Centerless Feeder 장치의 개발

강형모,권경우,김기길,정의식,허영환 한밭대학교 산업과학기술연구소 1994 논문집 Vol.2 No.-

This paper presents results of the development of centerless feeding system which are applicable to bearing metal processes. As a result, the feeding system can be applied to automatic surface finishing on the bearing metal process such as bush, and has greatly effects on the increase of the prodnctiving and the decrease of the man power an effect on increase the productivity and decrease the man power and effect on increase the productivity and decrease the man power of the bush machining process.

漸進的·急進的 運動負荷가 血液의 pH, Sugar 및 Lactate에 미치는 影響

姜炯基,辛元太,白永守,殷熙寬,宋基成,河哲秀 漢陽大學校 體育科學硏究所 1986 體育科學 Vol.6 No.6

The purpose of this study is to in-vestigate the effects of gradual and radical exercise load on the treadmill for PH, Sugar and Lactate in Blood by selecting 14 subjects in H university, All subjects began exercise by 6mPH for 4 minutes at start and increased exercise speed up to HR 140 by increasing every minute as gradual load. And subjects began exercise by 9mPH at first and increased load up to HR 140 as radical exercise load. The results are as follows: (1) In PH in Blood, gradual exercise load is lower than radical training in all subjects. (p<0.05) (2) In Sugar in Blood, radical exercise load is higher than gradual exercise load in all subjects. (p<0.05) (3) In Lactic Acid in Blood, gradual training is higher than radical exercise load in all subjects. (p<0.01) (4) In Lactic Acid, all subjects showed high value and its is also in Sugar, than the method of exercise load is according to anaerobic energy metabolism.

제주시 지역 강수의 특성 분석 : 1997-1998년 빗물의 산성화 특성

강창희,김원형,홍상범,이기호 제주대학교 환경연구소 1998 환경연구논문집 : 제주대 Vol.6 No.-

The precipitation samples were collected in Cheju city and the major soluble ions were analyzed during the period of October in 1996 to August in 1998. The volume-weighted mean value of pH was 4.82. and that of electric conductivity was 23.3㎲/cm. The mean concentrations of ions in Cheju city have been found in the order of Cl^(-) > Na^(+)> SO_(4)^(2-)> NH_(4)^(+)> NO_(3)^(-) > H^(+) >Mg^(2+)>Ca^(2+)>K^(+)> HOOO^(-)> F^(-) >CHO_(3)^(-) >CH_(3)S0_(3)^(-). The comparison between several correlation coefficients has been applied for the investigation of analytical reliabilities. such as equivalent concentrations sum. the measured and calculated conductivity, and the acid fraction. It showed a value of over 0.936 so that the analfid data has been in good rehability. Also. the ionic strengths of the precipitation were obtained as well as the effect of the sea-salt components. The origins of the precipitation components in Cheju city were studied with a factor analyzing way, and they showed the most probable factor as anthropogenic. oceanic, soil-sourced, respectively. The concentration of CHEOOH was hlgher than that of HCOOH, and there was also a small contribution in acidty by organic acids. From the MSA analyses, it was found that the air in Cheju city has been influenced by the pollution from the other areas. The neutralization factors were 0.36-0.56 for NH_(4)^(+), 0.12- 0.25 for Ca^(2+). and the free acidity was 19-60%. The results of multiple regression analysis has shown that the acidification contribution of acidc gas (H_(2)SO_(4), HNO_(3)) was about 24%.

흰쥐 경동맥 손상 모형에서 체외 방사선조사에 의한 신내막 과증식억제 : Intercellular Adhesion Molecule-1과 Vascular cell Adhesion Molecule-1의 역할 The Possible Role of Intercellular Adhesion Molecule-1 and Vascular Cell Adhesion Molecule-1

강동헌,승기배,장기육,임상현,정해억,임효영,김연실,채장성,김재형,홍순조,최규보 대한순환기학회 1999 Korean Circulation Journal Vol.29 No.9

교환기를 위한 장애진단용 지식 기반 시스템

강지훈,홍기형,이성인 충남대학교 기초과학연구소 1994 忠南科學硏究誌 Vol.21 No.1

We study knowledge-based systems for diagnosing faults in switching systems. We survey many knowledge-based systems for telecommunications. Especially, we analyz the ACE expert system developed by the Bell Laboratory of AT&T, which is the first expert system in the telecommunication area. Its motivation, development and configuration are examined thoroughly. From this survey, we propose an architecture for a knowledge-based system based on deductive database technologies for telecommunication areas.

