• Journal of Korea Port Economic Association
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• v.38 no.3
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• pp.15-28
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• 2022

Bunkering refers to the supply of bunker fuel necessary for the ship operation, as well as minimizing the price and supply cost of fuel itself, and includes supplying good quality fuel oil in a timely manner and at the optimal port. Bunkering is an important criterion in terms of cost for shipping companies because bunkering involves a significant cost to the purchaser of bunkering from the time of initial purchase. This study aims to prioritize selection criteria for tramper companies to call port for bunkering. For this study, the variables were selected by analyzing the common criteria such as price, location, bunker quality and service and infrastructure etc. employed in previous studies. The AHP method was employed to prioritize the criteria in order. As a result of the analysis, the high level factors appeared in the order of price, location, bunkering quality and port service and infrastructure factors. The importance of price criterion and location criterion was found to be high. In the low level criterion of price, the bunker price per MT was ranked first in importance. In terms of location criteria, the location on the main trade route was high. In the low criteria of bunker quality and port service, the bunkering available types and bunker quality were found to be important factors, and in the low level criteria of infrastructure, anchorage and availability of bunkering during loading and discharging and port security factors were found to be important criteria. This study provides the guidelines for research designed to compare the bunkering port selection factors and to derive their importance suggesting the ways to enhance competitiveness as a bunkering port.

• Journal of Korea Entertainment Industry Association
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• v.14 no.6
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• pp.13-27
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• 2020

This study aims to analyze the effect on the adherence intention of enterprise image, trust, and relationship maintenance by the relation marketing in companies, especially in design companies, to examine the relationship establishment in the operation and communication between customers (users) on using the company's service and the member working for the company, and to suggest its substantiation of the mutual satisfaction effect. The research method was, first, analyzed based on the data collected after examining the published domestic and foreign papers, academic journals, publications, books, and internet in order to conduct the theoretic consideration. Also, for objective validity and empirical proof, the empirical analysis was conducted on the survey conducted and collected over two months for the employees of design companies living in Seoul and Gyeonggi-do, and the results are as follows. First, the result of verifying the relationship between relationship marketing and trust showed that the company's expertise does not significantly affect its trust while the company's communication and reputation affect significantly on trust. Second, the relationship between relationship marketing and sustainability has been verified that all variables, such as expertise, communication and reputation does not significantly effect the relationship maintenance. Third, the company's trust has significant effect on relationship maintenance. In addition, the implication and limitation of the study related to this were suggested in the conclusion.

• Journal of Korea Entertainment Industry Association
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• v.15 no.8
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• pp.247-254
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• 2021

The purpose of this study is to investigate the effects of action learning on the satisfaction of majors by cultivating task-solving ability through self-reflection in the form of team learning for a certain period of time in the form of team learning by using action learning for students taking convergence curriculum in universities. The subjects of the study were 40 students from the Department of Sports Rehabilitation, a convergence of the Department of Sports and Health Management and the Department of Physical Therapy located in Jeollanam-do. This was conducted to confirm the difference in the effect of satisfaction. Comparison of changes in groups of experimental groups with action learning teaching methods showed significant differences in self-directed learning skills, problem-solving skills, and major satisfaction(p<.001)(p<.05). A significant difference in self-directed learning ability, problem-solving ability, and major satisfaction was also shown in the comparison of changes in control groups that applied traditional teaching methods(p<.05). Comparison of changes between groups showed significant differences in self-directed learning skills, problem-solving skills and major satisfaction(p<.05). Applying the action learning teaching method to the level of students in the convergence course will improve self-directed learning skills, problem-solving skills, and major satisfaction, and further research will be needed to expand the target and add variables to combine qualitative research.

