scholarly journals Thermal Imager Range: Predictions, Expectations, and Reality

Sensors ◽  
2019 ◽  
Vol 19 (15) ◽  
pp. 3313 ◽  
Author(s):  
Dragana Perić ◽  
Branko Livada ◽  
Miroslav Perić ◽  
Saša Vujić
Keyword(s):  
Long Range ◽  
Imaging System ◽  
Weather Conditions ◽  
Theoretical Models ◽  
Field Conditions ◽  
Design Parameters ◽  
Surveillance Systems ◽  
Thermal Imager ◽  
Adverse Weather ◽  
Thermal Imagers

Imaging system range defines the maximal distance at which a selected object can be seen and perceived following surveillance task perception criteria. Thermal imagers play a key role in long-range surveillance systems due to the ability to form images during the day or night and in adverse weather conditions. The thermal imager range depends on imager design parameters, scene and transmission path properties. Imager range prediction is supported by theoretical models that provide the ability to check range performance, compare range performances for different systems, extend range prediction in field conditions, and support laboratory measurements related to range. A condensed review of the theoretical model’s genesis and capabilities is presented. We applied model-based performance calculation for several thermal imagers used in our long-range surveillance systems and compared the results with laboratory performance measurement results with the intention of providing the range prediction in selected field conditions. The key objective of the paper is to provide users with reliable data regarding expectations during a field mission.

Research on long-range laser active imaging system applied in adverse weather conditions

2013 ◽  
Author(s):  
Zhi-gang Gai ◽  
Meng-de Liu ◽  
Li Yang ◽  
V. V. Kabanov ◽  
Lei Shi ◽  
...  
Keyword(s):  
Long Range ◽  
Imaging System ◽  
Weather Conditions ◽  
Adverse Weather Conditions ◽  
Adverse Weather ◽  
Active Imaging

scholarly journals TECHNICAL MEANS OF AIRINTELLIGENCE TO ENSURE THE PHYSICAL SECURITY OF INFORMATION ACTIVITIES

2021 ◽  
Vol 12 (4) ◽  
pp. 143-150
Author(s):  
Artem Platonenko ◽  
Volodymyr Sokolov ◽  
Pavlo Skladannyi ◽  
Heorhii Oleksiienko
Keyword(s):  
Thermal Imaging ◽  
Critical Infrastructure ◽  
Weather Conditions ◽  
Unmanned Vehicles ◽  
License Plate ◽  
Thermal Imager ◽  
Camera Model ◽  
Thermal Imagers ◽  
Private And Public

This article is devoted to highlighting the real practical capabilities of UAV thermal imaging cameras, which allow you to effectively and safely identify potentially dangerous objects that may threaten the object of information activities, or the safety of citizens or critical infrastructure of Ukraine. Based on many years of flight experience and training of specialists for private and public institutions, it was decided to compare the quality characteristics and capabilities of detection, recognition and identification of objects using modern unmanned vehicles. To ensure public safety and control of the territory, there are models with multiple optical zoom, which from a distance of 500 m allow to recognize the license plate of the car, or versions with thermal imager, which in night can help see the car, the temperature difference against other cars, and the fact that a person comes out of it. Test flights were performed at altitudes from 15 to 100 m, in the open, without the presence of bushes, trees or obstacles. Depending on the camera model and weather conditions, the figures obtained may differ significantly. The main advantages and differences in the quality of thermal imaging cameras for UAVs are described. The quality of the obtained image is demonstrated on real examples and under the same conditions. A number of requirements have been developed for shooting a quadcopter with thermal imagers of objects such as a car and a person from different heights, according to Johnson's criteria, and a work plan has been developed for further research to prepare and provide effective recommendations for pilots using this technique territories of objects of information activity and during performance of service in air reconnaissance units of law enforcement agencies of Ukraine.

scholarly journals Gyroscope-Based Video Stabilization for Electro-Optical Long-Range Surveillance Systems

Sensors ◽  
2021 ◽  
Vol 21 (18) ◽  
pp. 6219
Author(s):  
Petar D. Milanović ◽  
Ilija V. Popadić ◽  
Branko D. Kovačević
Keyword(s):  
Long Range ◽  
Weather Conditions ◽  
Optical Systems ◽  
Video Stabilization ◽  
Electromagnetic Spectrum ◽  
Surveillance Systems ◽  
Feature Based ◽  
Gyro Bias ◽  
Bias Instability ◽  
Estimation Quality

Video stabilization is essential for long-range electro-optical systems, especially in situations when the field of view is narrow, since the system shake may produce highly deteriorating effects. It is important that the stabilization works for different camera types, i.e., different parts of the electromagnetic spectrum independently of the weather conditions and any form of image distortion. In this paper, we propose a method for real-time video stabilization that uses only gyroscope measurements, analyze its performance, and implement and validate it on a real-world professional electro-optical system developed at Vlatacom Institute. Camera movements are modeled with 3D rotations obtained by integration of MEMS gyroscope measurements. The 3D orientation estimation quality depends on the gyroscope characteristics; we provide a detailed discussion on the criteria for gyroscope selection in terms of the sensitivity, measurement noise, and drift stability. Furthermore, we propose a method for improving the unwanted motion estimation quality using interpolation in the quaternion domain. We also propose practical solutions for eliminating disturbances originating from gyro bias instability and noise. In order to evaluate the quality of our solution, we compared the performance of our implementation with two feature-based digital stabilization methods. The general advantage of the proposed methods is its drastically lower computational complexity; hence, it can be implemented for a low price independent of the used electro-optical sensor system.

