• Journal of Korean Society of Transportation
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• v.23 no.2
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• pp.25-36
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• 2005

In this study, we suggested a new approach method forecasting distribution demand of urban rail transit usign fuzzy control, with intend to reflect irregularity and various functional relationship between trip length and distribution demand. To establish fuzzy control model and test this model, the actual trip volume(production, attraction and distribution volume) and trip length (space distance between a departure and arrival station) of Daegu subway line 1 were used. Firstly, usign these data we established a fuzzy control model, nd the estimation accuracy of the model was examined and compared with that of generalized gravity model. The results showed that the fuzzy control model was superior to gravity model in accuracy of estimation. Therefore, wwe found that fuzzy control was able to be applied as a effective method to predict the distribution demand of urban rail transit. Finally, to increase the estimation precision of the model, we expect studies that define membership functions and set up fuzzy rules organized with neural networks.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.1
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• pp.240-259
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• 2020

Analyzing network traffic is the basis of dealing with network security issues. Most of the network security systems depend on the feature selection of network traffic data and the detection ability of malicious traffic in network can be improved by the correct method of feature selection. An FAFS method, which is short for Fuzzy Association Feature Selection method, is proposed in this paper for network malicious traffic detection. Association rules, which can reflect the relationship among different characteristic attributes of network traffic data, are mined by association analysis. The membership value of association rules are obtained by the calculation of fuzzy reasoning. The data features with the highest correlation intensity in network data sets are calculated by comparing the membership values in association rules. The dimension of data features are reduced and the detection ability of malicious traffic detection algorithm in network is improved by FAFS method. To verify the effect of malicious traffic feature selection by FAFS method, FAFS method is used to select data features of different dataset in this paper. Then, K-Nearest Neighbor algorithm, C4.5 Decision Tree algorithm and Naïve Bayes algorithm are used to test on the dataset above. Moreover, FAFS method is also compared with classical feature selection methods. The analysis of experimental results show that the precision and recall rate of malicious traffic detection in the network can be significantly improved by FAFS method, which provides a valuable reference for the establishment of network security system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.7
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• pp.350-356
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• 2017

With increasing attention to real-time body detection, active research is being conducted on human body detection based on skin color. Despite this, most existing skin detection methods utilize static skin color models and have detection rates in images, in which colors are distorted. This study proposed a method of detecting the skin region using a fuzzy classification of the gradient map, saturation, and Cb and Cr in the YCbCr space. The proposed method, first, creates a gradient map, followed by a saturation map, CbCR map, fuzzy classification, and skin region binarization in that order. The focus of this method is to rigorously detect human skin regardless of the lighting, race, age, and individual differences, using features other than color. On the other hand,the borders between these features and non-skin regions are unclear. To solve this problem, the membership functions were defined by analyzing the relationship between the gradient, saturation, and color features and generate 108 fuzzy rules. The detection accuracy of the proposed method was 86.35%, which is 2~5% better than the conventional method.

• Journal of Korean Society of Transportation
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• v.24 no.7 s.93
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• pp.81-90
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• 2006

It is important to clarify the relationship between traffic accidents and various influencing factors in order to reduce the number of traffic accidents. This study developed a traffic accident frequency prediction model using by multi-linear regression and qualification theories which are commonly applied in the field of traffic safety to verify the influences of various factors into the traffic accident frequency The data were collected on the Korean National Highway 17 which shows the highest accident frequencies and fatality rates in Chonbuk province. In order to minimize the uncertainty of the data, the fuzzy theory and neural network theory were applied. The neural network theory can provide fair learning performance by modeling the human neural system mathematically. Tn conclusion, this study focused on the practicability of the fuzzy reasoning theory and the neural network theory for traffic safety analysis.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.7 no.3
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• pp.133-141
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• 2012

Service and manufacturing companies' efforts are increasingly focused on utilizing services to satisfy customers' needs and survive in today's competitive market environment. The value of services depends mainly on service reliability that is identified by satisfaction derived from the relationship between customer and service provider. In this paper, we extend concepts from the failure modes and effects analysis of tangible systems to services. We use an event-based process model to facilitate service design and represent the relationships between functions and failures in a service. The objective of this research is to propose a method for evaluating service reliability based on service processes using fuzzy failure mode effects analysis (FMEA) and grey theory. We define the failure mode of service as interaction ways that can be failed in a service delivery process. The fuzzy set theory is used to characterize service reliability based on linguistic terms during FMEA. Grey theory is employed to determine the degree of relation and ranking among risk factors that are represented as potential failure causes. To demonstrate implementation of the proposed method, we use a case study involving a typical automotive service operation.

