• Journal of the Korea Society of Computer and Information
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• v.26 no.10
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• pp.179-184
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• 2021

In this paper, we propose the deep learning-based neural network model to predict bunker price. In the shipping industry, since fuel oil accounts for the largest portion of ship operation costs and its price is highly volatile, so companies can secure market competitiveness by making fuel oil purchasing decisions based on rational and scientific method. In this paper, short-term predictive analysis of HSFO 380CST in Singapore is conducted by using three recurrent neural network models like RNN, LSTM, and GRU. As a result, first, the forecasting performance of RNN models is better than LSTM and GRUs using long-term memory, and thus the predictive contribution of long-term information is low. Second, since the predictive performance of recurrent neural network models is superior to the previous studies using econometric models, it is confirmed that the recurrent neural network models should consider nonlinear properties of bunker price. The result of this paper will be helpful to improve the decision quality of bunker purchasing.

• The Journal of the Korea Contents Association
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• v.19 no.3
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• pp.261-274
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• 2019

This paper aims to develop an appropriate methodology for establishing an investment strategy for 'demonstration of artificial rainfall technology using UAV' and that include establishment of a technology classification, set of indicators for technology evaluation, suggestion of final key technology as a whole study area. It is designed to complement the latest research trend analysis results and expert committee opinions using quantitative analysis. The key indicators for technology evaluation consisted of three major items (activity, technology, marketability) and 10 detailed indicators. The AHP questionnaire was conducted to analyze the importance of indicators. As a result, it was analyzed that the attribute of the technology itself is most important, and the order of closeness to the implementation of the core function (centrality), feasibility (feasibility). Among the 16 technology groups, top investment priority groups were analyzed as ground seeding, artificial rainfall verification, spreading and diffusion of seeding material, artificial rainfall numerical modeling, and UAV sensor technology.

• Journal of Korean Library and Information Science Society
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• v.50 no.2
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• pp.191-214
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• 2019

In order to understand the trends of collaborative research in the field of Library and Information Science (LIS) in Korea, this study analyzed bibliometric data and keywords of 5,383 Journal papers by 195 Korean LIS professors from 2000 to 2017 as well as the author credit allocation formulas of 26 Korean university research evaluation criteria. Examination of university research evaluation criteria revealed co-authors' credit level to be generally much lower than that of single authors, which in turn reduces the relative value of collaborative research. As a result, recent journals publish more co-authored papers than single author papers both domestically and internationally. The study also found collaborative research to be less prevalent in private universities than national universities and least prevalent in associate professors among professors. Furthermore, keyword analysis of study data revealed the emerging topics of both domestic and international collaborative research to be those that reflect social phenomena as well as those that relate to information science employing new technologies.

• Journal of Korea Society of Industrial Information Systems
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• v.14 no.5
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• pp.281-288
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• 2009

The purpose of this paper is to provide the statistical models for landslide prediction through quantification and AHP methods. Quantification method is a statistical method of providing quantity to qualitative variables by analyzing the observed data. In this paper, we suggest the quantification process based on the results of cannonical correlation analysis. In contrast with the quantification method which is based on given data the AHP(Analytic Hierarchy Process) technique is a kind of method based on questionaire data which is usually taken from professionals. We analyze both the real data(provided from KIGAM) and questionaire data collected from professionals of various related area. We developed two kinds of evaluation table which provide the scores of land slide possibility and the logistic model providing the probability of occurring landslide. Finally we compare the performance and evaluate the stability of the suggested two models.

• Journal of the Korean Society for information Management
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• v.40 no.4
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• pp.375-401
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• 2023

A school library is where students develop their skills to cope with future uncertainty and can utilize various information materials to build their capability and response abilities to changes. Teachers' perception is crucial as their guidance is essential for the student to use the school library. Most studies, however, focused on quantitative measurement of the importance of the teachers' perception as an external environment, and there is a lack of specific categorization of different types of perceptions on the role of the school library. This study aims to examine types of perceptions about the school library among elementary school teachers. To do so, this study used Latent Profile Analysis (LPA), a person-centered approach, to identify teachers' complex perceptions about the role and importance of the school library, which were difficult to review in previous studies, and the teachers' most representative types of perceptions. Based on the findings from the above, this study is meaningful in proposing customized measures to operate and promote the school library depending on teachers' perceptions.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.6
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• pp.77-91
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• 2023

Recently, there has been a worldwide increase in research and development on automated vehicles for commercialization. It is expected that the use of level 3 autonomous vehicles on continuous-flow roads will be introduced and will increase. Consequently, various studies have been conducted to investigate the impact of mixed traffic flow with automated vehicles based on the market penetration rate (MPR). However, these studies have been conducted independently, and the results have shown different trends. Therefore, this study attempted a quantitative analysis of the impact of automated vehicles on mixed traffic flow on uninterrupted roads through a meta-analysis. The results showed that the effect size estimated from an MPR of 75% or higher was statistically significant.

