DO와 ORP를 이용한 축산폐수처리 SBR운전 제어

전병희 ( Byong Hee Jun ),김도환 ( Do Hwan Kim ),최은희 ( Eun Hee Choi ),김성신 ( Sung Shin Kim ),김창원 ( Chang Won Kim ),배현 ( Hyeon Bae ) 한국물환경학회 2002 한국물환경학회지 Vol.18 No.5

A pilot scale SBR (working volume, 20㎥) treating piggery wastewater was operated with real wastewater. The operation mode of intermittent feeding of raw water and sub-cycle with repeating anoxic-aeration conditions were adapted to avoid the high-strength nitrogen inhibition. In sub-cycle, aeration time for nitrification was tried to be controled with ORP and/or DO meter. The characteristics of control was somewhat different between ORP and DO. DO showed potential ability to detect complete ammonia oxidation point by the first order differential values or absolute value. Especially, DO was proved to be useful for high loading rates. ORP indicated the ending point of nitrification by the plateau appearing after bending point. Because ORP can be utilized as a diagnosis tool by its good sensitivity for the microbial condition in reactor, the simultaneous application of DO and ORP was recommended for the stable control of SBR.

가상시나리오를 활용한 의과대학 학사편입학 지원자의 윤리적 의사결정능력

김도환,김은정,황진영,신좌섭,이승희,Kim, Do-Hwan,Kim, Eun Jeong,Hwang, Jinyoung,Shin, Jwa-Seop,Lee, Seunghee 연세대학교 의과대학 2016 의학교육논단 Vol.18 No.2

Assessment tools for non-academic qualities such as ethics frequently employ hypothetical scenarios to lay out a contextual framework underlying the corresponding criteria of assessment. Due to the context-specific nature of the assessment criteria, details of the scenarios become very important in obtaining accurate results. This study aims to explore how medical school applicants differ in ethical decision making depending on the types of ethical dilemma scenarios, and how they correlate with academic achievements after admission. In 2014, all 82 applicants invited for an admission interview for a graduate-entry program were asked to complete a questionnaire comprised of 13 hypothetical scenarios. There were three domains (unethical business decisions, unethical academic decisions, and sexual quid pro quos) and participants were made to choose between the profitable-but-unethical choice or the unprofitable-but-ethical choice, using a four-point Likert-type scale. On average, tendencies toward unethical decisions were lowest for sexual favors ($1.34{\pm}0.46$), and highest for gaining academic advantages ($2.22{\pm}0.56$). Unethical decisions for academic advantages and sexual benefits showed significant correlation respectively with the female gender and those who graduated from overseas universities. In addition, the propensity for choosing unethical academic decisions was significantly correlated with high academic achievements in medical school (r=0.396). Not only does this study demonstrate that different levels of ethical decision making depend on the scenarios, but also those differences may be a determinant factor in subsequent academic performances in medical school. In conclusion, given the possible influence of the details of the hypothetical scenarios to the applicant's responses, careful consideration must be given during their development.

의과대학 선택교육과정의 운영절차와 만족도 평가

김도환,최영휴,한상윤,신좌섭,이승희,Kim, Do-Hwan,Choi, Young-Hyu,Han, Sang Yun,Shin, Jwa-Seop,Lee, Seunghee 연세대학교 의과대학 2017 의학교육논단 Vol.19 No.2

The necessity of embracing selective courses in medical curriculum is increasing due to the expansion of medical knowledge and changes in the health care environment. In contrast to the abundant evidence regarding elective or selective courses during the clinical phase, articles focusing on the preclinical period are relatively scarce. This study aims to explore the development, implementation, and evaluation of newly-adopted selective courses in the first-year medical curriculum in a medical school which recently underwent a major curricular revision. First of all, the Curriculum Committee established goals and operating principles of the courses, and then the committee encouraged all participating professors to attend a related faculty development workshop after finalizing the list of courses. A survey was conducted at the end of each course for evaluation. Of the 36 courses opened in 2016, the overall satisfaction of students was $4.98{\pm}1.06$ (out of 6) and showed a strong correlation with students' previous expectations, reasoning- and participation-oriented teaching, and outcome of the courses including increased motivation. In the open-ended responses, students and professors described not only intended outcomes such as acquisition of medical knowledge and increased interest in new topics, but also unintended outcomes including positive impression for selective courses and even high satisfaction and rewarding experiences, especially from the teachers' perspective. Although long-term outcomes remain to be seen, the results of this study show the feasibility and impact of selective courses and will contribute to effective implementation in other medical schools.

