상대농도와 질량농도 측정법에 의한 기중 분진농도의 비교

정광호,성수원,안규동 가톨릭대학산업의학센타 산업의학연구소 1983 韓國의 産業醫學 Vol.22 No.1

This experiment was carried out to investigate the correlation of accuracy among five kinds of instruments which determined an airborne dust at the various locations of same type work. The results obtained were as follows; 1. Digital dust indicator-P type (DDI-P) instrument for determination of relative concentration was found not having significant variations when it was used without corrective coefficient to the quantitative concentration at the places with a few airborne dust in office and laboratory room. 2. Generally, there were the high correlations between determination values resulted by Digital dust indicator(DDI) and Piezobalance(PB). However, the correlation of two instruments to a filter weighing method was insignificant in the same type work. After determining several times (at least 5 times and over), it was desirable to fix the corrective-coefficient. 3. When the size of the particles of airborne dust was large or its concentration was high in suspended airborne dust, the determination values of High volume air sampler-Respirable(HVS(R)) were 2-4 times higher than that of Low volume air sampler-Respirable(LVS(R)). 4. The emyloyment of corrective coefficient for determination values of DDI and PB was not appropriate to HVS(R) comparing with LVS(R) because of the significant changeable differences. In addition, the determination instruments for relative concentration was not appropriate to using by itself at a manufactruing process. There were also problems about sampling time and evaluation when it was determined the total airborne dust with the open face type holder.

미국 개미취 根 Aster divaricatus L.의 성분 연구(一)

鄭東奎 淑明女子大學校 1977 論文集 Vol.17 No.-

Aster divaricatus LINNE'(Compositae) is a perennial plant which is distributing in the all of area of the United States of America. This plant has been reported that it is using for anti-tumor agent on Ameria. Recently, Dr. Norman R. Farnsworth, Professor of Pharmacognosy at the college of Pharmacy, University of Illinois predicted that Astersaponin obtained from the root of Aster divaricatus will be tri-terpene saponin and it will be available for anti-tumor. However, the active constitvents didn't isolate yet from the plant. I got eight fractions from the petroleum ether extract and marc of the root of the plant. (Chart I). Five compounds were isolated from fraction A among the eight fractions by using column chromatography method. (Tab. Ⅳ) According to the view of IR spectra, mp. etc. (Fig. 3 Fig. 4, Fig. 5, Fig. 6, Fig 7) 5 compounds are presumed as alkanes CH_3(CH_2)_nCH_3.

EKF를 이용한 유도전동기의 속도센서리스 백터제어

鄭東和,朴奎南 순천대학교 공업기술연구소 1994 工業技術硏究所論文集 Vol.8 No.-

In field oriented control of induction motors, speed sensor is required which reduces the sturdiness of drive system and together with the expenditure of hardware for faultless transmission and processing of sensor signals it causes considerable expenses. These expensive sensor can be replaced by speed sensorless concept. And for good control, the knowledge of the rotor flux component or the rotor resistance are needs. This paper is based on a extended kalman filter(EKF) that estimates the state variables that are required for the control by only measuring the line voltage and current of the machine The rotor resistance and speed estimated by the EKF shows satisfactory agreement with actual values with simulation.

Insulated Gate Transistor의 설계 및 제작

정상구,김진형,최연익,이동엽,황성규,성만영 亞洲大學校 1988 論文集 Vol.11 No.-

In this paper, we discuss fabrication and characteristics of the singular and the array-type insulated gate transisters(IGT). The starting wafers were two kinds: for a singular type IGT, p type(100) silicon with n??buffer and n??epitaxial layer; for a array-type IGT, p type(111) silicon with the n??epi layer. The channel regions were defined using the self-aligned double-diffusion process. Aluminum and poly silicon gate were used in the singular and array-type IGT, respectively. Characteristics of the singular IGT shows threshold voltage of 4 V, breakdown voltage of 73V and forward voltage drop of 0.7V. On the whole, the experimental results were in agreement with the theoretical ones when comparing the breakdown voltage and forward voltage drop. On the other hand, array-type IGT shows poor I-V characteristics, relatively low breakdown voltage and large leakage current.

騷音性 難聽에 對한 聽覺學的 考察

丁東奎 대한이비인후과학회 1976 대한이비인후과학회지 두경부외과학 Vol.19 No.3

騷音性難聽에 對한 聽覺學的 考察

丁東奎 충남대학교 대학원 1976 論文集 Vol.6 No.-

Audiological evaluation was performed for 184 female weavers(351 ears), who were 18~25 years old and have been working under the exposure of 103~105 dBa of machinery noise With the duration of employment they were divided into five groups under 1 year, 1~2 years, 2~3 years, 3~4 years and over 4 years The following results were obtained, 1) Theindcience of noise induced hearing losswas 39.7%(36.2% of ears) and rapidly increased during first 1~2 years 2) The average maximum hearing loss on the pure tone audiograms appeared at 4,000 ㎐ with about 40 ㏈ of hearing level The average hearing level at high frequencies (3,000 ㎐-8,000 ㎐) showed below 25 ㏈ of hearing level in all groups and had the tendency to increase slightly with the duration of working, but themost of hearing losses developed during first one year except at 8,000 ㎐ 3) The average hearing levelat speech frequencies was within normal range but the cases of hearing level over 25 ㏈ at 2,000 ㎐ was 27.% 4) The cases with maximum hearing loss at 4,000 ㎐ were 72.7% but the cases of maximumhearing loss at the other frequencies (3,000 ㎐, 6,000 ㎐ and 8,000 ㎐) were also observed and they increased slightly in numbers with the duration of working The noise induced hearing loss under the exposure of 103~105 dBA for 5 years, seemed to develope during first 1~2yars and there after slightly increase hearing loss was showed but no edarkable changes weer observed rem.

