• Journal of the Korean Society for Precision Engineering
• /
• v.10 no.3
• /
• pp.175-181
• /
• 1993

In this paper, a practical method to generate task strategies applicable to chamferless and high-precision assembly, is proposed. The difficulties in devising reliable assembly strategies result from various forms of uncertainty such as imperfect knowledge on the parts being assembled and functional limitations of the assembly devices. In approach to cope with these problems, the robot is provided with the capability of learning the corrective motion in response to the force signal trrough iterative task execution. The strategy is realized by adopting a learning algorithm and represented in a binary tree type database. To verify the effectiveness of the proposed algorithm, a series of simulations and experiments are carried out under assimilated real production environments. The results show that the sensory signal-to-robot action mapping can be acquired effectively and, consequently, the chamferless assembly can be performed successfully.

• International Commerce and Information Review
• /
• v.12 no.2
• /
• pp.161-182
• /
• 2010

This study tried to analyzed the relationship between market orientation, localization and performance in order to suggest to a methodology for performance 7hypothesis were constructed for analysis based on previous literature review. The results of empirical analysis shows that market orientation gave significant effect on firm's performance and localization. Localization also positively related to firm's performance. These result explains that firms which try to take superior of performance must build high level of market orientation should be realized and reacted the complicated market situation. such as consumer needs, competitor's action, change of technology and provider's action, etc. For this, management of uncertainty should be required through the high level of information-oriented.

• Journal of the Korea Safety Management & Science
• /
• v.6 no.2
• /
• pp.177-186
• /
• 2004

Decision analysis has becomes an important technique for decision making in the face of uncertainty. It is characterized by enumerating all the available courses of action, identifying the payoffs for all possible outcomes, and quantifying the subjective probabilities for the all possible random events. When the data are available, decision analysis becomes a powerful tool for determining an optimal course of action. We study the multi-attribute decision making in a compensatory models. In this paper, we use the entropy methods in weights calculating. For the purpose of making optimal decision, the data of five different car models are used. For computing, we used Visual Numerica Version 1.0 software package.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2009.05a
• /
• pp.337-338
• /
• 2009

Use of the recycled fine aggregate as a material of structural concrete is not easy currently because there are some problems, such as of quality control and the uncertainty of chemical and physical property. Thus, the results indicate that it is possible to produce high quality recycled fine aggregate for structure by microwave heating technology, friction and abrasion action.

• Proceedings of the KIEE Conference
• /
• 1999.07b
• /
• pp.791-793
• /
• 1999

In this paper, neural network-supervisory control method is proposed to minimize the effect of system uncertainty by load change and disturbance in the PID control system. In the proposed method, PID controller performs main control action by performing control within constraint error. And neural network-supervisory controller performs control action when error reaches the boundary of constraint error. Combining neural network-supervisory controller to guarantee the stability into PID control system, the resulting PID control system is expected to show better performance in the system with load change and disturbance. Simulation applying PID controller and neural network-supervisory controller showed excellence of proposed method.

• Proceedings of the KIEE Conference
• /
• 2005.10b
• /
• pp.89-91
• /
• 2005

In this paper, we propose a robust visual feedback controller with integral action for tracking control of n-link robot manipulators in the presence of constant bounded parametric uncertainties. The proposed control input has robustness to the parametric uncertainty and reduces tracking error in the steady-state. The stability of the closed-loop system is shown by Lyapunov method. The effectiveness of the proposed method is shown by simulation results on the 5-link robot manipulators with two degree of freedom.

