• 제목/요약/키워드: cold region

검색결과 700건 처리시간 0.028초

한중 콘크리트의 적용기간 설정에 관한 기초적 연구 (A Fundamental Study on the Application of the Period in Cold Weather Concrete)

  • 한민철;백승대;윤기원;한천구;김무한
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1996년도 봄 학술발표회 논문집
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    • pp.408-413
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    • 1996
  • The purpose of this study is to present the reference data about the period in cold weather concrete practice based on meteorological data of Korea meteorological administration in our country in comparison with previous study and specifications of foreign country as to cold weather concrete such as ACI, JASS-5 and JSCE. The results of this study indicate that the period of cold weather concrete by each specifications in most of the region except Cheju island and coastal region in Korea is lasted over 100 days and the period of cold weather concrete in hillsides and inland areas is longer than that of coastal regions in the same latitude.

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냉장고 내부의 냉기 유동특성에 관한 3차원 해석(I) (3-Dimensional Calculation on Cold Air Flow Characteristics in a Refrigerator)

  • 오민정;이재헌;오명도
    • 설비공학논문집
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    • 제7권3호
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    • pp.382-395
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    • 1995
  • A numerical study has been performed on flow characteristics in a domestic refrigerator whose size is $540mm{\times}1,530mm{\times}680mm$, considering existence of a fan and evaporator. The flow field has been simulated with the low Reynolds number $k-\bar{\varepsilon}$ turbulent model and SIMPLE algorithm based on the finite volume method. The region of fan which makes driving force for cold air distribution was modeled as a region in which momentum sources are generated uniformly. The concept of the distributed pressure resistance was applied to describe the momentum loss from evaporator. The result showed that the rate of cold air distribution into freezing room and cold storage room was almost 7 : 3.

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위성 및 현장 자료를 이용한 동해남동부 연안해역의 하계 냉수대의 단기변동 (Short-Term Variability of a Summer Cold Water Mass in the Southeast Coast of Korea Using Satellite and Shipboard Data)

  • 김상우;고우진;장이현;임진욱;야마다게이꼬
    • 해양환경안전학회:학술대회논문집
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    • 해양환경안전학회 2008년도 춘계학술발표회
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    • pp.169-171
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    • 2008
  • 본 연구에서는 위성관측 해양표면수온과 클로로필 영상 및 현장관측 자료를 이용하여 동해남부 냉수대 발생 주변해역의 단기변동을 조사하였다. 특히 본 연구에서는 2007년 8월 하계 계절풍 기간 동안의 동한난류 주변의 해양표면수온과 클로로필의 공간변동에 주목하였다. 본 연구기간에 조사한 동한난류 해역의 해양표면수온과 클로로필의 공간분포는 (1) 연안 냉수대해역, (2) 수온전선의 냉수대해역, (3) 동한난류해역, (4) 외해 냉수해역으로 구분할 수 있었다.

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OPC 및 GGBFS를 혼입한 콘크리트의 하중조건과 콜드조인트에 따른 내구수명 변화 (Changes in Service life in RC Containing OPC and GGBFS Considering Effects of Loadings and Cold Joint)

  • 김혁중;권성준
    • 한국건설순환자원학회논문집
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    • 제5권4호
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    • pp.466-473
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    • 2017
  • 콘크리트 구조물은 동일한 환경에 노출되었다 하더라도 하중특성과 콜드조인트 유무에 따라서 확산특성이 변화하고 이에 따라 내구수명이 변하게 된다. 본 연구에서는 기존의 선행연구를 분석하여 OPC 및 GGBFS를 사용한 콘크리트의 압축특성, 인장특성, 콜드조인트를 고려한 함수를 도출하였다. 경간 10.0m의 단순보를 가정하여 하중을 2.5kN/m에서 균열모멘트에 이르는 5.5kN/m까지 증가시키면서 내구수명을 평가하였다. 최대 하중에 이를 경우, 건전부 OPC 콘크리트의 경우 인장영역에서는 89.4%로, 압축영역에서는 101%로 내구수명이 변화하였으며, GGBFS 콘크리트의 경우 80.0%와 106%의 변화가 발생하였다. 콜드조인트의 경우 GGBFS를 사용한 콘크리트에서는 압축부에서는 82~80%로, 인장부에서는 69~61% 수준으로 크게 감소하였는데, 건전부의 확산계수가 OPC에 비하여 작지만 콜드조인트부의 확산성 증가가 상대적으로 크기 때문이다.

