저전압 / 저전력 고성능 배럴 쉬프터의 설계 ( Design of Low Voltage / Low Power High Performance Barrel Shifter )

조훈식,손일헌 대한전자공학회 1998 대한전자공학회 학술대회 Vol.1998 No.11

래버린스 위어를 이용한 침사지 내 침전효율 개선

조훈식(Cho Hun Sik),여창건(Yeo Chang Geon),임장혁(Im Janghyuk),이승오(Lee Seung Oh) 대한토목학회 2012 대한토목학회논문집 B Vol.32 No.3B

In this study, we proposed modified settling basins transformed by substituting the downstream sill for low head weirs such as generic labyrinth weir and inclined crest labyrinth weir worked as internal baffles. Laboratory experiments were carried out to understand hydraulic characteristics inside of the settling basin to improve the efficiency of sedimentation rate. For a quantitative analysis, we suggested the headwater ratio(Hl/P), the magnification ratio(L/W) and the inflow rate per total crest length(qL) as primary analysis indexes for sedimentation efficiency. Six different types of settling basin were used for lab-scaled pilot tests by distinguishing with internal structures. Based on results, the variation of headwater ratio with the change of magnification ratio would highly affect the deposition efficiency(%) and it was improved under specific condition that repeating arrange number(N) of labyrinth weir was between 2 and 4. Also, the regression analysis showed that initial condition and shape for improving sedimentation efficiency were plotted on the graph for both qL≥3.5 ㎠/s and L/W≤3.5. It would be expected that the geometrically optimized labyrinth settling basin could be designed with proper deposition efficiency for inflow rates of influent and required area of settling basin utilizing the proposed analysis index in this study. 본 연구에서는 기존의 침사지 내부 수공구조물(격벽)로 사용되고 있는 둔턱을 대체하여 일반형 사다리꼴 래버린스 위어(generic labyrinth weir)와 변형된 형태인 경사형 마루 래버린스 위어(inclined crest labyrinth weir)를 제시하였으며, 래버린스 위어 적용시 발생하는 수리학적 흐름특성을 이용하여 침사지에서 침전율을 개선하고자 하였다. 본 연구에서는 전수두비(headwater ratio) Hl/P와 확폭비(magnification ratio) L/W, 그리고 총 마루길이 당 유입유량 qL을 침전효율의 주요 분석지표로 제시하였으며, 기존의 침사지 형상과 래버린스 위어를 적용한 래버린스 침사지 형상을 제작하여 실험을 수행하였다. 실험결과 래버린스 위어를 적용한 침사지는 확폭비 변화에 따른 전수두비의 변동이 침전효율(%)에 크게 영향을 미치는 것으로 분석되었으며, 래버린스 위어 반복배열수(N)가 2~4개 일 때 침전효율이 개선되는 것으로 분석되었다. 또한 회기분석을 통해 침전효율이 개선되는 유입조건 및 형상은 총 마루길이 당 유입유량이 qL≥3.5 ㎠/s인 조건과 확폭비가 L/W≤3.5 인 경우로 나타났으며, 이러한 침전효율이 개선되는 구간을 도표상으로 표현 및 분석하였다. 본 연구에서 제시한 분석지표를 통해 오탁수 유입량 및 침사지 소요면적 등 설계조건에 따른 적합한 침전효율을 갖는 구조적으로 최적화된 래버린스 침사지의 기초 설계에 활용될 수 있을 것이다.

제미니형 계면활성제

이동탁,김혁,조훈식 ( Dong Tak Lee,Hyuk Kim,Hoon Sik Cho ) 한국유화학회 1994 한국응용과학기술학회지 Vol.11 No.1

