• Journal of Institute of Control, Robotics and Systems
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• v.5 no.5
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• pp.614-621
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• 1999

In this paper, the analytical appproaches are presented for jointly determining the profit-miximizing configuration of the fault-tolerance real time modular cell manufacturing system. The transient(time-dependent) analysis of Markovian models is firstly applied to modular cell manufacturing system from a performability viewpoint whose modeling advantage lies in its ability to express the performance that truly matters - the user's perception of it - as well as various performance measures compositely in the context of application. The modular cells are modeled with hybrid decomposition method and then availability measures such as instantaneous availability, interval availability, expected cumulative operational time are evaluated as special cases of performability. In addition to this evaluation, sensitivity analysis of the entire manufacturing system as well as each machining cell is performed, from which the time of a major repair policy and the optimal configuration among the alternative configurations of the system can be determined. Secondly, the recovery policies from the machine failures by computing the minimal number of redundant machines and also from the task failures by computing the minimum number of tasks equipped with detection schemes of task failure and reworked upon failure detection, to meet the timing requirements are optimized. Some numerical examples are presented to demonstrate the effectiveness of the work.

• BMB Reports
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• v.40 no.3
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• pp.396-403
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• 2007

Proline accumulation has been shown to correlate with tolerance to drought and salt stresses in plants. We attempt to introduce the wild-type, mutant, and fusion proBA genes derived from Bacillus subtilis into Arabidopsis thaliana under the control of a strong promoter cauliflower mosaic virus 35S (CaMV35S). The transgenic plants produced higher level of free proline than control and the overproduction of proline resulted in the increased tolerance to osmotic stress in transgenic plants. Besides, the mutation in proBA genes, which were proved to lead $\alpha$-glutamyl kinase ($\alpha$-GK) reduces sensitivity to the end-product inhibition and the fusion of proB and proA also result in increasing proline production and confer osmotolerance in transgenic lines.

• Journal of Information Technology Services
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• v.6 no.3
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• pp.163-177
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• 2007

This research is the concept of a game addiction absorbed in the game based on the review and analysis of factors that affect the characteristics of game addiction, it is appropriate to extract the purpose of factors. Game addiction factor is composed of a total of 32 questions, and a total of 356 people, to collect data through surveys. Factor analysis of the collected data to the target as a result of physical and mental problems, loss of control, tolerance, and avoidance of real world consists of three sub-factors. Factors that affect flow of tolerance and loss of control, and avoid the real world, including two sub-factors that could determine. Diagnostic game addiction factor in the reliability coefficients (Cronbach alpha) is a robust .966 aspects in the event. The game addiction scale score of 90-game addiction by category 'regular user', 90 points and 114 between the terms 'potentially dangerous user' and 13 percent of the overall. Finally, more than 115 points in the 'high-risk user' has been classified as 5% of the overall distribution of the notice that. Such factors extract game is a game addict, addicted users of the game and tend to properly evaluate and navigate game addiction-related problems early in the game addiction and found it could be used properly.

• Smart Structures and Systems
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• v.30 no.1
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• pp.35-47
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• 2022

Data-driven engineering is crucial for information delivery between design, fabrication, assembly, and maintenance of prefabricated structures. Design for manufacturing and assembly (DfMA) is a critical methodology for prefabricated bridge structures. In this study, a novel concept of digital engineering model that combined existing knowledge of DfMA with object-oriented parametric modeling technologies was developed. Three-dimensional (3D) geometry models and their data models for each phase of a construction project were defined for information delivery. Digital design models were used for conceptual design, including aesthetic consideration and possible variation during fabrication and assembly. The seismic performance of a bridge pier was evaluated by linking the design parameters to the calculated moment-curvature curves. Control parameters were selected to consider the tolerance control and revision of the digital models. Digitalized fabrication of the prefabricated members was realized using the digital fabrication model with G-code for a concrete printer or a robot. The fabrication error was evaluated and the design digital models were updated. The revised fabrication models were used in the preassembly simulation to guarantee constructability. For the maintenance of the bridge, the as-built information was defined for the prefabricated bridge piers. The results of this process revealed that data-driven information delivery is crucial for lifecycle management of prefabricated bridge piers.

