구강병으로 인한 학업손실실태와 그 연관요인에 관한 연구

윤영만,이흥수 원광대학교 치의학연구소 2002 圓光齒醫學 Vol.11 No.2

To prepare basic data for oral health promotion of elementary and middle school students through the survey of the status of school loss on account of oral diseases and the examination of the related factors, a questionnaire survey was conducted for 3,080 students. School loss was investigated based on the experiences of absences and leaving school early, which had happened from oral diseases. Also the restricted activities related with schoolwork such as dining and sleeping were surveyed. The independent variables were oral health behaviors and socioeconmic factors such as sex, age of their parents, education level of their fathers, family income. Factors related with school loss and the restricted activities were analyzed by the multiple logistic regression method. The results of this study were as follows. 1. The 2.37% of students were absent on account of oral disease at elementary and midlde school. Also, the annual average days of absence and early leaving school for elementary school students were 0.05, while the average days for middle school students were 0.07. 2. The rate of students' restricted activity were 39.1% at elementary school and 55.7% at middle school. 3. The elementary students whose mothers are employed showed higher probability of absence due to oral diseases than the students whose mothers are unemployed. 4. The elementary students who live in rural regions showed higher probability of absence and restricted activities on account of oral diseases than the students who live in urban regions. 5. School loss of middle school students was correlated to a load of schoolwork and score of schoolwork. 6. Middle school students who do not trust oral treatment showed higher probability to experience the restricted activities due to oral diseases than the students who trust in it.

일본 바이오매스 활용 정책 및 기술현황

윤영만,유호천,김창현,최은희,윤성이,Yoon, Young-Man,Yoo, Ho-Chun,Kim, Chang-Hyun,Choi, Eun-Hee,Yoon, Sung-Yee 한국유기농업학회 2012 韓國有機農業學會誌 Vol.20 No.4

Based on the general policy called "Green Growth", the Korean government planed to establish a biomass town in South Korea in order to recover energy from organic waste and to substitute for fossil fuel at rural region. Technical and financial support for the establishment of biomass town was insufficient so far. There are some policies to support biomass town establishment, however financial support from several Korean ministries seemed not to have been used efficiently. Some policies are planned excessively so that they cannot be realized on time. Therefore, there is a need to analyze the status of biomass utilization technology and policy in Japan from the point of view of an external biomass expert, since biomass utilization technology and policy of Japan take good achievement during the many developed countries. For the analyzing of technology and policy in Japan, literatures concerned biomass management policy and biomass town design were collected by visiting Japan Ministry of Agriculture, Forestry and Fisheries and interview of public officials in charge was carried out. There are several implications for the promotion of Korean policy concerned with biomass utilization and biomass town establishment.

필러 배합에 따른 치면열구전색재의 법랑질 결합 및 강도특성

윤영만,이용근,이흥수 대한구강보건학회 2000 大韓口腔保健學會誌 Vol.24 No.1

One of the characteristics that can predict the cariostatic effect of dental pit and fissure sealants is wear resistance of the material, and those for the expectation of the retention rate is the bond strength to enamel. Although the Bis-GMA resin based sealants are widely used, their mechanical properties are lower than those of composite filling resins because of lower cross-linking of the material. After incorporation of filler to the resin sealant, almost all the mechanical properties are improved except tensile strength. Incorporation of filler also results in higher abrasion resistance, and easy discrimination of the sealant. However there are a few reports on the mechanical properties and bond strength of sealant after incorporation of various amount of filler to the same resin for sealant. The purpose of this study was to determine the bond characteristics to enamel and the biaxial fracture strength of dental pit and fissure sealants after incorporation of various amount of glass fillers to the same unfilled resin sealant. Light cured pit and fissure sealants(CO and TM) were used as controls. Glass filler was incorporated in the chemically cures resin sealant(HP) with the ratio of 10, 30 and 50 wt.%, and was used as experimental groups, Two types of fillers, silane-coated and not coated, were used. For bonding test, flat enamel surface was made on sound premolar tooth by grinding with #600 silicone carbide paper. This surface was ached with 37% phosphoric acid for 30 second, and sealant filled gelatin capsule(3㎜ diameter) was attached to this surface. After immersion in 37% distilled water for 24 hours, shear bond properties were measured with a universal testing machine(Zwick 020, Germany) with the cross-head speed of 1㎜/min. From the lid-deflection calve obtained, shear bond strength, displacement at bond failure and elastic modules ratio was calculated. For biaxial fracture strength test, diameter of 10㎜ and thickness of 2㎜ specimens were made with the same materials as in bonding test. After immersion in 37℃ distilled water for 24 hours, biaxial fracture properties were measured with a universal testing machine(Zwick 020, Germany) with the cross-head speed of 0.5㎜/min. From this experiment, the following results were obtained. 1. The shear bond strength of unfilled HP to enamel surface was 13.870㎫, and those after filler incorporation were 18.956-19.684㎫. 2. The shear bond strength to enamel surface increased significantly after incorporation of filler with the ratio of 10, 30 and 50 wt.%(p<0.05), and the incorporation ratio did not influence on the shear bond strength(p>0.05). Silane treatment of the filler did not influenced on the shear bond strength(p>0.05). 3. The biaxial fracture strength of TM was 170.69㎫, and this was significantly higher than that of unfilled HP(p<0.05). Incorporation of the filler with the ratio of 10, 30 and 50 wt.% resulted in significantly lower biaxial fracture strength compared with that of unfilled HP(p<0.05). 4. In HP with the incorporation of filler 10 or 30 wt.% group, the biaxial fracture strength of silane coated and not-coated filler group was significantly different(p<0.05).

