건설사업관리 지원을 위한 토목 BIM 개념 모형 수립

임상묵 ( Sang Muk Lim ),정근채 ( Keun Chae Jeong ) 충북대학교 건설기술연구소 2012 建設技術論文集 Vol.31 No.2

최근 토목 분야의 건설 프로젝트가 대영화, 복잡화, 되면서 건설사업관리(Construction Management; Cm)의 업무 난이도가 매우 높아지고 있다. 이에 몇몇 선진적인 프로젝트에서는 CM 업무의 지원을 위해 건설정보모델링기법(Building Information Modeling; BIM)의 도입을 꾀하고 있다. 본 연구에서는 CM의 6대 서비스 분야인 프로젝트관리, 원가관리, 공정관리, 품질관리, 프로젝트행정 및 계약관리, 안전관리 관점에서 BIM을 활용한 프로젝트를 분석함으로써, 토목 분야 BIM을 통해 CM 업무를 지원하기 위한 기능과 데이이터베이스를 정의함으로써, 건설사업관리 지원을 위한 BIM 개념 모형을 수립하였다. 본 연구에서 제안한 토목 BIM 개념 모형이 구현되어 건설 프로젝트에 적용된다면, CM 업무가 보다 체계적이고 용이하게 수행될 수 있을 것으로 기대한다. Recently, level of difficulty for the construction management (CM) becomes higher and higher, since construction projects become larger and more complicated. Therefore, some advanced projects start to introduce Building Information Modeling (BIM) for supporting CM services. In this paper, we survey BIM based projects from CM service viewpoints, such as Project Management, Cost Management, Time Management, Quality Management, Project and Contract Administration, and Safety Management, and then, we analyze problems and drawbacks of BIM and draw Improvement method for them, Base on the results from the case studies, we set up a conceptual BIM for be performed more systematically and easily if the proposed conceptual model will be implemented and applied to the construction projects in the area of civil engineering.

한국잔디에 대한 Prohexadione-calcium의 생장 억제 효과

임상묵(Sang Muk Lim),최봉수(Bong Su Choi),우선희(Sun Hee Woo),이철원(Chul Won Lee) 韓國雜草學會 2011 Weed&Turfgrass Science Vol.31 No.2

본 연구는 예초 직후에 prohexadione-calcium을 처리하여 잔디의 생장 실태를 조사하였다. 한국잔디로 조성된 잔디밭이나 골프장을 효과적으로 관리하기 위하여 한국잔디의 예초 직후 prohexadione-calcium의 농도를 달리하여 엽면 처리한 결과 무처리와 비교하여 잎의 생장이 현저히 감소되는 것으로 나타났으며 prohexadione-calcium의 1회 처리로도 그 효과가 처리후 50일까지 잎의 생장이 46~50% 정도 감소되는 것으로 나타났고, 엽폭도 처리농도가 높을수록 무처리에 비하여 좁아졌다. prohexadione-calcium 처리후 건물중의 변화를 보면 처리후 2주후부터 무처리에 비하여 현저하게 감소하는 것으로 나타났는데, 처리 농도가 높을수록 건물중이 작았으며 처리 40일까지도 건물중의 증가가 무처리에 비하여 유의하게 감소하는 것으로 나타났다. 또한 엽색도는 prohexadione-calcium의 처리구가 무처리구에 비하여 높았다. This experiment was carried out to investigate the growth responses of zoysiagrass (Zoysia japonica Steud.) as affected by prohexadione-calcium foliar application for the effective labour saving and cost down management in the lawn yard, field and golf course etc. The leaf growth of zoysiagrass treated with prohexadione-calcium one day after mowing was significantly slow compared to the untreated plot. And the effect was continued up to 50 days. The growth inhibition rate at the treated plot was 46 to 50% compared to untreated plot and the leaf widths treated with prohexadione-calcium were narrower than control plot. The change of leaf dry weight 10 days after prohexadione-calcium treated was significantly shown less speedy than untrated plot and the results were continued up to 40 days after application. The SPAD values of the leaf colour were increased in the treated plots and continued for 40 days more.

