• Title/Summary/Keyword: cold environment

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Global and Korean Peninsula Climate Changes and Their Environmental Changes

  • Yi, Hi-Il;Shin, Im-Chul
    • The Korean Journal of Quaternary Research
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    • v.21 no.2
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    • pp.74-76
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    • 2007
  • The modern foraminiferal distribution patterns and species diversity in surrounding seas of Korea are controlled by winter monsoon and characteristics of water masses. Abrupt climate change, Younger Dryas cold episode" is identified in Korea. The Younger Dryas is characterized by local extinctions of foraminifera. Several record-breaking climate phenomena observed in Korea, especially September, 2007.

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Comparison of Cold Vapor Atomic Absorption Spectrophotometry Analysis and EPA Method 101A for Measurement of Mercury in the Flue Gas (배출가스중 수은 측정을 위한 환원기화 원자흡광광도법과 EPA Method 101A의 비교 연구)

  • 김경희;최양일;박일수;홍지형;차준석;석광설;김대곤
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 1999.10a
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    • pp.92-93
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    • 1999
  • 수은은 상온에서 액체상태로 존재하는 유일한 금속으로서, 증기압이 매우 높기 때문에 가장 쉽게 휘발될 수 있는 중금속이다. 다른 중금속들은 거의 입자 상태로 변환되기 때문에 전기 집진기 등과 같은 일반적인 입자 제어시설에서 98%이상이 제거되지만, 증기압이 매우 높은 수은은 다단계 습식 스크러버, 활성탄을 사용하는 전기집진기/습식 스크러버가 결합된 특정한 방지시설에 없는 한 거의 대부분이 그대로 배출된다.(중략)

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Paper Preparation for The $5^{th}$ Rolling Conference 'Development of new emulsification system rolling oil' (신규 유화 System 압연유의 개발)

  • MINABE TATSURO
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2004.08a
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    • pp.268-276
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    • 2004
  • As recent demands for cold rolling oil for steel, not only better lubricity, but cost reduction and improvement of work environment are increasingly required. In order to respond these demands, Nihon Parkerizing has developed rolling oils with completely new emulsification system. Comparing with conventional oils, the new system indicates better iron fine removability to maintain oil concentration, due to better iron fine dispersion, and superior mill stain resistance by spray stain test.

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A Study on Local Three-Dimensional Visualization Methodology for Effective Analysis of Construction Environments in Extreme Cold Regions (효과적인 극한지 건설환경 분석을 위한 현지 3차원 가시화 방안 연구)

  • Kim, Eui Myoung;Lee, Woo Sik;Hong, Chang Hee
    • Spatial Information Research
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    • v.20 no.6
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    • pp.129-137
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    • 2012
  • For construction project in extreme cold region, it is essential to establish basic data on the site such as topographical data from the early stage of construction of planning and designing, and it is needed to frequently perform site investigation when necessary. However, extreme cold regions are characteristic of being at long distance and difficult in approaching, and special regions such as Antarctica, in particular, are hard to conduct site investigation. Although a site investigation may be conducted, those who can visit Antarctica are sufficiently limited so that most of the staff may participate in construction without knowledge of the site and increase the risk of errors in decision making or designing. In order to resolve such problems, the authors in this study identified methods of building wide-area topographical data and bedrock classification data of exposed areas via remote sensing and of building precise topographical data on the construction site. Also, the authors attempted to present methods by which such data can be managed and visualized integrally via three-dimensional GIS technology and all the participants in construction can learn sense of field and conduct necessary analysis as frequent as possible. The areas around the Jangbogo Antarctic Station were selected to be the research area for conducting effective integrational management and three-dimensional visualization of various spatial data such as wide-area digital elevation model, ortho-images, bedrock classification data, local precise digital elevation model, and site images. The results of this study may enable construction firms to analyze local environments for construction whenever they need for construction in extreme cold regions and then support construction work including decision making or designing.

A Study on the Fuel Quality Characteristics and Cold Weather Performance Test for Biodiesel Derived from Microalgae (미세조류 유래 바이오디젤 품질 특성 및 차량 저온 성능평가 연구)

  • JEON, CHEOL-HWAN;PARK, CHEON-KYU;LIM, JAE-HYUK;RYU, YOUNG-JIN;YANG, JI-HYUN;SHIM, SANG-HYEOK;CHO, YONG-HEE;KIM, KI-HYUN;PARK, HANWOOL;KIM, JUN-HO;PARK, JAEHOON;JUNG, INJAE;KANG, SUNG-MO;SHIN, DONG-WOO;LIM, SANG-MIN;LEE, CHOUL-GYUN;NA, BYUNG-KI
    • Journal of Hydrogen and New Energy
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    • v.28 no.5
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    • pp.545-553
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    • 2017
  • Microalgae can offer an attractive way of generating renewable and sustainable biodiesel. Biodiesel derived from microagae can have lower impact on the environment and food supply than biodiesel produced from crops. But biodiesel derived from microagae have poor fuel properties at low temperature depending on their species. In this study, it was investigated that fuel characteristics of biodiesel derived from Tetraselmis sp. and cold weather performance of biodiesel blend (BD3, 3 vol.% biodiesel - 97 vol.% diesel). The startability and operability of the passenger car in BD3 was good at $-20^{\circ}C$.

