방사선사진의 인덱스-순서 분석을 통한 치아경조직의 탈염화 검출

박동현,박영호,김경숙,박정훈,이기자,최삼진,최용석,황의환,박헌국 대한구강악안면방사선학회 2009 Imaging Science in Dentistry Vol.39 No.2

Purpose : The purpose of this study was to develop the radiographic technique for detecting the demineralization which is known as indication of dental caries. Materials and Methods : This technique was based on the comparing of multiple radiographs which was irradiated by multiple X-ray spectra. For the meaningful comparing, the multiple radiographs were reconstructed to the dosimetrically consistent images using a standard material. The difference of resulting images of same target with multiple spectra represents the difference of response of material as regards the spectra. Results : We have found about 10% of demineralization of dental hard tissues particularly in the proximal region through the analyzing of differences. Conclusion : Most intriguing thing in this investigation was that the method to analyze difference shows us to an anatomic structure of dental hard tissues even if absolute values of optical density were excluded during the procedures.

개에서 이중 결찰법을 통한 동맥관 개존증의 완치 예

윤헌영,정순욱,박희명,박철,정만복,김준영,한현정,황민,노병국,박상혁,장하영,박정윤 한국임상수의학회 2004 한국임상수의학회지 Vol.21 No.1

A ten months old, female Yorkshire terrier weighing 2.88 kg referred to veterinary teaching hospital of college of veterinary medicine, Konkuk University because of syncope, cough and dyspnea. First hematological and serum chemical test revealed thrombocytopenia, mild anemia, and increase of concentration of ALP (195 U/L). On 57 days later, second hematological and serum chemical test revealed polycythemia, increase of concentration of ALP (211 U/L), and Tchol (387 mg/dl). Right atrium enlargement, main pulmonary artery bulge and cardiomegaly (VHS = 11.5) were observed in radiographic findings. Ultrasonographic images showed both right and left ventricular dilation and turbulent flow between the descending aorta and the main pulmonary artery in color Doppler imaging. ECG showed left ventricular enlargement, SA block, and electrical alternant. Thoracotomy was performed through left fourth intercostal incision under isoflurane anesthesia. Patent ductus arteriosus was double ligated with 1-0 silk. Cough and dyspnea disappeared on 5 days after operation. Turbulent flow was not found in color doppler imaging of ultrasonography on 10 days after operation. Ten months later after the operation, syncope could not exist any more.

