• Korean Journal of Construction Engineering and Management
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• v.24 no.2
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• pp.88-97
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• 2023

The purpose of this study is to forecast future changes in the construction market following the reorganization of the construction production system by analyzing the possible market size in which general contractors and specialty contractors may participate in each other, and by carrying out a survey. The ratio of correlation between general construction and specialty construction industries was derived by analyzing the relevance of work area of general contractors and specialty contractors, the similarity of registration standards, and the market in which general contractors and specialty contractors may be able to mutually participate. In order to overcome the limitation of previous studies which analyze the changes in construction market based on the statistical data, and to analyze in more detail the impact of reorganization of construction production system from market participants' view, a survey targeting general contractors and specialty contractors for their willingness and method of participating in the mutual market was conducted. As a result of the survey, it was found that 52% of general contractors were willing to participate in the specialized construction market and 55.1% of specialty contractors were willing to participate in the general construction market. It was found that there was a high willingness to participate in the earthworks, reinforced concrete works, facility maintenance and management, water and sewage facility works, and interior works, and high competition is expected for projects with a scale of 500 million to less than 3 billion won. Through this study, it will be possible for general and specialty contractors to understand the changes in the construction market due to the reorganization of the construction industry production system, and to respond effectively to these changes.

• Journal of the Korean Society of Floral Art and Design
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• no.41
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• pp.45-59
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• 2019

The characters that could be connected to diverse cultural contents have formed diverse platforms with the development of digital technology, and the size of the relevant industry and market is rapidly growing. Recently, the utilization of character emoticons for smartphone messenger has been rapidly increased, so that the characters are settled down as a tool for non-verbal communication, on top of drawing attention as an independent area. With the expansion of character market, the importance of design that could give interest and familiarity to consumers is more emphasized. The body proportion of characters includes the implicative and symbolic meanings that could express diverse personalities. Thus, this study examined the body proportion of the characters with the high consumers' preference, and then analyzed the characteristics of formative elements of character design in accordance with the body proportion. In the results of the analysis, the exaggerated form of SD characters in two or three-head figure, and the realistic Real characters in seven or eight-head figure were preferred. For the SD characters, the colors with a high chroma showing the cute and cheerful image were used. For the Real characters, the cubic effect was expressed through the colors with active images and the light and shade of color. Even though the SD characters have limited motions due to the omitted body parts, the facial movements of animation characters are exaggerated while the Real characters describe the realistic and dynamic motions.

• Journal of Korea Trade
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• v.27 no.2
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• pp.61-76
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• 2023

Purpose - The digital service trade has become an important driver of the global service trade. The main purpose of this study is to explore the influencing factors of digital service exports from China and Korea to RCEP sample countries respectively, and to comprehensively study the export potential of China and Korea to RCEP countries, so as to provide theoretical guidance and a decision-making reference to promote digital service trade exports and digital economy development in China and Korea. Design/methodology - First, the stochastic frontier gravity model was improved by introducing nonefficiency factors affecting digital services trade, extending the gravity model of traditional services trade exports to digital services trade exports. Secondly, the panel data of China and Korea for the eight sample countries of RCEP from 2011 to 2021 were adopted for the empirical analysis of digital service export potential by a stochastic frontier model. Findings - China's economic growth plays a role in increasing China's digital service trade exports, while Korea's economic growth does not play a significant role in increasing Korea's digital service trade exports. However, the economic growth of trading partner countries can play a significant role in boosting the digital service trade in both China and Korea, and comparison shows that Korea has higher resilience in the digital services trade than China. In addition, the market size of target countries plays a positive role in promoting the digital service trade exports of both China and Korea, and the increase in the value-added share of services in target countries will lead to a decrease in the digital service trade exports of both China and Korea. Originality/value - This study is innovative in terms of research perspective and method. Academic research on the export potential of international trade has been extensive, but most studies are based on the perspective of the goods trade, fewer studies are based on the perspective of the service trade, and there are almost no studies based on the perspective of digital service trade. There is a gap based on the comparative analysis of the export potential of the digital service trade between China and Korea. This study extends the gravitational model of traditional service trade exports to digital service trade exports to comparatively analyze the export potential of China and Korea to RCEP countries. This study addresses this limitation by analyzing a comparative analysis of the digital service trade export potential of China and Korea.

