• Korean Journal of Construction Engineering and Management
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• v.11 no.6
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• pp.111-121
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• 2010

As the customer's interest for sidewalk block in the street or apartment complex is increasing, the materials of block which had been a concrete block exclusively are varied to clay paver, native rock and wood etc. Especially, the sales volume of clay paver which is environment-friendly and ergonomic is dramatically increasing every year with two digits growth rate, however, many problems like "Edge Cracking" "Freezing Breakage" "Bending Breakage" "Joint Gap" are happening frequently within a couple of hours after installation due to the durabilities. Because of the characteristics of Ceramic products, clay pavers are very easy to be broken when they are bumped against each other. In addition, they are relatively fragile by a freezing expansion breakage when exposed to water due to hydrophilic property as well as the intensity and absorptance of the products are varied with small difference from the production process such as production equipment and process control. Therefore, it costs a lot of money to repair the breakdown unless production and installation is carried out according to the strict criteria of the quality control. In this study, the symptoms of breakdown frequently happened in clay paver are classified by each type and finally the solution for this problem in the production of brick, installation and criteria of quality control through compressive strength and absorptance test is suggested.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.4
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• pp.23-32
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• 2023

The seismic performance of buried PE pipes is reported to be favorable due to their exceptional elongation capacity at break. Although a seismic performance evaluation procedure based on the response displacement method has been summarized in Korea for fusion-bonded PE pipes, there is currently no procedure available for mechanically jointed PE pipes. This article aims to present a seismic performance evaluation procedure based on the response displacement method specifically designed for mechanically jointed PE pipes in Korea. When employing the mechanical joining method for PE pipes, it is recommended to adhere to the evaluation procedure established for segment-type pipes. This involves assessing the stress induced by the pipe, the expansion and contraction strain of the joint, and the bending angle of the pipe joint. Furthermore, the coefficient of inhomogeneity of the soil, which is necessary for estimating the axial strain of the ground, is introduced. Additionally, a computation method for determining lateral displacement and reconsolidation settlement in soil susceptible to liquefaction is proposed. As a result of the sensitivity analysis considering the typical soil condition in Korea, the mechanically jointed PE pipe with a certain quality was shown to have good structural seismic safety when soil liquefaction was not considered. This procedure serves as a valuable tool for seismic design and evaluating the seismic performance of mechanically joined buried PE pipes, which are primarily utilized for connecting small-diameter pipes.

• Journal of Korean Neurosurgical Society
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• v.57 no.4
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• pp.276-282
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• 2015

Objective : The purpose of this study was to investigate morphological change at the craniovertebral junction (CVJ) region using computed tomography. Methods : A total of 238 patients were included in this study, and mean age was $47.8{\pm}21.3months$. Spinal canal diameter, Power's ratio, McRae line, antero-posterior C1 ring height, atlantoaxial joint space, C2 growth, epidural space from the dens (M-PB-C2) and longitudinal distance (basion to C2 lower margin, B-C2) were measured. The mean value of each parameter was assessed for individual age groups. The cohorts were then divided into three larger age groups : infancy (I) (${\leq}2years$), very early (VE) childhood (2-5 years) and early (E) childhood ($5{\geq}years$). Results : Spinal canal diameter increased with age; however, this value did not increase with statistical significance after VE age. A significant age-related difference was found for all C2 body and odontoid parameters (p<0.05). Mean McRae line was 8.5, 8, and 7.5 mm in the I, VE, and E groups, respectively. The M-PB-C2 line showed up-and-down dynamic change during early pediatric periods. Conclusion : Expansion of the spinal canal was restricted to the very early childhood period (less than 5 years) in the CVJ region; however, the C2 body and odontoid process increased continuously with age. The above results induced a dynamic change in the M-PB-C2 line. Although C2 longitudinal growth continued with age, the McRae line showed relatively little change.

• International journal of advanced smart convergence
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• v.8 no.4
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• pp.121-129
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• 2019

We are based on the results of this study, the policy measures for improving the efficiency of supply & demand policy of public cremation facilities in six metropolitan cities in the whole nation could be suggested as follows. First, when the utilization rate of public cremation facilities by citizents out of the jurisdiction area was lower, the overall demand for cremation was high. Therefore, the supply & demand policy of public cremation facilities should be carried forward by preferentially focusing on Busan Metropolitan City(4.1%) and Daegu Metropolitan City(17.9%) with low utilization rate by citizens out of the jurisdiction area. Second, the utilization variance of public cremation facilities in the whole six metropolitan cities in the whole nation, was insignificant(1.4%). Therefore, for the efficiency of supply & demand policy of cremation facilities in those six metropolitan cities, the customized-policies considering the characteristics of each metropolitan city should be carried forward in priority. Third, on the basis of 2018, the population size of those six metropolitan cities in the whole nation is from minimum 1.15million to maximum 3.39million as a large city, and relatively, they are facing many difficulties in the expansion for supply & demand of cremation facilities. Therefore, for the smooth construction of cremation facilities, it would be necessary to enforce policies that could disperse the demand for cremation through the joint construction of cremation facilities with other local governments close to each metropolitan city.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.5
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• pp.74-82
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• 2017

Localized corrosions damages in their structural sections can be occurred affected by installed environment conditions with high temperature as near the coastline and humidity or their poor maintenance situation. In bearing supports of steel bridges, especially, lower web and vertical stiffener in end girder support can be easily corroded because of relatively higher humidity due to the narrow space in the end of girder and the wetted accumulated sediments affected by rain water or antifreezing admixture leaked from expansion joint. It can be related to change in their structural performance. In this study, thus, bearing strength test specimens were fabricated considering corrosion damage in the web and vertical stiffeners and the change in their bearing strengths were experimentally evaluated. From the test results, localized corrosion damage of structural members in the end girder affected the bearing strength of end girder support, especially, localized corrosion damage of the vertical stiffener relatively highly affected their bearing strengths.

