Special Issue of Professor Kiehwa Lee`s Retirement: Geophysical Environments of the Korean Peninsula : Articles ; Geoelectrical Structure of the Kyongsang Basin from Magnetotelluric Sounding

( Choon Ki Lee ),( Heui Soon Lee ),( Byung Doo Kwon ),( In Ky Cho ),( Seok Hoon Oh ),( Yoon Ho Song ),( Tae Jong Lee ) 대한지구물리학회 2006 지구물리 Vol.9 No.3

가토 외고정 모델을 이용한 치밀체형 세라믹스의 골결합능 평가

이재협,이동호,이재학,공현식,안영준,류현승,서준혁,홍국선,김환,장봉순,이춘기 대한정형외과연구학회 2003 대한정형외과연구학회지 Vol.6 No.2

Voxel머리팬텀 제작 및 붕소중성자포획요법 선량계산에의 응용

이춘식,이춘익,이재기 대한방사선 방어학회 2001 방사선방어학회지 Vol.26 No.2

해부학적으로 단순한 수학적인형팬텀의 한계를 극복하기 위한 voxel머리팬텀을 제작하고 BNCT(Boron Neutron Capture Therapy) 시행 시 선량분포를 계산하였다. 일반목적 몬테칼로 코드인 MCNP4B의 반복구조 알고리즘을 이용하여 voxel몬테칼로 계산체계를 수립하였고 두 가지 물질로 구성된 예시적 voxel팬텀과 기하체조합팬텀의 계산값 비교를 통해 계산체계를 검증하였다. 미국 NLM(National Library of Medicine)에서 제공하는 VHP man 인체단층사진에 대한 분할 및 색인작업을 통해 voxel머리팬텀을 제작하여 AP 및 PA 방향에서 입사하는 넓고 평행한 광자 및 중성자빔에 대한 선량값을 MIRD팬텀의 계산값과 비교한 결과 중성자빔 AP방향조사 시 MIRD팬텀에서는 볼 수 없는 안구로 인한 중성자 감쇠현상을 확인할 수 있었다. 3차원 정밀계산이 필요한 BNCT 시술시 선량분포계산을 위해 뇌 중앙에 직경 5cm의 구형 뇌종양 체적을 정의하고 뇌와 종양의 붕소 함량을 조정하여 10keV 및 40keV 상부입사 중성자에 의한 장기별 흡수선량을 계산한 결과 종양에 30㎍/g, 정상세포에 3㎍/g 의 붕소를 주입한 경우 붕소함량이 없을 때에 비해 2배 가량 큰 선량을 보였다. 본 연구를 통해 voxel몬테칼로기법을 이용한 선량평가체계를 수립하였고 정밀한 선량계산을 필요로 하는 치료방사선분야 선량계산에 실제 인체에 가까운 voxel팬텀의 응용가능성을 제시하였다. Voxel head phantom for overcoming the limitation of mathematical phantom in depicting anatomical details was constructed and example dose calculation for BNCT was performed. The repeated structure algorithm of the general purpose Monte Carlo code, MCNP4B was applied for voxel Monte Carlo calculation. Simple binary voxel phantom and combinatorial geometry phantom composed of two materials were constructed for validating the voxel Monte Carlo calculation system. The tomographic images of VHP man provided by NLM(National Library of Medicine) were segmented and indexed to construct voxel head phantom. Comparison of doses for broad parallel gamma and neutron beams in AP and PA directions showed decrease of brain dose due to the attenuation of neutron in eye balls in case of voxel head phantom. The spherical tumor volume with diameter, 5cm was defined in the center of brain for BNCT dose calculation for downward neutron beam of 10keV and 40keV, the tumor dose is about doubled when boron concentration ratio between the tumor to the normal tissue is 30㎍/g to 3㎍/g. This study established the voxel Monte Carlo calculation system and suggested the feasibility of precise dose calculation in therapeutic radiology.

