삼상태 추론과 룰 검증이 가능한 전문가 시스템에 관한 연구

손동욱(Son Dong-Wook),박영문(Park Young-Moon),윤지호(Yoon Ji-Ho) 대한전기학회 1991 대한전기학회 학술대회 논문집 Vol.1991 No.7

오스테나이트계 316L 스테인리스강의 강도 및 감쇠능에 미치는 미세조직의 영향

손동욱(DONG-WOOK SON),이종문(JONG-MOON LEE),김효종(HYO-JONG KIM),남기우(KI-WOO NAM),박규섭(KYU-SEOP PARK),강창룡(CHANG-YONG KANG) 한국해양공학회 2006 韓國海洋工學會誌 Vol.20 No.1

The effects of microstructure on the damping capacity and tensile properties of 316L stainless steel were investigated. Increasing the degree of cold working, the volume fraction of ε-martensite decreased after rising to maximum value at specific level of cold working, the volume fraction of α'-martensite slowly increased and then dramatically increased from the point of decreasing ε-martensite volume fraction. Increasing the degree of cold working, the behavior of damping capacity is similar to that of the ε-martensite. After the damping capacity showing the maximum value at about 20% of cold rolling, damping capacity was decreased with the volume fraction of ε-martensite. Tensile strength was proportional to the volume fraction of α'-martensite, and elongation steeply decreased in the range low volume fraction of α'-martensite, then slowly decreased in range the above 10% volume fraction of α'-martensite. The damping capacity and elongation is strongly controlled by the volume fraction of ε martensite with liner relationship. However, the effect of the volume fraction of α'-martensite and austenite phase on the damping capacity was not observed. Tensile strength was governed by the volume fraction of α'-martensite.

소뇌교각부 비청신경초종종양 환자의 임상특성과 예후분석

손동욱 ( Dong Wook Son ),최창화 ( Chang Hwa Choi ),차승헌 ( Seung Heon Cha ) 대한뇌종양학회 2002 대한뇌종양학회지 Vol.1 No.2

Non-acoustic tumours of the cerebellopontine angle differ from vestibular schwannomas in their prevalence, clinical features, operative management, and surgical outcome. The author analysed various clinical characteristics and surgical result of 24 non-acoustic tumor of cerebellopontine angle to determine their distinctive diagnostic features, the surgical difficulties and outcomes and follow-up results. Methods:A retrospective analysis of clinical notes identified 24 patients with non-acoustic tumours of the cereelopontine angle. Data were extracted regarding presenting clinical features, histopathotogical data after surgical resection, surgical morbidity and mortatity, and clinical outcome(mean 36 months follow up). Results:The study group comprised 12 meningiomas(50%), 7 epidermoid cysts(29%), 3 trigeminal schwannom, 1 primitive neuroectodermal tumor, and 1 meastatic tumor. In patients with meningiomas, symptoms differed considerably from patients presenting with vestibular schwannomas. Cerebellar signs were present in 30% and hearing loss in only 25%. After surgical resection, normal facial nerve function was preserved in 80% of cases. For the meningioma patients, the success rate of of operation(good result) was 90%, any cranial nerve deficit was combined in 10% of patient, and the mortality was 0%. In the epidermoid group, fifth, seventh, and eighth nerve deficits were present in 100%, 14%, and 14% respectively. There were no new postoperative facial palsies. There was one perioperative death from pneumonia and meningitis and the rest(85%) showed good oucome in epidermoid patient. Overall, there were no recurrences requiring reoperation. Conclusion:Patients with non-acoustic lesions of the cerebellopontine angle often present with different symptoms and signs from those found in patients with schwannomas. Hearing loss is less prevalent. Cerebellar signs and facial paresis are more common as presenting features. Non-acoustic tumours of cerebellopontine angle can usually be resected with facial nerve preservation.

