• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.846-853
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• 2005

The whole death by disaster is totalized to 1,515 person from 1993 to 2004 year in our country. In this section life damages by landslide is totalized 357 people(about 24% of whole life damage). About 36 people are died by landslide(such as cutting area failure every year). Kangwon-do need a lot of interests and prevention because dangerous area that landslide occurrence is more than other area at summer localized downpour or thawing season and there is landslide occurrence possibility area more than other area. Kangwon-do area is higher than other area in natural disaster incidence and damage scale because topography and a lot of rainfalls by summer localized in Kangwon-Do than other area. In this study, dangerous area of landslide occurrence possibility is analyzed and compared Kangwon-Do with other areas in our country. as a result, every year we have experienced landslide occurrence and natural disaster. accordingly, we urgently need to prevent landslide occurrence and natural disaster by analy-zed source about landslide occurrence and condition of disaster in Kangwon-Do and suitable engineering method and construction work.

• International Journal of Highway Engineering
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• v.19 no.3
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• pp.1-10
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• 2017

PURPOSES : This paper focuses on strength development according to the mix design with cement type and mineral admixture from laboratory and field tests in cool weather. METHODS : Two methods evaluated the mix design of concrete pavement in cool weather. Firstly, laboratory tests including slump, air contents, setting time, strength, maturity, and freezing-thawing test were conducted. Three alternatives were selected based on the tests. Secondly, a field test was conducted and the optimum mix design in cool weather was suggested. RESULTS : It is an evident from the laboratory test that a mix with type III cement showed better performance than the one with type I cement. There was a delay in strength development of a mix with mineral admixture compared to mix design without any mineral admixture. In the field test, type III cement+flyash 20% mix design proved the best performance. CONCLUSIONS : For concrete pavement in cool weather, mix design using type III cement could overcome the strength delay due to mineral admixture. Moreover, it is possible to make sure of durability of pavement. Therefore, strength and durability problems due to cool weather would decrease.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.6
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• pp.849-855
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• 1996

Processing condition and pigment maintenance of cockle, Fulvia mutica were studied. Proximate composition of whole meat was $82.3\%$ moisture, $10.8\%$ crude protein, $0.8\%$ crude lipid, $2.5\%$ carbohydrate and $3.1\%$ crude ash, and that of foot muscle was $80.6\%,\;12.3\%,\;0.3\%,\;2.9\%\;and\;3.3\%$ respectively. When the living cockle was soaked in $2\%$ NaCl solutions, about $90\%$ of silt and mud was removed after 10 hours soaking, and over $92\%$ was removed when the pH was adjusted to 7.5. When the pigment destruction was tested by 40 seconds at $75^{\circ}C,\;80^{\circ}C,\;85^{\circ}C,\;90^{\circ}C\;and\;95^{\circ}C$, retention ratios of pigment in cockle were above $95\%$ at all temperature. Soaking in ethanol for 5 minutes resulted in strong adhesion of pigment to meat. Soaking in seasoning liquid containing $10\%$ soy sauce, $5\%$ wasabi, $5\%$ sugar, $2\%$ vinegar, $2\%$ powdered garlic for 3 minutes was effective for instant processing of cooked and frozen cockle after thawing. After 60 days storage at $-20^{\circ}C$, the contents of moisture, crude lipid, carbohydrate, ash and salinity were not changed so much, and pH and TBA values increased to 6.6 and 0.3 compared with 6.2 and 0.2, respectively, while pigment absorbance at 226 nm was decreased from 2.7 to 2.3. However, in case of 60 days storage at $-45^{\circ}C$, there was no change in these compositions.

