• Title/Summary/Keyword: cold wind

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Sea Surface Cold Water near the Southeastern Coast of Korea: Wind Effect (한국(韓國) 남동해안(南東海岸)부근의 해표면(海表面) 냉수(冷水) : 바람의 영향(影響))

  • Byun, Sang-Kyung
    • 한국해양학회지
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    • v.24 no.3
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    • pp.121-131
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    • 1989
  • Cold water observed at sea surface near the southeastern coast of Korea in summers 1982 and 1983 was studied by using data of hydrography, sea level, wind and satellite image. In summer season when water column shows 3-layered structure a "full" upwelling occurs by southwesterly transient wind continuing for several days. During upwelling event, surface water of high temperature moved offshore, middle water of low temperature outcropped to the sea surface, and sea level was lowered, however, equilibrium depth of surface layer was not changed. It may be concluded that cold water at the surface originates from middle layer and strong surface front is a result of surfacing of seasonal thermocline. In order to see the relationship between position of surface front and wind input, a model of Csanady (1982) was applied in a rigid lid approximation. The results show that frontal position can be determined by wind input and water structure near the southeastern coast of Korea. Cold water in summer can appear at the sea surface only when there is wind larger than a minimum wind impulse of order $10m^2/sec$.

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Power Quality Analysis of Wind-Diesel Hybrid Generation System Installation Area (복합발전 풍력-디젤 하이브리드 시스템 설치 지역의 전력품질 분석)

  • An, Hae-Joon;Kim, Hyun-Goo;Kim, Seok-Woo;Ko, Seok-Whan;Jang, Gil-Soo
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.06a
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    • pp.539-541
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    • 2009
  • A severely cold weather condition of King Sejong Station, Antarctica becomes a very severe condition for an installation/operation of wind generation system. When the existing wind generation system works, it may cause a damage and destruction of wind generation system and can bring about big problems in terms of the power quality. Accordingly, it is essential to obtain technologies for the installation and operation of small wind generation system for the polar region's wind generation, and to assess and demonstrate the performance in the severely-cold environment and the polar wind generation system's development, supplementation, alteration. Also, as the available power of King Sejong Station, Antarctica, the diesel generator has been mainly used, and the wind generator has been used in the hybrid form. Wind generation and diesel generation has the different load following control each other. In the wind generation, the generated power very rapidly changes according to the change of the velocity of the wind. On the other hand, the diesel generation shows very gentle change in the velocity of output. Therefore, the study is intended to analyze the 10kw small wind generator-diesel generator's power quality of King Sejong Station, Antarctica, which is the hybrid system installation area.

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Study on Application of Herba Ephedrae Main Blended Prescription from Dongeuybogam (동의보감(東醫寶鑑) 중(中) 마황(麻黃)이 주약(主藥)으로 배오(配伍)된 방제(方齊)의 활용(活用)에 대한 고찰(考察))

  • Hwang, Chi-Hwan;Yun, Young-Gab
    • Herbal Formula Science
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    • v.13 no.2
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    • pp.169-192
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    • 2005
  • This report describes the remedial fields, symptoms, pathlogy, dosage, prescriptional constitution of 79 studies to the use of Herba Ephedrae main blended prescriptions from dongeubogam. The following conclusions were reached through investigations on the prescriptions that use Herba Ephedrae as a key ingredient Herba Ephedrae blended prescriptions are utilized for 26 therapeutic purposes, for example, in symptoms of cough, cold, wind. In particular, 20.2% of the prescriptions appear in the chapter of cough. Prescriptions that utilize Herba Ephearae as the main ingredient are used in the treatment of 47 different types of diseases, for example, in the treatment of wind-cold pathogen, cold, wind, exogenous febrile disease etc. Herba Ephedrae is most widely used in six pathogenic factors such as wind, cold, dampness, heat. The actual amount of Herba Ephedrae blended has ranged at a wide variety of amounts from 1 don to 2 don. It is widely applied with base prescriptions such as Mahwang-tang, Samyo-tang, Mahwangbujasesin-tang, Mahwangkanghwal-tang.

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A Study on Application of Radix Asari Main Blended Prescription From Dongeubogam (동의보감(東醫寶鑑) 중(中) 세신(細辛)이 주약(主藥)으로 배오(配伍)된 방제(方劑)의 활용(活用)에 대한 고찰(考察))