scholarly journals Sustainability of Vibration Mitigation Methods Using Meta-Materials/Structures along Railway Corridors Exposed to Adverse Weather Conditions

2020 ◽  
Vol 12 (24) ◽  
pp. 10236
Author(s):  
Sakdirat Kaewunruen ◽  
Zhangjun Qin
Keyword(s):  
Carbon Emissions ◽  
Low Frequency ◽  
Weather Conditions ◽  
Propagation Path ◽  
Transport Systems ◽  
Design Parameters ◽  
Transmission Path ◽  
Adverse Weather Conditions ◽  
Adverse Weather ◽  
Mitigation Methods

Noises and vibrations caused by operating transport systems can seriously affect people’s health and environmental ecosystems. Railway-induced vibrations in urban settings can cause disturbances and damages to surrounding buildings, infrastructures and residents. Over many decades, a number of mitigation methods have been proposed to attenuate vibrations at the source, in the transmission path, or at the receiver. In fact, low-frequency or ground-borne vibration is turned out to be more difficult to be mitigated at source, whilst some attenuation measures in propagation path can be applicable. To broaden the mitigating range at the low-frequency band, the applications of meta-materials/structures have been established. In railway systems, periodic structures or resonators can be installed near the protected buildings to isolate the vibrations. Despite a large number of proposed attenuation methods, the sustainability of those methods has not been determined. Based on rational engineering assumptions, the discounted cash flows in construction and maintenance processes are analysed in this study to evaluate lifecycle costs and the quantity of materials and fuels, as well as the amount of carbon emissions. This study is the world’s first to identify the efficacy and sustainability of some transmission path attenuation methods in both normal and adverse weather conditions. It reveals that geofoam trenches and wave impeding blocks are the most suitable methods. Although metamaterial applications can significantly mitigate a wider range of lower frequency vibrations, the total cost and carbon emissions are relatively high. It is necessary to significantly modify design parameters in order to enable low-cost and low-carbon meta-materials/structures in reality.

scholarly journals Precipitation Modeling for Extreme Weather Based on Sparse Hybrid Machine Learning and Markov Chain Random Field in a Multi-Scale Subspace

Water ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1241
Author(s):  
Ming-Hsi Lee ◽  
Yenming J. Chen
Keyword(s):  
Machine Learning ◽  
Markov Chain ◽  
Random Field ◽  
Long Range ◽  
Weather Conditions ◽  
Extreme Weather ◽  
Prediction Algorithm ◽  
Learning Method ◽  
Multi Scale ◽  
Hybrid Machine

This paper proposes to apply a Markov chain random field conditioning method with a hybrid machine learning method to provide long-range precipitation predictions under increasingly extreme weather conditions. Existing precipitation models are limited in time-span, and long-range simulations cannot predict rainfall distribution for a specific year. This paper proposes a hybrid (ensemble) learning method to perform forecasting on a multi-scaled, conditioned functional time series over a sparse l1 space. Therefore, on the basis of this method, a long-range prediction algorithm is developed for applications, such as agriculture or construction works. Our findings show that the conditioning method and multi-scale decomposition in the parse space l1 are proved useful in resisting statistical variation due to increasingly extreme weather conditions. Because the predictions are year-specific, we verify our prediction accuracy for the year we are interested in, but not for other years.

scholarly journals Ship Handling in Unprotected Waters: A Review of New Technologies in Escort Tugs to Improve Safety

2021 ◽  
Vol 2 (1) ◽  
pp. 46-62
Author(s):  
Santiago Iglesias-Baniela ◽  
Juan Vinagre-Ríos ◽  
José M. Pérez-Canosa
Keyword(s):  
High Performance ◽  
New Technologies ◽  
Weather Conditions ◽  
Hull Form ◽  
Best Available Technologies ◽  
Adverse Weather Conditions ◽  
Adverse Weather ◽  
New Type ◽  
Technological Challenge ◽  
And Performance

It is a well-known fact that the 1989 Exxon Valdez disaster caused the escort towing of laden tankers in many coastal areas of the world to become compulsory. In order to implement a new type of escort towing, specially designed to be employed in very adverse weather conditions, considerable changes in the hull form of escort tugs had to be made to improve their stability and performance. Since traditional winch and ropes technologies were only effective in calm waters, tugs had to be fitted with new devices. These improvements allowed the remodeled tugs to counterbalance the strong forces generated by the maneuvers in open waters. The aim of this paper is to perform a comprehensive literature review of the new high-performance automatic dynamic winches. Furthermore, a thorough analysis of the best available technologies regarding towline, essential to properly exploit the new winches, will be carried out. Through this review, the way in which the escort towing industry has faced this technological challenge is shown.

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