전산화 단층촬영에 사용되는 조영제의 부작용 발생에 대한 분석

임상묵(Sang Muk Lim),조영기(Young Ki Cho),구양수(Yang Soo Gu),이강우(Kang Woo Lee),송환수(Hwan Soo Song),강화원(Hwa Won Kang),김영빈(Young Bin Kim),임성훈(Sung Hoon Lim),온상구(Sang Gu On) 대한CT영상기술학회 2008 대한CT영상기술학회지 Vol.10 No.1

Purpose The objective of this article is to analyze the symptom of patients suffering the adverse reaction of contrast medium in CT test and the risk factor mat can cause adverse reaction in order to provide basic materials which contribute to find the method to reduce adverse reaction in advance. Materials and Methods Among the patients visiting university hospital from January to July, 2007, adults over 16 years old to whom contrast medium was applied into vein for CT test were chosen. Then, among them, 92 male and female patients who suffered the adverse reaction of contrast medium were selected as target. Analyzing backwardly the general property of testee recorded in the written consent for test which was received from patients or custodian before CT test and the former history of the adverse reaction of contrast medium, existence/unexistence of disease and the disease, the test result of patients (hypertension, allergy, asthma, medication adverse reaction, kidney disease, diabetes, digestive organ, respiratory organ, circulatory organ, nerve, hematogenesis, lymph, thyroid gland and other unidentified disease), the authors investigated the relation with adverse reaction and analyzed the risk factor of adverse reaction as per tested part, types of contrast, infusion quantity, infusion velocity in accordance with contrast medium applied to the testee. Further, the symptom of adverse reaction was analyzed in each type. Namely, actual number and percentage was analyzed in the division of dermal sensory system, respiratory organ, digestive organ, nerve system, circulatory organ, ophthalmologic system and so on. To analyze the risk factor of adverse reaction of testee after CT test, Chi-square test and simple/multiple regression analysis was adopted to diverse variables so as to analyze significance by using SPSS 10.0 statistical program. Results 1. In the general property, the division of sex was 36 men(39.1%) and 56 women (60.9%), showing no significant difference in the analysis of sex on the symptom of adverse reaction(p=0.132). In the aspect of age, those in 50~59 years old showed the highest rate of adverse reaction -29 persons (31.5%) and those under 19 years old showed the lowest rate of adverse reaction -1 person (1.1%). Thus, the age analysis in the symptom of adverse reaction also showed no statistically significant difference(p=0.204). The occurrence of adverse reaction in each part of body for test also showed no significant difference from the symptom of adverse reaction of contrast medium (p=0.137). 2. In the case of type of contrast medium (p=0.093), infusion quantity (p=0.279), infusion velocity (p=0.314), there was no statistically significant difference from the symptom of adverse re-action of contrast medium. In the product of A-1,54 persons (58.7%), 61 persons (66.3%) in 121-130cc, 37 persons (40.2%) in 2.6-3.0cc/sec, respectively showing the highest distribution, namely, the symptom of adverse reaction. In the former history of the contrast medium, 10 out of 92 persons(10.9%) were analyzed, thereby showing statistically significant difference(p=0.003). 3. In the analysis of adverse reaction of contrast medium as per history of disease, 9 patients(11%) of hypertension showed urticaria and itching, ex 7), 16 patients (19.5%) of allergic asthma showed urticaria and itching, ex 17) and flush, ex 5), 4 patients of medication adverse reaction (5.2%) showed flush, dermal edema, dizziness, ex 3), 3 patients(3.9%) of kidney disease showed urticaria and itching, ex 5), 32 patients(41.6%) of digestive organ disease, the highest distribution showed itching and urticaria, ex 30), flush, ex 11), 1 patient(1.3%) of nerve system disease showed urticaria and itching, dizziness, ex 2), 6 patients(7.8%) of thyroid gland disease showed urticaria and itching, ex 6), dyspnea, ex 2). Thus, the symptom of adverse reaction of contrast medium as per history of disease showed statistically significant difference(p=

위암 진단을 위한 복부CT 검사시 자세 변경에 따른 Air+Water 경구조영제 사용의 유용성

이득열(Deuk Real Lee),임상묵(Sang Muk Lim),강화원(Hwa Won Gang),유대준(Dae Jun Yoo),김대현(Dae Hyun Kim) 대한전산화단층기술학회 2013 대한CT영상기술학회지 Vol.15 No.1

