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61.
Phase unwrapping is a key step in retrieving digital elevation models (DEMs) from across-track interferometric synthetic aperture radar (InSAR) data. The coherence of synthetic aperture radar (SAR) data set is an effective indicator for the quality of phase unwrapping. However, the coherence of different regions usually distributes unevenly in SAR images monitoring heterogeneous areas. Errors in low-coherence areas are prone to pollute the whole image. In order to mitigate propagation error, a new phase unwrapping algorithm based on region recognition and region expansion is proposed. In the region recognition step, optical images are incorporated to recognize low-coherence regions by virtue of supervised classification technique. Low-coherence regions and the ones that are not of interest for the application are then discarded. In the region expansion step, stable pixels of high coherence are selected as growing seeds, and then phase unwrapping grows from high-quality regions to low-quality ones guided by coherence information and weighted numbers of neighbouring unwrapped pixels. The ambiguity number of a wrapped pixel is estimated from its neighbouring pixels under the criteria of pixel distance and phase gradient. Iterative examination continues until the whole image is unwrapped. Experiments on PALSAR and ASAR data demonstrate its validity and advantages over other classical methods. 相似文献
62.
This paper focuses on the methodologies to organize and structure image databases. Conventional relational database techniques are optimized to deal with textual and numeric data; however, they are not effective to handle image data. Some progresses have been made in developing new approaches to establish and use image databases, but the applications of these approaches are very labor-intensive, error-prone, and impractical to large-scale databases. In this paper, we propose a new approach to develop the structure of a large-scale image automatically. It is an integrated approach from existing technologies for the new application where the management of image data is focused. In addition, we present a solution to data indexing for the image database with different image types. 相似文献
63.
This paper proposes a new robust adaptive control method for Wiener nonlinear systems with uncertain parameters. The considered Wiener systems are different from the previous ones in the sense that we consider nonlinear block approximation error, process noise, and measurement noise. The parameterization model is obtained based on the inverse of the nonlinear function block. The adaptive control method is derived from a modified criterion function that can overcome non‐minimum phase property of the linear subsystem. The parameter adaptation is performed by using a robust recursive least squares algorithm with a deadzone weighted factor. The control law compensates the model error by incorporating the unmodeled dynamics estimation. Theoretical analysis indicates that the closed‐loop system stability can be guaranteed under mild conditions. Numerical examples including an industrial problem are studied to validate the results. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
64.
<正>"We software Automation"——登录德国3S软件公司的网站,相信这句英文一定会引起您的兴趣和关注,它精准地传递了3S软件公司的发展理念:用软件实现智能化控制。多年来,3S公司也的确以其不断发展和完 相似文献
65.
在PPT课件中使用普通方法链接的视频,如果把视频源文件删除后,链接到PPT课件中的视频就无法播放了。本文通过把视频文件转换成.swf格式文件,再利用Shockwave Flash Object控件,把.swf格式文件嵌入到PPT课件中,真正实现了视频文件的嵌入。 相似文献
66.
结合形态学和假设检验的视频对象分割 总被引:5,自引:0,他引:5
视频对象分割是当前图像和视频处理的热点和难点之一。文章首先采用形态算子和改进的watershed算法对图像序列进行空间分割,然后利用F检测算法进行帧间变化检测,将时空分割结果结合起来,得到初始的变化检测模板。通过相应的基于二值形态算子的后处理,得到最终的分割结果。整个过程基本是对灰度图像和二值模板的形态处理,简单易行。实验结果表明该算法可以较好地分离前景和背景,定位和分割视频对象。 相似文献
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69.
One of the primary objectives of sustainable manufacturing is to minimize energy consumption in its manufacturing processes. A strategy of energy saving is to adapt new materials or new processes; but its implementation requires radical changes of the manufacturing system and usually a heavy initial investment. The other strategy is to optimize existing manufacturing processes from the perspective of energy saving. However, an explicit relational model between machining parameters and energy cost is required; while most of the works in this field treat the manufacturing processes as black or gray boxes. In this paper, analytical energy modeling for the explicit relations of machining parameters and energy consumption is investigated, and the modeling method is based on the kinematic and dynamic behaviors of chosen machine tools. The developed model is applied to optimize the machine setup for energy saving. A new parallel kinematic machine Exechon is used to demonstrate the procedure of energy modeling. The simulation results indicate that the optimization can result in 67% energy saving for the specific drilling operation of the given machine tool. This approach can be extended and applied to other machines to establish their energy models for sustainable manufacturing. 相似文献
70.
传统的电极导联心脏监护仪都是有线的,接触皮肤的,高功耗的。立足于非接触性,轻便性,低功耗,给出了基于MSP430-RF无线套装的心跳监控系统的软硬件设计方法,该系统能够实时测量到人体的脉搏波形,并计算出每分钟心跳次数。系统已可实际运行,具有实时性强、低功耗、图形化界面友好的优点。 相似文献