원위 대퇴골의 고립성 골연골종에서 발생한 속발성 연골 육종 1례 보고

정필현,황장수,강석,김용민,오형호,채동주,김종필 동국대학교 경주대학 1996 東國論集 Vol.15 No.-

연골육종은 비교적 서서히 자라며 늦게 전이하는 악성 연골 종양으로 알려져 있다. 골 연골종에서 발생한 속발성 연골육종은 발생빈도는 드물며 타부위로의 전이가 적고 악성도가 낮은 경우가 많아 적합한 수술적 치료로서 좋은 예후를 보이는 것으로 보고되고 있다. 본 동국대학교 정형외과학 교실에서는 우측 대퇴골 원위부 골간단부에 생긴 고립성 골 연골종에서 이차적으로 발생한 연골육종을 치험한 바 문헌고찰과 함께 보고하는 바이다. A case of Secondary Chondrosarcoma Arising from Solitary Osteochondroma of the Distal Femur Department of Orthopaedic Surgery, College of Medicine, DongGuk University Phil Hyun Chung M.D., Jung Su Hwang M.D., Suk Kang M.D., Yang Mln Kim M.D., Hyung Ho Oh M.D., Dong Ju Chae M.D., Jong Pil Kim M.D. Chondrpsarcoma is a malignant cartilage-forming tumor that grows slowly and metastasis of this tumor occurs in late stage. Secondary chondrosarcomas arising from a solitary osteocartilaginous exostosis are rare and those have a better prognosis than other chondrosarcomas, and they rarely metastasize. We present our experience with a case of secondary chondrpsarcoma arising in solitary osteochondroma of distal metaphysis of right femur with clinical details.

반복하중을 받는 철근의 부착 응력도에 관한 실험적 연구

정란,박현수,조동철 단국대학교 신소재기술연구소 1991 신소재 Vol.1 No.-

지진하중에 대한 철근콘크리트 구조물의 거동을 예측하기 위해 지금까지 진행하였던 많은 실험들이 단순증가 반복하중을 작용시키고 있다. 그러나 실제 지진에 의해 발생되는 하중은 불규칙 반복하중으로써 이전까지 관례적으로 행해졌던 규칙적인 단순증가 반복하중에 의한 실험결과가 얼마만큼 신빙성이 있는가를 검토할 필요가 있다. 본 연구에서는 지진하중에 대한 실험에서는 어떠한 하중을 가져야 실제 거동과 근사한 결과를 얻을 수 있는가를 예측하기 위하여 철근콤크리트 구조물의 구조적 취약부분인 보-기둥 접합부에 규칙적인 단순증가 반복하중과 불규칙 반복하중을 작용시켜 접합부의 부착응력도의 분포를 비교 분석하였다. The prediction and estimation of R/C structure behavlor subjected to earthquake type loading is partly based on the experimental results of the monotonically increased cyclic loading, rather than that of the irregularly increased cyclic loading. However, actual earthquake is typical random vibration. In this respect, comparing and analysing experimental test results of R/C specimens subjected to monotonically increased cyclic loading and irrcgularly increased cyclic loading, this study proposes the research direction of irregularly increased cyclic loading during earthquake.

서울시 소음공해 현황과 이에 대한 주민의 인식정도

정인희,이효수,김동수,김흥식 한국환경과학회 1997 한국환경과학회지 Vol.6 No.6

Nine districts in Seoul were chosen randomly and a questionnaire containing 23 questions was distributed to survey the perception of noise pollution by the citizens. The results were primarily analyzed to understand the perception of Seoul citizen as a whole, and then analyzed according to 4 demographic variables -district area, age, gender and occupation -to see if there were any possible relation between nonnoise variables and noise annoyance. Actual noise level data measured by the city government were used to compare quantified noise level with the surveyed people's perception. It was found that people consider road traffic noise to be the main source of noise pollution in Seoul and that most people have experienced annoyance in everyday life. Also it was verified that the responsibility for noise control should be on both city government and the individuals, but it was generally considered that very little effort is actually put into solving noise pollution from both groups. From the survey, it could be analyzed that demographic variables do affect people in the awareness of noise pollution, and that one's sensitivity and annoyance due to noise increase as one ages. From the study, it was concluded that noise pollution is not considered currently as a hazardous problem to most Seoul citizens, however specific noise reduction policies, especially regarding road traffic noise, should be put into practice in the near future.

