• Journal of the Korean Wood Science and Technology
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• v.30 no.2
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• pp.172-179
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• 2002

In this study, two materials treated with a flame retardant were examined for their fire resistance. The first, MDF (medium density fiberboard) was overlaid by an oak sliced veneer, which was either treated by soaking in a 6wt.% solution of flame retardant chemicals (pentabromine-chlorinated paraffin) or non-treated and then was coated with either a flame retardant polyurethane coating or with a common polyurethane coating. The second material, Pinus koraiensis penal was either treated by a spray treatment using a flame retardant solution or non-treated and then was coated with either a flame retardant polyurethane coating or with a common polyurethane coating. Pentabromine-chorinated paraffin chemicals were added (6 part of urethane resin) as the flame retardant chemicals in the polyurethane coatings. In the fire resistance test, the th𝜃(℃·min) decreased with the flame retardant treatment or/and the flame retardant coatings, compared to the untreated sample Weight loss (%) decreased with the flame retardant treatment or/and the flame retardant coatings. The ignition time (sec.) increased and the residual flame time (sec.) decreased with the flame retardant treatment or/and flame retardant coatings. Therefore, the flame retardant treatment or/and flame retardant polyurethane coatings have excellent incombustibility.

• Bulletin of Food Technology
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• v.25 no.2
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• pp.116-128
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• 2012

식품동결에 의한 품질손상에 있어 크게 영향을 미치는 인자 중의 하나가 체적변화에 의한 조직 파괴이므로 식육 및 과채류의 냉동시 내부압력에 따른 조직파괴를 방지하기 위한 기초연구로 다양한 동결방법에 따른 내부압력 변화에 대하여 조사한 결과, 급속 및 완만동결시 우육의 내부압력 변화 경향은 동결 직전에 급격히 상승한 후 동결 초기부터 최대빙결정생성대를 통과하는 동안은 급격히 감소하다가 다시 온도가 내려감에 따라 압력변화는 증가와 감소를 반복하여 상승하는 경향을 보여 주었고, 동결시의 내부압력 크기는 약 8~10 psig 수준이며, 내부압력의 변화 경향은 정지공기식보다 침지식에서 약 1 psig 정도 크게 나타났다. 냉동냉장시에 일어나는 내부압력의 상하변화는 돈육의 품온차가 ${\pm}1^{\circ}C$일 때, 시료중량에 따라 1.84~2.32 psig 정도의 내부압력 차가 반복적으로 발생됨을 알 수 있었다. 또한, 돈육의 해동시 내부압력은 해동 개시 후 급격히 상승하여 5분 이내에 최고압력에 도달한 이후에는 서서히 하강하였으며, 해동시에 발생한 내부압력의 값은 동결시의 내부압력 값보다도 대부분 크게 나타났다. 또한, 균온처리한 우육의 동결시 내부압력 값은 약 1~4 psig 수준으로 균온처리하지 않은 우육에 비하여 매우 적게 나타났으며, 동결소요시간도 약 10~20% 정도 짧게 나타났다. 그리고 균온처리 및 다양한 동결방법에 따른 동결식육의 조직과 냉동냉장 중의 품질변화를 비교 검토한 결과, 동결방법에 따른 드립손실율은 우육의 경우 정지공기식으로 처리한 시료는 타 처리구에 비해 계속 높게 나타났으며, 돈육은 우육에 비해 상대적으로 드립손실량이 적게 나타났으나 송풍식으로 처리한 시료에서 저장 40일째, 7.39%로 가장 높게 나타났다. 동결 우육 및 돈육의 pH변화는 뚜렷한 차이를 나타내지 않았으며, VBN 및 TBA값에 있어서는 균온 처리한 시료가 완만 및 급속동결 처리한 타 시료에 비해 저장 200일까지 가장 변화가 없었다. 동결저장온도의 상하변동에 있어서는 온도변동 횟수가 증가할수록 pH 및 수분함량은 뚜렷한 변화가 없었으나 드립손실율, VBN 및 TBA값은 온도 변동횟수가 증가할수록 서서히 증가하는 경향을 보여 주었다.