원위 대퇴골 골절에서 슬관절 강직의 위험 인자

손동욱 ( Dong-wook Son ),김형수 ( Hyoung-soo Kim ),최우영 ( Woo-young Choi ) 대한골절학회 2018 대한골절학회지 Vol.31 No.4

목적: 원위 대퇴골 골절을 근육 아래 잠김 금속판을 이용하여 치료한 환자에서 발생하는 슬관절 강직의 위험 인자에 대해 조사하고 임상적 방사선적 결과에 대해 분석하고자 한다. 대상 및 방법: 본 연구는 후향적 환자 대조군 연구로 슬관절 강직의 환자군은 수술 후 12개월의 관절 운동 범위가 90도 이하 혹은 마취하 관절 수동술을 시행 받은 환자이고 대조군은 정상 관절 운동 환자였다. 발생 가능한 위험인자의 빈도를 단변량 및 로지스틱 회귀 분석을 이용하여 분석하였다. 결과: 환자군 14예, 대조군 40예로 54예의 환자가 연구에 포함되었다. 단변량 분석상 분쇄골절, 관절내 골절, 개방성 골절, 일시적 외고정 장치, 심한 퇴행성 관절염 및 장기간의 부목 고정이 슬관절 강직의 위험 인자였다. 하지만, 다중 회귀 분석상에서는 신전기전의 손상이 유일한 위험 인자였다 (p=0.001; odds ratio, 42.0; 95% confidence interval, 5.0- 350.7). 결론: 원위 대퇴골 골절에서 슬관절 강직을 발생시킬 수 있는 위험 인자들을 정확히 알고 있다면 슬관절 강직 예방에 도움이 될 것으로 생각된다. 특히 슬개골 골절이나 대퇴 사두근의 개방성 손상과 같은 신전 기전의 손상은 슬관절 강직을 독립 적으로 예측할 수 있는 주요 위험 인자이다. Purpose: The aims of this study were to evaluate risk factors for knee stiffness after the fixation of distal femoral fractures, and to analyze the clinical and radiologic outcomes. Materials and Methods: This is a retrospective case control study of 104 consecutive patients who have a distal femoral fracture and were treated with a submuscular locking plate. The case group comprised of patients with 12-month postoperative range of motion (ROM) ≤90° or a history of manipulation under anesthesia. The case group was compared with the control group of patients with a 12-month postoperative ROM >90°. The possible risk factors were evaluated by univariate and logistic regression analysis. The postoperative ROM and Knee Society clinical rating system was evaluated for the clinical assessment and the distal femoral angle on a whole-extremity scanogram was measured for radiologic assessments. Results: Fifty-four patients were included in the study (14 in the case group, 40 in the control group). Univariate analysis showed that comminuted fracture, intra-articular fracture, open fracture, temporary external fixation, severe osteoarthritis, and prolonged immobilization placed patients at an increased risk for knee stiffness. On the other hand, multivariate logistic regression showed that an extensor mechanism injury was the only significant predictor (p=0.001; odds ratio, 42.0; 95% confidence interval, 5.0-350.7). The ROM and Knee Society score were significantly lower in the case group; however, the coronal alignment was similar in the case and control group. Conclusion: Various factors that delay postoperative knee motion place patients at increased risk of knee stiffness. Understanding these risk factors may help surgeons prevent postoperative knee stiffness after distal femoral fractures. In particular, extensor mechanism injury, such as patella fracture or open quadriceps injury, was found to be an independent predictable factor associated with knee stiffness.

전통 생약재에서의 항노화와 주름 개선 활성 신소재 탐색

이상은 ( Sang Eun Lee ),손동욱 ( Dong Wook Son ),윤여필 ( Year Pill Yoon ),임태형 ( Tae Young Lim ),조자운 ( Ja Wun Cho ),김현수 ( Haen Su Kim ) 대한화장품학회 2005 대한화장품학회지 Vol.31 No.2

