• The Journal of Korean Academy of Prosthodontics
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• v.60 no.3
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• pp.231-238
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• 2022

Purpose. This study aimed to investigate the effect of different veneering methods on the tensile bond strength between polyetherketoneketone (PEKK) and denture base resins. Materials and methods. A total of 80 PEKK T-shaped specimens were fabricated and the primer (Visio.link) was applied after airborne-particle abrasion with 110 ㎛ alumina oxide powder. According to the veneering method, the specimens were divided into four groups (n = 20) to be veneered with the gingival colored packable photopolymerized composite resin (SR Adoro); flowable photopolymerized composite resin, (Crea.lign); heat-polymerized resin (Vertex); and self-polymerized resin (ProBase Cold). Each group was divided into two subgroups (n = 10) according to the artificial thermal aging. After the tensile bond strength measurement via universal testing machine, the fracture sections of all specimens were observed. Two-way ANOVA and Tukey's HSD post hoc test were used for the statistical analysis (α = .05). Results. The results of the two-way ANOVA showed statistically significant differences in the tensile bond strength according to the veneering method and artificial thermal aging of denture base resins (P<.001). The highest tensile bond strength showed in the packable photopolymerized resin group before and after the artificial thermal aging. The lowest tensile bond strength showed in the heat-polymerized resin group. The mixed and adhesive fracture showed in all groups. Conclusion. The veneering method and artificial thermal aging can influence in the tensile bond strength between the resin and PEKK. The artificial thermal aging can reduce the tensile bond strength.

• Journal of Korea Water Resources Association
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• v.55 no.10
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• pp.761-774
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• 2022

Accurate hydrologic prediction is essential to analyze the effects of drought, flood, and climate change on flow rates, water quality, and ecosystems. Disentangling the uncertainty of the hydrological model is one of the important issues in hydrology and water resources research. Hydrologic data assimilation (DA), a technique that updates the status or parameters of a hydrological model to produce the most likely estimates of the initial conditions of the model, is one of the ways to minimize uncertainty in hydrological simulations and improve predictive accuracy. In this study, the two ensemble-based sequential DA techniques, ensemble Kalman filter, and particle filter are comparatively analyzed for the daily discharge simulation at the Yongdam catchment using airGRdatassim. The results showed that the values of Kling-Gupta efficiency (KGE) were improved from 0.799 in the open loop simulation to 0.826 in the ensemble Kalman filter and to 0.933 in the particle filter. In addition, we analyzed the effects of hyper-parameters related to the data assimilation methods such as precipitation and potential evaporation forcing error parameters and selection of perturbed and updated states. For the case of forcing error conditions, the particle filter was superior to the ensemble in terms of the KGE index. The size of the optimal forcing noise was relatively smaller in the particle filter compared to the ensemble Kalman filter. In addition, with more state variables included in the updating step, performance of data assimilation improved, implicating that adequate selection of updating states can be considered as a hyper-parameter. The simulation experiments in this study implied that DA hyper-parameters needed to be carefully optimized to exploit the potential of DA methods.

• The Journal of the Korea Contents Association
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• v.22 no.10
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• pp.658-675
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• 2022

With the advent of the OTT platform, the world has become an era in which the same media content is shared and reacted in real time by being grouped into one culture. This study attempts a producer study of web novel writers, who are producers of the web novel market that is expanding into webtoons, dramas, and movies with IP (intellectual property rights) of the original story at a time when Korean K-content such as "Squid Game" and "Weird Lawyer Woo Young-woo" leads the global market. In this study, web novel writers were viewed as producers of commercial media content, not just 'Novelist', and their identities and characteristics of the labor process were examined. Web novel writers began writing web novels as a side job or two jobs, and cited the fact that they can make profits alone without barriers to entry and without incurring capital or facility costs. Although there is no barrier to entry, most writers experience severe failure in their first work, which is attributed to the misunderstanding that the word "writer" is someone who writes what they want in any genre. Web novels are different, so writers go through the process of realizing that in order to succeed by writing web novels, they must be thoroughly in the audience's shoes and write them according to the trends and codes they want. Web novel writers expressed their identity as "story sellers," "story producers," "people who can produce IP alone," and "people who satisfy fantasies that cannot be achieved in reality," and in common, there was a strong sense of being a person who provides stories and makes profits or sales. Regarding the burden of writing a huge amount of web novels, the writer with a high income expressed a generous position that "the income is higher than the effort," but ordinary writers complained of difficulties in the hard work, saying, "It seems like I am working hard on writing that I have to write constantly.

