• International Journal of Highway Engineering
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• v.7 no.2 s.24
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• pp.87-95
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• 2005

To prevent the lowering of structural capability due to freezing and thawing in cold winter, numerous researches on frost heaving have been performed. As the result, the freezing index contour map of the Korea peninsula has been made for the design of the anti-freezing layer of pavements. However, the validity of the anti-freezing layer needs to be evaluated because systematic investigations on the variation of freezing depth with the thickness and material types of pavement layers and the configuration of the ground have been rarely performed. The freezing index of the Korea Highway Corporation test road site was calculated and the freezing depths of the concrete and asphalt pavements of the test road were investigated using the ambient and pavement temperature and water content. In addition, the investigated freezing depths were compared to the values estimated by existing freezing depth models. This is the preliminary study on the freezing-related data measured at the test road. The results with higher reliability will be produced by the long-term accumulation of the data and the analysis on it.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.33 no.7
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• pp.9-20
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• 2004

식품 냉동은 식품에서 열을 빼앗아 식품내의 수분을 액체에서 고체로 상변화시키는 방법 즉, 식품의 온도를 저하시켜 조직내의 자유수를 병결정화 함으로써 미생물 성장과 효소 활성의 억제로 식품의 품질저하를 최대한 방지하는 데 목적을 지닌 품질보존의 수단으로 식품의 장기 보존을 위한 가장 안전한 방법 중의 하나로 알려져 있다. 이와같이 동결식품이 정확히 처리되었으면 식품 본래의 향미, 색, 조직감 및 영양가가 신선상태 그대로 유지되어야 할 것이다. 그러나 식육의 경우 냉동냉장시 드립발생, 단백질 변성 및 지방산화 등을 초래함으로써 품질이 저하하게 된다. 특히, 식육의 변성과 연관된 생화학적 반응은 -2$0^{\circ}C$ 이상의 동결온도에서도 액상으로 잔존하는 식육내에 있는 수분 때문에 일시적으로 정지되거나 감소되지만 저장기간의 경과에 따라 점차적으로 진행이 지속된다. (중략)

• Journal of the Korea Concrete Institute
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• v.15 no.1
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• pp.43-51
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• 2003

Recently, to consider financial and constructive aspect usage of Admixture such as Blast-Furnace Slag and Fly-Ash, are increased. Also the use of cold-weather-concrete is increased. Blast-Furnace Slag, a by-product of steel industry, have many advantage to reduce the heat of hydration, increase in ultimate strength and etc. But it also reduces early-age strength, so it is prevented from using of Blast-Furnace Slag at cold-weather-concrete. In this study, for the purpose of increasing usage of Blast-Furnace Slag at cold-weather-concrete, it is investigated the strength properties of concrete subjected to frost damage for the cause of early age curing. The factors of this experience to give early frost damaged were Freezing temperature(-1, -10, $-15^{\circ}C$), Early curing age(0, 12, 24, 48hour), Freezing times(0, 12, 24, 48hour). According to this study, if early curing is carried out before haying frost damage, the strength of concrete used admixture, subjected to frost damage, is recovered. And that properties are considered, the effect of using admixture like blast-furnace-slag, is very high

• Food Engineering Progress
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• v.14 no.4
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• pp.328-334
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• 2010

Recently the enhancement and development of makgeolli processing to extend shelf life are constantly accomplished. However, the standardization to restrict microorganisms including cold chain system and sterilizing system has not been established yet. Therefore, the objective of this study was to investigate the storage stability of makgeolli using quick freezing (QF) and slow freezing (SF) storage methods. The storage period was 40 days. Every 10 days, the samples were taken from the quick and slow freezing storage chamber. And then the samples were put into a $10^{\circ}C$ refrigerator for 24 hr to thaw them. The final samples were evaluated for chemical experiments and microbial cell counts. As a result, reducing sugar content was dramatically increased after 10 days for all of the samples. In titratable acidity and color values case, these values did not significantly change by storage time. In case of lactic acid bacteria and yeasts for all the samples, there was a decreasing tendency with storage time. Especially, in case of lactic acid bacteria, the changes from the beginning microbial cell counts ($4.1{\times}10^7$ CFU/mL) for QF and SF after 20 days were $3.6{\times}10^6$ CFU/mL and $1.8{\times}10^4$ CFU/mL, respectively. This result showed that the freezing methods could restrict the microbial growth in makgeolli.

• Journal of Korea Water Resources Association
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• v.46 no.11
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• pp.1089-1101
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• 2013

The study uses a regional climate model to check future changes in extreme climate, to calculate extreme indexes presented by STARDEX, and to analyze the trends to predict the continuity and changes in the spatial distribution of extreme climate in the future. An analysis of extreme climate indices showed that they are likely to increase in the Seoul metropolitan area, in Gyeonggi-do, in Yongdong in Gangwon-do, and in the southern shore region of Korea. It is, however, forecasted to diminish in the central inland region. The analysis also showed that the average temperature in Korea will increase because of climate change. On the other hand, an analysis of extreme rainfall indexes showed that the trend of heavy rainfall threshold is 0.229 in Seogwipo, the greatest five-day rainfall is 5.692 in Seogwipo, and the longest dry period is 0.099 in Sokcho. Of extreme temperature indexes, the trend of Hotdays threshold is 0.777 in Incheon and the longest heat wave is 0.162 in Uljin. The Coldnight threshold is 0.075 in Inje and -0.193 in Tongyeong, according to the analysis.

