노통 연관식 폐열 보일러의 최적 설계

박이동,이관종,장영근 成均館大學校 科學技術硏究所 1995 論文集 Vol.46 No.2

This study is to obtain optimized design parameters of waste heat boiler with fire and smoke tube which are widely used to provide process and building heat. The optimum parameters obtained in this study can be used as a guideline for actual. boiler design of this type. The design optimization considered here is to find the most economical dimensions of the boiler considered which results in a minimum cost in producing a unit amount of steam per given period of operation. For this purpose, the first we have to determine what are the main parameters of affecting the total cost of producing a unit amount of steam which is comprised of manufacturing cost of the boiler, operating cost of the fan, etc. For the selected design parameters, we will have to decide the conditions of each parameter which will result in the minimum total cost. For the waste heat boiler with fire and smoke tube under consideration, the major parameters of affecting the total cost are considered to the diameter of the smoke tube and the gas velocity among others. The two parameters selected here are considered for finding the optimum size of the boiler by minimizing the total cost which is a function of the manufacturing cost, purchasing cost of the fan, and the operation cost of the system. Through computer simulation, the optimum conditions of these two parameters are obtained for different boiler capacities and different periods of operation.

非品質半導體 As-Ge-Se系의 光構造變化

이종록,梁成伊 梨花女子大學校 韓國生活科學硏究院 1990 韓國生活科學硏究院 論叢 Vol.45 No.-

The photostructure of amophous semiconductor AsGeSe_x for which X concentrations are 52.2, 55.6, 63.6, 79 at.% is investigated. The thin film samples are prepared by the thermal evaporation method. The thin films which are illuminated and annealed are mesured with X-ray diffration and SEM(scanning electron microscopy). When the thin films are illuminated and annealed, the absorption coefficients are increased and the band gap energies are decreased. From the experimental results photodarkening and thermaldarkening were confirmed. It is photodarkening and thermaldarkening that the absorption coefficient is increased and the band gap energy is decreased when the amorphous semiconductor is illuminated and materials increase, then the absorption edge shifts toward the long wavelength. From the SEM the amorphous thin films which are illuminated and annealed are separated into two different phases. The thin films which are illuminated look like the wave shape. This is the spinodal phase separation. The thin films which are annealed look like the globlar shape. This is the binodal phase separation.

태양열 온수의 효과적 이용에 관한 시뮬레이션

박이동,정운철,임종오 成均館大學校 科學技術硏究所 1992 論文集 Vol.42 No.2

The benefits of thermal stratification in sensible heat storage systems have been considered and studying by several investigators. In this paper, the basic data which is hard to obtain normally through experiments were obtainable through the computer simulation. The major objectives of the study were to assess the benefits of stratified storage in residential solar water heating application and to suggest the optimum design parameters. From the above computer simulation, following results were obtained. 1) The solar load fraction increases with increasing the number of tank segments. In these simulation, the magnitude of the improvement was about 10%. 2) The solar load fraction increases when the ratio of diameter to height of the tank(H/D) increases to 3, but H/D exceed 3 then, the solar load fraction decreases. In these simulation, the magnitude of the improvement was about 3 %. 3) Increasing the collector flow rate slightly improved the performance of the mixed storage system (Node = 1). Also, for the stratified storage system(Node = N), the solar load fraction increases with decreasing flow rate until the point is reached at which the collector outlet temperature reaches the boiloff limit of 100℃ over some portion of the simulation period.

현대 무도(武道)의 지향과제에 대한 논의

최종균,장재이,홍장표,박순진,김의영 龍仁大學校 武道硏究所 1999 武道硏究所誌 Vol.10 No.1

I would like to make the following suggestions on the basis of such problems as arguments over the philosophies and historicity of modern martial arts, a flood of groups with commercialism, the absence of true martial arts in the wake of game-oriented trends, and the stagnation of martial arts. First, the philosophy and historicity of martial arts should be established. I should like to suggest that the philosophy of martial arts should be established through the understanding of the changing aspect of the Eastern cultures and changes in the meanings of martial arts. Second, the groups of martial arts should be fostered in a synthetic fashion. Third, the methods of running martial-art games should be improved. That is, it is necessary that the games should be improved in order to activate the essence of martial arts. Fourth, martial arts should be made academic. Philosophy, science and Comtism should be organically connected so that martial arts may be academically systemized.

