이중 증기 통로를 가진 히트파이프의 작동유체 평가

전철호,장영석,김오근,노인창 동아대학교 생산기술연구소 2000 生産技術硏究所硏究論文集 Vol.5 No.1

The evaluation of heat transport within a heat pipe with double vapor path and working fluid of different kinds were experimental investigated. Experiments carried out with acetone/ethanol, ethanol/ethanol, etc heat pipe of various with aluminium container of two way vapor path. Performance measurements can be operated at high levels , over 27000 w/㎡ heat flux at 100mm long evaporator. The constitute of 2 way vapor heat pipe was enough to apply the vast range working. In this study, reliable basic data obtained by testes in the 2 way vapor path heat pipe can be used for thermal design, manufacture, production etc.

Duplex처리 의한 TiN 표면코팅 한 H13강의 특성

전철호,옥철호 東亞大學交附設 生産技術硏究所 2005 生産技術硏究所硏究論文集 Vol.10 No.-

A duplex surface treatment technique based on plasma nitriding and TiN coating was developed to improve the wear resistance and fatigue properties of mould steel for severe environment. The duplex treatment of plasma nitriding and TiN coating was performed on AISI H13 steels. TiN thin films were deposited on AISI H13 steel substrates by DC magnetron sputtering. The properties of the duplex treatment were compared with normally treated TiN coating. The process conditions of TiN coating for AISI H13 steel are working temperature of 530℃ and treatment times of 6hr, 12hr and 24hr. volume ratios of Ar : N_(2) was 3/2(Ar : N_(2)=3:2). The base pressure and working pressure was 7.4 x 10^(-4) Pa, and 2.6 x 10^(-1) pa, respectively. Effects of the duplex treatment on surface characteristics of AISI H13 have been investigated using micro-hardness tester, scanning electron microscope(SEM) and scratch tester. Microstructure and phase analysis were performed using SEM and X-ray Diffraction Analysis(XRD). The results of duplex treatment were excellent in terms of mechanical properties when they were compared with the conventional TiN coating.

韓國 交通政策의 現在 및 未來課題 : 鐵道經營 政策方向을 中心으로 On the Perspective Policy in Railroad Business

全哲鎬 大田産業大學校 1994 한밭대학교 논문집 Vol.11 No.0102

This study focuses on the question why the present and future transportation market structure is needed. Especially in preparation for the new government-railway relationship and the expected necessity of intermediate/long-term planned active railway business in the coming era of rapid-transit electronic railway, the future comparative advantage of railway compared with other transportation(especially land transportation) must be examined in order to boost persistent and spontaneous railroad Policy and Propose reform measures curing the chronic railroad business deficit. As reference for the improvement of Korean railway business, particular railway business policies in other countries are reviewed. The result and the main point of railway business policy in this study are as follows: (ⅰ) to establish the partial responsibility system of investors and funds towards the public and profit sectors : (ⅱ) to propose the deregulation of railway rate system and the internal business policy(especially the improved railway parcel system and the reduced personal expenditures) as the means for the establishment of the profit-oriented system assuring the profit of railway business.

兼業銀行制度下에서의 流動性管理에 관한 諸學說 比較 硏究

全哲鎬 大田産業大學校 1996 한밭대학교 논문집 Vol.13 No.1

우리나라의 銀行들은 WTO體制下의 資本市場 開放化에 즈음하여 지금까지의 專門銀行制度에서 世界的 인 變形 趨勢인 兼業銀行制度로 本格的인 銀行經營의 多角化 過程을 目前에 두고 있으며, 이에 대비한 諸 銀行經營原則 中 가장 重視되는 部分이 流動性確保策이며, 또한 諸 學者들의 論爭 초점 대상이다. 流動性管理가 重視되는 이유는 銀行들이 수행해야 될 經營目的中 '預金者의 保護側面'外에도 近年에 强調되고 있는 '銀行의 收輦性確保라는 두가지 상반된 目的의 衝突로서 어떻게 이 兩者를 合 目的으로 調和를 導出해 낼 수 있는가의 結論을 내리l기 위해서는 兼業鑛行制度의 대표격인 獨逸을 中心으로 提示되고 있는 諸 學說의 代表的인 세 理論으로서 먼저 Hu¨bner가 19世紀 중반에 제창한 銀行經營의 流動性 確保原則인 Goldene Bankregel(銀行鐵則論), Wagner의 主唱論인 Bodensatztheorie(沈積論) 및 Stu¨tzel 敎授의 Maximalbelastungstheorie(最大負債論)등을 相互批判·分析하여 流動性管理에 客觀的인 指針을 마련하였음.

