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Effect of Decadal Changes in Air-Sea Interaction on the Climate Mean State over the Tropical Pacific 被引量:3
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作者 FANG Xiang-Hui ZHENG Fei 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第5期400-405,共6页
Collaboration of interannual variabilities and the climate mean state determines the type of E1 Nifio. Recent studies highlight the impact of a La Nifia-like mean state change, which acts to suppress the convection an... Collaboration of interannual variabilities and the climate mean state determines the type of E1 Nifio. Recent studies highlight the impact of a La Nifia-like mean state change, which acts to suppress the convection and low-level convergence over the central Pacific, on the predominance of central Pacific (CP) E1 Nifio in the most recent decade. However, how interannual variabilities affect the climate mean state has been less thoroughly investigated. Using a linear shallow-water model, the ef- fect of decadal changes of air-sea interaction on the two types of El Nifio and the climate mean state over the tropical Pacific is examined. It is demonstrated that the predominance of the eastem Pacific (EP) and CP E1 Nino is dominated mainly by relationships between anomalous wind stresses and sea surface temperature (SST). Furthermore, changes between air-sea interactions from 1980-98 to 1999-2011 prompted the generation of the La Ninalike pattern, which is similar to the background change in the most recent decade. 展开更多
关键词 air-sea interaction EP E1 Nifio CP E1 Nifio La Nina-like mean state change
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Calculation of Interaction Parameters from Immiscible Phase Diagram of Alkali Metal or Alkali Earth Metal-Halide System by Means of Subregular Solution Model 被引量:1
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作者 Zhaochun ZHANG, Deliang CUI, Baibiao HUANG, Xiaoyan QIN and Minhua JIANG (Institute of Crystal Materials, Shandong University, Jinan 250100, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第3期354-356,共3页
In this paper, the interaction parameters in the subregular solution model, λ1 and λ2, are regarded as a linear function of temperature, T. Therefore, the molar excess Gibbs energy of A-B binary system may be reexpr... In this paper, the interaction parameters in the subregular solution model, λ1 and λ2, are regarded as a linear function of temperature, T. Therefore, the molar excess Gibbs energy of A-B binary system may be reexpressed as follows:Gm^E=xAxB[(λ11+λ12T)+(λ21+λ22T)xB]The calculation of the model parameters, λ11, λ12, λ21and λ22, was carried out numerically from the phase diagrams for 11 alkali metal-alkali halide or alkali earth metal-halide systems. In addition, artificial neural network trained by known data has been used to predict the values of these model parameters. The predicted results are in good agreement with the .calculated ones. The applicability of the subregular solution model to the alkali metal-alkali halide or alkali earth metal-halide systems were tested by comparing the available experimental composition along the boundary of miscibility gap with the calculated ones which were obtained by using genetic algorithm. The good agreement between the calculated and experimental results across the entire liquidus is valid evidence in support of the model. 展开更多
关键词 In Calculation of interaction Parameters from Immiscible Phase Diagram of Alkali Metal or Alkali Earth Metal-Halide System by means of Subregular Solution Model
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Generalized Mean-Flow Theory of Wave-Current-BottomInteractions 被引量:1
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作者 黄虎 《China Ocean Engineering》 SCIE EI 2006年第1期165-172,共8页
