[논문]Operational Characteristics of CO2 Laser Adopted by Superposing-Discharge

Hee-Je Kim,Hyun-Ju Chung,Byoung-Dae Min,Jong-Han Joung,Sung- lun Park 釜山大學校生産技術硏究所 2003 生産技術硏究所論文集 Vol.62 No.-

오늘날 현저한 CO2 레이저의 응용 추세에 발맞추어 보다 다양한 형태의 출력 제어 기술이 대두되고 있다. 본연구에서는multi-Pulse Superposing-Discharge 기술을 이용하여 다양한형태의 CO2 레이저의 펄스를 성형 하였다. 펄스 성형을 위한 방법으로 PIC one-chip microprocessor를 이용하여 삼중 PFN 모률의 SCR을 각각 고유의 지연시간을 가지도록 제어하였다. 실험에 사용된 삼중 PFN 모률의 전원 회로는 각각 캐패시터 인덕터,SCR,고압 펄스 트랜스 그리고 고압 트랜스 2차측에 브릿지 정류기로 구성 하였다. 고압 펼스 트랜스의 1차측을 제어하므로서 PFN 모률의 동작을 저 전압에서 수행 할 수 있다. 트랜스의 2차측에 연결된 전파 정류기는 펄스 에너지를 부하에 지속적으로 전달한다. 본 연구에서는 삼중 PFN 모률의 각각의 SCR을 다른 시간 가격을 두고 트리거 하므로서 다양한 Long pulse shaping을 실현하였다. 또한 약 250-1000μs 의 주기를 가지는 다양한 펄스형 레이저 빔을 얻었다.

Improved Properties of Nanocrystalline Cellulose Isolated from Kraft Pulp by Electron Beam Irradiation

Kim, Sun-Young,Lee, Byoung-Min,Lee, Yeong-Ju,Kim, Du-Yeong,Jeun, Joon-Pyo,Kang, Phil-Hyun American Scientific Publishers 2016 Journal of nanoscience and nanotechnology Vol.16 No.10

<P>In this study, we investigated an improvement to the properties of nanocrystalline cellulose (NCC) from kraft pulp using electron beam irradiation (EBI). The EBI of the kraft pulp was performed at various doses (25, 50, and 75 kGy) and then hydrolyzed with 55% sulfuric acid at 50 degrees C (preheated) for 20 min. The hydrolysate of kraft pulp was characterized using X-ray diffraction (XRD), particle size distribution, thermogravimetric analysis (TGA), and transmission electron microscopy (TEM). The NCC of pristine kraft pulp was obtained with a broad size distribution (0-700 nm), an average particle size of 220 nm, and a 75.5% crystallinity index after 20 min of acid-hydrolysisat 50 degrees C. However, isolated NCC from 75 kGy irradiated kraft pulp was obtained with a narrow size distribution (0-530 nm), an average particle size of 160 nm, and 83.2% crystallinity after 20 min of acidhydrolysisat 50 degrees C. These results indicate that the size and crystallinity of NCC were easily controlled by adjusting the EBI dose.</P>

