• 한국식품과학회지
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• 제45권1호
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• pp.120-125
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• 2013

유리섬유를 이용하여 B. cereus의 biofilm 형성 조건을 확인한 결과 3시간 이후부터 부착하여 48시간에 biofilm이 많이 형성된 것을 확인하였다. 그리고 biofilm 형성 B. cereus의 제어를 위해 에탄올, NaCl, 유기산을 각각 단독으로 처리하였을 때 1% 젖산, 아세트산, 구연산을 30분 처리하였을 때 약 5-6 log CFU/g-glass wool 수준 감소하여 가장 좋은 효과를 나타냈다. 또한, 20% 에탄올과 각각의 1% 유기산, 20% 에탄올과 10% NaCl의 두 가지를 혼합 처리의 경우 단독으로 처리했을 때보다 저감화 효과가 우수했으며, 20% 에탄올과 10% NaCl 및 각각의 1% 유기산을 1-5분 동안 혼합 처리 했을 때 약 7-8 log CFU/g-glass wool 수준이 감소하여 biofilm 형성 B. cereus의 제어에 가장 효과적이었다. 따라서 본 연구 결과를 통해 유기산, 에탄올, NaCl 복합 처리 방법을 사용하여 biofilm 형성 B. cereus의 저감화를 효과적으로 할 수 있을 것으로 판단된다.

• 한국산업보건학회지
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• 제9권2호
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• pp.158-166
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• 1999

The purpose of this study was to investigate the correlation between airborne total dust and man-made mineral fibers (MMMF), and to estimate total dust concentration to maintain below the American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV$^{(R)}$) for the MMMF. The regression coefficients between airborne total dust concentrations and fiber concentrations determined in the industries producing glass fibers, rock wool. refractory ceramic and continuous filament glass fibers products were 0.41, 0.42, 0.20 and 0.19, respectively. The size characteristics of fibers as well as the amounts of contaminated non-fibrous dusts could affect the correlation intensities. When total dust and fiber exposure data were compared with the occupational exposure limits, there was a large gap between two evaluation results. The regression coefficient between total dust and fiber data was increased ($r^2=0.88$) in the process of insulation installation generating in the higher levels of glass or rock wool fibers. In this case, an estimated total dust concentration of glass wool or rock wool fibers complying with the ACGIH TLV (1 f/cc) was $1.7mg/m^3$. In conclusion, the total dust and fibers concentrations was highly correlated at the higher exposure levels so that total dust-monitoring data could be used to control simply and economically and to estimate worker's exposure to fibers.

• 한국산업보건학회지
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• 제16권1호
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• pp.11-16
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• 2006

There are many counting rules for analyzing man-made mineral fibers. The representatives are the NIOSH Method 7400 A and B counting rules. The two rules have different rules of length-to-width ratio(aspect ratio) and diameter. The A rule counts only fibers $>5{\mu}m$ in length, and only fibers with aspect ratio >3:1. The B rule counts only ends of fibers $>5{\mu}m$ in length and $<3{\mu}m$ in diameter, and only fibers with aspect ratio ${\geq}5:1$. The A counting rule had been used before the B counting rule was introduced. The purpose of this study is to compare the A and B counting rules for airborne fibers from various man-made mineral fibers(glass wool fibers, rock wool fibers, refractory ceramic fibers, and continuous filament glass fibers) industries. There were significantly differences between the paired counts of A and B rules in all types of fibers(p<0.05). A rule counts/B rule counts(A/B ratios) were 1.52 for glass fibers, 1.53 for rock wool fibers, 1.19 for RCF, and 1.82 for continuous filament glass fibers. The counting results by A and B counting rules were highly correlated in glass wool fibers, rock wool fibers and refractory ceramic fibers(RCF) samples (r=0.96 for all types of fibers) except continuous filament glass fibers(r=0.82). Regression equations to correct for the differences between counting rules were presented in this paper.

