전산유체역학을 통한 간척지 내 벤로형 온실의 자연환기량 분석

이상연,이인복,권경석,하태환,여욱현,박세준,김락우,조예슬,이승노,Lee, Sang-Yeon,Lee, In-Bok,Kwon, Kyeong-Seok,Ha, Tae-Hwan,Yeo, Uk-Hyeon,Park, Se-Jun,Kim, Rack-Woo,Jo, Ye-Seul,Lee, Seung-No 한국농공학회 2015 한국농공학회논문집 Vol.57 No.6

Recently, the Korean government announced a new development plan for a large-scale greenhouse complex in reclaimed lands. Wind environments of reclaimed land are entirely different from those of inland. Many standard books for ventilation design didn't include qualitative standard for natural ventilation. In this study, natural ventilation rates were analyzed to suggest standard for ventilation design of venlo type greenhouse built on reclaimed land. CFD (Computational Fluid Dynamics) simulation models were designed according to the number of spans, wind conditions and vent openings. The wind profile at a reclaimed land was designed using ESDU (Engineering Sciences Data Unit) code. Using the designed CFD simulation model, ventilation rates were computed using mass flow rate and tracer gas decay method. Additionally computed natural ventilation rates were evaluated by comparing with ventilation requirements. As a result of this study, ventilation rates were decreased with increasing of the number of spans. Ventilation rates were linearly increased with increasing of wind speed. When the wind speed was $1.0\;m{\cdot}s^{-1}$, only side vent was open and wind direction was $45^{\circ}$, homogeneity of ventilation rate at 0~1 m height is the worst. Finally, chart for computing natural ventilation rate was suggested. The chart was expected to be used for establishing standard of ventilation design.

검진센터를 이용한 고객의 만족도 조사

이상연,조승진,최승렬,김순희,엄진영,장현오,유형관,Lee, Sang-Yeon,Jo, Seung-Jin,Choe, Seung-Ryeol,Kim, Sun-Hui,Eom, Jin-Yeong,Jang, Hyeon-O,Yu, Hyeong-Gwan 한국건강관리협회 2006 한국건강관리협회지 Vol.4 No.1

Background: This survey has focused on Client-Satissfaction for health examination services of Korean Association of Health Promotion, This research will help final weak point and promote the qualify of the services provided. Methods: This survey was done on 400 visitors of the clinic. Between Jan. 2 and May 3l, 2005 Questionaires were distributed to the visitors with a informed consent. Results: The visitㅐrs for health examination at Daegu chapter of Korean Association of Health promotion had high-school or higher level education(79.8%) and were self-employed persons with an average monthly income of 3~4 million won(27.7%), and housewives(33.0%). The most frequent complaints of the visitors was the difficulty in access to the center. The motives for taking health examination were cheap cost of examination(32.7%) and recommendation by fami1y members and friends(42.0%). The possitive attitude of the employees of KAHP were kind reponses to phone calls(85.3%) and kind explanations to questions(68.5%). Regarding the merits of the examination at KAHP, appropriate equipments(68.0%) and quality of equipments(66.0%) and they expressed their desire for further use revisit to the KAHP(85.3%).Conclusions. It is concluded that this KAHP is providing services meeting their demands in cost and qualitatively of health examination. However, it is noted that there are several weak points in own system that make own clients uneasy in taking health examination. They have to be solved by providing transporting for accession, kind attitudes and comfortable facilities.

문화예술 지식 콘텐츠 현황과 전망

이상연,Lee, Sang-Yeon 한국데이터베이스진흥원 2005 디지털콘텐츠 Vol.2 No.-

최근 수년 전부터 국내 언론매체들에서는 우리나라가‘IT 강국’, ‘인터넷 선진국’이란 말이 가끔씩 나오곤 한다.그것은 무엇보다도 전국적으로 세계 최고의 고속 케이블망을 설치했고, 디지털 기술이 발전돼 있다는 데에 기인하고,그 케이블망으로써 전국 어디서나 인터넷을 접하고 빠른 속도로 이용할 수 있다는 것을 말하는 것 같다. 그러면 그렇게 발달된 기술로써 항시 접할 수 있는 인터넷을 통해 우리나라 사람들을 무엇을 하고 있을까? 각자의 취향과 관심사에 따라 인터넷을 이용하는 분야가 다르겠지만, ‘문화의 시대’라는 21세기에 특히 대중문화 산업이 각광받고 있는 요즈음 문화예술에 관한 지식정보 콘텐츠들을 찾아보자.

무궁화! 우리회사는 이렇게 재배한다.