洛東江 河口周邊의 防災對策에 관한 基礎的인 硏究

민일규,김원규,최병습,박상길,김가현 釜山大學校生産技術硏究所 1996 生産技術硏究所論文集 Vol.51 No.-

波浪과 흐름이 共存하는 大河川 河口部인 洛東江 河口域에서 洛東江 河口둑을 基点으로 波浪, 흐름, 地形變動, 潮流, 洪水位等을 評價基準으로 하여 災害에 대한 基本的인 評價를 實施했다. 波浪, 潮流, 洪水位等이 水位上昇을 透發시켜 周邊地域을 浸水시킬 수 있는 危險性의 與否를 實測과 數値計算을 통하여 實施하였다. 地形變動은 實測만을 통하여 地形變動率을 調査하였다. 資料를 分析한 結果 洛東江 河口地域은 波浪, 흐름과 波浪이 共存하는 領域으로 區分된다. 數値計算結果에 의하면 河口部에서의 來襲波高가 直接 河口둑 水門과 주변構造物에 미치는 影響은 크지 않았다. 또한, 3次元 波高分布를 볼 때 河口 水路를 따라서 거슬러 올라오는 波浪의 影響은 거의 없었다. 洪水位와 流速은 災害를 透發시키는 主要因子로 評價되었다. 波浪에 의한 異常高潮와 漲潮流와 潮汐의 滿潮時間 및 最大洪水量이 時間적으로 一致되는 境遇, 河口둑 周邊地域의 水位 上昇과 流速의 停滯現狀으로 浸水狀態가 發生한다. For the investigation of inundation disasters by wave setup in the Nakdong Estuary of the Large River which waves and currents are coexist, the wave surveying data was analyzed and the numerical model was applied to the Estuary. In this study, the result of surveying data analysis shows that waves have little effect on the surroundings. As the result of numerical computation, waves have seldom direct influence upon the barrage and its gates. Also, according to three dimension distribution of waves, it is found that coming up waves along the Estuary channel and the setup of waves have seldom effect barrage structures.

소아 Henoch-Schonlein 신염의 임상경과와 조직학적 특성 : Renal Outcome and Prognostic Factors

김병목,장창환,조민현,곽정식,고철우,구자훈 대한신장학회 2003 대한신장학회잡지 Vol.22 No.6

동유를 함유하는 목조주택 외장용 옻칠도료의 적용

송병민,이병후,김현중 한국목재공학회 2003 목재공학 Vol.31 No.4

본 연구에서는 식물성 오일인 동유에 국내산 생칠 또는 정체칠을 10, 20, 30 및 40 wt.% 혼합하여 목조주택 의장용 도료를 제조하고 기존의 의장용 도료인 오일스테인과 내후성을 비교하여 외장용 도료로서의 가능성을 세시하려고 하였다. 생칠, 점제칠 및 동유를 혼합하여 제조된 도료의 성질에 대한 실험결과를 보면 생칠이 정제칠에 비해 화학구조 내에 존재하는 -OH group이 많으며 경화특성이 좋은 것으로 나타났다. 동적점도는 정제칠이 생칠에 비해 Frequency 15OC red/s 이하에서는 높은 것으로 나타났지만 150 red/s 이상에서는 거의 비슷한 수준의 동적 점도를 보여 주었다. 또한 동유에 생칠을 혼합할수록 화학구조내의 -OH group이 증가하고 경화온도가 증가함을 보여 주었다. 내후성 실험결과는 제조된 도막의 색차변화가 기존에 목조주택 의장용 도료로 사용하는 오일스테인에 비해 높게 나타났지만 동유에 생칠을 40 wt% 혼합한 경우와 정체칠을 30 wt% 또는 40 wt % 혼합한 경우 거의 비슷한 색차 변화를 보여주었다. 색차를 제외한 광택도 변화. 접촉각 변화의 측정 결과는 오일 스테인의 변화정도와 유사한 결과를 보여 주어 목조주택 외장용 도료로써의 가능성을 보여 주었다. In this study, we investigated the weathering properties of Korean Rbus lacquers containing tung oil and their potential use as exterior coatings. The finished lacquers were prepared with a raw Korean Rbus lacquer or refined Korean Rbus lacquer content of 10, 20, 30 and 40 wt% (corresponding to ratios of 10/90, 20/80, 30/70 and 40/60 by weight of Korean Rbus lacquer/tung oil, respectively) The curing temperature of the prepared lacquer increased with increasing the content of the raw Korean Rbus lacquer. This increased curing temperature is related to higher proportion of hydroxy1 groups in the prepared lacquer, due to the content of the raw Korean Rbus lacquer. In accelerated weathering testing, the changes in the gloss and contact angle of the prepared lacquers showed a similar trend to that of traditional exterior oil stain. In addition, the prepared lacquers containing tung oil showed greater discoloration than traditional exterior oil stain. However, the discoloration of the prepared lacquer with a raw Korean Rbus lacquer content of 40wt%, and that of the prepared lacquer with refined Korean Rbus lacquer contents of 30 wt% and 40 wt%, showed a similar trend to that of traditional exterior oil stain. Consequentially, these prepared lacquers showed a potential for being used as exterior coatings.

