Results 21 to 30 of about 10,061 (256)

Large sparse aperture telescope wavefront sensing and control via pretrained neural network with attention module [PDF]

Scientific Reports
The ability to detect pistons with high accuracy over a wide range is paramount to the co-phasing of sparse aperture optical systems. This paper proposes a global piston error modulation method for sparse aperture mirrors based on convolutional neural ...
Yuchen Li, Chao Qin, Qichang An, Zhenbang Xu   +3 more
doaj   +2 more sources

E-Nose for Piston Ring and Cylinder Block Condition Detection of Motorcycle Engine Based on MyRIO LabVIEW Programming [PDF]

JOIV: International Journal on Informatics Visualization
This study has created a system capable of identifying the condition of the piston ring and cylinder block of a 4-stroke motorcycle engine using petrol or similar through exhaust emissions.
- Andrizal, Yul Antonisfia, Nadia Alfitri, - Junaldi   +3 more
doaj   +3 more sources

High Precision Piston Error Sensing of Segmented Telescope Based on Frequency Domain Filtering

IEEE Photonics Journal
Piston error is the main component of the co-phase errors of segmented telescopes. In this paper, we innovatively performed frequency domain filtering and processing on the focal plane image of the segmented telescopes with mask added, and obtained the ...
Dequan Li, Dong Wang
doaj   +3 more sources

Control Strategies for Piston Trajectory in Ionic Compressors for Hydrogen Storage [PDF]

Applied Sciences, 2023
The ionic compressor is a new and prospective technology applied for hydrogen storage which adopts a hydraulic system in which the hydraulic drive unit is a solid piston in the compression cavity.
Yi Guo, Yuming Tang, Junhao Cao, Anna Diao, Xueyuan Peng   +4 more
doaj   +2 more sources

The Structure Research and Design for Beam Steering and Adjustment in Golay3 Sparse-Aperture Imaging System

Applied Sciences, 2022
In order to further explore the technical difficulties involved in orienting the sparse-aperture imaging system towards practical applications, this paper proposes an optical–mechanical structure design scheme and performance simulation, as well as ...
Junhong Qian, Xiaoyan Wu, Hewei Liu, Xiubao Hua, Ye Tao, Rongzhu Zhang   +5 more
doaj   +1 more source

Research on starting process and control strategy of opposed-piston free-piston engine generator _ Simulation and test results

Energy Reports, 2021
The operation process of free-piston engine generator (FPEG) can be divided into starting process and power generation process, and each of them faces severe challenges especially for the opposed-piston FPEG.
Limin Wu, Huihua Feng, Ziwei Zhang, Zhifeng Tang, Boru Jia, Xiaodong Yan   +5 more
doaj   +1 more source

Decoupled Object-Independent Image Features for Fine Phasing of Segmented Mirrors Using Deep Learning

Remote Sensing, 2022
A segmented primary mirror is very important for extra-large astronomical telescopes, in order to detect the phase error between segmented mirrors. Traditional iterative algorithms are hard to detect co−phasing aberrations in real time due to the long ...
Yirui Wang, Chunyue Zhang, Liang Guo, Shuyan Xu, Guohao Ju   +4 more
doaj   +1 more source

The LBTI Fizeau imager – II. Sensitivity of the PSF and the MTF to adaptive optics errors and to piston errors [PDF]

Monthly Notices of the Royal Astronomical Society, 2017
We show numerical simulations with monochromatic light in the visible for the LBTI Fizeau imager, including opto-dynamical aberrations due here to adaptive optics (AO) errors and to differential piston fluctuations, while other errors have been neglected.
Patru, F., Esposito, S., Puglisi, A., Riccardi, A., Pinna, E., Arcidiacono, C., Antichi, J., Mennesson, B., Defrère, D., Hinz, P., Hill, J.   +10 more
openaire   +3 more sources

Phasing piston error in segmented telescopes

Optics Express, 2016
To achieve a diffraction-limited imaging, the piston errors between the segments of the segmented primary mirror telescope should be reduced to λ/40 RMS. We propose a method to detect the piston error by analyzing the intensity distribution on the image plane according to the Fourier optics principle, which can capture segments with the piston errors ...
Junlun, Jiang, Weirui, Zhao
openaire   +2 more sources

Research on piston error sensing for segmented mirrors under atmospheric turbulence

Optics Express, 2023
Large aperture ground-based segmented telescopes typically use electrical edge sensors to detect co-phase errors. However, complex observing environments can lead to zero-point drift of the edge sensors, making it challenging to maintain the long-term co-phase of the segmented primary mirror using only edge sensors.
Bin Wang, Zhenyu Jin, Yichun Dai, DeHua Yang, FangYu Xu   +4 more
openaire   +2 more sources