임펄스 잡음 환경하에서의 최우 검출기 ( An MLSD in Impulsive Noise Environment )

박철희,조용수 한국통신학회 1996 한국통신학회 학술대회논문집 Vol.15 No.1

중・고 체조선수의 힘 물구나무서기 운동학적 분석 -성공여부를 중심으로-

박철희 한국체육교육학회 2019 한국체육교육학회지 Vol.24 No.3

본 연구는 기계체조 마루운동 종목에서 힘 물구나무서기 동작을 수행했을 때 성공 동작과 실패 동작에 따라운동학적 차이를 비교 분석하였다. 마루운동에서 입상실적이 있는 G체육중·고등학교 기계체조 선수 4명(나이: 18.0±1.4세, 신장: 157.5±10.5cm, 체중: 47.8±11.8kg중, 경력: 6.3±1.0년)을 연구대상으로 선정하였고, 5대의 실내용 적외선 카메라를 이용하여 촬영하였다. 원하는 동작 자료획득과 분석을 위해 19mm 반사 마커 23개를 해부학적 주요지점에 부착시켰고, 15개 분절 신체모델을 사용하여 운동학적 변인 계산을 실시하였다. 분석결과 첫째, 전체 소요시간은 성공 동작이 실패 동작보다 짧았다. 구간별 비율은 P1 구간과 P3 구간에서 성공동작이 높았으며, P2 구간에서 성공 동작이 낮았다. 둘째, 신체중심 수평변위와 수직변위는 차이점이 없었다. 셋째, 신체중심 속도는 P2 구간에서 성공 동작이 실패 동작보다 느린 속도로 진입하였다. 넷째, 어깨관절 각도는 E2, E3, E4에서 성공 동작이 실패 동작보다 컸다. 다섯째, 엉덩관절 각도는 E2에서 성공 동작이 실패 동작보다 작았으며, E4에서는 성공 동작이 실패 동작보다 컸다. 종합하면 힘 물구나무서기 동작의 완성도를 높이기위해 짧은 소요시간과 시간 비율도 중요하지만, 어깨관절과 엉덩관절의 각도유지가 매우 중요함을 알 수 있었다. 따라서 꾸준한 근력운동과 유연성 운동을 통해 어깨관절의 신전과 엉덩관절의 굴곡을 강조하면서 올바른자세를 숙달시키는 반복 훈련이 필요하다. 또한, 본 연구에서는 운동학적 분석에 국한되었다. 이러한 한계점을보완하기 위해 후속연구에서는 지면 반력 분석과 근전도 분석을 통해 더욱 과학적이고 객관적인 근거를 제시할 수 있는 연구가 필요하다고 판단된다. Purpose: The purpose of this study was to compare kinematic differences between successful (ST) and failed trials (FT) of press-handstand in gymnastics. Method: Four subjects, consisting of middle and high school gymnasts, participated in this study and have medal records of national competitions. Five motion capturing cameras and 23 reflective markers were used for motion data collection. Kinematic variables were calculated by 15-segment rigid-body model. Results: Total motion time of ST was shorter than that of FT. The relative phase times of P1 and P3 were longer, but that of P2 was shorter in ST. There were no difference in horizontal and vertical displacements between two conditions. The shoulder joint angle of ST was larger than that of FT in E2, E3, and E4. The hip joint angle of ST was smaller than that of FT in E2 and larger in E4. Conclusion: The shorter motion time and longer time ratio were important for obtaining ST in press-handstand, but maintaining shoulder and hip angles in major events is more important for ST. It is necessary to master press-handstand skill with correct posture repeatedly while emphasizing flexion of shoulder and hip joint through continuous strength and flexibility training. This study was limited to kinematic analysis. Further research on ground reaction force and electromyography are recommended to reinforce scientific foundations of press-handstand motion.

LRH 유도체의 투여와 방사선조사가 백서의 골밀도에 미치는 영향

박철희,이규섭,황인섭,조혜원,윤만수,채호진,김원희 대한폐경학회 1997 대한폐경학회지 Vol.3 No.1

To study the changes of bone density after administration of gonadotropin releasing hormone agonists(GnRHa) as well as X-ray irradiation, the author has performed animal experiments using rats of 250 to 300 grams. Dual photon absorptiometry was used to scan several segments, head, humerus, lumbar vertebrae, femur, tibia, tail and total body. For the GnRHa group, bones were checked four times: before treatment, 4 weeks after decapeptyl injection, 8 weeks and 12 weeks after. And for those rats that received irradiation were checked three times: before and 4 and 8 weeks after. The latter consist of two subgroups, 4,000 rads and 10,000 rads. The results obtained were as follows: 1. Bone mineral density after decapeptyl injections were significantly decreased in lumbar vertebrae at 12 weeks and in total body scan at 8 and 12 weeks. 2. The percentages of bone loss after 4, 8 and 12 weeks of decapeptyl use were 0.4, 2.5 and 3.2 percent, respectively. 3. The percentages of loss in trabecular bones after 4, 8 and 12 weeks of decapeptyl use checked by histomorphometry were 7.7, 23.9 and 26.5% in humerus and 10.0, 32.1 and 38.8%, respectively in femur. Those in cortical bones after 4, 8 and 12 weeks were 5.4, 17.5 and 20.4% in humerus and 8.6, 15.7 and 19.1% respectively in femur. 4. In those received 4,000 rads of X-ray irradiation, bone mineral density was significantly decreased in both head and total body at 8 weeks while in those of 10,000 rads it was significantly decreased in lumbar vertebra, tibia as well as total body scans at 8 weeks. 5. The percentages of bone loss after 4 and 8 weeks of irradiation were 1.7 and 4.4 percent in 4,000 rads group and 3.3 and 7.7 percent in 10,000 rads group. 6. The bone loss from irradiation was dose-dependent and seem to be progressive till 8 weeks after irradiation. 7. Cortical bones also were damaged from earlier stage those the degree of bone loss was severe in trabecular bones, the degree of which are much severe by irradiation than LRH analogue. From above results, it can be concluded that GnRHa decreases bone mass and density in rats especially in lumbar vertebrae and in total body, and X-ray irradiation do decreases bone density in rats through not only loss of estrogen induced by castration but also direct damage of bones.

