• Journal of Institute of Control, Robotics and Systems
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• v.2 no.2
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• pp.88-95
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• 1996

It is inevitable for local systems to have deviations which represent interactions and modeling errors originated from the decomposition process of a large scale system. This paper presents a decentralized control scheme for interconnected systems using local linear models and a neuro-coordinator. In the proposed method, the local system is composed of a linear model and unknown deviations caused by linearizing the subsystems around operating points or by estimating parameters of the subsystems. Because the local system has unmeasurable deviations we define a local reference model which consists of a local linear model and a neural network to estimate the deviations indirectly. The reference model is reformed into a linear model which has no deviations through a transformation of input variables and we obtain an optimum feedback control law which minimizes a local performance index. Finally, we derive a decentralized feedback control law which consists of local linear states and neural network outputs. In the decentralized control, the neuro-coordinator generates a corrective control signal to cancel the effect of deviations through backpropagation learning with the errors obtained from the differences of the local system outputs and reference model outputs. Also, the stability of local system is proved by the degree of learning of the neural network under an assumption on a neural network learning index. It is shown by computer simulations that the proposed control scheme can be applied successfully to the control of a biased two-link planar robot manipulator.

• Journal of Korean Society for Quality Management
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• v.40 no.3
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• pp.337-346
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• 2012

Purpose: A Control chart is one of the important statistical process control tools that can improve processes by reducing variability and defects. Methods: In the present study, we propose the local $T^2$ multivariate control chart that can efficiently detect abnormal observations by considering the local pattern of the in-control observations. Results: A simulation study has been conducted to examine the property of the proposed control chart and compare it with existing multivariate control charts. Conclusion: The results demonstrate the usefulness and effectiveness of the proposed control chart.

• Radiation Oncology Journal
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• v.34 no.2
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• pp.113-120
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• 2016

Purpose: The association between metabolism and cancer has been recently emphasized. This study aimed to find the prognostic significance of obesity in advanced stage rectal cancer patients treated with surgery and radiotherapy (RT). Materials and Methods: We retrospectively reviewed the medical records of 111 patients who were treated with combined surgery and RT for clinical stage 2-3 (T3 or N+) rectal cancer between 2008 and 2014. The prognostic significance of obesity (body mass index [BMI] ${\geq}25kg/m^2$) in local control was evaluated. Results: The median follow-up was 31.2 months (range, 4.1 to 85.7 months). Twenty-five patients (22.5%) were classified as obese. Treatment failure occurred in 33 patients (29.7%), including local failures in 13 patients (11.7%), regional lymph node failures in 5, and distant metastases in 24. The 3-year local control, recurrence-free survival, and overall survival rates were 88.7%, 73.6%, and 87.7%, respectively. Obesity (n = 25) significantly reduced the local control rate (p = 0.045; 3-year local control, 76.2%), especially in women (n = 37, p = 0.021). Segregation of local control was best achieved by BMI of $25.6kg/m^2$ as a cutoff value. Conclusion: Obese rectal cancer patients showed poor local control after combined surgery and RT. More effective local treatment strategies for obese patients are warranted.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.53 no.2
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• pp.82-89
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• 2004

In this paper, an active magnetic bearing(AMB) system is designed and controlled using a digital Proportional-Integral-Derivative(PID) control concept. The plant dynamics consisting of actuator and rigid rotor dynamics are described. A digital PID controller with a global control and a local control concept is designed and implemented using digital signal processor. Some experiments are conducted with each global control and local control concept. These include start-up test, impulse test, whirl response, and generator load test. The experimental results and comparison between those of a global control and a local control indicate that the global control of concept has impressive static and dynamic control performance for the prototype considered. From the whirl test, the developed system set can be controlled within about $\pm10\mu\textrm{m}$ gap variation at the rotational speed of 6000rpm and generate the AC power of frequency of $60\textrm{Hz}$, voltage of 100V and current of 0.8$\textit{A}$.

• The Journal of the Korean dental association
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• v.56 no.1
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• pp.49-57
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• 2018

The most widely used method of pain control in dental practice is to block the pathway of painful impulses by local anesthesia. For a maximum effect of pain control at outpatient minor operation, regional anesthesia including nerve block must be performed. This issue includes various dental local anesthetic techniques on mandible, maxilla and considerations for selection of dental local anesthetics according to patient's age, duration of operation. Additionally, current conscious sedation technique combined with local anesthesia will be introduced for control of patient's anxiousness. Based on patient's general condition, severity of operation, local anesthesia sometimes must be changed into general anesthesia to avoid failure of dental practice. The exact choice of anesthetic techniques for minor operations at dental outpatient clinic must not be underestimated for complete success of pain control.