기계적 합금화에 의한 Cr-Si계 혼합분말의 상형성 거동

강기혁,이진형 국민대학교 생산기술연구소 2002 공학기술논문집 Vol.25 No.-

The sequence of phase formation during MA (mechanical alloying) of Cr-Si powder mixtures was studied using SPEX 8000 mixer/mill. The chemical compositions of the powder mixtures were Cr-25at%Si, Cr-37.5at%Si, Cr-50at%Si, and Cr-66.7at%Si respectively. A powder mixture of elemental Cr and Si was premilled in an argon-filled jar type ball mill during 24 hours and then mechanically alloyed by SPEX 8000 mixer/mill. MA was carried out from 1 hr to 24 hrs, and the phase formation behavior was investigated by XRD, SEM, and DTA. In the case of Cr-37.5at%Si, Cr-50at%Si and Cr-66.7at%Si, CrSi₂ was always the first phase to form and then CrSi₂ could react with Cr to form Cr_(5)Si₃. This is similar to the sequence of phase formation during annealing of multilayer chromium and silicon thin film. In the case of Cr-25at%Si, Cr₃Si was the first and only phase to form during MA. This was interpreted that metastable supersaturated Cr solid solution was formed prior to the formation of Cr₃Si and then Cr₃Si formed from a solid state precipitation reaction of this solid solution. However, the similar sequences of phase formation during annealing of multilayer chromium and silicon thin film were achieved by heat treating the MAed powders. Therefore, the mechanism of the mechanically alloyed Cr-Si powder system was the thin film reaction based on diffusion rather than SHS (self-propagating high temperature synthesis).

청정 지역 강우의 분석 : 1997-1998년 한라산 1100 고지와 제주시 강우의 특성 Characteristics of Rainwater at 1100 Site of Mt. Halla and Cheju City in 1997-1998

강창희,김원형,홍상범,이기호,홍민선,심상규 濟州大學校 基礎科學硏究所 2000 基礎科學硏究 Vol.13 No.1

The rainwater samples were collected from the 1100 Site of hlt. Halla and Cheju city during the period of March in 1997 to August in 1998. and the major soluble ions were analyzed. The confidence of analytical data was confirmed by using the comparison methods such as ion-balance, electric conductivity and acid fraction. all of which correlation coefficients were above 0.94. The ionic strengths lower than 10^(-4)M, the basis for the pure rainwater, were found in 47% and 38% at 1100 Site and Cheju city, respectively. The precipitations in Cheju city were more influenced by the oceanic effect than those in 1100 Site. The acidity contribution was mainly by SO_(4)^(2-) and NO_(3)^(-) in both areas. and the organic acids have contributed to the acidity with only 5-7%. The neutralization factors by NH_(3) were about 46% at both 1100 site and Cheju city, whereas those by CaCO_(3) were 11% and 15% at 1100 site and Cheju city respectively, and the free acidity were both about 35% in average. From the MSA analysis. it was found that the air in Cheju island has been influenced by the pollution from the other areas. The sources of the rainwater components in 1100 Site and Cheju city were also studied with a factor analyzing way and the most probable factors were found to be anthropogenic, oceanic, and soil-sourced. The results of multiple regression analysis have shown that SO_(4)^(??) was dissolved mostly in the form of H_(2)SO_(4), CaSO_(4) and (NH_(4))_(2)SO_(4). and NO_(3)^(-) was in the form of HNO_(3), Ca(NO_(3))_(2) and NH_(4)NO_(3).

수동유적 움무덤 출토 유리구슬의 화학조성

강형태,정광용,이기길 호남고고학회 2003 湖南考古學報 Vol.18 No.-

전남 영광군 화평리 수동마을 움무덤에서 출토된 유리 시료 18점의 화학조성을 분석하기 위하여 주사전자현미경에 부착된 파장분산형 X-선 분석기를 사용하였다. 유리구슬의 색깔은 크게 녹청색, 감청색, 감색 및 투명한 것으로 나뉘었다. 각 시료에 대하여 10종의 산화물을 분석한 결과 투명유리를 제외하고는 모두 칼리계 유리로서 K2O 함략이 17.2~19.6% 범위였다. 투명유리는 다른 유리구슬에 비해 실리카 함량이 93~94%로서 높고 K2O 함량이 2~4%인 비결정성 물질임을 X-선 회절분석으로 확인하였다. 녹청색 유리는 구리가 착색원소로 착용한 것이며 감청색 및 감색은 미량의 코발트 성분이 착색원소로 작용한 것으로 추정되었다. 감청색과 감색의 차이를 성분 함량으로 살펴본 결과 감청색은 망간의 농도가 1% 이하이고 감색은 1.4~1.8%의 농도를 나타내었다. 이 분석결과는 전남 영광지역의 철기시대 유리제작기술을 알려주며 이러한 분석 사례가 쌓이면 시대별, 지역별 유리의 특성을 밝히는 연구도 가능할 것이다.

누두흉 환자에서 Nuss 금속막대 제거 전 · 후 폐 역학 변화

강규식,백남순,김천숙,안기량,권진형,김지은,유시현 순천향의학연구소 2003 Journal of Soonchunhyang Medical Science Vol.9 No.1

Nuss operation is one of the surgical procedure for pectus excavatum and it's method is the insertion of convex steel bar under the sternum through small bilateral thoracic incision. As the patients is growing, the thorax can be compressed gradually by steel bar. So Nuss bar needs to be removed two years after Nuss operation. This study was undertaken to assess the effect on the repiratory mechanics before and after the removal of the Nuss bar. Twenty patients with previous Nuss operation were allocated for the removal of Nuss bar. Lung mechanics (dynamic lung compliance, static lung compliance, and airway resistance), hemodynamic change (heart rate, systolic pressure, and diastolic pressure), and pulmonary gas exchange (arterial oxygen tension, arterial carbon dioxide tension, pulse oximeter saturation, and end tidal carbon dioxide tension) were measured before and after removal of Nuss bar. Respiratory mechanics (dynamic and static lung compliance, inspiratory airway resistance), pulmonary gas exchange and hemodynamic parameter were unchanged before and after the removal of Nuss bar. We concluded that lung mechanics were not changed before and after the removal of Nuss bar in the patients with pectus excavatum and the 95% patients were satisfied with operation.

