• 한국안전학회지
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• 제23권5호
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• pp.67-72
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• 2008

The lower flash points for the flammable binary systems, 2-propanol+formic acid and 2-propanol+n-butyric acid, were measured by Cleveland open cup tester. The optimization method using van Laar equation and the Raoult's law were used to estimate the lower flash points and were compared with experimentally-derived data. The calculated values based on the optimization method were found to be better than those based on the Raoult's law.

• KIEAE Journal
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• 제7권6호
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• pp.37-43
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• 2007

Discomfort glare is an important factor influencing appraisal for lighting environment. Unified Glare Rating (UGR) which has been proposed by CIE is one of the formula for evaluating discomfort glare. Position index is an important factor in the UGR formula. Position index was proposed by Guth in 1949. It has been used until present limiting upper visual field. Lower visual field has different sensation of brightness in comparing with upper visual field. Therefore, it is necessary to propose position index about lower visual field. The objective of this study is to investigate the brightness sensation in upper and lower visual field. First, the visual field was measured on the self-made Glare Tester. Second, luminance of the Borderline between Comfort and Discomfort (BCD) was measured on the glare Tester. Circular sources of brightness were located at various angular distances from the line of vision along five meridians, $0^{\circ}$, $45{\circ}$, $90{\circ}$, $-45{\circ}$, $-90{\circ}$. The size of the glare source is 0.0011sr. The luminance of the surrounding field, which extended over the entire visual field, was maintained $34ccd/m^2$. Ten subjects aged from 25 to 29 were participated in the experiment. The results show that the luminance of BCD on the line of vision is $4337cd/m^2$ and the glare sensation of the lower visual field is more sensitive than the upper visual field.

• 한국산업융합학회 논문집
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• 제4권4호
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• pp.379-386
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• 2001

The lower toughness or brittle materials for mechanical test lead to the additional requirement that applied displacements be controlled with high resolution. Biaxial tension and shear tester using stepper motor with harmonic driver is shown. The device had to be high resolution so that the crack initiation process of slow extension and steady growth could be examined, Grip plates were connected to a linear bearing and actuator. The actuators consisted of stepper motors with harmonic driver connected to pre-loaded ball screw and nut assemblies. The encoders and motor controllers were connected to a personal computer so that arbitrary displacements histories could he prescribed in normal and tangential directions. The linear bearings were used to react loads perpendicular to their axes while allowing low friction, parallel movement of the attached grips. Load cells measured the reactions normal and tangential. the loads measured the reactions were recorded by the computer.

• 한국안전학회지
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• 제22권3호
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• pp.22-27
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• 2007

The knowledge of the flash point of the various liquid substances is required because of process safety and control in industrial fire protection. The epoxy resin is one of versatile resins that has wide selection of using curing agents and additives to achieve various applications such as coatings, adhesives, interior materials, reinforced plastics and electrical insulation. In this study, the lower flash points for p-xylene+epoxy resin, o-xylene+epoxy resin and n-butanol+epoxy resin systems were measured by using Pensky-Martens closed cup tester. The lower flash points for p-xylene+epoxy resin, o-xylene+epoxy resin and n-butanol+epoxy resin systems rapidly increased 80wt%, 90wt% and 95wt% of epoxy resin concentration, respectively. This results serve as a guide to estimate flash point of any epoxy resin solution.

• 한국가스학회지
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• 제16권5호
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• pp.41-46
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• 2012

인화점은 공기 속 가연성 증기의 농도가 연소하한계(lower flammability limit)에 도달할 때의 최저 온도이며, 산업현장에서 사용하는 물질들의 화재와 폭발의 위험성을 결정하는 중요한 물성치이다. 단일 성분의 인화점 정보는 여러 문헌에서 얻을 수 있으나, 이성분계 혼합물의 인화점은 충분히 제공되어 있지 않다. 본 연구에서는 tert-pentanol+n-decanel 계의 인화점을 Tag 개방식 장치를 이용하여 측정하였다. 실험값은 Raoult의 법칙과, Wilson 식과 NRTL 식을 활용한 최적화 기법에 의해 계산된 값들과 비교되었다. 최적화 기법에 의한 계산값이 Rauolt의 법칙에 의한 계산값 보다 실험값에 더욱 근접하였다.

