• Journal of Coastal Disaster Prevention
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• v.4 no.3
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• pp.111-118
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• 2017

In this study, pull box members were designed by finite element analysis of a steel plate covering a pull box to secure its safety on the landing pier dedicated to the large research survey ship. It was assumed that the maximum load is due to the 250 tonf class crane used for unloading work when the working environment in the upper part of the landing pier was considered. The safety of the pull box was evaluated by the comparison between the yield strength of the steel plate and the result of stress analysis on the steel plate due to the crane load. It was found that the stress at the plate from the crane load exceeded the yield strength of the steel(205MPa) when the upper part of the pull box was protected by a $1950{\times}1950mm$ steel plate cover. In order to compensate for this, a concrete filled steel tube(CFT) column with a diameter of 150 mm and a steel thickness of 10 mm was reinforced at the center of the plate, and the finite element analysis was carried out. However, the maximum stress at the steel plate was higher than the yield strength of the steel in some load cases so that it was tried to find appropriate thickness of the steel plate and diameter of the CFT columns. Finally, the analysis results showed that the safety of the pull box was secured when the thickness of the steel plate and the diameter of the CFT column were increased to 30mm and 180mm, respectively.

• Steel and Composite Structures
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• v.44 no.4
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• pp.503-517
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• 2022

This paper presents the mechanical buckling of bi-directional functionally graded sandwich beams (BFGSW) with various boundary conditions employing a quasi-3D beam theory, including an integral term in the displacement field, which reduces the number of unknowns and governing equations. The beams are composed of three layers. The core is made from two constituents and varies across the thickness; however, the covering layers of the beams are made of bidirectional functionally graded material (BFGSW) and vary smoothly along the beam length and thickness directions. The power gradation model is considered to estimate the variation of material properties. The used formulation reflects the transverse shear effect and uses only three variables without including the correction factor used in the first shear deformation theory (FSDT) proposed by Timoshenko. The principle of virtual forces is used to obtain stability equations. Moreover, the impacts of the control of the power-law index, layer thickness ratio, length-to-depth ratio, and boundary conditions on buckling response are demonstrated. Our contribution in the present work is applying an analytical solution to investigate the stability behavior of bidirectional FG sandwich beams under various boundary conditions.

• Archives of Plastic Surgery
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• v.40 no.3
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• pp.209-213
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• 2013

Background A cartilage wedge block and covering flap are standard procedures for firm elevation of the ear in microtia correction. However, using costal cartilage for elevation of the reconstructed auricle can be insufficient, and the fixed cartilage wedge block may be absorbed or may slip out. Furthermore, elevating covering flaps is time-consuming and uses up fascia, a potential source of reconstruction material. Therefore, we propose an innovative method using autologous onlay rib bone graft for auricular elevation of microtia. Methods From February 1995 to August 2012, 77 patients received a first stage operation with a rib cartilage framework graft. In the second stage operation, a small full thickness of rib bone was harvested through the previous donor scar. The bihalved rib bone was inserted into the subperiosteal pocket beneath the cartilage framework. Results The follow-up time ranged from 1 month to 17 years, with a mean of 3 years. All of the patients sustained the elevation of their ears very well during the follow-up period. Donor site problems, except for hypertrophic scars, were not observed. Surgery-related complications, specifically skin necrosis, infection, or hematoma, occurred in 4 cases. Conclusions Onlay rib bone graft used to elevate the reconstructed auricle is a more anatomically appropriate material than cartilage, due to the bone-to-bone contact between the bone graft and the temporal bone. Postoperative minor correction of the elevation degree is straightforward and the skin graft survives better. Therefore, reconstructed auricle elevation using onlay rib bone graft is a useful and valuable method.

