• Title/Summary/Keyword: towers

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Comparison of Land Surface Temperatures from Near-surface Measurement and Satellite-based Product

  • Ryu, Jae-Hyun;Jeong, Hoejeong;Choi, Seonwoong;Lee, Yang-Won;Cho, Jaeil
    • Korean Journal of Remote Sensing
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    • v.35 no.4
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    • pp.609-616
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    • 2019
  • Land surface temperature ($T_s$) is a critical variable for understanding the surface energy exchange between land and atmosphere. Using the data measured from micrometeorological flux towers, three types of $T_s$, obtained using a thermal-infrared radiometer (IRT), a net radiometer, and an equation for sensible heat flux, were compared. The $T_s$ estimated using the net radiometer was highly correlated with the $T_s$ obtained from the IRT. Both values acceptably fit the $T_s$ from the Terra/MODIS (Moderate Resolution Imaging Spectroradiometer)satellite. These results will enhance the measurement of land surface temperatures at various scales. Further, they are useful for understanding land surface energy partitioning to evaluate and develop land surface models and algorithms for satellite remote sensing products associated with surface thermal conditions.

Sensor Network Application : Meteorological Map Service Using Mobile Phone Sensor (센스 네트워크 응용 : 휴대폰 센스를 이용한 기상 지도 서비스)

  • Choi, Jin-oh
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2009.05a
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    • pp.203-206
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    • 2009
  • Because the meteorological observation towers are scattered over large area, the collected meteorological data are very sparse. Therefore, the need for data collection on the limited urban areas like a specific building or subway area brings about vest cost which is required to install the corresponding sensors on the areas. Recently, to overcome this problem, the sensor network technique comes to the fore. This paper studies an application to service the meteorological map using mobile phone sensors.

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Aerodynamic and hydrodynamic force simulation for the dynamics of double-pendulum articulated offshore tower

  • Zaheer, Mohd Moonis;Islam, Nazrul
    • Wind and Structures
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    • v.32 no.4
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    • pp.341-354
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    • 2021
  • Articulated towers are one of the class of compliant offshore structures that freely oscillates with wind and waves, as they are designed to have low natural frequency than ocean waves. The present study deals with the dynamic response of a double-pendulum articulated tower under hydrodynamic and aerodynamic loads. The wind field is simulated by two approaches, namely, single-point and multiple-point. Nonlinearities such as instantaneous tower orientation, variable added mass, fluctuating buoyancy, and geometrical nonlinearities are duly considered in the analysis. Hamilton's principle is used to derive the nonlinear equations of motion (EOM). The EOM is solved in the time domain by using the Wilson-θ method. The maximum, minimum, mean, and standard deviation and salient power spectral density functions (PSDF) of deck displacement, bending moment, and central hinge shear are drawn for high and moderate sea states. The outcome of the analyses shows that tower response under multiple-point wind-field simulation results in lower responses when compared to that of single-point simulation.

Seismic Performance and Vibration Control of Urban Over-track High-rise Buildings

  • Ying, Zhou;Rui, Wang;Zengde, Zhang
    • International Journal of High-Rise Buildings
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    • v.11 no.3
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    • pp.207-219
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    • 2022
  • During the structural design of urban over-track high-rise buildings, two problems are most likely encountered: the abrupt change of story stiffness between the podium and the upper towers, as well as the demand for train-induced vibration control. Traditional earthquake-resistant structures have to be particularly designed with transfer stories to meet the requirement of seismic control under earthquakes, and thus horizontal seismic isolation techniques are recommended to solve the transfer problem. The function of mitigating the vertical subway-induced vibration can be integrated into the isolation system including thick rubber bearings and 3D composite vibration control devices. Engineering project cases are presented in this paper for a more comprehensive understanding of the engineering practice and research frontiers of urban over-track high-rise buildings in China.

