Comparison with Threshold Limit Value (TLV) of Menthol Cigarettes between Expert and Consumer Panel

이승용,이환우,김영호,Lee Seung-Yong,Lee Whan-Woo,Kim Young-Hoh The Korean Society of Tobacco Science 2006 한국연초학회지 Vol.28 No.1

Threshold limit value (TLV) test between expert and consumer panel was conducted about absolute, recognition and difference threshold respectively. And we tried to suggest appropriate and minimum acceptable menthol concentration level by consumer panel. Determination of threshold value was based on ASTM E 679-79 method by forced-choice ascending concentration series. In addition, a semi-ascending paired difference method was referred to conduct test. The group threshold value was determined as the value of geometric mean individual threshold. The smokers were dividend by two groups, trained and consumer panel. Trained panel was selected according to sensitivity to menthol discrimination. Consumer panel wasrecruited in proportion as population ratios including female smokers. They were all over twenty years old volunteers and summed up thirty four persons. In terms of sensor evaluation, overall difference test with seven-category scale by both trained and consumer panelists were done. On judging correct or incorrect answer, two by three cut-off levels applied to. Every test was conducted with two sessions, before smoking and during smoking period. And, only two samples served each paneI per test with regard to sensory fatigue and reliable results. All tests were replicated, and in total 32 times per panelist. In conclusion, the recognition threshold about consumer and expert panel was 358 ppm/cig. and 276 ppm/cig. in separately. Besides, absolute and difference thresholds were obtained also. And, we conduct difference threshold test with two different ways, upward and downward. And, The results of each method were 246, 195 ppm/cig., 1414, 1336 ppm/cig. and 1047, 972 ppm/cig.

다중위상 지연고정루프 기반의 위상 선택기와 분수 분주형 위상고정루프를 이용하는 121.15 MHz 주파수 합성기

이승용,이필호,장영찬,Lee, Seung-Yong,Lee, Pil-Ho,Jang, Young-Chan 한국정보통신학회 2013 한국정보통신학회논문지 Vol.17 No.10

본 논문에서는 on-chip oscilloscope의 sub-sampler를 위한 클록을 생성하기 위한 두 가지 방식의 주파수 합성기를 제안한다. 제안하는 두 가지의 주파수 합성기는 지연고정루프 기반의 위상 선택기를 이용한 구조와 분수 분주형 위상고정루프를 이용하는 구조를 가지며 시뮬레이션 결과를 비교함으로써 각 구조의 특성이 분석된다. 제안된 두 회로 모두 1V 공급전압을 이용하는 65-nm CMOS 공정에서 설계되었으며, 125 MHz의 주파수를 가지는 입력 클록에 대해 121.15 MHz의 주파수를 가지는 출력 클록을 생성한다. 지연고정루프 기반의 위상 선택기를 이용한 주파수 합성기는 0.167 $mm^2$의 면적을 가지며 출력 클록은 2.88 ps의 지터 특성을 나타나며, 4.75 mW의 전력을 소모한다. 분수 분주형 위상고정루프를 이용한 주파수 합성기는 0.662 $mm^2$의 면적을 가지며 7.2 ps의 지터 특성을 나타내며, 1.16 mW의 전력을 소모한다. Two frequency synthesizers are proposed to generate a clock for a sub-sampler of an on-chip oscilloscope in this paper. These proposed frequency synthesizers are designed by using a multi-phase delayed-locked loop (DLL)-based phase selector and a fractional-N phase-locked loop (PLL), and they are analyzed by comparing simulation results of each frequency synthesizer. Two proposed frequency synthesizers are designed using a 65-nm CMOS process with a 1V supply and output the clock with the frequency of 121.15 MHz when the frequency of an input clock is 125 MHz. The designed frequency synthesizer using a multi-phase DLL-based phase selector has the area of 0.167 $mm^2$ and the peak-to-peak jitter performance of 2.88 ps when it consumes the power of 4.75 mW. The designed frequency synthesizer using a fractional-N PLL has the area of 0.662 $mm^2$ and the peak-to-peak jitter performance of 7.2 ps when it consumes the power of 1.16 mW.

