• Title/Summary/Keyword: Visual observation

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Ecliptic Survey for Unknown Asteroids with DEEP-South

  • Lee, Mingyeong;JeongAhn, Youngmin;Yang, Hongu;Moon, Hong-Kyu;Choi, Young-Jun
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.63.2-63.2
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    • 2019
  • Eight hundred thousand asteroids in the solar system have been identified so far under extensive sky surveys. Kilometer to sub-km sized asteroids, however, are still waiting for discovery, and their size and orbital distribution will provide a better understanding of the collisional and dynamical evolution of the solar system. In order to study the number of asteroids which is detectable with 1.6 m telescope and their orbital distribution, we conducted a small observation campaign as a part of Deep Ecliptic Patrol of the Southern Sky (DEEP-South) project, which is an asteroid survey in the southern hemisphere with Korea Microlensing Telescope Network (KMTNet). We observed the ecliptic plane near opposition ($2^{\circ}{\times}2^{\circ}$ field of view centering on ${\alpha}=22h40m31s$, ${\delta}=-08^{\circ}22^{\prime}58^{{\prime}{\prime}}$) in August 2018, and identified 464 moving objects by visual inspection. As a result, 266 of 464 moving objects turn out to be previously unknown asteroids, and their signal to noise ratio is below two on numerous occasions. Most of the newly detected objects are main belt asteroids (MBAs), while three Hildas, one Jupiter trojan, and two Hungarias are also identified. In this meeting, we report the differences in the orbital distributions between the previously known asteroids and newly discovered ones using statistical methods. We also talk about the observational bias of this survey and suggest future works.

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Cross-Correlation of Oscillations in A Fragmented Sunspot

  • Lee, Kyeore;Chae, Jongchul
    • The Bulletin of The Korean Astronomical Society
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    • v.43 no.2
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    • pp.45.3-46
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    • 2018
  • Oscillations in a sunspot are easily detected through the Doppler velocity observation. Although the sunspot oscillations look erratic, the wavelet analysis show that they consist of successive wave packets which have strong power near three or five minutes. Previous studies found that 3-min oscillation at the chromosphere is a visual pattern of upward propagating acoustic waves along the magnetic field lines. Resent multi-height observations help this like vertical study, however, we also focus on horizontal facet to extend three dimensional understand of sunspot waves. So, we investigate a fragmented sunspot expected to have complex wave profiles according to the positions in the sunspot observed by the Fast Imaging Solar Spectrograph. We choose 4 points at different umbral cores as sampling positions to determine coherence of oscillations. The sets of cross-correlation with three and five minutes bandpass filters during a single wave packet reveal interesting results. Na I line show weak correlations with some lags, but Fe I and Ni I have strong correlations with no phase difference over the sunspots. It is more remarkable at Ni I line with 3-min bandpass that all sets of cross-correlation look like the autocorrelation. We can interpret this as sunspot oscillations occur spontaneously over a sunspot at photosphere but not at chromosphere. It implies a larger or deeper origin of 3-min sunspot oscillation.

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A Study on Sky Light Pollution based on Sky Glow in Jeju Island (스카이글루 분석을 통한 제주도 빛공해 실태조사)

  • Lee, So-Hyun;Lim, Hong-Soo
    • Journal of the Architectural Institute of Korea Structure & Construction
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    • v.34 no.4
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    • pp.83-91
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    • 2018
  • Artificial lighting contributes greatly to developing civilizations. It allows daytime activities to continue throughout the dark hours of the day and thus increasing work productivity as well as allowing people to enjoy nighttime activities. In addition, artificial lighting is used to beautify landscapes, architectural monuments, and thus highlighting the social-economic development of a given place. However, excessive and improper usage of artificial lighting can lead to light pollution. Light pollution is a serious issue that is detrimental to human health. It has been linked to a number of health conditions including sleep disorder, visual discomfort as well as cancer. The effects of light pollution extend throughout the entire ecosystem, affecting both plants and animals. Furthermore, sky-glow from light pollution hinders astronomical observation. The current paper presents a study conducted on lit environment of a nightscape. The quality of the sky was measured in 144 spots using Sky Quality Meter (SQM) devices. The measured spots were chosen on the basis of land use as well as distance from the Halla Mountain.

Evaluation of grout penetration in single rock fracture using electrical resistivity

  • Lee, Hangbok;Oh, Tae-Min;Lee, Jong-Won
    • Geomechanics and Engineering
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    • v.24 no.1
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    • pp.1-14
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    • 2021
  • In this study, a new approach using electrical resistivity measurement was proposed to detect grout penetration and to evaluate the grouting performance for such as waterproof efficiency in single rock fracture. For this purpose, an electrical resistivity monitoring system was designed to collect multi-channel data in real time. This was applied to a system for grout injection/penetration using a transparent fracture replica with various aperture sizes and water-cement mix ratio. The electrical resistivity was measured under various grout penetration conditions in real time, which results were directly compared to the visual observation images of grout penetration/distribution. Moreover, the grouting success status after the curing process was evaluated by measuring the electrical resistivity in relation to changes in frequency in fracture cells where grout injection and penetration were completed. Consequently, it was determined that the electrical resistivity monitoring system could be applied effectively to the detection of successful penetration of grouting into a target area and to actual field evaluation of the grouting performance and long-term stability of underground rock structures.

