치과용 캐드 / 캠의 현재와 미래

허영준 대한치과재료학회 2010 대한치과기재학회 학술대회 Vol.2010 No.4

마우스 CT26 종양에서 Tc-99m 표지 플루란유도체의 저류 특성

허영준,송호천,범희승,나건,김성민 대한핵의학회 2003 핵의학 분자영상 Vol.37 No.6

배경: 플루니유도체(PD)로 만든 나노입자는 이온강도에 다라 뭉치는 수용성겔이다. 본 연구에는 PD가 방사성핵종을 종양 조직 내에 효과적으로 머무르게 할 수 있는지 알아보고자 하였다. 방법: 네 종류의 PD 즉, pullulan acetate (PA), succinylated PA(SPA), PA-DTPA와 SPA-DTPA 결합체를 합성한 후 테크네슘-99m(Tc-99m)으로 표지하고 표지효율을 측정하였다. Balb/c 생쥐에 CT26 대장암세포를 피하주사하고 2주 후에 Tc-99m 표지 PD(Tc-PD)를 종양 내에 주사하였다. 주사직후와 30분, 1, 2, 4, 12시간 후에 감마카메라로 생쥐를 촬영하여 종양 내의 Tc-PD의 저류율을 측정하였다. 종양크기에 따라 각각의 암의 직경이 5mm와 10 mm일대 Tc-99mper-technctate와 Tc-99m 표지 PA를 종양 내 주사하여, 주사 직후 1시간 동적영상을 얻고, 1시간, 2시간, 3시간 그리고 4시간 후에 감마카메라로 생쥐를 촬영하여 종양 내의 저류율을 측정하였다. 결과: PA, SPA, PA-DTPA 및 SPA-DTPA의 Tc-99m 표지율은 각각 94.5±5.9%, 97.8±3.5% 94.2±3.8%, 92.5±62.%로 서로간에 유의한 차이가 없었다 (p>0.05). Tc-99m-PA와 Tc-99m-PA-DTPA의 %RR은 대조군에 비해 의의있게 높았으나(p<0.05), SPA는 4시간까지 그리고 SP-DTPA는 2시간가지만 대조군보다 %RR이 높았을 뿐 그 이후에는 대조군과 유사한 %RR을 보였다. 종양의 크기에 따라 PA군에서 측정한 저류율은 대조군보다는 의의있게 높았으나, 직경이 5 mm와 10 mm일 때의 저류율 간에는 차이가 없었다. 결론: PD가 종양 조직 내에 저류될 수 있음을 알았으며, 종양 크기에 따른 저류율의 차이는 없었다. 향후 PD와 치료용 방사성핵종을 이용한 종양치료에 활용할 가능성을 기대할 수 있을 것으로 사료되었다. Objective: Pullulan derivatives (PD) can be used to make self-assembled hydrogel nanoparticles which are responsive to ionic strength. The aim of this study is to evaluate the potential of PD as a retaining carrier of radioisotope inside tumors. Materials and Methods: Four types of PD were evaluated which included pullulan acetate (PA), succinylated PA (SPA), PA-DTPA and SPA-DTPA conjugates. They were radiolabeled with Tc-99m. Labelling efficiencies were determined at 30 min, 1, 2, 4 and 12 hours after radiolabeling. CT-26 colon cancer cells were subcutaneously injected into Balb/c mice. After 2 weeks of subcutaneous injection, Tc-99m-labelled PD (Tc-99m-PD)were injected into the tumors. Whole body images of mice were obtained at 30 min, 1, 2, and 12 hr after intratumoral injection. All twenty mice were grouped into four groups by largest diameter: control A (largest diameter = 5 mm, n = 5), control B (largest diameter = 10 mm, n = 5), pullulan A (largest diameter = 5 mm, n = 5), pllulan B (largest diameter = 10 diameter = 10 mm, n = 5), pullulan A (largest diameter = 5 mm, n = 5), pllulan B (largest diameter = 10mm, n = 51. Dynamic images were obtained for 1 hour after intratumoral injection. Static images were obtained at 1 hr, 2 hr, 3 hr and 4 hr after intratumoral injection with Tc-99m pertechnetate and Tc-99m-PA. Target-to-background ratios and retention rates were calculated. Results: Labeling efficiencies of PA, SPA, PA-DTPA and SPA-DTPA were 94.5 ±5.9%, 97.8±3.5% 94.2±3.8%, and 92.5±6.2%, respectively (p>0.05). Percent retention rates (%RR) of PA and PA-DTPA were significantly higher than those of control, however, those of SP-DTPA and SPA became similar to control at 4 and 12 hr, respectively. %RR of pullulan A and pullulan B at 1, 4 and 8 hr is significantly higher than that of control (p<0.051. However, %RR between pullulan A and pullulan B were similar. Conclusion: The ionic strength dependent PD-nanoparticles are retained in the tumor. No difference of %RR according to tumor size was noted. Therapeutic application of PD labelled with beta- or alpha- emitting radionuclides can be expected.