Verification on Cold-Tolerance of Some Fruit Trees as Species for Urban Greening Plants

  • Lee, Jin-Hee;Oh, Hee-Young;Kwon, O-Man
    • 한국환경과학회지
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    • 제26권10호
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    • pp.1155-1166
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    • 2017
  • This study selected commonly known species of fruit trees, and re-selected the species that endure the stress of extreme cold weather and physiologically restore themselves to the previous state until the following year. Then we could go ahead to propose the species that were appropriate as urban greening plants in weather condition of any part of the country. To do this, we conducted an experiments for six species of fruit trees based on the preference of the general public and recommendation of the experts; Morus alba (English name: mulberries), Diospyros kaki (English name: Persimmon), Prunus persia (English name: Peach), Elaeagnus umbellata var. coreana (English name: Korean Autumn Olive), Malus domestica 'Alps Otome' (English name: Alps Otome), and Prunus mume (English name: Blue Plum). The experiment verifies whether the trees survive without any stress from the cold weather under the national climate conditions (one in the suburbs of Seoul: Yongin city, one in the central Chungcheong region: Daejeon city, and in the southern Gyeongsang region: Jinju city in Korea). The experiment lasted for a year from August 2016 to August 2017. The levels of electrolytic efflux, chlorophyll content, plant height, fresh weight, and dry weight were measured four times (on August of 2016, January, February, and August of 2017) for each tree planted bare ground outdoors. Results showed that Diospyros kaki, Prunus persia, and Malus domestica 'Alps Otome' were proven durable and resistant to winters of all three areas (one in the suburbs of Seoul: Yongin city, one in the central Chungcheong region: Daejeon city, and in the southern Gyeongsang region: Jinju city in Korea). Especially, the increase of chlorophyll content and the reduction of electrolytic efflux were noticeable in Prunus persia than in the other two species, proving itself as the most cold-tolerant among the six species used in the experiment. In addition, interpreting from the physiological restoration data of one-year span before and after getting through winterer, Prunus persia was proven to be the most cold-tolerant species.

결흉(結胸)의 발병 부위에 대한 우재경(尤在涇)의 병리관 (Youzaijing's Pathologic View on the Outbreak Region of Chest Bind)

  • 조원준
    • 동의생리병리학회지
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    • 제22권4호
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    • pp.733-739
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    • 2008
  • It was said that the epigastric region was the outbreak region of chest bind on Shanghanlon. But successive medical men annotated the epigastric region as the chest, which caused the misunderstanding that chest bind was a chest trouble. However Youzaijing, a medical man in Qing dynasty, presented that the epigastric region meant stomach and the middle of stomach did intestines, comparing Dachengqi-tang with Daxianxiong-tang. This view agreed with Huatuo's six-region-transmutation theory. Taojiean and Zhangjingyue also criticized on the six-meridian-transmutation theory, proposing that the change of cold damage didn't go by the fixed rules. This reflected the oriental medical pathologic view that pathogen invaded and advanced to the weak region by the relations between healthy qi and pathogen, and it criticized on the doctrinarian interpretation of Shanghanlon as Neijing. Huatuo insisted that stomach was the final stage of cold damage by presenting that theory. And this theory became a philological basis on Youzaijing's pathologic view.

한국 남서해역에서 조석전선의 변동과 저수온역 확장기작 (Fluctuation of Tidal Front and Expansion of Cold Water Region in the Southwestern Sea of Korea)

  • 정희동;권철휘;김상우;조규대
    • 해양환경안전학회지
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    • 제15권4호
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    • pp.289-296
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    • 2009
  • 본 연구는 장기 해양관측(1966-1995)자료, 위성관측자료 및 수치모델기법을 이용하여 한국 남서해역에서 하계에 형성되는 조석전선괴 저수온역의 시공간적 변화를 파악하였다. 한국 남서 연안해역에서는 6월과 8월에 대흑산도~진도간 해역의 표면에서 주변 해역보다 $2{\sim}3^{\circ}C$ 낮은 저수온역이 분포하면서 조석전선역이 형성됨을 확인할 수 있었다. 수온수평경도가 $0.3^{\circ}C$/km 이상인 조석전선은 성층계수 2.0~2.5 범위이며, $0.03^{\circ}C$/km 이상인 저수온역은 성층계수 2.5~3.0의 범위와 일치하였다. 소조시에서 대조시까지 조석주기가 변하는 동안 조석전선의 위치변동은 전선은 25~75km, 저수온역의 범위는 60~90km로 조류의 세기에 정비례하여 이동 범위가 커지는 것으로 나타났다. 또한, 남서쪽 외해역으로 저수온역이 확장되는 원인은 진도 남서쪽으로 향하는 10cm/s 이상의 강한 조석잔차류에 의한 것으로 판단된다.