Factors Influencing Roadkill Hotspot in the Republic of Korea

  • Kim, Kyungmin;Yi, Yoonjung;Woo, Donggul;Park, Taejin;Song, Euigeun
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • v.2 no.4
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    • pp.274-278
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    • 2021
  • Road structures play an important role in collisions involving vehicles and wildlife. Our study aimed to determine the effect of various types of road structures on the risk associated with roadkill. We surveyed 50 previously identified roadkill hotspots, ranked from one to five according to roadkill density. We collected nine types of road structure data on each hotspot road section. Structures with similar characteristics were grouped together, resulting in five categories, namely, median barrier, high edge barrier, low edge barrier, speed, and visibility. We examined the existence of each road structure category at each hotspot rank. The cumulative link model showed that the absence of bottom blocked median barrier increased the roadkill hotspot rank. Our study concluded that a visual obstacle in the middle of roads by the median barrier decreases wildlife road crossing attempts and roadkill risk. We suggest that future roadkill mitigation plans should be established considering these characteristics.

Can Observational Gait Assessment Tools be used to Assess Independent Walking in Stroke Patients?

  • Ju, Sung-Kwang
    • Journal of the Korean Society of Physical Medicine
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    • v.17 no.1
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    • pp.11-20
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    • 2022
  • PURPOSE: A gait assessment is an important component of the rehabilitation process, and observational gait assessment (OGA) is used routinely in clinical settings. This study examined the association of OGA tools with the independent walking ability in stroke patients to determine a cutoff value of the OGA tool according to independence levels of stroke patient gait. METHODS: Two hundred ten hemiparetic stroke patients participated in the study. The independence of gait was identified using the Functional Ambulation Category (FAC) classifications. The walking ability was assessed using OGA tools (Rivermead Visual Gait Assessment [RVGA], Wisconsin Gait Scale [WGS], Tinetti Gait Scale [TGS], and Functional Gait Analysis [FGA]). RESULTS: Stepwise multiple regression analysis showed that among the OGA tools, the FGA correlated with the FAC. The FGA explained approximately 77% of the variance in FAC. In distinguishing the independence levels, the cutoff values were as follows: between FAC 1 and FAC 0 was .5 points; between FAC 2 and lower levels, 5.5; between FAC 3 and lower levels, 11.5; between FAC 4 and lower levels, 14.5; and between FAC 5 and lower levels, 18.5. Items 1, 2, 3, and 10 were identified as explaining most of the variance in the FGA in the stepwise multiple regression. CONCLUSION: The present study found that the FGA is an assessment tool related to the level of gait independence after stroke. Furthermore, the FGA total score can serve as an index of the increase in independence level after stroke.

Hydrocarbon seeps and mud volcanoes in the Caspian Sea characterized with use of the Envisat ASAR images

  • Zatyagalova, Victoria V.;Ivanov, Andrei Yu.
    • Proceedings of the KSRS Conference
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    • v.1
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    • pp.376-379
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    • 2006
  • A numerous oil slicks of natural origin were revealed in the southwest (SW) part of Caspian Sea by the synthetic aperture radar (SAR) images acquired by Envisat satellite in 2003-2004. On the basis of computer processing, visual analysis of SAR images and comparisons with bathymetry, geophysical and seismic data in geographic information system (GIS), a link between these slicks and unloading of liquid hydrocarbons in the SW Caspian is established. Oil slicks are basically concentrated above domes of local geological formations of the sedimentary cover. In total more than 90 seeps and mud volcanoes having a repeating regime and representing an active type were identified; they are distributed across the SW Azerbaijan and West Iranian sectors. Periodical occurrence of slicks can reflect alternation of mud volcanism pulses forced by intensive seismicity with the quiet periods. Seepage rate of oil in the SW part of the Caspian Sea according to SAR images is estimated to be up to 16,000 metric tons per year. The importance of unloading of oils on hydrochemistry and ecological conditions of the Caspian Sea is demonstrated. Conclusion is done that the Envisat SAR to be an excellent tool for studying oil seeps through observation oil slicks floating on the sea surface.