A Unified Theoretical Treatment for Thermal Analysis of Cooling Towers, Evaporating Condensers, and Fluid Coolers (냉각탑, 증발식 응축기 및 밀폐식 냉각탑의 전열해석을 위한 통일이론)

  • Ryu, Hae-Seong
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.15 no.1
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    • pp.67-81
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    • 1986
  • 냉각탑, 밀폐식냉각탑, 증발식응축기는 증발식냉각기의 분류에 속한다. 열은 증발에 의해 제거되어, 중력에 따라 유하하는 수 film으로 부터 충전물, 또는 밀폐식냉각탑, 증발식응축기의 관군상을 흐르는 공기에 전달된다. 따라서 공기측에서의 열과 물질의 이동프로세스는 기본적으로는 동일하다. 각 형식에서의 차이는 냉각되는 유체측에서의 열저항의 형태가 다르다는 점이다. 이 무저항은 냉각탑에서는 아주 작으나 다른 두 경우에 있어서는 계산상 고려하지 않으면 안된다. 이 논문은 이들 세 형식에 대해 통일된 이론을 적용할 수 있다는 것을 보여주기 위한 것이다. 그러므로 열 및 물질이동저항의 계산을 위한 식에 대해 논의하고 있다. 또한 복잡성을 피하기 위해, Merkel의 근사식을 공기측의 열 및 물질이동계산에 이용하였다.

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Shenzhen Rural Commercial Bank Headquarters: an Iconic Tower Defined by the Integration of Architecture, Structure and Sustainability Goals

  • Besjak, Charles;Thewis, Alexandra
    • International Journal of High-Rise Buildings
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    • v.11 no.1
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    • pp.31-39
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    • 2022
  • The seamless integration of the architecture and structure of a tall building plays a key role in establishing a recognizable and iconic design. The structural system developed for Shenzhen Rural Commercial Bank Headquarters (SRCBH) utilizes enhanced structural innovations unique to the tower's geometry to improve structural and sustainability performance. SRCBH utilizes a steel diagrid system pulled outside of the enclosure line with diaphragm forces resolved primarily by corner diagonal beams. During the design process the structural systems underwent performance based design and optimization for wind and seismic loading. Resiliency was prioritized for structural design as well as fire resistance. More closely integrating the structure of a building with its architecture and sustainability goals can lead to unique and innovative towers with a timeless expression.

Reaching New Heights in Timber-Hybrid Design: Designing the Netherlands' Tallest Timber-Hybrid Residential Building

  • Pascal Steenbakkers;Babette Verheggen;Mathew Vola;Do Janne Vermeulen
    • International Journal of High-Rise Buildings
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    • v.13 no.2
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    • pp.195-204
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    • 2024
  • HAUT, a residential tower, is a prototype for building innovative and environmentally-friendly high-rise timber structures. The team - Arup, Team V Architecture, Lingotto and JP van Eesteren - designed and built an ambitious sustainable building: a timber skyscraper, with 21 floors one of the tallest timber hybrid towers in the world. Never before has this highest sustainability rating - BREEAM Outstanding - been awarded to a residential building in the Netherlands. As a result of the new techniques for a timber hybrid tower of 73 meters high, there is interest from all over the world for this combination of sustainability and urban densification.

A Study on Commemoration Characteristics of Vietnam War Memorials in Korea (한국에 있는 베트남전쟁 메모리얼에 나타난 기념성)