• Journal of Korea Trade
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• v.27 no.1
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• pp.139-158
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• 2023

Purpose - The study of co-movements between stock markets is a crucial area of finance and has recently received much interest in a variety of studies, especially in international finance. Stock market co-movements are a major phenomenon in financial markets, but they are not necessarily independent of the real market. Several studies support the idea that bilateral trade linkages significantly impact stock market correlations. Motivated by this perspective, this study investigates whether real market integration due to trade agreements brings about financial market integration in terms of stock market co-movement. Design/methodology - Over the 10 free trade agreements (FTAs) signed by the United States, using a dynamic conditional correlations (DCC) multivariate GARCH (MGRACH) model, we empirically measure the degree of integration by finding DCCs between the US market and the partner country's market. We then track how these correlations evolve over time and compare the results before and after trade agreements. Findings - According to the empirical results, there are positive return spillover effects from the US market to eight counterpart equity markets, except Jordan, Morocco, and Singapore. Especially Mexico, Canada, and Chile have large return spillover effects at the 1% significance level. All partner countries of FTAs generally have positive correlations with the US over the entire period, but the size and variance are somewhat different by country. Meanwhile, not all countries that signed trade agreements with the United States showed the same pattern of stock market co-movement after the agreement. Korea, Mexico, Chile, Colombia, Peru, and Singapore show increasing DCC patterns after trade agreements with the US. However, Canada, Australia, Bahrain, Jordan, and Morocco do not show different patterns before and after trade agreements in DCCs. These countries generally have the characteristic of relatively lower or higher co-movements in stock markets with the US before the signing of the FTAs. Originality/value - To our knowledge, few studies have directly examined the linkages between trade agreements and stock markets. Our approach is novel as it considers the problem of conditional heteroscedasticity and visualizes the change of correlations with time variations. Moreover, analyzing several trade agreements based on the United States enables the results of cross-country pairs to be compared. Hence, this study provides information on the degree of stock market integration with countries with which the United States has trade agreements, while simultaneously allowing us to track whether there have been changes in stock market integration patterns before and after trade agreements.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2020.11a
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• pp.163-164
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• 2020

Along with the increase in global volume of goods, logistics companies are trying to reduce costs by increasing the size of ships carrying cargo, increasing the efficiency of quantitative equipment at ports, and unmanned electric vehicles on land. Korean naval ports are also facing the same situation as the global trend. In the past, small and medium-sized ships such as FF, PCC, and beheaded eagles are being retired for their longevity, and their positions are being replaced by large ships such as KDX, FFG, and LST-II. In particular, large ships such as Dokdo and the next light aircraft carriers are also being prepared. Unlike general merchant ships, naval ships require periodic inspections and preventive maintenance, so repair piers such as maintenance depots are in operation. The naval maintenance depot mainly uses trailers, trucks, and truck-type cranes to carry out loading and unloading of heavy ships, and the application or development of automation and unmanned equipment performed by the private sector is inadequate, and self-improvement cases are also very weak. This study aims to improve the efficiency of the military logistics system through research on the logistics system such as transport, storage and unloading of heavy goods and maintenance products of naval ships.

• Journal of Korea Entertainment Industry Association
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• v.10 no.4
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• pp.77-92
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• 2016

In this study, the relationship of images and sounds of the animations "Dots" and "Loops" which Norman McLaren animated with his Animated sound technique when he worked at Guggenheim museum at New York, are analyzed through the audiovisual analysis theory by Michel Chion, and through the theory of synchronism/asynchronism and parallelism/counterpoint by Siegfried Kracauer. For the results of the analysis, there are a few difference between "Dots" and "Loops" regarding the aspect of sound arrangement and expressive aspect of abstract animation. However, there are being of two main elements of sound, composing with monophony sound, making musical structure with sound effects, and the emphasizing of parallelism with synchronization bewteen images and sounds in common with both "Dots" and "Loops". In "Dots" and "Loops", there are close correlations between pitch of sound and arrangement/shape of image, between loudness of sound and size of image, and between length of sound and length/shape of image. The image and sound of "Dots" and "Loops" have equal relationship each other, rather than subordinate relationship according as image become sound and the sound become new image with the animated sound technique. "Dots" and "Loops" show tendency of minimal art and music video. Since these two films, and remind about the new approach to sound creation in today's animation production.

• Journal of Marine Life Science
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• v.8 no.2
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• pp.121-127
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• 2023

The study was performed in order to understand the association between organic matter content in the sediments and the distribution of macrobenthos in the intertidal zone of the Muan bay. The sediment samples obtained from 21 sampling sites in August 2019 were analyzed for sediment composition and organic matter content (Ignition loss; IL and Total organic carbon; TOC). Further the macro benthos was sorted and enumerated. The sediments of inner area of bay has coarser composition where mouth part of bay, the sediments were predominantly silty. The highest organic matter content (both of IL and TOC) was measured at station 10 located near the Mokpo area while the lowest values was measured at station 20 adjacent to the north side of the bay. The 4 most abundant species accounted for more than 10% of all specimens were Assiminea sp., Musculista senhousia, Cerithideopsilla cingulate and Heteromastus filiformis. The maximum number of species and density were observed at station 10. Cluster analysis and non-metric multidimensional scaling (MDS) allow identification of four benthic assemblages based on species abundance. The correlation analysis revealed that there was a significant difference (p<0.05) in the density with TOC. Based on the analysis; it was found that the distribution of macrobenthos varied with the differences in sediment composition and organic matter content.