• Journal of Korea Port Economic Association
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• v.20 no.2
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• pp.169-185
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• 2004

It is an urgent problem that Korea logistics enteprises' expansion of advance into China market and the logistics network establishment between Korea and China to back up the former are to be solved. Accordingly, the purpose of this study is to deduce the subjects to establish the logistics network between Korea and China, and to evaluate the priority order. The results of this research are as follows: First, we conducted face-to-face interviews on the advisery group in China and Korean enterprises which advanced into China, and drew out 6 promoting subjects to build the logistics network between the two. Second, the AHP model was adopted, which is a multi-criteria?multi-hierarchical decision making method, to draw out the weight and priority order of the deduced 6 promoting items. Third, the resultant priority order of the promoting subjects is as follows: No.1 - to establish the distribution & logistics support center by region(0.3900); No.2 - to support various taxes in investing the logistics business abroad(0.1980) ; No.3 - to improve the management of CIQ(0.1958); No.4 - to back up the joint-venture of logistics firms(0.1169); No.5 - to enhance trade and foreign policies to deregulate the entry into logistics markets(0.0536); No.6 - to construct the logistics information system of China(Northest Ssia)(0.0458). This paper resulted in finding out Korea logistics enterprises that have not secured their own inland-transport network in China and the actual difficulties of Korean enterprises with using the inferior network that advanced into China. These problems were developed into the analysis adopting the AHP method, and the significancy of this paper is to present the priority order of promoting problems using a sophisticated technique.

• The Journal of the Korean bone and joint tumor society
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• v.20 no.1
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• pp.22-26
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• 2014

An intraosseous epidermal cyst is a rare benign cystic lesion. It is thought to result from congenital factors or trauma and can lead to bone destruction because the cyst develops at the soft tissue around the bone. Radiological findings of intraosseous epidermal cysts are a well-defined radiolucent lesion, with cortical expansion. It is important to differentiate an intraosseous epidermal cyst with other disease developed at distal phalanx because its clinical and radiological findings are similar. We report two rare cases of intraosseous epidermal cysts that developed at the distal phalanx.

• Smart Structures and Systems
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• v.6 no.4
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• pp.373-388
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• 2010

The updated finite element model of K$\ddot{o}$m$\ddot{u}$rhan Highway Bridge on the Firat River located on the $51^{st}$ km of Elazi$\breve{g}$-Malatya highway is obtained by using analytical and experimental results. The 2D and 3D finite element model of the bridge is created by using SAP2000 structural analyses software, and the dynamic characteristics of the bridge are determined analytically. The experimental measurements are carried out by Operational Modal Analysis Method under traffic induced vibrations and the dynamic characteristics are obtained experimentally. The vibration data are gathered from the both box girder and the deck of the bridge, separately. Due to the expansion joint in the middle of the bridge, special measurement points are selected when experimental test setups constitute. Measurement duration, frequency span and effective mode number are determined by considering similar studies in literature. The Peak Picking method in the frequency domain is used in the modal identification. At the end of the study, analytical and experimental dynamic characteristic are compared with each other and the finite element model of the bridge is updated by changing some uncertain parameters such as material properties and boundary conditions. Maximum differences between the natural frequencies are reduced from 10% to 2%, and a good agreement is found between natural frequencies and mode shapes after model updating.

• Journal of Korea Technology Innovation Society
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• v.9 no.1
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• pp.175-198
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• 2006

Analyzing the effects of information technology(IT) in the life insurance Industry is important in establishing the direction for future information technology investment. In this research, the cost-elasticity of IT capital stock was measured by the SUR technique, using the second-order translog cost function, which was drawn out by a Taylor expansion of the multi-product joint cost function. Analysis was made based on data from 1991 to 2003 collected from 33 life insurance firms. The results show that although the effects of information technology investment vary according to individual life insurance firms, half of the life insurance firms surveyed reduced their costs by investing in information technology. The research also revealed that although large life insurance firms reduced their costs by investing in information technology medium & small life insurance firms and foreign ,life insurance firms increase their costs. Additionally, although both information capital and information labor increase as the information budget increases, the increase in information capital is larger than one in information labor. Because the price of information capital is decreased rapidly more than one of information-related labor.

• The Journal of the Korea Contents Association
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• v.20 no.9
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• pp.249-260
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• 2020

This research examined Israel's economic trends, trades, and cooperation with Korea prior to the entry into force of the Free Trade Agreement (FTA) between Korea and Israel. Also, this research assessed opportunities and ways to expand the above more easily. Israel has a high level of technology in basic materials and information technology (IT). Meanwhile, Korea mainly exports automobiles and wireless communication equipment to Israel and imports semiconductor-related equipment and aviation components from Israel. Moreover, since the two countries signed a trade agreement in August 2019, they expect to expand trade with each other. As such, in order to promote multilateral trade and cooperation between the two countries, it is necessary to expand joint development opportunities through mutual collaboration on basic industries and smart mobility that Korea is in need. Further, Korean construction and materials companies related to the SOC industry in Israel should accelerate their local advances. In addition, more of the governmental support should be provided to foster regional experts and to offer various information to the companies entering the country.