• 폴리머
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• 제25권3호
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• pp.427-434
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• 2001

폴리에스터를 이용하여 새로운 자동차용 흡음재를 개발하였다. 흡음의 효과를 최대화시키기 위하여 PET 섬유의 크기를 3과 15 denier로 달리하여 3개의 층으로 제작하였으며, 이때 각층의 중량을 조절하여 밀도를 변화시켰다(895~1790 g/$cm^2$). 또한 PET흡음재의 상업성을 알아보기 위하여 시판하고 있는 glass wool로 제조된 흡음재와 비교 분석하였다. 새로운 PET흡음재는 시판되고 있는 glass wool 흡음재보다 저주파와 고주파대역 모두에서 더 우수한 흡음성능을 보여주었다. 또한 PET흡음재의 밀도와 두께가 흡음성능에 중요한 영향이 있으며, 최적화된 PET흡음재는 시판되고 있는 흡음재와 비교하여 NRC (noise reduction coefficient)가 약 22-39% 향상되었다. 따라서 PET는 성능은 물론이고 환경과 재활용혈에서 glass wool을 충분히 대체할 수 있으리라 생각한다.

• Clinical and Experimental Reproductive Medicine
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• 제15권2호
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• pp.149-155
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• 1988

To increase fertilization rate in vitro, separation of viable spermatozoa from the seminal plasma and its other components may be a useful procedure. Ejaculates from healthy men, whose semen analysis findings were normal in 19, and abnormal in 10, were filtered using the glass-wool filtration technique to yield a concentrated, viable sperm samples for IVF, and the usefulness and safety of this method were evaluated. The recovery rate of motile sperm in abnormal groups was 46.2% and 54.5% in normal group. The % motility was increased significantly compared with original sample after filtration, and the grade motility was improved, too. The sperm population with normal morphology was also increased significantly in both group. Using transmission electron microscopy, the ultrastructural integrity of acrosomal segment was examined in order to evaluate the potentially hazardous effect of glass-wool filtration to sperm head, however, sperm population with normal ultrastructure was increased compared with that of original ejaculate after separation. The filtered sperm was then processed for IVF, as the fertilizing capacity is the ultimate parameter of the sperm function. In abnormal group, the fertilization rate(41.5 %) and the ET rate per stimulated cycle were much lower than that of mormal group(69.6%). However, the cleavage rate and the number of embryos transfered per ET cycle were comparable with those of nomal group. The results suggest that the glass-wool filtration of sperm, particularly in oligo-asthenozoospsrmia, may be useful and safe method in the preparation of sperm for IVF.

• 한국식품과학회지
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• 제38권1호
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• pp.135-139
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• 2006

세균이 외부stress에 대한 자가저항으로 biofilm형성을 하는 것은 식품 뿐만아니라 식품기기등의 세척, 소독등의 식품안전 확보에 많은 어려움을 주게 된다. 본 연구에서는 glass wool과 mlcrotiter plate assay를 이용하여 주요 식중독 세균인 Salmonella, E. coli, B. cereus, S. aureus를 여러가지 식품보존하에서 상해와 biofilm형성 정도를 비교하였다. 이들 세균은 외부의 stress없는 조건하에서도 상해를 받지 않았고 모두 biofilm이 형성되어 glass wool에 부착되었다. Microtiter plate assay에서의 상해별 biofilm형성은 acid stress에서 10%이내의 상해를 받은 E. coli와 약 40%의 상해를 받은 S. aureus에서 높게 나타났다. $4^{\circ}C$의 cold temperature에서는 30-50% 상해를 나타낸 B. cereus와 E. coli가 높은 biofilm 형성을 보였고 cold starvation에서는 다른 stress에 비해 전체적으로 biofilm형성도가 낮은 값으로 측정되었다. 그리고 6% sodium chlorine solution에서 30-55%의 상해를 입은 Salmonella가 높은 biofilm 형성도를 보였다. 그러나 같은 종의 식중독 세균이라도 외부의 stress 대하여 다양한 정도의 biofilm을 생성하는 것으로 보인다. 따라서 식품으로부터 이들 식중독 세균을 제어하기 위해서는 대상식품의 보존환경에 따른 biofilm 형성특성을 고려해야 할 것으로 사료된다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 가을 학술발표논문집(II)
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• pp.239-244
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• 1998

Fusion temperature of fly ash was determined with wasted glass wool and borax using ash fusion determinator, 0.5wt% of bentonite and water glass used as binder, 50wt% of wasted glass wool added to fly ash, fusion temperature of fly ash was 1, 156$^{\circ}C$. Pellet was prepared, and then sintered at 1, 00$0^{\circ}C$ and 1, 10$0^{\circ}C$. Water-absorption rate, specific gravity, porosity and pore structure of sintering aggregate was determined.

