• 한국도로학회:학술대회논문집
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• 2010.03a
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• pp.131-138
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• 2010

• Journal of Korean Society of Transportation
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• v.15 no.3
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• pp.7-23
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• 1997

우리나라의 전면적인 약 95%가 계절적 동결지역에 속하며 동상과 융해로 인해 도로등 지반구조물은 피해을 입는다. 본 논문에서는 국립건설시험소의 10년간 실측자료중 지역별로 대표하여 15개 도시 528개 지점을 선정하여 최대동결지수를 4개 그룹(250이하, 250∼400, 400∼600, 600이상)으로 분류하여 분석하였다. 또한 동결심도 계산에 동결지수외에 흙의 함수비와 전조밀도를 각각 추가로 고려하여 새로운 산정식을 제시하였다. 그리고 지역에 따른 과다산정을 막기 위하여 동결지수 분류별로 4그룹으로 세분화하여 경제적인 설계가 가능하도록 하였다. 새 제안식과 기존식을 비교하여 보았을 때 새 제안식이 기존식보다 전반적으로 크게 산정되나 그 지역의 함수비나 건조밀도를 추가로 고려하였으므로 보다 합리적인 산정식이라 할 수 있다.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.179.2-180
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• 2003

본 연구에서는 과채류의 냉동냉장시 내부압력에 따른 조직파괴를 방지하기 위한 기초연구로 동결방법에 따른 내부압력 변화에 대하여 조사하였다. 과채류의 동결에 의한 중량감소율은 침지식 동결방식에서 0.44∼l.38% 수준으로 가장 적게 나타났으며, 동결방식에 따른 중량감소율 차이는 수박에서 가장 심하여 수분함량에 클수록 동결속도에 따른 효과가 비교적 크다는 것을 알 수 있었다. 동결속도에 따른 내부압력은 배, 사과 및 메론에 있어 침지식 방법에 의한 동결시 체적팽창 및 수축에 따른 내부압력 차가 가장 적게 나타났으며, 송풍식 동결에서 가장 크게 나타나 동결속도가 빠를수록 내압의 크기는 적다는 것을 알 수 있었으나 딸기 및 수박의 경우는 오히려 침지식에서 내압이 가장 크게 나타났다. 균온 처리하지 않은 동결에 있어 과일의 내부압력 변화는 약 2 psig수준인 반면에 균온 처리한 수박의 내부압력 변화는 균온 처리하지 않은 수박의 내부압력 변화 경향과 유사하지만 일정한 수준의 내압을 발생시킴으로써 내부압력의 크기도 약 1.3 psig수준으로 상당히 적게 나타났다. 또한, 해동시에 있어서도 균온처리한 시료의 내부압력 크기가 균온처리하지 않은 내부압력 크기보다 상대적으로 적게 나타났다. 균온처리 동결시, 다단계 처리보다는 3∼4회 수준의 일정한 균온 처리가 내부압력의 증감 폭을 줄일 수 있었다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.5-6
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• 2015

Recently, freezing index of frost penetration depth estimation used in Korea is applied according to the standard, published by MOLIT in 2003. However, it is difficult to consider can not be determined to standard reflects weather conditions in accordance with the current climate warming or abnormally high temperature. Also the temperature should be considered local variables because heavy local gap. Therefore, this study is through the freezing index presented in MOLIT's code by calculating the frost penetration depth determining whether the adequacy and conducted a study to apply in the field. As a result, when the Elevation 100m to standard in Incheon frost penetration depth is found to be 50.8cm.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.78-89
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• 2008

In this study the frost penetration depth along national roads in Korea were measured and analyzed over several years. The frost penetration depth was analyzed with respect to the Provinces of Korea and sunny/shaded areas. Additionally, the measurement results were compared to the formular of the US Army Corps of Engineers and Terada in Japan.

