• KIPS Transactions on Software and Data Engineering
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• v.2 no.11
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• pp.757-764
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• 2013

The estimation of maintenance cost of information system so far has been conducted centered on the ordering body, so the problem of provider's having to cover the cost due to small cost compared to the amount of work is not solved. This study is a base study for estimating the maintenance cost of information system centered on provider, and it deduces cost items of maintenance and suggests adjustment factors for adjusting the gap between the ordering body and provider regarding the maintenance cost. In order to deduce the cost items of maintenance, this study adds the activities of the provider for maintenance to the base study of cost factors regarding the existing maintenance activity, divides, and classifies them into the fixed cost and variable cost. In order to adjust the gap between the ordering body and provider regarding the maintenance cost, this study found the adjustment factors such as the code, utility, and components created by the automatic tool that was not included when estimating the maintenance cost centered on the ordering body. After examining and analyzing K Company's data of maintenance performance for three years, it confirmed that the gap regarding the adjustment factors was about 13% in case of K Company.

• Journal of International Area Studies (JIAS)
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• v.22 no.1
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• pp.161-202
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• 2018

The purpose of this study is to analyze the ex-post evaluation reports of KOICA's grant aid project in terms of criteria, methods, and contents. To this end, we will examine the evaluation history and process with particular reference to EDCF and KOICA. Our key research questions are: 1) How are the evaluation standards of the OECD DAC reflected in the KOICA ex-post evaluation reports? 2) Whether did Korea's practices of development evaluation change after its entry into the OECD DAC. The paper attempted an content analysis on the key words used in findings and recommendation section of the reports since 1998 that ara available on the website of KOICA. The main results can be summarized as follows. First, the frequency of OECD DAC criteria(relevance, efficiency, effectiveness, impact, sustainability) and the use of quantitative methods have been increasing after joining the OECD DAC. Second, in the ex-post evaluation reports issued after 2010, the reference indices including the Project Design Matrix (PDM), baseline data, and performance have increased exponentially.

• Journal of the Korean Society of Radiology
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• v.13 no.3
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• pp.473-479
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• 2019

PET-CT improves performance and reduces the time by combining PET and CT of spatial resolution, and uses CT scan for attenuation correction. This study analyzed PET image evaluation. The condition of the tube voltage and current of CT will be changed using. Uniformity phantom and resolution phantom were injected with 37 MBq $^{18}F$ (fluorine ; 511 keV, half life - 109.7 min), respectively. PET-CT (Biograph, siemens, US) was used to perform emission scan (30 min) and penetration scan. And then the collected image data were reconstructed in OSEM-3D. The same ROI was set on the image data with a analyzer (Vinci 2.54, Germany) and profile was used to analyze and compare spatial resolution and image quality through FWHM and SI. Analyzing profile with pre-defined ROI in each phantom, PET image was not influenced by the change of tube voltage or exposure dose. However, CT image was influenced by tube voltage, but not by exposure dose. When tube voltage was fixed and exposure dose changed, exposure dose changed too, increasing dose value. When exposure dose was fixed at 150 mA and tube voltage was varied, the result was 10.56, 24.6 and 35.61 mGy in each variables (in resolution phantom). In this study, attenuation image showed no significant difference when exposure dose was changed. However, when exposure dose increased, the amount of dose that patient absorbed increased too, which indicates that CT exposure dose should be decreased to minimum to lower the exposure dose that patient absorbs. Therefore future study needs to discuss the conditions that could minimize exposure dose that gets absorbed by patient during PET-CT scan.

• The Journal of the Korea Contents Association
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• v.8 no.5
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• pp.246-259
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• 2008

This study was to minimize the trial and error in the primary step of the C4I system(ATCIS) of the each army corps on the front line, and test the economy and efficiency was tested by reviewing related papers and the system characteristics of other countries. The relationship was researched by analyzing the collected survey data and survey data related to the user's requirement level such as the army standards, that is, commonality, timeliness, simplification, automaticity, field availability and viability, multi-stage security and interoperability, unification. The result showed that the C4I system was efficiently operated through the system reliability for the specification of the system and operation manual, maneuverability and security, adaptability of the war field and system support and management, and good education and training about system operation, and less system maintenance and supplementary element. As a result, the development plan confirmed that the continuous operator education and the construction of the maintenance, and the upgrade digitalization(C4ISR+D) with the korean characteristics based on IT of network systems, and system development of the measurement model of the operator performance must be continuously supplemented in the near future.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.3
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• pp.89-101
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• 2014