드라이브 일렉트로닉스의 동향과 전망

鄭東和,朴奎南 순천대학교 공업기술연구소 1993 工業技術硏究所論文集 Vol.7 No.-

Drive electronics has been defined as multi-disciplinary technology that encompasses power semiconductor devices, converter circuits, electrical machines, signal electronics, control theory, microcomputers, VLSI circuits and CAD techniques. Although drive electronics engineers polarized in a narrow segment of the spectrum in this area should have more or less experience in all the above component disciplines. This is indeed a challenge since most these disciplines are going through fast technological evolution. This paper describes technology trend and view with AC drive of drive electronics.

고등학교 지구과학 실험·실습 요목 비교 분석

정원우,이윤종,기우항,김영호,양승영,강용희,안병호,임성규,윤일희,김중욱,윤성효,강동진 경북대학교 과학교육연구소 1997 科學敎育硏究誌 Vol.21 No.-

The purpose of this study is to investigate the status of the experimental and practical education in high school earth. The present status and reasonable management of the experimental and practical education in high school earth science have been grasped from the questionaires. To do this, eighty eight earth science teachers in Korea are administered questionaires. The frequency of the experimental and practical items in the seven kind of earth science text books were investigated. The problems and the reasonable management for experimental and practical education were proposed in this paper.

세균독소로 자극시킨 사람 섬유아 세포에서의 Interleukin-6와 Interleukin-8의 생성

정인교,양동규,홍시영,이성근,김욱규,김광혁,김종렬 大韓顎顔面成形再建外科學會 1999 Maxillofacial Plastic Reconstructive Surgery Vol.21 No.4

Cytokines are hormone-like proteins which mediate and regulate inflammatory and immune responses. Interleukin-6 (IL-6) is involved in the final differentiation of B cells into antibody-producing cells. Interleukin-8 (IL-8) is a neutrophil chemotactic factor that plays an important role in the recruitment of neutrophil to inflammatory loci. Inflammatory mediators by cells in the gingiva have been implicated in the initiation and progression of periodontitis and oral infection. The purpose of this study was conducted to investigate the effect of lipopolysaccharide (LPS), staphylococcus enterotoxin B (SEB) on production ofIL-6 and IL-8 by human gingival and facial dermal fibroblasts. Primary cultured human gingival and facial dermal fibroblasts were incubated with LPS(0.01, 0.1, 1.0㎍/ml), SEB (0.01, 0.1, 1.0㎍/ml) or LPS (0.1㎍/ml) plus SEB (0.1㎍/ml). Culture supernatants were collected at 24, 48, and 72 hrs and assessed for IL-6 and IL-8 production by enzyme-linked immunosorbent assay. IL-6 production in gingival fibroblasts stimulated with LPS was higher than that with SEB. IL-6 production by double exposure with LPS plus SEB was amplified in comparison with single exposure of LPS or SEB. IL-6 production in facial demal fibroblasts was increased only by stimulation with a high concertration of LPS (1.0㎍/ml). Its production in facial dermal fibroblasts by exposure with SEB was decreased in comparison with control, nontreated cells. Therefore, gingival fibroblasts showed higher sensitivity than facial dermal fibroblasts in response to low concentration of LPS. Also, IL-6 production by double exposure with LPS plus SEB was amplified in comparison with single exposure of LPS or SEB.IL-6 production in facial dermal fibroblasts was increased only by stimulation with a high concentration of LPS(1.0㎍/ml). Its production in facial dermal fibroblasts by exposure with SEB was decreased in comparison with control, nontreated cells. Therefore, gingival fibroblasts showed higher sensitvity than facial dermal fibroblasts in response to low concentration of LPS. Also, IL-6 production by double exposure with LPS plus SEB was amplified in comparison with single exposure of LPS or SEB. IL-8 production in gingival fibroblasts was enhanced greatly only by stimulation of high concentration of LPS (1.0㎍/ml). That by exposure with SEB was increased only in 24 hrs cultivation. IL-8 production by double exposure with LPS plus SEB was amplified in comparison with single exposure of LPS or SEB. IL-8 production in facial dermal fibroblasts was decreased by LPS and increased only in 48 hrs cultivation by SEB. IL-8 production by double exposure with LPS plus SEB was enhanced only in 48 hrs cultivation in comparison with single exposure of LPS or SEB. therefore, IL-6 and IL-8 production were released at various quantities according to bacterial toxin applied and site of fibroblast harvested. These results suggest that gingival fibroblasts may be concerned with IL-6 and IL-8 related inflammatory response more than facial dermal fibroblasts.

병원 업무 전산화를 위한 컴퓨터 네트워크 구성에 대한 연구

정동근,김규호,김명관 서울보건대학 1995 서울보건대학 부설 병원경영연구소 논문집 Vol.1 No.1

This paper presents the medical networking Environment and the architecture of Integrated Medical Information System(IMIS). Thease results are drived from environmental transformation of Medical Market in Korea. Especially we study various case work for competition hospitals. We interest some new concepts for logistics re-engineering, Virtual Corporation, Electronic Data Interchange, chart automation, Decision making Support System. Thease concepts include to our study for IMIS and medical networking environment.