• Title/Summary/Keyword: Physical Cause

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A Study on Possibility of Improvement of MIR Brightness Temperature Bias Error of KOMPSAT-3A Using GEOKOMPSAT-2A (천리안2A호를 이용한 다목적실용위성3A호 중적외선 밝기 온도 편향오차 개선 가능성 연구)

  • Kim, HeeSeob
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.48 no.12
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    • pp.977-985
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    • 2020
  • KOMPSAT-3A launched in 2015 provides Middle InfraRed(MIR) images with 3.3~5.2㎛. Though the satellite provide high resolution images for estimating bright temperature of ground objects, it is different from existing satellites developed for natural science purposes. An atmospheric compensation process is essential in order to estimate the surface brightness temperature from a single channel MIR image of KOMPSAT-3A. However, even after the atmospheric compensation process, there is a brightness temperature error due to various factors. In this paper, we analyzed the cause of the brightness temperature estimation error by tracking signal flow from camera physical characteristics to image processing. Also, we study on possibility of improvement of MIR brightness temperature bias error of KOMPSAT-3A using GEOKOMPSAT-2A. After bias compensation of a real nighttime image with a large bias error, it was confirmed that the surface brightness temperature of KOMPSAT-3A and GEOKOMPSAT-2A have correlation. We expect that the GEOKOMPSAT-2A images will be helpful to improve MIR brightness temperature bias error of KOMPSAT-3A.

A Study on Rust Cleaning of Various Industrial Equipment Using Cosmetic and Food Materials (화장품과 식품 재료를 이용한 각종 산업장비 녹(rust) 세정에 관한 연구)

  • Yeom, Seok-Jae;Jung, Sundo;Oh, Eunha
    • Journal of the Korean Applied Science and Technology
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    • v.38 no.1
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    • pp.19-28
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    • 2021
  • Corrosion is the degradation of metals by reaction with the environment. It is difficult to completely remove. Corrosion proceeds rapidly after the protective barrier is destroyed, and several reactions occur that alter the composition and properties of the metal surface and local environments, such as diffusion of metal cations into the matrix, the formation of oxides, and local pH changes. The study of corrosion of steel and iron is of theoretical and practical interest and is receiving considerable attention. Acid solutions, which are widely used in industrial pickling, acid descaling, cleaning and acidification of oil wells, require the use of corrosion inhibitors to suppress corrosion attacks on metallic materials. Physical removal of rust requires expensive special equipment, and chemical removal of it can cause corrosion or shorten the life of the metal. In this study, an eco-friendly rust cleaner was developed using cosmetics and food materials by applying the concept of perm reducing agent and chelate, and applied to remove rust from industrial and hot water pipes and various industrial devices. As a result, it was found that rust cleaners remove rust more effectively and safely compared to conventional treatment methods. At the same time, the rust removal efficiency was 1.75 to 2.5 times better for industrial piping and 1.56 to 2.2 times better for boiler hot water than conventional methods.

A Study on the Utilization of Empty Houses in Rural Village - Focused on the Hacheon Village in Gimje City - (농촌마을 빈집의 활용방안에 관한 연구 - 김제 하천마을 중심으로 -)

  • Shim, Yu-Hyeon;Shin, Byeong-Uk;Nam, Hae-Kyeong
    • Journal of the Korean Institute of Rural Architecture
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    • v.24 no.1
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    • pp.27-36
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    • 2022
  • Currently the population of rural areas in Korea continue to decline due to low birth rate, aging population, and migration. This phenomenon is accelerated over time. And as a result, there are some declining phenomenon in rural society. And it is same in the residential and basic living conditions of rural villages. The increase ratio of empty houses exacerbates the rural landscape, acts as a cause of crime and bring out various social and economic problems such as worsening settlement conditions and local slums. The study is carried out to prevent this phenomenon by investigating the architectural contents of empty houses in the village, surveyed residents and owners and finally analyzed and synthesized to make a plan to utilize empty houses in the village. This study was conducted from June to December 2021. The conclusions are followings: 1. The empty houses in Korea were 1,511 million in 2020, 8.2% of the total number of houses, whereas those in Jeollabuk-do were 95,412, 12.9% of those of houses, and those in Gimje-city, the subject of this study, were 5,944. It is up to 15.8%. In particular, empty houses in Hacheon village, the site of this study, accounted for the highest ratio, with 25% of the total number of houses. 2. To understand the utilization and improvement of empty houses, surveys and interviews were conducted to residents and owners of Hacheon village in Gimje, and most of the residents submit proposals that empty houses were not desirable in terms of village landscape and safety. The owners don't have intentions of selling or leasing them. They want to remodel them and rent for a specific period. 3. As the physical condition of the empty houses(9empty houses) 6 empty houses of them are good. 4 of them are in poor condition. 4. By synthesizing these contents, nine empty houses in Hacheon village will be remodeled as the space for those of rural start-up young people, smart farm area, community space and rental housings for rural returnees.

