Reducing the Optical Noise of Machine Vision Optical Scanners for Landslide Monitoring

Author(s):  
Jesús Elias Miranda-Vega ◽  
Javier Rivera-Castillo ◽  
Moisés Rivas-López ◽  
Wendy Flores-Fuentes ◽  
Oleg Sergiyenko ◽  
...  

An application of landslide monitoring using optical scanner as vision system is presented. The method involves finding the position of non-coherent light sources located at strategic points susceptible to landslides. The position of the light source is monitored by measuring its coordinates using a scanner based on a 45° sloping surface cylindrical mirror. This chapter shows experiments of position light source monitoring in laboratory environment. This work also provides improvements for the optical scanner by using digital filter to smooth the opto-electronic signal captured from a real environment. The results of these experiments were satisfactory by implementing the moving average filter and median filter.

Author(s):  
Javier Rivera Castillo ◽  
Moises Rivas-Lopez ◽  
Wendy Flores-Fuentes ◽  
Oleg Sergiyenko ◽  
Julio Cesar Rodríguez-Quiñonez ◽  
...  

An application of landslide monitoring using optical scanner as vision system is presented. The method involves finding the position of non-coherent light sources located at strategic points susceptible to landslides. The position of the light source is monitored by measuring its coordinates using a scanner based on a 45° sloping surface cylindrical mirror. This chapter also provides a background about the concept of landslides and technologies for monitoring. finally, the results of experiments of position light source monitoring in laboratory environment using the proposed method are presented.


Minerals ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 38
Author(s):  
Zitong Zhao ◽  
Ying Guo

The CIECAM16 colour appearance model is currently a model with high prediction accuracy. It can solve the problem of predicting the influence of different observation conditions on the colour of gemstones. In this study, a computer vision system (CVS) was used to measure the colour of 59 bluish-green serpentinite samples, and the tristimulus values were input into the CIECAM16 forward model to calculate the colour appearance parameters of serpentinite under different surrounds, illuminances, and light sources. It was found that the darkening of the surround causes the lightness and brightness to increase. Pearson’s r of brightness and colourfulness with illuminance is 0.885 and 0.332, respectively, which predicts the Stevens and Hunt effects. When the light source changes from D65 to A, the calculated hue angle shifts to the complementary area of the A light source, which is contrary to the CVS measurement result. The D65 light source is more suitable for the colour presentation and classification of bluish-green serpentinite.


2019 ◽  
pp. 101-107
Author(s):  
Sergei A. Stakharny

This article is a review of the new light source – organic LEDs having prospects of application in general and special lighting systems. The article describes physical principles of operation of organic LEDs, their advantages and principal differences from conventional non-organic LEDs and other light sources. Also the article devoted to contemporary achievements and prospects of development of this field in the spheres of both general and museum lighting as well as other spheres where properties of organic LEDs as high-quality light sources may be extremely useful.


2021 ◽  
Vol 11 (9) ◽  
pp. 4035
Author(s):  
Jinsheon Kim ◽  
Jeungmo Kang ◽  
Woojin Jang

In the case of light-emitting diode (LED) seaport luminaires, they should be designed in consideration of glare, average illuminance, and overall uniformity. Although it is possible to implement light distribution through auxiliary devices such as reflectors, it means increasing the weight and size of the luminaire, which reduces the feasibility. Considering the special environment of seaport luminaires, which are installed at a height of 30 m or more, it is necessary to reduce the weight of the device, facilitate replacement, and secure a light source with a long life. In this paper, an optimized lens design was investigated to provide uniform light distribution to meet the requirement in the seaport lighting application. Four types of lens were designed and fabricated to verify the uniform light distribution requirement for the seaport lighting application. Using numerical analysis, we optimized the lens that provides the required minimum overall uniformity for the seaport lighting application. A theoretical analysis for the heatsink structure and shape were conducted to reduce the heat from the high-power LED light sources up to 250 W. As a result of these analyses on the heat dissipation characteristics of the high-power LED light source used in the LED seaport luminaire, the heatsink with hexagonal-shape fins shows the best heat dissipation effect. Finally, a prototype LED seaport luminaire with an optimized lens and heat sink was fabricated and tested in a real seaport environment. The light distribution characteristics of this prototype LED seaport luminaire were compared with a commercial high-pressure sodium luminaire and metal halide luminaire.


Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 343
Author(s):  
Kim Bjerge ◽  
Jakob Bonde Nielsen ◽  
Martin Videbæk Sepstrup ◽  
Flemming Helsing-Nielsen ◽  
Toke Thomas Høye

Insect monitoring methods are typically very time-consuming and involve substantial investment in species identification following manual trapping in the field. Insect traps are often only serviced weekly, resulting in low temporal resolution of the monitoring data, which hampers the ecological interpretation. This paper presents a portable computer vision system capable of attracting and detecting live insects. More specifically, the paper proposes detection and classification of species by recording images of live individuals attracted to a light trap. An Automated Moth Trap (AMT) with multiple light sources and a camera was designed to attract and monitor live insects during twilight and night hours. A computer vision algorithm referred to as Moth Classification and Counting (MCC), based on deep learning analysis of the captured images, tracked and counted the number of insects and identified moth species. Observations over 48 nights resulted in the capture of more than 250,000 images with an average of 5675 images per night. A customized convolutional neural network was trained on 2000 labeled images of live moths represented by eight different classes, achieving a high validation F1-score of 0.93. The algorithm measured an average classification and tracking F1-score of 0.71 and a tracking detection rate of 0.79. Overall, the proposed computer vision system and algorithm showed promising results as a low-cost solution for non-destructive and automatic monitoring of moths.