2개의 H형강이 합성된 가설교량 상부구조의 구조거동 평가

이승용,박영훈,박상현,Lee, Seung Yong,Park, Young Hoon,Park, Sang Hyun 대한토목학회 2013 대한토목학회논문집 Vol.33 No.1

본 논문에서는 가설교량의 지간장 증대를 위하여 중앙부 주거더 H형강 상단에 작은 H형강을 보강하고, 지점부 주거더 H형강 하단에 강판을 합성시킨 가설교량을 설계 및 시공하여 현장재하시험으로 실 거동을 분석하고, 해석적 전단좌굴강도와 비선형 거동을 일반 가설교량과 비교 평가하였다. 그 결과, 현장재하시험에 의하여 제안된 가설교량의 실제 거동이 설계 과정에서 고려된 거동과 일치하는 것으로 나타났으며, 본 연구의 설계조건에 있어서 제안한 가설교량의 해석적 전단좌굴강도가 일반 가설교량의 전단좌굴강도보다 약 40% 정도 높은 것으로 분석되었다. 또한 제안된 가설교량의 해석적 극한강도는 일반 가설교량 보다 높은 것으로 평가되어 현장여건의 필요에 의해 제안한 가설교량을 적용할 수 있을 것으로 판단된다. In this study, in order to increase the span length, the temporary bridge which the center part of span is strengthened by small H-beam and the end part of span is strengthened by steel plate is designed and constructed. Real behavior of proposed temporary bridge is analyzed by field loading test. Analyzed shear buckling strengths and nonlinear behavior of suggested temporary bridge are compared with the those of general temporary bridge. From the field loading test results, it is analyzed that real static behavior of suggested temporary bridge is agree with the analyzed behavior which is considered in design process. Under the proposed design condition, it is investigated that the shear buckling strength of suggested temporary bridge is about 40% higher than that of general temporary bridge, and the ultimate strength of suggested temporary bridge is about higher than that of general temporary bridge. From the study results, it is concluded that the proposed temporary bridge can be applied by the needs of field condition.

공학교육 만족도 지수에 기반한 전략연구

이승용,윤재용,김태현,손소영,Lee Seung-Yong,Yoon Jae-Yong,Kim Tae-Hyun,Sohn So-Young 한국공학교육학회 2005 공학교육연구 Vol.8 No.3

요즘 거론되는 이공계의 위기는 국가 경쟁력을 저해하는 중대한 문제이다. 본 연구에서는 이공계의 위기를 구체적으로 정량화하기 위해, 구조방정식모형을 이용하여 전공과 인성적 측면에서의 학생들의 공학교육 만족도 지수를 산출하였다. 도출된 지수를 바탕으로 공학 교육의 현 주소를 데이터 마이닝 기법을 활용하여 분석하고 그 결과를 토대로 공학 위기 극복을 위한 발전적 전략을 제시하였다. The crisis of science-engineering field is a significant problem which hinders the improvement of national competitiveness. In this study, we use a structural equation model to propose two kinds of satisfaction indices of engineering education: m index for major and p index for personality. They are used to improve the current situation of engineering education in Korea. Based on the resulting feedback information, we suggest several strategic plans for science-engineering field.

과대공을 갖는 고장력 볼트 이음부의 역학적 거동에 관한 실험 및 해석적 연구

이승용,박영훈,조선규,장동일,Lee, Seung Yong,Park, Young Hoon,Cho, Sun Kyu,Chang, Dong Il 한국강구조학회 1998 韓國鋼構造學會 論文集 Vol.10 No.3