• Journal of the Korean Orthopaedic Association
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• v.55 no.2
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• pp.135-142
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• 2020

Purpose: This paper presents the long term follow-up results of arthroscopic partial repair for massive irreparable rotator cuff tears using a biceps long head auto graft. Materials and Methods: Forty-one patients with massive irreparable rotator cuff tear, who underwent arthroscopic repair, were reviewed retrospectively. Patients who underwent arthroscopic partial repair using a biceps long head auto graft were assigned to group 1, and patients in group 2 underwent arthroscopic partial repair alone. Patients with a less than 50% partial tear of the long head biceps tendon were included in this study. The clinical scores were measured using a visual analogue pain scale (VAS) for pain, range of motion (ROM), The University of California, Los Angeles shoulder score (UCLA), American Shoulder and Elbow Surgeons Shoulder Score (ASES), and Korean Shoulder Scoring System (KSS) scores preoperatively and at the final follow-up. The acromiohumeral interval (AHI) was measured using plain radiographs taken preoperatively and at the final follow-up, and re-tear was evaluated using postoperative ultrasound or magnetic resonance imaging at the last follow-up. Results: The mean age of the patients was 62.1±12.7 years, and the mean follow-up period was 90.3±16.8 months. No significant differences in the VAS and ROM (forward flexion, external rotation, internal rotation) were found between the two groups (p=0.179, p=0.129, p=0.098, p=0.155, respectively). The UCLA (p=0.041), ASES (p=0.023), and KSS (p=0.019) scores showed functional improvements in group 1 compared to group 2. At the last follow-up, the measured AHI values were 9.46±0.41 mm and 6.86±0.64 mm in group 1 and 2, respectively (p=0.032). Re-tear was observed in six out of 21 cases (28.6%) in group 1 and nine out of 20 cases (45.0%) in group 2; the retear rate was significantly lower in group 1 than in group 2 (p=0.011). Conclusion: Arthroscopic partial repair for a massive irreparable rotator cuff tear using a biceps long head auto graft has significant clinical usefulness in functional recovery and decreases the re-tear rates after surgery than arthroscopic partial repair alone, showing favorable results after a long-term follow-up.

• Journal of Korea Port Economic Association
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• v.37 no.4
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• pp.161-173
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• 2021

The shipping industry plummeted and was depressed due to the global economic crisis caused by the bankruptcy of Lehman Brothers in the US in 2008. In 2020, the shipping market also suffered from a collapse in the unstable global economic situation due to the COVID-19 pandemic, but unexpectedly, it changed to an upward trend from the end of 2020, and in 2021, it exceeded the market of the boom period of 2008. According to the Clarksons report published in May 2021, the decrease in cargo volume due to the COVID-19 pandemic in 2020 has returned to the pre-corona level by the end of 2020, and the tramper bulk carrier capacity of 103~104% of the Panamax has been in the ports due to congestion. Earnings across the bulker segments have risen to ten-year highs in recent months. In this study, as factors affecting BDI, the capacity and congestion ratio of Cape and Panamax ships on the supply side, iron ore and coal seaborne tonnge on the demand side and Granger causality test, IRF(Impulse Response Function) and FEVD(Forecast Error Variance Decomposition) were performed using VAR model to analyze the impact on BDI by congestion caused by strengthen quarantine at the port due to the COVID-19 pandemic and the loading and discharging operation delay due to the infection of the stevedore, etc and to predict the shipping market after the pandemic. As a result of the Granger causality test of variables and BDI using time series data from January 2016 to July 2021, causality was found in the Fleet and Congestion variables, and as a result of the Impulse Response Function, Congestion variable was found to have significant at both upper and lower limit of the confidence interval. As a result of the Forecast Error Variance Decomposition, Congestion variable showed an explanatory power upto 25% for the change in BDI. If the congestion in ports decreases after With Corona, it is expected that there is down-risk in the shipping market. The COVID-19 pandemic occurred not from economic factors but from an ecological factor by the pandemic is different from the past economic crisis. It is necessary to analyze from a different point of view than the past economic crisis. This study has meaningful to analyze the causality and explanatory power of Congestion factor by pandemic.

