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Measurement of Oil Thickness Using Snell’s Laser Refraction
Vasantha Kumar C(바산타쿠마르),Gyutae Park(박규태),Geumbi Park(박금비),Jinhwan Koh(고진환) 한국통신학회 2021 한국통신학회 학술대회논문집 Vol.2021 No.11
Concerns about oil spills are a major cause of marine contamination. If we can quantify the thickness of an oil slick, we will be able to better understand how oil spreads and behaves. Snell"s idea may be used to quantify refracted light beams in oil. A quantitative analysis of oil thickness was created using this method. A laser beam is focused towards the air/oil/water layer to conduct the test. When the refractive index of the medium changes, the beam rays refract. The location of a refracted laser beam ray is computed using Snell"s law, and the position is recorded by a camera module controlled remotely by a microcontroller. The X and Y coordinates of the beam ray location are determined by using Python OpenCV to analyze an image of the recorded beam position. The thickness of the oil is measured and evaluated after collecting the X and Y coordinates. The findings of the analysis were compared to the estimated thicknesses of the oil. The results of the tests show that the proposed method is accurate to within 1% error and can effectively quantify oil slick thicknesses on the water up to 11mm.
Oil Thickness Measurement Using Laser Refraction
Vasantha-Kumar(바산타쿠마르),Sungjae Park(박성재),Jinhwan Koh(고진환) 한국산학기술학회 2021 한국산학기술학회논문지 Vol.22 No.12
선박에서 유출된 석유 문제는 해양 오염의 심각한 원인이다. 기름의 두께를 추정하는 것은 전체의 유출량을 결정하는 데 매우 필요하다. 기름띠의 두께를 측정하는 것은 기름 확산에 대책을 강구할 수 있다는 것을 의미한다. 스넬의 법칙은 기름에서 굴절되는 광선을 계량화하는 데 사용될 수 있다. 이 접근법에 기초하여, 오일 두께에 대한 정량적 연구가 제안되었다. 테스트는 레이저 빔이 공기/기름/물 층을 통과하도록 하여 수행된다. 레이저 빔이 한 매체에서 다른 매체로 이동할 때, 빛은 매체의 굴절률 차이에 의해 굴절된다. 스넬의 법칙은 굴절된 레이저 빔의 위치를 계산하는 데 사용되며 마이크로컨트롤러에 의해 원격으로 제어되는 카메라 모듈에 의해 위치가 기록된다. 빔 위치의 캡처된 영상은 Python OpenCV를 사용하여 빔 광선 위치의 X 및 Y 좌표를 얻기 위해 영상처리된다. X 및 Y 좌표를 측정한 후 오일 두께를 계산한다. 실험 결과에 따르면 제안된 방법의 추정오차는 약 0.1% 이다. The problem of oil spills from ships is a serious cause of marine pollution. Therefore, estimating the thickness of oil is necessary to determine the overall runoff. Usually, measures can be taken against the spread of oil for the measurement of the thickness of the oil strip. Further, Snell"s law can be used to quantify the rays refracted in oil. This study proposed a quantitative study of oil thickness based on the above mentioned approach. In particular, the test is performed by passing a laser beam through an air/oil/water layer. When a laser beam travels from one medium to another, it is refracted by an amount proportional to the difference in refractive indices of the mediums. Subsequently, Snell"s law is used to calculate the position of the refracted laser beam, and the position is recorded by a camera module remotely controlled by a microcontroller. The captured image of the beam position is image processed to obtain the X and Y coordinates of the beam ray position using Python OpenCV. After measuring the X and Y coordinates, the oil thickness is calculated. However, the experimental results indicate that the error in the estimation of oil thickness by the proposed method is around 0.1%.