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Artificial Intelligence Plant Doctor: Plant Disease Diagnosis Using GPT4-vision

  • Yoeguang Hue;Jea Hyeoung Kim;Gang Lee;Byungheon Choi;Hyun Sim;Jongbum Jeon;Mun-Il Ahn;Yong Kyu Han;Ki-Tae Kim
    • Research in Plant Disease
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    • v.30 no.1
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    • pp.99-102
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    • 2024
  • Integrated pest management is essential for controlling plant diseases that reduce crop yields. Rapid diagnosis is crucial for effective management in the event of an outbreak to identify the cause and minimize damage. Diagnosis methods range from indirect visual observation, which can be subjective and inaccurate, to machine learning and deep learning predictions that may suffer from biased data. Direct molecular-based methods, while accurate, are complex and time-consuming. However, the development of large multimodal models, like GPT-4, combines image recognition with natural language processing for more accurate diagnostic information. This study introduces GPT-4-based system for diagnosing plant diseases utilizing a detailed knowledge base with 1,420 host plants, 2,462 pathogens, and 37,467 pesticide instances from the official plant disease and pesticide registries of Korea. The AI plant doctor offers interactive advice on diagnosis, control methods, and pesticide use for diseases in Korea and is accessible at https://pdoc.scnu.ac.kr/.

A Clinical Case Study of Idiopathic Bilateral Facial Nerve Palsy Treated with Korean and Western Medicine (특발성 양측성 안면신경마비의 한양방 복합치료 치험 1례)

  • Kyou Young Lee
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.37 no.3
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    • pp.49-62
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    • 2024
  • Objectives : The purpose of this study is to report on the good results achieved through Korean and western medicine treatment on patients with idiopathic bilateral facial nerve palsy. Methods : We treated a female patient with idiopathic bilateral facial nerve palsy by Korean medicine treatment such as herbal medicine, acupuncture, pharmacopuncture, cupping therapy, and taping therapy. The patient also received western medicine treatment. The treatment effect was evaluated by visual observation through photography, House-Brackmann scale, Yanagihara's scale, standardization of muscular paralysis, and clinical symptoms. Results : After the treatment, muscle movements and clinical symptoms improved, and all facial palsy evaluation indicators also showed improvement. In particular, the House-Brackmann-scale showed improvement from (3/4) to (1/2). Conclusions : This case study shows that Korean-western medicine combination treatment for idiopathic bilateral facial nerve palsy can be effective. We hope that case reports and clinical research will continue to be actively conducted in the future.

Filament, the Universal Nersery of Stars: Progress Report on TRAO Survery of Nearby Filamentary Filamentary Molecular Clouds

  • Kim, ShinYoung;Chung, Eun Jung;Lee, Chang Won;Myers, Philip C.;Caselli, Paola;Tafalla, Mario;Kim, Gwanjeong;Kim, Miryang;Soam, Archana;Gophinathan, Maheswar;Liu, Tie;Kim, Kyounghee;Kwon, Woojin;Kim, Jongsoo
    • The Bulletin of The Korean Astronomical Society
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    • v.42 no.2
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    • pp.79.2-79.2
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    • 2017
  • To dynamically and chemically understand how filaments, dense cores, and stars form under different environments, we are conducting a systematic mapping survey of nearby molecular clouds using the TRAO 14 m telescope with high ($N_2H^+$ 1-0, $HCO^+$ 1-0, SO 32-21, and $NH_2D$ v=1-0) and low ($^{13}CO$ 1-0, $C^{18}O$ 1-0) density tracers. The goals of this survey are to obtain the velocity distribution of low dense filaments and their dense cores for the study of their origin of the formation, to understand whether the dense cores form from any radial accretion or inward motions toward dense cores from their surrounding filaments, and to study the chemical differentiation of the filaments and the dense cores. Until the 2017A season, the real OTF observation time is ~760 hours. We have almost completed mapping observation with four molecular lines ($^{13}CO$ 1-0, $C^{18}O$ 1-0, $N_2H^+$ 1-0, and $HCO^+$ 1-0) on the six regions of molecular clouds (L1251 of Cepheus, Perseus West, Polaris South, BISTRO region of Serpens, California, and Orion B). The cube data for $^3CO$ and $C^{18}O$ lines were obtained for a total of 6 targets, 57 tiles, 676 maps, and $7.1deg^2$. And $N_2H^+$ and $HCO^+$ data were added for $2.2deg^2$ of dense regions. All OTF data were regridded to a cell size of 44 by 44 arcseconds. The $^{13}CO$ and $C^{18}O$ data show the RMS noise level of about (0.1-0.2) K and $N_2H^+$ and $HCO^+$ data show about (0.07-0.2) K at the velocity resolution of 0.06 km/s. Additional observations will be made on some regions that have not reached the noise level for analysis. To identify filaments, we are using and testing programs (DisPerSE, Dendrogram, FIVE) and visual inspection for 3D image of cube data. A basic analysis of the physical and chemical properties of each filament is underway.

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