이상연,Lee, Sang-Yeon 한국조경수협회 2001 造景樹 Vol.61 No.3

전이 구간(트렌지션 커터존)의 최적 디스크커터 각도 산정에 관한 수치해석 연구

이상연,송기일,Lee, Sang Yun,Song, Ki-il 한국터널지하공간학회 2021 한국터널지하공간학회논문집 Vol.23 No.1

Tunnel boring machine (TBM)의 설계에 있어서 지반과 직접적으로 맞닿아 절삭을 담당하는 커터헤드의 설계에 따라서 장비의 굴진효율이 달라지게 된다. 디스크커터는 배치되는 위치에 따라 센터 커터 존, 이너 커터 존, 트렌지션 커터 존으로 구분된다. 기존에도 페이스커터의 최적 절삭조건을 규명하기 위한 연구는 많이 진행되어 왔으나, 트렌지션 커터의 최적 절삭조건을 규명하기 위한 연구는 상대적으로 미진하였다. 본 연구에서는 트렌지션 커터의 최적의 절삭조건을 규명하기 위해 개별요소법 수치해석을 수행하고 트렌지션 커터 사이의 각도에 따른 비에너지 곡선을 작도하여 최적 절삭조건을 알아보고자 하였다. 수치해석 결과 전이영역에서 최소 비에너지를 보이는 트렌지션 커터 사이의 각도 9°인 것으로 확인되었다. 이를 트렌지션 커터의 경사각에 따라 3가지 영역으로 구분하고 영역별 디스크커터 사이의 각도와 비에너지를 정리한 결과 트렌지션 커터의 경사각이 커질수록 최적 비에너지를 보이는 트렌지션 커터 사이의 각도는 10°에서 8°까지 점차 감소하는 경향을 보였다. 이러한 결과는 기존에 사용되고 있는 트렌지션 커터의 설계 결과와 유사한 경향으로써, 본 연구의 결과를 밑받침한다. In the design of a tunnel boring machine (TBM), the excavation efficiency of the equipment depends on the design of the cutter head, which is directly in contact with the ground. Especially, the allocation of disc cutter is crucial issue. Disc cutters can be divided into center cutter zone, inner cutter zone and transition cutter zone depending on where they are placed. Many studies have been conducted to identify optimal cutting conditions for face cutters. However, research to determine the optimal cutting conditions for the transition cutter has been relatively incomplete. In this study, to identify the optimal cutting conditions for the transition cutter, numerical analysis using discrete element method was performed, and the specific energy curve according to the angle between the transition cutters was drawn to find out the optimum cutting conditions. The results show that the angle between the transition cutters showing minimum specific energy in the transition cutter zone is 9°. Transition cutter zone was divided into three sections according to the slope angle of the transition cutter. It is also found that, the greater the slope angle of the transition cutter. This finding shows good agreement with the present design of transition cutter zone.

디지털트윈 기반 아쿠아팜 동향 및 발전 방향

이상연,여욱현,김준규,조성균,S.Y. Lee,U.H. Yeo,(J.G. Kim,S.K. Jo 한국전자통신연구원 2023 전자통신동향분석 Vol.38 No.3

With the increasing demand for seafood and technological advancement in aquaculture, the industry has continuously grown. On the other hand, digital twins have been actively applied to various industries. Aquaculture deals with live aquatic animals that are sensitive to growth environment management. Hence, applying a digital twin to smart aquaculture may lead to a substantial economic benefit because it enables the optimization of different variables. We analyze the status of digital twin development in agriculture. The services of the aquafarm digital twin are divided into 1) data management, 2) optimization, and 3) intelligence. Standardization related to the aquafarm digital twin is also discussed. Based on the analyses, the development stage of aquafarm digital twin is defined, and directions of technology development are suggested.

내부 광전자방출 분광법을 이용한 Pt/HfO₂/p-Si Metal-Insulator-Semiconductor 커패시터의 쇼트키 배리어 분석

이상연,서형탁,Lee, Sang Yeon,Seo, Hyungtak 한국재료학회 2017 한국재료학회지 Vol.27 No.1

In this study, we used I-V spectroscopy, photoconductivity (PC) yield and internal photoemission (IPE) yield using IPE spectroscopy to characterize the Schottky barrier heights (SBH) at insulator-semiconductor interfaces of Pt/$HfO_2$/p-type Si metal-insulator-semiconductor (MIS) capacitors. The leakage current characteristics of the MIS capacitor were analyzed according to the J-V and C-V curves. The leakage current behavior of the capacitors, which depends on the applied electric field, can be described using the Poole-Frenkel (P-F) emission, trap assisted tunneling (TAT), and direct tunneling (DT) models. The leakage current transport mechanism is controlled by the trap level energy depth of $HfO_2$. In order to further study the SBH and the electronic tunneling mechanism, the internal photoemission (IPE) yield was measured and analyzed. We obtained the SBH values of the Pt/$HfO_2$/p-type Si for use in Fowler plots in the square and cubic root IPE yield spectra curves. At the Pt/$HfO_2$/p-type Si interface, the SBH difference, which depends on the electrical potential, is related to (1) the work function (WF) difference and between the Pt and p-type Si and (2) the sub-gap defect state features (density and energy) in the given dielectric.

Density Functional Theory Calculation of Molecular Structure and Vibrational Spectra of Dibanzofuran in the Ground Lowest Triplet State.

이상연,Lee, Sang Yeon Korean Chemical Society 2001 Bulletin of the Korean Chemical Society Vol.22 No.6

The molecular geometries and harmonic vibrational frequencies of dibenzofuran in the ground and lowest triplet state have been calculated using the Hartree-Fock and Becke-3-Lee-Yang-Parr(B3LYP)density functional methods with the 6-31G basis set. Upon the excitation to the lowest triplet state, the molecular structure retains the planar form but distorts from a benzene-like to a quinone-like form in skeleton. Scaled vibrational frequencies for the ground and lowest triplet state obtained from the B3LYP calculation show excellent agreement with the available experimental data. A few vibrational fundamentals for both states are newly assigned based on the B3LYP results.

작품리뷰 - 과천뒷골감나무집

이상연,Lee, Sang-Yeon 대한건축사협회 2000 建築士 Vol.2000 No.4

국내 일반전자부품산업의 현황 및 발전과제

이상연,Lee, Sang-Yeon 한국전자정보통신산업진흥회 1997 電子振興 Vol.17 No.11