칸디다뇨증 환자에 있어서 칸디다혈증 동반과 관련된 위험인자 분석

김창오(Chang Oh Kim),김명환(Myoung Hwan Kim),심대근(Dae Keun Shim),조정호(Jung Ho Cho),김병극(Byoung Keuk Kim),김창년(Chang Nyun Kim),송영구(Young Goo Song),김준명(June Myung Kim) 대한내과학회 2001 대한내과학회지 Vol.60 No.5

N/A Background : The early diagnosis of candidemia is critical for the management. The candidemia is known to be associated with 10% of candiduria. But the risk factors in patients with candiduria who are associated with candidemia are not known. We analyzed the risk factors in patients with candiduria who are associated with candidemia. Methods : We retrospectively reviewed 164 patients with candiduria in Yonsei Medical Center from January 1998 to December 1998. Candiduria patients were divided into two groups. Candiduria patients without candidemia (Group 1 , 147 patients) and candiduria patients with candidemia (Group 2 , 17 patients). Results : 1) The mean age of the patients were 57.5 years in group 1 and 62.5 years in group 2. There were no significant differences in the sex ratio between the two groups. 2) Central venous catheter insertion (53%, 100% in group 1 , 2 ), hypotension (14%, 59% in group 1, 2), other associated infections (64%, 100% in group 1, 2), intensive care (41, 76% in group 1, 2) and fever (46%, 82% in group 1, 2) were the very significant risk factors in patients with candiduria who were associated with candidemia. 3) Urinary tract procedure (11%, 88% in group 1, 2), urinary catheter insertion (63%, 94% in group 1, 2), thrombocytopenia (17%, 41% in group 1, 2) and DM (8%, 24% in group 1, 2) were the significant risk factors of candidemia. 4) Candida colony count (cfu/mL) of urine culture was not a significant risk factor 5 ) Mortality rate (27%, 59% in group 1, 2) was significantly high in patients with candidemia. Conclusion : Central venous catheter insertion , hypotension , other associated infections , intensive care and fever were the very significant risk factors of candidemia in patients with candiduria. (Korean J Med 60:479-484 , 2001)

PSInSAR 기법을 이용한 목포지역의 지반침하 관측

김창오(Kim Chang-Oh),김상완(Kim Sang-Wan),박혁진(Park Hyuck-Jin),우익(Woo Ik),김정우(Kim Jeong Woo) 대한토목학회 2005 대한토목학회 학술대회 Vol.2005 No.10

원격탐사자료와 이어도기지 해양관측자료를 이용한 상호 보정

김창오 ( Chang Oh Kim ),심재설 ( Jae SeoI Shim ),황종선 ( Jong Sun Hwang ),이재학 ( Jae Hak Lee ),김수정 ( Soo Jung Kim ),김정우 ( Jeong Woo Kim ) 大韓遠隔探査學會 2005 大韓遠隔探査學會誌 Vol.21 No.2

이어도 종합해양과학기지 및 주변에서 관측된 해수면고도, 해상풍향 및 풍속 자료와 인공위성으로부터 관측된 자료를 비교하여 상호 신뢰도를 검증하고 보완하였다. 인공위성자료는 Topex/Poseidon 레이더고도계 및 ERS-1/2 고도계 및 산란계 자료를 이용하였고 이어도 기지 건설 당시 기지 부근 선상에서 관측된 자료 및 기지에서 최근 관측된 자료를 비교 분석하였다. 위성자료와 1995년 6월 해상탐사자료를 비교한 결과 대체적으로 잘 일치하며 이는 더 많은 위성 자료를 이용 함으로써 보완 가능하다. 한편 거의 실시간으로 제공되는 이어도 기지의 2004년 12월부터 2005년 2월까지 최근 3개월 간 자료를 분석한 결과 자료의 공백 및 비정상 값을 보이는 경우가 많았고 이들을 위성자료와 비교 한 후 통계적으로 상호 보정하였다. 이어도는 육지와 멀리 떨어져 있어 위성해양관측자료를 검증하기에 매우 적합한 반면 이어도 관측 자료를 검증 및 보완하는 가장 효율적인 방법은 위성자료를 이용하는 것이다. Oceanographic measurements from Ieodo Ocean Research Station and its vicinity were compared for assessment and mutually adjusted with satellite data. From the Topex/Poseidon and ERS-1/2 radar altimeter and scatterometer data, sea surface height, wind speed and direction were extracted and analyzed. Shipborne wind direction data acquired in June 1995 show good coherence with the satellite data, while sea surface height and wind speed show differences, possibly resulting from the distance between the measurement points. This can be improved by analyzing more satellite data or using other available shipborne data. The recent 3 months of Ieodo Station data between December 2004 and February 2005 were also analyzed and compared with the satellite data. The Ieodo Station data were found to have considerable gaps during the period as well as seriously biased particular when the data were averaged with some abnormal data. The Ieodo Station and satellite data were then mutually adjusted on the basis of their statistics. Ieodo Station oceanographic measurements are very efficient for ground-truthing of satellite data because they are stationary and the station is located far from the coast. On the other hand, the satellite measurements are the only data to fill up gaps and adjust biases of the Ieodo Station data.