문제만들기(problem posing)활동을 통한 수학의 학습 지도

정동권,박정수 仁川敎育大學校 科學敎育硏究所 1998 과학교육논총 Vol.10 No.-

In the mathematics education, problem posing has been noticed as a method to achieve the various objects of curriculum and as an object itself. That is, it is has been regarded as an efficient step to develop the ability of mathematical thinking and of problem solving. However, up to now teachers didn't take several advantages of problem posing in the mathematics classroom since they made mostly children solve the ready made and given problems in accordance with the fixed algorithm. In this study we have aimed to improve such a realistic circumstances of our mathematics education, and hence instructed children in the division of fractions by utilizing positively their problem posing activity. Subsequently we analyzed the result of the instruction, and made some overtures.

동기발전기 여자시스템용 고주파 PWM 컨버터 설계

장수진,류동균,원충연,이진국,배기훈,김수석 성균관대학교 2003 학술회의지원논문목록집 Vol.2003 No.-

A synchronous generator is equipped with an automatic voltage regulator(AVR), which is responsible for keeping the output voltage constant under normal operating conditions at various levels. The output voltage of Synchronous Generator is regulated constantly by field voltage control in excitation system. High frequency PWM converter (Buck converter) type excitation system for synchronous generator that can sustain proper output voltage level even at the fault condition happened. The proper operation of the proposed excitation system was verified through the simulations and the experiments.

복합식 히트펌프 설계를 위한 액체건조제 제습기의 성능 특성에 관한 실험적 연구

이수동,정진은,박문수 한국기술교육대학교 2004 論文集 Vol.10 No.2

A liquid desiccant for hybrid heat pump system undergoes various influences by several working factor. This paper presents the study of six options in related with the dehumidification rate and efficiency absorption in the dehumidification system. The effect of operating variables such as inlet solution concentration, inlet solution flow rate, inlet solution temperature, inlet air flow rate, inlet air temperature, and brine temperature was analyzed. The experimental dehumidifier has been designed to study the dehumidi- fication characteristics of the aqueous triethylene glycol(TEG) system. The performance characteristics of the absorption dehumidification system can be used effectively to save energy by reducing latent heat load. The result of this experiment can provide useful data for hybrid air conditioning system.

건물내장재(석고보드,합판)의 화재성능평가

김충환,김종훈,김운형,하동명,이수경 한국화재소방학회 2001 한국화재소방학회논문지 Vol.15 No.3

본 연구는 국내와 외국의 건물 내장재 화재성능평가방법을 고찰하고 국내에는 도입되지 않은 실대 화재 실험인 Room Corner Test를 국내 내장재중 석고보드와 합판을 대상으로 그 적용성을 위한 실험을 진행하였다. 현재 국내 내장재의 평가규정은 Bench-Scale Test에 의존하고 있으나, 미국, 일본 유럽등에서는 Room Corner Test를 적용한 실질적인 재료의 화재성능평가를 시행하고 있다. 실험 결과, NFPA 265에 의한 석고보드 및 ISO 9705에 의한 합판의 성능은 양호한 것으로 판단되었다. 현재 국내 내장재에 적용되는 등급분류의 평가방법은 재료의 실제 화재성능 평가에 한계가 있으므로 향후 Room Corner Test의 적용과 더불어 Bench-Scale Test 결과를 토대로 화재성능을 예측하는 화재모델을 이용하는 평가 방법의 도입이 필요하다. The fire performance evaluation methods in Korea and overseas for interior finish materials were analysed and tested with gypsum board and plywood by using room corner test not adopted by domestic code until now. The results of gypsum board (thickness: 8 mm) and plywood (thickness: 4 mm) applying NFPA 265 and ISO 9705 test respectively are satisfied the assessment criteria. To assess a actual fire performance and classify fore hazard levels for interior finish materials, room-corner test and flame spread models should be adopted in building code and fire code to overcome limitations of current bench-scale test method. Keywords : Fire performance evaluation, Room corner test, Gypsum board, Plywood