• Journal of applied mathematics & informatics
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• v.6 no.3
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• pp.697-726
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• 1999

In this paper we develop a now procedure to control stepsize for linear multistep methods applied to semi-explicit index 1 differential-algebraic equations. in contrast to the standard approach the error control mechanism presented here is based on monitoring and contolling both the local and global errors of multistep formulas. As a result such methods with the local-global stepsize control solve differential-algebraic equation with any prescribed accuracy (up to round-off errors). For implicit multistep methods we give the minimum number of both full and modified Newton iterations allowing the iterative approxima-tions to be correctly used in the procedure of the local-global stepsize control. We also discuss validity of simple iterations for high accuracy solving differential-algebraic equations. Numerical tests support the the-oretical results of the paper.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.05a
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• pp.841-844
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• 2008

This paper describes technical method about remote control and monitoring of local system by use internet web connection system, which connect local system and system manager works in long distance office. The local system, which will be controlled remotely have constructed with analog/digital signal acquisition device, signal control board and their software. The local systems are constructed with several electronic modules need AC or DC power supply to operate the right way. We used NI labview software to control and monitoring of local system. The computer server for remote connection are constructed with Apache web server, PHP and MySQL ODBC. The experiment for the remote control are need internet web browser which load local control software. By use of web system, we have experimented control and monitoring of local electronic module.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.4
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• pp.543-550
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• 2008

This paper proposes an voltage and reactive power control methodology, which is motivated towards implementation in the korea power system. The main voltage control devices are capacitor banks, reactor banks and LTC transformers. Effects of control devices are evaluated by local subsystem's cost computations. This local subsystem is decided by 'Tier' and 'Electrical distance' in the whole system. The control objective at present is to keep the voltage profile within constraints with minimum switching cost. A robust control strategy is proposed to make the control feasible and optimal for a set of power-flow cases that may occur important event from system. This studies conducted for IEEE 39-bus low and high voltage contingency cases indicate that the proposed control methodology is much more effective than PSS/E simulation tool in deciding switching of capacitor and reactor banks.

• Korean Journal of Health Education and Promotion
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• v.22 no.2
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• pp.77-95
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• 2005

Objectives: This study measured the extent of local legislators' support for tobacco control policies and identified the predictors of that. Methods: Local legislators, from 21 Gu in Seoul Metropolitan City, underwent a self-administrated questionaire during the 6-week period from December 1, 2004 to January 15, 2005. Multiple linear regression model was used to assess relationships between five groups of variables(political factors including political ideology, personal characteristics, tobacco experiences, tobacco knowledge, contact with local health officers) and support for tobacco control policies based on an 11-item scale. Results: The rates of support for 'penalizing merchants who sell cigarettes to minors' and 'instituting a law mandating that parents should not smoke in a car when children are present' were highest as 87.5% and 82.0% respectively, and those for 'increasing price of cigarettes' and 'regulating stores that sell cigarettes' were lowest as 52.2% and 51.7% respectively. Support was higher among local legislators who thought government had a duty to promote healthy life styles, knew second-hand smoke could cause lung cancer, knew tobacco caused more deaths than alcohol. Support among ex-smokers and nonsmokers was higher than current smokers. Conclusions: The findings indicate that local legislators who oppose tobacco control measures may not be opposed to tobacco control per se, but are more generally opposed to a government role in health promotion, Thus, Tobacco control advocates need to be more attentive to the way tobacco control issues are framed for particular legislators. Further, they could work to increase tobacco knowledge among local legislators.

• Journal of Agricultural Extension & Community Development
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• v.26 no.4
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• pp.221-232
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• 2019

The purpose of this paper is empirically to identify the factors influencing local food purchase intention. And this study compares to the difference between local food consumer and hypermarket consumer's attitudes toward local food, food lifestyle, and subjective norm. Data were collected from 319 local food consumer and 179 hypermarket consumer to measure the following; attitude toward local food; subjective norm; perceived behavioral control; food lifestyles; demographic information. Results showed that local food consumers are significant differences on attitudes towards health, environment, and local economy. Results also found that subjective norm and perceived behavioral control are significant differences between local food consumer and hypermarket consumers. It means that consumers who express a strong intention to purchase local food seems to link to the food lifestyles. The study suggests that producers and retailers need to develp campaigns explaining how consuming local food supports local businesses and farmers, which will reinforce personal values associated with local consumption.