• Korean Journal of Heritage: History & Science
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• v.40
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• pp.137-167
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• 2007

This paper is aimed to study the late Neolithic Age in North Korea in order to closely examine a transition process into the Bronze Age in the Korean peninsula. Thus, the pottery with lightning design was selected as target data. Since the pottery with lightning design is fundamental data that North Korea's archeologists have used for chronological recordings of the late Neolithic Age in the northwest region, the parallel relationship between the eastern and the western region was established with comparison of pottery with lightning design in the northeastern region. The examination focuses on data that cover the target region of the pottery with lightning design of the adjacent Southern Primorskii region including the counterpart of the northwestern and the northeastern region. As a result, some attribute analyses revealed that the pottery with lightning design was affected by the counterpart of the northwestern region near the Yalu River. Prior to genealogical and chronological recordings of the pottery with lightning design in the northeastern region, the pottery with lightning design in the northwestern region was recorded chronologically in order to examine its specific development process. Consequently, in the second period of the Neolithic Age, the pottery with lightning design in the northwestern region was assumed to have an impact on the counterpart in the northeastern region. The classification of the pottery with lightning design in the northeastern region shall be based on 4-period development. According to this classification, the pottery, which was found in the Tumen river basin, was thought to belong to the first period. The pottery went through genealogy differentiation in the second period and when entering into the third period, the pottery spread to inland of south Primorskii. The pottery was assumed to exist in the southern Primorskii region until the tip end (the fourth period) of the Neolithic Age. It is assumed that considering the fact that climate change led to the agriculture movement, Zaisanovka culture, i.e. the late Ne Neolithic Age, moved to the southern Primorskii region along the Tumen River basin.

• Journal of The Korean Society of Emergency Medicine
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• v.29 no.5
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• pp.493-499
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• 2018

Objective: This study aimed to identify the effects of serum potassium and lactate on neurologic outcomes in out-of-hospital post-cardiac arrest adult patients. Methods: This study was a single center, retrospective observational study. We recruited out-of-hospital post-cardiac arrest adult patients admitted to an intensive care unit from 2011 to 2017. Primary outcome was good neurologic outcome at discharge. To evaluate the prognostic impact of serum potassium and lactate, univariate and multivariate logistic regression analyses were performed. Results: A total of 57 patients were included in this study. The number of patients with good neurologic outcome was 19 (33.3%). In the univariate analysis, good neurologic outcome patients showed a higher smoking rate, shorter pre-hospital transportation time, higher rate of percutaneous coronary intervention, and lower severity score (all P<0.05). The good neurologic outcome patients also presented higher pH, lower partial pressure of carbon dioxide, and lower potassium regarding laboratory findings on the first hospital day (all P<0.05). In the multivariate analysis, the independent factors favoring good neurologic outcome were pre-hospital transportation time (adjusted odds ratio [aOR], 0.82; 95% confidence interval [CI], 0.69-0.97; P=0.019) and lower partial pressure of carbon dioxide on the first hospital day (aOR, 0.95; 95% CI, 0.91-0.99; P=0.034). Conclusion: Serum potassium and lactate were not significantly associated with good neurologic outcome in out-of-hospital post-cardiac arrest adult patients. The prognostic factors for good neurologic outcome were pre-hospital transportation time and initial partial pressure of carbon dioxide.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.6
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• pp.275-282
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• 2021

High-molecular-weight maleic anhydride-grafted polylactic acids (HMMA-g-PLA) compatibilizers were prepared by melt grafting in a twin screw extruder using di(tert-butyl-perxoyisopropyl)benzene (PK-14; as initiator), maleic anhydride (MA), and divinylbenzene (DVB). To determine the properties of the prepared HMMA-g-PLA compatibilizers, Fourier transform infrared (FTIR), Melt index (MI), and back-titration analyses were performed. On increasing DVB concentration, grafting yield of HMMA-g-PLA increased but MI decreased because 𝛽-scission of PLA was restrained by the DVB, and thus, the molecular weight of HMMA-g-PLA increased. PLA-based wood-plastic composites (WPCs) were prepared using HMMA-g-PLA by melt blending through a single screw extruder. The flexural and impact strengths of WPCs compatibilized with HMMA-g-PLA were greater than those of WPCs produced without HMMA-g-PLA. Scanning electron microscope (SEM) studies indicated that increased mechanical properties were caused by excellent interfacial adhesion between PLA and wood fibers due to the addition of HMMA-g-PLA. However, rather high contents of HMMA-g-PLA reduced the mechanical properties of WPCs. We believe that lower molecular-weight of HMMA-g-PLA added as an compatibilizer, compared with PLA polymer, caused the reduction of mechanical properties.

