• Steel and Composite Structures
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• 제1권2호
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• pp.171-185
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• 2001

The design of tall buildings has recently provided many challenges to structural engineers. One such challenge is to minimise the cross-sectional dimensions of columns to ensure greater floor space in a building is attainable. This has both an economic and aesthetics benefit in buildings, which require structural engineering solutions. The use of high strength steel in tall buildings has the ability to achieve these benefits as the material provides a higher strength to cross-section ratio. However as the strength of the steel is increased the buckling characteristics become more dominant with slenderness limits for both local and global buckling becoming more significant. To arrest the problems associated with buckling of high strength steel, concrete filling and encasement can be utilised as it has the affect of changing the buckling mode, which increases the strength and stiffness of the member. This paper describes an experimental program undertaken for both encased and concrete filled composite columns, which were designed to be stocky in nature and thus fail by strength alone. The columns were designed to consider the strength in axial compression and were fabricated from high strength steel plate. In addition to the encased and concrete filled columns, unencased columns and hollow columns were also fabricated and tested to act as calibration specimens. A model for the axial strength was suggested and this is shown to compare well with the test results. Finally aspects of further research are addressed in this paper which include considering the effects of slender columns which may fail by global instabilities.

• 한국안전학회지
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• 제36권2호
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• pp.26-31
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• 2021

Buildings with glass curtain walls have become popular due to their appealing aesthetics and ability to let in natural light. However, light reflection from the glass surface is unavoidable in these buildings. In particular, the reflection of light from the glass envelope can create afterimage glare, a hazard to nearby drivers and pedestrians. Despite this potential danger, glare from buildings with curtain walls has not been well-studied. Hence, we analyzed the effect of light reflection on glare around a glass-enclosed skyscraper, depending on its surface reflectance. We investigated the potential hazard of glare to drivers using a commercially available software program. The results indicate that the direction of light reflection is distinctive when the incident angle of solar light increases. Moreover, this light reflection is high enough to induce an afterimage to drivers and pedestrians near the building. We found that keeping the reflectance of the building surface under 3% is required to minimize the afterimage hazard to drivers. Consequently, we recommend managing glass reflectance and installing additional traffic safety systems to reduce traffic accidents near curtain wall buildings.

• 한국산업융합학회 논문집
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• 제25권3호
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• pp.407-415
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• 2022

In this study, a square rounding sidewalk block frame was developed considering the simplicity of construction and the superiority of aesthetics. In addition, it is possible to prevent damage, deformation, and settlement of adjacent sidewalk blocks due to plastic deformation during car impact load of installed bollad. A non-linear structural analysis was performed through finite element analysis to examine the performance of a car crash to which this was applied. Structural safety was confirmed through car crash simulation according to the direction of impact, and it is estimated that the function can be restored by replacing some parts in case of damage due to impact.

• 반도체디스플레이기술학회지
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• 제22권4호
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• pp.48-52
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• 2023

From the past to the present, banners are consistently used as effective advertising means. In the case of Korea, there are frequent situations in which hidden advertisements are installed. As a result, such hidden advertisement materials may damage urban aesthetics and moreover, incur unnecessary manpower consumption and waste of money. The proposed method classifies the detected banners into good banner and bad banner. The classification results are based on whether the relevant banners are installed in compliance with legal guidelines. In the process, YOLO and Open Computer Vision library are used to determine from various perspectives whether banners in CCTV images comply with the guidelines. YOLO is used to detect the banner area in CCTV images, and OpenCV is used to detect the color values in the area for color comparison. If a banner is detected in the video, the proposed method calculates the location of the banner and the distance from the designated bulletin to determine whether it was installed within the designated location, and then compares whether the color used in the banner is complied with local government guidelines.