본 연구는 화장품 소재개발에 있어 보다 안전하고 우수한 활성을 나타내는 천연 소재를 개발하고자 하였다 본초학과 식품공전에 수재되어 있는 전통생약재에 대한 연구는 국내 화장품 원료개발의 중요한 부분으로써 우리나라가 경쟁력을 가질 수 있는 부분으로 사료되며, 본 연구에서는 폐와 피부 질환에 사용되는 전통생약재 121종을 선별하였다. 이들 전통생약재 추출물들을 대상으로 DPPH free radical 소거법과 SOD 활성 측정법에 의한 항산화 활성과 주름 생성의 주 기전에 관련된 elastase 효소 억제 활성을 관찰하였다. 항산화 활성을 보이면서도 주름 형성관련 효소인 엘라스타제에 대한 억제 활성을 지니는 전통생약재 9종을 선별하였다. 항주름/피부탄력 활성을 나타내리라 사료되는 9종의 생약재에 대한 각각의 정상 세포에 대한 세포독성을 측정한 결과, 효과를 나타내리라 여겨지는 0.1 g/mL 이하의 농도에서 세포 독성이 없는 것으로 확인되었다. 또한 인체피부 일차 자극 실험을 통해 피부자극 유무를 측정한 결과 피부자극이 없음을 확인하였다 본 연구를 통해 식품공전과 동의보감 자료에 의거, 폐와 피부질환에 관련된 전통생약재 121종 중 9종에 대해 항주름과 피부탄력에 관련한 향장 소재로써의 개발 가능성을 확인하였다. As a part of searching tot the natural components which inhibit the skin aging and wrinkle formation, the 80% methanolie extracts of 121 species of traditional herbal medicines used to treat lung and skin disease were investigated for their in vitro anti-oxidative activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) and superoxide radicals, and inhibitory activity against elastase. We selected 9 kinds of the traditional herbal medicines showing inhibitory activities of winkle formation. The effective concentrations of 9 candidates for anti-wrinke/skin firming activity was less than 0.1 mg/mL, and there is no toxicity to cell viability at these concentrations. Through analysis of human skin primary patch test data, the traditional herbal medicines represented non-irritant materials. We suggest that these 9 candidates with ability to help anti-wrinkle/skin firming may be useful for functional cosmetic materials.

점적관개 시 토성별 습윤ㆍ건조 특성 비교

김학진(Hak-Jin Kim),손동욱(Dong-Wook Son),허승오(Seung-Oh Hur),노미영(Mi-Young Roh),정기열(Ki-Yuol Jung),박종민(Jong-Min Park),이중용(Joong-Yong Rhee),이동훈(Dong-Hoon Lee) (사)한국생물환경조절학회 2009 시설원예‧식물공장 Vol.18 No.4

본 연구에서는 정밀관수를 위한 관수시간, 점적라인 설치 등 관수시스템 설계를 위한 기초 데이터를 얻고자 점적관수 시 토성에 따른 물의 수분함량변화를 공간적, 시간적 변이의 차이를 구명하였다. 20㎝의 간격의 노즐로 설치된 1열 점적관을 이용 관수 하였을 경우 양토와 사양토내의 수분은 중심을 따라 대칭 형태를 유지하면서 이동하였으나 수분확산 폭은 양토가 더 넓고 속도가 느린 경향을 나타내었다. 상대적으로 높은 모래성분 함량을 갖는 양질사토의 경우는 낮은 수분 보유력으로 인하여 위치별 수분함량의 변화는 상대적으로 낮았으며 그만큼 물 빠짐정도가 큰 것으로 나타났다. 관수개시점과 종말점을 고려하였을 때 사양토의 경우 20㎝ 깊이에서 관수개시 30분 후에 수분의 포화가 이루어졌으나 양토와 양질사토의 경우는 약 80분이 소요되어 효율적인 수분공급 측면에서 관수시간은 토성별로 달리해야 하는 것으로 나타났다. 깊이 10㎝에서의 시간에 다른 토양수분의 감쇠특성은 지수함수의 형태를 나타내었으며 토양별 안정된 상태에서의 수분함량은 양토, 사양토, 양질사토 각각 17.6%, 6.2%, 4.2%로 예측되어 토성에 따라 잔여수분함량은 차이가 있음을 확인하였다. 토양수분함량과 토양수분퍼텐셜과의 관계를 나타내는 수분특성곡선은 시험 토양의 경우 모두 높은 결정계수를 갖는 지수함수로 근사가 가능하여 수분퍼텐셜을 이용하여 측정하는 재배시스템에서 대응하는 수분함량 예측에 유용한 관계식을 얻었다. Maintenance of adequate soil water content during the period of crop growth is necessary to support optimum plant growth and yields. A better understanding of soil water movement for precision irrigation would allow efficient supply of water to crops, thereby resulting in minimization of water drainage and contamination of ground water. This research reports on the characterization of spatial and temporal variations in water contents through three different textured soils, such as loam, sandy loam, and loamy sand, when water is applied on the soil surface using an one-line drip irrigation system and the soils are dried after the irrigation stops, respectively. Water contents through each soil profile were continuously monitored using three Sentek probes, each consisting of three capacitance sensors at 10, 20, and 30㎝ depths. Spatial variability in water content for each soil type was strongly influenced by soil textural class. There were big differences in wetting pattern and the rate of downward movement between loam and sandy loam soils, showing that the loam soil had a wider wetting pattern and a slower rate of downward movement than did the sandy loam soil. The wetting pattern in loamy sand soil was not apparent due to a low variability in water content (<10%) by a lower-water holding capacity as compared to those measured in the loam and sandy loam soils, implying that the rate of water drainage below a depth of 30㎝ was high. When soils were dried, there were highly exponential relationships between water content and time elapsed after irrigation stops (r²≥ 0.98). It was estimated that equilibrium moisture contents for loam, sandy loam, and loamy sand soils would be 17.6%, 6.2%, and 4.2%, respectively.

