• Earthquakes and Structures
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• 제11권4호
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• pp.609-627
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• 2016

Results of an experimental program are presented in this paper for the influence of vertical load on the in-plane behavior of masonry infilled steel frames. Five half-scaled single-story, single-bay steel frame specimens were tested under cyclic lateral loading. The specimens included four infilled frames and one bare frame. Two similar specimens as well as the bare frame had moment-resisting steel frames, while the remaining two specimens had pinned steel frames. For each frame type, one specimen was tested under simultaneous vertical and lateral loading, whereas the other was subjected only to lateral loading. The experimental results show that the vertical load changes the cracking patterns and failure modes of the infill panels. It improves dissipated hysteresis energy and equivalent viscous damping. Global responses of specimens, including stiffness and maximum strength, do no change by vertical loading considerably. Regarding the ductility, the presence of vertical load is ignorable in the specimen with moment-resisting frame. However, it increases the ductility of the infilled pinned frame specimen, leading to an enhancement in the m-factor by at least 2.5 times. In summary, it is concluded that the influence of the vertical load on the lateral response of infilled frames can be conservatively ignored.

• 대한치과의사협회지
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• 제54권6호
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• pp.438-446
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• 2016

Severe tooth wear may cause the pathologic change of the TMJ and masticatory muscles, unesthetic facial appearance, pathogenic pulp and occlusal disharmony. Treating patients with severely worn dentition often requires full mouth rehabilitation with increasing vertical dimension. Proper diagnosis and treatment planning are important for esthetic and functional definitive restorations and the long term stability of the neuromuscular system and the TMJ. In this case, 66 year-old female presented with generalized worn dentition. Based on assessment, pathologic destruction of teeth structure on entire dentition was caused by masticatory force and diet habit without loss of vertical dimension. Subsequently, 3 mm increase of vertical dimension that based on incisor for tooth restoration and esthetic improvement was determined. After 8 weeks stabilization period with temporary fixed prostheses, definitive prostheses were fabricated. After 6 months follow up period, satisfactory outcomes were attained both functional and esthetic aspects through this procedure.

• 한국공간구조학회논문집
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• 제17권4호
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• pp.51-58
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• 2017

The characteristics and effectiveness of double tuned mass dampers (DTMD) have been studied by many researchers. DTMD usually consists of one larger mass block and one smaller mass block. In this study, DTMD was proposed to reduce the vibration of vertical pumps in industrial plants. In order to assess the efficiency of the proposed method, numerical analysis for the simplified vertical pump model with single and double TMDs was carried out. It was also investigated that the effects of optimal TMD parameters such as frequency ratio and damping ratio on dynamic responses of the main structure. According to analysis results, DTMD are more effective to control the vibration of the vertical pump and show good robustness to the change in the stiffness of TMD.

• 연구논문집
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• 통권26호
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• pp.15-24
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• 1996

In this study, we performed the static analysis of a cord-reinforced rubber airspring and generated the three-dimensional half-symmetry model which use the finite-strain shell elements to model the airbag. the three-dimensional hydrostatic fluid elements to model the air-filled cavity, and the rebar elements to model the multi-ply nylon reinforcement of airbag. In addition, a three-dimensional rigid surface is used to define the contact between the airspring and metal bead. The air inside the airspring cavity has been modeled as a compressible fluid satisfying the ideal gas law. The conclusions of this study are as follows. 1) In the pressurization step of analysis, we could predict the change of vertical reaction force, cavity volume and pressure within the airspring. 2) In the second step of analyzing vertical static stiffness, the increase of the vertical load increases the vertical stiffness. 3) In case of changing the angle of nylon cord, the increase the angle of nylon cord increases the vertical stiffness.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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• pp.383-386
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• 2006

Subsurface temperature is affected by heat advection due to groundwater advection. Temperature-depth profile can be perturbed especially when there are significant vertical groundwater flux caused by external force such as injection or extraction. This research is to clarify the change of subsurface temperature distribution when the 40m x l0m sandy aquifer is stimulated by two different vertical flux($case1:\;{\pm}10^{-5}m^3/s,\;case2:\;{\pm}4{\times}10^{-5}m^3/s$) using a program called HydroGeoSphere. The resulting temperature distribution contour map shows pumping causes vertical attraction of water from deeper and warmer place which result in rising up isotherm. Additionally more injection/extraction rate, more vertical groundwater flux leads to faster Increase in temperature near the pumping well.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 1999년도 추계학술대회 논문집
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• pp.111-114
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• 1999

Off-vertical axis rotator was developed to differentiate each function of the canal and otolith in the vestibular system and evaluate subjective symptoms during postural change. Eye movement induced by various types of rotation was measured in normal subjects. Nystagmus with fast component corresponding to direction of rotation was occurred by sinusoidal earth vertical axis rotation, and the gain of eye movement in vestibuloocular reflex (VOR) was lower than in visual vestibuloocular reflex (VVOR) and higher than in visual fixed vestibuloocular reflex (VFX). Degree of dizziness was proportioned to degree of gain. off-vertical axis rotation was produced severe dizziness than earth vertical axis rotation. These results suggest stimulation of the otolith should be minimized to make a stable and pleasant condition in work and travel.

