직업 및 진로교육을 위한 멀티미디어 학습자료 개발

김종철 단국대학교 1999 敎育論叢 Vol.14 No.-

STS3 합금강의 절삭력에 관한 연구

金鍾喆,安道熙 충주대학교 산업대학원 1999 大學院論文輯 Vol.1 No.-

The reported investigations aimed at clarifying cutting characteristics interacting with cutting condition,when machining alloy steel STS 3 using KT250 more useful in the mechanical metallurgical field. An extended measurement series and calculations were conducted on cutting test changing feed rake, cutting speed and depth of cut. The cutting resistance in measured according to the four classified conditions changed by tool dynamometer mounted on a lathe. The cutting characteristics and optimized conditions are presented, explicating interrelation between estimated cutting force, tool wear and surface roughness.

백서에서 실험적 치아이동시 치조골 흡수에 미치는 Bisphosphonate의 영향 : 생화학적 및 조직학적 관찰 Biochemical & Histological Observations

최진휴,김종철 대한치과교정학회 1999 대한치과교정학회지 Vol.29 No.1

백서에서 실험적 치아 이동시 bisphosphonate가 파골세포의 형성에 미치는 영향과 골 흡수 억제기전을 규명하고 독성유무를 알아보고자 하였다. 체중 260-350g의 웅성 백서 87마리를 정상군(장치비장착 + 0.9% NaCl), 대조군(장치장착 _ 0.9% NaCl) 및 장치장착후 bisphosphonate 투여군(0.8mg, 4 mg, 20 mg, 및 100mg/kg) 으로 분류하였다. 상악 좌측 제1대구치를 근심으로 치아이동이 일어나도록 50-70g의 교정력을 가하고, 교정장치 장착후 1일, 3일 및 7일째에 혈청 acid phosphatase와 lactate dehydrogenase (LDH)의 활성도를 측정하고, 또한 제1대구치를 포함한 상악골일부에서 파골세포수 및 골흡수 정도를 조직학적으로 관찰하여 다음과 같은 성적을 얻었다. 1. Acid phosphatase 활성도는 장치후 1일째와 3일째에 대조군과 bisphosphonate 투여군에 서 모두 정상군에 비해 2-3배 높았으나, 7일째에는 정상군과 유의한 차이를 보이지 않았다. 2. LDH활성도는 bisphosphonate 4 mg과 20mg/kg 투여군에서 전 실험기간에 걸쳐 증가된 양상을 보였으나 0.8mg과 100mg/kg 투여군에서는 유의한 차이를 나타내지 않았다. 3. 골흡수는 장치후 1일째에 대조군과 bisphosphonate 투여군에서 모두 관찰되지 않았으나, 3일 이후에 나타난 7일째가지 지속되었다. Bisphosphonate 4, 20 및 100mg/kg 군에서의 골흡수정도는 3일째에는 대조군에 비해 미약하였으나 7일째에는 대조군과 유사하게 나타났다. 4. 파골세포는 1일째에 대조군이나 bisphosphonate 투여군 모두에서 거의 관찰할 수 없었다. 3일째에 대조군에서는 파골세포가 다량 출현하였으나 bisphosphonate 투여군에서는 약물의 용량이 증가함에 따라 감소하여 나타났다. 이상의 결과로 실험적 치아이동시 파골세포의 형성억제가 bisphosphonate에 의한 골흡수억제기전이 아님을 알 수 있었고, bisphosphonate는 투여량이 증가에 따른 뚜렷한 세포독성은 관찰되지 않았으며, 골흡수 억제효과를 지속시키기 위해서는 약물이 반복적으로 투여되어야 할 필요가 있음이 시사되었다. This study was performed to examine the effect of bisphosphonate, an inhibitor of bone resorption, on the formation of osteoclast and bone resorption during experimental tooth movement. Whether bisphosphonate has a cytotoxity in high dose was also examined. Eighty-seven male Sprague-Dawley rats, weighing 260-350g, were classified into normal (no appliance + 0.9% NaCl), control (appliance + 0.9% NaCl) and four bisphosphonate-treated (appliance + 0.8, 4, 20, or 100mg/kg) groups. The maxillary left first molar was moved mesially with the tipping movement using 5-70g of force. Bisphosphonate(etidronate disodium) was injected intraperitoneally with a dose of 0.8, 4, 20 or 100mg/kg simultaneously with the application of the orthodontic force. They were killed at day 1, 3 or 7 after the application of the orthodontic force. The activities of serum acid phosphatase and lactate dehydrogenase (LDH) were assayed, and osteoclasts and the degree of bone resorption were examined histologically. The results obtained were as follows: 1. Acid phosphatase activities were significantly higher in the appliance groups, both control and bisphosphonate-treated (4, 20, and 100 mg/kg) groups, at days 1 and 3 than these in normal. At day 1, bisphosphonate-treated(4, 20mg/kg) groups showed even higher acid phosphatase than control. However, at day 7, no significant difference was noted between the control and bisphosphonate-treated groups. 2. LDH activities in the 4, 20mg/kg bisphosphonate-treated groups were increased during the experimental periods examined, but there were no significant differences in the 0.8, 100mg/kg bisphosphonate-treated groups. 3. There was no bone resorption at day, 1, but severe bone resorption was observed at days 3 and 7 in the control. Bone resorption was reduced by bisphosphonate-treatment at day 3. Bone resorption observed at day 7 was similar between the control and bisphosphonate-treated groups. 4. Few osteoclasts were observed at the alveolar bone in the control and bisphosphonate-treated groups at day 1. At day 3, numerous osteoclasts were shown in the control, the degree of which was reduced in bisphosphonate-treated groups. These results suggest that the inhibition of the osteoclast formation was not the mechanism of bone resorption by the bisphosphonate-treatment during experimenal tooth movement. There was no distinct cytotoxicity with a high dose of bisphosphonate. And the drug should be administrated repeatedly to maintain the inhibitory effect of bone resorption.