이온성 고분자 액추에이터 용 그래핀 나노복합체 전극

이봉기(Bong-Kee Lee),손동욱(Dong Wook Son),박상규(Sang-kyu Park),김창완(Chang Wan Kim) 대한기계학회 2012 대한기계학회 춘추학술대회 Vol.2012 No.6

논문 : 생물생산시설 및 환경공학 ; 코발트전극과 자동시험장치를 이용한 파프리카 양액 내 무기인산 측정

김학진 ( Hak Jin Kim ),손동욱 ( Dong Wook Son ),권순구 ( Soon Goo Kwon ),노미영 ( Mi Young Roh ),강창익 ( Chang Ik Kang ),정호섭 ( Ho Seop Jung ) 한국농업기계학회 2011 바이오시스템공학 Vol.36 No.5

The need for rapid on-site monitoring of hydroponic macronutrients has led to the use of ion-selective electrodes, because of their advantages over spectrophotometric methods, including simple methodology, direct measurement of analyte, sensitivity over a wide concentration range, and low cost. Stability and repeatability of response can be a concern when using multiple ion-selective electrodes to measure concentrations in a series of samples because accuracy might be limited by drifts in electrode potential. A computer-based measurement system could improve accuracy and precision because of both consistent control of sample preparation and easy calibration of sensors. Our goal was to investigate the applicability of a cobalt-based electrode used in conjunction with a laboratory-made automated test stand for quantitative determination of PO4-in hydroponic solution. Six hydroponic solutions were prepared by diluting highly concentrated paprika hydroponic solution to provide a concentration range of 1 to 300 ppm PO4-P. A calibration curve relating electrode response to phosphate in paprika hydroponic solution titrated to pH 4 with 0.025M KHP was developed based on the Nikolskii-Eisenman equation with a coefficient of determination (R2) of 0.94. The laboratory-made test stand consisting of three cobalt-based electrodes measured phosphate concentrations similar to those obtained with standard laboratory methods (a regression slope of 0.98 with R2=0.80). However, the y intercept was relatively high, 30 ppm, probably due to the relatively large amount of variation present among multiple measurements of the same sample. Further studies on the high variation in EMFs obtained with cobalt electrodes during replicate measurements were required for P estimations comparable to those obtained with standard laboratory instruments.

지속성 외래 복막 투석 환자에서 심한 기침으로 인해 발생한 복직근 혈종 1예

정영국 ( Young Kuk Chung ),손동욱 ( Dong Wook Son ),이승우 ( Seoung Woo Lee ),엄욱현 ( Wook Hyun Um ),김덕영 ( Deok Young Kim ),송준호 ( Joon Ho Song ),김문재 ( Moon Jae Kim ) 대한신장학회 2007 Kidney Research and Clinical Practice Vol.26 No.6

0.5C-17Cr-0.5Ni 마르텐사이트계 스텐인리스강의 인장성질에 미치는 탄화물의 영향

권순두(Soon-Doo Kwon),손동욱(Dong-Wook Son),강창룡(Chang-Yong Kang) 한국동력기계공학회 2016 동력시스템공학회지 Vol.20 No.3