• The Journal of the Acoustical Society of Korea
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• v.40 no.6
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• pp.587-592
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• 2021

Change in the cortical thickness of long bones occurring with aging and osteoporosis is known to be a risk factor for fracture. The present study aims to investigate the dependencies of phase velocities of ultrasonic guided waves on the cortical thickness in 7 soft tissue-bone mimicking phantoms consisting of acrylic plates covered by a 2 mm-thick silicone rubber layer by using the axial transmission technique with a pair of transducers with a center frequency of 200 kHz and a diameter of 12.7 mm. Two distinct propagating waves with different velocities, the First Arriving Signal (FAS) and the Slow Guided Waved (SGW), were consistently observed for all the soft tissue-bone mimicking phantoms. The FAS velocity decreased slightly with increasing thickness, whereas the SGW velocity increased strongly with increasing thickness. The FAS and the SGW velocities were found to be closely consistent with the S0 and the A0 Lamb mode velocities for a free acrylic plate, respectively, suggesting that the presence of the soft tissue mimicking material (2 mm-thick silicone rubber layer) covering the acrylic plates does not influence significantly the velocity measurements.

• Current Research on Agriculture and Life Sciences
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• v.33 no.2
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• pp.41-47
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• 2015

This study calculated the overall heat transfer coefficient (U-value) of greenhouse covering materials with thermal screens using a simulation model and then estimated the validity of the calculated results by comparison with measured values. The U-value decreased gradually as the thickness of the air space between the double glazing increased, and then remained essentially constant at thicknesses exceeding 25 mm. The U-value also increased with the difference in temperature between the inside and outside of the hot box. The vigorous convective heat transfer between two plastic films caused unsteady heat flow and then created a nonlinear temperature distribution in the air space. The distance did not affect the U-value at distances of 50~200 mm between the plastic covering and thermal curtain. The numerical calculation results, with and without sky radiation, were in accord with the experimental results for a $30^{\circ}C$ temperature difference between the inside and outside of the hot box. In conclusion, a reliable U-value can be calculated for a temperature difference of $30^{\circ}C$ or more between the inside and outside of the hot box.

• Fire Science and Engineering
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• v.26 no.6
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• pp.72-77
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• 2012

When the concrete and steel combined composite beam is exposed to high temperature, concrete could delay temperature rising of steel by covering or increase heat capacity of structural member. For becoming of structural reinforcing by unification between materials, fire resistance rate of composite beam would be higher than simple steel beam. The temperature rising of exposed steel of composite beam is directly related with section shape and exposure length of steel. In this study, fire resistant tests were carried out for composite beams and steel beam with same thickness of spray-type fire resistant materials in standard fire, and after that, temperature histories were analysed and compared with shape factor. The correlation between steel temperature and shape factor was showed very high. This result suggests that if it can be predict the comparative advantage of member by factor which cause the performance enhancement, it could be conclude that an Standard Accreditation method can be adjust to members without indivisual certifiicate of accreditation.

• The korean journal of orthodontics
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• v.13 no.2
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• pp.177-183
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• 1983

The soft tissue covering of the face plays an important role in facial esthetics, speech and other physiologic functions. Thus, it is recognised by all clinical orthodontists that success of orthodontic treatment is closely related to the changes in soft tissues of the face. The purpose of this study was to evaluate the changes of bony and soft tissues in prepost treatment of Angle's Class III malocclusion. The sample consisted of 18 males and 37 females, pretreatment age of 9 years to 11 years. For this study 11 landmarks were plotted, 14 linear length, 4 soft tissue thickness and 2 angles were measured. The obtained results were as follows; 1. In the linear measurements of bony and soft tissue changes, A, Is, Ss, Ls and Li were located more anteriorly in both sexes. However Si and B showed more remarkable anterior movement in female. 2. In the comparison of the changes of the soft tissue thickness, Ss and Li in male subjects and Ss in female subjects increased. 3. In the degree of correlation between changes in the soft tissue profile and changes in the skeletal profile, Is: Ls, Il: Li and B: Si in both sexes had significant correlations. However A:Ss had remarkable significant correlation in female. 4. There were significant correlations between change in ${\angle}A$ and change in ${\angle}B$ in all sexes. 5. There were little correlation between changes in distance difference of Is and Ii and Change in distance difference of Ls and Li in all sexes.

