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.     

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。     

基于半监督的模糊C-均值聚类算法

通过将半监督学习的思想引入到模糊C-均值聚类方法中,提出一种基于半监督的模糊C-均值聚类算法,有效解决了模糊C-均值聚类算法随机选取初始聚类中心导致聚类结果局部收敛的问题,能客观获取最佳聚类数目和初始聚类中心.实验结果表明,与传统模糊C-均值聚类算法相比,基于半监督的模糊C-均值算法在一定程度上减少了迭代次数,降低了对初始聚类中心的依赖性.     

基于PSO的模糊C均值聚类算法

在分析模糊C均值聚类算法存在不足的基础上,提出了一种新的聚类算法:基于粒子群的模糊C均值聚类算法.该算法利用粒子群强大的全局寻优能力,不仅克服了传统的模糊C均值聚类算法对初始值敏感、噪声数据敏感、易陷人局部最优的问题,而且有较快的收敛速度.试验证明,这种算法是一种很有潜力的模糊聚类算法.     

基于改进粒子群的模糊聚类超声图像分割

医学超声图像由于存在斑点噪声等模糊和不确定性的特点使得分割一直是一个难题。模糊C-均值聚类算法是一种结合无监督聚类和模糊集合概念的技术,广泛应用于图像分割,但存在着受初始聚类中心和目标函数高度非线性影响,极易收敛到局部极小的缺点。将集群智能的粒子群优化算法(PSO)与模糊C-均值聚类算法相结合,实现了基于粒子群模糊C-均值聚类的图像分割算法。实验结果表明,该方法具有搜索全局最优解的能力,因而可得到很好的图像分割结果。     

一种基于粒子群的模糊聚类图像分割算法

针对图像分割特征具有交叉重叠现象、其类属的划分存在不确定性的分割问题,模糊聚类分割算法具有较强的优势,但其速度慢且容易陷入局部最优以及对初始值的设置敏感等问题.根据粒子群优化算法具有全局寻优能力,同时还具有较强的局部寻优能力,能更快收敛于最优解的特点,提出了一种基于粒子群的模糊聚类分割算法.实验证明,该算法相比传统的模糊聚类分割算法,具有更快的收敛速度和更高的分割精度.     

一种鲁棒的无监督聚类图像分割算法

针对目前基于模糊C-均值聚类图像分割算法的噪声敏感问题, 提出一种基于无监督可能性聚类的自动加权图像分割算法. 该算法先应用均值漂移迭代确定可能性C-均值聚类算法的初始化中心, 利用可能性聚类的模式搜索性质自动确定聚类划分; 然后根据像素间灰度值关系进行图像加权, 通过将加权系数与像素噪声的可能性相关联, 降低噪声对图像分割的影响. 实验结果表明, 相对于基于模糊C-均值聚类的图像分割算法, 该算法不仅取得了较好的分割效果, 而且无监督分割时计算效率更高, 对噪声的鲁棒性更强.     

一种鲁棒的无监督聚类图像分割算法

针对目前基于模糊C-均值聚类图像分割算法的噪声敏感问题, 提出一种基于无监督可能性聚类的自动加权图像分割算法. 该算法先应用均值漂移迭代确定可能性C-均值聚类算法的初始化中心, 利用可能性聚类的模式搜索性质自动确定聚类划分; 然后根据像素间灰度值关系进行图像加权, 通过将加权系数与像素噪声的可能性相关联, 降低噪声对图像分割的影响. 实验结果表明, 相对于基于模糊C-均值聚类的图像分割算法, 该算法不仅取得了较好的分割效果, 而且无监督分割时计算效率更高, 对噪声的鲁棒性更强.     

模糊C-均值聚类算法的改进研究

模糊C-均值聚类算法通过迭代的爬山技术来寻找问题的最优解,是一种局部搜索算法,容易受初始值的影响而陷入局部极小值.遗传算法是一种应用广泛的全局优化算法,是一种与求解问题无关的算法模式,能够有效解决模糊C-均值聚类算法对初始化敏感的问题,利用改进后的遗传算法能更好地解决聚类问题.     

边缘信息指导下的半模糊聚类图像分割方法

提出了一种利用边缘信息的半模糊均值聚类的图像分割算法，它先用边缘检测和区域生长算法对图像进行一次预分割，确定聚类的初始参数，然后在这个基础上对“边缘”部分的点采用模糊聚类、非“边缘”部分使用分明聚类，避免了模糊聚类时初始参数设定的盲目性，减少了迭代时的计算量，提高了迭代收敛速度．除灰度特征外，聚类时还利用了点到类的距离特征，较好地保持了分割图像的连续性．直接观察对比多幅图像的分割实验结果可以明显地发现，该算法较常用的Cksu方法、二维熵阈值分割方法以及FCM方法的分割结果更准确．就Lena图像而言，该算法的收敛速度也比一般的FCM快了将近一倍．     

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.     

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.     

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

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.     

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.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

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。     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

Quality traits in wheat （Triticum aestirum L.） were studied by quantitative trait locus （QTL） analysis in a recombinant inbred line （RIL） population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross （ChSh）. Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.