• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.859-864
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• 2001

An effective live load model for analyzing probable maximum live load effects such as moment and shear in transverse direction was developed. The main procedure of this live load model is composed of four parts, i.e., firstly, determination of the appropriate influence lines in longitudinal direction, secondly, application of the characteristics of vehicles and traffic patterns in longitudinal direction, thirdly, determination of the appropriate influence lines in transverse direction, and fourthly, application of the characteristics of vehicles and traffic patterns in transverse direction. Through this procedure, the probabilistic distributions of maximum probable load effects are deduced in the form of probability density function (PDF) and/or cumulative density function(CDF). This live load model is able to consider local or global deterioration of bridges in the structural analysis.

• Journal of KSNVE
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• v.5 no.2
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• pp.247-256
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• 1995

In this paper, double exposure holographic interferometry using ruby pulse laser is formed in order to investigate the propagation of transient waves. The vibration characteristics according to the change of impact load direction, i.e., impacted in the shear direction and in the normal direction are analyzed. It was observed that the macroscopic trends of transient wave generation and propagation in the assembly of precipitator plates were almost similar regardless of the change of impact load direction. But the propagation and mixing of transient wave was advanced relatively slowly when impacted in the normal direction.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.5
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• pp.685-691
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• 2013

A load-cell-type anemovane operates based on wind vector properties. The developed load-cell-type anemovane is of a fixed type in which the wing does not rotate, unlike in the case of existing anemovanes. The load-cell-type anemovane is required to accurately derive the correlation between the load ratio and the wind direction in order to develop a qualified product. This is because the load ratio repeats every $90^{\circ}$ owing to the use of four load cells, and its value varies nonlinearly according to the wind direction. In this study, we compared analytical results with experimental results. Fluid analysis was carried out using ANSYS CFX. Furthermore, the prototype was tested using a self-manufactured wind tunnel. The wind direction was selected as the design variable. 13 selected wind direction conditions ranging from $0^{\circ}$ to $90^{\circ}$ with an interval of $7.5^{\circ}$ for analysis were defined. Furthermore, 10 wind direction conditions with an interval of $10^{\circ}$ for the experiment were defined. We derived the relations between the pressure ratio and the wind direction through the experiment and fluid analysis.

• Journal of Navigation and Port Research
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• v.36 no.5
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• pp.357-361
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• 2012

Anemometer is a meteorological instrument that measures wind direction and wind speed in real time, and is mounted to the cranes that are used at ports, shipbuilding yards, off-shore structure, or construction sites that are influenced by wind, and it is used in conjunction with the safety system. Load cell-type anemometer measures the wind direction through the ratio of load between 4 positions by mounting the thin plate to 4 load cells, and measures wind velocity through the summation of loads. In this study, we compared and analyzed the results in the theoretic approach, analytic approach and experimental approach to derive the correlation between load ratio and wind direction. Wind direction was selected as the design variable, and selected 9 wind direction conditions from $0^{\circ}{\sim}90^{\circ}$ with $11.25^{\circ}$ space for analysis, and 10 wind direction conditions with $10^{\circ}$ space for experiment.

• Journal of Korean Association for Spatial Structures
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• v.18 no.3
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• pp.133-140
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• 2018

Vertical earthquake motions can occur along with horizontal earthquakes, so that Structure should be designed to resist Seismic loads in all directions. Especially, due to the dynamic characteristics such as the vibration mode, when the vertical seismic load, the dynamic response of the Spatial structure is large. In this study, the seismic response of the lattice dome to horizontal and vertical seismic loads is analyzed, and a reasonable seismic load combination is analyzed by combining horizontal and vertical seismic response results. In the combination of the horizontal seismic load, the largest result is obtained when the direction of the main axis of the structure coincides with the direction of seismic load. In addition, the combination of vertical seismic load and horizontal seismic load was the largest compared with the combination of horizontal seismic load. Therefore, it is considered that the most reasonable and stable design will be achieved if the seismic load in vertical direction is considered.

• Journal of Korean Association for Spatial Structures
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• v.21 no.1
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• pp.51-59
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• 2021

In this paper, the effect of the turbulence intensity in across-wind direction on the wind load in CFD(Computational fluid dynamics) simulation was analyzed. 'Ansys fluent' software was used for CFD simulation. And the fluctuating wind speed applied to the simulation was generated according to Korean Design Standard and Von Karman wind turbulence model. The turbulence intensity in across-wind direction for simulation was applied from 0 to 100% of the turbulence intensity in along-wind direction. The analysis results showed that the turbulence intensity in across-wind direction had a particularly great effect on the wind load in across-wind direction.