• Fashion & Textile Research Journal
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• v.20 no.2
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• pp.219-225
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• 2018

The purpose of this study is to make an ideal dummy for adult Maltese with proper investigation of its character and direct measurement of dog body-shape. The results of the study are as follows; First, there were 6 factors to affect the characteristics of Maltese body in the analysis, which are size of body, leg shape, chest shape, leg thickness, body length, length between fore-legs. In the cluster analysis with the 6 factors there were two types of Maltese body. Type 1 has body characteristics with large body, thick leg, and small distance between front legs. Type 2 has average size of all factors including body size, leg thickness, and length between fore-legs. Second, type 2 was selected as a representative one to make a dummy reflected body shape of characteristics because it took 67.71% from entire considered factors and has average value in the measured size. The first dummy pattern was planned by copying the surface area of the representative body shape with the method of surgical tape. A dummy of single body with trunk and legs was made using 30's cotton cloth, polyester inside batting, compressed form PVC and metallic wire on the joint of trunk and legs to support dummy shape. The second pattern was made by correcting size difference of the pattern and adding the pattern of neck covering plate, metal magnetic button was inserted on the center of joint area of trunk and legs to make detachable legs for easy slip on and off the pet's wear.

• Steel and Composite Structures
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• v.23 no.3
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• pp.273-283
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• 2017

In this paper, it is aimed to present a detail investigation related to structural behavior of laterally unrestrained steel cantilever roof of tribune with slender cross section. The structure is located in Tutak town in $A{\breve{g}}r{{\i}}$ and collapsed on October 25, 2015 at eastern part of Turkey is considered as a case study. This mild sloped roof structure was built from a variable I beam, and supported on steel columns of 5.5 m height covering totally $240m^2$ closed area in plan. The roof of tribune collapsed completely without any indication during first snowfall after construction at midnight a winter day, fortunately before the opening hours. The meteorological records and observations of local persons are combined together to estimate the intensity of snow load in the region and it is compared with the code specified values. Also, the wide/thickness and height/thickness ratios for flange and web are evaluated according to the design codes. Three dimensional finite element model of the existing steel tribune roof is generated considering project drawings and site investigations using commercially available software ANSYS. The displacements, principal stresses and strains along to the cantilever length and column height are given as contour diagrams and graph format. In addition to site investigation, the numerical and analytical works conducted in this study indicate that the unequivocal reasons of the collapse are overloading action of snow load intensity, some mistakes made in the design of steel cantilever beams, insufficient strength and rigidity of the main structural elements, and construction workmanship errors.

• Imaging Science in Dentistry
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• v.46 no.3
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• pp.173-178
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• 2016

Purpose: Optical coherence tomography (OCT) has been investigated as a novel diagnostic imaging tool. The utilisation of this equipment has been evaluated through several studies in the field of dentistry. The aim of this preliminary study was to determine through basic experiments the effectiveness of OCT in implant dentistry. Materials and Methods: To assess detection ability, we captured OCT images of implants in each of the following situations: (1) implants covered with mucosae of various thicknesses that were harvested from the mandibles of pigs; (2) implants installed in the mandibles of pigs; and (3) implants with abutments and crowns fixed with temporary cement. The OCT images were captured before cementation, after cementation, and after removing the excess submucosal cement. Results: If the thickness of the mucosa covering the implant body was less than 1 mm, the images of the implants were clearly detected by OCT. In the implants were installed in pigs' mandibles, it was difficult to capture clear images of the implant and alveolar bone in most of the samples. Remnants of excess cement around the implants were visible in most samples that had a mucosa thickness of less than 3 mm. Conclusion: Currently, OCT imaging of implants is limited. Cement remnants at the submucosal area can be detected in some cases, which can be helpful in preventing peri-implant diseases. Still, though there are some restrictions to its application, OCT could have potential as an effective diagnostic instrument in the field of implant dentistry as well.