• Journal of Korea Multimedia Society
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• v.22 no.9
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• pp.1069-1079
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• 2019

In this study, we developed a $PM_{10}$ forecasting model using DNN and Membership Function, and improved the forecasting performance. The model predicts the $PM_{10}$ concentrations of the next 3 days in the Seoul area by using the weather and air quality observation data and forecast data. The best model(RM14)'s accuracy (82%, 76%, 69%) and false alarm rate(FAR:14%,33%,44%) are good. Probability of detection (POD: 79%, 50%, 53%), however, are not good performance. These are due to the lack of training data for high concentration $PM_{10}$ compared to low concentration. In addition, the model dose not reflect seasonal factors closely related to the generation of high concentration $PM_{10}$. To improve this, we propose Julian date membership function as inputs of the $PM_{10}$ forecasting model. The function express a given date in 12 factors to reflect seasonal characteristics closely related to high concentration $PM_{10}$. As a result, the accuracy (79%, 70%, 66%) and FAR (24%, 48%, 46%) are slightly reduced in performance, but the POD (79%, 75%, 71%) are up to 25% improved compared with those of the RM14 model. Hence, this shows that the proposed Julian forecast model is effective for high concentration $PM_{10}$ forecasts.

• Journal of the Korea Management Engineers Society
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• v.23 no.4
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• pp.87-103
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• 2018

This paper introduces the method to develop two main types of the fuzzy OEE (Overall Equipment Effectiveness) models via triangular membership function for measuring uncertainty. The fuzzy OEE includes model type 1 and model type 2. The model type 1 is used when the theoretical machine speed only reflects the time loss whereas model type 2 is used when the actual machine speed reflects both time and speed loss. Model type 2 has shown to perform a lower availability rate and a higher performance rate compared to model type 1. In addition, the fuzzy UPH (Unit Per Hour) which is derived from using the fuzzy OEE is presented to satisfy demand uncertainty. The fuzzy UPH can easily measure the fuzzy tact time and cycle time by reciprocating itself. Finally, this study demonstrates the fuzzy OEE models using IVIFS (Interval-Valued Intuitionistic Fuzzy Set) based on the characterization via membership function, non-membership function and hesitant function. For the purpose of analyzing the fuzzy system OEE, the OEE for each machine of plant structure is considered triangular interval-valued intuitionistic fuzzy number. Regardless of plant structure, the validity degree of fuzzy membership function of system OEE decreases when the number of machine with worst value of the validity degree increases. Corresponding examples are presented in this paper for practitioner to understand the applicability and practicability of the proposed fuzzy OEE methods.

• Proceedings of the Korea Technology Innovation Society Conference
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• 2017.08a
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• pp.101-122
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• 2017

As business paradigm shifts toward the convergence of technology and industry, so-called the fourth industrial revolution, research and development on enterprises is becoming the core capability of growth momentum for the future. Accordingly, Management of Technology (MOT) is being paid attention to construct systematical planning and operations on technological strategy, thereby increasing the importance of cooperative relationship in MOT-relevant domains. Due to this reason, academia manages the family membership system that enables mutual collaborations between academia and industry to achieve their win-win strategy and makes customized cooperative systems to share their human and property resources systematically. Particularly, it is vital to operate the family membership system effectively and efficiently in the MOT domain because family enterprises need to endeavor the establishment of value-toward technology strategy within the framework of those cooperative systems. For such the purpose, this paper presents the analysis of the state-of-the art of the family membership system managed by Graduate School of Management of Technology at Pukyong National University. This paper also proposes vitalization strategies of this membership system so that famliy enterprises located in the east-southern area in Republic of Korea can gain MOT-oriented innovative capability.

• The Journal of Korean Association of Computer Education
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• v.7 no.2
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• pp.77-84
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• 2004

In this thesis, We propose the self-directed learning and test-performing abilities assessment method to evaluate the learning and the test-performing abilities in which learners can not only control their own learning abilities for themselves, but also judge objectively learning and test-performing abilities. This method shows the membership degree of learning and test-performing abilities by using both the triangle-type membership function and the fuzzy logic. In addition, it gives the fuzzy grades to each item. The final membership degrees are calculated and the fuzzy grades are decided by the operation and composition of fuzzy relations on the membership degrees of learning and test-performing abilities. In this method, which is applicable to a writing subject for information searchers, learners are asked to analyse the membership degrees of the learning and test-performing abilities and the final fuzzy grades and to adjust a learning process for themselves.

• Journal of Labour Economics
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• v.29 no.2
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• pp.117-143
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• 2006

This paper illuminates the patterns of growth and declines in sizes of union membership in metal, chemical, financial, and auto transport sectors in three distinct periods during the last four decades from 1963 to 2003. This paper also calculates union densities in auto assembly, auto supply, and shipbuilding industries of the metal sector, cement, petroleum refining, and pharmaceutical industries of the chemical sector, private banking industry of the financial sector, and city bus industry of the auto transport sector. Such diversities in both sizes of union membership and union densities among sectors and industries turned out to be associated with attitudes and choices of employers and unions in interaction with sector- and industry-specific economic (growth stage and path), institutional (degrees of government intervention), and social (demographic features of employees and prevailing sizes of firms) environment. Such finding shows that theoretical reasonings on sizes of union membership and union densities across sectors and industries in advanced nations are also relevantly useful to analyze the Korean case.

