• Proceedings of the KSME Conference
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• 2001.06a
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• pp.837-841
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• 2001

The column-type sensing element in building and mechanical construction parts was designed as three forces and three moments sensor by attaching strain gages approximately. Compared to conventional multi-component sensor, the designed sensor can solve the problem about low stiffness and high cost. The radius of the column was designed analytically and compared with finite element analysis. The coupling errors between components were minimized by using addition and subtraction procedure of signals. The fabricated sensor was tested by using a deadweight force standard machine and a six-component force calibration machine in Korea Research Institute of Standards and Science(KRISS). The calibration showed that the multi-component force/moment sensor had coupling error less than 19.8 % between $F_x$ and $M_y$ components, and 9.0 % in case of other components.

• Earthquakes and Structures
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• v.9 no.3
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• pp.625-637
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• 2015

It is usual in design and assessment of structures to isolate the effects of vertical and horizontal excitations by ignoring their coupling effects. In this situation, total structural response is obtained by employing the well-known combination rules whereby independent assumed response components of earthquakes are combined. In fact, the effects of the simultaneity of the ground motion components are ignored. In this paper, the effect of vertical excitation on horizontal response of structures, the coupling of vertical and horizontal responses, has been evaluated. A computer program is prepared to perform nonlinear dynamic analysis based on the derived governing equations of coupled motions. In the case of simultaneous excitation the results show significant increases in spectral displacement in some periods of vibration in comparison to only horizontally excited systems. Moreover, whenever ratio of the vertical peak ground acceleration to horizontal one become larger, the significant increase in horizontal spectral displacements are observed.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.7
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• pp.621-628
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• 2016

This paper presents the development of a deadweight type 6-component force/moment generator for estimating characteristics of multi-component loadcell. Several new methods in moment generation are introduced in order to produce accurate force / moment and to minimize coupling effect between each force or moment components. In order to verify the reliability of the calibration system developed, estimation of the method for generating moment components and cross measurements between force or moment components are carried out utilizing a commercial torque cell and both-ends fixed beam designed in this paper.

• Steel and Composite Structures
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• v.7 no.4
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• pp.279-301
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• 2007

When coupling beams are proportioned appropriately in coupled core wall (CCW) systems, the input energy from ground motions is dissipated primarily through inelastic deformations in plastic hinge regions at the ends of the coupling beams. It is desirable that the plastic hinges form at the beam ends while the base wall piers remain elastic. The strength and stiffness of the coupling beams are, therefore, crucial if the desired global behavior of the CCW system is to be achieved. This paper presents the results of nonlinear response history analysis of two 20-story CCW buildings. Both buildings have the same geometric dimensions, and the components of the buildings are designed based on the equivalent lateral force procedure. However, one building is fitted with steel coupling beams while the other is fitted with diagonally reinforced concrete coupling beams. The force-deflection relationships of both beams are based on experimental data, while the moment-curvature and axial load-moment relationships of the wall piers are analytically generated from cross-sectional fiber analyses. Using the aforementioned beam and wall properties, nonlinear response history analyses are performed. Superiority of the steel coupling beams is demonstrated through detailed evaluations of local and global responses computed for a number of recorded and artificially generated ground motions.

• ETRI Journal
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• v.36 no.5
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• pp.847-855
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• 2014

We developed a highly refractive index planarization layer showing a very smooth surface for organic light-emitting diode (OLED) light extraction, and we successfully prepared a highly efficient white OLED device with an embossed nano-structure and highly refractive index planarization layers. White OLEDs act as an internal out-coupling layer. We used a spin-coating method and two types of $TiO_2$ solutions for a planarization of the embossed nano-structure on a glass substrate. The first $TiO_2$ solution was $TiO_2$ sol, which consists of $TiO_2$ colloidal particles in an acidic aqueous solution and several organic additives. The second solution was an organic and inorganic hybrid solution of $TiO_2$. The surface roughness ($R_a$) and refractive index of the $TiO_2$ planarization films on a flat glass were 0.4 nm and 2.0 at 550 nm, respectively. The J-V characteristics of the OLED including the embossed nano-structure and the $TiO_2$ planarization film were almost the same as those of an OLED with a flat glass, and the luminous efficacy of the aforementioned OLED was enhanced by 34% compared to that of an OLED with a flat glass.