• 한국축산시설환경학회지
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• 제7권2호
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• pp.119-126
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• 2001

For the odor test, it was chosen the conventional spreader, the hose spreader, and its combination with disk harrow and spring harrow as a slurry spreader. By the odor tester (Kalmor-$\sum$) with dairy slurry, the conventional spreader has the average $\sum$ value of 270, which means that one fells substantial odor and torment. In the cases of hose spreader and its combination with disk harrow, $\sum$ value was 217 and 182 respectively, which means a normal person does not smell any odor. Spreading the swine slurry with a conventional spreader shows $\sum$ value of 440, which means one feels unpleasant. The hose spreader shows $\sum$ value of 258, which lies in the limit one feels some odor and torment. Its combination with disk harrow has $\sum$ value 184, which means that a normal person can not smell any more. For the conventional spreader, the odor intensity indices from air dilution sensual test and 3 point odor bag as a sensual test were 66.9 and 35.4 respectively. On the other hand, the indices were 9.65 and 11.10 by hose spreader and its combination with disk harrow, which were lower than that of the regulation for industry. Therefore, the developed hose spreader showed an excellent effect on decreasing odor. The correlation between the results from odor tester and 3 point odor bag has shown 0.997 by swine slurry.

• 한국화재소방학회논문지
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• 제25권2호
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• pp.114-119
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• 2011

폭발한계와 인화점은 가연성물질의 화재 및 폭발의 위험성을 결정하는데 중요한 연소특성치이다. 본 연구에서는 산류와 케톤류의 폭발상한계를 예측하기 위해서, 평형상태에서 인화점을 측정하는 Setaflash 밀폐식 장치(ASTM D3278)를 사용하여 이들의 상부인화점을 측정하였다. 측정된 상부인화점을 이용하여 Antoine 식에 의한 계산된 폭발상한계는 기존의 문헌값들보다 약간 낮게 나타났다. 본 연구에서 제시한 실험 및 예측 방법을 이용하여 다른 가연성물질의 폭발상한계 예측이 가능해 졌다.

• Elastomers and Composites
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• 제58권3호
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• pp.103-111
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• 2023

The abrasion resistances of silica-filled styrene-butadiene rubber (SBR) compounds prepared with and without dicyclopentadiene resin (SBR-R and SBR-0, respectively) were studied using four different abrasion testers, namely cut and chip (CC), Lambourn, DIN, and laboratory abrasion tester (LAT100). The effect of the resin on the abrasion behavior was elucidated by analyzing the morphologies and size distributions of wear particles. All the wear particles had rough surfaces, but those obtained in the Lambourn abrasion test exhibited relatively smooth surfaces. The size distributions of the wear particles showed different trends depending on the abrasion tester and the rubber compound; however, most of the wear particles were larger than 1000 ㎛. The SBR-R sample showed a wide range of particle sizes (from 63 ㎛) in the LAT100 abrasion test and majority of the wear particles were 500-1000 ㎛, whereas the SBR-0 sample had the most distribution of larger than 1000 ㎛. The abrasion rates of SBR-0 sample were lower than those of the SBR-R sample for the CC and LAT100 abrasion tests, but the Lambourn abrasion test result showed the opposite trend. Addition of the resin influenced the abrasion behavior, however the effect varied depending on the type of abrasion tests.

• 한국화재소방학회논문지
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• 제29권5호
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• pp.1-6
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• 2015

인화점은 화재 및 액체의 폭발 위험의 가능성을 결정하는 데 사용되는 가장 중요한 물리적 특성이고, 산업공정에서 안정성 평가시 중요한 연소특성 가운데 하나이다. 따라서 본 연구는 4류 위험물 중 알코올계 혼합물인 {methanol + 1-butanol}, {ethanol + 1-butanol} 그리고 {2-propanol + 1-butanol} 이성분계 101.3 kPa에서 최소인화점을 SETA closed cup flash point tester를 이용하여 측정하였다. 각 이성분계에 대하여 Wilson, NRTL 및 UNIQUAC 파라미터를 이용하여 혼합물에 대한 인화점 예측하고 실험 결과와 비교하였다. 비교결과 모든 예측값과 실험값은 유사한 값을 보였고 편차가 1.14 K 이내의 결과를 보였다.

• 한국화재소방학회논문지
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• 제24권2호
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• pp.76-81
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• 2010

톨루엔의 안전한 취급을 위해서 $25^{\circ}C$에서 폭발한계와 폭발한계 온도의존성을 고찰하였다. 또한 인화점과 최소발화온도를 측정하였다. 공정의 안전을 위해서 톨루엔의 폭발하한계는 1.13vol%, 상한계는 7.9vol%를 추천한다. 유통법에 의한 하부인화점은 $5^{\circ}C$, 상부인화점은 $40^{\circ}C$로 측정되었으며, Setaflash 장치에 의한 상부인화점은 $41.5^{\circ}C$로 측정되었다. ASTM E659-78 장치에 최소자연발화온도는 $547^{\circ}C$로 측정되었다. 그리고 톨루엔의 새로운 폭발한계 온도의존식을 제시하였으며, 제시한 온도의존식은 문헌값과 일치하였다.