• Title/Summary/Keyword: Weather characteristic

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Design standard for fairway in next generation

  • Ohtsu, Kohei;Yoshimura, Yasuo;Hirano, Masayoshi;Takahashi, Hironao;Tsugane, Masanori;Ohtsu, Kohei
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2006.10a
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    • pp.230-239
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    • 2006
  • The depth, width and alignment of fairway that are main port water facilities should be designed considering the various elements including particulars of design ships, weather and sea conditions around fairway and method of ship-handling. However not only the existing Japanese design standard for fairway and also those of other countries do not take into consideration of such kind of elements and no design standard is made by quantitative analysis. In this circumstance the new design standard (Approach Channels, A Guide for Design) depending on classified various elements and quantitative analysis was proposed in 1997 by PIANC and IAPH. But it was proved that calculated values according to this standard were unfounded and had some problems to output the discontinuous value by small difference of calculation condition because the each value fur each element was simply added. And also it is hard to apply this standard to the design of port water facilities in Japan because this [A Guide for Design] is the design standard for long channels in European port. The proposal of more reasonable Japanese standard will be expected by applying the study result of naval architecture and navigation and by the cooperation of ship operators to use fairway, naval architects to built ships and civil engineers to dredge fairway. The concept of a fairway in 'Design standard fur fairway in next generation' is defined as passage for approach channel) and traffic lane designated by light buoys as navigable water for safe navigation. In 'Design standard for fairway in next generation' depth, width and alignment are picked up among many design elements of a fairway. Design method for those elements is shown based on design ships and navigational environments. This standard shows the method of design for each dimension depending on characteristic on design ship and weather and sea condition. On the other hand, in case of existing fairway, it is possible to decide the size of ship and navigation criteria by opposite analysis.

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Study on Prediction of Solar Insolation and Heating Load (일사량 및 난방부하 예측에 관한 연구)

  • Yoo, Seong Yeon;Kim, Tae Ho;Han, Kyu Hyun;Kim, Myung Ho
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.37 no.12
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    • pp.1105-1112
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    • 2013
  • In this study, a method for predicting heating loads using building characteristic coefficients is proposed for heating system control, and a method for predicting hourly temperature and solar insolation, which mainly affect building heating loads, is also proposed. The temperature and solar insolation are predicted by using a fuzzy theory from forecast information at the meteorological agency, and the building characteristic coefficients for the prediction of heating loads are derived from EnergyPlus. The simulated heating loads of the present study show good agreement with those of EnergyPlus. and the variations of the predicted heating loads using the predicted temperature and solar insolation are similar to those using the actual weather data.

Weather Characteristic and Growth of a Forest Ginseng Cultivation Site (산양삼 재배지의 기상특성 및 생육에 관한 연구)

  • Lee, Dong-Sup
    • Journal of Korean Society of Forest Science
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    • v.99 no.6
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    • pp.863-870
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    • 2010
  • We investigated geographical condition and soil characteristic of ginseng cultivation site. At all sites, crown density adjusted by 80%. and Air and soil temperature were also measured. The geographical condition vary ato all sites. and soil shows similar characteristics with typical forest soil of Korea. The results shows the Air temperature needs to be higher than $15^{\circ}C$ for seed budding at April When soil temperature reach at 8, leaf of foest ginseng starts to bud. A forest ginseng is influenced by forest type, planting type and budding rates. In the case of a seedling planting, an seeding emergence rate is high, but the rate is decreased rapidly after three years On the other hand, direct seeding shows lower seedling emergence rate, but survival rate is higher than seedling-planting.

Moisture Absorption of Granular Fertilizer and Its Distribution Characteristic in a Pneumatic Applicator (입제비료의 흡습과 송풍식 살포기에서의 비산특성)

  • Hong, J.H.;Kim, Y.J.;Rhee, J.Y.;Chung, J.H.;Kim, J.Y.;Kim, J.H.;Kim, T.W.
    • Journal of Biosystems Engineering
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    • v.31 no.5 s.118
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    • pp.389-394
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    • 2006
  • The characteristic of moisture absorption of granular fertilizer was measured at several different opening sizes on the top cover of a hopper in a humid weather. The size of the opening was to represent the degree of looseness of sealing of the top cover of the hopper. The application distribution was characterized by the scattering distance of granular fertilizer with different degree of moisture absorption in a pneumatic granular fertilizer applicator. The moisture absorption rates were 12.92 and 12.26 mg of moisture an hour for one gram of each granular fertilizers of NPK 22-12-12 and 21-17-17, respectively. The moisture absorption increased linearly as the opening size increased. The median value of the scattering distance distribution decreased with time of absorption, however, it decreased very slowly after three hours of absorption.