最近 3年間 本敎室에서 經驗한 腫瘍 253例에 對한 臨床病理組織學的 考察

李揆鶴,高永春,李廷鎭,朴鍾雲,李鍾元,林鍾福,林春悅,朴順道 최신의학사 1964 最新醫學 Vol.7 No.4

The Knight’s Tale and The Miller’s Tale as One Tale

Lee,Dong-Choon 신영어영문학회 2011 신영어영문학 Vol.49 No.-

Lee, Dong-Choon. The Knight’s Tale and The Miller’s Tale as One Tale. The New Studies of English Language & Literature 49 (2011): 103-131. The first two tales-the Knight’s Tale and the Miller’s Tale-of the Canterbury Tales are the representative examples that reflect not only the narrative technique of the “juxtaposition of opposites,” but also Chaucer’s narrative tendencies. The special poetic achievements (and limitations) of each are seen most clearly when the two tales are read together, one in the light of the other, as their juxtaposition invites. The Knight’s Tale and the Miller’s Tale, when read together, are the representative examples which tell what Chaucer attempts to show through his narrative technique of the juxtaposition of opposites and what attitude he expects from a reader. Chaucer does not mechanically indoctrinate an unique view of the world to the readers. He, avoiding his authorial stance on a certain limited view embodied in each tale, forces the specific views of the narrative onto the reader. It is through the juxtaposition between the completely different two tales in such things as tale-teller, plot, character, language, and the narrative voice that Chaucer creates the multiplicity of voice and the plurality of theme, and he trains a reader to grope for meaning from various sides. (Daegu University)

Phosphorus Removal in Pilot Plant Using Biofilm Filter Process from Farm Wastewater

Shin, Sung-Euy,Choi, Du-Bok,Lee, Choon-Boem,Cha, Wol-Suk The Korean Society for Biotechnology and Bioengine 2006 Biotechnology and Bioprocess Engineering Vol.11 No.4

Various environmental conditions affecting total phosphorus removal from farm wastewater in a biofilm filter process were investigated using loess balls and Chromobacterium LEE-38 at a pilot plant. When Chromobacterium LEE-38 was used, the removal efficiency of total phosphorous was approximately 10- or 5-fold higher than that of Acinetobacter CHA-2-14 or Acinetobacter CHA-4-5, respectively. When a loess ball of $11{\sim}14mm$ manufactured at a $960^{\circ}C$ calcining temperature was used, the removal efficiency of total phosphorous was 90.0%. When 70% of the volume fraction was used, the maximum efficiency of total phosphorus removal was 93.1%. Notably, when the initial pH was in the range of 6.0 to 8.0, the maximum removal efficiency of total phosphorus was obtained after 30 days. When the operating temperature was in the range of 30 to $55^{\circ}C$, the maximum removal efficiencies of total phosphorus, 95.6 to 94.6%, were obtained. On the other hand, at operating temperatures below $20^{\circ}C$ or above $40^{\circ}C$, the removal efficiency of total phosphorous decreased. Among the various processes, biofilm filter process A gave the highest removal efficiency of 96.4%. Pilot tests of total phosphorus removal using farm wastewater from the biofilm filter process A were carried out for 60 days under optimal conditions. When Acinetobacter sp. Lee-11 was used, the average removal efficiency in the p-adsorption area was only 32.5%, and the removal efficiencies of chemical oxygen demand (COD) and biological oxygen demand (BOD) were 56.7 and 62.5%, respectively. On the other hand, when Chromobacterium LEE-38 was used, the average removal efficiency was 95.1%, and the removal efficiencies of COD and BOD were 91.3 and 93.2%, respectively.

Phosphorus Removal in Pilot Plant Using Biofilm Filter Process from Farm Wastewater

차월석,Sung-Euy Shin,DuBok Choi,Choon-Boem Lee 한국생물공학회 2006 Biotechnology and Bioprocess Engineering Vol.11 No.4