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Functional Analysis of Pepper Cys2/His-Type Zinc-Finger Protein Promoter Region in Response to Bacterial Infection and Abiotic Stresses in Tobacco Using Agrobacterium-Mediated Transient Assay

  • Kim, Sang-Hee;Hwang, Byung-Kook
    • The Plant Pathology Journal
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    • 제21권1호
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    • pp.39-46
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    • 2005
  • The promoter region flanking the 5’ CAZFP1 coding region was isolated from the genomic DNA of Capsicum annuum. To identify the upstream region of the CAZFP1 gene required for promoter activity, a series of CAZFP1 promoter deletion derivatives was created. Each deletion construct was analyzed by Agrobacterium-mediated transient transformation in tobacco leaves after infection by Pseudomonas syringae pv. tabaci, or treatment with methyl jasmonate (MeJA), ethylene, abscisic acid (ABA), salicylic acid (SA), cold and wounding. Promoter fragments of 685 bp or longer showed 7-fold or greater induction after P. s. pv. tabaci infection and MeJA treatment. The CAZFP1 full-length promoter (-999 bp) also showed 6-fold induction in response to ethylene. The transiently transformed tobacco leaves with the CAZFP1 full length promoter fused-GUS gene showed more than 5-fold induction in response to SA, ABA and cold. These results suggest that the CAZFP1 promoter contains responsive elements for pathogen, MeJA, ethylene, SA, ABA and cold.

Generation of a cold-adapted PRRSV with a nucleotide substitution in the ORF5 and numerous mutations in the hypervariable region of NSP2

  • Do, Van Tan;Dao, Hoai Thu;Hahn, Tae-Wook
    • Journal of Veterinary Science
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    • 제21권6호
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    • pp.85.1-85.6
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    • 2020
  • A cold-adapted porcine reproductive and respiratory syndrome virus (CA-VR2332) was generated from the modified live virus strain VR2332. CA-VR2332 showed impaired growth when cultured at 37℃ with numerous mutations (S731F, E819D, G975E, and D1014N) in the hypervariable region of the NSP2, in which the mutation S731F might play a vital role in viral replication at 30℃. Conserved amino acid sequences of the GP5 protein suggests that CA-VR2332 is a promising candidate for producing an effective vaccine against PRRSV infection. Further studies on replication and immunogenicity in vivo are required to evaluate the properties of CA-VR2332.

한반도에서의 지역에 따른 상이한 한파 발생 특징 (Regional Characteristics of Cold Surges over the South Korea)

  • 성현준;김백민
    • 대기
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    • 제30권3호
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    • pp.249-256
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    • 2020
  • We investigate regional differences in the characteristics of cold surges that occurred over the South Korea during winter season (December-February, 1981/1982~2017/2018). A significant regional contrast of cold surge characteristics exists and we found that this is closely related to the spatially inhomogeneous distribution of winter-mean climatological surface temperature in association with the complex topography of the Korean peninsula. For the regions of the temperature below -1℃ (Region1; R1), the frequency of cold surges is inversely proportional to the surface temperature almost linearly. In case of the regions above -1℃ (Region2; R2), cold surge frequency does not exhibit any clear dependency on the surface temperature. Duration and number of occurrences of cold surge between the two regions showed clear difference. Dynamical evolution of cold surges before the onset showed a sharp contrast between R1 and R2. In R1, cold surface air temperature (SAT) was already predominant over East-Asia before the onset and the cold temperature was sustained after the occurrence. On the contrary, warm SAT was predominant over East-Asia before the onset in R2. The SAT suddenly drops just after the cold surge occurrence. We present different origin of wave activity and propagation characteristics between the two types: Wave-activity flux (WAF) was relatively weaker and wave disturbances moved eastward in R1 along with the WAF mainly directing eastward. In case of R2, WAF was stronger and directing southeastward in the upstream of South Korea movement erasing predominant warmer air eventually causing sudden temperature drops over southern provinces over South Korea.