스마트 농업용 멀티드론 시스템 개발: 진행 현황

박영주,이현진,주찬영,손형일,Park, Youngju,Lee, Hyunjin,Ju, Chanyoung,Son, Hyoung Il 한국교통대학교 융복합기술연구소 2016 융ㆍ복합기술연구소 논문집 Vol.6 No.1

In this paper, we report a work-in-progress about development of multi-drone system for smart agriculture. The multi-drone system is controlled via a haptic teleoperation by a human operator. The purpose of the multi-drone system is that let the human operator to easily handle the multiple drones which are maintaining a fixed formation using ZigBee communication network.

알루미늄 6061 합금의 양극 산화 인가 전압과 시간에 따른 표면의 산화피막층 형성 거동

박영주,정찬영,Park, Youngju,Jeong, Chanyoung 한국전기전자재료학회 2021 전기전자재료학회논문지 Vol.34 No.1

Aluminum is a lightweight metal and has excellent properties with regard to conductivity, workability, and strength. It has been used in various industries owing to its economic benefits. To improve upon the mechanical properties and processability by adding various alloying elements to aluminum, improving the corrosion resistance and heat resistance by electrochemically forming a porous anodic film having a thickness and hardness on the surface of the aluminum alloy is crucial. In this study, the aluminum 6061 alloy was controlled by an anodization process in a 0.3M oxalic acid electrolyte at room temperature to investigate the oxide film parameters such as porosity and thickness depending on the modulating applied voltage and time. The anodizing experiment was performed by increasing the time from 1 h to 9 h at 2-h intervals at applied voltages of 50 V and 60 V.

건축용 바닥재의 외부복사열에 의한 화재위험성 비교 연구

박영주,김영탁,Park, Youngju,Kim, Youngtak 한국안전학회 2017 한국안전학회지 Vol.32 No.5

In this study, we have performed the Cone Calorimeter test in accordance with ISO 5660-1 to check the combustion characteristics of building flooring materials. The fire risk of these materials were evaluated by construction code, KFI criteria and standards of flame retardant performance. When samples exposed to external heat flux, all samples consumed a lot of Oxygen for a long time. So heat release from sample burning continued so long. And also all samples produced so much smoke. Even though a few samples were satisfied with only peak heat release rate criteria, all 8 samples were not satisfied with criteria of peak heat release rate and total heat released together. The results of 5 min total heat released were $15.9MJ/m^2{\sim}5.9MJ/m^2$. It menas the results are more than 2~6 times higher than the criteria. The results of 10 min total heat released were $30.1MJ/m^2{\sim}100.8MJ/m^2$. It means the results are more than 3~12 times higher than the criteria. 6 of 8 samples were not satisfied with Dm.corr.(corrected maximum smoke density) criteria. The building flooring materials which we used for this test ignited very fast and the burning continued so long. It means these samples are susceptible to fire.

화재사례를 통한 미소화원의 감정기법에 관한 실험적 연구: 촉진제 유무에 따른 화염높이를 중심으로

박영주(Park Youngju) 한국방재학회 2018 한국방재학회논문집 Vol.18 No.6

In order to verify the flame heights of tiny fire sources, this study analyzed the height of the flame in the fire ignited in an ashtray. In this regard, the values measured in a reproduction experiment were compared with the mean flame height, as suggested by Heskestad and are applicable in the range of turbulence of spontaneous fire. For the reproduction experiment, flammable liquids (ethyl alcohol and gasoline) and combustibles (absorbent cotton and cigarette butt) were put into the ashtray as variables. As a result and as per the Heskestad formula, the height of the flame was 0.8 m when there was only a cigarette butt, and it was 3.43 m when a flammable liquid was included. In conclusion, the fire reproduction experiment showed that only a cigarette butt and the flammable liquid were the individual variables, with large differences in the height of the flame. 본 연구에서는 미소화원의 화염높이 검증을 위해 발화원인이 재떨이로 추정된 화재에 대하여 화염높이를 분석하였다. 재떨이로부터의 화염높이 분석은 재현실험에서의 측정한 값과 자연화재의 난류범위 안에 적용될 수 있는 Heskestad가 제안한 평균 화염높이를 계산한 값을 분석하였다. 재현실험은 재떨이 내에 인화성액체(에틸알콜, 휘발유)와 가연물(솜, 담배꽁초)을 각각 투입하여 변수로 하였다. 연구 결과, Heskestad식의 경우는 담배꽁초만 있는 경우 화염의 높이는 0.8 m, 인화성액체(휘발유)가 포함된 경우에는 3.43 m로 계산되었다. 재현실험 결과는 담배꽁초와 가연성 액체의 경우 화염 높이는 변수별 큰 차이가 있음을 확인할 수 있었다.

