• Journal of Industrial Convergence
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• v.20 no.11
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• pp.135-140
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• 2022

A study to estimate the appropriate size for the quota of civil servants during the period of change of government is required. Therefore, in this study, we would like to introduce a study that uses DEA to estimate the appropriate size of public officials. The department of a public institution is DMU, and the number of employees in each department is applied as an input variable, and the number of electronic approval production documents and the number of electronic approval expenditures are applied as output variables. MaxDEA 8 was used as an analysis program for this purpose. As a result of the analysis, when the efficiency level was 1.00 (100%), 3 out of 14 departments showed the optimal level by satisfying the efficiency, and 10 of the remaining departments scored 0.50 (50%) with a score of 0.50 (50%), confirmed to be relatively inefficient. In other words, it was confirmed that most departments had inefficient surplus staff. As an additional analysis, we calculated the number of possible staff reductions using the efficiency level. Using this, it is expected that the field of manpower reduction can be discovered in advance through an analysis of manpower efficiency by department, and based on this, it can be used to relocate manpower by department according to future response strategies.

• Journal of Industrial Convergence
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• v.20 no.11
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• pp.65-74
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• 2022

This study was attempted to determine the degree of self-determination motivation, interpersonal relationship harmony, and academic self-efficacy of freshmen admitted to the nursing department during the COVID-19 period, and to identify factors affecting academic self-efficacy. Data were collected from November 01 to November 30, 2021, and the subjects of this study were 220 freshmen enrolled in the Department of Nursing at a university located in C city. For data analysis, t-test, anova and scheffé's post hoc test, pearson correlation coefficients calculation and multiple regression analysis were performed using SPSS 25.0. As a result of the study, it was found that face-to-face learning experience in the first semester, the reason for choosing a major, self-determination motivation and interpersonal relationship harmony explained 47.9% of the total change in academic self-efficacy. And it was found that freshmen with face-to-face learning in the first semester, self-determination motivation and interpersonal harmony had a significant effect on academic self-efficacy. In order to improve the academic self-efficacy of the first year, a program to support self-determination motivation and harmonize interpersonal relationships should be developed and applied.

• Korean journal of applied entomology
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• v.61 no.4
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• pp.577-590
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• 2022

Ostrinia scapulalis is one of important pests in leguminous crops, especially red bean. In order to understand the biological characteristics of the insect, we investigated the effects of temperature on development of each life stage, adult longevity and fecundity of O. scapulalis at eleven constant temperatures of 7, 10, 13, 16, 19, 22, 25, 28, 31, 34, and 36℃. Eggs and larvae successfully developed next life stage at most temperature subjected except 7, 10 and 13℃. The developmental period of egg, larva and pupa decreased as temperature increased. Lower and higher threshold temperature (TL and TH) were calculated by the Lobry-Rosso-Flandrois (LRF) and Sharpe-Schoolfield-Ikemoto (SSI) models. The lower developmental threshold (LDT) and thermal constant (K) from egg hatching to adult emergence of O. scapulalis were estimated by linear regression as 13.5℃ and 384.5DD, respectively. TL and TH from egg hatching to adult emergence using SSI model were 19.4℃ and 39.8℃. Thermal windows, i.e., the range in temperature between the minimum and maximum rate of development, of O. scapulalis was 20.4℃. Adults produced viable eggs at the temperature range between 16℃ and 34℃, and showed a maximum number, ca. 416 offsprings, at 25℃. Adult models including aging rate, age-specific survival rate, age-specific cumulative oviposition, and temperature-dependent fecundity were constructed, using the temperature-dependent adult traits. Temperature-dependent development models and adult oviposition models will be useful components to understand the population dynamics of O. scapulalis and will be expected using a basic data for establishing the strategy of integrated pest management in leguminous crops.