SiO₂ Wick을 使用한 Heat Pipe의 傳熱特性에 관한 硏究

全哲昊,徐海成 동아대학교 공과대학 부설 한국자원개발연구소 1985 硏究報告 Vol.9 No.1

Cu heat pipe with SiO₂ sintered wicks type capillary structure and distilled water as the working fluid was studied in the heat transfer rate range of 60W to 180W. Analysis resistances are considered in the pipe wall at the condenser and evaporator, in the fluid gap between pipe wall and capillary structure, at liquid vapor interface, and in the vapor region. The results are as follows. 1) Thermal resistance of wick had larger than any other thermal resistance and thermal resistance at pipe wall, interface, vapor region can usually be neglected 2) Increase the heat transfer rate and vapor temperature, temperature difference of evaporator were increased but temperature difference of vapor path were not changed.

복합사이클 발전소의 효율에 관한 연구

전철호,장길홍 동아대학교 공과대학 부설 한국자원개발연구소 1993 硏究報告 Vol.17 No.2

The use of a combined cycle leads to an updating of power output, at the same time, increasing power plant efficiency. In this paper, the dissipation energy was calculated from two conventional and combined cycle processes, and then the efficiencies of many types of the combined cycle were compared. The efficiency of combined cycle power plant is evaluated by given data and its performance characteristics from the simulation. As a result, the total efficiency is increased as the compression ratio is increased.

이온 펌프 성능평가를 위한 돔(dome) 설계

전철호,박종윤,임종연 한국진공학회 2000 한국진공학회 학술발표회초록집 Vol.- No.-

Transition Metal-Catalyzed Ortho-Functionalization in Organic Synthesis

전철호,박영준 대한화학회 2005 Bulletin of the Korean Chemical Society Vol.26 No.6

Recent progress in the filed of transition-metal mediated C-H bond activation has had a great influence on organic synthesis. Among such transition-metal catalyzed reactions, ortho-functionalization via the chelation-assisted strategy has been paid great attentions as one of the powerful methodologies for converting aromatic compounds into ones that are more functionalized at the exclusively ortho-position. In this context, various transition metal-catalyzed ortho-functionalizations such as alkylation, alkenylation, silylation and carbonylation are described briefly and their prospects are suggested.

다양한 요구사항 수용 및 데이터 조회 성능 향상을 위한 CQRS 패턴 기반의 사물인터넷 플랫폼 설계

전철호,전현식,박현주,Jeon, Cheol-Ho,Jeon, Hyeon-Sig,Park, Hyun-Ju 한국정보통신학회 2020 한국정보통신학회논문지 Vol.24 No.11

현대 사회의 과학기술 발전으로 유비쿼터스 시대가 도래함에 따라 사회적으로 사물인터넷 환경에서 발생하는 데이터에 관한 관심이 증가하였다. 하지만 기존 사물인터넷 플랫폼은 대용량 데이터에 대한 통계 처리와 같이 많은 처리량을 요구하는 조회 요청 처리에 어려움이 있다. 이에 따라 본 논문에서는 조회 요청에 대한 요구사항을 유연하게 수용할 수 있고 조회 성능을 향상 시킬 수 있는 사물인터넷 플랫폼을 제안한다. 본 논문에서 제안하는 플랫폼은 별도의 읽기 데이터베이스를 도입하여 평균 응답시간 측면에서 약 1200배의 성능 향상을 보였으며, 객체 모델을 명령 사이드와 조회 사이드로 분리함으로써 객체의 복잡도를 낮춰 플랫폼에 대한 다양한 요구사항을 빠르게 수용할 수 있도록 하였다. With the advent of the ubiquitous era due to the development of science and technology in the modern society, interest in data generated in the IoT environment has increased socially. However, the existing IoT platform has difficulties in processing inquiry requests that require large amounts of throughput, such as statistical processing of large amounts of data. Accordingly, in this paper, we propose an IoT platform that can flexibly accommodate requirements for inquiry requests and improve inquiry performance. The platform proposed in this paper showed a performance improvement of about 1200 times in terms of average response time by introducing a separate read database. By separating the object model into a command side and a query side, the complexity of the object is reduced to meet the various demands on the platform. It was made to allow quick acceptance of the matter.

실외 온도 변화에 따른HC계 공랭식 히트펌프 시스템의 성능 특성

전철호,이호생,김재돌,윤정인 대한설비공학회 2006 설비공학 논문집 Vol.18 No.3

The performance of an air to water vapor compression heat pump has been investigated experimentally. The main purpose of this study was to study the possibilities of using hydrocarbon refrigerants as a working fluid to replace R-22 for vapor compression heat pumps. Pure R-22 and R-290, R-600a, R-1270 were considered as working fluids. The performance of the system was characterized by compression shaft work, refrigeration capacity, pressure ratio, discharge temperature and COP. The experimental apparatus has basic parts of cycle that uses the air as a heat source. The experimental results show that refrigeration capacity of HC refrigerants is same or higher than that of R-22. On the other hand, compression shaft work of HC refrigerants is lower than that of R-22. Compression shaft work is lower than that of R-22. Come to the conclusion that, it is possible that hydrocarbon refrigerants could be drop-in alternatives for R-22.