scholarly journals Micro-Motion Dynamics and Shape Parameters Estimation Based on an Infrared Signature Model of Spatial Targets

Electronics ◽  
2019 ◽  
Vol 8 (7) ◽  
pp. 755 ◽  
Author(s):  
Dongya Wu ◽  
Huanzhang Lu ◽  
Bendong Zhao ◽  
Junliang Liu ◽  
Ming Zhao
Keyword(s):  
Radiation Intensity ◽  
Infrared Radiation ◽  
Estimation Method ◽  
Optimization Techniques ◽  
Parameters Estimation ◽  
Geometrical Shape ◽  
Infrared Signature ◽  
Micro Motion ◽  
Periodic Fluctuations ◽  
Motion Dynamics

Infrared imaging is widely applied in the discrimination of spatial targets. Extracting distinguishable features from the infrared signature of spatial targets is an important premise for this task. When a target in outer space experiences micro-motion, it causes periodic fluctuations in the observed infrared radiation intensity signature. Periodic fluctuations can reflect some potential factors of the received data, such as structure, dynamics, etc., and provide possible ways to analyze the signature. The purpose of this paper is to estimate the micro-motion dynamics and geometry parameters from the observed infrared radiation intensity signature. To this end, we have studied the signal model of the infrared radiation intensity signature, conducted the geometry and micro-motion models of the target, and we proposed a joint parameter estimation method based on optimization techniques. After analyzing the estimation results, we testified that the parameters of micro-motion and geometrical shape of the spatial target can be effectively estimated by our estimation method.

Ground experimental simulation method of infrared radiation of high altitude aircraft’s surface

2018 ◽  
Vol 233 (8) ◽  
pp. 2980-2991
Author(s):  
Hao Wang ◽  
Jian Liu ◽  
Honghu Ji
Keyword(s):  
High Altitude ◽  
Radiation Intensity ◽  
Infrared Radiation ◽  
Simulation Method ◽  
Experimental Simulation ◽  
Scale Model ◽  
Surface Model ◽  
Wavelength Band ◽  
Temperature Range ◽  
Infrared Signature

It is difficult and costly to accurately measure the spectral and spatial distributions of the infrared radiation signature of a high altitude aircraft’s surface at relatively low temperatures. To reduce the experimental cost, simulated experimental measurement on the ground is usually made to measure its infrared signature. However, there are three main difficulties in the ground measurement: (1) it is difficult to simulate the temperature at high altitude which is much lower than the temperature near the ground; (2) it is difficult to accurately measure the infrared signature of a low temperature surface on the ground; and (3) it is difficult to measure the infrared signature of a prototype aircraft surface. To solve these problems, a ground experimental simulation method to obtain the infrared signature of a high altitude aircraft’s surface is developed, which makes it possible to use a scale model (scale factor M) at relatively higher temperature ( n times the temperature of the aircraft’s surface) to experimentally simulate the infrared signature of the actual aircraft’s surface. The results show that the integrated radiation intensity in the wavelength band between λ1 and λ2 of an original flying aircraft’s surface at a temperature range from T1 to T2 is equal to [Formula: see text] times the integrated radiation intensity in the wavelength band between λ1/ n and λ2/ n of the scale test surface model on the ground at a temperature range from nT1 to nT2.

scholarly journals Experimental Evaluation of PSO Based Transfer Learning Method for Meteorological Visibility Estimation

Atmosphere ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 828
Author(s):  
Wai Lun Lo ◽  
Henry Shu Hung Chung ◽  
Hong Fu
Keyword(s):  
Transfer Learning ◽  
Experimental Evaluation ◽  
Estimation Method ◽  
Image Features ◽  
Parameters Estimation ◽  
Image Feature ◽  
Support Vector ◽  
Learning Method ◽  
Feature Vectors ◽  
Visibility Estimation

Estimation of Meteorological visibility from image characteristics is a challenging problem in the research of meteorological parameters estimation. Meteorological visibility can be used to indicate the weather transparency and this indicator is important for transport safety. This paper summarizes the outcomes of the experimental evaluation of a Particle Swarm Optimization (PSO) based transfer learning method for meteorological visibility estimation method. This paper proposes a modified approach of the transfer learning method for visibility estimation by using PSO feature selection. Image data are collected at fixed location with fixed viewing angle. The database images were gone through a pre-processing step of gray-averaging so as to provide information of static landmark objects for automatic extraction of effective regions from images. Effective regions are then extracted from image database and the image features are then extracted from the Neural Network. Subset of Image features are selected based on the Particle Swarming Optimization (PSO) methods to obtain the image feature vectors for each effective sub-region. The image feature vectors are then used to estimate the visibilities of the images by using the Multiple Support Vector Regression (SVR) models. Experimental results show that the proposed method can give an accuracy more than 90% for visibility estimation and the proposed method is effective and robust.

