• Steel and Composite Structures
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• v.26 no.1
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• pp.115-123
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• 2018

Steel-concrete composite structure is widely applied to bridge engineering due to their outstanding mechanical properties and economic benefit. This paper studied a new type of steel-concrete composite anchorage system for a self-anchored suspension bridge and focused on the mechanical behavior and force transferring mechanism. A model with a scale of 1/2.5 was prepared and tested in ten loading cases in the laboratory, and their detailed stress distributions were measured. Meanwhile, a three-dimensional finite element model was established to understand the stress distributions and validated against the experimental measurement data. From the results of this study, a complicated stress distribution of the steel anchorage box with low stress level was observed. In addition, no damage and cracking was observed at the concrete surrounding this steel box. It can be concluded that the composite effect between the concrete surrounding the steel anchorage box and this steel box can be successfully developed. Consequently, the steel-concrete composite anchorage system illustrated an excellent mechanical response and high reliability.

• Journal of the Korean Society of Costume
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• v.52 no.7
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• pp.71-85
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• 2002

The purpose of this study is (1) to research on the diverse evaluation criteria suggested in the existing literatures, selected the contents of the evaluation according to the evaluation factors, and examined whether they are appropriate for the evaluation of websites that offer Clothing and Ornament related information through reliability analysis - all to set the evaluation criteria for the websites that acquire data. In addition. (2) contents of evaluation which are deemed important by the users and developers were compared and recommended as the detailed evaluation contents according to evaluation factors. The results of this study were as follows. 1. The evaluation factors for the fashion websites that provide Clothing and Ornament related information were selected as follows: contents of the information(11 contents of evaluation), ease of use(12), screen design(10), accessibility(9), sensitive enjoyment(4), scope of information use(3), purpose(1), and target user(1). As result of reliability analysis. Cronbach's a contents of the information (0.76), ease of use (0.77), screen design (0.85), accessibility (0.81), sensitive enjoyment (0.71), and scope of information use (0.52). 2. When the level of importance for the detailed evaluation contents was examined from the user and developer point of view, recency of information. rapid speed for the websites access. fast loading of webtext and fast transmission speed topped the list as first, second and third places.

• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.1
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• pp.87-95
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• 1989

The fatigue crack propagation of random short fiber SMC composite material was investigated. In macroscopic viewpoint, SMC composite material was treated as isotropic material and was analyzed in terms of conventional fracture mechanics. Experiments were conducted on mode I and mixed respectively and various loading level was applied to each mode. Fatigue crack growth can be explained in three steps and most of fatigue life is consumed in initial crack growth. In this experiments, power law, i.e, da/dN=C(C.DELTA.K)$^{m}$ , between fatigue crack growth rate and stress intensity factor range, was valid and the value of the exponent m is about 10, which is much higher than that of other metals. Fracture mechanism was also investigated by SEM fractographic study.

• Journal of Embryo Transfer
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• v.28 no.1
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• pp.57-61
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• 2013

Microtubule-associated protein 1B (MAP1B), a member of MAP1 family, plays a key role in neuronal development. MAP1B binds to many kinds of proteins directly or indirectly. This study was performed to investigate whether MAP1B interacts with GAPDH in bovine follicles using immunoprecipitation (IP) with Western blot analysis and immunohistochemisty. The mRNA expressions of MAP1B and glyceraldehydes 3-phosphate dehydrogenase (GAPDH) were down-regulated in bovine follicular cystic follicles (FCF). In parallel with the mRNA levels, their protein levels were also down-regulated in FCFs. In addition, MAP1B and GAPDH were co-localized at the cytoplasm of follicles. IP with Western blot analysis showed that MAP1B bound to GAPDH in normal follicles, but their binding was absent in FCFs, suggesting a low level of MAP1B and/or GAPDH expressions in FCFs. Taken together, these results suggest that MAP1B interacted with GAPDH may play a role in bovine follicle development, and that GAPDH does not function always as a loading control in bovine follicles.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.562-562
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• 2014

Assessment of aerodynamic noise is becoming increasingly important for automotive manufacturers. Flow passing a vehicle may indeed lead to high interior noise level and affect cabin comfort. Interior noise results from various mechanisms including aerodynamic fluctuations of the disturbed flow around the side mirror or pillar, hydrodynamic and acoustic loading of the car panels and windows, vibration of these panels and acoustic radiation inside the vehicle. Objective of the present study is to capture these important mechanisms in a simulation model and demonstrate the ability of the combined simulation tools Fluent / Virtual.Lab to provide accurate aerodynamic and interior noise prediction results. Previous study focused on the noise generated by the turbulence around the A-pillar structure of the HSM (Hyundai simplified model). The present study also includes the effect of the side-mirror and rain-gutter structures. Complete modeling process is presented including details on the unsteady CFD simulation and the vibro-acoustic model with absorption materials. Guidelines and best practices for building the simulation model are also discussed.

