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Surface reconstruction of complex contour lines based on chain code matching technique 被引量:1
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作者 姜晓彤 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期432-435,共4页
A new method for solving the tiling problem of surface reconstruction is proposed. The proposed method uses a snake algorithm to segment the original images, the contours are then transformed into strings by Freeman'... A new method for solving the tiling problem of surface reconstruction is proposed. The proposed method uses a snake algorithm to segment the original images, the contours are then transformed into strings by Freeman' s code. Symbolic string matching technique is applied to establish a correspondence between the two consecutive contours. The surface is composed of the pieces reconstructed from the correspondence points. Experimental results show that the proposed method exhibits a good behavior for the quality of surface reconstruction and its time complexity is proportional to mn where m and n are the numbers of vertices of the two consecutive slices, respectively. 展开更多
关键词 chain code string matching surface reconstruction local shape feature
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葡萄脊虎天牛的初步研究
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作者 王引 王天书 《生产率系统》 1998年第2期64-65,共2页
葡萄脊虎天牛,又名葡萄虎天牛,在我省1年1代,以中幼龄幼早越冬,以幼虫蛀食主,侧蔓,导致蔓枯死,严重影响产量和庭园观赏价值,上于钻蛀危害,难以防治,所以是葡萄的重要害虫之一。
关键词 葡萄脊虎天牛 葡萄 生活习性 表态特征 生活史
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Morphological Studies on the Infraciliature of a Planktonic Ciliate,Tintinnopsis brasiliensis(Ciliophora:Tintinina) 被引量:1
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作者 CAI Shengfang SONG Weibo +1 位作者 XU Dapeng CHIANG Kuoping 《Journal of Ocean University of China》 SCIE CAS 2006年第1期55-57,共3页
A poorly-described marine planktonic ciliate, Tintinnopsis brasiliensis Kofoid & Campbell, 1929, collected from the Taiping Cape of Qingdao, China, was morphologically investigated based on permanent preparation afte... A poorly-described marine planktonic ciliate, Tintinnopsis brasiliensis Kofoid & Campbell, 1929, collected from the Taiping Cape of Qingdao, China, was morphologically investigated based on permanent preparation after protargol impregnation and was compared with other related congeners. According to the infraciliature, three ciliary groups can be recognized, which reveals a very stable structure among specimens and denotes that the pattern of infraciliature is, apart from the features of the lorica, a highly reliable criterion for species identification. 展开更多
关键词 INFRACILIATURE Tintinnina CILIOPHORA Tintinnopsis brasiliensis
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Solving Laguerre-Gauss Mode Eigenvectors and Eigenfunctions in Entangled State Representation
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作者 FAN Hong-Yi GAO Wei-Bo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第4期617-620,共4页
We solve the Laguerre-Gauss mode eigenvectors and eigenfunctions in the entangled state representation by searching for common eigenvectors of the 2-dimensional harmonic oscillator's total energy operator and the ang... We solve the Laguerre-Gauss mode eigenvectors and eigenfunctions in the entangled state representation by searching for common eigenvectors of the 2-dimensional harmonic oscillator's total energy operator and the angular momentum operator, We find that in the entangled state representation the eigen-solution satisfies the Hukuhara equation, and its solution is confluent hypergeometric function. 展开更多
关键词 Laguerre-Gauss modes entangled state representation
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Wear Debris Identification Using Feature Extraction and Neural Network
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作者 王伟华 马艳艳 +1 位作者 殷勇辉 王成焘 《Journal of Donghua University(English Edition)》 EI CAS 2004年第4期42-45,共4页
A method and results of identification of wear debris using their morphological features are presented. The color images of wear debris were used as initial data. Each particle was characterized by a set of numerical ... A method and results of identification of wear debris using their morphological features are presented. The color images of wear debris were used as initial data. Each particle was characterized by a set of numerical parameters combined by its shape, color and surface texture features through a computer vision system. Those features were used as input vector of artificial neural network for wear debris identification. A radius basis function (RBF) network based model suitable for wear debris recognition was established, and its algorithm was presented in detail. Compared with traditional recognition methods, the RBF network model is faster in convergence, and higher in accuracy. 展开更多
关键词 wear debris CHARACTERIZATION neural network pattern recognition.
