针对在线文本情感摘要生成问题,本文提出了一种基于Opinosis图和马尔科夫随机游走模型的情感摘要框架.首先,该框架将原始文本转化为Opinosis图,并利用其挖掘出文本中的特征词,这些特征词可以用来对原始文本的句子进行分类;其次本文在基...针对在线文本情感摘要生成问题,本文提出了一种基于Opinosis图和马尔科夫随机游走模型的情感摘要框架.首先,该框架将原始文本转化为Opinosis图,并利用其挖掘出文本中的特征词,这些特征词可以用来对原始文本的句子进行分类;其次本文在基于聚类的条件马尔科夫随机游走模型的基础上增加了情感层,改进后的模型可以判断同一聚类中各句子的情感倾向是否具有代表性并结合情感和聚类信息对句子进行排序.实验结果表明,本文提出的方法与基准算法相比在ROUGE(Recall-Oriented Understudy for Gisting Evaluation)值上具有明显提高.展开更多
传统模糊聚类方法以像元光谱信息为基础,通过相似性准则在特征空间内进行自动聚集。高光谱图像聚类过程往往受到混合像元和“同物异谱”现象的影响,造成结果噪声和破碎严重,导致算法难以适应于高光谱图像地物识别。针对传统聚类算法的不...传统模糊聚类方法以像元光谱信息为基础,通过相似性准则在特征空间内进行自动聚集。高光谱图像聚类过程往往受到混合像元和“同物异谱”现象的影响,造成结果噪声和破碎严重,导致算法难以适应于高光谱图像地物识别。针对传统聚类算法的不足,考虑邻域像元间相关性和连续性即上下文特征,文章提出了一种新的基于空间权重自适应马尔科夫随机场模型(markov random field,MRF)的高光谱图像模糊聚类算法,在模糊C-均值聚类目标函数中引入空间项,并采用自适应权重系数控制其在聚类中的影响程度,将空间信息自适应地引入聚类过程中。通过模拟及真实高光谱数据实验证明,较仅使用光谱及分类后处理滤波算法,该算法有效提高了高光谱图像聚类的精度和抗噪能力。展开更多
在监督TS-MRF(tree-structured Markov random field)分割中,人工指定遥感影像的分层结构交互复杂且有一定的随意性。为了解决这个问题,提出一种新的基于集合划分的分层结构自动提取算法。该算法使用二叉树结构表示分层结构,并根据集合...在监督TS-MRF(tree-structured Markov random field)分割中,人工指定遥感影像的分层结构交互复杂且有一定的随意性。为了解决这个问题,提出一种新的基于集合划分的分层结构自动提取算法。该算法使用二叉树结构表示分层结构,并根据集合划分准则对遥感影像中的基本类别集合逐层划分,从而自顶向下地逐步获取分层结构。实验结果表明,该算法需要人工交互少、容易解译,且能保证监督TS-MRF影像分割的准确率和效率。展开更多
A Markov chain-based stochastic model (MCM) is developed to simulate the movement of particles in a 2D bubbling fluidized bed (BFB). The state spaces are determined by the discretized physical cells of the bed, an...A Markov chain-based stochastic model (MCM) is developed to simulate the movement of particles in a 2D bubbling fluidized bed (BFB). The state spaces are determined by the discretized physical cells of the bed, and the transition probability matrix is directly calculated by the results of a discrete element method (DEM) simulation. The Markov property of the BFB is discussed by the comparison results calculated from both static and dynamic transition probability matrices. The static matrix is calculated based on the Markov chain while the dynamic matrix is calculated based on the memory property of the particle movement. Results show that the difference in the trends of particle movement between the static and dynamic matrix calculation is very small. Besides, the particle mixing curves of the MCM and DEM have the same trend and similar numerical values, and the details show the time averaged characteristic of the MCM and also expose its shortcoming in describing the instantaneous particle dynamics in the BFB.展开更多
文摘针对在线文本情感摘要生成问题,本文提出了一种基于Opinosis图和马尔科夫随机游走模型的情感摘要框架.首先,该框架将原始文本转化为Opinosis图,并利用其挖掘出文本中的特征词,这些特征词可以用来对原始文本的句子进行分类;其次本文在基于聚类的条件马尔科夫随机游走模型的基础上增加了情感层,改进后的模型可以判断同一聚类中各句子的情感倾向是否具有代表性并结合情感和聚类信息对句子进行排序.实验结果表明,本文提出的方法与基准算法相比在ROUGE(Recall-Oriented Understudy for Gisting Evaluation)值上具有明显提高.
文摘传统模糊聚类方法以像元光谱信息为基础,通过相似性准则在特征空间内进行自动聚集。高光谱图像聚类过程往往受到混合像元和“同物异谱”现象的影响,造成结果噪声和破碎严重,导致算法难以适应于高光谱图像地物识别。针对传统聚类算法的不足,考虑邻域像元间相关性和连续性即上下文特征,文章提出了一种新的基于空间权重自适应马尔科夫随机场模型(markov random field,MRF)的高光谱图像模糊聚类算法,在模糊C-均值聚类目标函数中引入空间项,并采用自适应权重系数控制其在聚类中的影响程度,将空间信息自适应地引入聚类过程中。通过模拟及真实高光谱数据实验证明,较仅使用光谱及分类后处理滤波算法,该算法有效提高了高光谱图像聚类的精度和抗噪能力。
文摘在监督TS-MRF(tree-structured Markov random field)分割中,人工指定遥感影像的分层结构交互复杂且有一定的随意性。为了解决这个问题,提出一种新的基于集合划分的分层结构自动提取算法。该算法使用二叉树结构表示分层结构,并根据集合划分准则对遥感影像中的基本类别集合逐层划分,从而自顶向下地逐步获取分层结构。实验结果表明,该算法需要人工交互少、容易解译,且能保证监督TS-MRF影像分割的准确率和效率。
基金The National Science Foundation of China(No.51276036,51306035)the Fundamental Research Funds for the Central Universities(No.KYLX_0114)
文摘A Markov chain-based stochastic model (MCM) is developed to simulate the movement of particles in a 2D bubbling fluidized bed (BFB). The state spaces are determined by the discretized physical cells of the bed, and the transition probability matrix is directly calculated by the results of a discrete element method (DEM) simulation. The Markov property of the BFB is discussed by the comparison results calculated from both static and dynamic transition probability matrices. The static matrix is calculated based on the Markov chain while the dynamic matrix is calculated based on the memory property of the particle movement. Results show that the difference in the trends of particle movement between the static and dynamic matrix calculation is very small. Besides, the particle mixing curves of the MCM and DEM have the same trend and similar numerical values, and the details show the time averaged characteristic of the MCM and also expose its shortcoming in describing the instantaneous particle dynamics in the BFB.