Urban Climate Impact Assessment Reflecting Urban Planning Scenarios - Connecting Green Network Across the North and South in Seoul - (서울 도시계획 정책을 적용한 기후영향평가 - 남북녹지축 조성사업을 대상으로 -)

  • Kwon, Hyuk-Gi;Yang, Ho-Jin;Yi, Chaeyeon;Kim, Yeon-Hee;Choi, Young-Jean
    • Journal of Environmental Impact Assessment
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    • v.24 no.2
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    • pp.134-153
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    • 2015
  • When making urban planning, it is important to understand climate effect caused by urban structural changes. Seoul city applies UPIS(Urban Plan Information System) which provides information on urban planning scenario. Technology for analyzing climate effect resulted from urban planning needs to developed by linking urban planning scenario provided by UPIS and climate analysis model, CAS(Climate Analysis Seoul). CAS develops for analyzing urban climate conditions to provide realistic information considering local air temperature and wind flows. Quantitative analyses conducted by CAS for the production, transportation, and stagnation of cold air, wind flow and thermal conditions by incorporating GIS analysis on land cover and elevation and meteorological analysis from MetPhoMod(Meteorology and atmospheric Photochemistry Meso-scale model). In order to reflect land cover and elevation of the latest information, CAS used to highly accurate raster data (1m) sourced from LiDAR survey and KOMPSAT-2(KOrea Multi-Purpose SATellite) satellite image(4m). For more realistic representation of land surface characteristic, DSM(Digital Surface Model) and DTM(Digital Terrain Model) data used as an input data for CFD(Computational Fluid Dynamics) model. Eight inflow directions considered to investigate the change of flow pattern, wind speed according to reconstruction and change of thermal environment by connecting green area formation. Also, MetPhoMod in CAS data used to consider realistic weather condition. The result show that wind corridors change due to reconstruction. As a whole surface temperature around target area decreases due to connecting green area formation. CFD model coupled with CAS is possible to evaluate the wind corridor and heat environment before/after reconstruction and connecting green area formation. In This study, analysis of climate impact before and after created the green area, which is part of 'Connecting green network across the north and south in Seoul' plan, one of the '2020 Seoul master plan'.

Estimation of Design Flood Runoff in Ungaged Forest Watershed to Reduce Flood Damage within the National Park (국립공원내 홍수피해 저감을 위한 미계측 산림지역의 설계홍수량 추정)

  • Kim, Sang-Min;Im, Sang-Jun;Lee, Sang-Ho;Kim, Hyung-Ho;Ma, Ho-Seop;Jeong, Won-Ok
    • Journal of The Korean Society of Agricultural Engineers
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    • v.51 no.5
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    • pp.107-113
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    • 2009
  • The purpose of this study is to estimate the design flood runoff for ungaged forest watershed to reduce the flood damage in national park. Daewonsa watershed in Jirisan National Park was selected as study watershed, of which characteristic factors were obtained from GIS data. Flood runoff was simulated using SCS unit hydrograph module in HEC-HMS model. SCS Curve Number (CN) was calculated from forest type area weighted average method. Huff's time distribution of second-quartile storm of the Sancheong weather station, which is nearest from study watershed, was used for design flood runoff estimation. Critical storm duration for the study watershed was 3 hrs. Based on the critical duration, the peak runoff for each sub-watershed were simulated. It is recommended to monitor the long-term flow data for major stream stations in National Park for a better reliable peak runoff simulation results.