Nitric Oxide에 의해 유발된 C6 glial 세포독성(細胞毒性)에 대한 사물탕(四物湯)의 방어효과(防禦效果)

김도환,김승모,조한국,차용석,허윤,조광호,문병순,Kim, Do-Hwan,Kim, Seung-Mo,Cho, Han-Gook,Cha, Yong-Seok,Heo, Yun,Cho, Kwang-Ho,Moon, Byung-Soon 대한한방내과학회 2000 大韓韓方內科學會誌 Vol.21 No.4

The water extracts of Samul-tang(SMT) has been used for treatment of ischemic brain damage in Oriental traditional medicine. However, little is known about the mechanism by which the water extracts of SMT rescues brain cells from ischemic damages. To elucidate the protective mechanism on ischemic induced cytotoxicity, I investigate the regulation of LPS and PMA induced iNOS expression in C6 glial cells. LPS and PMA treatment for 72 h in C6 glial cells markedly induce nitric oxide(NO), but treatment of the cells with the water extracts of SMT decrease. dose dependently nitrite formation. In addition, LPS and PMA treatment for 72 h induce severe cell death and LDH release in C6 glial cells. However treatment of the cells with the water extracts of SMT dose not induce significant changes compare to control cells. Furthermore, the protective effects of the water extracts of SMT is mimicked by treatment of $N^{G}MMA$, a specific inhibitor of NOS. LPS and PMA induced iNOS activation in C6 glial cells cause chromosomal condensation and fragmentation of nuclei by caspase activation. The treatment of the cells with the water extracts of SMT may suppress apoptosis via caspase inhibition by regulation of iNOS expression. Taken together, I suggest that the protective effects of the water extracts of SMT against ischemic brain damages may be mediated by regulation of iNOS during ischemic condition.

스마트 미터 및 센서 네트워크 기반 상수관망 운영관리 최적화

김도환,최두용,김주환,Kim, Do-Hwan,Choe, Du-Yong,Kim, Ju-Hwan 한국수자원학회 2014 물과 미래(한국수자원학회지) Vol.47 No.5

건축구조용 고성능 강재 HSA800의 효율적 사용을 위한 초고층 건물의 적용성 평가

김도환,김주우,이동우,양재근,이명재,Kim, Do Hwan,Kim, Joo Woo,Lee, Dong Woo,Yang, Jae Guen,Lee, Myung Jae 한국강구조학회 2014 韓國鋼構造學會 論文集 Vol.26 No.5

최근 건축물의 초고층화, 대형화 및 장경간화에 따른 요구 성능의 증대에 따라 강재 및 콘크리트 등의 구조재료가 지니는 재료강도 및 사용성 등을 향상시키고자 하는 노력이 지속적으로 이루어지고 있다. 본 연구에서는 개발된 건축구조용 고성능 강재의 기계적, 화학적 소재 특성을 평가하고, 실제 Project를 대상으로 대안설계를 수행하여 고강도 강재의 경제성을 평가하였다. HSA800은 고강도와 좋은 용접성을 갖추기 위해 TMCP 방식으로 제조되었으며, 기계적, 화학적 성질 모두 KS규격을 만족하였다. 또한 HSA800의 고층건물의 적용성 및 경제성 평가를 위해 SM490강재 모델과 사용성에 초점을 두고 비교 평가를 수행하였다. 그 결과 SM490대비 약 30% 물량절감이 가능하였다. HSA800의 사용은 추후 건축구조의 제작, 시공 뿐만아니라 공사비 절감에도 기여할 것으로 기대되어진다. As building height and span is getting taller and longer, the researches to increase material's strength and serviceability are continuously performed. This study evaluated mechanical and chemical properties of newly developed high-strength steel (HSS) for building structures, namely HSA800 and verified cost-effectiveness and applicability of HSS for a tall building by comparing the analysis results of normal strength steel (SM490) model. HSA800 was manufactured by TMCP to have a good weldability in spite of HSS and satisfied Korean Industrial Standards (KS). The analysis results for evaluating cost-effectiveness show that total steel quantity could be saved approximately 30% when using HSS compared to SM490. It is expected that HSA800 will contribute to enhance constructability of building.

신규 입체프레임을 이용한 도로용 터널 내부 유지관리 시공기술 개발

김도환,노필성,유진오,이동규,Kim, Do Hwan,Roh, Phil Sung,Yoo, Jin Oh,Lee, Dong Kyu 한국구조물진단유지관리공학회 2014 한국구조물진단유지관리공학회지 Vol.18 No.4

The research regarding the energy storage device which applies the carbon nanotube

김도환,강순덕,Kim, Do-Hwan,Kang, Soon-Duk Korea Institute of Information Technology and Inno 2007 情報學硏究 Vol.10 No.2

The multiple-ability which the structure and the physical properties which the carbon or scull tube are unique show the applicability is superior in the plane indication element which is an indispensability of information communications apparatus, the stubbornness memory element, 2nd change of air and the rough copy dosage [khay] plaque seater, the hydrogen store material and the chemical sensor back and it has the possibility which will pass over the limit which the element of existing has. from the present paper it compared in the steel and only 10 the boat it did and it analyzed against an energy storage space voluntary application and developmental apply the carbon or scull tube trend in order about under researching the effective energy storage element it could be appeared, the technique of the strong carbon nano tube. 1. The hazard which embodies the energy storage element which uses the carbon or scull tube it follows in the function which stands and CNT of the structure which is various is necessary. 2. CNT fabrications of each one must precede possible not only must be each Cabinet conference circumstances quality gain and loss. 3. The structural control of syntheses, length controls, diameter controls and the metal - CNT junction control backs of quality CNT must precede. Applies the hereafter carbon or the scull tube in the various element with the primary preceding base technique for the structural plan technique of the carbon or scull tube to be certainly established, it does, secondarily the various element functional control technique which uses the carbon or scull tube is researched and will do.