To evaluate the mechanical behavior and the compressive stress distribution in high tension bolted joints according to the size of bolt hole, the experimental and analytical studies are performed with enlarging bolt hole size. In experimental study, the static test is performed to measure the slip coefficient, and the fatigue test is also performed to evaluate the fatigue strength and failure pattern of fatigue crack. In analytical study, the compressive stress distribution is investigated by using the finite element analysis. From the result of experimental study, the slip coefficient and fatigue strength of the high tension bolted joints with oversize hole are not much different but somewhat it has decreased. These are because the size of bolt hole is larger than the holes of nominal size, therefore the width of clamping force is decreased and the compressive stress distribution area is smaller, this is certificated in the finite element analysis. In addition, the origin of fatigue crack in the oversize holes is closer to the hole than in the holes of nominal size, consequently it is investigated that the origin of fatigue crack is intimately associated with the compressive stress distribution which is formulated by the clamping force in both base metal and splice plate. 볼트 구멍의 크기가 고장력 볼트 이음부의 역학적 거동 및 내부 압축응력 분포에 미치는 영향을 살펴보기 위하여 과대공 및 표준공을 갖는 고장력 볼트 이음부에 대한 실험 및 해석적 연구를 실시하였다. 실험적 연구에서는 정적 인장시험과 피로시험을 실시하여 미끄러짐 특성, 피로강도 및 피로파단 양상을 평가하였으며, 해석적 연구에서는 유한요소해석을 통하여 내부 압축응력의 분포영역을 밝히고, 내부 압축응력의 분포가 역학적 거동에 미치는 영향을 평가하였다. 실험결과, 과대공을 갖는 고장력 볼트 이음부의 미끄러짐 계수와 피로강도는 표준공을 갖는 이음부와 비교하여 큰 차이는 없으나 다소 감소하는 경향이 나타났다. 이러한 원인은 과대공 시험편의 경우 볼트 구멍의 크기가 표준공 시험편과 비교하여 상대적으로 크기 때문에 축력의 작용폭이 좁아져 마찰영역으로 작용하는 내부 압축응력의 분포영역이 작아지기 때문으로 판단되며, 이는 유한요소해석 결과로도 확인할 수 있었다. 또한, 피로시험 결과 과대공 시험편의 피로균열의 발생점이 표준공 시험편 보다 볼트 구멍 내벽에 가까운 것을 알 수 있어, 피로균열의 발생위치는 고장력 볼트의 도입축력에 의해 모재와 이음판에 형성되는 내부 압축응력의 분포영역과 밀접한 관계가 있음을 알 수 있었다.

야생식물 중독의 임상 양상

옥택근,박찬우,조준휘,천승환,이승용,김성은,최기훈,배지훈,서정열,안희철,안무업,조병렬,김용훈,Ok, Taek-Gun,Park,, Chan-Woo,Cho, Jun-Hwi,Cheon, Seung-Whan,Lee, Seung-Young,Kim,, Sung-Eun,Choi, Ki-Hoon,Bae, Ji-Hoon,Seo, Jeong-Yeul,Ahn, Hee-Cheo 대한임상독성학회 2005 대한임상독성학회지 Vol.3 No.2

Purpose: With the recent boom in 'eating healthy', many adults are interested in dieting to prevent future diseases. However only well trained experts can distinguish between what are edible vegetables and herbs from their poisonous look-alikes. In cases where a patient unknowingly ingests a poisonous herb, is caught off guard by the poisonous side effects that occur because of their lack of knowledge of what they have ingested. This paper will focus on the need to educate the public about the risks involved with ingesting wild vegetables and herbs and study the emergency diagnosis and treatment of poisoned patients that enter the emergency room. Method: This study was done in the spring of 2004 (from March to May) in the Kangwon Young-Seo districts of Korea. 15 subjects used in this study, entered the emergency room showing signs of toxic symptoms. Data was collected by examining subject's records. Additional data was collected by collaborating with physicians in the hospital that diagnosed and treated the subjects. Identifying the poisonous vegetable or herb is the first step to proper diagnosis and treatment. Subjects admitted to the emergency room, underwent a battery of tests: laboratory examination, ECG, radiological exam and etc. Results: The demographics of the study encompassed subjects with the average age of $50{\pm}19$ years old. There were 10 men and 5 women. Common symptoms of this study included; gastrointestinal symptoms such as nausea, vomiting, epigastric pain and so on. In the case of Caltha palustris ingestion, additional symptoms were present; bradycardia and hypotension which lasted for a long time. While cases that ingested Scopolia parviflora had little effect on vital signs but manic episodes lasted for about three days. Veratrum patulum ingestion showed signs of bradycardia and hypotension but contrary to Caltha palustris recovery was shorten by treating with dopamine. However, dizziness, headache and paresthesia of the extremities continued for a long time. Finally Sium ninsi ingestion showed visual disturbance, paresthesia of the extremities, dizziness as their initial symptoms. Conclusion: The risks involved with ingesting wild plants without the proper knowledge can lead to serious side effects and steps need to be taken to educate the public. In addition, all emergency physicians need to have a working knowledge of the symptoms and signs associated with ingesting toxic wild plants and need to treat accordingly.

