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1.
家蚕微粒子病的图象形状特征分析   总被引:1,自引:0,他引:1  
通过对家蚕研磨后显微图象分析,提出了含微粒子图象的形状特征提取方法,并把面积,长宽比,复杂度等作为微粒子和其它组织区分的重要形状特征。  相似文献   

2.
利用计算机视觉检测家蚕微粒子病的改进研究   总被引:3,自引:2,他引:3  
在家蚕微粒子病显微图像自动识别图像分割问题中,首先应从显微图像中将微粒子从复杂背景中提取出来.由于显微图像对比度差、光照不均匀及噪音等因素的影响,采用传统的阈值分割方法和边缘检测方法不能顾及到图像局部的实际有用的目标信息,因此很难准确提取微粒子孢子区域.利用数学形态学的方法根据微粒子图像的形状特征来检测微粒子区域,实现微粒子和背景的分割,取得了较好的效果.运用基于遗传算法的BP网络进行了识别和分类,结果证明此方法是有效的.  相似文献   

3.
家蚕微粒子病病原图象分析周业为,曾传相,谢建(光电科学技术系)家蚕微粒子病蔓延极快,对蚕业生产危害极大,使丝绸业蒙受重大的经济损失,各养蚕国投入了极大的人力、物力,研究如何防治家蚕微粒子病的蔓延。一百多年来,人们一直使用法国巴斯德博士创立的母蛾人工镜...  相似文献   

4.
基于特征的图象查询和检索系统   总被引:6,自引:0,他引:6  
介绍了一个基于特征的图象查询和检索系统.该系统由查询模块、特征提取和描述模块、匹配模块、图象显示模块和图象库管理模块组成.系统既支持基于颜色、纹理、形状的单一特征查询,也支持结合不同特征的更符合视觉要求的综合特征查询.该系统已结合实际图象库进行了查询和检索实验,中给出一些实际检索结果。  相似文献   

5.
针对具封闭的几何形状的目标图象,提出了一种用几何意义明确的四特征形状因子RRRS描述目标形状的方法,用此方法描述了一类刀具图象,效果良好,证明用四特征形状因子描述具有封闭几形状的图象是可行的。  相似文献   

6.
离线中文签名鉴别的特征提取及预处理   总被引:1,自引:0,他引:1  
针对中文签名的特点,提出了一组用于离线中文签名鉴别的形状特征.同时提出了一组间接提取签名图象中动态信息的重笔道特征.两组特征综合使用,对简单模仿签名可获得错误率只有2.5%的鉴别效果.文中还介绍了中文签名图象的预处理算法.  相似文献   

7.
一种有效的SAR图象典型目标特征提取和识别方法   总被引:1,自引:1,他引:1  
在合成孔径雷达(SAR)图象中,需要对其中的人工和自然目标进行识别和分类,目标的特征提取是自动目标识别系统中的关键部分.一般图象的特征会采用颜色、纹理、形状等特征量.在SAR图象中,由于存在大量的背景噪声、目标边界模糊等问题,造成以上特征量在分类时往往不能达到很好的分类效果.作者提出了一种典型目标特征提取和分类识别方法、这种方法基于SAR成像的原理,在图象灰度阂值分割后做粗搜索分别提取灰度特征,椭圆矢量特征,以及栅格特征,然后进行SAR图象典型目标的分类识别、实验表明,这种方法效果较好.  相似文献   

8.
针对具封闭的几何形状的目标图象,提出了一种用几何意义明确的四特征形状因子RRRS(周长平方与面积之比,边界函数的变化率,平均半径的方差,形状的对称性)描述目标形状的方法,用此方法描述了一类刀具图象,效果良好,证明用四特征形状因子描述具有封闭几何形状的图象是可行的  相似文献   

9.
基于数学形态学的运动区域估计及运动图象编码   总被引:1,自引:0,他引:1  
提出了基于数学形态学的运动区域估计和运动图象编码新算法.这种算法利用数学形态变换提取帧间物体运动块和运动区域,并进行自然形状对应的区域匹配和运动补偿.实验表明,与MPEG等分块运动补偿相比,本算法运动匹配准确,搜索快速,避免了方块效应,在相同码率下较好地改善了图象质量,特别适用于低码率运动图象编码.  相似文献   

10.
目前,高分辨率遥感图象正愈来愈多地应用于土地与水资源的监测和管理,其中,IKONOS图象数据因其具有较高的空间分辨率和人机交互的解译效果.在省市土地利用信息获取及在城市研究中更具有广阔的应用前景.以南京幅的IKONOS图象数据为基础.以城乡接合部的不同试验区为对象,着重讨论了高分辨率遥感图象城市土地利用信息的提取与分类方法其主要思想是先应用常用的多光谱分类算法对试验区的土地利用现状进行初始的类别划分,然后采用Majority Filtering技术获取图象的上下信息,并给你根据地物的形状特征和空间关系对初始分类结果进行校正与调整.研究结果表明,当初始的类别划分能满足一定精度时,采用本所提出的方法能进一步改善高分辨率图象城市土地利用信息的分类效果.  相似文献   

11.
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.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
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.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
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.  相似文献   

14.
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.  相似文献   

15.
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。  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
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-  相似文献   

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