제1급 부정교합 환자에서 치료전후 PAR지수와 두부방사선계측치의 변화

김현혜,이기헌,김종철 대한치과교정학회 1999 대한치과교정학회지 Vol.29 No.2

제 I급 부정교합 환자에서 PAR 지수가 교정치료기간 및 측모두부방사선 계측 항목과 관계 가 있는지를 규명하고자 100명의 교정 환자의 치료 전후 석고모형에서 PAR지수를 구하고, 측모두부방사선사진에서 12개의 계측치를 측정하여 분석한 후 다음과 같은 결과를 얻었다. 1. 치료 기간은 발치 여부 및 치료전 PAR 지수와 상관관계를 보였다. 2. ANB, FMA, FMIA,IMPA는 치료전 PAR 지수와 치료전 측모두부방사선 계측치에서 순 상관관계를 보였다. 3. 1 to EP는 치료후 PAR지수와 치료후 측모두부방사선 계측치에서 순상관관계를 보였고 1 to EP는 역상관관계를 보였다. 4. 1 to SN, IIA, 1 to FP는 % PAR와 치료전후 측모두부방사선 계측치의 변화량과의 관 계에서 순상관관계를 보였고, FMA, FMIA, WITS, UL은 역상관관계를 보였다. 이상의 결과는 석고모형상의 치아관계에서 측정한 PAR 지수가 측모두부방사선 계측치 중 상하 전치와 관련된 항목과 연관이 있으며, 제 I급 구치관계를 보이는 환자중 ANB 값이 크고 hyperdivergent한 안모를 갖는 경우 치료전 PAR 지수가 큰 경향을 나타냄을 시사하였다. The purpose of this study was to evaluate the relation between the treatment duration and cephalometric measurements and the PAR index in Class I malocclusion patients. In 100 Class I malocclusion patients. PAR score and cephalometric measurements were taken from study model cephalometric radiographs and analyzed statistically. The results of this study were obtained as follows: 1. Treatment duration was correlated with extraction and pre PAR index. 2. ANB, F MA, FMIA and IMPA exhibited positive correlation between pre PAR index pretreatment cephalometric measurements. 3. 1 to FP exhibited positive correlation between post PAR index and posttreatment cephalometric measurements and 1 to FP exhibited negative correlation. 4. 1 to S N, IIA and 1 to FP exhibited positive correlation between % PAR reduction and the change of cephalometric measurements and FMA, FMIA, WITS and UL exhibited negative correlation. The results of this study indicate that PAR index taken from study model related with items concerned with upper and lower incisors, and there are the tendency that pretreatment PAR index are larger in the patients with large ANB value and hyperdivergent face.

