• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.153-158
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• 2000

This paper addresses an intelligent robot control system using an off-line programming to teach a precise assembly task of electronic components in a flexible way. The investigated task consists of three job: heat caulking test, soldering on a circuit board, and checking of soldering defects on the back cover of a camera. This study investigates the remodelling of the most complicated cell in terms of the accuracy and fault rate among the twelve cells in a camera back-cover assembly line. We have attempted to enhance back-cover assembly line. We have attempted to enhance soldering quality, to add task flexibility, to reduce failure rate, and to increase product reliability. This study modifies the cell structure, and improves the soldering condition. The developed all system implements the real-time control of assembly with vision data, and realized an easier task teaching on off-line programming.

• Clinical and Experimental Reproductive Medicine
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• v.44 no.1
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• pp.1-7
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• 2017

The task force of the Korean Society for Reproductive Immunology recommends intravenous immunoglobulin G treatment in women with reproductive failure, including recurrent pregnancy loss and/or repeated implantation failure, who show cellular immune factors such as abnormal natural killer cell levels, natural killer cell cytotoxicity, and/or type 1 T helper immunity.

• Safety and Health at Work
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• v.5 no.1
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• pp.1-6
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• 2014

Background: Workflow interruptions during surgery may cause a threat to patient's safety. Workflow interruptions were tested to predict failure in action regulation that in turn predicts near-accidents in surgery and related health care. Methods: One-hundred-and-thirty-three theater nurses and physicians from eight Swiss hospitals participated in a cross-sectional questionnaire survey. The study participation rate was 43%. Results: Structural equation modeling confirmed an indirect path from workflow interruptions through cognitive failure in action regulation on near-accidents (p < 0.05). The indirect path was stronger for workflow interruptions by malfunctions and task organizational blockages compared with workflow interruptions that were caused by persons. The indirect path remained meaningful when individual differences in conscientiousness and compliance with safety regulations were controlled. Conclusion: Task interruptions caused by malfunction and organizational constraints are likely to trigger errors in surgery. Work redesign is recommended to reduce workflow interruptions by malfunction and regulatory constraints.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.156-161
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• 2020

In an environment that operates multiple UAVs, the use of a decentralized task allocation algorithm has more robustness from a single failure of UAV on the mission because there is no central command center. In addition, UAVs have situational awareness and redistribute tasks among themselves, which can expand the mission range. The use of multiple UAVs in a mission has increased as the agent hardware has decreased in size and cost. The decentralized mission-planning algorithm has the advantages of a larger mission range and robustness to a single failure during the mission. This paper extended the type of mission the uses CBBA, which is the most well-known decentralized task allocation algorithm, to the point mission and en-route mission. This will describe the real mission situation that has the purpose of surveillance. A Monte-Carlo simulation was conducted in the case of multiple agents in the task-rich environment, and the global rewards of each case were compared.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.10
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• pp.755-767
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• 2003

This paper proposes a robust fault-tolerant control framework for robot manipulators to maintain the required performance and achieve task completion in the presence of both partial joint failures and complete joint failures and uncertainties. In the case of a complete joint failure or free-swinging joint failure causing the complete loss of torque on a joint, a fully-actuated robot manipulator can be viewed as an underactuated robot manipulator. To detect and identify a complete actuator failure, an on-line fault detection operation is also presented. The proposed fault-tolerant control system contains a robust adaptive controller overcoming partial joint failures based on robust adaptive control methodology, an on-line fault detector detecting and identifying complete joint failures, and a robust adaptive controller overcoming partial and complete joint failures, and so eventually it can face and overcome joint failures and uncertainties. Numerical simulations are conducted to validate the proposed robust fault-tolerant control scheme.

• Korean Journal of Childcare and Education
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• v.12 no.3
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• pp.21-39
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• 2016

The purpose of this study was to examine the relationship between parental attribution and self-perception in parenting roles according to parenting success or failure situations. A total of 138 mothers who have toddlers in Seoul and other big cities in Korea completed questionnaires, and data were analyzed by paired t-test, Pearson's correlation coefficient, Fisher's Z score, and multi-regression. The results are as follows: First, mothers in parenting success situations showed higher parental attribution than mothers in parenting failure situations. Second, correlations between parental attribution and self-perception in parenting roles turned out to be significantly different between parenting success situations and failure situations. Third, both internal attribution such as ability and effort, and external attribution such as child behavior and task difficulty, significantly predicted self-perception in parenting roles including equilibrium feeling, competence, satisfaction and parenting investment, especially in parenting failure situations. The implications of the difference in parental attribution between parenting success and failure situations have been discussed.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.8
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• pp.31-37
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• 2019

The inter-development of FMECA is very important to assess the effect of potential failures during system operation on mission, safety and performance. Among these, criticality analysis is a core task that identifies items with high risk and selects the analyzed objects as the key management targets and reflects their effects to the design optimization. In this paper, we analyze the theory related to criticality analysis following US military standard, and propose a method to quantify the failure effect probability for objective criticality analysis. The criticality analysis according to the US military standard depends on the subjective judgment of the failure probability. The methodology for quantifying the failure effect probability is presented by using the reliability theory and the Bayes theorem. The failure rate is calculated by applying the method to quantify failure effect probability.

• Journal of Industrial Technology
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• v.20 no.B
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• pp.201-206
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• 2000

A priori information of object is needed to control in some well known control methods. But we can't always know a priori information of object in real world. In this paper, the inverted pendulum is simulated as a control task with the goal of learning to balance the pendulum with no a priori information using neural network controller. In contrast to other applications of neural networks to the inverted pendulum task, the performance feedback is unavailable on each training step, appearing only as a failure signal when the pendulum falls or reaches the bound of track. To solve this task, the delayed performance evaluation and the learning of nonlinear of nonlinear functions must be dealt. Reinforcement learning method is used for those issues.

• Knowledge Management Research
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• v.13 no.4
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• pp.101-116
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• 2012

Knowledge management system is crucial for increasing organizational performance. However, despite this importance of knowledge management system, many companies fail to facilitate individual employees' knowledge sharing. One of reasons for this failure is the lack of consideration of how individual employees' characteristics and their interpersonal relationship influence on individual-level knowledge sharing. To explain individual-level knowledge sharing, this study investigates the mechanism that employees engage in knowledge sharing activities with their coworkers from the social exchange perspective. We have two purposes of study. First, we examine whether coworker's task-related help seeking affects employee's knowledge sharing with them. Second, we investigate the influence of help-seeker' characteristics as moderators on the relationship between task-related help seeking and knowledge sharing. Specifically, we considered coworker's maladjustment, LMX, and ability as moderators. Our analysis of 192 employees shows that the main effect of coworker's task-related help seeking on knowledge sharing is not significant. However, coworker's maladjustment and LMX moderate the relationship between task-related help seeking and knowledge sharing. The positive relationship between task-related help seeking and knowledge sharing is stronger when help seeker's maladjustment is high than when it is low. And the positive relationship between task-related help seeking and knowledge sharing is weaker when help seeker's LMX is high than when LMX is low. The results of this study have theoretical implications that enrich our understanding of individual-level knowledge sharing, and managerial implications that suggest employees' appropriate attitudes to facilitate knowledge sharing in a coworker relationship.

• Communications of the Korean Institute of Information Scientists and Engineers
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• v.30 no.2
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• pp.49-58
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• 2012