동종골 이식을 이용한 경골 근위부 절골술

노정호,민병현 대한슬관절학회 2002 대한슬관절학회지 Vol.14 No.2

목적: 내반슬을 동반한 골관절염의 치료방법 중 개방형 경골 근위부 절골술에서 동종골이식의 유용성을 알아보고자 하였다. 대상 및 방법: 1999년 4월부터 2001년 1월까지 내반슬을 동반한 골관절염 환자중 1년 이상 추시가 가능하였던 총 8명(8례)을 대상으로 개방형 경골 근위부 절골술과 함께 동종골로 골이식한후 L-형태의 금속판으로 내고정을 실시하였다. 수술전후 체중부하 전후면 방사선 사진을 통해 내반슬 교정의 정도를 측정하였고 추시관찰중 내고정물 제거술시 골조직을 채취하여 표본을 image analyzer로 분석하여 골유합의 정도를 파악하였다. Lysholm's knee score와 Hopital for Special Surgery(HSS) knee score를 이용하여 환자이 기능적 상태를 평가하였다. 결과: 측정된 수술전 체중부하 전후면 방사선 사진 상 내반각의 평균값은 5.3±4.3˚이었고 수술후 체중부하 전후면 방사선사진상 교정각의 평균값은 16.1±4.1˚ 이었으며 외반각 평균값은 10.7±4.3˚이었다. 추시 관찰에서 시행한 체중부하 전후면 및 측면 방사선사진상 골유합은 모두 이루어 졌으며 교정 손실각온 평균 1.5±1.0˚이었으며 내고정물 제거시 시행한 골조직표본을 image analyzer(ProPlus® system)로 분석한 결과 검체는 모두 골조직으로 이루어져 있으며 이중 생골과 사골의 비율은 3.3:1로 생골의 비율이 전체의 76.7±8.0%로 나타내었다. 최종 추시시인 수술 15.3개월 후의 Lysholm's knee score와 HSS knee score의 평균 값은 각각 66.2±8.3에서 75.7±9.1로, 55.2±9.0에서 79.0±7.5로 증가하였다. 결론: 동종골을 이식한 개방형 경골 근위부 절골술에서 절골부위는 이식된 동종골에 의하여 골유합이 잘 이루어 졌고 만족할 만한 교정각을 얻을 수 있었으며 교정각 소실이 적었고 향상된 슬관절 기능을 나타내었다. Purpose: The purpose was trying to clarify utility of allogenous bone graft on open type high tibial osteotomy, among the method of treatment of osteoarthritis with genu varum deformity. Materials and Methods: Working with eight patients who have osteoarthritis with genu varum deformity, performed the open type high tibial osteotomy, and after transplanting allogenous bone graft, fixed using L-shaped plate. Before and after the operation, measured the degree of correction of genu varum through radiography of anterior and posterior of weigh load, understudied degree of union by testing bone histology during removal of implant, and evaluated functional factor as well as improvement of patients using Lysholm's knee score and HSS knee score. Results: According to radiography of anterior and posterior of weigh load, the average of varus angle was 5.3±3.2˚ before operation, the average of correction angle was 16.1±4.1˚ after operation and the average of valgus angle was 10.7±4.3˚. By radiography of anterior and posterior of weigh load and lateral taken during the continual observation, complete bone union was seen. It got result that bone histology of transplanted part was composed of osteologic tissue and ration of live bone and dead bone was 3.3:1, which live bone was 76.7±8% by image analyzer(Pro Plus® system) during the implant removal. The average of correction loss angle was 1.5±1.0˚ After 15. months, average period of observation, average of Lysholm's score and HSS knee score were increased from 66.2±8.3 to 75.7±9.1 and from 55.2±9.0 to 79.0±7.5 respectively. Conclusion: The method that using a transplantation of allogenous bone graft on open type high tibial osteotomy, can be a fine surgical technique because it gains a perfect union, has an inconsiderable loss of correction angle and precision of correction angle, and can be contributed to the improvement of functional knee joint.