• 한국산업보건학회지
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• 제22권2호
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• pp.134-139
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• 2012

Objectives: This study was conducted to study the analytical variability of A & B counting rules in counting using a phase contrast microscope airborne fibers collected on filters in man-made mineral or vitreous fibers (MMMFs) industries. Methods: Fibers in filters were counted using A & B rules of NIOSH Method 7400. Intra-counter and inter-counter variations by fiber type and density were obtained. The types of MMMFs analyzed were glass wool fiber, rock wool fiber, slag wool fiber, and refractory ceramic fibers. The densities of fibers classified were <20 $fibers/mm^2,$ 20 - <50 $fibers/mm^2$, 50 - <100 $fibers/mm^2,$ and ${\geq}100$ $fibers/mm^2,$ respectively. Results: Intra-counter relative standard deviations by rule A were 0.084, 0.102, 0.071 for glass wool fibers, rock wool fibers and refractory ceramic fibers, and those by rule B were 0.139, 0.120 and 0.142, respectively. Inter-counter relative standard deviations by rule A were 0.281, 0.296, 0.180 for glass wool fibers, rock wool fibers and refractory ceramic fibers, and those by rule B were 0.396, 0.337 and 0.238, respectively. Conclusions: Intra-counter variation was not different significantly among fiber types (p>0.05), but B rule variation for ceramic fibers approximately 2 times greater than corresponding A rule estimates, and intra-counter and inter-counter variations were higher in the low fiber density.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 추계학술대회논문집
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• pp.923-927
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• 2003

The aim of this study is to investigate the characteristics and quantity of the noise reduction by pipe material, wrapped pipe with glass wool and installed pipe height The characteristics of noise emission from drain-pipes is as follows. The noise reduction pipe in PVC can reduce noise levels in 7-10㏈ and the cast-iron pipe can reduce in 14㏈compared with the normal PVC pipe. In these days, the glass wool was used for preventing the burst and the noise reduction. But the glass wool for wrapping pipe is not effective to the noise reduction. The characteristics of noise emission from various installed pipe height were measured As the ceiling space of the remodeled building was raised, the noise level was troubled by increasing of the vertical pipe length.

• 한국임상수의학회지
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• 제24권4호
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• pp.577-583
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• 2007

It is important to obtain semen with good quality for efficient fertilization and pregnancy. To obtain these semen, various methods have been developed but most of these methods are time consuming and require costly equipment. Therefore, the objective of this research is to investigate the usability of column filtration system as quick and simple method to get sperm with better quality. Ejaculates were obtained from 5 dogs and analyzed with basic quality parameters before each filtration. Sperm concentration was adjusted to $5{\times}10^7/ml$ after dilution. The experimental groups were divided into non-filtered group(control) and filtered groups(glass wool, Sephadex 5% and Sephadex 20%). Ejaculates were filtered through each filter system and assessed by recovery rate of sperm, motility, normal morphology, CFDA/PI stain and plasma membrane integrity(hypo-osmotic swelling test, HOST). The lowest recovery rate of spermatozoa was recorded in glass wool filtration group, followed by 20% Sephadex filtration group(p<0.05). There was no significant difference between control(non-filtered) and 5% Sephadex filtration poop. Also, there was no significant difference of sperm motility assessed under light microscope among experimental groups. Morphological normality of canine spermatozoa was the highest in the glass wool filtration group and the lowest in the 5% Sephadex filtration group with no significant differences versus 20% Sephadex filtration and control group, respectively(p<0.05). Viability of canine sperm assessed by CFCA/PI staining was the highest in the glass wool filtration poop with no significant difference versus the control group, and the lowest in the 20% Sephadex filtration group with no significant difference versus 5% Sephadex filtration group, respectively(p<0.05). HOS values of canine sperm was the highest in the 20% Sephadex filtration group with no significant difference versus 5% Sephadex filtration group, and the lowest in the control poop with no significant difference versus glass wool filtration group, respectively(p<0.05). Therefore, these results indicated that filtration treatment for extended canine sperm would be useful method to get sperm with better quality by trapping the damaged sperm, consequently filter would be physical barrier against injured or immotile sperm.