  • Jeon Ho-Cheol;Rho Euy-Joon;Kim Hyung-Rul;Yun Young-Gab
    • Herbal Formula Science
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    • v.12 no.2
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    • pp.57-76
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    • 2004
  • This report describes the remedial fields, symptoms, pathology, dosage, prescriptional constitution of 69 studies related to the use of Radix Asari main blended prescriptions from Dongeubogam. The following conclusions were reached through investigations on the prescriptions that use Radix Asari as a key ingredient. Radix Asari blended prescriptions are utilized for 14 therapeutic purposes, for example, in symptoms of tooth, eye, paralysis, ear-nose, skin infection and carbuncle. In particular, 14.49% of the prescriptions appear in the chapter of tooth, and 10.14% of those appear in the chapter of eye. Prescriptions that utilize Radix Asari as the main ingredient are used in the treatment of dental disease, othalmology, nose and ear disease, throat disease, common cold, dermothology, paralysis, musculoskeletal disease, disease of the head, asthma, genital disease, the injury of the cuts and they are also used for treating 50 different types of diseases. Radix Asari is used in Six pathogenic factors such as wind, wind-cold, wind-heat, wind-dampness heat, wind-dampness, dampness, paralysis, cold-chill, cold, dryness, in visceral pathogenic factors such as stomach, kidney, liver-kidney, liver and in chi-blood pathogenic factors such as chi-blood deficiency, chi-blood stagnation and in extravasated blood pathogenic factors such as impact injury, an injury such as cuts, blood accumulation as well as weakness-cold and parasites. The actual amount of Radix Asari blended has ranged at a wide variety of amounts from 2.5pun(about 0.94gram) to 3don(about 11.25gram). 26.09% of the prescriptions used 1don(about 3.75gram). The function of Radix Asari is to calm down, to get the consciousness back, to bore through, to warm up the meridians and to run it smoothly, to discharge of phlegm from the combination of drugs and prescriptions.

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Methodology of Climate-Ecological Priority Area Analysis for Air Corridor Planning - In the Case of Pan-Gyo Area - (바람통로 계획을 위한 기후생태적 우선지역 분석 및 설정 방법 - 성남 판교지역을 중심으로 -)

  • 송영배
    • Journal of the Korean Institute of Landscape Architecture
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    • v.31 no.3
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    • pp.58-73
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    • 2003
  • It is well known that urban environment affects climate, as we can see in the quality of bio-climate. However, climate has not been recognised properly in the urban planning process. The role it flays needs to be examined for better urban environment. The main objective of this study is to investigate the climate-ecological priority area which produces cold fresh air and thermal induced wind circulation between rural and urban areas. The objective is also to improve the quality of bio-climate and wind circulation at blocked urban areas. This paper uses the measurement and analysis method of wind direction and wind speed in order to investigate the climate-ecological priority area and cold fresh air corridor. In this study, local climate conditions i.e. wind speed, wind direction, temperature, humidity etc., were measured at nine fields and analyzed. On the basis of the climate measurement, the climate ecological priority areas were delineated; These will be assigned as climate-ecological conservation areas.

Effect of Flue Gas Heat Recovery on Plume Formation and Dispersion

  • Wu, Shi Chang;Jo, Young Min;Park, Young Koo
    • Particle and aerosol research
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    • v.8 no.4
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    • pp.161-172
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    • 2012
  • Three-dimensional numerical simulation using a computational fluid dynamics (CFD) was carried out in order to investigate the formation and dispersion of the plume discharged from the stack of a thermal power station. The simulation was based on the standard ${\kappa}{\sim}{\varepsilon}$ turbulence model and a finite-volume method. Warm and moist exhaust from a power plant stack forms a visible plume as entering the cold ambient air. In the simulation, moisture content, emission velocity and temperature of the flue gas, air temperature and wind speed were dealt with the main parameters to analyze the properties of the plume composed mainly of water vapor. As a result of the simulation, the plume could be more apparent in cold winter due to a big difference of latent heat capacity. At no wind condition, the white plume rises 120 m upward from the top of the stack, and expands to 40 m around from the stack in cold winter after flue gas heat recovery. The influencing distance of relative humidity will be about 100 m to 400 m downstream from the stack with a cross wind effect. The decrease of flue gas temperature by heat recovery of thermal energy facilitates the formation of the plume and restrains its dispersion. Wind speed with vertical distribution affects the plume dispersion as well as the density.

Numerical Simulation of Upwelling Appearance near the Southeastern Coast of Korea (한국 남동 연안역의 용승현상에 관한 수치실험)

  • Kim, Dong-Sun;Kim, Dae-Hyun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.14 no.1
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    • pp.1-7
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    • 2008
  • To investigate the appearance of cold water by upwelling effect near Ulsan-Gampo of the southeastern coast in Korea on June, 1999, we carried out a numerical experiment by 3-dimensional diagnostic numerical model. Appearance of cold water by the result of numerical experiment was due to upwelling by wind effect at 50-100m depth near Ulsan-Gampo coast. This result was mused by using a model to 2 times of existing wind magnitude near Busan, Ulsan and Gampo that is 5.0m/sec wind. Therefore, to illustrate the phenomenon of extraordinary marine environment like upwelling event and so forth, appropriate wind data at sea should be used instead of those on land.