The interaction between waves, currents and bottoms in estuarine and coastal regions is ubiquitious, in particular the dynamic mechanism of waves on large-scale slowly varying currents. The wave action concept may be ... The interaction between waves, currents and bottoms in estuarine and coastal regions is ubiquitious, in particular the dynamic mechanism of waves on large-scale slowly varying currents. The wave action concept may be extended and applicated to the study of the mechanism. Considering the effects of moving bottoms and starting from the Navier-Stokes equation of motion of a vinous fluid including the Coriolis force, a generalized mean-flow medel theory for the nearshore region, that is, a set of mean-flow equations and their generalized wave action equation involving the three new kinds of actions termed respectively as the current wave action, the bottom wave action and the dissipative wave action which can be applied to arbitrary depth over moving bottoms and ambient currents with a typical vertical structure, is developed by vertical integration and time-averaglng over a wave peried, thus extending the classical concept, wave action, from the ideal averaged flow conservative system to the real averaged flow dissipative dynamical system, and having a large range of application. 展开更多
关键词 mean-flow equations wave action large-scale slowly varying currents wave-current-bottom interactions dissipative dynamical system
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RELATIONSHIPS BETWEEN DIFFERENT TROPICAL CONVECTIVE ACTIVITIES AND LOW FREQUENCY WAVE-MEAN FLOW INTERACTIONS
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作者 余斌 黄荣辉 《Journal of Tropical Meteorology》 SCIE 1995年第1期46-55,共10页
Based on ECMWF objective analysis data, and with use of Batterworth bandpass-filtered skill and diagnostic analysis method, the interaction characteristics of low frequency wave and mean flow in midlatitudes during t... Based on ECMWF objective analysis data, and with use of Batterworth bandpass-filtered skill and diagnostic analysis method, the interaction characteristics of low frequency wave and mean flow in midlatitudes during the winter years of 1983 / 1984 and 1986 / 1987 have been studied in this paper. The main results point out the important role of the tropical convective activity on the above mentioned interaction process. 展开更多
关键词 TROPICAL convection ACTIVITIES LOW-FREQUENCY FLUCTUATION wave-mean FLOW interaction
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MEAN-FIELD LIMIT OF BOSE-EINSTEIN CONDENSATES WITH ATTRACTIVE INTERACTIONS IN R^2
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作者 郭玉劲 陆璐 《Acta Mathematica Scientia》 SCIE CSCD 2016年第2期317-324,共8页
Starting with the many-body SchrSdinger Hamiltonian in R2, we prove that the ground state energy of a two-dimensional interacting Bose gas with the pairwise attractive interaction approaches to the minimum of the Gros... Starting with the many-body SchrSdinger Hamiltonian in R2, we prove that the ground state energy of a two-dimensional interacting Bose gas with the pairwise attractive interaction approaches to the minimum of the Gross-Pitaevskii energy functional in the mean- field regime, as the particle number N → ∞ and however the scattering length → 0. By fixing N|k|, this leads to the mean-field approximation of Bose-Einstein condensates with attractive interactions in R^2. 展开更多
关键词 Bose-Einstein condensation attractive interactions Gross-Pitaevskii func-tional mean-field approximation
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Interaction of diabatic processes, large-scale eddies and the mean atmospheric circulation over the Atlantic, Arctic and Eurasia
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作者 Ralf JAISER D?rthe HANDORF Klaus DETHLOFF 《Advances in Polar Science》 CSCD 2019年第2期81-92,共12页