성인형 당뇨병에서의 심혈관 합병증과 지질대사와의 관계

박헌진,안정기,이종선,김영건 충남대학교 의과대학 지역사회의학연구소 1989 충남의대잡지 Vol.16 No.1

Hypwelipiswmia is commonly observed in the diabetics, especially with cardiovascular complications. We studied lipid profiles and cardiovascular complication in the 191 adult onset DM patients. The results are as follows: 1. The age distribution was from 24 years old to 82 years old. Male patients were 99 persons, famale patients were 92 persons. The mean disease duration was less than 2 years in the 77 patients, more than 5 years in the 79 patients. 2. Upon the classification between sexes, the mean age was 55±1(SEM) years in the male group, 53±1(SEM) years in the female group. The mean disease durtion was 6.4±1(SEM) years in the female group, longer in the male group (P<0.05). The triglyceride level was 210±16(SEM)㎎% in the male group, 214±13(SEM)㎎% in the female group. The fasting blood sugar level was 147±6(SEM)㎎/dl in the male group, 158±8(SEM)㎎/dl n the female group. The cholesterol level was 229±5(SEM)㎎/dl in the male group, 248±5(SEM)㎎/dl in the female group, higher in the female group (P<0.05). 3. The cardiovascurlar complicatioin (Hypertension, Myocardial infarction, Myocardial ischemia, Angina, Gangrene, Proliferative retinopathy) were present in the 60 patients from 191 patients. Hypertension was present in the 48 patients, and the most prevalent. The mean age and carrdiovascular complication were higher in the more than 5 years of mean disease duration group(mean age 57.99±1.14(SEM)㎎ year) than less than 5 years group(mean age 52.12±0.10(SEM)㎎ year) (P<0.001, P<0.01). 4. The mean disease duration (7.40±1.01(SEM) years), mean triglyceride levels(271±1.01(SEM)㎎%), and mean cholestrerol levels( 257±8㎎.dl) in the cardiovascularly complicated group were higher than those of non-complicated group (P<0.01). 5. The triglycerdie level was high in the obese group (230±14SEM㎎%) than non-obese group (184±15SEM㎎%) (P<0.05). The obese patients were more prevalent in the female group than male group significantly. 6. Considering obesity and cardiovascular complications, the triglyceride value was higher in the obese complicated group(300±30SEM㎎%) than obese non-complicated (197±14SEM㎎ %) or non-obese non-complicated (168±13SEM㎎ %) group (P<0.001). The cholesterol level was higher in the obese complicated group (267±10SEM㎎/dl) than obese non-complicated (230±5SEM㎎/dl) or non-obese non-complicated group(229±7SEM㎎/dl) (P<0.05). 7. Classifying upon insulin response pattern, the obese patients were found in the response pattern, low response pattern, flat type pattern(no response pattern) in the decreasing number of order (P<0.01). The cardiovascular complications were found in the low response group, response group, and flat type pattern (no response) in the decreasing number of order ( P<0.05). The combined cases of obesity and cardiovascular complications were found in the low response group, response group and flat type group(no response) pattern in the decreasing number of order (P<0.01). The mean disease duration was longer in the flat type group (no response) (4.48±0.6SEM years) than the response group(2.43±0.90SEM years) (P<0.05). The mean triglyceride value was higher in the response group (267.38±154.75SEM㎎%) than the flat type(no response group) (198.35±154.05SD㎎%) (P<0.05). So, we conclude that in the NIDDM, obesity control(die control, ideal body weight mainterice, and hyperlipidemia control) is essential for better DM control and cardiovascular complication control.

Effect of Mechanical Alloying on the Microstructural Evolution of Al60Cr30Si10 Alloys Processed by Spark Plasma Sintering

Jeong‑Han Lee,Ik‑Hyun Oh,Jun‑Ho Jang,Ju‑Hun Kim,Sung‑Kil Hong,Hyun‑Kuk Park 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.5

In this study, Al, Cr and Si fine powders were alloyed by planetary ball milling to investigate their microstructural evolution,following their mechanical alloying behavior. The formation of Al(Cr) supersaturated solid solution by the Cr grainsembedded in Al-matrix, which contributed substitutional structure is discussed in relation to their structural evolution inaccordance with the distortion of a crystal lattice. The compacts of Al–Cr–Si alloys were prepared by rapid sintering withina short time by dense consolidation above the density of 99.9% as the formation of intermetallics, except in the case of thedistribution of single-phases induced by the Al-melting. The formation behavior of intermetallics was dominated by dependenceon the structures of the milled-powder and subsequent sintering temperature. To estimate the consolidated behaviorsof compacts, various approaches derived from TEM and XRD analysis were taken to obtain microstructural evidences ofthe inter-diffusion, following the presence of thermally stable intermetallics.