목적 : 위암 진단을 위한 복부CT 검사시 경구조영제로서 기존에 사용하던 발포제 2포 대신 발포제 1포와 물을 이용하여 환자의 자세변화에 따른 유용성에 대하여 알아보고자 하였다. 대상 및 방법 : 대상은 실험군(Group A)은 2012년 10월부터 2012년 12월까지 위암 진단을 위해 복부 CT를 시행한 총인원 117명(남자:76명,여자:41명)으로 평균연령은 59.7세 였다. 대조군(Group B)은 2012년 7월부터 2012년 9월까지 위암 진단을 위해 복부 CT를 시행한 총인원 100명(남자:66명,여자:34명)으로 평균연령은 61.2세 였다. 검사장비는 Siemens사의 Sensation 16, Defenition, Defenition AS+장비를 사용하였고 위 확장용 경구조영제는 태준제약의 탑발포지(4g)과 물을 사용하였다. 검사방법은 Group A는 발포제 1포와 물 300ml, Group B는 발포제 2포를 경구조영제로 먹은 후 pre, artery, portal phase는 좌후사위 자세에서 검사하였고 delay phase는 우측와위 자세에서 검사하였다. 두 Group의 위확장정도 비교평가는 10년 이상 경력의 CT전문 방사선사 3명이 PACS를 통해 poor : 1, fair : 2, good : 3, excellent : 4로 평가하였다. 영상의 정성적 평가는 Group B의 위암 판정을 받은 20명을 복부전문 영상의학과 전문의 1명과 위암전문 소화기외과 전문의 1명이 PACS를 통해 후향적으로 물과 공기의 병변과의 대조도 정도를 평가하였고 공기가 좋으면 1, 같으면 2, 물이 좋으면 3으로 3단계로 평가하였다. 결과 : 첫 번째 위확장정도 평가는 Group A에서 poor가 평균 6.3명, fair가 평균 17.7명, good은 49.7명, excellent는 43.3명 이었고 전체평균은 3.11로 나타났다. Group B는 poor가 평균 3명, fair가 평균 14.7명, good은 47.7명, excellent는 34.7명 이었고 전체평균은 3.14으로 나타났다. 두 그룹의 차이는 발포제로만 검사한 Group B가 평균 0.03 높은것으로 나타났으며 T-test를 통한 두 그룹의 차이는 없었다. 두 번째 공기와 물의 병변과의 대조도 차이는 공기가 좋은 경우는 8명으로 전체의 40%로 나타났고, 같은경우는 6명, 물이 좋은 경우는 6명으로 각각 30%로 나타났다. 결론 : 경구조영제로 발포제와 물을 동시에 사용하여 검사하는 방법은 기존 발포제로만 한 검사와 비교해서 좋은 위확장정도는 유지하면서 좌후사위 자세에서는 antrum에 공기로 채워진 영상과 fundus에는 물이 채워진 영상, 우측와위 자세에서는 antrum에 물이 채워진 영상과 fundus에는 공기가 채워진 영상을 얻을 수 있어서 공기와 물의 조영효과를 동시에 평가 할 수 있어서 환자의 병변을 평가하는데 좀 더 도움을 줄 수 있을 것으로 생각된다. Purpose : It was to identify the usefulness of a effervescent granule and water instead of two effervescent granules as oral contrast media in Abdomen CT for diagnosis of Gastric cancer according to positional changes. Material and methods : Experimental group subjects (Group A) were 117 patients (76 males and 41 females) who had Abdomen CT for gastric cancer diagnosis from October to December in 2012. Mean age was 59.7. Control group subjects (Group B) were 100 patients (66 males and 34 females) who had Abdomen CT for gastric cancer diagnosis from July to September in 2012. Mean age was 61.2. For the examination, Sensation 16, Defenition, and Defenition AS+ by Siemens were used, and for oral contrast media to expand stomach Top effervescent-G (4g) by Taejoon Pharm and water were used. Group A had a effervescent granule and 300ml water, and Group B had two effervescent granules as oral contrast media. They were examined in LPO position for pre, artery and portal phase and in Rt decubitus position for delay phase. To compare and evaluate the gastric distension level of two groups, 3 CT radiology technologists with more than 10 years’ experiences were asked to evaluate as poor:1, fair:2, good:3, excellent:4. For the qualitative evaluation of images, a Abdominal specialized radiologist and a stomach cancer specialized digestive surgeon evaluated contrast of water and air with lesions on 20 gastric cancer diagnosed patients in Group B retrospectively through PACS. They marked 1 when water was better, 2 when they were equal, and 3 when water was better. Results : In the first gastric distension level test, Group A had 6.3 as poor, 17.7 as fair, 49.7 as good, and 43.3 as excellent, which made the average 3.11. Group B had 3 as poor, 14.7 as fair, 47.7 as good, and 34.7 as excellent, which made the average 3.14. Group B using effervescent granules only showed 0.03 higher results than Group A but there was no significant difference between two groups through T-test. Second, in the contrast of water and water with lesions, air was better in 8 subjects (40%), equal was 6 (30%) and water was better in 6 (30%). Conclusion : When using effervescent granule and water at the same time as oral contrast media, it maintained gastric distension level and provided various images such as air-fⅢed antrum and water-fⅢed fundus image at LPO position and water-fⅢed antrum and air-fⅢed fundus image at Rt decubitus position. As it allows evaluating the contrast effects of water and air at the same time, it may help to evaluate lesions of patients better.

