치과환자에서 경동맥 석회화 유발율에 대한 전산화단층사진 연구

윤숙자,이재서,윤웅 대한구강악안면방사선학회 2006 Imaging Science in Dentistry Vol.36 No.3

Purpose : Stroke is one of the leading causes of death in Korea. Atherosclerotic disease in the carotid artery bifurcation is the most common cause of stroke. The carotid artery calcification is easily appreciated by CT (Computed tomography). CT is often taken in a dental hospital for the diagnosis of inflammation, injury, cyst or tumor on maxillofacial region. However, there was no report of carotid artery calcification on CT in dental patients. This study was to determine the prevalence of carotid artery calcification on CT in dental patients. Materials and Methods : The presence of carotid artery calcification was evaluated by an experienced radiologist on CT scans of 287 patients (166 males, 121 females, average age 42, range 6 to 86 years) and the medical history of the patient and the interpretation of CT were reviewed. Results : Carotid artery calcification was detected on CT scans of 57 patients (19.8%; 35 males, 22 females). All the male patients with carotid artery calcification were older than 50, and all the female patients with carotid artery calcification were older than 60. Among the 57 patients, 10 had Diabetes mellitus, 20 had cardiovascular disease, 3 had history of stroke and 3 underwent radiation therapy for head and neck cancer. Carotid artery calcification was not included in the interpretation of CT of dental patients except one patient. Conclusion : The prevalence of carotid artery calcification on CT of dental patients was about 20% in this study. Carotid artery calcification should be included in the interpretation of CT of dental patients.

CAD/CAM 시스템 導入效果에 관한 考察

尹在坤,金明淑 효성여자대학교 산업경영연구소 1988 경영경제 Vol.5 No.-

CAD/CAM will play an ever increasing role in design and production circles. It is likely to be one of the major growth areas of the 80's and 90's. Because, manufacturing management today is challenged by competitive pressures from abroad, cost pressures from within and shorter product life cycles from changing markets. CAD/CAM system is to design a product, assembly or part on the computer and run the appropriate software programs to obtain all of the desired manufacturing outputs. A CAD/CAM function is shown as follow: <본문참조> For the effective application of CAD/CAM system in Korea, the application effects of the system were measured in S Company. The results of measurement showed that 37.5% of machine running was advanced and 629% of cost reduction was obtained. In addition, it R&D time. In conclusion CAD/CAM system is considered to be greatly effective on manufacturing areas.

상악 매복 견치와 관련된 석회화 치성낭

윤숙자,김영희,이재서 대한구강악안면방사선학회 2000 Imaging Science in Dentistry Vol.30 No.3

A 35-year-old man was referred to the department of Oral and maxillofacial surgery of Chonnam university hospital for the chief complaint of asymptomatic swelling on the buccal vestibule of upper right canine area. Radiographs revealed that the upper right canine was impacted and there was a well-circumscribed pericoronal radiolucency related with the canine. Multiple radiopaque foci were scattered in the radiolucent lesion, and the roots of the lateral incisor and the first premolar related to the lesion showed external resorption. The radiographic features of this lesion were typical of adenomatoid odontogenic tumor, but considering the gender and age of the patient, the tentative diagnosis was made as calcifying odontogenic cyst. Microscopically this lesion was diagnosed as calcifying odontogenic cyst, Because calcifying odontogenic cyst has no pathognomonic feature of radiographs, to consider radiographic features with clinical findings is necessary in order to establish more correct diagnosis.(Korean J Oral Maxillofac Radiol 2000; 30: 223-227)

토양환경지도 자료를 이용한 콩밭 토양의 화학성 비교

박지숙,이민진,정재원,김미혜,이서연,지윤미,한준호,김유학,공명석,한광현,노희명 忠北大學校 農業科學硏究所 2015 農業科學硏究 Vol.31 No.2

It is important to interpret the soil chemical properties in order to effectively manage the farmland. This study was conducted to investigate the soil chemical properties of upland soybean field according to the soil series at 32 upland fields located in the parts of Gangwon-do. Soil sampling sites were selected by using the National Statistics DB and KSIS DB that is a soil environment information system provided by the Rural Development Administration. Soil samples were collected from 0~15 cm of top soil before seeding or transplanting, air-dried, passed through a 2 mm sieve, and analyzed for soil pH, EC, organic matter, available phosphorus (P2O5), exchangeable potassium, exchangeable calcium and exchangeable magnesium. The average chemical properties have exceeded the each nutrient optimum range level of RDA, except the organic matter in experimental soil 2015. And despite application of conventional fertilization, each soil series nutrient contents were change respectively. The results of this study suggest that conventional fertilization should be applied based on the analysis about the amount of accumulated nutrient contents in the soil.

