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A novel technique for binarization with stroke preservation of faint characters in degraded documents is proposed. It works in a multi-scale framework with an adaptive–interpolative thresholding technique. Instead of computing a global threshold value, it computes the local threshold values for a small set of grid points by observing the intensity pattern of the pixels lying in the concerned grid cells. Estimated thresholds are used, in turn, to compute the threshold values of all the remaining pixels using a fast-yet-efficient interpolation procedure. To handle noises in degraded images, this grid-based adaptive thresholding is applied in successively reducing scales to obtain the near-optimal binarization as a set of connected components. After a post-processing meant for stroke preservation with these connected components, we get the final output. Exhaustive experimentation and comparison with other existing methods have been successfully carried out with benchmark datasets and also with our own datasets. 相似文献
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We present a method for mapping the spatial distribution of viscoelastic properties of heterogeneous samples using the atomic force microscope (AFM). By applying a force step load protocol to induce time dependent sample indentations we measured the local creep compliance of the sample. The creep compliance was quantified in terms of the standard linear solid model to give maps of the instant glassy modulus, the equilibrium rubbery modulus, and the retardation time. To reduce the influence of plastic deformations, the sample was preformed with an initial preload step. Different polymer samples with a homogeneous or a heterogeneous material composition on a microscopic scale were investigated. 相似文献
35.
目前油田套损注水井使用常规小直封隔器无法实现反洗井、使用可洗井封隔器反洗井时不能有效封堵套损点,为此研制了注水井套损部位可洗井封堵工具,实现可反洗井和对套损点的有效封堵。该封堵工具在注水井套损补贴管处使用上、下两个可洗井封堵工具,采用大、小两组胶筒的结构设计,内设洗井通道,反洗井时能够保证对套损点的有效封堵。 相似文献
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介绍了苏州古典园林植物,从其植物的选用特点及配置特点两方面进行了论述,指出苏州古典园林充分发挥出了自身的地域特色,创造出了风格鲜明的江南园林,形成了我国古代历史上私家园林的代表流派。 相似文献
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传统山地建筑视觉造型分析 总被引:1,自引:0,他引:1
传统山地建筑是人们在长期实践经验的积累下发展起来的一类建筑形式。这类建筑巧妙地利用山地地形来建造,在视觉造型艺术上有着独特的风格和魅力。本文分析了传统山地建筑视觉造型特征,希望对山地建筑创作有所启发。 相似文献
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Using visual assessment as a foundation for greenway planning in the St. Lawrence River Valley 总被引:2,自引:0,他引:2
The growth of the ‘greenway’ as a fundamental planning concept has provided guidance for many communities locally and around the world. In the St. Lawrence River Valley, the idea is providing a common physical and cultural reference for the management of landscapes in communities along a 100 mile international corridor. Over the past 10 years, the College of Environmental Science and Forestry of the State University of New York has worked with the St. Lawrence-Eastern Ontario Commission to examine the unique visual and scenic resources of the region as the foundation for establishing a greenway tracing the St. Lawrence River. Although the idea of a greenway in the St. Lawrence River Valley is not new or unusual, the inventory and assessment of visual or scenic linear resources as a foundation is a departure from typical practice, and an experiment in defensible and rational planning. As a major summer tourism destination, the region is well aware of the critical value of its scenic resources. In our effort to identify and assess various vital resources for planning, we found an indicator in the visual nature of the landscape—both as a resource in and of itself, and as a reflection of the underlying values held by local communities for natural and cultural resources. This paper describes, as a case study, the process used to identify and assess visual and scenic resources in the region, and the use of the resulting database to initiate delineation of the proposed greenway. A discussion of the rationale and significance of the method is presented, including comments on the direction and progress in the region today. 相似文献
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因岭而兴的湖北古镇--钟祥张集 总被引:1,自引:1,他引:1
该文从湖北钟祥张集古镇特殊的地理环境背景出发,分析了"枕山环水"的选址特色,"三山·两河·一老街·一新区"的空间格局以及"两关三巷六门"的防卫型布局特点,研究了街巷空间尺度,双重檐建筑特色及排水系统. 相似文献