遗传算法与改进的FCM聚类算法的结合

模糊C-均值聚类(FCM)对初始值很敏感,易于陷入局部极小点而不能搜索到全局的聚类中心,而遗传算法是一种全局搜索方法,本文通过改变隶属度约束条件由FCM算法得到一种新的模糊聚类算法PCM,并将其与遗传算法相结合。实验结果表明,这种方法明显优于传统FCM算法。     

基于人工蜂群的模糊聚类算法

针对模糊C-均值(FCM)聚类算法存在容易陷入局部极小值、对初始值和噪声数据敏感的缺点,提出一种基于人工蜂群(ABC)的模糊聚类算法(ABFM).该算法引入全局寻优能力强的人工蜂群算法来求得最优解作为FCM算法的初始聚类中心,然后利用FCM算法优化初始聚类中心,最后求得全局最优解,从而有效克服了FCM算法的缺点.实验结果表明,新算法与FCM聚类算法相比,提高了算法的寻优能力,并且迭代次数更少,收敛速度更快,聚类效果更好.     

基于GA与PSO并行的模糊聚类算法

针对FCM算法不足,提出一种改进的模糊聚类算法:基于遗传算法(GA)与粒子群优化算法(PSO)并行的模糊聚类算法.实验结果表明,该算法比单基于GA或者PSO的模糊聚类有较好分类正确率与稳定性,有效克服了传统FCM算法对初值敏感和易陷入局部极小值的问题.     

改进的FCM在人脑MR图像分割中的应用

为解决模糊C-均值聚类(FCM)算法在图像分割尤其是医学图像分割中存在的计算量大、运行时间过长的问题,提出了一种改进方法。利用收敛速度快的K均值聚类法得到的聚类中心作为FCM算法的初始聚类中心,减少FCM算法收敛所需的迭代次数;优化参与迭代运算的数据集,减少每次迭代过程的运算时间。该方法使FCM算法的运算速度提高了将近10倍,而且不会影响算法的分割效果。     

一种基于遗传算法的模糊C均值算法

模糊C-均值聚类(FCM)对初始值很敏感,易于陷入局部极小点而不能搜索到全局的聚类中心,遗传算法是一种通过模拟自然进化过程的搜索最优解的方法.因此,将FCM算法引入遗传算法的进化中,代替原来的交叉操作.实验结果表明,新方法明显优于传统 FCM算法.     

FCM聚类算法与改进层次聚类算法的结合

模糊c-均值聚类算法(fuzzy C-means 简称FCM)和层次聚类算法是两种非常重要的聚类算法.由于FCM算法对初始聚类中心敏感,并且需要人为确定聚类类别数,这样收敛结果易陷入局部最优解.通过对这两种聚类算法的分析,首先对传统的凝聚层次聚类算法提出了改进,然后用改进的凝聚层次聚类算法得到最佳聚类数和初始聚类中心,最后用FCM算法进行再次聚类,以此得到更好的聚类结果并且减少了执行时间和迭代次数.     

基于改进遗传算法的模糊C均值聚类算法

针对传统模糊C均值聚类算法(FCM)的缺陷,提出了一种基于改进遗传算法的模糊聚类方法.利用改进遗传算法强大的全局寻优能力,这种算法较好地克服了FCM算法对初始化敏感、容易陷入局部最优的缺陷.仿真实验证明,该算法具有较强的全局寻优能力和较快的收敛速度.     

基于GA和FCM的岩体结构面的混合聚类方法

提出了一种基于遗传算法(GA)和模糊C均值(FCM)算法的岩体结构面混合聚类方法.利用GA的全局搜索性能,求得初始聚类中心:在此基础上利用FCM算法,根据精度要求再作进一步求解.该方法避免了人为划定分类界限的主观性,消除了FCM聚类算法的局部最优的弱点,解决了采用普通遗传算法聚类时搜索速度和聚类精度的矛盾.结合实测数据,对应用该方法进行结构面组识别的步骤、参数选取、分组有效性、优势方位的判定进行了分析和讨论.     

基于遗传算法的截集FCM灰度图像分割方法研究

以截集模糊C均值聚类（Sectional Set Fuzzy C—means algorithm：SSFCM）算法为基础，提出一种自适应遗传算法（Adaptive Genetic Algorithm）改进截集FCM算法。传统FCM算法中一般使用一维直方图初始化方法，使初始化与聚类算法相分离，没有形成整体，而且同一幅一维直方图可能对应不同的原始图像。引入自适应遗传算法，与截集FCM算法有机结合，用遗传算法解决初始化问题的同时．以遗传算法的寻优性能来指导聚类。实验表明，该算法效率较传统FCM算法和未改进截集FCM算法有很大的提高，同时能够保持较好的分割效果和质量。     

基于模糊c-均值算法和遗传算法的新聚类方法

为了得到最佳聚类数和相应的每一类中的样本,文中首先介绍了一种新聚类方法,用该方法构造了一个既考虑类与类之间的分散程度、又考虑同一类紧凑程度的目标评价函数;再运用模糊c-均值算法(FCM)进行迭代,求得每一类的中心和隶属度值;然后运用遗传算法搜索全局极值点;最后运用该算法对我国全要素生产力进行了模糊分类．     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

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