지리산국립공원 내 산림관리에 관한 전문가 인식 조사

김동현 ( Dong Hyeon Kim ),김의경 ( Eui Gyeong Kim ),박상병 ( Sang Byeong Park ),이정환 ( Jeong Hwan Lee ) 한국산림과학회 2010 한국산림과학회지 Vol.99 No.4

This study carried out the recognition of appropriate forest managements and directions in Jirisan National Park. For this purpose, we undertook interview survey about the recognition of forest management in Jirisan National Park from ecological and forest research fields` experts. From the statistical analysis results, it was founded that the difference among respondents` types was detected about recognition of forest management in National park. However, all the respondent types recognized that the forest management in National park is essential. So the forest management in national park by forest experts and relevant institutions are revealed needed.

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.

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.

측두하악관절 내장증에서의 관절원판의 형태 및 골 변화에 관한 연구

박철우,황의환,이상래 대한구강악안면방사선학회 2001 Imaging Science in Dentistry Vol.31 No.1

Purpose : To investigate bone and disc configuration on MR images in internal derangement related to age. Materials and methods : MR images of 150 TMJs in 107 patients were analyzed to determine the morphologic changes. Two groups were distinguished to be correlated with age. Group 1 consisted of TMJs that were diagnosed as having anterior disc displacement with reduction (ADDwR), and Group 2 consisted of TMJs that were diagnosed as having anterior disc displacement without reduction (ADDwoR). We assessed the configuration of the articular disc, degree of anterior disc displacement, and osseous changes of TMJs. Results : The third decade (83 of 150 joints) was most frequent in this study. In the ADDwR group biconcave discs was most frequent at all ages except fifth decade, but in the ADDwoR group deformed discs was most frequent at third and forth decades. In the ADDwR group slightly displaced discs was most frequent at all ages, but in the ADDwoR group severely displaced discs was most frequent at second decade, and the degree of disc displacement was increased with aging over 30 years of age. TM joints showed osseous changes in 17% of the ADDwR group, and in 30% of the ADDwoR group. MR findings of osseous changes of the TMJ were not found to be significantly correlated with age. Conclusion : The prevalence of deformation of disc, displacement of disc, and osseous changes of TMJ was higher in the ADDwoR group than in the ADDwR group. MR findings of disc configuration and degree of disc displacement were found to be correlated with age.(Korean J Oral Maxillofac Radiol 2001;31:9-16)

방사선조사가 당뇨 백서의 치주조직에 미치는 영향

박동신,황의환,이상래 대한구강악안면방사선학회 2005 Imaging Science in Dentistry Vol.35 No.3

Purpose : To observe the histopathological changes in the periodontal tissues of mandibular molars in streptozotocin-induced diabetic rats after irradiation. Materials and Methods : The male Sprague-Dawley rats weighing approximately 250 gm were divided into four groups: control, diabetes, irradiation, and diabetes- irradiation groups. Diabetes mellitus was induced in the rats by injecting streptozotocin. Rats in the control and irradiation groups were injected with citrate buffer only. After 5 days, the head and neck region of the rats in irradiation and diabetes irradiation groups were irradiated with a single absorbed dose of 10 Gy. All the rats were sacrificed at 3, 7, 14, 21, and 28 days after irradiation. The specimen including the mandibular molars were sectioned and observed using a histopathological method. Results : In the diabetes group, osteoclastic activity was observed in the alveolar bone and the root throughout the period of experiment. Also, osteoblastic and fibroblastic activities were markedly decreased. In the irradiation group, the osteoclasts were observed in the alveolar bone and the dilated capillaries were increased in the early experimental phases. However, vigorous osteoblastic activity was noted in the late experimental phases. In the diabetes-irradiation group, osteoclastic activity in the alveolar bone and the root was observed in the early experimental phases. However, there were no resorption and osteoblastic activity in the alveolar bone and the root in the late experimental phases, and obvious atrophic change of fibrous tissues was noted. Conclusion : This experiment suggests that osteoblastic activity was caused by irradiation in the late experimental phases, but atrophic change of the periodontal ligament tissues was induced after irradiation in diabetic state.