• Food Science and Preservation
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• v.7 no.4
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• pp.343-348
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• 2000

Characteristics of major suing Chinese cabbage cultivars in Korea, Norangbom(Nor), Gonaenggiyeurum(Gon), Maereuk (Mae) and Housekumgarak (Hou), and their qualities of Kimchies were investigated. Mean weight of the cabbages was in the range of 1.39∼2.40 kg, and was higher Gon, Mae, Nor, Hou in order. Leaves number was Gon 45, Nor 56, Mae 59 and Hou 56 pieces. Sensory taste of raw Chinese cabbage was best in Nor. Decreasing rate of gumminess and chewiness by salting was the highest in Gon and the lowest in Nor. fermentation of Gon and Nor-Kimchi were faster than Mae and Hou-Kimchi. Amount of gas formation during fermentation was the highest in Mae-Kimchi and lowest in Nor-Kimchi. Decreasing rate of AIS was the fastest in Mae-Kimchi and the latest in Hou-Kimchi. Hardness and gumminess of Kimchi fermented for 21 days were to be ordered Mae-Kimchi, Hou-kimchi, Gon-Kimchi and Nor-Kimchi. Overall acceptability by the sensory test was good in Nor- and Hou-Kimchi.

• Journal of the Korean Wood Science and Technology
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• v.30 no.2
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• pp.115-120
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• 2002

Woodceramics are new porous carbon materials obtained by burning wood or woody materials impregnated with thermosetting resin in a vacuum furnace. In this paper, the change of dimensions and bending strength of woodceramics which were made from medium density fiberboard have been investigated to examination the possibility of utilization as a woodceramics materials. 1) An increasing rate of dimension in impregnated board increased with increasing resin impregnation rate. And increasing rate of thickness was higher than that of length. 2) When the resin impregnation rate increased, the bending strength of impregnated board had a tendency to increase. 3) The rates of weight loss, length and thickness reduction of woodceramics showed a slight increase with increased burning temperature. 4) The density of woodceramics showed a increase from at 500℃ till at 800℃ with increasing burning temperature but decrease at 1,000℃ 5) When the burning temperature increased, the bending strength of woodceramics had a tendency to increase.

• Journal of Bio-Environment Control
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• v.9 no.4
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• pp.230-236
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• 2000

For extension of storability, onion bulbs produced in Cheju Island were exposed to ${\gamma}$-ray irradiation at a dosage of 0, 3, or 6Krad and stored in a natural cavern, or in low (2$^{\circ}C$) or ambient temperature storage condition. Sprouting began from approximately five months in storage, regardless of storage condition, and increased as the storage period increased. From early August, sprouting as high as 50% occurred in the natural storage cavern, and 20% in ambient temperature storage when bulbs were treated with 0 krad ${\gamma}$-ray. However, bulbs treated with 3 or 6krad ${\gamma}$-ray did not any sprouting until six months in storage. No significant weight loss was observed in all treatments until sprouting occurred from 40 days after the initiation of storage. Weight loss, however, increased remarkably after 40 days in storage, indicating that it was closely related to sprouting during storage. Bulbs stored at 2$^{\circ}C$ showed 5~10% rot, but were still edible. Percent rot reached to as high as 50% in bulbs unirradiated and stored at ambient temperatures after seven months, while it in irradiated bulbs reached to 5, 33, and 30% at 2$^{\circ}C$, in a natural cavern, and ambient temperatures, respectively. Sugar contents slightly increased in irradiated bulbs in the later storage period under ambient temperatures, while sugar contents in irradiated bulbs in the later storage period under ambient temperatures, while sugar contents in Allium vegetables generally decrease in later storage if unirradiated. Sulfur content slightly increased in irradiated bulbs in the early storage period and decreased gradually in all treatments in the later storage stage.

• The Journal of Engineering Geology
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• v.10 no.1
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• pp.1-12
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• 2000

Heaving of road and subsidence of slope took place at the Wiri region of the local highway 999 in Gyeongsangbukdo, Korea after heavy rain in the next year of construction. Although the state government had performed remedial treatments by reducing the angle and the height of the slope, deformation had never stopped. Therefore, we have preformed the analysis of deformation and stabilityof the slope. Study area consists of the Cretaceous shale, siltstone and sandstone and two faults are found. The major deformation occurred by sliding of rock mass along faults after heavy rain because not only thepore pressure at the fault plane and the unit weight of sliding mass increased, but did the shearstrength of saturated fault clay become very low. The decrease in shear strength of saturated fault clayis the major factor among the reasons for deformation. Numerical simulations using limit equilibriummodel, finite difference model and finite element model were performed for eight cross sections.Although safety factors are above 1.7 during the dry season, they become below 1.0 when groundwaterlevel raises to surface. The maximum displacement is about 15-3Ocm. However, safety factors increasedto above 2.4 and the maximum displacement is below 2.08cm after remedial treatment, Indicating thatthe slope becomes stable.