통합교육에서의 장애유아의 적응기술에 대한 교사의 인식

박정훈,강대옥,박재국 한국특수아동학회 2003 특수아동교육연구 Vol.5 No.1

본 연구는 통학교육에서 장애유아의 적용기술에 대한 교사의 인식을 조사하기 위한 것으로 통합교육 프로그램을 준비하고, 실제적인 교육을 수행하는데 필요한 기초자료를 제공하고자 하였다. 부산시 유아교육기관의 일반교사 97명과 특수교사 60명을 대상으로 통합교육에 필요한 적용기술에 대한 인식을 설문지를 이용하여 조사한 결과 다음과 같은 주된 결론을 얻었다. 첫째, 통합교육에서 요구되는 적응기술에 대한 인식에서는 일반교사와 특수교사 사이에 차이가 없었으나, 하위 영역에서 특수교사들이 일반교사보다 적응기술의 중요성을 높게 평가하고 있다. 둘째, 통합교육에서 요구되는 적응기술의 하위영역에서 특수교사들은 집단활동 참여기술을 가장 중요하게 인식하고 있으나, 일반교사들은 독립생활기술을 가장 중요하게 인식하고 있다. 셋째, 장애유아 적응기술에 대한 교사변인에 따른 인식차이에서 통합경험이 없는 교사들이 적응기술을 중요하게 인식하고 있으며, 특수교육관련 연구경험이 없는 교사가 연수경험이 있는 교사보다 적응기술을 더 중요하게 인식하고 있다. 넷째, 성공적인 통합교육을 위한 교사의 의견에서는 교사의 긍정적 인식 및 태도를 가장 중요한 요인으로 인식하고 있으며, 학부모의 긍정적인 인식과 일반유아의 이해도 주요하다고 인식하고 있다. n This study aimed to determine teachers recognition of the adaptation skills of handicapped children for mainstream education and to provide basic materials for the successful execution of the programs to be prepared for mainstream education and actual mainstream education. This study considered 97 preschool teachers and 60 special teachers who were selected using random sampling, in Busan Metropolitan City. Questionnaires were distributed and collected, with responses reviewed and analyzed using SPSS Win 10.0. Results show no significant difference in the recognition of general adaptation skills of handicapped children required in mainstream education between special teachers and preschool teachers. In contrast, there is difference between the two groups in the sub-spheres of adaptation skills, in which spheres the importance of adaptation skills was more highly regarded by special teachers in the actual kindergarten education than ordinary kindergarten teachers thought. On the other hand, special teachers valued skills of participating in group activities the most in the sub-spheres of adaptation skills required in mainstream education while preschool teachers prioritized independent skills. To narrow such difference in recognition, correct understanding of and active exchange of information in mainstream education should be developed. In addition, teachers without experience in mainstream education were found to require a higher level of adaptation skills from handicapped children compared to teachers with experience in mainstream education. Likewise, teachers without educational training valued adaptation skills more compared to teachers with educational training. Both special teachers and preschool teachers expected a higher level of adaptation skills from handicapped children compared to mainstream education teachers. This suggests that special teachers or teachers without experience in mainstream education demanded a higher level of adaptation skills than actually necessary in mainstream education. The recognition of teachers also varied depending on the educational institution they belong. Finally, teachers considered the positive recognition and attitude of teachers, positive recognition of students parents, and understanding of children as mojor contributory factors to successful mainstream education.

인공 치아우식 발생 모델에서 디지털 방사선 공제술을 이용한 인접면 치아우식증의 진단

박정훈,최용석,황의환,이기자,최삼진,박영호,김경숙,진현석,홍경원,오범석,박헌국 대한구강악안면방사선학회 2009 Imaging Science in Dentistry Vol.39 No.1

Purpose : The purpose of the experiment was to evaluating the diagnostic ability of dental caries detection using digital subtraction in the artificial caries activity model. Materials and Methods : Digital radiographies of five teeth with 8 proximal surfaces were obtained by CCD sensor (Kodak RVG 6100 using a size #2). The digital radiographic images and subtraction images from artificial proximal caries were examined and interpreted. In this study, we proposed novel caries detection method which could diagnose the dental proximal caries from single digital radiographic image. Results : In artificial caries activity model, the range of lesional depth was 572-1,374 μm and the range of lesional area was 36.95-138.52mm². The lesional depth and the area were significantly increased with demineralization time (p<0.001). Furthermore, the proximal caries detection using digital subtraction radiography showed high detection rate compared to the proximal caries examination using simple digital radiograph. Conclusion : The results demonstrated that the digital subtraction radiography from single radiographic image of artificial caries was highly efficient in the detection of dental caries compared to the data from simple digital radiograph.

