239-243,共5页
Morphological component analysis( MCA) is a signal separation method based on signal morphological diversity and sparse representation. MCA can extract the signal components of different morphologies by different dict... Morphological component analysis( MCA) is a signal separation method based on signal morphological diversity and sparse representation. MCA can extract the signal components of different morphologies by different dictionary combinations. Firstly,the theory of MCA was analyzed with sparse representation principle and relaxation criterion. Then detailed steps of block coordinate relaxation( BCR) were given. Finally,algorithm performance was verified by simulation signals analysis, MCA was applied to decomposing and denoising gearbox signals, and the fault parameters were extracted by energy operator demodulation envelop of morphological component. 展开更多
关键词 morphological component analysis(MCA) sparse representation block coordinate relaxation(BCR) fault diagnosis
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Image Restoration Using Hybrid Features Improvement on Morphological Component Analysis
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作者 Der-Chang Tseng Ru-Yin Wei +1 位作者 Ching-Ta Lu Ling-Ling Wang 《Journal of Electronic Science and Technology》 CAS CSCD 2019年第4期371-381,共11页
Images are generally corrupted by impulse noise during acquisition and transmission.Noise deteriorates the quality of images.To remove corruption noise,we propose a hybrid approach to restoring a random noisecorrupted... Images are generally corrupted by impulse noise during acquisition and transmission.Noise deteriorates the quality of images.To remove corruption noise,we propose a hybrid approach to restoring a random noisecorrupted image,including a block matching 3D(BM3D)method,an adaptive non-local mean(ANLM)scheme,and the K-singular value decomposition(K-SVD)algorithm.In the proposed method,we employ the morphological component analysis(MCA)to decompose an image into the texture,structure,and edge parts.Then,the BM3D method,ANLM scheme,and K-SVD algorithm are utilized to eliminate noise in the texture,structure,and edge parts of the image,respectively.Experimental results show that the proposed approach can effectively remove interference random noise in different parts;meanwhile,the deteriorated image is able to be reconstructed well. 展开更多
关键词 Adaptive non-local mean(ANLM) block matching 3D(BM3D) image restoration morphological component analysis(MCA) singular value decomposition(SVD).
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Genetic analysis of morphological index and its related taxonomic traits for classification of indica 被引量:1
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《Chinese Rice Research Newsletter》 1999年第3期1-2,共2页
The Cheng index distinguishes indica andjaponica rice based on six taxonomic traits.This index has been widely used for classifi- cation of indica and japonica varieties in China.In this study,a double haploid(DH)popu... The Cheng index distinguishes indica andjaponica rice based on six taxonomic traits.This index has been widely used for classifi- cation of indica and japonica varieties in China.In this study,a double haploid(DH)popula-tion derived from anther culture of ZYQ8/JX17 F,a typical inter-subspecies hybrid,was used to investigate the six taxonomictraits,i.e.leaf hairiness(LH),color of hullwhen heading(CHH),hairiness of hull(HH),length of the first and second panicle internode(LPI),length/width of grain(L/W),andphenol reaction(PH).The morphological in- dex(MI)was also calculated.Based on themolecular linkage map constructed from this 展开更多
关键词 LPI MI Genetic analysis of morphological index and its related taxonomic traits for classification of indica length
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Quantitative analysis of intrusive body morphology and its relationship with skarn mineralization——A case study of Fenghuangshan copper deposit, Tongling, Anhui, China 被引量:6
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作者 Xian-cheng MAO Ying ZHAO +5 位作者 Hao DENG Bin ZHANG Zhan-kun LIU Jin CHEN Yan-hong ZOU Jian-qing LAI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第1期151-162,共12页
The shapes of intrusive body and contact zone might influence the formation and distribution of orebodies in skarn deposit.By taking Xinwuli intrusive body in Fenghuangshan copper deposit,Tongling,Anhui,China,as the r... The shapes of intrusive body and contact zone might influence the formation and distribution of orebodies in skarn deposit.By taking Xinwuli intrusive body in Fenghuangshan copper deposit,Tongling,Anhui,China,as the research object,a new method was used to obtain the quantitative relationship between intrusion morphology and skarn mineralization.The first step of the method was to extract morphological characteristic parameters based on mathematical morphology and Euclidean distance transformation;then the quantitative relationship between the parameters and orebodies was analyzed;finally correlational analyses between the parameters and mineralization indices were conducted.The results show that morphological characteristic parameters can effectively indicate the location of concealed ore bodies in skarn deposit,with the following parts as advantageous positions of skarn mineralization:(1)the parts away from the1st trend surface in the range from?25to50m;(2)the convex parts about200m away from the2nd trend surface,around which the tangent plane of the intrusive body is approximately consistent with the trend surface;(3)the contact zones with angle between intrusive body original contact surface and trend contact surface ranging from35°to70°;(4)the parts with angle between intrusive body original contact surface and regional extruding far crustal stress ranging from50°to60°.These knowledge can be applied to more skarn deposits for future mineral exploration. 展开更多
关键词 intrusive body morphological analysis contact zone mathematical morphology skarn mineralization Fenghuangshan copper deposit
