2인용 치료병실 안전성 평가

이경재,조현덕,오창범,고길만,박영재,이인원,안희용,Lee, Kyung-Jae,Cho, Hyun-Duck,Oh, Chang-Bum,Ko, Kil-Man,Park, Young-Jae,Lee, In-Won,Ahn, Hee-Yong 대한핵의학기술학회 2011 핵의학 기술 Vol.15 No.1

유럽 및 미국에서는 다인용 치료병실을 사용하고 있는 실정이다. 이에 서울대학교병원에서 현재 1인용 치료병실로 사용하고 있는 병실을 2인용 치료병실로 운영할 때 안전성에 대해 알아보고자 한다. 서울대학교병원 기존 치료병실에 침대와 침대 사이 차폐벽을 설치하여 2인용 치료병실로 운영할 경우, 상대방 환자로부터 방출되는 감마선의 산란에 의한 외부피폭과 상대방 환자에 의해 발생되는 오염으로 인한 외부 및 내부피폭을 평가하였다. 2인용 치료병실의 안전성 평가를 위해 외부 및 내부피폭을 평가하였을 때 원자력법에서 고시하는 '진료환자의 격리 수량, 5 mSv'이하의 피폭을 받게 됨을 알 수 있었다. 그리고 환자들의 피폭관리방안을 수립하여 교육 및 관리함으로써 환자 상호 간의 불필요한 피폭을 방지할 수 있다는 것을 알 수 있었다. 갑상선암 환자의 증가에 따라 치료병실 이용하는 환자가 적체되고 있는 추세이다. 이에 국제적 추세에 발맞춰 현행 1인용 치료병실을 2인용 치료병실로 개선함으로써 비용절감 및 관리의 효율성을 증대할 수 있으며 환자의 소외감과 고립감을 해소하여 치료효과를 높일 수 있다. Purpose: Europe and U.S use multi-bed therapy rooms. Hereupon, this study aims to examine the safety when current one-bed therapy rooms in Seoul National University Hospital is changed into two-bed ones. Materials and Methods: This study evaluated external exposure by gamma radiation emitted from other patients and internal and external exposure caused by pollutions from other patients in case that Seoul National University Hospital installs a shielding wall between beds in existing therapy rooms. Results: When internal and external exposure was evaluated to evaluate safety of two-bed hospital rooms, 'isolation amount of patients' 5mSv exposure or below is received according to the Atomic Energy Act. Conclusion: With the increasing number of patients with thyoid cancer, patients using therapy rooms are on the rise. Therefore, improving one-person therapy rooms to two-person ones in line with international trend would increase cost reduction and management efficiency, and patients' alienation and isolation can be reduced to increase healing effects.

Warping을 이용한 움직임 보상을 통한 3차원 의료 영상의 압축

소윤성,조현덕,김종효,나종범,So, Yun-Sung,Cho, Hyun-Duck,Kim, Jong-Hyo,Ra, Jong-Beom 대한의용생체공학회 1997 의공학회지 Vol.18 No.3

본 논문에서는 3차원 의료 영상의 압축을 위한 인터프레임 부호화 방법을 제안한다. 슬라이스 사이의 변화를 뼈나 조직의 움직임으로 간주하여 움직임 보상 기법을 통해 이전 프레임으로부터 현재 프레임을 예측하고, 변환 부호화를 사용하여 오차 영상을 압축한다. 의료 영상의 슬라이스 사이의 복잡한 변화를 잘 예측하기 위해 동영상 부호화에서 가장 널리 사용되는 블럭 정합 알고리즘 (BMA) 대신 bilinear 변환을 통한 영상 warping을 사용하였다. 이 warping 방법은 슬라이스 사이에서 object가 없어지는 경우 예측 성능이 저하되는데, 이러한 단점을 보완하기 위해 블럭 겹침 움직임 보상 (OBMC) 기법을 결합하였다. 움직임 보상된 오차 영상의 부호화에는 EZW 부호화를 사용하였고, 이 때 각 프레임의 wavelet 계수의 양자화 오차를 동일하게 하여 프레임마다 일정한 화질을 얻도록 하였다. 모의 실험에서 warping을 사용한 인터프레임 부호화는 각 프레임을 독립적으로 부호화하는 방식보다 높은 압축 성능을 보였고, OBMC를 결합함으로써 warping만을 사용했을 때보다 성능이 더 개선되었다. In this paper, an interframe coding method for volumetric medical images is proposed. By treating interslice variations as the motion of bones or tissues, we use the motion compensation (MC) technique to predict the current frame from the previous frame. Instead of a block matching algorithm (BMA), which is the most common motion estimation (ME) algorithm in video coding, image warping with biolinear transformation has been suggested to predict complex interslice object variation in medical images. When an object disappears between slices, however, warping prediction has poor performance. In order to overcome this drawback, an overlapped block motion compensation (OBMC) technique is combined with carping prediction. Motion compensated residual images are then encoded by using an embedded zerotree wavelet (EZW) coder with small modification for consistent quality of reconstructed images. The experimental results show that the interframe coding suing warping prediction provides better performance compared with interframe coding, and the OBMC scheme gives some additional improvement over the warping-only MC method.