Various environmental conditions affecting total phosphorus removal from farm wastewater in a biofilm filter process were investigated using loess balls and Chromobacterium LEE-38 at a pilot plant. When Chromobacterium LEE-38 was used, the removal efficiency of total phosphorous was approximately 10- or 5-fold higher than that of Acinetobacter CHA-2-14 or Acinetobacter CHA-4-5, respectively. When a loess ball of 11~14 mm manufactured at a 960°C calcining temperature was used, the removal efficiency of total phosphorous was 90.0%. When 70% of the volume fraction was used, the maximum efficiency of total phosphorus removal was 93.1%. Notably, when the initial pH was in the range of 6.0 to 8.0, the maximum removal efficiency of total phosphorus was obtained after 30 days. When the operating temperature was in the range of 30 to 55°C, the maximum removal efficiencies of total phosphorus, 95.6 to 94.6%, were obtained. On the other hand, at operating temperatures below 20°C or above 40°C, the removal efficiency of total phosphorous decreased. Among the various processes, biofilm filter process A gave the highest removal efficiency of 96.4%. Pilot tests of total phosphorus removal using farm wastewater from the biofilm filter process A were carried out for 60 days under optimal conditions. When Acinetobacter sp. Lee-11 was used, the average removal efficiency in the p-adsorption area was only 32.5%, and the removal efficiencies of chemical oxygen demand (COD) and biological oxygen demand (BOD) were 56.7 and 62.5%, respectively. On the other hand, when Chromobacterium LEE-38 was used, the average removal efficiency was 95.1%, and the removal efficiencies of COD and BOD were 91.3 and 93.2%, respectively.

단일방향 섬유 복합재료 내의 초음파 전파 및 산란 현상의 해석과 시뮬레이션

이춘재,임현준 한국비파괴검사학회 2001 한국비파괴검사학회지 Vol.21 No.3

복합재료의 초음파검사는 매질의 탄성이방성으로 인해 빔스큐(beam skew)현상 등이 발생하기 때문에 등방성 재료의 검사에 비해 훨씬 어렵다. 그 동안의 많은 연구의 결과로서 이방성 재료 내 탄성파의 전파 현상에 대한 해석해법이 정립되어 있으나, 그 해석해가 매우 복잡하여 실제 문제의 해를 구하기 위해서는 수치적인 방법에 의존하여야 하는 경우가 많다. 본 연구에서는 횡등방 이방성(transversely isotropic)으로 가정할 수 있는 단일방향 섬유 복합재료 내점원에 의한 초음파 전파의 해석해를 먼저 구하고, 이러한 복합재료를 질량-스프링 모델로 모델링하여 해석해에 상응하는 수치해를 구하였다. 그 결과, 초음파의 전파에 대한 수치해와 해석해가 매우 잘 일치하는 것을 확인하였다. 동일한 수치해법을 사용하여 초음파가 복합재료의 자유표면에서 반사되는 현상과 균열에 의해 산란되는 현상에 대한 수치해도 구하였으며 그 결과를 파동역학의 관점에서 고찰하였다. 본 연구에서 그 유효성이 확인된 수치 모델은 복합재료의 초음파검사를 시뮬레이션 함에 있어 매우 유용하게 사용될 수 있을 것이다. Ultrasonic testing of composite materials is much more difficult than that of isotropic materials, because of the beam skew phenomenon caused by their elastic anisotropy. An established analytical method exists for elastic wave propagation in anisotropic media as a result of previous research efforts. Yet, due to the complexity of the analytical method, solution of real problems must resort to the numerical method. In this work, analytical solutions have first been obtained for the wavefield due to a point source in a unidirectional fiber-reinforced composite, which may be modeled as transversely isotropic. Then, the corresponding numerical solutions have been obtained using the mass-spring lattice model(MSLM). The two solutions have agreed well with each other. Other problems such as reflection from free boundaries and scattering from cracks have also been solved numerically, and the results have been investigated from the viewpoint of wave mechanics. The numerical model whose validity has been confirmed by this work will be of great use in simulating ultrasonic testing of composite materials.

조선시대 찬장과 찬탁에 대한 조형적 특성에 관한 연구

이춘섭 대구대학교 인문과학연구소 1996 人文科學硏究 Vol.15 No.-

Automatic Bottle Air Rinser 개발에 관한 연구

이춘만,김대성,김현진 한국공작기계학회 2004 한국공작기계학회 춘계학술대회논문집 Vol.2004 No.-

This study has been focused on the development of automatic bottle air rinser. It is designed to rinse clean empty bottles prior to filling. The bottles are automatically indexed beneath an air nozzle that has both a clean airjet and vacuum source. The bottle is first given a burst of clean air to loosen any particles from the wall of the bottle. A vacuum sequence follows which removes all particulates into a self contained filter unit. In order to the provide the desired function, analysis is carried out by FEM simulation using FLUENT and CATIA software. The final results of analysis are applied to the design of automatic bottle rinser and the machine is successfully developed.