A Study on the Comedic Acting Methods in the Play - Focusing on Character of Kim Seo-Young - (연극 <코트>에 나타난 희극적 연기 방법 연구 - 김서영 역을 중심으로 -)

  • Kim, Seok
    • Journal of Korea Entertainment Industry Association
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    • v.15 no.4
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    • pp.89-100
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    • 2021
  • Comedy has been popular since ancient Greece. In order to visualize comedy more effectively, the actor's acting acts as an important factor. Then active discussion is needed on how actors can actually shape their comedic performance. I would like to approach comedic acting methods, focusing on the character of Kim Seo-young in the play . This researcher played the character of Kim Mi-young, and the characteristics of comedic acting include exaggeration, repetition, fast tempo, changing tone, and exaggerated physical behavior. Comedic acting comes from a dissonance of reactions. This is because unexpected reactions to stimuli can cause audience laughter. Comedic acting is also important in exaggeration and repetition, which must be based on true acting. The fast tempo of the act and the changing tone of the words also affect comedic acting expressions, and the embodiments of 'slapstick' and 'group dance', which are characteristics of farce acting, play an important role in causing audience laughter. In order for these characteristic elements to show comic effects, the actor's true acting must be the basis. What is important in comedic acting is understanding the narrative flow and features of the text and expressing it accurately. Comedic effects can be sufficiently represented if an actor truly expresses his means and faithfully demonstrates what the text requires. It is hoped that such research will help explore various acting arts, the acting education field, and the theater creation process.

A Study on the Activation Plan for Professional Sport League through Exploration of Inducing Factors of Match Fixing (승부조작 유발요인 탐색을 통한 프로스포츠 활성화 방안)

  • Bang, Shin-Woong;Park, In-Sil;Kim, Wook-Ki
    • Journal of Korea Entertainment Industry Association
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    • v.15 no.3
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    • pp.153-170
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    • 2021
  • This study was attempted to derive strategic implications for activating professional sports by conducting in-depth interviews with professional sports officials such as players, teams, federations, agencies, etc., by searching for factors that cause match fixing and deriving preventive strategies based on them. Eight people with more than 3 years of experience working in professional sports were selected using the snowball sampling technique. Data were collected and analyzed by applying a semi-structured in-depth interview method for them. As a result of the analysis, five core categories (the learning effect from the cartel for entering university, the culture learned in a camp training, the manifestation of the latent learning effect, the negative effect of the human network, the personal disposition) were derived as factors causing match-fixing. As for the strategy to prevent match fixing, first, improving the college entrance examination system oriented on individual capability, second, improving the education system for student athlete, third, establishing a prevention system, fourth, continuing education, fifth, and activating the agent system as the core categories. Implications for the derived research results and future research directions were discussed.

Low serum 25-hydroxyvitamin D levels, tooth loss, and the prevalence of severe periodontitis in Koreans aged 50 years and older