레이더 간섭기법을 이용한 수치고도모델 해상도 향상에 관한 연구

김창오 ( Chang Oh Kim ),김상완 ( Sang Wan Kim ),이동천 ( Dong Cheon Lee ),이용욱 ( Yong Wook Lee ),김정우 ( Jeong Woo Kim ) 大韓遠隔探査學會 2005 大韓遠隔探査學會誌 Vol.21 No.4

ERS-1/2 및 JERS-1 SAR 영상의 레이더 영상 간섭기법을 이용하여 대전지역의 수치고도모델(DEM)을 제작하였다. 도심지역에서는 GPS 측량으로부터 추출된 지상기준점(GCP)를 이용하여 생성된 DEM의 정밀도를 분석하였고, GCP가 없는 산악지역에서는 1:25,000 수치지도로부터 추출된 DEM과의 상대적 고도차를 이용하여 정확도를 평가하였다. 위성의 궤도오차 및 phase unwrapping에 의한 고도 오차를 최소화하기 위해 DEM 생성에 이용되는 전통적인 InSAR 기법 외에 DInSAR 기법을 추가로 적용하였다. 또한 DInSAR 기법 적용시 사용된 DEM의 해상도에 따른 결과의 정밀도를 분석하기 위해 GTOPO30, SRTM-3, 그리고 1:25,000 수치지도로부터 생성된 DEM을 사용하였다. 하나의 ERS tandem 간섭쌍과, 6개의 JERS-1 간섭쌍 분석 결과, 위상간섭기법 적용 시 평지 지역에서의 정밀도는 DEM 사용 여부 및 시용된 DEM의 해상도에 무관하게 약 5-6 m의 고도오차를 보인다. 반면 산악지역에서는 SRTM-3 및 1:25,000 수치지도 DEM을 이용한 DInSAR 기법이 phase unwrapping에 의한 오차를 줄이는데 매우 효과적이었다. 또한 6 개의 JERS-1 간섭쌍의 중첩을 통해 제작한 DEM의 경우 레이더 영상의 낮은 선호대잡음비 및 대기에 의한 오차를 줄일 수 있었다. 다수의 SAR 간섭쌍과 저해상도 DEM을 이용한 위상간섭기법은 저비용으로 빠른 시간 내에 DEM 해상도를 향상하는데 매우 효과적인 수단으로 사용될 수 있다. Digital Elevation Models (DEMs) were generated by ERS-1/2 and JERS-1 SAR interferometry in Daejon area, Korea. The quality of the DEM`s was evaluated by the Ground Control Points (GCPs) in city area where GCPs were determined by GPS surveys, while in the mountain area with no GCPs, a 1:25,000 digital map was used. In order to minimize errors due to the inaccurate satellite orbit information and the phase unwrapping procedure, a Differential InSAR (DInSAR) was implemented in addition to the traditional InSAR analysis for DEM generation. In addition, DEMs from GTOPO30, SRTM-3, and 1:25,000 digital map were used for assessment the resolution of the DEM generated from DInSAR. 56 meters of elevation errors were found in the flat area regardless of the usage and the resolution of DEM, as a result of InSAR analyzing with a pair of ERS tandem and 6 pairs of JERS-1 interferograms. In the mountain area, however, DInSAR with DEMs from SRTM-3 and the digital map was found to be very effective to reduce errors due to phase unwrapping procedure. Also errors due to low signal-to-noise ratio of radar images and atmospheric effect were attenuated in the DEMs generated from the stacking of 6 pairs of JERS-1. SAR interferometry with multiple pairs of SAR interferogram with low resolution DEM can be effectively used to enhance the resolution of DEM in terms of data processing time and cost.

트리 구조를 이용한 연관규칙의 효율적 탐색

김창오(Chang-Oh Kim),안광일(Kwang-Il Ahn),김성집(Seong-Jip Kim),김재련(Jae-Yearn Kim) 대한산업공학회 2001 대한산업공학회지 Vol.27 No.1

진료지침 : 낙상예방 진료지침

김광일 ( Kwang Il Kim ),정혜경 ( Hye Kyung Jung ),김창오 ( Chang Oh Kim ),김수경 ( Soo Kyung Kim ),조현호 ( Hyun Ho Cho ),김대열 ( Dae Yul Kim ),하용찬 ( Yong Chan Ha ),황성희 ( Sung Hee Hwang ),원장원 ( Chang Won Won ),임재영 ( J 대한내과학회 2015 대한내과학회지 Vol.89 No.6