Rapid Consolidation of WC‑ZrSiO4 Hard Materials by Spark Plasma Sintering: Microstructure, Densification, and Mechanical Properties

Jeong‑Han Lee,Ik‑Hyun Oh,Ju‑Hun Kim,Sung‑Kil Hong,Hyun‑Kuk Park 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.9

Densely consolidated WC-based hard materials with 5–20 vol% ZrSiO4was fabricated by spark plasma sintering at 1400 ℃ ata constant heating rate of 70 ℃/min−1. To achieve mechanical alloying of WC-ZrSiO4, planetary ball milling was carried outfor 12 h, during which the brittle-brittle components (WC-ZrSiO4) became fragmented and their particles became refined. Itwas observed that certain, specific, non-isothermal sintering kinetics, such as apparent activation energy, sintering exponents,and densification strain, affected the densification behavior. The evolution of phase structure from powder to compact wasfound to be related the lattice distortion and micro-strain in the basal planes of WC. By examining the mechanical propertiesof the samples, it was that the added zircon content leads to enhanced fracture toughness (12.9 MPa m1/2) owing to thepresence of WC-ZrSiO4 in the cemented carbide. In fact, the microcrack propagation of the fracture passed through zirconfrom a transgranular to a ductile component (fcc) where the crack tips could be absorbed.

스포츠 센터 회원들의 서비스에 대한 만족도 및 지속참가에 영향을 미치는 요인 분석

박정훈 한국스포츠리서치 2004 한국 스포츠 리서치 Vol.15 No.4

This is a study about dissatisfaction caused by the relationship between the personal character of the users of sports facilities and the different requirement of sports. And adherence to exercise program among sports center members. A questionaire has been completed after analysis of the result from the preceeding study and pre-examination The reliability of the source has been verified prior to the study. The subjects in this study were 346 people who were selected by random sampling from 5 sports centers in Kyonggi Province at Suwon & Anyang. The collected data were handled by reliability analysis, t-test, one-way ANOVA, Pearson correlation and stepwise multiple regression. The findings of this study were as follows; The result showed, most of sports center members felt that facilities using fees were neither satisfaction nor dissatisfaction so, this members need to increase the instructor's and employee's polite service, program development etc, One of results employee's polites analysis showed that it wasn't positive satisfaction, this is very important thing for us, because sports centers were some kind of service management but this result wasn't positive it. One of important showed results were unless leaders skills or teaching, information employee's service, also members most needed to not to exercise facilities, convenient items for exercise. For Instance perking lot, shower room, rounge etc, all round comfortable system; will arise spats center members satisfaction. Member's financial and degree of sport Involvement are important factors influence to exercise program, among sport center members, while members emotional situation has no Influence on the exercise adherence. The degree of the satisfaction with program is the most strongly influencing sport socialization factor on exercise adherence among sports centers. The result showed sports centers service should be kept steadily and the establishment of strategic sports plan So we should make on operation strategy for current situation of ploblem analysis future marketing strategy followed by an program action.

EPC 주강품의 Carbon Pick-up 현상

박익민,김대석,김정훈 한국주조공학회 2005 한국주조공학회지 Vol.25 No.1

Influence of Phase Composition in TiAlSiN Hard Coatings on the Evolution of Structure and Mechanical Properties

Jeong‑Han Lee,Ik‑Hyun Oh,Jun‑Ho Jang,Ju‑Hun Kim,Sung‑Kil Hong,Hyun‑Kuk Park 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.3

The aim of this study is to investigate the structural evolution and mechanical properties of TiAlSiN coatings when processedby the arc ion plating method. To form a hard coating, Ti, Al, and Si powders were mechanically alloyed by planetary ballmilling; the powders were then densely compacted during a rapid sintering process into a ternary system coating, i.e. TiAlSi. The evolution of the structural phase from a powder to a compact material is dominated considerably by phase states suchas a supersaturated solid solution or intermetallic compounds. In the case of coating layers, the factors that determine thestructural evolution are associated with the phase stability of the nano-crystalline structure that in turn is associated withthe Ti/Al composition ratio. Motivated by this, we performed experiments to investigate the distribution of microstructures;the material’s binding energy, quantitative properties, transformation of crystal structure, and distribution of amorphous/crystalline were all recorded. In particular, the relationship between the physical and chemical properties during the coatingprocess is considered to be the dominant factor controlling the orientation and morphology of that zone (1, T, and 2). TheTiAlSiN coating layer was found to have hardness above 45 GPa and an adhesion above 100 N. In other words, understandingthe evolution and structure of TiAlSin helped us to produce a material with excellent properties that can be used as a hardcoating. Specifically, these properties were induced by a grain refinement of the nano-crystalline structure that correspondsto an increase in the silicon nitride contents.