자동차 HUD 표시장치의 인식특성에 관한 연구

김병우,조현덕,이영석,Kim, Byeong-Woo,Cho, Hyun-Duck,Lee, Young-Suk 한국반도체디스플레이기술학회 2008 반도체디스플레이기술학회지 Vol.7 No.3

The Paper presents some potential new uses for Head-Up Displays (HUDs) in vehicular applications, where the information conveyed to the driver goes well beyond the content of today's production HUDs. Such information potentially related to the use of cellular telephones, navigation systems, vehicle to roadside communications systems, and many others. Improvements in flat panel display technologies are enabling the presentation of larger, more reconfigurable, more daylight-viewable HUD images. In addition, A Formal test and evaluation is proposed to ensure that new information displays support the driver tasks. The above developments suggest increased future opportunities for HUDs to present useful information in an as-needed, eyes-on-the-road manner.

참치 기름담금 통조림의 Fο - 값 설정에 관한 연구

한봉호,조현덕,유홍식,김상호,정윤수 ( Bong Ho Han,Hyun Duck Cho,Hong Sik Yu,Sang Ho Kim,Youn Soo Chung ) 한국수산과학회 1994 한국수산과학회지 Vol.27 No.6

F_0-values of the canned tuna in cottonseed oil (CTCO) were investigated under different sterilizing conditions to optimize the energy consumption and microbiological safety. The F_0-values were measured using a microcomputer based technique. The exact cold point was not the volumetric center of the cans, and it was located in the center of meat mass in can which had ca. 6% of head space. Location of the test cans in retort showed no remarkable influence on the F_0-values when the cans were jumble loaded. The process time before sterilization should be shortened as much as possible to prevent the contamination of microorganisms. Thermophilic spore forming bacteria found from raw and precooked tuna were Bacillus subtilis, Bacillus cereus and Bacillus pasteurii, and the most heat resistant was Bacillus subtilis. The rational F_0-value for the CTCO obtained from the preservation test was regarded as 6min.

고용량 방사성옥소 치료 병실의 최대치 산출

이경재,조현덕,고길만,박영재,이인원,Lee, Kyung-Jae,Cho, Hyun-Duck,Ko, Kil-Man,Park, Young-Jae,Lee, In-Won 대한핵의학기술학회 2010 핵의학 기술 Vol.14 No.1

갑상선암 환자가 증가함에 따라 고용량 방사성옥소 치료환자 또한 적체되고 있는 추세이다. 따라서 현재 시설의 수용 능력을 고려하여 치료할 수 있는 병실의 최대치를 산출해 보고자 한다. 본원에 입원하는 고용량 방사성옥소 치료 환자의 방출 오 폐수량과 오 폐수의 방사능을 측정하고 고용량 방사성옥소 치료 병실에서 대기 중으로 방출하는 공기 중의 방사능 농도를 측정한다. 측정된 오 폐수의 방사능과 방출하는 공기 중의 농도가 교육과학기술부에서 고시하는 기준인 배수 중의 배출 관리 기준 30 Bq/L 및 배기 중의 배출관리기준 3 $Bq/m^3$을 만족할 때 치료 가능한 병실의 최대치를 계산한다. 가장 보수적인 수치로 계산하여 환자 1명을 치료할 경우 배출되는 오 폐수의 평균 방사능의 농도는 8 MBq/L였으며, 정화조에서 117일의 감쇠 시간을 거친 후의 평균 방사능의 농도는 29.5 Bq/L였다. 환자 2명을 치료할 경우 배출되는 오 폐수의 평균 방사능의 농도는 16 MBq/L였으며, 정화조에서 70일의 감쇠 시간을 거친 후의 평균 방사능의 농도는 29.7 Bq/L였다. 또한 같은 조건일 경우 치료 병실에서 RI 배기 filter를 통과하여 방출된 공기 중의 방사능 농도는 0.38 $Bq/m^3$였다. 수용 능력을 고려하여 치료할 수 있는 고용량 방사성옥소 치료 병실의 최대치를 산출하여 현재의 시설에 적용하고 병실 내 구조개선 등으로 2인실로 운영한다면 적체되어 있는 환자의 치료 대기 기간을 단축할 수 있으리라 사료된다. Purpose: According to increment of thyroid cancer recently, patients of high dose radioiodine therapy were accumulated. Taking into consideration the acceptance capability in the current facility, this study is to calculate the maximum value of high dose radioiodine therapy in patients for treatment. Materials and Methods: The amount and radioactivity of waste water discharged from high dose radioiodine therapy in patients admitted at present hospital as well as the radiation density of the air released into the atmosphere from the high dose radioiodine therapy ward were measured. When the calculated waste water's radiation and its density in the released air satisfies the standard (management standard for discharge into water supply 30 Bq/L, management standard for release into air 3 $Bq/m^3$) set by the Ministry of Education, Science and Technology, the maximum value of treatable high dose radioiodine therapy in patients was calculated. Results: When we calculated in a conservative view, the average density of radiation of waste water discharged from treating high dose radioiodine therapy one patient was 8 MBq/L and after 117 days of diminution in the water-purifier tank, it was 29.5 Bq/L. Also, the average density of radiation of waste water discharged from treating high dose radioiodine therapy two patients was 16 MBq/L and after 70 days of diminution in the water-purifier tank, it was 29.7 Bq/L. Under the same conditions, the density of radiation released into air through RI Ventilation Filter from the radioiodine therapy ward was 0.38 $Bq/m^3$. Conclusion: The maximum value of high dose radioiodine therapy in patients that can be treated within the acceptance capability was calculated and applied to the current facility, and if double rooms are managed by improving the ward structure, it would be possible to reduce the accumulated treatment waiting period for radioiodine therapy in patients.

