• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.345-353
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• 2020

On conventional railway lines, trains with different speeds are operated. Therefore, trains moving on curved sections with cants must accept various ranges of balanced cants, cant deficiency, and cant excess, which is essential for the comfort and safety of train operation. In this study, the correlation between the curve radius, cant, and train speed on a track was analyzed to check the cant range that satisfies the criteria of train types, operation speed, cant deficiency, and cant excess. Also, the range of setting the cant by the curve radius and balanced cant were calculated by a regression analysis of train speed according to the frequency of operation in the case of mixed trains. The results could make it possible to improve the speed of the operation route, reduce the loss of ride quality, reduce the risk of derailing caused by cant deficiency, and minimize the load deflection by excess cant. This will ensure the safety of trains running on curves and improve the efficiency of track maintenance.

• Journal of the Korean Institute of Landscape Architecture
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• v.50 no.2
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• pp.76-88
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• 2022

Urban parks play the role of providing leisure spaces for people in their everyday life along with serving ecological functions in the city. Although urban parks aim to satisfy the needs of users visiting the park, most urban parks are currently uniformly created and maintained without considering the environmental characteristics based on the needs of users. This study thus analyzed parks that underwent modifications in line with the revised Park Act in 2005. There were 45 parks whose types were legally changed, of which 21 were changed from children's parks to small parks, and 19 were changed to utilize and highlight the themes such as cultural parks and historical parks. Among the parks whose types have changed, the ratio of amenities in cultural and historic parks has increased, while the facility area in small parks has decreased and the green area has increased in its place. As a result of analyzing the changes to the park facility area, it was confirmed that increasing park amenities has a positive effect in pursuing revitalization of use through park maintenance, but has a negative consequence of significantly decreasing green area. It is necessary to reorganize the park type classification system to reflect the park environment and prepare guidelines for a new installation standard by park type to expand the net function of parks in cities and maintain the sustainable ecological environment. Through in-depth discussions on the facilities of park types, it is anticipated that innovative and multilateral research could be conducted to prepare improvement measures tailored to the guidelines of urban park types in years to come.

• The Journal of the Convergence on Culture Technology
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• v.8 no.6
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• pp.685-691
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• 2022

This study was based on the steel composite concrete box structure (Transfer girder) which was installed to support the skyscrapers directly above the subway line. In this study, it was analytically proved that the cause of cracks on the steel composite concrete box structure were the shrinkage cracks by comparing the results of crack investigation and numerical analysis. As the results, it was found that the internal temperature difference between concrete and steel members occurred according to the shape of the steel frame embedded in concrete, the location of vertical stiffener, and the closed section area. The narrower spacing of vertical stiffener was occurred the internal temperature concentration of the structure and the temperature difference increased. And the location of higher thermal strain and temperature were similar to the location of actual cracks by the visual inspection. Therefore, the internal temperature concentration parts were formed according to the presence and spacing of the vertical stiffeners and the inspection passage in the central part of the structure. The shrinkage cracks were occurred by the restrained of temperature expansion and contraction of the concrete. As the results of this study, it was important to separate and manage the non-structural cracks caused by shrinkage and the structural cracks in the maintenance of serviced steel-composite concrete structures.

• Journal of KIISE:Databases
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• v.34 no.4
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• pp.343-356
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• 2007

Due to advances in position monitoring technologies such as global positioning systems and sensor networks, recent position information of moving objects has the form of streaming data which are updated continuously and rapidly. In this paper we propose an efficient trajectory maintenance method that stores the streaming position data of moving objects in the limited size of storage space and estimates past positions based on the stored data. For this, we first propose a new concept of incremental extraction of position information. The incremental extraction means that, whenever a new position is added into the system, we incrementally re-compute the new version of past position data maintained in the system using the current version of past position data and the newly added position. Next, based on the incremental extraction, we present an overall framework that stores position information and estimates past positions in the stream environment. We then propose two polynomial-based methods, line-based and curve-based methods, as the method of estimating the past positions on the framework. We also propose three incremental extraction methods: equi-width, slope-based, and recent-emphasis extraction methods. Experimental results show that the proposed incremental extraction provides the relatively high accuracy (error rate is less than 3%) even though we maintain only a little portion (only 0.1%) of past position information. In particular, the curve-based incremental extraction provides very low error rate of 1.5% even storing 0.1% of total position data. These results indicate that our incremental extraction methods provide an efficient framework for storing the position information of moving objects and estimating the past positions in the stream environment.

