• 한국환경기술학회지
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• 제19권6호
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• pp.528-535
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• 2018

본 연구에서는 전산유체역학(CFD) 모델을 이용하여, 건물 외관비에 따른 건물협곡에서의 소용돌이 현상을 재현하고 정량적인 해석을 시도하였다. 이를 위하여 건물협곡의 폭(W)을 기준으로 건물의 길이(L) 및 높이(H) 증가에 따른 민감도 실험을 수행하였으며, 건물협곡에서의 바람 벡터장과 2차 역회전 소용돌이의 형성 등을 분석하였다. 수평소용돌이의 경우에는 건물의 길이 증가에 따라 성장하다가 L/W=2.5부터 건물협곡의 중앙부에서 벡터의 크기 약화 및 방향 변화 등의 조짐이 보이기 시작하였고, L/W=3.0 이상에서 흐름이 분리되어 1차 소용돌이는 약화되고 건물협곡의 안쪽에서 2차 역회전 소용돌이가 형성되었다. 연직소용돌이의 경우에는 건물의 높이 증가에 따라 성장하다가 H/W=2.5부터 건물협곡의 하부에서 벡터의 방향전환 현상이 나타나기 시작하였고, H/W=3.5 이상의 조건에서 1차 소용돌이는 약화되고 2차 역회전 소용돌이가 형성되었다.

• 한국정보통신학회논문지
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• 제24권10호
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• pp.1300-1305
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• 2020

RS-232 또는 RS-422의 단순한 통신 구조로 인하여 여전히 선박 대부분은 이를 기반으로 한 통신인프라를 내부 네트워크 환경으로 구축하고 있다. NMEA-0183은 선교 항해 당직 경보시스템(BNWAS: Bridge Navigational Watch Alarm System)을 위한 세 개의 계층을 구성하는 규격 중 하나이며 다양한 통신방식을 제공하지만, 여전히 이미 구축된 RS-232 나 RS-422를 사용하고 있다. 선교 항해 당직 경보시스템은 선박 상태 및 환경요소 등을 감지하는 각종 센서, GPS, AIS 등 다양한 장치들을 연결하여 운영한다. 본 논문에서는 이 NMEA-0183 환경에서 영상센서의 적용 가능성을 확인하고 영상데이터를 스트리밍하기 위한 기법을 제안한다. 그리고 동인 통신채널을 공유하는 다른 센서들로부터 생성된 NMEA 메시지 개수에 따른 영상품질의 변화를 분석하고 적용 타당성을 입증한다.

• 한국해양공학회지
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• 제34권6호
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• pp.394-405
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• 2020

To assess the station-keeping performance of floating structures in the Arctic region, the ice load should be considered along with other environmental loads induced by waves, wind, and currents. However, present methods for performance evaluation in the time domain are not effective in terms of time and cost. An ice load generation module is proposed based on the experimental data measured at the KRISO ice model basin. The developed module was applied to a time domain simulation. Using the results of a captive model test conducted in multiple directions, the statistical characteristics of ice loads were analyzed and processed so that an ice load corresponding to an arbitrary angle of the structure could be generated. The developed module is connected to commercial dynamic analysis software (OrcaFlex) as an external force input. Station-keeping simulation in the time domain was conducted for the same floating structure used in the model test. The mooring system was modeled and included to reflect the designed operation scenario. Simulation results show the effectiveness of the proposed ice generation module and its application to station-keeping performance evaluation. Considering the generated ice load, the designed structure can maintain a heading angle relative to ice up to 4°. Station-keeping performance is enhanced as the heading angle conforms to the drift direction. It is expected that the developed module will be used as a platform to verify station-keeping algorithms for Arctic floating structures with a dynamic positioning system.

• Ocean and Polar Research
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• 제44권3호
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• pp.191-207
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• 2022

Using the results of CTD casts made in Spring from 2017 to 2021, in this study we investigated the water mass distribution and occurrence of temperature inversion in the western seas of Jeju Island in spring. The distribution of water masses was characterized by cold and fresh water in the northwest and warm and saline water in the southeast, forming a strong thermohaline front running in the southwest-to-northeast direction. Strong temperature inversion mainly occurred in the frontal boundary when the cold water intrudes beneath the warm water at depths of 30-50 m. Analysis of the mixing ratio demonstrated that Jeju Warm Water is dominantly distributed in the western seas of Jeju Island, but its ratio can be modified depending on the southward extension of Yellow Sea Cold Water (YSCW). Results of in situ measurement showed that in 2020, the YSCW largely expanded to the western seas of Jeju Island, occupying approximately 40 % of the mixing ratio. Due to the expansion of YSCW, a strong thermohaline front was formed in the study area, thereby causing thick and strong temperature inversion. On the other hand, in 2018 the mixing ratio of YSCW was minimum (~18%) during the study period of 2017-2021, and thus a relatively weak frontal boundary was formed, without the occurrence of temperature inversion. The observational results also suggest that the interannual changes of water mass distribution and the associated temperature inversion in the western seas of Jeju Island are closely related with wind-driven Yellow Sea circulation in spring, which is the summer monsoon transition period.

