Irradiation angle dependence and polarization dependence in 3D geometry measurement using AMCW LiDAR

Author(s):  
Chao Zhang ◽  
Neisei Hayashi ◽  
Sze Yun Set ◽  
Shinji Yamashita
Author(s):  
Lorenz Quentin ◽  
Rüdiger Beermann ◽  
Kai Brunotte ◽  
Bernd-Arno Behrens ◽  
Markus Kästner ◽  
...  

2017 ◽  
Author(s):  
Lorenz Quentin ◽  
Rüdiger Beermann ◽  
Andreas Pösch ◽  
Eduard Reithmeier ◽  
Markus Kästner

2001 ◽  
Author(s):  
Huijie Zhao ◽  
Jun Ni ◽  
Yi Sun ◽  
Xuewen Lin

Sensors ◽  
2019 ◽  
Vol 19 (5) ◽  
pp. 1074 ◽  
Author(s):  
Piotr Siekański ◽  
Krzysztof Magda ◽  
Krzysztof Malowany ◽  
Jan Rutkiewicz ◽  
Adam Styk ◽  
...  

The paper presents the automated on-line system for wood logs 3D geometry scanning. The system consists of 6 laser triangulation scanners and is able to scan full wood logs which can have the diameter ranging from 250 mm to 500 mm and the length up to 4000 mm. The system was developed as a part of the BIOSTRATEG project aiming to optimize the cutting of logs in the process of wood planks manufacturing by intelligent positioning in sawmill operation. This paper illustrates the detailed description of scanner construction, full measurement process, system calibration and data processing schemes. The full 3D surface geometry of products and their applied portion of selected wood logs formed after cutting out the cant is also demonstrated.


Author(s):  
Kenta Yamagiwa

In this study, the three-dimensional geometry of simulated corrosion surface was compared with that of actual corrosion surface by use of fractal concept that was useful to understand the feature of self-similar pattern. To discuss the difference, fractal dimension (Fd) and fractal boundary (λb) are used. The method to make the simulated surface was that the nitric acid was dropped on steel (JIS SB410) plate to make a dimple on it by corrosion. The actual corrosion surface was provided from the piping which used in the actual chemical plant. To calculate Fd and λb of these corrosion surfaces, three-dimensional geometry was measured by the 3D-geometry measurement system (Keyence VR-3000). The measured size was respectively about 90×60mm (4000×3000 pixels). Next, wavelet transform was applied to the three-dimensional geometry. Fd and λb were calculated from the wavelet coefficient instead of the power spectrum. The mother wavelet was the Gabor function that is the combination of sinusoidal wave and Gaussian function. In the result, the difference of Fd between the simulated surface and the actual surface was obtained. The average Fd of the simulated surface was about 2.2. On the other hand, the average Fd of the actual surface was more than 2.6. It means the actual surface is more complex than the simulated surface. The λb of the actual surfaces was not obtained, because the linier relationship was satisfied in every frequency. However, the λb of the simulated surface was about 1cm. It was similar to the dimple’s diameter. Therefore, there is a difference between the simulated surface and the actual surface by applying the concept of fractal though they look similar by the human observation. The relationship between the burst pressure, Fd and λb will be discussed.


Author(s):  
T. Oikawa ◽  
M. Inoue ◽  
T. Honda ◽  
Y. Kokubo

EELS allows us to make analysis of light elements such as hydrogen to heavy elements of microareas on the specimen. In energy loss spectra, however, elemental signals ride on a high background; therefore, the signal/background (S/B) ratio is very low in EELS. A technique which collects the center beam axial-symmetrically in the scattering angle is generally used to obtain high total intensity. However, the technique collects high background intensity together with elemental signals; therefore, the technique does not improve the S/B ratio. This report presents the experimental results of the S/B ratio measured as a function of the scattering angle and shows the possibility of the S/B ratio being improved in the high scattering angle range.Energy loss spectra have been measured using a JEM-200CX TEM with an energy analyzer ASEA3 at 200 kV.Fig.l shows a typical K-shell electron excitation edge riding on background in an energy loss spectrum.


Endoscopy ◽  
2004 ◽  
Vol 36 (10) ◽  
Author(s):  
BP McMahon ◽  
JB Frøkjær ◽  
A Bergmann ◽  
DH Liao ◽  
E Steffensen ◽  
...  

2019 ◽  
Vol 63 (5) ◽  
pp. 50402-1-50402-9 ◽  
Author(s):  
Ing-Jr Ding ◽  
Chong-Min Ruan

Abstract The acoustic-based automatic speech recognition (ASR) technique has been a matured technique and widely seen to be used in numerous applications. However, acoustic-based ASR will not maintain a standard performance for the disabled group with an abnormal face, that is atypical eye or mouth geometrical characteristics. For governing this problem, this article develops a three-dimensional (3D) sensor lip image based pronunciation recognition system where the 3D sensor is efficiently used to acquire the action variations of the lip shapes of the pronunciation action from a speaker. In this work, two different types of 3D lip features for pronunciation recognition are presented, 3D-(x, y, z) coordinate lip feature and 3D geometry lip feature parameters. For the 3D-(x, y, z) coordinate lip feature design, 18 location points, each of which has 3D-sized coordinates, around the outer and inner lips are properly defined. In the design of 3D geometry lip features, eight types of features considering the geometrical space characteristics of the inner lip are developed. In addition, feature fusion to combine both 3D-(x, y, z) coordinate and 3D geometry lip features is further considered. The presented 3D sensor lip image based feature evaluated the performance and effectiveness using the principal component analysis based classification calculation approach. Experimental results on pronunciation recognition of two different datasets, Mandarin syllables and Mandarin phrases, demonstrate the competitive performance of the presented 3D sensor lip image based pronunciation recognition system.


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