• Journal of the Korean Geotechnical Society
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• v.30 no.8
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• pp.39-47
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• 2014

Frost heaving and thawing settlement cause unexpected stress around buried pipelines, which results in deformation and permanent demage. A large scale laboratory test has been performed to observe deformation, stress, and temperature of a buried pipe during atmospheric temperature changes. From the experimental results, the stress concentrated around the buried pipe is inevitable and deformation is caused by the frost heaving. Even though backfill materials are sandy soils which are normally assumed to be non frost susceptible, it is revealed that frost demage can happen due to drainage condition, the level of ground water table, and water content.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.827-831
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• 1998

Effects of pre-pressing condition on quality of pear juice were investigated. Three different types of pressed pear juices such as heated-and-pressed pear juice (HPP), blanched-and-pressed pear juice (BPP), and thawed-and-pressed pear juice (TPP) were prepared. The yield and content of soluble solids in HPP were 78% and $15.0^{\circ}Bx$ which were higher than the other treatments, respectively. Acidity and pH of all the samples were about 0.2% and 4.9, respectively. Major free sugars and organic acids in HPP, BPP, and TPP were fructose and malic acid, respectively. Major soluble minerals were K, P and Mg, and miner ones were Na and Fe. HPP showed a lowest L value, but had a highest taste.

• Journal of the Korean Geotechnical Society
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• v.25 no.8
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• pp.95-106
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• 2009

This study was intended to identify the effect of the wetting on a long-term compression settlement of the rock/soil mixture used as fill material, depending on compaction and grading conditions. The relatively large settlement happened under the fully-submerged condition, and a repeated settlement was monitored when moisture content increased over and over again like the rainfall infiltration. In case of the materials without fine fractions or compacted in wet condition, the settlement caused by wetting was relatively low. In conclusion, the long-term compression settlement of granular (rock/soil mixture) fill material is more affected by the increase of water content and temperature change (freezing and thawing) than creep.

• Journal of the Korean GEO-environmental Society
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• v.14 no.7
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• pp.19-29
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• 2013

Analysis via classical soil mechanics theory is either ineffective or inappropriate for fully describing stress distribution or failure conditions in cold regions, since mechanical properties of soils in cold regions are different from those reported in the classical soil mechanics theory. Therefore, collecting and analyzing technical data, and systematic and specialized research for cold regions are required for design and construction of the structure in cold regions. Freezing and thawing repeat in active layer of permafrost region, and a loading condition affecting the structure changes. Therefore, the reliable analysis of mechanical properties of frozen soils according to various conditions is prerequisite for design and construction of the structure in cold regions, since mechanical properties of frozen soils are sensitive to temperature condition, water content, grain size, relative density, and loading rate. In this research, the direct shear apparatus which operates at 30 degrees below zero and large-scaled low temperature chamber are used for evaluating shear strength characteristics of frozen soils. Weathered granite soil is used to analyzed the shear strength characteristics with varying freezing temperature condition, vertical confining pressure, relative density, and water content. This research shows that the shear strength of weathered granite soil is sensitively affected by various conditions such as freezing temperature conditions, normal stresses, relative densities, and water contents.

• Korean Journal of Animal Reproduction
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• v.23 no.2
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• pp.141-148
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• 1999

This study was to test whether the viability of bovine hatched blastocysts (HBs) can be maintained after vitrification and thawing. The HBs were produced in vitro at Day 9 and Day 10 after IVF, and they were classified to small (S-HBs; ø$\leq$300 ${\mu}{\textrm}{m}$) and large(L-HBs; ø＞300 ${\mu}{\textrm}{m}$) on the basis of embryo diameter using eyepiece micrometer. As freezing solution, we used EFS35 which consisted of 35% ethylene glycol (EG), 18% ficoll, 0.3 M sucrose and 10% FBS added in mDPBS. Vitrification was taken by two-step method, the HBs were equilibrated in 10% EG for 5 minutes and then shortly exposed in EFS35 and plunged into L$N_2$for 30~45 sec. After thawing, the survival rates were assessed by the re-expansion of the blastocoel during 2 h and 16 h of culture. The results obtained in these experiments were summarized as follows; 1) When the blastocysts(40.8%) recovered at Day 8 after IVF were further cultured for 24 h(Day 9 after IVF) and 48 h(Day 10 after IVF), the rates of HBs were 20.5% and 6.7%, respectively. Also, the total cell number of HBs on Day 9 was significantly higher than that of HBs on Day 10 (p＜0.01). 2) When the effects of freezing solution to the survival of Day 9 L-HBs were examined, the rate of vitrified group (75.7%) was significantly lower than 100% of control and exposed group(p＜0.05). 3) When the survival rates of vitrified HBs according to size and developmental age were examined, the data of L-HBs (75.5%) and S-HBs(63.6%) on Day 9 were slightly higher than those of L-HBs(64.3%) and S-HBs(60.7%) on Day 10. 4) Also, when the in vitro survival of Day 9 HBs was evaluated under different culture condition after thawing, the result in culture medium only (79.3%) was significantly higher than 43.2% in co-culture group (p＜0.05). These results demonstrated that bovine HBs can be successfully cryopreserved by two-step vitrification method using EFS35.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.128-128
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• 2003

