一种基于本体的文本聚类方法

基于本体的文本聚类方法,在文本表示上引入WordNet,并定义了关键概念集,使用WordNet中的概念节点及概念间的语义关系减少文本特征向量维数,提高聚类效果.聚类过程中,算法使用文本的关键概念集和概念特征向量计算文本相似度,利用文本的关键概念集标注聚簇为聚类结果中的各个簇提供解释.实验结果表明,该方法有效地减少了文本特征向量的维数,提高了文本聚类效果以及聚类结果的可解释性.     

基于SS/OSF实现高维稀疏数据对象的聚类

为了解决传统聚类方法处理高维稀疏数据对象时聚类结果不理想的问题,提出了SS/OSF聚类方法.该方法基于对象组相似度(SS)和对象组特征向量(OSF),并借助对象组特征向量的可加性实现. 采用本方法得到高维稀疏数据对象的聚类结果后,可以根据聚类结果中各个对象集合的上确界和下确界为新对象进行对象组分类. 实验表明,与传统K-means聚类方法相比,随着数据对象数目的增加,该方法无论是在运行时间上,还是在聚类结果的准确度方面都有明显的改进.     

概率假设密度滤波的谱聚类目标状态提取方法

提出了一种谱聚类目标状态提取方法来实现概率假设密度(PHD)滤波中序贯蒙特卡罗(SMC)实现方式的多目标状态估计.该方法利用PHD滤波SMC实现方式输出的大量的加权粒子点间的相似度关系建立相似矩阵,通过变换得到拉普拉斯矩阵,进而对拉普拉斯矩阵进行特征分解,以实现粒子点的聚类,再在每类中寻找粒子的聚类点作为多目标状态的估计值,同时为了减小计算量,利用Nystrm逼近方法求解特征向量.仿真实验表明,PHD滤波的谱聚类目标状态提取方法的估计精度比k均值目标状态提取方法提高了60%以上.     

聚类方法在警报数据分类与约简中的应用

提出了一个使用文本聚类方法进行警报数据分类与约简的处理框架.详细描述了警报特征向量的表示方法和直接聚类方法,以及警报数据的简约表示方法.     

基于动态加权模糊核聚类算法的医学图像分割新方法

采用动态加权的模糊核聚类算法对CT医学图像进行分割.该算法对模糊核聚类算法中的特征向量进行动态加权,以自动削弱噪声特征向量在聚类中的作用,这样可以减小噪声对图像分割的干扰.实验结果表明,采用该种新算法对CT图像分割后,可以获得更清晰的分割图像.     

基于二分K均值聚类和最近特征线的视频超分辨率重建方法

提出一种基于二分K均值聚类和最近特征线的视频超分辨率重建方法.该方法在生成图像块训练样本库阶段,为了解决传统K均值算法对图像块聚类时间复杂度较大的问题,设计一种基于二分K均值图像块聚类算法,用以实现快速构建初始训练样本库;在视频帧超分重建阶段,通过改进的最近特征线方法扩充样本库,并舍弃其中的不合适样本,提升样本库的表达能力.该视频超分辨率重建方法应用于基于关键帧的视频超分辨率重建,首先对时序上近邻的两个关键帧下采样并分块,然后使用图像块聚类算法构建初始训练样本库;对于这两个关键帧之间的低分辨率帧,使用改进的最近特征线方法扩充的训练样本库重建出对应的高分辨率帧.实验结果表明,提高了视频超分辨率重建的时间效率,同时也提升了每一帧重建图像的主客观质量,证明了算法的有效性.     

模糊聚类分析在我国各省市经济发展综合实力评价中的应用

使用模糊聚类的传递闭包法,对我国各省及直辖市进行分析,选取9个经济指标作为每个省及直辖市的特征向量,计算各特征向量的相似性,构造出模糊相似矩阵,得出传递闭包,确定λ-截集,获得动态聚类过程.和其它算法相比,该模型只需要输入少量参数及阈值,就可以较准确的对各省的数据进行分类.和其它算法的实验结果进行比较,验证出该算法的有效性和实用性.     

基于改进RPCL算法的模糊推理系统构建方法

给出了一种改进的RPCL算法,然后提出了一种基于此算法的Sugeno型模糊推理系统构造方法.该方法首先对训练样本子集聚类以形成初始模糊规则集合,然后对初始模糊规则集合再次聚类以确定模糊语言值个数和隶属函数,从而克服了以往规则提取法在训练样本不充分时规则数目难以确定及规则提取不足等缺点.最后,以倒车实验为例验证了该方法的有效性.     

支持向量机的聚类补偿研究

主要研究支持向量机方法与聚类算法的配合问题.支持向量机的训练代价太大,如果直接把成千上万个特征向量直接用作训练,运算时间难以忍受.采取的策略是用聚类算法获得较少的聚类中心,然后将聚类中心作为支持向量机的训练样本.事实上,这样的组合方式有待改进.每一聚类的样本数有多有少,所以每一个聚类中心所体现出来的权重不一样.反映在支持向量机的算法中,改进思路为:在支持向量机的训练中,除了原有点以外,加入人工样本点,人工样本点的位置就是这些原有点之一,各个位置的数量与聚类大小成比例.     

一种改进的模糊层次聚类算法

为解决模糊层次聚类算法无法收敛的问题,提出一种改进的模糊层次聚类算法.算法在分群前先进行数据处理,将特征向量相同的群合并成一个新的群,再使用模糊层次聚类算法分群,最后使用K-means算法将类簇收敛为想要的数量.实验结果表明,本算法具有较好的稳定性和分群效果,聚类质量高.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with