• Journal of Oral Medicine and Pain
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• v.25 no.3
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• pp.265-276
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• 2000

스트레스가 타액선 조직을 변형시키고 파괴시킬 수 있다는 것은 이미 보고된 바 있다. 이는 구속스트레스 시에 관찰되는 apoptosis에 의한 것인데, 이 과정에 관여하는 caspase-3는 세포의 DNA를 분절시킴으로서 apoptosis를 일으킨다고 알려진 세포내 단백효소이다. 이에 기존에 관찰되었던 구속 스트레스에 의한 apoptosis의 형태적 변화가 apoptosis를 유도하는 caspase-3와 어떠한 시기적 상관관계를 가지고 있는지를 구명하기 위하여 본 실험을 시행하였다. 웅성 백서 (Sprague-Dawley, 8주) 를 사용하여 실험 전 기간에 걸쳐 구속스트레스를 가한 후 30분, 1시간, 3시간, 6시간, 24시간, 3일, 5일, 7일에 희생시켰다. 그 후 실험동물의 악하선을 절취하여 동결절편을 제작한 후, caspase-3에 대한 형광항체로 면역형광법을 시행하여 관찰하였다. 1. 정상대조군에서는 caspase-3가 타액선 조직 전반에서 미약하게 관찰되었다. 2. 구속스트레스 부여 30분에서 caspase-3는 강반응을 보였고, 실험기간이 경과됨에따라 점차 6시간군에서 부터는 현저히 감소하였다. 3. Caspase-3는 구속 스트레스 30분에 도관과 선포세포 모두에서 발현되었으나, 선포세포에서는 조기에 급격히 소실되었고 도관세포에서는 전 실험 기간에 걸쳐 서서히 소실되었다. 이와 같은 연구 결과에서, 세포내 caspase-3는 조직의 형태적 변화가 나타나기 이전에 발현하는 것으로 보아 caspase-3는 형태적 변화를 예견할 수 있는 진단 지표로 사용될 수 있을 것으로 사료되며 이후 임상적으로 적용하기 위한 지속적인 연구가 필요할 것으로 생각된다.

• Journal of Conservation Science
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• v.21
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• pp.49-58
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• 2007

Among the treatment results of test samples of the antique lacquer-ware, the treatment with PEG#3,350 40% solution displayed excellent effect with low shrinkage ratio; in weight gain the treatment with Sucrose 19%+Glycerin 1%(t-butanol 5% in water) solution showed consistent increase. However during the impregnation process of Sucrose, the weight of the testing samples decreased by dehydration because the inner part of the test samples and the treatment solution showed concentration gradient. Therefore, we concluded longer impregnation period should be necessary to prevent dehydration. Since both higher and lower molecular weight treatment chemicals could penetrate into the wood of the lacquer-ware, air drying and conditioning after impregnation treatment with high concentration chemicals would be possible, as well as vacuum freeze-drying.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.7 no.1
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• pp.7-12
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• 2014

Purpose:The effectiveness of transdermal buprenorphine patch on the patients with frozen state of frozen shoulder was evaluated. Materials and Methods: Between March and September in 2013, 127 patients with pain and limited range of motion in shoulder joint over 6 months were included. Every patient was confirmed the diagnosis through MRI or ultrasonogram and each patient received intra-articular injection of steroid once. After 2~4 weeks, every patient was interviewed via telephone survey and finally 105 patients were included, 54 patients received only oral NSAIDs (NP group) while 51 patients received additional transdermal buprenorphine patch (BP group). Pain and functional visual analog scale (PVAS, FVAS), American Shoulder Elbow Society (ASES) score was checked. Results: Generally, every outcome variables showed improvements in both groups (p<0.001). PVAS score after treatment showed superior result in NP group but it was not significant (p=0.088). In ASES score, NP group had superior result than BP group and it had significant difference. Similarly in FVAS, NP group showed superior result but the data before treatment was significantly different (p=0.028) Conclusion: Transdermal buprenorphine patch didn't show superior treatment result in the patient with frozen state of frozen shoulder which was applied with oral NSAIDs after single intra-articular glenohumeral steroid injection in short-term follow-up.