On the Seasonal Variation of Urban Heat Island Intensity According to Meteorological Condition in Daegu (대구지역의 기상조건에 따른 도시열섬강도의 계절별 변화특성)

  • Ahn Ji-Suk;Kim Hae-Dong
    • Journal of Environmental Science International
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    • v.15 no.6
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    • pp.527-532
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    • 2006
  • The purpose of this study is to clarify the characteristic of urban heat island intensity in urban area formed at a basin. Thermal environments for basin-type cities are influenced by significant topographic relief winds. In this study, we analyzed the diurnal variations of the heat island intensity according to meteorological condition and season using AWS(Automatic Weather observation System) data in Daegu Metropolitan area for 1 year(3/April, 2003 $\sim$ 2/April, 2004). In this study, we defined the urban heat island intensity as the air temperature difference between two points, the downtown and the suburban area. The suburban area is located at valley mouth around the western tip of Daegu. The results are summarized as follows; 1. The maximum heat island intensity was recorded at early morning under the meteorological conditions, calm and clear 2. The heat island intensity was strong in the order of winter, fall, spring and summer. 3. The heat island intensity came out minus values in the afternoon. This phenomenon is known as a com mon for basin-type cities. 4. The heat island intensity was twice or more in clear and calm than not so.

A Study on Course Stability of Towed Damaged-ship under Wind Pressure (풍압력하에서 피예항중인 손상선박의 침로안정성에 관한 연구)

  • K.H. Sohn;Y.K. Kim;S.G. Lee;K.S. Choi
    • Journal of the Society of Naval Architects of Korea
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    • v.37 no.2
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    • pp.46-56
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    • 2000
  • This paper is related with one of safety plans to rescue a damaged-ship whether by collision, grounding or internal accident. We discuss the problem on course stability of damaged-ship while towed under severe wind pressure. The characteristic equation to assess the stability on course, is derived from sway and yaw coupled motion of towing and towed vessels with wind effect. Through the numerical calculation on course stability of towing and towed vessels system, the relationship between the course stability of a towed damaged-ship and wind direction or towrope length, is clarified with the parameters of weather and damage conditions.

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Temperature Control of BIPV system considering out air temperature (외기온도를 고려한 BIPV 시스템의 온도제어)

  • Baek, Jeong-Woo;Ko, Jae-Sun;Choi, Jung-Sik;Kang, Sung-Jun;Jang, Mi-Geum;Kim, Soon-Young;Chung, Dong-Hwa
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2009.10a
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    • pp.371-374
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    • 2009
  • This paper presents a cooling system using thermoelectron for improving the output of BIPV module. The temperature characteristic in regard to improving the output of BIPV system has rarely been studied up to now but some researchers only presented the method using a ventilator. The cooling system efficiency of BIPV module applied to a ventilator mainly depends on the weather such as wind, insolation etc. Because the cooling system of BIPV module using a ventilator is so sensitive, that is being set off by wind speed at all time but is unable to operate in the NOCT(Nominal Operating Cell Temperature) which is able to make the maximum output The paper presents the cooling system using thermoelectron so as to solve such problems. The temperature control of thermoelectron can be controlled independently in the outside environment because that is performed by micro-controller. The temperature control of thermoelectron, also, can be operated around NOCT through algorism of the temperature control. Therefore, outputs of the whole system increase and the efficiency rises. The paper demonstrates the validity of proposed method by comparing the data obtained through a experiment of the cooling method of BIPV using a ventilator and proposed thermoelectron.

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A Study on Application of New & Renewable Energy for Environmental-friendly Planning of Rural Villages - Analysis of Solar Energy Resources - (친환경 농촌마을계획을 위한 재생에너지 활용방안 연구 - 태양에너지 자원분석 -)

  • Nam, Sang-Woon;Kim, Dae-Sik
    • Journal of The Korean Society of Agricultural Engineers
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    • v.50 no.3
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    • pp.105-112
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    • 2008
  • Solar energy, which is one of renewable energy, would be the most useful resources that can be applied to making energy recycling villages without using fossil energy. This study analyzed energy potential on solar energy considering weather condition in three traditional villages and compared with energy consumption surveyed. A photovoltaic system having 3.0kWp capacity of unit module can generate 182.5%, 96.1% and 170.9% of the yearly mean consumption of electric power in Makhyun, Boojang, and Soso, respectively. A flat-plate solar collector having $2.64m^2$ area of unit module can generate warm water of $142{\ell}$/day, $89{\ell}$/day, and $173{\ell}$/day, respectively in three study villages. In Makhyun and Soso, photovoltaic power and warm water produced by solar energy were sufficient to supply required amount of electric power and warm water. However, both electric power and warm water produced by unit solar module were not sufficient in Boojang area, and so it is required to increase the module area by more than 50%. According to the results of this study, the appropriate combination of energy resources can be applied to rural green-village planning if the characteristic of energy potential for each local area is considered.