• Title/Summary/Keyword: Complex urban area

Search Result 449, Processing Time 0.025 seconds

Enhancement of Vertical Atmospheric Dispersion Due to Roughness (조도에 기인한 연직방향 대기확산의 증대)

  • 박목현
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.14 no.6
    • /
    • pp.643-650
    • /
    • 1998
  • Many atmospheric dispersion models have been based on the Gaussian distribution concept of plume spread. In application of Gaussian plume dispersion models, vertical dispersion coefficient 3 has been known as a sensitive variable. Vertical diffusivity K2 (=Oz2/2t) tends to increase with surface roughness, and the value of K3 in urban area is larger than that in rural area due to heat emission as well as increased roughness. Though Pasquill proposed a modification scheme for qz vs x system of Pasquill-Gifford under consideration of roughness effect in 1976, there appears not to be realistic reexamination on the modification scheme. In this study literature review on the effect of terrain or roughness on venical plume dispersion has been carried out in order to improve the prediction results of atmospheric pollution concentration. Again a few research objectives on vertical atmospheric dispersion in complex terrain were Proposed.

  • PDF

Study on the Discharge Characteristics of Non-point Pollutant Source in the Urban Area of the Youngsan-River Basin (영산강 유역 도시지역의 비점오염원 배출특성에 관한 연구)

  • Jin, Young-Hoon;Park, Sung-Chun
    • Journal of Korean Society on Water Environment
    • /
    • v.22 no.4
    • /
    • pp.605-613
    • /
    • 2006
  • Discharge characteristics of non-point source pollutant and load amount of the discharge in the urban area were investigated in the Pungyeongjeong-stream basin and the Yongbong-stream basin in this present study. The land use of the studied basins were divided into paddy field, industrial complex area, combined sewage system, separate sewer system and point sources discharge. The descriptive statistics on the event mean concentrations (EMCs) of non-point pollutants by the the land use showed in the range of 4.43-32.28 mg/L for BOD and 8.27~56.17 mg/L for COD. The highest concentration was shown from the combined sewage system. The EMC of SS at the paddy field in the Pungyeongjeong-stream basin showed the highest range with the values ~ from 35.76 to 358.86 mg/L, which might have been influenced by a levee construction in the adjacent of the area. The relatively high concentration values of 4.43~32.28 mg/L and 1.617.13 mg/L emerged from TN and TP,respectively, at the discharge points of the both stream basins.

IKONOS Stereo Matching with Land Cover Map for DEM Generation

  • Lee, Hyo-Seong;Ahn, Ki-Weon;Park, Byung-Guk;Han, Dong-Yeob
    • Proceedings of the KSRS Conference
    • /
    • 2007.10a
    • /
    • pp.580-583
    • /
    • 2007
  • Various matching methods have been introduced by investigators to improve digital elevation model (DEM) accuracy of satellite imagery. This study proposed an area-based matching method according to land cover property using correlation coefficient of pixel brightness value between the two images for DEM generation from IKONOS stereo imagery. For this, matching line (where "matching line" implies straight line that is approximated to complex nonlinear epipolar geometry) is established by exterior orientation parameters to minimize search area. The matching is carried out based on this line. Land cover classes are divided off into water, urban land, forest and agricultural land. Matching size is selected using a correlation-coefficient image in the four areas. The selected sizes are $81{\times}81$ pixels window, $21{\times}21$ pixels window, $119{\times}119$ pixels window and $51{\times}51$ pixels window in the water area, urban land, forest land and agricultural land, respectively. And hence, DEM is generated from IKONOS stereo imagery using the selected matching sizes and land cover map on the four types.

  • PDF

DETERMINANTS OF APARTMENT RENTS IN THE SEOUL METROPOLITAN REGION: SPATIAL ECONOMETRIC APPROACHES

  • Lee, Dongsung
    • Journal of Urban Science
    • /
    • v.9 no.1
    • /
    • pp.33-40
    • /
    • 2020
  • This research aims to analyze the determinants of apartment rents in the Seoul Metropolitan area using spatial econometrics approaches. Since spatial econometrics approaches have advantages to solve limitations of ordinary multiple regression such as spatial dependence and spatial heterogeneity. This research includes structural variables such as number of rooms and baths, neighborhood variables such as number of housing units in the apartment complex, and location variables including distances to subway stations, to traditional markets, to educational institutes, and to urban services such as parks, etc. The result shows that the accessibilities to the CBD, to subcenters, to subway station, to school, and to parks contribute to apartment rent uplift and also shows different spatial variations in rent premiums by accessibility variables. In particular, apartments located south of Han river along the Lines 2, 3, 7 and 9 have the highest rent premiums due to the accessibility to the subway.