자동차 모의 주행 환경 센서 기능 검지 기술 개발

윤상구(Sang-Goo Yoon),김영형(Young-Hyung Kim),조현덕(Hyun-Duck Cho),정치영(Chi-Young Jung),지연정(Yeon-Jeong Ji) 한국정보기술학회 2022 Proceedings of KIIT Conference Vol.2022 No.6

Sensor Fusion을 이용한 전자식 조향장치의 Fail Safety 연구

金?禹(Byeong-Woo Kim),許眞(Jin Her),趙賢德(Hyun-Duck Cho),李永碩(Young-Seok Lee) 대한전기학회 2008 전기학회논문지 Vol.57 No.8

A Steer-by-Wire system has so many advantages comparing with conventional mechanical steering system that it is expected to take key role in future environment friendly vehicle and intelligent transportation system. The mechanical connection between the hand wheel and the front axle will become obsolete. SBW system provides many benefits in terms of functionality, and at the same time present significant challenges - fault tolerant, fail safety - too. In this paper, failure analysis of SBW system will be performed and than sensor fusion technique will be proposed for fail safety of SBW system. A sensor fusion logic of steering angle sensor by using steering angle sensor, torque sensor and rack position sensor will be developed and simulated by fault injection simulation.

자동차 제어기의 내구수명 평가방안 연구

金?禹(Byeong-Woo Kim),崔範進(Beom-Jin Choi),趙賢德(Hyun-Duck Cho),李都熙(Do-Hee Lee) 대한전기학회 2008 전기학회논문지 Vol.57 No.2

In order to assess the reliability of the electronics control unit for vehicles, accelerated life test model and procedure are developed. By using this method, failure mechanism and life distribution are analyzed. The main results are as follows : ⅰ) the main failure mechanism is degradation failure that is, junction destruction of a semiconductor resin by high temperature. ⅱ) the life distribution of the electronics control unit for vehicles is fitted well to Weibull life distribution and the accelerated life model of that is fitted well to Arrhenius model. ⅲ) at the result of the life distribution, accelerated life test method is developed, and test time for life assessment will be shortened by 5,000 hours by this test method.

FD FAN에서 링크식을 대체한 기어식 베인 댐퍼의 개발

장성철(Sung-Cheol Jang),남태희(Tae-Hee Nam),정휘원(Hee-Won Jung),윤강로(Gang-Ro Yoon),조현덕(Hyun-Duck Cho),김남경(Nma-Kyung Kim) 한국기계가공학회 2007 한국기계가공학회 춘추계학술대회 논문집 Vol.2007 No.-

This study shows a numerical method to predict gear type vane damper in the forced draft fan. The simulation approach with 3-D FEM program(MSC. MARC) for gear type vane damper, gear and pinion driving simulation is in good agrement with it in tendency. Finally, we compared the gear driving result with simulation. It is the objective of the present study to identify a nonlinear flow rate control of gear type vane damper and to suggest a damper shape with a linear flow rate control. This study is related to the development of gear type vane damper change link type in forced draft fan.

회전형 2중 완충 캐스터의 개발

김영수(Young-Soo Kim),권용원(Young-Won Kwon),박중호(Joo-Ho Park),윤소남(So-Nam Yoon),함영복(Young-Bok Ham),조현덕(Hyun-Duck Cho),장성철(Sung-Cheol Jang) 한국생산제조학회 2012 한국생산제조시스템학회 학술발표대회 논문집 Vol.2012 No.4