Polypyrrole electrode Modified With Copper Bis(4-vinyl-4'-methyl-2,2'-bipyridine) Bis(perchlorate)

박의환 慶山大學校 1993 論文集 Vol.11 No.1

1. SEM micrographs of polypyrrole films Fig.3a and Fig.3b are SEM micrographs of the polypyrrole films grown on NBR-treated platinum electrode and on bare platinum electrode respectively. Inspection by SEM revealed that a polypyrrole film grown directly on platinum substrate showed a rather compact structure. In contrast, a polypyrrole film formed with the aid of NBR prepolymer had rough, porous, and somewhat linearly well-oriented structure. This well-oriented and porous structure is expected to be a favorable situation for the implantation of another conducting polymer. Fig.4 show an SEM micrograph of a polymer (host) film deposited in the presence of NBR and with perchlorate anion as doping agent that was further treated by electropolymerization of copper bis(4-vinyl-4'-methyl-2,2'-bipyridine) bis(hexafluorophosophate) (guest). The image is intended to allow distinction of the latter since it forms the larger granules that are clearly distinguishable in the micrograph. The quantities of host and guest polymer deposited were 0.65 and 0.39 coulombs cm-²and this ratio, which is too high for other purposes, was used only to make identification of each polymer location easier. 2. Cyclic voltamrnogram of various films Fig.5 is a cyclic voltammogram of the elctropolymerization of polypyrrole on NBR-teated platinum electrode. But this voltammogram was produced from the potential scan at range of -1.0-0.9 V instead of the constant potential to see the process of the growth of film during eletrolymerization. The oxidation peak potential (Epa) of the first cycle is 0.07 V and the reduction peak potential (Epc) is -0.21 V, but those of 30th cycle are 0.06 V and -0.19 V respectively. The differences between each peak potentials are 0.01 V and 0.02 V. This means that the oxidation peak potential was increased and the reduction peak potential was decreased slightly with cycles. This can be thought as that the internal resistance has increased as the length of polymer elongated and the small differences reveal a good reversibility. Fig.6 is a cyclic voltammetric profile of film by the implanting electropolymerization of copper bis(4-vinyl-4'-methyl-2,2'-bipyridine) bis(perch1orate) at a polypyrrole electrode, which was pretreated with NBR and prepared with hexafluorophosphate as dopant anion, in acetonitrile solution containing 0.1 M TBAP. The sweep range was 0∼-1.5 V and scan rate was 100 m/Vs. Every two peaks for oxidation and reduction are -0.250 V and -0.437 V, -0.375 V and -0.50 V respectively. From the successive experiments" the formers of each pair are confirmed for the hexafuorophosphate ion and the latter for perchlorate ion. Fig.7 presents cyclic voltammograms for polypyrrole doped with hexafluorophosphate ion (dashed line) and for the polymer doped with poiy copper bis(4-vinyl-4'-methyl-2,2'- bipyridine) bis(perch1orate) (solid line). As can be seen, the peak potentials for polypyrrole alone are 0.05 V and 0.35 V. For the polypyrrole implanted with the guest polymer the values for the polypyrrole host are 0.205 V and -0.325 V and for the guest they are 1.10 V and 0.56 V. These last two values correspond to oxidation and reduction precess, respectively. It is clear from these voltammetric responses that when the guest polymer is implanted, the redox profile of the electrode is greatly improved so that the capacity of charge storage can be greatly increased. The optimal quantity of electropolymerized polypyrrole was investigated in previous paper9) and the result was about 0.64 coulombs cm-²for the maximum conductivity. Table 1 presents resulting conductivities and doping levels of polypyrrole f i l m doped with poly copper bis(4-vinyl-4'-methyl-2,2'-bipyridine) bis(perch1orate) with various mixing ratio and they are plotted at Fig.8. And the doping levels were determined from Hall experiment and the coulometric integration of reduction wave in cyclic voltammogram. The resulting plot is Fig.9. From these results it can be concluded that the incorporation of poly copper bis(4-vinyl-4'-methyl-2,2'-bipyridine) bis(perchrorate) within the range of 10 -12 % into polypyrrole films significantly enhances the electrochemical properties of the resulting material.