A Study on the Design Structural Concepts and the Elemental Characteristics for the Utilization of Underground Space (지하공간 활용을 위한 디자인 구성개념 및 요소특성에 관한 연구)

  • 이영수;김민경
    • Korean Institute of Interior Design Journal
    • /
    • no.29
    • /
    • pp.94-102
    • /
    • 2001
  • The urban land is incapacitated to grow and correspond to demand the space in urban area. And recently, rapid increasing of population and complex of urban function on pushed to develop the underground space. In Korea, the underground space development in inefficient in aspect. because development of underground space have not consistent and systematic planning method in underground environment inclounding interion design, extererior design. Therefore this study is suggested the design element for comfortable underground living environment and assortment on utilization of underground space. The results of this study on utilization are security of space through land use efficiency, conservation of historical place, building and natural environment, and technological characteristics, mental image. Accordingly, this study is proposed design element that make comfortable underground space as aspect from stimulation and diversity, sapciousness and feeling of warmth and dryness to compensate improper image of underground space, spacial orientation and way finding.

  • PDF

Application Method of Satellite Image and GIS for Suitability of Black Locust Forest as Honey Plant Area (아까시나무 밀원식물단지 적지 선정을 위한 위성영상과 GIS의 응용기법)

  • Jo, Myung-Hee;Kim, Joon-Bum;Jo, Yun-Won;Baek, Seong-Ryul
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.4 no.2
    • /
    • pp.27-37
    • /
    • 2001
  • Using satellite image and GIS, spatial distribution characteristics of black locust forest as honey plant area was identified and analyzed. Upon the result, the most suitable area for black locust forest was selected through the integration analysis of transparent overlay. The variables used for spatial analysis such as topography(elevation, aspect, slope), soil, drainage, distance from urban area, land use, meteorological elements were considered. Based on the suitability analysis, it was clarified that the integration of linear and factor combination technique is greatly efficient method for the most suitable area. In addition, Gokung, Imgo, Chungtong, Hwanam area were shown to be suitable in Young-chun Area. As the result of suitability analysis for honey plant area of black locust in Young-chun using satellite image and GIS, the present portion of potential distribution area was produced about 42.53%. The portion of most suitable area for honey plant area of black locust was about 26.77%. Finally, the total area for honey plant area of black locust in Young-chun came up to $15.79km^2$. Additionally, satellite image and GIS were expected to be significant tools for suitability analysis of honey plant complex area.

  • PDF

Characteristics Analysis of Water Quality for A Small Stream in Urban Watershed (소규모 도시 하천 유역의 수질 특성 연구)

  • Kwak, Jae Won;Jung, Jong Tae;Kim, Hung Soo;Ahn, Kyoung Soo
    • Journal of Wetlands Research
    • /
    • v.10 no.2
    • /
    • pp.129-141
    • /
    • 2008
  • This study analyzed and assessed the water quality of a small urban stream in the apartment complex of Yewol-Dong, Buchun-Si at Korea. The flows in the stream due to the interceptions of sewage and normal flow are usually low and the water quality and offensive odor problems by inflows of the sewage and other pollutants are occurred in the study area. Therefore we intended to monitor and identify the water quality conditions. Based on this, we simulated water quality using QUAL2E model and investigated water quality characteristics for the future. As the results, we found that the water quality depended on the inflows of point and non-point sources and so it is important to maintain instream flow for improvement of water quality problem and to intercept point and non-point sources in this study area.

