Au를 공침한 SnO₂후막센서의 가스 감응 특성

성정훈,강대원,이윤수,임준우,홍영호,이덕동 경북대학교 센서기술연구소 1998 센서技術學術大會論文集 Vol.9 No.1

High selective and sensitive thick film type methane gas sensors were fabricated and their sensing characteristics for various hydrocarbon gases were investigated. Raw material, SnO_(2)/Au, prepared by coprecipitation was even grain size. SEM, TEM, BET and XRD analyses were carried out for investigation of surface morphology and crystalline structure. The thick film devices using the above materials exhibited high sensitivity to methane gas at the operating temperature of 400°C. The sensitivity of SnO_(2)/Au+Pd thick film devices to methane gas was higher than that to the other hydrocarbon gases such as iso-butane and propane. The optimal adding amounts of Au and Pd were 1wt.% and 3wt.%, respectively. The sensitivity, S, is defined as {(R_(A)-R_(G))/R_(A)}><100, which R_(A) and R_(G) are resistance in air and that in the gas ambient, respectively.

색상 측정 기기를 이용한 복합레진 적층 수복과 단일 수복의 색상 비교 분석

송영상,김자현,이빈나,장지현,장훈상,황윤찬,오원만,황인남 大韓齒科保存學會 2012 Restorative Dentistry & Endodontics Vol.37 No.2

Objectives: This study analyzed the difference in color caused by different thickness in enamel layer of composite resins when applied with single and layering placement technique, and evaluated if the results agreed with the shade guide from the manufacturers to verify reliability of the color matching process of the manufacturers. Materials and Methods: For single composite resin samples, 6 mm diameter and 4 mm thickness cylindrical samples were fabricated using Ceram-X mono (DENTSPLY DeTrey) and CIE L*a*b* values were measured with spectrophotometer. Same process was done for layering compositie resin samples, making 3 dentinal shade samples, 4 mm thickness, for each shade using Ceram-X duo (DENTSPLY DeTrey) and enamel shade resins were layered in 2 mm thickness and CIE L*a*b* values were measured. These samples were ground to 0.2 mm thickness each time, and CIE L*a*b* values were measured to 1 mm thickness of enamel shade resin. Results: Color difference (△E*) between single and layering composite resin was 1.37 minimum and 10.53 maximum when layering thicknesses were between 1 mm and 2 mm and 6 out of 10 same shade groups suggested by manufacturer showed remarkable color difference at anythickness (△E* > 3.3). Conclusion: When using Ceram-X mono and duo for composite resin restoration, following the manufacturer's instructions for chossing the shade is not appropriate, and more accurate information for Ceram-X duo is needed on the variation and expression of the shades depending on the thickness of the enamel. (Restor Dent Endod 2012;37(2):84-89)