Numerical evaluation of the exhaust-direction effects on plume flow and helicopter infrared radiation under hover and cruise statuses

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Zongyao Yang ◽  
Yong Shan ◽  
Jingzhou Zhang
Keyword(s):  
Radiation Intensity ◽  
Infrared Radiation ◽  
Design Methodology ◽  
Main Rotor ◽  
Content Type ◽  
Exhaust Plume ◽  
Ir Signature ◽  
Plume Flow ◽  
The Impact ◽  
Rotational Direction

Purpose This study aims to investigate the effects of exhaust direction on exhaust plume and helicopter infrared radiation in hover and cruise status. Design/methodology/approach Four exhaust modes are concerned, and the external flow field and fuselage temperature field are calculated by numerical simulation. The infrared radiation intensity distributions of the four models in hovering and cruising states are computed by the ray-tracing method. Findings Under the hover status, the exhaust plume is deflected to flow downward after it exhausts from the nozzle exit, upon the impact of the main-rotor downwash. Besides, the exhaust plume shows a “swirling” movement following the main-rotor rotational direction. The forward-flight flow helps prevent the hot exhaust plume from a collision with the helicopter fuselage generally for the cruise status. In general, the oblique-upward exhaust mode provides moderate infrared radiation intensities in all of the viewing directions, either under the hover or the cruise status. Compared with the hover status, the infrared radiation intensity distribution alters somewhat in cruise. Originality/value Illustrating the influences of exhaust direction on plume flow and helicopter infrared radiation and the differences of helicopter infrared radiation under hover and cruise statuses are identified. Finally, an appropriate exhaust mode is proposed to provide a better IR signature distribution.

scholarly journals Analysis of Infrared Radiation Intensity by Water-Mist Spraying in Ship Exhaust System

2021 ◽  
Vol 2112 (1) ◽  
pp. 012019
Author(s):  
Zhongke Sun ◽  
Zhen Wang ◽  
Zhongwei Chen ◽  
Zhihua Liu ◽  
Mo Liu ◽  
...  
Keyword(s):  
Radiation Intensity ◽  
Infrared Radiation ◽  
Exhaust System ◽  
Water Mist ◽  
Mist Cooling

Abstract The infrared radiation intensity in 3~5μm of conventional ship exhaust system are so severe [1] that can be easily captured by detector. Therefore, it’s necessary to take measure like spraying water mist to decrease temperature of exhaust system in order to decrease infrared radiation intensity. In this paper, the calculation of infrared radiation intensity of conventional ship exhaust system with water-mist spraying will be given. The results show that the average and maximum infrared radiation intensity of the exhaust system can be reduced by 90.3% and 95.7% after water mist cooling.

Study of Tunnel Water Detection through Infrared Acquisition Technology Based on 3D Trend Analysis

2013 ◽  
Vol 838-841 ◽  
pp. 1370-1380
Author(s):  
Shu Hao Zhang ◽  
Ya Wei Wang
Keyword(s):  
Trend Analysis ◽  
Radiation Field ◽  
Radiation Intensity ◽  
Infrared Radiation ◽  
Tunnel Construction ◽  
Water Detection ◽  
Visualization Software ◽  
Comparison And Analysis

The study discusses a revised method of water detection through infrared acquisition technology. In the case of Xianghe tunnel construction, the authors built 3D infrared radiation field functions through 3D trend analysis. The separately calculated radiation intensity trend values and outliers were processed by the visualization software, Voxler, and transformed into 3D distribution graphs for further comparison and analysis. The result indicates that the technique and method applied in this article successfully eliminate the random interference and realize the detection of aquifer.

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