집중부식배관의 전기방식 설계에 관한 연구

이승용(Seung-Yong Lee),박중익(Chung-Ik Park),이상군(Sang-Gun Lee),박재영(Jae-Young Park),박종일(Jong-Il Park),김우재(Woo-Jae Kim) 대한전기학회 2016 대한전기학회 학술대회 논문집 Vol.2016 No.7

프리스트레스트 콘크리트 가로보의 구조거동에 관한 실험적 연구

이승용 ( Lee Seung-yong ),김경태 ( Kim Kyong-tae ),최영준 ( Choi Young-joon ),우영택 ( Woo Young-taek ),정용휘 ( Jeong Yong-hwi ) 한국구조물진단유지관리공학회 2019 한국구조물진단유지관리공학회 학술발표대회 논문집 Vol.23 No.2

강아치교는 경간거리가 비교적 길고 거더 높이에 제약이 있는 가설조건에 자주 적용되는 교량형식이지만, 강아치교에서 강재 바닥틀(가로보, 세로보)이 차지하는 강중은 50% 이상으로 초기건설비용 증가의 원인으로 작용한다. 강아치교의 정체성은 살리면서 경제성 제고를 위해 강재 바닥틀을 콘크리트 부재로 대체시 획기적인 경제성 개선이 가능하다. 본 연구는 PSC 가로보의 아치교 적용을 위하여 PSC 가로보 시험체를 대상으로 정적시험 및 피로시험을 실시하고, 정적 구조 성능 및 피로성능을 분석함으로써 PSC 가로보의 구조안전성 및 사용성을 평가하였다. 그 결과 콘크리트 구조체, PS강선, 주철근, 브래킷, 연결부 모두 안정적인 구조거동을 보이고 있으며, 충분한 피로수명을 확보하고 있는 것을 확인하였다.

신재생에너지연료와 석탄 혼소에 따른 플라이 애시의 특성 변화

이승용(Lee, Seung Yong),강국희(Kang Kook Hee),이원준(Lee Won Jun),이승헌(Lee, Seung Hun),문영범(Mun Young Bum) 한국콘크리트학회 2018 한국콘크리트학회 학술대회 논문집 Vol.30 No.1

문화관광 축제 프로그램 및 서비스 요인이 참가자 만족과 행동의도에 미치는 영향-익산국제돌문화프로젝트를 중심으로-

이승용 ( Seung-young Lee ) 한국고등직업교육학회 2009 한국고등직업교육학회논문집 Vol.10 No.4

This study attempts to identify the level of program and service quality, visitors' satisfaction, and their behavioral intentions in 2008 IKSAN INTERNATIONAL STONE CULTURE PROJECT. Seven programs and service quality factors of cultural tourism festival including staff service, exhibitions, symposium of sculptures, place environment, hall environment, design and goods on fair were derived from factor analysis. One of the major research findings is that, the visitors' satisfaction of programs and service factors on culture tourism festival have positive correlation with both overall satisfaction and behaviour intentions. In addition, overall satisfaction and behaviour intention were also found to be positively correlated. The result of this studies implies that the host of cultural tourism festival must put a great emphasis on organizing that program, particularly participating program. This will lead the cultural tourism festival to a great success and ultimately bring positive impact.