• Food Science and Preservation
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• v.23 no.6
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• pp.772-777
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• 2016

Activity of the noncontacted low temperature atmospheric pressure surface discharged plasma (LASDP) converts stable gas to ionized gas known as discharge or plasma. This ionized gas exhibits the antimicrobial activity. We examined the effects of 3 different storage treatments for 80 days on 'Setoka' : ambient storage (AS), low-tempperature storage (LTS), and low-temperature atmospheric pressure plasma+low-tempperature storage (PLTS). Total soluble solids showed no the significant differences between the 3 treatments. Acidity gradually decreased, and was 0.5% under AS after 30 days of storage. Fruit firmness increased by a few percent until 40 days of storage. Weight loss in AS was higher than for other treatments. After 80 days of storage, the decay ratio was significantly low in PLTS treatment: (AS, 50.5%; LTS, 5.6%; PLTS, 1.9%). In AS treatment, 73% of the rotten fruits were infected particularly with green and blue mold; however, only 1% of the rotten fruits were infected in case of PLTS treatment. In conclusion, LASDP treatment can prevent postharvest decay caused by fungi and is an efficacious alternative extending the shelf-life of citrus fruits.

• Journal of Marine Life Science
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• v.5 no.2
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• pp.51-57
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• 2020

Disinfection and maintenance of rearing water in aquaculture is an essential element for the prevention of fish diseases. This is especially important in recirculating aquaculture systems (RAS) in which fish are reared at high density using recycled water. In this study, tilapia was reared in two different RAS (one with plasma generator - PW system, another without plasma generator - No PW system). In plasma treated group, UVT% of water was improved clearly, and the number of heterotrophic bacteria decreased significantly after 40 days. Total weight gain of tilapia in PW system was significantly higher, and other growth indicators were also relatively higher although not statistically significant. In addition, the fish in PW system had a 100% survival rate, and there were no histological differences between fish from both systems. Fish did not seem to be affected by the toxicity of ROS. In conclusion, it is expected that plasma water can effectively deactivate fish pathogens and improve the quality of rearing water.

• Korean Journal of Plant Resources
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• v.9 no.1
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• pp.1-9
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• 1996

The effects of multipore spawn inoculation of Lentinus edodes on the mycelial growth stage and on the quantitative and qualitative yields of fruit-bodies for 5 years were investigated at natural environmental conditions. The spawn inoculation quantity did not affect the mycelial rooting at a range of 3.0kg-6.0kg per $m^3$ of bed-logs while the increase of spawn quantity by multipore inoculation increased the mycelial growth and the inner erosion of bed-logs, resulting in the increased yields of total fruit-bodies of L. edodes per $m^3$ of bed-logs for 5 years but resulting in the shortened major production period of fruit-bodies to the the first three years. Major production of fruit-bodies occurred during May-June and August-September, which was not affected by the spawn inoculation quantity. No significant differences in dry weight of a fruit-body were observed as increasing the spawn quantity by multipore inoculation; however the heaviest dry weight of a fruit-body was 1.63g at the spawn inoculation of 4.0kg per $m^3$/TEX> of bed-logs.

• Food Science and Preservation
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• v.8 no.1
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• pp.9-15
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• 2001

The effects of water soaking and gamma irradiation on the storage quality of chestnuts (Castanea crenata) were investigated. Chestnuts weirs soaked in water for 48 hrs at room temperature, irradiated at 0, 0.15, 0.25 and 0.35 kGy of $\^$60/Co gamma ray, and then stored at 0$\^{C}$ and 95$\pm$2% RH for 9 months. Spouting was observed at the end of storage only in chestnuts that were soaked and irradiated at below 0.25 kGy. Rotting was found from the early stage of storage in all pre-treatment conditions, but the rotting rate of soaked chestnuts was higher twice than unsoaked ones after 9 months of storage. Weight loss was lower in soaked than unseated samples regardless of irradiation dose. Loss of flesh firmness was appreciably retarded as irradiation dose increased. Total sugar content decreased slowly in irradiated samples at the later periods of storage. Gamma irradiation resulted in the decrease of vitamin C content immediately after treatment, but retarded its loss rate during storage. Soluble tannin content was not affected by gamma irradiation at scout inhibition doses.