• 제목/요약/키워드: Temperature Trend

검색결과 1,284건 처리시간 0.03초

Simulation of the Mixed Layer in the Western Equatorial Pacific Warm Pool

  • Jang, Chan-Joo;Noh, Yign
    • Ocean and Polar Research
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    • 제24권2호
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    • pp.135-146
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    • 2002
  • The upper ocean in the western equatorial Pacific warm pool during TOGA-COARE IMET IOP was simulated using a one-dimensional turbulence closure ocean mixed-layer model, which considered recent observations, such as the remarkable enhancement of turbulent kinetic energy near the ocean surface. The shoaling/deepening of the mixed layer and warming/cooling subsurface water in the model were in reasonable agreement with the observations. There was a significant improvement in simulating the cooling trend of the sea surface temperature under a westerly wind burst with heavy rainfall over previous simulations using bulk mixed-layer models. By contrast the simulated sea surface salinity (SSS) departed significantly from the observed SSS, especially during a westerly burst and the subsequent restratification period, which might be due to 3-D control processes, such as downwelling/upwelling or advection.

다기능성 나노자성복합소재 기술동향 (Technical Trend of Multi-function for Nano-magnetic Material)

  • 김유상
    • 한국표면공학회지
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    • 제45권1호
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    • pp.43-52
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    • 2012
  • Recently, it has been developed for Eco-environment, Super light, Multi-functional nano materials. As needed mobile parts in Smart phone or TV, computer, information communication for high pass signal, multi-function, Magnetic thin film materials have been developed. As last, magnetic powder, sintered and sputtering parts were thick and low purity than electroplating layer, low pass signal and noise were resulted, vibrated TV screen. Because chemical complex temperature was high and ununiform surface layer, it has been very difficult for data pass in High Frequency (GHz) area. Large capacity data pass is used to GHz. Above GHz, signal pass velocity is dependent on Skin Effect of surface layer. If surface layer is thick or ununiform, attachment is poor, low pass signal and cross talk, noise are produced and leaked. It has been reported technical trend of Electrochemically plating and Surface treatment of Metal, Polymer, Ceramic etc. by dispersion/complex for Multi functional nano-magnetic material in this paper.

CD 동향기록 시스템 개발 (The Development of CD Trend Recording System)

  • 장미혜;윤갑구;최항섭;이승재
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 하계학술대회 논문집 B
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    • pp.465-467
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    • 1997
  • The CD Trend Recorder, developed as a substitution of the existing SCR (Stript Chart Recorder), acquires various outputs (e.g. frequency voltage, current, power, temperature, pressure, etc) simultaneously using PC up to 32 different outputs, display, and analyze them just like the existing SCR. It stores the data in CD-ROM so th various data can be stored permanently this system has built-in MMI program and to monitor and analyze the data in real-t expert system link the data to the do where needs the data to display, analyze, in the new medium at the same time.

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Technology Trend and Requirement of Mobile Displays Using Low-Temperature Poly-Si (LTPS) Technologies

  • Kwon, Oh-Kyong
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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    • pp.409-412
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    • 2007
  • A lot of research for system-on-panel(SOP) have been done to integrate display systems including data driver, gate driver, timing controller, DC-DC converter, and smart functions such as embedded touch screen, ambient brightness sensing and luminance control, finger printing on the glass. Recently, the cost of an one-chip driver IC with various functions has decreased rapidly, and new mobile display interface technologies have been introduced. So it is necessary to examine the feasibility of SOP for practical mobile applications. In this paper, we will re-examine LTPS technologies for mobile displays in terms of various aspects and discuss the practical limitations on SOP technology and future technology trend of mobile displays.