• Korean journal of applied entomology
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• v.61 no.3
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• pp.435-447
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• 2022

The soybean podborer, Matsumuraeses falcana (Lepidoptera: Tortricidae), is one of important pests in soybean crop. In the purpose of forecasting population dynamics of M. falcana, we investigated the effects of temperature on development of each life stage, adult longevity and fecundity of Matsumuraeses falcana at seven constant temperatures of 10, 13, 19, 22, 25, 28, and 31℃. Eggs hatched successfully at all temperature subjected. M. falcana developed from egg hatching to adult emergence at the tested temperatures except 10, 13, and 31℃. The developmental period of each life stage and adult longevity of M. falcana decreased as temperature increased. The lower developmental threshold (LDT) and thermal constant (K) from egg hatching to adult emergence of M. falcana were estimated by linear regression as 10.2℃ and 492.04DD, respectively. Lower and higher threshold temperature (TL and TH) were calculated by the Lobry-Rosso-Flandrois (LRF) and Sharpe-Schoolfield-Ikemoto (SSI) models. TL and TH from egg hatching to adult emergence using SSI model were 16.7℃ and 29.1℃. Thermal windows, i.e., the range in temperature between the minimum and maximum rate of development, of M. falcana was 12.4℃. We constructed the adult oviposition model of M. falcana using adult survivorship and fecundity. Temperature-dependent immature development and adult oviposition models will help constructing the population model of M. falcana and developing the strategies of integrated pest management in soybean fields.

• Korean journal of applied entomology
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• v.61 no.3
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• pp.461-473
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• 2022

Matsumuraeses phaseoli is one of important pests in soybean crops, especially adzuki beans. We investigated the effects of temperature on development of each life stage, adult longevity and fecundity of M. phaseoli for understanding the biological characteristics of M. phaseoli at ten constant temperatures of 7, 10, 13, 16, 19, 22, 25, 28, 31, and 34℃. Eggs hatched successfully at all temperature subjected except 7℃ and 34℃. The developmental period of each life stage and adult longevity of M. phaseoli decreased as temperature increased. Lower and higher threshold temperature (TL and TH) were calculated by the Lobry-Rosso-Flandrois (LRF) and Sharpe-Schoolfield-Ikemoto (SSI) models. The lower developmental threshold (LDT) and thermal constant (K) from egg hatching to adult emergence of M. phaseoli were estimated by linear regression as 9.04℃ and 422.97DD, respectively. TL and TH from egg hatching to adult emergence using SSI model were 20.0℃ and 32.3℃. Thermal windows, i.e., the range in temperature between the minimum and maximum rate of development, of M. phaseoli was 12.3℃. We constructed the adult oviposition model of M. phaseoli using adult survivorship and fecundity. Temperature-dependent development models and adult oviposition models will be helpful to understand the population dynamics of M. falcana and to establish the strategy of integrated pest management in soybean fields.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.19 no.2
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• pp.8-19
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• 2023

Hydronic heated road pavement (HHP) systems have well studied and documented by many researchers. However, most of the systems run on asphalt, only a few are tested with concrete, and there rarely is a comparison between those two common road materials in their heating and cooling performance. The aim of this study is to investigate the thermal performance of the HHP, such as heat dissipation performance in winter season while focusing on the surface temperature of the concrete and asphalt pavement. For preliminary study a small-scale experimental system was designed and installed to evaluate the heat transfer characteristics of the HHP in the test field. The system consists of concrete and asphalt slabs made of 1 m in width, 1 m in length, and 0.25 m in height. In two slabs, circulating water piping was embedded at a depth of 0.12 m at intervals of 0.16 m. Heating performance in winter season was tested with different inlet temperatures of 25℃, 30℃, 35℃ and 40℃ during the entire measurement period. The results indicated that concrete's heating performance is better than that of asphalt, showing higher surface temperatures for the whole experiment cases. However, the surface temperature of both concrete and asphalt pavement slabs remained above 0℃ for all experimental conditions. The heat dissipation performance of concrete and asphalt pavements was analyzed, and the heat dissipation of concrete pavement was greater than that of asphalt. In addition, the higher the set temperature of the circulating water, the higher the heat dissipation. On the other hand, the concrete pavement clearly showed a decrease in heat dissipation as the circulating water set temperature decreased, but the decrease was relatively small for the asphalt pavement. Based on this experiment, it is considered that a circulating water temperature of 20℃ or less is sufficient to prevent road ice. However, this needs to be verified by further experiments or computational fluid dynamic (CFD) analysis.