바이오가스 생산시설의 비용 편익 사례 분석

윤영만,박현태,김연중,한혜성 한국농촌경제연구원 2012 농촌경제 Vol.35 No.4

This study conducted a case study analyzing the cost and benefits of biogas plants that use livestock manure to produce biogas. The purpose was to review the possibility of expanding the facilities across the country. According to the analysis results, it was found that in most cases economic viability would be very low if the revenue is earned through the selling of surplus electricity only. If we consider the sales revenue from surplus power as the direct benefit (Scenario 1), the compensation rate would be 24.8% of total facility cost. However, in Scenario 2 where we consider private investment as the only cost, the compensation rate would be 34.0% of the total cost. It was found that if indirect benefit is taken into account, only the biogas facility in Jeju Island would generate an economic benefit of 381 won/㎥. In the cost analysis of private investment, it was estimated that the economic benefit of the biogas plants would be 2,565~4,809 won/㎥, that is, excluding two plants in Suncheon and Changnyeong that are built with private investment only and another two plants in Anseong that are built for experimental purpose only. Therefore, in order to improve the economic viability of manure biogas plants, government support is needed more than anything else to share the initial facility cost.

저선량 ${\gamma}$ 선 조사가 배추와 무 종자의 발아와 양분흡수에 미치는 영향

윤영만,김남범,김재성,김정규,Yoon, Young-Man,Kim, Nam-Bum,Kim, Jae-Sung,Kim, Jeong-Gyu 한국환경농학회 1999 한국환경농학회지 Vol.18 No.4

배추와 무의 영양생리에 대한 저선량${\gamma}$선에 의한 자극작용의 영향을 파악하고자 1998년산 흑진주배추, 1995년산 서림엇갈이배추, 1998년산 청운무 종자에 1에서 10Gy의 저선량 ${\gamma}$선을 조사하고 생육시기에 따른 생장량과 무기양분의 변화를 분석하였다. 공시된 배추품종들은 조사선량의 증가에 따라서 발아율과 건물생산량이 증가하는 경향을 보였다. 건물생산의 증가는 흑진주배추에서 가장 현저하여 10Gy 처리구에서 143%로 증가되었고, 서림엇갈이배추는 10Gy에서 138%로 증가하였다. 청운무는 ${\gamma}$선 조사에 따른 발아율과 건물생산량의 일관된 경향성을 보이지 않았다. 무기영양소들의 함량변화는 선량-반응 곡선의 ${\gamma}$ 또는 ${\delta}$형을 나타내 ${\gamma}$선에 의한 자극효과가 일부처리구에서 나타나기는 하였지만 일반적 현상이라고 인정하기 어려웠다. 따라서 저선량 ${\gamma}$조사가 배추와 무의 영양생리에 미치는 영향을 정확하게 파악하기 위한 연구결과의 집적이 필요할 것으로 판단된다. To investigate hormetic effect of low dose ${\gamma}$-ray on the uptake of mineral nutrients in Chinese cabbage (Brassica campestris var. Hekjinju var. Surim and) and radish (Raphanus sativas var. Chung-un), seeds of these plants were irradiated with the dose of 1 to 10 Gy. Germination rate and dry weight were examined at pot experiment in greenhouse. Samples for analysis of mineral nutrient were harvested at 17 days and at 59 days after seedling and were analyzed by ICP. Brassica campestris varieties showed higher germination rate and dry weight production with increasing ${\gamma}$ ray dose. Dry weight of Hekjinju Surim and were 143% and 138% at 10Gy dose. respectively. There was no tendency in germination rate and dry weight production for Raphanus sativas var. Chung-un with ${\gamma}$-ray irradiation. The pattern of mineral nutrient content of these plants showed ${\gamma}$ or ${\delta}$ type of dose-reaction curve with no siginificant. This investigation suggests that the more results can be required to understand the hormetic effect of low dose ${\gamma}$ ray on the uptake of mineral nutrient for these plants.