Acinetobacter sp. BE-254에 의한 유화제의 생산

김순한,임이종,최경숙,정영기,장경립,이태호 한국미생물생명공학회 ( 구 한국산업미생물학회 ) 1996 한국미생물·생명공학회지 Vol.24 No.2

Bioemulsifier를 생산하는 미생물을 토양으로부터 screening하였다. 그 중에서 유화활성과 유화안정성에서 가장 우수한 BE-254 균주를 순수분리하여 동정한 결과, Acinetobacter속으로 판명되었다. Bioemulsifier 생산을 위한 최적배지 조성은 n-hexadecane 4%, NaNO_3 0.2%, KH_2PO_4 0.05%, MgSO_4·7H_2O 0.05%, CaCl_2 0.01%, yeast extract 0.01%이였으며, 최적온도와 pH는 각각 30℃와 7.0이였다. 이러한 조건에서 500㎖용 shaking flask에 최적배지 50㎖를 넣어 배양했을 경우 대수증식기 말기인 5일째 균의 증식과 유화활성이 가장 높게 나타남에 따라 Acinetobacter sp. BE-254에 의한 bioemulsifier의 생산은 균의 생육과 밀접한 관련이 있는 것으로 판단되었다. 유화기질로서 hydrocarbon류, edible oil류, 그리고 petroleum fraction등에 작용시켰을 경우 이들 물질에 대해서 비교적 높은 활성을 나타내어 유화제 로서의 우수성을 시사 하였다. The strain producing bioemulsifier was isolated from soil samples. The isolated strain was identified as the genus Acinetobacter through its morphological, cultural and physiological characteristics. The highest emulsification activity and stability by Acinetobacter sp. BE-254 was observed after 5 days of cultivation in the culture medium containing n-hexadecane 4%, NaNO_3 0.2%, KH_2PO_4 0.01%, MgSO_4·7H_2O 0.01%, CaCl_2 0.01% and yeast extract 0.01%. The optimum pH and temperature for bioemulsifier production were pH 7.0 and 30℃, respectively. Furthermore the most of bioemulsifier was produced during the exponential growth phase, and this suggested that the bioemulsifier production was growth-associated. The bioemulsifier showed good emulsification activity on various emulsifying substrates such as hydrocarbons, edible oils, and petroeum fractions.

Acinetobacter sp. BE-254에 의한 유화제의 생산

최경숙,장경립,임이종,김순한,정영기,이태호 동의대학교 기초과학연구소 1997 基礎科學硏究論文集 Vol.7 No.1

The strain producing bioemulsifier was isolated from soil samples. The isolated strain was identified as the genus Acinetobacter through its morphological, cultural and physiological characteristics. The highest emulsification activity and stability by Acinetobacter sp. BE-254 was observed after 5 days of cultivation in the culture medium containing n-hexadecane 4%, NaNO₃0.2%, KH₂PO₄0.01%, MgSO₄·7H₂O 0.01%, CaCl₂0.01%, and yeast extract 0.01%. The optimum pH and temperature for bioemulsifier production were pH 7.0 and 30℃, respectively. Furthermore the most of bioemulsifier was produced during the exponential growth phase, and this suggested that the bioemulsifier production was growth-associated. The bioemulsifier showed good emulsification activity on various emulsifying substrates such as hydrocarbons, edible oils, and petroleum fractions.