• Journal of Microbiology and Biotechnology
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• v.28 no.7
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• pp.1052-1060
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• 2018

Numerous studies suggest that the effects of lactic acid bacteria (LAB) on oxidative stress in vivo are correlated with their antioxidative activities in vitro; however, the relationship is still unclear and contradictory. The antioxidative activities of 27 Lactobacillus plantarum strains isolated from fermented foods were determined in terms of 2,2-diphenyl-1-picrylhydrazyl, hydroxyl radical, and superoxide radical scavenging abilities, reducing activity, resistance to hydrogen peroxide, and ferrous chelating ability in vitro. Two fuzzy synthetic evaluation models, one with an analytic hierarchy process and one using entropy weight, were then used to evaluate the overall antioxidative abilities of these L. plantarum strains. Although there was some difference between the two models, the highest scoring strain (CCFM10), the middle scoring strain (CCFM242), and the lowest scoring strain (RS15-3) were obtained with both models. Examination of the antioxidative abilities of these three strains in $\text\tiny{D}$-galactose-induced oxidative stress mice demonstrated that their overall antioxidative abilities in vitro could reveal the abilities to alleviate oxidative stress in vivo. The current study suggests that assessment of overall antioxidative abilities with fuzzy synthetic models can guide the evaluation of probiotic antioxidants. It might be a more quick and effective method to evaluate the overall antioxidative abilities of LAB.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.8
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• pp.1468-1484
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• 1992

In the present paper forward projection is proposed as a new approach to determine the preform shape in rib-web type forging. In the forward projection technique an optimal billet is determined by applying some mathematical relationship between geometrical trials in the initial billet shape and the final products. In forward projection a volume difference between the desired product shape and the final computed shape obtained by the rigid-plastic finite element method is used as a measure of incomplete filling of working material in the die. At first linear inter-/extrapolation is employed to find a proper trial shape for the initial billet and the method is successfully applied to some cases of different aspect ratios of the initial billet. However, when the initial guesses are not sufficiently near the optimal value linear inter-/extrapolation does not render complete die filling. For more general application, a fuzzy system is used in the forward projection technique in order to determine the initial billet shape for rib-web type forging. It has been thus shown that the fuzzy system is more reliable for the preform design in the rib-web type forging process.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.2
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• pp.228-237
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• 2021

In those day, the Busan local government had instituted a rule to support and enhance competition as well as improve respect for the ship management industry. This study aims to extract the cause factors to enhance such competition using intuitionistic decision making trial and evaluation laboratory (DEMATEL) and interpretive structural modeling (ISM) methods. First, eight factors were extracted from the specifications in the Ship Management Industry Development Act. Second, the intuitionistic fuzzy number was converted to a crisp number using the standard fuzzy number. Third, the influence relationship was analyzed using DEMATEL, and the priority ranks for the factors are determined using ISM. From the results of the impact relationship analysis, the three main cause factors were determined as improvement of technical ship management capability, improvement of expertise of manpower for onshore management, and improvement of the quality of the Korean seafarer. The priorities under the ISM method, in descending order, were as follows: improvement of the quality of Korean seafarers, improvement of professionalism among the manpower for shore management, improvement of technical ship management capability, improvement of commercial ship management capability, establishment of a comprehensive information system, improvement of the working conditions and employment environment for seafarers, financial support such as overseas orders, and strengthening the availability of foreign seafarers. Therefore, it is necessary to prioritize policy promotion based on these factors, especially the top three, as these have the highest impact.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.4 no.2
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• pp.129-134
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• 2004

XML is the new universal format for structured documents and data on the World Wide Web. As the Web becomes a major means of disseminating and sharing information and as the amount of XML data increases substantially, there are increased needs to manage and design such XML document in a novel yet efficient way. Moreover a demand of XML Schema(W3C XML Schema Spec.) that verifies XML document becomes increasing recently. However, XML Schema has a weak point for design because of its complication despite of various data and abundant expressiveness. Thus, it is difficult to design a complex document reflecting the usability, global and local facility and ability of expansion. This paper shows a simple way of modeling for XML document using a fundamental means for database design, the Entity-Relationship model. The design from the Entity-Relationship model to XML Schema can not be directly on account of discordance between the two models. So we present some algorithms to generate XML Schema from the Entity-Relationship model. The algorithms produce XML Schema codes using a hierarchical view representation. An important objective of this modeling is to preserve XML Schema's object-oriented concepts such as reusability, global and local ability. In addition to, implementation procedure and evaluation of the proposed design method are described.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.2 no.1
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• pp.83-88
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• 2002

We study some properties of smooth uniform spaces. We investigate the relationship between smooth topological spaces and smooth uniform spaces. In particular, we define a subspace of a smooth uniform space and a product of smooth uniform spaces.