• International Journal of Fuzzy Logic and Intelligent Systems
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• v.6 no.2
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• pp.155-160
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• 2006

In the paper a robust indirect adaptive fuzzy controller is proposed for balancing and position control of the inverted pendulum system. Because balancing control rules of the pendulum and position control rules of the cart can be opposite, it is difficult to design an adaptive fuzzy controller that satisfy both objectives. To stabilize the pendulum at a specified position, the proposed fuzzy controller consists of a robust indirect adaptive fuzzy controller for balancing and a supervisory fuzzy controller which emulates heuristic control strategy and arbitrate two control objectives. It is proved that the signals in the overall system are bounded. Simulation results are given to verify the proposed adaptive fuzzy control method.

• The Transactions of the Korea Information Processing Society
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• v.4 no.10
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• pp.2470-2476
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• 1997

We propose a new real-time search algorithm and provide experimental evaluation and comparison of the new algorithm with mini-min lookahead algorithm. Many other real-time heuristic-search approached often divide the problem space to several sub-problems. In this paper, the proposed algorithm guarantees not only the sub-problem deadline but also total deadline. Several heuristic real-time search algorithms such as $RTA^{\ast}$, SARTS and DYNORA have been proposed. The performance of such algorithms depend on the quality of their heuristic functions, because such algorithms estimate the search time based on the heuristic function. In real-world problem, however, we often fail to get an effective heuristic function beforehand. Therefore, we propose a new real-time algorithm that determines the sub-problem deadline based on the status of search space during sub-problem search process. That uses the cut-off method that is a dynamic stopping-criterion-strategy to search the sub-problem.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2004.04a
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• pp.164-167
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• 2004

In the paper is proposed a hierarchical adaptive fuzzy controller for balancing and position control of the inverted pendulum system. Because balancing control rules of the pendulum and position control rules of the cart can be opposite, it is difficult to design an adaptive fuzzy controller that satisfy both objectives. To stabilize the pendulum at a specified position, the hierarchical adaptive fuzzy controller consists of a robust indirect adaptive fuzzy controller for balancing, a forced disturbance generator which emulates heuristic control strategy, and a supervisory decision maker for the arbitration of two control objectives It is proved that all the signals in the overall system are bounded. Simulation results are given to verify the proposed adapt i ye fuzzy control method.

• Journal of The Korean Association For Science Education
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• v.19 no.4
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• pp.635-644
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• 1999

The effect of cooperative learning in a heuristic approach (four stage-problem solving strategy) that also emphasized molecular level representation was studied. Three high school classes (N=130) were randomly assigned to St group (using strategy individually), St-Co group (using strategy in cooperative group), and control group. After instruction, students' multiple-choice problem solving ability, strategy performing ability, and the perception of involvement were compared. Students' preferred instruction type was also examined. Although multiple-choice problem solving ability were not different significantly, a significant interaction between the treatment and the previous achievement level was found in strategy performing ability. Analysis of simple effects indicated that the medium-level students in the St group performed better than those in the St-Co group. In the perception questionnaire of involvement. however, the scores of the St group were significantly lower than those of the control group. The instruction type that students most preferred was also St-Co.

• Journal of the Korean Institute of Navigation
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• v.15 no.2
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• pp.39-47
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• 1991

As per the rapid development of world economics the marine traffic volume was increased accordingly and caused frequent disasters in human lives and natural environment in the consequence of accidents. As the result of the above they started to establish Vessel Traffic System(VTS) and separation scheme in waterway from 1960' to prevent the marin traffic accident but the problem of safety at sea appears now as neither fully defined nor sufficiently analysed. At the present, the dominant factor in establishing the strategy of marine traffic has been safety of navigation concerning only with the ship, but the risk of society derives almost wholly from the nature of cargo. To measure the degree of danger for each ship there is suggested concept of safety factor numbers denoting the level of latent danger in connection with ship and her cargo. In this paper, where the strategy of VTS is put on controlling density of safety factor for control area. it suggested algorithms how to assign the vessels and also to get optimal sequence of vessels located to a sector in the sense of minimizing the passage delay. For the formulation of problem, min max and 0-1 programming methods are applied and developed heuristic algorithm is presented with numerical example to improve the efficiency of calculation.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.50 no.11
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• pp.528-536
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• 2001

This paper proposes a method of solving a unit commitment problem using parallel tabu search(PTS) approach. Tabu search is a heuristic optimization method that has the tabu list to control the search process. To improve the searching ability of a global solution, we used a method of exchanging solutions among connected processors as a diversification strategy, and to reduce the computation time, a new evaluating method was proposed which evaluates only a changed par. To show the usefulness of the proposed method, we simulated for 10 units system and 110 units system. Numerical results show improvements in the generation costs and the computation time compared with other conventional methods.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.617-620
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• 1997

We have built a robot soccer system to participate in MIROSOT97. This paper represents hardware specification of our system and our strategy. We select a centralized on-line system for a soccer game. The paper explains hardware specifications of our system for later development. Also, the paper explains our strategy from two viewpoints. From the viewpoint of cooperation, some heuristic ideas are implemented. From the viewpoint of path plan, Cubic spline is used with cost function which minimized time, radius of curvature for smoothness, and obstacle potential field. Direct comparison will be realized in MIROSOT97.