• Journal of Digital Convergence
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• v.15 no.8
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• pp.103-114
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• 2017

With the development of IT technology and the establishment of logistics infrastructure, online shopping market and online fresh food market are growing. The purpose of this study is to find a plan to activate Fresh Logistics through online shopping mall using BCG matrix and Importance Performance Analysis for online shopping companies. Firstly, the BCG matrix results Companies in 'cash cow', 'question mark', and 'dog' areas are in need of improvement. In order to improve this situation, it is necessary to activate the Fresh logistics market which is currently growing. Fresh logistics can be activated by investing in the maintenance and strengthening areas and key investment areas by minimizing the expenditure on the non-priority and excess areas according to the results of IPA. Therefore, it is expected that online shopping companies will be improved by activating online shopping market and online fresh logistics market.

• The Journal of the Korea Contents Association
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• v.13 no.11
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• pp.957-967
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• 2013

While a vast number of cad drawings are produced in the life cycle of construction projects from the planning, design, and construction phases to the maintenance and control phases, the creation and distribution of non-standard drawings make it difficult for the construction parties to communicate with one another and to recycle, maintain, and control drawings by project phase. The Korea standard of CAD drawing in construction CALS/EC, which stipulates the standard for construction CAD drawings, is based on roads, rivers, and railways in line- and unit-based structures, allowing the creation of standardized CAD drawings. Such standard, however, cannot be easily applied to construction projects with multiple facilities like harbors, housing sites, or lands consisting of surface forms. In particular, port field consist of complex docks and amenities located in a certain coastal area based on multiple objectives. They also contain the concept of housing sites, like background land, and are composed of various civil engineering facilities, construction facilities, and port field, so that the existing CAD drawing standard cannot be easily implemented. Therefore, the purpose of this study is to maximize the efficiency of the information related to drawing information and to ultimately support smooth information exchanges in construction design by conducting a development research on the expansion of the CAD drawing standard that meets the needs of port field.

• Biomedical Science Letters
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• v.13 no.4
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• pp.251-261
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• 2007

A myofiber of skeletal muscle is composed of myofibrils, sarcolemma (plasma membrane), and constameres, which anchor the myofibrils to the sarcolemma. Achvillin is a recently identified F-actin binding muscle protein, co-isolates with dystrophin and caveolin-3 in low-density sarcolemma of striated muscle, and colocalizes with dystrophin at costameres, the specialized adhesion sites in muscle. Archvillin also binds to nebulin and localizes at myofibrillar Z-discs, the lateral boundaries of the sarcomere in muscle. However other roles of archvillin on the dynamics of myofibrillogenesis remain to be defined. The goal of this study is, by using siRNA-mediated gene silencing technique, to investigate the effect of archvillin on the dynamics of myofibrillogenesis in cell culture of a mouse skeletal myogenic cell line (C2C12), where presumptive myoblasts withdraw from the cell cycle, fuse, undergo de novo myofibrillogenesis, and differentiate into mature myotubes. The roles of archvillin in the assembly and maintenance of myofibril and during the progression of myofibrillogenesis induced in skeletal myoblast following gene silencing in the cell culture were investigated. Fluorescence microscopy demonstrated that the distribution of archvillin was changed along the course of myofibril assembly with nebulin, vinculin and F-actin and then located at Z-lines with nebulin. Fluorescence microscopy demonstrated that knockdown of mouse archvillin expression led to an impaired assembly of new myofibrillar clusters and delayed fusion and myofibrillogenesis although the mouse archvillin siRNA did not affect those expressions of archvillin binding proteins, such as nebulin and F-actin. This result is corresponded with that of RT-PCR and western blots. When the perturbed archvillin was rescued by co-transfection with GFP or Red tagged human archvillin construct, the inhibited cell fusion and myotube formation was recovered. By using siRNA technique, archvillin was found to be involved in early stage of myofibrillogenesis. Therefore, the current data suggest the idea that archvillin plays critical roles on cell fusion and dynamic myofibril assembly.

