• 한국대기환경학회지
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• 제34권3호
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• pp.457-468
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• 2018

To improve understanding of the physico-chemical characteristics of aerosols in the national park and comparing the air pollution between national park and the urban area nearby national park, the aerosol characterization study was conducted in Bukhansan National Park, Seoul, from July through September 2017. Semi-continuous measurements of $PM_{2.5}$ using PILS (Particle Into Liquid System) coupled with IC (Ion Chromatography) and TOC (Total Organic Carbon) analyzer allowed quantification of concentrations of major ionic species($Cl^-$, $SO_4{^{2-}}$, $NO_3{^-}$, $Na^+$, $NH_4{^+}$, $K^+$, $Mg{^{2+}}$ and $Ca{^{2+}}$) and water soluble organic carbon (WSOC) with 30-minute time resolution. The total mass concentration of $PM_{2.5}$ was measured by T640 (Teledyne) with 5-minute time resolution. The black carbon (BC) and ozone were measured with a minute time resolution. The timeline of aerosol chemical compositions reveals a strong influence from urban area (Seoul) at the site in Bukhansan National Park. Inorganic aerosol composition was observed to be dominated by ammoniated sulfate at most times with ranging from $0.1{\sim}32.6{\mu}g/m^3$ (6.5~76.1% of total mass of $PM_{2.5}$). The concentration of ammonium nitrate, a potential indicator of the presence of local source, ranged from below detection limits to $20{\mu}g/m^3$ and was observed to be highest during times of maximum local urban (Seoul) impact. The total mass of $PM_{2.5}$ in Bukhansan National Park was observed to be 10~23% lower than the total mass of $PM_{2.5}$ in urban area (Gireum-dong and Bulgwang-dong, Seoul). In general, ozone concentration in Bukhansan National Park was observed to be similar or higher than urban sites in Seoul, suggesting additional biogenic VOCs with $NO_x$ from vehicle emission were to be precursors for ozone formation in Bukhansan National Park.

• 국제초고층학회논문집
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• 제10권2호
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• pp.109-116
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• 2021

This paper explores the meaning and importance of tuning amongst other Tuned Mass Damper (TMD) parameters and describes processes to help ensure that an as-built TMD is properly tuned to the as-built high-rise building. A summary of key TMD components and TMD implementations will be presented as an introduction and review. Next, it will be shown that tuning is a means for optimizing TMD performance. A process using modal characterization tests during tower construction to estimate natural frequencies of the completed tower will be described. Finally, the use of a Frequency Response Function (FRF) as a means for verifying the frequency of a TMD will be proposed.

• Corrosion Science and Technology
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• 제7권2호
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• pp.125-129
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• 2008

Results of corrosion testing for different grades of titanium, copper, zinc, alluminium alloys and steels after two years of outdoor exposure under humid tropical urban and marine conditions have been presented and discussed. Mass loss and corrosion product characteristics for the exposed specimens at Hanoi testing site with high humidity and Nhatrang marine stations (at 100 and 1,000 meters distances from sea) with different airborne salinities (35.9 and $90.0mg/m^2.d$ respectively) have been selected for investigation. From time dependence of the specimen mass loss and corrosion product characteristics, the strong influence of environmental parameters upon durability for the investigated metals and alloys has been demonstrated. Only titanium alloys show high resistance to the marine conditions. All the other specimens (copper, zinc, alluminium alloys and steels) have been underwent strong deterioration under influence of aerosol salinity. Results of corrosion products analysis have been also presented for characterization of environmental impact on the metal degradation processes.

• Environmental Engineering Research
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• 제17권1호
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• pp.47-56
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• 2012

A long-term nationwide nonpoint-source pollution monitoring program was initiated by the Ministry of Environment Republic of Korea (ME) in 2007. Monitoring devices including rain gauges, flow meters, and automatic samplers were installed in monitoring sites to collect dynamic runoff data in 2008-2009. More than 10 rainfall events with three or more antecedent dry days were monitored per year. More than 10 samples were collected and analyzed per event. So far, five land use types (single family, apartments, education facilities, power plants, and other public facilities) have been monitored 23 to 24 times each. Characterization of the runoff from different land use types will aid unit load estimation in Korea and hopefully in other countries with similar land use. The monitoring results will be reported regularly at national and international levels.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.113-119
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• 2003

Building information is extremely important for many applications within the urban environment. Sufficient techniques and user-friendly tools for information extraction from remotely sensed imagery are urgently needed. This paper presents an automatic and manual approach for extracting footprints of buildings in urban areas from airborne Light Detection and Ranging (LIDAR) data. First a digital surface model (DSM) was generated from the LIDAR point data. Then, objects higher than the ground surface are extracted using the generated DSM. Based on general knowledge on the study area and field visits, buildings were separated from other objects. The automatic technique for extracting the building footprints was based on different window sizes and different values of image add backs, while the manual technique was based on image segmentation. A comparison was then made to see how precise the two techniques are in detecting and extracting building footprints. Finally, the results were compared with manually digitized building reference data to conduct an accuracy assessment and the result shows that LIDAR data provide a better shape characterization of each buildings.

• 대한원격탐사학회지
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• 제21권3호
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• pp.243-252
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• 2005

Wavelet transform and its inverse processing provide the effective framework for data fusion. The purpose of this study is to investigate applicability of wavelet transform using texture images for the urban remote sensing application. We tried several experiments regarding image fusion by wavelet transform and texture imaging using high resolution images such as IKONOS and KOMPSAT EOC. As for texture images, we used homogeneity and ASM (Angular Second Moment) images according that these two types of texture images reveal detailed information of complex features of urban environment well. To find out the useful combination scheme for further applications, we performed DWT(Discrete Wavelet Transform) and IDWT(Inverse Discrete Wavelet Transform) using texture images and original images, with adding edge information on the fused images to display texture-wavelet information within edge boundaries. The edge images were obtained by the LoG (Laplacian of Gaussian) processing of original image. As the qualitative result by the visual interpretation of these experiments, the resultant image by each fusion scheme will be utilized to extract unique details of surface characterization on urban features around edge boundaries.