In the last decade, the atmospheric part of the climate system experienced a shift from pronounced zonal to stronger meridional flow configurations and regionally diverse changes and trends. The climate system shows c... In the last decade, the atmospheric part of the climate system experienced a shift from pronounced zonal to stronger meridional flow configurations and regionally diverse changes and trends. The climate system shows complex interactions and nonlinear behavior, manifested in global warming, rising ocean temperatures and the retreat of Arctic sea ice. Although atmospheric trends and changes are observed, underlying processes are not well understood. In this study we diagnose the interaction of large-scale atmospheric eddies and the mean flow with respect to diabatic heating and cooling processes that impact on the atmospheric advection of heat. For this purpose, three-dimensional Eliassen-Palm flux theory is used in combination with an analysis of the thermodynamic equation, diabatic heating and cooling and heat advection. The most recent decades of observed winter climate are evaluated in terms of climatology and trends over the Atlantic, Arctic and Eurasia. The change of the atmospheric circulation and related processes differ between early and late winter. In early winter, the interaction of macro-turbulent eddies with the mean flow is inhibited at the Atlantic jet stream entrance region and atmospheric heat is meridionally advected into the Arctic, both related to strong high pressure anomalies. In late winter, these anomalies are inverted and a negative phase of the Arctic Oscillation with a more wavy mean flow and a tendency towards stronger meridionalization is observed. 展开更多
关键词 diabatic heating heat advection wave-mean flow interactions North ATLANTIC OSCILLATION ARCTIC OSCILLATION sea ice climate change ARCTIC Amplification polar-mid-latitude linkages
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Influences of Task Type on Interaction under Group Work Setting
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作者 刘晓萍 《山东师范大学外国语学院学报(基础英语教育)》 2005年第5期36-40,共5页
Interaction between learners under group work setting is considered to be significantly influenced by task types. The present empirical study was designed to explore interaction characteristics under convergent tasks ... Interaction between learners under group work setting is considered to be significantly influenced by task types. The present empirical study was designed to explore interaction characteristics under convergent tasks and divergent tasks from three aspects: language production, meaning negotiation and attention to form while performing different types of tasks. The results reveal that there was significant statistical difference in the total language production between two types of tasks. In terms of the occurrence of meaning negotiation and the extent to which students paid attention to language form, there were no significant difference between the two task types. 展开更多
关键词 中小学 英语教学 小组合作学习 任务型教学 教学内容 教学方法
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Comparative simulation study of effects of eddy-topography interaction in the East/Japan Sea deep circulation
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作者 CHOI Youngjin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第7期1-18,共18页
In this study the structure and seasonal variations of deep mean circulation in the East/lapan Sea (E/S) were numerically simulated using a mid-resolution ocean general circulation model with two different parameter... In this study the structure and seasonal variations of deep mean circulation in the East/lapan Sea (E/S) were numerically simulated using a mid-resolution ocean general circulation model with two different parameterizations for the eddy-topography interaction (ETI). The strong deep mean circulations observed in the EIS are well reproduced when using the ETI parameterizations. The seasonal variability in the EIS deep layer is shown by using ETI parameterization based on the potential vorticity approach, while it is not shown in the statistical dynamical parameterization. The driving mechanism of the strong deep mean currents in the E/S are discussed by investigating the effects of model grids and parameterizations. The deep mean circulation is more closely related to the baroclinic process and potential vorticity than it is to the wind driven circulation. 展开更多
关键词 East/Iapan Sea deep mean current seasonal variability ocean general circulation model eddy- topography interaction
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Influence of Hyperon-Hyperon Interaction on Properties of Hadronic Star