유동성 복합레진의 마모저항성에 관한 연구

윤연희,김정욱,이상훈,한세현 大韓小兒齒科學會 2002 大韓小兒齒科學會誌 Vol.29 No.2

시술시간을 줄이는데 유리한 재료인 유동성 복합레진을 유구치부에 사용하려고 고려할 때 중요한 물성 중 하나는 마모저항성이다. 이 연구의 목적은 유동성 복합레진의 마모저항성을 일반복합레진의 마모저항성을 비교하는 것이다. 실험에 사용된 유동성 복합레진으로 1군에서는 Arabesk flow (VOCO, Germany), 2군에서는 Tetric flow (Vivadent, Liechtenstein), 3군에서는 Aeliteflow (Bisco, U.S.A), 4군에서는 Filtek flow (3M Dental Co, U.S.A)을 사용하였으며 대조군으로 사용한 5군의 복합레진은 Z100 (3M Dental Co, U.S.A)이었다. 시편들(n=10)은 두께 2mm, 지름 5mm의 원통모양으로 제작하여 마모시험 전 37℃의 증류수에서 7일 동안 담가 놓았다. 제1소구치와 레진시편을 MTS 시스템에서 2Hz로 50,000회 접촉, 마모시켰다. 마모시험시 lateral excursion은 0.4mm, 교합력은 2-100N의 조건이었다. 마모시험후 마모된 부피, 최대마모깊이, 재료자체의 표면경도를 측정하였고 마모되지 않은 표면과 마모가 일어난 표면을 주사전자현미경으로 관찰하였으며 다음과 같은 결과를 얻었다. 1. 마모된 부피는 3군에서 가장 적었고 4군에서 가장 많았으며 3군<1군<2군<5군<4군의 순서로 증가하였다. 2. 3군, 1군, 2군, 5군이나 4군에 비해 통계적으로 유의하게 마모부피가 적었다(P<0.05). 그러나, 3군, 1군, 2군 사이에서와 5군, 4군 사이에서는 각각 통계적으로 유의한 차이가 없었다. 3. 최대마모깊이는 1군에서 가장 낮았고, 4군에서 가장 깊었으며 1군<3군<5군<2군<4군의 순서로 증가하였다. 4. 5군의 표면경도는 다른 유동성 복합레진군에 비해 통계적으로 유의하게 높았으나(P<0.05). 마모부피나 최대마모깊이와는 통계적으로 유의한 상관관계를 보이지 않았다. 5. 마모되지 않은 표면과 마모가 일어난 표면을 주사전자현미경으로 관찰한 결과, 유동성 복합레진군과 5군 사이에 마모양상이 다르게 나타나는 것을 볼 수 있었다. When we use the flowable resin on the primary molars for quick handling, one of the most important property is the wear resistance. This study was performed to compare the wear resistance characteristics of four flowable composite resins [Arabesk flow (group 1), Tetric flow (group 2), Aeliteflow (group 3), Filtek flow (group 4)] to that of one control composite resin [Z100 (group 5)]. Specimen discs(n=10), 10mm wide and 2mm thick, were stored in distilled water at 37℃ for 7 days prior to testing. The specimens were subjected to 50,000 strokes at 2Hz on the MTS system. During the test, the following parameters were maintained: the ;atera; excursion at 0.4mm, occlusal force at 2-100N with a force profile in the form of a half sine wave. The measurements of volume loss, depth of wear, and Vicker's hardness number of composite resins, and SEM obserbations of the polished and abraded surfaces were established. One-way ANOVA and Scheffe's multi-ple comparison test were employed to detect statistically significant differences among the flowable composite resin group and the control composite group at P<.05. The following results were obtained: 1. Group 3 showed the least volume loss, while group 4 showed the greatest. The mean volume loss increased in the following order: group 3<group 1<group 2<group 5<group 4. 2. Group 3, group 1, and group 2 showed significantly lesser volume loss compared to group 5 and group 4(p<0.05). However, There was no statistically significant difference among group 3, group 1 and group 2. There was no statistically significant difference between group 5 and group 4. 3. Group 1 showed the shallowest depth of wear, while group 4 showed the deepest. The mean depth of wear increased in the following order: group 1<group 3<group 5<group 2<group 4. 4. Group 5 showed significantly highest hardness value compared to the flowable composite resin groups(p<0.05), but there was no correlation between wear resistance and Vickers hardness number. 5. SEM observation of the unworn and worn surfaces revealed the differences in the wear appearance between the flowable composite resin groups and the control.

Kleine-Levin 증후군 1예

이승훈,이성훈,김상윤 대한신경과학회 1999 대한신경과학회지 Vol.17 No.5

소장 질환이 의심되는 환자에서 캡슐내시경과 CT 소견의 비교

이성수,홍성숙,김정훈,김연수,김진오,권석범,박성태,장윤우,최득린,권귀향 순천향의학연구소 2007 Journal of Soonchunhyang Medical Science Vol.13 No.1

..

교정용 미니 임플랜트의 cutting flute의 길이 및 형태에 따른 식립 및 제거 토크의 비교

윤순동,임성훈 대한치과교정학회 2009 대한치과교정학회지 Vol.39 No.2

Objective: The purpose of this study was to evaluate the effect of length and shape of cutting flute on mechanical properties of orthodontic mini-implants. Methods: Three types of mini-implants with different flute patterns (Type A with 2.6 mm long flute, Type B with 3.9 mm long and straight flute, Type C with 3.9 mm long and helical flute) were inserted into the biomechanical test blocks (Sawbones Inc., USA) with 2 mm and 4 mm cortical bone thicknesses to test insertion and removal torque. Results: In 4 mm cortical bone thickness, Type C mini-implants showed highest maximum insertion torque, then Type A and Type B in order. Type C also showed shortest total insertion time and highest maximum removal torque, but Type A and B didn't showed statistically significant difference in insertion time and removal torque. In 2 mm cortical bone thickness, there were no significant difference in total insertion time and maximum removal torque in three types of mini-implants, but maximum insertion torque of Type A was higher than two other Types of mini-implants. Conclusions: Consideration about length and shape of cutting flute of mini-implant is also required when the placement site has thick cortical bone. 본 연구는 self-tapping screw의 특징적 구조인 cutting flute의 길이 및 형태 변화에 따른 미니 임플랜트의 식립 및 제거 토크를 비교해보기 위해 시행되었다. 외경, 내경, 길이 및 pitch 등 다른 조건이 모두 동일하고 cutting flute의 형태만 다른 세 종류의 미니 임플랜트를 사용하였다(A군; 2.6 mm 길이의 flute가 형성된 그룹, B군; 3.9 mm의 길이이면서 직선형의 flute를 갖는 그룹, C군; 3.9 mm의 길이이면서 나선형의 flute를 갖는 그룹). 골밀도를 균일하게 하기 위해 실험용 인공골(Sawbones Inc., USA)을 사용하였으며, 수직력 및 회전속도를 일정하게 하기 위해 구동식 토크 시험기를 이용하였다. 그 결과 다음과 같은 결론을 얻었다. 총 삽입 시간은 2 mm 두께의 피질골 시편에서는 세 군간에 차이를 보이지 않으나, 4 mm 두께의 피질골 시편에서는 C군 > B군 > A군 순으로 짧은 삽입 시간을 보였다. 최대 삽입 토크는 2 mm 두께의 시편에서는 A군이 다른 두 군에 비해 높은 값을 보이나, 4 mm 두께의 피질골 시편에서는 C군 > A군 > B군 순으로 높은 값을 보였다. 최대 제거 토크는 2 mm 두께의 피질골 시편에서는 세 군 사이에 차이가 없으나, 4 mm 두께의 피질골 시편에서는 C군이 다른 두 군에 비해 높은 값을 보여주었다. 이상의 결과로 보아 피질골이 두꺼운 부위에 미니 임플랜트를 식립할 경우 cutting flute의 길이 및 형태 또한 고려하여 미니 임플랜트를 선택하는 것이 바람직하다.