브라켓 간접부착시 레진 베이스의 재료에 따른 전단결합강도와 파절양상 비교

전만배,황현식,김종철 대한치과교정학회 1998 대한치과교정학회지 Vol.28 No.2

본 연구의 목적은 브라켓 간접부착술식에서 레진 베이스의 재료에 따른 전단 결합강도와 파절양상을 비교해 봄으로써 광중합형 레진 베이스 사용의 타당성을 평가해보는데 있다. 소의 하악 중절치를 포매하여 만든 시편의 석고 모형에 화학중합형 레진 접착제인 Excel과 광중합형 레진 접착제인 Light-Bond 및 열중합형 레진 접착제인 Therma Cure를 이용하여 금속 브라켓을 위치시킨 후 transfer tray를 사용하여 시편에 옮겨 부착한 다음 만능물성 시험기를 이용하여 전단결합강도를 측정하고, 파절양상을 관찰하여 다음과 같은 결과를 얻었다. 1. 평균 전단결합강도가 화학중합형 레진 베이스를 사용한 군에서 154.20±35.53 kg/㎠로 나타났으며, 세군간에 유의한 차이가 없었다(P>0.05). 2. 접착제 잔류지수를 통하여 파절양상을 비교 관찰한 결과 세 군간에 유의한 차이를 보이지 않았다(P>0.05). 이상의 실험결과는 브라켓 간접부착술식에서 레진 베이스의 재료로 화학중합형, 열중합형 레진과 함께 광중합형 레진도 사용될 수 있음을 시사하였다. The purpose of this study was to evaluate the propriety of making use of light-cured resin base in indirect bracket bonding technique by study of shear bond strength and failure patterns according to the material of resin base. Metal brackets were bonded to the stone models of specimens involving bovine lower incisor with chemical-cured(Excel), light-cured(light-Bond)and thermal-cured(Therma-Cure)resin. They were transferred to the specimens and bonded using sealant. The shear bond strength was tested on Instron. After bracket removal, the bracket base was examined and assessed with the adhesive remnant index(ARI), The result were as follows: 1. No significant differences in shear bond strength were found among the three groups(P>0.05). 2. No significant differences in ARI score were found among the three groups(P>0.05). The above results suggest that light-cured resin base in addition to chemical-cured and thermal-cured resin bases is useful in the indirect bonding technique.

개정된 예방적 항생제 투여에 따른 선천성 심장질환 환자의 치과치료

정미영,김종철 大韓小兒齒科學會 1991 大韓小兒齒科學會誌 Vol.18 No.2

Patient with congenital heart disease are susceptible to bacteral endocarditis, and bacteremia following dental procedures may lead to bacterial endocarditis in these patients. Therefore prophylactic antibiotics are recommended for patients with congenital heart disease who are undergoing dental procedures. In 1984,American Heart Association revised guidelines for a prophylaxis against bacterial endocarditis and these include a large loading dose of antibiotics with a single postoperative booster. For most patients, oral penicillin is recommended and for those allergic to penicillin, erythromycin is preferred antibiotic. This report presents two cases of dental treatment of patient with congenital heart disease under the most recent American Heart Association recommendations and for antibiotic prophylaxis.