• The korean journal of orthodontics
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• v.40 no.5
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• pp.325-333
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• 2010

Objective: The aim of this study was to illustrate the circumferential comfortable retainer (CCR) as a removable maxillary retainer with good potential patient compliance and to evaluate the discomfort of the retainers including distorted speech, gagging sensation and appliance discomfort. Methods: Sixty-six orthodontic patients (male, 23; female, 43; mean age, $23.42{\pm}10.19$ years) who received orthodontic treatment with fixed orthodontic appliances were randomly assigned to two groups after debonding, a conventional wraparound retainer (CWR) group that fully covers the palate with an acrylic plate and a highly polished surface, and a circumferential comfortable retainer (CCR) group which has a horseshoe shaped base plate with three folds on the anterior region. A questionnaire that had a visual analog scale (VAS) which consists of a 100-mm horizontal line with 2 end-points labeled "no discomfort" on the left and "worst discomfort" on the right, with regard to distorted speech, gagging sensation and discomfort, was administered to patients after 4 weeks of retainer wear. The Mann-Whitney test was used to test the hypothesis that there was no difference between the two retainers. Results: Comparing distorted speech and discomfort, the CCR group significantly had lower values than the CWR group ($p$ < 0.05). Comparing gagging sensation, the CCR group had lower values than the CWR group but there were no statistically significant differences between groups ($p$ = 0.146). Conclusions: In conclusion, the results suggest that the circumferential comfortable retainer (CCR) might facilitate patient compliance and thereby improve the maintenance of the fixed orthodontic treatment outcome.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.4
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• pp.143-160
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• 2019

The domestic pharmacy market has undergone a lot of changes starting from the division of medicine. Along with the division of medicine, patients who had previously visited the pharmacy were moved to a hospital or clinic. As the pharmacy became more dependent on the illness and the clinic, the pharmacy began various activities to search for ways other than prescription drugs. At this time, the importance of distribution was emphasized around the time, and as the need to strengthen the competitiveness of pharmacies increased, they rapidly grew into the franchise market. Pharmacy franchise companies continue to lecture on academic management to strengthen the expertise of pharmacists' functions in line with the pharmacy market, which is different from ordinary franchise, in addition to private brand products for pharmacies, diversifying pharmacy handling items, And strengthening its market competitiveness. but research to support it are insufficient. As a research to help this, we analyzed factors affecting the intention of re-contracting and recommendation intention that affect the maintenance and expansion size of the drugstore franchise market. As a result showed the intention of re-contracting and the intention of recommending are affected by positive influence in brand trust. In addition, Brand Promise, Employee authenticity, Originality, Product excellence, Brand reputation, Brand identification, Educational Satisfaction were found to affect brand trust.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.27 no.4
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• pp.314-320
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• 2001

Matrix metalloproteinases have long been viewed as ideal candidates for proteinases that enables tumor cells to permeated basement membrane defenses and invade surrounding tissue. There is growing evidence that the MMPs have an expanded role, as they are important for the creation and maintenance of a microenvironment that facilitates growth and angiogenesis of tumors at primary and metastatic sites. MT-MMPs are not secreted but instead remaining attached to cell surfaces. Although not all of the MT-MMPs are fully characterized, MT-MMPs have important role in localizing and activating secreted MMPs. The MMP genes are transcriptionally responsive to a wide variety of oncogene, growth factors, cytokine, and hormones. Currently, a number of MMP inhibitors are being developed and some have reached clinical trials as anti-metastatic or anti-cancer therapies. MT1-MMP is involved in the activation of proMMP-2. MT1-MMP is significant not only as a tumor marker but as a new target for chemotherapy against cancer. The purpose of this study was to evaluate the effects of protein kinase C inhibitor(genistein) on the proliferation of HT1080 and expression of MT1-MMP mRNA. Human fibrosarcoma cell line HT1080 was cultured and divided 2 groups. The experimental group was treated with $100{\mu}M$ genistein and incubated 12h, 24h for $[3^H]-thymidine$ uptake assay and northern hybridization individually. And the control group was treated with same amount of PBS for the above procedures. $[3^H]-thymidine$ incorporation was measured with ${\beta}$ ray detector. And RT-PCR and northern blotting for MT1-MMP mRNA was performed. The results were as follows 1. $[3^H]-thymidine$ uptake was reduced in experimental group with statistical significance. 2. MT1-MMP mRNA expression was significantly reduced in experimental group. These results showed that protein kinase C inhibitor (genistein) inhibited proliferation of HT1080 and almost completely blocked transcription of MT1-MMP mRNA. So, it is possible to use the protein kinase inhibitor (genistein) as anti-metastatic and anti-proliferative agent.