• 한국의류산업학회지
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• 제20권3호
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• pp.245-256
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• 2018

This study considers application types and meanings of fashion engineering by analyzing CuteCircuit. The conclusions of this study are as follows. The application type of fashion engineering shown in CuteCircuit is first, electronic fashion, which attaches LED or WL on the surface of clothes to express the decorative function in clothes as optical light change, ultimately performing one-dimensional function. Second, interactive fashion is a medium in which clothing connects human beings with other human beings with sensors that can recognize the changes in tactile or movement with the wearer or with a light source that can visualize the emotional changes of the wearer. Third, scientific fashion has emerged as a new type of fashion in which new materials introduced in the field of engineering are fused with clothing to expand functionality and aesthetics. The meanings of fashion engineering in CuteCircuit is first, trying to conceptualize a new beauty as an open fashion that can freely change with the creation of a dual beauty by combining analog and digital sensibility. Second is the external representation of human psychological change or emotional exchange, which helps to form a consensus by understanding and exchanging emotions of different people. Third, reorganization of apparel pursuing integrated value appeared. Clothing, as a connection body in which the human body and the mechanical environment are combined with each other, is reestablished as a product of variable body that can embody an integrated value that includes various characteristics and can be diversified appropriately in any circumstance.

• 한국재료학회지
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• 제23권8호
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• pp.441-446
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• 2013

There is increasing interest in zirconia as a dental material due to its aesthetics, as well as the exceptionally high fracture toughness and high strength that are on offer when it is alloyed with certain oxides like yttria. In recent years, many solution based chemical synthesis methods have been reported for synthesis of zirconia, of which the sol-gel method is considered to be best. Here, we synthesize zirconia by a sol gel assisted precipitation method using either PEG or PVA as a stabilizing agent. Zirconia sol is first synthesized using the hydrothermal method. We used NaOH as the precipitating agent in this method because it is easy to remove from the final solution. Zirconium and yttrium salts are used as precursors and PEG or PVA are used as stabilizers to separate the metal ions. The resulting amorphous zirconia powder is calcined at $900^{\circ}C$ for 2 h to get crystallized zirconia. XRD analysis confirmed the partially stabilized zirconia synthesis in all the synthesized powders. SEM was taken to check the morphology of the powder synthesized using either PEG or PVA as a stabilizing agent and finally the transparency was calculated. The results confirmed that the powder synthesized with 10 % PVA as the stabilizing agent had highest percentage of transparency among all the synthesized powder.

• Wind and Structures
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• 제26권2호
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• pp.99-114
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• 2018

Due to shortage of land and architectural aesthetics, sometimes the buildings are constructed as unconventional in plan. The wind force acts differently according to the plan shape of the building. So, it is of utter importance to study wind force or, more specifically wind pressure on an unconventional plan shaped tall building. To address this issue, this paper demonstrates a comprehensive study on mean pressure coefficient of 'E' plan shaped tall building. This study has been carried out experimentally and numerically by wind tunnel test and computational fluid dynamics (CFD) simulation respectively. Mean wind pressures on all the faces of the building are predicted using wind tunnel test and CFD simulation varying wind incidence angles from $0^{\circ}$ to $180^{\circ}$ at an interval of $30^{\circ}$. The accuracy of the numerically predicted results are measured by comparing results predicted by CFD with experimental results and it seems to have a good agreement with wind tunnel results. Besides wind pressures, wind flow patterns are also obtained by CFD for all the wind incidence angles. These flow patterns predict the behavior of pressure variation on the different faces of the building. For better comparison of the results, pressure contours on all the faces are also predicted by both the methods. Finally, polynomial expressions as the sine and cosine function of wind angle are proposed for obtaining mean wind pressure coefficient on all the faces using Fourier series expansion. The accuracy of the fitted expansions are measured by sum square error, $R^2$ value and root mean square error.

