• International Journal of Fuzzy Logic and Intelligent Systems
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• v.3 no.2
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• pp.244-250
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• 2003

In this paper, the relationship between a slave robot and the uncertain remote environment is modeled as the impedance to generate the virtual force to feed back to the operator. For the control of a tele-operated mobile robot equipped with camera, the tele-operated mobile robot take pictures of remote environment and sends the visual information back to the operator over the Internet. Because of the limitation of communication bandwidth and narrow view-angles of camera, it is not possible to watch the environment clearly, especially shadow and curved areas. To overcome this problem, the virtual force is generated according to both the distance between the obstacle and robot and the approaching velocity of the obstacle. This virtual force is transferred back to the master over the Internet and the master(two degrees of freedom joystick), which can generate force, enables a human operator to estimate the position of obstacle in the remote environment. By holding this master, in spite of limited visual information, the operator can feel the spatial sense against the remote environment. This force reflection improves the performance of a tele-operated mobile robot significantly.

• Proceedings of the KIEE Conference
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• 1991.07a
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• pp.795-798
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• 1991

The hybrid positon/force control is required when two or more robots perform a coorperative task in a uncertain environment, or when single robot does a task with a constant force to the environment. In this paper, a new control algorithm which control simultaneously the position and the force are proposed, however, especially the conventional position controller employed in the present robot control is used. Moreover, in order to improve the output response characteristics of the system, the PI gains which were computed from the PI gain tunning techniques, are varied based on the results of the Fuzzy algorithm.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.12 no.1
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• pp.111-122
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• 2001

This study analyzed the relationships among perceptions of uncertainty, environmental characteristics and strategy maker\`s actual decision such as resource allocation in different organizational subunits by focusing on the hotel general managers in two different countries Korea and Japan. The results show that managerial perceptions of the environment would vary across organizations within an industry but it was surprising to fad that managerial perceptions did not vary more substantially across countries. General managers in both countries perceived government regulator\`s actions to be the most uncertain environmental factor. Hotels in Japan were more geared toward external effectiveness than were hotels in Korea. The findings of this study also suggest that when the organization faces high environmental uncertainty, it places greater emphasis on extemally oriented functions such as market research and product development.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.1
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• pp.192-199
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• 2008

In order for a mobile robot to move under unknown or uncertain environment. it is very important to collect environmental information. This paper suggests a traveling algorithm which leads to the map building algorithm and the $A^*$ algorithm under the assumption that environmental information should already be collected. In order to apply the proposed traveling algorithm to a real mobile robot. this paper additionally discusses a path amendment algorithm. For the purpose of verifying the proposed algorithms, several simulations are executed based on a UI host program-based simulation interface and an experiment is executed using a mobile robot under a real unknown environment.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.7-12
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• 1992

This paper proposes a sensor-based path planning method which utilizes fuzzy logic and neural network for obstacle avoidance of a mobile robot in uncertain environments. In order to acquire the information about the environment around the mobile robot, the ultrasonic sensors mounted on the front of mobile robot are used. The neural network, whose inputs are preprocessed by ultrasonic sensor readings, informs the mobile robot of the situation of environment in which mobile robot is at the present instant. Then, according to the situation class, the fuzzy rules are fired to make a decision on the mobile robot action. In addition, this method can be implemented real time since the number of fuzzy rules used to avoid the obstacle is small. Fuzzy rules are constructed based on the human reasoning and tuned by iterative simulations. The effective of the proposed avoidance method is verified by a series of simulations.

• Journal of Korean Society for Quality Management
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• v.23 no.3
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• pp.156-166
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• 1995

Job shop scheduling problem is a complex system and an NP-hard problem. Thus it is natural to look for heuristic method. We consider the multi-part production scheduling problem for quality level in a job shop scheduling under the existence of alternative routings. The problem is more complex if the processing time is imprecision. It requires suitable method to deal with imprecision. Fuzzy set theory can be useful in modeling and solving scheduling problems with uncertain processing times. Li-Lee fuzzy number comparison method will be used to compare processing times that evaluated under fuzziness. This study presents heuristic method for quality level in bottleneck-based job shop scheduling under fuzzy environment. On the basis of the proposed method, an example is presented.

• Journal of Advanced Marine Engineering and Technology
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• v.30 no.8
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• pp.919-926
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• 2006

To move in unknown or uncertain environment, a mobile robot must collect informations from various sensors and use it to construct a representation of the external world. Ultrasonic sensor can provide range data for this purpose in a simple cost-effective way. However conventional ultrasonic sensor system for a mobile robot are not sufficient for environment recognition because of their large beam opening angle, specular reflection. This paper describe on environmental perception algorithm which can solve these problems in case using ultrasonic sensor. The algorithm consist of two parts. One is to solve beam opening angle problem by fusion from multiple ultrasonic sensors. The other is to cope with specular reflection problem in wall line extract, which is based on Hough Transform. Experiments to verify the validity of the proposed algorithm are carried out, and the results are provided at last part in this paper.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.63
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• pp.245-260
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• 2014

This study is aimed to summarize a tense situation of Risk management for Kaesong Industrial Business Enterprise in 2013 and to investigate trade insurance of K-sure. Now we have to find a new way to protect Kaesong Industrial Business Enterprises from uncertain environment and also need to prevent a recurrence of parallel cases in the domain of South-North economic cooperation in Korean peninsula. There are two method to protect Kaesong Industrial Business Enterprises. First they rely on the Korea government for protection. Second they need to effect trade insurance of K-sure. such as Export Credit Guaranty or Short-term Export Insurance. They shall create a wise predictable environment to protect Kaesong Industrial Business Enterprises themselves without resort to Korea government. Of course there are many things left behind to consider I hope it will be helpful to those who prepare South-North economic cooperation especially in Kaesong Industrial Complex.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2846-2848
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• 2000

In this paper we propose a path planning method for an autonomous mobile robot based on genetic algorithms(GAs). There have been a number of methods proposed for the path planning of a mobile robot. However, few algorithms have been developed for an on-line path planning of a mobile robot with the uncertain information of a task environment. Therefore, we propose a path planning algorithms based on GAs that has ability of creating path planning without the perfect information of a task environment and an ability of planning the efficient path by on-line process. Then we show a possibility of the practical use with the results of simulations and experiments.

• Proceedings of the KIEE Conference
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• 1999.07g
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• pp.2998-3000
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• 1999

Robot soccer is a challenging research area in which multiple robots collaborate in adversarial environment to achieve specific objectives. We designed and built the robotic agents for robot soccer, especially MIROSOT. We have been developing the appropriate vision algorithm, algorithm for ball tracking and prediction, algorithms for collaboration between the robots in an uncertain dynamic environment. In this work we focus on the development of ball tracking and prediction algorithm using Kalman filter. Robustness and feasibility of the proposed algorithm is demonstrated by simulation.