• 한국환경과학회지
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• 제24권6호
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• pp.807-817
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• 2015

In this study the urban atmospheric environment map in Busan was made and it consist of the atmospheric environment element map and the atmospheric environment analysis map. The atmospheric environment element map covered the topography, the urban climate, the air pollutant emission, ozone and PM10 concentrations in Busan and the atmospheric environment analysis map included the thermal environment and the wind flow by using WRF meteorological numerical simulation. The meteorological elements from 2007 to 2011 in Busan were used in this study. As a result, in the center of Busan and Buk-gu along to the Nakdong river was the temperature high. To analyze the air flow of Busan 3 clusters depending on the wind direction were extracted with the cluster analysis. The results of the analysis on the detailed wind field of each cluster showed that the weak ventilation could be happened locally at the specific meteorological condition.

• Wind and Structures
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• 제9권1호
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• pp.23-35
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• 2006

The effect of buildings on flow in urban canopy is one of the most important problems in local/micro-scale meteorology. A large eddy simulation model is used to simulate the flow structure in an urban neighborhood and the bulk effect of the buildings on surrounding flows is analyzed. The results demonstrate that: (a) The inflow conditions affect the detailed flow characteristics much in the building group, including: the distortion or disappearance of the wake vortexes, the change of funneling effect area and the change of location, size of the static-wind area. (b) The bulk effect of the buildings leads to a loss of wind speed in the low layer where height is less than four times of the average building height, and this loss effect changes little when the inflow direction changes. (c) In the bulk effect to environmental fields, the change of inflow direction affects the vertical distribution of turbulence greatly. The peak value of the turbulence energy appears at the height of the average building height. The attribution of fluctuations of different components to turbulence changes greatly at different height levels, in the low levels the horizontal speed fluctuation attribute mostly, while the vertical speed fluctuation does in high levels.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.1001-1002
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• 2011

Recently, issues regarding environment and the diversification of dependence in oil are watched with keen interest. Wind power attracts most interest because of its high-energy efficiency with eco friendly functions. In this paper, deal with design of radial field permanent magnet synchronous generator for a urban wind power system. Analyzed the RFPM generator by electromagnetic, and designed wind power generator with this. The output characteristic of machine and all of process is analyzed by 2D FEA due to geometrical structures of RFPM machine.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.830_831
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• 2009

Wind power system attracts most interest because of high-energy efficiency with environment-friendly. Small scale wind power applications requires a cost effective and mechanically simple generator in order to be a reliable energy source. The use of direct driven generators, instead of geared machines, reduces the number of drive components, which offers the opportunity to reduce costs and increases system reliability and efficiency. This paper presents the development of a coreless axial-flux permanent magnet(AFPM) generator for a urban wind power system. It is analyzed by electromagnetic simulation program Maxwell 3D

• Structural Monitoring and Maintenance
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• 제4권1호
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• pp.53-68
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• 2017

The response sensitivity method in time domain has been applied extensively for damage identification. In this paper, the relationship between the error of damage identification and the sensitivity matrix is investigated through perturbation analysis. An index is defined according to the perturbation amplify effect and an optimal sensor placement method is proposed based on the minimization of that index. A sequential sub-optimal algorithm is presented which results in consistently good location selection. Numerical simulations with a two-dimensional high truss structure are conducted to validate the proposed method. Results reveal that the damage identification using the optimal sensor placement determined by the proposed method can identify multiple damages of the structure more accurately.

• Wind and Structures
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• 제29권2호
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• pp.99-110
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• 2019

This paper provides a simple numerical method to determine the optimal parameters of tuned mass damper (TMD) and viscoelastic dampers (VEDs) in frame structure for wind vibration control considering the soil-structure interation (SSI) effect in frequency domain. Firstly, the numerical model of frame structure equipped with TMD and VEDs considering SSI effect is established in frequency domain. Then, the genetic algorithm (GA) is applied to obtain the optimal parameters of VEDs and TMD. The optimization process is demonstrated by a 20-storey frame structure supported by pile group for different soil conditions. Two wind resistant systems are considered in the analysis, the Structure-TMD system and the Structure-TMD-VEDs system. The example proves that this method can quickly determine the optimal parameters of energy dissipation devices compared with the traditional finite element method, thus is practically valuable.