• Journal of the Korean Society of School Health
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• v.22 no.2
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• pp.137-146
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• 2009

Purpose: This study was performed to identify the socioeconomic factors, the health behavior factors and dietary pattern that have an influence on abdominal obesity, as measured by using the waist circumference in children and adolescents. Methods: This study used data collected from 1998, 2001, 2005 Korean National Health and Nutrition Examination Survey (NHANES). Final sample included 3,596 subjects from 10 to 19 years old who had completed necessary health examinations, health behaviors survey, and nutrition survey. Results: 12 dietary patterns emerged from factor analysis with different factor loading. Logistic regression analysis of the factors that affect abdominal obesity showed that the education level, BMI(Body Mass Index) and dietary pattern, 'Kimchi' including Korean cabbage and radish affected the abdominal obesity in children and adolescents. Conclusions: Abdominal obesity is a risk factor for morbidity and mortality, and it is associated with chronic diseases, including cardiovascular disease and diabetes. Based on the findings, it is essential to modify dietary pattern for preventing abdominal obesity, which is a condition associated with the incidence of chronic disease in adults.

• Korean Journal of Materials Research
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• v.25 no.4
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• pp.183-190
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• 2015

Fatigue crack growth rate tests were conducted as a function of temperature, dissolved hydrogen (DH) level, and frequency in a simulated PWR environment. Fatigue crack growth rates increased slightly with increasing temperature in air. However, the fatigue crack growth rate did not change with increasing temperature in PWR water conditions. The DH levels did not affect the measured crack growth rate under the given test conditions. At $316^{\circ}C$, oxides were observed on the fatigue crack surface, where the size of the oxide particles was about $0.2{\mu}m$ at 5 ppb. Fatigue crack growth rate increased slightly with decreasing frequency within the frequency range of 0.1 Hz and 10 Hz in PWR water conditions; however, crack growth rate increased considerably at 0.01 Hz. The decrease of the fatigue crack growth rate in PWR water condition is attributed to crack closure resulting from the formation of oxides near the crack tips at a rather fast loading frequency of 10 Hz.

• Journal of the Korean Society of Industry Convergence
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• v.14 no.1
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• pp.29-36
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• 2011

This study analyzed the convenience and productivity before and after adopting self-propelled power transportation devices to the harvest and transportation of fruit and vegetable products in the Gyeongbuk region, by applying the REBA and RULA techniques. In the REBA analysis, the work risk was low with 4~6 points before adoption which became 2~3 points after adoption. As for the RULA analysis, work loading appeared to have decreased with 6~7 points before adoption which became 3~4 points after adoption. The annual work time reduction was about 48~179 hours while labor costs were reduced to 364~1,345 thousand won annually. This indicated a labor cost reduction effect of about 10~15%. Therefore, the adopted self-propelled power transportation devices appeared to prevent musculo skeletal diseases of the human body and also improve productivity even after using it for long hours according to the REBA, RULA measures level.

• The Korean Journal of Health Service Management
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• v.9 no.4
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• pp.1-12
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• 2015

Objectives : The aim of this research was to develop evaluation indicators that ensure safe services and enhance the quality of small-sized dental hospitals within local communities to prepare for the dental hospital accreditation system. Methods : Materials and data from a total of 460 respondents were analyzed after quality improvement indicators were formed by surveying experts and studying documents in Korea and abroad, and by conducting a survey from August 21, 2013 to September 30, 2013 for validation purposes. Results : Based on the results of factor analysis. all measured items appeared to be statistically significant with a factor loading score of at least 0.5, and the correlation between the factors all appeared to be high as well. The goodness-of-fit for the model also appeared to be within the recommended acceptance level. Thus, the proposed evaluation indicators for dental hospital accreditation developed in this study consisted of a total of seven major category factors and a total of 91 detailed items. Conclusions : Furthermore, the results suggest that the evaluation indicators can be used to improve the quality and to ensure the safe services of dental hospitals in local communities.

• International Journal of Aeronautical and Space Sciences
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• v.7 no.1
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• pp.137-147
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• 2006

In this study, shape memory alloy damper with characteristics of pseudoelastic hysteresis for helicopter rotor blades are investigated. SMAs can be available in damping augmentation of vibrating structures. SMAs show large hysteresis in the process of pseudoelastic austenite-martensite phase transformation which takes place while subjected to loading above the austenite finish temperature. Since SMAs display pseudoelastic hysteresis behavior over large strain ranges, a significant amount of energy dissipation is possible. A damper can be designed with SMA wires prestressed to a baseline level somewhere in the middle of the pseudoelastic stress range. An experimental study of the effects of pre-strain and cyclic strain amplitude as well as frequency on the damping behavior of pseudoelastic shape memory alloy wires are performed. The effects of the shape memory alloy damper on aeroelastic and ground resonance stability of helicopter are studied. In aeroelastic stability, the dynamic characteristics of blades related to pitch angle and the amplitude of lag motion for the rotor equipped with SMA damper were examined. The performance of SMA damper on ground resonance instability are presented through the frequencies and modal damping with respect to rotating speed.