복부 전산화단층촬영에서 Bolus triggering기법을 이용한 체질량 지수 변화에 따른 최적의 지연시간 연구

정재연(Jeong Jae yeon),김홍석(Kim Hong suck),최진영(Choi Jin Young),임상묵(Lim Sang Muk),조영기(Kim Dae Hyun),김대현(Cho Young Ki) 대한CT영상기술학회 2013 대한CT영상기술학회지 Vol.15 No.1

목적 조영증강 CT 검사에서 병변의 진단과 조영제 사용 등에 많은 영향을 주고 있는 조영증강 시간을 환자의 성별, 연령별, 비만, 고혈압 유무 등의 체질량지수에 따라 복부 대동맥에서 Bolus triggering 기법을 이용하여 평균 도달 시간이 사람마다 각각 다르게 나타난다는 점을 착안하여 조영 시간에 영향을 주는 인자들에 대해 살펴보고 환자방어의 최적화를 위한 그들의 상관관계에 대해 유용성을 알아보고자 연구하였다. 대상 및 방법 2010년 8월부터 2011년 8월까지 12개월간 본원에서 복부 전산화단층촬영을 시행한 환자 중 장비에 내장된 응용 소프트웨어 Bolus triggering 기법을 이용하여 검사를 시행한 환자를 대상으로 하였다. 정상 환자군에서 남, 여 각 50명씩 100명, 비만 환자군에서 남, 여 각 50명씩 100명, 고혈압 환자군에서 남, 여 각 50명씩 100명, 비만과 고혈압이 동시에 있는 환자군에서는 남, 여 각 40명씩 80명이었다. 스캔 범위를 결정한 다음 20G로 정맥내 주사를 확보하여 조영제 양을 3.5 ml/s, 2 ml/kg의 주입속도로 주입하고 난 후 생리식염수 20 ml를 같은 주입속도 비율로 주입하여 균일한 조영증강이 정점에 도달하게 하였다. 복부 대동맥에서 Bolus triggering을 실시하여 100 HU되는 시점으로부터 15초 후 영상을 얻기 시작하였다. 선량측정은 전체 스캔 선량을 표시하는 DLP값을 이용하여 비교하였다. 결과 연령별 분석에서 연령이 증가할수록 모니터링 횟수가 증가되었고 평균 도달 시간이 늦어지는 것을 알 수 있었으며 통계적으로 유의한 차이를 보였다(p= .001). 성별 분석에서는 남자군이 여자군보다 모니터링 횟수가 증가되었고 평균 도달 시간이 늦어지는 것을 알 수 있었으며 통계적으로 유의한 차이를 보였다(p= .001). 환자의 특성 중 100 HU값의 조영증강 시간은 체질량지수 측정 결과 비만 환자군 또는 고혈압 환자군 보다는 비만과 고혈압을 동시에 가지고 있는 환자군에서 모니터링 횟수가 증가되었고 평균 도달 시간이 늦어지는 것으로 나타냈다(p= .001). 기존의 모니터링 스캔 지연시간 15초를 비만 환자나 질환의 유무 및 정도에 따라 조절하여 모니터링 횟수 분석을 통해 적용했을 때 평균 4.4회로 DLP값 0.214 mSv였고, 모니터링 시작 시간을 4초 후에 시작함으로써 DLP값 0.214 mSv의 방사선 노출을 감소시킬 수 있었다. 비만인 남자 환자군에서 평균 5.4회로 DLP값 0.283mSv, 여자 환자군에서 평균 4.38회로 DLP값 0.212 mSv로 나타냈다. 고혈압인 남자 환자군에서 평균 5.18회로 DLP값 0.268 mSv, 여자 환자군에서 평균 3.62회로 DLP값 0.182 mSv로 나타났다. 결론 환자의 특성 중 100 HU값의 조영증강 시간은 연령이 증가할수록, 성별이 여자군 보다는 남자군에서, 체질량지수 측정결과 비만과 고혈압을 동시에 지닌 환자군에서 조영증강 시간이 증가하는 것으로 나타났다. 본 실험에서와 같이 모니터링 자료를 관리하여 환자 개개인의 특성을 알고 접근한다면 1년에 최소 2~3번까지 추적검사를 하는 환자에게 피폭되는 선량값을 줄일 수 있을 것으로 사료된다. Ⅰ. Purpose The purpose of this study is to review the factors influencing the contrast time and to identify the usefulness of their correlations of the factors for the optimization of patient protection, considering that in contrast enhancement CT, contrast enhancement time influences much on the lesion diagnosis and the use of contrast agent and average arrival time varies among people by sex, age, obesity, BMI and hypertension. In this study, it was measured at abdominal aorta using Bolus triggering technique. Ⅱ. Meterial and Methods The subjects were the patients who had a test using Bolus triggering technique among the patients who had abdominal Computed Tomography in Chonbuk