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The Wind Effect on the Cold Water Formation Near Gampo-Ulgi Coast (감포-울기 연안해역에서 발생하는 냉수대 현상과 해상풍과의 관계)

  • LEE Dong-Kyu;KWON Jae-Il;HAHN Sang-Bok
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.31 no.3
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    • pp.359-371
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    • 1998
  • The cold water event near Gampo-Ulgi coast in summers between 1987 and 1994 are studied using sea surface temperature records at the coastal stations, ocean winds measured by SSM/I and AVHRR SST images. The response time of the cold water events by upwelling is less than two days and surface cold water expands up to the Ulleung Island. An analysis of 61 upwelling favorable winds indicates that the surface water temperature drops more than $1^{\circ}C\;in\;80\%$ of the south-westerly wind events. The linear correlation coefficient between wind impulses and the maximum temperature drops is good (0.6). It is found that the major cause of the cold water events is the along-shore wind in summer. The bottom topography and off-shore direction of the East Korean Warm Current by the potential vorticity conservation near Gampo coast also contribute the formation of the cold water along the southeast coast of Korea.

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Modification of Sea Water Temperature by Wind Driven Current in the Mountainous Coastal Sea

  • Choi, Hyo;Kim, Jin-Yun
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2003.11a
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    • pp.177-184
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    • 2003
  • Numerical simulation on marine wind and sea surface elevation was carried out using both three-dimensional hydrostatic and non-hydrostatic models and a simple oceanic model from 0900 LST, August 13 to 0900 LST, August 15, 1995. As daytime easterly meso-scale sea-breeze from the eastern sea penetrates Kangnung city in the center part as basin and goes up along the slope of Mt. Taegullyang in the west, it confronts synoptic-scale westerly wind blowing over the top of the mountain at the mid of the eastern slope and then the resultant wind produces an upper level westerly return flow toward the East Sea. In a narrow band of weak surface wind within 10km of the coastal sea, wind stress is generally small, less than l${\times}$10E-2 Pa and it reaches 2 ${\times}$ 10E-2 Pa to the 35 km. Positive wind stress curl of 15 $\times$ 10E-5Pa $m^{-1}$ still exists in the same band and corresponds to the ascent of 70 em from the sea level. This is due to the generation of northerly wind driven current with a speed of 11 m $S^{-1}$ along the coast under the influence of south-easterly wind and makes an intrusion of warm waters from the southern sea into the northern coast, such as the East Korea Warm Current. On the other hand, even if nighttime downslope windstorm of 14m/s associated with both mountain wind and land-breeze produces the development of internal gravity waves with a hydraulic jump motion of air near the coastal inland surface, the surface wind in the coastal sea is relatively moderate south-westerly wind, resulting in moderate wind stress. Negative wind stress curl in the coast causes the subsidence of the sea surface of 15 em along the coast and south-westerly coastal surface wind drives alongshore south-easterly wind driven current, opposite to the daytime one. Then, it causes the intrusion of cold waters like the North Korea Cold Current in the northern coastal sea into the narrow band of the southern coastal sea. However, the band of positive wind stress curl at the distance of 30km away from the coast toward further offshore area can also cause the uprising of sea waters and the intrusion of warm waters from the southern sea toward the northern sea (northerly wind driven current), resulting in a counter-clockwise wind driven current. These clockwise and counter-clockwise currents much induce the formation of low clouds containing fog and drizzle in the coastal region.

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Nocturnal Surface Cooling and Cold Air Transport Analysis Based on High Density Observation - A Case Study of Eunpyeong New Town in Seoul (고밀도 관측자료를 이용한 야간 지면냉각과 찬공기 이동 분석 - 서울 은평구 뉴타운 사례)

  • Yi, Chae-Yeon;Kim, Kyu-Rang;Choi, Young-Jean;Won, Hye-Young;Scherer, Dieter
    • Journal of the Korean Association of Geographic Information Studies
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    • v.15 no.4
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    • pp.124-137
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    • 2012
  • Climate analysis is important in urban planning for human comfort. Synoptic weather conditions can only resolve the 30% of local variance of wind conditions whereas 70% of the variance arise from local terrain, buildings, and other small scale thermal conditions. Climate Analysis Seoul (CAS) was developed to resolve such micro-scale climate. The Local-scale air temperature Deviation (LD) analysis map from CAS showed the co-existence of built-up and suburban areas in the study region (CR, Cold-air analysis Region) despite its small extent. Temperature, humidity, wind speed, and wind direction were monitored in CR. Hourly observed cooling rate agreed well with LD. Cold air production, transportation, and stagnation was visualized by the observed Vertical Temperature Gradient (VTG) along the small stream in CR. VTG observed at the upper-most stream can be divided into two components: radiative cooling and cold air inflow from outside. Radiative cooling exists regardless of the wind speed whereas cold air inflow occurs only with calm wind. From the regression analyses based on the wind speed, the inflow portion was determined as 84% of radiative cooling. Climate analysis in the future will be able to characterize the changes in cold air by urban development plan to support the human comfort.