• Wind and Structures
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• v.30 no.1
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• pp.99-117
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• 2020

This paper focuses on the processes of wind flow in atmospheric boundary layer, to produce realistic full scale pressures for design of low-rise buildings. CFD with LES turbulence closure is implemented on a scale 1:1 prototype building. A proximity study was executed computationally in CFD with LES that suggests new recommendations on the computational domain size, in front of a building model, apart from common RANS-based guidelines (e.g., COST and AIJ). Our findings suggest a location of the test building, different from existing guidelines, and the inflow boundary proximity influences pressure correlation and reproduction of peak loads. The CFD LES results are compared to corresponding pressures from open jet, full scale, wind tunnel, and the ASCE 7-10 standard for roof Component & Cladding design. The CFD LES shows its adequacy to produce peak pressures/loads on buildings, in agreement with field pressures, due to its capabilities of reproducing the spectral contents of the inflow at 1:1 scale.

• Proceedings of the KIEE Conference
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• 2007.10c
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• pp.247-249
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• 2007

Urban dynamometer driving schedule(FTP-75 mode) plays very significant role on automotive emission test, due to reference point. The overall system energy efficiency of a HEV(Hybrid Electric Vehicle) is highly dependent on the energy management strategy employed. An energy source is the heart of a HEV. In order to applicable to a vehicle component, it must be need to real world test result. But, the present state of things have numerous problems. In this paper, be studied performed based on HEV simulation software in virtual world and chassis dynamometer test in real world and the result make a comparative. Toyota Prius vehicle was adapted as a modeling and real testing to evaluate the hybrid components and energy balancing management. The point at issue is voltage and current analysis for HEV battery SOC(State of Charge), and verification for energy.

• Geomechanics and Engineering
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• v.18 no.5
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• pp.459-469
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• 2019

It is important to estimate the shear strength of shallow compacted soils as a construction material. A series of constant water content triaxial compression (CWCC) tests under low confining state in this study were performed on compacted geomaterials. For establishing a relationship of the shear strengths between saturated and unsaturated states on compacted geomaterials, the suction stresses were derived by two methods: the conventional suction-measured method and the Suction stress-SWRC Method (SSM). Considering the suction stress as an equivalent confining stress component in the (${\sigma}_{net}$, ${\tau}$) plane, it was found that the peak deviator stress states agree well with the failure line of the saturated state from the triaxial compression test when the SSM is applied to obtain the suction stress. On the other hand, the cavitation phenomenon on the measurement of suction affected the results of the conventional suction-measured method. These results mean that the SSM is distinctly favorable for obtaining the suction value in the CWCC test because the SSM is not restricted by the cavitation phenomenon. It is expected that the application of the SSM would reduce the time required, and the projected cost with the additional equipment such as a pore water measuring device in the CWCC test.

• Journal of Society of Preventive Korean Medicine
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• v.21 no.2
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• pp.35-44
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• 2017

Objectives : The purpose of this study was to investigate the association between quality of life and Mibyeong index of abnormal symptoms by the Mibyeong state. Methods : A total of 1,100 people were recruited into this study and were collected by specialized research company. The data were collected by personal information using MBI(Mibyeong Index) and SF-12 (Short form-12) and were analyzed with SPSS (version 21.0) computer program, and included Pearson's chi-square test, ANOVA, Pearson's correlation coefficient, and multiple regression analysis. Results : The Mibyeong Index which represents abnormal symptom type showed significant difference for Mibyeong state (p<.001). In Total subject, fatigue, pain, low sleep quality and indigestion were found to be significant predictors of PCS(Physical Component Summary). In Healthy group, pain was found to be significant predictor of PCS. In MI 1 group, fatigue, pain, indigestion and anxiety were found to be significant predictors of PCS. In MI 2 group, fatigue, pain and low sleep quality were found to be significant predictors of PCS. In Total subject, fatigue, depression, anger and anxiety were found to be significant predictors of MCS (Mental Component Summary). In Healthy group, indigestion and anxiety were found to be significant predictors of MCS. In MI 1 group, depression and anger were found to be significant predictors of MCS. In MI 2 group, fatigue and depression were found to be significant predictors of MCS. Conclusions : The relationship between Quality of life and MBI changes according to Mibyeong state. We expect that this result could be contribute to health management of people in Mibyeong state.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.4
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• pp.25-33
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• 2000

