• Journal of the Korean Society of Industry Convergence
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• v.13 no.2
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• pp.55-61
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• 2010

Significant air temperature increases in urban areas are known as the heat island phenomenon in a global scale. Therefore, we use CFD simulation in order to analyze quantitative effects by placing a Building and Green on the heat island phenomenon in urban area. The present study quantitatively analyzes the Urban Heat Island Effects, Outdoor air temperature, and Humidity and air flow.

• New & Renewable Energy
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• v.19 no.3
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• pp.1-12
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• 2023

This study aims to evaluate the optimal size of the hydrogen facility to be installed in a zero-energy district in terms of load matching and facility efficiency. A mismatch between energy generation and consumption is a common occurrence in zero-energy districts. This mismatch adversely effects the energy grid. However, using an energy carrier such as hydrogen can solve this problem. To determine the optimal size of hydrogen fuel cells to be used on-site, simulation of hydrogen installation is required at both district-and building- levels. Each case had four operating schedules. Therefore, we evaluated eight scenarios in terms of load matching, heat loss, and facility operational efficiency. The results indicate that district-level installation of hydrogen facilities enables more efficient energy use. Additionally, based on the proposed model, we can calculate the optimal size of the hydrogen facility.

• Korean Chemical Engineering Research
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• v.47 no.3
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• pp.386-393
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• 2009

This study was to find out the quantitative relation between urban treed area(neighborhood parks) and the atmosphere environment in real condition, focusing the gas-phase non-reacting air pollutants(SOx and NOx) decreasing function of trees in urban area. It also developed a quantitative analysis method for evaluation of the atmosphere influence in the type of treed areas. We set up the Pagoda Park in Seoul and its neighbourhood as a modelling area to analyse air quality impacts by urban neighbourhood park trees. From the modelling result of the Pagoda Park case study, it is concluded that urban neighbourhood park has an important meaning to suppress construction of emission sources which drive the urban polluted air quality worse, even though park's trees have relatively small air purifying function. Especially in the urban area severely contaminated by air pollutants, the first considered air quality management policy is conservation of green spaces in neighborhood park.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.54-55
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• 2015

Increase of impervious areas due to expansion of housing area, commercial and business building of urban is resulting in property change of stormwater runoff. Also, rapid urbanization and heavy rain due to climate change lead to urban flood and debris flow damage. In 2010 and 2011, Seoul had experienced shocking flooding damages by heavy rain. All these have led to increased interest in applying LID and decentralized rainwater management as a means of urban hydrologic cycle restoration and Natural Disaster Prevention such as flooding and so on. Urban development is a cause of expansion of impervious area. It reduces infiltration of rain water and may increase runoff volume from storms. Low Impact Development (LID) methods is to mimic the predevelopment site hydrology by using site design techniques that store, infiltrate, evaporate, detain runoff, and reduction flooding. Use of these techniques helps to reduce off-site runoff and ensure adequate groundwater recharge. The contents of this paper include a hydrologic analysis on a site and an evaluation of flooding reduction effect of LID practice facilities planned on the site. The region of this Case study is LID Rainwater Management Demonstration District in A-new town and P-new town, Korea. LID Practice facilities were designed on the area of rainwater management demonstration district in new town. We performed analysis of reduction effect about flood discharge. SWMM5 has been developed as a model to analyze the hydrologic impacts of LID facilities. For this study, we used weather data for around 38 years from January 1973 to August 2014 collected from the new town City Observatory near the district. Using the weather data, we performed continuous simulation of urban runoff in order to analyze impacts on the Stream from the development of the district and the installation of LID facilities. This is a new approach to stormwater management system which is different from existing end-of-pipe type management system. We suggest that LID should be discussed as a efficient method of urban disasters and climate change control in future land use, sewer and stormwater management planning.