신생아에서 용질배설에 관한 연구

김경범,박재현,최병민,이현희,윤재균 관동대학교 의과학연구소 2000 關東醫大學術誌 Vol.4 No.1

Purpose : Determination of urinary concentration in neonate is mandatory for precise management of fluid and electrolyte requirements. Although measurement of urine specific gravity has been proposed far monitoring fluid requirements, the reliability of specific gravity does not accurately predict urine osmolalities in the neonate period. So specific gravity should be checked by measuring the osmolality. Also the urinary excretion of creatinine has been used for the assessment of hydration state. We present the result of specific gravity, urine osmolality, urine creatinine in a spot urine sample during the first week of life as a reliable reference standard. Methods : Spontaneously-voided urine sample were obtained in 40 full term neonates. Two urine samples were available with a interval of 4 to 7days (A: 1st day, B: 4 - 7days), Urine sample was tested for specific gravity with a strip test. Also urinary osmolality, urinary creatinine, urinary creatinine/osmolality ratio were measured. Results : The mean of specific gravity tested by the strip test was 1.006±0.0040 (A) , 1.005±0.0036 (B). The mean of urine osmolality and creatinine were 177.7 ± 103.0 and 30.9±21.6 (A), 145.7 ±90.3 and 26.4± 17.7 (B). The mean of excretion rate of urine creatinine/osmolality ratio was 18.2 ±8.5 (A), 19.4 ±9.1 (B). There was correlation between urine specific gravity and osmolality in neonate(r=0.833(A), 0.842(B) p<0.001). Urinary creatinine/osmolality levels of the first urine samples were closely correlated with the second samples (r=0.617, p<0.001). Conclusion : Specific gravity of urine was enough to predict the osmolality in neonate. But Specific gravity should be checked by measuring the osmolality of urine. Urine osmolality and creatinine were spread over a wider range and did not used to urinary excretion of solute in neonate. Urinary creatinine/osmolality ratio can be used to standadise the urinary excretion on solute in the first week of life.

진행성 주상월상골 붕괴에서 주상골 제거후 수근골간 유합

강신영,민병현,전창훈,한경진 아주대학교 의과학연구소 1998 아주의학 Vol.3 No.1

Scapholunate advanced collapse (SLAG) deformity most often occurs with chronic rotary scaphoid instability resulting from scapholunate ligament tear and scaphoid fracture. Prior to 1984 when Dr. Kirk Watson reported his concept on SLAG wrist deformity, the most popular procedure for this pathological condition was scaphoid implant arthroplasty with or without midcarpal fusion. We have reviewed 15 cases of SLAG deformity during 1984 to 1993, which were treated with scaphoid excision and midcarpal fusion. Among them, scaphoid implants made of silicone were inserted in 4 cases. Scaphoid implant arthroplasty without carpal fusion was excluded. The mean period of follow-up was 8.8 years and the mean age of patients was 47.5 years. Males and right wrists were predominant. Wrist motion was limited to 55.6% of the opposite normal wrist and grip power was average 71% of the opposite normal hand. Overall, 8 patients had no pain and 7 patients had mild pain. The grade of pain was minimal. (Rating system: no pain-0, mild-1, moderate-2, severe-3). However, all of the 4 cases of limited carpal fusion with a scaphoid implant developed silicone paniculate induced synovitis and pain. The procedure appears to be effective in maintaining function of the hand with minimal pain up to 5.8 years. However, silicone scaphoid implant appears to be not necessary and is not recommended for this pathological condition with a limited carpal fusion.

