• KIPS Transactions on Computer and Communication Systems
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• v.1 no.1
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• pp.35-46
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• 2012

The development of wireless communication systems has resulted in the availability of several access technologies at any geographic area, such as 3G networks, wireless local area networks (WLANs) and wireless broadband networks. The development of these technologies is provided for users who have experienced mobile network environments which are slow or fast-movement environment and change distance between the AP(Access Point). This paper describes network performance issues in various environmental changes. Also, Fuzzy logic is applied to evaluate the performance in vehicle networks around users' environmental factors to focusing on the minimizing of transfer time and costs. First, WLAN and 3G networks fixed distance between AP, Second, WLAN and 3G networks random distance between APs, finally above two environmental with vehicle Ad hoc networks is analyzed. These V2I and V2V environmental condition are assumed. Results which based on Fuzzy logic suggest an optimal performance in vehicle network environments according to vehicle speed and distance between APs. Proposed algorithm shows 21% and 13% improvement of networks performance in V2I and V2V environment.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.1267-1271
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• 2002

Interlocking signalling chart must have no error and ensures a high availability for train operation. Interlocking signalling chart creation needs expert who has much experience to avoid errors, which can provoke some accidents. The CAD system for interlocking signalling chart can replace the expert because it can create the signalling chart without any errors if the creation logic being correct. We have developed the CAD system, present the basic algorithm in this paper.

• Membrane and Water Treatment
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• v.1 no.1
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• pp.75-81
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• 2010

The aim of this work is to analyse and discuss the use of the Economic Evaluation and of some new "metrics" for an appropriate valuation of membrane operations in the logic of Process Intensification. In particular, the proposed approach has the goal to show how the utilized indicators can drive to the choice of the most convenient process. Although in this work the planned procedure is applied, as a case study, to the membrane-based systems for boron and arsenic removal from waters, the suggested approach can be generally applied to any other process of interest.

• Journal of Institute of Control, Robotics and Systems
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• v.11 no.6
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• pp.524-529
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• 2005

In this paper, a novel neural network compensation technique for PD like fuzzy controlled robot manipulators is presented. A standard PD-like fuzzy controller is designed and used as a main controller for controlling robot manipulators. A neural network controller is added to the reference trajectories to modify input error space so that the system is robust to any change in system parameter variations. It forms a neural-fuzzy control structure and used to compensate for nonlinear effects. The ultimate goal is same as that of the neuro-fuzzy control structure, but this proposed technique modifies the input error not the fuzzy rules. The proposed scheme is tested to control the position of the 3 degrees-of-freedom rotary robot manipulator. Performances are compared with that of other neural network control structure known as the feedback error learning structure that compensates at the control input level.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.1
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• pp.1218-1225
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• 2001

This paper presents a design procedure for the supervisory controller(SC) of the high-speed train car. The proposed SC manages control logic and scenario of the overall train system, and monitors input/output signals among the sub-controllers in the system, The roles and functions of each sub-control system are defined, and the interfaces among the control systems are developed. Train control system is modeled with automata, and the model is implemented into a program using a computer-aided software engineering(CASE) tool, Object GEODE, The designed SC is verified and evaluated by using simulation. The SC is shown to successfully perform the designed functions without any errors.

• Journal of Korean Institute of Industrial Engineers
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• v.20 no.3
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• pp.125-137
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• 1994

Manufacturing environs constantly change, and any efficient software system to be used in manufacturing must be able to adapt to the varying situations. In a CAPP (Computer-Aided Process Planning) system, a learning capability is necessary for the CAPP system to do change along with the manufacturing system. Unfortunately only a few CAPP systems currently possess learning capabilities. This research aims at the development of a learning system which can increase the knowledge in a CAPP system. A part in the system is represented by frames and described interactively. The process information and process planning logic is represented using a decision tree. The knowledge expansion is carried out through an interactive expansion of the decision tree according to human advice. Algorithms for decision tree modification are developed. A path can be recommended for an unknown part of limited scope. The processes are selected according to the criterion such as minimum time or minimum cost. The decision tree, and the process planning and learning procedures are formally defined.

• Proceedings of the KIEE Conference
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• 1991.11a
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• pp.345-348
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• 1991

This paper describes a new auto tuning method for the intelligent PID control system. This new method is hosed on the settling time of the process and has been introduced into auto-tuning PID controller using fuzzy logic. The performance of the controller is measured by computer simulation. Simulation shows good results that controller searches well the optimal values of PID parameters in any conditions and the response characteristic of the control system is improved.

• Proceedings of the KIPE Conference
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• 1996.06a
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• pp.43-46
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• 1996

The carborne Automatic Train Control(ATC) system keeps automatically optimum train speed code signals from wayside(track) circuit equipment. If there is no response for braking against the over speed detected, the driver will be noticed instantly by visual and audible warning signals. And then the ATC processes into braking mode for safe train operations to prevent any hazards by over speed limit. In this paper we are introduced the novel ATC system which has triple constructed structure made by 32 bit floating point DSP(ADSP21020-20) and process dealed with frequency domain and time domain for detecting signals. Owing to these reason it is no needed several band pass filters used in conventional ATC systems to detect the speed limit frequency. Also system's reliability and tolerance are incremented by adopt to 2 out of 3 logic to the outputs decision.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.11 no.4
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• pp.286-292
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• 2011

Biometrics systems are used in a wide range of areas, including the area of crime prevention, due to their unique characteristics. However, serious problems can occur if biometric information is disclosed to an unauthorized user. To address these issues, this paper proposes a real valued fuzzy vault method, which adopts a real number error correction code to implement a fuzzy vault scheme for protecting fingerprint temples. The proposed method provides the benefit of allowing the private key value to be changed at any time, unlike biometric template such as a fingerprint, which is not easily renewable even if its security has been breached. The validity of the proposed method is verified for fingerprint verification.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.8 no.1
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• pp.18-23
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• 2008

A FCM with locational price and regional information between locations are proposed in this paper. Any point in a networked system has its own values indicating the physical characteristics of that networked system and regional information at the same time. The similarity measure used for FCM in this paper is defined through the system-wide characteristic values at each point. To avoid the grouping of geometrically distant locations with similar measures, the locational information are properly considered and incorporated in the proposed similarity measure. We have verified that the proposed measure has produced proper classification of a networked system, followed by an example of a networked electricity system.