  • Lee, Sang-Seok
    • Journal of the Korean Institute of Landscape Architecture
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    • v.44 no.4
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    • pp.22-34
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    • 2016
  • The purpose of this study was to analyze commemoration characteristics of fifty-nine Vietnam war memorials in Korea(VWMK) including monuments and national cemeteries from landscape architectural point of view such as location, spacial characteristic, landscape detail, sculpture, and interpretive text. Based on the commemoration characteristics of the analysis, the commemoration culture among Vietnam, the U.S.A., and Korea were studied and differences compared. The results are as follows. First, monuments were mainly located in public open space such as national cemeteries, parks, and plaza, and some of them were elected along with Korea war memorials to honor Vietnam war veterans at the national level. Second, because the monuments were relatively small and memorial towers were conventionally built on a square platform, the memorial style had been simply standardized to stereotype the commemoration characteristics. Third, outmoded memorial towers, stone plates, emblems, and memorial walls were used as main landscape details and standardized facilities were considered from an artistic and social point of view. Fourth, realistic soldier statues to show heroic and humanitarian image were in majority, while symbolic and abstract sculpture were small in number, they were mostly conventional and unexpressive. Fifth, the causes of participation in the Vietnam War were predominantly expressed as 'defending freedom', 'keeping world peace', and 'national economic development' based on anti-communism and patriotism, and also the collectivity of Vietnam War veterans by troop and local level was emphasized through engraving each veterans's name on towers, plates, and walls. VWMK are mostly conventional and stereotyped in style and show strongly national official memory and the collectivity of veterans from a sociopolitical perspective, and aim for anti-communistic patriotism ideologically. Further study and projects will be required to make creative and innovative memorials and to study how to rethink sublime fundamental themes like war, death, and the individual veteran's experience in VWMK.

Seismic Response Control of Cable-Stayed Bridge using Fuzzy Supervisory Control Technique (퍼지관리제어기법을 이용한 사장교의 지진응답제어)

  • Park, Kwan-Soon;Koh, Hyun-Moo;Ok, Seung-Yong;Seo, Chung-Won
    • Journal of the Earthquake Engineering Society of Korea
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    • v.8 no.4
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    • pp.51-62
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    • 2004
  • Fuzzy supervisory control technique for the seismic response control of cable-stayed bridges subject to earthquakes is studied. The proposed technique is a hybrid control method, which adopts a hierarchical structure consisting of several sub-controllers and a fuzzy supervisor. Sub-controllers are independently designed to reduced the responses to be controlled of a cable-stayed bridge, and a fuzzy supervisor achieves improved seismic control performance by tuning the pre-designed sub-controllers. It is realized by converting static gains of the sub-controllers into time-varying dynamic gains through the fuzzy inference mechanism. To evaluate the feasibility of the proposed technique, the benchmark control problem of cable-stayed bridge proposed by Dyke et al. is adopted. The control variables for the seismic response control of the cable-stayed bridge are determined to be t도 shear forces and bending moments at the base of the towers, the longitudinal displacements at the top of the towers, the relative displacements between the deck and the tower, and the tensions in the stay cables. Comparative results between the fuzzy supervisory controller and LQG controller demonstrate the effectiveness of the proposed control technique.

Dynamics of Turbid Water in a Korean Resernvoir with Selective Withdrawal Discharges (선택 취수하는 저수지에서 탁수의 동태)

  • Shin, Jae-Ki;Jeong, Seon-A;Choi, Il-Hwan;Hwang, Soon-Jin
    • Korean Journal of Ecology and Environment
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    • v.37 no.4 s.109
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    • pp.423-430
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    • 2004
  • This study intended to understand movements of turbid water in selective with drawal reservoirs before and after summer monsoon. Mean rainfall during November-May was low, compared to that during June-October. The reservoir water was discharged through watergates when previous rainfall and inflow exceeded 50 mm and $80\;m^3s^{-1}$, respectively. Intake towers were generally used except for the period of the high runoff. Average turbidity in gown-reservoir showed a difference of 29.9 NTU between premonsoon and postmonsoon. Diameter of particles of turbid water ranged between 0.435 and $482.9\;{\mu}m$. Fine particles such as clay were much denser than the larger particle. In the whole stations, clay component was relatively higher with a proportion of that in the particle distribution. Particle composition of turbid water showed that clay consisted of 94.4-98.9% and silt made of 1.1-5.6%. Analysis on turbid water movements derived from particle distribution showed a linear increase from the deep layer toward the surface layer in lower area of a reservoir. This was closely related with the hydraulic behavior of the reservoir, and heavily affected by the discharges through selective withdrawal towers and watergates. Turbid water originated from stream sediments in the middle area then resuspended in the down-reservoir causing a movement between the surface and middle layers of the reservoir. Therefore, such phenomenon needs to be understood for reservoir water quality management.