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Long-term Sediment Discharge Analysis in Yongdam Dam Watershed due to Climate Change

  • Felix, Micah Lourdes;Kim, Joocheol;Choi, Mikyoung;Jung, Kwansue
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2020년도 학술발표회
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    • pp.327-327
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    • 2020
  • Increase in Earth's surface temperature, higher rainfall intensity rate, and rapid changes in land cover are just some of the most evident effects of climate change. Flooding, and river sedimentation are two inevitable natural processes in our environment, and both issues poses great risks in the dam industry when not addressed properly. River sedimentation is a significant issue that causes reservoir deposition, and thus causes the dam to gradually lose its ability to store water. In this study, the long-term effects of climate change on the sediment discharge in Yongdam Dam watershed is analyzed through the utilization of SWAT, a semi-distributed watershed model. Based from the results of this study, an abrupt increase on the annual sediment inflow trend in Yongdam Dam watershed was observed; which may suggests that due to the effects of climate change, higher rainfall intensity, land use and land cover changes, the sedimentation rate also increased. An efficient sedimentation management should consider the increasing trend in sedimentation rate due to the effects of climate change.

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최근 8-9월의 기상특징과 기후생산력지수의 변화 (Change of Climatic Productivity Index for Rice under Recent Climate Change in Korea)

  • 심교문;김용석;정명표;최인태
    • 한국농림기상학회지
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    • 제16권4호
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    • pp.384-388
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    • 2014
  • 과거 12년동안(2001~2012년)의 벼 등숙기간인 8~9월의 기상변화 특징은 기온이 높아지고 일조시간이 줄어드는 경향이었다. 이와 같은 벼 등숙기간의 고온과 일조시간의 부족은 벼 기준의 기후생산력지수(CPI)의 감소의 원인이었고, 감소의 정도는 벼 출수기가 빠를수록 더 크게 나타나는 것으로 분석되었다. 따라서, 안정적인 벼생산량을 확보하기 위해서는 벼 출수기를 늦추는 재배적인 조치가 필요할 것으로 판단되었다. 그리고, 과거 12년동안의 벼 수량의 변화는 특별한 경향을 나타내지는 않았으나, 벼 수량의 연간 변화는 CPI의 연간 변화와 유사한 패턴을 보였다. 특히, 출수기가 8월 11일 조건에서, 벼 수량에 대한 CPI의 일차함수는 전국 벼 수량 변이의 63%정도 설명하는 것으로 분석되었다.

A Study on the Properties of Silk and Nylon 6 Fabrics by Tannic Acid Treatment

  • Yoa, Soojin;Kim, Jongjun
    • 패션비즈니스
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    • 제20권3호
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    • pp.119-132
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    • 2016
  • Weighting of silk fabrics have long been practiced in silk fabric trading based on the primary consideration of price-weight, and secondary one of quality improvement in handle, luster, and drape properties. Recent trend of practicing weighting of silk fabrics is, however, focused on the improvement of the handle, luster, drape, and other properties. During the finishing processes of synthetic fiber, nylon, comprising amide structure, include the use of tannic acid, especially in the dyeing. A multitude of studies are being implemented in terms of improving fastness to washing, fastness to light of dyed nylon product, or the light fastness of nylon 6 itself. In this study, the effects of various tannic acid treatments on the physical properties related to the handle of nylon 6 and silk fabrics are examined and reviewed. The effects of treatment condition of the tannic acid, e.g., the concentration of the aqueous tannic acid solution, treatment time, and temperature were investigated. As the concentration of the aqueous solution of tannic acid increased, the bending rigidity values of the silk and nylon 6 fabrics increased. The treated fabrics felt stiff to the touch. Within the mild conditions of bending employed in the bending measurement of KES, nylon 6 treated fabric specimen exhibited a trend of improvement of bending resiliency within the range of small bending deformation. The weight of treated fabrics have all increased. The air-permeability values decreased as the treatment concentration increased. However, the decrease tendency of air permeability values may be alleviated by adjusting the fabric count during the tentering or expanding processes, either by tension adjustment or heat treatment. Optimum conditions of the treatment for nylon 6 are 1.25% tannic acid concentration, bath temperature of $85^{\circ}C$, pH 3.1, and those for silk fabric treatment are 1.25% tannic acid concentration, bath temperature of $85^{\circ}C$, pH 3.1. The treatment conditions will lead to the improvement in the properties of fabrics for summer.

