• Title/Summary/Keyword: freezing in summer

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A Geomorphological Study on the Distribution Areas of Freezing during Summer Season in Korea (한국의 하계 동결현상 분포지에 관한 지형학적 연구)

  • Jeon, Young-Gweon
    • Journal of the Korean association of regional geographers
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    • v.7 no.1
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    • pp.97-106
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    • 2001
  • There are a few interesting areas which show freezing during summer season in Korea, three of them are especially important. They are located at Milyang(Gyungnam province), Uisung and Chungsong(Gyungbook province). They are named Eoleumgol(ice-valley) or Binghyul(ice-cave). The purpose of this study is to clarify geomorphological and geological characteristics about the distribution areas of freezing during summer season in Korea in relation to previous works, which have been studied in hydrological or micro-climatological viewpoints. The main results are summarized as follows. 1) The main geomorphological and geological characteristics in the distribution areas of freezing during summer season (1) Thick debris accumulated slope within deep valley (2) North facing slope (3) The component debris of volcanic rock such as andesite or rhyolite 2) The ice-cave as a system that give rise to freezing phenomenon in summer season is closely related to talus slope. The ice-cave has thick accumulated debris and lots of vacant spaces within the rock deposits, some of vacant spaces are very big and connected with underground water system. 3) A partly freezing within underground water system is required freezing phenomenon in summer season. Judging from this point of view, two ideas are suggested; one is the evaporation theory, another is that the frozen condition in winter remains untill late summer.

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A Study on Cooling and Freezing During Summer Season in Deoksan-ri Eoreumgol (ice valley) Yeongdeok-gun (South Korea) (영덕군 덕산리 얼음골의 냉각 및 하계 결빙현상에 관한 연구)

  • Lee, Jin Kook;Shin, Jae Ryul;Jang, Yun Deuk
    • Journal of the Korean association of regional geographers
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    • v.21 no.3
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    • pp.608-617
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    • 2015
  • This paper synthetically analyzes micrometeorological data and geomorphological features of Doeksan-ri Eoreumgol(ice valley) Yeongdeok-gun in order to investigate occurrence characteristics of the ice valley and a mechanism for freezing in summer. This ice valley is located in the distal end of a talus and intensity of cooling and freezing in summer seems to be related to morphology and dimensions of talus. Cooling in the ice valley is generated by cold air flows that move down to the bottom of talus from high mountains through pores and voids, then debris in talus is supercooled by the cold air. For it forms a stable state in and around voids cold air is stagnating in the lower end of talus. This causes freezing in summer at outpour points. Furthermore humidity condition of external air and vaporization heat is a key factor when freezing.

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THE CHANCES OF PERMAFROST INDUCED BY GREENHOUSE WARMING: A SIMULATION STUDY APPLYING MULTIPLE-LAYER GROUND MODEL

  • Yamaguchi, Kazuki;Noda, Akira;Kitoh, Akio
    • Proceedings of the Korea Society for Simulation Conference
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    • 2001.10a
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    • pp.329-334
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    • 2001
  • Many of past studies using physically based numerical climate models indicate that increases in atmospheric $CO_2$could enhance summer dryness over continental region in middle-high latitudes. However the models used in those studies do not take account of permafrost in high latitudes. We have carried out a set of experiments applying a version of global climate model that can reproduce realistic distribution of the permafrost. From the results, it is indicated that permafrost functions as a large reservoir in hydrologic cycle maintaining dry, hot summer over continents in northern middle-high latitudes, and that the $CO_2$warming would reduce this function by causing climatological thawing of permafrost, which would result in moister and cooler summer, and warmer winter in the same region. The present study indicates that an inclusion of very simple description of soil freezing process can make a large difference in a model simulation.

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The design concept of the cubicle to improve freezing performance for high speed train (고속열차 배전반의 냉각성능 신뢰성 향상 방법에 대한 연구)

  • Choi, Kwon-Hee;Jeong, Byung-Ho;Lee, Byung-Seok;Park, Jong-Hun;Lee, Jong-Woo
    • Proceedings of the KSR Conference
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    • 2007.05a
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    • pp.905-910
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    • 2007
  • The cubicle of high speed train is the equipment where the important train- operating equipments are concentrated, so it requires the higher safety and reliability than any other equipment. Recently, the power car cubicle of KTX-II is, basically similar to that of KTX-I and HSR350x in its size, but consequently, as more sophisticated ATP/ATC and other parts are added, the order company points out the problem of rising temperature in summer. Especially, the interpretation about the possibility of guaranteeing the minimum freezing performance becomes necessary, when Fan Tray is out of order. This paper presents the method of improving the freezing performance while minimizing the effect of dust, and the method of guaranteeing the present freezing performance by the best arrangement of Fan Tray, when Fan Tray is out of order. And as a method of verifying this, we would like to predict the pressure, speed of a running fluid and temperature distribution of cubicle through the flow analysis.