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作者 米爱军 尤伟 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第1期133-137,共5页
The influences of hyperon-hyperon interaction on the overall properties of hadronic star are investigated in the framework of relativistic mean field (RMF) theory. For certain hyperon coupling, the weaker hyperon-hy... The influences of hyperon-hyperon interaction on the overall properties of hadronic star are investigated in the framework of relativistic mean field (RMF) theory. For certain hyperon coupling, the weaker hyperon-hyperon interaction can lead to the heavier hadronic star, which accords with the observation of heavy neutron star in X-ray binaries. We find that the threshold densities of the hyperons with larger masses are brought to a lower values with the increase of the hyperon-hyperon interaction. The possibility of the existence of hyperon star is checked with the consideration of hyperon-hyperon interaction. 展开更多
关键词 hyperon interaction relativistic mean field theory hadronic star
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Affective Meaning of Pronouns in a Russian Sample
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作者 Leonid Dorfman 《Journal of Literature and Art Studies》 2016年第9期1042-1055,共14页
The present study examines affective meaning of pronouns (in Russian) represented by the semantic differential. Of direct relevance to the present study is the theory of affective meaning propounded by Osgood. Two h... The present study examines affective meaning of pronouns (in Russian) represented by the semantic differential. Of direct relevance to the present study is the theory of affective meaning propounded by Osgood. Two hypotheses were tested. According to a "magnitude" hypothesis, affective dimensions (each of evaluation, potency, and activity taken separately) differ in their magnitude across pronouns I, My, Me, and They. A "structural" hypothesis stated that the affective dimensions yield latent factors across (the generality) and within (the concept-scale interaction) the pronoun concepts. Repeated-measures analysis of variance (1-way ANOVA) and confirmatory factor analysis were employed to process data. It was found that each of the evaluation and potency measures yield a significant magnitude change across the pronouns, but there was indicated no significant change across the pronouns with respect to the activity dimension. Therewith, the pronoun My gained a salient value and the pronoun They the smallest value. Using confirmatory factor analysis five models were tested. Among them one model was good fit to the data. It engaged a four-factor solution resulted in that four pronouns are latent affective distinct but related factors and the evaluation, potency, and activity are their indicators. 展开更多
关键词 personal pronouns affective meaning semantic differential GENERALITY concept-scale interaction
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Means of Choice for Interactive Management of Dynamic Geometry Problems Based on Instrumented Behaviour
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作者 Philippe R. Richard Michel Gagnon +2 位作者 Josep Maria Fortuny Nicolas Leduc Michèle Tessier-Baillargeon 《American Journal of Computational Mathematics》 2013年第3期41-51,共11页
Our paper presents a project that involves two research questions: does the choice of a related problem by the tutorial system allow the problem solving process which is blocked for the student to be restarted? What i... Our paper presents a project that involves two research questions: does the choice of a related problem by the tutorial system allow the problem solving process which is blocked for the student to be restarted? What information about learning do related problems returned by the system provide us? We answer the first question according to the didactic engineering, whose mode of validation is internal and based on the confrontation between an a priori analysis and an a posteriori analysis that relies on data from experiments in schools. We consider the student