• 한국인터넷방송통신학회논문지
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• 제22권1호
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• pp.21-27
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• 2022

사회가 발전하고 복잡해짐에 따라 재난의 종류도 미세먼지, 전염병 등과 같이 새롭고 다양하게 발생하고 있다. 하지만 기존에는 이러한 재난에 대비할 수 있는 정확한 정보를 제공하는 전관방송 시스템이 없었다. 본 논문에서는 공공 데이터와 IoT 센서로부터 수집된 오염된 대기질 데이터를 분석하여 자동으로 경보를 방송하는 전관방송 시스템을 제안한다. 대기질에 따라 경보의 단계가 달라지며, 공공데이터에서 제공하는 정보는 측정소로부터의 거리나 풍향 등 다양한 요인으로 인해 안내 지역과 상당한 차이가 있는 결과를 나타내기도 한다. 이를 보완하기 위해 공공데이터에서 가져온 데이터와 현장 IoT센서에서 얻은 데이터를 비교 분석하여 방송하는 방법을 제안하고자 한다.

• 스마트미디어저널
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• 제12권3호
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• pp.120-128
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• 2023

산업재해로 인한 피해를 줄이기 위해 다양한 ICT 기술이 지속적으로 개발되고 있으며, 센서, IoT, 빅데이터, 머신러닝 및 인공지능 등을 활용하여 산업재해 발생 시 피해를 최소화하고자 하는 연구가 진행되고 있다. 본 논문에서는 산업 현장의 밀폐구간, 산악, 해양, 탄광 등의 통신 음영지역에서 디바이스 간 다자간 통신 및 스마트 중계기와의 통신이 가능한 스마트 디바이스의 설계 방안을 제안한다. 제안된 스마트 디바이스는 작업자 위치, 이동 속도 등 작업자 정보와 지형, 풍향, 온도, 습도 등 환경정보를 수집하고 작업자 상호 간의 안전거리를 확보하여 위험 상황 발생 시 경고가 가능하며 헬멧에 부착할 수 있도록 설계하였다. 이를 위해, 스마트 디바이스에 필요한 기능적 요구사항과 스마트 디바이스 내의 센서와 모듈을 이용하여 요구사항을 구현하기 위한 설계 방안과 스마트 디바이스의 성능평가를 위한 지표를 도출하고 산악지역에서의 성능평가를 위한 평가환경을 제안한다.

• 건축역사연구
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• 제32권4호
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• pp.19-33
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• 2023

This study investigated the architectural expression of Taekpungdang(澤風堂, The Pond and Wind House) built by the Neo-Confucianist Taekdang Lee Sik(澤堂 李植, 1584~1647) from the perspective of the symbolic system of the Zhōuyì(『周易』, Classic of Changes). This study examined the historical context, personal history, and construction process of Taekpungdang at the time of its creation through his collection of writings, the Taekdanggip(澤堂集). The study also estimated the original form of Taekpungdang through field surveys and historical evidence. In addition, the architectural principles and architectural expressions inherent in the Taekpungdang were derived based on the symbolic system of "taekpungdaegwa"(澤風大過) which is Lee Sik's divination and one of the 64 trigrams in the Zhōuyì. Lee Sik, who was knowledgeable in the Zhōuyì, used divination to cope with the chaotic political situation and his own misfortunes. Accordingly, He determined the direction of his life and planned the surrounding environment, architectural structure, and form of Taekpungdang based on the rules and meanings of his divination system. He embodied the architectural space of Taekpungdang with the concept of time and space inherent in the divination of "daegwa",(大過, great exceeding). In addition, he expressed the principle of the generation of palgue,(八卦, the eight trigrams for divination) and the principle of the co-prosperity of ohaeng(五行, the five elements) through the composition of walls and windows of the house. The images of Taekpungdaegwae, which are dongyo(棟撓 wood submerged in the pond) and taekmyeolmok(澤滅木, shaking pillars), were manifested in the form of buildings. Therefore, Taekpungdang can be considered a remarkable example of a building designed through the thorough utilization of the Zhōuyì divination system.