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A Preliminary Study on Breeding of Ideal Plant in Millet 被引量:6
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作者 闫宏山 《Agricultural Science & Technology》 CAS 2009年第4期154-158,共5页
To further increase millet yield, the ideal plant in millet has become the goal of high yield breeding for millet. Taking crossbreeding or dynamic breeding technique as dominant and technologies such as modern selecti... To further increase millet yield, the ideal plant in millet has become the goal of high yield breeding for millet. Taking crossbreeding or dynamic breeding technique as dominant and technologies such as modern selection or system selection as subsidiary, progenies with ideal plant are selected by using new germplasms such as Lilvgu and Lizigu with the significant difference in plant type to other cultivars as parents. The ge- netic characteristics of new germplasms in breeding are also emphatically analyzed to summarize the breeding experience of ideal plant, which has been proved that the combination of ideal plant and heterosis utilization is one of the important ways to raise millet yield breakthrough. 展开更多
关键词 MILLET Ideal plant BREEDING
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A New Kind of Bipartite Entangled State Representation and its Application
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作者 XU Shi-Min XU Xing-Lei +1 位作者 LI Hong-Qi WANG Ji-Suo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第2期209-214,共6页
We construct four linear composite operators for a two-particle system and give common eigenvectors of those operators. The technique of integration within an ordered product of operators is employed to prove that tho... We construct four linear composite operators for a two-particle system and give common eigenvectors of those operators. The technique of integration within an ordered product of operators is employed to prove that those common eigenvectors are complete and orthonormal. Therefore, a new intermediate coordinate-momentum representation for a two-particle system is proposed and applied to some two-body dynamic problems. 展开更多
关键词 two-particle system intermediate coordinate-momentum representation IWOP technique
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Morphological Characteristics and Environmental Implications of Phytoliths in Topsoils from Different Vegetation Zones on Northern Slope of Changbai Mountains,China
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作者 QIAO Zhihe JIE Dongmei +2 位作者 LIU Hongmei GE Yong ZHANG Hongyan 《Chinese Geographical Science》 SCIE CSCD 2010年第6期506-512,共7页
The Changbai Mountains,located in the temperate monsoon climate zone of East Asia,is an ideal loca-tion for the research on timberline response to global changes.In this study,the topsoils were collected from differen... The Changbai Mountains,located in the temperate monsoon climate zone of East Asia,is an ideal loca-tion for the research on timberline response to global changes.In this study,the topsoils were collected from different vertical vegetation zones on the northern slope of the Changbai Mountains,Northeast China in August 2009,and phytoliths in the soil samples were extracted by using wet oxidation method and identified with Motic 2.0 microscope in laboratory.The results show that phytoliths are abundant in the topsoils of the study area.The herbal phytoliths are primarily composed of elongated,tooth-shaped,point-shaped and hat-shaped phytoliths,as well as a small amount of fan-shaped and square-shaped ones.The elongated,tooth-shaped,point-shaped and hat-shaped phytoliths are representative of cold climate,while fan-shaped and square-shaped ones are representative of warm and humid climate.In the conifer broadleaved mixed forest zone,coniferous forest zone and broadleaf forest zone,there are close correlations between vegetation and woody phytoliths in the topsoils,indicating that the woody plants of a region can be reconstructed from the woody phytolith assemblages in the topsoils.Meanwhile,the topsoil phytolith assemblages can also be used to reconstruct the understory herbs effectively.The phytolith assemblages in the topsoils of the forest community and herbal community differ significantly,which can help indicate the historical location of the timberline. 展开更多
关键词 topsoil phytolith TIMBERLINE environmental implication vertical vegetation zones Changbai Mountains
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Super-harmonic resonance characteristic of a rigid-rotor ball bearing system caused by a single local defect in outer raceway 被引量:2