지하수 변동특성을 고려한 국가지하수 관리측정망 확대 방안

박철희,이소라,손영철,김지욱,김규범 대한지질공학회 2022 대한지질공학회 학술발표회논문집 Vol.2022 No.1

고이즈미정권의 대외정책 결정 논리와 한국의 외교 대응 전략

박철희 국립외교원 외교안보연구소 2003 (KINU) 정책연구시리즈 Vol.2002 No.11

담관내 금속스텐트 삽입 후 추적검사로 자기공명담도조영술의 이용가능성

박철희,양달모,김학수,조성휘,김형식,진욱,황희영 대한영상의학회 2002 대한영상의학회지 Vol.47 No.3

목적: 담관내 금속스텐트를 설치한 경우 추적검사로 자기공명담도조영술(MR cholangiography)의 이용가능성을 알아보고자 하였다. 대상과 방법: 1999년 3월부터 2000년 6월까지 담관폐쇄로 담관내 금속스텐드를 삽입한 환자 중 추적검사로 자기공명담도조영술을 시행했던 15명의 환자를 대상으로 하였다. 담관폐쇄의 원인은 간문부담관암(n=6), 총담관암(n=5), 담낭암(n=1), 췌장암(n=3) 이었고, 삽입한 자가팽창형 금속스텐트의 종류는 나이티놀스텐트(n=2), Endocoil 나이티놀스텐트(n=3), Ultraflex Diamond스텐트(n=5) 및 Wallstent(n=5) 였다. 자기공명담도조영술에서 금속스텐트가 위치한 부위의 담관내 고신호강도의 직경을 측정하여 원래 직경의 1/3 미만시 1점, 1/3-2/3 일 경우 2점, 2/3 이상시 3점으로 하였고, 점수가 높을수록 인공물이 적은 것으로 하였다. 결과: Endocoil 나이티놀스텐트는 1.7-3점(평균, 2.3점), 나이티놀스텐트는 1.7-2.3점(평균, 2점), 그리고 Ultraflex Diamond스텐트는 1-3점(평균, 1.7점)의 결과를 보여 대부분 원래 직경의 2/3 정도만 관찰할 수 있었다. Wallstent는 1-1.7점(평균, 1.3점)으로 금속스텐트가 위치한 부위에서는 담관내부가 거의 보이지 않았다. 결론: 담도내 Wallstent와 나이티놀재질의 금속스텐트를 설치한 경우 추적검사로 자기공명담도조영술은 유용하지 않다고 생각한다. Purpose: To evaluate the efficacy of MR cholangiography for follow-up examination after metallic stent placement in the bile duct. Materials and Methods: Between December 1999 and June 2000, 15 patients with biliary obstruction in whom metallic biliary stents had been placed underwent MR cholangiography during follow-up examination. The causes of obstruction were hilar cholangiocarcinoma (n=6), common bile duct cancer (n=5), gall bladder cancer (n=1) and pancreatic cancer (n=3). The types of self-expandable metallic stent employed were the nitinol stent (n=2), the Endocoil nitinol stent (n=3), the Ultraflexed Diamond stent (n=5), and the Wallstent (n=5). Using MR cholangiography, we measured the diameter of that part of the biliary stent which showed high signal intensity, assigning one point if this was less than one third of the stent diameter, two points if between one third and two thirds, and three points if more than two thirds. We decided that a higher score indicated fewer artifacts. Results: The score was 1.7-3 (mean, 2.3) points for the Endocoil nitinol stent, 1.7-2.3 (mean, 2) for the nitinot stent, and 1-3 (mean, 1.7) for the Ultraflex Diamond stant. In most cases, two thirds of the stent diameter was observed. For the Wallstent, the score was 1-1.7 (mean, 1.3) points and the inner portion of the stent was almost invisible. Conclusion: MR cholangiography is not useful for follow-up examination after the placement of Wallstents and three other types of nitinol stent in the bile duct.

Arterial Bleeding of a Thyroid Mass After Thyroid Fine-Needle Aspiration Biopsy: A Case Report

박철희,변성수,김정호,황희영,김하나,정동진,김형식 대한영상의학회 2009 대한영상의학회지 Vol.60 No.6

Thyroid fine needle aspiration biopsy is a very common procedure that is used to assess thyroid nodules; any complications from this procedure are rather rare. We report here on an unusual case of active bleeding with the formation of a large hematoma from a branch of the superior thyroidal artery, and this was caused by a thyroid fine needle aspiration biopsy. To the best of our knowledge, this is the first report of active arterial bleeding after thyroid fine needle aspiration biopsy. The active bleeding was successfully treated by interventional embolization.

한국 현대문학의 방향과 과제-외국 문학과의 관련 양상

박철희,Park, Cheol-Hui 한국대학교육협의회 1984 大學敎育 Vol.12 No.-

돌파구 찾아야 할 한국의 섬유산업

朴哲喜 세계평화교수협의회 1986 廣場 Vol.152 No.-

時調의 傳統과 그 繼承價値

朴喆熙 동국대학교 일본학연구소 1989 일본학 Vol.9 No.-