• Title/Summary/Keyword: Coastal city

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Characteristics of Surface Ozone in a Valley Area Located Downwind from Coastal Cities under Sea-breeze Condition: Seasonal Variation and Related Winds (연안 대도시 해풍 풍하측 계곡지역의 지표오존 분포 특성: 계절변화와 바람과의 관계)

  • Kang, Jae-Eun;Oh, In-Bo;Song, Sang-Keun;Kim, Yoo-Keun
    • Journal of Environmental Science International
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    • v.21 no.2
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    • pp.153-163
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    • 2012
  • The seasonal variations of ozone ($O_3$) concentrations were investigated with regard to the relationship between $O_3$ and wind distributions at two different sites (Jung Ang (JA): a semi-closed topography and Seo Chang (SC): a closed topography) within a valley city (Yangsan) and their comparison between these sites (JA and SC) and two non-valley sites (Dae Jeo (DJ) and Sang Nam (SN)) located downwind from coastal cities (Busan and Ulsan). This analysis was performed using the data sets of hourly $O_3$ concentrations, meteorological factors (especially, wind speed and direction), and those on high $O_3$ days exceeding the 8-h standard (60 ppb) during 2008-2009. In summer and fall (especially in June and October), the monthly mean values of the daily maximum $O_3$ concentrations and the number of high $O_3$ days at JA (and SC) were relatively higher than those at DJ (and SN). The increase in daytime $O_3$ concentrations at JA in June was likely to be primarily impacted by the transport of $O_3$ and its precursors from the coastal emission sources in Busan along the dominant southwesterly winds (about 5 m/s) under the penetration of sea breeze condition, compared to other months and sites. Such a phenomenon at SC in October was likely to be mainly caused by the accumulation of $O_3$ and its precursors due to the relatively weak winds under the localized stagnant weather condition rather than the contribution of regional transport from the emission sources in Busan and Ulsan.

Three-Dimensional Laboratory Experiments for Tsunami Inundation in a Coastal City (지진해일 범람이 해안도시에 미치는 영향에 대한 3차원 수리모형실험)

  • Kim, Kyuhan;Park, Hyoungsu;Shin, Sungwon;Cox, Daniel T.
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.24 no.6
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    • pp.400-403
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    • 2012
  • Laboratory experiments were conducted for tsunami inundation to an urban area with large building roughness. The waterfront portion of the city of Seaside which is located on the US Pacific Northwest coast, was replicated in 1/50 scale in the wave basin. Tsunami heights and velocities on the inundated land were measured at approximately 31 locations for one incident tsunami heights with an inundation height of approximately 10 m (prototype) near the shoreline. The inundation pattern and speed were more severe and faster in some areas due to the arrangement of the large buildings. Momentum fluxes along the roads were estimated using measure tsunami inundation heights and horizontal fluid velocities. As expected, the maximum momentum flux was near the shoreline and decreased landward. Inundation heights and momentum flux were slowly decreased through the road with buildings on each side. The results from this study showed that the horizontal inundation velocity is an important factor for the external force of coastal structures.

A Study on how to use drones According to Domestic Coastal Safety System limitations (국내 연안 안전 체계 한계에 따른 드론의 활용방안)

  • Kim, Seung-Han;Kim, Hyo-Joong;Kim, Hyo-Kwan;Cho, So-Hyun
    • Journal of Convergence for Information Technology
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    • v.11 no.1
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    • pp.118-127
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    • 2021
  • In spite of various safety measures, coastal safety accidents continue to occur, so this study focused on using drones as countermeasures. Municipalities that already have coasts have begun operating unmanned multicopters for coastal safety management. In particular, by connecting an unmanned multi-copter to the currently applied smart city safety net system, it is possible to transmit real-time images of the scene in case of emergency in the coastal area to the local government safety information center. It is also expected to contribute significantly to strengthening safety management in coastal waters through a more rapid response to safety accidents. Therefore, in this paper, we propose the use of drones as an alternative to the limitations of the domestic coastal safety system by investigating the state of coastal safety accidents and analyzing the state of domestic coastal safety systems. In addition, it is expected to be a key breakthrough in the coastal area safety system by proposing a model linking the Korean K-Drone system.

