• Journal of Korean Institute of Industrial Engineers
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• v.36 no.1
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• pp.69-77
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• 2010

The failure rate model of External Environment Maintenance(EEM) for a system under severe environment is investigated. EEM, which is recently introduced concept, is a maintenance activity controlling external environment factors that potentially cause system failure such as cleaning equipment, controlling temperature (humidity) and removing dust inside of electronic appliances. EEM can not have any influence on the inherent failure rate of a system but reduce the severity of the external environment causing failure since it deals with only external environment factors. Therefore, we propose two failure rate models to express the improvement effect of EEM: The intensity reduction model and age reduction model. The intensity and age reduction models of EEM are developed assuming the quality of improvement effect is proportioned to an extra intensity or age respectively. The validation of proposed failure rate models is performed in order of data generation, parameter estimation and test for goodness-of-fit.

• Korean Journal of Rural Living Science
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• v.7 no.2
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• pp.139-152
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• 1996

The objectives of this study are : (1) to measure the level of economic stress perception in Korean farm households. (2) to identify the effects of related variables such as socio-demographic variables and economic stability. The data from 505 farm households' wives was analyzed using statistical methods such as frequency, correlation, oneway ANOVA, lease significant difference test, and stepwise multiple regression. The major findings are as follows : The mean value of economic stress perception on the 505 wives was 33.5 points out of a possible 100. Among 3 subsectors, income stress perception had highest score. Socio- demographic variables such as family size, type of farm household, financial manager, debt, credit . grant assistant, wife's age, and educational level of the wife had a significant difference on the economic stress perception of wives in the ANOVA analysis. So did the objective and subjective evaluation of economic stability. As a result of multiple regression analysis, economic stability, debt presence, and wife age were verified explaining 23% of the variance of economic stress perception. Therefore, it can be said that farm wives had relatively high economic stress perception in the case of low economic stability, getting into debt and low age.

• Journal of Korea Society of Digital Industry and Information Management
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• v.8 no.2
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• pp.31-40
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• 2012

Face recognition refers to the process of identifying individuals based on their facial features. It has recently become one of the most popular research areas in the fields of computer vision, machine learning, and pattern recognition because it spans numerous consumer applications, such as access control, surveillance, security, credit-card verification, and criminal identification. However, illumination variation on face generally cause performance degradation of face recognition systems under practical environments. Thus, this paper proposes an novel face recognition system using a fusion approach based on local binary pattern and two-dimensional principal component analysis. To minimize illumination effects, the face image undergoes the local binary pattern operation, and the resultant image are divided into two sub-images. Then, two-dimensional principal component analysis algorithm is separately applied to each sub-images. The individual scores obtained from two sub-images are integrated using a weighted-summation rule, and the fused-score is utilized to classify the unknown user. The performance evaluation of the proposed system was performed using the Yale B database and CMU-PIE database, and the proposed method shows the better recognition results in comparison with existing face recognition techniques.

• Journal of Information Processing Systems
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• v.16 no.5
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• pp.1113-1128
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• 2020

Ad hoc networks play an important role in mobile communications, and the performance of nodes has a significant impact on the choice of communication links. To ensure efficient and secure data forwarding and delivery, an intelligent routing protocol (IAODV) based on learning method is constructed. Five attributes of node energy, rate, credit value, computing power and transmission distance are taken as the basis of segmentation. By learning the selected samples and calculating the information gain of each attribute, the decision tree of routing node is constructed, and the rules of routing node selection are determined. IAODV algorithm realizes the adaptive evaluation and classification of network nodes, so as to determine the optimal transmission path from the source node to the destination node. The simulation results verify the feasibility, effectiveness and security of IAODV.

• Journal of Korea Society of Digital Industry and Information Management
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• v.16 no.3
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• pp.13-23
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• 2020

Currently, online means of replacing resident registration numbers(RRN) include I-Pin, mobile phone, credit card, MyPin, and general-purpose certificate. In order to issue alternative means based on the RRN, it must be designated through the designation review by the Korea Communications Commission(KCC) through a designation review by personal proofing agency and be subject to annual management. However, the criteria for designation and follow-up of the designation of the personal proofing agency carried out by KCC have been used in 2010 without revision, and there are problems that do not conform to the evaluation standards of various alternative means. Therefore, in this paper, we propose a method for improving the designation criteria and management system of the personal proofing service agency. The proposed method analyzes the characteristics of the alternative identification-based personal proofing service and proposes a follow-up management standard that can appropriately evaluate the analyzed characteristics and improves the designation criteria according to the emergence of new alternatives. Through the proposed method, it can be seen that it is possible to strengthen the safety of the personal proofing service based on the alternative means of RRN provided online and face-to-face and to protect the user's personal information.