Climate Change Concerns in Mongolia

  • Dagvadorj, D.;Gomboluudev, P.;Natsagdorj, L.
    • 한국제4기학회지
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    • 제17권2호
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    • pp.47-54
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    • 2003
  • Climate of Mongolia is a driven force on natural conditions as well as socio-economic development of the country. Due to the precariousness of climate conditions and traditional economic structure, natural disasters, specially disasters of meteorological and hydrological origin, have substantial effect upon the natural resources and socio-economic sectors of Mongolia. Mongolia's climate is characterized by high variability of weather parameters, and high frequency and magnitude of extreme climate and weather events. During the last few decades, climate of the country is changing significantly under the global warning. The annual mean air temperature for the whole territory of the country has increased by $1.56^{\circ}C$ during the last 60 years,. The winter temperature has increased by $1.56^{\circ}C$. These changes in temperature are spatially variable: winter warming is more pronounced in the high mountains and wide valleys between the mountains, and less so in the steppe and Gobi regions. There is a slight trend of increased precipitation during the last 60 years. The average precipitation rate is increased during 1940-1998 by 6%. This trend is not seasonally consistent: while summer precipitation increased by 11 %, spring precipitation decreased by 17. The climate change studies in Mongolia show that climate change will have a significant impact on natural resources such as water resources, natural rangeland, land use, snow cover, permafrost as well as major economic activities of arable farming, livestock, and society (i.e. human health, living standards, etc.) of Mongolia. Therefore, in new century, sustainable development of the country is defined by mitigating and adaptation policies of climate change. The objective of the presentation is to contribute one's idea in the how to reflect the changes in climate system and weather extreme events in the country's sustainable development concept.

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1990년대 중·후반을 전후한 북반구 여름철 열대-중위도 원격상관의 장기 변화 (Interdecadal Changes in the Boreal Summer Tropical-Extratropical Teleconnections Occurred Around Mid-to-late 1990s)

  • 이준이
    • 대기
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    • 제28권3호
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    • pp.325-336
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    • 2018
  • This study investigates robust features of interdecadal changes in the Northern hemisphere summer tropical-extratropical teleconnection occurred around the mid-to-late 1990s by analyzing four different reanalysis data for atmospheric circulation and temperature, two precipitation reconstructions, and two sea surface temperature (SST) data during the satellite observation era of 1980~2017. For the last 38 years, there has been a significant increasing trend in anticyclonic circulation at lower and upper troposphere and 2 m air temperature with wavenumber-5 Rossby wave structure in the Northern Hemisphere (NH) extratropics. The increase has been accompanied with the significant weakening and northward shift of jet stream over Eurasia and the North Pacific. It is further found that there has been a significant interdecadal shift occurred around the mid-to-late 1990s in the two distinct modes of tropical-extratropical teleconnection: Western Pacific-North America (WPNA) and circumglobal teleconnection (CGT) pattern. After mid-to-late 1990s, the WPNA has played more important role in modulating the extratropical atmospheric circulation and surface climate, which has been preferentially occurred during the El $Ni{\tilde{n}}o$-Southern Oscillation (ENSO) decaying or transition summer such as 1998, 2010 and 2016. During these summers, severe heat waves were occurred over many parts of the NH extratropics due to the combined effect of the increasing trend in the barotropic anticyclonic circulation and the significant WPNA across the NH. Although weakened, the CGT also contributed to some of hot summers over many parts of the NH extratropics such as 1999, 2000, 2008, 2011, and 2012 when weak to moderate La $Ni{\tilde{n}}o$ was persisted.

어선용 수평 냉각판 냉동장치의 냉동 효율 개선에 관한 연구 (A Study on Freezing Efficiency Improvement of Horizontal-Plate Freezer for Fishing Vessel)

  • 이재철;정지호;김병목;신성철;김수영;정보용
    • 대한조선학회논문집
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    • 제52권1호
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    • pp.19-24
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    • 2015
  • The economic efficiency for fishery products can be related to their freshness and the quality. In order to freshly storage the product, freezing equipment system is necessary for fishing vessels. For this purpose, the horizontal plate freezer (HPF) is mostly used. In this research, our major objective is to improve the freezing performance of the HPF. Therefore, it is important to analyse the relationship between the shape of channels and the cooling temperature of the HPF. In order to save calculation time while checking the trend analysis between shape and performance, we used scaled models, and evaluate the cooling temperature of full scale model based on trend analysis results. The produced HPF in domestic was used, and the same operating conditions are considered. Based on this paper, the future research will be a comparison and verification through the experiments.