Recently, as domestic air traffic dramatically increases, the need of ATC(air traffic control) systems has grown for safe and efficient ATM(air traffic management). Especially, for smooth ATC, it is far more important that performance of display system which should show all air traffic situation in FIR(Flight Information Region) without additional latency is guaranteed. In this paper, we design a ASTERIX(All purpose STructured Eurocontrol suRveillance Information eXchange) parsing module to promote stable ATC by minimizing system loads, which is connected with reducing overheads arisen when we parse ASTERIX message. Our ASTERIX parsing module based on pattern matching creates patterns by analyzing received ASTERIX data, and handles following received ASTERIX data using pre-defined procedure through patterns. This module minimizes display errors by rapidly extracting only necessary information for display different from existing parsing module containing unnecessary parsing procedure. Therefore, this designed module is to enable controllers to operate stable ATC. The comparison with existing general bit level ASTERIX parsing module shows that ASTERIX parsing module based on pattern matching has shorter processing delay, higher throughput, and lower CPU usage.

• The Journal of the Convergence on Culture Technology
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• v.9 no.4
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• pp.363-374
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• 2023

This study is a descriptive research study to confirm the care efficacy and empathy competency of nursing hospital nurses and analyze the factors to improve person-centered care behavior, provide theoretical and practical information accordingly, and prepare basic data. The study collected data from March 20, 2023 to April 20, 2023, targeting 146 nurses at a nursing hospital for the elderly in C region located in G province, and finally analyzed a total of 144 copies. Using IBM SPSS/25, descriptive statistics t-test, ANOVA, and correlation multiple regression analysis were analyzed. As a result of analyzing the variables that affect the subject's person-centered care by hierarchical multiple regression, the higher the caring efficacy and empathy capacity, the more the person-centered care was affected, and the explanatory power was 31.5%. As a result of this study, empathy competency and care efficacy were found to have an effect on person-centered care. It is thought that various measures should be prepared to improve the care efficacy and empathy competency for the efficient nursing performance of person-centered care of nursing hospital nurses.

• Journal of Korea Water Resources Association
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• v.49 no.8
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• pp.685-692
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• 2016

This study aimed to develop the indicator-based approach to assess water use vulnerability in watersheds and applied to the unit watershed within the Han River watershed. Vulnerability indices were comprised of three sub-components (exposure, sensitivity, adaptive capacity) with respect to water use. The indicators were made up of 16 water use indicators. Then we estimated vulnerability indices using the Technique for Order of Preference by Similarity to Ideal Solution approach (TOPSIS). We collected environmental and socio-economic data from national statistics database, and used them for simulated results by the Soil and Water Assessment Tool (SWAT) model. For estimating the weighted values for each indicator, expert surveys for subjective weight and data-based Shannon's entropy method for objective weight were utilized. With comparing the vulnerability ranks and analyzing rank correlation between two methods, we evaluated the vulnerabilities for the Han River watershed. For water use, vulnerable watersheds showed high water use and the water leakage ratio. The indices from both weighting methods showed similar spatial distribution in general. Such results suggests that the approach to consider different weighting methods would be important for reliably assessing the water use vulnerability in watersheds.

• The Journal of the Convergence on Culture Technology
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• v.10 no.3
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• pp.461-466
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• 2024

Korean local governments operates the participatory budgeting system autonomously. This study is to classify these entities into clusters. Among the diverse machine learning methodologies(Neural Network, Rule Induction(CN2), KNN, Decision Tree, Random Forest, Gradient Boosting, SVM, Naïve Bayes), the Support Vector Machine technique emerged as the most efficacious in the analysis of 2022 Korean municipalities data. The first cluster C1 is characterized by minimal committee activity but a substantial allocation of participatory budgeting; another cluster C3 comprises cities that exhibit a passive stance. The majority of cities falls into the final cluster C2 which is noted for its proactive engagement in. Overall, most Korean local government operates the participatory busgeting system in good shape. Only a small number of cities is less active in this system. We anticipate that analyzing time-series data from the past decade in follow-up studies will further enhance the reliability of classifying local government types regarding participatory budgeting.