• Analyses & Alternatives
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• v.7 no.1
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• pp.115-145
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• 2023

The 20th National Congress of the Chinese Communist Party (hereafter referred to as "the 20th National Congress") was under the global spotlight long before it was held for seven days from 16 to 22 October 2022. People wondered whether Xi Jinping would secure a third term as China's leader or whether he would lay the foundations to be in power forever during the third term. In Korea, the press and media questioned whether the event would become the "crowning of Emperor Xi (Xi Huangdi)," whose power rivaled that of the first emperor in China, Shi Hunagdi, and featured the scene where Hu Jintao was forced to leave the venue during the Congress. On the other hand, many Korean academics focused more on how Xi would organize the Politburo and its Standing Committee and whether the outline of his heirs would appear during the event. This tendency in academia in turn worsened the media's concerns. This paper presents a quantitative analysis of the 20th National Congress Report, as opposed to an analysis of Xi's political intentions at the event. The National Congress Report outlines the Party's visions, goals, and strategies for the next five years in politics, economy, society, culture, foreign affairs, and relationship with Taiwan. The authoritative document is rich in narrative and logic and deserves academic study. This research analyzes the 18th, 19th, and 20th Reports by identifying their keywords and regular expressions and checking their frequency and percentage through text-mining methods. This approach enables the quantification and visualization of the significant changes in the Party's sovereign vision over the fifteen years of Xi's rule from 2013 to 2027.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.848-852
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• 2012

Vegetation can make not only to lower the urban ambient air temperature (UAAT) by crop evapotranspiration (ET) and increasing solar radiation albedo, but also to reduce the urban air pollution by $CO_2$ uptake and $O_2$ emission in addition to the reducing ozone concentrations by aid of lower the UAAT. To evaluate the effect of vegetation on urban heat island mitigation (UHIM), the climate change of 6 cities during 30 years are analysed, and the amount of ET, $CO_2$ uptake, $O_2$ emission and ozone concentrations are estimated in Korea. The most hot season is the last part of July and the first part of August, and the highest average UAAT of a period of ten days was $35.03^{\circ}C$ during 30 years (1979 - 2008). The mean values of maximum ET of rice and soybean in urban area during urban heat island phenomena were 6.86 and $6.00mm\;day^{-1}$, respectively. The effect of rice and soybean cultivation on lowering the UAAT was assessed to be 10.5 and $3.0^{\circ}C$ in Suwon, respectively, whereas the differences between the UAAT and canopy temperature at urban paddy and upland in Ansung were 2.6 and $2.2^{\circ}C$. On the other hand, the urban-garden in Suwon city had resulted in lowering the UAAT and the surface temperature of buildings to 2.0 and $14.5^{\circ}C$, respectively. Furthermore, the amounts of $CO_2$ uptake by rice and soybean were estimated to be 20.27 and $15.54kg\;CO_2\;10a^{-1}day^{-1}$, respectively. The amounts of $O_2$ emission by rice and soybean were also assessed to be 14.74 and $11.30kg\;O_2\;10a^{-1}day^{-1}$, respectively. As other cleaning effect of air pollution, the ozone concentrations could be also estimated to reduce 21.0, 8.8, and 4.0 ppb through rice-, soybean cultivation, and urban gardening during most highest temperature period in summer, respectively.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.14 no.1
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• pp.12-25
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• 2003

Objectives：As increasing number of new antidepressants have been being introduced in clinical practice, pharmacological understanding has been broadened. These changes mandate new information and theories to be incorporated into the treatment process of children with depressive disorders. In light of newly coming knowledge, this review intended to recapitulate the characteristics of new antidepressants and to consider the pivotal issues to develope guidelines for the treatment of depression in childhood and adolescence. Methods：Searching the Pub-Med online database for the articles with the key words of 'new', 'antidepressants' and 'children' ninety-seven headings of review articles were obtained. The author selected the articles of pertinent subjects in terms of either treatment guideline or psychopharmacology of new antidepressants. When required, articles about the clinical effectiveness of individual antidepressants were separatedly searched. In addition, the safety information of new antidepressants was acquired by browsing the official sites of the United States Food and Drugs Administration and Department of Health and Human Services. Results：1) For the clinical course, treatment phase, and treatment outcome, the reviews or treatment guidelines adopted the information from adult treatment guidelines. 2) Systematic and critical reviews unambiguously concluded that selective serotonin reuptake inhibitors(SSRIs) excelled tricyclic antidepressants( TCAs) for both efficacy and side effect profiles, and were recommend for the first-line choice for the treatment of children with depressive disorders. 3) New antidepressants generally lacked treatment experiences and randomized controlled clinical trials. 4) SSRIs and other new antidepressants, when used together, might result in pharmacokinetic and/or pharmacodynamic drug-to-drug interaction. 5) The difference of the clinical effectiveness of antidepressants between children and adults should be addressed from developmental aspects, which required further evidence. Conclusion：Treatment guidelines for the pharmacological treatment of childhood and adolescence depression could be constructed on the basis of clinical trial findings and practical experiences. Treatment guidelines are to best serve as the frame of reference for a clinician to make reasonable decisions for a particular therapeutic situation. In order to fulfill this role, guidelines should be updated as soon as new research data become available.

• Journal of the Korean Institute of Gas
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• v.5 no.4 s.16
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• pp.62-69
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• 2001

Gas safety devices are very effective to prevent catastrophic gas accident in domestic. The safety devices are included in domestic gas equipment such as extinguishing safety device and adapted at pipeline such as fuse cock, shut off device with gas alarm and so forth. In spite of using those safety devices, a few hundreds of gas accident was happened annually in residential house. In this study, we analysed systematically the domestic accidents which was happened in five years using fault tree analysis(FTA) method and analysed the effectiveness of individual safety device. And also, it was suggested that the rate of accident was decreased quantitatively by increasing safety device which is adapted in domestic. By analysis of 769 gas accidents in domestic, the order of effectiveness of safety device to prevent domestic gas accident was the multi-functional gas-safe-meter(micom-meter), fuse cock, gas leak alarm and CO alarm. If the above four kind of safety device are adapted to every house, about $59\%$ of accident will be reduced and the most of catastrophic gas accident will be Prevented in domestic.