농업문해의 내용영역, 하위요소 및 성취기준 개발

허영준,정철영 한국농·산업교육학회 2008 농업교육과 인적자원개발 Vol.40 No.4

The purpose of this study was to develop for thematic areas, subareas and standards of agricultural literacy. Based on the literature, a definition of the agricultural literacy was derived, and a prototype of thematic Areas, subareas and standards of agricultural literacy was derived. Then, the definition and the prototype were reviewed and corrected by a conference council composed of five experts. As a result, the prototype was converted to a draft which was five thematic areas, twenty susareas and sixty standards. With the Delphi method, the validity of the draft was confirmed by three rounds. Data from each rounds of Delphi surveys were analyzed for means, standard deviations, degree of coincidence and convergence in opinion, agreement rate, stability of responses(t-test), and degree of consensus by SPSS 15.0 version. Whether Delphi survey would continue or not an additional round, was determined by agreement rate(80% or more), CVR(<0.42 in case of 20 experts), and degree of consensus(standard deviations<0.800). The first round of Delphi survey was carried out on twenty expert panels; seven from researchers, six from teachers, and seven from administrators group. The researcher modified the items to which the panels showed mixed responses to open questions, and accommodated the panel's opinion on the validity of thematic areas, subareas and standards. As a result of first round, a modified draft made up of six thematic areas, twenty subareas and fifty-two standards was derived. After the second round of Delphi survey was carried out on the same expert group, a second modified draft composed of six thematic areas, nineteen subareas and fifty-one standards was derived. As a result of the third round of Delphi survey with the second modified draft and modifying the draft on according to opinion of several expert, thematic areas, subareas and standards of agricultural literacy were confirmed. As The results of three rounds of Delphi surveys, agricultural literacy is consisted of six thematic areas, nineteen subareas, and fifty-one standards. Based on the results, several recommendations were suggested. 이 연구는 농업문해의 내용체계를 구성하는 농업문해의 내용영역, 하위요소 및 성취기준을 구명하는데 목적을 두고 수행되었다. 이를 위해 먼저 농업문해의 개념을 정립하는 절차가 필요하였고, 정립된 농업문해의 개념에 기초하여 농업문해의 내용영역, 하위요소 및 성취기준을 구명하는 절차가 밟았다. 농업문해의 내용영역은 개념 정의에 포함된 ‘농업에 관한 기본적인 정보’로서 6개의 영역으로 설정되었으며, 농업문해의 내용요소는 내용영역별로 포함되어야 할 세부 내용요소를 말하고, 성취기준은 일반 국민들이 민주시민으로서 성취하여야 할 농업에 대한 지식과 이해의 목표를 조작적으로 정의한 것이라 할 수 있다. 이 연구의 목적을 달성하기 위하여 문헌연구와 전문가협의 및 델파이조사 등의 연구방법을 적용하여 농업문해의 내용영역, 하위요소 및 성취기준을 최종적으로 개발하였다. 선행연구 및 전문가협의를 통하여 구안된 농업문해의 내용영역, 하위요소 및 성취기준(안)에 대한 타당성을 확보하기 위해 3차에 걸쳐 델파이 조사를 실시하였다. 델파이 조사를 위한 전문가 집단은 농업문해 이론 및 연구, 농업문해 실행, 농업문해 정책 영역으로 구분하여 각각 7명, 6명, 7명 등 총 20명의 해당 분야 전문가들로 구성하였다. 매 라운드별로 각 조사항목에 대한 평균, 표준편차, 긍정률, CVR값, 의견일치도 등을 산출하여 계속 진행해 나갈지를 판단하면서 수행하였다. 그 결과, 농업문해는‘일반 국민들이 농업에 관한 기본 정보를 종합․분석․교환함으로써 일상생활에서 현명한 소비 활동과 국가 정책 결정에 대한 올바른 판단을 가능하게 하는 농업에 대한 기본적인 지식과 이해’로 정의하였다. 농업문해의 내용체계는 6개의 내용영역, 19개의 하위요소, 51개의 성취기준으로 구성되었다. 농업문해의 내용영역은 농업․농촌의 기능과 가치, 농산물의 생산, 농산물의 가공 및 유통, 농식품의 가치와 안전성, 농업과 자연환경, 농업정책 등 6개 영역으로 최종 구명되었다.

