1Cr-0.5Mo 강 용접부 균열의 고온파괴거동 연구

이해무,윤기봉,신규인,최현창,박재학 한국산업안전학회 1997 한국안전학회지 Vol.12 No.2

Fracture behavior of ex-serviced 1Cr-0.5Mo steel was measured at room(24℃) and elevated(538℃) temperature and compared with that measured with virgin 1Cr-0.5Mo steel. Compact C(T) specimens were machined from the base and welded test materials. In case of the C(T) specimens of the weld, fatigue precrack was introduced along the fusion line so that following crack growth should occurs along the region of heat affected zone. It was observed that the J-R curve of the serviced material was significantly lower than that of the virgin material at room temperature. Brittle fracture was observed in the serviced material. On the other hand, at elevated temperature no noticeable difference was found between the J-R curves of the virgin and the serviced material. The measured J-R curves were also compared with those of the 1.25Cr-0.5Mo steel obtained from the other literatures. Optical microscopy and SEM examination of the serviced material reveal the carbide in/along the grain boundary which shows material degradation due to long-term usage. An example of application of the measured J-R curves is shown.

고로내와 류이한 조건하에서 알칼리 금속이 산화철의 환원반응과 코우크스의 가스화 반응에 미치는 영향

윤종규,조남교 대한금속재료학회(대한금속학회) 1983 대한금속·재료학회지 Vol.21 No.10

Among the mechanism and kinetics of iron oxide reduction and coke gasification reaction reported, only the reactions under isothermal condition or iso-gas compositions are reported. Very few papers are published concerning non-isothermal reactions. In this papers, experiments for the reduction of wustite along with the coke gasification were performed under the simulated conditions of thermal reserve zone of iron blast furnace which is apparently non - isothermal and non iso-gas composition. The main object of this research is to probe the rate and effect of alkaline metal additions on the wustite reduction and coke gasification. Temperature and gas compositions are varied to simulate the running conditions of old type and modern type blast furnace. Gas utilization factor is introduced to explain the abundancy or the shortage of the reducing gases in the blast furnace running conditions.