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PCR-DGGE Analysis of Nematode Diversity in Cu-Contaminated Soil 被引量:4
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作者 WANG Shi-Bin LI Qi LIANG Wen-Ju JIANG Yong JIANG Si-Wei 《Pedosphere》 SCIE CAS CSCD 2008年第5期621-627,共7页
A wheat pot experiment was conducted under greenhouse conditions to assess the effect of copper contamination on soil nematode diversity by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE... A wheat pot experiment was conducted under greenhouse conditions to assess the effect of copper contamination on soil nematode diversity by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) method and morphological analysis. The soil was treated with CuSO4.5H2O at the following concentrations: 0, 50, 100, 200, 400, and 800 mg kg^-1 dry soil, and the soil samples were collected at wheat jointing and ripening stages. Nematode diversity index (H′) from morphological analysis showed no difference between the control and the treated samples in either of the sampling dates. At the wheat ripening stage, nematode diversity obtained by the PCR-DGGE method decreased noticeably in the Cu800 treatment in comparison with the control. With optimization of the method of nematode DNA extraction, PCR-DGGE could give more information on nematode genera, and the intensity of the bands could reflect the abundance of nematode genera in the assemblage. The PCR-DGGE method proved promising in distinguishing nematode diversity in heavy metal coritaminated soil. 展开更多
关键词 copper contamination morphological analysis nematode diversity PCR-DGGE
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Quantitative Analysis of Flabellophyton from the Ediacaran Lantian Biota, South China: Application of Geometric Morphometrics in Precambrian Fossil Research 被引量:1
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作者 WAN Bin YUAN Xunlai +4 位作者 CHEN Zhe GUAN Chengguo PANG Ke TANG Qing RAO Xin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第4期905-915,共11页
As a more efficient quantitative method for morphological analysis, geometric morphometrics is applied to the flabellate fossils Flabellophyton including Flabellophyton lantianensis and Flabellophyton strigata from Ne... As a more efficient quantitative method for morphological analysis, geometric morphometrics is applied to the flabellate fossils Flabellophyton including Flabellophyton lantianensis and Flabellophyton strigata from Neoproterozoic Ediacaran Lantian biota, South China. Both traditional morphometric analysis (including diverging angle, length, and width distribution) and geometric morphometric analysis [including superposition of normalized area analysis, non-metric multidimensional scaling (n-MDS), Bray-Curtis similarity cluster analysis (CLUSTER) and analysis of similarities (ANOSIM)[ were performed. The results indicate there are great interspecific morphological differences between F. lantianensis and F. strigata, in addition to some intraspecific variations within each species. Here we preliminarily suggest that the previously defined Flabellophyton should be subdivided into 2 genera at least: one marked by the dark transverse striated structure, and the other without. This recharacterization and reclassification work still needs further careful observation and comprehensive analysis with large number of flabeilate fossils combining morphology, structure, population, and community-ecology study. 展开更多
关键词 Lantian biota Flabellophyton morphological analysis geometric morphometrics
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The cause of human fatigue and scenario analysisin the process of marine transportation
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作者 Pan Hengyi 《Journal of Southeast University(English Edition)》 EI CAS 2020年第1期107-117,共11页
The framework of fatigue factors is constructed to reduce the number of maritime accidents caused by human fatigue.Based on the study of maritime human fatigue,by screening and classifying it,there are 15 fatigue fact... The framework of fatigue factors is constructed to reduce the number of maritime accidents caused by human fatigue.Based on the study of maritime human fatigue,by screening and classifying it,there are 15 fatigue factors,which can be classified into 4 types:sleep,rest and rhythm;work factors;personal conditions;environmental factors.These factors are regarded as the variables for constructing scenarios.The importance,uncertainty,influence and dependence of variables and variable pairs were assessed by using morphological analysis,quantitative scales and correlation matrices.Ship movement and workload are selected as the two key variables,which are regarded as the axes of generating scenarios.One of the scenarios is selected as the typical scenario to illustrate the relationship between the causes of fatigue.Then,the analysis framework is constructed according to the fatigue factors relationship,and several potential solutions are proposed,which include the development of foresighted and flexible work plans,and the application of wearable facilities to improve monitoring and assessment systems.The proposed framework lays a theoretical foundation for studying maritime human fatigue,and scenario analysis can provide an effective strategy for reducing crews'fatigue. 展开更多
关键词 maritime accident human fatigue fatigue factor scenario analysis scenario construction morphological analysis
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Identification of five Pampus species from the coast of China based on sagittal otolith morphology analysis 被引量:3
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作者 ZHANG Chi FAN Yannan +2 位作者 YE Zhenjiang LI Zengguang YU Hongliang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第2期51-56,共6页