철도차량용 시트커버의 화재안전에 관한 연구

박영주(Park, Youngju) 한국방재학회 2018 한국방재학회논문집 Vol.18 No.5

본 연구에서는 철도차량에 실제 사용되고 있는 철도차량용 시트커버의 화재안전성을 확인하기 위해 국제규격인 ISO 5660-1을 따라 시험분석을 수행하였다. 시험을 실시한 총 16개의 시험샘플 모두 철도차량 기술기준에서 정하고 있는 최대평균열방출률 기준을 만족하는 것으로 나타났다. 하지만, 연기발생데이터의 경우 샘플의 질량감소율에 따른 연기발생량이 샘플별로 큰 차이를 보였다. 철도차량기술기준에서는 연기발생의 경우 ISO 5660-1 시험방법이 아닌 ASTM E662 시험방법으로 별도로 수행하고 있다. 두 시험방법의 결과는 서로 상관관계가 있는 것으로 밝혀져 있으므로, 하나의 샘플에 대해서 한 번의 시험분석으로 열방출률과 연기발생량을 측정하여 평가할 수 있다면 좀 더 효율적이고, 정확한 시험평가가 이루어질 수 있을 거라 판단된다. In this study, we performed the Cone Calorimeter test in accordance with ISO 5660-1 to verify the fire safety of seat covers in railway vehicles. All 16 samples that were tested satisfied the MARHE criteria. However, we found that there was a big difference in smoke production data from the mass loss for each sample. The ASTM E662 standard was used to evaluate the smoke production of these railway vehicle materials. There was a correlation between the ISO5660-1 test results and the ASTM E662 test results. If we use two different types of data at the same time in one test, heat release, and smoke production, we can evaluate fire safety correctly and effectively for these samples.

정족수 억제균 직접 주입이 거품 발생과 막오염 제어에 미치는 영향

박영주 ( Youngju Park ),박현아 ( Hyeona Park ),김진우 ( Jinwoo Kim ),추광호 ( Kwang-ho Choo ) 한국물환경학회 2024 한국물환경학회·대한상하수도학회 공동 춘계학술발표회 Vol.2024 No.-

스테인리스 스틸의 표면 산화피막 성장과 내부식성 상관관계

박영주 ( Youngju Park ),유진석 ( Jinseok Yu ),심성구 ( Seong Gu Sim ),정찬영 ( Chanyoung Jeong ) 한국부식방식학회(구 한국부식학회) 2021 Corrosion Science and Technology Vol.20 No.3

Stainless steel is a metal that does not generate rust. Due to its excellent workability, economic feasibility, and corrosion resistance, it is used in various industrial fields such as ships, piping, nuclear power, and machinery. However, stainless steel is vulnerable to corrosion in harsh environments. To solve this problem, its corrosion resistance could be improved by electrochemically forming an anodized film on its surface. In this study, 316L stainless steel was anodized at room temperature with ethylene glycol-based 0.1 M NH₄F and 0.1M H₂O electrolyte to adjust the thickness of the oxide film using different anodic oxidation voltages (30 V, 50 V, and 70 V) with time control. The anodic oxidation experiment was performed by increasing the time from 1 hour to 7 hours at 2-hour intervals. Corrosion resistance according to the thickness of the anodic oxide film was observed. Electrochemical corrosion behavior of oxide films was investigated through polarization experiments.

교원양성기관으로서 교육대학원의 역할과 의미 탐색에 관한 연구 : A대학교 교육대학원생의 학교생활 경험을 중심으로

박영주(Park, Youngju),조진한(Cho, Jinhan),김병찬(Kim, Byeongchan) 한국교육행정학회 2018 敎育行政學硏究 Vol.36 No.3