2000년 제27회 시드니 올림픽 유도경기 대비: 세계 여자 우수선수들의 개인별 국제경기 기술 특성에 관한 연구

김의환,박순진,김관현,김도준,안병근,정훈,김미정 용인대학교 무도연구소 2000 武道硏究所誌 Vol.11 No.1

The purpose of this study was to analyze the competition techniques traits and of international contest levels each category individual scoring - losing techniques of world elite judokas who. were awarded in the international judo tournaments (I,J.T.) (part 1: ∼O.G'%, part 2 :from O.G'% to July ,2000), and who are expected to participate in the 27th Olympic Games(O.G.) Sydney 2000 to prepare the 27th O.G, which will be held from 16. to 22 September, 2000 at Exhibition Center, Darling Harbour, in Sydney, Australia. The records of the results and contents of competition were obtained out of 97 for women I.J,T., world elite judokas. To decide individual contest levels, groups were devided into 3(A,B,C)groups and points were graded by 3 ways. The I.J.T. that were devided into 3 groups are shown in the table 1.

유도 어깨로메치기의 운동학적 특성분석

김의환,김규수,김성섭,박중제 龍仁大學校 武道硏究所 2001 武道硏究所誌 Vol.12 No.1

The purpose of this study was to analyze the kinematic variables when performing Kata-guruma in judo. Yong-In University judo demonstration squad was filmed (30frames/sec.) on 16mm video camera on performing of Kata-guruma in judo. Kinematic variables analyzed here include time, angle and center of gravity. The mean values and the standard deviations for each variables were obtained and used as basic factors for examining characteristic of Kata-Guruma motion. The result of this analysis are ads following. 1) Angle variables From Kumikata to 1st stage in KP, the angle of right elbow in Kata-Guruma was decreased, to 2nd phase and air phase were increased slightly. Lefe elbow angle of Tsukuri motion was decreased from 1st stage in KP to air motion were increased. Kuzushi of right shoulder angle was decreased, Tsukuri of right shoulder was increased, air posture in Kake phase was increased, Kuzushi of left shoulder angle was increased and Tsukuri of left shoulder angle was decreased continually. Both angle of hips were decreased in 1st stage in KP phase. From 2nd stage in KP to air motion were increased slightly. Both angle of Knees were decreased in 1st Kake phase, from 2nd stage KP to air motion were increased again. Left arm obstructs the center of gravity of opposite, extends in order to set the body, and flexes in other to fling the body of the shoulder. Right arm was flexed on order to let the arm in between legs, and flexes on Kake motion and was extended in other to fling the body of the shoulder. According to result of angle variables, deflection of the subject A was of small quantity, and both subject A and B were fixed in view of subject B.

유도 양팔업어치기 동작 시 몸통 트위스트각 분석

김의환,박순진,강선영,정재욱 龍仁大學校 武道硏究所 2002 武道硏究所誌 Vol.13 No.1

The purpose of this study was to analyze the changes of trunk's 3-dimensional twist angle(front·rear inclination angle, right·left inclination angle, internal·external rotation angle) and angle of the lower extremity as to pattern when performing Morote-Seoinage(M.S.N.:two arm shoulder throw) in judo who was 5 females university representative judokas of light weight category in judo, and filmed on video cameras(60field/s). The data of this study digitizied by KWON3D 2.1 program computed the average and standard deviation calculated individual 5 trials with Programing Lan view 6i. From the data analysis & discussion, the following conclusions were drawn: 1) The kinds of pattern were 3 types, when performing M.S.N.,1st pattern was pulling, 2nd upper body drown, 3rd lower center of gravity, respectively. 2) A pattern : Right (knee/hip) angle showed flextion and extension in Kuzushi phase and flexed in Tsukuri to Kake phase. Left (knee/hip) angle flexed in whole phase. B pattern : Right (knee/hip) angle showed flextion and extension in Kuzushi phase and flexed in Tsukuri to Kake phase. Left knee angle slowly flexed in Kuzushi to Tsukuri phase and suddenly flexed in Kake phase. Left hip angle showed flextion and extension in Kuzushi phase and flexed in Tsukuri to Kake phase. C pattern : Right (knee/hip) angle showed flextion and extension in Kuzushi phase and flexed in Tsukuri to Kake phase. Left knee angle flexed in whole phase. Left hip angle angle showed flextion and extension in Kuzushi phase and flexed in Tsukuri to Kake phase.

사무직 근로자에서 직무스트레스 및 VDT작업과 목·어깨 근골격계 증상과의 관련성

이의철,김환철,정달영,김동현,임종한,박신구 대한산업의학회 2007 대한직업환경의학회지 Vol.19 No.3