• International Journal of Oral Biology
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• 제46권4호
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• pp.208-213
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• 2021

Increasing the vertical dimesion affects not only functional problems but also the facial appearance. In particular, when restoring the reduced vertical dimension, it is important to evaluate facial appearance because the change affects the patient's aesthetics. Cephalometric radiographs can predict changes in the facial appearance through skeletal and vertical classifications using anatomical indicators, and the changes before and after treatment can be easily observed, which could serve as good data in evaluating treatment success. In this study, comparative evaluation was performed through cephalometric radiography, and the aesthetic and functional improvement was confirmed.

• Structural Engineering and Mechanics
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• 제59권4호
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• pp.719-737
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• 2016

The present study investigated the earthquake behavior of R/C structures considering the vertical earthquake motion with the help of a comparative study. For this aim, the linear time-history analyses of a high-rise R/C structure designed according to TSC-2007 requirements were conducted including and excluding the vertical earthquake motion. Earthquake records used in the analyses were selected based on the ratio of vertical peak acceleration to horizontal peak acceleration (V/H). The frequency-domain analyses of the earthquake records were also performed to compare the dominant frequency of the records with that of the structure. Based on the results obtained from the time-history analyses under the earthquake loading with (H+V) and without the vertical earthquake motion (H), the value of the overturning moment and the top-story vertical displacement were found to relatively increase when considering the vertical earthquake motion. The base shear force was also affected by this motion; however, its increase was lower compared to the overturning moment and the top-story vertical displacement. The other two parameters, the top-story lateral displacement and the top-story rotation angle, barely changed under H and H+V loading cases. Modal damping ratios and their variations in horizontal and vertical directions were also estimated using response acceleration records. No significant change in the horizontal damping ratio was observed whereas the vertical modal damping ratio noticeably increased under H+V loading. The results obtained from this study indicate that the desired structural earthquake performance cannot be provided under H+V loading due to the excessive increase in the overturning moment, and that the vertical damping ratio should be estimated considering the vertical earthquake motion.

• 한국환경과학회지
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• 제16권9호
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• pp.1051-1061
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• 2007

The impact of midlatitude synoptic system (upper-level trough) on typhoon intensity change was investigated by analyzing the spatial and temporal characteristics of vertical wind shear (VWS), relative eddy momentum flux convergence (REFC), and potential vorticity (PV). These variables were computed over the radial mean $300{\sim}1,000km$ from the typhoon center by using GDAPS (Global Data Assimilation and Prediction System) data provided by the Korea Meteorological Administration (KMA). The selected cases in this study are typhoons Rusa (0215) and Maemi (0314), causing much damage in life and property in Korea. Results show that the threshold value of VWS indicating typhoon intensity change (typhoon to severe tropical storm) is approximately 15 m/s and of REFC ranges 6 to 6.5 $ms^{-1}day^{-1}$ in both cases, respectively. During the period with the intensity of typhoon class, PVs with 3 to 3.5 PVU are present in 360K surface-PV field in the cases. In addition, there is a time-lag of 24 hours between central pressure of typhoon and minimum value of VWS, meaning that the midlatitude upper-level trough interacts with the edge of typhoon with a horizontal distance less than 2,000 km between trough and typhoon. That is, strong midlatitude upper-level divergence above the edge of the typhoon provides a good condition for strengthening the vertical circulation associated with the typhoons. In particular, when the distance between typhoon and midlatitude upper-level trough is less than 1,000 km, the typhoons tend to weaken to STS (Severe Tropical Storm). It might be mentioned that midlatitude synoptic system affects the intensity change of typhoons Rusa (0215) and Maemi (0314) while they moves northward. Thus, these variables are useful for diagnosing the intensity change of typhoon approaching to the Korean peninsula.

• Journal of Periodontal and Implant Science
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• 제34권3호
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• pp.509-522
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• 2004

This study was performed to compare the clinical effectiveness of two regenerative techniques for class II furcation involvements in human: a combination of bone grafts with PRP vs. GTR with bone grafts. The e-PTFE group was treated with non-absorbable membrane and bone grafts, the PRP group was treated with PRP and bone grafts Pocket depth, clinical attachment level, and gingival recession were measured at baseline and postoperative 6 months. Vertical and horizontal furcation depth were measured by re-entry surgeries at 6 months post-treatment Both groups were statistically analyzed by Wilcoxon signed Ranks Test & Mann-whitney Test using SPSS program (5% significance level). The results were as follows: 1. The change of pocket depth, clinical attachment level, vertical furcation depth and horizontal furcation depth in both groups was decreased significantly at 6 months than at baseline. (p<0.05) 2. The change of gingival recession in both groups was increased significantly at 6 months than at baseline. (p<0.05) 3. The change of alveolar crest absorption in both groups was increased at 6 months than at baseline but there were no statistically significant differences. 4. The change of pocket depth, clinical attachment level, vertical furcation depth and horizontal furcation depth in both groups was increased significantly at 6 months, but there were no statistically or clinically significant differences with both groups. 5. The change of gingival recession and alveolar crest absorption in both groups was increased at 6 months, but there were no statistically or clinically significant differences with both groups. In conclusion, the use of bone graft with PRP or GTR technique improved clinical index of the soft and hard tissue in mandibular class II furcation involvement but there were no statistically or clinically significant differences between bone graft with PRP and GTR technique.