Falls and fall-related injuries are common in older population and have deleterious effects to the quality of life or independence of daily living in the elderly. Falling is also associated with substantial morbidity, mortality, nursing home admission and the increase of medical costs. Because Korea has shown extreme demographic shift with its population aging at the fastest pace among developed country, assessment of fall risks and intervention to high risk population are getting more important. The guideline for prevention of falls was developed first by The Korean Association of Internal Medicine and The Korean Geriatric Society. This guideline was developed by adaptation process as evidence-based method; four guidelines were retrieved by systematic review and the Appraisal of Guidelines for Research and Evaluation II process, seven statements were made with the grading of evidence and recommendations followed the Grades of Recommendation, Assessment, Development, and Evaluation framework. Because falls result from various combinations of many factors, the guideline contains multidimensional assessment and multimodal strategy to prevent falls. This guideline was developed for not only primary physician but also patients and general population, therefore it provides detailed recommendations and concrete measures to assess the risk and prevent falls in older people. (Korean J Med 2015;89:752-780)

The Effect of Resist and Assist Torque of Hip Joint Motor-based Gait Assistance Robot on Gait Function in the Elderly

전형규(Hyung Gyu Jeon),정경환(Kyunghwan Jung),강병문(Byungmun Kang),김대은(DaeEun Kim),임윤묵(Yun Mook Lim),김광준(Kwang Joon Kim),김창오(Chang Oh Kim),이황재(Hwang-Jae Lee),김경록(Kyungrock Kim),김윤명(Yoon-Myung Kim) 대한운동학회 2022 아시아 운동학 학술지 Vol.24 No.4

OBJECTIVES The purpose of this study was to investigate the effects of assist and resistance torque on the spatiotemporal gait characteristics, and the symmetry and asymmetry of gait using a Gait Enhancing and Motivating System (GEMS) in the elderly. METHODS A cross-sectional and repeated measure design was used. A total of 18 participants (9 males, 9 females; age: 63.5 ± 5.02 years; mass: 64.26 ± 6.87 kg; height: 164.06 ± 7.15 cm) were recruited from a local community, and spatiotemporal gait data were collected with OptoGait system and GEMS. Spatiotemporal gait variables and differences between the dominant and non-dominant legs of these variables were assessed (step length, step time, stance phase, swing phase, single support, load response, pre swing phase, stride time, stride length, double support, cadence, and gait speed). The effects of three modes including normal, assist, and resist modes using GEMS were investigated twice for each participant on a 9-meter walkway. A one-way repeated measure analysis of variance followed by Bonferroni post-hoc tests was conducted. RESULTS The assist mode increased step time, swing phase, stride time and reduced stance phase, pre-swing phase, double support, cadence, and gait speed as compared to normal mode. The resist mode increased stance phase, load response, pre-swing phase, double support, cadence, and reduced step time, swing phase, and stride time. In dominant leg, assist mode showed increased step time and reduced pre-swing phase than normal mode, and greater step time than resist mode (p < 0.05). However, there was no effect of external torque on symmetry and asymmetry between both legs (p > 0.05). CONCLUSIONS The resistance and assist torque of GEMS alter spatiotemporal characteristics during the stance and swing phase of gait in the elderly. However, the resistance torque and assist torque of GEMS did not increase or decrease the gait asymmetry between the dominant and non-dominant legs.

주택 보급형 태양열 온수급탕 시스템의 효율향상에 대한 연구

김창오(C. O. Kim),정용우(Y. W. Chung),김진흥(J. H. Kim),정낙규(N. K. Chung),오율권(Y. G. Oh) 대한기계학회 2002 대한기계학회 기타 간행물 Vol.2002 No.11

General principles and perioperative management

김창오(Chang Oh Kim) 대한외과학회 2014 대한외과학회 학술대회 초록집 Vol.2014 No.11

저온잠열저장을 위한 TMA-물계 포접화합물의 과냉각 개선에 대한 연구

김창오(Kim Chang-Oh),김진흥(Kim Jin-Heung),정낙규(Chung Nak-Kyu) 한국태양에너지학회 2007 한국태양에너지학회 학술대회논문집 Vol.- No.-

This study aims to find out cooling characteristics of TMA(Tri-Methyl- Amine, (CH₃)₃N) 25wt%-water clathrate compound with ethanol(CH₃CH₂OH) such as supercooling, phase change temperature and specific heat. For this purpose, ethanol is added as per weight concentration and cooling experiment is performed at -6˜-8℃, cooling heat source temperature, and it leads the following result. (1) Phase change temperature is decreased due to freezing point depression phenomenon. Especially, it is minimized as 3.8℃ according to cooling source temperature in case that 0.5wt% of ethanol is added. (2) If 0.5wt% of ethanol is added, average supercooling degree is 0.9℃ and minimum supercooling is 0.8, 0.7℃ according to cooling heat source temperature. The restraint effect of supercooling is shown. (3) Specific heat shows tendency to decrease if ethanol is added. It is 3.013~3.048 ㎉/㎏℃ according to cooling heat source temperature if 0.5wt% of ethanol is added. Phase change temperature higher than that of water and inhibitory effect against supercooling can be confirmed through experimental study on cooling characteristics of TMA 25wt%-water clathrate compound by adding additive, ethanol. This can lead to shorten refrigerator operation time of low temperature latent heat storage system and improve COP of refrigerator and efficiency of overall system. Therefore energy can be saved and efficiency can be improved much more.