• The Journal of the Korea Contents Association
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• v.20 no.12
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• pp.58-73
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• 2020

The purpose of this study is to empirically analyze the relationship between organizational commitment, job satisfaction, education and training, human resource development, and communication in Korea's financial industry. In particular, the mediating relationships between organizational commitment and job satisfaction, education and training, human resource development, and communication were examined in order to provide a better understanding of organizational commitment. A structural equation model was used for the empirical analysis of this study. As a result of the study, it was confirmed that education and training, human resource development, communication, organizational commitment, and job satisfaction are correlated within the Korean financial industry. Furthermore, organizational commitment was found to have mediating effects on education and training, human resource development, communication, and job satisfaction. Based on these results, this study emphasizes the importance of education and training for organizational commitment in the Korean financial industry. In particular, this study establishes the importance of a culture of trust within organizations through human resource development programs, communication for job satisfaction, and organizational performance to face changes in the post-COVID era. In the future, more in-depth qualitative studies are required to derive factors related to the employees of financial companies and to conduct comparison analyses with companies in other industries.

• Journal of Digital Convergence
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• v.18 no.12
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• pp.425-434
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• 2020

Background: Viral infection outbreaks are emerging public health concerns. They often exhibit seasonal patterns that could be predicted by the application of big data and bioinformatic analyses. Purpose: The purpose of this study was to identify trends in diarrhea-causing viruses such as rotavirus (Gr.A), norovirus G-I, and norovirus G-II in Cheonan, Korea. The identified related factors of diarrhea-causing viruses may be used to predict their trend and prevent their infections. Method: A retrospective analysis of 4,009 fecal samples from June 2010 to December 2019 was carried out at Dankook University Hospital in Cheonan. Reverse transcription-PCR (RT-PCR) was employed to identify virus strains. Information about seasonal patterns of infection was extracted and compared with local weather data. Results: Out of the 4,009 fecal samples tested using multiplex RT-PCR (mRT-PCR), 985 were positive for infection with Gr.A, G-I, and G-II. Out of these 985 cases, 95.3% (n = 939) were under 10 years of age. Gr.A, G-I, and G-II showed high infection rates in patients under 10 years of age. Student's t-test showed a significant correlation between the detection rate of Gr.A and the relative humidity. The detection rate of G-II significantly correlated with wind-chill temperature. Conclusion: Climate factors differentially modulate rotavirus and norovirus infection patterns. These observations provide novel insights into the seasonal impact on the pathogenesis of Gr.A, G-I, and G-II.

• Journal of Korean Neurosurgical Society
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• v.64 no.4
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• pp.644-664
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• 2021