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作者 YANG Rui JIN YuLin +1 位作者 HOU Lei CHEN YuShu 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2018年第8期1184-1196,共13页
The studies on dynamics of a fault bearing system are prevalent in recent years, however, we are studying a completely different frequency range than the one where the bearing faults are best seen. Considering a local... The studies on dynamics of a fault bearing system are prevalent in recent years, however, we are studying a completely different frequency range than the one where the bearing faults are best seen. Considering a local defect on outer raceway,a two-degree-of-freedom analytical model of a rigid-rotor ball bearing system is established. Three pulse force models are introduced to simulate the local defect. The frequency domain method—harmonic balance method with alternating frequency/time domain technique (HB-AFT) is used to calculate the response in a large frequency range. By comparing the performance at different frequencies, the fault systems with different defect models and parameters reveal the super-harmonic resonances,and the reasons for this phenomenon are uncovered as well. Finally, the theoretical calculation is verified qualitatively by the experimental results, through comparing the frequency spectrums of the defective bearing rotor system to the fault-free one.Therefore, the super-harmonic resonances can be regarded as a dynamic feature. Besides, the obvious super-harmonic resonances indicate the magnification of the harmonics of the "characteristic defect frequency" for outer race in the corresponding speed regions, which may be helpful for the diagnosis of a rotor ball bearing system with a local defect. 展开更多
关键词 rotor bearing system local defect super-harmonic resonance HB-AFT method
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A new approach to the time evolution of characteristic function of the density operator obtained by virtue of thermal entangled state representation 被引量:3
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作者 CHEN Feng FAN HongYi 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第11期2076-2080,共5页
Like the progress made by Dirac that wave function ψ(x) was reformed as x |ψ,where x| is the coordinate representation,we endow the characteristic function χλ = Tr(e λa-λaρ) of density operator ρ with the mean... Like the progress made by Dirac that wave function ψ(x) was reformed as x |ψ,where x| is the coordinate representation,we endow the characteristic function χλ = Tr(e λa-λaρ) of density operator ρ with the meaning of wave function of |ρ in the thermal entangled state η| representation in the doubled Fock space,χλ = η = λ|ρ,where |ρ = ρ|η = 0.We find the time evolution of χλ can then be directly and neatly obtained via this approach.The way of deriving the density operator from η = λ | ρ is also presented. 展开更多
关键词 characteristic function density operator master equations thermal entangled state representation
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Interpretation of English Ambiguous VerbLocative Prepositional Phrase Constructions by Mandarin and Spanish Speakers:Evidence for the Representational Deficit Hypothesis
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作者 胡阳 《Chinese Journal of Applied Linguistics》 2014年第3期334-357,F0003,共25页
This paper presents an empirical study of the acquisition of English ambiguous verb-locative prepositional phrase constructions (VLPPs) by adult Mandarin and Spanish speakers. This study assumes that the semantic pr... This paper presents an empirical study of the acquisition of English ambiguous verb-locative prepositional phrase constructions (VLPPs) by adult Mandarin and Spanish speakers. This study assumes that the semantic properties of the target VLPPs that relate to change-of-location in sentences such as The boat floated under the bridge arise from an uninterpretable syntactic feature selected by English but unselected by Mandarin Chinese and Spanish. Results obtained from an animated cartoon selection task indicate that neither the Mandarin nor the Spanish speakers at any level of English proficiency possess native-like interpretative knowledge. Tense/ Aspect effects on the interpretation of the target constructions by Spanish speakers were also found. These results are interpreted as consistent with the Representational Deficit Hypothesis view (Hawkins, 2003, 2005) of adult second language acquisition. 展开更多
关键词 English ambiguous VLPPs L1 Mandarin Chinese L1 Spanish uninterpretable features in adult L2 acquisition Tense/Aspect representational deficit hypothesis
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