• Korean Journal of Head & Neck Oncology
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• v.37 no.2
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• pp.43-50
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• 2021

Background/Objectives: Shoulder function is an important aspect of health related quality of life (QOL). Neck dissection impairment index (NDII) is a simple shoulder-specific questionnaire. This study aimed to evaluate the association between QOL and NDII in patients who underwent neck dissection to validate the Korean version of NDII. Materials & Methods: This study enrolled 74 patients with head and neck cancer who underwent neck dissection from December 2013 to April 2014. Patients completed questionnaires on QOL including the European Organization of Research and Treatment of Cancer 30-item Core QOL questionnaire (EORTC QLQ-C30) and NDII which was translated into Korean. Validity was evaluated by calculating the Pearson correlation coefficient between NDII and EORTC QLQ-C30. Results: We compared preoperative, postoperative within a week, 1st and 3rd months NDII scores. The total NDII scores were 14.7, 47.4, 33.7 and 34.3 each. Clinical variables including gender, site of primary tumor, performing revision neck dissection, radiotherapy and flap reconstruction were not significantly associated with NDII. However NDII mean score of patients who underwent unilateral neck dissection over 3 levels is most increased after operation. During all periods NDII scores were significantly associated with functioning score. Although other scores are lower correlation than function scores, global health status scores and symptom scores are also correlation with NDII. Conclusion: NDII was valid instrument and can be used not only in the clinical practice to assess shoulder dysfunction but also in the simple instrument to evaluate global QOL in Korea patients with having neck dissection.

• Journal of Digital Convergence
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• v.19 no.11
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• pp.255-266
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• 2021

Investment demand for factory facilities has increased due to the balloon effect caused by housing price regulation. This study investigated the impact of the real estate market and macroeconomic factors on the bid price ratio of apartment auctions and factory auctions, focusing on the metropolitan area. To this end, we reviewed theories and previous studies on real estate auctions, and examined how macroeconomic variables affect bid price ratio of apartments and factories using the panel vector autoregressive model. It was found that the increase in the apartment bid price ratio increases as the participation in apartment auctions increases. However, as the factory bid price ratio increases, the factory bid price ratio does not increase, it was confirmed that the positive (+) relationship between the successful bid price ratio and the bid price ratioe does not exist, unlike previous studies. Based on the analysis results, it is suggested that the real estate market and macroeconomic factors should be considered for the stable operation of the related relevant auction system. This study has limitations in that it is limited to the metropolitan area. In the future, research that expands the scope of research to the whole country and provinces should be conducted.

• Journal of the Korea Institute of Building Construction
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• v.22 no.4
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• pp.359-370
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• 2022

Despite continuous efforts to reduce on-site safety accidents, the construction industry remains a high-risk sector with a high rate of fatal accidents. Design for Safety(DFS), which manages safety risk factors at the design stage, is being used as a method to lower the construction safety accident rate. However, due to limited knowledge, designers are unaware of the design-results risks during the different of the project lifecycle, including construction, operation, and maintenance. Effective DFS can be conducted if the designer understands the effect of the building shape on the safety accident rate and corresponding safety management cost(SMC). The cost of safety facilities such as fall prevention nets and safety fences will vary depending on the shape of the building. This study analyzes the outer perimeter length's impact on SMC. Following the data collection from 21 projects for this study, an analysis was conducted using the independent variables of the building perimeter(BP), building shape factor(BSF), and building area(BA), the dependent variable of SMC. The correlation R2 was found to be 0.876, 0.801 and 0.792 between the BP and SMC, BSF and SMC, BA and SMC, respectively, indicating that these factors were closely related.

• Economic Analysis
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• v.27 no.4
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• pp.1-42
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• 2021

The outlook for Korea's consumer price inflation rate has a profound impact not only on the Bank of Korea's operation of the inflation target system but also on the overall economy, including the bond market and private consumption and investment. This study presents the prediction results of consumer price inflation in Korea for the next three years. To this end, first, model selection is performed based on the out-of-sample predictive power of autoregressive distributed lag (ADL) models, AR models, small-scale vector autoregressive (VAR) models, and large-scale VAR models. Since there are many potential predictors of inflation, a Bayesian variable selection technique was introduced for 12 macro variables, and a precise tuning process was performed to improve predictive power. In the case of the VAR model, the Minnesota prior distribution was applied to solve the dimensional curse problem. Looking at the results of long-term and short-term out-of-sample predictions for the last five years, the ADL model was generally superior to other competing models in both point and distribution prediction. As a result of forecasting through the combination of predictions from the above models, the inflation rate is expected to maintain the current level of around 2% until the second half of 2022, and is expected to drop to around 1% from the first half of 2023.

