• New & Renewable Energy
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• v.4 no.1
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• pp.19-24
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• 2008

Energy environment has been changing rapidly such as high oil prices and the effectuation of UNFCCC. Oil prices have continued to rise and Dubai crude prices recorded about 90 dollars per barrel in 2007. In addition, the effectuation of UNFCCC will affect Korean economy and national energy security. Korea is the 9th $CO_2$ emissions country and takes the 1st place related to the increase rate of $CO_2$ emissions globally. Energy technology development is a key breakthrough and one of the optimal alternatives to cope with national energy security. In this study, we prioritize energy technologies in the sectors of high oil prices and UNFCCC related to ETRM for well focus R&D and efficiency of finite resources allocations. We applied to the extended method of AHP, fuzzy AHP reflecting the fuzziness of human thoughts and perception, for prioritizing the relative importance among energy technologies in ETRM for the first time as we make an energy policy in Korea.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.742-746
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• 2007

Energy environment has been changing rapidly such as high oil prices and the effectuation of UNFCCC. Oil prices have continued to rise and Dubai crude prices recorded 60 or 70 dollars per barrel in 2006. In addition, the effectuation of UNFCCC will affect Korean economy and national energy security. Korea is the 9th $CO_2$ emissions country and takes the 1st place related to the increase rate of $CO_2$ emissions globally. Energy technology development is a key breakthrough and one of the optimal alternatives to cope with national energy security. In this study, we prioritize energy technologies in the sectors of high oil prices and UNFCCC related to ETRM for well focus R&D and efficiency of finite resources allocations. We applied to the extended method of AHP, fuzzy AHP reflecting the fuzziness of human thoughts and perception, for prioritizing the relative importance among energy technologies in ETRM for the first time as we make an energy policy in Korea.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.7
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• pp.1387-1393
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• 2007

Even if the linearly separable patterns can be classified by the conventional single layer perceptron, the non-linear problems such as XOR can not be classified by it. A fuzzy single layer perceptron can solve the conventional XOR problems by applying fuzzy membership functions. However, in the fuzzy single layer perception, there are a couple disadvantages which are a decision boundary is sometimes vibrating and a convergence may be extremely lowered according to the scopes of the initial values and learning rates. In this paper, for these reasons, we proposed an enhanced fuzzy single layer perceptron algorithm that can prevent from vibration the decision boundary by introducing a bias term and can also reduce the learn time by applying the modified delta rule which include the learning rates and the momentum concept and applying the new linear activation function. Consequently, the simulation results of the XOR and pattern classification problems presented that the proposed method provided the shorter learning time and better convergence than the conventional fuzzy single layer perceptron.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.39 no.2
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• pp.138-149
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• 2016

Quality function deployment (QFD) is a widely adopted customer-oriented product development methodology by translating customer requirements (CRs) into technical attributes (TAs), and subsequently into parts characteristics, process plans, and manufacturing operations. A main activity in QFD planning process is the determination of the target levels of TAs of a product so as to achieve a high level of customer satisfaction using the data or information included in the houses of quality (HoQ). Gathering the information or data for a HoQ may involve various inputs in the form of linguistic data which are inherently vague, or human perception, judgement and evaluation for the information and data. This research focuses on how to deal with this kind of impreciseness in QFD optimization. In this paper, it is assumed as more realistic situation that the values of TAs are taken as discrete, which means each TA has a few alternatives, as well as the customer satisfaction level acquired by each alternative of TAs and related cost are determined based on subjective or imprecise information and/or data. To handle these imprecise information and/or data, an approach using some basic definitions of fuzzy sets and the signed distance method for ranking fuzzy numbers is proposed. An example of a washing machine under two-segment market is provided for illustrating the proposed approach, and in this example, the difference between the optimal solution from the fuzzy model and that from the crisp model is compared as well as the advantage of using the fuzzy model is drawn.

• Journal of Internet Computing and Services
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• v.1 no.2
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• pp.89-96
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• 2000

Relevance feedback is a technique to learn the user's subjective perception of similarity between images, and has recently gained attention in Content Based Image Retrieval. Most relevance feedback methods assume that the individual features that are used in similarity judgments do not interact with each other. However, this assumption severely limits the types of similarity judgments that can be modeled In this paper, we explore a more sophisticated model for similarity judgments based on fuzzy measures and the Choquet Integral, and propose a suitable algorithm for relevance feedback, Experimental results show that the proposed method is preferable to traditional weighted- average techniques.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2004.04a
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• pp.139-143
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• 2004