대장암에서 Glucose Transporter Gene의 발현

이석환,박재훈,김윤화,오수명,윤충,주흥재,이기형 대한대장항문학회 2000 Annals of Coloproctolgy Vol.16 No.2

수완진동 증후군에서 신경장해의 조기진단을 위한 객관화된 방법

윤재국,이헌,최나리,김석환,박형욱,이지호,유철인 大韓産業醫學會 2009 대한직업환경의학회지 Vol.21 No.2

목적: 통각과 진동감각 역치검사 및 수부와 수지의 악력, 그리고 수지의 운동기능검사(태평) 등과 근로자들이 호소했던 증상에 대한 HAVS의 스톡홀름 워크샵 분류와의 관련성을 통해 좀 더 객관화된 신경학적 조기검사 방법을 찾고 타당성을 검증하고자 하였다. 방법: 2000년 1월부터 2007년 12월까지 수부진동에 폭로되고 수부의 불편함을 호소하여 진동 장해에 대한 검사를 시행한 497명의 근로자를 대상으로 하였다. 일차적으로 문진을 통해 직업력에 대해 알아보고 과거력을 조사했다. 대상자들의 스톡홀름 워크샵 분류에 따른 소견을 확인하고 수부의 말초 순환기능 검사(손톱압박, 수지피부 온도), 신경기능 검사(통각과 진동각 역치), 운동기능 검사(악력, 태평) 등을 시행하였다. 다른 질환의 감별을 위한 몇 가지 이학적 검사를 실시하고 스톡홀름 워크샵 분류에 따른 검사 결과들을 분석하였다. 결과: 사용 도구는 그라인더 단독 사용이 265명 (67.3%)으로 가장 많았으며 평균 노출 연수는 14.8년이었다. 통각과 진동감각에서 스톡홀름 워크샵 분류 단계에 따른 역치가 증가하는 경향을 보였으나 통각은 양측 모두 통계적인 유의성이 없었고, 진동감각은 125와 250 Hz에서 양측 모두 유의했다(p=0.006-0.038). 수부와 수지의 악력은 단계가 올라갈수록 감소하는 경향을 보였지만 수부와 수지 모두 우측에서만 통계적으로 유의했다 (p=0.041, p<0.01, p=0.034). 태평 첫수는 단계가 올라 가면서 전반적으로 태핑 첫수가 감소하였으며 좌측에서만 통계적으로 유의했다(p=0.002-0.019). 결론: 본 연구는 수부 진동 노출자들의 수부 불편함에 대한 신경계통을 초기에 정량적으로 객관화하여 진단할 수 있는 단일 방법은 아직 없으며 일상생활의 불편함과 스톡홀름 워크샵 분류 등을 통한 주관적인 증상에 더하여 수지 통각과 진동감각 역치검사, 수부와 수지 악력검사, 운동기능검사(태핑) 등을 통합하면 초기에 객관적으로 진단하는 것이 가능할 것으로 판단된다. Objectives: In order to determine find out the best methods for a more objective detection of neurologic abnormality in early hand ann vibration syndrome(HAVS), early with analyzing the validity of each of the detection methods was analyzed. We evaluated the relationships between the sensorineural stage of Stockholm-revised vibration syndrome classification and the results of several tests. Methods: 497 workers were investigated for symptom, exposure duration, the types of tools used, and medical history from January 2000 to December 2007. Pain sense threshold, vibrotactile threshold, hand grasp force, finger grasp force, and a finger tapping frequency test were performed by the workers. Results: The grinder(67.3%) was the most commonly used tool and the mean exposure duration was 14.8 years. Although the pain sense and vibrotactile threshold level tended to increase according to sensorineural stage of the Stockholm classification, there was statistically significant difference in the vibrotactile threshold of 125, 250 Hz (P=0.006~0.038) but not in the pain sense threshold. Hand and finger grasp force tended to decrease according to the sensorineural stage of Stockholm classification and there was statistically significant difference(P=0.041, <0.001, 0.034) only on the right hand side. The tapping frequency also generally decreased according to the sensorineural stage of the Stockholm classification and there was statistically significant difference (P=0.002~0.019) only on the left hand side. Conclusions: Although there is no single standardized method that can objectively diagnose the Sensorineural component of early HAVS early, the combination of subjective symptoms, the sensorineural stage of Stockholm classification, the pain and vibrotactile threshold test, the hand and finger grasp force, and the finger agility (tapping) test can objectively detect sensorineural component of HAVS early.