• Journal of Popular Narrative
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• v.27 no.2
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• pp.215-262
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• 2021

This thesis focuses on Wandeuki and Elegant Lies - novels written by Kim Ryeo-reong and adapted into the film by Director Lee Han; this thesis analyzes the process of storytelling being transformed as the media is converted. Also, this thesis discusses cultural-political implications of transmedia storytelling where different narrative responses coexist concerning post-IMF family disorganization and "individualization." First of all, this thesis critically reviews existing discourses on the concept of transmedia storytelling and refers to 'transfictionality' the narratological concept of Marie-Laure Ryan in order to look into media conversion storytelling that starts from original novels. The novels Wandeuki and Elegant Lies show two aspects of "individualization" that adopts existential conditions of family disorganization. Wandeuki deviates from patriarchal family romance through self-discovery and exhibits loose family bond, which is something similar to companionship of close individuals. Elegant Lies shows individualization of pain by portraying a teenager who found herself completely isolated, while showing that it is impossible for the people left behind to mourn. On the other hand, director Lee Han's films and show stories in which family members, who are confronting family dissolution, rediscover and restore their families against family dissolution. The film promotes the expansion of family community through multicultural identity, and the film completes condolence of the people left behind by having the remaining families survive as survivors of suicide. The storyworld of the novels puts emphasis on 'self-discovery' of individual adolescents, while the storyworld of the movies puts emphasis on 'rediscovery of family'. Through transformation of storytelling - especially the redesigning of narrative structures called "modification" - transmedia storytelling shows that the relationship between media-converted texts is far from "faithful representation," but rather, shows conflicting themes and perspectives. With a reference point of 'the emergence of character' transmedia storytelling, which is predicated on the original work but aims to free itself from the original work by transforming storytelling through media conversion, opens up polyphonic storyworld by creating heterogeneous voices. In the post IMF-era, where uncertainty mounts over family dissolution and individualization, polyphonic storyworld created by transmedia storytelling provides an opportunity to experience disparate desires over individual freedom/risk and complacency toward community. We can call this the cultural-political implication of transmedia storytelling based on transferring, transcednding, and transforming.

• Journal of Korea Entertainment Industry Association
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• v.14 no.3
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• pp.27-40
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• 2020

The marathon has long been established as a representative lifestyle for all ages. With the recent expansion of the Work and Life Balance trend across the society, marathon with a relatively low barrier to entry is gaining popularity among young people in their 20s and 30s. By analyzing the issues and related words of the marathon event, we will analyze the spottainment elements of the marathon event that is popular among young people through keywords, and suggest a development plan for the differentiated event. In order to analyze keywords and related words, blogs, cafes and news provided by Naver and Daum were selected as analysis channels, and 'JTBC Marathon' and 'Culture' were extracted as key words for data search. The data analysis period was limited to a three-month period from August 13, 2019 to November 13, 2019, when the application for participation in the 2019 JTBC Marathon was started. For data collection and analysis, frequency and matrix data were extracted through social matrix program Textom. In addition, the degree of the relationship was quantified by analyzing the connection structure and the centrality of the degree of connection between the words. Although the marathon is a personal movement, young people share a common denominator of "running" and form a new cultural group called "running crew" with other young people. Through this, it was found that a marathon competition culture was formed as a festival venue where people could train together, participate together, and escape from the image of a marathon run alone and fight with themselves.