Culture and Ecology-Oriented City Marketing: A Case Study of Gangneung City (문화.생태를 이용한 도시마케팅 사례 연구)

  • Heo, Chung-Uk
    • Korean Business Review
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    • v.22 no.2
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    • pp.157-179
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    • 2009
  • This papers aims to focus on the city marketing as the green growth policy strategies using a case study of Gangneung City, Republic of Korea. In the case study it was verified the fields of urban growth including ecology, culture, alternative and recycled energy, green transportation system. The implications of the study were as follows: First, the city government had regenerated the coastal pine forest through removing unlicensed buildings which were squatted down in decades. Secondly, the city government has recognized the value of culture that possessed various types of cultural asserts. Thirdly, it is possible to use and produce the ocean energy with the tidal power plant, wind power plant and green deep water because Gangneung City has the ocean-oriented image and is located the coastal region. Lastly, the city government has been utilizing the LED traffic light using solar heat and is going to apply the green car like an electric car. This paper indicates the importance of the alternatives of the green growth-oriented policy through city marketing using the concept of culture and ecology. The city government will strive after an advanced triple bottom line with the ecological sustainability, cultural diversity and economic effectiveness in the near future.

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Chemical Composition of Fine Particulate Matter in the Downtown Area of Jeju City (제주시 도심지역 미세먼지의 화학적 조성 특성)

  • Hu, Chul-Goo;Lee, Ki-Ho
    • Journal of Environmental Science International
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    • v.27 no.7
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    • pp.597-610
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    • 2018
  • This study observed particulate matter ($PM_{2.5}$ and $PM_{10}$) in the downtown area of Jeju City, South Korea, to understand the chemical composition of particulates based on an analysis of the water-soluble ionic species contained in the particles. The mass fraction of the ionic species in the sampled $PM_{10}$ and $PM_{2.5}$ was 44.3% and 42.2%, respectively. In contrast, in Daegu City and Suwon City, the mass fraction of the ionic species in $PM_{2.5}$ was higher than that in $PM_{10}$. The chloride depletion percentage of $PM_{10}$ and $PM_{2.5}$ in Jeju City was higher than 61% and 66%, respectively. The contribution of sea-salt to the mass of $PM_{10}$ (5.9%) and $PM_{2.5}$ (2.6%) in Jeju City was similar to that in several coastal regions of South Korea. The mass ratio of $Cl^-$ to $Na^+$ in the downtown area of Jeju City was comparable to that in some coastal regions, such as the Gosan Area of Jeju Island, Deokjeok Island, and Taean City. The mass fraction of sea-salt in $PM_{10}$ and $PM_{2.5}$ was very low, and the concentration of sodium and chloride ions in $PM_{10}$ was not correlated with those in $PM_{2.5}$ ($R^2$ < 0.2), suggesting that the effects of sea-salt on the formation of particulate matter in Jeju City might be insignificant. The relationship between $NH_4{^+}$ and several anions such as $SO_4{^{2-}}$, $NO_3{^-}$, and $Cl^-$, as well as the relationship between the measurement and calculation of ammonium ion concentration, suggested that sea-salts may not react with $H_2SO_4$, and $(NH_4)_2SO_4$ may be a major secondary inorganic aerosol component of $PM_{2.5}$ and $PM_{10}$ in Jeju City.

A Study on Non-point Source Pollutants from Pavement of Coastal Area and Guidance for Selecting BMP (연안지역 포장면 비점오염물질 유출 및 최적관리방안 시설의 선정을 위한 가이던스에 관한 연구)

  • Ko, Woong;Park, Kisoo;Chen, Yaoping;Kim, Youngchul
    • Journal of Wetlands Research
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    • v.15 no.4
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    • pp.543-553
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    • 2013
  • In Korea, there have been many studies and progresses on various types of pilot scale or commercialized field scale Best Management Practices(BMP) during the last 10 years. Runoff characteristics of diffuse pollutants from different land uses are well identified and documented. However, for the coastal area connected directly with shoreline, runoff patterns and management schemes of non-point pollution were not fully studied. Recently, coastal area is emerging as a new development axis especially in west coast side of Korea such as Incheon city and Chungnam province, thus urbanized area rapidly increased but there are no buffer zones and BMP facilities to aim at preventing direct discharge of the first flush into coastal sea and beaches. In this study, parking area in Deacheon harbor, Boryeong City in Chungnam Province was selected and rainfall runoff was monitored for two year period in order to examine run-off features from which proper type of BMP suitable for coastal area is proposed. Coastal area usually has a low ground water level and consists of plain land, so that large scale BMP such as storm water retention pond and wetland requiring great excavation works is not best management plan. In addition, monitoring study shows that storm water from the paved parking area has a high salinity compared with those in storm water from the inland. High salinity is detrimental for the vegetation. Therefore, BMP employing least vegetative cover and also in terms of maintenance is a good option such as infiltration trench and porous pavement.