as a subject whose adaptation processes are conditioned by the problem and the possible interactions with the computer environment, and also by his knowledge, usually implicit, of the institutional norms that condition his relationship with geometry. Choosing a set of good problems within the system is therefore an essential element of the learning model. Since the source of a problem depends on the student’s actions with the computer tool, it is necessary to wait and see what are the related to problems that are returned to him before being able to identify patterns and assess the learning. With the simultaneity of collecting and analysing interactions in each class, we answer the second question according to a grounded theory analysis. By approaching the problems posed by the system and the designs in play at learning blockages, our analysis links the characteristics of problems to the design components in order to theorize on the decisional, epistemological, representational, didactic and instrumental aspects of the subject-milieu system in interaction. 展开更多
关键词 DIDACTICS of Mathematics Competencies Geometric Thinking TUTORIAL System Related PROBLEMS Dynamic Geometry Instrumented Behavior Cognitive interactions CONCEPTIONS Mathematical Work Space meanS of CHOICE Didactic Contract
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An Empirical Study on Interaction in EFL Classrooms in Middle Schools in Western Areas of China
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作者 WEI Jing JIANG Yu-hong 《Sino-US English Teaching》 2013年第9期665-675,共11页
Interaction in EFL (English as a foreign language) classrooms has received much attention in recent years However, little research exists that has investigated interaction in Chinese EFL classrooms. To bridge this g... Interaction in EFL (English as a foreign language) classrooms has received much attention in recent years However, little research exists that has investigated interaction in Chinese EFL classrooms. To bridge this gap, the current research investigates interaction in EFL classrooms in middle schools in China in terms of: (1) the amount of teacher talk and interaction; (2) the type of teacher questions and teacher feedbacks; and (3) the amount and forms of meaning negotiation. The data set include observation records and observation reports of 140 naturally occurring lessons in middle schools in China. The findings reveal that there is not much interaction in EFL lessons in middle schools in western areas of China, which is shown by class time dominated by TTT (teacher talking time), teacher questions and feedbacks that do not encourage students' responses and very little negotiation of meaning Possible causes are analyzed, and implications of this research for EFL teaching in China, teacher development and further research are also discussed 展开更多
关键词 teacher-student(s) interaction student(s)-student(s) interaction teacher questions teacher feedback negotiation of meaning
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A Brief Analysis of Meaning Negotiation between Teachers and Students
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作者 窦金瞳 《海外英语》 2019年第23期259-260,264,共3页
Meaning negotiation builds the connection that speakers communicate and cooperate.It is also the interaction to solve dif⁃ficulties in comprehension.By researching the problems of English classroom teaching,this paper... Meaning negotiation builds the connection that speakers communicate and cooperate.It is also the interaction to solve dif⁃ficulties in comprehension.By researching the problems of English classroom teaching,this paper finds the necessity and the ad⁃vantages of meaning negotiation between teachers and students that is compared with traditional classroom teaching.It makes sug⁃gestions on how teachers take teaching activities and introductory ways to make meaning negotiation work. 展开更多
关键词 meaning negotiation classroom interaction and comprehensible output
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一种尺度自适应的Mean Shift跟踪算法 被引量:15
