高分辨率极化SAR影像KummerU分布非监督分类方法

针对高分辨率极化SAR数据特征分布不再符合同质区域假设, 进而导致基于统计分布的极化SAR影像非监督分类方法精度下降的问题, 将具有广泛适用性的KummerU分布嵌入粒子群寻优聚类算法, 提出了新的极化SAR影像非监督分类算法(PSO-KummerU方法):首先基于极化SAR统计特征对数据进行初分类, 然后采用极化SAR统计特征与粒子群优化算法进一步进行聚类中心求解, 分类准则部分采用KummerU距离改进代替传统的Wishart距离度量准则; 采用3种非监督分类方法(H/α-Wishart、PSO-Wishart、PSO-KummerU方法)进行分类对比实验.实验结果表明:基于KummerU分布的PSO-KummerU方法与采用Wishart距离的聚类方法相比, 目视效果明显改进, 整体分类精度提高14%以上.     

顾及邻域空间约束的极化SAR图像模糊聚类算法

传统模糊聚类算法对噪声敏感、未考虑邻域像素的信息,分割效果不理想。为提高算法对噪声的鲁棒性和分类精度,该文通过引入像素的邻域信息来改进目标函数。并且根据极化数据的分布特性,采用Wishart距离替代欧式距离,增强了对数据的非相似性测度能力。采用真实的极化SAR数据来验证算法的有效性。实验结果表明算法能够有效抑制噪声,取得了较好的分类结果,分类精度可达94.5%。     

基于Meanshift和图割的极化特征图像分类

图割法对极化SAR图像能达到很好的分类效果,但由于极化SAR数据比较庞大,直接用图割法进行分类,计算量太大,所以本文提出一种改进图割模型的分类方法．首先利用自适应的Meanshift算法结合多个极化特征把图像分成若干个同质区域,以这些同质区域的加权平均值作为超像素构建图模型,最后用图割法修正Meanshift过分割来得到最终的分类．实验证明该算法不仅在分类精度上有所提高,而且在速度上更能达到实时性的要求．     

基于样本选择策略的SAR图像半监督分类算法

针对当前SAR图像半监督协同训练分类算法受相干斑噪声干扰等问题,本文提出了基于选择策略的SAR图像半监督分类方法.该方法首先以超像素为基本单元,在获取伪样本过程中,利用典型相关性分析作为SAR图像高置信度样本补充判别器,而对于低置信度样本,提出基于超像素和主动学习的样本扩充方法,然后基于扩充后的样本实现SAR图像的半监督分类;最后通过理论分析和实验验证了该方法在标注样本较少的情况下,取得了较好的效果和精度,降低了相干斑噪声对分类效果的影响.     

基于分水岭与多尺度相结合的影像分割方法

分水岭分割是一种应用较广泛的影像分割方法,它能自动生成单像素宽度的封闭轮廓,但需要把影像分割成过多小区域,从而导致影像分割耗时且工作量大。本文就此提出一种分水岭和多尺度相结合的高分辨率影像分割方法。该方法首先运用分水岭方法对融合了亮度梯度和纹理梯度的综合梯度进行计算,然后将同质性度量值最小的区域对合并,最后结合改进区域邻接图进行区域合并。实验结果与基于分水岭和区域合并的影像分割算法得到的结果进行比较,证明该方法不仅能充分利用高分辨率遥感影像中地物的光谱、形状、纹理等特征,而且减少了计算时间。     

一种基于Pauli分解和SVM的全极化SAR监督分类算法

全极化SAR影像准确分类的一个重要前提是充分提取反映地物实际物理性质的特征。然而现有的全极化SAR特征提取算法和分类算法众多,却均存在各种各样的问题。无论极化特征提取方法还是分类算法,都会影响最终的分类精度。针对此问题,在多次实验的基础上,提出一种综合Pauli极化特征分解和SVM的分类策略,简称为Pauli-SVM算法。首先通过经典的Pauli分解法提取全极化SAR影像的奇次散射、偶次散射、体散射等极化特征,并将这些信息组合成一个特征向量,然后引入高精度的SVM分类算法,选择训练样本后对全极化SAR影像进行监督分类。在江苏溧水和南京横溪镇两个研究区,以ALOS卫星的PALSAR影像为研究数据,进行监督Wishart分类算法、Freeman特征提取法结合SVM的分类算法、Yamaguchi特征提取法结合SVM的分类算法、Pauli-SVM算法的分类对比实验。结果表明,新提出的Pauli-SVM算法可以有效的提高分类的准确性。     

一种基于Pauli分解和支持向量机的全极化合成孔径雷达监督分类算法

全极化合成孔径雷达(SAR)影像准确分类的一个重要前提是充分提取反映地物实际物理性质的特征。然而现有的全极化SAR特征提取算法和分类算法众多,却均存在各种各样的问题。无论极化特征提取方法还是分类算法,都会影响最终的分类精度。针对此问题,在多次实验的基础上,提出一种综合Pauli极化特征分解和支持向量机(SVM)的分类策略,简称为Pauli-SVM算法。首先通过经典的Pauli分解法提取全极化SAR影像的奇次散射、偶次散射、体散射等极化特征;并将这些信息组合成一个特征向量,然后引入高精度的SVM分类算法,选择训练样本后对全极化SAR影像进行监督分类。在江苏溧水和南京横溪镇两个研究区,以ALOS卫星的PALSAR影像为研究数据,进行监督Wishart分类算法、Freeman特征提取法结合SVM的分类算法、Yamaguchi特征提取法结合SVM的分类算法、Pauli-SVM算法的分类对比实验。结果表明,新提出的PauliSVM算法可以有效地提高分类的准确性。     

采用联合域字典稀疏表示的极化SAR图像分类

针对传统字典学习算法难以有效保持极化SAR图像的空间结构以及难以处理大规模数据的问题,提出了一种基于空域和极化域的联合域字典学习和稀疏表示的分类方法.该方法采用基于联合域流形距离的快速AP聚类进行字典学习.利用局部线性编码对极化SAR图像进行空域和极化域的联合域稀疏表示,充分利用了极化SAR数据集潜在的信息,有效保持极化SAR数据结构的同时降低了算法的时间复杂度.试验结果表明:所提算法适应性强,收敛速度快,能够提高极化SAR图像的分类精度.     

基于超像素分割的图注意力网络的高光谱图像分类

针对卷积神经网络(CNN)仅能应用于欧氏数据,无法有效获取像素间的全局关系特征以及长距离上下文信息的问题,构建一个基于超像素分割的图注意力网络SSGAT.该网络将超像素分割后的超像素块视为图结构中的图节点,有效减少了图结构的复杂度,并降低了分类图的噪声.在3个数据集上对SSGAT及对比算法的分类精度进行测试,分别获得了94.11%,95.22%,96.37%的总体分类精度.结果表明该方法性能优异,在处理大尺度区域的分类问题时优势明显.     

基于极化SAR的城市建筑物提取

城市建筑物信息与人类的生存息息相关,建筑物信息的提取在很多社会领域和科学领域都有着非常重要的意义。全极化SAR影像比单极化SAR影像所包含的信息量丰富的多,为了保证建筑物提取精度,本文利用全极化SAR影像提取城市建筑物信息。将经典的H/α/A-Wishart分类方法引入建筑物提取的研究中,不仅快捷简便,且能保证提取精度。选择一景极化SAR影像进行实验,由于实验数据自身的质量以及研究区域建筑物分布问题都对建筑物提取造成困难,尽管如此,利用该方法仍然保证了一定的建筑物提取精度。     

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.