양돈 바이오매스의 퇴,액비화 방법별 경제성 평가

윤영만,김연중,김창현 한국농촌경제연구원 2009 농촌경제 Vol.31 No.6

친환경 농업기술로서의 규소의 잠재적 효용성

윤영만,장준영,김정규 고려대학교 자연자원연구소 2000 自然資源科學硏究 Vol.8 No.-

유리섬유복합소재를 이용한 지중매설형 승하강식 홍수방지 벽체구조물

윤영만 한국재난정보학회 2013 한국재난정보학회 논문집 Vol.9 No.4

제방 월류방지 대체공법으로 전도식, 부력식 홍수방지벽을 국내ㆍ외에서 개발하는 실정이다. 그러나, 사전점검 불가 및 유지관리 문제점이 있어 본 연구에서는 국내ㆍ외 최초로 경량 재질이면서 강도가 우수한 유리섬유복합소재를 이용한 승하강식 홍수방지 벽체구조물을 연구ㆍ개발하였다. 개발된 홍수방지 벽체구조물은 수치해석을 통해 구조적 안정성과 함께 현장 적용성을 제시하여 공사비를 약 87%~95%로 감소시키고 벽체구조물 내부에 고무지수부재를 설치하여 차수성이 확보되는 것을 확인하였다.

교량에 설치된 도시가스배관의 안전관리에 관한 연구

윤영만,손상근,최도균,이수경 한국가스학회 2018 한국가스학회지 Vol.22 No.1

In this study, 398 city gas pipe systems installed on the bridges were surveyed and analyzed classified characteristics about the ages, length, and remote isolation devices installed or not. As a result of analysis, 43.0% pipes have been used more than 20 years and 89.4% do not have remote cut-off devices, so this study suggest safety management ways for the issues. Chosen 76 pipes were researched stress strain characteristics by CAESAR-Ⅱ which is a specialized program for stress analysis. And, when a loop is installed on the bridge pipe, effect on code stress by the location and size of the loop was performed. This study can help to improve safety level by revising criteria of new installation, inspection and diagnostic. 이 논문에서는 도시가스 배관 중 교량에 설치된 배관 398개소에 대해 현황을 조사하고, 배관을 설치연도별, 길이별, 원격차단장치 설치여부 등 특성별로 분류하여 분석하였다. 분석결과 20년 이상 장기사용배관이 43.0% 를 차지하고 있었고, 원격차단장치 미설치 교량배관은 89.4%에 달하는 등 드러난 현상에 대한 안전관리 방안을제시하였다. 또한 조사된 교량설치 배관 중 76개소를 선정한 후 응력해석 전용프로그램인 CAESAR-Ⅱ를 이용하여 응력특성을 연구하고, 교량배관 중 루프관을 설치할 경우 루프관의 위치 및 크기가 배관의 합성응력에 미치는 영향을 분석하였다. 본 연구의 결과를 통해 교량 배관의 설치, 검사 및 진단 기준 개선 등에 활용하여 교량설치 배관에 대한 안전성 향상에 도움이 될 수 있을 것으로 판단한다.

포스터발표논문초록 / 토양 비료 분야 ( SF : Siol & Fertilizers ) : SF06 - 토양수분함량과 자란의 초기 생육

윤영만,장미영,박천호,김정규 한국토양비료학회 1998 한국토양비료학회 학술발표회 초록집 Vol.- No.-