Mainstream smoke level of harmful substances in korean domestic cigarette brands

최현덕,홍석호,조훈식,김형경,이진희,윤순병,허석,박형준 한국분석과학회 2018 분석과학 Vol.31 No.1

After signing the WHO FCTC in 2003, South Korea ratified the FCTC in 2005. This study was conducted to provide data on toxic constituents that can be used as useful information for the level of exposure to Korean smokers. Emissions data from five brands of cigarettes were tested under the ISO and “Canadian Intense (HCI)” smoking regimes, respectively. We conducted an analysis of 25 compounds containing nicotine, tar, carbonyls, phenolics, volatile organic compounds (VOCs), and semi-VOC cigarette smoke. Tar and nicotine showed levels of 4.3 to 5.8 mg/cig and 0.4 to 0.5 mg/cig, respectively, which are within the range of tolerance presented in ISO 8243. In the case of carbonyls, formaldehyde was detected within a range of 8.2 to 14.3 μg/cig, and acetaldehyde was present within a range of 224.7 to 327.2 μg/cig under the ISO smoke regime. Crotonaldehyde was not detected under the ISO regime, and all of the carbonyls showed values 2.3 to 4.5 times higher under the HCI regime than those under the ISO regime. Catechol, which showed a level of 47.0 to 80.5 μg/cig under the ISO regime and 117.5 to 184.7 μg/cig under the HCI regime, was the highest constituent among the phenols. The amount of isoprene was 91.7 to 158.3 μg/cig under the ISO regime and 221.0 to 377.0 under the HCI regime. To summarize, most of the constituents showed a tendency to be detected at levels 2 to 4 times higher under the HCI regime than under the ISO regime. Above all, these results represent the first analysis in Korea from an independent institute of tobacco companies under accreditation of ISO 17025.

마우스 EAE, GVHD 질환에서 CTLA4Ig 융합단백의 면역치료 효과

장성옥,홍수종,조훈식,정용훈,Jang, Seong-Ok,Hong, Soo-Jong,Cho, Hoon-Sik,Chung, Yong-Hoon 대한면역학회 2003 Immune Network Vol.3 No.4

Background: CTLA4 (CD152), which is expressed on the surface of T cells following activation, has a much higher affinity for B7 molecules comparing to CD28, and is a negative regulator of T cell activation. In contrast to stimulating and agonistic capabilities of monoclonal antibodies specific to CTLA-4, CTLA4Ig fusion protein appears to act as CD28 antagonist and inhibits in vitro and in vivo T cell priming in variety of immunological conditions. We've set out to confirm whether inhibition of the CD28-B7 costimulatory response using a soluble form of human CTLA4Ig fusion protein would lead to persistent inhibition of alloreactive T cell activation. Methods: We have used CHO-$dhfr^-$ cell-line to produce CTLA4Ig fusion protein. After serum free culture of transfected cell line we purified this recombinant molecule by using protein A column. To confirm characterization of fusion protein, we carried out a series of Western blot, SDS-PAGE and silver staining analyses. We have also investigated the efficacy of CTLA4Ig in vitro such as mixed lymphocyte reaction (MLR) & cytotoxic T lymphocyte (CTL) response and in vivo such as experimental autoimmune encephalomyelitis (EAE), graft versus host disease (GVHD) and skin-graft whether this fusion protein could inhibit alloreactive T cell activation and lead to immunosuppression of activated T cell. Results: In vitro assay, CTLA4Ig fusion protein inhibited immune response in T cell-specific manner: 1) Human CTLA4Ig inhibited allogeneic stimulation in murine MLR; 2) CTLA4Ig prevented the specific killing activity of CTL. In vivo assay, human CTLA4Ig revealed the capacities to induce alloantigen-specific hyporesponsiveness in mouse model: 1) GVHD was efficiently blocked by dose-dependent manner; 2) Clinical score of EAE was significantly decreased compared to nomal control; 3) The time of skin-graft rejection was not different between CTLA4Ig treated and control group. Conclusion: Human CTLA4Ig suppress the T cell-mediated immune response and efficiently inhibit the EAE, GVHD in mouse model. The mechanism of T cell suppression by human CTLA4Ig fusion protein may be originated from the suppression of activity of cytotoxic T cell. Human CTLA4Ig could not suppress the rejection in mouse skin-graft, this finding suggests that other mechanism except the suppression of cytotoxic T cell may exist on the suppression of graft rejection.