  • PDF

Characteristics of Air Quality in the West Coastal Urban Atmosphere; Characteristics of VOCs Concentration Measured from an Industrial Complex Monitoring Station at Gunsan and a Roadside Station at Jeonju (서해연안 도시지역의 대기질 특성 연구: 군산시 산업단지와 전주시 도로변에서 VOCs 농도분포 특성 연구)

  • Ryoo, Jae-Youn;Kim, Deug-Soo;Chae, Soo-Cheon;Nam, Tu-Cheon;Choi, Yang-Seock
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.26 no.6
    • /
    • pp.633-648
    • /
    • 2010
  • The study was performed to elucidate the characteristics of VOCs at distinct monitoring sites in urban atmosphere; one is at a roadside in downtown inland city of Jeonju, and the other is at an industrial site in Gunsan near coastal area. The ambient samples were collected for 24 hours in two-bed adsorbent tubes by using MTS-32 sequential tube sampler equipped with Flex air pump every 16 days in a roadside and a industrial complex from February to November in 2009. VOCs were determined by thermal desorption coupled with GC/MSD. Major individual VOCs in roadside samples were shown as following order in magnitude: toluene>m,p-xylene>ethyl benzene>decanal; and those in the industrial complex samples were as follows: toluene>ethanol>ethyl acetate>decanal>m,pxylene. High benzene concentration in the roadside was more frequently occurred than in the industrial complex. However ambient level of toluene in the industrial complex was higher than that in the road side. Results from roadside sample analysis showed that nonane and 1,2,4-trimethylbenzene were very frequently observed with higher concentrations than those in the industrial complex. It seems that nonane and 1,2,4-trimethylbenzene could be the source characteristics for the roadside air. From the diurnal variation, it was found that concentrations of benzene, ethylbenzene, xylene, nonane and 1,2,4-trimethylbenznene in the roadside were higher during rush hours; but those in the industrial complex were higher from 10 to 16 LST when the industrial activities were animated. On weekly base, the concentration of benzene, toluene, ethylbenzene and m,p-xylene in the roadside were higher specifically on Wednesday, but those in the industrial complex were higher on Sunday. It was found that the general trends of VOCs levels at both sites significantly influence on seasonal changes. The results of factor analysis showed that the VOCs in the roadside were mainly affected by the emission of vehicles and the evaporation of diesel fuel, meanwhile those in the industrial complex were influenced by the evaporation of solvents and vehicular emission.

Analysis of Cold Air Flow Characteristics according to Urban Spatial Types to Construct a Wind Road - Focused on Urban Area of Changwon - (바람길 조성을 위한 도시공간유형별 찬공기 유동 특성 분석 - 창원시 도시지역을 중심으로 -)

  • LEE, Su-Ah;SONG, Bong-Geun;PARK, Kyung-Hun
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.25 no.2
    • /
    • pp.30-47
    • /
    • 2022
  • This study analyzed the characteristics of cold air flow according to spatial types in urban areas of Changwon-si, Gyeongsangnam-do. The spatial types were classified by cluster analysis considering the land use map, building information, and topographic characteristics produced on the Changwon biotope map. The amount of cold air and wind speed were derived by KLAM_21 modeling. As a result, spatial types were classified into a total of 14 types considering the density and height of buildings, land use types, and topographic characteristics. Cold air flow was found to generate cold air in the valley of the forest area outside urban area, move through roads and open spaces, and accumulate in the low-lying national industrial complex, and then spread cold air throughout the urban areas. There was a lot of cold air flow in the tall building area, and the cold air accumulation was less in the slope and ridge areas. The results of this study were able to understand the characteristics of cold air flow according to building density, land use type, and topography, which will be usefully used as basic data for urban wind road construction to mitigate climate and improve air quality in urban areas.

A Study of Applications of DSM in tunnelling to an underground shopping-area (도심지 지하상가 연결통로 DSM(Divided Shield Method)공법 적용사례 연구)

  • Hong, Chang-Soo;Hwang, Dae-Jin;Lee, Kang-Ho;Cho, Keum-Sik
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2005.10a
    • /
    • pp.556-563
    • /
    • 2005
  • Recently, it is used to join an building to an underground shopping-area in urban. When we construct Seo-Cho Complex building which is in Seoul, we also construct an underground passage to the Gangnam underground shopping-area. But it is difficult to excavate in the downtown area, because excavations induce traffic jam and public discontent. Considering safety, a confined area, settlements, we decided to use DSM(Divided Shield Method) which is based on messer shield. This paper will produce our experience and the results provide a useful guide in a connection tunnel

  • PDF