• Journal of the Korea Furniture Society
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• v.17 no.1
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• pp.1-10
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• 2006

Movement behavior, shrinkage and equilibrium moisture content (EMC), in this experiment reflected a change of hygroscopicity mainly affected by continuously compressive load during radio-frequency/vacuum (RF/V) drying and humidity changes during equilibrating. As a result of interaction of the compressive load and moisture content changing under the RF/V condition, the shrinkages in loading direction were significantly increased while those perpendicular to loading direction were decreased. The shrinkages were affected most in tangential, and least in longitudinal direction. The shrinkages showed higher values in continuous drying than in intermittent drying. In the direction of increased shrinkage, all the movements were also increased, for example, the tangential movement for the loaded-RS and the radial movement for loaded-TS; in the direction of decreased shrinkage, all the movements except the tangential movement for the loaded-TS were decreased such as the tangential and radial movements for the loaded-ES, and the radial movement for the loaded-RS, comparing with those of the load-free. EMCs of the loaded specimens were all higher than that of the load-free specimen, and the highest for the loaded-TS, the lowest for the loaded-ES. The transverse hygroscopicity of specimen was reduced for the loaded-ES, but increased for the loaded-TS.

• KCI Concrete Journal
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• v.12 no.2
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• pp.55-72
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• 2000

This paper proposes a mechanical model to describe the load-deformation responses of the reinforced concrete plate members under service load state. An Analytical method is introduced on the basis of the rotating crack model which considers equilibrium, compatibility conditions, load-strain relationship of cracked member, and constitutive law for materials. The tension stiffening effect in reinforced concrete structures is taken into account by the average tensile stress-strain relationship from the load-strain relationship for the cracked member and the constitutive law for material. The strain compatibility is used to find out the crack direction because the crack direction is an unknown variable in the equilibrium and compatibility conditions. The proposed theory is verified by the numerous experimental data such as the crack direction, moment-steel strain relationship, moment-crack width relationship. The present paper can provide some basis for the provision of the definition of serviceability for plate structures of which reinforcements are deviated from the principal stresses, because the present code defines the serviceability by the deflection, crack control, vibration and fatigue basically for the skeletal members. The proposed theory is applicable to predict the service load state behavior of a variety of reinforced concrete plate structures such as skew slab bridges, the deck of skew girder bridges.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.19 no.2
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• pp.140-145
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• 2023

When performing stress analysis for a nozzle in nuclear power plants, the nozzle loads should be determined conservatively. Existing stress analysis report of 3-D nozzle loads in nuclear power plants often provide only load magnitude not the sign (direction). Since calculated stress distribution depends on load direction, determining critical load directions for conservative stress analysis is crucial. In this study, an efficient method for determining critical load directions in nozzle loads is proposed. In the proposed method, stresses are firstly calculated using elastic finite element (FE) analysis for the uni-axial load in each direction. Then stress distributions for the multi-axial loads are analytically calculated using the principle of superposition. The calculated stress values are verified by comparing with FE analysis results under multi-axial loading. By using this method, the complex task of determining conservative load directions can be simplified.

• The Journal of Korean Physical Therapy
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• v.21 no.2
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• pp.97-101
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• 2009

Purpose: This study examined how the direction of carrying a load affects the foot stability and kinesiology while walking. Methods: The heel rotation, Hallux stiffness, foot balance, metatarsal load, toe out angle, subtalar joint flexibility were measured in 40 adults (men and women) who carried a load back and forth, walking on a 2-meter-long board. The measurement was carried out three times and the mean of the measurements was used to compare the difference between the front, back and the condition without a load. Results: While walking, heel rotation and hallux stiffness occurred most when a front load was applied compared to a back load or no load condition (p<0.05). A metatarsal load also appeared to be the highest with the frond load, but there was no significant difference in the balance of the whole foot. Both the toe out angle and subtalar joint flexibility appeared to increase significantly (p<0.05). Conclusion: Applying the front load causes subtalar joint instability and increases the plantar foot pressure imbalance during walking.