一种Roberts自适应边缘检测方法

针对Roberts算法对噪声比较敏感且需要人为指定阈值等问题,提出了一种Roberts自适应边缘检测方法.利用Roberts算子的基本原理,扩充了检测方向,再根据待检像素周围的3×3像素邻域的平均像素灰度值,结合人眼视觉特征自适应地生成动态阈值,这样既保留了原Roberts算子的可并行处理、快速运算、边缘较细等优点,还对噪声有一定的抑制作用.同时,针对Roberts算法边缘检测相对粗糙、边缘细化效率较低的问题,分析和改进了原有边缘细化算法,即先对含有噪声的图像进行边缘检测,过滤其伪边缘,再对图像边缘进行细化处理,从而得到单像素边缘.实验比较表明,所提算法能够自适应地生成动态阈值,提高图像边缘细节信息的提取性能.     

利用贫富差距原理进行图像边缘检测

针对Robinson算法运算速度慢且需要人为指定闲值等问题,提出了一种Robinson自适应边缘检测算法.该算法利用Robinson基本原理删除了一些算法模板,根据计算贫富差距的原理得到像素的梯度值,从而可以进一步提高抑制噪声的能力.算法依据待检测像素周围3×3邻域的像素平均灰度值,结合人眼的视觉特征自适应地生成动态阈值,不仅保留了原Robinson算法可并行处理、能够抑制噪声等优点,还提高了运算速度和抑制噪声的能力.实验表明,所提算法在图像处理中能够自适应地生成动态阈值,提高图像的细节信息提取和噪声抑制的性能.     

自适应Kirsch边缘检测算法

针对Kirsch算法容易丢失弱边缘.且需要人为指定阈值等问题.提出了一种自适应Kirsch边缘检测算法.利用Kirsch基本原理,根据待检测像素周围的3×3邻域的像素平均灰度值,结合人眼的视觉特性自适应地生成动态阈值,这样既保留了原Klrsch算法可并行处理、能够抑制噪声等优点,还可以检测到弱边缘.同时,针对Kirsch算法所得边缘相对粗糙、边缘细化算法效率较低的问题,分析和改进了原有边缘细化算法.可以得到单像素边缘.通过实验比较.所提算法实验效果比较珲想.     

复杂海面环境下船只边缘识别算法的改进

针对复杂海面环境下船只边缘识别问题,提出了一种融合Retinex图像去雾预处理和改进自适应阈值SUSAN边缘检测的算法,用来提取船只目标边缘特征.对由于不同场景海雾造成的图像模糊,采用Retinex预处理增强图像信息,然后对待检测目标像素剔除伪边缘点,采用自适应算法获取几何阈值t和最大类间方差(Otsu)的方法选取双阈值g,进而对图像进行边缘点检测、提取边缘特征.实验结果表明,融合后的算法能够有效提高复杂海面船只边缘检测的鲁棒性.     

自适应双阈值Canny算子的图像边缘检测

为解决Canny算子进行图像边缘检测中双阈值的求取需要人工设定的问题,提出了自适应双阈值算法,这样可以针对不同图像实现双阈值的自适应提取,再通过控制技术明确边缘像素,使应用Canny算子检测图像边缘成为现实。经仿真实验表明本算法是有效的。     

基于惯性原理的图像边缘检测技术

针对Canny算法对噪声比较敏感,检测到的边缘不够光滑,且需要人为指定高、低阈值等问题,提出了一种自适应Canny边缘检测算法。首先,利用Canny算子的基本原理,提出了一种计算梯度的新方法;然后,根据图像梯度信息自适应地生成高、低阈值;最后,根据惯性原理进行边缘跟踪,使边缘更光滑。实验结果表明:该算法不仅能够根据图像梯度信息自适应地生成高、低阈值,还保留了原Canny算法的定位准确的优点,对噪声还具有一定的抑制作用。     

基于改进Sobel算子的多仪表图像边缘检测算法

为了解决Sobel算子在多仪表图像检测中存在的边缘定位精度不高、提取边缘较粗以及对噪声敏感等缺点,提出了一种改进算法。首先在原有水平和垂直模板的基础上新增6个方向模板,提高了边缘定位精度,使其适用于纹理结构复杂的图像。然后根据图像的具体特征自适应确定阈值,有效去除图像的伪边缘。最后结合数学形态学的灰度腐蚀理论,对检测到的边缘进行细化处理。不仅能获得细化效果较好的边缘,同时可以有效的抑制噪声。实验结果表明:改进后的算法对图像噪声干扰有较强的抑制能力,提取的边缘定位准确、结构细腻。     

自适应迭代维纳滤波算法

针对经典维纳滤波去除图像高斯噪声后不能很好保持图像边缘和平滑性的问题,提出一种自适应迭代维纳滤波算法。首先,依靠像素灰度值的二阶差分分量估计图像的噪声方差;然后,以3×3大小的模板为起始模板,对图像进行迭代滤波且每次迭代都增加模板大小;最后,每次滤波前后所有像素灰度值变化大小的均值是否小于阈值为停止迭代的判断条件,判断条件成立结束滤波。不同改进算法的实验结果对比,该改进算法不仅保持较高图像峰值信噪比而且在时间复杂度上要小于小波域维纳滤波器,并且在保持图像边缘和平滑效果方面要较好于小波域维纳滤波。     

基于改进Canny算法的服装图像边缘检测

针对传统Canny算法在噪声去除与高低阈值选取方面存在的问题,提出一种改进的Canny算法应用于服装图像边缘检测上,首先使用改进中值滤波取代高斯滤波进行服装图像去噪,然后采取在像素八邻域内计算梯度幅值的方法计算梯度的幅值和方向并获取非极值抑制后的图像数据阵列,最后利用Otsu算法计算高低阈值并连接边缘.实验结果表明,改进算法能够有效的抑制噪声并检测出较完整清晰的服装边缘.     

基于自适应Canny的红外图像边缘检测算法

针对Canny算法需要人工设定高斯方差值和双阈值,红外图像存在噪声大、边缘模糊等缺点,提出一种基于自适应Canny的红外图像边缘检测算法.该算法采用自适应中值滤波代替高斯滤波计算梯度的幅值和方向,对梯度的幅值在3×3邻域内进行非极大值抑制,并根据图像灰度使用Otsu算法,自适应获取高低阈值,用高低阈值算法检测和连接边缘.实验结果表明,该算法减小了均方误差,提高了峰值信噪比和平均结构相似度,能有效提取红外图像边缘.     

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