• 현장농수산연구지
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• 제11권1호
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• pp.3-19
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• 2009

The purpose of this study was to systemize the 'Eagi(理氣)' theory in Feng Shui which has been neglected in Korea because of its difficulties in the current Feng Shui theory and to make it easier to apply in the art of placement. The study also analysed the characteristics of the location of a sample village in terms of Feng Shui. Besides the placement analysis, the interpretation of the Yangtaek(陽宅) theory was analysed on the layout of the outdoor space of the building. As the initial step, various theories about Feng Shui were investigated. Based on those, the framework of the Feng Shui theory was summarized for application to the case study. Yangtaeksamyo(陽宅三要) was referred to for consideration of Feng Shui theory outside the residential buildings. At the same time, configurational analysis of the ground was carried out with the naked eye and actual measurements were taken using a specific compass(佩鐵). The results were summarized as follows : First, the 'Eagi' theory in Feng Shui, which finds a 'lucky site(穴)' selects the 'geomagnetic aspect(坐向)' by analyzing the natural forces of wind and water. In this theory, the aspect was regarded of most importance. 'Yangtaek Feng Shui (陽宅風水)' was the theory that people's ups and downs depends on the direction of the place where they live on, and was developed on the basis of 'I ching(周易)'. Second, the village and the house in the case study have been considered as lucky places from old times and this was equally verified by the 'Eagi (理氣)' theory and the "Yangtaek (陽宅)' theory.

• 천문학회보
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• 제46권2호
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• pp.62.1-62.1
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• 2021

Interstellar objects originate from other stellar systems. Thus, they contain information about the stellar systems that cannot be directly explored; the information includes the formation and evolution of the stellar systems and the possibility of life. The examples observed so far are 1l/Oumuamua in 2017 and 2l/Borisov in 2019. In this talk, we present the possibility of detecting interstellar objects using the Heliospheric Imagers designed for space weather research and forecasting by observing solar wind in interplanetary space between the Sun and Earth. Because interstellar objects are unpredictable events, the detection requires observations with wide coverage in spatial and long duration in temporal. The near-real time data availability is essential for follow-up observations to study their detailed properties and future rendezvous missions. Heliospheric Imagers provide day-side observations, inaccessible by traditional astronomical observations. This will dramatically increase the temporal and spatial coverage of observations and also the probability of detecting interstellar objects visiting our solar system, together with traditional astronomical observations. We demonstrate that this is the case. We have used data taken from Solar TErrestrial RElation Observatory (STEREO)/Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI) HI-1. HI-1 is off-pointed from the Sun direction by 14 degrees with 20 degrees of the field of view. Using images observed from 2007 to 2019, we have found a total of 223 small objects other than stars, galaxies, or planets, indicative of the potential capability to detect interstellar objects. The same method can be applied to the currently operating missions such as the Parker Solar Probe and Solar Orbiter and also future L5 and L4 missions. Since the data can be analyzed in near-real time due to the space weather purposes, more detailed properties can be analyzed by follow-up observations in ground and space, and also future rendezvous missions. We discuss future possible rendezvous missions at the end of this talk.

• 산업진흥연구
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• 제8권3호
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• pp.163-174
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• 2023

심곡서원은 조선 중기의 학자이며 정치가였던 조광조의 뜻을 기리기 위해 세운 서원이다. 풍수적 길지에 자리하고 있는데, 주산은 무곡금성체로, 원와혈을 맺고 있으며 안산은 탐랑목성체이다. 제향 공간을 혈처에 배치한 제향중심 서원이며, 사당을 중심으로 좌청룡과 우백호, 주작과 현무가 혈처를 잘 보호하고 있다. 사우를 중심으로 배치된 전형적인 중심 축선형 공간 배치이다. 강당을 전면에 배치하고 제향 공간인 사당을 후면에 배치하는 전학후묘의 형태이다. 사당을 중심으로 좌측에 천원지방의 원리를 응용한 연지를 조성하여 유식 공간과 미기후의 조절 기능, 화재시 소화의 기능을 담당한다. 건축물의 좌향과 방위, 위치 등을 결정하는 데 있어 풍수가 중요한 역할을 한다. 따라서 지형이나 바람 그리고 물의 흐름과 방위 등으로부터 자연환경과 인간의 상관관계를 정확히 파악하여 자연과 사람이 하나 되는 풍수적 공간구성은 천인합일의 미학정신의 구현이라 할 수 있다.