본 연구는 교육대학원생의 학교생활 경험, 즉 수업과 수업 외 경험을 살펴보고 교육대학원의 실질적인 기능이 되고 있는 교원양성기관으로서의 역할과 그 의미를 심도 있게 탐색하고자 하였다. 이에, 서울시 소재 A대학교 교육대학원에서 수학하고 있는 교육대학원생들을 대상으로 수업 참여관찰과 심층면담을 중심으로 한 질적 사례연구를 진행하였다. 연구결과, 학생들의 수업 경험으로는 ‘학부와 다를 것 없는 수업’, ‘노하우만 전수받는 수업’이 되고 있어 전반적으로 “기대가 없는 수업” 경험을 하고 있는 것으로 나타났다. 또한 수업 외 경험으로는 ‘교육봉사는 새로운 지도교수’, ‘대학원은 사교육의 연결고리’라는 것을 통해 “그렇게 교사가 된다”는 것을 알 수 있었다. 이러한 결과를 종합해볼 때 교육대학원이 가지는 역할과 의미는 교육대학원생들이 교사가 되어가는 과정으로서 전문성과 정체성을 함양시킬 수 있는 수업과 수업 외 프로그램을 제공해야 한다는 것이다. 먼저, 전문성 함양을 위해 교수에게 일방적으로 지식이나 노하우를 전달받는 것에서 벗어나 활발한 상호탐구 과정이 일어날 수 있도록 배움의 공동체로서의 경험을 제공해야 한다. 또한 단순한 교수학습 테크닉을 뛰어넘어 배움의 탐구 과정을 경험하는 수업을 제공해야 한다. 다음으로 정체성 함양을 위해서는 양질의 교육봉사가 될 수 있도록 체계적인 지원 시스템이 구축되어야 하며, 임용고시를 위한 지원체계에서 벗어나 활발한 배움과 논의가 이루어질 수 있는 장을 형성하여 예비교사로서 성장해나갈 수 있도록 조력해야 한다. This study was conducted to research education graduate school’s purpose, meaning and its function as teacher training institution, from graduate students’ curricular and extracurricular experience. Qualitative case study was conducted on students at ‘A’ university in Seoul by class observations and in depth interview. As a result of the case study, students were only experiencing ‘Nothing to expect’ kind of classes because they felt the classes were ‘Nothing difference between bachelors degree program’, or ’Only passing down practical experience’. From their extracurricular experience, through ‘Educational community service is new teacher’, ‘Masters program is connection between private education’, they found out that ‘They become teachers that way’. According to the results, Master’s degree program for education’s purpose and meaning is to provide curriculums and extracurricular programs to develop student’s expertise and identity while students are on their way to become a teacher. First, to develop student’s expertise, program should provide active interactive classes between student and the professor, differ from one-sided learning experience only from the professor. For developing identities, well-developed educational system has to be established to lead students to provide quality community services. This system also should provide places for interactive learning experience and discussion between professors, differing from educational system that only preparing them for their teacher licensure exam, so that they grow as teachers of future.

건축용 실내 인테리어 소재의 화재위험성에 관한 연구

박영주(Park, Youngju),김영탁(Kim, Youngtak),이해평(Lee, Haepyeong) 한국방재학회 2017 한국방재학회논문집 Vol.17 No.3

본 연구에서는 건축용 실내 인테리어 제품들에 대한 연소특성을 파악하기 위해 ISO5660-1에 따라 콘칼로리미터 시험을 수행하였다. 건축법 및 KFI 인정기준에서 제시하고 있는 성능기준과 비교를 통해 시중에 유통⋅판매되는 제품의 화재위험성을 평가하였다. 시험을 수행한 12개의 제품 중 4개는 최대열방출률과 총열방출량에서 모두 기준을 만족하였으나, 8개의 제품은 기준을 만족하지 못하는 것으로 나타났다. 또한 플래쉬오버성향 분석 결과도 총 12개의 재료 중 6개가 중간(Intermediate), 2개가 높음(High)으로 나타났다. In this study, we have peformed the Cone Calorimeter test in accordance with ISO5660-1 to check the combustion characteristics of building interior materials. The fire risk of these materials were evaluated by construction code and KFI criteria. 4 samples of 12 were satisfied with criteria of peak heat release and total heat released but 8 of 12 weren’t satisfied with criteria. The flashover propensity of 6 of 12 samples were “Intermediate” and 2 of 12 samples were “High.”

내식성 향상을 위한 기능성 타이타늄 표면 개질

박영주 ( Youngju Park ),정찬영 ( Chanyoung Jeong ) 한국부식방식학회 2021 Corrosion Science and Technology Vol.20 No.5

Titanium is applied in various industries due to its valuable properties and abundant reserves. Generally, if a highly uniform oxide structure and a high-density oxide film is formed on the surface through anodization treatment, the utility value such as color appearance and corrosion inhibition efficiency is further increased. The objective of this study was to determine improvement of water-repellent property by controlling titanium oxide parameters such as pore size and inter-pore distance to improve corrosion resistance. Oxide film structures of different shapes were prepared by controlling the anodization processing time and voltage. These oxide structures were then analyzed using a Field Emission Scanning Electron Microscope (FE-SEM). Afterwards, a Self-Assembled Monolayer (SAM) coating was performed for the oxide structure. The contact angle was measured to determine the relationship between the shape of the oxide film and the water-repellency. The smaller the solid fraction of the surface, the higher the waterrepellent effect. The surface with excellent hydrophobic properties showed improved corrosion resistance. Such water-repellent surface has various applications. It is not only useful for corrosion prevention, but also useful for self-cleaning. In addition, a hydrophobic titanium may open up a new world of biomaterials to remove bacteria from the surface.