• The Journal of Bigdata
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• v.7 no.2
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• pp.235-244
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• 2022

The rental history data of public bicycles in Seoul were analyzed to examine how pandemic phenomena such as COVID-19 caused changes in people's micro mobility. Data for 2019 and 2021 were compared and analyzed by dividing them before and after COVID-19. Data were collected from public data portal sites, and data marts were created for in-depth analysis. In order to compare the changes in the two periods, the riding direction type dimension and the rental station type dimension were added, and the derived variables (rotation rate per unit, riding speed) were newly created. There is no significant difference in the average rental time before and after COVID-19, but the average rental distance and average usage speed decreased. Even in the mobility of Ttareungi, you can see the slow rhythm of daily life. On weekdays, the usage rate was the highest during commuting hours even before COVID-19, but it increased rapidly after COVID-19. It can be interpreted that people who are concerned about infection prefer Ttareungi to village buses as a means of micro-mobility. The results of data mart-based visualization and analysis proposed in this study will be able to provide insight into public bicycle operation and policy development. In future studies, it is necessary to combine SNS data such as Twitter and Instagram with public bicycle rental history data. It is expected that the value of related research can be improved by examining the behavior of bike users in various places.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.1D
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• pp.33-40
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• 2009

The critical lag of crosswalk pedestrians is an important parameter in analyzing traffic operation at unsignalized crosswalks, however there is few research in this field in Korea. The purpose of this study is to develop a model to estimate the critical lag. Among the elements which influence the critical lag, the age of pedestrians and the length of crosswalks, which have fuzzy characteristics, and the each lag which is rejected or accepted are collected on crosswalks of which lengths range from 3.5 m to 10.5 m. The values of the critical lag range from 2.56 sec. to 5.56 sec. The age and the length are divided to the 3 fuzzy variables each, and the critical lag of each case is estimated according to Raff's technique, so a total of 9 fuzzy rules are established. Based on the rules, an ANFIS (Adaptive Neuro-Fuzzy Inference System) model to estimate the critical lag is built. The predictability of the model is evaluated comparing the observed with the estimated critical lags by the model. Statistics of $R^2$, MAE, MSE are 0.96, 0.097, 0.015 respectively. Therefore, the model is evaluated to explain the result well. During this study, it is found that the critical lag increases rapidly over the pedestrian's age of 40 years.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.4D
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• pp.323-330
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• 2010

The time in port for vessels is one of the important factors for analyzing the operation status and the capacity of ports. In addition, the time in port for vessels can be directly used for estimating the greenhouse gas emissions resulted from vessels in port. However, it is unclear which variables can affect the time in port for vessels and what the marginal effect of each variable is. With these challenges in mind, the study analyzes the time in port for vessels arriving and departing port of Busan by using a parametric survival model. The results show that the log-logistic accelerated failure time model is appropriate to explain the time in port for 19,167 vessels arriving and departing port of Busan in 2008, in which the time in port is significantly affected by gross tonnage of vessels, service capacity of terminal, and vessel type. This study also shows that the greenhouse gas emission resulted from full-container vessels, which accounted for about 61% of all vessels with loading/unloading purpose arriving and departing port of Busan in 2008, is about "17 ton/vessel" in the boundary of port of Busan. However, the hotelling greenhouse gas emissions resulted from non-container vessels (3,774 vessels; 20%) are greater than those from the full-container vessels. Hence, it is necessary to take into account more efficient port management polices and technologies to reduce the service time of non-container vessels in port of Busan.