Sensitivity Analysis in the Prediction of Coastal Erosion due to Storm Events: case study-Ilsan beach (태풍 기인 연안침식 예측의 불확실성 분석: 사례연구-일산해변)

  • Son, Donghwi;Yoo, Jeseon;Shin, Hyunhwa
    • Journal of Coastal Disaster Prevention
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    • v.6 no.3
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    • pp.111-120
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    • 2019
  • In coastal morphological modelling, there are a number of input factors: wave height, water depth, sand particle size, bed friction coefficients, coastal structures and so forth. Measurements or estimates of these input data may include uncertainties due to errors by the measurement or hind-casting methods. Therefore, it is necessary to consider the uncertainty of each input data and the range of the uncertainty during the evaluation of numerical results. In this study, three uncertainty factors are considered with regard to the prediction of coastal erosion in Ilsan beach located in Ilsan-dong, Ulsan metropolitan city. Those are wave diffraction effect of XBeach model, wave input scenario and the specification of the coastal structure. For this purpose, the values of mean wave direction, significant wave height and the height of the submerged breakwater were adjusted respectively and the followed numerical results of morphological changes are analyzed. There were erosion dominant patterns as the wave direction is perpendicular to Ilsan beach, the higher significant wave height, and the lower height of the submerged breakwater. Furthermore, the rate of uncertainty impacts among mean wave direction, significant wave height and the height of the submerged breakwater are compared. In the study area, the uncertainty influence by the wave input scenario was the largest, followed by the height of the submerged breakwater and the mean wave direction.

3-D Numerical Prediction Modeling of Air Pollution in Coastal Urban Region -(I) An Effect Prediction for Deposition Phenomenon affecting on Air Quality (연안도시지역에서 대기오염의 3차원 수치예측모델링 -(I) 침적현상이 대기질에 미치는 영향예측)

  • 원경미;이화운
    • Journal of Korean Society for Atmospheric Environment
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    • v.15 no.5
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    • pp.625-638
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    • 1999
  • Air quality modeling for coastal urban region has been composed of a complex system including meteorological, chemical and physical processes and emission characteristics in complex terrain. In this study, we studied about an effect prediction for deposition phenomenon affecting on air quality in Pusan metopolitan metropolitan city. In air quality modeling including ship sources, a situation considered deposition process habe better result than not considered when compared with observed value. Air pollutants emitted into urban air during the daytime nearly removed through urban atmosphere polluted. Also these phenomena correlated concentration variation connent with sea/land breezes and terrain effect. Therefore we conclude that the concentration was low at daytime when deposition flux is high, and deposition effect on industrial complex and Dongrae region is considerable in particular.

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Automatic Generation of a SPOT DEM: Towards Coastal Disaster Monitoring

  • Kim, Seung-Bum;Kang, Suk-Kuh
    • Korean Journal of Remote Sensing
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    • v.17 no.2
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    • pp.121-129
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    • 2001
  • A DEM(digital elevation model) is generated from a SPOT panchromatic stereo-pair using automated algorithms over a 8 km$\times$10 km region around Mokpo city. The aims are to continue the accuracy assessment over diverse conditions and to examine the applicability of a SPOT DEM for coastal disaster monitoring. The accuracy is assessed with respect to three reference data sets: 10 global positioning system records, 19 leveling data, and 1:50,000 topography map. The planimetric error is 10.6m r.m.s. and the elevation erroer ranges from 12.4m to 14.4m r.m.s.. The DEM accuracy of the flat Mokpo region is consistent with that over a mountainous area, which supports the robustness of the algorithms. It was found that coordinate transformation errors are significant at a few meters when using the data from leveling and topographic maps. The error budget is greater than the requirements for coastal disaster monitoring. Exploiting that a sub-scene is used, the affine transformation improves the accuracy by 50% during the camera modeling.