신축공동주택내 실내유해공기오염물질(HAPs)의 건강위해성평가

김종철,김윤신,노영만,홍승철,이철민,전형진,Kim, Jong-Cheol,Kim, Yoon-Shin,Roh, Young-Man,Hong, Seung-Cheol,Lee, Cheol-Min,Jun, Hyung-Jin 한국환경보건학회 2007 한국환경보건학회지 Vol.33 No.1

This study accomplished to grasp the present condition of HAPs and to examine efficiently carcinogenic and non-carcinogenic health effects through health risk assessment in new apartments from June, 2004 to May,2005. Moreover, we performed uncertainty analysis by Monte-Carlo analysis to control uncertainty of exposure factors. The major results obtained from this study were as follows. Firstly, cancer risk of formaldehyde for male was $1.67{\times}10^{-5}$ in CTE in point estimation. Cancer risk of formaldehyde was showed $2.94{\times}10^{-3}$ in RME that applied worst case used results of 95 percentile in point estimation. It exceeds $10^{-6}$ of guide line in US EPA. Moreover, cancer risks of formaldehyde for female were $3.98{\times}10^{-5}$ in CTE and $3.93{\times}10^{-3}$ RME. Secondly, every hazard index for non-carcinogenic pollutants was less than 1 of permitted standards in CTE. However, in RME of male, hazard indexes of 1,2-Dichloropropane and Toluene were 1.3 and 2.0, respectively. Hazard indexes of 1,2-Dichloropropane and Totuene for female in RME were 1.7 and 2.6, respectively.

A study on recreation and leisure habits of Korean University students for the interrelation to life satisfaction.

김종철,김준희,이예승 한국여가레크리에이션학회 2008 한국여가레크리에이션학회지 Vol.32 No.4

The purpose of the present study is to research and examine specifically the relationship that exists between leisure time and life satisfaction experienced among Korean University students. This study asks three questions. Firstly,” What are the degrees of leisure participation, leisure satisfaction and life satisfaction of male and female college students in Korea?” Secondly, “What are the differences of leisure participation and life satisfaction of college of college students in Korea in relation to specific factors that impact this relationship? And thirdly, “How, if indeed it is, is the individual’s self-esteem interrelated to leisure time and life satisfaction of college students in Korea?” The method of this study is through conduction of review of available peer reviewed literature. According to the college students’ participation type and extent of leisure activity, college satisfactions are increased, through increased leisure participation. Therefore, the quality of life in college students is enhanced directly. Also, Findings of this study show that it is the perception of the student in relation to accomplishment, time management skills and other relating factors of self-perception that greatly influence the enjoyment of leisure time by the college aged student in Korea more so than any other societal, governmental, health-related, financial, or any other known factor that causes an impact on leisure and as well that the self-perception of the student which colors the experience of leisure colors the experience of satisfaction in life as well.

韓國 高等敎育政策의 歷史的展開(1945∼75)

金鍾喆 東亞大學校 敎育大學院 1975 敎育大學院 論文集 Vol.2 No.-

Hurler증후군 환아의 치의학적 소견에 대한 증례보고

박정삼,한세현,김종철 大韓小兒齒科學會 1995 大韓小兒齒科學會誌 Vol.22 No.2

Hurler syndrome is a disturbance of mucopolysaccharide metabolism exhibiting a variety of classic clinical features. This disease is the prototype and the most common component of mucopolysaccharidosis. We are reporting in this paper on a 4-year and 8-month old boy with Hurler syndrome. The dental findings are as follows; 1. Large head, prominent forehead, broad saddle nose and wide nostrils, hypertelolism, puffy eyelids, short neck, wheezing sound at breathing, flexion contractures, claw hands, mental retardation, dwarfism were observed. 2. Anterior openbite (enlarged tongue), spacing in lower anterior region, mouthbreathing, thick lips, shortening and broadening of the mandible were observed and the shape of the teeth are normal 3. Abnormal tooth size, delayed eruption and gingival hyperplasia were not observed.