• Journal of Intelligence and Information Systems
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• v.24 no.2
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• pp.243-264
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• 2018

Although the worldwide battery market is recently spurring the development of lithium secondary battery, lead acid batteries (rechargeable batteries) which have good-performance and can be reused are consumed in a wide range of industry fields. However, lead-acid batteries have a serious problem in that deterioration of a battery makes progress quickly in the presence of that degradation of only one cell among several cells which is packed in a battery begins. To overcome this problem, previous researches have attempted to identify the mechanism of deterioration of a battery in many ways. However, most of previous researches have used data obtained in a laboratory to analyze the mechanism of deterioration of a battery but not used data obtained in a real world. The usage of real data can increase the feasibility and the applicability of the findings of a research. Therefore, this study aims to develop a model which predicts the battery deterioration using data obtained in real world. To this end, we collected data which presents change of battery state by attaching sensors enabling to monitor the battery condition in real time to dozens of golf carts operated in the real golf field. As a result, total 16,883 samples were obtained. And then, we developed a model which predicts a precursor phenomenon representing deterioration of a battery by analyzing the data collected from the sensors using machine learning techniques. As initial independent variables, we used 1) inbound time of a cart, 2) outbound time of a cart, 3) duration(from outbound time to charge time), 4) charge amount, 5) used amount, 6) charge efficiency, 7) lowest temperature of battery cell 1 to 6, 8) lowest voltage of battery cell 1 to 6, 9) highest voltage of battery cell 1 to 6, 10) voltage of battery cell 1 to 6 at the beginning of operation, 11) voltage of battery cell 1 to 6 at the end of charge, 12) used amount of battery cell 1 to 6 during operation, 13) used amount of battery during operation(Max-Min), 14) duration of battery use, and 15) highest current during operation. Since the values of the independent variables, lowest temperature of battery cell 1 to 6, lowest voltage of battery cell 1 to 6, highest voltage of battery cell 1 to 6, voltage of battery cell 1 to 6 at the beginning of operation, voltage of battery cell 1 to 6 at the end of charge, and used amount of battery cell 1 to 6 during operation are similar to that of each battery cell, we conducted principal component analysis using verimax orthogonal rotation in order to mitigate the multiple collinearity problem. According to the results, we made new variables by averaging the values of independent variables clustered together, and used them as final independent variables instead of origin variables, thereby reducing the dimension. We used decision tree, logistic regression, Bayesian network as algorithms for building prediction models. And also, we built prediction models using the bagging of each of them, the boosting of each of them, and RandomForest. Experimental results show that the prediction model using the bagging of decision tree yields the best accuracy of 89.3923%. This study has some limitations in that the additional variables which affect the deterioration of battery such as weather (temperature, humidity) and driving habits, did not considered, therefore, we would like to consider the them in the future research. However, the battery deterioration prediction model proposed in the present study is expected to enable effective and efficient management of battery used in the real filed by dramatically and to reduce the cost caused by not detecting battery deterioration accordingly.

• Journal of Korea Society of Industrial Information Systems
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• v.14 no.5
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• pp.289-296
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• 2009

All over the world more and more attention is being paid to green management which enables environment-friendly sustainable development. To keep up with these global trends and in response to the government's "low carbon green growth" policy, many efforts are being made in the port and logistics in order to drastically reduce carbon emissions and save operating expenses. To this end, the engine power source of the cranes in the container terminal is being replaced with electricity from fossil fuel. Among those cranes, especially e-RTGC has been proved to be practical and excellent in its performance through many previous studies. However, no empirical study has yet been made on its introduction effects when e-RTGC has been introduced to the container terminal. In the meantime, however, many domestic container terminals have introduced e-RTGC, and so some data have been accumulated for further research. Under these circumstances, this study has tried to make an empirical study through the case study of D container terminal, checking the restriction factors to be considered at the time of eURTGC introduction, and analyzing its introduction effects and problems. We have high expectations that this study will provide key consideration factors and empirical analysis data to the decision makers who plan to introduce an e-RTGC system, and also will be used as a reference to the development direction of e-RTGC.