Sagittal otoliths morphology were compared to identify five Pampus species of the Chinese coast(Chinese pomfret Pampus chinensis, grey pomfret P. cinereus, southern lesser pomfret P. minor, plumage pomfret P.punctati... Sagittal otoliths morphology were compared to identify five Pampus species of the Chinese coast(Chinese pomfret Pampus chinensis, grey pomfret P. cinereus, southern lesser pomfret P. minor, plumage pomfret P.punctatissmus, and Pampus sp.). Otoliths demonstrated species-specific characteristics with noticeable differences in overall shape, margin and anterior region among species. With species divergence, otoliths get thinner following further developed rostrum and anti-rostrum. Interspecies variation in otolith could associate with experienced different temperature and water column. The discriminant analysis presented a high classification accuracy of 96.6%, which confirms the inter-specific distinction of otolith shape and enable the species identification. 展开更多
关键词 otolith morphology Pampus Fourier analysis discriminant analysis
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Influence of nanosized magnesia on the hydration of borehole-sealing cements prepared using different methods 被引量:1
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作者 Quanle Zou Jinfei Zhan +1 位作者 Xin Wang Zhen Huang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第4期343-360,共18页
Gas drainage is an efective technology for gas control in coal mines.A high borehole-sealing quality is the fundamental precondition for efcient gas drainage.The expansibilities of cement pastes used in borehole-seali... Gas drainage is an efective technology for gas control in coal mines.A high borehole-sealing quality is the fundamental precondition for efcient gas drainage.The expansibilities of cement pastes used in borehole-sealing processes are critical for the borehole-sealing efect.Nanosized magnesia expansive agents are used to improve the expansibilities of cement pastes and improve the borehole-sealing efect.Nuclear magnetic resonance spectrometry and scanning electron microscopy were adopted to study the efects of nanosized magnesia on the hydration of borehole-sealing cements used with diferent preparation methods.The results showed that an increase in the mass fraction of the nanosized magnesia promoted cement hydration,and the mass fraction was positively correlated with the promotion efect.The use of diferent preparation methods did not change the water-phase distribution in the cement.When using the wet-mixing preparation method,nanosized magnesia promoted the induction,acceleration,and deceleration periods of hydration;when using the dry-mixing preparation method,the nanosized magnesia promoted the induction period of cement hydration,and the promotion efect was less obvious than that seen when using the wet-mixing method.When using the wet-mixing preparation method,the nanosized magnesia was uniformly dispersed,thus enlarging the surface area of the reaction,which provided more nucleation sites for the hydration products of the cement and therefore accelerated the hydration reaction.When using the dry-mixing preparation method,the nanosized magnesia powders were dispersed nonuniformly and aggregated.Under these conditions,only a few nanosized magnesia particles on the surfaces of the aggregated clusters took part in hydration,so only a small number of nucleation sites were provided for the hydration products of cement.This led to inconsistent hydration of cement pastes prepared using the dry-mixing method.The surface porosity of the cement prepared with the wet-mixing preparation method frst decreased and then increased with increases in the mass fraction of the nanosized magnesia.The cement surface exhibited compact hydration products and few pores,and the surface was relatively smooth.In comparison,the surface porosity of the cement prepared using the dry-mixing method fuctuated with increasing mass fraction of the nanosized magnesia,resulting in a rough cement surface and microfractures on some surfaces.The two preparation methods both reduced the surface porosity of the cement.The wet-mixing preparation was more efective and consistent in improving the compactness of the cement than the dry-mixing preparation.These results provide important guidance on the addition of nanosized magnesia in borehole-sealing engineering and the selection of cement preparation methods,and they also lay a solid foundation for realizing safe and efcient gas drainage. 展开更多
关键词 Borehole-sealing cement Nanosized magnesia Preparation method HYDRATION morphological analysis Nuclear magnetic resonance relaxation analysis
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The Impact of Microscopic Fungi on the Morphological and Structural Properties of Carbon Steel
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作者 Elena Binkauskiene Albinas Lugauskas +4 位作者 Igoris Prosycevas Vidas Pakstas Ausra Selskiene Dalia Bucinskiene Alma Rucinskiene 《Journal of Surface Engineered Materials and Advanced Technology》 2014年第4期242-248,共7页
The growth of the microscopic fungi on the solid surface has a great influence on technical materials destruction. The aim of this study was to determine the influence of two strains of micromycetesPenicillium palitan... The growth of the microscopic fungi on the solid surface has a great influence on technical materials destruction. The aim of this study was to determine the influence of two strains of micromycetesPenicillium palitansstrain6 andArthrinium phaeospermumstrain 10 on morphological and structural properties of carbon steel surfaces in the nutrient medium. The difference in consumption of chlorine byP. palitans6(0.07 wt%) andA. phaeospermum10(0.04 wt%) and the difference in accumulation of a newly formed elementmanganese forP. palitans6(0.01 wt%) andA. phaeospermum10(0.03 wt%) has been observed. A relation between the surface and interface fungal stimulated processes, the biotic oxidation of steel surface as well as formation of the mixed oxides on the biomodified steel surface has been determined. The morphology of surfaces was characterized by scanning electron microscopy, the structure—by the X-ray diffraction method, Fourier transformation infrared and X-ray fluorescence spectroscopy. 展开更多
关键词 STEEL Microscopic Fungi morphological and Structural analysis Biogenic Materials
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