• 한국화재소방학회논문지
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• 제32권1호
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• pp.40-45
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• 2018

무기재로서 질석은 친환경적인 특성과 내화, 단열, 흡음 뿐 만 아니라 결로방지, 탈취 및 미관 등이 우수하므로 건축마감재로서 활용될 경우 효용성이 높을 것으로 판단된다. 본 연구에서는 질석을 주원료로 하여 미네랄 루즈울(Mineral Loose Wool) 또는 미네랄 파우더(Mineral Powder)를 혼입한 건축용 마감보드를 개발하고 불연시험과 단열시험을 수행하였다. 시험결과 두 개의 질석보드 모두 불연재로서 성능을 확보하였으며 열전도율 0.086 및 $0.092W/m{\cdot}K$로 나타났다. 또한 개발된 두 개의 질석보드를 경골목구조 내화벽체 표준상세(KS F 1611-1)의 마감재로 적용하여 내화시험을 수행하였다. 내화시험결과 VB-L 시험체가 VB-P시험체 보다 내화성능이 다소 높게 나타났으며 두 개의 질석보드 모두 두께 30 mm로도 내화성능 2시간 확보가 충분한 것으로 나타났다.

• Structural Engineering and Mechanics
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• 제11권1호
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• pp.35-48
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• 2001

The objective of this study is to investigate the stability behavior of steel cable-stayed bridges by comparing the buckling loads obtained by means of finite element methods with eigen-solver. In recent days, cable-stayed bridges dramatically attract engineers' attention due to their structural characteristics and aesthetics. They require a number of design parameters and present a high degree of static indetermination, especially for long span bridges. Cable-stayed bridges exhibit several nonlinear behaviors concurrently under normal design loads due to the individual nonlinearity of substructures such as the pylons, stay cables, and bridge deck, and their interactions. The geometric nonlinearities arise mainly from large displacements of cables. Strong axial and lateral forces acting on the bridge deck and pylons cause structural nonlinear behaviors. The interaction is among the substructures. In this paper, a typical three-span steel cable-stayed bridge with a variety of design parameters has been investigated. The numerical results indicate that the design parameters such as the ratio of $L_1/L$ and $I_p/I_b$ are important for the structural behavior, where $L_1$ is the main span length, L is the total span length of the bridge, $I_p$ is the moment of inertia of the pylon, and $I_b$ is the moment of inertia of the bridge deck. When the ratio $I_p/I_b$ increases, the critical load decreases due to the lack of interaction among substructures. Cable arrangements and the height of pylon are another important factors for this type of bridge in buckling analysis. According to numerical results, the bridges supported by a pylon with harp-type cable arrangement have higher critical loads than the bridges supported by a pylon with fan-type cable arrangement. On contrary, the shape of the pylon does not significantly affect the critical load of this type of bridge. All numerical results have been non-dimensionalized and presented in both tabular and graphical forms.

• Smart Structures and Systems
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• 제15권1호
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• pp.151-167
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• 2015

Instrumentation on structural health monitoring system imposes critical issues for applying the structural monitoring system to real world structures, for which not only on the configuration and geometry, but also aesthetics on the system to be monitored should be considered. To illustrate this point, two real world structural health monitoring systems, the structural health monitoring system of Shenzhen Vanke Center and the structural health monitoring system of Shenzhen Bay Stadium in China, are presented in the paper. The instrumentation on structural health monitoring systems of real world structures is addressed by providing the description of the structure, the purpose of the structural health monitoring system implementation, as well as details of the system integration including the installations on the sensors and acquisition equipment and so on. In addition, an intelligent algorithm on stress identification using measurements from multi-region is presented in the paper. The stress identification method is deployed using the fuzzy pattern recognition and Dempster-Shafer evidence theory, where the measurements of limited strain sensors arranged on structure are the input data of the method. As results, at the critical parts of the structure, the stress distribution evaluated from the measurements has shown close correlation to the numerical simulation results on the steel roof of the Beijing National Aquatics Center in China. The research work in this paper can provide a reference for the design and implementation of both real world structural health monitoring systems and intelligent algorithm to identify stress distribution effectively.