• 대한원격탐사학회지
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• 제22권5호
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• pp.357-366
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• 2006

A traditional image analysis or classification method using satellite imagery is mostly based on the spectral information. However, the spatial information is more important according as the resolution is higher and spatial patterns are more complex. In this study, we attempted to compare and analyze the variogram properties of actual high resolution imageries mainly in the urban area. Through the several experiments, we have understood that the variogram is various according to a sensor type, spatial resolution, a location, a feature type, time, season and so on and shows the information related to a feature size. With simple modeling, we confirmed that the unique variogram types were shown unlike the classical variogram in case of small subsets. Based on the grasped variogram characteristics, we made a level index map for determining urban complexity or land-use classification. These results will become more and more important and be widely applied to the various fields of high-resolution imagery such as KOMPSAT-2 and KOMPSAT-3 which is scheduled to be launched.

• 한국물환경학회지
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• 제22권5호
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• pp.943-951
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• 2006

Spatial distribution of water pollution in the Gap Stream was investigated from October to November, 2005. Sampling was conducted three times including effluents discharged from a wastewater treatment plant (WWTP) and a dam reservoir during the low-flow period. As a typical urban stream, total nitrogen and inorganic nitrogen concentrations increased toward downstream. Ammonia concentration was the highest in the treated water of the wastewater treatment plant and the lowest nitrate concentration was found in the effluent of the dam reservoir. A part of soluble reactive phosphorous (SRP) in total phosphorous was 22~54% in the upstream reach of WWTP in the Gap Stream whereas 68~73% in the downstream reach. Mean chlorophyll-a concentration ranged from 1.6 to $11.0{\mu}g/L$ and it tends to increase toward downstream except for WWTP effluent. As expected, untreated wastewater and WWTP effluent were suggested as the major sources of water pollution in the Gap Stream. In this study, the water pollution of the Gap Stream is a significant undergoing typical eutrophication, caused by excessive phosphorus and nitrogen nutrients from WWTP located in the watershed. As a result, the critical factor for the water pollution was evaluated to dissolved inorganic nitrogen and phosphorus nutrients. Particularly, SRP is a most important for the eutrophication. It suggest that may occur in the most urban streams of Korean peninsula. Therefore, because the necessity of water pollution management in the urban stream, inorganic N and P nutrients should be included as an essential component of water quality criteria in the advanced water quality project of Korean Government by enforcing of water quality assessment and total maximum daily loads (TMDLs).

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2000년도 춘계학술대회 논문집
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• pp.105-107
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• 2000

지금까지 국내외적으로 도심지역의 대기질 평가에 관한 연구로서 알데하이드의 분석은 상당히 많은 관심의 대상이 되어왔다. 광화학스모그의 전조물질로 널리 알려진 알데하이드는 대기중의 탄화수소가 광화학적으로 산화반응을 일으킬 때 형성되고 대기중의 라디칼의 주요 원천이며 유기 에어로졸 형성에도 크게 관여한다 대도시 지역에서는 공장굴뚝에서 방출되는 매연, 자동차의 배기가스가 알데하이드의 주요 인위적인 배출원으로 알려져 있다. (중략)

• 한국전통조경학회지
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• 제34권3호
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• pp.98-114
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• 2016

본 연구는 급변하는 도시 환경에 노출된 도시유산의 경관 보전 및 관리개선을 위한 방안으로 공공재를 활용한 도시유산의 확대와 도시유산과 도시공간과의 연계방안을 제시하고자 함을 목적으로 하였다. 연구결과, 첫째, 도시공간에서 유산의 이해를 높이기 위해 고시도면인 지형도면과 현상변경허용기준, 문화재청 홈페이지의 문화재보존 관리지도를 이용하여 1:1,000지도에 도시유산을 작성하고 주변에 위치한 모든 공공시설을 파악하여 기본도를 작성하였다. 둘째, 도시유산의 현황도 작성을 위해 도시유산과 유산 주변의 현황 및 변화상을 2005년부터 2014년까지 10년간의 사적분과 문화재위원회 회의록을 분석하여 도시유산 주변의 개발행위를 파악하였으며, 도시유산 주변의 보전 가능 지역 및 도시 내 도시유산의 잠재력을 상살 시킬 수 있는 지역을 찾아 활용할 수 있도록 도시유산 주변의 토지이용을 살펴보았다. 또한 현황도 작성 시 도시유산 주변지역의 입지적 특성을 파악하기 위해 단면도를 작성하였으며, 도시유산 주변의 현장 기록화를 위해 유산 및 공공시설의 주요 지점에서 사진촬영을 하였다. 셋째, 도시유산과 유산 주변의 공공시설과의 거리, 위치, 기능, 분포 등의 관계에 의해 도시유산에 미치는 영향 및 잠재적 자원으로서의 기능을 시각적 특징과 동선에 의해 분석하여 도시유산의 전면경관과 유산을 포함한 역사문화경관의 보호방안을 도출하였으며, 또한 공공재의 도시공간에서의 역할 및 도시유산 주변의 활성화 방안을 도출하였다. 넷째, 도시유산 주변의 공공시설 중 도시유산에 직접 또는 간접적인 영향을 주는 공공재를 선정하고, 공공재가 도시유산에 미치는 시각적, 면적, 선적 요소들을 통해 공공재의 역할을 파악하였으며, 이를 통해 도시유산의 경관 및 관리 개선 방안을 제시하였다.