• Proceedings of the KSR Conference
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• 2002.05a
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• pp.603-608
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• 2002

Sound absorbing materials are applied to the exposed surfaces of curved subway tunnel for the reduction of curving noise level. Before the treatment, acoustical engineering simulation is performed to predict the noise level reduction for different kinds and amounts of absorbing material. The principle of geometrical acoustics is utilized to Peform the simulation efficiently and accurately. The noise levels of the inside and outside of running car body are measured to find the noise level reduction. The average noise level reduction of 8 ㏈ has been attained. It has been shown that the simulated results are comparable to the measured ones.

• Wind and Structures
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• v.3 no.4
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• pp.243-253
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• 2000

To develop galloping suppression devices, it is important to understand the effects of wind turbulence on galloping and to establish an evaluation method which takes 'large conductor deformations' into account. This paper introduces some findings on galloping in gusty wind obtained by numerical simulation using a model based on the Mogami Test Line of the Tokyo Electric Power Co. The equations of motion of the conductor are based on the Lagrangian formulations by Simpson, and they are made discrete in accordance with a finite element method.

• Spatial Information Research
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• v.15 no.4
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• pp.397-406
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• 2007

2D hydraulic models of urban areas are at the forefront of current research of flood inundation mechanisms, but they are constrained by inadequate parameters of topography and insufficient data. In this paper a numerical model based on DEMs is presented to represent overflow waters due to bank break in urban areas. The surface flow in the building areas is assumed to be properly modeled by solving Saint-Venant equation. In order to represent flooding broken out in Samcheok city, 2002, hydraulic model test using tracer has been carried out and validated. These efforts will serve for making flood hazard map and for estimating economic loss due to inundation of personal properties in urban areas.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.1
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• pp.57-68
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• 2004

The purpose of this paper is to discover the Image and Visual Preference of the Environmental Sculpture in Urban Streetscape. For this, the analysis was preformed by the data obtained from questionnaires and from the photos of the environmental sculptures scene. The landscape image was analyzed by the factor analysis algorithm. The level of visual preference was measured by a slide simulation test, and this data was analyzed by multiple regression. The results of this study can be summarized as follows: The visual preference of the environmental sculpture has been evaluated to average 4.03 on a scale of 7 Landscape slides No. 11 and No.5 were ranked more highly for visual preference. Factors formulating the landscape image were found to be 'beauty', 'orderliness', 'emotion', and 'formation'. By using the control method for the number of factors, T.V., were obtained as 63.0%. For all experimental landscape slides, the factor of orderliness was found to be the main factor determining the visual preference. The 4 factors for visual preference were analyzed by regression as follows: Visual Preference = 3.996 + 0.341(FS1) + 0.595(FS2) + 0.222(FS3) + 0.011(FS4), R-Square = 0.520.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.12
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• pp.1054-1060
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• 2013

This paper proposes a vehicle ad-hoc network (VANET) routing algorithm to reduce the probability of routing path discontinuity in urban intersections. In urban intersections, the vehicles may frequently change their moving directions. It can cause the disconnection of routing path and the increase of a packet transmission delay. In order to resolve this problem, the proposed routing algorithm exploits the information of moving directions in urban intersections. In this way, the proposed algorithm can reduce the probability of the local maximum which causes the increase of the number of routing hops and packet transmission delay. Simulation results show that the proposed algorithm can reduce the local maximum probability by 10% and increase the successful packet transmission ratio by 5% compared to the conventional VANET routing algorithms.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.11 no.1
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• pp.67-75
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• 1993

The urban expansion and the modernization of the urban infrastructure need a new technology to manage the facilities. The sewer management, one of the urban infrastructures, requires geographical information systems(GIS) for this purpose, and can be supported by the expert system. Consequently, non-professionals can use this system conveniently. In this study, the search and retrieving capacity of the relational database management system(DBMS) and the chain topology generator of the vector-based GIS were integrated into the sewer management system together with the expert knowledge. This system can predict the sewer volume charge by the simulation, and automate these procedures. This system is also user-friendly by using the user-interface. Finally, the system was applied to one of the Seoul drainage districts and tested.