한국산 하루살이목(目)의 카탈로그

윤일병,배연재,전동준 고려대학교 한국곤충연구소 1994 昆蟲硏究誌 Vol.20 No.1

韓國産 하루살이目의 카탈로그. 裵淵宰 · 尹一炳^1 · 田東埈^2 (서울女子大學校, ^1高麗大學校 生物學科, ^2러시아科學院 動物學硏究所) 昆蟲硏究誌, 20: 31~50, 1994. 韓國産 하루살이目의 關한 硏究는 南北韓에 걸친 綜合的인 硏究가 이루어지지 못하였고, 1940년 以來 各種 文獻에 記錄된 種들에 있어서도 分類上 혹은 命名上 變動이 많았으나 이를 體系的으로 收錄하지 못하였다. 이 論文에서는 種合的인 文獻 및 模式標本 調査를 통하여 다음과 같이 韓國産으로 記錄된 56種의 命名상 有效한 種들에 대한 카탈로그를 작성하였다. Acerella longicaudata(U′eno), *Ameletus costalis (Matsumura), A. montanus Imanishi, *Baetiella japonica (Imanishi), *B, tuberculata (Kazlauskas), *Baetis thermicus U′eno, Bleptus fasciatus Eation, Choroterpes altioculus Kluge, Cincticostella castanea (Allen), C. tshernovae(Bajkova), * Cinygmula grandifaliz Tshernova, *C. hirasana (Imanisht), Cloeon dipterum (Linnaeus), Drunella aculea (Allen), *D. cryptomeria (Imanishi), *D. lepnevae (Tshernova), D. triacantha (Tsher-nova), *D. trispina ezoensis (Gose), Ecdyonurus bajrovae Kluge, E. dracon Kluge, **E. Joernensis mon-golicus Bajkova & Varychanova, E. kibunensis Imanishi, E. levis (Nava′s), E. scalaris Kluge, **E. subspinosa (Braasch & Solda′n), Epeorus curvatulus Matsumura, *E. hiemalis Imanishi, E. latifolium Ue′no, E. pellucidus (Broadsky), *Ephemeralla aurivillii Bengtsson, *E. imanishii Gose, E. keijoensis Allen, *E. notofascia Yoon & Base, Ephemera orientalis McLachlan, E. separigata Bae, E. strigata Eaton, Ephoron shigae (Takahashi), Heptagenia guranica Belov, H. kihada Matsumura, *H. Kyotoensis Gose, *Iron aesculus (Imanishi), *I. koreanicus Braasch & Solda′n, I. maculatus Tshernova, Isonychia japonica (Ulmer), **I. ussurica Bajkova, Paraleptophlebia chocolata Imanishi, *Potamanthellus rarus tiunova & Levanidova, **Potamanthus formosus Eaton, P. yooni Bae & McCafferty, *P. luteus oriens Bae & McCafferty, *Phithrogena japonica Ue′no, Rhoenanthus coreanus (Yoon & Bae), *Serratella setigera (Bajkova), Siphlonurus chankae Tshernova, *S, sanukensis Takahashi 및 Uracanthella rufa (Imanishi). 별표한 種들은 幼蟲만이, 쌍별표한 種들은 成蟲만이 韓國産으로 記載되었다. (C. tshernovae와 E. keijoensis는 암컷 成蟲과 幼蟲만이, 그리고 P. luteus oriens는 亞成蟲만이 韓國産으로 記載되었다.) 다음 10종은 韓國에서 幼蟲만이 記載되었고, 아직 命名上으로 留保된 未決定種으로 남아있다. Baetis Kua: Yoon & Bae, Baetis nla: Imanishi, Brachycercus Kua: Yoon & Bae, Caenis Kua: Yoon & Bae, Cinygmula Kua: Yoon & Bae, Cinygmula na: Imanishi, Ecdyonurus Kub: Yoon & Bae, Ecdyonurus na: Imanishi, Paraleptophlebia nb: Imanishi 및 Rhithrogena na: Imanishi. 각 種에 있어서 原記載 및 再記載 文獻, 記載에 使用된 標本, 分布, 模式標本에 대한 情報, 異名과 命名上의 變動을 年代順으로 整理하였다. 附錄으로 南韓種만의 checklist와 分類學的 變動 및 國名의 變動事項을 表로 作成하였다. Mayflies (Ephemeroptera) of Korea have been described in various literatures since 1940, but there have been many taxonomic or nomenciatural changes in the members of the order. A comprehensive literature and type material review of the Ephemeroptera resulted herein the recognition of 56 nomenclaturally valid species previously described from Korea : Acerella longicaudata (Ue´no), ^*A meletus costalis (Matsumura), A. montanus Imanishi, ^*Baetis thermicus Ue´no, Bleptus fasciatus Eaton, Choroterpes altioculus Kluge, Cincticostella castanea (Allen), C. tshernovae (Bajkova), ^*Cinygmula grandifolia Tshernova, ^*C. hirasana (Imanishi), Cloeon dipterum (Linnaeus), Dyunella aculea (Allen), ^*D. cryptomeria (Imanishi), ^*D. tepnevae (Tshernova), D. triacantha (Tshernova), ^*D. trispina ezoensis (Gose), Ecdynurus bajrovae Kluge, E. dracon Kluge, ^*^*E. joernensis mongolicus Bajkova & Varychanova, E. kibunensis Imanishi, E. levis (Nava´s), E. scalaris Kluge, ^*^*E. subspinosa (Braasch & Solda´n), Epeorus curvatulus Matsumura, ^*E. hiemalis Imanishi, E. latifolium Ue´no, E. notofascia Yoon & Bae, Ephemera orientalis McLachlan, E. separigata Bae, E. strigata Eaton, Ephoron shigae (Takahashi), Heptagenia guranica Belov, H. kihada Matsurnura, ^*H. kyotoensis Gose, ^*Iron aesculus (Imanishi), ^*I. Koreanicus Braaich & Solda´n, I. Maculates Tshernova, Isonychia japonica (Ulmer), ^*^*I. Ussurica Bajkova, Paraleptophlebia chocolate Imanishi, ^*Potamanthellus rarus Tiunova & Levanidova, ^*^*Potamanthus formosus Eaton, P. yooni Bae & McCafferty, ^*^*P. luteus oriens Bae & MeCafferty, ^*Rhithrogena japonica Ue´no, Rhoenanthus coreanus (Yoon & Bae), ^*Serratella setigera (Bajkova), Siphlonurus chankae Tshernova, ^*S. sanukensis Takahashi, and Uracanthella rufa (Imanishi), The asterisked species were known to larva only from Korea, and the double asterisked were adults only (C. tshernovae and E. keijoensis were females and larvae only, and P. luteus oriens was subimagos only), The following 10 species were known to larvae only from Korea, but have not been determined: Baetis Kua: Yoon & Bae, Cinygmula Kua: Yoon & Bae, Baetis nla: Imanishi, Brachycercus Kua: Yoon & Bae, Caenis Kua: Yoon & Bae, Cinygmula Kua: Yoon & Bae, Cinygmula na: Imanishi, Ecdyonurus Kub: Yoon & Bae, Ecdyonurus na: Imanishi, Paraleptophlebia nb: Imanishi, and Rhithrogena na: Imanishi. For each species, original and secondary sources of the descriptions, materials used, type information, distributions, synonyms, aid nomenclatural changes were chronologically provided. A checklist of the Ephemeroptera previously recorded from South Korea was appended with their proposed Korean name.

