• Journal of Applied Reliability
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• v.12 no.2
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• pp.91-103
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• 2012

Tubular markers for road safety facilities are used to lead the driver's sight line and separate the lanes on the road. Such tubular markers are usually installed on the road and frequently hit by vehicles, they are accordingly requested to assure the product durability. The traditional evaluation method of tubular markers include only quality tests of the material properties. However, most of consuming agencies in charge of road management at fields have proposed problems on long-term performance of the products hit by vehicles under various weather conditions. Therefore, the objectives of this study are to develop the reliability test methods and equipments to simulate the product failures of tubular markers due to vehicle collision and wheel compression and the delamination and discoloration of reflection sheets attached on the surface of the products under high and low temperatures.

• Journal of environmental and Sanitary engineering
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• v.20 no.4 s.58
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• pp.1-8
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• 2005

Pocheon is a basin geographically, and the diffusion of air pollutants is very difficult. Thus, it is essential to consider the characteristics of geographical and weather conditions before industrial complex and various air pollution sources are developed in the area. It is recommended that Environmental Impact Statements (EIS) must be carried out before any action is taken. Constantly occurring fog in the Pocheon area absorbs large amounts of acidic gases, and it transformed into the secondary pollutants such as the salts of sulfate and nitrate. Fog, which occurs very often in Pocheon area, was analyzed for its acid components. Conversion from the gaseous sulfur dioxide into sulfate ion is relatively high, $86\~90\%$ while $68\~76\%$ of NOx is converted into nitrate ion form.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.590-593
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• 2009

Tidal current power system is one of ocean renewable energies that can minimize the environmental impact with many advantages compared to other energy sources. Not like others, the produced energy can be precisely predicted without weather conditions and also the operation rate is very high. To convert the current into power, the first device encountered to the incoming flow is the rotor that can transform into rotational energy. The performance of rotor can be determined by various design parameters including numbers of blade, sectional shape, diameter, and etc. The stream lines near the rotating rotor is very complex and the interference effects around the system is also difficult to predict. This paper introduces the experiment of rotor performance and also the effect of design parameter on the performance of HAT rotor by CFD.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.1
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• pp.58.4-59
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• 2021

This presentation introduces Korea's SNIPE (Small scale magNespheric and Ionospheric Plasma Experiment) mission, formation flying CubeSat constellation. Observing particles and waves on a single satellite suffers from inherent space-time ambiguity. To observe spatial and temporal variations of the micro-scale plasma structures on the topside ionosphere, four 6U CubeSats (~ 10 kg) will be launched into a polar orbit of the altitude of ~500 km in 2021. The distances of each satellite will be controlled from 10 km to more than 100 km by formation flying algorithm. The SNIPE mission is equipped with identical scientific instruments, solid-state telescope, magnetometer, and Langmuir probe. All the payloads have a high temporal resolution (sampling rates of about 10 Hz). Iridium modules provide an opportunity to upload changes in operational modes when geomagnetic storms occur. SNIPE's observations of the dimensions, occurrence rates, amplitudes, and spatiotemporal evolution of polar cap patches, field-aligned currents (FAC), radiation belt microbursts, and equatorial and mid-latitude plasma blobs and bubbles will determine their significance to the solar wind-magnetosphere-ionosphere interaction and quantify their impact on space weather.

• Journal of the Korean Society of Costume
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• v.65 no.1
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• pp.15-29
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• 2015

The fashion items of the "Rainy Look" has become fashion items that could be worn in any weather. Accordingly, there is a need for this study to research the fashion items of the Rainy Look as its influence is becoming big enough to impact modern fashion and expand into the high fashion and street fashion. First of all, the purpose of this study is to analyze the fashion items of the Rainy Look that were represented in the high fashion and street fashion of 21st century. And the analysis was performed using the following categories: the functional aspect, aesthetic aspect, and the formativeness of fashion items. Through this, the study provided fashion styling materials using the Rainy Look fashion items. This study examined the concepts and characteristics of the Rainy Look as a literature study and analyzed its characteristics, which appeared in collections and street fashions. Especially as attires coordinated with business casuals in the street fashion, they appeared often among commuting office workers. And the conveniences of having a string in the waistline or securing storage space or detachable function. On the contrary, traditional raincoat designs appeared often in high fashion and as feminine styles, which is characterized by a slimmed waist with a use of a belt. and a flared lower part, such as shoulder patch or strap.

• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.2
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• pp.15-26
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• 2012

For stable and sustainable crop production, understanding the effects of climate changes on agricultural water resources is necessary to minimize the negative effects which might occur due to shifting weather conditions. Although various studies have been carried out in Korea concerning changes in evapotranspiration and irrigation water requirement, the findings are still difficult to utilize fordesigning the demand and unit duty of water, which are the design criteria of irrigation systems. In this study, the impact analysis of climate changes on the paddy water demand and unit duty of water was analyzed based on the high resolution climate change scenarios (specifically under the A1B scenario) provided by the Korea Meteorological Administration. The result of the study indicated that average changes in the paddy water demand in eight irrigation districts were estimated as -2.4 % (2025s), -0.2 % (2055s), and 3.2 % (2085s). The unit duty of water was estimated to increase on an average within 2 % during paddy transplanting season and within 5 % during growing season after transplanting. This result could be utilized for irrigation system design, agricultural water resource development, and rice paddy cultivation policy-making in South Korea.

• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.33-36
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• 2007

We have persistently constructed gridded products of surface wind/wind stress over the world ocean using satellite scatterometer (ERS and Qscat). They are available for users as the Japanese Ocean Flux data sets with Use of Remote sensing Observation (J-OFURO) data together with heat flux components. Recently, a new version data of the Qscat/SeaWinds based on improved algorithm for rain flag and high wind-speed range have been delivered, and allowed us to reconstruct gridded product with higher spatial resolution. These products are validated by comparisons with in-situ measurement data by mooring buoys such as TAO/TRITON, NDBC and the Kuroshio Extension Observation (KEO) buoys, together with numerical weather prediction model products such as the NCEP-1 and 2. Results reveal that the new product has almost the same magnitude in mean difference as the previous version of Qscat product and much smaller than the NCEP-1 and 2. On the other hand, it is slightly larger root-mean-square (RMS) difference than the previous one and NCEPs for the comparison using the KEO buoy data. This may be due to the deficit of high wind speed data in the buoy measurement. The high resolution product, together with sea surface temperature (SST) one, is used to examine a new type of relationship between the lower atmosphere and upper ocean in the Kuroshio Extension region.

• Journal of the Korean earth science society
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• v.36 no.4
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• pp.315-329
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• 2015

We investigated the characteristics of meteorological conditions related to the strong downslope wind over the leeward side of the Taebaek Mountains during the period 2005~2010. The days showing the strong wind exceeding $14ms^{-1}$ in Gangwon province were selected as study cases. A total of 15 days of strong wind were observed at Sokcho, Gangneung, Donghae, and Taebaek located over the Yeongdong region. Seven cases related to tropical cyclone (3 cases) and heavy snowfall (2 cases) and heavy rainfall (2 cases) over the Yeongdong region were excluded. To investigate the characteristics of the remaining 8 cases, we used synoptic weather chart, Sokcho radiosonde, Gangneung wind profiler and numerical model. The cases showed no precipitation (or ${\leq}1mm\;day^{-1}$). From the surface and upper level weather chart, we found the pressure distribution of southern high and northern low pattern over the Korean peninsula and warm ridge over the Yeongdong region. Inversion layer (or stable layer) and warm ridge with strong wind were located in about 1~3 km (925~700 hPa) over mountains. The Regional Data Assimilation and Prediction System (RDAPS) indicated that warm core and temperature ridge with horizontal temperature gradient were $0.10{\sim}0.23^{\circ}C\;km^{-1}$ which were located on 850 hPa pressure level above mountaintop. These results were summarized as a forecasting guidance of downslope windstorm in the Yeongdong region.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.3
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• pp.146-157
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• 2019

One of the most distinctive features of the South Korean rural environment is that the variation of weather or climate is large even within a small area due to complex terrains. The Geospatial Schemes based on Topo-Climatology (GSTP) was developed to simulate such variations effectively. In the present study, we reviewed the progress of the geospatial schemes for production of farm-scale agricultural weather data. Efforts have been made to improve the GSTP since 2000s. The schemes were used to provide climate information based on the current normal year and future climate scenarios at a landscape scale. The digital climate maps for the normal year include the maps of the monthly minimum temperature, maximum temperature, precipitation, and solar radiation in the past 30 years at 30 m or 270 m spatial resolution. Based on these digital climate maps, future climate change scenario maps were also produced at the high spatial resolution. These maps have been used for climate change impact assessment at the field scale by reprocessing them and transforming them into various forms. In the 2010s, the GSTP model was used to produce information for farm-specific weather conditions and weather forecast data on a landscape scale. The microclimate models of which the GSTP model consists have been improved to provide detailed weather condition data based on daily weather observation data in recent development. Using such daily data, the Early warning service for agrometeorological hazard has been developed to provide weather forecasts in real-time by processing a digital forecast and mid-term weather forecast data (KMA) at 30 m spatial resolution. Currently, daily minimum temperature, maximum temperature, precipitation, solar radiation quantity, and the duration of sunshine are forecasted as detailed weather conditions and forecast information. Moreover, based on farm-specific past-current-future weather information, growth information for various crops and agrometeorological disaster forecasts have been produced.

• Journal of Environmental Impact Assessment
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• v.26 no.6
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• pp.470-478
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• 2017

This study was classified into two groups, normal season group and drought season group, by the cluster analysis using the weather and water quality data from 2012 to 2015, using SPSS 18 version. Also each cluster was classified into three spaces, Gangcheon, Yeoju and Ipoh weir. We performed the multiple regression analysis with each monthly data that concentration of Chl-a was more than algae warming level. 6 groups classified in time and space were analyzed by the correlation analysis between concentration of Chl-a and 3 weather, 11 water quality and discharge factors. We developed Chl-a prediction equations of each group with independent variables of the multiple regression analysis applying to the correlation result. The result of cluster analysis was that the period was divided into two groups, normal group(2012-2013) that total annual precipitation rate was normal and drought group(2014-2015) that total annual precipitation rate was less than 1,000 mm/hr, in time. The months that concentration of Chl-a was more than algae warming level in each group classified by cluster analysis were that the normal group was 3~8 and drought group was 3 and 6~10. The correlation result between Chl-a and weather, water quality and discharge factors for each 6 group was that relationships between Chl-a and water, discharge factors were high in the drought group more than in normal group at all weirs. This was influenced by velocity reduction and increasing HRT according to the intense drought. Weather, water quality and discharge factors that were high correlation with Chl-a were applied to independent variables of Chl-a prediction equations and each equations were developed. Among them, Each adjusted R square of Prediction equations for Chl-a in each group at Ipoh weir where is located in Namhan river downstream and is directly connected to Paldang dam were normal group = 0.920 and drought group = 0.818. It's showed the high linear.