• Journal of the Korean Society for Library and Information Science
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• v.17
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• pp.261-273
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• 1989

The study attempted to determine if the effectiveness of bibliographic 'instruction would be different among student groups, divided by grade levels, major areas of study, and the level of library skills posessed before the instruction. The focal point of the investigation was the degree of improvement demonstrated by the changes in mean score of each group after taking bibliographic instruction. Sangmyong Women's University students who have taken the bibliographic instruction course for credit were the subjects of the study. Students' library skills were measured prior to the bibliographic instruction and post-test was followed. And the measured was based on the 'Library skills Test' developed by the Illinois Association of College and Research Libraries. Three hypotheses in the study were tested statistically by ANOVA. The followings are the results of the analysis: (1) There were no significant differences in bibliographic instruction effectiveness among student groups divided by grade levels; (2) There were significant differences (p<.01) in bibliographic instruction effectiveness among student groups divided by major areas of study. Bibliographic instruction was more effective for humanities or social sciences majors than for performing arts or physical education majors; (3) There were significant differences (p<.001) in bibliographic instruction effectiveness among student groups divided by the initial library skills. Obviously, bibliographic instruction was more effective for the students in bottom quartile than those in top quartile or middle quartiles. Finally, limitations of the study, recommendations based on the results and area for future research are briefly examined.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.7
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• pp.161-167
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• 2021

Nowadays, small- and medium-sized enterprises (SMEs) are placed among the key components of the economy in both developed and developing countries. They are internationally known as the driving force based on their enormous contributions to Gross Domestic Product (GDP) and generating new employment. They are generally presumed as the leader of environmental sustainability, economic prosperity, and innovation, particularly for the economy of developing countries such as Vietnam. However, SMEs have difficulty in raising capital, as well as access to credit. One of the reasons is that there are inadequacies in accounting information quality in SMEs as well as the provision of accounting information and accounting information confidentiality. The main objective of this study was to identify, evaluate, and measure the attributes of accounting information quality of SMEs in Hanoi. The study was based on a field survey using a semi-structured questionnaire on a sample of 150 accountants. The study has identified and measured six (6) attributes of accounting information quality of SMEs that have great effects on accountants. There is, statistically, no significant difference in the level of accounting information quality of SMEs in Hanoi from these different business areas. There is no, statistically, significant difference in the level of accounting information quality of SMEs in Hanoi between the mentioned three groups of the job description. Based on the findings, some recommendations are given for SMEs to improve accounting information quality.

• International Journal of Computer Science & Network Security
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• v.21 no.3
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• pp.127-133
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• 2021

Today, phishing attacks represent one of the biggest security threats targeting users of the digital world. They consist of an attempt to steal sensitive information, such as a user's identity or credit and debit card details, using various methods that include fake emails, fake websites, and fake social media messages. Protecting the user's security and privacy therefore becomes complex, especially when those users are children. Currently, children are participating in Internet activity more frequently than ever before. This activity includes, for example, online gaming, communication, and schoolwork. However, children tend to have a less well-developed knowledge of privacy and security concepts, compared to adults. Consequently, they often become victims of cybercrime. In this paper, the effects of security awareness on users who are children are investigated, looking at their ability to detect phishing attacks in social media. In this approach, two Experiments were conducted to evaluate the effects of security awareness on WhatsApp application users in their daily communication. The results of the Experiments revealed that phishing awareness training has a significant positive effect on the ability of children using WhatsApp to identify phishing messages and thereby avoid attacks.

• The Journal of Economics, Marketing and Management
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• v.9 no.1
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• pp.25-40
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• 2021

Purpose: The forecasting is the likelihood scientifically proved judgment about the prospects, the possible conditions of this or that phenomenon in the future and (or) about the alternative ways and the means of their realization. To adapt the instruments of budgeting for the analysis cash flow of company. Research design, data and methodology: The creates the budget of cash flow were carried out on the basis of data of the report for the 2017 of corporations POSCO and in the first half of the 2018 Daewoo Shipbuilding & Marine Engineering of South Korea. Results: The simultaneous use of budgeting techniques and the simple financial analysis allows to systematize the transactions, to identify the main problem areas in the movement cash flows. Therefore, working capital analysis is to determine the limits of their fluctuations in view of the changes in the business processes. Conclusions: In the pedagogical context solved the features of budgeting in the part evaluation current assets, its financing, its elements: the cash, the debtor. In the process of budgeting of cash flow, in credit budget, in financial budget we can see the main indicators: the current assets, the functioning capital, the optimum number of debtors, the optimum amount of cash and another.

• The Korean Journal of Applied Statistics
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• v.35 no.1
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• pp.77-91
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• 2022

The optimal threshold estimation is considered in order to discriminate the mixture distribution in the fields of Biostatistics and credit evaluation. There exists well-known various accuracy measures that examine the discriminant power. Recently, Matthews correlation coefficient and the F1 statistic were studied to estimate optimal thresholds. In this study, we explore whether these accuracy measures are appropriate for the optimal threshold to discriminate the mixture distribution. It is found that some accuracy measures that depend on the sample size are not appropriate when two sample sizes are much different. Moreover, an alternative method for finding the optimal threshold is proposed using the correlation coefficient that defines the ratio of the confusion matrix, and the usefulness and utility of this method are also discusses.