In-vitro study on the accuracy of a simple-design CT-guided stent for dental implants

허영준,최보람,허경회,이원진,허민석,이삼선,최순철 대한영상치의학회 2012 Imaging Science in Dentistry Vol.42 No.3

Purpose: An individual surgical stent fabricated from computed tomography (CT) data, called a CT-guided stent, would be useful for accurate installation of implants. The purpose of the present study was to introduce a newly developed CT-guided stent with a simple design and evaluate the accuracy of the stent placement. Materials and Methods: A resin template was fabricated from a hog mandible and a specially designed plastic plate, with 4 metal balls inserted in it for radiographic recognition, was attached to the occlusal surface of the template. With the surgical stent applied, CT images were taken, and virtual implants were placed using software. The spatial positions of the virtually positioned implants were acquired and implant guiding holes were drilled into the surgical stent using a specially designed 5-axis drilling machine. The surgical stent was placed on the mandible and CT images were taken again. The discrepancy between the central axis of the drilled holes on the second CT images and the virtually installed implants on the first CT images was evaluated. Results: The deviation of the entry point and angulation of the central axis in the reference plane were 0.47±0.27 mm, 0.57±0.23 mm, and 0.64±0.16。, 0.57±0.15。, respectively. However, for the two different angulations in each group, the 20。angulation showed a greater error in the deviation of the entry point than did the 10。angulation. Conclusion: The CT-guided template proposed in this study was highly accurate. It could replace existing implant guide systems to reduce costs and effort. Purpose: An individual surgical stent fabricated from computed tomography (CT) data, called a CT-guided stent, would be useful for accurate installation of implants. The purpose of the present study was to introduce a newly developed CT-guided stent with a simple design and evaluate the accuracy of the stent placement. Materials and Methods: A resin template was fabricated from a hog mandible and a specially designed plastic plate, with 4 metal balls inserted in it for radiographic recognition, was attached to the occlusal surface of the template. With the surgical stent applied, CT images were taken, and virtual implants were placed using software. The spatial positions of the virtually positioned implants were acquired and implant guiding holes were drilled into the surgical stent using a specially designed 5-axis drilling machine. The surgical stent was placed on the mandible and CT images were taken again. The discrepancy between the central axis of the drilled holes on the second CT images and the virtually installed implants on the first CT images was evaluated. Results: The deviation of the entry point and angulation of the central axis in the reference plane were 0.47±0.27 mm, 0.57±0.23 mm, and 0.64±0.16。, 0.57±0.15。, respectively. However, for the two different angulations in each group, the 20。angulation showed a greater error in the deviation of the entry point than did the 10。angulation. Conclusion: The CT-guided template proposed in this study was highly accurate. It could replace existing implant guide systems to reduce costs and effort.

CEREC 3D System의 이해

허영준 대한치과재료학회 2008 대한치과기재학회 학술대회 Vol.2008 No.11

UBM 스퍼터링을 이용한 불용성 전극용 Ta 박막의 증착 및 특성

허영준,손영호,정우철,정재인,고광락 한국진공학회 2001 한국진공학회 학술발표회초록집 Vol.- No.-

LED 모듈 표준 표시사항의 경제적인 평가를 위한 단일 핀 방열 블록의 냉각성능 예측

허영준,송명호,Huh, Young-Joon,Song, Myung-Ho 한국태양에너지학회 2015 한국태양에너지학회 논문집 Vol.35 No.3

LED has received intensive research attention due to its long life, high efficacy, fast response and wide colour availability, and has secured extensive application areas. However, LED chips within the modules convert only fraction of electric energy into light, and majority of supplied energy needs to be dissipated as heat, which challenges in the performance and life of the LED modules. IEC 62717 specifies the performance requirements for LED modules together with the test methods and conditions. The present study examined the influence of different design parameters on performance temperature through series of experiments and numerical simulations. The economic means to change the module performance temperature during the measurement of mandatory markings were suggested based on predicted cooling performances.

