• Title/Summary/Keyword: 한서

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Estimation of SO2 emissions in large point sources at Dangjin City using airborne measurements (항공관측 결과를 활용한 당진시 대형사업장에서의 황산화물 배출량 평가)

  • Kim, Yong Pyo;Kim, Saewung;Kim, Jongho;Lee, Taehyoung
    • Particle and aerosol research
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    • v.16 no.4
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    • pp.107-117
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    • 2020
  • Based on the airborne measurement results over a coal fired power plant and steel work in Dangjin city, SO2 emission amounts of each site are estimated (top-down emission). Airborne measurements were carried out on May-June and October-November 2019. The estimated SO2 emission in 2019 for the power plant was 1502.1 kg/hr and that for the steel work was 2850.5 kg/hr, higher as much as a factor of 2.5 and 2.0, respectively, than the emission amounts provided by both facilities (bottom-up emission). The outcomes strongly illustrates that well designed airborne observations can serve a quantitative diagnostic tool for bottom-up emission estimates. Further research direction to improve the reliability of the top-down emission estimates is suggested.

A Comparison Study of College Student Pilots' Learning Styles in Flight Training School: applying Kolb's Learning Style Model (국내·외 학생조종사들의 비행훈련 학습양식 비교 연구: Kolb 학습양식 모델을 적용하여)

  • Hwang, Jae-Kab;Lee, Gun-Young;Yoon, Han-Young
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.1
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    • pp.197-207
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    • 2021
  • According to the analysis of Kolb's learning style, Korean university student pilots interpret and attach meaning to themselves. Moreover, as the school year progresses, they enter the flight-training course with a 100 % diverger style, which is a variety of thoughts and imaginative learning styles. As the school year progresses, some changes occur with accommodator (11.1%) and assimilator (15.9%) styles. On the other hand, most students remain as the diverger style (71.4%). In the case of U.S. student pilots, most in first-year are assimilator (35.5%) and converger (24.3%) styles, and the proportion of the converger style increases as the senior year is approached. In the first grade, most Chinese student pilots are assimilators (41.5%) and convergers (28.4%), but in the higher grade, the proportion of assimilators and convergers decrease, and the proportion of diverger styles increases dramatically. In the fourth grade, the accommodator was similar to the first grade, but the converger style continued to decrease (41.5% in the first grade and 27.0% in the fourth grade).

Enhancement of combustion efficiency of a air-cooled combustor system with single F.D. Fan Using CFD (전산유체역학을 이용한 단일 송풍기가 적용된 공냉식 연소설비의 효율개선)

  • Kim, Min-Choul;Shon, Byung-Hyun;Lee, Jae-Jeong;Park, Hung-Suck
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.6
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    • pp.460-468
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    • 2021
  • This study investigated the enhanced combustion efficiency of an "air-cooled combustion system" with single F.D. fan, and performed a numerical analysis for the operation and design conditions to increase the combustion efficiency. The combustion efficiency in an actual combustor was compared before and after the structure modification. Numerical analysis for application of a single fan revealed the difficulty of forming a turbulence for circular combustion conditions. This is because the supply ratio of combustion air supplied into 2 flow paths becomes irregular in the combustion furnace due to a change in friction force and pressure in each flow path. Subsequently, two methods of supplying air into the combustion furnace were analyzed numerically to obtain the optimal combustion conditions of an air-cooled combustion system. The first method involved injecting the preheated combustion air after a 180~360 degree rotation from the outer wall, whereas in the second method, the combustion air was injected into the combustion furnace in a tangential direction after primary heat exchange outside the combustion furnace, by applying a rotatable vane structure in the combustion furnace. Results reveal that application of a single F.D. fan to the air injection into a rotatable combustion furnace is desirable for optimization of the combustion conditions for applying a duct structure having a dual cooling wall for the cooling of the outer wall of the combustion furnace, and for maintaining perfect mixing in the combustion furnace. We therefore confirmed enhanced combustion efficiency by comparing the actual combustion efficiency before and after structure modification.

Critical Review on Educational Gerontology in Journal of the Korean Gerontological Society (한국노년학 30년을 통해 본 노년교육 관련 연구)

  • Han, Jungran
    • 한국노년학
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    • v.28 no.4
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    • pp.831-846
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    • 2008
  • The purpose of this study was to review papers published in the Journal of Korean Gerontological Society(1980-2008). For this purpose, the 55 articles on the educational gerontology were collected from the Journal. The published time, the number of authors, the author's positions, subjects, type of the researches, methods, the statistical techniques, topics of the educational gerontology, and so on were analyzed for this research. The results of this study were as follows: (1)The articles regarding on the educational gerontology took 7.14% in the Journal of Korean Gerontological Society. (2)The case of the quantitative researches for the elderly done by single author, performed without fund, through the questionnaire survey, and with more than two statistical techniques were the most common. Based on this researches, the organization of the major field or some courses on the educational gerontology, more research funds for the educational gerontology, and the efforts on the various research methods of themes and objects are recommended for better researches on the educational gerontology. Finally, we must expand our interests for the elderly's empowerment as a learner and the educational gerontology.