직접 산화법에 의한 알루미늄/산화알루미늄 경사기능재료의 제조

金錫胤,金載潤 弘益大學校 科學技術硏究所 1995 科學技術硏究論文集 Vol.6 No.-

Funtionally gradient Material is designed to have ceramic rich phase on its surface and metal rich phase at the inner part of the sample. The contents of the ceramic phase must decrease gradually as the distance from the surface increase. In this study, the directed matal oxidation process was used to synthesize the Ceramic/Al Functionally Gradient Materials. Aluminum powder pellets containing Mg and Al2O3 powder were heated to the reaction temperature(900℃) under air atmosphere. This process can simplify the processing steps of the conventional fabrication process of the functionally gradient materials. Microstructures of the reaction products were investigated using Optical Microscopy, XRD and SEM. Microstructures of the reaction products indicated that the reaction products have a dense layer on their surface. The reaction layer was consisted of a ceramic rich layer at outer surface, followed by a channelled structure layer in which metallic aluminum content is approximately 50vol%. The thickness of the product layer varied from 50 to 300㎛ and its hardness decreased smoothly from the surface. The effects of the processing variables which include alloying elements, diluents, reaction temperature on the thickness and microstructure of the reaction product was investigated.

적외선 열화상 카메라를 이용한 머시닝 센터 주축 열변위에 관한 열해석

김재열,윤성운,임노빈,유신,마상동,양동조,송인석 한국공작기계학회 2001 한국공작기계학회 춘계학술대회논문집 Vol.2001 No.-

Diagnosis or measurements using Infrared thermo-image hasn't been available. A quick diagnosis and thermal analysis can be possible when that kind of system is introduced to the investigation of each part. In this study, Infrared Camera, Thermo-vision 900 was used in order to investigate. Infrared Camera usually detects only Infrared wave from the light in order to illustrate the temperature distribution. Infrared diagnosis system can be applied to various field. Also, it is more effective to analyze temperature distribution on the machining center main-axis process.

치과 방사선 촬영기의 표면선량 변화

이재서,강병철,윤숙자 대한구강악안면방사선학회 2005 Imaging Science in Dentistry Vol.35 No.2

Purpose : The purpose of this study was to investigate variability of doses with same exposure parameters and evaluate radiographic density according to the variability of doses. Materials and methods : Twenty-eight MAX-GLS (Shinhung Co, Seoul, Korea), twenty-one D-60-S (DongSeo Med, Seoul, Korea), and eleven REX-601 (Yoshida Dental MFG, Tokyo, Japan) dental x-ray machines were selected for this study. Surface doses were measured under selected combinations of tube voltage, tube current, exposure time, and constant distance 42 cm from the focal spot to the surface of the Multi-O-meter (Unfors Instruments, Billdal, Sweden). Radiographic densities were measured on the films at maximum, minimum and mean surface doses of each brand of x-ray units. Results : With MAX-GLS, the maximum surface doses were thirteen to fourteen times as much as the minimum surface doses. With D-60-S, the maximum surface doses were three to eight times as much as the minimum surface doses. With REX-601, the maximum surface doses were six to ten times as much as the minimum surface doses. The differences in radiographic densities among maximum, mean, and minimum doses were significant (p<0.01). Conclusion : The surface exposure doses of each x-ray machine at the same exposure parameters were different within the same manufacturer’s machines.

Al₂O₃纖維 强化 알루미늄 複合材料에서 合金元素 添加가 界面反應에 미치는 影響

金錫胤,宋在京,金政根 弘益大學校 1986 弘大論叢 Vol.18 No.2

In the fabrication of the fiber reinforced aluminum alloy composites was made by liquid metal vacuum infiltration. Emphasis was placed on the study addition of alloying elements to matrices and interface interactions between fiber and matrices. Al₂O₃fiber well wetted in Al-Mg, Al-Li and poorly in Al-Cu-Mg alloys but pure Al and Al-Cu matrices bad wetted. The distribution of constituents at the interaction zones between reinforcements and matrices was analysed by EDS and WDS.