Objective : Since the enactment of the Special Act on Korean Medical Residents, neurosurgeons working at training hospitals have been performing the duties of residents, in addition to their existing patient care responsibilities, which include surgery, education, and research. This study explores the relationships between work intensity, work-life balance, and burnout experienced by Korean neurosurgeons. Methods : The participants (n=451) were neurosurgeons working at training hospitals throughout Republic of Korea. Data on socio-demographic characteristics (including objective and subjective work environment), work intensity, work-life balance, and burnout were gathered using self-report questionnaires completed between March 1 and December 20, 2019. The data were analyzed using descriptive statistics, independent samples t-tests, one-way analysis of variance, Pearson's correlations, and multiple regression analysis. IBM SPSS Statistics for Windows, version 25 (IBM Corp., Armonk, NY, USA) was used for the analyses. Results : The work intensity, work-life balance, and burnout levels of neurosurgeons were 3.95, 3.57 (on a scale from 1 to 5) and 4.60 (on a scale from 1 to 7); and 280 (62.1%) of 451 neurosurgeons were found to be experiencing burnout. By controlling for the socio-demographic characteristics, the effects of work intensity and work-life balance on burnout were analyzed. Work intensity (B=0.314), work-life balance-family and leisure (B=0.216), work-life balance-growth (B=0.147), job stress (B=0.133), and satisfaction with human relationships (B=-0.069) were shown to be significant (all p<0.05), and they were found to affect burnout in the abovementioned order. The overall explanatory power was 58.3% (p<0.05), and the explanatory power with the addition of independent variables such as work intensity and work-life balance was 14.5% (p<0.05). Conclusion : This study showed that Korean neurosurgeons working at training hospitals experienced a high level of work intensity and job stress, and low work-life balance. Additionally, nearly half of the neurosurgeons were found to experience burnout related to factors such as work intensity, work-life balance, job stress, and satisfaction with human relationships. In particular, these factors seem to have deteriorated further after the implementation of the Special Act on Korean Medical Residents. These very high levels of burnout among Korean neurosurgeons who care for patients with both brain and spinal diseases may have a very important impact on patients' health. Therefore, it is recommended that the Korean Neurosurgical Society and the Korean government make efforts to improve the factors that affect burnout among Korean neurosurgeons.

• Korean Journal of Psychosomatic Medicine
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• v.28 no.2
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• pp.168-176
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• 2020

Objectives : Loneliness and poor sleep quality are common phenomena in old age and are associated with negative physical and mental health. However, little is known regarding the relation between loneliness and sleep quality. The aim of this study was to examine the association of loneliness and sleep quality among the elderly living alone. Methods : This is a cross-sectional study that enrolled 1,090 subjects who are the community-residing elderly living alone. Sociodemographic status, medical condition, cognition, mood disorder, sleep quality and levels of loneliness were collected using a self-administered questionnaire and a specific semi-structured interview conducted by trained nurses. Descriptive statistics were used to analyze data regarding sociodemographic variable and loneliness. Univariate and Multivariate regression analyses were applied to examine the association between loneliness and sleep quality after adjustment for multiple confounding variables. Results : The Pittsburgh Sleep Quality Index (PSQI) mean score of "lonely group" (9.2±4.2) was significantly higher than that of "not lonely group" (7.3±3.7) (student-t test, p<0.001). Loneliness was significantly associated with PSQI (standardized β=0.065, p=0.025), sleep disturbance (standardized β=0.086, p=0.005), use of sleep medication (standardized β=0.065, p=0.034) after adjustment for possible confounding variables including sex and mood disorder. Conclusions : Loneliness was associated with sleep disturbance and this finding implied negative impact of loneliness on sleep quality of older adults. Public health promotion efforts to reduce loneliness may improve sleep quality and mental health in the elderly living alone.

• Knowledge Management Research
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• v.22 no.4
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• pp.157-172
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• 2021

Information security companies were established in earnest from the mid-late 1990s to early 2000s, far shorter than other national key industries. Nevertheless, the information security industry has made rapid progress. It is expected that the proportion of the information security industry will increase rapidly with the development of advanced technology along with the 4th industrial revolution. As COVID-19, which occurred at the end of 2019, spreads around the world in 2020, non-face-to-face services and digital transformation are accelerating, and cyber threats to users are also increasing. However, there are limitations in responding to new Cyber Security threats due to the shortage of information protection manpower, insufficient security capabilities of domestic companies, and the narrow domestic information protection market. This study examines the external environmental factors of information security companies such as government information protection system operation, government influence, government support, partnership between information security companies, and internal environmental factors such as top management support, financial status, human resources, organizational capability, This study was conducted using empirical data to analyze whether it affects innovation capability and whether organizational capability and innovation capability affect financial and non-financial performance. The results of this study can be used as basic data to suggest policies and implications for information security, and to strengthen the competitiveness of the information security industry.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.5
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• pp.207-220
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• 2021

