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Number of results: 4
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Abstract

Cardiovascular system diseases are the major causes of mortality in the world. The most important and widely used tool for assessing the heart state is echocardiography (also abbreviated as ECHO). ECHO images are used e.g. for location of any damage of heart tissues, in calculation of cardiac tissue displacement at any arbitrary point and to derive useful heart parameters like size and shape, cardiac output, ejection fraction, pumping capacity. In this paper, a robust algorithm for heart shape estimation (segmentation) in ECHO images is proposed. It is based on the recently introduced variant of the level set method called level set without edges. This variant takes advantage of the intensity value of area information instead of module of gradient which is typically used. Such approach guarantees stability and correctness of algorithm working on the border between object and background with small absolute value of image gradient. To reassure meaningful results, the image segmentation is proceeded with automatic Region of Interest (ROI) calculation. The main idea of ROI calculations is to receive a triangle-like part of the acquired ECHO image, using linear Hough transform, thresholding and simple mathematics. Additionally, in order to improve the images quality, an anisotropic diffusion filter, before ROI calculation, was used. The proposed method has been tested on real echocardiographic image sequences. Derived results confirm the effectiveness of the presented method.

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Authors and Affiliations

Andrzej Skalski
Paweł Turcza
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Abstract

A new solar tracking sensor based on image recognition is proposed and designed to solve the problem of low accuracy of photoelectric tracking in photovoltaic power generation. The sensor can directly output its angular deviation from the sun, and its mechanical structure and working principle are analysed in detail. We use a high-precision camera to collect the image of the two slots on the projector surface and use the Hough transform to identify the image of the light seam. After obtaining the linear equation for the two slots, the coordinate of the intersection point is found, and the calculation of the solar altitude and azimuth can be realized. We have improved the Hough transform scheme by using the skeleton image of the slots instead of the edge image. The improvement of the scheme has been proved to effectively improve the detection accuracy. A calibration test board is used to test the sensor and experimental results show that the scheme can achieve the measurement of azimuth and altitude with the accuracy of be 0.05°, which can meet the detection accuracy requirements of the solar tracking in photovoltaic power generation and many other photoelectric tracking implementations.
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Authors and Affiliations

Jianjun Lan
1

  1. Fujian Vocational & Technical College of Water Conservancy & Electric Power, School of Electric Power Engineering, Yongan 366000, China
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Abstract

This article presents a method for detecting linear objects with a defined direction based on image and lidar data. It was decided to use Gabor waves for this purpose. The Gabor wavelet is a sinusoid modulated by the Gauss function. The orientation angle of the sinusoid means that the waveform can only operate in strictly defined directions. It should, therefore, provide an appropriate solution to the problem posed by the publication. The research problem focused in the first stage on determining the approximate location of only the analysed objects, and in the next step on correct and accurate detection. The first stage was carried out using Gabor filters, the second - using the Hough transform. The tests were performed for both laser data and image data. In both cases, good results were obtained for both stages: approximate location and precise detection.

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Authors and Affiliations

Urszula Marmol
Natalia Borowiec
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Abstract

Driver assistance systems have started becoming a key differentiator in automotive space and all major automotive manufacturers have such systems with various capabilities and stages of implementation. The main building blocks of such systems are similar in nature and one of the major building blocks is road lane detection. Even though lane detection technology has been around for decades, it is still an ongoing area of research and there are still several improvements and optimizations that are possible. This paper offers an Optimized Dynamic Origin Technique (Optimized DOT) for lane detection. The proposed optimization algorithm of optimized DOT gives better results in performance and accuracy compared to other methods of lane detection. Analysis of proposed optimized DOT with various edge detection techniques, various threshold levels, various sample dataset and various lane detection methods were done and the results are discussed in this paper. The proposed optimized DOT lane detection average processing time increases by 9.21 % when compared to previous Dynamic Origin Technique (DOT) and 59.09 % compared to traditional hough transform.
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Authors and Affiliations

P. Maya
1
C. Tharini
1

  1. B S Abdur Rahman Crescent Institute of Science and Technology, Chennai, India

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