Lee et al have proposed a framework for the linguistic map-based navigational planning of a mobile robot on dynamic environment and provided simulation results applied it to the static environment[1], In this paper, we extends the navigational planning of a mobile robot into dynamic environment. There are two kinds of dynamic obstacles： (1) Time-obstacles that change condition of obstacles with time. (2) Space-obstacles that move their position with time. We propose an algorithm which a mobile robot identifies and avoids the two kinds of dynamic obstacles. The proposed algorithm consists of two stages： (1) The fuzzy logic-based perception stage which identifies the dynamic obstacles around a mobile robot by using sensory data and fuzzy rules, (2) The planning stage which plans the path to goal by avoiding the dynamic obstacles[2-6]. We provide computer simulation results for a mobile robot in order to show the validity of the proposed algorithm.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.8 no.2
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• pp.100-104
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• 2008

In this paper, intelligent filtering methodology for masterarm translation signal is proposed. Fidelity and stability are contradicting factors in teleoperation. Human hand trembling filtering is one of the problems in telemanipulation field. During every operation the hand has a certain vibration that can affect the quality of teleoperation, especially in carrying FPD (Flat Panel for Display), nanomanipuation and other precise tasks. It is very important to study the kinesthetic perception of the human and to optimize the teleoperation system accordingly. To cancel out the influence of human's hand vibration the signal from the masterarm should be filtered. One of the feasible solutions is to use an intelligent filter based on fuzzy logic, which is a very flexible instrument. Applying intelligent filtering methodology, we can use some heuristic methods to solve the filtering problem.

• Fibers and Polymers
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• v.7 no.2
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• pp.203-212
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• 2006

The purpose of this study was to examine the effects of the structural properties of plain knit fabrics on the subjective perception of textures, sensibilities, and preference among consumers. This study, then, aimed to provide useful information with respect to planning and designing knitted fabrics by predicting the subjective characteristics analyzed according to their structural properties. For this purpose, we employed statistical analysis tools, such as factor and regression analysis and an adaptive-network-based fuzzy inference system(ANFIS), thereby combining the merits of fuzzy and neural networks and presupposing a non-linear relationship. Through factor analysis, we also categorized the subjective textures into 'roughness', 'softness', 'bulkiness' and 'stretch-ability' with R2=70.32%: and categorized the sensibilities into 'Stable/Neat', 'Natural/Comfortable' and 'Feminine/Elegant' with R2=68.12%. We analyzed subjective textures, sensibilities, and preference with ANFIS, assuming non-linear relationships; consequently, we were able to generate three or four fuzzy rules using wool/rayon fiber content and loop length as input data. The textures of roughness and softness exhibited a linear relationship, but other subjective characteristics demonstrated a non-linear input-output relationship. Compared with linear regression analysis, the ANFIS exhibited had higher predictive power with respect to predicting subjective characteristics.

• Industrial Engineering and Management Systems
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• v.15 no.1
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• pp.77-91
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• 2016

Every service firm must find ways to attract new customers, retain existing customers, and remain competitive and profitable. As competition increases, delivering better service becomes more important. Service quality is considered as a vital aspect for the success of the firms. Restaurant cannot be separated from the service quality they have to deliver. The development of restaurant is supported with the reputation of the country where the food comes from. Recently, one of the most trending topic is Korean wave which affects the Korean cuisine. A fuzzy AHP was employed to evaluate the service quality. It is more preferable than traditional AHP which is criticized for its inability to handle the uncertainty of the decision maker's perception. Six attributes are used to evaluate five Korean restaurants in Semarang, Indonesia. The result shows that innovation is the most important attribute. It seems that decision makers viewed the food variation and new method service as main factors that the restaurants have to manage. This finding can provide the managers with valuable insights into the attribute that reflects customers' perceptions; also to position their service based on their competitors. Validating the scale in other culture-based restaurants is an interesting area to be pursued.

• Journal of Korean Society of Transportation
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• v.12 no.4
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• pp.5-19
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• 1994

The new concept of level of service for the airport system indicates that there must be strong stimulation to proceed with the current stereotyped service standards which are being criticised due to their being based on, either physical capacity/volume or temporal/spatial standards that directly incorporates the perception of passengers. Quantitative factors have been dealt with the main service measurements when evaluating level of service. However, the passenger's perception for the provision service at the airport system is definitely important consideration to assess level of service. To enhance the reliability of service level evaluation from the passenger's point of view, this study has adopted three main evaluation factors ; temporal/spatial factors as quantitative measurements and comfort and reasonable service factors as qualitative measurements. The multi-decision model was constructed using Fuzzy Set Theory and applied to a case study at Seoul Kimpo International Airport. Results are presented in terms of passenger satisfaction with a variety of different values.