전류제어형 PWM컨버터를 이용한 동기발전기용 여자시스템에 관한 연구

장수진,류동균,서민성,김준호,원충연,이진국 성균관대학교 2003 학술회의지원논문목록집 Vol.2003 No.-

동기발전기 출력전압은 여자시스템의 계자전류 제어에 의해 일정하게 유지된다. 고주파 PWM 컨버터(전류제어모드 buck컨버더)형태의 여자시스템은 부하변동이 발생하였을 때 동기발전기의 계자전류를 제어하게 된다. 이 논문은 정상상태 및 과도상태에서의 안정화를 개선하기 위하여 여자시스템의 설계 및 실험에 대해 다루었다. 시뮬레이션 및 실험 결과는 제안된 여자시스템이 50kW 동기발전기의 DVR에 의해 응답시간이 개선되었음을 보여주었다. The output voltage of synchronous generator is regulated constantly by field current control in excitation system. High frequency PWM converter (current control mode buck conveter) type excitation system for synchronous generator is able to control exciter current when the load change happened. This paper deals with the design and evaluation of the excitation system for a synchronous generator to improve the steady state and transient stability. The simulation and experimental results show that the proposed excitation system is able to improve the response time by the DVR(digital voltage regulator) of 5O[kW] synchronous generator.

Cervical Headgear와 Anterior bite plate를 이용한 Ⅱ급 부정교합의 치험례

손동수,이상훈,장기택,박윤정 大韓小兒齒科學會 1995 大韓小兒齒科學會誌 Vol.22 No.2

The headgear is an extraoral appliance which used to distal movement of the teeth, inhibition of maxillary growth and reinforcement of anchorage. In case of treatment of Class Ⅱ malocclusion, however, it is not sufficient to simply restrict the horizontal growth of maxilla but to need treatment on mandibular retrusion. Generally, the combination theraphy of activator and headgear is conventional, but other study about combination therapy with other intraoral removable appliance is done. In this case, theatments were done by the combination therapy of headgear and anterior bite plate. The results were followed: 1. Reduction of SNA, upper lip to esthetic plane and lower lip to esthetic plane were observed. 2. 1 to FH plane angle was corrected. 3. Severe overbite, large overjet, and deep curve of spee was corrected. 4. Class Ⅱ molar relation was changed by class Ⅰ.

요구르트가 여자대학생의 변비에 미치는 임상적 연구

이서래,김화영,최삼섭,승정자,오명숙,김동재 이화여자대학교 생명과학연구소 1996 생명과학연구논문집 Vol.7 No.-

In order to study the prevalence of constipation among female college students in Korea and the effect of yogurt, 3,243 students in Seoul area were surveyed by questionnaires for the status of stool evacuation and 197 students with possible constipation were sample and fed apple yogurt II from Pasteur Dairy Company for 3-weeks period. Students of constipation amounted to a high ratio of 53.4%, which consisted of 13.4% in heavy constipation(1-2 times evacuation per week)and 40.0% in mild constipation(3-4 times evacuation per week)during the past one-year period. To 90 of heavy constipation and 107 of mild constipation students were fed 290ml of yogurt every morning for 3-weeks period and examined for the status of stool evacuation by subsequent questionnaires. Frequency of stool evacuation was significantly improved in 51.3% of the students after 1 week, 57.9% after 2 weeks and 60.4% after 3 weeks(p<0.05). The effect of improvement in stool frequency was greater in heavy group than in mild group through the 3-weeks period. The number of students who experienced the disappearance of inconvenience in evacuation after drinking the yogurt was 52.3% after 1 week, 72.1% after 2 weeks and 76.1% after 3 weeks. Discomfort such as stomach disorder and mild diarrhea during the drinking period was observed in 24% students and it appeared that a longer drinking period was needed for adaptation of digestive tracts. The number of students maintaining the improved stool frequency was 38.7% after 1 week and 37.6% after 1 month since discontinuing yogurt drinking. The number of students reverted to the previous habit of evacuation after discontinuing was 51.6% after 1 week and 63.5% after 1 month, which were not significantly different between heavy and mild groups(p>0.05).