全北, 母옮山의 植物資源에 관한調査冊究

ee,Jong Suk,Bae,Jong Hyang,Yoo,Sung Oh 한국화훼산업육성협회 1993 화훼연구 Vol.2 No.2

Effect of microstructure on the tribological properties of apatite-wollastonite glass ceramic

Jong-Ee Park,Abdullah Öztürk,Sang-Hee You,Sam-Sik Park,배원태,신동우 한양대학교 세라믹연구소 2008 Journal of Ceramic Processing Research Vol.9 No.3

A relationship between microstructure and the tribological properties of Apatite-Wollastonite glass ceramics (A-W GC), fabricated by different techniques of melt casting and powder packing processing, was studied. The surface crystallization of wollastonite caused a unique surface strengthening in an A-W GC prepared by the melt casting process. The wear rate did not vary between the free surface and interior in an A-W GC made by the powder packing process, whereas an increase of the wear rate with an increase in the distance from the free surface was detected in an A-W GC fabricated by the melt casting process. However, the melt casting process resulted in a higher wear resistance in an A-W glass ceramics for prosthetic applications.

Inhibitory effects of Angelicae Gigantis Radix on osteoclast formation

Kil, Jong-Seob,Kim, Myung-Gyou,Choi, Hye Mi,Lim, Jong-Pil,Boo, Yungmin,Kim, Ee-Hwa,Kim, Jeung-Beum,Kim, Hye Kyung,Leem, Kang-Hyun John Wiley Sons, Ltd. 2008 Phytotherapy research Vol.22 No.4

<P>Angelicae Gigantis Radix (AGR) is one of the most widely used herbal medications. AGR is the dried root of Angelica gigas Nakai (Umbelliferae), which is known as Korean angelica. This study investigated the effects of AGR on osteoclast formation using primary bone marrow cells. TNF-&agr; treatment increased tartrate-resistant acid phosphatase (Trap) positive cells and Trap activity in bone marrow cells. However, AGR significantly decreased both TNF-&agr;-induced Trap positive cells and Trap activity. RT-PCR analyses revealed that AGR decreased mRNA levels of Trap and matrix metalloproteinase-9 in TNF-&agr;-treated bone marrow cells. In addition, AGR decreased TNF-&agr;-induced activation of NF-&kgr;B. These results suggest that AGR has an inhibitory effect on the formation of osteoclasts and its effect is partially related to the NF-&kgr;B pathway. Copyright © 2008 John Wiley & Sons, Ltd.</P>

30Nm³/h급 합성가스 초고순도 정제시스템 개발 현황

이승종(Seung Jong 1ee),윤덕규(Deok-Kyu Youn),김혜수(Hye Soo Kim),이철호(Chul-ho Lee),이재영(Jae Young Lee),김미정(Mi Jeong Kim) 한국환경에너지공학회 2022 한국열환경공학회 학술대회지 Vol.2022 No.2

합성가스 기반 수소생산 기술은 석유 코크스, 석탄, 폐기물 동의 저급자원을 가스화하여 합성가스를 생산하고 이를 정제, 전환 및 분리하여 수소를 생산하는 기술로, 원유 정제 후 남는 부산물인 석유 코크스롤 가스화하여 수소를 생산하기 위한 일환으로 기 술개발을 수행하고 있다. 석유 코크스를 이용하여 안정적으로 수소를 생산하기 위해서는 가스화룔 통해 생산된 합성가스에 함유된 H2S, COS, NHa 둥과 같은 산성가스 및 염기성 가스를 0.1 ppm 이하로 제거하는 초고순도 정제가 필요하다. 본 연구팀에서는 석유 코크스 가스화를 통해 수백~수천 ppm으로 발생되는 H2S와 COS를 제거하는 설비와 수~수십 ppm 이 하로 발생되는 NH3 동의 미 량가스몰 제거하는 30Nm³/h 규모의 설비를 설계하였으며, 석유 코크스 가스화를 통해 생산된 합성가스를 초고순도로 정제하기 위한 시스템을 구축하여 운전 중에 있다.