2010 ◽  
Vol 2010 ◽  
pp. 1-9 ◽  
Author(s):  
Andrew Chalmers ◽  
Snjezana Soltic

This paper is concerned with designing light source spectra for optimum luminous efficacy and colour rendering. We demonstrate that it is possible to design light sources that can provide both good colour rendering and high luminous efficacy by combining the outputs of a number of narrowband spectral constituents. Also, the achievable results depend on the numbers and wavelengths of the different spectral bands utilized in the mixture. Practical realization of these concepts has been demonstrated in this pilot study which combines a number of simulations with tests using real LEDs (light emitting diodes). Such sources are capable of providing highly efficient lighting systems with good energy conservation potential. Further research is underway to investigate the practicalities of our proposals in relation to large-scale light source production.


2021 ◽  
Author(s):  
Wen-Ting Li ◽  
Le Wang ◽  
Wei Li ◽  
Sheng-Mei Zhao

Abstract The transmission loss of photons during quantum key distribution(QKD) process leads to the linear key rate bound for practical QKD systems without quantum repeaters. Phase matching quantum key distribution (PM-QKD) protocol, an novel QKD protocol, can overcome the constraint with a measurement-device-independent structure, while it still requires the light source to be ideal. This assumption is not guaranteed in practice, leading to practical secure issues. In this paper, we propose a modified PM-QKD protocol with a light source monitoring, named PM-QKD-LSM protocol, which can guarantee the security of the system under the non-ideal source condition. The results show that our proposed protocol performs almost the same as the ideal PM-QKD protocol even considering the imperfect factors in practical systems. PM-QKD-LSM protocol has a better performance with source fluctuation, and it is robust in symmetric or asymmetric cases.


Author(s):  
Д.А. Смирнов ◽  
В.Г. Бондарев ◽  
А.В. Николенко

Проведен краткий анализ как отечественных, так и зарубежных систем межсамолетной навигации. В ходе анализа были отражены недостатки систем межсамолетной навигации и представлен актуальный подход повышения точности системы навигации за счет применения системы технического зрения. Для определения местоположения ведущего самолета предлагается рассмотреть в качестве измерительного комплекса систему технического зрения, которая способна решать большой круг задач на различных этапах, в частности, и полет строем. Систему технического зрения предлагается установить на ведомом самолете с целью измерения всех параметров, необходимых для формирования автоматического управления полетом летательного аппарата. Обработка изображений ведущего самолета выполняется с целью определения координат трех идентичных точек на фоточувствительных матрицах. Причем в качестве этих точек выбираются оптически контрастные элементы конструкции летательного аппарата, например окончания крыла, хвостового оперения и т.д. Для упрощения процедуры обработки изображений возможно использование полупроводниковых источников света в инфракрасном диапазоне (например, с длиной волны λ = 1,54 мкм), что позволяет работать даже в сложных метеоусловиях. Такой подход может быть использован при автоматизации полета строем более чем двух летательных аппаратов, при этом необходимо только оборудовать системой технического зрения все ведомые самолеты группы The article provides a brief analysis of both domestic and foreign inter-aircraft navigation systems. In the course of the analysis, we found the shortcomings of inter-aircraft navigation systems and presented an up-to-date approach to improving the accuracy of the navigation system through the use of a technical vision system. To determine the location of the leading aircraft, we proposed to consider a technical vision system as a measuring complex, which is able to solve a large range of tasks at various stages, in particular, flight in formation. We proposed to install the technical vision system on the slave aircraft in order to measure all the parameters necessary for the formation of automatic flight control of the aircraft. We performed an image processing of the leading aircraft to determine the coordinates of three identical points on photosensitive matrices. Moreover, we selected optically contrasting elements of the aircraft structure as these points, for example, the end of the wing, tail, etc. To simplify the image processing procedure, it is possible to use semiconductor light sources in the infrared range (for example, with a wavelength of λ = 1.54 microns), which allows us to work even in difficult weather conditions. This approach can be used when automating a flight in formation of more than two aircraft, while it is only necessary to equip all the guided aircraft of the group with a technical vision system


Author(s):  
Wenxuan Jia ◽  
Yuen-Shan Leung ◽  
Huachao Mao ◽  
Han Xu ◽  
Chi Zhou ◽  
...  

Abstract Microscale surface structures are commonly found on macroscale bodies of natural creatures for their unique functions. However, it is difficult to fabricate such multi-scale geometry with conventional stereolithography processes that rely on either laser or digital micromirror device (DMD). More specifically, the DMD-based mask projection method displays the image of a cross-section of the part on the resin to fabricate the entire layer efficiently; however, its display resolution is limited by the building area. In comparison, the laser-based vector scanning method builds smooth features using a focused laser beam with desired beam-width resolution; however, it has less throughput for its sequential nature. In this paper, we studied the hybrid-light-source stereolithography process that integrates both optical light sources to facilitate the fabrication of macro-objects with microscale surface structures (called micro-textures in the paper). The hardware system uses a novel calibration approach that ensures pixel-level dimensional accuracy across the two light sources. The software system enables designing the distribution and density of specific microscale textures on a macro-object by generating projection images and laser toolpaths for the two integrated light sources. Several test cases were fabricated to demonstrate the capability of the developed process. A large fabrication area (76.8 mm × 80.0 mm) with 50 μm micro-features can be achieved with a high throughput.


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