플라스틱 소재의 비소 함유량 분석에 관한 연구

이재인,최기인,고병례,최인식,조훈식,최철호 한국분석과학회 2012 분석과학 Vol.25 No.6

Quantitative analytical condition for arsenic in plastic materials by the flow injection-hydride generation-inductively coupled plasma-atomic emission spectrometry was studied. The plastic samples were dissolved by wet-acid digestion method and microwave-acid digestion method. The reproducibility and accuracy in this method was verified using of certified reference materials(CRMs) CRM-EC680k and CRM-EC681k. The analyical results agrees with certified value within the range of uncertainty. The results of CRM-EC680k wer 4.1~4.3 mg/kg (certified value 4.1±0.5 mg/kg), and the results of CRM-EC681k were 28.9~30.6 mg/kg (certified value 29.1±1.8 mg/kg).

Expression of an artificial gene encoding a repeated tripeptide lysyl-glutamyl-tryptophan in Tobacco plant

Lee, Soo Young,Ra, Kyung Soo,Baik, Hyung Suk,Park, Hee Sung,Cho, Hoon Sik,Lee, Yong Se,Choi, Jang Won 부산대학교 유전공학연구소 2002 분자생물학 연구보 Vol.18 No.-

식물 단백질의 영양가 향상을 위한 일환으로 필수아미노산의 조성이 풍부한 인공단백질을 암호화하는 인공유전자를 담배 식물체에서 발현을 시도하기 위하여, 식물에서 외래유전자의 발현에 널리 사용되는 Cauliflower mosaic virus (CaMV)의 35S promoter를 이중으로 중첩되도록 하고, (Lys-Glu-Trp)이 64번 반복되는 인공유전자 및 nopaline synthase (nos) terminator를 갖고 있는 binary vector pART4-4를 구성하였다. 이 재조합 플라스미드는 Agrobacterium tumefaciens를 이용한 형질전환에 의해 Nicotiana tabacum (Var. Xanthi)으로 도입되었다. Kanamycin이 포함된 신초 유도배지 및 뿌리 유도배지를 이용하여 정상적으로 재생된 담배 식물체로부터 도입된 인공유전자의 발현을 분석하였다. 추출한 genomic DNA를 EcoPI으로 자른 다음 Southern blot 분석에 의하면, 효소 절단 시 예상되는 1.1 kb에서 band를 형성하였으며 각각의 형질전환 식물체에 인공유전자가 1 또는 3 개씩 도입되어 있음을 확인하였다. Northern blot 분석에 의하면 약 1.2 kb 전사체가 비교적 안정하게 발현되었으며, 잎, 줄기, 뿌리로부터 RNA를 분리하여 promoter의 조직 특이성 발현을 분석한 결과, 잎에서 생성되는 RNA가 줄기나 뿌리 조직보다 안정하게 발현되었다. 형질전환 식물체에서 Western blot에 의한 단백질 분석 결과, 잎에서 추출한 단백질로부터 원하는 크기인 33 kDa의 인공단백질이 생성됨을 확인하였으며 발현 수준은 전체 세포 단백질의 0.1%로서 낮은 수준이었다. To investigate expression of the artificial gene encoding a repeated tripeptide lysyl-glutamyl-tryptophan in tobacco plant, the plant binary vector, pART404 has been constructed, which contains the duplicated CaMV 35S promoter, an artificial gene coding for repetitive polymer (Lys-Glu-Trp)_64, and nopaline synthase (nos) terminator. The recombinant expression vector was introduced in Nicotiana tabacum (var. Xanthi) via Agrobacterium tumefaciens-mediated transformation. The transgenic calli selected by kanamycin containing medium were then regenerated to whole plants. Southern blot analysis indicated that five transgenic plants (No. 1, 7, 9, 43, 45) showed the hybridizing signals at 1.1kb of the expected size on ExoRI digestion and each of the transgenic plants contained 1 or 3 copies of the artificial gene inserted into its genome. By northern blot analysis, the size of the hybridized total RNA was estimated to be approximately 1.2 kb and the RNA appeared generally to have the integrity. Western blot indicated that the protein was detected at the position of 33 kDa and the expression level of the polypeptide in the transgenic plant (No. 45) was measured to approximately 0.1% of the total protein.