The reorientations of the atoms by frictional shear deformation at the surface induce cracks at the boundary of the grain. The cracks grow and propagate in regions where the hydrostatic component of stress is least compressive because the compressive component restores the cracks by three-dimensional crystallizing $\pi$-bondings. The materials with Lder's band have very small amount of wear at the initial state. It suggests that initial frictional shear deformation be consumed to the formation of the Lder's band. The average wear amounts of the materials increase very steeply as the øu the stress-strain ratio at the ultimate point, decreases.

• Structural Engineering and Mechanics
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• v.17 no.1
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• pp.29-50
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• 2004

A total life model was developed to assess the service life of aging aircraft. The primary focus of this paper is the development of crack growth life projection using the response surface method. Crack growth life projection is a necessary component of the total life model. The study showed that the number of load cycles N needed for a crack to propagate to a specified size can be linearly related to the geometric parameter, material, and stress level of the component considered when all the variables are transformed to logarithmic values. By the Central Limit theorem, the ln N was approximated by Gaussian distribution. This Gaussian model compared well with the histograms of the number of load cycles generated from simulated crack growth curves. The outcome of this study will aid engineers in designing their crack growth experiments to develop the stochastic crack growth models for service life assessments.

• Korean Journal of Metals and Materials
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• v.48 no.6
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• pp.489-497
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• 2010

The remaining life estimation of the level luffing crane component, which has operated for about 20 years is examined carefully, especially on the crane structures. To analyse the crane sructures, the basic load and load combination needed to be considered. We modeled various parts of the level luffing crane to analyse fatigue. Fatigue analysis results showed that the level luffing crane is in the fatigue life so that the crane is in the safe state in fatigue cumulative damage. Analysis results show that the remaining life of a jib upper beam would be about 10 years therefore, the level luffing crane should be stable for fatigue for that period.

• International Journal of High-Rise Buildings
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• v.10 no.3
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• pp.211-218
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• 2021

A new type of earthquake resilient reinforced concrete (RC) shear wall structure, installed with replaceable coupling beams and replaceable corner components at the bottom of wall piers, is proposed in this study. At first, the mechanical behavior of replaceable components, such as combined dampers and replaceable corner component, is studied by cyclic loading tests on them. Then, cycling loading tests are conducted on one conventional coupled shear wall and one new type of coupled shear wall with replaceable components. The test results indicate that the damage of the new type of coupled shear wall concentrates on replaceable components and the left parts are well protected. Finally, a case study is introduced. The responses of one conventional frame-tube structure and one new type of structure installed with replaceable components under the wind and the earthquake are compared, which verify that the performance of new type of structure is much better than the conventional structure.

• Communications for Statistical Applications and Methods
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• v.30 no.3
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• pp.311-330
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• 2023

The present work describes simulation studies to compare the performances in terms of averaged mean squared error of bayesian wavelet shrinkage methods in estimating component curves from aggregated functional data. Five bayesian methods available in the literature were considered to be compared in the studies: The shrinkage rule under logistic prior, shrinkage rule under beta prior, large posterior mode (LPM) method, amplitude-scale invariant Bayes estimator (ABE) and Bayesian adaptive multiresolution smoother (BAMS). The so called Donoho-Johnstone test functions, logit and SpaHet functions were considered as component functions and the scenarios were defined according to different values of sample size and signal to noise ratio in the datasets. It was observed that the signal to noise ratio of the data had impact on the performances of the methods. An application of the methodology and the results to the tecator dataset is also done.

• Transactions of Materials Processing
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• v.20 no.3
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• pp.222-228
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• 2011

This paper is a review of biaxial tensile test equipments and specimens. The stresses acting on a component in service are multiaxial in nature. Therefore, it is necessary to consider the mechanical properties of sheet materials not only under uniaxial but also under these multiaxial stress states. Biaxial testing of metal in industry becomes an important investigation tool for the evaluation of mechanical properties of sheet metals. In this paper, several types of biaxial tensile tests were reviewed, and their advantages and limitations were discussed.