• Journal of the Korean Home Economics Association
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• v.46 no.10
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• pp.107-117
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• 2008

The purpose of this study was to analyze customer attraction effects of restaurant promotion for kids. The questionnaires were distributed to 300 parents who have children under 12 years old and a total of 269 questionnaires were collected and used in analysis(usage rate 90.0%). The data was analyzed using SPSS 12.0 for descriptive analysis and paired t-test. The major results were as follows; First, customers mainly got information on coupon from mail. In case of premium and membership, the information was obtained when customers were visiting restaurants. Second, among the types of promotion for kids, coupon was mostly preferred by customers. 'Discount coupon' for the coupon, 'free gift' for the premium and 'pay-back' program for the membership were more preferable than other types of kids promotion. Third, A 'discount coupon' was more effective than 'free coupon'(p<.0l) in term of customer inducement. In case of premium, 'free gift' was more effective than 'lottery'(p<.05) and in case of membership, the customer attraction effect was not significantly different according to the types of membership. In case of coupon and membership, it was more effective in family restaurant than fastfood restaurant(p<.05), but the effect of premium was not significantly different in family vs fastfood restaurant. The results of the study revealed that 'coupon' was the most preferred type of promotion for kids and specifically customers preferred 'discount coupon', 'free gift' and 'pay-back program'.

• Journal of Korean Port Research
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• v.15 no.1
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• pp.37-46
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• 2001

Fuzzy logic control(FLC) is composed of three parts : fuzzy rule-bases, membership functions, and scaling factors. Well-defined fuzzy rule-base should contain proper physical intuition on the plant, so are needed lots of experiences of the skillful expert. When membership functions are considered, some parameters on the memberships function such as function shape, support, allocation density should be selected well. The rule of scaling factors is 'scaling'(amplifying or reducing) for both input and output signals of the FLC to fit in the membership function support and to operate the plant intentionally. To get a better performance of the FLC, it is necessary to adjust the parameters of the FLC. In general, the adaptation of the scaling factors is the most effective adjustment scheme, compared with that of the fuzzy rule-base or membership function parameters. This study proposes the adaptation scheme of the scaling factors. When the adaptation is performed on-line, the stability of the adaptive FLC should be guaranteed. The stable FLC system can be designed with stability analysis in the sense of Lyapunov stability. To adapt the scaling factors for the error signals, the concept of the conventional MRAC would be introduced into slightly modified form. A tracking accuracy of the control system would be enhanced by the modified shape and support of the membership function. The simulation is achieved on the pilot plant with the hydraulic steering control of a UCT(Unmanned Container Transporter) of which modeling dynamics have lots of severe uncertainties and modeling errors.

• Culinary science and hospitality research
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• v.17 no.1
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• pp.110-123
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• 2011

The purpose of this paper is twofold: (1) to investigate how the online communities of restaurants affect the members and create the value by exploring some desirable member behaviors related to the membership, and (2) to examine the possible moderating effect of topic involvement on a member behavior paradigm. The sense of membership was proposed as a prerequisite determinant of two basic member behavior (i.e., purchase-related behavior and group-related behavior). Results of this study confirmed that the level of a member's sense of membership had a positive effect on his/her member behavior. The topic involvement levels of a member was further revealed to strengthen the magnitudes of the proposed relationships. Highly involved members were more likely to engage in both purchase-related behavior and group-related behavior when they were attached to their communities.

• Journal of the Korean Society of Marine Environment & Safety
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• v.12 no.2 s.25
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• pp.145-150
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• 2006

This paper proposes an analysis to image of Inchon port using fuzzy theory. After analysis, positive opinion is mean membership function 0.73 and positive membership function 0.27, negative opinion is mean membership function 0.69, negative membership function 0.31 about Inchon port development. therefore, for port development need to accomodation of each opinion positive opinion is maximum decrease from 20 age to 30 age. and negative opinion is maximum increase from 10 age to 20 age. According to the results, port development need to high positive image as leisure and development of waterfront and low negative image as integrated port management and strategy of considered environment port.

• Journal of the Korea Society of Computer and Information
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• v.11 no.3
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• pp.11-20
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• 2006

This paper describes the technique which utilizes a fuzzy neural network to sketch feature extraction in digital images. We configure an artificial neural network and make it learn fuzzy membership functions to decide a local threshold applying to sketch feature extraction. To do this. we put the learning data which is membership functions generated based on optimal feature map of a few standard images into the artificial neural network. The proposed technique extracts sketch features in an images very effectively and rapidly because the input fuzzy variable have some desirable characteristics for feature extraction such as dependency of local intensity and excellent performance and the proposed fuzzy neural network is learned from their membership functions, We show that the fuzzy neural network has a good performance in extracting sketch features without human intervention.