Study on Rice Growing Environment Against Cold Sea Wind in Eastern Coastal Area of Korean Peninsula (동해안 냉해풍지역의 벼 생육환경 연구)

  • Kim, Jeong-Il;Lee, Ji-Yoon;Park, Dong-Soo;Park, No-Bong;Kwon, Oh-Deog;Chang, Jae-Ki;Lee, Ji-Hun;Kim, Sang-Yeol;Kang, Hang-Won
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.55 no.2
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    • pp.133-138
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    • 2010
  • This study was conducted to analysis a major cause of rice yield reduction in 4 research points, 1, 2, 3, and 5km, from coastline in the East Sea. There were great changes of temperature in each research point, though the average temperature a day was no difference between each research point. Each temperature in 1, 2, and 3km research points was 8, 7, and $4^{\circ}C$ lower than in 5km when cold salty wind was generated due to cold pool. As it was close in coastline, its soil was abundant sand components, little silt and clay soil components and lacking in cation exchange capacity(CEC). And plant height became a smaller, heading date was delayed for 3~4 days, and dry weight was reduced. Also, it was to be down percent of fertile grain. As cultivation site was close in seaside, its decline was larger because of reduction of panicle number per hill. It was "Samdeogbyeo" that was variety adapted in cold salty wind, having yield potential more than 90% in 2km.

Comparison of Grazing Characteristics of a Freshwater Bivalve Unio douglasiae (Unionidae) on the Cold and Warm Phytoplankton Communities in Eutrophic Lake (부영양호수의 저온기와 고온기 식물플랑크톤에 대한 말조개의 섭식능 비교)

  • Lee, Song-Hee;Baik, Soon-Ki;Hwang, Soon-Jin;Kim, Baik-Ho
    • Korean Journal of Ecology and Environment
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    • v.42 no.1
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    • pp.115-123
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    • 2009
  • Grazing effects of a freshwater bivalve, Unio douglasiae, on both the phytoplankton communities of cold- and warm eutrophic lakes were examined in aquarium with sediment. The animal U. douglasiae used in the study was collected from the Gunsan (Jeonbuk), acclimatized in laboratory aquaria with washed sand from the mussel collection stream, and starved for $2{\sim}3$ days by the experiment. Grazing experiments were performed with the surface waters collected from Lake Ilgam (Seoul) in the cold period (March 31, 2008), and the warm period (June 19, 2008), respectively. Results clearly showed that the concentration of chlorophyll-a (chl-a) and algal abundance were decreased with the increase of mussel-treated density and treated-time. At the same animal density, U. douglasiae effectively decreased the chl-a of cold-lake water (CW), compared to warm-lake water (WW). Increasing the mussel density, the filtering rate (or algal abundance) of the mussel on the CW gradually decreased, while those of WW did not increase or decrease. Major phytoplankton species Synedra ulna and Stephanodiscus hantzschii, and Scenedesmus ecornis in CW, and those of Tetraedron regulare and Pediastrum simplex in WW, were quickly decreased after the mussel stocking. Interestingly, cyanobacterium Microcystis aeruginosa in WW, not dominant species, were less removed. These results suggest that a freshwater bivalve U. douglasiae have a strategic potential to control dense hibernal diatom or green algae, rather than the cyanobacterial bloom in eutrophic water.

LCD BLU Defects Detection System with Sidelight (측면조명을 이용한 LCD 백라이트 불량검출 시스템)

  • Moon, Chang-Bae;Bark, Jee-Woong;Lee, Hae-Yeoun;Kim, Byeong-Man;Shin, Yoon-Sik
    • The KIPS Transactions:PartB
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    • v.17B no.6
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    • pp.445-458
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    • 2010
  • A Cold Cathode Fluorescent Lamp(CCFL) is used as a LCD Monitor's backlight widely. The most common way to check CCFL's defects is an examination with the naked eye. This naked eye examination can cause examination inconsistencies and industrial disasters. A shooting environment and detection algorithms are important for finding CCFL defects automatically. This paper presents CCFL defect detection algorithms using images captured under the shooting environment with sidelight which is one of the shooting environment we have suggested. The experimental result shows 4.65% of overdetection and 5.37% of unsuccessful defect detection of CCFL.

Study on Farm Work Environment and Physical Load in Korea - Focused on Farm Work Model by Crops - (한국의 농작업환경과 인체부담에 관한 연구(III) - 작목별 농작업 모형을 중심으로 -)

  • 최정화;안옥선;황경숙
    • Korean Journal of Rural Living Science
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    • v.10 no.2
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    • pp.85-100
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    • 1999
  • This study was to get basic data for the establishment of proper labor counterplan so that we estimated farm work volume and work loads by crops. We examined the method of work practices such as a work posture, work time, measured work environment such as hot, cold, humidity and ultraviolet rays and calculated physical loads induced by them. Also we surveyed work environment, work posture, sleeping time and work time because they affect on farmer's health. Farmer's health survey was investigated by questionnaire and measured farmer's physical load. The types of farm work were classified into greenhouse farming, rice farming, dry field farming, stock farming and special crop farming. 11 crops were selected, for example, greenhouse melon, riceㆍred pepper, milky cow farming, pear, grapes, dropwort, sweet potato, potato, radish, and cabbage. We also chose subject districts haying the most yield of 11 crops. Our survey was conducted for the period when farmers think the hardest period in physical work load. The farm work models based on work standard were presented according with farmer's health.

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