콩에서 발생하는 강낭콩일반모자이크바이러스(BCMV)와 땅콩위축바이러스(PSV)의 저항성 평가

이영훈, 윤영남, 강범규, 김현영, 최만수, 구성철, 김현태, 윤홍태, 이수헌, 백인열 忠北大學校 農業科學硏究所 2014 農業科學硏究 Vol.30 No.2

It has been reported several viral diseases in soybean. The occurrence of Bean common mosaic virus and Peanut stunt virus are able to induce severe problem because the main breeding target for viral disease was focused on Soybean mosaic virus. BCMV is a spcies of the genus Potyvirus of the family Potyviridae. BCMV reduces yield by as much as 80% and also adversely affects seed quality in common bean. BCMV has a worldwide distribution because of its high rates 35% of transmission via seeds produced by plants systemically infected prior to bloom. PSV is a species of the genus Cucumovirus of the family Bromoviridae. PSV has been reported to be economically damaging on beans worldwide. Although the virus is reportedly seed transmissible at very low rates, infected plants rarely produce pods with normal viable seeds. The most satisfactory management method of viral diseases such as BCMV and PSV is the use of resistant cultivars and healthy seed. For the overcome of genetic resistance by new virus such as BCMV and PSV, virus diseases monitoring and researches need to study deeply and continually. In this study, we conducted the resistance screen on BCMV and PSV for selection of resistance cultivars. We inoculated on 128 cultivars with PSV and BCMV respectively. These cultivars were classified through pathogenic response such as resistance, necrosis and susceptibility. In addition, 99 and 66 resistant cultivars were confirmed against PSV and BCMV respectively.

프랙탈변환 방법에 의한 컬러 영상 압축에서의 최적 컬러축약률 및 범위 이동

명연수,이상훈,이형원,임철홍 인제대학교 1993 仁濟論叢 Vol.9 No.2

프랙탈변환을 이용하여 256가지 색을 가진 영상을 압축하는 모사 실험을 수행하였다. 영역의 크기, 컬러축약률,범위 이동치 변화에 따른 압축 영상의 평균 강도 차를 비교하여 최적 압축 조건을 조사하였다. By using the fractal transform we perform the simulations that compress the 256-color real world images. The optimal compression conditions are examined by comparing the compressed images resulting from the variations of the size of domain, ratio of color contraction and range-shift.

Carbosulfan의 피부자극성, 안점막 자극성 및 피부감작성등의 알러지성 효과에 관한 연구

이상훈,이동연,백경진,김태원,정두순,임종환,김명석,박병권,윤효인 충남대학교 수의과대학 동물의과학연구소 2004 動物醫科學硏究誌 Vol.12 No.-

Many studies have been published on the human health effects of carbosulfan toxicity. Carbosulfan used as an insecticide can produce an irritating and allergenic effect when acting on the skin. In this study, a sensitization test on albino guinea pigs and intradermal reactivity and occular irritation test on albino rabbits were carried out with carbosulfan. Signs of acute skin inflammation appeared along with the clinical symptom of chronic dermatosis caused by the solution irritating characteristics. Moreover, carbosulfan showed severe eye irritation with conjuctival redness and severe opacity on cornea. Preventive measures should involve workers' obligatory instructions on the noxious impact on human skin and strict observance of industrial safety rules.

四肢의 Scar Revision에 있어 Modified Millard's Trick의 利用

金勳男,崔性玔,李斗炯,李圭源,皇甫宗演 大韓成形外科學會 1976 Archives of Plastic Surgery Vol.3 No.1

No matter how various methods may be tried, for scar repair of extremities, the results were not so acceptable unfortunately. Of these procedures, Millard's trick (The Double-Breasted Vest Principle) is the one of most popular methods and which has been loved by many surgeons, esp, plastic surgeons, up to date. However, even this method couldn't satisfied us, because of undesirable disadvantages, and our new repair method, entitle "Modified Millard's Trick Method" was designed with supplement of disadvantages of Millard's Tric in mind and has been used in attempt to prevent recurrence of the usual spread. This approach is advocated for scars in area where stretch-ing is usual or where a careful regular repair has failed to prevent it. If there is any depression associated with the scar, this is corrected simultaneously by advancing both skin flaps in opposite direction. We have tired this new method for 1- cases of patients, esp. for relatively wide linear scar (over 5cm) on extremities.