건조지역 원격탐사 footprint 내 토양수분의 시공간적 변동성 분석

황교택(Hwang Kyotaek),조훈식(Cho Hun sik),이승오(Lee Seung Oh),최민하(Choi Minha) 대한토목학회 2010 대한토목학회논문집 B Vol.30 No.3B

지표에서의 토양수분은 수문학적, 생태학적 과정에서 지표면과 대기 사이의 물과 에너지의 교환을 조절하는 매우 중요한 인자로써 최근 이의 시공간적 변동성에 대한 연구가 활발하게 진행되고 있다. 본 연구에서는 2004년 6~9월에 걸쳐 추진되었던 Soil Moisture Experiment 2004(SMEX04) 프로젝트를 통하여 측정된 미국 Arizona 주의 Walnut Gulch Experimental Watershed 유역에 대한 토양수분 데이터를 이용하여 건조 지역에서의 토양수분의 시공간적 변동성을 통계적 방법으로 해석하였다. 시간 안정도를 분석하여 각 지점의 강우사상에 대한 민감도를 분석하였고 공간 변동성 분석을 통해 유역 내 강우관측소 주변 5개 지점을 대상으로 각 지점의 평균토양수분과 이의 표준편차 및 변동계수와의 관계를 파악하였다. 연구 결과, 대상지역에서 토양수분의 공간적인 분포는 대수정규분포가 적합하다는 것과 건조지역에서 보이는 공통된 특징인 높은 공간적 변동성을 확인할 수 있었다. 또한 시간 안정도 분석을 통해 지점별로 시간과 강우 발생에 대해 민감한 정도를 분석하였으며, 강우사상이 토양수분에 큰 영향을 주는 인자인 것을 확인할 수 있었다. 본 연구에서 도출된 토양수분의 시공간적 변동 특성은 차후 인공위성 토양수분 데이터의 retrieval algorithm을 개선하는데 도움이 될 것이다. Soil moisture is a key factor to control the exchange of water and energy between the surface and the atmosphere. In recent, many researches for spatial and temporal variability analyses of soil moisture have been conducted. In this study, we analyzed the spatio-temporal variability of soil moisture in Walnut Gulch Experimental Watershed, Arizona, U.S. during the Soil Moisture Experiment 2004 (SMEX04). The spatio-temporal variability analyses were performed to understand sensitivity of five observation sites with precipitation and relationship between mean soil moisture, and its standard deviation and coefficient of variation at the sites, respectively. It was identified that log-normal distribution was superior to replicate soil moisture spatial patterns. In addition, precipitation was identified as a key physical factor to understand spatio-temporal variability of soil moisure based on the temporal stability analysis. Based on current results, higher spatial variability was also observed which was agreed with the results of previous studies. The results from this study should be essential for improvement of the remotely sensed soil moisture retrieval algorithm.

손목의 원위 교차증후군 - 3례 보고 -

남승오,신동주,김태은,김성욱,조훈식 대한수부외과학회 2011 대한수부외과학회지 Vol.16 No.4

원위 교차증후군은 장 및 단 요 수근 신전 건과 장 무지 신전 건이 교차하는 부위에서생긴 제 2, 3 신전 건 구획의 동시 건초염 또는 건증을 의미한다. 일반적인 교차증후군과는 다른 원위 교차증후군 3예를 경험하였기에 문헌 고찰과 함께 보고하고자한다. Distal intersection syndrome indicates simultaneous tenosynovitis or tendinosis of the second and third extensor compartment where extensor pollicis longus cross with the tendons of the second extensor compartment. We report three cases of distal intersection syndrome which differ from usual intersection syndrome.

문턱 전압 안정을 위한 Substrate Bias 회로 시스템의 설계 및 검증

김남용(Namyong Kim),조훈식(Hunsik Cho),손일헌(Ilhun Son),이영희(Younghee Lee) 대한전자공학회 1997 대한전자공학회 학술대회 Vol.1997 No.11