• Journal of Korea Water Resources Association
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• v.56 no.9
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• pp.529-541
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• 2023

Due to the growing concern over forecasting extreme weather events such as droughts caused by climate change, there has been a rising interest in seasonal meteorological forecasts that offer ensemble predictions for the upcoming seven months. Nonetheless, limited research has been conducted in South Korea, particularly in assessing their effectiveness at the catchment-scale. In this study, we assessed the accuracy of ECMWF's seasonal forecasts (including precipitation, temperature, and evapotranspiration) for the period of 2011 to 2020. We focused on 12 multi-purpose reservoir catchments and compared the forecasts to climatology data. Continuous Ranked Probability Skill Score method is adopted to assess the forecast skill, and the linear scaling method was applied to evaluate its impact. The results showed that while the seasonal meteorological forecasts have similar skill to climatology for one month ahead, the skill decreased significantly as the forecast lead time increased. Compared to the climatology, better results were obtained in the Wet season than the Dry season. In particular, during the Wet seasons of the dry years (2015, 2017), the seasonal meteorological forecasts showed the highest skill for all lead times.

• Journal of Korea Water Resources Association
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• v.56 no.9
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• pp.563-574
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• 2023

Recently, climate change has affected functional responses of river basins to meteorological variables, emphasizing the importance of rainfall-runoff simulation research. Simultaneously, the growing interest in machine learning has led to its increased application in hydrological studies. However, it is not yet clear whether machine learning models are more advantageous than the conventional conceptual models. In this study, we compared the performance of the conventional GR6J model with the machine learning-based Random Forest model across 38 basins in Korea using both gauged and ungauged basin prediction methods. For gauged basin predictions, each model was calibrated or trained using observed daily runoff data, and their performance was evaluted over a separate validation period. Subsequently, ungauged basin simulations were evaluated using proximity-based parameter regionalization with Leave-One-Out Cross-Validation (LOOCV). In gauged basins, the Random Forest consistently outperformed the GR6J, exhibiting superiority across basins regardless of whether they had strong or weak rainfall-runoff correlations. This suggest that the inherent data-driven training structures of machine learning models, in contrast to the conceptual models, offer distinct advantages in data-rich scenarios. However, the advantages of the machine-learning algorithm were not replicated in ungauged basin predictions, resulting in a lower performance than that of the GR6J. In conclusion, this study suggests that while the Random Forest model showed enhanced performance in trained locations, the existing GR6J model may be a better choice for prediction in ungagued basins.

• Journal of the Korean Society for information Management
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• v.40 no.3
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• pp.119-142
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• 2023

Copyright is a legal criterion for determining the scope and method of digital library service. Works with expired protection periods correspond to the public domain and can be freely used by anyone. For this reason, it is a priority consideration in digital library construction and services. The purpose of this study is to examine how actively libraries are using expired protected works for digital library services. To this end, the relevant provisions of the Copyright Act applied to the construction and service of digital libraries were first summarized, and the meaning of the copyright protection period was theoretically examined. The current status of online services for expired works by the National Library of Korea was examined, focusing on the works of three Japanese colonial era writers, Kim Yoo-jung, Lee Hyo-seok, and Chae Man-sik, to check the specific service status of expired works. It reveals that the National Library of Korea is not fully utilizing the scope of the law, and that this situation is linked to the rights of other authors included in the book. Based on these results, it suggests that there is a need to change the service unit to focus on copyrighted works and to use authority records to systematize the management of authors' death years.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.34 no.3
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• pp.135-161
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• 2023

This study analyzed the research trends of COVID-19 research papers published in medical journals of Korea. Data were collected from 25 MEDLINE journals in 'Medicine and Pharmacy' studies and a total of 800 were selected. As a result of the study, authors from domestic affiliations made up 76.96% of the total, and the proportion of authors from foreign institutions decreased without significant change. The authors' majors were 'Internal Medicine' (32.85%), 'Preventive Medicine/Occupational and Environmental Medicine' (16.23%), 'Radiology' (5.74%), and 'Pediatrics' (5.50%), and 435 (54.38%) papers were collaborative research. As for author keywords, 'COVID19' (674), 'SARSCoV2' (245), 'Coronavirus' (81), and 'Vaccine' (80) were derived as top keywords. There were six words that appeared throughout the entire period: 'COVID19,' 'SARSCoV2,' 'Coronavirus,' 'Korea,' 'Pandemic,' and 'Mortality.' Co-occurrence network analysis was conducted on MeSH terms and author keywords, and common keywords such as 'covid-19,' 'sars-cov-2,' and 'public health' were derived. In topic modeling, five topics were identified, including 'Vaccination,' 'COVID-19 outbreak status,' 'Omicron variant,' 'Mental health, control measures,' and 'Transmission and control in Korea.' Through this study, it was possible to identify the research areas and major keywords by year of COVID-19 research papers published during the 'Public Health Emergency of International Concern (PHEIC).'