National University Hospital for 12 months from August 2010 to August 2011. Subjects were selected as 100 people (50 males and females respectively) from normal group, 100 people (50 males and females respectively) from the group of hypertension patients, and 80 people (40 males and females respectively) from the group with obesity and hypertension together. After determining the scan scope, contrast agent was injected at 3.5 ml/s or 2 ml/kg by securing the intravenous injection with 20 gauge and 20 ml physiological saline was injected at the same injection speed to make the even contrast enhancement arrive at peak. Performing Bolus triggering at abdominal aorta, images were acquired from 15 seconds after 100HU. Dosimetry was compared using DLP value showing the total scan dose. Ⅲ. Result From the analysis by age, the times of monitoring increased with the increase of age, average arrival time became delayed, and the difference was statistically significant (p= .001). In the analysis by sex, male patients had more monitoring sessions than female patients, average arrival time was delayed, and the difference was also statistically significant (p= .001). From the characteristics of the patients, contrast enhancement time of 100HU was seen more frequently among the group with obesity and hypertension together than the group of obesity or hypertension and the arrival time was later in obese and hypertension group (p= .001). When applying by coordinating the conventional monitoring scan delay time (15 seconds) according to the obesity or the presence of a disease and analyzing the monitoring times, the average monitoring times was 4.4 or 0.214 mSv in DLP value. By adjusting the monitoring starting time to 4 seconds late, radioactive exposure such as DLP value of 0.214 mSv could be reduced. It was shown as 5.4 times and 0.283 mSv of DLP in obese male patients, and 4.38 times and 0.212 mSv of DLP in obese female patients. It was shown as 5.18 times and 0.268 mSv of DLP in hypertension male patients, and 3.62 times and 0.182 mSv of DLP in hypertension female patients. Ⅳ. Conclusions Contrast enhancement time of 100 HU increased in the patients who were older males and had obesity and hypertension together. If approaching the characteristics of each patient by managing the monitoring data just as in this experiment, we may be able to reduce the radioactive dose that the patients would have who should have at least 2-3 times follow up treatment a year.