• Journal of Pharmacopuncture
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• v.25 no.3
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• pp.268-275
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• 2022

Objectives: This toxicological study was performed to assess for potential toxicity and to determine the approximate lethal dose of SU-Eohyeol pharmacopuncture (SUEP) following a single intramuscular injection of SUEP into male and female Sprague-Dawley (SD) rats. Methods: The groups in our experiment consisted of an experimental group treated with SUEP at a dose of 1.0 mL/animal and a control group injected with a normal saline solution, and five male and female rats were placed in each group. Each animal was administered a single intramuscular injection. We monitored all rats for clinical signs and body weight changes for 14 days after administration. At the end of the observation period, the rats were euthanized and autopsied, and localized tolerance examinations were conducted at the site of administration of the test substance. Results: There were no deaths in either sex in the SUEP-treated group. There was no significant difference between the SUEP-treated group and the control group in the clinical signs and weight changes among the rats. In addition, no significant SUEP-related changes were observed on autopsy findings or local tolerance examinations at the injection site by histopathological examination. Conclusion: Our results suggest that the approximate lethal dose of a single intramuscular administration of SUEP in female and male rats under the conditions of this study is greater than 1.0 mL/animal. To determine the safety of the use of SUEP in Korean medical clinical practice, additional toxicity studies will be needed.

• Proceedings of the IEEK Conference
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• 2000.06e
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• pp.151-154
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• 2000

Used analog control systems have been converted into digital control systems due to performance degradation and difficulty of maintenance. There are few domestic DCS (Distribued Control System)s that have been applied to Bower plant. To apply a demestic DCS to power plant, the reliability, redundacny, and fault tolerance of DCS is important. Besides those items, the control action of control function block is also important. In this paper, we describe the requirements that PID control function block has to have, and implement a PID control function block that satisfies those requirements. Finally. simulation result using digital simulator for boiler system in thermal power plant shows the validity of a implemented PID control function block.

• Proceedings of the KIPE Conference
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• 1998.10a
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• pp.176-181
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• 1998

The parallel inverter is popularly used because of its fault-tolerance capability, high-current outputs at constant voltages and system modularity. The conventional parallel inverter usually employs active and reactive power control of frequency and voltage droop control. However, these approaches have the disadvantages that the response time of parallel inverter control is slow against load and system parameter variation to calculate active, reactive power, frequency and voltage. This paper describes a novel control scheme for power equalization in parallel-connected inverter. The proposed scheme has a fast power balance control response, a simplicity of implementation, and inherent peak current limiting capability since it employees an instantaneous current/voltage control with output voltage and current balance and output voltage regulation. A design procedure for the proposed parallel inverter controller is presented. Furthermore, the proposed control scheme is verified through the experiment in various cases such as the system parameter variation, the control parameter variation and the nonlinear load condition.

• Journal of Auto-vehicle Safety Association
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• v.15 no.2
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• pp.13-20
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• 2023

This paper presents a fault tolerant control strategy for Steer-by-Wire (SbW) systems. Among many problems to be solved before commercialization of SbW systems, maintaining reliability and fault tolerance in such systems are the most pressing issues. In most previous studies, dual steering motors are used to achieve actuation redundancy. However, relatively few studies have been conducted to introduce fault tolerant control strategies using rear wheel steering system. In this work, an actuator fault in front wheel steering is compensated by active rear wheel steering. The proposed fault tolerant control algorithm consists of disturbance observer and sliding mode control. The fault tolerant control performance of the proposed approach is validated via computer simulation studies with Carsim vehicle dynamics software and MATLAB/Simulink.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1348-1351
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• 1997

The federated Kaman filter(FKF) is being widely used in many multisensor navigatiion systems. It is know that the FKF has advantages of simplicity and fault-tolerance over other decentralized filter techniques. In this paper, optimal and suboptimal FKF configuratiions are mentioned and a covariance analysis technique for the suboptimal FKF is newly presented. The suboptimal FKF configuration, known as No-reset(NR) mode, has better fault tolerance capability than the optimal FKF coniguratioin. In the suggested technique, a suboptimal fusion process of FKF is considered a swell as suboptimal gains of local filters. An upper boun of error covariance for suboptimal FKF is derived. Also, it is mathematically shown that this bound is smaller thanexisting bound in the literatrue. A vehicle-navigaion system is designed using the FKF. In thissystem, a map constraing equation is introduced and used as a measurement equatioin of Kalman filter. Performance analysis is done by the suggested covariance analysis techniques.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.13 no.3
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• pp.84-90
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• 2004

Today, automobile world market is highly competitive. In order to strengthen the competitiveness, quality of automobile is recognized as important and efforts are being made to improve the quality of manufactured components. The directional ability of automobile has influence on driver directly and hence it must be solved on the preferential basis. In the present research, an automated vision system has been developed to inspect the front chassis module. To interpret the inspection data obtained for front chassis module, new interpreting algorithm have been developed. Previously the control of tolerance of front chassis module was done manually. With the help of the new algorithm developed, the dimension is calculated automatically to check whether the front chassis module is within the tolerance limit or not.