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Study on the freshness change of Pacific Macheral, Hair Tail, and Alaska Pollack by the various storage conditions (고등어, 칼치, 명태의 선도변화에 관한 연구)

  • 김영희
    • Journal of the Korean Home Economics Association
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    • v.19 no.1
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    • pp.39-45
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    • 1981
  • The fishes that are mostly used in our homes such as Pacific Mackeral, hair Tail and Alaska Pollack were devided into Freezing group, Refrigerating group and Room temperature group according to storage temperature. TVB-N, TMA-N, TMA-O and pp.H. were measured in natural state, after water washing and 3% NaCl-water washing. The results are as follows: 1. Regardless of the kinds of fishes, TVB-N in room temperature showed that rottenness first appeared after 5~8 hours in raw state, 6~12 hours in water washing, and 8~12 hours in 3% NaCl-water washing. 2. Regardless of freezing and refrigeration, Pacific Mackeral became rotten after 14 days in raw state, 14~17 days in water washing and 17 days in 3% NaCl water washing. Alaska Pollack and Hair Tail showed rottenness after 8 days in raw state, 11 days in water and 3% NaCl water washing. 3. Even in hot summer days, freshness could be preserved for 10 days if fishes were freezed ($-20^{\circ}C$) or refrigerated (4~$8^{\circ}C$) after bowel excluded, washed in NaCl water and enveloped in poly-ethylene bag.

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Effect of Season on Testis Function and Freezing and Fertilizing Ability of Spermatozoa in Korean Native Goat I. Seasonal Changes in Semen Characteristics and Freezing and Penetrating Ability of Sperm (한국재래산양에서 계절이 정소기능, 정자의 내동성 및 수정능력에 미치는 영향 I. 정액성상과 정자의 내동성 및 난자침입능력의 계절적 변화)

  • Kim, C.K.;Chung, Y.C.;Kim, K.S.;Yoon, J.T.;Lee, J.H.;Chung, Y.H.;Choi, S.H.;Kim, H.Y.;Kim, S.;Kwon, C.J.
    • Korean Journal of Animal Reproduction
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    • v.17 no.4
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    • pp.311-323
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    • 1994
  • This study was conducted to observe seasonal and individual changes in semen characteristics and sperm freezability, and sperm penetration into zona-free hamster eggs in Korean native goats. Buck response and change in semen characteristics to electrical stimulations was evaluated for four seasons throughout 2 years and percentage of motile sperm and normal apical ridge acrosome was investigated after equilibration and thawing for 4 seasons with 5 bucks. Sperm penetration rate was evaluated for 4 bucks. 1. Probe insertion at depth of 7cm and repeated stimulation for 3 sec was more effective(P<0.05) in buck response and semen collection than those of other conditions. 2. Semen characteristics from electrojaculation was signficantly(P<0.005) higher in spring and fall for semen volume, in spring and summer for sperm concentration and in fall for sperm motility than those in other seasons, respectively. However, there were no differences in total sperm among seasons. 3. Buck response to electrical stimulation showed significant difference(P<0.05) among individuals in all 3 seasons except winter. Significant individual difference in semen volume was only in spring and summer, but there was no indivudual difference in sperm concentration and total sperm in all season. 4. Washing of semen before freezing treatment was greatly(P<0.05) beneficial to sperm motility after thawing, no matter whether ejaculates exhibit egg yolk coagulation or not. 5. Sperm motility after glycerol equilibration was significantly(P<0.05) low in summer semen and motility after thawing was greatly(P<0.05) higher in winter semen than in other seasons. Freezability of unwashed sperm was significantly difference among bucks, but a yearly freezability of washed sperm after chilling and thawing were no differences among bucks and percentage of normal apical ridge acrosome were not different among seasons and bucks. 6. There was no significant difference in sperm motility after thawing between egg yolk levels in summer, although 20% level gave more higher motility than 5% level. 7. In summer, 3.2% glycerol and 3-h equilibration gave greatest percentage(P<0.05) of sperm motility and normal apical ridge acrosome after thawing. 8. Sperm penetration rate into zona-free hamster eggs was not different between bucks and seasons. Overall, it is concluded that to obtain maximum sperm output and successive semen freezing by electrojaculation method, buck selection with good response in all season could be basically considered and that seasonal effect on sperm freezability was more greater than that of individual bucks.