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作者 张凤军 赵岭 +2 位作者 安国成 王宏安 戴国忠 《计算机研究与发展》 EI CSCD 北大核心 2014年第1期215-224,共10页
针对传统Mean Shift中跟踪窗口尺度不能实时适应跟踪目标变化这一问题,提出一种基于图割理论的Mean Shift尺度自适应算法.根据每一帧图像的Mean Shift迭代结果,在其周围的一个小区域内,利用先验的肤色混合高斯模型构造图并建立关于标号... 针对传统Mean Shift中跟踪窗口尺度不能实时适应跟踪目标变化这一问题,提出一种基于图割理论的Mean Shift尺度自适应算法.根据每一帧图像的Mean Shift迭代结果,在其周围的一个小区域内,利用先验的肤色混合高斯模型构造图并建立关于标号的能量模型,使用max flow/min cut算法计算出能量函数最小值实现图割,在图割后的肤色团块中寻找最大团判定为跟踪目标,并以该团的尺度来实时调整目标跟踪窗口.实验结果表明,该方法克服了缩放10%核带宽的经典尺度适应方法的带宽趋于缩小问题,实时地反映跟踪目标真实尺度变化,避免背景中其他目标的干扰,具有较好的实用性和鲁棒性,而且可以应用到娱乐游戏控制中,丰富人机交互操作方式. 展开更多
关键词 图割理论 均值移动 尺度自适应 跟踪 人机交互
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基于K-means聚类与决策树的有线电视交互服务订制预测
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作者 杨怀珍 李玲华 《微型机与应用》 2009年第24期67-70,共4页
建立了一种基于聚类分析与决策树分析相结合的服务订制预测模型,阐述了聚类分析Kmeans算法、决策树算法C5.0算法原理、建模流程的设计,将模型应用于某地区用户对有线电视交互服务的订制意愿预测,最终确定高响应率客户群。实验证明,该模... 建立了一种基于聚类分析与决策树分析相结合的服务订制预测模型,阐述了聚类分析Kmeans算法、决策树算法C5.0算法原理、建模流程的设计,将模型应用于某地区用户对有线电视交互服务的订制意愿预测,最终确定高响应率客户群。实验证明,该模型相对于仅通过决策树进行预测能更大程度地提高分类精度,并能更有效地识别出高响应率客户群。 展开更多
关键词 K-meanS聚类 决策树 C5.0 有线电视交互服务
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基于Mean Shift和随机游走的图像分割算法
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作者 穆克 程伟 禇俊霞 《辽宁工业大学学报(自然科学版)》 2012年第1期27-30,共4页
提出了一种改进的随机游走算法。首先,采用Mean Shift算法对图像进行预处理,将图像划分成一些同质区域,用同质区域作为节点进行随机游走,在降低节点数的同时也抑制了噪声对分割的影响;其次,利用马氏距离定义区域之间的权值;对种子点进... 提出了一种改进的随机游走算法。首先,采用Mean Shift算法对图像进行预处理,将图像划分成一些同质区域,用同质区域作为节点进行随机游走,在降低节点数的同时也抑制了噪声对分割的影响;其次,利用马氏距离定义区域之间的权值;对种子点进行了改进,增加了辅助种子点,利用辅助种子点和用户标记的种子点进行随机游走,实现同质区域的合并,实现图像的最终分割。实验结果表明,该算法提高了图像分割的精度。 展开更多
关键词 交互式图像分割 meanSHIFT算法 随机游走算法
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基于Mean-shift聚类的交互式图像分割
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作者 李丽君 《科学技术与工程》 2011年第25期6095-6097,共3页
提出了一种基于Mean-shift聚类的交互式图像分割算法。首先利用Mean-shift聚类算法初步分割图像,然后用户只需简单地输入交互信息,大致标识出部分对象点和背景点,再根据区域间的最大相似性准则合并区域,分割出感兴趣区域。实验表明,此... 提出了一种基于Mean-shift聚类的交互式图像分割算法。首先利用Mean-shift聚类算法初步分割图像,然后用户只需简单地输入交互信息,大致标识出部分对象点和背景点,再根据区域间的最大相似性准则合并区域,分割出感兴趣区域。实验表明,此算法简单有效,能准确地从复杂背景中提取对象轮廓。 展开更多
关键词 mean—shift聚类 交互式分割 区域合并
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基于K-Means ++聚类的体绘制高维传递函数设计方法 被引量:7
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作者 岑梓源 李彬 田联房 《计算机应用》 CSCD 北大核心 2012年第12期3404-3407,共4页
如何将体数据中重要的信息高质量地绘制出来是医学可视化急需解决的问题。基于高维直方图的高维传递函数交互设计法是目前流行的方法,但是该方法设计复杂且效果不理想。针对高维特征的传递函数设计问题,提出一个基于改进的K均值(K-Means... 如何将体数据中重要的信息高质量地绘制出来是医学可视化急需解决的问题。基于高维直方图的高维传递函数交互设计法是目前流行的方法,但是该方法设计复杂且效果不理想。针对高维特征的传递函数设计问题,提出一个基于改进的K均值(K-Means++)聚类的高维传递函数自动设计与交互式的体绘制方法:首先,对三维数据场进行特征提取;然后,采用基于K-Means++聚类的传递函数自动生成方法;最后,提供便捷的交互式界面给用户进行调整。还利用基于图形处理器(GPU)的体绘制方法,充分利用图形卡的强大并行计算能力,达到实时绘制的效果。实验结果表明,该方法能消除高维传递函数设计的复杂性,并且能有效地融合多种人体组织结构特征,提高渲染效果。 展开更多
关键词 体绘制 K-means++ 传递函数 人机交互
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基于改进k-means算法的电网数据实时交换方法研究 被引量:9
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作者 陈静鹏 王子强 +1 位作者 李家璐 张勇 《电子设计工程》 2020年第5期162-166,共5页
针对传统k-means算法对电网数据实时交换过程控制效果不佳,交互过程不稳定,交互时间长等问题,对k-means算法进行改选,提出了一种新的电网数据实时交换方法。以电压数据、功率数据、电流数据及容量数据为基础数据建立电网数据实时交换数... 针对传统k-means算法对电网数据实时交换过程控制效果不佳,交互过程不稳定,交互时间长等问题,对k-means算法进行改选,提出了一种新的电网数据实时交换方法。以电压数据、功率数据、电流数据及容量数据为基础数据建立电网数据实时交换数学模型;由发电机、输电线路、配电线路和低压线路构建电网结构,通过电网数据预处理、特征数据提取、k-means计算实现电网数据的实时交互。为检测方法效果,与传统k-means算法进行对比,设计了对比实验。结果表明,给出的方法在电网数据交互过程中稳定性高,交互时间短,能够为用户提供质量更高的电能。 展开更多
关键词 改进K-meanS算法 电网数据 实时交互 数据交互
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基于K-means和图割的脑部MRI分割算法 被引量:2
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作者 田换 覃晓 +2 位作者 元昌安 刘致锦 廖剑平 《数据采集与处理》 CSCD 北大核心 2016年第5期974-982,共9页
为了克服原始图割算法在用户选定的像素种子点较少情况下,目标边界容易出现错分这一现象,本文提出了基于K-means和图割(Graph cut,GC)算法相结合的交互式K-均值图割(K-means and graph cut,KMGC)算法,对脑部核磁共振图像(Magnetic reson... 为了克服原始图割算法在用户选定的像素种子点较少情况下,目标边界容易出现错分这一现象,本文提出了基于K-means和图割(Graph cut,GC)算法相结合的交互式K-均值图割(K-means and graph cut,KMGC)算法,对脑部核磁共振图像(Magnetic resonance image,MRI)进行交互式操作,该算法通过K-means聚类,对脑部MRI的灰度不均匀性进行了处理,在此基础上,再使用图割算法进一步对脑部MRI进行细化,从而达到有效地分割脑白质和脑灰质的目的。本文分别在仿真和真实的脑部MRI数据上进行了大量的实验,分别从定量分析和定性分析两个角度对实验结果进行了分析,并与其他分割算法进行了对比,对比实验结果标明,KMGC算法能够有效地对脑部MRI进行分割,并在分割效果上优于其他算法。 展开更多
关键词 图割 交互式 核磁共振图像 K-均值
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