당뇨병의 병형에 따른 합병증에 관한 연구(예보)

이현철,허갑범,이이형,윤정환,임승길,윤금석,김원중,김현만 대한당뇨병학회 1985 Diabetes and Metabolism Journal Vol.9 No.2

변형된 트랜스듀서 및 FM을 이용한 이식형 인공중이 시스템의 전력효율 개선

윤영호,원철호,송병섭,정영숙,김명남,박세광,이상흔,조진호 경북대학교 전자기술연구소 1997 電子技術硏究誌 Vol.18 No.2

In design of implantable middle ear system, it is necessary that the system has a high power-transfer efficiency because die internal circuit of the system has no power source. The FM transmission method transfers the signal power more efficiently than AM method because AM signal has large carrier component which act as the loss. Therefore, an implantable middle ear system using FM transmission and receiving method is proposed. And the new shape of vibrating transducer which vibrate more efficiently than the conventional type was designed. This tranducer is consisted of coil and small T-type cylindrical permanent magnet. The differences between conventional methods and proposed methods are investigated and compared through quantitive analysis. The advantages of proposed methods are proved by experiments.

LPG 탱크로리 수송중 위험성 평가에 관한 연구

이재준,김윤화,엄성인,고재욱,백종배,윤성렬 한국산업안전학회 1997 한국안전학회지 Vol.12 No.4

Demand of LPG and LNG will increase continuously due to high calories, clearness, and convenience for usage. These gases are used widely for power plants, industrial plants, and domestic fuel. But accidents related with gas are increasing in proportion to increment of gas usage. Especially, LPG has high ignitability due to weak dispersion to air and accumulation at low place because LPG is heavier than air. There are many hazards during transportation as well as production, storage, and usage of LPG. Commonly, tank lorry is used for inland transportation of LPG. If tank lorry were to raise leakage incidents and then LPG released during transporting, the accidents cause serious effects on the environment as well as human damage of surrounding area. In this study, therefore, hazards which cause LPG of tank lorry to leak during transportation were identified and risk of LPG transportation was assessed quantitatively. Also, the result of this study might be a useful measure for predicting damage and preparing safe transportation strategies of LPG tank lorry.