족관절 내과골절에서 피질골 나사못을 이용한 변형된 긴장대 고정술

최호림,도현우,김병흠,김규현,박종석,송준민 대한골절학회 2004 대한골절학회지 Vol.17 No.4

목적 : 전위된 족관절 내과골절에 대해 피질골 나사못을 이용한 변형된 긴장대 고정술을 이용한 치료결과를 분석해 보고자 하였다. 대상 및 방법 : 2001년 1월부터 2003년 1월까지 전위된 내과골절에 대해 변형된 긴장대 고정술을 시행 받고 최소 1년 이상 추시관찰 가능 하였던 24례를 대상으로 하였다. 남자 13례, 여자 11례로 평균 연령은 46세였다. 골절은 Lauge-Hansen 분류법을 사용하였으며, 결과는 Meyer와 Kumler의 평가 방법을 이용하였다. 결과 : 13례 (54%)에서 우수의 결과를 얻었고, 9례 (38%)에서 양호의 결과를 얻었으며, 운동범위의 제한이 발생한 1례에서 보통, 후외상성 관절염이 발생한 1례에서 불량의 결과를 얻었다. 결론 : 전위된 족관절 내과골절에서 피질골 나사못을 이용한 변형된 긴장대 고정술은 견고한 내고정과 조기 관절 운동이 가능한 효과적인 수술 방법이 될 수 있을 것으로 사료된다. Purpose : To evaluate the clinical results of modified tension band wire technique using cortical screw for treatment of displaced medial malleolar fractures of the ankle. Materials and Methods : From January 2001 to January 2003, 24 patients were treated by modified tension band wiring using cortical screw for medial malleolar fracture. The follow-up period was 12~35 months (average 18 months). There were 13 males and 11 females, and the mean age was 46 years. Fractures were classified by Lauge-Hansen's classification. The results were analyzed by Meyer and Kumler's criteria. Results : There were 13 cases (54%) of excellent, 9 cases (38%) of good, and one case of fair because of limitation of motion of the ankle joint and one case of poor which showed post-traumatic arthritis of the ankle. Conclusion : Modified tension band wire technique using cortical screw can be an effective operative method for the treatment of displaced medial malleolar fractures of the ankle.

급성 골수성 백혈병 환자에서 관해 유도 항암 화학요법 후 발생한 베르니케 뇌증

황진원,정재현,서광원,최병진,송영진,김종윤,이은지,임홍규,이상민 인제대학교 2009 仁濟醫學 Vol.30 No.-

Wernicke's encephalopathy is characterized by the triad of ocular symptoms, ataxia, and mental confusion and neuropsychiatric condition generally caused by acute thiamine deficiency. Although it is common in the severe alcoholics, several other causes also have been identified, such as total parenteral nutrition (TPN) use, hyperemesis gravidarum, anorexia nervosa, hemodialysis, uremia, and acquired immunodeficiency syndrome(AIDS). Chemotherapy in patient with malignanacy and long term total parenteral nutrition following bone marrow transplantation are related with Wernicke's encephalopathy. A 48-year-old woman had been treated with Daunorubicin and Cytarabine for remission induction chemotherapy of acute myeloblastic leukemia and intravenous hyperalimentation due to persistent hematochezia and ileus caused by infiltration of leukemic cell in terminal ileum. She suddenly complained of diplopia, tremor, and mental confusion at 32th day after chemotherapy and generalized tonic-clonic seizure at 34th day after chemotherapy. The diagnosis of Wernicke's encephalopathy was made with clinical presentations and brain MRI. Brain MR T2-weighted & Flair image revealed a high signal intensity lesions bilaterally at the medial thalamus and peri-acueductal grey matter of the midbrain. The patient was successfully treated with vitamin B1. We presented a case of acute Wernicke's encephalopathy developed after remission induction chemotherapy followed by intravenous hyperalirnentation in a patient with acute myeloblastic leukemia.