나노 임프린트 기술을 이용한 폴리머 도파로 기반의 브래그 격자형 파장 가변 필터

김도환,진원준,이상신,안세원,이기동,Kim, Do-Hwan,Chin, Won-Jun,Lee, Sang-Shin,Ahn, Seh-Won,Lee, Ki-Dong 한국광학회 2006 한국광학회지 Vol.17 No.1

A tunable wavelength filter was proposed and demonstrated by using the UV nanoimprint technique. It consists of a Bragg grating in polymer waveguides and a heating electrode. The manufacturing of the grating was substantially simplified with the introduction of a smart imprint stamp containing a waveguide pattern integrated with the grating pattern. The center wavelength of the filter was successfully tuned by taking advantage of the thermooptic effect in polymers, which was induced by supplying electrical power to the electrode. For the fabricated device, a transmission dip of ${\~}$15 dB and a 3-dB bandwidth of 0.8 nm were obtained at the Bragg wavelength of ${\~}$l560 nm. The achieved thermooptic tuning efficiency was ${\~}$0.28 nm/mW, while the center wavelength was shifted from 1560 nm to 1558 nm with the electrical power consumption of 7 mW. 본 논문에서는 UV 나노임프린트 기술을 이용하여 파장가변 필터를 제안하고 구현하였다. 제안된 소자는 폴리머 도파로 기반의 브래그 격자와 열 광학효과를 위한 히팅용 전극으로 구성되어 있다. 도파로 패턴과 브래그 격자 패턴이 결합된 임프린트용 스탬프를 이용하여 브래그 격자를 구현하였다. 전극에 전력을 인가하여 폴리머의 열 광학효과를 통하여 필터의 중심파장을 효과적으로 이동시킬 수 있었다. 제작된 소자는 브래그 파장대역인 1560 nm 에서 대역저지 소멸비가 15 dB이며, 대역폭이 0.8 nm였다. 또한 소비전력이 7 mW일 때 중심파장은 1560 nm에서 1558 nm로 이동되었다. 이 때 열 광학효과 파장가변 특성이 약 0.28 nm/mW 였다.

나노 임프린트 기술을 이용한 폴리머 링 광공진기

김도환,임정규,이상신,안세원,이기동,Kim, Do-Hwan,Im, Jung-Gyu,Lee, Sang-Shin,Ahn, Seh-Won,Lee, Ki-Dong 한국광학회 2005 한국광학회지 Vol.16 No.4

A polymer optical microring resonator, which is laterally coupled to a straight bus waveguide, has been proposed and demonstrated using a nanoimprint technique. The propagation loss of the ring waveguide and the optical power coupling between the ring and bus waveguides was calculated by using a beam propagation method, then the dependence of the device performance on them was investigated using a transfer matrix method. We have especially introduced an imprint stamp incorporating a smoothing buffer layer made of a silicon nitride thin film. This layer played an efficient role in improving the sidewall roughness of the waveguide pattern engraved on the stamp and thus reducing the scattering loss. As a result the overall Q factor of the resonator was greatly increased. Also it reduced the gap between the ring and bus waveguides effectively to enhance the coupling between them, without relying on the direct writing method based on an e-beam writer. As for the achieved device performance at the wavelength of 1550 nm, the quality factor, the extinction ratio, and the free spectral range were ~103800, ~11 dB, and 1.16 m, respectively. 본 논문에서는 나노 임프린트 기술을 이용한 폴리머 링 광공진기를 제안하고 구현하였다. 공진기 역할을 하는 링 도파로에서의 전파손실과 링 및 버스 도파로 간의 광파워 결합계수를 빔전파방법을 도입하여 계산하였으며, 또한 전달 매트릭스 방법을 도입하여 이들이 소자에 미치는 영향을 분석하고 소자를 설계하였다. 특히, smoothing buffor layer를 갖는 임프린트용 스탬프를 도입하여 다음과 같은 성과를 얻을 수 있었다. 먼저 식각공정으로 얻어진 스탬프 상의 도파로 패턴의 측면 거칠기를 링 도파로의 산란손실을 개선함으로써 Q값을 획기적으로 향상시켰다. 또한, 결합영역에서 버스와 링 도파로 간의 간격을 기존 lithography 공정에서는 불가능하였던 $0.2{\mu}m$정도까지 효과적으로 줄이고 제어함으로써 링과 도파로 간의 광파워 결합을 정밀하게 조절할 수 있게 되었다. 제작된 소자의 성능을 살펴보면, 링 반경이 $200{\mu}m$인 경우에 대해 1550 nm 파장 대역에서 Q값은 ~103800이고, 소멸비는 ~11 dB, free spectral range는 1.16 nm였다.