• The Journal of Engineering Geology
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• v.17 no.3
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• pp.359-365
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• 2007

Freezing and thawing cycle is one of the major weathering-induced factors in the mechanical weathering of the rock mass. This natural process accelerates rock weathering process by breaking down the parent rock materials and makes soil or weathered rock formation in a rock slope surface zone. It can also cause reduction of the shear strength in slopes. It is important to calculate the deterioration depth caused by freezing-thawing for a slope stability analysis. In this study, deterioration depths of rock slope due to freezing-thawing were calculated using the 1-D heat conductivity equation. The temperature distribution analysis was also carried out using collected temperature distribution data for last five years of several major cities in Korea. The analysis was performed based on the distributed rock types in study areas. Thermal conductivities, specific heats and densities of the calculation rocks are tested in the laboratory. They are thermal properties of rocks as input parameters for calculating deterioration depths. Finally, the paper is showing the calculated deterioration depths of each rock type slopes in several major cities of Korea.

• Geotechnical Engineering
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• v.5 no.4
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• pp.5-16
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• 1989

This paper statistically analyses the freezing soil by frost group and frost depth in Korea with data from soil testing in the Korea National Housing Corporation, the climate data provided by the Central Weather Office and the data on the frost depth from the National Construction Laboratory Institute. In this paper, freezing variable are analysed such as percentage finer than 0.02 m by weight, plasticity index, freezing index, water contents of soil and frost depth etc‥‥ The result of the analysis is as follows. 1) The frost depth of Korea depends on the properties of soil rather thank the characte fistic of area. 2) The distribution map of design freezing index in 57 cities is drawn up with the maxi- mum freezing index, during past 14 years, calculated by the average of the air temperature observed four times(03 : 00.09 00, 15 : 00, 21 : 00) a day. 3) By correcting the OLS line estimated from the relationship between freezing index and frost depth, a method of utlizing the line with the upper confidence limit of 99.9% int-distribution as predicted maximum frost depth is newly introduced.

• Communications for Statistical Applications and Methods
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• v.5 no.1
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• pp.217-223
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• 1998

공통의 자유도를 갖는 $textsc{k}$개의 비중심 카이제곱분포들의 동질성을 검정하기 위하여 우선 적당한 형태의 검정방법을 제시하였다. 통상적인 방법대로, 제시된 검정방법이 주어진 유의수준을 만족시키도록 하기 위해서는, 귀무가설하에서 제 1종의 오류의 확률을 최대화하는 모수의 최소 우호적 위치(Least favorable configuration)가 유도되었으며, 이에 따라서 주어진 유의수준을 충족하는 기각치를 도표화하였다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.10 no.2
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• pp.79-90
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• 1990

The National Construction Research Institute of Korea has measured the depth of the frozen ground covering all the areas of South Korea during ten years ranging through 1980. The measurements were made for the frozen ground at random but intended for the most frost-susceptible soils. The soils of the frozen ground were sampled and then classifide into four groups according to the frost design soil classification system suggested by the Corps of Engineers of the United States. The contours of the maximum depth of the frost penetration are drawn on a map with data collected during the ten years. Also isolines of the design frezing index are shown on an another map using the metorological information of 1980-1989 and compared whth those in vestigated in 1980 by Highway Survey Team of the Ministry of Construction, Korea. It is known that the maximum depth of the frost penetration is related to freezing index values. An empirical formula expressing the relation is suggsted, in which the depth is proportional to the one-third power of the air freezing index values.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.3
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• pp.131-136
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• 1979

Histological changes of yellow sea bream, Branchiostegus japonicus japonicus, were observed under microscope during freezing storage for 6 months at $65^{\circ}C$ and $-35^{\circ}C$, and the results were compared with the muscle structure of fresh muscle. The freezing storage of yellow sea bream at $-^{\circ}C$ showed more changes in muscle structure than that stored at $-35^{\circ}C$. In the view point of the changes of the muscle structure, the yellow sea bream can be stored up to 1 month at $65^{\circ}C$ and 3 months at $-35^{\circ}C$. The freezing of yellow sea bream at $-5^{\circ}C$ showed higher extracellular freezing than that at $-35^{\circ}C$.