• Composites Research
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• v.36 no.5
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• pp.289-296
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• 2023

In this study, we investigated the electromagnetic properties and microwave absorption characteristics of M-type hexagonal ferrites, which are known as millimeter-wave absorbing materials, according to their calcination temperature. The M-type ferrites synthesized using a molten salt-based sol-gel method exhibited a single-phase M-type crystal structure at calcination temperatures above 850℃. The synthesized particle size increased as well with the calcination temperature. Saturation magnetization increased gradually with increasing calcination temperature, but coercivity reached a maximum at 1050℃ and then rapidly decreased. After preparing a thermoplastic polyurethane (TPU) composite containing 70 wt% of M-type ferrites, we measured the complex permittivity and permeability in the Q-band (33-50 GHz) and V-band (50-75 GHz) frequency ranges, where ferromagnetic resonance occurred. Strong magnetic loss from ferromagnetic resonance occurred in the 50 GHz band for all composite samples. Based on the measured results, we calculated the reflection loss of the TPU/M-type ferrite composite. By calculating the reflection loss of the M-type ferrite composite, the M-type ferrite calcined at 1250℃ showed excellent electromagnetic wave absorption performance of more than -20 dB at 52 GHz with a thickness of about 0.5 mm.

• Korean Journal of Radiology
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• v.22 no.8
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• pp.1240-1252
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• 2021

Objective: To compare the accuracy for detecting breast cancer in the diagnostic setting between the use of digital breast tomosynthesis (DBT), defined as DBT alone or combined DBT and digital mammography (DM), and the use of DM alone through a systematic review and meta-analysis. Materials and Methods: Ovid-MEDLINE, Ovid-Embase, Cochrane Library and five Korean local databases were searched for articles published until March 25, 2020. We selected studies that reported diagnostic accuracy in women who were recalled after screening or symptomatic. Study quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. A bivariate random effects model was used to estimate pooled sensitivity and specificity. We compared the diagnostic accuracy between DBT and DM alone using meta-regression and subgroup analyses by modality of intervention, country, existence of calcifications, breast density, Breast Imaging Reporting and Data System category threshold, study design, protocol for participant sampling, sample size, reason for diagnostic examination, and number of readers who interpreted the studies. Results: Twenty studies (n = 44513) that compared DBT and DM alone were included. The pooled sensitivity and specificity were 0.90 (95% confidence interval [CI] 0.86-0.93) and 0.90 (95% CI 0.84-0.94), respectively, for DBT, which were higher than 0.76 (95% CI 0.68-0.83) and 0.83 (95% CI 0.73-0.89), respectively, for DM alone (p < 0.001). The area under the summary receiver operating characteristics curve was 0.95 (95% CI 0.93-0.97) for DBT and 0.86 (95% CI 0.82-0.88) for DM alone. The higher sensitivity and specificity of DBT than DM alone were consistently noted in most subgroup and meta-regression analyses. Conclusion: Use of DBT was more accurate than DM alone for the diagnosis of breast cancer. Women with clinical symptoms or abnormal screening findings could be more effectively evaluated for breast cancer using DBT, which has a superior diagnostic performance compared to DM alone.

• Korean Journal of Radiology
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• v.23 no.10
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• pp.939-948
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• 2022

Objective: Evidence supports the efficacy of coronary computed tomography angiography (CCTA)-based risk scores in cardiovascular risk stratification of patients with suspected coronary artery disease (CAD). We aimed to compare two CCTA-based risk score algorithms, Leiden and Confirm scores, in patients with diabetes mellitus (DM) and suspected CAD. Materials and Methods: This single-center prospective cohort study consecutively included 1241 DM patients (54.1% male, 60.2 ± 10.4 years) referred for CCTA for suspected CAD in 2015-2017. Leiden and Confirm scores were calculated and stratified as < 5 (reference), 5-20, and > 20 for Leiden and < 14.3 (reference), 14.3-19.5, and > 19.5 for Confirm. Major adverse cardiovascular events (MACE) were defined as the composite outcomes of cardiovascular death, nonfatal myocardial infarction (MI), stroke, and unstable angina requiring hospitalization. The Cox model and Kaplan-Meier method were used to evaluate the effect size of the risk scores on MACE. The area under the curve (AUC) at the median follow-up time was also compared between score algorithms. Results: During a median follow-up of 31 months (interquartile range, 27.6-37.3 months), 131 of MACE were recorded, including 17 cardiovascular deaths, 28 nonfatal MIs, 64 unstable anginas requiring hospitalization, and 22 strokes. An incremental incidence of MACE was observed in both Leiden and Confirm scores, with an increase in the scores (log-rank p < 0.001). In the multivariable analysis, compared with Leiden score < 5, the hazard ratios for Leiden scores of 5-20 and > 20 were 2.37 (95% confidence interval [CI]: 1.53-3.69; p < 0.001) and 4.39 (95% CI: 2.40-8.01; p < 0.001), respectively, while the Confirm score did not demonstrate a statistically significant association with the risk of MACE. The Leiden score showed a greater AUC of 0.840 compared to 0.777 for the Confirm score (p < 0.001). Conclusion: CCTA-based risk score algorithms could be used as reliable cardiovascular risk predictors in patients with DM and suspected CAD, among which the Leiden score outperformed the Confirm score in predicting MACE.