• Journal of the Korean Society for Marine Environment & Energy
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• v.14 no.4
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• pp.264-272
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• 2011

Shipbuilders carry out the operation test to check the conditions of the main propulsion system and auxiliaries for moored vessel in the quoy before the sea trial. The estimation of the thrust and torque for the partially submerged propeller should be prepared to ensure the safety of mooring line and the ship. In this paper, the variations of the thrust and torque according to the shaft submergence and the propeller rotating speed in bollard pull condition are investigated with the model test and the numerical analysis. Based on these resaearch, the empirical formula representing the physical phenomena of the partially submerged propeller is derived and validated through comparison to measurement results of full-scale propellers under the quoy operation test.

• Journal of the Korea institute for structural maintenance and inspection
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• v.9 no.1
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• pp.233-241
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• 2005

The paper is presented experimental study results on bond stress between profiled steel and concrete in Profiled SPC(Profiled Steel Plate Concrete) rectangular steel tubes through an experimental program in which 13 pull-out specimens were tested. Advantages and class of composite members and current problems of construction work are noted, past research of PSSC is described. An experimental study is described and evaluated. The bond capacity is interrelated with slip at the steel concrete interface. The factors influencing the mechanism of bond stress transfer were the cross section shape, length/diameter, diameter/thickness and environmental parameters (temperature, moisture). The results of experimental program indicated that the force transfer could be characterized into two regions The first region was governed by bond with no relative slip between the profiled steel and concrete. The second region occurs after the chemical debonding. Bond stress transfer in this region was governed by frictional resistance between profiled steel and concrete and cross section shapes. The important factors influencing the magnitude of frictional resistance are the profiled steel shapes, length/diameter and environmental parameters. (temperature, moisture)

• Journal of Life Science
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• v.28 no.2
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• pp.170-175
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• 2018

Parkinson's disease (PD) is the most common movement disorder and the second most common neurodegenerative disease after Alzheimer's disease. Approximately 5~10% of PD patients are familial PD cases. Leucine-rich repeat kinase 2 (LRRK2) has been known to be a causal gene of PD when it is mutated. LRRK2 contains the functional kinase and GTPase domains as well as leucine-rich repeat (LRR) and WD40 domains that are known to play critical roles for protein-protein interaction, suggesting that LRRK2-interacting proteins are important regulators for PD pathogenesis. In an effort to identify proteins interacting with LRRK2, we carried out co-immunoprecipitation of LRRK2 antibody using extracts of NIH3T3 cells that express LRRK2 at a relatively high level. The mass spectrometry analysis of a precipitated band revealed that the co-precipitated band was methionyl-tRNA synthetase (MRS), an ancient enzyme that transfers methionin to its cognate tRNA. The interaction of MRS with LRRK2 was confirmed again by co-immunoprecipitation of endogenous proteins and GST pull-down assays. However, LRRK2 did not phosphorylate recombinant MRS protein in in vitro kinase assays, and over-expression of LRRK2 or MRS did not affect the stability of its partner protein. Our data indicate that LRRK2 interacts with but does not phosphorylate MRS, and the stability of each partner is not affected by the other.

• Korean Journal of Food Science and Technology
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• v.52 no.4
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• pp.385-395
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• 2020

This study examined the effect of 3,4-dihydroxytoluene (DHT) on UVB-induced photoaging and determined its molecular mechanisms, using HaCaT human keratinocytes and SKH-1 hairless mice. DHT suppressed UVB-induced matrix metalloproteinase-1 (MMP-1) expression in HaCaT cells. In vivo data from mouse skin supported that DHT decreased UVB-induced wrinkle formation, epidermal thickness, and matrix metalloproteinase-13 (MMP-13) expression. DHT appeared to exert its anti-aging effects by suppressing UVB-induced Raf-1 kinase activity and subsequent attenuation of UVB-induced phosphorylation of MEK, ERK, and p90RSK in HaCaT cells. In vitro and in vivo pull-down assays revealed that DHT bound with Raf-1 in ATP-noncompetitive manner. Overall, DHT appears to anti-photoaging effects in vitro and in vivo through the suppression of Raf-1 kinase activity and may have potential as a treatment for the prevention of skin aging.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.928-930
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• 2000

교류전력을 측정하기 위하여 알고 있는 직류전력과 동시에 비교할 수 있는 전력비교기를 개발하였으며 이 비교기를 기본으로 하여 정밀 전력계와 전자식 전력량계를 교정하거나 시험검사 할 수 있는 기준시스템인 전력표준기를 개발하였다. 특히 Push-Pull 기술을 이용한 전력비교기는 간단하며 정확도가 매우 높은 것으로 평가되었으며 전력비교기의 전체 불확도는 30 $\mu$ W/VA로 평가되었다.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.9_10 s.157
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• pp.1455-1463
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• 2006