악성 갑상선 우연종의 임상상 및 초음파 소견의 진단적 가치

강한욱,김광원,이병완,강보현,김형훈,김범진,정재훈,민용기,이명식,이문규 대한내분비학회 2002 Endocrinology and metabolism Vol.17 No.5

연구배경: 최근 갑상선 초음파 검사의 빈번한 시행으로 갑상선 우연종의 발견이 증가하고 있다. 이러한 갑상선 우연종은 임상적으로 어떻게 접근하고 치료를 해야 하는지 적지 않은 문제가 되고 있다. 본 연구에서는 직경 1.5㎝ 이하의 갑상선 우연종의 유병률, 입상적 특징 및 초음파 특성, 그리고 가장 효율적인 진단적 접근에 대해 알아 봤다. 방법: 1999년 1월부터 2000년 12월까지 삼성서울병원 내과 및 일반외과로 갑상선 결절을 주소로 내원한 1457명을 대상으로 후향적 연구를 시행하였다. 우연히 발견된 직경 1.5㎝ 이하의 갑상선 결절을 가지는 환자들에서 갑상선 결절의 촉지 유무, 갑상선 기능검사, 항갑상선 항체, 갑상선 초음파 및 미세침 흡인세포검사, 99m^Tc 갑상선 스켄, 수술 조직검사 및 병기를 검토하였다. 결과: 분석한 갑상선 결절 1475예 중 갑상선 우연종의 유병률은 13.4%(198예)였다. 갑상선 우연종에서 악성률은 28.8%(57예)으로 나왔다. 양성 및 악성 갑상선 우연종에서 나이, 성별, 갑상선 기능검사, 결절 크기에는 의미 있는 차이는 없었다. 갑상선 스켄은 갑상선 우연종의 감별에 적합하지 않았다. 갑상선 결절의 초음파 지표 점수만이 양성 및 악석 갑상선 우연종의 감별에서 초음파 지표 점수의 민감도는 88.9%, 특이도는 74.4%, 양성 예측률은 92.4%로 나왔고 진단적 정환도는 85.5%였다. 갑상선암으로 수술을 받은 50명중 stage 1은 34명, stage 2는 6명, stage 3은 10명으로 대부분의 악성 갑상선 우연종은 낮은 TNM 병기로 나타났으나, 상당수에서는 국소 침범의 소견을 보였다. TNM 병기의 3기 환자 전부는 45세 이상이였고, 주로 갑상선암의 피막 침범에 의한 것이었다. 임파절 전이는 6명의 환자에서 나왔다. 결론: 악성 갑상선 우연종은 비교적 흔히 접할 수 있는 질환이며 양성 우연종과는 임상적으로 구별이 안 된다. 악성 갑상선 우연종은 발견 당시 대부분 낮은 병기이나, 갑상선의 피막 침범 및 임파절 전이가 상당수에서 발견되었다. 갑상선 우연종의 초음파 소견은 향후의 진단 방향을 제시하는 중요한 길잡이가 될 수 있다. 초음파 지표 점수 2점 이상의 갑상선 우연종에서만 초음파 유도 미세침 흡입검사를 권장한다. Background: High-resolution ultrasonography has made the detection of asymptomatic small thyroid possible. Recent increases in the detection of incidentalomas have created a clinical dilemma on how to properly manage such incidental nodules. We investigated the prevalence, clinical and ultrasonographic characteristics, and optimal diagnostic approach toward incidentally detected benign and malignant thyroid nodules of less than 1.5㎝ in size. Methods: A retrospective review was undertaken on the 1,475 patients who had visited Samsung Medical Center, Seoul Korea between January 1999 and December 2000. The review consisted of a physical examination of the thyroid gland, thyroid function test, antithyroid antibodies, thyroid ultrasonography, fine-needle aspiration biopsy, pathology and TNA staging of the incidentally detected thyroid nodules of less than 1.5㎝ in size. Results: The prevalence of thyroid incidentalomas was 13.4% and the malignancy rate within them was 28.8%. There were no significant differences in age, sex, thyroid function test and size between the benign and malignant incidentalomas. Ultrasonographic characteristics showed meaningful diagnostic value for the detection of malignancy in incidentalomas. Most malignant incidentalomas were of a low stage. Conclusion: Occult thyroid cancers are fairly common finding. There are no clinical difference between benign and malignant thyroid nodules less than 1.5㎝; however, ultrasonographic findings can be used to decision of optimal management strategies (J Kor Soc Endocrinol 17:649∼656, 2002).