MDCT장비별 관전압 변화에 의한 HRCT의 선량과 Noise변화

이득열(Deuk Youl Lee),장양선(Yang Seon Jang),김영빈(Yeong Bin Kim),임상묵(Sang Muk Lim),이광원(Kwang Won Lee),조영기(Young Gi Jo) 대한CT영상기술학회 2012 대한CT영상기술학회지 Vol.14 No.1

목적 흉부CT 중 가장 많이 시행되고 있는 HRCT는 고관전압의 사용으로 피폭선량이 높아 이를 대상으로 관전압의 변화에 따라 피폭선량과 화질의 변화를 알아보고자 하며 발달된 MDCT의 장비별로도 어떠한 차이가 있는지 알아보고자 하였다. 대상 및 방법 본 연구는 Sierrrns사의 MD-16, 64, 128 ct장비의 고정관전류값, AEC의 reference mAs, pitch, kernel값 등은 모두 동일하게 하였고 장비 고유의 Collimator와 rotation time은 같게 할 수 없어 단순비교를 위해 장비고유의 값으로 설정하였고, 장비별로 관전압을 100 kVp, 120 kVp, 140 kVp로 변화시키면서 고정관전류 경우와 AEC 경우를 실험하였다. Rando phantom을 사용하여 각 영상의 Noise를 측정하였고, 선량측정은 장비에서 측정되는 DLP값으로 전체적인 유효선량을 나타내었으며 실질적으로 폐가 받는 유효선량은 Glass Dosimeter를 사용하여 측정하였다. 결과 동일 관전압에서 장비별 Noise 변화는 MD-64CT에 대해 16CT는 31.2% 증가, 128 CT는 19,4%로 감소하였다. Noise의 변화는 관전압이 100kVp에서 120kVp 증가 시 MD-6CT는 7.8%, 64CT는 7%, 128 CT는 3.9% 감소하였고, 120kVp에서 140kVp 증가 시 16CT는 6.5%, 64 CT는 4.6%, 128 CT는 3.2% 감소하였다. 장비별 전체 유효선량은 고정관전류 경우 MD-64CT보다 16CT는 5.3% 증가, 128CT는 2.9% 감소하였고, 폐의 유효선량도 8.9% 증가, 11,1% 감소하였다. MD-16CT의 관전압이 140kVp에서 120kVp 감소에 따른 전체 유효선량변화는 28.3%, 폐의 유효선량은 32.2% 감소하였고, 120kVp에서 100kVp 감소 시 31.1%, 26.4% 감소하였다. MD-64CT의 관전압이 140kVp에서 120kVp 감소에 따른 전체 유효선량변화는 33.1%, 폐의 유효선량은 33.9% 감소하였고, 120kVp에서 100kVp 감소 시 41.8%, 34.6% 감소였다. MD-128CT의 관전압이 140kVp에서 120kVp 감소에 따른 전체 유효선량변화는 34%, 폐의 유효전량은 33.3% 감소하였고, 120kVp에서 100kVp 감소 시 41.8%, 36.2% 감소하였다. 결론 본 연구를 통하여 관전압의 감소에 의한 선량감소효과가 매우 크다는 사실을 알고 MDCT장비별로 영상의 진단적 가치를 저하시키지 않는 범위 내에서 적정한 Noise값을 유지하며 관전압을 낮추어 사용한다면 환자피폭선량을 최소한으로 줄일 수 있을거라 생각된다. I. Purpose HRCT, the most commonly used chest CT, uses a high tube voltage and therefore exposes the subject to a high dose. Thus, this study purposed to examine the variation of exposure dose and image quality according to tube voltage and to analyze differences among advanced MDCT. II. Material and method This study set equally the fixed tube currency, AEC reference mAs, pitch and kernel value of MD-16, 64 and 12.8 CT manufactured by Siemens, and because collimator and rotation time could net be set equally they were set to the values specific to each MDCT for simple comparison. For each MDCT, we changed tube voltage from 100 kVp to 120 kVp and 140 kVp, and conducted experiments in case of fixed tube currency and in case of AEC. The noise of each image was measured using a Rando phantom, and for exposure doses, overall effective dose was presented in DLP and effective dose on the chest was measured with glass dosimeter. III. Result Af. the same tube voltage, noise was 31.2% higher in 16CT and 19.4% lower in 128 CT compared to that in MD-64CT. When tube voltage increased from 100 kVp to 120kVp, noise increased by 7.8% in .MD-16CT, 7% in 64CT, and 3.9% in 128 CT, and when it increased from 120kVp to 140kVp, noise increased by 6.5% in 16 CT, 4.6% in 64 CT, and 3.2% in 12.8 CT. Overall effective dose under fixed tube currency was 5.3% higher in 16CT and 2.9% lower in 12.8CT than that in MD-64CT, and effective dose on the chest was 8.9% higher and 11.1% lower, respectively. When the tube voltage of .MD-16CT decreased from 140kVp to 120 kVp, overall effective dose decreased by 28.3% and effective dose on the chest decreased by 32. 2%, and when the tube voltage decreased from 120 kVp to 100 kVp, they decreased by 31.1% and 26.4%, respectively. When the tube voltage of MD-64CT decreased from 140 kVp to 120 kVp, overall effective dose decreased by 33.1% and effective dose on the chest decreased by 33.9%, and when the tube voltage decreased from 120kVp to 100kVp, they decreased by 41.8% and 34.6%, respectively. When the tube voltage of .MD-128CT decreased from 140 kVp to 120 kVp, overall effective dose decreased by 34% and effective dose on the chest decreased by 33.3%, and when the tube voltage decreased from 120kVp to 100 kVp, they decreased by 41.8% and 36.2%, respectively. IV. Conclusion From the results of this study, we found that the decrease of tube voltage is highly effective in reducing exposure dose, and believe to minimize patients’ exposure dose by lowering tube voltage while maintaining an adequate noise level within the scope of not degrading the diagnostic value of images in each MDCT.

건설사업관리 지원을 위한 토목 BIM 개념 모형 수립

임상묵, 정근채 충북대학교 건설기술연구소 2012 建設技術論文集 Vol.31 No.2

본문참고.