• Journal of the Korean Institute of Landscape Architecture
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• v.31 no.3
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• pp.58-73
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• 2003

It is well known that urban environment affects climate, as we can see in the quality of bio-climate. However, climate has not been recognised properly in the urban planning process. The role it flays needs to be examined for better urban environment. The main objective of this study is to investigate the climate-ecological priority area which produces cold fresh air and thermal induced wind circulation between rural and urban areas. The objective is also to improve the quality of bio-climate and wind circulation at blocked urban areas. This paper uses the measurement and analysis method of wind direction and wind speed in order to investigate the climate-ecological priority area and cold fresh air corridor. In this study, local climate conditions i.e. wind speed, wind direction, temperature, humidity etc., were measured at nine fields and analyzed. On the basis of the climate measurement, the climate ecological priority areas were delineated; These will be assigned as climate-ecological conservation areas.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.1
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• pp.28-33
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• 2004

The measurement of wind speed gradient is very important for the detection of hazardous wind shear conditions since they are characterized by the abrupt shift of wind velocity and direction. These weather conditions usually imply high wind speed which requires a high PRF radar for the measurement. However, the measurement of a large absolute wind velocity is not necessary to obtain wind speed gradient. In this paper, a method was proposed to obtain wind speed gradient with a simple low PRF radar which may be very useful for the purpose of practical applications.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.05a
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• pp.672-675
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• 2001

In this paper, we propose that the calculation method for accurate wind speed using interpolation methods, and the finding method for accurate wind direction using interpolation polynomial, so we make better performance for 3-Cup Anemometer by the proposed methods. We embody the 3-Cup Anemometer with photo sensor to measure wind direction and wind speed. In order to more accurate wind speed and wind direction, we present the methods to overcome the limitations of system memory and of the sensor measurement error by 8 bit gray code (as substitute 360 degrees for 256 degrees data).

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.05a
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• pp.827-830
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• 2011

In this paper, a wind speed & direction module and the DSP(Digital Signal Processor) sensor interface circuit board are proposed. This DSP system accepts and process the informations from a wind speed & direction module, the atmospheric pressure sensor, the ambient air temperature sensor and transfers it to the PC monitering system. Especially, a wind speed & direction module and a DSP hardware are directly designed and applied. A wind speed & direction module have a construction that it have four film type RTD(Resistive Temperature Detectors) or film type Piezo sensors adhered around the circular metal body for obtaining vector informations about wind. By this structure, the module is enabled precise measurement having a robustness about vibration, humidity, corrosion. A sensor signal processing circuit is using TMS320F2812 TI(Texas Instrument) Corporation high speed DSP.

• Wind and Structures
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• v.18 no.3
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• pp.295-320
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• 2014

The characteristics of amplitudes and power spectra of X axial, Y axial, and RZ axial (i.e., body axis) wind forces on a 492 m high-rise building with a section varying along height in typical wind directions are studied via a rigid model wind tunnel test of pressure measurement. Then the corresponding mathematical expressions of power spectra of X axial (across-wind), Y axial (along-wind) and torsional wind forces in $315^{\circ}$ wind directions are proposed. The investigation shows that the mathematical expressions of wind force spectra of the main structure in across-wind and torsional directions can be constructed by the superimposition of an modified wind spectrum function and a peak function caused by turbulent flow and vortex shedding, respectively. While that in along-wind direction can only be constructed by the former and is similar to wind spectrum. Moreover, the fitted parameters of the wind load spectra of each measurement level of altitude are summarized, and the unified parametric results are obtained. The comparisons of the first three order generalized force spectra show that the proposed mathematical expressions accord with the experimental results well.

• Journal of Industrial Technology
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• v.22 no.A
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• pp.67-72
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• 2002

A technique for alignment to true north is presented, based on synchronized measurements of vision image by a camera and output voltage of wind direction sensor. The true wind direction is evaluated by means of image processing techniques with least square sense, and then evaluated true value is compared with measured output voltage of the sensor. The proposed technique is applied to real meteorological tower m Daekwanryung test site. In addition, some uncertainty analysis of this method is presented.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.499-500
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• 2006

The salt contamination on the distribution facilities was investigated with the wind direction and velocity. Most previous researches were concentrated on the measurement of The Equivalent Salt Deposit Density(ESDD) without environmental consideration. The wind direction and velocity of the many environmental conditions are the most important factors to analyze salt contamination. Pohang area which is located on the south and east of the Korean Peninsula was chosen to do this research. This research will present the result of ESDD depending on the wind direction and velocity.

• Wind and Structures
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• v.21 no.2
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• pp.119-158
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• 2015

The characteristics of the coherence functions of X axial, Y axial, and RZ axial (i.e., body axis) wind forces on the Shanghai World Trade Centre - a 492 m super-tall building with section varying along height are studied via a synchronous multi-pressure measurement of the rigid model in wind tunnel simulating of the turbulent, and the corresponding mathematical expressions are proposed there from. The investigations show that the mathematical expressions of coherence functions in across-wind and torsional-wind directions can be constructed by superimposition of a modified exponential decay function and a peak function caused by turbulent flow and vortex shedding respectively, while that in along-wind direction need only be constructed by the former, similar to that of wind speed. Moreover, an inductive analysis method is proposed to summarize the fitted parameters of the wind force coherence functions of every two measurement levels of altitudes. The comparisons of the first three order generalized force spectra show that the proposed mathematical expressions accord with the experimental results well. Later, the influences of coherence functions on wind-induced dynamic responses are analyzed in detail based on the proposed mathematical expressions and the frequency-domain method of random vibration theory.

• Wind and Structures
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• v.14 no.3
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• pp.253-283
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• 2011

This paper presents the field measurement results of wind effects on a super-tall building (CITIC Plaza, 391 m high) located in Guangzhou. The field data such as wind speed, wind direction and acceleration responses were simultaneously and continuously recorded from the tall building by a wind and vibration monitoring system during two typhoons. The typhoon-generated wind characteristics including turbulence intensity, gust factor, peak factor, turbulence integral length scale and power spectral density of fluctuating wind speed were presented and discussed. The dynamic characteristics of the tall building were determined based on the field measurements and compared with those calculated from a 3D finite element model of the building. The measured natural frequencies of the two fundamental sway modes of the building were found to be larger than those calculated. The damping ratios of the building were evaluated by the random decrement technique, which demonstrated amplitude-dependent characteristics. The field measured acceleration responses were compared with wind tunnel test results, which were found to be consistent with the model test data. Finally, the serviceability performance of the super-tall building was assessed based on the field measurement results.

• Wind and Structures
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• v.35 no.4
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• pp.229-242
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• 2022

Wind tunnel test is often adopted to assess the site-specific wind characteristics for the design of bridges as suggested by current design standards. To investigate the wind characteristics of flat and mountainous terrain, two topographic models are tested in a boundary layer wind tunnel. The wind characteristics, including the vertical and horizontal mean wind speed distributions, the turbulence intensity, and the wind power spectra, are presented. They are investigated intensively in present study with the discussions on the effect of wind direction and the effect of topography. It is indicated that for flat terrain, the wind direction has negligible effect on the wind characteristics, however, the assumption of a homogenous wind field for the mountainous terrain is not applicable. Further, the non-homogeneous wind field can be defined based on a proposed approach if the wind tunnel test or on-site measurement is performed. The calculated turbulence intensities and wind power spectra by using the measured wind speeds are also given. It is shown that for the mountainous terrain, engineers should take into account the variability of the wind characteristics for design considerations.