• Journal of the Ergonomics Society of Korea
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• v.24 no.2
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• pp.57-63
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• 2005

Ergonomic intervention techniques were adopted to assess and control potential risk factors of work-related musculoskeletal disorders(WMSDs) in the automated light assembly manufacturing system. Ten different kinds of assembly workstations implemented with a conveyor system and twelve female workers were observed and evaluated with careful video film analysis. Several close examinations using sets of checklists established by qualified safety and health organizations, such as NIOSH, OSHA, and ANSI, were conducted and every workers and staffs in the site participated in the self-report questionnaires and off-line interviews. Typical risk factors and symptoms of the upper extremity musculoskeletal disorders were found and categorized into specific parts of body. To reduce risk factors of WMSDs and improve system productivity new revised workstation standards, physical dimensions, were suggested accordant with anthropometric characteristics of workers and a heuristic decision strategy of rotating shift work schedules according to work contents has proposed to mitigate cumulative physical stress. Finally, ergonomic programs of entire company to prevent WMSDs were structured.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.6 no.8
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• pp.63-71
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• 1983

Aggregate planning coordinate the control variable over long-term to apply a demand variable and forcasting. In order to necessary the goal that doesn't make an inter-contradiction and explicitly defined. We made a considerable point of system approach for scheduling establishment. It include the control variables of aggregate planning : 1) employment 2) over time working and idle time 3) inventory 4) delivery delay S) subcontract 61 long - term facility capacity. Each variables composed of pure strategy as like a decision of inventory level, a change of employment level, etc. md alternative costs make a computation on the economic foundation. But the optimum alternative costs represent the mixed pure strategy. The faults of this method doesn't optimum guarantee a special scheduling as well as increasing a number of alternative combination. Theoretical, Linear Decision Rule make an including all variables, but it is almost impossible for this model to develope actually And also make use of the aggregate planning problem for developing system approach : LDR, heuristic model, Search Decision Rule, all kind of computers, simulation. But these models are very complex, each variables get an extremely inter-dependence. So this study be remained by theory level, some approach methods has not been brought the optimum solution to apply in every cases.

• Journal of Distribution Science
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• v.12 no.10
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• pp.99-108
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• 2014

Purpose - The goals of this study are the following. First, this study focused on customer satisfaction of in-flight service. Specifically, in-flight duty free items were considered because of their potential value related with the differentiated strategy of airline companies. Second, this study analyzed feasible strategies that would fence off the aversive attitudes of consumers toward innovation regarding in-flight duty free items. Third, this study strived to discover implicit routes related with the reactions of of consumers to innovation. Fourth, the construal level theory was applied to the context of in-flight service. Psychological distance is expected to promote acceptance of innovation for duty free items. Research design, data, and methodology - This study consisted of three experiments. All data were collected through the participation of university students. First, the experiment employed a 2×2 between-subject design. The first independent variable was temporal distance (long vs. short of navigation time). The second independent variable was innovativeness (innovative duty free items vs. typical items). Further, experiment 2 involved a 2×2 between-subject design. The first independent variable was social distance (typical vs. atypical stewardess image). The second was innovativeness that was based on a pattern similar to that of the prior experiment. The third experiment involved a 2×2×2 design. The first and second independent variables were temporal distance and item innovation, respectively, based on the method of experiment 1. The third independent variable was cognitive depletion (depletion vs. control condition). Results - Experiment 1 demonstrated that the innovation of duty free items would need to consider the journey time of the airline. Specifically, innovative items were preferred in case of a long journey; typical items, however, were liked in a short journey. Further, experiment 2 demonstrated that, in spite of a short journey, innovative items would be preferred if an atypical stewardess was serving. An atypical stewardess was linked with social distance, and the psychological effects would activate a creative and flexible mindset that would fit with innovative duty free items. The final experiment was accomplished for the examination of cognitive processing of psychological distance on innovation-acceptance. Specifically, if the effects were related with systematic processing, then cognitive effort would be needed. In contrast, if they were related with heuristic processing, then such efforts would not be required. The same pattern appeared under both cognitive depletion and control condition; therefore, the effects of psychological distance were implied to be heuristic processing. Conclusions - Managers need to consider the navigation time, stewardess concepts, and depletion of consumers as important factors for innovative strategy regarding in-flight service. Longer journeys are more successful for innovative trials. Further, a more atypical stewardess image is more successful for atypical service. Long navigation and unfamiliar stewardesses may activate creative and flexible thinking. Further, cognitive depletion of consumers is not a dominant factor of psychological distance effects, because the effects are not related with systematic processing, but with heuristic processing.