  • Kim, Hyunju;Shin, Min-Ho;Yoon, Suk-Ja;Kweon, Sun-Seog;Lee, Young-Hoon;Choi, Chang-Kyun;Kim, OkJoon;Kim, Young-Joon;Chung, HyunJu;Kim, Ok-Su
    • Journal of Periodontal and Implant Science
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    • v.50 no.6
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    • pp.368-378
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    • 2020
  • Purpose: Vitamin D deficiency may cause bone loss and increased inflammation, which are well-known symptoms of periodontal disease. This study investigated whether serum 25-hydroxyvitamin D (25(OH)D) levels are associated with periodontal disease status and tooth loss. Methods: Cross-sectional data from 5,405 individuals aged ≥50 years (2,253 males and 3,152 females) were obtained from the 2008-2010 Dong-gu study, a prospective cohort study of risk factors for chronic diseases. Periodontal examinations were conducted to evaluate the number of remaining teeth, the periodontal probing depth (PPD), the clinical attachment level (CAL), and bleeding on probing. The percentages of sites with PPD ≥4 mm and CAL ≥4 mm were recorded for each participant. The severity of periodontitis was classified using the Centers for Disease Control and Prevention and the American Academy of Periodontology case definitions. Serum 25(OH)D levels were classified as reflecting severe deficiency, deficiency, insufficiency, or sufficiency. Multivariate linear regression analysis was performed to assess the associations of serum 25(OH)D levels with periodontal parameters and the number of remaining teeth after adjusting for confounders including age, smoking status, alcohol consumption status, month of blood collection, and physical activity. Multivariate logistic regression was used to evaluate the association between serum vitamin D levels and severe periodontitis. An overall statistical analysis and a stratified analysis by sex were performed. Results: Overall, the rates of severe deficiency, deficiency, insufficiency, and sufficiency were 6.5%, 67.9%, 22.4%, and 3.2%, respectively. After adjustment for confounders, vitamin D levels were directly associated with the number of remaining teeth, an association that was significant in males, but not in females. Sufficient serum 25(OH)D was associated with a low frequency of severe periodontitis. Conclusions: This population-based cross-sectional study indicates that low serum 25(OH) D is significantly associated with tooth loss and severe periodontitis in Koreans aged 50 years and older.

Mountain Meteorology Data for Forest Disaster Prevention and Forest Management (산림재해 방지와 산림관리를 위한 산악기상정보)

  • Keunchang, Jang;Sunghyun, Min;Inhye, Kim;Junghwa, Chun;Myoungsoo, Won
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.24 no.4
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    • pp.346-352
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    • 2022
  • Mountain meteorology in South Korea that is covered mountains with complex terrain is important for understanding and managing the forest disaster and forest ecosystems. In particular, recent changes in dryness and/or rainfall intensity due to climate change may cause an increase in the possibility of forest disasters. Therefore, accurate monitoring of mountain meteorology is needed for efficient forest management. Korea Forest Service (KFS) is establishing the Automatic Mountain Meteorology Observation Stations (AMOS) in the mountain regions since 2012. 464 AMOSs are observing various meteorological variables such as air temperature, relative humidity, wind speed and direction, precipitation, soil temperature, and air pressure for every minute, which is conducted the quality control (QC) to retain data reliability. QC process includes the physical limit test, step test, internal consistency test, persistence test, climate range test, and median filter test. All of AMOS observations are open to use, which can be found from the Korean Mountain Meteorology Information System (KoMIS, http://mtweather.nifos.go.kr/) of the National Institute of Forest Science and the Public Data Portal (https://public.go.kr/). AMOS observations with guaranteed quality can be used in various forest fields including the public safety, forest recreation, forest leisure activities, etc., and can contribute to the advancement of forest science and technology. In this paper, a series of processes are introduced to collect and use the AMOS dataset in the mountain region in South Korea.

Analysis of sedation and general anesthesia in patients with special needs in dentistry using the Korean healthcare big data