Poetic Aspects and Meanings of Experiences in Staying in Mountains Presented in Toegye's Poems about Mt. Cheongryang (퇴계(退溪)의 청량산시(淸凉山詩)에 나타난 유산(遊山)체험의 시화(詩化) 양상과 의미)

  • Choi, Eun Sook
    • (The)Study of the Eastern Classic
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    • no.56
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    • pp.9-33
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    • 2014
  • This paper aims to look into text of Toegye Lee Hwang's poem Cheongryangsan (Mt. Cheongryang). For that, the poetic aspects of experiences in staying in mountains presented in the poem were classified into materialistic aspect, a method of subject proposal, subject recognition and orientation to examine such aspects, and their respective meanings and limits were considered. First, from the materialistic aspect, the poem about Mt. Cheongryang can be divided into a case of materializing acts in Mt. Cheongryang and a case of materializing an individual scenery of Mt. Cheongryang itself. Second, from an aspect of methods of subject proposal, the poem can be divided into a case in which the space of Mt. Cheongryang is proposed syntagmatically and abstractly and a case in which each scenery is proposed by it being divided partially. Third, from an aspect of subject recognition and orientation, in case Mt. Cheongryang is realized as a solitary space separated far from the world, poetic self aims at reflection. However, in case Mt. Cheongryang is realized as a space for staying with friends and disciples, poetic self aims at communication. The above-mentioned difference is caused by the fact that Toegye had such an experience in Mt. Cheongryang twice at the interval of 10 years. This study is significant in that it intensively looked into Toegye' experience in Mountains and the poetic text which have not been studied and that Toegye's recognition and orientation of a space were discriminatively revealed.

Investigation on Design Aspects of the Constructed Wetlands for Agricultural Reservoirs Treatment in Korea (농업용 저수지 수질개선을 위한 국내 인공습지 설계 및 시공실태 조사)

  • Kim, Youngchul;Choi, Hyeseon;Kim, Lee-Hyung
    • Journal of Wetlands Research
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    • v.23 no.2
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    • pp.189-200
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    • 2021
  • To improve the water quality of agricultural reservoirs, constructed wetlands are applied in many places. These are technologies that establish ecosystems and important design factors include water depth distribution, inflow and outflow, water flow distribution, hydraulic residence time, water quality treatment efficiency, aspect ratio, and the distribution of open water and covered water surfaces. For high efficiency during the operation of a constructed wetland, the design needs to be optimized and this requires consideration of the different types and length of the intake dam as well as the type and connection of wetland cells. Therefore, this study was conducted to investigate and suggest factors that needs to be considered during the design and for efficient operation measures through field surveys of 23 constructed wetlands that have been established and operated in agricultural reservoirs. Results of the field investigation shows that several sites were being operated improperly due to the malfunctioning or failure of the water level sensors, sedimentation in the intake dam, and clogging of the mechanical sluice frames. In addition, it was found that as the length of the inlet channel increases, the ecological disconnection between the intake dam upstream and the wetland outlet downstream also increases and was identified as a problem. Most of the wetlands are composed of 2 to 5 cells which can result to poor hydraulic efficiency and difficulty in management if they are too large. Moreover, it was found that the flow through a small wetland can be inadequate when there are too many cells due to excessive amounts of headloss.

Absorption characteristic of carbon dioxide in Ionic Liquids based sulfite anion in the pre-combustion condition (연소 전 조건에서 음이온이 Sulfite계인 이온성 액체의 CO2 흡수 특성)

  • Baek, Geun Ho;Jang, Hyun Tae;Cha, Wang Seog
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.3
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    • pp.763-769
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    • 2021
  • In this study, ionic liquids were synthesized to remove carbon dioxide (CO2) on a laboratory scale. The vapor-liquid absorption equilibrium device (VLE) was used to investigate the carbon dioxide absorption capacity. In the regeneration study, the absorption capacity after regeneration was reduced by approximately 7% for all ionic liquids, in which the anion was sulfite-based, showing excellent regeneration. Ethyl sulfite showed the highest absorption capacity of CO2 among the ionic liquids based on the sulfite anion. In particular, the absorption capacity of [beim] ethyl sulfite was 1.1 mol CO2 / mol IL at an absorption equilibrium pressure of 22 bar. In the regeneration study, the absorption capacity after regeneration was reduced by approximately 7% for all ionic liquids, in which the anion was sulfite-based, from which regeneration is outstanding. After the absorption experiment, the viscosity of the sample tended to decrease by approximately 8% compared to that before the absorption experiment. On the other hand, the absorbent was synthesized in the first step. Moreover, the raw material used is also inexpensive and has excellent reproducibility and highly stable absorbent capacity.