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Temporal Variation of Air Temperature in Ice-Valley at Milyang in Association with Ice Formation

  • Lee, Soon-Hwan;Hwang, Soo-Jin
    • Journal of the Korean earth science society
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    • v.28 no.5
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    • pp.598-602
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    • 2007
  • A long-term in situ observation was carried out in the Ice-valley at Milyang in order to explain the factors and processes associated with the summertime ice formation. The variation of temperature inside Ice-valley in relation with ice formation in summer time was found to depend on precipitation rate in spring and cold air sinking in autumn and winter. The rate of temperature rising tends to correspond to sensible heat release depending on the precipitation amount at the freezing location. The reason of the cold air accumulation in a talus in the Ice-valley is the cold air sinking over the surface of talus due to the occurrence of outside clod air mass and the accumulated cold air from autumn to spring flow outside at the bottom of talus. The out-flowing cold air can result in the ice formation in the hot summer.

Hydrological Study of the Freezing in Summer Season at the Ice Valley, Korea (얼음골의 하계 결빙현상에 관한 수문학적 연구)

  • 배상근
    • Water for future
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    • v.23 no.4
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    • pp.459-466
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    • 1990
  • In the Ice Valley, it freeze in summer season. However, there is no ice during winter. In order to clarify the phenomenon of unusual temperature, numerical experiments were conducted using the coupled equations of fluid flow and heat transfer. The results demonstrated that temperature inversion in the Ice Valley is primarily due to delay of the groundwater temperature. Also, the results of the simulation suggest that major factors affecting the delay are the topographical configuration, geological factors and groundwater flow system, combined with groundwater recharge and discharge systems.

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Studies on the Properties of Simmental Semen I. With Special Reference to Collecting Semen During Summer (Simmental의 정액성상에 관한 연구 제1보, 정액의 하계수취를 중심으로)

  • 고광두;한두희;정길생
    • Korean Journal of Animal Reproduction
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    • v.5 no.2
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    • pp.43-48
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    • 1981
  • This experiment was carried out with the purpose to get some information about the properties of Simmental bull semen during summer season. The results obtained were summarized as follows: 1. Semen volume per ejaculation, sperm concentration and sperm viability were averaged 5.16ml, 6.6billion and 65%, respectively. 2. Percentage of motile sperm after dilution in skmmilk solution and trisbuffer for 5 days were 34.16% and 35.0%, respectively. 3. Viability of spermatozoa frozen in skimmilk extender and trisbuffer for 5 days were 20. 83% and 25.66%, respectively. 4. Percentage of live sperm, MRT and pH value were 71.8∼72.1%, 8.40∼8.21 minutes and 6.78, respectively. 5. Diluted semen showed strong resistance to the cold shock than that of fresh semen. 6. Rscovery of sperm motility after freezing for 24 hours was relatively weak.

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An Experimental Study on the Effectiveness of Soil Compaction at Below-Freezing Temperatures (동결 온도에서 다짐효과에 관한 실험적 연구)

  • Hwang, BumSik;Chae, Deokho;Kim, Youngseok;Cho, Wanjei
    • Journal of the Korean GEO-environmental Society
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    • v.16 no.1
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    • pp.37-43
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    • 2015
  • Korea has four distinct seasons, showing hot and humidity in summer and cold weather lasted in winter. Domestic research on earth work has been developed according to the seasonal characteristics, and most of research topics have focused on the effect of freezing-thawing on the performance of geo-materials. However, the previous research was performed on the ground compacted at room temperature and therefore, the effect of the sub-zero temperature at the time of construction was not fully investigated. The ground characteristics compacted at freezing temperature can be different from those at room temperature and show different characteristics of strength and deformation caused by freezing and thawing. Therefore, the compaction tests on sandy materials were conducted under various temperature at $-3^{\circ}C$ and $-8^{\circ}C$ with various fine contents of 0%, 5%, 10% and 15% in weight fraction. The effectiveness of soil compaction at below-freezing temperatures were compared with the compaction at room temperature at $18^{\circ}C$ in terms of the maximum dry unit weight and optimum water contents. Based on the test results, the maximum dry unit weight tends to decrease with the freezing temperature and the relative compaction at $-8^{\circ}C$ can not be satisfied with general specification standard.