• Journal of Korea Multimedia Society
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• v.14 no.2
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• pp.318-328
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• 2011

This paper suggests a comprehensive method to describe architectural components for supporting Korean Traditional Building design with only small components set in CAD system. Korean traditional buildings can be classified variously based on the their size, usage and structure type(whether ornament part, namely Gongpo, is in there or not). Moreover components can be varied according to the combining rule between them. If all of these components are presented, these tremendous components rather prevent the efficient design of traditional buildings. In order to solve this problem we present object-oriented approach to describe versatile components as one template if they are same in functional aspects. From the template, many similar instances can be derived according to the attribute value. The templates are designed in order to reflect the coupling scheme between components in the relative parameters of the templates. It leads effects of minimizing error which can be occurred frequently in the process of traditional building design.

• ETRI Journal
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• v.29 no.6
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• pp.811-813
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• 2007

We report on a ridge waveguide laser diode with laterally tapered waveguides fabricated in a single growing step using a double patterning method. In this structure, nearly constant output power is obtained with the change of the lower tapered waveguide width, and the facet power ratio of 1.4 to 1.5 is observed over the current range. The asymmetric facet power property is also investigated.

• International journal of steel structures
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• v.18 no.4
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• pp.1200-1209
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• 2018

In this study, a probabilistic framework of the damage assessment of pipelines subjected to extreme hazard scenario was developed to mitigate the risk and enhance design reliability. Nonlinear 3D finite element models of T-joint systems were developed based on experimental tests with respect to leakage detection of black iron piping systems, and a damage assessment analysis of the vulnerability of their components according to nominal pipe size, coupling type, and wall thickness under seismic wave propagations was performed. The analysis results showed the 2-inch schedule 40 threaded T-joint system to be more fragile than the others with respect to the nominal pipe sizes. As for the coupling types, the data indicated that the probability of failure of the threaded T-joint coupling was significantly higher than that of the grooved type. Finally, the seismic capacity of the schedule 40 wall thickness was weaker than that of schedule 10 in the 4-inch grooved coupling, due to the difference in the prohibition of energy dissipation. Therefore, this assessment can contribute to the damage detection and financial losses due to failure of the joint piping system in a liquid pipeline, prior to the decision-making.

• Journal of Information Display
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• v.10 no.2
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• pp.92-95
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• 2009

Highly efficient blue and white phosphorescent organic light-emitting diodes (PHOLEDs) with an exciton-confining structure were investigated in this study. Effective charge confinement was achieved by stacking two emitting layers with different charge-transporting properties, and blue PHOLEDs with a maximum luminance efficiency of 47.9 lm/W were developed by using iridium(III) bis(4,6-(difluorophenyl) pyridinato-N,C2')picolinate (FIrpic) as an electrophosphorescent dopant. Moreover, when the optimized green and red emitting layers were sandwiched between the two stacked blue emitting layers, white PHOLEDs (WOLEDs) with peak external and luminance efficiencies of 19.0% coupling technique.and 54.0 lm/W, respectively, were obtained without the use of any out-coupling technique.

• Textile Coloration and Finishing
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• v.13 no.5
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• pp.48-48
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• 2001

The effects of silane coupling agent on the performance properties of cotton fabrics treated with loess and its washing durability were investigated. Mean average diameter of loess was 17.88㎛ and main components were SiO₂, Al₂O₃ and Fe₂O₃. By using the cationic agent, the dyeability of cotton fabrics was improved. The washing durability, antibacterial property and deodorization rate were improved and very good emissivities of far infra-red rays were obtained by using the silane coupling agent. And also the mechanical properties of cotton fabrics, such as primary hand values, were improved.