• 한국환경생태학회지
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• 제38권1호
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• pp.108-120
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• 2024

본 연구는 변화하는 도시 및 환경 문제, 기후변화 문제에 대응하기 위한 방법 중 하나인 바람길숲 조성과 관련하여 바람길숲의 실효성을 높이기 위한 제도화 방안 및 부처별 연계 방안을 제안하였다. 이를 위해 바람길 관련 용어를 포함하고 있는 법·제도를 검토하여 관련 계획 내에서 요구되는 바람길의 역할 및 상호관계를 파악하였으며, 바람길숲 관련 상위계획 및 바람길숲 기본계획에 대한 검토를 통해 현재 조성되고 있는 바람길숲의 문제점을 파악하여 바람길숲 관련 주요 쟁점을 도출하였다. 이러한 결과를 바탕으로 바람길숲 활성화를 위한 제도화 방안은 크게 바람길숲 법제화를 위한 제도화 방안과 바람길숲의 실효성 있는 활성화를 위한 제도화 방안으로 나누어 법률 정비 및 보완 사항을 제안하였다. 먼저 바람길숲 법제화를 위한 제도화 방안으로는 1)용어의 정립 및 법적·제도적 근거 마련, 2)관련 계획과의 위계정립 및 바람길숲 기본계획의 법적 근거 마련 방안을 제시하였으며, 바람길숲의 실효성 있는 활성화를 위한 제도화 방안으로는 1)지도화 된 공간자료 구축에 대한 법·제도적 근거 마련 방안, 2)바람길숲 기본계획 수립지침 및 바림길숲 조성·관리 가이드라인 마련의 필요성과 그 내용적 범위 등에 대해 제안하였다. 본 연구자료는 바람길숲 관련 법·제도 마련을 위한 기초자료로 활용될 수 있을 것으로 기대되며, 바람길숲 기본계획의 제도화 연구에 활용될 수 있을 것으로 판단된다. 또한 체계적인 바람길숲 조성과 관련하여 기초자료로 활용될 수 있기를 기대한다.

• 한국공간구조학회논문집
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• 제18권2호
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• pp.59-67
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• 2018

Various pilotis are installed in the lower part of high rise buildings. Strong winds can generate sudden airflow around the pilotis, which can cause unexpected internal airflow changes and may cause damage to the exterior of the piloti ceiling. The present study investigates the characteristics of peak wind pressure coefficient for the design of piloti ceiling exteriors by conducting wind pressure tests on high rise buildings equipped with penetration-type and end-type pilotis in urban and suburban areas. The minimum peak wind pressure coefficient for penetration-type piloti ceilings ranges from -2.0 to -3.3. Minimum peak wind pressure coefficient in urban areas was 30% larger than in suburban areas. In end-type piloti ceilings, maximum peak wind-pressure coefficient ranges from 0.5 to 1.9, and minimum peak wind-pressure coefficient ranges from -1.3 to -3.6. With changes in building height, peak wind pressure coefficient decreases as the aspect ratio increases. Peak wind-pressure coefficient increases with taller pilotis. On the other hand, when piloti height decreases, the absolute value of the minimum peak wind pressure coefficient increases.

• Wind and Structures
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• 제3권4호
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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.

• 국제초고층학회논문집
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• 제12권4호
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• pp.287-297
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• 2023

This paper briefly discusses current issues in wind engineering, including the enhancement of aerodynamic database and AI-assisted design, aerodynamic characteristics of tall buildings with atypical building shapes, application of computation fluid dynamics to wind engineering, evaluation of aerodynamic force coefficients based on a probabilistic method, estimation of tornadic wind speed (JEF scale) and effect of the Ekman Spiral on tall buildings.