• Journal of Periodontal and Implant Science
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• v.28 no.4
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• pp.577-604
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• 1998

chitosan은 골치유증진 및 골세포의 분화를 촉진하는 것으로 알려진 천연의 생분해성 고분자이다. 이연구에서는 chitosan 및 chitosan/tricalcium phosphate(TCP) 다공성 기질을 제조하여 골이식재 및 조직공학적 골형성을 위한 3차원적 세포배양 지지체로서의 가능성을 평가하고자 하였다. chitosan 용액 및 TCP가 포함된 chitosan 용액을 동결건조함으로써 소공의 크기가 $100-200{\mu}m$인 스폰지형태의 chitosan 및 chitosan/TCP 다공성 기질을 제작하였다. 골이식재로서의 효과를 평가하기 위하여 백서의 두개골 결손부에 제작된 chiosan 및 chitosan/TCP 다공성 기질을 각각 이식하고 2주 및 4주 후에 동물을 희생하여 조직학적으로 치유양상을 관찰하였다. 조직공학적 골형성을 위한 세포배양 지지체로서의 가능성을 평가하기 위하여 백서 태자의 두개골에서 분리된 골아세포를 chitosan 및 chitosan/TCP 다공성 기질에 각각 접종하고 56일간 배양하면서 각 기간 별로 세포수, 염기성 인산효소 활성, 축적된 calcium의 양을 측정하였고 배양된 세포-기질 혼합체를 광학현미경 및 주사전자현 미경하에서 조직학적 관찰을 시행하였다. 백서 두개골결손부에 이식된 chitosan 및 chiosan/TCP 다공성 기질은 별다른 이물반응 없이 자연 분해되면서 신생골조직 내에 매립되었으며 이식하지 않은 대조군에 비해 유의하게 높은 신생골형성 효과를 나타내어 우수한 골전도성이 있음이 확인되었다. 신생골형성 양상이나 형성된 양에 있어서 두 가지 기질간의 유의한 차이는 없었다. 골아세포-기질 혼합체의 배양결과, 접종후 배양 28일 경과 시까지 골아세포수는 지속적으로 증가하다가 이후에는 5 8일까지 성장정도가 둔화되었다. 염기성 인산효소의 활성 및 calcium 축적량은 접종후 배양시간경과에 따라 56일까지 지속적으로 증가하였다. 세포수 및 염기성 인산효소의 활성에서 두 기질간의 유의한 차이는 없었고, calcium 축적량에 있어서는 chitosan/TCP 기질에서 유의하게 높았고 증가속도도 컸다. 배양된 골아세포가 접종된 다공성 기질의 조직학적 관찰결과, 골아세포는 다공성 기질에 잘 부착하여 중층의 형태로 성장하면서 광화된 골기질을 형성함이 관찰되었다. 배양 14일부터 작은 골편형태의 골형성이 기질 표면에 부착되어 관찰되었고, 배양기간이 길어짐에 따라 성장하여 배양 56일째에는 상당한 양의 광화된 골질이 형성됨이 관찰되었다. 배양 56일 경과후의 광화된 골질의 양은 chitosan/TCP 기질에서 더 많았다. 이 연구의 결과, chitosan 및 chitosan/TCP 다공성 기질이 골이식재로서 뿐만 아니라, 조직공학적 골형성에 적용되는 골아세포의 배양을 위한 3차원구조의 세포지지체로 이용되어 골재생술식에 유용한 생체재료로 활용될 수 있음이 확인되었다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.3
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• pp.221-228
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• 2001

This study was carried out to investigate the effect of germination condition and drying temperature on growth and physicochemical properties of brown rice. Three brown rice seeds of Ilpumbyeo, Dasanbyeo and Heugjinjubyeo were stored at room temperature for six weeks to test the time-sequence germination viability. Relatively stable germination ratio was maintained until 2 weeks after storage. However, 3 weeks after storage, germination ratio of brown rice seeds started to decrease rapidly and their germination ratio was lower than 80%. For this reason, brown rice was recommended for seeding within 2 weeks after hulling. During the initial 5 days, germination ratio of 24 hours pre-soaking brown rice was higher about 2-3% than that of non-soaking brown rice. The $25^{\circ}C$ was considered as the most favorable temperature for brown rice germination, because of the high germination ratio and desirable coleoptile growth of the brown rice, and little seed rotting symptoms. The scanning electron micrographs showed the structural differences between hot-air dried and freeze dried germinated-brown rice kernel. In the freeze dried germinated-brown rice, seed coat (pericarp, tegmen and aleurone layer) was mechanically disrupted from the endosperm, and many cleavages were observed among starch storing cells and starch granules. The endosperm of freeze-dried brown rice kernels formed the sponge-like structures and showed the fragile traits. For this reason, hot-air drying is considered as more suitable method than freeze drying for germinated-brown rice. The crude protein and amylose contents were slightly changed, but there were no significant differences during the germination period. Crude fiber content was decreased, but crude Int and total amino acid contents were increased as seeding days increased. A rapid increase in $\alpha$-amylase activities of germinating brown rice was observed at S days after seeding, and $\alpha$-amylase activities were decreased from 8 days after seeding. Total free sugar contents were decreased during the germination period. There was continuous decline in the contents of sucrose and glucose until 8 days after seeding, but fructose and maltose content were gradually increased from the 5 days after seeding.