The aims of this study are 1) to test oocytes and embryos collected from in-vivo and in-vitro to achieving the valuable protocol by culturing, vitrifying and thawing of oocytes/embryos, and 2) to transfer them to recipient, and finally have resulted in pregnancies from recipient females after surgical or nonsurgical transfer. In vitro maturation and fertilization were performed according to the procedures of Funahashi et al. Fertilized oocytes were cultured in glucose-free NCSU 23 supplemented with 5 mM sodium pyruvate, 0.5 mM sodium lactate and 4 mg/ml bovine serum albumin for 2 days at 39$^{\circ}C$, and 10% fetal bovine serum was added to the culture medium thereafter. Embryos were treated with 7.5$\square$g/ml cytochalasin-B for 30 min, centrifuged at 13,000 ${\times}$ g for 13 min and then exposed sequentially to an ethylene glycol (EG) vitrification solution, aspirated into OPSs, and plunged/thawed into/from liquid nitrogen. In vivo embryos were surgically collected from three donors after Al. Forty-six embryos (18, 9 and 19 embryos, respectively) were washed 3 times in mPBS+10%FBS, followed treatments : cultured, centrifuged, vitrified, recovered and transferred to recipients as in vitro prepared embryos. Three recipients received surgically 34(control), 188 and 184 embryos (derived from abattoir), respectively. Another three recipients were received nonsurgically 150, 100 and 150 embryos, respectively. All recipient sows exhibited delayed returns to estrus. To our knowledge, these results suggest that required an improved techniques, more vigorous embryos preparation and cleaner uterous condition(use gilt).

• Journal of Embryo Transfer
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• v.26 no.3
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• pp.201-207
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• 2011

The present study was performed to investigate the survival and subsequent embryonic developmental rate of immature and mature oocytes after vitrification and pronuclear stage embryos after slow-freezing and vitrification. We have also tried to examine the dependency of concentrations (7.5, 15%) and exposure time (5, 10, 20 min) of ED cryoprotectant on developmental rate of pronuclear stage embryos. The developmental rates of 2-ce1l and blastocyst embryos at mature oocytes were significantly (p<0.05) higher than immature oocytes. After slow freezing, vitrification and thawing of pronuclear stage embryo, the survival and developmental rates of blastocysts and hatched blastocysts were significantly (p<0.05) higher after vitrification than after slow-freezing. On contrary, the developmental rates of 2-cell embryos were significantly (p<0.05) higher after slow freezing than after vitrification. The cryopreservation methods of pronuclear stage embryos vitrified by exposed to 7.5% ED solution for 5 minutes was significantly (p<0.05) higher than other experimental group. The results of our study suggest 1hat the developmental rates of mature oocytes have been more successful than immature oocytes during vitrification. Vitrification was more efficient than slow freezing in case of pronuclear stage embryos. The effective cryopreservation method of pronuclear stage embryos was vitrified by exposed to 7.5% ED solution for 5 minutes.