• Korean Journal of Poultry Science
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• v.48 no.4
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• pp.267-275
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• 2021

The aim of this study was to analyze the effect of dietary supplementation with ginseng berry, stems, and leaves on the growth performance, organ development, and blood biochemical characteristics of broilers. One hundred twenty one-day-old male broiler chicks (Ross 308) were randomly allocated to five groups: control (CON), ginseng berry 0.5% (GB1), ginseng berry 1.0% (GB2), ginseng stems and leaves 0.5% (GLS1), and ginseng stems and leaves 1.0% (GLS2). During the grower period (1-21 d), the body weight gain of all ginseng by-product fed groups was significantly higher (p<0.05) than that of the control group. During the finisher period (22-35 d), the feed intake in GLS2 was significantly higher (p<0.05) than that in the other groups, but there was no significant difference in weight gain or feed conversion ratio. No significant differences were detected among treatments when the growth performance was analyzed throughout the entire period (1-35 d). There was no significant difference in the serum biochemical profile, except for blood glucose. Glucose levels were significantly lower (p<0.05) in GLS groups, and tended to be lower in GB groups when compared to the control. Major organ weights showed no significant differences among treatment groups when compared to each other. In conclusion, dietary supplementation of ginseng by-products may improve the early growth of broiler chickens and reduce blood glucose levels.

• Korean Journal of Psychosomatic Medicine
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• v.30 no.2
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• pp.155-164
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• 2022

Objectives : A growing body of evidence links type 2 diabetes (T2D) with a neurodegenerative disease (ND) such as Alzheimer's disease and Parkinson's disease. The purpose of this study is to investigate the relationship between NDs and the development of T2D by comparing the incidence of T2D in a group of various NDs (ND group) and control group. Methods : A population-based 10-year follow-up study was conducted using the Korean National Health Information Database for 2002-2015. We used a retrospective cohort study design to investigate the association of ND with T2D occurrence. The study population included ND (n=8,814) and control (n=37,970) groups, all aged 60 years or over. The Kaplan-Meier method was used to estimate the risk of developing T2D as a function of time. Cox proportional hazards regression models were used to evaluate the relationship between ND and T2D. Results : T2D was developed in a significantly higher percentage of patients in the ND group (53.6%) than in the control group (44.7%). The ND group increased the risk of T2D (HR, 1.43; 95% CI, 1.38-1.47). About one-third of patients in both groups were additionally diagnosed with another ND before the occurrence of T2D during a 10-year follow-up period. When compared to those who did not have another ND during the follow-up period, the incidence of T2D in those who were additionally diagnosed with another ND was higher in both the ND and control groups. Conclusions : The ND group had about 1.4 times higher risk of developing T2D than the control group. Our results showed a positive association between ND and T2D.

• Journal of the Korean Society of Radiology
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• v.16 no.1
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• pp.35-43
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• 2022

In this study, a survey was conducted and analyzed to find out the satisfaction of online classes among students enrolled in the radiology department of a university located in Busan city. As a result, in terms of satisfaction with online classes, male scores were higher, but there was no statistically significant difference. In the interdisciplinary system, the satisfaction score of the students enrolled in Bachelor's degree was high, and there was a statistically significant difference except for the satisfaction of learning participation (p<0.001, p<0.05). For class satisfaction by grade level, Senior had higher scores, and there were statistically significant differences except for learning participation satisfaction (p<0.001, p<0.01, p<0.05). In the satisfaction survey according to the number of lectures, the scores of the students who took 4-7 lectures were found to be high except for the satisfaction of learning participation, and there was a statistically significant difference (p<0.01, p<0.05). In the method of communication with the instructor, students who used e-mail showed high scores, and there was a statistically significant difference in lecture satisfaction (p<0.05). In the correlation analysis between sub-variables for online classes, statistically significant correlations were established in all areas. Most of the students preferred class methods such as recorded classes and classes using external content such as YouTube, and when asked about the merits of online classes, many students answered that the advantages of online classes were repetitive classes and no restrictions on time and place. When asked about the shortcomings of online classes, many students answered that it was a lack of concentration and lack of communication with the instructor. This study was conducted to provide basic data to improve the satisfaction of online classes that will increase in the future. Therefore, based on the results of this study, it is expected that more quality online classes will be produced so that students' satisfaction with online classes can be improved.