  • Kim, Jieun;Kim, Hyuk;Seo, Kwang-Suk;Kim, Hyun Jeong
    • Journal of Dental Anesthesia and Pain Medicine
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    • v.22 no.3
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    • pp.205-216
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    • 2022
  • Background: People with special needs tend to require diverse behavioral management in dentistry. They may feel anxious or uncomfortable or may not respond to any communication with the dentists. Patients with medical, physical, or psychological disorders may not cooperate and therefore require sedation (SED) or general anesthesia (GA) to receive dental treatment. Using the healthcare big data in Korea, this study aimed to analyze the trends of SED and GA in special needs patients undergoing dental treatment. It is believed that these data can be used as reference material for hospitals and for preparation of guidelines and related policy decisions of associations or governments for special needs patients in dentistry. Methods: The study used selected health information data provided by the Korean National Health Insurance Service. Patients with a record of use of one of the eight selected drugs used in dental SED between January 2007 and September 2019, those with International Classification of Diseases-10 codes for attention deficit hyperactivity disorder (ADHD), phobia, brain disease, cerebral palsy, epilepsy, genetic disease, autism, mental disorder, mental retardation, and dementia were selected. The insurance claims data were analyzed for age, sex, sedative use, GA, year, and institution. Results: The number of special needs patients who received dental treatment under SED or GA from January 2007 to September 2019 was 116,623. Number of SED cases was 136,018, performed on 69,265 patients, and the number of GA cases was 56,308, implemented on 47,257 patients. In 2007, 3100 special needs patients received dental treatment under SED while in 2018 the number of cases increased 6 times to 18,528 SED cases. In dentistry, ADHD was the most common disability for SED cases while phobia was the most common cause of disability for GA. The male-to-female ratio with respect to SED cases was higher for males (M : F = 64.36% : 35.64%). Conclusion: The application of the SED method and GA for patients with special needs in dentistry is increasing rapidly; thus, preparing guidelines and reinforcing the education and system are necessary.

A Phenomenological Study on the Burnout of Specialized Counselors in the 117 Report Center - Application of the Integrated Working System of Government Departments- (117 신고센터 전문상담 요원의 소진에 관한 현상학적 연구 -정부 부처 통합근무 체제 적용-)

  • Youn, Yang-suk;Kim, Eun-hye
    • Industry Promotion Research
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    • v.7 no.3
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    • pp.85-91
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    • 2022
  • In modern society, the field of life is expanding to complex and diverse fields according to changes in lifestyle. As people's consciousness also changes, various social problems are involved, and countermeasures are being taken in various ways. In particular, as the issue of school violence has become a subject of interest, government-related ministries have jointly set up a reporting center and professional counselors are receiving and consulting on damage reports. Counselors experience mental and physical exhaustion in the course of their work. Therefore, the need to contribute to effective counseling work is raised by studying the factors that cause burnout. This study collected the experiences of 10 counselors working at 117 reporting centers from February 2019 to May 2020 through interviews and analyzed them with Colaizzi's phenomenological research method. The exhaustion factors derived from the results of the study were first experiences such as conflict between counselors during the period of institutional integration in the "117 reporting center experience", and secondly, professional counselors experienced emotional exhaustion, inhumanization, and lack of achievement. In order to prevent and overcome the exhaustion factors of counseling agents, it was necessary to prepare measures to promote fraud. This is expected to be useful data for improving the working environment of special job counselors in the era of industrialization and informatization in which various anonymous counseling methods are used.

Study of Imaging of Submarine Bubble Plume with Reverse Time Migration (역시간 구조보정을 활용한 해저 기포플룸 영상화 연구)

  • Dawoon Lee;Wookeen Chung;Won-Ki Kim;Ho Seuk Bae
    • Geophysics and Geophysical Exploration
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    • v.26 no.1
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    • pp.8-17
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    • 2023
  • Various sources, such as wind, waves, ships, and gas leaks from the seafloor, forms bubbles in the ocean. Underwater bubbles cause signal scattering, considerably affecting acoustic measurements. This characteristic of bubbles is used to block underwater noise by attenuating the intensity of the propagated signal. Recently, researchers have been studying the large-scale release of methane gas as bubble plumes from the seabed. Understanding the physical properties and distribution of bubble plumes is crucial for studying the relation between leaked methane gas and climate change. Therefore, a water tank experiment was conducted to estimate the distribution of bubble plumes using seismic imaging techniques and acoustic signals obtained from artificially generated bubbles using a bubble generator. Reverse time migration was applied to image the bubble plumes while the acquired acoustic envelope signal was used to effectively estimate bubble distribution. Imaging results were compared with optical camera images to verify the estimated bubble distribution. The water tank experiment confirmed that the proposed system could successfully image the distribution of bubble plumes using reverse time migration and the envelope signal. The experiment showed that the scattering signal of artificial bubble plumes can be used for seismic imaging.