This study aimed to evaluate the impact of education and counselling by nurses on anxiety, uncertainty, and pain in patients with benign uterine tumors. Electronic databases, including PubMed, OVID, CINAHL, Google Scholar, and Korean databases and were searched during January 2020. A total of 401 studies were identified of which 13 were suitable for meta-analysis. Cochrane's risk of bias tool and the R version 3.5.2 (Meta-analysis with R) program were used for analysis. The authors performed a meta-analysis of the 13 trials that met eligibility criteria. The findings in this study indicate that the effect size of nursing education for anxiety was Hedges' g=-0.89 (95% CI:-1.39 to -0.47), as indicated by a "large effect size" and the effect size of pain was Hedges' g=-0.49 (95% CI:-0.95 to -0.02) as indicated by a "moderate effect size". The effect size of uncertainty was Hedges' g=-1.38 (95% CI:-3.98 to 1.23), and it was not statistically significant. In the meta-subgroup analyses by approach intervention type, cognitive-behavioral programs, demonstration intervention, and relaxation therapy had a significant effect. The risk of publication bias was low. It may therefore be concluded that pre-operative education by nurses for patients with benign uterine tumors would affect their levels of anxiety, uncertainty, and pain.

• Journal of Korea Trade
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• v.26 no.2
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• pp.45-64
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• 2022

Purpose - This paper examines South Korea's potential status as a carbon leakage country, and the level of risk posed by the Korean emissions trading scheme (ETS) for Korean industries. The economic effects of border carbon adjustments (BCAs) to protect energy-intensive Korean industries in the process of achieving the carbon reduction target by 2030 through the Korean ETS are also analyzed. Design/methodology - First, using the Korean Input-Output (IO) table, this paper calculates the balance of emissions embodied in trade (BEET) and the pollution terms of trade (PTT) to determine Korean industries' carbon leakage status. Analyses of the risk level posed by carbon reduction policy implementation in international trade are conducted for some sectors by applying the EU criteria. Second, using a computable general equilibrium (CGE) model, three BCA scenarios, exemption regulations (EXE), reimbursement (REB), and tariff reduction (TAR) to protect the energy-intensive industries under the Korean ETS are addressed. Compared to the baseline scenario of achieving carbon reduction targets by 2030, the effects of BCAs on welfare, carbon leakage, outputs, and trading are analyzed. Findings - As Korea's industrial structure has been transitioning from a carbon importing to a carbon leaking country. The results indicate that some industrial sectors could face the risk of losing international competitiveness due to the Korean ETS. South Korea's industries are basically exposed to risk of carbon leakage because most industries have a trade intensity higher than 30%. This could be interpreted as disproving vulnerability to carbon leakage. Although the petroleum and coal sector is not in carbon leakage, according to BEET and PTT, the Korean ETS exposes this sector to a high risk of carbon leakage. Non-metallic minerals and iron and steel sectors are also exposed to a high risk of carbon leakage due to the increased burden of carbon reduction costs embodied in the Korean ETS, despite relatively low levels of trade intensity. BCAs are demonstrated to have an influential role in protecting energy-intensive industries while achieving the carbon reduction target by 2030. The EXE scenario has the greatest impact on mitigation of welfare losses and carbon leakage, and the TAF scenario causes a disturbance in the international trade market because of the pricing adjustment system. In reality, the EXE scenario, which implies completely exempting energy-intensive industries, could be difficult to implement due to various practical constraints, such as equity and reduction targets and other industries; therefore, the REB scenario presents the most realistic approach and appears to have an effect that could compensate for the burden of economic activities and emissions regulations in these industries. Originality/value - This paper confirms the vulnerability of the Korean industrial the risk of carbon leakage, demonstrating that some industrial sectors could be exposed to losing international competitiveness by implementing carbon reduction policies such as the Korean ETS. The contribution of this paper is the identification of proposed approaches to protect Korean industries in the process of achieving the 2030 reduction target by analyzing the effects of BCA scenarios using a CGE model.