울진 원자력 발전소 3 , 4 호기 1 차계통 배관소재의 파괴저항특성 평가

석창성,김수용,강병구,박재실,윤병곤 한국산업안전학회 1999 한국안전학회지 Vol.14 No.1

The objective of this paper is to evaluate the fracture resistance characteristics of SA508 CL.la carbon steel, TP347 stainless steel and their associated welds manufactured for primary coolant system of Ulchin 3,4 nuclear power plants. The effect of various parameters such as pipe size, welding method, chemical composition, crack plane orientation, metallography and fractography on the material properties were discussed. Test results showed that the effect of pipe size on fracture toughness is negligible while the effect of welding method on fracture toughness is significant. In addition, the drop of fracture toughness in the field fabrication weld of TP347 stainless steel is probably due to the large amount of σ-phase precipitated on the δ-ferrite boundary and the large size dimples.

당뇨병성 경화부종 1 예

이태희,윤재영,최유창,강철민,정민영 대한내과학회 1989 대한내과학회지 Vol.37 No.1

Scleredema is a rare collagen disorder clinically characterized by marked non-pitting induration of the skin. There are two types: the classic postinfectious type and that associated with diabetes mellitus. We present a case of scleredema developed on the nape, upper portion of the back and both shoulders in a 71-year-old male who has suffered from diabetes mellitus for the past 20 years.

SUS 300 계 스테인리스강의 표면특성에 관한 연구

이경구,윤동주,기회봉,최답천,이도재 한국열처리공학회 1999 熱處理工學會誌 Vol.12 No.1

In the present study, oxidation behavior of 304 and 316 stainless steels Was investigated. After solution treatment, specimens were polished up to 1㎛ Al₂O₃grade and then subjected to oxidation treatment in dry air. The range of temperature was used for oxidation treatment at 300℃∼500℃ and TEM was used for analyzing the components and structure of oxide film. Also, these results were compared with the results of ESCA and TG. According to the results of TEM analysis, it was found that Cr oxide film was formed on top of the surface after room temperature oxidation but amorphous Fe oxide was formed on top of the surface and polycrystalline (Cr,Fe)₂O₃was formed below the amorphous Fe oxide layer after 500℃ oxidation treatment. The oxidized specimens at 500℃ showed that 316 stainless steel resists more strongly to grain and grain boundary oxidation than 304 stainless steel. These results suggested that Mo component resolved in 316 stainless steel matrix suppressed the formation of Cr carbide which may results in local Cr deplete area.

후드의 충만효과(充滿效果) 활용기법(活用技法)에 관한 연구

이상호,윤명조,김정현,강준원 한국산업위생학회 1991 한국산업보건학회지 Vol.1 No.1

In order to visualize the distribution of workplace of which mixed solvent level in air exceeded the TLV of 1.0 (ACGIH), 17 thinners used in 44 painting workplaces were analysed with gas chromatography, and their levels in air were compaired with. 1. For detection rate of solvents in thinner was highest in case of toluene(76.4%), and decreased in orders of xylene (70.6%), methylisobutyl ketone (35.3%), acetone (35.3%), methylethylketone (23.5%), isopropylacohol (17.6%), n-hexane (17.6%), styrene (11.8%), and ethylacetate (1.8%). Average number of solvents detected was 3.0. 2. Detection rates of organic solvent by component category was highest in cases of aromatic hydrocarbons (52.9%), and decreased in orders of ketones (31.4%), alcohols (5.9%), n-hexane (5.9%) and esters (3.9%). The rate by regulatory category, the second category component was detected in 93.9% of total. 3. There was significant correlation (r=0.929, p<0.01)between detection rates of solvents in thinner and in air. 4. Among the total of 44 painting workplace, the rate of them of which level of mixed solvents in air was exceeded was highest in case of aromatic hydrocarbons (29.5%), and decreased in orders of ketones (6.8%), alcohol (2.3%), n-hexane (2.3%), and was highest in guitar painting (71.4%) workplace in case of aromatic hydrocarbons by component category.