Super resolution-time delay estimation in multipath environment using matrix pencil method
Vasantha Kumar Chandrasegar(바산타 쿠마르 찬드라세가르),Minju Kim(김민주),Jinhwan Ko(고진환) 대한전자공학회 2023 대한전자공학회 학술대회 Vol.2023 No.6
The Matrix Pencil Method (MPM) is used in this research to recover the super-resolution time delay estimate (TDE) of signals in multi-path situations. Estimation errors are compared with existing Multiple Signal Classification (MUSIC) and cross-correlation methodologies to validate the new method. TDE generates measurements by crosscorrelation. Cross-correlation is based on a single model that considers the ideal environment. Simultaneously, when two or more signals are gradually inputted at intervals less than the time gap, the measurement precision begins to decline, necessitating superresolution for reliable time delay measurement. The suggested super-resolution MPM algorithm outperforms existing approaches in precisely recognizing and quantifying all components to their resolution limits and solving closely spaced frequencies.
Super Resolutional Time Delay Estimation in Multipath Environment Using Matrix Pencil Method
Chandrasegar Vasantha Kumar,Koh Jinhwan 대한전기학회 2022 Journal of Electrical Engineering & Technology Vol.17 No.1
This paper introduces techniques to restore super-resolution time delay estimation (TDE) of signals in multi-path environments using the Matrix Pencil Method (MPM). To verify the proposed algorithm, estimation errors are evaluated and compared with traditional Multiple Signal Classifi cation (MUSIC) and cross-correlation approaches. TDE uses cross-correlation to produce measurements. Cross-correlation is based on a single model that considers the ideal environment. At the same time, the measurement precision starts to deteriorate as two or more signals are progressively entered at times shorter than the time interval, requiring super-resolution for accurate time delay measurement. The results of the proposed super-resolution MPM algorithm provide better performance over conventional methods by accurately identifying and quantifying all components to their resolution limits and solving closely spaced frequencies
Prabhakaran Vasantha-Srinivasan,Muthiah Chellappandian,Muthiah Chellappandian,Sengottayan Senthil-Nathan,Athirstam Ponsankar,Annamalai Thanigaivel,Sengodan Karthi,Edward-Sam Edwin,Selvaraj Selin-Rani 한국응용곤충학회 2018 Journal of Asia-Pacific Entomology Vol.21 No.4
Fresh leaves of Piper betle Linn. (Piperales: Piperaceae) and Sphaeranthus indicus Linn. (Asterales: Asteraceae), commonly known as betel leaves and East Indian globe thistle, respectively, were harvested and steam distilled for the extraction of P. betle and S. indicus crude volatile oils (Pb-CVO and Si-CVO, respectively). LC 50 calculated on 3 rd instar larvae of dengue mosquito Aedes aegypti Linn. (Diptera: Culicidae) was 42.17 ppm for PbSi-CVO (i.e., herbal formulation based on the EOs of P. betle and S. indicus). The larval and pupal duration were significantly longer post-treatment with 100 ppm of PbSi-CVO, if compared to control. We observed that PbSi-CVO significantly altered the detoxifying enzymes GST and CYP450 compared to the expression of control. Sub-lethal concentrations of PbSi-CVO showed strong repellent properties against dengue mosquitoes, without adverse reactions on the volunteers experiencing the repellent assays. Lastly, the adulticidal activity of PbSi-CVO was studied. Overall, our study outlined that this herbal product represents a promising candidate for the development of botanical based adulticidal agents.
Dalit Christians Struggle for Justice in the Indian Sub-continent
Chilkuri Vasantha Rao 성공회대학교 신학연구소 2011 Madang: Journal of Contextual Theology Vol.16 No.-
In the wake of the contextual theologies world over, specific theologies with existential concerns have taken form. In the India-Subcontinent the women sliberation, ecological liberation; and with the specific influence of the black theology and the liberation theology, Dalit theology became a possibility in its particular socio-economic, political and religious context. Human tendencies seem to be universally common and oppression of the weak has been a ubiquitous dynamic showing different faces in different continents and countries. Dalit theology in India stands out with its undergirding principle of pathos, and hermeneutical principle of reading the scripture with the eyes of the poor1) and oppressed.