Verification of Entertainment Utilization of UAS FC Data Using Machine Learning (머신러닝 기법을 이용한 무인항공기의 FC 데이터의 엔터테인먼트 드론 활용 검증)

  • Lee, Jae-Yong;Lee, Kwang-Jae
    • Journal of Korea Entertainment Industry Association
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    • v.15 no.4
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    • pp.349-357
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    • 2021
  • Recently, drones are rapidly becoming common and expanding. There is a great need for diversity in whether drone flight data can be used as entertainment technology analysis data. In particular, it is necessary to check whether it is possible to analyze and utilize the flight and operation process of entertainment drones, which are developing through autonomous and intelligent methods, through data analysis and machine learning. In this paper, it was confirmed whether it can be used as a machine learning technology by using FC data in the evaluation of drones for entertainment. As a result, FC data from DJI and Parrot such as Mavic2 and Anafi were unable to analyze machine learning for entertainment. It is because data is collected at intervals of 0.1 second or more, so that it is impossible to find correlation with other data with GCS. On the other hand, it was found that machine learning technologies can be applied in the case of Fixhawk, which used an ARM processor and operates with the Nuttx OS. In the future, it is necessary to develop technologies capable of analyzing the characteristics of entertainment by dividing fixed-wing and rotary-wing flight information. For this, a model shoud be developed, and systematic big data collection and research should be conducted.

A Study of Black Comedy and Creativity Elements in Joon Ho Bong's Films -With Emphasis on - (봉준호 감독 영화에 나타난 블랙코미디 요소와 창의성 연구 - 영화<기생충>을 중심으로 -)

  • Kim, Seong-Hoon
    • The Journal of the Korea Contents Association
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    • v.21 no.11
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    • pp.243-256
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    • 2021
  • is a film that lifted Director Joon Ho Bong and Korea to the world-class level. A number of researchers have released findings of studies on based on their own interests and perspectives. The current study discussed the historical facts of black comedy in film and how black comedy from play has been used for epic characteristics and formal measures, although it was not a specific rule, through the perspectives of contemporary writers, such as Beckett, Ionesco, Durrenmatt, and Brecht. Some tools used for comedies and tragedies shared the same concept with black comedy in film and black comedy was a unique characteristic of film. The study analyzed how black comedy was signified in for paradox and nonalignment of purpose/intent and consequences as epic characteristics and parody, grotesque, and coincidence as formal measures. It also discussed the meaning of Director Bong's black comedy in and how the audience accepted it. Both the contemporary writers and Director Bong has a compassionate perspective, but the his was different from the work of other contemporary writers. Therefore, the study discussed his creativity behind .

Study on the Human Error Prevention Collision Avoidance Model using Merchant Ship Collision Accident Analysis (상선 충돌사고 분석을 이용한 인적과실 예방 충돌회피모델 연구)

  • Kim, Do-Hoon
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.6
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    • pp.918-927
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    • 2022
  • The purpose of this study was to investigate the causes of collisions by examining 668 cases of merchant ship collision accidents that occurred during the past 12 years (2010-2021) and analyzed them statistically. Further, the analysis results were applied to propose a human error prevention collision avoidance (HEPCA) model. The statistical annual report of the Korea Maritime Safety Tribunal (KMST) and the collision investigation report were investigated to collect data on the causes of collisions of merchant ships, and frequency analysis was performed using the statistical analysis tool, SPSS Statistics. In the first-stage analysis, the causes of collisions were analyzed targeting 668 merchant ship collision accidents, and in the second-stage analysis, the identified maximum frequency cause factors were analyzed in detail. The analysis results identified that 98 % of the cause of the collision was the human error of the navigator, and the highest frequency was in the order of neglect of look-out > violation of navigation regulations > improper maneuvering. The cause of the neglect of look-out was mainly neglecting continuous monitoring after the first recognition of the target ship. The HEPCA model for human error prevention was proposed by applying the analysis results to the collision case of the investigation report. The results of this study are expected to be used as educational materials at marine navigator educational institutions and in practice for avoiding collisions caused by human errors of navigators.