• International Journal of Reliability and Applications
• /
• v.2 no.1
• /
• pp.37-48
• /
• 2001

This paper presents a new dynamic human reliability analysis method and its application for quantifying the human error probabilities in implementing management action. For comparisons of current HRA methods with the new method, the characteristics of THERP, HCR, and SLIM-MAUD, which are most frequency used method in PSAs, are discussed. The action associated with implementation of the cavity flooding during a station blackout sequence is considered for its application. This method is based on the concepts of the quantified correlation between the performance requirement and performance achievement. The MAAP 3.0B code and Latin Hypercube sampling technique are used to determine the uncertainty of the performance achievement parameter. Meanwhile, the value of the performance requirement parameter is obtained from interviews. Based on these stochastic obtained, human error probabilities are calculated with respect to the various means and variances of the things. It is shown that this method is very flexible in that it can be applied to any kind of the operator actions, including the actions associated with the implementation of accident management strategies.

• Korean Journal of Childcare and Education
• /
• v.9 no.5
• /
• pp.5-35
• /
• 2013

This study aimed to figure out the action research process and experience and to examine the significance of such experiences to teachers who implemented action research. This study took in-depth interviews with three experienced teachers and analyzed collected data. In order to carry out action research, they must start from the point of their standing and find the most suitable methodology for the method of their own life. There might cases that they felt strangeness because of unexpected reaction, and struggled hard against uncertainty. But, they finally experienced the joy of completion of their research. Such experiences gave them opportunities to reflect on their own lives and to escape any mannerism through concentration and enthusiasm. And they could recognize the importance of record of ordinary life in a meaningful way, and also recognize the meaning of process as a new start other than failure. So, they made efforts to grant meaning in a widened perspective. And they found themselves to live as empirical researchers. This study demonstrates that teachers in the educational field could not only have sufficient quality to be researchers but also need to be more aware of such talents.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.18 no.6
• /
• pp.85-95
• /
• 2015

Recent years, nationwide projects for ecological restoration are implemented with emerging issues on the stream ecosystem. In order to enhance effectiveness of the ecosystem restoration and reduce negative impact, the appraisal of effectiveness through the follow-up monitoring and the adaptive management process are executed in consecutive phase. In this study, planning phase, monitoring and adaptive management in Hakui stream which is part of An Yang stream restoration project is introduced as representative ongoing case of effective adaptive management. The aim of this study is to verify the adaptive management process and suggest direction of effective restoration. Restoration project of Hakui stream resulted in increasing number and diversity of species (vegetation, fish, bird, invertbrates, amphibian and reptilia) according to monitoring from 2004 to 2013, and enhancing natural river landscape by evaluation of river naturalness among 2001(before restoration), 2007 (after), 2015 (recent). However, excessive vegetation expansion or sediment deposition on channel over time caused unexpected results such as terrestrialization or degradation of habitats. Adaptive management action such as removing disturbance species (Humulus japonicus)(2007), coppicing willow (2007), release of march snail (2007), creation of wetland (2014) were implemented based on monitoring results. And then appraisal of management action was discussed.

• Journal of the Korean earth science society
• /
• v.28 no.5
• /
• pp.635-642
• /
• 2007

Using data from 132 telephone interviewees, we examined the role of affective-cognitive ambivalence in forming overall attitude and behavior toward toxic chemical and radioactive waste issues in Marion, Ohio in the U.S. In order to compare attitudinal preference, participants were divided into four A-C groups: action-group (Affective+/Cognitive+), detached-group (A-/C+), concerned-group (A+/C-), and inaction-group (A-/C-). Affective and cognitive components interacted, producing redundant influences on overall attitudes and judgments as frequently observed and postulated in previous attitude studies. The results showed that the action-group who were feeling unsafe and believed that environmental accidents had happened or are happening in Marion were less willing to move to the area than other three groups who were feeling safe and/or doubted reports of contamination and its relation with leukemia. Affective and cognitive components were found to have redundant influences on overall attitude. It was also observed that affective-cognitive ambivalence theory has a great potential for explaining the mechanism by which people form attitudes, especially when people have moderate or positive feelings (e.g. sympathy or eagerness for resources) toward the objects and/or when uncertainty is a major feature of environmental issue under consideration (e.g. global climate change).