The purpose of this study was to examine the advertisement effects of mobile fashion advertisements, specifically focusing on how the mobile fashion advertisement effects work according to advertisement types and categories. Two hundred female college students participated in this study. For data analysis, descriptive statistics, factor analysis, and t-test were used for this study. As the results, first, advertisement attitudes were classed into three factors such as cognitive factor emotional factor, and behavioral factor. Second, regarding the effect of advertisement types, pull advertisement type had higher advertisement attitudes, and higher purchasing intention than push advertisement type. There was not significant in brand attitudes between pull advertisement and push advertisement. Third, for the effects of advertisement categories, clothing advertisement had higher cognitive factor and behavioral factor, and higher purchasing intention than accessory advertisement. There were not significant in emotional factor and brand attitude between clothing and accessory advertisements. Based on these results, M-commerce fashion advertisement marketing strategies would be suggested.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1371-1375
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• 2005

The paper has analyzed the influence of tire design variable on the tire Force and Moment (F&M) characteristics, especially by the belt angle, the Plysteer Residual Aligning Torque (PRAT) which is considered as one of the causing factors for the vehicle pull. To validate the tire FE model, the tire stiffness and the PRAT which can be derived from the simulation data have been compared with the experimental data of test machine. In addition to PRAT characteristic, the tire stiffness and cornering characteristics due to the belt angle have been investigated. The effects of drum's curvature on the PRAT have been also investigated using the tire FE model and the usefulness of the current drum type F&M test machine can be confirmed.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.9
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• pp.903-912
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• 2009

This study is focused on simulation-based dimensional tolerance optimization process (DTOP) to minimize vehicle pulls by reduction of dimensional variation in front suspension system. In previous studies, the effect of tires and wheel alignment sensitivity have mainly been investigated to eliminate vehicle pulls in nominal design condition without allocating optimal tolerance level for selected components, among various factors regarding vehicle pulls such as vehicle design parameters, vehicle weight balance, tires, and environmental factors. Unfortunately, there are wide variations in the real vehicle, and these have impacted actual vehicle pulls, especially wheel alignment effects from suspension geometry variation has not been considered in the previous studies. In the tolerance design of suspension, tolerance variables with the uncertainty such as parts dimensional variation, assembly process, datum position and direction, and assembly tool tolerance has a great influence on the variation of the suspension dimensional performances. This study introduces total vehicle pull prediction model in considering major key factors for vehicle pull sensitivity. The Monte Carlo-based tolerance analysis model using Taguchi robust method is developed to optimize dimensional tolerance parameters, satisfying on the target variation level.

• Journal of Korean Neurosurgical Society
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• v.62 no.5
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• pp.577-585
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• 2019

Objective : Comparing the effects of magnetically controlled growing rod (MCGR) and traditional growing rod (TGR) techniques on the sagittal plane in the treatment of early-onset scoliosis (EOS). Methods : Twelve patients were operated using dual MCGR technique in one center, while 15 patients were operated using dual TGR technique for EOS in another center. Patients' demographic characteristics, complications and radiological measurements such as cobb angle, thoracic kyphosis, lumbar lordosis, T1-S1 range (mm), proximal junctional angle, distal junctional angle, sagittal balance, coronal balance, pelvic incidence, sacral slope and pelvic tilt were assessed and compared in preoperative, postoperative and last follow-up period. Results : Age and sex distributions were similar in both groups. The mean number of lengthening in the MCGR group was 12 (8-15) and 4.8 (3-7) in the TGR group. Two techniques were shown to be effective in controlling the curvature and in the increase of T1-S1 distance. In TGR group, four patients had rod fractures, six patients had screw pull-out and four patients had an infection, whereas three patients had screw pull-out and one patient had infection complications in the MCGR group. Conclusion : There was no significant difference between the two groups in terms of cobb angle, coronal and sagittal balance and sagittal pelvic parameters. MCGR can cause hypokyphosis and proximal junctional kyphosis in a minimum 2-year follow-up period. The implant-related complications were less in the MCGR group. However, larger case groups and longer follow-up periods are required for the better understanding of the superiority of one method on other in terms of complications.

• Journal of the Society of Disaster Information
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• v.19 no.2
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• pp.262-269
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• 2023

Purpose: In this study,fire-resistance test were executed to evaluate the effectiveness of the fireproof panel attached to the PSC slab in tunnel. Method: For the fire resistance test, the RWS curve was applied and the furnace of the KICT was used. Result: As a result of the experiment, the maximum temperature measured on the concrete surface of the PSC slab with the fireproof panel was 321.8℃, which was lower than the damage limit temperature of 380℃ for concrete. Also, at the t=25mm, the maximum temperature was 35.2℃, which was lower than the damage temperature of steel, 250℃. The use of precast fire resistance panel(t=30mm) improves fire resistance of PSC structures. Conclusion: As a result of the test, a reinforcement method for attached a fireproof panel in case of fire in a tunnel or an underground roadway is provided to protect a structure from fire. In the future, it is necessary to perform the static performance test of the slab to which the fireproof panel is attached, and to confirm the adhesion performance of the fireproof panel by performing the pull-off test and the fatigue test.