미국 700MHz 주파수 경매결과

허영준,전수연 정보통신정책연구원 2008 정보통신정책 Vol.20 No.6

영국의 이동통신 네트워크 커버리지 현황

허영준 정보통신정책연구원 2008 정보통신정책 Vol.20 No.11

DACUM기법을 활용한 경기도소방학교 교육훈련과정 개발

허영준 한국농·산업교육학회 2010 농업교육과 인적자원개발 Vol.42 No.4

The purpose of this study was to suggest the education and training program for fire-fighter by job analysis, curriculum development, and comparison between present curriculum and new-developed curriculum. First, job classification of Gyeonggi provincial fire-fighter was consisted of five jobs - adminstration, prevention, correspondence, rescue, and emergency - by three times discussions of expert panels. and Job analysis and curriculum development were performed by the DACUM panels who consisted of five subject-matter experts and one educational expert on each field. DACUM committee was held four times, orientation about DACUM technique was given to panels in first meeting. Job classification of Gyeonggi provincial fire-fighter was consisted of five jobs; (1)adminstration job was consisted of eleven duties and forty-seven tasks, (2)prevention job was eight duties and sixty-nine tasks, (3)correspondence job was twelve duties and forty-two tasks, (4)rescue job was two duties and forty-six tasks, and (5)emergency job was two duties and forty-three tasks. Considering importance, difficulty, and frequency of each task, if it was high order priority of education and training, key tasks was chose; (1)adminstration job was thirty-one tasks, (2)prevention job was forty-seven tasks, (3)correspondence job was twenty-four tasks, (4)rescue job was thirty-nine tasks, and (5)emergency job was forty-one tasks. Then task elements, concerned knowledge, skills, attitude and tools wre derived from each task, and job analysis step was completed by compiling key tasks vs. knowledge, skills, attitude, and tools matrix. Considering time and teaching method for understanding and proficiency of them, education and training type and course type were determined by discussion of 5 panels. Then, courses were named, and subjects of each course were derived by reviewing synthetically these required knowledge, skills, attitude and tools upon three principles; continuity, sequence, integration, and curriculum development step was accomplished by making course profile and subject profile. These profiles were consisted of title, goal, contents, time, target, and tools and materials. Finally, it was proposed that it is very necessary of reconstruction of the education and training system for fire-fighter by comparing present curriculum and new-developed curriculum. Several suggestions for reconstruction of education and training system were proposed; application of new-developed curriculum, improvement of education and training delivering system, introduction of always-learning system, continuous research on fire-fighter job. 이 연구는 경기도소방학교의 교육훈련과정을 개발하는 데 그 목적이 있으며, 이를 위해 직무분석, 신교육과정 개발, 현행 교육과정과의 비교 분석 등의 절차를 거쳤다. 먼저, 경기도 소방공무원의 직무체계에 대한 전문가협의를 통해 행정, 예방, 대응, 구조, 구급의 5개 분야로 설정하였다. 각 직무분야별로 5명의 내용전문가와 1명의 교육훈련전문가로 구성된 DACUM 패널에 직무분석 및 교육과정 개발을 수행하였다. DACUM 전문가협의회는 총 4회에 걸쳐 개최되었는데, 1차 협의회에서는 DACUM기법에 대한 이해를 높이기 위하여 사전교육을 실시하였다. 경기도소방공무원의 직무체계를 살펴보면, 행정분야는 11개 책무와 47개 작업, 예방분야는 8개 책무와 69개 작업, 대응분야는 12개 책무와 49개 작업, 구조분야는 2개 책무와 46개 작업, 구급분야는 2개 책무와 43개 작업으로 각각 분석되었다. 책무별로 작업을 도출하여 중요도, 난이도, 빈도를 기준으로 교육훈련 우선순위가 높은 작업을 핵심작업으로 선정하였는데, 행정분야는 31개, 예방분야는 47개, 대응분야는 24개, 구조분야는 39개, 구급분야는 41개로 최종 확정되었다. 각 핵심작업에 대한 작업요소, 관련 지식, 기능, 태도 및 장비를 도출하여, 핵심작업/지식․기능․장비 매트릭스를 작성함으로써 직무분석 단계를 완료하였다. 교육과정 개발 절차는 핵심작업/지식․기능․장비 매트릭스에 기초하여 시작되었다. 도출된 지식, 기능 및 장비에 대하여 이해 및 숙달에 소요되는 시간과 방법 등을 고려하여 어떤 교육훈련형태(학교교육(집합교육), 직장교육, 직무보조자료, 사이버교육)가 적합한지, 그리고 어떤 코스형태(기본교육, 전문교육, 현장교육)로 운영되어야 하는지를 내용전문가(분임별 5인)의 의견 합의를 통해 결정하였다. 코스형태별로 필요한 코스명을 도출하였고, 코스명을 기초로 하여 필요한 지식, 기능 및 장비를 종합적으로 검토하여 계속성, 계열성, 통합성 등의 교육내용 조직 원칙에 따라 교과목을 도출하였다. 각 교과목별로 교과목표, 교육내용, 교육시간, 교육 대상, 교육방법, 교육기자재 등을 도출하여 교과목 프로파일을 작성하였고, 교과목 프로파일에 기초하여 코스 프로파일을 작성함으로써 교육과정 개발 단계를 완료하였다. 마지막으로 이 연구에서 도출된 교육과정(안)과 현행 교육과정을 비교함으로써 향후 경기도 소방학교 교육훈련체계 개편의 필요성을 제기하였다. 경기도 소방학교의 교육훈련체계 개편을 위해, 신 교육과정(안)의 활용, 교육훈련방식의 개선, 상시학습제도의 도입, 소방공무원의 직무에 대한 지속적인 연구 등을 제안하였다.